diversity estimates
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Author(s):  
Shalini Singh ◽  
B. Singh ◽  
V.R. Sharma ◽  
M. Kumar ◽  
U. Sirohi

Background: The study was undertaken to assess the genetic diversity and genetic structure among fifty-five pea accessions using morphological traits and SSR markers. Methods: A total of 55 pea accessions were analyzed using eleven phenotypic traits and twenty SSR markers. The data obtained by morphological and molecular profiling was used for the analysis of genetic diversity and for the estimation of genetic diversity estimates, correlation, principal components analysis and population structure. Result: This study reveals that majority of genetic variation was due to variation within population and were clustered into two distinct groups, which reveals a high admixture within individuals. Accessions viz., VRP-82, VRP-320, VRP-194, VRP-375, EC-97280 and EC-8724, showed great diversity as compared to the other accessions based on both morphological and molecular markers. These accessions may assist in developing and planning breeding strategies aimed to produce new varieties in the future.


2021 ◽  
pp. jrheum.210626
Author(s):  
Chay Bae ◽  
Michael Cheng ◽  
Christina N. Kraus ◽  
Sheetal Desai

Objective To investigate the availability of images representing black, indigenous, and people of color in rheumatology educational resources. Methods Colorized images were collected from 5 major educational resources and cataloged by educational resources they came from, underlying rheumatic conditions, and skin type. Fitzpatrick skin type (FST) was used to categorize images into "light", "dark", or "indeterminate". The images were initially scored by a fellow in the Division of Rheumatology and subsequently validated by a faculty member from the Department of Dermatology. Results Of the thousands of images reviewed, 1604 images met study criteria. Fitzpatrick skin type validation from Dermatology resulted in the re-coding of 111 images. The final scoring revealed 86% of the images to be light skin, 9% of images to be dark skin, and 5% of images to be indeterminate. Conclusion The paucity of dark skin images in rheumatology resources is incongruent with current diversity estimates in the United States. Significant efforts should be made to incorporate images of black, indigenous, and people of color into educational resources.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 407-407
Author(s):  
Ki Beom Jang ◽  
Sung Woo Kim

Abstract This study aimed to evaluate supplemental effects of milk carbohydrates in whey permeate on jejunal mucosa-associated microbiota in nursery pigs during 7 to 11 kg BW. A total of 720 pigs at 7.5 kg BW were allotted to 6 treatments (6 pens/treatment and 20 pigs/pen). Treatments were 6 levels of whey permeate supplementation (0, 3.75, 7.50, 11.25, 15.00, and 18.75%) and fed to pigs for 11 d. On d 11, 36 pigs representing median BW of each pen were euthanized to collect the jejunal mucosa to evaluate microbiota in the jejunum by 16S rDNA sequencing. Data were analyzed using contrasts in MIXED procedure of SAS. Whey permeate contained 76.3% lactose and 0.4% milk oligosaccharides. Increasing whey permeate supplementation from 0 to 18.75% did not affect the alpha-diversity estimates of microbiota. Whey permeate supplementation tended to decrease (P = 0.073, 1.59 to 1.22) Firmicutes:Bacteroidetes compared with no addition of whey permeate. Increasing whey permeate supplementation tended to linearly increase Bifidobacteriaceae (P = 0.089, 0.73 to 1.11), decrease Enterobacteriaceae (P = 0.091, 1.04 to 0.52), decrease Stretococcaceae (P = 0.094, 1.50 to 0.71), and caused quadratic changes (P < 0.05) on Lactobacillaceae (maximum: 9.14% at 12.91% whey permeate). Increasing whey permeate supplementation caused a quadratic change (P < 0.05) on Lactobacillus_Salivarius (maximum: 0.92% at 7.35% whey permeate) and tended to cause quadratic changes on Lactobacillus_Rogosae (P = 0.083; maximum: 0.53% at 8.45% whey permeate) and Lactobacillus_Mucosae (P = 0.092; maximum: 0.70% at 6.98% whey permeate). In conclusion, supplementation of whey permeate as sources of lactose and milk oligosaccharides at a range from 7 to 13% seems to be beneficial to nursery pigs by increasing the abundance of lactic acid-producing bacteria in the jejunal mucosa.


2021 ◽  
Vol 12 ◽  
Author(s):  
Johnathon M. Shook ◽  
Daniela Lourenco ◽  
Asheesh K. Singh

The lowering genotyping cost is ushering in a wider interest and adoption of genomic prediction and selection in plant breeding programs worldwide. However, improper conflation of historical and recent linkage disequilibrium between markers and genes restricts high accuracy of genomic prediction (GP). Multiple ancestors may share a common haplotype surrounding a gene, without sharing the same allele of that gene. This prevents parsing out genetic effects associated with the underlying allele of that gene among the set of ancestral haplotypes. We present “Parental Allele Tracing, Recombination Identification, and Optimal predicTion” (i.e., PATRIOT) approach that utilizes marker data to allow for a rapid identification of lines carrying specific alleles, increases the accuracy of genomic relatedness and diversity estimates, and improves genomic prediction. Leveraging identity-by-descent relationships, PATRIOT showed an improvement in GP accuracy by 16.6% relative to the traditional rrBLUP method. This approach will help to increase the rate of genetic gain and allow available information to be more effectively utilized within breeding programs.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yin Cheong Aden Ip ◽  
Jia Jin Marc Chang ◽  
Kelvin K. P. Lim ◽  
Zeehan Jaafar ◽  
Benjamin J. Wainwright ◽  
...  

Abstract Background Sharks and rays are some of the most threatened marine taxa due to the high levels of bycatch and significant demand for meat and fin-related products in many Asian communities. At least 25% of shark and ray species are considered to be threatened with extinction. In particular, the density of reef sharks in the Pacific has declined to 3–10% of pre-human levels. Elasmobranchs are thought to be sparse in highly urbanised and turbid environments. Low visibility coupled with the highly elusive behaviour of sharks and rays pose a challenge to diversity estimation and biomonitoring efforts as sightings are limited to chance encounters or from carcasses ensnared in nets. Here we utilised an eDNA metabarcoding approach to enhance the precision of elasmobranch diversity estimates in urbanised marine environments. Results We applied eDNA metabarcoding on seawater samples to detect elasmobranch species in the hyper-urbanised waters off Singapore. Two genes—vertebrate 12S and elasmobranch COI—were targeted and amplicons subjected to Illumina high-throughput sequencing. With a total of 84 water samples collected from nine localities, we found 47 shark and ray molecular operational taxonomic units, of which 16 had species-level identities. When data were compared against historical collections and contemporary sightings, eDNA detected 14 locally known species as well as two potential new records. Conclusions Local elasmobranch richness uncovered by eDNA is greater than the seven species sighted over the last two decades, thereby reducing phantom diversity. Our findings demonstrate that eDNA metabarcoding is effective in detecting shark and ray species despite the challenges posed by the physical environment, granting a more consistent approach to monitor these highly elusive and threatened species.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joanna Malukiewicz ◽  
Reed A. Cartwright ◽  
Jorge A. Dergam ◽  
Claudia S. Igayara ◽  
Patricia A. Nicola ◽  
...  

AbstractThe Brazilian buffy-tufted-ear marmoset (Callithrix aurita), one of the world’s most endangered primates, is threatened by anthropogenic hybridization with exotic, invasive marmoset species. As there are few genetic data available for C. aurita, we developed a PCR-free protocol with minimal technical requirements to rapidly generate genomic data with genomic skimming and portable nanopore sequencing. With this direct DNA sequencing approach, we successfully determined the complete mitogenome of a marmoset that we initially identified as C. aurita. The obtained nanopore-assembled sequence was highly concordant with a Sanger sequenced version of the same mitogenome. Phylogenetic analyses unexpectedly revealed that our specimen was a cryptic hybrid, with a C. aurita phenotype and C. penicillata mitogenome lineage. We also used publicly available mitogenome data to determine diversity estimates for C. aurita and three other marmoset species. Mitogenomics holds great potential to address deficiencies in genomic data for endangered, non-model species such as C. aurita. However, we discuss why mitogenomic approaches should be used in conjunction with other data for marmoset species identification. Finally, we discuss the utility and implications of our results and genomic skimming/nanopore approach for conservation and evolutionary studies of C. aurita and other marmosets.


Author(s):  
Marc Domènech ◽  
Owen S. Wangensteen ◽  
Alba Enguídanos ◽  
Jagoba Malumbres-Olarte ◽  
Miquel Arnedo

Because of their challenging taxonomy, arthropods are traditionally underrepresented in biological inventories and monitoring programs. However, arthropods are the largest component of biodiversity, and no assessment can be considered informative without including them. Arthropod immature stages are often discarded during sorting, despite frequently representing more than half of the collected individuals. To date, little effort has been devoted to characterising the impact of discarding non-adult specimens on our diversity estimates. Here, we use a metabarcoding approach to analyse spiders from white oak communities in the Iberian Peninsula collected with standardised protocols, to assess (1) the contribution of juvenile stages to local diversity estimates, and (2) their effect on the diversity patterns inferred across communities. We further investigate the ability of metabarcoding to inform on abundance. We obtained 363 and 331 species as adults and juveniles, respectively. Species represented only by juveniles represented an increase of 35% with respect to those identified from adults in the whole sampling. Differences in composition between communities were greatly reduced when immature stages were taken considered, especially across latitudes. Moreover, our results revealed that metabarcoding data are to a certain extent quantitative, but some sort of taxonomic conversion factor may be necessary to provide accurate informative estimates. Although our findings do not question the relevance of the information provided by adult-based inventories, they also reveal that juveniles provide a novel and relevant layer of knowledge that, especially in areas with marked seasonality, may influence our interpretations, providing more accurate information from standardised biological inventories.


2021 ◽  
Author(s):  
Rory Gibb ◽  
Gregory F Albery ◽  
Nardus F Mollentze ◽  
Evan A Eskew ◽  
Liam Brierley ◽  
...  

Host-virus association data form the backbone of research into eco-evolutionary drivers of viral diversity and host-level zoonotic risk. However, knowledge of the wildlife virome is inherently constrained by historical discovery effort, and there are concerns that the reliability of ecological inference from host-virus data may be undermined by taxonomic and geographical sampling biases. Here, we evaluate whether current estimates of host-level viral diversity in wild mammals are stable enough to be considered biologically meaningful, by analysing a comprehensive dataset of discovery dates of 6,571 unique mammal host-virus associations between 1930 and 2018. We show that virus discovery rates in mammal hosts are still either constant or accelerating, with little evidence of declines towards viral richness asymptotes in even highly-sampled hosts. Consequently, inference of relative viral richness across host species has been unstable over time, particularly in bats, where intensified surveillance since the early 2000s caused a rapid rearrangement of species' ranked viral richness. Our results show that comparative inference of host-level virus diversity across mammals is highly sensitive to even short-term changes in sampling effort. We advise caution to avoid overinterpreting patterns in current data, since our findings suggest that an analysis conducted today could feasibly draw quite different conclusions than one conducted only a decade ago.


ZooKeys ◽  
2021 ◽  
Vol 1044 ◽  
pp. 797-813
Author(s):  
Stephanie A. Dole ◽  
Jiri Hulcr ◽  
Anthony I. Cognato

Canopy fogging was used to sample the diversity of bark and ambrosia beetles (Coleoptera, Curculionidae, Scolytinae) at two western Amazonian rainforest sites in Ecuador. Sampling was conducted by Dr Terry Erwin and assistants from 1994–2006 and yielded 1158 samples containing 2500 scolytine specimens representing more than 400 morphospecies. Here, we analyze a subset of these data representing two ecological groups: true bark beetles (52 morphospecies) and ambrosia beetles (69 morphospecies). A high percentage of these taxa occurred as singletons and doubletons and their species accumulation curves did not reach an asymptote. Diversity estimates placed the total scolytine species richness for this taxon subset present at the two sites between 260 and 323 species. The α-diversity was remarkably high at each site, while the apparently high β-diversity was an artifact of undersampling, as shown by a Monte Carlo resampling analysis. This study demonstrates the utility of canopy fogging for the discovery of new scolytine taxa and for approximate diversity assessment, but a substantially greater sampling effort would be needed for conclusive alpha as well as beta diversity estimates.


Author(s):  
Alessandra Bernardi ◽  
Martina Iannacito ◽  
Duccio Rocchini

AbstractWe propose a new method to estimate plant diversity with Rényi and Rao indexes through the so called High Order Singular Value Decomposition (HOSVD) of tensors. Starting from NASA multi-spectral images we evaluate diversity and we compare original diversity estimates with those realized via the HOSVD compression methods for big data. Our strategy turns out to be extremely powerful in terms of memory storage and precision of the outcome. The obtained results are so promising that we can support the efficiency of our method in the ecological framework.


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