Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken us...Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken using component failure rate data to predict PTC for a full stroke test and a partial stroke test.Given the subjective and uncertain aspects of the FMEDA approach,specifically the selection of component failure rates and the determination of the probability of detecting failure modes,a Fuzzy Inference System(FIS)was proposed to manage the data,addressing the inherent uncertainties.Fuzzy inference systems have been used previously for various FMEA type assessments,but this is the first time an FIS has been employed for use with FMEDA.ESDV PTC values were generated from both the standard FMEDA and the fuzzy-FMEDA approaches using data provided by FMEDA experts.This work demonstrates that fuzzy inference systems can address the subjectivity inherent in FMEDA data,enabling reliable estimates of ESDV proof test coverage for both full and partial stroke tests.This facilitates optimized maintenance planning while ensuring safety is not compromised.展开更多
Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the envi...Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.展开更多
To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials（DFM） for improved animal performance in terms of growth o...To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials（DFM） for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes（i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder） are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi（ARF） based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘generally regarded as safe＇ status for ruminants.展开更多
The restructuring of rural China is one of the most important elements of global social and economic change in the early twenty-first century.From a traditionally rural country,with deep cultural roots in the‘soil’,...The restructuring of rural China is one of the most important elements of global social and economic change in the early twenty-first century.From a traditionally rural country,with deep cultural roots in the‘soil’,China has been transformed into a highly advanced and largely urbanized society within the course of a few decades.The scale and significance of the transformation is equivalent to the industrialization and urbanization of Europe in the nineteenth and early twentieth centuries,and like the European experience a century earlier,its impacts reverberate around the globe.Yet,contemporary China is not Victorian-era Europe and whilst there are parallels,we cannot assume that the trajectories,consequences and responses are the same.展开更多
Drought priming is a promising approach to improve tolerance to further drought in wheat.The root apex plays important roles in drought however,its contribution to drought priming remains unknown.To provide mechanisti...Drought priming is a promising approach to improve tolerance to further drought in wheat.The root apex plays important roles in drought however,its contribution to drought priming remains unknown.To provide mechanistic insights into this process,the transcriptomes and proteomes at three different zones along the root axis under drought stress were analyzed.Physiological assessment of root growth indicated that priming augmented roots growth in response to drought and also the levels of protective proline and glycine betaine.Scanning across the proximal to the distal zones of the root apex indicated increases the transcription of genes involved in primary and secondary metabolism.Conversely,genes related to translation,transcription,folding,sorting and degradation,replication and repair were increased in the apex compared to the proximal zone.A single drought episode suppressed their expression but prior drought priming served to maintain expression with recurrent drought stress.The differentially primed responses genes were mainly involved in the pathways related to plant hormone signaling,stress defense and cell wall modification.The prediction of regulatory hubs using Cytoscape implicated signaling components such as the ABA receptor PYL4 as influencing antioxidant status and the cell cycle.Based our integrative transcriptomic-proteomic assessments we present a model for drought priming protected plant hormone signaling transduction pathways to drive the cell cycle and cell wall loosening to confer beneficial effects on roots to counter the effects of drought.This model provides a theoretical basis for improvement of drought tolerance in wheat,via an increased understanding of drought priming induced drought tolerance.展开更多
This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed gras...This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed grass, whole crop wheat and corn silage total mixed ration. Cows were allocated to one of two experimental treatments: Control (no additive, CON) or 1 g/head/day of EO. Cows were housed in a free stall barn, split into two pens for the duration of the experiment. Two gas data loggers units used to measure CH4 emissions were provided per pen for the duration of the 22 week-long study. Milk yield was determined daily, and milk components were analyzed every two weeks. CH4 was recorded continuously, and daily values were tabulated. Body weight and body condition score were determined at the start and bi-weekly. Results were analyzed as a randomized complete block trial. In total, 149 cows participated in the study (76 CON, 73 EO). Milk yields were greater (P < 0.05) for the test treatment (28.3 CON, 31.2 EO) with no change in milk component concentrations. Milk component concentrations were unaffected (P > 0.05) by treatment. Yields of fat, protein, lactose, and solids were higher for EO fed cows (P 4 output was reduced with the EO compared to the CON treatment (411 g/day vs 438 g/day;13.8 g/L of milk vs 17.2 g/L of milk, P < 0.05) over the duration of the trial. There were no effects of treatment on reproductive performance or the occurrence of mastitis. Feeding EO to dairy cows reduced CH4 emissions whilst also increasing performance.展开更多
Silicon(Si),the second most abundant element in Earth’s crust,exerts beneficial effects on the growth and productivity of a variety of plant species under various environmental conditions.However,the benefits of Si a...Silicon(Si),the second most abundant element in Earth’s crust,exerts beneficial effects on the growth and productivity of a variety of plant species under various environmental conditions.However,the benefits of Si and its importance to plants are controversial due to differences among the species,genotypes,and the environmental conditions.Although Si has been widely reported to alleviate plant drought stress in both the Si-accumulating and nonaccumulating plants,the underlying mechanisms through which Si improves plant water status and maintains water balance remain unclear.The aim of this review is to summarize the morphoanatomical,physiological,biochemical,and molecular processes that are involved in plant water status that are regulated by Si in response to drought stress,especially the integrated modulation of Si-triggered drought stress responses in Si accumulators and intermediate-and excluder-type plants.The key mechanisms influencing the ability of Si to mitigate the effects of drought stress include enhancing water uptake and transport,regulating stomatal behavior and transpirational water loss,accumulating solutes and osmoregulatory substances,and inducing plant defense-associated with signaling events,consequently maintaining whole-plant water balance.This study evaluates the ability of Si to maintain water balance under drought stress conditions and suggests future research that is needed to implement the use of Si in agriculture.Considering the complex relationships between Si and different plant species,genotypes,and the environment,detailed studies are needed to understand the interactions between Si and plant responses under stress conditions.展开更多
Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite l...Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite loci, but compared with the more common shotgun genomic sequencing or transcriptome data, the potential utility of RAD-seq data for microsatellite ascertainment is comparatively under-used.In this study, we employed MiddRAD-seq data to develop polymorphic microsatellite loci for the endangered yew species Taxus florinii. Of 8,823,053 clean reads generated for ten individuals of a population, 94,851(~1%) contained microsatellite motifs. These corresponded to 2993 unique loci, of which 526(~18%) exhibited polymorphism. Of which, 237 were suitable for designing microsatellite primer pairs, and 128 loci were randomly selected for PCR validation and microsatellite screening. Out of the 128 primer pairs, 16 loci gave clear, reproducible patterns, and were then screened and characterized in 24 individuals from two populations. The total number of alleles per locus ranged from two to ten(mean=4.875), and within-population expected heterozygosity from zero to 0.789(mean = 0.530),indicating that these microsatellite loci will be useful for population genetics and speciation studies of T. florinii. This study represents one of few examples to mine polymorphic microsatellite loci from ddRAD data.展开更多
There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-cha...There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO3^2- and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists.展开更多
Seasonally flooded várzea forests of Western Amazonia are one of the most productive and biodiverse wetland forests in the world.However,data on their soil CO_(2)emissions,soil organic matter decomposition rates,...Seasonally flooded várzea forests of Western Amazonia are one of the most productive and biodiverse wetland forests in the world.However,data on their soil CO_(2)emissions,soil organic matter decomposition rates,and soil C stocks are scarce.This is a concern because hydrological changes are predicted to lead to increases in the height,extent,and duration of seasonal floods,which are likely to have a significant effect on soil C stocks and fluxes.However,with no empirical data,the impact of altered flood regimes on várzea soil C cycles remains uncertain.This study quantified the effects of maximum annual flood height and soil moisture on soil CO_(2)efflux rate(R_(s))and soil organic matter decomposition rate(k)in the várzea forests of Pacaya Samiria National Reserve,Peru.The study was conducted between May and August 2017.The results showed that R_(s)(10.6–182.7 mg C m^(-2)h^(-1))and k(0.016–0.078)varied between and within sites,and were considerably lower than the values reported for other tropical forests.In addition,R_(s)was negatively affected by flood height(P<0.01)and soil moisture(P<0.001),and it decreased with decreasing river levels post flooding(P<0.001).In contrast,k was not affected by any of the above-mentioned factors.Soil moisture was the dominant factor influencing R_(s),and it was significantly affected by maximum flood height,even after the floods had subsided(P<0.001).Consequently,we concluded that larger floods will likely lead to reduced R_(s),whilst k could remain unchanged but with decomposition processes becoming more anaerobic.展开更多
The assessment of the fairness of health resource allocation is an important part of the study for the fairness of social development.The data used in most of the existing assessment methods comes from statistical yea...The assessment of the fairness of health resource allocation is an important part of the study for the fairness of social development.The data used in most of the existing assessment methods comes from statistical yearbooks or field survey sampling.These statistics are generally based on administrative areas and are difficult to support a fine-grained evaluation model.In response to these problems,the evaluation method proposed in this paper is based on the query statistics of the geographic grid of the target area,which are more accurate and efficient.Based on the query statistics of hot words in the geographic grids,this paper adopts the maximum likelihood estimation method to estimate the population in the grid region.Then,according to the statistical yearbook data of Hunan province,the estimated number and actual number of hospitals in each grid are analyzed and compared to measure the fairness of health resource allocation in the target region.Experiments show that the geographical grid population assessment based on hot words is more accurate and close to the actual value.The estimated average error is only about 17.8 percent.This method can assess the fairness of health resource allocation in any scale,and is innovative in data acquisition and evaluation methods.展开更多
Titanium germanium intermetallics （TixGey）were directly prepared from titanium oxide （TiO2） and germanium oxide（GeO2） powders mixture by using an electrodeoxidation process. The electrochemical experiment was ca...Titanium germanium intermetallics （TixGey）were directly prepared from titanium oxide （TiO2） and germanium oxide（GeO2） powders mixture by using an electrodeoxidation process. The electrochemical experiment was carried out in a molten fluxCaCl2-NaCl at 800℃ with a potential of 3.0 V. The results show that monolithic germanide Ti5Ge3 intermetallic can be directlyproduced from TiO2-GeO2 or CaTiO3-GeO2 precursors （both molar ratios are 5：3）, and the obtained Ti5Ge3 powders exhibithomogenous particle structure. In addition, the phase composition of the final product can be dramatically affected by the initialmolar ratio of TiO2 to GeO2. The reaction mechanism of the electrodeoxidation process was discussed based on the experimentalresults. It is suggested that the electrodeoxidation process is an environmentally friendly method for the preparation of Ti-Geintermetallics.展开更多
Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three group...Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag （TBFS） mixed with TiO2, and TBFS mixed with high-titanium slag （HTS） were prepared at the same stoichiometric ratio （Ti ： Si = 5 ： 3） corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respec- tively. The pressed porous cylindrical pellet of the Ti/Si-contalning compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane （SOM） based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900--1050℃ and 3.0--4.0V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.展开更多
The present study compared eight breeds of cattle differing in gender （heifers, buls and steers） to determine associations between muscle characteristics and meat sensory qualities of theLongissimus thoracis muscle....The present study compared eight breeds of cattle differing in gender （heifers, buls and steers） to determine associations between muscle characteristics and meat sensory qualities of theLongissimus thoracis muscle. Animal types differed in al the muscle characteristics and sensory qualities. Many correlations among muscle characteristics and among sensory qualities were consistent for most animal types. Isocitrate dehydrogenase （ICDH） activities alowed discrimination of muscles with respect to myosin heavy chain （MyHC）-I proportions for al animal types. Lactate dehydrogenase （LDH） and phos-phofructokinase （PFK） activities were positively correlated for most animal types. Overal liking was correlated with beef lfavour and abnormal lfavour in al animal types and with global tenderness for al animal types except for Charolais cross breed steers. For al animal types except for Angus×Friesian heifers, beef lfavour and abnormal lfavour were negatively correlated. Overal liking was not correlated with juiciness. PFK, ICDH and citrate synthase （CS） activities were strongly associated with tenderness, beef lfavour and overal liking when average values for al animal types were used. However, associations between muscle characteristics and sensory qualities within animal types were weak and inconsistent.展开更多
Ion pickup by a monochromatic low-frequency Alfv6n wave, which propagates along the background magnetic field, has recently been investigated in a low beta plasma （Lu and Li 2007 Phys. Plasmas 14 042303）. In this pa...Ion pickup by a monochromatic low-frequency Alfv6n wave, which propagates along the background magnetic field, has recently been investigated in a low beta plasma （Lu and Li 2007 Phys. Plasmas 14 042303）. In this paper, the monochromatic Alfven wave is generalized to a spectrum of Alfven waves with random phase. It finds that the process of ion pickup can be divided into two stages. First, ions are picked up in the transverse direction, and then phase difference （randomization） between ions due to their different parallel thermal motions leads to heating of the ions. The heating is dominant in the direction perpendicular to the background magnetic field. The temperatures of the ions at the asymptotic stage do not depend on individual waves in the spectrum, but are determined by the total amplitude of the waves. The effect of the initial ion bulk flow in the parallel direction on the heating is also considered in this paper.展开更多
文摘Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken using component failure rate data to predict PTC for a full stroke test and a partial stroke test.Given the subjective and uncertain aspects of the FMEDA approach,specifically the selection of component failure rates and the determination of the probability of detecting failure modes,a Fuzzy Inference System(FIS)was proposed to manage the data,addressing the inherent uncertainties.Fuzzy inference systems have been used previously for various FMEA type assessments,but this is the first time an FIS has been employed for use with FMEDA.ESDV PTC values were generated from both the standard FMEDA and the fuzzy-FMEDA approaches using data provided by FMEDA experts.This work demonstrates that fuzzy inference systems can address the subjectivity inherent in FMEDA data,enabling reliable estimates of ESDV proof test coverage for both full and partial stroke tests.This facilitates optimized maintenance planning while ensuring safety is not compromised.
基金funded by UK Research and Innovation(UKRI)doctoral training grant no:BB/T008776/1the Department of Agriculture,Environment and Rural Affairs(DAERA)by Trouw Nutrition and by John Thompsons and Sons Ltd.
文摘Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.
基金financial support provided under the Network Project of ICAR on ‘VTCC’ to carry the research further in this direction
文摘To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials（DFM） for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes（i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder） are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi（ARF） based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘generally regarded as safe＇ status for ruminants.
文摘The restructuring of rural China is one of the most important elements of global social and economic change in the early twenty-first century.From a traditionally rural country,with deep cultural roots in the‘soil’,China has been transformed into a highly advanced and largely urbanized society within the course of a few decades.The scale and significance of the transformation is equivalent to the industrialization and urbanization of Europe in the nineteenth and early twentieth centuries,and like the European experience a century earlier,its impacts reverberate around the globe.Yet,contemporary China is not Victorian-era Europe and whilst there are parallels,we cannot assume that the trajectories,consequences and responses are the same.
基金supported by the National Key Research and Development Program of China (2016YFD0300107)the National Natural Science Foundation of China (31771693, U1803235)+3 种基金the China Agriculture Research System (CARS-03)JCIC-MCPthe 111 Project (B16026)the UK Biotechnology and Biological Sciences Research Council (BBSRC) Exchange Grant (BB/R02118X/1)。
文摘Drought priming is a promising approach to improve tolerance to further drought in wheat.The root apex plays important roles in drought however,its contribution to drought priming remains unknown.To provide mechanistic insights into this process,the transcriptomes and proteomes at three different zones along the root axis under drought stress were analyzed.Physiological assessment of root growth indicated that priming augmented roots growth in response to drought and also the levels of protective proline and glycine betaine.Scanning across the proximal to the distal zones of the root apex indicated increases the transcription of genes involved in primary and secondary metabolism.Conversely,genes related to translation,transcription,folding,sorting and degradation,replication and repair were increased in the apex compared to the proximal zone.A single drought episode suppressed their expression but prior drought priming served to maintain expression with recurrent drought stress.The differentially primed responses genes were mainly involved in the pathways related to plant hormone signaling,stress defense and cell wall modification.The prediction of regulatory hubs using Cytoscape implicated signaling components such as the ABA receptor PYL4 as influencing antioxidant status and the cell cycle.Based our integrative transcriptomic-proteomic assessments we present a model for drought priming protected plant hormone signaling transduction pathways to drive the cell cycle and cell wall loosening to confer beneficial effects on roots to counter the effects of drought.This model provides a theoretical basis for improvement of drought tolerance in wheat,via an increased understanding of drought priming induced drought tolerance.
文摘This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed grass, whole crop wheat and corn silage total mixed ration. Cows were allocated to one of two experimental treatments: Control (no additive, CON) or 1 g/head/day of EO. Cows were housed in a free stall barn, split into two pens for the duration of the experiment. Two gas data loggers units used to measure CH4 emissions were provided per pen for the duration of the 22 week-long study. Milk yield was determined daily, and milk components were analyzed every two weeks. CH4 was recorded continuously, and daily values were tabulated. Body weight and body condition score were determined at the start and bi-weekly. Results were analyzed as a randomized complete block trial. In total, 149 cows participated in the study (76 CON, 73 EO). Milk yields were greater (P < 0.05) for the test treatment (28.3 CON, 31.2 EO) with no change in milk component concentrations. Milk component concentrations were unaffected (P > 0.05) by treatment. Yields of fat, protein, lactose, and solids were higher for EO fed cows (P 4 output was reduced with the EO compared to the CON treatment (411 g/day vs 438 g/day;13.8 g/L of milk vs 17.2 g/L of milk, P < 0.05) over the duration of the trial. There were no effects of treatment on reproductive performance or the occurrence of mastitis. Feeding EO to dairy cows reduced CH4 emissions whilst also increasing performance.
基金This work was financially supported by the National Key R&D Program(2016YFD0200900)the Fundamental Research Funds for the Central Universities(KYGD202007)+1 种基金the National Natural Science Foundation of China(32072673)the Young Elite Scientists Sponsorship Program by CAST(2018QNRC001).
文摘Silicon(Si),the second most abundant element in Earth’s crust,exerts beneficial effects on the growth and productivity of a variety of plant species under various environmental conditions.However,the benefits of Si and its importance to plants are controversial due to differences among the species,genotypes,and the environmental conditions.Although Si has been widely reported to alleviate plant drought stress in both the Si-accumulating and nonaccumulating plants,the underlying mechanisms through which Si improves plant water status and maintains water balance remain unclear.The aim of this review is to summarize the morphoanatomical,physiological,biochemical,and molecular processes that are involved in plant water status that are regulated by Si in response to drought stress,especially the integrated modulation of Si-triggered drought stress responses in Si accumulators and intermediate-and excluder-type plants.The key mechanisms influencing the ability of Si to mitigate the effects of drought stress include enhancing water uptake and transport,regulating stomatal behavior and transpirational water loss,accumulating solutes and osmoregulatory substances,and inducing plant defense-associated with signaling events,consequently maintaining whole-plant water balance.This study evaluates the ability of Si to maintain water balance under drought stress conditions and suggests future research that is needed to implement the use of Si in agriculture.Considering the complex relationships between Si and different plant species,genotypes,and the environment,detailed studies are needed to understand the interactions between Si and plant responses under stress conditions.
基金funded by the National Natural Science Foundations of China (31370252, 41571059)the National Key Basic Research Program of China (2014CB954100)supported by the China Scholarship Council for one-year study at the Aberystwyth University,UK
文摘Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite loci, but compared with the more common shotgun genomic sequencing or transcriptome data, the potential utility of RAD-seq data for microsatellite ascertainment is comparatively under-used.In this study, we employed MiddRAD-seq data to develop polymorphic microsatellite loci for the endangered yew species Taxus florinii. Of 8,823,053 clean reads generated for ten individuals of a population, 94,851(~1%) contained microsatellite motifs. These corresponded to 2993 unique loci, of which 526(~18%) exhibited polymorphism. Of which, 237 were suitable for designing microsatellite primer pairs, and 128 loci were randomly selected for PCR validation and microsatellite screening. Out of the 128 primer pairs, 16 loci gave clear, reproducible patterns, and were then screened and characterized in 24 individuals from two populations. The total number of alleles per locus ranged from two to ten(mean=4.875), and within-population expected heterozygosity from zero to 0.789(mean = 0.530),indicating that these microsatellite loci will be useful for population genetics and speciation studies of T. florinii. This study represents one of few examples to mine polymorphic microsatellite loci from ddRAD data.
基金The Open Foundation of Laboratory of Marine Ecosystem and Biogeochemistry,SOA under contract No.LMEB201701
文摘There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO3^2- and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists.
基金supported by Department of Geography and Earth Sciences(DGES)and Institute of Biological,Environmental and Rural Sciences(IBERS)at Aberystwyth University,Wales of UK。
文摘Seasonally flooded várzea forests of Western Amazonia are one of the most productive and biodiverse wetland forests in the world.However,data on their soil CO_(2)emissions,soil organic matter decomposition rates,and soil C stocks are scarce.This is a concern because hydrological changes are predicted to lead to increases in the height,extent,and duration of seasonal floods,which are likely to have a significant effect on soil C stocks and fluxes.However,with no empirical data,the impact of altered flood regimes on várzea soil C cycles remains uncertain.This study quantified the effects of maximum annual flood height and soil moisture on soil CO_(2)efflux rate(R_(s))and soil organic matter decomposition rate(k)in the várzea forests of Pacaya Samiria National Reserve,Peru.The study was conducted between May and August 2017.The results showed that R_(s)(10.6–182.7 mg C m^(-2)h^(-1))and k(0.016–0.078)varied between and within sites,and were considerably lower than the values reported for other tropical forests.In addition,R_(s)was negatively affected by flood height(P<0.01)and soil moisture(P<0.001),and it decreased with decreasing river levels post flooding(P<0.001).In contrast,k was not affected by any of the above-mentioned factors.Soil moisture was the dominant factor influencing R_(s),and it was significantly affected by maximum flood height,even after the floods had subsided(P<0.001).Consequently,we concluded that larger floods will likely lead to reduced R_(s),whilst k could remain unchanged but with decomposition processes becoming more anaerobic.
文摘The assessment of the fairness of health resource allocation is an important part of the study for the fairness of social development.The data used in most of the existing assessment methods comes from statistical yearbooks or field survey sampling.These statistics are generally based on administrative areas and are difficult to support a fine-grained evaluation model.In response to these problems,the evaluation method proposed in this paper is based on the query statistics of the geographic grid of the target area,which are more accurate and efficient.Based on the query statistics of hot words in the geographic grids,this paper adopts the maximum likelihood estimation method to estimate the population in the grid region.Then,according to the statistical yearbook data of Hunan province,the estimated number and actual number of hospitals in each grid are analyzed and compared to measure the fairness of health resource allocation in the target region.Experiments show that the geographical grid population assessment based on hot words is more accurate and close to the actual value.The estimated average error is only about 17.8 percent.This method can assess the fairness of health resource allocation in any scale,and is innovative in data acquisition and evaluation methods.
基金Project(51574164)supported by the National Natural Science Foundation of ChinaProject(2014CB643403)supported by the National Basic Research Program of China
文摘Titanium germanium intermetallics （TixGey）were directly prepared from titanium oxide （TiO2） and germanium oxide（GeO2） powders mixture by using an electrodeoxidation process. The electrochemical experiment was carried out in a molten fluxCaCl2-NaCl at 800℃ with a potential of 3.0 V. The results show that monolithic germanide Ti5Ge3 intermetallic can be directlyproduced from TiO2-GeO2 or CaTiO3-GeO2 precursors （both molar ratios are 5：3）, and the obtained Ti5Ge3 powders exhibithomogenous particle structure. In addition, the phase composition of the final product can be dramatically affected by the initialmolar ratio of TiO2 to GeO2. The reaction mechanism of the electrodeoxidation process was discussed based on the experimentalresults. It is suggested that the electrodeoxidation process is an environmentally friendly method for the preparation of Ti-Geintermetallics.
基金the National Natural Science Foundation of China(No.51074105)the China Postdoctoral Science Foundation(No.2012M520873)China National Funds for Distinguished Young Scientists (No.51225401)
文摘Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag （TBFS） mixed with TiO2, and TBFS mixed with high-titanium slag （HTS） were prepared at the same stoichiometric ratio （Ti ： Si = 5 ： 3） corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respec- tively. The pressed porous cylindrical pellet of the Ti/Si-contalning compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane （SOM） based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900--1050℃ and 3.0--4.0V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.
基金the framework of the EU Project ProSafeBeef(FOOD-CT-2006-36241)with INRA(Institut National de la Recherche Agronomique,France)Quality Assurance number AQ284
文摘The present study compared eight breeds of cattle differing in gender （heifers, buls and steers） to determine associations between muscle characteristics and meat sensory qualities of theLongissimus thoracis muscle. Animal types differed in al the muscle characteristics and sensory qualities. Many correlations among muscle characteristics and among sensory qualities were consistent for most animal types. Isocitrate dehydrogenase （ICDH） activities alowed discrimination of muscles with respect to myosin heavy chain （MyHC）-I proportions for al animal types. Lactate dehydrogenase （LDH） and phos-phofructokinase （PFK） activities were positively correlated for most animal types. Overal liking was correlated with beef lfavour and abnormal lfavour in al animal types and with global tenderness for al animal types except for Charolais cross breed steers. For al animal types except for Angus×Friesian heifers, beef lfavour and abnormal lfavour were negatively correlated. Overal liking was not correlated with juiciness. PFK, ICDH and citrate synthase （CS） activities were strongly associated with tenderness, beef lfavour and overal liking when average values for al animal types were used. However, associations between muscle characteristics and sensory qualities within animal types were weak and inconsistent.
基金supported by the National Natural Science Foundation of China(Grants Nos 40725013 and 40674093)Chinese Academy of Sciences(Grant No KJCX2-YW-N28 9140C08060507ZCZJ19)
文摘Ion pickup by a monochromatic low-frequency Alfv6n wave, which propagates along the background magnetic field, has recently been investigated in a low beta plasma （Lu and Li 2007 Phys. Plasmas 14 042303）. In this paper, the monochromatic Alfven wave is generalized to a spectrum of Alfven waves with random phase. It finds that the process of ion pickup can be divided into two stages. First, ions are picked up in the transverse direction, and then phase difference （randomization） between ions due to their different parallel thermal motions leads to heating of the ions. The heating is dominant in the direction perpendicular to the background magnetic field. The temperatures of the ions at the asymptotic stage do not depend on individual waves in the spectrum, but are determined by the total amplitude of the waves. The effect of the initial ion bulk flow in the parallel direction on the heating is also considered in this paper.
