Genomic structure in a global collection of domesticated sheep reveals a history of artificial selection for horn loss and traits relating to pigmentation, reproduction, and body size.
Branching processes are models used to describe populations that reproduce and die over time. In the classical setting, an individual's reproductive capacity remains constant throughout its lifetime. However, in real-world situations, reproductive capacity typically undergoes ageing - that is, after reaching a peak, it decreases over time. In this work, we study the influence of ageing on the behaviour of the process and how modifying its parameters, along with reproduction rates, affects the destiny of the process.
Surround sound systems commonly distribute loudspeakers along standardized layouts for multichannel audio reproduction. However in less controlled environments, practical layouts vary in loudspeaker quantity, placement, and listening locations / areas. Deviations from standard layouts introduce sound-field errors that degrade acoustic timbre, imaging, and clarity of audio content reproduction. This work introduces both Bayesian loudspeaker normalization and content panning optimization methods for sound-field correction. Conjugate prior distributions over loudspeaker-listener directions update estimated layouts for non-stationary listening locations; digital filters adapt loudspeaker acoustic responses to a common reference target at the estimated listening area without acoustic measurements. Frequency-domain panning coefficients are then optimized via sensitivity / efficiency objectives subject to spatial, electrical, and acoustic domain constraints; normalized and panned loudspeakers form virtual loudspeakers in standardized layouts for accurate multichannel reproduction. Experiments investigate robustness of Bayesian adaptation, and panning optimizations in practical applications.
We propose a novel approach to approximate the basic reproduction number $R_0$ as spectral radius of the Next-Generation Operator in time-periodic population models by characterizing the latter via evolution semigroups. Once birth/infection and transition operators are identified, we discretize them via either Fourier or Chebyshev collocation methods. Then $R_0$ is obtained by solving a generalized matrix eigenvalue problem. The order of convergence of the approximating reproduction numbers to the true one is shown to depend on the regularity of the model coefficients, and spectral accuracy is proved. We validate the theoretical results by discussing applications to epidemiology, viz. a large-size multi-group epidemic model with periodic contact rates, and a vector-borne disease model with seasonal vector recruitment. We illustrate how the method facilitates implementation compared to existing approaches and how it can be easily adapted to also compute type-reproduction numbers.
The occurrence of in-stent restenosis following percutaneous coronary intervention highlights the need for the creation of computational tools that can extract pathophysiological insights and optimize interventional procedures on a patient-specific basis. In light of this, a comprehensive framework encompassing multiple physical phenomena is introduced in this work. This framework effectively captures the intricate interplay of chemical, mechanical, and biological factors. In addition, computational approaches for the extraction of hemodynamic indicators that modulate the severity of the restenotic process are devised. Thus, this marks a significant stride towards facilitating computer-assisted clinical methodologies.
We consider a stochastic epidemic model with sideward contact tracing. We assume that infection is driven by interactions within mixing events (gatherings of two or more individuals). Once an infective is diagnosed, each individual who was infected at the same event as the diagnosed individual is contact traced with some given probability. Assuming few initial infectives in a large population, the early phase of the epidemic is approximated by a branching process with sibling dependencies. To address the challenges given by the dependencies, we consider sibling groups (individuals who become infected at the same event) as macro-individuals and define a macro-branching process. This allows us to derive an expression for the effective macro-reproduction number which corresponds to the effective individual reproduction number and represents a threshold for the behaviour of the epidemic. Through numerical examples, we show how the reproduction number varies with the distribution of the mixing event size, the mean size, the rate of diagnosis and the tracing probability.
In the early stage of an infectious disease outbreak, public health strategies tend to gravitate towards non-pharmaceutical interventions (NPIs) given the time required to develop targeted treatments and vaccines. One of the most common NPIs is Test-Trace-Isolate (TTI). One of the factors determining the effectiveness of TTI is the ability to identify contacts of infected individuals. In this study, we propose a multi-layer temporal contact network to model transmission dynamics and assess the impact of different TTI implementations, using SARS-CoV-2 as a case study. The model was used to evaluate TTI effectiveness both in containing an outbreak and mitigating the impact of an epidemic. We estimated that a TTI strategy based on home isolation and testing of both primary and secondary contacts can contain outbreaks only when the reproduction number is up to 1.3, at which the epidemic prevention potential is 88.2% (95% CI: 87.9%-88.5%). On the other hand, for higher value of the reproduction number, TTI is estimated to noticeably mitigate disease burden but at high social costs (e.g., over a month in isolation/quarantine per person for reproduction numbers of 1.7 or higher). We estimated that strategies considering quarantine of contacts have a larger epidemic prevention potential than strategies that either avoid tracing contacts or require contacts to be tested before isolation. Combining TTI with other social distancing measures can improve the likelihood of successfully containing an outbreak but the estimated epidemic prevention potential remains lower than 50% for reproduction numbers higher than 2.1.
For a heterogeneous host population, the basic reproduction number of an infectious disease, $\cR_0$, is defined as the spectral radius of the next generation operator (NGO). The threshold properties of the basic reproduction number are typically established by imposing conditions that make $\cR_0$ an eigenvalue of the NGO associated with a positive eigenvector and a positive eigenfunctional (eigenvector of the dual of the NGO). More general results can be obtained by imposing conditions that associate $\cR_0$ just with a positive eigenfunctional. The next generation operator is conveniently expressed by a measure kernel or a Feller kernel which enables the use of analytic rather than functional analytic methods.
In this study, we explore how educational differences in demographic behavior – in particular, mating patterns and fertility – mediate the intergenerational reproduction of educational inequality in twelve European countries. Although this research interest itself is not new, we contribute to this debate by adopting a prospective approach and scaling it to include multiple countries and cohorts. To this end, we leverage a series of complementary datasets and the inferential method developed by Song and Mare (2015) and advanced by Skopek and Leopold (2020) to estimate the components of a stylized educational reproduction model. We then employ a simple decomposition analysis to quantify the contributions of different pathways to prospective educational reproduction rates across educational backgrounds and explore the differences across cohorts and countries. We report several findings. Most notably, (1) the intergenerational reproduction of educational inequality persists in all twelve countries and is barely offset by small (and declining) negative educational gradients in fertility, (2) educational differences in selection into partnership are small and do not account for much inequality, and (3) the role of assortative mating, where present, is ambiguous because it both reinforces inequality via its effects on resources within the family and offsets it via its effects on fertility.
* This article belongs to a special issue on “Changes in Educational Homogamy and Its Consequences”.
Urban groups. The city. Urban sociology, City population. Including children in cities, immigration
Studies of wealth and the family have provided important insights into how financial and legal institutions allow the long-term perpetuation of fortunes, such as inheritance and trust laws, as well as examining the role of family offices and philanthropy as practices that upper-class families use to preserve their wealth across generations. Such scholarship has noticed that a flip side of this is that the family, as a unit involved in the preservation of inter-generational wealth, can also be a site of conflict that ultimately destroys great fortunes. Focusing on life coaching as a growing therapeutic cultural form among the wealthy in Brazil, I expand on these important financial and legal practices to include an often-ignored gendered site of elite reproduction: processes of self-cultivation to accrue interiority currency, as practiced by wealthy parents (especially mothers) in the socialization of family heirs. In this article, I analyze the intersection of wealth, gender, and therapeutic cultures, as they contour sociability and social reproduction in Ipanema, a well-known Rio de Janeiro neighbourhood. I draw from the experience of Vera Ferreira de Oliveira, a Brazilian woman from a working-class family in Niteroi who married into a very wealthy Ipanema family in the early 2000s. Through Vera’s life coaching experience with Katia Coutinho, I investigate the material repercussions (imagined or real) of therapeutic projects designed to alter the inner linings of the self and affective dispositions and to shape elite family sociability. Resumen: Culturas terapéuticas en familias de élite en Brasil: 'Coaching' vital, socialidad y economía moral del privilegio Los estudios sobre la riqueza y la familia han aportado importantes conocimientos sobre cómo las instituciones financieras y jurídicas permiten la perpetuación de las fortunas a largo plazo, como las leyes de sucesión y fideicomiso, además de examinar el papel de las oficinas familiares y la filantropía como prácticas que las familias de clase alta utilizan para preservar su riqueza a través de generaciones. Estos estudios han observado que la otra cara de la moneda es que la familia, como unidad implicada en la preservación de la riqueza intergeneracional, también puede ser un lugar de conflicto que acaba destruyendo grandes fortunas. Centrándome en el coaching vital como forma cultural terapéutica creciente entre los ricos de Brasil, amplío estas importantes prácticas financieras y legales para incluir un lugar de reproducción de la élite a menudo ignorado: los procesos de autocultivo para acumular divisas de interioridad, practicados por progenitores ricos (especialmente las madres) en la socialización de los herederos familiares. En este artículo, analizo la intersección entre riqueza, género y culturas terapéuticas, tal y como conforman la sociabilidad y la reproducción social en Ipanema, un conocido barrio de Río de Janeiro. Me baso en la experiencia de Vera Ferreira de Oliveira, una brasileña de clase trabajadora de Niteroi que se casó con una acaudalada familia de Ipanema a principios de la década de 2000. A través de la experiencia de coaching vital de Vera con Katia Coutinho, investigo las repercusiones materiales (imaginarias o reales) de los proyectos terapéuticos diseñados para alterar los revestimientos internos del yo y las disposiciones afectivas, y para dar forma a la sociabilidad familiar de élite.
Selionova Marina, Gladkikh Marianna, Zharkova Ekaterina
et al.
The study determines the reliability, direction and strength of the relationship between the main components of the milk of Lacon sheep (n=96) and Saanen goats (n=134). It was found that the nature and direction of the relationship between MFF and other components of milk in goats and sheep were similar. Between MFF and TTP, casein, the content of fatty acids, both saturated (SFA, LCFA, STsFA) and unsaturated (MUFA, PUFA, SCFA), an average and high positive relationship was revealed. At the same time, it was more pronounced in sheep milk (r = 0.41 ... 0.97) than in goat milk (r = 0.38 ... 0.84). For goat and sheep milk, a high positive (r = 0.95 and 0.99), i.e. functional, relationship between the content of casein and TTP was revealed. No relationship has been established between the number of somatic cells (CSC) and other components in sheep milk and goat milk. Also, there was no relationship between the differential number of somatic cells (DKSK) and other indicators, with the exception of the number of somatic cells and lactose content, as in the milk of sheep and goats. The study was carried out within the framework of the complex project “Scientific and technological frontiers” of the strategic academic leadership program “Priority 2030” on the topic “Biotechnological methods of reproduction and genomic technologies in the selection of farm animals and the conservation of the gene pool of small in number breeds”.
MTNR1A and MTNR1B, two high-affinity MT membrane receptors found in mammals, mediate the activity of MT on the HPGA to regulate animal reproduction. Nevertheless, the expression patterns and function of the MTNR1A and MTNR1B genes in the HPTA of seasonal estrus sheep and perennial estrus sheep have not been elucidated. We studied the expression of MTNR1A and MTNR1B in the hypothalamic-pituitary-testicular axis (HPTA) of Tibetan sheep at different reproductive stages using histochemistry, enzyme linked immunosorbent assay (ELSIA), scanning electron microscopy, transmission electron microscopy, quantitative Real-time PCR (qRT-PCR), and Western blot (WB), and analyzed the relationship between their expression and reproductive hormone receptors. We also compared relevant characteristics between seasonal Tibetan sheep and non-seasonal Small Tail Han sheep in the same pastoral area. The results showed that MTNR1A and MTNR1B were expressed in all tissues of the Tibetan sheep HPTA, and both were co-expressed in the cytoplasm of epididymis basal and halo cells located at common sites of the epididymis basement membrane, forming an immune barrier. The qRT-PCR analysis showed that not only MTNR1A but also N-acetyltransferase (AANAT), hydroxyindole-oxygen- methyltransferase (HIOMT), androgen receptor (AR), and estrogen receptor α (ERα) mRNA expression was significantly upregulated in the testis and epididymis of Tibetan sheep during the breeding season, whereas no clear upregulation of these genes was observed in the tissues of Small Tail Han sheep. MTNR1A and MTNR1B are important regulators of the HPTA in sheep. MTNR1A mediates seasonal estrus regulation in Tibetan sheep. Both MTNR1A and MTNR1B may play important roles in formation of the blood-epididymal barrier. The results of this study should help advance research on the mechanism of reproductive regulation of the HPTA in male animals and provide reference data for improving the reproductive rate of seasonal breeding animals.
Jinhui Li, Mojeeb AL-Rahman EL-Nor Osman, Zhidong Teng
In this paper, a dynamical model of malaria transmission with vector-bias and timedependent controls is investigated. The controls include the RTS,S malaria vaccine, using insecticide-treated mosquito net, treatment of infectious human, and indoor spraying. For constant controls, the existence and stability of equilibrium, as well as the existence of backward bifurcation, are obtained. The sensitivity analysis quantifies the impact of parameters and controls on the basic reproduction number. For time-dependent controls, by using the Pontryagin’s maximum principle the existence and expression of optimal controls are established. As an application of the model and control strategies, the malaria transmission and controls in Democratic Republic of Congo are discussed. To be specific, we simulate the reported cases of Democratic Republic of Congo by World Health Organization and predict the trends. Cost-effectiveness analysis and numerical simulations show that combining all controls can minimize the number of infected humans to the full extent, using insecticide-treated mosquito net is the most cost-effectiveness strategy, combining RTS,S malaria vaccine with using insecticide-treated mosquito net and treatment of infectious human is also cost-effective among all the strategies with good effect.
Water level rise is considered an environmental filter for the growth and reproduction of aquatic plants in lakes. Some emergent macrophytes can form floating mats, enabling them to escape from the negative effects of deep water. However, an understanding of which species can be uprooted and form floating mats easily and what factors affect these tendencies remains greatly elusive. We conducted an experiment to determine whether the monodominance of <i>Zizania latifolia</i> in the emergent vegetation community in Lake Erhai was related to its floating mat formation ability and to try to find the reasons for its floating mat formation ability during the continuous increase in water level over the past few decades. Our results showed that both the frequency and biomass proportion of <i>Z. latifolia</i> were greater among the plants on the floating mats. Furthermore, <i>Z. latifolia</i> was more likely to be uprooted than the other three previously dominant emergent species due to its smaller angle between the plant and the horizontal plane, rather than the root:shoot or volume:mass ratios. The dominance of <i>Z. latifolia</i> in the emergent community in Lake Erhai is due to its easier ability to become uprooted, allowing it to outperform other emergent species and become the single dominant emergent species under the environmental filter of deep water. The ability to uproot and form floating mats may be a competitive survival strategy for emergent species under the conditions of continuous significant water level rise.
Seung-Ju Cheon, Md. Mizanur Rahman, Ji-A Lee
et al.
Alien invasive species are posing conservation challenges worldwide. Pet trade, one of the many ways, is worsening the situation. Especially, pet turtles have been released into nature due to their longer life span and peoples’ religious and traditional beliefs. In addition, unwanted and undesired pets are also released. While information on the successful local establishment and subsequent dispersal into new habitats is required to designate an invasive and ecosystem-disturbing species, alien freshwater turtle nests have always been hard to find and identify in nature. Because one should identify nests by the eggs, which do not always guide properly, as adults abandon the sites quickly. We thought the recent advancement in DNA technology may help improve the situation. We studied Pseudemys peninsularis, one of the most traded freshwater turtle pet species, which has already been reported from a wide range of wild areas in South Korea. Yet, it is not designated as ecosystem-disturbing species due to a lack of adequate information on their local reproduction and establishment. We conducted surveys and found two nests in Jeonpyeongje Neighborhood Park, Maewol-dong, Seo-gu, Gwangju. We developed the methodology for extracting DNA from the eggshells and successfully identified the nests by phylogenetic analysis and verified through egg characteristics and morphological features of artificially hatched juveniles. This was the first successful initiative to extract DNA from freshwater turtle eggshells. We believe it will help future researchers identify the alien invasive turtle nests and develop their control and management policies. In addition, our study also included comparative descriptions and schematic diagrams of the eggs of eight freshwater turtles, including a native and three ecosystem-disturbing species, from South Korea. We urged an immediate designation of P. peninsularis as an ecosystem-disturbing species considering its local establishment, distribution range, and potential negative impact on native ecosystems.
To investigate the combined effects of drug resistance, seasonality and vector-bias, we formulate a periodic two-strain reaction-diffusion model. It is a competitive system for resistant and sensitive strains, but the single-strain subsystem is cooperative. We derive the basic reproduction number $\mathcal {R}_i$ and the invasion reproduction number $\mathcal {\hat{R}}_i$ for strain $i~(i=1,2)$, and establish the transmission dynamics in terms of these four quantities. More precisely, (i) if $\mathcal {R}_1<1$ and $\mathcal{R}_2<1$, then the disease is extinct; (ii) if $\mathcal {R}_1>1>\mathcal{R}_2$ ($\mathcal {R}_2>1>\mathcal{R}_1$), then the sensitive (resistant) strains are persistent, while the resistant (sensitive) strains die out; (iii) if $\mathcal {R}_i>1$ and $\mathcal {\hat{R}}_i>1~(i=1,2)$, then two strains are coexistent and periodic oscillation phenomenon is observed. We also study the asymptotic behavior of the basic reproduction number with respect to small and large diffusion coefficients. Numerically, we demonstrate the phenomena of coexistence and competitive exclusion for two strains and explore the influences of seasonality and vector-bias on disease spreading.
Abstract Background This study aimed to evaluate the influences of SARS-CoV-2 infection on semen parameters and investigate the impact of the infection on in vitro fertilization (IVF) outcomes. Methods This retrospective study enrolled couples undergoing IVF cycles between May 2020 and February 2021 at Tongji Hospital, Wuhan. Baseline characteristics were matched using propensity score matching. Participants were categorized into an unexposed group (SARS-COV-2 negative) and exposed group (SARS-COV-2 positive) based on a history of SARS-CoV-2 infection, and the populations were 148 and 50 after matching, respectively. IVF data were compared between the matched cohorts. Moreover, semen parameters were compared before and after infection among the infected males. The main measures were semen parameters and IVF outcomes, including laboratory and clinical outcomes. Results Generally, the concentration and motility of sperm did not significantly differ before and after infection. Infected males seemed to have fewer sperm with normal morphology, while all values were above the limits. Notably, the blastocyst formation rate and available blastocyst rate in the exposed group were lower than those in the control group, despite similar mature oocytes rates, normal fertilization rates, cleavage rates, and high-quality embryo rates. Moreover, no significant differences were exhibited between the matched cohorts regarding the implantation rate, biochemical pregnancy rate, clinical pregnancy rate, or early miscarriage rate. Conclusions The results of this retrospective cohort study suggested that the semen quality and the chance of pregnancy in terms of IVF outcomes were comparable between the males with a history of SARS-CoV-2 infection and controls, although a decreased blastocyst formation rate and available blastocyst rate was observed in the exposed group, which needs to be reinforced by a multicenter long-term investigation with a larger sample size.