4,831 research outputs found

    Schistosomiasis as a disease of stem cells

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    Schistosomiasis is a devastating parasitic disease caused by flatworms of the genus Schistosoma. The complex life cycles and developmental plasticity of these parasites have captured the attention of parsitologists for decades, yet little is known on the molecular level about the developmental underpinnings that have allowed these worms to thrive as obligate parasites. Here, we describe basic schistosome biology and highlight how understanding the functions of stem cells in these worms will transform our understanding of these parasites. Indeed, we propose that schistosomiasis is fundamentally as disease of stem cells. We hope this review will attract new interest in the basic developmental biology of these important organisms

    Radar signal categorization using a neural network

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    Neural networks were used to analyze a complex simulated radar environment which contains noisy radar pulses generated by many different emitters. The neural network used is an energy minimizing network (the BSB model) which forms energy minima - attractors in the network dynamical system - based on learned input data. The system first determines how many emitters are present (the deinterleaving problem). Pulses from individual simulated emitters give rise to separate stable attractors in the network. Once individual emitters are characterized, it is possible to make tentative identifications of them based on their observed parameters. As a test of this idea, a neural network was used to form a small data base that potentially could make emitter identifications

    A Template Analysis of Intimate Partner Violence Survivors’ Experiences of Animal Maltreatment: Implications for Safety Planning and Intervention

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    This study explores the intersection of intimate partner violence (IPV) and animal cruelty in an ethnically diverse sample of 103 pet-owning IPV survivors recruited from community-based domestic violence programs. Template analysis revealed five themes: (a) Animal Maltreatment by Partner as a Tactic of Coercive Power and Control, (b) Animal Maltreatment by Partner as Discipline or Punishment of Pet, (c) Animal Maltreatment by Children, (d) Emotional and Psychological Impact of Animal Maltreatment Exposure, and (e) Pets as an Obstacle to Effective Safety Planning. Results demonstrate the potential impact of animal maltreatment exposure on women and child IPV survivors’ health and safety

    Genetic characterization of influenza A(H3N2) viruses circulating in coastal Kenya, 2009-2017

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    Background Influenza viruses evolve rapidly and undergo immune driven selection, especially in the hemagglutinin (HA) protein. We report amino acid changes affecting antigenic epitopes and receptor‐binding sites of A(H3N2) viruses circulating in Kilifi, Kenya, from 2009 to 2017. Methods Next‐generation sequencing (NGS) was used to generate A(H3N2) virus genomic data from influenza‐positive specimens collected from hospital admissions and health facility outpatients presenting with acute respiratory illness to health facilities within the Kilifi Health and Demographic Surveillance System. Full‐length HA sequences were utilized to characterize A(H3N2) virus genetic and antigenic changes. Results From 186 (90 inpatient and 96 outpatient) influenza A virus‐positive specimens processed, 101 A(H3N2) virus whole genomes were obtained. Among viruses identified in inpatient specimens from 2009 to 2015, divergence of circulating A(H3N2) viruses from the vaccine strains A/Perth/16/2009, A/Texas/50/2012, and A/Switzerland/9715293/2013 formed 6 genetic clades (A/Victoria/208/2009‐like, 3B, 3C, 3C.2a, 4, and 7). Among viruses identified in outpatient specimens from 2015 to 2017, divergence of circulating A(H3N2) viruses from vaccine strain A/Hong Kong/4801/2014 formed clade 3C.2a, subclades 3C.2a2 and 3C.2a3, and subgroup 3C.2a1b. Several amino acid substitutions were associated with the continued genetic evolution of A(H3N2) strains in circulation. Conclusions Our results suggest continuing evolution of currently circulating A(H3N2) viruses in Kilifi, coastal Kenya and suggest the need for continuous genetic and antigenic viral surveillance of circulating seasonal influenza viruses with broad geographic representation to facilitate prompt and efficient selection of influenza strains for inclusion in future influenza vaccines

    A code of conduct is imperative for ocean carbon dioxide removal research

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Loomis, R., Cooley, S. R., Collins, J. R., Engler, S., & Suatoni, L. A code of conduct is imperative for ocean carbon dioxide removal research. Frontiers in Marine Science, 9, (2022): 872800, https://doi.org/10.3389/fmars.2022.872800.As the impacts of rising temperatures mount and the global transition to clean energy advances only gradually, scientists and policymakers are looking towards carbon dioxide removal (CDR) methods to prevent the worst impacts of climate change. Attention has increasingly focused on ocean CDR techniques, which enhance or restore marine systems to sequester carbon. Ocean CDR research presents the risk of uncertain impacts to human and environmental welfare, yet there are no domestic regulations aimed at ensuring the safety and efficacy of this research. A code of conduct that establishes principles of responsible research, fairness, and equity is needed in this field. This article presents fifteen key components of an ocean CDR research code of conduct.JC acknowledges funding support from Bezos Earth Fund

    The great caller ID debate

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    Age and Growth of King Mackerel, \u3cem\u3eScomberomorus cavalla\u3c/em\u3e, from the Atlantic Coast of the United States

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    Whole sagittae from 683 and sectioned sagittae from 773 adult (age\u3e 0 ; 437-1.310 mm FL), and lapilli from 29 larval (2-7 mm SL) and 69 young-of-the-year (79-320 mm FL) king mackerel, were examined. All fish were from waters off the Atlantic coast of the southeastern United States (Cape Canaveral, Florida to Cape Fear. North Carolina). Back-calculated lengths at ages and von Bertalanffy growth equations were calculated from both whole and sectioned sagittae. Ages determined from sectioned sagittae were significantly greater than ages determined from whole sagittae, and the magnitude of the difference increased with age (from sections). Rings on sectioned sagittae are considered to be true annual increments, forming during June-September. There was no clear pattern to ring formation on whole otoliths. The oldest fish examined was age 21. The daily nature of rings on lapilli of age 0 king mackerel was not validated, but if the marks are formed daily they suggest growth rates of approximately 0.47 mm/d for early larvae and 2.9 mm/d for fish 1-3 months of age

    Population growth, movements, and status of the Nushagak Peninsula Caribou Herd following reintroduction, 1988 - 2000

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    Barren ground caribou (Rangifer tarandus) were reintroduced to the Nushagak Peninsula, Alaska in February of 1988 after an absence of more than 100 years. Since reintroduction, herd growth and population dynamics have been monitored closely. At this time, there has been no significant dispersal from the herds' core range. The Nushagak Peninsula Caribou Herd (NPCH) grew rapidly from 146 reintroduced individuals to over 1000 in 13 years. Dramatic mean annual growth during the first 6 years (1988-1994) of 38% (r = 0.32) can be attributed to the high percentage of females in the initial reintroduction, high calf production and survival, exceptional range conditions, few predators, and no hunting. However, the populations' exceptional growth (peak counts of 1400) slowed and stabilized between 1996¬1998 and then decreased between 1998 and 2000. Size, body condition and weights of calves captured in 2000 were significantly lower than those captured in 1995 and 1997. Although calf production also decreased from close to 100% (1990-1995) to about 91% (1996-2000), overall calf survival continued to be high. Legal harvest began in 1995, and harvest reports have accounted for approximately 3% of population mortality annually. Although brown bears (Ursus arctos) and wolves (Canis lupus) are present, the extent of predation is unknown. Mean home range of the NPCH was 674 km2 and group sizes were greatest during post-calving aggregation in July (mean = 127). Caribou population density on the Nushagak Peninsula reached approximately 1.2 caribou/km2 in 1997 before declining to about 1.0 caribou/km2. A range survey in 1994 noted only trace utilization of lichens on the Nushagak Peninsula by caribou. A subsequent survey in 1999 found moderate to severe utilization in 46% of plots, suggesting the reintroduced herd was beginning to alter range condition. Between 1997 and 2000, both calf production and condition of 10-month-old calves declined. Calving has also been delayed in recent years. However, we suspect the reduced herd growth can be attributed to increasing hunting pressure and some dispersal of caribou from the Peninsula, not reduced range condition
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