Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Ve...Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the sample size </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> small and the test </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> based on normal approximation. In this case, the only </span><span style="font-family:Verdana;">one</span><span style="font-family:Verdana;"> option that we have is to collect a large sample. Unfortunately, the large sample might not be possible. One example is a person suffering from a rare disease. The main purpose of this journal is to derive a closed formula for the exact distribution of the difference between two independent sample proportions, and use it to perform related inferences such as a confidence interval, regardless of the sample sizes and compare with the existing Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score. In this journal, we have derived a closed formula for the exact distribution of the difference between two independent sample proportions. This distribution doesn’t need any </span><span style="font-family:Verdana;">requirements,</span><span style="font-family:Verdana;"> and can be used to perform inferences such </span><span style="font-family:Verdana;">as:</span><span style="font-family:Verdana;"> a hypothesis test for two population proportions, regardless of the nature of the distribution and the sample sizes. We claim </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> exact distribution has the </span><span style="font-family:Verdana;">least</span><span style="font-family:Verdana;"> confidence width among Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score, so it is suitable for inferences of the difference between the population proportion regardless of sample size.展开更多
How are the winners determined in most of the events that make up the Olympic Games? Theyare,of course,the athletes who run or swim faster,jump higher,lift heavier,throw further.But how is their prowess measured? By t...How are the winners determined in most of the events that make up the Olympic Games? Theyare,of course,the athletes who run or swim faster,jump higher,lift heavier,throw further.But how is their prowess measured? By the SI (Système inter-national) International System of Units,which展开更多
Functional traits of trees are significantly associated with their adaptation strategies and productivity.However,the effects of species composition and mixing proportion on the functional traits of trees grown in mix...Functional traits of trees are significantly associated with their adaptation strategies and productivity.However,the effects of species composition and mixing proportion on the functional traits of trees grown in mixed plantations have not been studied extensively.In this study,planting experiments(duration about seven months)were used to study variations in functional traits and biomass allocation of C unninghamia lanceolata(Lamb.)Hook and Phoebe bournei(Hemsley)Yang seedlings in five different mixes(0C:4P,1C:3P,1C:1P,3C:1P,and 4C:0P).Total leaf area per seedling increased in each species as its respective proportion in the mixture decreased.However,the specific leaf area decreased for P.bournei under low percent composition,and the specific leaf area for C.lanceolata differed only marginally among the plantings.The net photosynthetic rates of the two species were higher in the mixed plantings than in their corresponding monocultures,whereas the transpiration rate,stomatal conductance,and instantaneous water use efficiency were not different among the plantings.The average root length and root surface area of C.lanceolata and P.bournei were higher in the mixed plantings than in their monocultures.Specifically,root surface area of C.lanceolate and both root length and surface area of P.bournei increased significantly in the 1C:3P and 2C:2P mixed plantings.Leaf,stem,root,and total dry mass per seedling for C.lanceolata decreased with its increasing percent composition in the mixed plantings,while these variables varied less for P.bournei.The plasticity of biomass allocation was relatively low for both species.Total biomass per planting was higher in the mixed plantings than in the monocultures.Our study indicates that species composition and mixing proportion can considerably affect the functional traits of C.lanceolata and P.bournei.The increase in productivity in the mixed plantings may be partially attributed to low rates of competition between the two species,and future studies should examine the different interspecies relationships.The results of this study can be used to improve plantation productivity and ultimately increase the sustainability of tree products and help to better understand the adaptation strategies of plant coexistence.展开更多
Eucalyptus camaldulensis Dehnh. and E. globulus Labill. are economically important species for wood and pulpwood materials. Representative heights for assessing whole-tree values of cell-type proportions(vessels, fibe...Eucalyptus camaldulensis Dehnh. and E. globulus Labill. are economically important species for wood and pulpwood materials. Representative heights for assessing whole-tree values of cell-type proportions(vessels, fibers, ray and axial parenchyma percentages) using increment cores were examined by analysis of within-tree variations. Pattern differences were evaluated between trees and species in both radial and axial directions by statistical data analysis(Moses test). In E. camaldulensis,within-tree variation of vessel percentage was generally higher in the upper and outer regions of the trunk. In contrast, E. globulus within-tree variation was unclear. In both species, although no clear pattern of fiber percentages was observed, within-tree variations of ray and axial parenchyma levels were higher in the lower and inner regions.Significant differences in patterns were observed in the axial variation between species for vessel percentages and in the radial variation between trees of E. camaldulensis for ray parenchyma percentages. The representative heights for assessing whole-tree cell-type proportions were 0.8 mabove the ground for E. camaldulensis and 2.8 m for E.globulus, regardless of differences in tree height and pattern of within-tree variation of cell-type proportions.展开更多
Let π=π1-π2 be the difference of two independent proportions related to two populations. We study the test H0:π≥0 against different alternatives, in the Bayesian context. The various Bayesian approaches use stand...Let π=π1-π2 be the difference of two independent proportions related to two populations. We study the test H0:π≥0 against different alternatives, in the Bayesian context. The various Bayesian approaches use standard beta distributions, and are simple to derive and compute. But the more general test H0:π≥η, with η>0, requires more advanced mathematical tools to carry out the computations. These tools, which include the density of the difference of two general beta variables, are presented in the article, with numerical examples for illustrations to facilitate comprehension of results.展开更多
Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present.Effects of the proportion of mill scale and coke breeze on the NO_(x) emissio...Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present.Effects of the proportion of mill scale and coke breeze on the NO_(x) emission,strength of sinter,and sinter indexes were studied by com-bustion and sinter pot tests.Results showed that the peak value of NO concentration,total of NO emission,and fuel-N conversion rate gradu-ally decreased as the proportions of the mill scale increased because NO was reduced to N_(2) by Fe_(3)O_(4),FeO,and Fe in the mill scale.The strength of sinter reached the highest value at 8.0wt%mill scale due to the formation of minerals with low melting point.The fuel-N conver-sion rate slightly fluctuated and total NO_(x) emission significantly decreased with the decreased proportions of coke breeze because CO forma-tion and content of N element in the sintered mixture decreased.However,the sinter strength also decreased due to the decrease in the amount of the melting minerals.Furthermore,results of the sinter pot tests indicated that NO_(x) emission decreased.The sinter indexes performed well when the proportions of mill scale and coke breeze were 8.0wt%and 3.70wt%respectively in the sintered mixture.展开更多
A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^(–1) au...A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^(–1) aureomycin,basal diet supplemented with different proportions of Bacillus licheniformis and Bacillus subtilis,which was 0:1.0×10~6,2.5×10~5:7.5×10~5,3.3×10~5:6.6×10~5,5.0×10~5:5.0×10~5,6.6×10~5:3.3×10~5,7.5×10~5:2.5×10~5 and 1.0×10~6:0,respectively.The duration of the experiment was 56 d.The results indicated that dietary supplementation of 6.6×10~5:3.3×10~5 of B.lichenifornis:B.subtilis improved final body weight,increased the average daily gain,and reduced feed/gain ratio(P<0.05).The numbers of total Lactobacillus and Bifidobacterium sp.in the caecum significantly increased,and the numbers of Escherichia coli and Salmonella sp.significantly declined compared to that of the control(P<0.05).Intestinal villous height and villous height to crypt depth ratio of the duodenum,jejunum,and ileum were significantly higher than that of the control,and intestinal crypt depth of the duodenum and ileum was significantly lower(P<0.05).The total antioxidant capacity,total superoxide dismutase,and glutathione peroxidase ability in plasma significantly improved,while the malondialdehyde concentration in plasma decreased(P<0.05).Compared to the control,plasma concentrations of ammonia,uric acid and urea nitrogen and the activity of xanthine oxidase were reduced(P<0.05).In conclusion,an inclusion of 6.6×10~5:3.3×10~5 of B.licheniformis:B.subtilis to the diet improved the growth performance,caecal microbiota,plasma biochemical profile,and significantly improved the small intestine morphology,while reducing the mortality rate.展开更多
Compositions,proportions,and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis.Crystalline rocks are us...Compositions,proportions,and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis.Crystalline rocks are usually composed of 4-6 minerals(phases),depending on their independent chemical components and the equilibrium temperature of crystallizations.In general,number of mineral phases can be determined by the "Phase Rule".According to the mass balance principle,bulk composition of coexisting two-feldspar could be evaluated from the bulk chemistry of a rock,provided that the compositions of the coexisting mafic mineral phases containing calcium,sodium,and potassium oxides are determined,e.g.,by microprobe analysis.The compositions,proportions,and temperature of two-feldspar in equilibrium can thus be simultaneously resolved numerically from bulk composition of the rock,by incorporating the activity/composition relations of the ternary feldspars with the mass balance constraints.Upon the numerical approximation method presented in this paper,better-quality,internally consistent data on feldspar group could usually be obtained,which would be expected more realistic and accurate in consideration of thermodynamic equilibria in the system of crystalline rocks,as well as bulk chemistry of a rock and the composing minerals.展开更多
In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds,in this study,the effect of different hormone proportions on differentiation and regen...In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds,in this study,the effect of different hormone proportions on differentiation and regeneration of shoot tip explants were investigated using Gisela No. 5 and Gisela No. 6 as experimental materials. The results showed that,different hormone proportions had extremely significant effects( P < 0. 01) on the differentiation rate of P. avium adventitious buds;the appropriate hormone proportions for Gisela No. 5 and Gisela No. 6 to induce dedifferentiation of adventitious buds were 6-BA 3. 0 mg/L + IBA 0. 5 mg/L + KT0. 1 mg/L and 6-BA 1. 0 mg/L + IBA 0. 5 mg/L + KT 0. 2 mg/L,respectively. In addition,different hormone proportions had extremely significant effects( P< 0. 01) on the regeneration coefficient and regeneration rate of P. avium adventitious buds; with the hormone proportion of 6-BA 1. 0 mg/L + IBA 1. 0 mg/L +KT 0. 3 mg/L,the number of regenerated adventitious buds reached the maximum for both varieties.展开更多
Due to the importance of the historical context of Dezful City,investigating historic buildings is necessary.But unfortunately,a large part of it is being destroyed.For this reason,it is essential to discover the guid...Due to the importance of the historical context of Dezful City,investigating historic buildings is necessary.But unfortunately,a large part of it is being destroyed.For this reason,it is essential to discover the guidelines and logic behind the architectural design of these buildings to help their reconstruction or restoration.Regrettably,there is no logical information about the components of this context and the reconstructions are usually done according to taste and based on architecture tested or personal preference.Therefore,it is necessary to find a logic behind these critical components that support the whole plan or parts of it in a particular style.The purpose of this research is to discover and find the logic behind the design of this building in the historical context of Dezful.Finding geometrical proportions can significantly help to reconstruct buildings better and more accurately.For this purpose,30 historical houses of Dezful were randomly selected,and their input information was drawn in 2D form in AutoCAD.Then,the length,width,and height proportions were measured,and the obtained ratios were compared with the golden proportions and dynamic rectangles.This paper studies entrance based on ratios of√2,√3,√4,√4,√1.25 andφ(the golden section).The results show that golden proportions and proportions derived from dynamic rectangles are present in the wording of all cases.Moreover,the range of ratios in the plan is from 1.34 to 2,and the content of changes in the section is from 1.22 to 2.The results can help architects,and particularly building owners,to reconstruct based on existing logic by discovering the proportions of the entrances of the houses.It is possible to administer a part of the damaged tissue and estimate its dimensions and sizes because the proportions’completeness can help revive half-destroyed historical buildings.展开更多
This study aims to reveal the impacts of three important uncertainty issues in landslide susceptibility prediction(LSP),namely the spatial resolution,proportion of model training and testing datasets and selection of ...This study aims to reveal the impacts of three important uncertainty issues in landslide susceptibility prediction(LSP),namely the spatial resolution,proportion of model training and testing datasets and selection of machine learning models.Taking Yanchang County of China as example,the landslide inventory and 12 important conditioning factors were acquired.The frequency ratios of each conditioning factor were calculated under five spatial resolutions(15,30,60,90 and 120 m).Landslide and non-landslide samples obtained under each spatial resolution were further divided into five proportions of training and testing datasets(9:1,8:2,7:3,6:4 and 5:5),and four typical machine learning models were applied for LSP modelling.The results demonstrated that different spatial resolution and training and testing dataset proportions induce basically similar influences on the modeling uncertainty.With a decrease in the spatial resolution from 15 m to 120 m and a change in the proportions of the training and testing datasets from 9:1 to 5:5,the modelling accuracy gradually decreased,while the mean values of predicted landslide susceptibility indexes increased and their standard deviations decreased.The sensitivities of the three uncertainty issues to LSP modeling were,in order,the spatial resolution,the choice of machine learning model and the proportions of training/testing datasets.展开更多
The emergence of antibiotic resistance in bacteria limits the availability of antibiotic choices for treatment and infection control,thereby representing a major threat to human health.The de novo mutation of bacteria...The emergence of antibiotic resistance in bacteria limits the availability of antibiotic choices for treatment and infection control,thereby representing a major threat to human health.The de novo mutation of bacterial genomes is an essential mechanism by which bacteria acquire antibiotic resistance.Previously,deletion mutations within bacterial immune systems,ranging from dozens to thousands of base pairs(bps)in length,have been associated with the spread of antibiotic resistance.Most current methods for evaluating genomic structural variations(SVs)have concentrated on detecting them,rather than estimating the proportions of populations that carry distinct SVs.A better understanding of the distribution of mutations and subpopulations dynamics in bacterial populations is needed to appreciate antibiotic resistance evolution and movement of resistance genes through populations.Here,we propose a statistical model to estimate the proportions of genomic deletions in a mixed population based on Expectation–Maximization(EM)algorithms and next-generation sequencing(NGS)data.The method integrates both insert size and split-read mapping information to iteratively update estimated distributions.The proposed method was evaluated with three simulations that demonstrated the production of accurate estimations.The proposed method was then applied to investigate the horizontal transfers of antibiotic resistance genes in concert with changes in the CRISPR-Cas system of E.faecalis.展开更多
文摘Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the sample size </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> small and the test </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> based on normal approximation. In this case, the only </span><span style="font-family:Verdana;">one</span><span style="font-family:Verdana;"> option that we have is to collect a large sample. Unfortunately, the large sample might not be possible. One example is a person suffering from a rare disease. The main purpose of this journal is to derive a closed formula for the exact distribution of the difference between two independent sample proportions, and use it to perform related inferences such as a confidence interval, regardless of the sample sizes and compare with the existing Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score. In this journal, we have derived a closed formula for the exact distribution of the difference between two independent sample proportions. This distribution doesn’t need any </span><span style="font-family:Verdana;">requirements,</span><span style="font-family:Verdana;"> and can be used to perform inferences such </span><span style="font-family:Verdana;">as:</span><span style="font-family:Verdana;"> a hypothesis test for two population proportions, regardless of the nature of the distribution and the sample sizes. We claim </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> exact distribution has the </span><span style="font-family:Verdana;">least</span><span style="font-family:Verdana;"> confidence width among Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score, so it is suitable for inferences of the difference between the population proportion regardless of sample size.
文摘How are the winners determined in most of the events that make up the Olympic Games? Theyare,of course,the athletes who run or swim faster,jump higher,lift heavier,throw further.But how is their prowess measured? By the SI (Système inter-national) International System of Units,which
基金supported by the Project of Public Welfare Technology Research in Zhejiang Province(LGN21C160010)the National Key Research and Development Program of China(No.2017YF C0505502)。
文摘Functional traits of trees are significantly associated with their adaptation strategies and productivity.However,the effects of species composition and mixing proportion on the functional traits of trees grown in mixed plantations have not been studied extensively.In this study,planting experiments(duration about seven months)were used to study variations in functional traits and biomass allocation of C unninghamia lanceolata(Lamb.)Hook and Phoebe bournei(Hemsley)Yang seedlings in five different mixes(0C:4P,1C:3P,1C:1P,3C:1P,and 4C:0P).Total leaf area per seedling increased in each species as its respective proportion in the mixture decreased.However,the specific leaf area decreased for P.bournei under low percent composition,and the specific leaf area for C.lanceolata differed only marginally among the plantings.The net photosynthetic rates of the two species were higher in the mixed plantings than in their corresponding monocultures,whereas the transpiration rate,stomatal conductance,and instantaneous water use efficiency were not different among the plantings.The average root length and root surface area of C.lanceolata and P.bournei were higher in the mixed plantings than in their monocultures.Specifically,root surface area of C.lanceolate and both root length and surface area of P.bournei increased significantly in the 1C:3P and 2C:2P mixed plantings.Leaf,stem,root,and total dry mass per seedling for C.lanceolata decreased with its increasing percent composition in the mixed plantings,while these variables varied less for P.bournei.The plasticity of biomass allocation was relatively low for both species.Total biomass per planting was higher in the mixed plantings than in the monocultures.Our study indicates that species composition and mixing proportion can considerably affect the functional traits of C.lanceolata and P.bournei.The increase in productivity in the mixed plantings may be partially attributed to low rates of competition between the two species,and future studies should examine the different interspecies relationships.The results of this study can be used to improve plantation productivity and ultimately increase the sustainability of tree products and help to better understand the adaptation strategies of plant coexistence.
基金partly supported by the CREST program of JST(Japan Science and Technology)and the Oji Paper Company,Japan。
文摘Eucalyptus camaldulensis Dehnh. and E. globulus Labill. are economically important species for wood and pulpwood materials. Representative heights for assessing whole-tree values of cell-type proportions(vessels, fibers, ray and axial parenchyma percentages) using increment cores were examined by analysis of within-tree variations. Pattern differences were evaluated between trees and species in both radial and axial directions by statistical data analysis(Moses test). In E. camaldulensis,within-tree variation of vessel percentage was generally higher in the upper and outer regions of the trunk. In contrast, E. globulus within-tree variation was unclear. In both species, although no clear pattern of fiber percentages was observed, within-tree variations of ray and axial parenchyma levels were higher in the lower and inner regions.Significant differences in patterns were observed in the axial variation between species for vessel percentages and in the radial variation between trees of E. camaldulensis for ray parenchyma percentages. The representative heights for assessing whole-tree cell-type proportions were 0.8 mabove the ground for E. camaldulensis and 2.8 m for E.globulus, regardless of differences in tree height and pattern of within-tree variation of cell-type proportions.
文摘Let π=π1-π2 be the difference of two independent proportions related to two populations. We study the test H0:π≥0 against different alternatives, in the Bayesian context. The various Bayesian approaches use standard beta distributions, and are simple to derive and compute. But the more general test H0:π≥η, with η>0, requires more advanced mathematical tools to carry out the computations. These tools, which include the density of the difference of two general beta variables, are presented in the article, with numerical examples for illustrations to facilitate comprehension of results.
基金This work was financially supported by the National Natural Science Foundation of China(No.51904127)the Natural Science Foundation of Jiangxi Province,China(No.20192BAB216018)+1 种基金the research and development Project(No.2018-YYB-05)collaborative innovation Project(No.2018-XTPH1-05)of Jiangxi Academy of Sciences,China.
文摘Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present.Effects of the proportion of mill scale and coke breeze on the NO_(x) emission,strength of sinter,and sinter indexes were studied by com-bustion and sinter pot tests.Results showed that the peak value of NO concentration,total of NO emission,and fuel-N conversion rate gradu-ally decreased as the proportions of the mill scale increased because NO was reduced to N_(2) by Fe_(3)O_(4),FeO,and Fe in the mill scale.The strength of sinter reached the highest value at 8.0wt%mill scale due to the formation of minerals with low melting point.The fuel-N conver-sion rate slightly fluctuated and total NO_(x) emission significantly decreased with the decreased proportions of coke breeze because CO forma-tion and content of N element in the sintered mixture decreased.However,the sinter strength also decreased due to the decrease in the amount of the melting minerals.Furthermore,results of the sinter pot tests indicated that NO_(x) emission decreased.The sinter indexes performed well when the proportions of mill scale and coke breeze were 8.0wt%and 3.70wt%respectively in the sintered mixture.
基金supported by the fund of Doctor Startup Project in Anhui Academy of Agricultural Sciences of Chinathe Project of Anhui Poultry Technology Committee, China (AHCYTX-10)
文摘A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^(–1) aureomycin,basal diet supplemented with different proportions of Bacillus licheniformis and Bacillus subtilis,which was 0:1.0×10~6,2.5×10~5:7.5×10~5,3.3×10~5:6.6×10~5,5.0×10~5:5.0×10~5,6.6×10~5:3.3×10~5,7.5×10~5:2.5×10~5 and 1.0×10~6:0,respectively.The duration of the experiment was 56 d.The results indicated that dietary supplementation of 6.6×10~5:3.3×10~5 of B.lichenifornis:B.subtilis improved final body weight,increased the average daily gain,and reduced feed/gain ratio(P<0.05).The numbers of total Lactobacillus and Bifidobacterium sp.in the caecum significantly increased,and the numbers of Escherichia coli and Salmonella sp.significantly declined compared to that of the control(P<0.05).Intestinal villous height and villous height to crypt depth ratio of the duodenum,jejunum,and ileum were significantly higher than that of the control,and intestinal crypt depth of the duodenum and ileum was significantly lower(P<0.05).The total antioxidant capacity,total superoxide dismutase,and glutathione peroxidase ability in plasma significantly improved,while the malondialdehyde concentration in plasma decreased(P<0.05).Compared to the control,plasma concentrations of ammonia,uric acid and urea nitrogen and the activity of xanthine oxidase were reduced(P<0.05).In conclusion,an inclusion of 6.6×10~5:3.3×10~5 of B.licheniformis:B.subtilis to the diet improved the growth performance,caecal microbiota,plasma biochemical profile,and significantly improved the small intestine morphology,while reducing the mortality rate.
基金granted by the National Eleventh Five-year Supporting Plan for Science and Technology (2006BAD10B04)China Geological Survey Project (12120113087700)
文摘Compositions,proportions,and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis.Crystalline rocks are usually composed of 4-6 minerals(phases),depending on their independent chemical components and the equilibrium temperature of crystallizations.In general,number of mineral phases can be determined by the "Phase Rule".According to the mass balance principle,bulk composition of coexisting two-feldspar could be evaluated from the bulk chemistry of a rock,provided that the compositions of the coexisting mafic mineral phases containing calcium,sodium,and potassium oxides are determined,e.g.,by microprobe analysis.The compositions,proportions,and temperature of two-feldspar in equilibrium can thus be simultaneously resolved numerically from bulk composition of the rock,by incorporating the activity/composition relations of the ternary feldspars with the mass balance constraints.Upon the numerical approximation method presented in this paper,better-quality,internally consistent data on feldspar group could usually be obtained,which would be expected more realistic and accurate in consideration of thermodynamic equilibria in the system of crystalline rocks,as well as bulk chemistry of a rock and the composing minerals.
基金Supported by Special Fund for Key Laboratory of Shaanxi Provincial Scienceand Technology Department(2011HBSZS003)
文摘In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds,in this study,the effect of different hormone proportions on differentiation and regeneration of shoot tip explants were investigated using Gisela No. 5 and Gisela No. 6 as experimental materials. The results showed that,different hormone proportions had extremely significant effects( P < 0. 01) on the differentiation rate of P. avium adventitious buds;the appropriate hormone proportions for Gisela No. 5 and Gisela No. 6 to induce dedifferentiation of adventitious buds were 6-BA 3. 0 mg/L + IBA 0. 5 mg/L + KT0. 1 mg/L and 6-BA 1. 0 mg/L + IBA 0. 5 mg/L + KT 0. 2 mg/L,respectively. In addition,different hormone proportions had extremely significant effects( P< 0. 01) on the regeneration coefficient and regeneration rate of P. avium adventitious buds; with the hormone proportion of 6-BA 1. 0 mg/L + IBA 1. 0 mg/L +KT 0. 3 mg/L,the number of regenerated adventitious buds reached the maximum for both varieties.
文摘Due to the importance of the historical context of Dezful City,investigating historic buildings is necessary.But unfortunately,a large part of it is being destroyed.For this reason,it is essential to discover the guidelines and logic behind the architectural design of these buildings to help their reconstruction or restoration.Regrettably,there is no logical information about the components of this context and the reconstructions are usually done according to taste and based on architecture tested or personal preference.Therefore,it is necessary to find a logic behind these critical components that support the whole plan or parts of it in a particular style.The purpose of this research is to discover and find the logic behind the design of this building in the historical context of Dezful.Finding geometrical proportions can significantly help to reconstruct buildings better and more accurately.For this purpose,30 historical houses of Dezful were randomly selected,and their input information was drawn in 2D form in AutoCAD.Then,the length,width,and height proportions were measured,and the obtained ratios were compared with the golden proportions and dynamic rectangles.This paper studies entrance based on ratios of√2,√3,√4,√4,√1.25 andφ(the golden section).The results show that golden proportions and proportions derived from dynamic rectangles are present in the wording of all cases.Moreover,the range of ratios in the plan is from 1.34 to 2,and the content of changes in the section is from 1.22 to 2.The results can help architects,and particularly building owners,to reconstruct based on existing logic by discovering the proportions of the entrances of the houses.It is possible to administer a part of the damaged tissue and estimate its dimensions and sizes because the proportions’completeness can help revive half-destroyed historical buildings.
基金This research is funded by the National Natural Science Foundation of China(41807285,41762020,51879127 and 51769014E)Natural Science Foundation of Hebei Province(D2022202005).
文摘This study aims to reveal the impacts of three important uncertainty issues in landslide susceptibility prediction(LSP),namely the spatial resolution,proportion of model training and testing datasets and selection of machine learning models.Taking Yanchang County of China as example,the landslide inventory and 12 important conditioning factors were acquired.The frequency ratios of each conditioning factor were calculated under five spatial resolutions(15,30,60,90 and 120 m).Landslide and non-landslide samples obtained under each spatial resolution were further divided into five proportions of training and testing datasets(9:1,8:2,7:3,6:4 and 5:5),and four typical machine learning models were applied for LSP modelling.The results demonstrated that different spatial resolution and training and testing dataset proportions induce basically similar influences on the modeling uncertainty.With a decrease in the spatial resolution from 15 m to 120 m and a change in the proportions of the training and testing datasets from 9:1 to 5:5,the modelling accuracy gradually decreased,while the mean values of predicted landslide susceptibility indexes increased and their standard deviations decreased.The sensitivities of the three uncertainty issues to LSP modeling were,in order,the spatial resolution,the choice of machine learning model and the proportions of training/testing datasets.
基金This work was supported by the National Institutes of Health[Grant R15GM131390 to X.W.,Grant R01CA245294 to M.Z.,and Grant R01AI116610 to K.P.]。
文摘The emergence of antibiotic resistance in bacteria limits the availability of antibiotic choices for treatment and infection control,thereby representing a major threat to human health.The de novo mutation of bacterial genomes is an essential mechanism by which bacteria acquire antibiotic resistance.Previously,deletion mutations within bacterial immune systems,ranging from dozens to thousands of base pairs(bps)in length,have been associated with the spread of antibiotic resistance.Most current methods for evaluating genomic structural variations(SVs)have concentrated on detecting them,rather than estimating the proportions of populations that carry distinct SVs.A better understanding of the distribution of mutations and subpopulations dynamics in bacterial populations is needed to appreciate antibiotic resistance evolution and movement of resistance genes through populations.Here,we propose a statistical model to estimate the proportions of genomic deletions in a mixed population based on Expectation–Maximization(EM)algorithms and next-generation sequencing(NGS)data.The method integrates both insert size and split-read mapping information to iteratively update estimated distributions.The proposed method was evaluated with three simulations that demonstrated the production of accurate estimations.The proposed method was then applied to investigate the horizontal transfers of antibiotic resistance genes in concert with changes in the CRISPR-Cas system of E.faecalis.
