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2.
Breed Sci ; 73(2): 193-203, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37404343

RESUMO

A unique genetic variation with respect to blast resistance was clarified in 201 rice accessions from Vietnam. These accessions were classified into three clusters-A, B1, and B2-based on their reactions to 26 standard differential blast isolates selected in Vietnam. Cluster A was the dominant cultivar group in Vietnam and the most susceptible of the three clusters. Cluster B1 was the smallest group and the most resistant. Cluster B2 was the second-most dominant group and of intermediate resistance between clusters A and B1. The percentages of accessions comprising each cluster varied by region and area. Accessions in cluster A were distributed widely throughout Vietnam and had the highest frequencies in both the Central and North regions. Accessions in cluster B2 were found with highest frequencies in the mountainous and intermediate areas of the North region. Accessions in cluster B1 were found with highest frequencies in the Central region and Red River Delta area (North region). These results suggest that rice accessions in Vietnam were basically susceptible (cluster A) or of intermediate resistance (cluster B2), and that high-resistance cultivars were mainly distributed in the low altitude areas, such as the Red River Delta area and Central region.

3.
J Dairy Sci ; 106(2): 1159-1167, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460505

RESUMO

Interbull's multiple across-country evaluaftion provides national breeding organizations with breeding values for internationally used bulls, which integrate performance data obtained in different breeding populations, environments, and production systems. However, breeding value-based selection decisions on domestic individuals born to foreign sires can only benefit from Interbull breeding values if they are integrated such that their information can contribute to the breeding values of all related domestic animals. For that purpose, several methods have been proposed which either model Interbull breeding values as prior information in a Bayesian approach, as additional pseudo data points, or as correlated traits, where these methods also differ in their software and parameterization requirements. Further, the complexity of integration also depends on the traits and genetic evaluation models. Especially random regression models require attention because of the dimensionality discrepancy between the number of Interbull breeding values and the number of modeled genetic effects. This paper presents the results from integrating 16,063 Interbull breeding values into the domestic single-step random regression test-day model for milk, fat, and protein yield for Australian Red dairy cattle breeds. Interbull breeding values were modeled as pseudo data points with data point-specific residual variances derived within animal across traits, ignoring relationships between integrated animals. Results suggest that the integration was successful with regard to alignment of Interbull breeding values with their domestic equivalent as well as with regard to the individual and population-wide increase in reliabilities. Depending on the relationship structure between integration candidates, further work is required to account for those relationships in a computationally feasible manner. Other traits with separate parity effects nationally could use a similar approach, even if not modeled with a test-day model.


Assuntos
Lactação , Leite , Animais , Bovinos/genética , Masculino , Feminino , Teorema de Bayes , Austrália , Fenótipo , Leite/química , Lactação/genética , Modelos Genéticos
4.
S Afr J Commun Disord ; 69(2): e1-e6, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36073076

RESUMO

BACKGROUND:  Vietnam's first speech and language therapy (SLT) degrees commenced in 2019 utilising international educators. Continuity of the degrees was impacted by travel restrictions during the coronavirus disease 2019 (COVID-19) pandemic. OBJECTIVES:  This article presents a descriptive case report exploring the viability of online learning to continue clinical education (CE) of SLT students in Vietnam during the pandemic. METHOD:  Students were scheduled for face to face placements throughout 2021. International SLT educators were to travel to Vietnam and work with interpreters and locally trained certificate level therapists to provide placement supervision. When travel became impossible, tele-supervision by international therapists working remotely and in partnership with local therapists and interpreters was arranged. The second wave of Covid-19 excluded students from healthcare settings early in their placements. To conclude these placements, tele-supervisors led online case-based discussions with students. For subsequent placements, Vietnamese and international therapists facilitated two to three weeks of online case-based group discussions for students, using cases with videos or avatars. RESULTS:  Learning outcomes for students, as evidenced in written and oral assessments demonstrated attainment of many of the learning objectives of the placements. Satisfaction for all participants (students, tele-supervisors, online group facilitators) was high. Students will undertake face to face placements in the future; however they will commence these placements with heightened clinical reasoning and planning skills. CONCLUSION:  Online CE is possible in LMIC and, as part of a program which includes face to face placements, can support essential CE outcomes and enhance preparation for subsequent direct experiences with patients.


Assuntos
COVID-19 , Educação a Distância , Humanos , Terapia da Linguagem , Pandemias , Fala , Vietnã
5.
Infect Drug Resist ; 15: 4575-4583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003989

RESUMO

Purpose: The purpose of this study was to characterize the population-based pharmacokinetic (POP-PK) profile of imipenem in Vietnamese adult patients and to assess the probability of target attainment (PTA) of the pharmacokinetic/pharmacodynamic (PK/PD) parameter to determine the optimal dose. Patients and Methods: A POP-PK model of imipenem was developed in patients with severe infection from a 1500-bed general hospital in Vietnam, using MONOLIX 2019. After the initial dose infusion, 6 blood samples per patient were collected to measure plasma imipenem levels. Eight covariates (eg, age, weight) were investigated to ascertain their influence on imipenem's PK. Monte Carlo simulations were performed to determine the PTA for the time in which the total steady-state imipenem concentrations remained above the MIC (T>MIC) for 40% and 100% of the dosing interval. Results: The best fit to the PK data was a two-compartment model with inter-individual variability (IIV) in clearance (CL), central volume of distribution (Vc), intercompartmental clearance (Q), and peripheral volume of distribution (Vp). Only creatinine clearance was retained as a covariate on CL in the final model. The typical value of CL and Vc were estimated to be 4.79 L/h and 11.1 L, respectively. The between-subject variability in this population was noted to be high (>38%, especially for IIV on Q at 110%). Prolonged or continuous infusion demonstrated efficacy (40% T>MIC) against bacteria with a MIC of 4mg/L. To achieve 100% T>MIC or bacteria with MIC>4 mg/L, however, the number of doses must be increased while maintaining the same daily dose for the 3-hour prolonged infusion regimen. Conclusion: A population pharmacokinetic model of imipenem was developed for Vietnamese adult patients with severe illness. By using Monte Carlo simulation, the appropriate dose has been suggested based on the bacterial MIC value and the targeted PK/PD goal.

6.
J Dairy Sci ; 100(9): 7362-7367, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28711268

RESUMO

Excessive ambient temperature and humidity can impair milk production and fertility of dairy cows. Selection for heat-tolerant animals is one possible option to mitigate the effects of heat stress. To enable selection for this trait, we describe the development of a heat tolerance breeding value for Australian dairy cattle. We estimated the direct genomic values of decline in milk, fat, and protein yield per unit increase of temperature-humidity index (THI) using 46,726 single nucleotide polymorphisms and a reference population of 2,236 sires and 11,853 cows for Holsteins and 506 sires and 4,268 cows for Jerseys. This new direct genomic value is the Australian genomic breeding value for heat tolerance (HT ABVg). The components of the HT ABVg are the decline in milk, fat, and protein per unit increase in THI when THI increases above the threshold of 60. These components are weighted by their respective economic values, assumed to be equivalent to the weights applied to milk, fat, and protein yield in the Australian selection indices. Within each breed, the HT ABVg is then standardized to have a mean of 100 and standard deviation (SD) of 5, which is consistent with the presentation of breeding values for many other traits in Australia. The HT ABVg ranged from -4 to +3 SD in Holsteins and -3 to +4 SD in Jerseys. The mean reliabilities of HT ABVg among validation sires, calculated from the prediction error variance and additive genetic variance, were 38% in both breeds. The range in ABVg and their reliability suggests that HT can be improved using genomic selection. There has been a deterioration in the genetic trend of HT, and to moderate the decline it is suggested that the HT ABVg should be included in a multitrait economic index with other traits that contribute to farm profit.


Assuntos
Cruzamento , Termotolerância/genética , Animais , Austrália , Cruzamento/normas , Bovinos , Feminino , Técnicas Genéticas/veterinária , Umidade , Lactação , Masculino , Leite/metabolismo , Proteínas do Leite/biossíntese , Reprodutibilidade dos Testes , Temperatura , Termotolerância/fisiologia
7.
Evol Appl ; 10(6): 531-550, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28616062

RESUMO

Genetic diversity underpins the ability of populations to persist and adapt to environmental changes. Substantial empirical data show that genetic diversity rapidly deteriorates in small and isolated populations due to genetic drift, leading to reduction in adaptive potential and fitness and increase in inbreeding. Assisted gene flow (e.g. via translocations) can reverse these trends, but lack of data on fitness loss and fear of impairing population "uniqueness" often prevents managers from acting. Here, we use population genetic and riverscape genetic analyses and simulations to explore the consequences of extensive habitat loss and fragmentation on population genetic diversity and future population trajectories of an endangered Australian freshwater fish, Macquarie perch Macquaria australasica. Using guidelines to assess the risk of outbreeding depression under admixture, we develop recommendations for population management, identify populations requiring genetic rescue and/or genetic restoration and potential donor sources. We found that most remaining populations of Macquarie perch have low genetic diversity, and effective population sizes below the threshold required to retain adaptive potential. Our simulations showed that under management inaction, smaller populations of Macquarie perch will face inbreeding depression within a few decades, but regular small-scale translocations will rapidly rescue populations from inbreeding depression and increase adaptive potential through genetic restoration. Despite the lack of data on fitness loss, based on our genetic data for Macquarie perch populations, simulations and empirical results from other systems, we recommend regular and frequent translocations among remnant populations within catchments. These translocations will emulate the effect of historical gene flow and improve population persistence through decrease in demographic and genetic stochasticity. Increasing population genetic connectivity within each catchment will help to maintain large effective population sizes and maximize species adaptive potential. The approach proposed here could be readily applicable to genetic management of other threatened species to improve their adaptive potential.

8.
J Dairy Sci ; 99(4): 2849-2862, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27037467

RESUMO

Temperature and humidity levels above a certain threshold decrease milk production in dairy cattle, and genetic variation is associated with the amount of lost production. To enable selection for improved heat tolerance, the aim of this study was to develop genomic estimated breeding values (GEBV) for heat tolerance in dairy cattle. Heat tolerance was defined as the rate of decline in production under heat stress. We combined herd test-day recording data from 366,835 Holstein and 76,852 Jersey cows with daily temperature and humidity measurements from weather stations closest to the tested herds for test days between 2003 and 2013. We used daily mean values of temperature-humidity index averaged for the day of test and the 4 previous days as the measure of heat stress. Tolerance to heat stress was estimated for each cow using a random regression model with a common threshold of temperature-humidity index=60 for all cows. The slope solutions for cows from this model were used to define the daughter trait deviations of their sires. Genomic best linear unbiased prediction was used to calculate GEBV for heat tolerance for milk, fat, and protein yield. Two reference populations were used, the first consisted of genotyped sires only (2,300 Holstein and 575 Jersey sires), and the other included genotyped sires and cows (2,189 Holstein and 1,188 Jersey cows). The remainder of the genotyped sires were used as a validation set. All animals had genotypes for 632,003 single nucleotide polymorphisms. When using only genotyped sires in the reference set and only the first parity data, the accuracy of GEBV for heat tolerance in relation to changes in milk, fat, and protein yield were 0.48, 0.50, and 0.49 in the Holstein validation sires and 0.44, 0.61, and 0.53 in the Jersey validation sires, respectively. Some slight improvement in the accuracy of prediction was achieved when cows were included in the reference population for Holsteins. No clear improvements in the accuracy of genomic prediction were observed when data from the second and third parities were included. Correlations of GEBV for heat tolerance with Australian Breeding Values for other traits suggested heat tolerance had a favorable genetic correlation with fertility (0.29-0.39 in Holsteins and 0.15-0.27 in Jerseys), but unfavorable correlations for some production traits. Options to improve heat tolerance with genomic selection in Australian dairy cattle are discussed.


Assuntos
Cruzamento , Bovinos/fisiologia , Temperatura Alta , Seleção Genética , Estresse Fisiológico/genética , Animais , Austrália , Bovinos/genética , Doenças dos Bovinos/genética , Feminino , Fertilidade/genética , Variação Genética , Genótipo , Umidade , Lactação/genética , Masculino , Leite/química , Leite/metabolismo , Paridade/genética , Polimorfismo de Nucleotídeo Único/genética , Gravidez
9.
BMC Genomics ; 16: 993, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26596891

RESUMO

BACKGROUND: Allele specific gene expression (ASE), with the paternal allele more expressed than the maternal allele or vice versa, appears to be a common phenomenon in humans and mice. In other species the extent of ASE is unknown, and even in humans and mice there are several outstanding questions. These include; to what extent is ASE tissue specific? how often does the direction of allele expression imbalance reverse between tissues? how often is only one of the two alleles expressed? is there a genome wide bias towards expression of the paternal or maternal allele; and finally do genes that are nearby on a chromosome share the same direction of ASE? Here we use gene expression data (RNASeq) from 18 tissues from a single cow to investigate each of these questions in turn, and then validate some of these findings in two tissues from 20 cows. RESULTS: Between 40 and 100 million sequence reads were generated per tissue across three replicate samples for each of the eighteen tissues from the single cow (the discovery dataset). A bovine gene expression atlas was created (the first from RNASeq data), and differentially expressed genes in each tissue were identified. To analyse ASE, we had access to unambiguously phased genotypes for all heterozygous variants in the cow's whole genome sequence, where these variants were homozygous in the whole genome sequence of her sire, and as a result we were able to map reads to parental genomes, to determine SNP and genes showing ASE in each tissue. In total 25,251 heterozygous SNP within 7985 genes were tested for ASE in at least one tissue. ASE was pervasive, 89 % of genes tested had significant ASE in at least one tissue. This large proportion of genes displaying ASE was confirmed in the two tissues in a validation dataset. For individual tissues the proportion of genes showing significant ASE varied from as low as 8-16 % of those tested in thymus to as high as 71-82 % of those tested in lung. There were a number of cases where the direction of allele expression imbalance reversed between tissues. For example the gene SPTY2D1 showed almost complete paternal allele expression in kidney and thymus, and almost complete maternal allele expression in the brain caudal lobe and brain cerebellum. Mono allelic expression (MAE) was common, with 1349 of 4856 genes (28 %) tested with more than one heterozygous SNP showing MAE. Across all tissues, 54.17 % of all genes with ASE favoured the paternal allele. Genes that are closely linked on the chromosome were more likely to show higher expression of the same allele (paternal or maternal) than expected by chance. We identified several long runs of neighbouring genes that showed either paternal or maternal ASE, one example was five adjacent genes (GIMAP8, GIMAP7 copy1, GIMAP4, GIMAP7 copy 2 and GIMAP5) that showed almost exclusive paternal expression in brain caudal lobe. CONCLUSIONS: Investigating the extent of ASE across 18 bovine tissues in one cow and two tissues in 20 cows demonstrated 1) ASE is pervasive in cattle, 2) the ASE is often MAE but ranges from MAE to slight overexpression of the major allele, 3) the ASE is most often tissue specific and that more than half the time displays divergent allele specific expression patterns across tissues, 4) across all genes there is a slight bias towards expression of the paternal allele and 5) genes expressing the same parental allele are clustered together more than expected by chance, and there are several runs of large numbers of genes expressing the same parental allele.


Assuntos
Animais não Endogâmicos/genética , Expressão Gênica , Polimorfismo de Nucleotídeo Único , Alelos , Animais , Bovinos , Mapeamento Cromossômico , Feminino , Perfilação da Expressão Gênica/métodos , Impressão Genômica , Pulmão/metabolismo , Masculino , Especificidade de Órgãos , Análise de Sequência de RNA/métodos , Timo/metabolismo
10.
Mol Ecol Resour ; 11(1): 219-22, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21429127

RESUMO

This article documents the addition of 229 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acacia auriculiformis × Acacia mangium hybrid, Alabama argillacea, Anoplopoma fimbria, Aplochiton zebra, Brevicoryne brassicae, Bruguiera gymnorhiza, Bucorvus leadbeateri, Delphacodes detecta, Tumidagena minuta, Dictyostelium giganteum, Echinogammarus berilloni, Epimedium sagittatum, Fraxinus excelsior, Labeo chrysophekadion, Oncorhynchus clarki lewisi, Paratrechina longicornis, Phaeocystis antarctica, Pinus roxburghii and Potamilus capax. These loci were cross-tested on the following species: Acacia peregrinalis, Acacia crassicarpa, Bruguiera cylindrica, Delphacodes detecta, Tumidagena minuta, Dictyostelium macrocephalum, Dictyostelium discoideum, Dictyostelium purpureum, Dictyostelium mucoroides, Dictyostelium rosarium, Polysphondylium pallidum, Epimedium brevicornum, Epimedium koreanum, Epimedium pubescens, Epimedium wushanese and Fraxinus angustifolia.


Assuntos
Bases de Dados de Ácidos Nucleicos , Dictyostelium/genética , Epimedium/genética , Haptófitas/genética , Repetições de Microssatélites , Dados de Sequência Molecular
11.
Waste Manag Res ; 28(4): 289-97, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19723822

RESUMO

Fuel consumption during seven different daily activities of a garbage co-collection truck and a normal packer truck was estimated from the trucks' global positioning system (GPS) data and fuel consumption records. The co-collection and the normal garbage packer consumed approximately 1.8 L and 1.26 L of diesel per km, respectively, while travelling within the collection areas. Using these fuel rates and the GPS data, the results show that both types of trucks consumed more than 60% of daily total fuel while actually collecting waste on the route. The average daily fuel consumption was 2-4 times higher on rural routes compared to urban areas. Fuel consumption varied significantly depending on the housing density along the collection route. In addition, approximately 5-6 times as much fuel was required to collect a kilogram of waste on a rural route compared to an urban route. Potential methods of reducing fuel consumption were examined. Consistent use of optimal collection routes could potentially save an average of 7.5 L of fuel per truck per day. Reducing the loading time per stop was also studied, but the results suggest that this method does not have significant potential to reduce fuel consumption.


Assuntos
Conservação de Recursos Energéticos , Gasolina , Eliminação de Resíduos/métodos , Cidades , Veículos Automotores
12.
Mar Biotechnol (NY) ; 12(5): 506-15, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19941027

RESUMO

The culture of green mussel (Perna viridis) in the Gulf of Thailand depends on natural spat which are believed to come from spawning grounds adjacent to major river mouths. In the present paper, genetic diversity of spatial and temporal populations of green mussel in the Gulf of Thailand was investigated using five microsatellite loci. The results showed moderate genetic variation of all 11 populations (averaged number of alleles per locus, A = 10.4-12.2; effective number of alleles per locus, A(e) = 5.36-6.59; mean allelic richness, A(r) = 10.23-12.06; observed heterozygosity, H(o) = 0.52-0.63, and expected heterozygosity, H(e) = 0.66-0.73) without significant differences among populations. No sign of bottleneck or genetic disequilibrium was observed. Genetic differentiation among spatial populations was low (F (ST) = 0.0046, CI(0.95) = 0.0020-0.0083 for the samples collected in January, 2007, and F (ST) = 0.0088, CI(0.95) = 0.0010-0.0162 for the samples collected in July, 2007) while temporal variation was significant as revealed by the analysis of molecular variance. Multidimensional scaling separated temporal population groups with minor exception. The assignment test revealed that most of the recruits were from other populations.


Assuntos
Aquicultura , Variação Genética/genética , Genética Populacional , Perna (Organismo)/classificação , Perna (Organismo)/genética , Animais , Água do Mar , Especificidade da Espécie , Tailândia
13.
Ambio ; 38(1): 24-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19260343

RESUMO

Aquaculture is seen as an alternative to meeting the widening gap in global rising demand and decreasing supply for aquatic food products. Asia, the epicenter of the global aquaculture industry, accounts for over 90% of the global aquaculture production quantity and about 80% of the value. Asian aquaculture, as with global aquaculture, is dependent to a significant extent on alien species, as is the case for all the major food crops and husbanded terrestrial animals. However, voluntary and or accidental introduction of exotic aquatic species (alien species) is known to negatively impact local biodiversity. In this relatively young food production industry, mitigating the dependence on alien species, and thereby minimizing potential negative impacts on biodiversity, is an imperative for a sustainable future. In this context an attempt is made in this synthesis to understand such phenomena, especially with reference to Asian inland finfish, the mainstay of global aquaculture production. It is pointed out that there is potential for aquaculture, which is becoming an increasingly important food production process, not to follow the past path of terrestrial food crops and husbanded animals in regard to their negative influences on biodiversity.


Assuntos
Aquicultura/métodos , Biodiversidade , Peixes/fisiologia , Animais , Ásia , Conservação dos Recursos Naturais , Água Doce , Dinâmica Populacional
15.
Mar Biotechnol (NY) ; 9(3): 352-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17549563

RESUMO

Sequence variation of the mitochondrial DNA 16S rRNA region of the Asian moon scallop, Amusium pleuronectes, was surveyed in seven populations along the coast of Thailand. A total of 16 unique haplotypes were detected among 174 individuals with a total 27 variable sites out of 534 bp sequenced. The mitochondrial haplotypes grouped into two distinct arrays (estimated to differ by about 2.62% to 2.99% nucleotide divergence) that characterized samples collected from the Gulf of Thailand versus the Andaman Sea. Low levels of intrapopulation variation were observed, while in contrast, significant divergence was observed between populations from the Gulf of Thailand and Andaman Sea. Results of AMOVA reveal a high F (ST) value (0.765) and showed that the majority of the total genetic variance (76.03%) occurred among groups (i.e., Andaman Sea and the Gulf of Thailand) and little among populations within the group (0.52%) and within populations (23.45%). The genetic differentiation between the populations recorded in the present study is similar to that observed in a variety of marine species in the Indo-Pacific. The implications of the findings for management of A. pleuronectes genetic resources in Thailand are discussed.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Pectinidae/genética , Animais , Sequência de Bases , RNA Ribossômico 16S/genética , Tailândia
16.
Gene ; 331: 65-72, 2004 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-15094192

RESUMO

The complete mitochondrial DNA sequence was determined for the Australian freshwater crayfish Cherax destructor (Crustacea: Decapoda: Parastacidae). The 15,895-bp genome is circular with the same gene composition as that found in other metazoans. However, we report a novel gene arrangement with respect to the putative arthropod ancestral gene order and all other arthropod mitochondrial genomes sequenced to date. It is apparent that 11 genes have been translocated (ND1, ND4, ND4L, Cyt b, srRNA, and tRNAs Ser(UGA), Leu(CUN), Ile, Cys, Pro, and Val), two of which have also undergone inversions (tRNAs Pro and Val). The 'duplication/random loss' mechanism is a plausible model for the observed translocations, while 'intramitochondrial recombination' may account for the gene inversions. In addition, the arrangement of rRNA genes is incompatible with current mitochondrial transcription models, and suggests that a different transcription mechanism may operate in C. destructor.


Assuntos
Astacoidea/genética , DNA Mitocondrial/genética , Animais , Sequência de Bases , DNA Mitocondrial/química , Ordem dos Genes , Rearranjo Gênico , Dados de Sequência Molecular , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência de DNA
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