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Somaclonal variations of Soybeans (<i>Glycine Max.</i>L. Merr) stimulated by drought stress based on random amplified polymorphic DNAs (RAPDs) 被引量:8
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作者 Estri Laras Arumingtyas Wahyu Widoretno Serafinah Indriyani 《American Journal of Molecular Biology》 2012年第1期85-91,共7页
In soybeans, drought stress causes 50% yield losses. Breeding for drought tolerance in soybeans has been widely developed using various methods, among which is polyethylene glycol (PEG-6000) induction to simulate drou... In soybeans, drought stress causes 50% yield losses. Breeding for drought tolerance in soybeans has been widely developed using various methods, among which is polyethylene glycol (PEG-6000) induction to simulate drought in vitro. In a previous experiment, three somaclones with different levels of tolerance were generated. The objectives of this research were to determine the RAPD patterns of those somaclones and to investigate the correlation of the RAPD patterns to the drought tolerance characteristics. The results showed eleven RAPD primers capable of amplifying the DNA genome of soybeans, among which four primers were monomorphic and seven were polymorphic. Two of the polymorphic primers, OPK7 and OPK12, are capable of differentiating medium tolerance traits from other traits. Bands that are specific for medium tolerance against drought were 450 bp and 650 bp in size, generated by the OPK7 primer, and the band of 2000 bp, generated by the OPK12 primer. However, there was no band capable of differentiating between sensitive and tolerance varieties/lines, although some changing of the DNA sequence was detected in this research. This indicates that there are other factors responsible for the expression of drought tolerance. 展开更多
关键词 RAPD Drought Tolerance SOYBEANS Somaclones
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Study on Somaclonal Variation of Spring Wheat
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作者 JIANGShu-mei HUShang-lian LIWen-xiong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期1-9,共9页
Somaclonal variation of calli and regenerated plants of spring wheat were detected by using technique RAPD in the study. Calli at different culture stages and regenerated plants derived from young spikes and immature ... Somaclonal variation of calli and regenerated plants of spring wheat were detected by using technique RAPD in the study. Calli at different culture stages and regenerated plants derived from young spikes and immature embryos were used as materials. Molecular variation could be reflected from electrophoresis pattern of RAPD fragments at different culture stage in calli, and in regenerated plants derived from different explants, even no phenotype variations were found. Somaclonal variation in calli and in regenerated plants appeared regularly: A higher frequency of variation in hybrids F2 was detected than that of the cultivar that is stable genetically. High variation frequency of RAPD fragments appeared in calli when cultured 75 days. The identical variations of RAPD fragments were observed in calli and in the regenerated plants induced from different genotype or explants. The variation frequency detected is higher in regenerated plants than that of in calli. RAPD could be applied easily and simply to determine variation in level of DNA at each stage cultured in vitro. 展开更多
关键词 spring wheat somaclonal variation CALLUS regenerated plant RAPD
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Micropropagation of Daylily(Hemerocallis fulva)from Crown-Tip Explants and Assessment of Somaclonal Variation of in Vitro-Propagated Plants Using SCoT Markers
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作者 Esraa E.Shalan Said S.Soliman +6 位作者 Ahmed A.Mahmoud Jameel M.Al-Khayri Salha M.ALshamrani Fatmah A.Safhi Areej S.Jalal Diaa Abd El-Moneim Abdallah A.Hassanin 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第7期2183-2196,共14页
Determination of the somaclonal variation of in vitro-propagated plants is crucial to determine the appropriate micropropagation protocol and growth regulators for commercial scale multiplication.In this research,nine... Determination of the somaclonal variation of in vitro-propagated plants is crucial to determine the appropriate micropropagation protocol and growth regulators for commercial scale multiplication.In this research,nine multiplication media(MM)augmented with different concentrations of 6-benzyl adenine(BA),Kinetin(Kin),and Thidiazuron(TDZ),Three rooting media(RM)supplemented with three levels ofα-naphthalene acetic acid(NAA)and three types of soil mixtures(v/v);Coco peat/Vermiculite/Sand(CVS),Peat moss/Perlite/Sand(PPS)and Peat moss/Perlite(PP)were used in the micropropagation protocol of daylily plants.MM2 showed the maximum shoot length and the number of leaves,while MM9 showed the maximum number of shoots.The RM1 showed the maximum root length and the number of roots.During acclimatization,CVS,PPS,and PP soil mixture showed similar performance except the CVS mixture showed lower performance regarding plant height and diameter.The genetic fidelity of micropropagated plants was evaluated using Start Codon Targeted(SCoT)Markers.Six SCoT primers amplified 51 scorable bands with an approximate range from 146 bp to 1598 bp size.Thirty one out of 51 loci were presented in the mother plants.40 loci were polymorphic,11 were monomorphic and 7 were unique.The amplification patterns of the micropropagated plants demonstrated genetic integrity to the mother plant ranging from 84.32 to 47.06 and somaclonal variations ranging from 52.94 with 5 mg/l BA pathway to 15.68 with 1mg/l TDZ pathway,thus demonstrating that the homogeneity and the variation of the micropropagated plants affected by the type and the quantity of the plant growth regulator used during multiplication subcultures.This research can be successfully used for other ornamental and medicinal plants’bulk multiplication,germplasm conservation,and future genetic improvement. 展开更多
关键词 Genetic fidelity medicinal plants MICROPROPAGATION molecular markers ornamental plants somaclonal variation
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Somaclonal variations as a mean for obtaining regenerants with different growth rates in poplar (<i>Populus ×berolinensis</i>Dipp.)
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作者 Kim Z. Gamburg Viktor K. Voinikov 《Natural Science》 2013年第5期599-607,共9页
Adventive regenerants of Populus × berolinensis Dipp. were obtained on 1/2 MS salts with sucrose, vitamins, BA, TDZ and NAA using stem, petiole and leaf explants. They differed from each other in plantlet dimensi... Adventive regenerants of Populus × berolinensis Dipp. were obtained on 1/2 MS salts with sucrose, vitamins, BA, TDZ and NAA using stem, petiole and leaf explants. They differed from each other in plantlet dimensions. More than 50 clones were produced from initial regenerants by excision and rooting of apexes and lateral shoots. Differences in stem length and thickness were observed between 200 field plants produced from in vitro plantlets. Differences in stem length were conditioned mainly due to different number of internodes and not by internodes’ lengths. Plants grown from cuttings excised from highest and smallest plants retained the abilities of mother plants to grow with different rates. It is concluded that somaclonal variability can be used for selection of fast growing poplar plants which are necessary for industrial plantations. These plants can be used for this purpose without the limitations existing for transgenic plants. 展开更多
关键词 somaclonal variations Adventive Regenerants POPLAR POPULUS x Berolinensis Dipp. Propagation in VITRO Fast GROWING Plants
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Study on Somaclonal Variation through a Callus Regeneration System in Betula Platyphylla
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作者 Y.G. Zhan  A.P. Hao  F.H. Qi 《分子植物育种》 CAS CSCD 2007年第2期293-293,共1页
Calli have been widely used as research materials for clonal propagation and transformation of trees owing to their high multiplication rates and capacity of large-scale propagation. Till now, very little is known on ... Calli have been widely used as research materials for clonal propagation and transformation of trees owing to their high multiplication rates and capacity of large-scale propagation. Till now, very little is known on the soma- 展开更多
关键词 植物伤口 愈合组织 再生系统 桦树
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The Application of Somaclonal Variation in Early Maturity,High Yield and High Quality Improvement in Wheat 被引量:2
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作者 Hu Shanglian, Zeng Hanbing, Li Wenxiong(Wheat Physiol. and Biotech. Lab, Dept. of Agronomy, NEAU, Harbin 150030, PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1996年第2期81-87,共7页
Yield characters, maturity and grain protein content of somaclones derived both from immature embryo of cultivar 77(2)-Spring and single-cell culture of cultivar NE7742 in vitro were studied and the wide variation was... Yield characters, maturity and grain protein content of somaclones derived both from immature embryo of cultivar 77(2)-Spring and single-cell culture of cultivar NE7742 in vitro were studied and the wide variation was found. Somaclones with maturity 8 days earlier than or the same as CK NE 7742 (high yield, early maturity and high quality), combining with high quality (grain protein content 15.5% - 18%) and high yield (the same as 7724 or higher) have been found and selected and now multiplied for 8 generations. The results of cultivar comparison trial in 1995 showed that several somaclones (the yields were significantly higher than CK DN120) could be used directly in wheat production. The studies confirmed that somaclonal variation is one of the effective ways for early maturity, high-yielding and high-quality improvement in wheat. 展开更多
关键词 common wheat (Triticum aestivum L) immature embryo culture single cell culture in vitro somaclonal variation
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Associations of genome-wide structural variations with phenotypic differences in cross-bred Eurasian pigs 被引量:1
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作者 Wencheng Zong Jinbu Wang +8 位作者 Runze Zhao Naiqi Niu Yanfang Su Ziping Hu Xin Liu Xinhua Hou Ligang Wang Lixian Wang Longchao Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期68-87,共20页
Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability ... Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds. 展开更多
关键词 Body size GWAS PIG SKELETON Structural variations
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Insights into genetic diversity and phenotypic variations in domestic geese through comprehensive population and pan-genome analysis 被引量:1
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作者 Guangliang Gao Hongmei Zhang +5 位作者 Jiangping Ni Xianzhi Zhao Keshan Zhang Jian Wang Xiangdong Kong Qigui Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期88-107,共20页
Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and ... Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and other phenotypic traits.Constructing a pan-genome facilitates a thorough identification of genetic variations,thereby deepening our comprehension of the molecular mechanisms underlying genetic diversity and phenotypic variability.Results To comprehensively facilitate population genomic and pan-genomic analyses in geese,we embarked on the task of 659 geese whole genome resequencing data and compiling a database of 155 RNA-seq samples.By constructing the pan-genome for geese,we generated non-reference contigs totaling 612 Mb,unveiling a collection of 2,813 novel genes and pinpointing 15,567 core genes,1,324 softcore genes,2,734 shell genes,and 878 cloud genes in goose genomes.Furthermore,we detected an 81.97 Mb genomic region showing signs of genome selection,encompassing the TGFBR2 gene correlated with variations in body weight among geese.Genome-wide association studies utilizing single nucleotide polymorphisms(SNPs)and presence-absence variation revealed significant genomic associations with various goose meat quality,reproductive,and body composition traits.For instance,a gene encoding the SVEP1 protein was linked to carcass oblique length,and a distinct gene-CDS haplotype of the SVEP1 gene exhibited an association with carcass oblique length.Notably,the pan-genome analysis revealed enrichment of variable genes in the“hair follicle maturation”Gene Ontology term,potentially linked to the selection of feather-related traits in geese.A gene presence-absence variation analysis suggested a reduced frequency of genes associated with“regulation of heart contraction”in domesticated geese compared to their wild counterparts.Our study provided novel insights into gene expression features and functions by integrating gene expression patterns across multiple organs and tissues in geese and analyzing population variation.Conclusion This accomplishment originates from the discernment of a multitude of selection signals and candidate genes associated with a wide array of traits,thereby markedly enhancing our understanding of the processes underlying domestication and breeding in geese.Moreover,assembling the pan-genome for geese has yielded a comprehensive apprehension of the goose genome,establishing it as an indispensable asset poised to offer innovative viewpoints and make substantial contributions to future geese breeding initiatives. 展开更多
关键词 Gene-CDS haplotype Goose GWAS PAN-GENOME Presence-absence variation Selection signal
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Origin of the presence/absence variation of the LTIA1/LTIA2 mini-ribonucleaseⅢgenes required for low-temperature growth in rice 被引量:1
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作者 Jing Yang Yu Peng +5 位作者 Limin Mi Aiqing Sun Ping Li Yan Wang Yi Zhang Sheng Teng 《The Crop Journal》 SCIE CSCD 2024年第5期1459-1470,共12页
A rice low temperature-induced albino variant was determined by the recessive ltia1 and ltia2 genes.LTIA1 and LTIA2 encode highly conserved mini-ribonucleasesⅢlocated in chloroplasts and expressed in aerial parts of ... A rice low temperature-induced albino variant was determined by the recessive ltia1 and ltia2 genes.LTIA1 and LTIA2 encode highly conserved mini-ribonucleasesⅢlocated in chloroplasts and expressed in aerial parts of the plant.At low temperature,LTIA1 and LTIA2 redundantly affect chlorophyll levels,non-photochemical quenching,photosynthetic quantum yield of PSⅡand seedling growth.LTIA1 and LTIA2 proteins are involved in splicing of atp F and the biogenesis of 16S and 23S rRNA in chloroplasts.Presence/absence variation of LTIA1,the ancestral copy,was found only in japonica but that of LTIA2 in all rice subgroups.Accessions with LTIA2 presence tended to be distributed more remote from the equator compared to those with LTIA2 absence.LTIA2 duplicated from LTIA1 at the early stage of divergence of the AA genome Oryza species but deleted againin O.nivara.In cultivated rice,absence of LTIA2 is derived from O.nivara.LTIA1 absence occurred more recently in japonica. 展开更多
关键词 RICE Low temperature induced albino Mini-RNaseⅢ Presence/Absence variations Evolution
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Spatial Variation in CO_(2) Concentration Improves the Simulated Surface Air Temperature Increase in the Northern Hemisphere 被引量:1
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作者 Jing PENG Li DAN Xiba TANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1614-1628,1676-1685,共25页
The increasing concentration of atmospheric CO_(2) since the Industrial Revolution has affected surface air temperature.However,the impact of the spatial distribution of atmospheric CO_(2) concentration on surface air... The increasing concentration of atmospheric CO_(2) since the Industrial Revolution has affected surface air temperature.However,the impact of the spatial distribution of atmospheric CO_(2) concentration on surface air temperature biases remains highly unclear.By incorporating the spatial distribution of satellite-derived atmospheric CO_(2) concentration in the Beijing Normal University Earth System Model,this study investigated the increase in surface air temperature since the Industrial Revolution in the Northern Hemisphere(NH) under historical conditions from 1976-2005.In comparison with the increase in surface temperature simulated using a uniform distribution of CO_(2),simulation with a nonuniform distribution of CO_(2)produced better agreement with the Climatic Research Unit(CRU) data in the NH under the historical condition relative to the baseline over the period 1901-30.Hemispheric June-July-August(JJA) surface air temperature increased by 1.28℃ ±0.29℃ in simulations with a uniform distribution of CO_(2),by 1.00℃±0.24℃ in simulations with a non-uniform distribution of CO_(2),and by 0.24℃ in the CRU data.The decrease in downward shortwave radiation in the non-uniform CO_(2) simulation was primarily attributable to reduced warming in Eurasia,combined with feedbacks resulting from increased leaf area index(LAI) and latent heat fluxes.These effects were more pronounced in the non-uniform CO_(2)simulation compared to the uniform CO_(2) simulation.Results indicate that consideration of the spatial distribution of CO_(2)concentration can reduce the overestimated increase in surface air temperature simulated by Earth system models. 展开更多
关键词 spatial variations of CO_(2) surface air temperature Earth system model land surface albedo leaf area index
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Variations in evaporation from water surfaces along the margins of the Badain Jaran Desert over nearly 60 years and influencing factors 被引量:1
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作者 Li-juan Wang Zhe Wang +3 位作者 Gao-lei Jiang Zhen-long Nie Jian-mei Shen Sheng-hua Song 《Journal of Groundwater Science and Engineering》 2024年第3期253-263,共11页
Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evapor... Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evaporation from water surfaces and identified the dominant controlling factors.Methods used included linear trend analysis,linear tendency estimation,the departure method,the rank correlation coefficient-based method,and Multiple Linear Regression(MLR).Results indicate notable spatiotemporal differences in evaporation distribution and evolution.Spatially,average annual evaporation exhibited a pronounced altitude effect,decreasing at a rate of about 8.23 mm/m from east to west with increasing altitude.Temporally,annual evaporation showed significant upward trends after 1996 at the northeastern(Guaizi Lake)and western(Dingxin)margins,with rates of 132 mm/10a and 105 mm/10a,respectively.Conversely,along the northwestern(Ejina Banner)and southern(Alxa Right Banner)margins of the desert,an evaporation paradox was observed,with annual evaporation trending downward at rates of 162 mm/10a and 187 mm/10a,respectively,especially after 1987.The dominant factors controlling evaporation varied spatially:Average annual temperature and relative humidity influended the western margin(Dingxin),average annual temperature was the key factor for the northeastern margin(Guaizi Lake),and average wind speed was crucial for the northern(Ejina Banner)and southern(Alxa Right Banner)margins. 展开更多
关键词 Evaporation from water surface Evaporation paradox Dominant controlling factor variation trend
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A new two-step variational model for multiplicative noise removal with applications to texture images
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作者 ZHANG Long-hui YAO Wen-juan +2 位作者 SHI Sheng-zhu GUO Zhi-chang ZHANG Da-zhi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期486-501,共16页
Multiplicative noise removal problems have attracted much attention in recent years.Unlike additive noise,multiplicative noise destroys almost all information of the original image,especially for texture images.Motiva... Multiplicative noise removal problems have attracted much attention in recent years.Unlike additive noise,multiplicative noise destroys almost all information of the original image,especially for texture images.Motivated by the TV-Stokes model,we propose a new two-step variational model to denoise the texture images corrupted by multiplicative noise with a good geometry explanation in this paper.In the first step,we convert the multiplicative denoising problem into an additive one by the logarithm transform and propagate the isophote directions in the tangential field smoothing.Once the isophote directions are constructed,an image is restored to fit the constructed directions in the second step.The existence and uniqueness of the solution to the variational problems are proved.In these two steps,we use the gradient descent method and construct finite difference schemes to solve the problems.Especially,the augmented Lagrangian method and the fast Fourier transform are adopted to accelerate the calculation.Experimental results show that the proposed model can remove the multiplicative noise efficiently and protect the texture well. 展开更多
关键词 multiplicative noise removal texture images total variation two-step variational method aug-mented Lagrangian method
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Development of the A&GBE base editor for efficiently generating abundant genetic variation in rice
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作者 Wenhui Zhang Yaqi Xu +5 位作者 Jingxuan Cui Yingshuang Xue Lijie Zhang Wenjuan Wu Chong Wang Hui Zhang 《The Crop Journal》 SCIE CSCD 2024年第6期1801-1805,共5页
We have developed a dual base editor,rA&GBE,by fusing adenine and glycosylase base editors.It can induce up to eight types of mutations in T0-generation rice,including single-base conversion,simultaneous multiple-... We have developed a dual base editor,rA&GBE,by fusing adenine and glycosylase base editors.It can induce up to eight types of mutations in T0-generation rice,including single-base conversion,simultaneous multiple-base conversions,and InDels,using a single guide RNA.A-to-G and C-to-G/T conversions occur simultaneously on the same DNA strand.The rA&GBE system may prove useful for crop improvement and in planta direct evolution. 展开更多
关键词 CRISPR A&GBE Genetic variation RICE
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A Study to Observe Pulse Pressure Variation after Induction with Propofol for General Anesthesia
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作者 Kunal Tewari Vibhu Raghuvanshi +3 位作者 Deepak Mishra Nitin Pahuja Maj Jyotsna Om Bahadur Thapa 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期343-350,共8页
Background and Aims: Pulse pressure variation (PPV) is a reliable and predictive dynamic parameter presently being utilized for fluid responsiveness. In the operating room, fluid administration based on PPV monitoring... Background and Aims: Pulse pressure variation (PPV) is a reliable and predictive dynamic parameter presently being utilized for fluid responsiveness. In the operating room, fluid administration based on PPV monitoring helps the physician in deciding whether to volume resuscitate or use interventions in patients undergoing surgery. Propofol is an intravenous induction agent which lowers blood pressure. There are multiple causes such as depression in cardiac output, and peripheral vasodilatation for hypotension. We undertook this study to observe the utility of PPV as a guide to fluid therapy after propofol induction. Primary outcome of our study was to monitor PPV as a marker of fluid responsiveness for the hypotension caused by propofol induction. Secondary outcome included the correlation of PPV with other hemodynamic parameters like heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP);after induction with propofol at regular interval of time. Methods: A total number of 90 patients were recruited. Either of the radial artery was then cannulated under local anaesthesia with 20G VygonLeadercath arterial cannula and invasive monitoring transduced. A baseline recording of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and PPV was then recorded. Patients were then induced with predetermined doses of propofol (2 mg/kg) and recordings of HR, SBP, DBP, and PPV were taken at 5, 10 and 15 minutes. Results: Intraoperatively, PPV was significantly higher at 5 minutes and significantly lower at 15 minutes after induction. It was observed that there were no statistically significant correlations between PPV and SBP or DBP. PPV was strongly and directly associated with HR. Conclusion: We were able to establish that PPV predicts fluid responsiveness in hypotension caused by propofol induction;and can be used to administer fluid therapy in managing such hypotension. However, PPV was not directly correlated with hypotension subsequent to propofol administration. 展开更多
关键词 Pulse Pressure variation (PPV) PROPOFOL Fluid Responsiveness
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Small temporal variation in abundance of virioplankton compared to bacterioplankton and phytoplankton in two bays in the northern South China Sea
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作者 Jiandong ZHANG Yineng LI +1 位作者 Lijuan LONG Sijun HUANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1130-1142,共13页
Variations of picoplankton groups were investigated over a one-month period in Daya Bay and Sanya Bay,in the northern South China Sea.The two coastal regions exhibited different variation patterns in physicochemical p... Variations of picoplankton groups were investigated over a one-month period in Daya Bay and Sanya Bay,in the northern South China Sea.The two coastal regions exhibited different variation patterns in physicochemical parameters.Moreover,the diel variations of picoplankton groups were different between the two bays.The abundance of the picoplankton in Sanya Bay displayed a pronounced diel variation,while it was not significant in Daya Bay.In addition,some similar patterns of picoplankton abundance were discovered.In the two bays,virioplankton exhibited the smallest fluctuation range,whereas picocyanobacteria fluctuated most markedly.The fluctuation range of picoplankton groups was larger in spring tide than in neap tide,especially in Sanya Bay.Random forest model analysis demonstrated that the variation of picoplankton groups was attributed to physical and chemical factors in Sanya Bay and Daya Bay,respectively.Therefore,our findings suggest that virioplankton abundance can persist more stably in response to changing environmental conditions compared to bacterioplankton and picophytoplankton. 展开更多
关键词 diel variation ABUNDANCE picoplankton group VIRIOPLANKTON PICOCYANOBACTERIA
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Temperature is a cryptic factor shaping the geographical pattern of genetic variation in Ceratophyllum demersum across a subtropical freshwater lake
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作者 Yixian Li Xuyao Zhao +2 位作者 Manli Xia Xinzeng Wei Hongwei Hou 《Plant Diversity》 SCIE CAS CSCD 2024年第5期630-639,共10页
Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic stressors.Environmental... Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic stressors.Environmental factors are thought to be important drivers shaping the genetic and epigenetic variation of aquatic plants.However,the links among genetic diversity,epigenetic variation,and environmental variables remain largely unclear,especially for clonal aquatic plants.Here,we performed population genetic and epigenetic analyses in conjunction with habitat discrimination to elucidate the environmental factors driving intraspecies genetic and epigenetic variation in hornwort(Ceratophyllum demersum)in a subtropical lake.Environmental factors were highly correlated with the genetic and epigenetic variation of C.demersum,with temperature being a key driver of the genetic variation.Lower temperature was detected to be correlated with greater genetic and epigenetic variation.Genetic and epigenetic variation were positively driven by water temperature,but were negatively affected by ambient air temperature.These findings indicate that the genetic and epigenetic variation of this clonal aquatic herb is not related to the geographic feature but is instead driven by environmental conditions,and demonstrate the effects of temperature on local genetic and epigenetic variation in aquatic systems. 展开更多
关键词 Genetic diversity Epigenetic variation TEMPERATURE MACROPHYTE Restoration
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The Variation of Plankton Community Structure in Artificial Reef Area and Adjacent Waters in Haizhou Bay
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作者 GAO Shike SHI Yixi +1 位作者 LU Yanan ZHANG Shuo 《Journal of Ocean University of China》 CAS CSCD 2024年第1期264-276,共13页
Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among MPAs.According to the survey from MPAs dominated by ar... Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among MPAs.According to the survey from MPAs dominated by artificial reefs and adjacent waters(estuary area(EA),aquaculture area(AA),artificial reef area(ARA),natural area(NA)and comprehensive effect area(CEA))in Haizhou Bay in spring and autumn,we analyzed phyto-zooplankton composition,abundance and biomass,and correlation with hydrologic variables to gain information about the forces that structure the plankton.The results showed that the dominant zooplankton were copepods(spring,98.9%;autumn,94.2%),while the phytoplankton were mainly composed of Bacillariophyta(spring,61.8%;autumn,95.6%).The RDA results showed that temperature,salinity and depth highly associated with the distribution and composition of plankton species among the habitats than other factors in spring;temperature,Chla and DO had the strongest influence in autumn.The zooplankton in the ARA and AA ecosystems basically contained the same species as those in other habitats,and each habitat also exhibited a relatively unique combination of plankton species.The structures of the EA zooplankton in spring and the EA phytoplankton in both seasons were much different than other habitats,which may have been caused by factors such as currents and tides.We concluded that there exists similarity of the plankton community between artificial reef area and adjacent waters,whereas the EAs may be relatively independent systems.Therefore,these interaction between plankton community should be considered when designing MPA networks,and ocean circulations should be considered more than the environmental factors. 展开更多
关键词 ZOOPLANKTON PHYTOPLANKTON seasonal variation environmental factor artificial reef
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Seasonal Variation of Hearing Sensitivity in the Red-eared Slider(Trachemys scripta elegans)
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作者 Tongliang WANG Jinxia YANG +3 位作者 Handong LI Jinhong LEI Haitao SHI Jichao WANG 《Asian Herpetological Research》 SCIE CSCD 2024年第2期82-89,共8页
Seasonal variation of hearing sensitivity has been observed in many vertebrate groups with obvious vocal behaviors.Circulating hormones,conspecific calling signals,and temperature are potential factors that drive thes... Seasonal variation of hearing sensitivity has been observed in many vertebrate groups with obvious vocal behaviors.Circulating hormones,conspecific calling signals,and temperature are potential factors that drive these plasticity patterns.Turtles have a hearing range that appears to be limited to under 1.5 kHz and are often thought to be non-vocal;thus,they are commonly neglected in vocal communication research.In this study,we aimed to determine whether the auditory phenotype exhibits seasonal variation in sensitivity and to analyze the potential factors driving such variation patterns in turtles.We measured hearing sensitivity and sex hormone levels in female(estradiol)and male(testosterone and dihydrotestosterone)Red-eared sliders(Trachemys scripta elegans)during spring and winter.The results showed that auditory brainstem response(ABR)thresholds were significantly lower in spring than in winter at a frequency range of 0.5-0.9 kHz.The hearing-sensitivity bandwidth was wider,and the ABR latency was significantly shorter in spring than in winter.No significant differences were found in estradiol,testosterone,and dihydrotestosterone levels in T.scripta elegans between spring and winter.This study is the first to reveal the seasonal variation of peripheral hearing sensitivity in turtles,a special animal group with limited hearing range and less vocalization.Temperature variations may be used to explain these seasonal effects,but further research is required to confirm our findings. 展开更多
关键词 auditory plasticity seasonal variation TEMPERATURE TURTLES
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Radio-Anatomical Variations of Both Origin and Foraminal Entrance of Vertebral Arteries in Black African Human: Experience from Côte d’Ivoire
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作者 Ousmane Toumany Cherif Haidara Thiam Sokhna Astou Gawane +6 位作者 Kemesso Boubacar Sanogo Maïmouna Kanté Abdoulaye Magaye Gaye Ongoïba Nouhoum Zunon-Kipré Yvan Kakou Konan Médard 《Forensic Medicine and Anatomy Research》 2024年第3期27-39,共13页
The vertebral arteries (VAs) are a system of two blood vessels through which blood is transported to the posterior cerebral fossa. VAs may emerge at different sides from the aortic ostium. The aim of our study was to ... The vertebral arteries (VAs) are a system of two blood vessels through which blood is transported to the posterior cerebral fossa. VAs may emerge at different sides from the aortic ostium. The aim of our study was to establish a reference of radio-anatomical variations of the VAs in black African human from Côte d’Ivoire experience. Materials and Methods: Forty patients underwent Computed Angio-Tomography (CAT) of the supra-aortic vessels (SAoVs). Included in our study were patients who underwent CAT of the SAoV from January 2019 to December 2021, those excluded in our study as Caucasians and other leucoderma humans. This exclusion allowed for highlighting only black humans VAs variations. The variations of both origins and foraminal entrance of VA were assessed. We carried out a model of univariate regression for assessing the occurrence of VA variations related to demographic included mainly age, gender and clinical features. Results: The average age was 48 ± 12 years with 0.66 of sex ratio. The most frequent indication for carrying out CAT was brain ischemic stroke assessment (25%). The atypical origin of the VAs out of subclavian arteries (SCA) was 25%. Origin from the aortic arch (AoA) was 17.5%. Six (15%) were unilateral while one (2.5%) was bilateral variation from a common trunk as pattern. Bilateral sixth cervical foramina inlet was 85%. Female sex and ischemic stroke assessment had a statistically significant correlation. Conclusion: VAs variations studies in black African human are lacking in the literature. Our findings depicted a considerable amount of VAs variations opening the field for further observational studies in black African human. 展开更多
关键词 Vertebral Artery variationS Morphology VESSELS Supra-Aortic Back African
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A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area
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作者 H.N.Sowmya M.Dinamani +4 位作者 G.P.Shivashankara H.K.Ramaraju B.S.Surendra Vijaya V.Shanbhag R.Prajwal 《Research in Cold and Arid Regions》 CSCD 2024年第1期14-19,共6页
In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was c... In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. Hourly sample data was collected using a BTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 a.m.to 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. However, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions. 展开更多
关键词 BTEX Summer variation Meteorological parameters Correlation
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