scholarly journals Torus Mandibularis: Etiology and Bioarcheological Utility

2018 ◽  
Vol 19 (1) ◽  
pp. 1-14
Author(s):  
Brenna Hassett

Torus mandibularis is a non-metric traitcommonly recorded in bioarcheological investigationand often included in the battery of non-metric traitsused to analyse biological distance among populations.However, there is considerable debate regarding theetiology of the trait, with genetic and environmentalfactors both having been posited as the primary factorin torus development. This study of 498 individuals,drawn from eight archeological samples, investigatesthe variation in torus frequency in different groups asdefined by sample, age, sex, and measures of functionalstress. Frequencies varied significantly among bothsamples and dental attrition categories, supportingthe idea that mandibular tori are a threshold trait,influenced by both genetic and environmental factors.Results of this study suggest the utility of mandibulartori in bioarchaeology may lie outside of biodistanceanalyses that rely on the high heritability quotient ofnon-metric traits to establish population distances.

2016 ◽  
Vol 61 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Babar Saleem ◽  
Abdus Khan ◽  
Muhammad Shahzad ◽  
Fahid Ijaz

Heritability estimates provide information about the traits that are transmitted from parents to their offsprings and it has a crucial role in selection criteria to improve grain yield. The purpose of the present study was to compute heritability and genetic advance of seven F2 populations derived through cross combinations of five parental varieties/lines of bread wheat Iqbal-2000, Lasani- 2008, 9444, 9432 and 9436. Data were recorded for seven metric traits: plant height, days to heading, flag leaf area, peduncle length, number of kernels per spike, kernel weight per spike and grain yield per plant. The estimates of heritability were low to high for all the traits studied except for kernel weight per spike which had a moderate to high value of heritability. Results depict that all the mentioned traits can be enhanced easily due to high values of heritability and phenotypic variations. The cross combinations 9436 ? Iqbal-2000 and 9436 ? Lasani-2008 had high heritability for most of the traits. Therefore, selection could be practiced among wheat crosses with special emphasis on crosses, namely 9436 ? Iqbal-2000, to improve grain yield per plant.


Author(s):  
D. L. Callahan ◽  
Z. Ball ◽  
H. M. Phillips ◽  
R. Sauerbrey

Ultraviolet laser-irradiation can be used to induce an insulator-to-conductor phase transition on the surface of Kapton polyimide. Such structures have potential applications as resistors or conductors for VLSI applications as well as general utility electrodes. Although the percolative nature of the phase transformation has been well-established, there has been little definitive work on the mechanism or extent of transformation. In particular, there has been considerable debate about whether or not the transition is primarily photothermal in nature, as we propose, or photochemical. In this study, cross-sectional optical microscopy and transmission electron microscopy are utilized to characterize the nature of microstructural changes associated with the laser-induced pyrolysis of polyimide.Laser-modified polyimide samples initially 12 μm thick were prepared in cross-section by standard ultramicrotomy. Resulting contraction in parallel to the film surface has led to distortions in apparent magnification. The scale bars shown are calibrated for the direction normal to the film surface only.


Author(s):  
Lubos SMUTKA ◽  
Irena BENEŠOVÁ ◽  
Patrik ROVNÝ ◽  
Renata MATYSIK-PEJAS

Sugar is one of the most important elements in human nutrition. The Common Market Organisation for sugar has been a subject of considerable debate since its establishment in 1968. The European agricultural market has been criticized for its heavy regulations and subsidization. The sugar market is one of the most regulated ones; however, this will change radically in 2017 when the current system of production quotas will end. The current EU sugar market changed is structure during the last several decades. The significant number of companies left the market and EU internal sugar market became more concentrated. The aim of this paper is presentation characteristics of sugar market with respect to the supposed market failure – reduction in competition. The analysis also identifies the main drivers and determinants of the EU especially quota sugar market. In relation to paper’s aim the following results are important. The present conditions of the European sugar market have led to market failure when nearly 75 % (10 million tonnes) of the quota is controlled by five multinational companies only. These multinational alliances (especially German and French one) are also taking control over the production capacities of their subsidiaries. In most countries, this causes serious problems as the given quota is controlled by one or two producers only. This is a significant indicator of market imperfection. The quota system cannot overcome the problem of production quotas on the one hand and the demand on the other; furthermore, it also leads to economic inefficiency. The current EU sugar market is under the control of only Sudzucker, Nordzucker, Pfeifer and Langen, Tereos and ABF.


Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Yohanis Amos Mustamu ◽  
Trikoesoemaningtyas Trikoesoemaningtyas ◽  
Desta Wirnas ◽  
Didy Sopandie ◽  
Darman M. Arsyad

The objective of this study was to collect information on genetic parameter and agronomy character of soybean F4 generation in the low light intensity condition. The parameter was tested to 130 lines F4 which are produced by Balai Besar Pengkajian dan Pengembangan Teknologi Pertanian (BBP2TP) Boor and the genotype of Sibayak, Tegal, Tanggamus, and Argomulyo were used as controls. The experiment was conducted in the university�s experimental field in Cikabayan, from September to December 2007. A total of 130 advance (F4) soybean lines were evaluated under shading in an augmented design experiment. The result of this study showed that all character has low genetic coefficient. The weight character of 25 grains has a considerably high heritability number in low li


Author(s):  
Saheb Foroutaifar

AbstractThe main objectives of this study were to compare the prediction accuracy of different Bayesian methods for traits with a wide range of genetic architecture using simulation and real data and to assess the sensitivity of these methods to the violation of their assumptions. For the simulation study, different scenarios were implemented based on two traits with low or high heritability and different numbers of QTL and the distribution of their effects. For real data analysis, a German Holstein dataset for milk fat percentage, milk yield, and somatic cell score was used. The simulation results showed that, with the exception of the Bayes R, the other methods were sensitive to changes in the number of QTLs and distribution of QTL effects. Having a distribution of QTL effects, similar to what different Bayesian methods assume for estimating marker effects, did not improve their prediction accuracy. The Bayes B method gave higher or equal accuracy rather than the rest. The real data analysis showed that similar to scenarios with a large number of QTLs in the simulation, there was no difference between the accuracies of the different methods for any of the traits.


2021 ◽  
pp. 1-10
Author(s):  
Sophie E. Legge ◽  
Marcos L. Santoro ◽  
Sathish Periyasamy ◽  
Adeniran Okewole ◽  
Arsalan Arsalan ◽  
...  

Abstract Schizophrenia is a severe psychiatric disorder with high heritability. Consortia efforts and technological advancements have led to a substantial increase in knowledge of the genetic architecture of schizophrenia over the past decade. In this article, we provide an overview of the current understanding of the genetics of schizophrenia, outline remaining challenges, and summarise future directions of research. World-wide collaborations have resulted in genome-wide association studies (GWAS) in over 56 000 schizophrenia cases and 78 000 controls, which identified 176 distinct genetic loci. The latest GWAS from the Psychiatric Genetics Consortium, available as a pre-print, indicates that 270 distinct common genetic loci have now been associated with schizophrenia. Polygenic risk scores can currently explain around 7.7% of the variance in schizophrenia case-control status. Rare variant studies have implicated eight rare copy-number variants, and an increased burden of loss-of-function variants in SETD1A, as increasing the risk of schizophrenia. The latest exome sequencing study, available as a pre-print, implicates a burden of rare coding variants in a further nine genes. Gene-set analyses have demonstrated significant enrichment of both common and rare genetic variants associated with schizophrenia in synaptic pathways. To address current challenges, future genetic studies of schizophrenia need increased sample sizes from more diverse populations. Continued expansion of international collaboration will likely identify new genetic regions, improve fine-mapping to identify causal variants, and increase our understanding of the biology and mechanisms of schizophrenia.


Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 947
Author(s):  
Marius Budeanu ◽  
Ecaterina Nicoleta Apostol ◽  
Emanuel Besliu ◽  
Vlad Emil Crișan ◽  
Any Mary Petritan

In a changing climate, forest managers need to select productive and climate-change-resilient tree species and provenances. Therefore, assessing the growth response of provenances growing in field trials to climate provides useful information for identifying the more appropriate provenance or variety. To determine the genetic gain through selection of the most productive and resilient families and to decipher the role of crown forms of Norway spruces (Picea abies (L.) Karst.), we used 24 families with a classical crown (pyramidalis) and 24 with a narrow crown (pendula) from eight provenances, growing in a 25-year-old comparative trial. The annual wood characteristics (ring width and early- and latewood), the wood resistance (expressed by latewood proportion (LWP)), and the growth response to climate of the two spruce crown forms were investigated. No significant differences between the two spruce forms were found regarding the ring width characteristics. However, three pendula families of Stâna de Vale I provenance exhibited the highest LWP and could be included in a future selection strategy, the respective trait having also high heritability. Radial growth was positively and significantly correlated with previous September and current July precipitation and negatively with current June temperature. Both spruce forms showed good recovery capacity after a drought event.


Author(s):  
Darlene Ana Souza Duarte ◽  
Martine Schroyen ◽  
Rodrigo Reis Mota ◽  
Sylvie Vanderick ◽  
Nicolas Gengler

AbstractBoar taint is an unpleasant odor in male pig meat, mainly caused by androstenone, skatole, and indole, which are deposited in the fat tissue. Piglet castration is the most common practice to prevent boar taint. However, castration is likely to be banished in a few years due to animal welfare concerns. Alternatives to castration, such as genetic selection, have been assessed. Androstenone and skatole have moderate to high heritability, which makes it feasible to select against these compounds. This review presents the latest results obtained on genetic selection against boar taint, on correlation with other traits, on differences in breeds, and on candidate genes related to boar taint. QTLs for androstenone and skatole have been reported mainly on chromosomes 6, 7, and 14. These chromosomes were reported to contain genes responsible for synthesis and degradation of androstenone and skatole. A myriad of work has been done to find markers or genes that can be used to select animals with lower boar taint. The selection against boar taint could decrease performance of some reproduction traits. However, a favorable response on production traits has been observed by selecting against boar taint. Selection results have shown that it is possible to reduce boar taint in few generations. In addition, modifications in diet and environment conditions could be associated with genetic selection to reduce boar taint. Nevertheless, costs to measure and select against boar taint should be rewarded with incentives from the market; otherwise, it would be difficult to implement genetic selection.


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