fat tail
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2021 ◽  
Vol 6 (1) ◽  
pp. 15
Author(s):  
Max-Olivier Hongler

In this paper, a dissipative version of the Benjamin–Ono dynamics is shown to faithfully model the collective evolution of swarms of scalar Cauchy stochastic agents obeying a follow-the-leaderinteraction rule. Due to the Hilbert transform, the swarm dynamic is described by nonlinear and non-local dynamics that can be solved exactly. From the mutual interactions emerges a fat-tail soliton that can be obtained in a closed analytic form. The soliton median evolves nonlinearly with time. This behaviour can be clearly understood from the interaction of mutual agents.


2021 ◽  
Author(s):  
Massoud - Talebkhan Garoussi ◽  
Omid Mavadati ◽  
Mohammad Ali Bahonar ◽  
Mehran Dabiri

Abstract Sheep are considered short-day breeders. Exposure of rams to anestrus ewes results in an increase in LH secretion. The aims of this study was to determine whether the presence and exposure of rams can effect on reproductive performance such as: pregnancy rate, litter size, sex of lamb, fecundity rate and prolificacy rate of fat tail Iranian Shaal breed ewes in non-breeding season using progesterone (p4) analogue with or without equine chorionic gonadotropin (eCG). Totally, 100 ewes out of 138 non-cyclic ewes with <0.5ng/ml P4 were selected for this study. They were aged 2 to >7 years old. They were stratified to two groups (control and treatment). The ewes in treatment and control groups received 13 days a sponge containing 60 mg medroxyprogesterone acetate (MPA). The treatment group consists of 3 subgroups and each group contains 25 ewes equally. They were included: 1- P4, eCG and Ram exposure. 2- P4 and ram exposure. 3- P4 and eCG. Ewes in control group received only P4. The ewes were located in isolated corrals for 40 days. The ram to ewe ratio was 1 to 5. Twenty healthy rams were housed in an isolated pen from ewes with distance 1500 m during 40 days. Rams exposed three days before sponge withdraw (day 10). They were separated by considerable distance (2 meters) using fence. The related groups received 500 IU eCG on the day of sponge removal (day 13). The rams were released into the ewe flock after removing the sponge in treatment and control groups. Pregnancy diagnosis performed using transabdominal ultrasonography. The obtained data analyzed using SPSS version 16. The conception rate in treatment and control groups were differed significantly (P<0.01). The conception rate in P4+ram exposure+ eCG, P4+ramexposure and P4+ eCG were 96%(no.24), 80%(no.20) and 88%(no.22), respectively. However, the conception rate in control group was 60% (no. 15). The fecundity rates were 136%, 100% and 124% in treatment subgroups, however, it was 84% in control group, respectively. There were no significant differences among genus and weight of lambs in treatments subgroups and control group (P>0.05). It is concluded that ram exposure can increase significantly reproductive performance in non-breeding season fat tailed ewes Shaal breed.


2021 ◽  
Vol 13 (22) ◽  
pp. 12769
Author(s):  
Thordur Vikingur Fridgeirsson ◽  
Helgi Thor Ingason ◽  
Svana Helen Björnsdottir ◽  
Agnes Yr Gunnarsdottir

In this rapidly changing and fast-growing world, sustainability is an important paradigm. However, the constantly growing level of uncertainty leads to increased strain in decision making. This results in a growing need for a more effective and extensive approach for identifying project risk in particular events that are not easily detected but can have a severe impact, sometimes referred to as Black Swans or “fat tail” events. The VUCA meter is a normative approach to identify project risk by assessing in a structured way events that may be volatile, uncertain, complex, and ambiguous and might contribute to the project risk. In this study, the VUCA meter is benchmarked against a traditional risk identification process as recommended by PMI®. Firstly, two workshops, each referring to the respective risk identification method, were conducted. Secondly, a Delphi survey was run to investigate if the VUCA meter would capture Black Swan risk events that are bypassed by the traditional risk identification approach. The results clearly indicate that the VUCA meter can be developed to be a significant addition to the conventional risk identification process for large projects that are at an early stage. The VUCA meter facilitates a discussion that gets people to think beyond the traditional framework for identifying project risk factors. As a consequence, “fat tail” events, that are not apprehended with the conventional technique, are captured by the VUCA meter.


2021 ◽  
Author(s):  
Mohammad Hossein Moradi ◽  
Ardeshir Nejati-Javaremi ◽  
Mohammad Moradi-Shahrbabak ◽  
Ken G. Dodds ◽  
Rudiger Brauning ◽  
...  

Abstract Background Fatness related traits are economically very important in sheep production and are associated with serious diseases in humans. The fat tail is a phenotype that divides domesticated sheep into two major groups. The objective of the present study is to refine the map location of candidate regions associated with fat deposition, obtained via two separate whole genome scans contrasting thin and fat tail breeds, and to determine the nature of the selection occurring in these regions using hitchhiking approach. Results Zel (thin tail) and Lori-Bakhtiari (fat tail) breed samples that had previously been run on the Illumina Ovine 50k BeadChip, were genotyped with a denser set of SNPs in the three candidate regions using a Sequenom Mass ARRAY platform. Statistical tests were then performed using different and complementary methods based on either site frequency (FST and Median homozygosity) or haplotype (iHS and XP-EHH). Results from candidate regions on chromosome 5 and X revealed clear evidence of selection with the derived haplotypes that were consistent with selection to near fixation for the haplotypes affecting fat tail size in the fat tail breed. Analysis of the candidate region on chromosome 7 indicated that selection differentiated the beneficial alleles between breeds and homozygosity has increased in the thin tail breed which also had the ancestral haplotype. These results enabled us to confirm the signature of selection in these regions and refine the critical intervals from 113kb, 201kb and 2,831kb to 28kb, 142kb and 1,006kb on chromosome 5, 7 and X respectively. These regions contain several genes associated with fat metabolism or developmental processes consisting TCF7 and PPP2CA (OAR5), PTGDR and NID2 (OAR7), AR, EBP, CACNA1F, HSD15B, SLC35A2, BMP15, WDR13 and RBM3 (OAR X), each of which could potentially be the actual target of selection. Study of core haplotypes alleles in our regions of interest also supported the hypothesis that the first domesticated sheep were thin tailed and fat tail animals were developed later. Conclusions Our results provide a comprehensive assessment of how and where selection has affected the patterns of variation in candidate regions associated with fat deposition in thin and fat tail sheep breeds. The hitchhiking mapping approach in this study was novel in the sense that most of the exploratory genome scan studies in domestic animals have not clarified the signal from the candidate regions, probably due to the lack of suitable genomic resources.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Garoussi MT ◽  
◽  
Ragh MJ ◽  

Occasionally herniation of abdominal wall may occur in ewe due to rupture of Prepubic tendon and muscles of abdominal walls during the last month of pregnancy. Subsequently, different parts of the gastrointestinal tract get out of their original location. Only one (0.2%) out of 500 ewes Shal fat-tail breed suffered from herniation due to the rupture of Prepubic tendon in Amin Abad research institution of Faculty of Veterinary Medicine, University of Tehran, Tehran-Iran. It was 7 years old. It was lambed normally for four times. The ewe delivered normally without any sign of dystocia in the last lambing. It was suffered due to Prepubic tendon rupture after 8 days of parturition. In abdominal exam, the signs of herniation were cleared typically. The herniation could be rejected in abdominal exam. This is the first report of rupture of Prepubic tendon and herniation of abdominal wall in ewe after parturition in Iran. It can be due to the weakness of abdominal wall muscles in aged ewes.


Gene ◽  
2021 ◽  
Vol 781 ◽  
pp. 145492
Author(s):  
Xinyue Wang ◽  
Chao Fang ◽  
Haiying He ◽  
Hang Cao ◽  
Lingling Liu ◽  
...  
Keyword(s):  
Rna Seq ◽  
Fat Tail ◽  

Mathematics ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 958
Author(s):  
Maike Tormählen ◽  
Galiya Klinkova ◽  
Michael Grabinski

Statistical significance measures the reliability of a result obtained from a random experiment. We investigate the number of repetitions needed for a statistical result to have a certain significance. In the first step, we consider binomially distributed variables in the example of medication testing with fixed placebo efficacy, asking how many experiments are needed in order to achieve a significance of 95%. In the next step, we take the probability distribution of the placebo efficacy into account, which to the best of our knowledge has not been done so far. Depending on the specifics, we show that in order to obtain identical significance, it may be necessary to perform twice as many experiments than in a setting where the placebo distribution is neglected. We proceed by considering more general probability distributions and close with comments on some erroneous assumptions on probability distributions which lead, for instance, to a trivial explanation of the fat tail.


2021 ◽  
Vol 12 ◽  
Author(s):  
Wei Zhang ◽  
Mengsi Xu ◽  
Juanjuan Wang ◽  
Shiyin Wang ◽  
Xinhua Wang ◽  
...  

Fat tail in sheep presents a valuable energy reserve that has historically facilitated adaptation to harsh environments. However, in modern intensive and semi-intensive sheep industry systems, breeds with leaner tails are more desirable. In the present study, RNA sequencing (RNA-Seq) was applied to determine the transcriptome profiles of tail fat tissues in two Chinese sheep breeds, fat-rumped Altay sheep and thin-tailed Xinjiang fine wool (XFW) sheep, with extreme fat tail phenotype difference. Then the differentially expressed genes (DEGs) and their sequence variations were further analyzed. In total, 21,527 genes were detected, among which 3,965 displayed significant expression variations in tail fat tissues of the two sheep breeds (P &lt; 0.05), including 707 upregulated and 3,258 downregulated genes. Gene Ontology (GO) analysis disclosed that 198 DEGs were related to fat metabolism. In Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, the majority of DEGs were significantly enriched in “adipocytokine signaling,” “PPAR signaling,” and “metabolic pathways” (P &lt; 0.05); moreover, some genes were involved in multiple pathways. Among the 198 DEGs, 22 genes were markedly up- or downregulated in tail fat tissue of Altay sheep, indicating that these genes might be closely related to the fat tail trait of this breed. A total of 41,724 and 42,193 SNPs were detected in the transcriptomic data of tail fat tissues obtained from Altay and XFW sheep, respectively. The distribution of seven SNPs in the coding regions of the 22 candidate genes was further investigated in populations of three sheep breeds with distinct tail phenotypes. In particular, the g.18167532T/C (Oar_v3.1) mutation of the ATP-binding cassette transporter A1 (ABCA1) gene and g.57036072G/T (Oar_v3.1) mutation of the solute carrier family 27 member 2 (SLC27A2) gene showed significantly different distributions and were closely associated with tail phenotype (P &lt; 0.05). The present study provides transcriptomic evidence explaining the differences in fat- and thin-tailed sheep breeds and reveals numerous DEGs and SNPs associated with tail phenotype. Our data provide a valuable theoretical basis for selection of lean-tailed sheep breeds.


Author(s):  
Maike Tormählen ◽  
Galiya Klinkova ◽  
Michael Grabinski

Statistical significance measures the reliability of a result obtained from a random experiment. We investigate the number of repetitions needed for a statistical result to have a certain significance. In the first step, we consider binomially distributed variables in the example of medication testing with fixed placebo efficacy, asking how many experiments are needed in order to achieve a significance of 95 %. In the next step, we take the probability distribution of the placebo efficacy into account, which to the best of our knowledge has not been done so far. Depending on the specifics, we show that in order to obtain identical significance, it may be necessary to perform twice as many experiments than in a setting where the placebo distribution is neglected. We proceed by considering more general probability distributions and close with comments on some erroneous assumptions on probability distributions which lead, for instance, to a trivial explanation of the fat tail.


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