Bounding Seed Loss from Isolated Habitat Patches.

Dispersal of propagules (seeds, spores) from a geographically isolated habitat into an uninhabitable matrix can play a decisive role in driving population dynamics. ODE and integrodifference models of these dynamics commonly feature a "dispersal success" parameter representing the average proportion of dispersing propagules that remain in viable habitat. While dispersal success can be estimated by empirical measurements or by integration of dispersal kernels, one may lack resources for fieldwork or details on dispersal kernels for numerical computation.

Processes for the 3D Printing of Hydrodynamic Flow-Focusing Devices.

Flow focusing is an important hydrodynamic technique for cytometric analysis, enabling the rapid study of cellular samples to identify a variety of biological processes. To date, the majority of flow-focusing devices are fabricated using conventional photolithography or flame processing of glass capillaries. This article presents a suite of low-cost, millifluidic, flow-focusing devices that were fabricated using a desktop sterolithgraphy (SLA) 3D printer.

Nitrogen-Induced Hysteresis in Grassland Biodiversity: A Theoretical Test of Litter-Mediated Mechanisms.

AbstractThe global rise in anthropogenic reactive nitrogen and the negative impacts of N deposition on terrestrial plant diversity are well documented. The R* theory of resource competition predicts reversible decreases in plant diversity in response to N loading. However, empirical evidence for the reversibility of N-induced biodiversity loss is mixed.

Understanding the Sexual and Reproductive Health Experiences of Refugee and Host Community Adolescents and Youth in Rwanda During COVID-19: Needs, Barriers, and Opportunities.

Background: COVID-19 has exacerbated the sexual and reproductive health (SRH) needs of those affected by humanitarian emergencies, particularly affecting adolescents and youth, whose needs are often neglected during crises. In Rwanda, the situation for refugees in Mahama Refugee Camp has worsened, as COVID-19 lockdown measures have increased needs while restricting access to basic services. Few assessments have been conducted on the SRH needs of refugees in Mahama camp, including adolescents and youth, since COVID-19.

Hepatitis C virus testing perspectives among primary care physicians in four large primary care settings.

Background: In 1998, the Centers for Disease Control and Prevention (CDC) published Recommendations for Prevention and Control of Hepatitis C Virus (HCV) Infection and HCV-Related Chronic Disease, recommending HCV testing for populations most likely to be infected with HCV. However, the implementation of risk-based screening has not been widely adopted in health care settings, and 45% to 85% of infected U.S.

Interplay between structure-specific endonucleases for crossover control during Caenorhabditis elegans meiosis.

The number and distribution of crossover events are tightly regulated at prophase of meiosis I. The resolution of Holliday junctions by structure-specific endonucleases, including MUS-81, SLX-1, XPF-1 and GEN-1, is one of the main mechanisms proposed for crossover formation. However, how these nucleases coordinately resolve Holliday junctions is still unclear.

Speed of kill efficacy and efficacy of flavored spinosad tablets administered orally to cats in a simulated home environment for the treatment and prevention of cat flea (Ctenocephalides felis) infestations.

The efficacy of spinosad against adult fleas (Ctenocephalides felis) on cats was evaluated in two separate controlled, blinded studies-one to determine flea knockdown and speed of flea kill (SOFK) on experimentally infested cats, another to assess the ability of spinosad to prevent flea infestations in a simulated home environment (SHE) study design. In each study, pre-treatment live flea counts were used as a blocking factor to randomize cats to treatment, and treated in the fed state, with flavored tablets containing either no active ingredient (control) or spinosad (50-100mg/kg in the SOFK study; 50-75 mg/kg body weight in the SHE study). In the SOFK study, 6 cats per group were infested with unfed adult fleas on Day -1.

SLX-1 is required for maintaining genomic integrity and promoting meiotic noncrossovers in the Caenorhabditis elegans germline.

Although the SLX4 complex, which includes structure-specific nucleases such as XPF, MUS81, and SLX1, plays important roles in the repair of several kinds of DNA damage, the function of SLX1 in the germline remains unknown. Here we characterized the endonuclease activities of the Caenorhabditis elegans SLX-1-HIM-18/SLX-4 complex co-purified from human 293T cells and determined SLX-1 germline function via analysis of slx-1(tm2644) mutants. SLX-1 shows a HIM-18/SLX-4-dependent endonuclease activity toward replication forks, 5'-flaps, and Holliday junctions.

A comparison of developmental social-pragmatic and naturalistic behavioral interventions on language use and social engagement in children with autism.

Purpose: Developmental social-pragmatic and naturalistic behavioral interventions share a number of features, but they differ in their use of facilitative strategies and direct elicitation of child language. In this study, the authors investigated whether these approaches produce different language and social outcomes in young children with autism.

Method: The authors used an ABACAD design to compare the effects of a developmental social-pragmatic, naturalistic behavioral, and combined intervention on language type and function and social engagement in 5 children with autism.

Increased rates of depressed mood in mothers of children with ASD associated with the presence of the broader autism phenotype.

This study examined the relationship between the broader autism phenotype (BAP) and depressed mood in mothers of children with and without autism spectrum disorders (ASD). One hundred and sixty-five mothers (71 with an ASD child and 94 with a non-ASD child) completed a survey of child autism severity (ASD mothers only), parenting stress, BAP, and depression. Mothers of children with ASD reported greater depressed mood, higher parenting stress, and more characteristics associated with the BAP than mothers of children without ASD.

Chronic physical health conditions and disability among Canadian school-aged children: a national profile.

Objective: The objective of this study was to provide a national health and disability profile of Canadian school-aged children based on the World Health Organization's definitions of health condition and disability that would facilitate international comparisons of child health data.

Methods: Data were used from the National Longitudinal Survey of Children and Youth, a 1994 - 95 population-based sample of 22 831 children.

Findings: An estimated total of 30.