Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent di...Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent diggers that can move in unstructured environments and navigate past barriers.Furthermore,root growth has a high energy efficiency since it penetrates the soil at its tip,adding new material without displacing the already grown portion,minimizing the energy dissipation due to friction and lowering the inertia.A robot inspired by the growth of roots could be used in search and rescue or environmental monitoring.The design of a soft robot inspired by root growth is presented in this article.The robot body consists of a cylindrical plastic membrane folded inside itself.The robot body is inflated,and its tip is everted,expanding its length as air is blown from the base.Velcro straps are placed on the membrane’s exterior surface to keep it folded.The head is positioned inside the tip,which houses the mechanism that controls the growth direction.It consists of housing for two balloons that are selectively inflated,and their expansion applies pressure on the exterior surface,opening the Velcro straps and determining the growth direction.The robot was constructed,and a kinematic model of its motion in the plane was created and compared with experimental data.The error in predicting the turning angle is only 5%,and the resulting predicted position differs on average by 55 mm on a total length of 850 mm.展开更多
Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,...Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.Methods:Twenty-two barrows(initial body weight:32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum,and allotted to 1 of 11 experimental diets in a 4-period Youden Square design.A fat-free diet was formulated using cornstarch,soy protein isolate and sucrose.Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch.All diets contained 26% sugar beet pulp and 0.40% chromic oxide.Results:The endogenous loss of ether extract(EE) was lower than that of acid-hydrolyzed fat(AEE;P < 0.01).There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources(P < 0.05).The SID of AEE for palm oil was lower than that of sunflower oil,corn oil,canola oil,rice oil and flaxseed oil(P < 0.01).The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%.Although the AID of EE was greater than that of AEE(P < 0.01),there was no significant difference in SID of EE and AEE except for palm oil.The ratio of unsaturated to saturated fatty acids(U/S) had a positive correlation with SID of fat(P < 0.05),whereas C16:0 and long chain saturated fatty acids(LSFA) were significant negatively correlated with SID of fat(P < 0.01).The best-fit equation to predict SID of fat was SID AEE = 102.75-0.15 × LSFA-0.74 × C18:0-0.03 × C18:1(Adjusted coefficient of determination = 0.88,P < 0.01).Conclusions:When calculating the SID of fat,the EE content of the samples can be analyzed using the direct extraction method,whereas the acid hydrolysis procedure should be used to determine the AID of fat.Fat digestibility of dietary oils was affected by their fatty acid composition,especially by the contents of C16:0,LSFA and U/S.展开更多
The staggered distribution of joints and fissures in space constitutes the weak part of any rock mass.The identification of rock mass structural planes and the extraction of characteristic parameters are the basis of ...The staggered distribution of joints and fissures in space constitutes the weak part of any rock mass.The identification of rock mass structural planes and the extraction of characteristic parameters are the basis of rock-mass integrity evaluation,which is very important for analysis of slope stability.The laser scanning technique can be used to acquire the coordinate information pertaining to each point of the structural plane,but large amount of point cloud data,uneven density distribution,and noise point interference make the identification efficiency and accuracy of different types of structural planes limited by point cloud data analysis technology.A new point cloud identification and segmentation algorithm for rock mass structural surfaces is proposed.Based on the distribution states of the original point cloud in different neighborhoods in space,the point clouds are characterized by multi-dimensional eigenvalues and calculated by the robust randomized Hough transform(RRHT).The normal vector difference and the final eigenvalue are proposed for characteristic distinction,and the identification of rock mass structural surfaces is completed through regional growth,which strengthens the difference expression of point clouds.In addition,nearest Voxel downsampling is also introduced in the RRHT calculation,which further reduces the number of sources of neighborhood noises,thereby improving the accuracy and stability of the calculation.The advantages of the method have been verified by laboratory models.The results showed that the proposed method can better achieve the segmentation and statistics of structural planes with interfaces and sharp boundaries.The method works well in the identification of joints,fissures,and other structural planes on Mangshezhai slope in the Three Gorges Reservoir area,China.It can provide a stable and effective technique for the identification and segmentation of rock mass structural planes,which is beneficial in engineering practice.展开更多
The recycling of carbon fibers and protection from unwanted microwave radiation are two important environmental issues that need to be addressed in modern society.Herein,branched carbon nanofibers(CNFs)were grown in-s...The recycling of carbon fibers and protection from unwanted microwave radiation are two important environmental issues that need to be addressed in modern society.Herein,branched carbon nanofibers(CNFs)were grown in-situ on recycled carbon fibers(RCFs)through the chemical vapor deposition method using nickel as catalysts and thiophene as aided-catalysts.The effect of thiophene on the growth morphology of CNFs was investigated.Correspondingly,branched CNFs-RCFs and straight CNFs-RCFs were respectively obtained in the presence and absence of thiophene.The microstructure and electromagnetic behaviour investigations have shown that the branched CNFs possess a typical multi-branched structure,with more defects,pores and a larger specific surface area than the straight CNFs,which lead to better impedance matching and adequate dielectric loss ability for the branched CNFs-RCFs.The reflection loss(RL)results show that the branched CNFs-RCFs exhibit an optimum RL of -23.6 dB at 1.5 mm and a best effective absorption bandwidth(EAB)of 7.5 GHz at 2.0 mm.This research provides an innovative microwave absorbing material with adequate absorbing strength and outstanding EAB,while also promoting the sustainable reuse of the RCFs resources.展开更多
Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of cl...Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of climate change on Frost-free days in winter is distinctive. The average annual temperature is going upward but the extreme increase is in the winter temperature. Winter average temperature is going up by about 2˚C. However, extreme daily minimum temperature is going up by more than 3˚C. This climate effect has a great impact on the nature of precipitation and length of frost-free days. The snowfall over winter months is decreasing and the rainfall is increasing. However, the number of frost-free days during late fall months, early winter months, late winter months and early spring months are increasing. This result reveals an increase in length of the growing season. This research focuses on the effect of change in climatic variables on Frost-free days in Southern Ontario. Therefore, special attention should be given to the effect of change in climate Frost-free conditions on length of crop growing in winter season for potential investigation.展开更多
Zimbabwe makes big gains in agricultural yields on the back of Chinese cooperation For the first time in 56 years, Zimbabwe was able to produce sufflcient wheat for its population,and in the process, became the only A...Zimbabwe makes big gains in agricultural yields on the back of Chinese cooperation For the first time in 56 years, Zimbabwe was able to produce sufflcient wheat for its population,and in the process, became the only African country to do so.According to the country’s Cluster Agricultural Development Services, Zimbabwe achieved a milestone in wheat production by harvesting 375,000tonnes of the grain in 2022.展开更多
The climate change in Alaska has caused earlier spring snowmelt and the growing season expanded. However, the effect of climate change on crop phenological stages, heading (BBCH 55) and maturity (BBCH 85), is unknown....The climate change in Alaska has caused earlier spring snowmelt and the growing season expanded. However, the effect of climate change on crop phenological stages, heading (BBCH 55) and maturity (BBCH 85), is unknown. In this study, the trends of growing-season length (GSL), phenological stages of crops and climatic parameters, and the correlations between climatic parameters and the phenological stages were analyzed using the climate data and crop data over the period of 1978 to 2016. The longer GSL was found in Fairbanks (64.83<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span></span>N, 147.77<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span></span>W) and in Delta Junction (64.05<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>N, 145.60<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>W) but not in Palmer (61.60<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>N, 149.11<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>W). Sowing dates did not change significantly in three locations. The decreasing trends of heading and maturity of crops were observed but varied with location. Heading of barley and oat significantly advanced 3 and 3.1 d decade<sup>-1</sup>, respectively from 1989 to 2016 in Fairbanks while no change of heading was observed in Delta Junction and Palmer. Maturity of barley, oat and wheat significantly advanced 2.6, 3.8 and 3.9 d decade<sup>-1</sup>, respectively from 1978 to 2016 in Fairbanks (<em>P</em> < 0.05);maturity of oat and wheat significantly advanced 4.4 and 3.4 d decade<sup>-1</sup> from 1978 to 2015, respectively in Delta Junction (<em>P</em> < 0.05). The increasing temperature trends and decreasing precipitation trends were found in Fairbanks and Delta Junction but varied with phenological stages of crops. Sowing was more important for heading than for maturity of crops. The effect of climate change on heading was less important than that on maturity. Earlier maturity of crops in Fairbanks may be attributed to increased temperatures, that in Delta Junction to both increased minimum temperature and decreased precipitation and that in Palmer to temperature and precipitation.展开更多
Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to val...Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to validate the NE of these four ingredients using pig growth performance.Methods: In Exp.1, 24 barrows(initial BW = 36.4 ± 1.6 kg) were allotted to 1 of 4 diets which included a corn basal diet,a corn-soybean meal basal diet and two rapeseed meal diets containing 20% EP-RSM(9.5% ether extract) or SE-RSM(1.1% ether extract) substituted for corn and soybean meal. The design allowed the calculation of NE values of corn,soybean meal and rapeseed meals according to the difference method. In Exp.2, 175 growing pigs(initial BW = 36.0± 5.2 kg) were fed 1 of 5 diets for 28 d, with five pigs per pen and seven replications(pens) per treatment in order to validate the measured energy values. Diets were a corn-soybean meal diet and four diets including 10% or 20% EP-RSM and 10% or 20% SE-RSM.Results: The NE of corn, soybean meal, EP-RSM and SE-RSM were 12.46, 11.34, 11.71 and 8.83 MJ/kg DM, respectively. The NE to ME ratio of corn(78%) was similar to tabular values, however, the NE to ME ratios of soybean meal(70%) and rapeseed meal(76%) were greater than tabular values. The greater NE value in EP-RSM than in SE-RSM is consistent with its higher EE content. Increasing EP-RSM or SE-RSM did not affect the growth performance of pigs and the caloric efficiency of NE was comparable for al diets.Conclusions: The NE of EP-RSM was similar to soybean meal, and both were greater than SE-RSM. The DE, ME and NE values measured in Exp.1 are confirmed by results of Exp. 2 with comparable caloric efficiencies of DE, ME or NE for all diets.展开更多
Nanomaterials based on nickel foam(NF) have been widely applied in energy conversion and storage field.Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable de...Nanomaterials based on nickel foam(NF) have been widely applied in energy conversion and storage field.Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable developments.Herein,we report a fast,simple,and low-cost synthesis method of nanomaterials based on NF by Joule-heating and water soaking treatment.Thin carbon-coated CoS on NF(NF-C/CoS) was synthesized by Joule-heating for a few seconds with rapid cooling.And then,NF-C/CoS/NiOOH with core-shell heterostructure was fabricated by soaking treatment of NF-C/CoS in water on which NiOOH nanosheets grew spontaneously.The formation mechanism is proposed that the coordination complex precursor converts into C/CoS on NF driven by Joule-heating,and the nickel on the surface of NF is activated to form metastable nickel simultaneously.The metastable nickel reacting with water leads to the formation of NiOOH,and the induction of CoS makes NiOOH grow continuously.This synthesis technology provides a new route to manufacture NF-based nanostructures,and the as-fabricated NF-C/CoS/NiOOH exhibits great potential as electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction.展开更多
This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,s...This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,spatial autocorrelation,and the geographically weighted regression(GWR)model were used to conduct the analysis.The conclusions were as follows:first,the overall efficiency of green development of the Xuzhou Metropolitan Area decreased,the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency.Second,the counties with high-efficiency green development were distributed along the coast,and along the routes of the Beijing-Shanghai and the Eastern Longhai railways.A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency.Third,regarding spatial correlation and green development efficiency,the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu,whereas the Low-Low type counties were concentrated in the external,marginal parts of the metropolitan area.Fourth,the major factors(ranked in decreasing order of impact)influencing green development efficiency were innovation,government regulations,the economic development level,energy consumption,and industrial structure.These factors exerted their influence to varying extents;the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions.展开更多
Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn...Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set(n = 88) and a validation set(n = 29). The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez(J Anim Sci. 71:3389–98,1993). The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square(MPLS) regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results: The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration(RSQ_(cal)), cross-validation(R^2_(CV)), and validation(RSQ_v) were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQ_(cal), R^2_(CV), and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME(RPD_v= 2.38, < 2.50), the other three equations built from actually determined energy and calculated DE produced good prediction performance(RPD_vranging from 2.53 to 2.69, > 2.50) when applied to validation samples.Conclusion: These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.展开更多
Background: Compared with oral antibiotics(primarily disrupt foregut microbiota), the present study used antibiotics with ileum terminal infusion to disrupt the hindgut microbiota, and investigated the changes in spec...Background: Compared with oral antibiotics(primarily disrupt foregut microbiota), the present study used antibiotics with ileum terminal infusion to disrupt the hindgut microbiota, and investigated the changes in specific bacterial composition and immune indexes in the jejunum and colon, and serum of growing pigs. Twelve barrows(45 d of age, 12.08 ± 0.28 kg) fitted with a T-cannula at the terminal ileum, were randomly assigned to two groups and infused either saline without antibiotics(Control) or with antibiotics(Antibiotic) at the terminal ileum. After 25 d experiment, all pigs were euthanized for analyzing bacterial composition and immune status.Results: Ileum terminal antibiotic infusion(ITAI) altered dominant bacteria counts, with a decrease in Bifidobacterium, Clostridium cluster IV and Clostridium cluster IV in the colon(P < 0.05), and an increase in Escherichia coli in the jejunum(P < 0.05). ITAI decreased(P < 0.05) short-chain fatty acids concentrations in the colon. ITAI decreased interleukin-8(IL-8), IL-10 and secretory immunoglobulin A(sIgA) concentrations, and down-regulated IL-10, Mucin-1(MUC1), Mucin-2(MUC2) and zonula occludens-1(ZO-1) mRNA expression in the colonic mucosa(P < 0.05). In the jejunal mucosa, ITAI decreased interferon-γ(IFN-γ), tumor necrosis factor-α(TNF-α), s IgA and IgG levels together with down-regulation of IFN-γ, TNF-α, MUC2 and ZO-1 mRNA expression(P < 0.05). Furthermore, ITAI decreased IL-10, INF-γ, TNF-α, IgA and IgG concentrations in serum(P < 0.05). Correlation analysis revealed that the change in intestinal microbiota was correlated with alterations of Ig and cytokines.Conclusions: ITAI affected jejunal and colonic specific bacteria counts, and altered some immune markers levels in the jejunal and colonic mucosa and serum. These findings implicate the potential contribution of hindgut bacteria to immune response in the intestinal mucosa and serum of growing pigs.展开更多
[Objective] The paper was to investigate effects of pelleted total mixed ration on production performance and serum biochemical index of growing Hainan black goats.[Method] Twenty-four growing Hainan black goats with ...[Objective] The paper was to investigate effects of pelleted total mixed ration on production performance and serum biochemical index of growing Hainan black goats.[Method] Twenty-four growing Hainan black goats with the same genetic backgrounds and similar initial weight of(10.05±0.049) kg were randomly assigned into two treatments, and supplied with Juncao + concentrate(control group), pelleted total mixed ration(experimental group), respectively. The trial lasted 50 d.[Result] The final weight, daily gain and feed intake of experimental group were significantly higher than those of control group(P<0.05), but the feed/gain ratio of experimental group was markedly lower than that of control group(P<0.05). Compared with the control group, the gross profit of experimental group significantly increased( P <0.05).[Conclusion] Pelleted total mixed ration led to better production performance of growing Hainan black goat.展开更多
Background: Determination of the endogenous loss of fat(ELF) is used to adjust for the estimation of true total tract digestibility(TTTD) of fat in diets and ingredients.Any factor which affected ELF may further affec...Background: Determination of the endogenous loss of fat(ELF) is used to adjust for the estimation of true total tract digestibility(TTTD) of fat in diets and ingredients.Any factor which affected ELF may further affect the digestibility of fat,including sources and concentrations of fat and fiber in the diet.There are some reports of determining the ELF using regression methods based on different levels of fat intake,while reports on effects of dietary fiber content and different fiber-rich ingredients in pig diets on ELF are very limited.Therefore,the objective of this study was to determine the effects of dietary fiber content and different fiber-rich ingredients on endogenous losses of fat and fatty acids at the end of ileum and throughout the entire intestinal tract in growing pigs.Methods: In Exp.1,the effect of fiber content on endogenous loss of fat was determined using six growing pigs(Duroc × Landrace × Yorkshire;27.6 ± 2.4 kg),fitted with a T-cannula at the end of ileum.The experimental design was a 6 × 6 complete Latin square design with six periods of feeding and six diets.The six experimental fat-free diets were formulated to include graded levels of neutral detergent fiber(NDF)(0,40,80,120,160 and 200 g/kg) and soybean hull(SH) was the only fiber source,providing 0,75,150,225,300 and 375 g/kg,respectively.Chromic oxide was included at4 g/kg in all diets as an indigestible marker.In Exp.2,six crossbred growing barrows(27.6 ± 1.6 kg) were used and the experimental design was the same as for Exp.1.The six fat-free diets were formulated to include six common fiber-rich ingredients and the concentration of NDF was 100 g/kg.The six fiber-rich ingredients were defatted rice bran(DRB),sugar beet pulp(SBP),rice hull(RH),corn germ meal(CGM),SH and wheat bran(WB) and they were fed at represented250,270,145,250,170 and 280 g/kg in the diet,respectively.Results: In Exp.1,the endogenous loss of fatty acids profile did not change as dietary NDF increased in growing pigs.The endogenous losses of fat,C16:0,C18:0,C18:1,C18:2,total unsaturated fatty acids(UFA) and total saturated fatty acids(SFA) in growing pigs at the end of ileum and throughout the entire intestinal tract increased linearly as NDF content of diets increased.The endogenous losses of fat,as well as C16:0 and C18:0 throughout the entire intestinal tract also increased quadratically as NDF content of diets increased.The ELF increased from 0.71 to 3.14 g/kg of dry matter intake(DMI) and 0.56 to 8.21 g/kg DMI at the end of ileum and throughout the entire intestinal tract in growing pigs,respectively.The ELF occurred in the hindgut except for the growing pigs fed 0 and 4% NDF in their diets.The endogenous losses of C16:0 and UFA occurred primarily in the upper regions of the gut and the greatest endogenous losses of C18:0 occurred in the hindgut.The endogenous losses of fat,individual SFA and total SFA throughout the entire intestinal tract were much greater than that at the end of ileum.However,the endogenous losses of individual UFA and total UFA were less throughout the intestinal tract than at the end of ileum.In Exp.2,the endogenous losses of fat at the end of ileum were greater in growing pigs fed CGM or WB diets.The endogenous loss of fatty acids profile changed to a slight degree at the end of ileum that the endogenous loss of UFA(particularly C18:1 and C18:2) in growing pigs fed CGM or WB diets were greater(P < 0.01) than that for the other four diets.The greatest(P < 0.01) endogenous loss of SFA(particularly C18:0) was in growing pigs fed the RH diet.The endogenous losses of fat,C16:0,C18:0 and SFA over the entire intestinal tract were much greater in growing pigs fed CGM or WB diets,whereas the lowest values were in growing pigs fed DRB diet.The ELF at the end of ileum in growing pigs fed CGM or WB diets were 3.50 or 4.17 g/kg DMI,respectively,and the ELF over the entire intestinal tract was 7.23 or 7.38 g/kg DMI.The contribution in percentage of ELF in the upper gut was greater than that in the hindgut of growing pigs fed DRB and RH diets,while the ELF in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.On the whole,the endogenous losses of C18:1 and C18:2 throughout the entire intestinal tract in growing pigs fed the six fiber-rich ingredients diets were less than losses at the end of ileum,whereas the endogenous loss of fat,C16:0,C18:0 and SFA were greater throughout the intestinal tract than at the end of ileum.Conclusion: The profile of loss in endogenous fatty acids did not change as dietary NDF increased in growing pigs and the endogenous losses of fatty acids(C16:0,C18:0,C18:1 and C18:2) fat,UFA and SFA increased linearly as NDF content increased in the diets of pigs.The endogenous losses of fat or fatty acids at the end of ileum were greater in growing pigs fed RH,CGM or WB diets.The endogenous losses of fat,fatty acids(C16:0 and C18:0) and SFA were greater over the entire intestinal tract in pigs fed CGM or WB diet,while these values were the lowest in growing pigs fed the DRB diet.The contribution in percentage losses of fat in the upper gut were greater than in the hindgut of growing pigs fed DRB and RH diets,while the contribution of losses of fat in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.In addition,the endogenous loss of individual or total UFA was less over the entire intestinal tract of growing pigs fed fiber diets than that at the end of ileum,and the greatest endogenous losses of fat,individual or total SFA were over the entire intestinal tract.Therefore,differences in fiber content and the nature of fiber-rich ingredients in diets of pigs have different effects to the endogenous losses of fat or fatty acids.Considering the requirement of fat or fatty acids of pigs,careful attention must be paid that the endogenous losses of fat and fatty acids when fiber ingredients are used in diets of pigs.展开更多
Background: Basal ileal endogenous amino acid(AA) losses(IAA_(end)) and standardized ileal digestibility(SID) values of cereal grains, such as barley, are apparently underestimated when determined according to the nit...Background: Basal ileal endogenous amino acid(AA) losses(IAA_(end)) and standardized ileal digestibility(SID) values of cereal grains, such as barley, are apparently underestimated when determined according to the nitrogen(N)-free method. Regression analysis between the dietary apparent ileal digestible content(c AID) and total crude protein(CP) and AA can be considered as alternative approach to obtain more accurate values for IAA_(end)and SID of AA in cereal grains.Methods: Eight hulled barley genotypes were used, with barley being the only source of CP and AA in the assay diets. The diets contained 95 % as-fed of these eight barley genotypes each, ranging in CP content between 109.1 and 123.8 g/kg dry matter(DM). Nine ileally T-cannulated barrows, average body weight(BW) 30 ± 2 kg, were allotted to a row-column design comprising eight periods with 6 d each and nine pigs. On d 5 and the night of d 6 of every period, ileal digesta were collected for a total of 12 h. The IAA_(end) and the SID were determined by linear regression analysis between c AID and total dietary CP and AA.Results: There exist linear relationships between cA ID and total CP and AA(P < 0.001). The IAA_(end) of CP, Lys, Met, Thr and Trp amounted to 35.34, 1.08, 0.25, 1.02 and 0.38 g/kg DM intake(DMI), respectively, which are greater compared to average IAA_(end) determined previously under N-free feeding conditions. The SID of CP, Lys, Met, Thr and Trp was 90,79, 85, 79 and 86 %, respectively, and was greater when compared to tabulated values. Moreover, these SID values were greater than those reported in literature, based on correction of apparent ileal digestibility(AID) of CP and AA for their IAA_(end)values. Summarized, the results of the present regression analysis indicate greater IAA_(end)in barley-based diets compared to those obtained by N-free feeding.Conclusions: For low-protein feed ingredients like barley the regression method may be preferred over correction of AID values for their IAA_(end)determined under N-free feeding conditions, as intercepts and slopes of the linear regression equations between cA ID and total dietary CP and AA provide direct estimates of IAA_(end)and SID of CP and AA in the presence of the assay feed ingredient.展开更多
Steganography technology has been widely used in data transmission with secret information.However,the existing steganography has the disadvantages of low hidden information capacity,poor visual effect of cover images...Steganography technology has been widely used in data transmission with secret information.However,the existing steganography has the disadvantages of low hidden information capacity,poor visual effect of cover images,and is hard to guarantee security.To solve these problems,steganography using reversible texture synthesis based on seeded region growing and LSB is proposed.Secret information is embedded in the process of synthesizing texture image from the existing natural texture.Firstly,we refine the visual effect.Abnormality of synthetic texture cannot be fully prevented if no approach of controlling visual effect is applied in the process of generating synthetic texture.We use seeded region growing algorithm to ensure texture’s similar local appearance.Secondly,the size and capacity of image can be decreased by introducing the information segmentation,because the capacity of the secret information is proportional to the size of the synthetic texture.Thirdly,enhanced security is also a contribution in this research,because our method does not need to transmit parameters for secret information extraction.LSB is used to embed these parameters in the synthetic texture.展开更多
Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by c...Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by classical supplementation technique and principles of diet dilution technique as applied with “Goettingen approach”. During the starter period (1 - 21 d), a growth study with male meat type chicken (Ross 308) was conducted making use of five graded dietary Lys-levels (3 repetition boxes with 3 birds/box). L-Lys×HCl was gradually added to a diet based on wheat, soybean protein concentrate, wheat gluten and fishmeal to yield 80%, 87.5%, 95%, 102.5% and 110% of the expected requirement level (13 g Lys/kg as fed). Diets were iso-energetic (12.8 MJME/kg) and iso-nitrogenous (21.65% crude protein). Birds were fed on free choice level also to assess the feed intake (FI) effects as important factor on traditional response criteria. Analyzed body composition at start and end of the growth study yielded N deposition (ND) data for further data assessment using exponential approximations depending on dietary Lys content or observed Lys intake. The results indicated significant differences (p < 0.05) in response on body weight gain (BWG) and observed dietary protein quality with unexpected consequences for the derived Lys requirement data. According to the independent variable (Lys in % of diet versus daily Lys intake) and aimed level of daily ND, the needed in-feed content of Lys varied between 1.24% and 1.46%. Application of the exponential modelling by “Goettingen approach” overcame these misleading conclusions by modelling the relationship between required Lys intake and observed response data (BWG, ND) taking also into account the expected real feed intake to formulate the needed in-feed concentration.展开更多
Considering that growing hierarchical self-organizing map(GHSOM) ignores the influence of individual component in sample vector analysis, and its accurate rate in detecting unknown network attacks is relatively lower,...Considering that growing hierarchical self-organizing map(GHSOM) ignores the influence of individual component in sample vector analysis, and its accurate rate in detecting unknown network attacks is relatively lower, an improved GHSOM method combined with mutual information is proposed. After theoretical analysis, experiments are conducted to illustrate the effectiveness of the proposed method by accurately clustering the input data. Based on different clusters, the complex relationship within the data can be revealed effectively.展开更多
The grain growing dynamics including the growing process, the growing exponent and the growing activation energy is obtained for the MgO-CaO composite ceramics with the additions of Fe2O3, CeO2 and/or ZrO2 as fluxes b...The grain growing dynamics including the growing process, the growing exponent and the growing activation energy is obtained for the MgO-CaO composite ceramics with the additions of Fe2O3, CeO2 and/or ZrO2 as fluxes by measuring the size of grains with the method of Straight Line Across. The results show that all of the additions, in which Fe2O3 is the strongest, have notable effects on the grain growing dynamics by reducing the growing activation energy and promoting the grain growing. The research gives a good reference for the additions of fluxes to the matrix of ceramic filter.展开更多
Background: The aim of this study was to investigate the intergeneric transfer of vancomycin resistance gene vanA between probiotic enterococci in the fermentation progress of soybean meal and in the digestive tract o...Background: The aim of this study was to investigate the intergeneric transfer of vancomycin resistance gene vanA between probiotic enterococci in the fermentation progress of soybean meal and in the digestive tract of growing pigs.One vanA genotype vancomycin resistant E.faecium strain,Efm4,and one chloramphenicol-resistant E.faecalis strain,Efs2,were isolated from twenty-nine probiotic basis feed material/additive samples.For in vitro conjugation,Efm4 and Efs2 were used as starter to ferment soybean meal.For in vivo conjugation,thirty growing pigs were randomly assigned to five groups(n = 6),treated with a basic diet,or supplemented with 10% fermented soybean meal,1% Efm4,5% Efs2 or a combination of 1% Efm4 + 5% Efs2 for 7 d,respectively.Fecal samples of pigs in each group were collected daily for the isolation and dynamic analysis of Efm4,Efs2 and transconjugants.The sequence types(STs) of Efm4,Efs2 and transconjugants were analyzed by multilocus sequence typing(MLST).The vanA harboring plasmid in Efm4 and transconjugants was analyzed by S1-pulsed field gel electrophoresis(PFGE)and further verified by multiple alignments.Results: The results showed that,in FSBM,transconjugants were detected 1 h after the fermentation,with a conjugation frequency of ~ 10^-3 transconjugants/recipient.Transconjugants proliferated with Efm4 and Efs2 in the first 8 h and maintained steadily for 10 d till the end of the experiment.Additionally,in vivo experiment showed that transcojugants were recovered in one of six pigs in both FSBM and Efm4 + Efs2 groups,with conjugation frequency of ~ 10^-5 and ~ 10^-4,respectively.MLST revealed the ST of Efm4,Efs2 and transconjugants was ST1014,ST69 and ST69,respectively.S1-PFGE confirmed the existence of the vanA-harboring,142,988-bp plasmid,which was also a multi-drug resistant plasmid containing Tn1546-like transposon.Conclusions: The findings revealed the potential safety hazard existing in the commercial probiotic enterococci in China,because the horizontal transfer from farm to fork could potentially pose a safety risk to the public.展开更多
文摘Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent diggers that can move in unstructured environments and navigate past barriers.Furthermore,root growth has a high energy efficiency since it penetrates the soil at its tip,adding new material without displacing the already grown portion,minimizing the energy dissipation due to friction and lowering the inertia.A robot inspired by the growth of roots could be used in search and rescue or environmental monitoring.The design of a soft robot inspired by root growth is presented in this article.The robot body consists of a cylindrical plastic membrane folded inside itself.The robot body is inflated,and its tip is everted,expanding its length as air is blown from the base.Velcro straps are placed on the membrane’s exterior surface to keep it folded.The head is positioned inside the tip,which houses the mechanism that controls the growth direction.It consists of housing for two balloons that are selectively inflated,and their expansion applies pressure on the exterior surface,opening the Velcro straps and determining the growth direction.The robot was constructed,and a kinematic model of its motion in the plane was created and compared with experimental data.The error in predicting the turning angle is only 5%,and the resulting predicted position differs on average by 55 mm on a total length of 850 mm.
基金supported by National Natural Science Foundation of China(31972597)National Key R&D Program of China(2021YFD1300202)S&T Program of Hebei(199A7310H).
文摘Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.Methods:Twenty-two barrows(initial body weight:32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum,and allotted to 1 of 11 experimental diets in a 4-period Youden Square design.A fat-free diet was formulated using cornstarch,soy protein isolate and sucrose.Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch.All diets contained 26% sugar beet pulp and 0.40% chromic oxide.Results:The endogenous loss of ether extract(EE) was lower than that of acid-hydrolyzed fat(AEE;P < 0.01).There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources(P < 0.05).The SID of AEE for palm oil was lower than that of sunflower oil,corn oil,canola oil,rice oil and flaxseed oil(P < 0.01).The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%.Although the AID of EE was greater than that of AEE(P < 0.01),there was no significant difference in SID of EE and AEE except for palm oil.The ratio of unsaturated to saturated fatty acids(U/S) had a positive correlation with SID of fat(P < 0.05),whereas C16:0 and long chain saturated fatty acids(LSFA) were significant negatively correlated with SID of fat(P < 0.01).The best-fit equation to predict SID of fat was SID AEE = 102.75-0.15 × LSFA-0.74 × C18:0-0.03 × C18:1(Adjusted coefficient of determination = 0.88,P < 0.01).Conclusions:When calculating the SID of fat,the EE content of the samples can be analyzed using the direct extraction method,whereas the acid hydrolysis procedure should be used to determine the AID of fat.Fat digestibility of dietary oils was affected by their fatty acid composition,especially by the contents of C16:0,LSFA and U/S.
基金the National Natural Science Foundation of China(51909136)the Open Research Fund of Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University),Ministry of Education,Grant No.2022KDZ21Fund of National Major Water Conservancy Project Construction(0001212022CC60001)。
文摘The staggered distribution of joints and fissures in space constitutes the weak part of any rock mass.The identification of rock mass structural planes and the extraction of characteristic parameters are the basis of rock-mass integrity evaluation,which is very important for analysis of slope stability.The laser scanning technique can be used to acquire the coordinate information pertaining to each point of the structural plane,but large amount of point cloud data,uneven density distribution,and noise point interference make the identification efficiency and accuracy of different types of structural planes limited by point cloud data analysis technology.A new point cloud identification and segmentation algorithm for rock mass structural surfaces is proposed.Based on the distribution states of the original point cloud in different neighborhoods in space,the point clouds are characterized by multi-dimensional eigenvalues and calculated by the robust randomized Hough transform(RRHT).The normal vector difference and the final eigenvalue are proposed for characteristic distinction,and the identification of rock mass structural surfaces is completed through regional growth,which strengthens the difference expression of point clouds.In addition,nearest Voxel downsampling is also introduced in the RRHT calculation,which further reduces the number of sources of neighborhood noises,thereby improving the accuracy and stability of the calculation.The advantages of the method have been verified by laboratory models.The results showed that the proposed method can better achieve the segmentation and statistics of structural planes with interfaces and sharp boundaries.The method works well in the identification of joints,fissures,and other structural planes on Mangshezhai slope in the Three Gorges Reservoir area,China.It can provide a stable and effective technique for the identification and segmentation of rock mass structural planes,which is beneficial in engineering practice.
基金supported by the Natural Science Foundation of Hunan Province,China(2021JJ40175)the Science Research Project of Hunan Provincial Department of Education(20C0630).
文摘The recycling of carbon fibers and protection from unwanted microwave radiation are two important environmental issues that need to be addressed in modern society.Herein,branched carbon nanofibers(CNFs)were grown in-situ on recycled carbon fibers(RCFs)through the chemical vapor deposition method using nickel as catalysts and thiophene as aided-catalysts.The effect of thiophene on the growth morphology of CNFs was investigated.Correspondingly,branched CNFs-RCFs and straight CNFs-RCFs were respectively obtained in the presence and absence of thiophene.The microstructure and electromagnetic behaviour investigations have shown that the branched CNFs possess a typical multi-branched structure,with more defects,pores and a larger specific surface area than the straight CNFs,which lead to better impedance matching and adequate dielectric loss ability for the branched CNFs-RCFs.The reflection loss(RL)results show that the branched CNFs-RCFs exhibit an optimum RL of -23.6 dB at 1.5 mm and a best effective absorption bandwidth(EAB)of 7.5 GHz at 2.0 mm.This research provides an innovative microwave absorbing material with adequate absorbing strength and outstanding EAB,while also promoting the sustainable reuse of the RCFs resources.
文摘Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of climate change on Frost-free days in winter is distinctive. The average annual temperature is going upward but the extreme increase is in the winter temperature. Winter average temperature is going up by about 2˚C. However, extreme daily minimum temperature is going up by more than 3˚C. This climate effect has a great impact on the nature of precipitation and length of frost-free days. The snowfall over winter months is decreasing and the rainfall is increasing. However, the number of frost-free days during late fall months, early winter months, late winter months and early spring months are increasing. This result reveals an increase in length of the growing season. This research focuses on the effect of change in climatic variables on Frost-free days in Southern Ontario. Therefore, special attention should be given to the effect of change in climate Frost-free conditions on length of crop growing in winter season for potential investigation.
文摘Zimbabwe makes big gains in agricultural yields on the back of Chinese cooperation For the first time in 56 years, Zimbabwe was able to produce sufflcient wheat for its population,and in the process, became the only African country to do so.According to the country’s Cluster Agricultural Development Services, Zimbabwe achieved a milestone in wheat production by harvesting 375,000tonnes of the grain in 2022.
文摘The climate change in Alaska has caused earlier spring snowmelt and the growing season expanded. However, the effect of climate change on crop phenological stages, heading (BBCH 55) and maturity (BBCH 85), is unknown. In this study, the trends of growing-season length (GSL), phenological stages of crops and climatic parameters, and the correlations between climatic parameters and the phenological stages were analyzed using the climate data and crop data over the period of 1978 to 2016. The longer GSL was found in Fairbanks (64.83<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span></span>N, 147.77<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span></span>W) and in Delta Junction (64.05<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>N, 145.60<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>W) but not in Palmer (61.60<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>N, 149.11<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span></span>W). Sowing dates did not change significantly in three locations. The decreasing trends of heading and maturity of crops were observed but varied with location. Heading of barley and oat significantly advanced 3 and 3.1 d decade<sup>-1</sup>, respectively from 1989 to 2016 in Fairbanks while no change of heading was observed in Delta Junction and Palmer. Maturity of barley, oat and wheat significantly advanced 2.6, 3.8 and 3.9 d decade<sup>-1</sup>, respectively from 1978 to 2016 in Fairbanks (<em>P</em> < 0.05);maturity of oat and wheat significantly advanced 4.4 and 3.4 d decade<sup>-1</sup> from 1978 to 2015, respectively in Delta Junction (<em>P</em> < 0.05). The increasing temperature trends and decreasing precipitation trends were found in Fairbanks and Delta Junction but varied with phenological stages of crops. Sowing was more important for heading than for maturity of crops. The effect of climate change on heading was less important than that on maturity. Earlier maturity of crops in Fairbanks may be attributed to increased temperatures, that in Delta Junction to both increased minimum temperature and decreased precipitation and that in Palmer to temperature and precipitation.
基金supported by the Modern Agricultural Industry Technology System(CARS-36)Developing key equipment for digital management and monitoring environment in animal production(2013AA10230602)+1 种基金National Natural Science Foundation of China(31372317)the 111 Project(B16044)
文摘Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to validate the NE of these four ingredients using pig growth performance.Methods: In Exp.1, 24 barrows(initial BW = 36.4 ± 1.6 kg) were allotted to 1 of 4 diets which included a corn basal diet,a corn-soybean meal basal diet and two rapeseed meal diets containing 20% EP-RSM(9.5% ether extract) or SE-RSM(1.1% ether extract) substituted for corn and soybean meal. The design allowed the calculation of NE values of corn,soybean meal and rapeseed meals according to the difference method. In Exp.2, 175 growing pigs(initial BW = 36.0± 5.2 kg) were fed 1 of 5 diets for 28 d, with five pigs per pen and seven replications(pens) per treatment in order to validate the measured energy values. Diets were a corn-soybean meal diet and four diets including 10% or 20% EP-RSM and 10% or 20% SE-RSM.Results: The NE of corn, soybean meal, EP-RSM and SE-RSM were 12.46, 11.34, 11.71 and 8.83 MJ/kg DM, respectively. The NE to ME ratio of corn(78%) was similar to tabular values, however, the NE to ME ratios of soybean meal(70%) and rapeseed meal(76%) were greater than tabular values. The greater NE value in EP-RSM than in SE-RSM is consistent with its higher EE content. Increasing EP-RSM or SE-RSM did not affect the growth performance of pigs and the caloric efficiency of NE was comparable for al diets.Conclusions: The NE of EP-RSM was similar to soybean meal, and both were greater than SE-RSM. The DE, ME and NE values measured in Exp.1 are confirmed by results of Exp. 2 with comparable caloric efficiencies of DE, ME or NE for all diets.
基金supported by the National Natural Science Foundation of China (Nos. 91963113, 51701139, and U1601216)。
文摘Nanomaterials based on nickel foam(NF) have been widely applied in energy conversion and storage field.Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable developments.Herein,we report a fast,simple,and low-cost synthesis method of nanomaterials based on NF by Joule-heating and water soaking treatment.Thin carbon-coated CoS on NF(NF-C/CoS) was synthesized by Joule-heating for a few seconds with rapid cooling.And then,NF-C/CoS/NiOOH with core-shell heterostructure was fabricated by soaking treatment of NF-C/CoS in water on which NiOOH nanosheets grew spontaneously.The formation mechanism is proposed that the coordination complex precursor converts into C/CoS on NF driven by Joule-heating,and the nickel on the surface of NF is activated to form metastable nickel simultaneously.The metastable nickel reacting with water leads to the formation of NiOOH,and the induction of CoS makes NiOOH grow continuously.This synthesis technology provides a new route to manufacture NF-based nanostructures,and the as-fabricated NF-C/CoS/NiOOH exhibits great potential as electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction.
基金Under the auspices of the National Natural Science Foundation of China(No.41671123,41971158,41671122)Major Project of Philosophy and Social Science Research of Jiangsu Universities(No.2018SJZDA010).
文摘This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,spatial autocorrelation,and the geographically weighted regression(GWR)model were used to conduct the analysis.The conclusions were as follows:first,the overall efficiency of green development of the Xuzhou Metropolitan Area decreased,the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency.Second,the counties with high-efficiency green development were distributed along the coast,and along the routes of the Beijing-Shanghai and the Eastern Longhai railways.A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency.Third,regarding spatial correlation and green development efficiency,the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu,whereas the Low-Low type counties were concentrated in the external,marginal parts of the metropolitan area.Fourth,the major factors(ranked in decreasing order of impact)influencing green development efficiency were innovation,government regulations,the economic development level,energy consumption,and industrial structure.These factors exerted their influence to varying extents;the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions.
基金financially supported by China Special Public Sector Fund in Agriculture(200903006)The collection of data and analysis were funded by National Key Technology Research and Development Program(2011BAD26B0404)The interpretation of data and writing of the manuscript were supported by 111 Project(B16044)
文摘Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set(n = 88) and a validation set(n = 29). The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez(J Anim Sci. 71:3389–98,1993). The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square(MPLS) regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results: The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration(RSQ_(cal)), cross-validation(R^2_(CV)), and validation(RSQ_v) were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQ_(cal), R^2_(CV), and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME(RPD_v= 2.38, < 2.50), the other three equations built from actually determined energy and calculated DE produced good prediction performance(RPD_vranging from 2.53 to 2.69, > 2.50) when applied to validation samples.Conclusion: These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.
基金supported by Natural Science Foundation of China(31430082)National Key Basic Research Program of China,973 Program(2013CB127300)
文摘Background: Compared with oral antibiotics(primarily disrupt foregut microbiota), the present study used antibiotics with ileum terminal infusion to disrupt the hindgut microbiota, and investigated the changes in specific bacterial composition and immune indexes in the jejunum and colon, and serum of growing pigs. Twelve barrows(45 d of age, 12.08 ± 0.28 kg) fitted with a T-cannula at the terminal ileum, were randomly assigned to two groups and infused either saline without antibiotics(Control) or with antibiotics(Antibiotic) at the terminal ileum. After 25 d experiment, all pigs were euthanized for analyzing bacterial composition and immune status.Results: Ileum terminal antibiotic infusion(ITAI) altered dominant bacteria counts, with a decrease in Bifidobacterium, Clostridium cluster IV and Clostridium cluster IV in the colon(P < 0.05), and an increase in Escherichia coli in the jejunum(P < 0.05). ITAI decreased(P < 0.05) short-chain fatty acids concentrations in the colon. ITAI decreased interleukin-8(IL-8), IL-10 and secretory immunoglobulin A(sIgA) concentrations, and down-regulated IL-10, Mucin-1(MUC1), Mucin-2(MUC2) and zonula occludens-1(ZO-1) mRNA expression in the colonic mucosa(P < 0.05). In the jejunal mucosa, ITAI decreased interferon-γ(IFN-γ), tumor necrosis factor-α(TNF-α), s IgA and IgG levels together with down-regulation of IFN-γ, TNF-α, MUC2 and ZO-1 mRNA expression(P < 0.05). Furthermore, ITAI decreased IL-10, INF-γ, TNF-α, IgA and IgG concentrations in serum(P < 0.05). Correlation analysis revealed that the change in intestinal microbiota was correlated with alterations of Ig and cytokines.Conclusions: ITAI affected jejunal and colonic specific bacteria counts, and altered some immune markers levels in the jejunal and colonic mucosa and serum. These findings implicate the potential contribution of hindgut bacteria to immune response in the intestinal mucosa and serum of growing pigs.
基金Supported by Major Science and Technology Program of Hainan Province(ZDKJ2016017-01,ZDKJ2016017-03)
文摘[Objective] The paper was to investigate effects of pelleted total mixed ration on production performance and serum biochemical index of growing Hainan black goats.[Method] Twenty-four growing Hainan black goats with the same genetic backgrounds and similar initial weight of(10.05±0.049) kg were randomly assigned into two treatments, and supplied with Juncao + concentrate(control group), pelleted total mixed ration(experimental group), respectively. The trial lasted 50 d.[Result] The final weight, daily gain and feed intake of experimental group were significantly higher than those of control group(P<0.05), but the feed/gain ratio of experimental group was markedly lower than that of control group(P<0.05). Compared with the control group, the gross profit of experimental group significantly increased( P <0.05).[Conclusion] Pelleted total mixed ration led to better production performance of growing Hainan black goat.
基金supported by the Prevention and Control of Nutritional Metabolism and Toxic Diseases in Livestock and Poultry(2016YFD0501204)the 111 Project(B16044)
文摘Background: Determination of the endogenous loss of fat(ELF) is used to adjust for the estimation of true total tract digestibility(TTTD) of fat in diets and ingredients.Any factor which affected ELF may further affect the digestibility of fat,including sources and concentrations of fat and fiber in the diet.There are some reports of determining the ELF using regression methods based on different levels of fat intake,while reports on effects of dietary fiber content and different fiber-rich ingredients in pig diets on ELF are very limited.Therefore,the objective of this study was to determine the effects of dietary fiber content and different fiber-rich ingredients on endogenous losses of fat and fatty acids at the end of ileum and throughout the entire intestinal tract in growing pigs.Methods: In Exp.1,the effect of fiber content on endogenous loss of fat was determined using six growing pigs(Duroc × Landrace × Yorkshire;27.6 ± 2.4 kg),fitted with a T-cannula at the end of ileum.The experimental design was a 6 × 6 complete Latin square design with six periods of feeding and six diets.The six experimental fat-free diets were formulated to include graded levels of neutral detergent fiber(NDF)(0,40,80,120,160 and 200 g/kg) and soybean hull(SH) was the only fiber source,providing 0,75,150,225,300 and 375 g/kg,respectively.Chromic oxide was included at4 g/kg in all diets as an indigestible marker.In Exp.2,six crossbred growing barrows(27.6 ± 1.6 kg) were used and the experimental design was the same as for Exp.1.The six fat-free diets were formulated to include six common fiber-rich ingredients and the concentration of NDF was 100 g/kg.The six fiber-rich ingredients were defatted rice bran(DRB),sugar beet pulp(SBP),rice hull(RH),corn germ meal(CGM),SH and wheat bran(WB) and they were fed at represented250,270,145,250,170 and 280 g/kg in the diet,respectively.Results: In Exp.1,the endogenous loss of fatty acids profile did not change as dietary NDF increased in growing pigs.The endogenous losses of fat,C16:0,C18:0,C18:1,C18:2,total unsaturated fatty acids(UFA) and total saturated fatty acids(SFA) in growing pigs at the end of ileum and throughout the entire intestinal tract increased linearly as NDF content of diets increased.The endogenous losses of fat,as well as C16:0 and C18:0 throughout the entire intestinal tract also increased quadratically as NDF content of diets increased.The ELF increased from 0.71 to 3.14 g/kg of dry matter intake(DMI) and 0.56 to 8.21 g/kg DMI at the end of ileum and throughout the entire intestinal tract in growing pigs,respectively.The ELF occurred in the hindgut except for the growing pigs fed 0 and 4% NDF in their diets.The endogenous losses of C16:0 and UFA occurred primarily in the upper regions of the gut and the greatest endogenous losses of C18:0 occurred in the hindgut.The endogenous losses of fat,individual SFA and total SFA throughout the entire intestinal tract were much greater than that at the end of ileum.However,the endogenous losses of individual UFA and total UFA were less throughout the intestinal tract than at the end of ileum.In Exp.2,the endogenous losses of fat at the end of ileum were greater in growing pigs fed CGM or WB diets.The endogenous loss of fatty acids profile changed to a slight degree at the end of ileum that the endogenous loss of UFA(particularly C18:1 and C18:2) in growing pigs fed CGM or WB diets were greater(P < 0.01) than that for the other four diets.The greatest(P < 0.01) endogenous loss of SFA(particularly C18:0) was in growing pigs fed the RH diet.The endogenous losses of fat,C16:0,C18:0 and SFA over the entire intestinal tract were much greater in growing pigs fed CGM or WB diets,whereas the lowest values were in growing pigs fed DRB diet.The ELF at the end of ileum in growing pigs fed CGM or WB diets were 3.50 or 4.17 g/kg DMI,respectively,and the ELF over the entire intestinal tract was 7.23 or 7.38 g/kg DMI.The contribution in percentage of ELF in the upper gut was greater than that in the hindgut of growing pigs fed DRB and RH diets,while the ELF in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.On the whole,the endogenous losses of C18:1 and C18:2 throughout the entire intestinal tract in growing pigs fed the six fiber-rich ingredients diets were less than losses at the end of ileum,whereas the endogenous loss of fat,C16:0,C18:0 and SFA were greater throughout the intestinal tract than at the end of ileum.Conclusion: The profile of loss in endogenous fatty acids did not change as dietary NDF increased in growing pigs and the endogenous losses of fatty acids(C16:0,C18:0,C18:1 and C18:2) fat,UFA and SFA increased linearly as NDF content increased in the diets of pigs.The endogenous losses of fat or fatty acids at the end of ileum were greater in growing pigs fed RH,CGM or WB diets.The endogenous losses of fat,fatty acids(C16:0 and C18:0) and SFA were greater over the entire intestinal tract in pigs fed CGM or WB diet,while these values were the lowest in growing pigs fed the DRB diet.The contribution in percentage losses of fat in the upper gut were greater than in the hindgut of growing pigs fed DRB and RH diets,while the contribution of losses of fat in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.In addition,the endogenous loss of individual or total UFA was less over the entire intestinal tract of growing pigs fed fiber diets than that at the end of ileum,and the greatest endogenous losses of fat,individual or total SFA were over the entire intestinal tract.Therefore,differences in fiber content and the nature of fiber-rich ingredients in diets of pigs have different effects to the endogenous losses of fat or fatty acids.Considering the requirement of fat or fatty acids of pigs,careful attention must be paid that the endogenous losses of fat and fatty acids when fiber ingredients are used in diets of pigs.
基金supported in the framework of Grain Up by funds of the Federal Ministry of Food,AgricultureConsumer Protection(BMELV)based on a decision of the Parliament of the Federal Republic of Germany via the Federal Office for Agriculture Food and(BLE)under the innovation support program
文摘Background: Basal ileal endogenous amino acid(AA) losses(IAA_(end)) and standardized ileal digestibility(SID) values of cereal grains, such as barley, are apparently underestimated when determined according to the nitrogen(N)-free method. Regression analysis between the dietary apparent ileal digestible content(c AID) and total crude protein(CP) and AA can be considered as alternative approach to obtain more accurate values for IAA_(end)and SID of AA in cereal grains.Methods: Eight hulled barley genotypes were used, with barley being the only source of CP and AA in the assay diets. The diets contained 95 % as-fed of these eight barley genotypes each, ranging in CP content between 109.1 and 123.8 g/kg dry matter(DM). Nine ileally T-cannulated barrows, average body weight(BW) 30 ± 2 kg, were allotted to a row-column design comprising eight periods with 6 d each and nine pigs. On d 5 and the night of d 6 of every period, ileal digesta were collected for a total of 12 h. The IAA_(end) and the SID were determined by linear regression analysis between c AID and total dietary CP and AA.Results: There exist linear relationships between cA ID and total CP and AA(P < 0.001). The IAA_(end) of CP, Lys, Met, Thr and Trp amounted to 35.34, 1.08, 0.25, 1.02 and 0.38 g/kg DM intake(DMI), respectively, which are greater compared to average IAA_(end) determined previously under N-free feeding conditions. The SID of CP, Lys, Met, Thr and Trp was 90,79, 85, 79 and 86 %, respectively, and was greater when compared to tabulated values. Moreover, these SID values were greater than those reported in literature, based on correction of apparent ileal digestibility(AID) of CP and AA for their IAA_(end)values. Summarized, the results of the present regression analysis indicate greater IAA_(end)in barley-based diets compared to those obtained by N-free feeding.Conclusions: For low-protein feed ingredients like barley the regression method may be preferred over correction of AID values for their IAA_(end)determined under N-free feeding conditions, as intercepts and slopes of the linear regression equations between cA ID and total dietary CP and AA provide direct estimates of IAA_(end)and SID of CP and AA in the presence of the assay feed ingredient.
基金This work was mainly supported by National Natural Science Foundation of China(No.61370218)Public Welfare Technology and Industry Project of Zhejiang Provincial Science Technology Department(No.2016C31081,No.LGG18F020013)。
文摘Steganography technology has been widely used in data transmission with secret information.However,the existing steganography has the disadvantages of low hidden information capacity,poor visual effect of cover images,and is hard to guarantee security.To solve these problems,steganography using reversible texture synthesis based on seeded region growing and LSB is proposed.Secret information is embedded in the process of synthesizing texture image from the existing natural texture.Firstly,we refine the visual effect.Abnormality of synthetic texture cannot be fully prevented if no approach of controlling visual effect is applied in the process of generating synthetic texture.We use seeded region growing algorithm to ensure texture’s similar local appearance.Secondly,the size and capacity of image can be decreased by introducing the information segmentation,because the capacity of the secret information is proportional to the size of the synthetic texture.Thirdly,enhanced security is also a contribution in this research,because our method does not need to transmit parameters for secret information extraction.LSB is used to embed these parameters in the synthetic texture.
文摘Validated procedures play an important role to obtain accurate information about individual amino acid requirement data. The aim of the present study was to assess lysine (Lys) requirement of growing chicken both by classical supplementation technique and principles of diet dilution technique as applied with “Goettingen approach”. During the starter period (1 - 21 d), a growth study with male meat type chicken (Ross 308) was conducted making use of five graded dietary Lys-levels (3 repetition boxes with 3 birds/box). L-Lys×HCl was gradually added to a diet based on wheat, soybean protein concentrate, wheat gluten and fishmeal to yield 80%, 87.5%, 95%, 102.5% and 110% of the expected requirement level (13 g Lys/kg as fed). Diets were iso-energetic (12.8 MJME/kg) and iso-nitrogenous (21.65% crude protein). Birds were fed on free choice level also to assess the feed intake (FI) effects as important factor on traditional response criteria. Analyzed body composition at start and end of the growth study yielded N deposition (ND) data for further data assessment using exponential approximations depending on dietary Lys content or observed Lys intake. The results indicated significant differences (p < 0.05) in response on body weight gain (BWG) and observed dietary protein quality with unexpected consequences for the derived Lys requirement data. According to the independent variable (Lys in % of diet versus daily Lys intake) and aimed level of daily ND, the needed in-feed content of Lys varied between 1.24% and 1.46%. Application of the exponential modelling by “Goettingen approach” overcame these misleading conclusions by modelling the relationship between required Lys intake and observed response data (BWG, ND) taking also into account the expected real feed intake to formulate the needed in-feed concentration.
基金Supported by the Natural Science Foundation of Tianjin(No.15JCQNJC00200)
文摘Considering that growing hierarchical self-organizing map(GHSOM) ignores the influence of individual component in sample vector analysis, and its accurate rate in detecting unknown network attacks is relatively lower, an improved GHSOM method combined with mutual information is proposed. After theoretical analysis, experiments are conducted to illustrate the effectiveness of the proposed method by accurately clustering the input data. Based on different clusters, the complex relationship within the data can be revealed effectively.
文摘The grain growing dynamics including the growing process, the growing exponent and the growing activation energy is obtained for the MgO-CaO composite ceramics with the additions of Fe2O3, CeO2 and/or ZrO2 as fluxes by measuring the size of grains with the method of Straight Line Across. The results show that all of the additions, in which Fe2O3 is the strongest, have notable effects on the grain growing dynamics by reducing the growing activation energy and promoting the grain growing. The research gives a good reference for the additions of fluxes to the matrix of ceramic filter.
基金funded by National Key Research and Development Program of China(Grant number 2016YFD0501308)Agro-scientific Research in the Public Interest(Grant number 201403047)
文摘Background: The aim of this study was to investigate the intergeneric transfer of vancomycin resistance gene vanA between probiotic enterococci in the fermentation progress of soybean meal and in the digestive tract of growing pigs.One vanA genotype vancomycin resistant E.faecium strain,Efm4,and one chloramphenicol-resistant E.faecalis strain,Efs2,were isolated from twenty-nine probiotic basis feed material/additive samples.For in vitro conjugation,Efm4 and Efs2 were used as starter to ferment soybean meal.For in vivo conjugation,thirty growing pigs were randomly assigned to five groups(n = 6),treated with a basic diet,or supplemented with 10% fermented soybean meal,1% Efm4,5% Efs2 or a combination of 1% Efm4 + 5% Efs2 for 7 d,respectively.Fecal samples of pigs in each group were collected daily for the isolation and dynamic analysis of Efm4,Efs2 and transconjugants.The sequence types(STs) of Efm4,Efs2 and transconjugants were analyzed by multilocus sequence typing(MLST).The vanA harboring plasmid in Efm4 and transconjugants was analyzed by S1-pulsed field gel electrophoresis(PFGE)and further verified by multiple alignments.Results: The results showed that,in FSBM,transconjugants were detected 1 h after the fermentation,with a conjugation frequency of ~ 10^-3 transconjugants/recipient.Transconjugants proliferated with Efm4 and Efs2 in the first 8 h and maintained steadily for 10 d till the end of the experiment.Additionally,in vivo experiment showed that transcojugants were recovered in one of six pigs in both FSBM and Efm4 + Efs2 groups,with conjugation frequency of ~ 10^-5 and ~ 10^-4,respectively.MLST revealed the ST of Efm4,Efs2 and transconjugants was ST1014,ST69 and ST69,respectively.S1-PFGE confirmed the existence of the vanA-harboring,142,988-bp plasmid,which was also a multi-drug resistant plasmid containing Tn1546-like transposon.Conclusions: The findings revealed the potential safety hazard existing in the commercial probiotic enterococci in China,because the horizontal transfer from farm to fork could potentially pose a safety risk to the public.
