Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient...Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.展开更多
Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseas...Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseases is the aberrant cerebral accumulation of pathological protein aggregates,affecting selectively vulnerable circuits in a disease-specific pattern.Earlier studies have established a relationship between abnormal aggregation and neuronal dysfunction or loss,suggesting multifactorial pathogenesis mechanisms in these neurodegenerative disorders.展开更多
BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,...BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,and other examinations show certain characteristics of the disease,but lack accuracy.Although capsule endoscopy and enteroscopy make up for this deficiency,the diagnosis also still re-quires pathology.CASE SUMMARY A male patient was admitted to the hospital due to abdominal distension and abdominal pain,but a specific diagnosis by computed tomography examination was not obtained.Partial resection of the small intestine was performed by robotic surgery,and postoperative pathological biopsy confirmed the diagnosis of hemo-lymphangioma.No recurrence in the follow-up examination was observed.CONCLUSION Robotic surgery is an effective way to treat hemolymphangioma through minima-lly invasive techniques under the concept of rapid rehabilitation.展开更多
[Objectives]This study aimed to investigate the incidence and risk factors associated with SSD in patients following cardiac surgery.[Methods]A total of 378 patients who underwent cardiac surgery in Taihe Hospital wer...[Objectives]This study aimed to investigate the incidence and risk factors associated with SSD in patients following cardiac surgery.[Methods]A total of 378 patients who underwent cardiac surgery in Taihe Hospital were recruited and screened.Diagnosis of delirium was made using evaluation methods and DSM-5 criteria.SSD was defined as the presence of one or more core features of delirium without meeting the full diagnostic criteria.Statistical analysis included independent samples t-test for group comparisons and binary logistic regression analysis to identify independent risk factors for SSD after cardiac surgery.[Results]Among the 378 subjects,112(29.63%)had SSD,28(7.41%)had delirium,and the remaining 238 patients(62.96%)did not present with delirium.Univariate analysis revealed that age,APACHE II score,duration of aortic clamping,length of ICU stay,duration of sedation use,and daily sleep time were significant risk factors for the occurrence of SSD(P<0.05).Logistic regression analysis identified age>70 years old,APACHE II score>20 points,length of ICU stay>5 d,and duration of sedation use>24 h as independent risk factors for SSD after cardiac surgery(P<0.05).A functional model was fitted based on the analysis results of the binary logistic regression model,yielding the equation logit P=1.472X_(1)+2.213X_(2)+3.028X_(3)+1.306X_(4).[Conclusions]Comprehensive clinical assessment is crucial for patients undergoing cardiac surgery,and appropriate preventive measures should be taken for patients with identified risk factors.Close monitoring of the patient s consciousness should be implemented postoperatively,and timely interventions should be conducted.Further research should focus on model validation and optimization.展开更多
Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This stu...Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This study was conducted to investigate the effect of maternal basel diet(control)supplemented with an organic Se,2-hydroxy-4-methylselenobutanoic acid(HMSeBA),or inorganic sodium selenite(Na_(2)SeO_(3))during gestation on the antioxidant status and development of muscle in newborn and weaned piglets.Newborn piglets before colostrum intake and weaned piglets were selected for longissimus dorsi(LD)muscle collection and analysis.Results:The results showed that maternal HMSeBA supplementation increased the muscle area and content of Se in the LD muscle of newborn piglets,improved gene expression of selenoproteins,and decreased oxidative status in the LD muscle of both newborn and weaned piglets compared with the control.The expression of muscle development-related genes of newborn piglets in the HMSeBA group was lower than in the control group,whereas the expression of MRF4 in weaned piglets was higher in the HMSeBA group than in the control and Na_(2)SeO_(3)groups.In addition,HMSeBA supplementation decreased the mRNA expressions of myosin heavy chains(MyHC)IIx and MyHC IIb and the percentage of MyHC IIb;increased the expression of PGC-1αin the LD muscle of newborn piglets;increased the gene expression of MyHC IIa;and decreased the protein expression of slow MyHC and the activity of malate dehydrogenase in the LD muscle of weaned piglets compared with the control group.Conclusions:Maternal HMSeBA supplementation during gestation can improve the antioxidative capacity of the muscle of their offspring and promote the maturity of muscle fibres in weaned offspring.展开更多
BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the ...BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice.Ferroptosis,a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation,is an important mechanism by which CAP induces cell death.Therefore,ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after transplantation.AIM To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP.METHODS A rat LT model of acute rejection was established,and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT.In vitro,primary CD3+T cells were sorted from rat spleens and human peripheral blood,and co-cultured with or without 5-fluorouracil(5-FU)(active agent of CAP).The levels of ferroptosis-related proteins,ferrous ion concentration,and oxidative stress-related indicators were observed.The changes in mitochondrial structure were observed using electron microscopy.RESULTS With no significant myelotoxicity,metronomic CAP alleviated graft injury(Banff score 9 vs 7.333,P<0.001),prolonged the survival time of the recipient rats(11.5 d vs 16 d,P<0.01),and reduced the infiltration rate of CD3+T cells in peripheral blood(6.859 vs 3.735,P<0.001),liver graft(7.459 vs 3.432,P<0.001),and spleen(26.92 vs 12.9,P<0.001),thereby inhibiting acute rejection after LT.In vitro,5-FU,an end product of CAP metabolism,induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4,which caused the accumulation of ferrous ions.It also inhibited nuclear erythroid 2 p45-related factor 2,heme oxygenase-1,and glutathione peroxidase 4,eventually leading to oxidative damage and ferroptosis of T cells.CONCLUSION Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+T cell ferroptosis,which makes it an effective immunosuppressive agent after LT.展开更多
The amount of 3D data stored and transmitted in the Internet of Medical Things(IoMT)is increasing,making protecting these medical data increasingly prominent.However,there are relatively few researches on 3D data wate...The amount of 3D data stored and transmitted in the Internet of Medical Things(IoMT)is increasing,making protecting these medical data increasingly prominent.However,there are relatively few researches on 3D data watermarking.Moreover,due to the particularity of medical data,strict data quality should be considered while protecting data security.To solve the problem,in the field of medical volume data,we proposed a robust watermarking algorithm based on Polar Cosine Transform and 3D-Discrete Cosine Transform(PCT and 3D-DCT).Each slice of the volume data was transformed by PCT to obtain feature row vector,and then the reshaped three-dimensional feature matrix was transformed by 3D-DCT.Based on the contour information of the volume data and the detail information of the inner slice,the visual feature vector was obtained by applying the per-ceptual hash.In addition,the watermark was encrypted by a multi-sensitive initial value Sine and Piecewise linear chaotic Mapping(SPM)system,and embedded as a zero watermark.The key was stored in a third party.Under the same experimental conditions,when the volume data is rotated by 80 degrees,cut 25%along the Z axis,and the JPEG compression quality is 1%,the Normalized Correlation Coefficient(NC)of the extracted watermark is 0.80,0.89,and 1.00 respectively,which are significantly higher than the comparison algorithm.展开更多
随着柴油车数量的增加,NO_x污染的控制成为了当今社会的一个重要议题,NO_x可以导致酸雨,光化学烟雾以及慢性健康问题.目前,具有八元环孔口的含铜CHA型分子筛(包括Cu-SSZ-13和Cu-SPAO-34)具有优异的高温水热稳定性及宽温度范围内的活性和...随着柴油车数量的增加,NO_x污染的控制成为了当今社会的一个重要议题,NO_x可以导致酸雨,光化学烟雾以及慢性健康问题.目前,具有八元环孔口的含铜CHA型分子筛(包括Cu-SSZ-13和Cu-SPAO-34)具有优异的高温水热稳定性及宽温度范围内的活性和N_2选择性,是最具有吸引力的氨选择催化还原催化剂,而且在欧洲和美国已经得到了应用.SAPO-34分子筛的一个重要缺陷就是在100 ℃以下,对水较为敏感,这主要是由于Si–O–Al键的水解造成的.研究表明,在室温下接触水蒸气后,SAPO-34的结晶度和比表面积只能部分恢复,而如果长达数月甚至更长时间的接触后,分子筛将会遭受骨架坍塌等不可逆的破坏,到目前为止,Cu-SAPO-34的低温水热稳定性相关问题并未得到清楚的阐述.本文系统研究了不同铜含量和硅含量的Cu-SAPO-34催化剂的低温水热稳定性.结果显示,低温水热处理后,所有催化剂的NH_3氧化活性和NH_3-SCR活性(主要是低温活性)都有所下降.29Si MAS NMR结果表明,在低温水热处理过程中,骨架结构的破坏在所难免,但催化剂上铜含量的增加有助于Cu-SAPO-34的骨架结构和酸性的更好保持.EPR结果表明,当催化剂上铜含量较低时,孤立Cu^(2+)的稳定性和SAPO分子筛骨架的稳定性呈现正相关的关系.具有较高铜含量(如3.67 wt%)的样品,尽管其骨架结构和酸性在低温水热处理过程中可以得到较好的保持,但活性Cu^(2+)的量仍会有明显的下降.由于部分样品在低温水处理后,NH_3氧化反应活性下降,我们推测CuO颗粒发生了聚结,从而抑制了催化剂的NH_3氧化反应活性,N_2O化学吸附实验也证实了该结论.在所有催化剂中,具有中等铜含量(1.37%)的高硅Cu-SAPO-34样品在低温水处理过程中的Cu^(2+)量和酸性质均得到了较好的保持,所以其水处理后的NH_3-SCR活性衰减最小.展开更多
Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimizati...Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring.展开更多
The development of kesterite photovoltaic solar cells has been hindered by large open-circuit voltage(V_(oc))deficit.Recently,Snzn deep point defect and associative defect cluster have been recognized as the main culp...The development of kesterite photovoltaic solar cells has been hindered by large open-circuit voltage(V_(oc))deficit.Recently,Snzn deep point defect and associative defect cluster have been recognized as the main culprit for the Voc losses.Therefore,manipulating the deep-level donor of Snzn antisite defects is crucial for breaking through the bottleneck of present Cu_(2) ZnSn(S,Se)_(4)(CZTSSe)photovoltaic technology.In this study,the Snzn deep traps in CZTSSe absorber layer are suppressed by incorporation of Ge.The energy levels and concentration of Snzn defects measured by deep-level transient spectroscopy(DLTS)decrease significantly.In addition,the grain growth of CZTSSe films is also promoted due to Ge implantation,yielding the high quality absorber layer.Consequently,the efficiency of CZTSSe solar cells increases from 9.15%to 11.48%,largely attributed to the 41 mV Voc increment.展开更多
Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field sur...Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field surveys to estimate the species'population size were almost totally conducted in coastal areas,but tracking studies showed that some individuals now winter inland.To ensure its long-term survival,we need a more comprehensive assessment of the current distribution and abundance of the species.Methods:We combined the most recent count data and satellite tracking information to update existing informa-tion about the population abundance and distribution of the Black-faced Spoonbill at all stages of its annual life cycle,and how these have changed during 2004-2020.Results:Black-faced Spoonbills mainly breed on the west coast of the Korean peninsula,while immature birds show a wider summer distribution throughout Yellow Sea coastal areas,when a few remain on wintering sites in the south.Combined tracking results and mid-winter counts confirmed known wintering sites on the east and south coasts of China,but showed that the species also winters on wetlands in the Yangtze River floodplain and in Southeast Asia.During 2004-2020,counts of wintering birds in coastal habitats increased from 1198 to 4864,with numbers wintering on the island of Taiwan contributing most to the overall increase.Latest counts found 5222 in 2021.We also identify key wintering and stopover sites as well as their current conservation status.Conclusions:This study revised the known summering and wintering ranges of the Black-faced Spoonbill and assessed the conservation status of key sites based on a combination of field survey and satellite tracking data.We recommend prioritisation of further field research to identify and survey inland wintering areas in the Yangtze River floodplain and summering areas of immature birds.More tracking of adult individuals and birds during spring migration is necessary to fill these information gaps.We also suggest establishing a Black-faced Spoonbill monitoring platform to store,share and show real-time distribution range and population abundance data.展开更多
Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Her...Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively.展开更多
Background:Evidence suggests that wintering waterbirds have become conspicuously more concentrated at two largest lakes of the Yangtze River Floodplain,East Dong Ting Lake(Hunan Province,29°20′N,113°E)and P...Background:Evidence suggests that wintering waterbirds have become conspicuously more concentrated at two largest lakes of the Yangtze River Floodplain,East Dong Ting Lake(Hunan Province,29°20′N,113°E)and Poyang Lake(Jiangxi Province,29°N,116°20′E),relative to other lakes,despite the establishment of reserves elsewhere.While this relationship is likely due to greater extent of undisturbed habitats in larger lakes,we understand little of the drivers affecting individual behaviours behind this tendency.Methods:We tracked wintering movements of three duck species(Eurasian Wigeon Mareca penelope,Falcated Duck M.falcata and Northern Pintail Anas acuta)using GPS transmitters,examining differences between the two largest lakes and other smaller lakes in ducks’habitat use,duration of stay at each lake and the daily distances moved by the tagged birds while at these sites.Results:The Eurasian Wigeon and Falcated Duck stayed five times longer and almost exclusively used natural habitat types at the two large lakes(91‒95%of positions)compared to length of stay time at smaller lakes,where they spent 28‒33 days on average(excluding the capture site)and exploited many more different habitats(including c.50%outside lakes).Conclusions:Our study is the first to show that shorter length of stay and more varied habitat use by ducks at small lakes may contribute to explaining the apparent regional concentration of numbers present of these and other species at the largest lakes in recent years.This compares with their declining abundance at smaller lakes,where habitat loss and degradation has been more manifest than on the larger lakes.展开更多
Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian sub-continent.Of the two ...Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian sub-continent.Of the two recognized discrete flyways of the Bar-headed Goose,the Eastern Tibetan Flyway(ETF)is the larger,comprising at least six migration routes.However,we remain ignorant about their migratory connectivity,habitat use and effectiveness of site-safeguard mechanisms set in place for the species.Methods:We tracked 30 ETF Bar-headed Geese from Chinese and Mongolian breeding areas to their wintering grounds using GPS/GSM transmitters,to determine their migration routes and stopover staging patterns within the QTP,overlaying these upon GIS layers of protected area status and habitat type,to model their habitat selection.Results:In total,14 tagged Bar-headed Geese provided information on their entire autumn migration and 4 geese on their entire spring migration.Qinghai Lake marked birds overwintered in the QTP(n=2),geese tagged in Mongolia wintered either in the QTP(n=3)or in India/Bangladesh(n=9),representing three of the migration routes within the ETF.In total,tagged birds staged at 79 different stopover sites within QTP in autumn and 23 in spring,of which 65%(autumn)and 59%(spring)of all fixes fell within the boundaries of either National Nature Reserves(NNRs)or Important Birds Areas(IBAs)in the QTP.Bar-headed Geese predominantly occurred on four land-cover types:grassland(mostly by day),water bodies(at night),wetlands and bare substrates(salt flats,dry lake/river substrates and plough)with little change in proportion.Generalized linear mixed models comparing presence with pseudo-absence data suggested geese strongly selected for wetlands as staging habitat,avoiding bare substrates in spring.Conclusions:Based on our limited observations of these tagged geese,this study is the first to show that the current designated National Nature Reserves in place in the staging areas within the QTP appear adequate to protect this increasing population.In addition,Hala Lake in Qinghai Province and adjacent areas used as initial QTP staging during autumn migration(currently outside of designated as NNRs/IBAs)are recommended for protection,based on their use by tagged birds from this study.Habitat modelling confirmed the importance of natural wetlands as feeding areas and safe areas of open water as roosting places.展开更多
Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly ...Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly field surveys. The Swan Goose(Anser cygnoides), a vulnerable Anatidae species, winters almost exclusively in China's Yangtze River floodplain, but wintering numbers have been steadily decreasing. To better safeguard this unique species, modern modeling approaches can be used to quantify and predict its suitable wintering habitat. Specifically, a potential wintering distribution map of this species is critically important.Methods: This study used the maximum entropy approach to model a distribution map of this species. In total, data from 97 up-to-date sites were extracted from 1263 survey sites(excluding duplicate data). After eliminating spatial autocorrelation, 11 environmental variables, including factors related to climate, land structure, vegetation, and anthropogenic activities, were used for model prediction.Results: The prediction distribution map shows that the population has concentrated mainly in the boundary area of Anhui, Hubei, and Jiangxi provinces, especially along the Yangtze River. Modeling results suggest that areas within the middle and lower Yangtze River floodplain, such as those in Hunan and Hubei provinces and the eastern coastal area of Zhejiang Province, demonstrate a potential level of "medium" suitability for this species to winter.Conclusions: Results from this study provide fundamental information for the restoration and management of the Swan Goose. Our "visualized" potential distribution map can assist in planning optimal conservation strategies, and consequently may help to increase the number of wintering populations in China.展开更多
Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining a...Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. For waterfowl foraging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals foraging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) foraging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. Finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at different sediment layers (1–10, 11–20 and 21–30 cm below the surface). Results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese foraged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the first to quantify foraging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on foraging selection of belowground foragers.展开更多
The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal n...The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal neurons after injury, but the mechanism by which it affects excitatory synaptic transmission remains poorly understood. Our results showed that diazepam treatment significantly increased the slope of input-output curves in rat neurons after fluid percussion injury. Diazepam significantly decreased the numbers of spikes evoked by super stimuli in the presence of 15 μmol/L bicuculline, indicating the existence of inhibitory pathways in the injured rat hippocampus. Diazepam effectively increased the paired-pulse facilitation ratio in the hippocampal CA1 region following fluid percussion injury, reduced miniature excitatory postsynaptic potentials, decreased action-potential-dependent glutamine release, and reversed spontaneous glutamine release. These data suggest that diazepam could decrease the fluid percussion injury-induced enhancement of excitatory synaptic transmission in the rat hippocampal CA1 area.展开更多
Some evidence suggests that multiwalled carbon nanotubes can promote neuronal differentiation and growth. The present study investigated the effect of functional multiwalled carbon nanotubes (MWCNTs) on functional rec...Some evidence suggests that multiwalled carbon nanotubes can promote neuronal differentiation and growth. The present study investigated the effect of functional multiwalled carbon nanotubes (MWCNTs) on functional recovery of injured sciatic nerves in mice. The results revealed that MWCNTs accelerated the recovery of functional index scores of injured sciatic nerves in mice. Moreover, the medullary sheath was significantly thicker in the injured sciatic nerve following MWCNTs administration. These effects were dose-dependent.展开更多
基金Supported by the Marine S&T Fund of Shandong Province for Qingdao Marine Science and Technology Center(No.2022QNLM030004-1)the National Natural Science Foundation of China(Nos.42276153,42030407)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42020401)the Key Research Program of Frontier Sciences,CAS(No.ZDBS-LY-DQC032)the National Key R&D Program of China(No.2022YFC2804003)。
文摘Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.
基金RN received funding from Swiss Centre for Applied Human ToxicologyHelmut Hortun Stiftung。
文摘Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseases is the aberrant cerebral accumulation of pathological protein aggregates,affecting selectively vulnerable circuits in a disease-specific pattern.Earlier studies have established a relationship between abnormal aggregation and neuronal dysfunction or loss,suggesting multifactorial pathogenesis mechanisms in these neurodegenerative disorders.
基金Supported by Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-015A and No.TJYXZDXK-058B.
文摘BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,and other examinations show certain characteristics of the disease,but lack accuracy.Although capsule endoscopy and enteroscopy make up for this deficiency,the diagnosis also still re-quires pathology.CASE SUMMARY A male patient was admitted to the hospital due to abdominal distension and abdominal pain,but a specific diagnosis by computed tomography examination was not obtained.Partial resection of the small intestine was performed by robotic surgery,and postoperative pathological biopsy confirmed the diagnosis of hemo-lymphangioma.No recurrence in the follow-up examination was observed.CONCLUSION Robotic surgery is an effective way to treat hemolymphangioma through minima-lly invasive techniques under the concept of rapid rehabilitation.
基金Supported by Philosophy and Social Science Research Project of Hubei Education Department in 2022(22D092)Guiding Scientific Research Project of Shiyan Science and Technology Bureau in 2022(22Y34).
文摘[Objectives]This study aimed to investigate the incidence and risk factors associated with SSD in patients following cardiac surgery.[Methods]A total of 378 patients who underwent cardiac surgery in Taihe Hospital were recruited and screened.Diagnosis of delirium was made using evaluation methods and DSM-5 criteria.SSD was defined as the presence of one or more core features of delirium without meeting the full diagnostic criteria.Statistical analysis included independent samples t-test for group comparisons and binary logistic regression analysis to identify independent risk factors for SSD after cardiac surgery.[Results]Among the 378 subjects,112(29.63%)had SSD,28(7.41%)had delirium,and the remaining 238 patients(62.96%)did not present with delirium.Univariate analysis revealed that age,APACHE II score,duration of aortic clamping,length of ICU stay,duration of sedation use,and daily sleep time were significant risk factors for the occurrence of SSD(P<0.05).Logistic regression analysis identified age>70 years old,APACHE II score>20 points,length of ICU stay>5 d,and duration of sedation use>24 h as independent risk factors for SSD after cardiac surgery(P<0.05).A functional model was fitted based on the analysis results of the binary logistic regression model,yielding the equation logit P=1.472X_(1)+2.213X_(2)+3.028X_(3)+1.306X_(4).[Conclusions]Comprehensive clinical assessment is crucial for patients undergoing cardiac surgery,and appropriate preventive measures should be taken for patients with identified risk factors.Close monitoring of the patient s consciousness should be implemented postoperatively,and timely interventions should be conducted.Further research should focus on model validation and optimization.
基金supported by Fok Ying Tung Education Foundation(171019)Natural Science Foundation of Sichuan Province(2021NZZJ0016)the 111 project(D17015).
文摘Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This study was conducted to investigate the effect of maternal basel diet(control)supplemented with an organic Se,2-hydroxy-4-methylselenobutanoic acid(HMSeBA),or inorganic sodium selenite(Na_(2)SeO_(3))during gestation on the antioxidant status and development of muscle in newborn and weaned piglets.Newborn piglets before colostrum intake and weaned piglets were selected for longissimus dorsi(LD)muscle collection and analysis.Results:The results showed that maternal HMSeBA supplementation increased the muscle area and content of Se in the LD muscle of newborn piglets,improved gene expression of selenoproteins,and decreased oxidative status in the LD muscle of both newborn and weaned piglets compared with the control.The expression of muscle development-related genes of newborn piglets in the HMSeBA group was lower than in the control group,whereas the expression of MRF4 in weaned piglets was higher in the HMSeBA group than in the control and Na_(2)SeO_(3)groups.In addition,HMSeBA supplementation decreased the mRNA expressions of myosin heavy chains(MyHC)IIx and MyHC IIb and the percentage of MyHC IIb;increased the expression of PGC-1αin the LD muscle of newborn piglets;increased the gene expression of MyHC IIa;and decreased the protein expression of slow MyHC and the activity of malate dehydrogenase in the LD muscle of weaned piglets compared with the control group.Conclusions:Maternal HMSeBA supplementation during gestation can improve the antioxidative capacity of the muscle of their offspring and promote the maturity of muscle fibres in weaned offspring.
基金Supported by National Key Research and Development Program of China,No.2020YFA0710802The Youth Science Fund of the Nature Science Foundation of Tianjin,No.20JCQNJC01370+1 种基金The Key Projects of Tianjin Science and Technology Project,No.21JCZDJC00160The Science Foundation of Tianjin Health Commission,No.ZC20065 and No.ZC20089.
文摘BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice.Ferroptosis,a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation,is an important mechanism by which CAP induces cell death.Therefore,ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after transplantation.AIM To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP.METHODS A rat LT model of acute rejection was established,and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT.In vitro,primary CD3+T cells were sorted from rat spleens and human peripheral blood,and co-cultured with or without 5-fluorouracil(5-FU)(active agent of CAP).The levels of ferroptosis-related proteins,ferrous ion concentration,and oxidative stress-related indicators were observed.The changes in mitochondrial structure were observed using electron microscopy.RESULTS With no significant myelotoxicity,metronomic CAP alleviated graft injury(Banff score 9 vs 7.333,P<0.001),prolonged the survival time of the recipient rats(11.5 d vs 16 d,P<0.01),and reduced the infiltration rate of CD3+T cells in peripheral blood(6.859 vs 3.735,P<0.001),liver graft(7.459 vs 3.432,P<0.001),and spleen(26.92 vs 12.9,P<0.001),thereby inhibiting acute rejection after LT.In vitro,5-FU,an end product of CAP metabolism,induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4,which caused the accumulation of ferrous ions.It also inhibited nuclear erythroid 2 p45-related factor 2,heme oxygenase-1,and glutathione peroxidase 4,eventually leading to oxidative damage and ferroptosis of T cells.CONCLUSION Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+T cell ferroptosis,which makes it an effective immunosuppressive agent after LT.
基金supported in part by the Natural Science Foundation of China under Grants 62063004the Key Research Project of Hainan Province under Grant ZDYF2021SHFZ093+1 种基金the Hainan Provincial Natural Science Foundation of China under Grants 2019RC018 and 619QN246the postdoctor research from Zhejiang Province under Grant ZJ2021028.
文摘The amount of 3D data stored and transmitted in the Internet of Medical Things(IoMT)is increasing,making protecting these medical data increasingly prominent.However,there are relatively few researches on 3D data watermarking.Moreover,due to the particularity of medical data,strict data quality should be considered while protecting data security.To solve the problem,in the field of medical volume data,we proposed a robust watermarking algorithm based on Polar Cosine Transform and 3D-Discrete Cosine Transform(PCT and 3D-DCT).Each slice of the volume data was transformed by PCT to obtain feature row vector,and then the reshaped three-dimensional feature matrix was transformed by 3D-DCT.Based on the contour information of the volume data and the detail information of the inner slice,the visual feature vector was obtained by applying the per-ceptual hash.In addition,the watermark was encrypted by a multi-sensitive initial value Sine and Piecewise linear chaotic Mapping(SPM)system,and embedded as a zero watermark.The key was stored in a third party.Under the same experimental conditions,when the volume data is rotated by 80 degrees,cut 25%along the Z axis,and the JPEG compression quality is 1%,the Normalized Correlation Coefficient(NC)of the extracted watermark is 0.80,0.89,and 1.00 respectively,which are significantly higher than the comparison algorithm.
基金supported by the National Natural Science Foundation of China(21676262,21506207,21606221)the Key Research Program of Frontier Sciences,CAS(QYZDB-SSW-JSC040)~~
文摘随着柴油车数量的增加,NO_x污染的控制成为了当今社会的一个重要议题,NO_x可以导致酸雨,光化学烟雾以及慢性健康问题.目前,具有八元环孔口的含铜CHA型分子筛(包括Cu-SSZ-13和Cu-SPAO-34)具有优异的高温水热稳定性及宽温度范围内的活性和N_2选择性,是最具有吸引力的氨选择催化还原催化剂,而且在欧洲和美国已经得到了应用.SAPO-34分子筛的一个重要缺陷就是在100 ℃以下,对水较为敏感,这主要是由于Si–O–Al键的水解造成的.研究表明,在室温下接触水蒸气后,SAPO-34的结晶度和比表面积只能部分恢复,而如果长达数月甚至更长时间的接触后,分子筛将会遭受骨架坍塌等不可逆的破坏,到目前为止,Cu-SAPO-34的低温水热稳定性相关问题并未得到清楚的阐述.本文系统研究了不同铜含量和硅含量的Cu-SAPO-34催化剂的低温水热稳定性.结果显示,低温水热处理后,所有催化剂的NH_3氧化活性和NH_3-SCR活性(主要是低温活性)都有所下降.29Si MAS NMR结果表明,在低温水热处理过程中,骨架结构的破坏在所难免,但催化剂上铜含量的增加有助于Cu-SAPO-34的骨架结构和酸性的更好保持.EPR结果表明,当催化剂上铜含量较低时,孤立Cu^(2+)的稳定性和SAPO分子筛骨架的稳定性呈现正相关的关系.具有较高铜含量(如3.67 wt%)的样品,尽管其骨架结构和酸性在低温水热处理过程中可以得到较好的保持,但活性Cu^(2+)的量仍会有明显的下降.由于部分样品在低温水处理后,NH_3氧化反应活性下降,我们推测CuO颗粒发生了聚结,从而抑制了催化剂的NH_3氧化反应活性,N_2O化学吸附实验也证实了该结论.在所有催化剂中,具有中等铜含量(1.37%)的高硅Cu-SAPO-34样品在低温水处理过程中的Cu^(2+)量和酸性质均得到了较好的保持,所以其水处理后的NH_3-SCR活性衰减最小.
基金supported by the National Key Research and Development Programme of China(Grant No.2016YFC0500406)the Chinese Academy of Sciences Key Strategic Programme,Water Ecological Security Assessment,the Major Research Strategy for Middle and Lower Yangtze River(Grant No.ZDRWZS-2017-3-3)the National Natural Science Foundation of China(Grant Nos.31661143027,31670424,31700330)
文摘Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring.
基金financially supported by the National Natural Science Foundation of China(U1904192,62074052,52072327,61974173,61874159 and 51802081)the Key Science and Technology Research Project of Education Department of Henan Province(19A140003)+1 种基金the Key Science and Technology Program of Henan Province(192102210001)Zhongyuan Thousand Talents(Zhongyuan Scholars)Program of Henan Province(202101510004)。
文摘The development of kesterite photovoltaic solar cells has been hindered by large open-circuit voltage(V_(oc))deficit.Recently,Snzn deep point defect and associative defect cluster have been recognized as the main culprit for the Voc losses.Therefore,manipulating the deep-level donor of Snzn antisite defects is crucial for breaking through the bottleneck of present Cu_(2) ZnSn(S,Se)_(4)(CZTSSe)photovoltaic technology.In this study,the Snzn deep traps in CZTSSe absorber layer are suppressed by incorporation of Ge.The energy levels and concentration of Snzn defects measured by deep-level transient spectroscopy(DLTS)decrease significantly.In addition,the grain growth of CZTSSe films is also promoted due to Ge implantation,yielding the high quality absorber layer.Consequently,the efficiency of CZTSSe solar cells increases from 9.15%to 11.48%,largely attributed to the 41 mV Voc increment.
基金supported by the National Natural Science Foundation of China(Grant No.31870369 and 31970433)China Biodiversity Observation Networks(Sino BON)。
文摘Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field surveys to estimate the species'population size were almost totally conducted in coastal areas,but tracking studies showed that some individuals now winter inland.To ensure its long-term survival,we need a more comprehensive assessment of the current distribution and abundance of the species.Methods:We combined the most recent count data and satellite tracking information to update existing informa-tion about the population abundance and distribution of the Black-faced Spoonbill at all stages of its annual life cycle,and how these have changed during 2004-2020.Results:Black-faced Spoonbills mainly breed on the west coast of the Korean peninsula,while immature birds show a wider summer distribution throughout Yellow Sea coastal areas,when a few remain on wintering sites in the south.Combined tracking results and mid-winter counts confirmed known wintering sites on the east and south coasts of China,but showed that the species also winters on wetlands in the Yangtze River floodplain and in Southeast Asia.During 2004-2020,counts of wintering birds in coastal habitats increased from 1198 to 4864,with numbers wintering on the island of Taiwan contributing most to the overall increase.Latest counts found 5222 in 2021.We also identify key wintering and stopover sites as well as their current conservation status.Conclusions:This study revised the known summering and wintering ranges of the Black-faced Spoonbill and assessed the conservation status of key sites based on a combination of field survey and satellite tracking data.We recommend prioritisation of further field research to identify and survey inland wintering areas in the Yangtze River floodplain and summering areas of immature birds.More tracking of adult individuals and birds during spring migration is necessary to fill these information gaps.We also suggest establishing a Black-faced Spoonbill monitoring platform to store,share and show real-time distribution range and population abundance data.
基金financially supported by the National Natural Science Foundation of China(Nos.21878231,21676202 and 51603145)Natural Science Foundation of Tianjin(Nos.19JCZDJC37300 and 17JCZDJC38100)supported by the Science and Technology Plans of Tianjin(Nos.17PTSYJC00040 and 18PTSYJC00180)。
文摘Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively.
基金supported by National Key Research and Development Program(2016YFC0500406)the National Natural Science Foundation of China(Grant Nos.31661143027,31670424,31870369)+1 种基金the Chinese Academy of Sciences Key Strategic Program,Water Ecological Security Assessment,the Major Research Strategy for Middle and Lower Yangtze River(Grant No.ZDRW-ZS-2017-3-3)China Biodiversity Observation Networks(Sino BON)
文摘Background:Evidence suggests that wintering waterbirds have become conspicuously more concentrated at two largest lakes of the Yangtze River Floodplain,East Dong Ting Lake(Hunan Province,29°20′N,113°E)and Poyang Lake(Jiangxi Province,29°N,116°20′E),relative to other lakes,despite the establishment of reserves elsewhere.While this relationship is likely due to greater extent of undisturbed habitats in larger lakes,we understand little of the drivers affecting individual behaviours behind this tendency.Methods:We tracked wintering movements of three duck species(Eurasian Wigeon Mareca penelope,Falcated Duck M.falcata and Northern Pintail Anas acuta)using GPS transmitters,examining differences between the two largest lakes and other smaller lakes in ducks’habitat use,duration of stay at each lake and the daily distances moved by the tagged birds while at these sites.Results:The Eurasian Wigeon and Falcated Duck stayed five times longer and almost exclusively used natural habitat types at the two large lakes(91‒95%of positions)compared to length of stay time at smaller lakes,where they spent 28‒33 days on average(excluding the capture site)and exploited many more different habitats(including c.50%outside lakes).Conclusions:Our study is the first to show that shorter length of stay and more varied habitat use by ducks at small lakes may contribute to explaining the apparent regional concentration of numbers present of these and other species at the largest lakes in recent years.This compares with their declining abundance at smaller lakes,where habitat loss and degradation has been more manifest than on the larger lakes.
基金Our study was supported by the National Natural Science Foundation of China(Grant No.31870369&No.31970433&No.31670424)China Biodiversity Observation Networks(Sino BON)The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.
文摘Background:The Bar-headed Goose(Anser indicus)breeds across the high plains and plateau of Central Asia and winters in the Qinghai-Tibet Plateau(QTP),the Yunnan-Guizhou Plateau and the Indian sub-continent.Of the two recognized discrete flyways of the Bar-headed Goose,the Eastern Tibetan Flyway(ETF)is the larger,comprising at least six migration routes.However,we remain ignorant about their migratory connectivity,habitat use and effectiveness of site-safeguard mechanisms set in place for the species.Methods:We tracked 30 ETF Bar-headed Geese from Chinese and Mongolian breeding areas to their wintering grounds using GPS/GSM transmitters,to determine their migration routes and stopover staging patterns within the QTP,overlaying these upon GIS layers of protected area status and habitat type,to model their habitat selection.Results:In total,14 tagged Bar-headed Geese provided information on their entire autumn migration and 4 geese on their entire spring migration.Qinghai Lake marked birds overwintered in the QTP(n=2),geese tagged in Mongolia wintered either in the QTP(n=3)or in India/Bangladesh(n=9),representing three of the migration routes within the ETF.In total,tagged birds staged at 79 different stopover sites within QTP in autumn and 23 in spring,of which 65%(autumn)and 59%(spring)of all fixes fell within the boundaries of either National Nature Reserves(NNRs)or Important Birds Areas(IBAs)in the QTP.Bar-headed Geese predominantly occurred on four land-cover types:grassland(mostly by day),water bodies(at night),wetlands and bare substrates(salt flats,dry lake/river substrates and plough)with little change in proportion.Generalized linear mixed models comparing presence with pseudo-absence data suggested geese strongly selected for wetlands as staging habitat,avoiding bare substrates in spring.Conclusions:Based on our limited observations of these tagged geese,this study is the first to show that the current designated National Nature Reserves in place in the staging areas within the QTP appear adequate to protect this increasing population.In addition,Hala Lake in Qinghai Province and adjacent areas used as initial QTP staging during autumn migration(currently outside of designated as NNRs/IBAs)are recommended for protection,based on their use by tagged birds from this study.Habitat modelling confirmed the importance of natural wetlands as feeding areas and safe areas of open water as roosting places.
基金supported by the National Natural Science Foundation of China(Grant Nos.31370416 and 31500315)the State Key Laboratory of Urban and Regional Ecology,Chinese Academy of Sciences(No.SKLURE2013-1-05)the China Biodiversity Observation Network(Sino BON)
文摘Background: Reliable information on the distribution of target species and influencing environmental factors is essential for effective conservation management. However, ecologists have often derived data from costly field surveys. The Swan Goose(Anser cygnoides), a vulnerable Anatidae species, winters almost exclusively in China's Yangtze River floodplain, but wintering numbers have been steadily decreasing. To better safeguard this unique species, modern modeling approaches can be used to quantify and predict its suitable wintering habitat. Specifically, a potential wintering distribution map of this species is critically important.Methods: This study used the maximum entropy approach to model a distribution map of this species. In total, data from 97 up-to-date sites were extracted from 1263 survey sites(excluding duplicate data). After eliminating spatial autocorrelation, 11 environmental variables, including factors related to climate, land structure, vegetation, and anthropogenic activities, were used for model prediction.Results: The prediction distribution map shows that the population has concentrated mainly in the boundary area of Anhui, Hubei, and Jiangxi provinces, especially along the Yangtze River. Modeling results suggest that areas within the middle and lower Yangtze River floodplain, such as those in Hunan and Hubei provinces and the eastern coastal area of Zhejiang Province, demonstrate a potential level of "medium" suitability for this species to winter.Conclusions: Results from this study provide fundamental information for the restoration and management of the Swan Goose. Our "visualized" potential distribution map can assist in planning optimal conservation strategies, and consequently may help to increase the number of wintering populations in China.
基金supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20170922)the Key Strategic Program of the Chinese Academy of Sciences,Water Ecological Security AssessmentGreat Strategy Research of Middle and Lower Yangtze River(Grant No.ZDRW-ZS-2017-3)
文摘Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. For waterfowl foraging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals foraging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) foraging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. Finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at different sediment layers (1–10, 11–20 and 21–30 cm below the surface). Results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese foraged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the first to quantify foraging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on foraging selection of belowground foragers.
基金supported by the National Natural Science Foundation of China,No.81201984the Scientific Research Project of Shaanxi Provincial Health Department in China,No.2010E03the Yulin Municipal Science and Technology Research and Development Project,No.Sf12-06
文摘The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal neurons after injury, but the mechanism by which it affects excitatory synaptic transmission remains poorly understood. Our results showed that diazepam treatment significantly increased the slope of input-output curves in rat neurons after fluid percussion injury. Diazepam significantly decreased the numbers of spikes evoked by super stimuli in the presence of 15 μmol/L bicuculline, indicating the existence of inhibitory pathways in the injured rat hippocampus. Diazepam effectively increased the paired-pulse facilitation ratio in the hippocampal CA1 region following fluid percussion injury, reduced miniature excitatory postsynaptic potentials, decreased action-potential-dependent glutamine release, and reversed spontaneous glutamine release. These data suggest that diazepam could decrease the fluid percussion injury-induced enhancement of excitatory synaptic transmission in the rat hippocampal CA1 area.
基金Science and Technology Key Program of Anhui Province in 2007, No. 07010300199
文摘Some evidence suggests that multiwalled carbon nanotubes can promote neuronal differentiation and growth. The present study investigated the effect of functional multiwalled carbon nanotubes (MWCNTs) on functional recovery of injured sciatic nerves in mice. The results revealed that MWCNTs accelerated the recovery of functional index scores of injured sciatic nerves in mice. Moreover, the medullary sheath was significantly thicker in the injured sciatic nerve following MWCNTs administration. These effects were dose-dependent.