Genomic insights into key genes and QTLs involved in cattle reproduction.

From an economic standpoint, reproductive characteristics are fundamental for sustainable production, particularly for monotocous livestock like cattle. A longer inter-calving interval is indicative of low reproductive capacity. This issue changes the dynamics of current and future lactations since it necessitates more inseminations, veterinary care, and hormone interventions. Various reproductive phenotypes, including ovulation, mating, fertility, pregnancy, embryonic growth, and calving-related traits, are observed in dairy cattle, and these traits have been associated with several QTLs. Calving ease, age at puberty, scrotal circumference, and inseminations per conception have been associated with 4437, 10623, 10498, and 2476 Quantitative Trait Loci (QTLs), respectively. This data offers valuable insights into enhancing and comprehending reproductive traits in livestock breeding. Studying QTLs associated with reproductive traits has far-reaching implications across various fields, from agriculture and animal husbandry to human health, evolutionary biology, and conservation. It provides the foundation for informed breeding practices, advances in biotechnology, and a deeper understanding of the genetic underpinnings of reproduction.

Deciphering climate resilience in Indian cattle breeds by selection signature analyses.

The signature of selection is a crucial concept in evolutionary biology that refers to the pattern of genetic variation which arises in a population due to natural selection. In the context of climate adaptation, the signature of selection can reveal the genetic basis of adaptive traits that enable organisms to survive and thrive in changing environmental conditions. Breeds living in diverse agroecological zones exhibit genetic "footprints" within their genomes that mirror the influence of climate-induced selective pressures, subsequently impacting phenotypic variance. It is assumed that the genomes of animals residing in these regions have been altered through selection for various climatic adaptations. These regions are known as signatures of selection and can be identified using various summary statistics. We examined genotypic data from eight different cattle breeds (Gir, Hariana, Kankrej, Nelore, Ongole, Red Sindhi, Sahiwal, and Tharparkar) that are adapted to diverse regional climates. To identify selection signature regions in this investigation, we used four intra-population statistics: Tajima's D, CLR, iHS, and ROH. In this study, we utilized Bovine 50 K chip data and four genome scan techniques to assess the genetic regions of positive selection for high-temperature adaptation. We have also performed a genome-wide investigation of genetic diversity, inbreeding, and effective population size in our target dataset. We identified potential regions for selection that are likely to be caused by adverse climatic conditions. We observed many adaptation genes in several potential selection signature areas. These include genes like HSPB2, HSPB3, HSP20, HSP90AB1, HSF4, HSPA1B, CLPB, GAP43, MITF, and MCHR1 which have been reported in the cattle populations that live in varied climatic regions. The findings demonstrated that genes involved in disease resistance and thermotolerance were subjected to intense selection. The findings have implications for marker-assisted breeding, understanding the genetic landscape of climate-induced adaptation, putting breeding and conservation programs into action.

Unique footprints of balancing selection in bovine genome.

Balancing selection is the process of selection that preserves various alleles within a population. Studying the areas undergoing balancing selection is essential, because it preserves genetic diversity in a population. Finding genes that exhibit signs of balancing selection during the domestication of cattle is the goal of this study. To identify regions where polymorphism has persisted in the cattle population for millions of years, we examined the genome of cattle. In this study, we used bovine SNP 50 k data to conduct a detailed genome-wide assessment of selection signatures for balancing selection. We have included the genotyped data from 427 animals, including five taurines, two crossbreds, and eight Indian cattle breeds. For this study, we employed Tajima's D approach to identify signature regions undergoing balancing selection. Using the NCBI database, PANTHER 17.0, and CattleQTL database, the annotation was carried out after finding the relevant areas under balancing selection. The number of genomic regions undergoing balancing selection in Ayrshire, Brown-Swiss, Frieswal, Gir, Guernsey, Hariana, Holstein Friesian, Jersey, Kankrej, Nelore, Ongole, Red Sindhi, Sahiwal, Tharparkar, and Vrindavani was 11, 13, 13, 19, 18, 11, 17, 14, 14, 12, 10, 12, 13, 13, and 11, respectively. We have observed multiple immune system-related genes going through balancing selection, including KIT, NFATC2, GBP4, LRRC32, SYT7, RAG1, RAG2, LOC513659, and ZBTB17. In our study, we found that the majority of the immune-related genes and a few genes associated with growth, reproduction, production, and adaptation are undergoing balancing selection.

Landmarks in the history of selective sweeps.

Half a century ago, a seminal article on the hitchhiking effect by Smith and Haigh inaugurated the concept of the selection signature. Selective sweeps are characterised by the rapid spread of an advantageous genetic variant through a population and hence play an important role in shaping evolution and research on genetic diversity. The process by which a beneficial allele arises and becomes fixed in a population, leading to a increase in the frequency of other linked alleles, is known as genetic hitchhiking or genetic draft. Kimura's neutral theory and hitchhiking theory are complementary, with Kimura's neutral evolution as the 'null model' and positive selection as the 'signal'. Both are widely accepted in evolution, especially with genomics enabling precise measurements. Significant advances in genomic technologies, such as next-generation sequencing, high-density SNP arrays and powerful bioinformatics tools, have made it possible to systematically investigate selection signatures in a variety of species. Although the history of selection signatures is relatively recent, progress has been made in the last two decades, owing to the increasing availability of large-scale genomic data and the development of computational methods. In this review, we embark on a journey through the history of research on selective sweeps, ranging from early theoretical work to recent empirical studies that utilise genomic data.

Corrigendum: QUaRTM: A Quadcopter with Unactuated Rotor Tilting Mechanism capable of faster, more agile, and more efficient flight.

[This corrects the article DOI: 10.3389/frobt.2022.1033715.].

QUaRTM: A Quadcopter with Unactuated Rotor Tilting Mechanism capable of faster, more agile, and more efficient flight.

We present QUaRTM - a novel quadcopter design capable of tilting the propellers into the forward flight direction, which reduces the drag area and therefore allows for faster, more agile, and more efficient flight. The vehicle can morph between two configurations in mid-air, including the untilted configuration and the tilted configuration. The vehicle in the untilted configuration has a higher pitch torque capacity and a smaller vertical dimension. The vehicle in the tilted configuration has a lower drag area, leading to a higher top speed, higher agility at high speed, and better flight efficiency. The morphing is accomplished without any additional actuators beyond the four motors of a quadcopter. The rigid connections between the quadcopter frame and the quadcopter arms are replaced with sprung hinges. This allows the propellers to be tilted when high thrusts are produced, and recover to the untilted configuration when the thrusts are brought low. The effectiveness of such a vehicle is demonstrated by running experiments on a prototype vehicle with a shape similar to a regular quadcopter. Through the use of tilting, the vehicle is shown to have a 12.5% higher maximum speed, better high-speed agility as the maximum crash-free cruise speed increased by 7.5%, and a better flight efficiency as the power consumption has dropped by more than 20% in the speed range of 15-20 m s-1.

Blood Pressure Estimation Based on Pulse Arrival Time and Heart Rate : A Correlation Analysis for Critically Ill Patients.

Arterial blood pressure (ABP) is a vital hemodynamic signal to be monitored in general population- especially in critically ill patients. Pulse arrival time (PAT) has been widely used for the noninvasive measurement of systolic blood pressure (SBP) and diastolic blood pressure (DBP) and has shown excellent results for a healthy person as compared to the existing gold standard methods. In this study, we have used correlation analysis to study the feasibility of using PAT and heart rate (HR) for noninvasive BP (SBP and DBP) measurement for critically ill subjects. Physiological signals used for this study were collected from the MIMIC-II database of Physionet. Initially, we conducted a correlation analysis and then tried to estimate BP using linear regression. We found that the BP correlation with HR is more as compared with PAT. However, these correlations are not consistent. We have also found that PAT and HR can track the BP change as long as the correlation coefficient lies between ±0.7 and ±1. When the correlation falls below, this noninvasive BP estimation using PAT and HR needs to be revisited and improved for clinical applicability.

Modeling of cardiovascular circulation for the early detection of coronary arterial blockage.

Coronary arteries are responsible for maintaining blood supply to the heart. When these arteries get blocked due to plaque deposition, the corresponding pathological condition is referred to as coronary artery disease. This disease develops gradually over the years and consequently, the function of the heart deteriorates, leading to a heart attack in many cases. As the symptoms manifest themselves only when it has become severe, detection of the disease often gets delayed. In order to detect it early and take preventive action, this work is aimed at detecting the arterial blockage in its early stage via cardiovascular modeling. To achieve this, the cardiovascular circulation has been modeled as a sixth order nonlinear system. Blood circulation in a body is viewed as an electrical system using the pressure-voltage analogy. In this case, the heart is considered as a self-excited generator. The rest of the body tissues form a systemic load. In the models reported in the literature, coronary circulation has been assumed to be a part of the systemic load. However, this circulation path has its own importance as it is responsible for the blood supply to the heart. Therefore, in our work, the coronary path is separated out from the rest of the body tissues. This enables us to explicitly model the coronary arterial resistance and thereby helps us to detect coronary arterial blockage condition by estimating this parameter from blood pressure measurements. Increase in the coronary resistance is found to reduce the left ventricular ejection fraction; this information can therefore be used as an index for coronary arterial blockage. It has been shown that the systolic function of the heart deteriorates when the resistance of the coronary path increases beyond a critical value; the situation can be related to a severe blockage condition. The model has been tested on a chosen sample of 20 subjects suffering from coronary artery disease and the results are found to be quite promising.