Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 -...Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 - 18. Methods: From September 2005 to December 2011, comprehensive physical fitness assessments were conducted on 12,712 school students. The SLJ performances were significantly different between boys and girls (all age groups, p < 0.01). Results: The boys performed better than the girls in each age group. The mean difference increased as the age increased, depicting a prominent variance in muscular strength between boys and girls at age 12, and the variances became larger at age 18. Girls in the 70th percenttile performed similarly to boys performing in the 10th percentile. The onset of muscle strength for boys found in this study corresponded to the onset age of testosterone maturation of Chinese boys investigated in previous studies. Linear regression found age and BMI predicting SLJ significantly for boys and girls, explaining better SLJ results in older boy and the effect of their heavy body size. Conclusions: This study indicated a muscular strength difference between genders during growth and added supporting evidence to the hormonal influence of muscle growth during puberty.展开更多
Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint ...Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a5-m wavelength range, leaving a significant knowledge gap in this field.Design/methodology/approach – In this study, the authors used the well-established inertial referencemethod (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methodshave been applied in different types of rail straightness measurement trollies, respectively. These instrumentswere tested in a high-speed rail section within a certain region of China. The test results were ultimatelyvalidated through using traditional straightedge and feeler gauge methods as reference data to evaluate the railweld joint straightness within the 5-m wavelength range.Findings – The research reveals that IR-method and MCR-method produce reasonably similar measurementresults for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy forwavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed,carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.Originality/value – The research compare two methods’ measurement effects in a longer wavelength rangeand demonstrate the superiority of MCR-method.展开更多
The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristic...The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristics of the operated patients, to determine the main pathologies encountered and to evaluate qualitatively the result of the treatment. In order to improve performance, and the quality of care, and to identify common pathologies in the surgical department, we undertook a retrospective study on surgical activities from January 2009 to December 2010. At the end of this study, out of 474 men and 187 women (equal sex ratio 2.53);we were able to determine the frequency of surgical pathologies. Farmers, housewives and pupils/students were the most represented with 25.9% respectively;20% and 13.3%. The most frequently observed pathologies were wall hernia (44.8%), prostate adenoma (12%) and acute appendicitis (10.5%). The average length of hospitalization was 3.43 days. Infectious complications affected 25 patients (3.8% of cases) and a death rate of 0.45% (i.e. 3 patients). The average cost of care was 53,500 FCFA. Indeed, the reality of surgical practice in health centers was not the same because of the level of skills of practicing surgeons.展开更多
Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small...Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection.展开更多
Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aime...Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting.展开更多
Background:Acute pancreatitis(AP)is a severe disorder that leads to high morbidity and mortality.Appropriate reference genes are important for gene analysis in AP.This study sought to study the expression stability of...Background:Acute pancreatitis(AP)is a severe disorder that leads to high morbidity and mortality.Appropriate reference genes are important for gene analysis in AP.This study sought to study the expression stability of several reference genes in the golden Syrian hamster,a model of AP.Methods:AP was induced in golden Syrian hamster by intraperitoneal injection of ethanol(1.35 g/kg)and palmitoleic acid(2 mg/kg).The expression of candidate genes,including Actb,Gapdh,Eef2,Ywhaz,Rps18,Hprt1,Tubb,Rpl13a,Nono,and B2m,in hamster pancreas at different time points(1,3,6,9,and 24 h)posttreatment was analyzed using quantitative polymerase chain reaction.The expression stability of these genes was calculated using Best Keeper,Comprehensive Delta CT,Norm Finder,and ge Norm algorithms and Ref Finder software.Results:Our results show that the expression of these reference genes fluctuated during AP,of which Ywhaz and Gapdh were the most stable genes,whereas Tubb,Eef2,and Actb were the least stable genes.Furthermore,these genes were used to normalize the expression of TNF-αmessenger ribonucleic acid in inflamed pancreas.Conclusions:In conclusion,Ywhaz and Gapdh were suitable reference genes for gene expression analysis in AP induced in Syrian hamster.展开更多
Quantitative real-time PCR(qRT-PCR)has been widely used for gene expression analysis,and selection of reference genes is a key point to obtain accurate results.To find out optimal reference genes for qRT-PCR in Manila...Quantitative real-time PCR(qRT-PCR)has been widely used for gene expression analysis,and selection of reference genes is a key point to obtain accurate results.To find out optimal reference genes for qRT-PCR in Manila clam Ruditapes philippinarum in response to hypoxia,different tissues were used and compared to evaluate the stability of candidate reference genes under low oxygen stress(DO 0.5mgL^(−1) and DO 2.0mgL^(−1))and normal condition(DO 7.5mgL^(−1)).Seven candidate reference genes were selected to evaluate the stability of their expression levels.The reference genes were evaluated by Delta Ct,BestKeeper,NormFinder and geNorm,and then screened by RefFinder calculation.Under hypoxic stress of 0.5mgL^(−1),the most suitable reference gene for gill and hepatopancreas was RPL31,and the optimal reference genes for axe foot and adductor muscle were TUB and HIS,respectively.For hypoxic stress of 2.0mgL^(−1),the most stable reference gene for gill and hepatopancreas was RPL31,and the optimal reference genes for axe foot and adductor muscle were RPS23 and EF1A,respectively.At the normal condition,HIS and EF1A were identified as the optimal internal reference genes in gill and hepatopancreas respectively,and GFRP2 was the best internal reference gene for axe foot and adductor muscle.The present findings will provide important basis for the selection of reference genes for qRT-PCR analysis of gene expression level in bivalves under hypoxic stress,which might be helpful for the analysis of other molluscs too.展开更多
Leopard coral groupers(Plectropomus leopardus),commercially bred in South China,are a significant economical fish species.In this study,by means of quantitative real-time PCR(qRT-PCR)technology,we assessed the stabili...Leopard coral groupers(Plectropomus leopardus),commercially bred in South China,are a significant economical fish species.In this study,by means of quantitative real-time PCR(qRT-PCR)technology,we assessed the stability of six common reference genes expression and selected the appropriate reference genes in leopard coral groupers with or without Vibrio harveyi stimulation at different time points.These data produced by qRT-PCR was handled via the geNorm,NormFinder,and BestKeeper software.The results revealed all the examined reference genes had manifest tissue-specific expression in different tissues.Prior to V.harveyi stimulation,RPL13 gene was the appropriate reference gene among eleven tissue types(blood,spleen,hepatopancreas,kidney,stomach,gill,heart,skin,muscle,intestine,brain)in leopard coral groupers.Under V.harveyi stimulation,the most reliable reference genes varied from tissue to tissue and were closely hinged upon different time points.At 6-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were Actin,B2M,UBCE,and Actin,respectively.At 9-and 12-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were RPL13,Actin,Actin,and Actin,respectively.If one reference gene was preferable,RPL13,Actin,Actin,and Actin could be selected as the reference gene in hepatopancreas,spleen,kidney,and gill of leopard coral groupers after V.harveyi infection,respectively.Expression profiles of two target genes(IL-6 and NK-lysin)were used to further validate reliability of these selected appropriate candidates.This study will lay a solid foundation for the future research on qRTPCR analysis of gene expression in leopard coral groupers.展开更多
Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its c...Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.展开更多
The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected fiv...The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected five commonly used housekeeping genes,including β-actin,Elongation factor 1-α(EF1-α),Glyceraldehyde-3-pho sphate dehydrogenase(GAPDH),40S ribosomal protein S18(RPS18),and Tubulin a(TUB-α),then evaluated their expression stability in different adult tissues and under different experimental treatments(salinity stress and Vibrio parahaemolyticus infection).Their expression stability was analyzed by three frequently used programs,geNorm,NormFinder,and BestKeeper.This analysis indicated that multiple genes should be used for normalization,and we concluded that the reference gene combination GAPDH-RPS18-β-actin,should be used for qRT-PCR analysis in different tissues of C.sinensis under normal physiological conditions.For the clams under salinity stress and Vibrio infection,EF1-α-GAPDHRPS18 was recommended as the gene combination for qRT-PCR normalization.TUB-αwas generally poorly ranked by all programs,and should not be used in future studies.This study should provide fundamental support for accurate quantitative gene expression analysis of this species.展开更多
Background: Niger is one of the countries that have the highest fertility rate in the world, with 7, 6 children per woman. Zinder is the most populated region of Niger with 5 million inhabitants that is 1/5 of Niger p...Background: Niger is one of the countries that have the highest fertility rate in the world, with 7, 6 children per woman. Zinder is the most populated region of Niger with 5 million inhabitants that is 1/5 of Niger population. The demographic impact that has affected Niger the last 10 years: unemployment poverty and drug use, spawned violence of all kinds in Zinder region (physical and sexual violence). Sexual abuse is a major risk for poor psychiatric and physical outcomes. As sexual violence has serious consequences on the life and future of women and the community and it concerns our field of intervention, we initiated this study whose objective was to determine the socio-epidemiological and lesional aspects, the consequences and appropriate solutions of sexual violence in the Zinder. Methodology: This was a retrospective collection study of all cases of alleged sexual violence received over a 12-year period from 1 January 2009 to 30 June 2021 in Zinder’s referral maternity wards. Results: During the study period, 441 cases of sexual violence were collected;an annual average of 36 cases (441/12). The frequency is 1.29% on the 34,186 consultations. The mean age was 12.31 years with age extremes of 3 to 43 years. Students accounted for 25.39%. Street vendors were found in 224 cases or 50.79%. The predominant reason for admission is rape in 64.63%. The defloration was 52.15%. Pregnancy was found in 118 cases or 26.75%. HIV serology was positive in 1 victim. School dropout was 26.75%. Conclusion: The victims of sexual violence were minors, mostly street vendors and school children. The lack of means of repression at the time allowed the expansion of this violence. The consequences of sexual violence were severe. Advocacy has improved the phenomen on of sexual violence in Zinder.展开更多
Natural gas (NG) is one of the most important sources of energy for industrial and domestic consumption in the present era because it is cheap and free from sulfur impurities. Therefore, accurate and precise measureme...Natural gas (NG) is one of the most important sources of energy for industrial and domestic consumption in the present era because it is cheap and free from sulfur impurities. Therefore, accurate and precise measurement of its composition is of fundamental importance for trade reasons. To improve the quality of NG gas measurements, certified reference materials (CRMs) should be used for calibration of measuring equipment in order to ensure the traceability of the measurement results to the SI units. For the traceability purpose, a multicomponent natural gas mixture was prepared gravimetrically as a reference material according to ISO 6142 from pure helium, hydrogen, n-pentane, i-pentane, n-butane, i-butane, propane, ethane, hexane, methane and nitrogen. The preparation was done in two dilution steps in 5 L aluminum cylinders. The calculated mole fractions and associated uncertainties of natural gas components were verified by a dual GC-FID/TCD system in accordance with ISO 6143 calibrated by a series of primary gas mixtures (CRMs) produced by an NMI. The results obtained by gravimetry and by GC measurements have been checked for compatibility as required by ISO 6142 and were found in very good agreement. Details of the preparation and calculation of the mole fractions and uncertainties of all gas components are explained in this article.展开更多
The extraction and understanding of text knowledge become increasingly crucial in the age of big data.One of the current research areas in the field of natural language processing(NLP)is how to accurately understand t...The extraction and understanding of text knowledge become increasingly crucial in the age of big data.One of the current research areas in the field of natural language processing(NLP)is how to accurately understand the text and collect accurate linguistic information because Chinese vocabulary is diverse and ambiguous.This paper mainly studies the candidate entity generation module of the entity link system.The candidate entity generation module constructs an entity reference expansion algorithm to improve the recall rate of candidate entities.In order to improve the efficiency of the connection algorithm of the entire system while ensuring the recall rate of candidate entities,we design a graph model filtering algorithm that fuses shallow semantic information to filter the list of candidate entities,and verify and analyze the efficiency of the algorithm through experiments.By analyzing the related technology of the entity linking algorithm,we study the related technology of candidate entity generation and entity disambiguation,improve the traditional entity linking algorithm,and give an innovative and practical entity linking model.The recall rate exceeds 82%,and the link accuracy rate exceeds 73%.Efficient and accurate entity linking can help machines to better understand text semantics,further promoting the development of NLP and improving the users’knowledge acquisition experience on the text.展开更多
Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the gr...Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the growth and development of P.lactiflora.Quantitative real-time polymerase chain reaction(qRT-PCR)can evaluate gene expression levels under different stress conditions,and stable internal reference is the key for qRT-PCR.At present,there is no systematic screening of internal reference for correcting gene expressions of P.lactiflora in response to drought stress.In this study,10 candidate genes[ubiquitin(UBQ2),UBQ1,elongation factor 1-α(EF-1α),Histidine(His),eukaryotic initiation factor(eIF),tubulin(TUB),actin(ACT),UBQ3,ACT2,RNA polymerase II(RNA Pol II)]were chosen,and 4 analysis methods were used to compare the stabilities for these 10 genes coping with drought stress.Due to the difference of operation methods,the results of different analysis were distinct,and the final comprehensive analysis indicated that EF-1αwas a relatively stable internal reference gene for P.lactiflora under drought stress.Also,UBQ1 and UBQ2 were the best reference gene combination according to GeNorm analysis.This study will lay a foundation for screening the key genes of P.lactiflora in response to drought stress.展开更多
Objectives: The aim of this work was to initially establish both age and weight driven pediatric diagnostic reference levels (DRLs) for chest computed tomography (CT) examinations performed at tertiary care medical in...Objectives: The aim of this work was to initially establish both age and weight driven pediatric diagnostic reference levels (DRLs) for chest computed tomography (CT) examinations performed at tertiary care medical institution. Another aim was to compare the presented data with internationally published ones. This initial data shall serve as basis for establishing a national DRLs values for pediatric diagnostic CT examinations. Methods: Dosimetric indexes were collected for the chest examination for 93 patients during the past 2 years in a tertiary care medical city. Results: The results are within and below the international reported levels for chest CT in several countries. Conclusion: Continuous monitoring of the radiation doses received by the patients in computed tomography is continuous and ongoing process in order to ensure compliance and to optimize clinical imaging protocols. More extensive data acquisition and analysis are required to allow better understanding of the contributing factors leading to less patient radiation dose while preserving the clinical image quality. .展开更多
This paper proposes an improved exponential curvature-compensated bandgap reference circuit to exploit the exponential relationship between the current gainβof the bipolar junction transistor(BJT)and the temperature ...This paper proposes an improved exponential curvature-compensated bandgap reference circuit to exploit the exponential relationship between the current gainβof the bipolar junction transistor(BJT)and the temperature as well as reduce the influence of resistance-temperature dependency.Considering the degraded circuit performance caused by the process deviation,the trimmable module of the temperature coefficient(TC)is introduced to improve the circuit stability.The circuit has the advantages of simple structure,high linear stability,high TC accuracy,and trimmable TC.It consumes an area of 0.09 mm^(2)when fabricated by using the 0.25-μm complementary metal-oxide-semiconductor(CMOS)process.The proposed circuit achieves the simulated power supply rejection(PSR)of about-78.7 dB@1 kHz,the measured TC of~4.7 ppm/℃over a wide temperature range from-55℃to 125℃with the 2.5-V single-supply voltage,and the tested line regulation of 0.10 mV/V.Such a high-performance bandgap reference circuit can be widely applied in high-precision and high-reliability electronic systems.展开更多
Background: Acute intoxications result from intentionally or accidentally taking a relatively significant amount of a chemical substance which triggers disturbances in the level of psychophysiological functions, the c...Background: Acute intoxications result from intentionally or accidentally taking a relatively significant amount of a chemical substance which triggers disturbances in the level of psychophysiological functions, the complications of which may lead to mental disorders, physical causalities, and death. Any acute intoxication mostly requires emergency care. Objective: To highlight the prevalence, history, clinical features, emergency treatment, and prediction of acute intoxication cases referred to the emergency services at the Provincial General Reference Hospital in Bukavu, DR-Congo. Methods: A retrospective cross-sectional study was conducted from January 2021 to October 2022 based on an analysis of patients’ medical files. Triage was performed among all-type of patient files recorded in the computerized hospital database Ebale-Sante to sort cases of intoxication. Results: During the observational period, 3966 emergency admissions were counted, of which 321 (8.09%) patients were identified as having acute intoxication. Among these, 100 files that containing sufficient information fit the quality criteria for this study’s analysis. The victims were infants, adolescents and adults aged 1 - 45 years, and 52% were female and 48% were male. Most cases were accidental and, occurred at home, and the victims were driven to the hospital within 2 - 24 hours. The substances consumed included household products, drugs, and herbs. Resuscitation care, antidotes and supportive symptomatic medications ensured that 85% were healed and 10% experienced sequelae;however, 5% died. Conclusion: Acute intoxication occurs in infants mostly accidentally though the ingestion of household products and medicines. Furthermore, suicide cases may occur in traumatized adolescents and discordant couples. People should be informed about how to store hazardous products (e.g.: drugs, household products and pesticides), which should not be available to children, to avoid unintentional poisoning. Special training in clinical toxicology is required to reduce treatment failure.展开更多
The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,cal...The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,called for a seismological reference model to be established in China.The China Seismological Reference Model(CSRM)project was initiated by the National Natural Science Foundation of China with two primary goals:(1)the CSRM would serve as a primary source for the current state of seismological research in China,and(2)the seismic data and constraints used to construct the CSRM would be used as a backbone open-access cyberinfrastructure for future research in seismology.The CSRM project was also intended to promote data exchange and scientific collaboration in seismology in China.Accordingly,two parallel efforts of the project are being pursued:(1)construction of the CSRM,and(2)development of a CSRM product center.The CSRM is jointly constrained by various types of seismic constraints extracted from the seismic data recorded at 4511 seismic stations in continental China following a top-down approach,with the seismic structures in the shallower part of the Earth constrained first.Construction of the CSRM involves three preparation steps:(1)building datasets of various seismic constraints from the seismic data,(2)developing a method to incorporate the constraints of surface wave observations from regional earthquakes into the inversion of the seismic structure,and(3)constructing high-resolution pre-CSRM seismic models of the velocity structure in the shallow crust and the Pn-velocity structure in the uppermost mantle.In the final process,the CSRM will be constructed by jointly inverting all the seismic constraints using the pre-CSRM models as starting models or a priori structures.The CSRM product center(http://chinageorefmodel.org)archives and distributes three types of products:CSRM models,the Level 1 original seismic data used to extract seismic constraints in the construction of the CSRM,and Level 2 data on the seismic constraints derived from the Level 1 data and the inferred earthquake parameters in the construction of the CSRM.The CSRM product center has archived 141 TB of Level 1 data from 1120 permanent broadband stations in the China Seismic Network Center and 3391 temporary stations from various institutions and data centers around the world,as well as 140 GB of Level 2 data on various seismic constraints and inferred event parameters from the construction of the CSRM.The CSRM is expected to provide significant insights into the composition and tectonic dynamics in continental China and to enhance the capability of various seismic hazard mitigation programs in China from near real-time rapid determination of earthquake parameters to an earthquake early warning system.The CSRM could also provide guidance for focuses in future seismological research and the design of future active and passive seismic experiments in China.Several focuses are suggested for future seismological research in China,along with the building of a national cyberinfrastructure to sustain and expand the operations of the CSRM project.展开更多
Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the charact...Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the characteristics of drought events.Studying precipitation,reference evapotranspiration(ET_(0)),and vegetation yield can derive information to help conserve water resources in grassland ecosystems in arid and semi-arid regions.In this study,the interactions of precipitation,ET_(0),and vegetation yield in Darhan Muminggan Joint Banner(DMJB),a desert steppe in Inner Mongolia Autonomous Region,China were explored using two-dimensional(2D)and three-dimensional(3D)joint distribution models.Three types of Copula functions were applied to quantitatively analyze the joint distribution probability of different combinations of precipitation,ET_(0),and vegetation yield.For the precipitation–ET_(0)dry–wet type,the 2D joint distribution probability with precipitation≤245.69 mm/a or ET_(0)≥959.20 mm/a in DMJB was approximately 0.60,while the joint distribution probability with precipitation≤245.69 mm/a and ET_(0)≥959.20 mm/a was approximately 0.20.Correspondingly,the joint return period that at least one of the two events(precipitation was dry or ET_(0)was wet)occurred was 2 a,and the co-occurrence return period that both events(precipitation was dry and ET_(0)was wet)occurred was 5 a.Under this condition,the interval between dry and wet events would be short,the water supply and demand were unbalanced,and the water demand of vegetation would not be met.In addition,when precipitation remained stable and ET_(0)increased,the 3D joint distribution probability that vegetation yield would decrease due to water shortage in the precipitation–ET_(0)dry–wet years could reach up to 0.60–0.70.In future work,irrigation activities and water allocation criteria need to be implemented to increase vegetation yield and the safety of water resources in the desert steppe of Inner Mongolia.展开更多
文摘Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 - 18. Methods: From September 2005 to December 2011, comprehensive physical fitness assessments were conducted on 12,712 school students. The SLJ performances were significantly different between boys and girls (all age groups, p < 0.01). Results: The boys performed better than the girls in each age group. The mean difference increased as the age increased, depicting a prominent variance in muscular strength between boys and girls at age 12, and the variances became larger at age 18. Girls in the 70th percenttile performed similarly to boys performing in the 10th percentile. The onset of muscle strength for boys found in this study corresponded to the onset age of testosterone maturation of Chinese boys investigated in previous studies. Linear regression found age and BMI predicting SLJ significantly for boys and girls, explaining better SLJ results in older boy and the effect of their heavy body size. Conclusions: This study indicated a muscular strength difference between genders during growth and added supporting evidence to the hormonal influence of muscle growth during puberty.
文摘Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a5-m wavelength range, leaving a significant knowledge gap in this field.Design/methodology/approach – In this study, the authors used the well-established inertial referencemethod (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methodshave been applied in different types of rail straightness measurement trollies, respectively. These instrumentswere tested in a high-speed rail section within a certain region of China. The test results were ultimatelyvalidated through using traditional straightedge and feeler gauge methods as reference data to evaluate the railweld joint straightness within the 5-m wavelength range.Findings – The research reveals that IR-method and MCR-method produce reasonably similar measurementresults for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy forwavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed,carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.Originality/value – The research compare two methods’ measurement effects in a longer wavelength rangeand demonstrate the superiority of MCR-method.
文摘The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristics of the operated patients, to determine the main pathologies encountered and to evaluate qualitatively the result of the treatment. In order to improve performance, and the quality of care, and to identify common pathologies in the surgical department, we undertook a retrospective study on surgical activities from January 2009 to December 2010. At the end of this study, out of 474 men and 187 women (equal sex ratio 2.53);we were able to determine the frequency of surgical pathologies. Farmers, housewives and pupils/students were the most represented with 25.9% respectively;20% and 13.3%. The most frequently observed pathologies were wall hernia (44.8%), prostate adenoma (12%) and acute appendicitis (10.5%). The average length of hospitalization was 3.43 days. Infectious complications affected 25 patients (3.8% of cases) and a death rate of 0.45% (i.e. 3 patients). The average cost of care was 53,500 FCFA. Indeed, the reality of surgical practice in health centers was not the same because of the level of skills of practicing surgeons.
文摘Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection.
文摘Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting.
基金China Postdoctoral Science Foundation,Grant/Award Number:2021T140184Program for Science Technology Innovation Talents in Universities of Henan Province,Grant/Award Number:23HASTIT045Scientific Research of Traditional Chinese Medicine Specialized in Henan Province,Grant/Award Number:2022ZY1172。
文摘Background:Acute pancreatitis(AP)is a severe disorder that leads to high morbidity and mortality.Appropriate reference genes are important for gene analysis in AP.This study sought to study the expression stability of several reference genes in the golden Syrian hamster,a model of AP.Methods:AP was induced in golden Syrian hamster by intraperitoneal injection of ethanol(1.35 g/kg)and palmitoleic acid(2 mg/kg).The expression of candidate genes,including Actb,Gapdh,Eef2,Ywhaz,Rps18,Hprt1,Tubb,Rpl13a,Nono,and B2m,in hamster pancreas at different time points(1,3,6,9,and 24 h)posttreatment was analyzed using quantitative polymerase chain reaction.The expression stability of these genes was calculated using Best Keeper,Comprehensive Delta CT,Norm Finder,and ge Norm algorithms and Ref Finder software.Results:Our results show that the expression of these reference genes fluctuated during AP,of which Ywhaz and Gapdh were the most stable genes,whereas Tubb,Eef2,and Actb were the least stable genes.Furthermore,these genes were used to normalize the expression of TNF-αmessenger ribonucleic acid in inflamed pancreas.Conclusions:In conclusion,Ywhaz and Gapdh were suitable reference genes for gene expression analysis in AP induced in Syrian hamster.
基金supported by research grants from the Science and Technology Innovation Program of the Laoshan Laboratory(No.LSKJ202203803)the National Natural Science Foundation of China(No.32273107)+2 种基金supported by the Central Public-Interest Scientific Institution Basal Research Fund,Yellow Sea Fisheries Research Institute,CAFS(No.20603022022001)the project of Putian Science and Technology Department(No.2021NJJ002)the Shinan District Science and Technology Plan Project(No.2022-2-026-ZH).
文摘Quantitative real-time PCR(qRT-PCR)has been widely used for gene expression analysis,and selection of reference genes is a key point to obtain accurate results.To find out optimal reference genes for qRT-PCR in Manila clam Ruditapes philippinarum in response to hypoxia,different tissues were used and compared to evaluate the stability of candidate reference genes under low oxygen stress(DO 0.5mgL^(−1) and DO 2.0mgL^(−1))and normal condition(DO 7.5mgL^(−1)).Seven candidate reference genes were selected to evaluate the stability of their expression levels.The reference genes were evaluated by Delta Ct,BestKeeper,NormFinder and geNorm,and then screened by RefFinder calculation.Under hypoxic stress of 0.5mgL^(−1),the most suitable reference gene for gill and hepatopancreas was RPL31,and the optimal reference genes for axe foot and adductor muscle were TUB and HIS,respectively.For hypoxic stress of 2.0mgL^(−1),the most stable reference gene for gill and hepatopancreas was RPL31,and the optimal reference genes for axe foot and adductor muscle were RPS23 and EF1A,respectively.At the normal condition,HIS and EF1A were identified as the optimal internal reference genes in gill and hepatopancreas respectively,and GFRP2 was the best internal reference gene for axe foot and adductor muscle.The present findings will provide important basis for the selection of reference genes for qRT-PCR analysis of gene expression level in bivalves under hypoxic stress,which might be helpful for the analysis of other molluscs too.
基金Supported by the Natural Science Foundation of Hainan Province (Nos. 320QN212, 2019RC078)the Key Research Project of Hainan Province (No. ZDKJ2019011)
文摘Leopard coral groupers(Plectropomus leopardus),commercially bred in South China,are a significant economical fish species.In this study,by means of quantitative real-time PCR(qRT-PCR)technology,we assessed the stability of six common reference genes expression and selected the appropriate reference genes in leopard coral groupers with or without Vibrio harveyi stimulation at different time points.These data produced by qRT-PCR was handled via the geNorm,NormFinder,and BestKeeper software.The results revealed all the examined reference genes had manifest tissue-specific expression in different tissues.Prior to V.harveyi stimulation,RPL13 gene was the appropriate reference gene among eleven tissue types(blood,spleen,hepatopancreas,kidney,stomach,gill,heart,skin,muscle,intestine,brain)in leopard coral groupers.Under V.harveyi stimulation,the most reliable reference genes varied from tissue to tissue and were closely hinged upon different time points.At 6-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were Actin,B2M,UBCE,and Actin,respectively.At 9-and 12-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were RPL13,Actin,Actin,and Actin,respectively.If one reference gene was preferable,RPL13,Actin,Actin,and Actin could be selected as the reference gene in hepatopancreas,spleen,kidney,and gill of leopard coral groupers after V.harveyi infection,respectively.Expression profiles of two target genes(IL-6 and NK-lysin)were used to further validate reliability of these selected appropriate candidates.This study will lay a solid foundation for the future research on qRTPCR analysis of gene expression in leopard coral groupers.
文摘Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.
基金Supported by the funding for school-level research projects of Yancheng Institute of Technology(No.xjr2019047)the National Natural Science Foundation of China(No.31902362)。
文摘The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected five commonly used housekeeping genes,including β-actin,Elongation factor 1-α(EF1-α),Glyceraldehyde-3-pho sphate dehydrogenase(GAPDH),40S ribosomal protein S18(RPS18),and Tubulin a(TUB-α),then evaluated their expression stability in different adult tissues and under different experimental treatments(salinity stress and Vibrio parahaemolyticus infection).Their expression stability was analyzed by three frequently used programs,geNorm,NormFinder,and BestKeeper.This analysis indicated that multiple genes should be used for normalization,and we concluded that the reference gene combination GAPDH-RPS18-β-actin,should be used for qRT-PCR analysis in different tissues of C.sinensis under normal physiological conditions.For the clams under salinity stress and Vibrio infection,EF1-α-GAPDHRPS18 was recommended as the gene combination for qRT-PCR normalization.TUB-αwas generally poorly ranked by all programs,and should not be used in future studies.This study should provide fundamental support for accurate quantitative gene expression analysis of this species.
文摘Background: Niger is one of the countries that have the highest fertility rate in the world, with 7, 6 children per woman. Zinder is the most populated region of Niger with 5 million inhabitants that is 1/5 of Niger population. The demographic impact that has affected Niger the last 10 years: unemployment poverty and drug use, spawned violence of all kinds in Zinder region (physical and sexual violence). Sexual abuse is a major risk for poor psychiatric and physical outcomes. As sexual violence has serious consequences on the life and future of women and the community and it concerns our field of intervention, we initiated this study whose objective was to determine the socio-epidemiological and lesional aspects, the consequences and appropriate solutions of sexual violence in the Zinder. Methodology: This was a retrospective collection study of all cases of alleged sexual violence received over a 12-year period from 1 January 2009 to 30 June 2021 in Zinder’s referral maternity wards. Results: During the study period, 441 cases of sexual violence were collected;an annual average of 36 cases (441/12). The frequency is 1.29% on the 34,186 consultations. The mean age was 12.31 years with age extremes of 3 to 43 years. Students accounted for 25.39%. Street vendors were found in 224 cases or 50.79%. The predominant reason for admission is rape in 64.63%. The defloration was 52.15%. Pregnancy was found in 118 cases or 26.75%. HIV serology was positive in 1 victim. School dropout was 26.75%. Conclusion: The victims of sexual violence were minors, mostly street vendors and school children. The lack of means of repression at the time allowed the expansion of this violence. The consequences of sexual violence were severe. Advocacy has improved the phenomen on of sexual violence in Zinder.
文摘Natural gas (NG) is one of the most important sources of energy for industrial and domestic consumption in the present era because it is cheap and free from sulfur impurities. Therefore, accurate and precise measurement of its composition is of fundamental importance for trade reasons. To improve the quality of NG gas measurements, certified reference materials (CRMs) should be used for calibration of measuring equipment in order to ensure the traceability of the measurement results to the SI units. For the traceability purpose, a multicomponent natural gas mixture was prepared gravimetrically as a reference material according to ISO 6142 from pure helium, hydrogen, n-pentane, i-pentane, n-butane, i-butane, propane, ethane, hexane, methane and nitrogen. The preparation was done in two dilution steps in 5 L aluminum cylinders. The calculated mole fractions and associated uncertainties of natural gas components were verified by a dual GC-FID/TCD system in accordance with ISO 6143 calibrated by a series of primary gas mixtures (CRMs) produced by an NMI. The results obtained by gravimetry and by GC measurements have been checked for compatibility as required by ISO 6142 and were found in very good agreement. Details of the preparation and calculation of the mole fractions and uncertainties of all gas components are explained in this article.
基金supported by the Sichuan Science and Technology Program under Grant No.2021YFQ0009。
文摘The extraction and understanding of text knowledge become increasingly crucial in the age of big data.One of the current research areas in the field of natural language processing(NLP)is how to accurately understand the text and collect accurate linguistic information because Chinese vocabulary is diverse and ambiguous.This paper mainly studies the candidate entity generation module of the entity link system.The candidate entity generation module constructs an entity reference expansion algorithm to improve the recall rate of candidate entities.In order to improve the efficiency of the connection algorithm of the entire system while ensuring the recall rate of candidate entities,we design a graph model filtering algorithm that fuses shallow semantic information to filter the list of candidate entities,and verify and analyze the efficiency of the algorithm through experiments.By analyzing the related technology of the entity linking algorithm,we study the related technology of candidate entity generation and entity disambiguation,improve the traditional entity linking algorithm,and give an innovative and practical entity linking model.The recall rate exceeds 82%,and the link accuracy rate exceeds 73%.Efficient and accurate entity linking can help machines to better understand text semantics,further promoting the development of NLP and improving the users’knowledge acquisition experience on the text.
基金funded by Jiangsu Agricultural Science and Technology Innovation Fund[CX(20)2030 to J.T.]Qing Lan Project of Jiangsu Province and High-Level Talent Support Program of Yangzhou University.The Key Disciplines of Jiangsu Province.
文摘Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the growth and development of P.lactiflora.Quantitative real-time polymerase chain reaction(qRT-PCR)can evaluate gene expression levels under different stress conditions,and stable internal reference is the key for qRT-PCR.At present,there is no systematic screening of internal reference for correcting gene expressions of P.lactiflora in response to drought stress.In this study,10 candidate genes[ubiquitin(UBQ2),UBQ1,elongation factor 1-α(EF-1α),Histidine(His),eukaryotic initiation factor(eIF),tubulin(TUB),actin(ACT),UBQ3,ACT2,RNA polymerase II(RNA Pol II)]were chosen,and 4 analysis methods were used to compare the stabilities for these 10 genes coping with drought stress.Due to the difference of operation methods,the results of different analysis were distinct,and the final comprehensive analysis indicated that EF-1αwas a relatively stable internal reference gene for P.lactiflora under drought stress.Also,UBQ1 and UBQ2 were the best reference gene combination according to GeNorm analysis.This study will lay a foundation for screening the key genes of P.lactiflora in response to drought stress.
文摘Objectives: The aim of this work was to initially establish both age and weight driven pediatric diagnostic reference levels (DRLs) for chest computed tomography (CT) examinations performed at tertiary care medical institution. Another aim was to compare the presented data with internationally published ones. This initial data shall serve as basis for establishing a national DRLs values for pediatric diagnostic CT examinations. Methods: Dosimetric indexes were collected for the chest examination for 93 patients during the past 2 years in a tertiary care medical city. Results: The results are within and below the international reported levels for chest CT in several countries. Conclusion: Continuous monitoring of the radiation doses received by the patients in computed tomography is continuous and ongoing process in order to ensure compliance and to optimize clinical imaging protocols. More extensive data acquisition and analysis are required to allow better understanding of the contributing factors leading to less patient radiation dose while preserving the clinical image quality. .
文摘This paper proposes an improved exponential curvature-compensated bandgap reference circuit to exploit the exponential relationship between the current gainβof the bipolar junction transistor(BJT)and the temperature as well as reduce the influence of resistance-temperature dependency.Considering the degraded circuit performance caused by the process deviation,the trimmable module of the temperature coefficient(TC)is introduced to improve the circuit stability.The circuit has the advantages of simple structure,high linear stability,high TC accuracy,and trimmable TC.It consumes an area of 0.09 mm^(2)when fabricated by using the 0.25-μm complementary metal-oxide-semiconductor(CMOS)process.The proposed circuit achieves the simulated power supply rejection(PSR)of about-78.7 dB@1 kHz,the measured TC of~4.7 ppm/℃over a wide temperature range from-55℃to 125℃with the 2.5-V single-supply voltage,and the tested line regulation of 0.10 mV/V.Such a high-performance bandgap reference circuit can be widely applied in high-precision and high-reliability electronic systems.
文摘Background: Acute intoxications result from intentionally or accidentally taking a relatively significant amount of a chemical substance which triggers disturbances in the level of psychophysiological functions, the complications of which may lead to mental disorders, physical causalities, and death. Any acute intoxication mostly requires emergency care. Objective: To highlight the prevalence, history, clinical features, emergency treatment, and prediction of acute intoxication cases referred to the emergency services at the Provincial General Reference Hospital in Bukavu, DR-Congo. Methods: A retrospective cross-sectional study was conducted from January 2021 to October 2022 based on an analysis of patients’ medical files. Triage was performed among all-type of patient files recorded in the computerized hospital database Ebale-Sante to sort cases of intoxication. Results: During the observational period, 3966 emergency admissions were counted, of which 321 (8.09%) patients were identified as having acute intoxication. Among these, 100 files that containing sufficient information fit the quality criteria for this study’s analysis. The victims were infants, adolescents and adults aged 1 - 45 years, and 52% were female and 48% were male. Most cases were accidental and, occurred at home, and the victims were driven to the hospital within 2 - 24 hours. The substances consumed included household products, drugs, and herbs. Resuscitation care, antidotes and supportive symptomatic medications ensured that 85% were healed and 10% experienced sequelae;however, 5% died. Conclusion: Acute intoxication occurs in infants mostly accidentally though the ingestion of household products and medicines. Furthermore, suicide cases may occur in traumatized adolescents and discordant couples. People should be informed about how to store hazardous products (e.g.: drugs, household products and pesticides), which should not be available to children, to avoid unintentional poisoning. Special training in clinical toxicology is required to reduce treatment failure.
基金the NSFC has funded 40 research grants for studying the seismic structure beneath continental China, including a grant NSFC42250201 focusing on the CSRM project
文摘The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,called for a seismological reference model to be established in China.The China Seismological Reference Model(CSRM)project was initiated by the National Natural Science Foundation of China with two primary goals:(1)the CSRM would serve as a primary source for the current state of seismological research in China,and(2)the seismic data and constraints used to construct the CSRM would be used as a backbone open-access cyberinfrastructure for future research in seismology.The CSRM project was also intended to promote data exchange and scientific collaboration in seismology in China.Accordingly,two parallel efforts of the project are being pursued:(1)construction of the CSRM,and(2)development of a CSRM product center.The CSRM is jointly constrained by various types of seismic constraints extracted from the seismic data recorded at 4511 seismic stations in continental China following a top-down approach,with the seismic structures in the shallower part of the Earth constrained first.Construction of the CSRM involves three preparation steps:(1)building datasets of various seismic constraints from the seismic data,(2)developing a method to incorporate the constraints of surface wave observations from regional earthquakes into the inversion of the seismic structure,and(3)constructing high-resolution pre-CSRM seismic models of the velocity structure in the shallow crust and the Pn-velocity structure in the uppermost mantle.In the final process,the CSRM will be constructed by jointly inverting all the seismic constraints using the pre-CSRM models as starting models or a priori structures.The CSRM product center(http://chinageorefmodel.org)archives and distributes three types of products:CSRM models,the Level 1 original seismic data used to extract seismic constraints in the construction of the CSRM,and Level 2 data on the seismic constraints derived from the Level 1 data and the inferred earthquake parameters in the construction of the CSRM.The CSRM product center has archived 141 TB of Level 1 data from 1120 permanent broadband stations in the China Seismic Network Center and 3391 temporary stations from various institutions and data centers around the world,as well as 140 GB of Level 2 data on various seismic constraints and inferred event parameters from the construction of the CSRM.The CSRM is expected to provide significant insights into the composition and tectonic dynamics in continental China and to enhance the capability of various seismic hazard mitigation programs in China from near real-time rapid determination of earthquake parameters to an earthquake early warning system.The CSRM could also provide guidance for focuses in future seismological research and the design of future active and passive seismic experiments in China.Several focuses are suggested for future seismological research in China,along with the building of a national cyberinfrastructure to sustain and expand the operations of the CSRM project.
基金This research was supported by the Natural Science Foundation of Inner Mongolia Autonomous Region,China(2022QN04003)the Central Government to Guide Local Scientific and Technological Development(2021ZY0031).
文摘Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the characteristics of drought events.Studying precipitation,reference evapotranspiration(ET_(0)),and vegetation yield can derive information to help conserve water resources in grassland ecosystems in arid and semi-arid regions.In this study,the interactions of precipitation,ET_(0),and vegetation yield in Darhan Muminggan Joint Banner(DMJB),a desert steppe in Inner Mongolia Autonomous Region,China were explored using two-dimensional(2D)and three-dimensional(3D)joint distribution models.Three types of Copula functions were applied to quantitatively analyze the joint distribution probability of different combinations of precipitation,ET_(0),and vegetation yield.For the precipitation–ET_(0)dry–wet type,the 2D joint distribution probability with precipitation≤245.69 mm/a or ET_(0)≥959.20 mm/a in DMJB was approximately 0.60,while the joint distribution probability with precipitation≤245.69 mm/a and ET_(0)≥959.20 mm/a was approximately 0.20.Correspondingly,the joint return period that at least one of the two events(precipitation was dry or ET_(0)was wet)occurred was 2 a,and the co-occurrence return period that both events(precipitation was dry and ET_(0)was wet)occurred was 5 a.Under this condition,the interval between dry and wet events would be short,the water supply and demand were unbalanced,and the water demand of vegetation would not be met.In addition,when precipitation remained stable and ET_(0)increased,the 3D joint distribution probability that vegetation yield would decrease due to water shortage in the precipitation–ET_(0)dry–wet years could reach up to 0.60–0.70.In future work,irrigation activities and water allocation criteria need to be implemented to increase vegetation yield and the safety of water resources in the desert steppe of Inner Mongolia.
