RESUMO
The plant immune system relies on the perception of molecules that signal the presence of a microbe threat. This triggers signal transduction that mediates a range of cellular responses via a collection of molecular machinery including receptors, small molecules, and enzymes. One response to pathogen perception is the restriction of cell-to-cell communication by plasmodesmal closure. We previously found that while chitin and flg22 trigger specialized immune signaling cascades in the plasmodesmal plasma membrane, both execute plasmodesmal closure via callose synthesis at the plasmodesmata. Therefore, the signaling pathways ultimately converge at or upstream of callose synthesis. To establish the hierarchy of signaling at plasmodesmata and characterize points of convergence in microbe elicitor-triggered signaling, we profiled the dependence of plasmodesmal responses triggered by different elicitors on a range of plasmodesmal signaling machinery. We identified that, like chitin, flg22 signals via RESPIRATORY BURST OXIDASE HOMOLOGUE D (RBOHD) to induce plasmodesmal closure. Further, we found that PLASMODESMATA-LOCATED PROTEIN 1 (PDLP1), PDLP5, and CALLOSE SYNTHASE 1 (CALS1) are common to microbe- and salicylic acid (SA)-triggered responses, identifying PDLPs as a candidate signaling nexus. To understand how PDLPs relay a signal to CALS1, we screened for PDLP5 interactors and found NON-RACE SPECIFIC DISEASE RESISTANCE/HIN1 HAIRPIN-INDUCED-LIKE protein 3 (NHL3), which is also required for chitin-, flg22- and SA-triggered plasmodesmal responses and PDLP-mediated activation of callose synthesis. We conclude that a PDLP-NHL3 complex acts as an integrating node of plasmodesmal signaling cascades, transmitting multiple immune signals to activate CALS1 and plasmodesmata closure.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Plasmodesmos/metabolismo , Transdução de Sinais , Ácido Salicílico/metabolismo , Quitina/metabolismoRESUMO
In plants, plasmodesmata establish cytoplasmic continuity between cells to allow for communication and resource exchange across the cell wall. While plant pathogens use plasmodesmata as a pathway for both molecular and physical invasion, the benefits of molecular invasion (cell-to-cell movement of pathogen effectors) are poorly understood. To establish a methodology for identification and characterization of the cell-to-cell mobility of effectors, we performed a quantitative live imaging-based screen of candidate effectors of the fungal pathogen Colletotrichum higginsianum. We predicted C. higginsianum effectors by their expression profiles, the presence of a secretion signal, and their predicted and in planta localization when fused to green fluorescent protein. We assayed for cell-to-cell mobility of nucleocytosolic effectors and identified 14 that are cell-to-cell mobile. We identified that three of these effectors are "hypermobile," showing cell-to-cell mobility greater than expected for a protein of that size. To explore the mechanism of hypermobility, we chose two hypermobile effectors and measured their impact on plasmodesmata function and found that even though they show no direct association with plasmodesmata, each increases the transport capacity of plasmodesmata. Thus, our methods for quantitative analysis of cell-to-cell mobility of candidate microbe-derived effectors, or any suite of host proteins, can identify cell-to-cell hypermobility and offer greater understanding of how proteins affect plasmodesmal function and intercellular connectivity. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
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Plantas , Plasmodesmos , Plasmodesmos/metabolismo , Plantas/metabolismo , Citoplasma , Citosol , Parede CelularRESUMO
The long-term behaviors of biochemical systems are often described by their steady states. Deriving these states directly for complex networks arising from real-world applications, however, is often challenging. Recent work has consequently focused on network-based approaches. Specifically, biochemical reaction networks are transformed into weakly reversible and deficiency zero generalized networks, which allows the derivation of their analytic steady states. Identifying this transformation, however, can be challenging for large and complex networks. In this paper, we address this difficulty by breaking the complex network into smaller independent subnetworks and then transforming the subnetworks to derive the analytic steady states of each subnetwork. We show that stitching these solutions together leads to the analytic steady states of the original network. To facilitate this process, we develop a user-friendly and publicly available package, COMPILES (COMPutIng anaLytic stEady States). With COMPILES, we can easily test the presence of bistability of a CRISPRi toggle switch model, which was previously investigated via tremendous number of numerical simulations and within a limited range of parameters. Furthermore, COMPILES can be used to identify absolute concentration robustness (ACR), the property of a system that maintains the concentration of particular species at a steady state regardless of any initial concentrations. Specifically, our approach completely identifies all the species with and without ACR in a complex insulin model. Our method provides an effective approach to analyzing and understanding complex biochemical systems.
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Modelos Biológicos , Modelos QuímicosRESUMO
People's emotional states are influenced not just by events occurring in the present but also by how events have unfolded in the past and how they are likely to unfold in the future. To what extent do young children understand the ways in which past events can affect current emotions even if they are no longer ongoing? In the current study, we explored children's ability to understand how others feel at the cessation of events-as events change from being present to being past. We asked 97 4- to 6-year-olds (40.2% female) and 35 adults (54.3% female) to judge how characters felt once particular types of events had ended relative to how they felt during these events. We found that from age 4, children judged (as adults do) that the character would feel positive at the cessation of negative events-what we refer to as temporal relief. This understanding of relief occurs earlier than has been shown in previous research. However, children were less likely than adults to judge others as feeling sad at the cessation of positive events-what we refer to as temporal disappointment. Overall, our findings suggest that children not only understand that the cessation of events can affect others' emotions but also recognize that people feel differently following the cessation of positive, negative, and neutral events.
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Emoções , Humanos , Feminino , Masculino , Criança , Pré-Escolar , Adulto , Compreensão , Julgamento , Percepção Social , Desenvolvimento Infantil/fisiologia , Tristeza/psicologia , Fatores EtáriosRESUMO
Blood gas analyses have previously been performed for giraffe under anesthesia and with physical restraint in a chute; however, reference values for giraffe that are trained to participate in venipuncture without chemical or physical restraint have not previously been described. Using a point-of-care blood gas and lactate analyzer and 20 giraffe trained for voluntary phlebotomy, values were determined for venous blood gasses and plasma lactate concentration. Ninety-five percent confidence in the mean values for venous pH (7.34-7.46), partial pressure of carbon dioxide (PCO2; 28.5-37.8 mmHg), partial pressure of oxygen (PO2; 56-102 mmHg), bicarbonate (HCO3 -; 18.9-21.0 mmol/L), base excess (BE; -6.0 to -3.6 mmol/L), total carbon dioxide (TCO2; 19.9-22.0 mmol/L), and lactate (0.32-0.56 mmol/L) were calculated. This is the first report on venous blood gas analysis values for giraffe without chemical or physical restraint. These data will provide a reference for clinical interpretation of venous blood gas and lactate values in giraffe and demonstrate some of the potential diagnostic benefits to training giraffe and other zoo species for voluntary medical procedures.
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Gasometria , Ácido Láctico , Flebotomia , Animais , Gasometria/veterinária , Flebotomia/veterinária , Ácido Láctico/sangue , Veias Jugulares , Masculino , Feminino , Animais de Zoológico , Ruminantes/sangue , Valores de Referência , Dióxido de Carbono/sangueRESUMO
Identifying common causes of mortality in zoo giraffe (Giraffa spp.) and okapi (Okapia johnstoni) provides an opportunity to help improve welfare and population management for these endangered species. Mortality reports from 1,024 giraffe and 95 okapi in zoos were compiled from the Species 360 Zoological Information Management Software (ZIMS) utilizing the Morbidity & Mortality Analysis tool. Thirty years of mortality reports (1991-2020) were evaluated to help identify trends and evaluate the impacts, if any, of changes over time in husbandry and management practices. The most common causes of death for giraffe from 1991 to 2015 were neonatal issues (234/845, 27.7%), trauma (213/845, 25.2%), noninfectious disease (190/845, 22.5%), and infectious disease (188/845, 22.2%). In comparison, the most common causes of mortality for giraffe from 2016 to 2020, were noninfectious disease (78/179, 43.6%), trauma (39/179, 21.8%), neonatal issues (39/179, 21.8%), and infectious disease (17/179, 9.5%). The most common cause of death for okapi from 1991 to 2015 were neonatal issues (29/64, 45.3%), infectious disease (13/64, 20.3%), noninfectious disease (11/64, 17.2%), and trauma (10/64, 15.6%). In comparison, the most common cause of death for okapi from 2016 to 2020 was noninfectious disease (15/31, 48.4%), neonatal issues (8/31, 25.8%), and infectious disease (5/31, 16.1%). The results suggest that zoo giraffids have had a relative decrease in mortality from infectious diseases in recent years, whereas death from noninfectious causes has increased significantly. Trauma-related giraffe mortalities and neonatal mortality in both giraffe and okapi, although decreasing in prevalence between time periods, continue to be important causes of death in zoos. This is the first descriptive mortality review for the Giraffidae family and provides data on potential giraffe and okapi health issues that zoos could proactively address.
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Doenças Transmissíveis , Girafas , Doenças não Transmissíveis , Animais , Doenças Transmissíveis/veterinária , Programas de Assistência Gerenciada , Doenças não Transmissíveis/veterinária , Estudos Retrospectivos , RuminantesRESUMO
Growing resistance to current antiparasitic medications, both in livestock and in zoological species under human care, makes it imperative to evaluate available drugs on the market, such as eprinomectin. In this prospective study, five males and one female of reticulated (Giraffa reticulata; n = 2), Masai (Giraffa tippelskirchii; n = 1), Nubian (Giraffa camelopardalis; n = 2), and hybrid subspecies (n = 1) of giraffe, received 1.5 mg/kg eprinomectin topically along the dorsum. Using high-performance liquid chromatography, concentrations of eprinomectin in plasma samples collected at 0, 4, 24, and 48 h, and 7, 14, 21, and 28 d were evaluated following drug administration. Complete blood cell counts and biochemistry panels were performed before (n = 6) and after (n = 3) eprinomectin administration. Samples for modified double centrifugal fecal flotation (n = 6) were evaluated prior to eprinomectin administration to evaluate for endoparasites and were repeated after the study (n = 5). Noncompartmental pharmacokinetic analysis was applied to the data. The observed maximum plasma concentration was 11.45 ng/ml and the time of observed maximum concentration was 2.67 d. The mean terminal half-life was 5.16 d. No adverse effects were observed related to eprinomectin administration and no blood work changes were observed. Parasite loads decreased (n = 3) or did not change (n = 2) after eprinomectin administration. The mean peak plasma concentration of eprinomectin in giraffe was similar to that achieved in cattle, despite using three times the dose.
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Anti-Helmínticos , Girafas , Ivermectina/análogos & derivados , Masculino , Humanos , Feminino , Animais , Bovinos , Anti-Helmínticos/uso terapêutico , Estudos Prospectivos , Administração Tópica , Ivermectina/uso terapêuticoRESUMO
Plasmodesmata are cytosolic bridges, lined by the plasma membrane and traversed by endoplasmic reticulum; plasmodesmata connect cells and tissues, and are critical for many aspects of plant biology. While plasmodesmata are notoriously difficult to extract, tissue fractionation and proteomic analyses can yield valuable knowledge of their composition. Here we have generated two novel proteomes to expand tissue and taxonomic representation of plasmodesmata: one from mature Arabidopsis leaves and one from the moss Physcomitrium patens, and leveraged these and existing data to perform a comparative analysis to identify evolutionarily conserved protein families that are associated with plasmodesmata. Thus, we identified ß-1,3-glucanases, C2 lipid-binding proteins, and tetraspanins as core plasmodesmal components that probably serve as essential structural or functional components. Our approach has not only identified elements of a conserved plasmodesmal proteome, but also demonstrated the added power offered by comparative analysis for recalcitrant samples. Conserved plasmodesmal proteins establish a basis upon which ancient plasmodesmal function can be further investigated to determine the essential roles these structures play in multicellular organism physiology in the green lineages.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Plasmodesmos/metabolismo , Proteômica , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Proteoma/metabolismoRESUMO
The plasma membrane (PM) is composed of heterogeneous subdomains, characterized by differences in protein and lipid composition. PM receptors can be dynamically sorted into membrane domains to underpin signaling in response to extracellular stimuli. In plants, the plasmodesmal PM is a discrete microdomain that hosts specific receptors and responses. We exploited the independence of this PM domain to investigate how membrane domains can independently integrate a signal that triggers responses across the cell. Focusing on chitin signaling, we found that responses in the plasmodesmal PM require the LysM receptor kinases LYK4 and LYK5 in addition to LYM2. Chitin induces dynamic changes in the localization, association, or mobility of these receptors, but only LYM2 and LYK4 are detected in the plasmodesmal PM. We further uncovered that chitin-induced production of reactive oxygen species and callose depends on specific signaling events that lead to plasmodesmata closure. Our results demonstrate that distinct membrane domains can integrate a common signal with specific machinery that initiates discrete signaling cascades to produce a localized response.
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Arabidopsis/fisiologia , Quitina/metabolismo , Nicotiana/fisiologia , Plasmodesmos/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fenômenos Biomecânicos , Membrana Celular/fisiologia , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Mecanotransdução Celular/fisiologia , Folhas de Planta/fisiologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Espécies Reativas de OxigênioRESUMO
BACKGROUND: Clostridioides difficile infection (CDI) is a form of antibiotic-associated infectious diarrhoea resulting in significant morbidity and mortality. Community-acquired disease in low-risk individuals is increasingly recognised. There are limited New Zealand data published. AIM: To determine the incidence and location of onset of CDI cases in the Manawatu region, and further describe the demographics, risk factors and prevalent C. difficile ribotypes of the population. METHODS: We performed an incidence case-control study of CDI in the Manawatu region between September 2018 and September 2019. Cases were matched to controls with a negative test for C. difficile. Demographic and comorbidity data, location of onset, drug exposure, disease recurrence and 30-day mortality were collected. Ribotype analysis was performed on C. difficile isolates. RESULTS: Thirty-two specimens tested toxin positive over 12 months, yielding an incidence of 18.3 cases per 100 000 person-years. Twenty-five percent of cases had community onset disease. Cases were more likely to have had amoxicillin/clavulanate or ceftriaxone prescribed. Elevated blood white cell count and lower HbA1c were significantly associated with CDI. The dominant ribotype was 014/020. Two cases were RT 023. CONCLUSION: Our data are similar to previous national data. RT 023 has not been previously reported in New Zealand and has been associated with severe colitis. We demonstrated a significant proportion of community-acquired cases and the true incidence might be higher. Vigilance for community onset disease is required. These data may allow observation of temporal changes in incidence and infection patterns of CDI in New Zealand.
Assuntos
Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Estudos de Casos e Controles , Infecções por Clostridium/epidemiologia , Infecção Hospitalar/epidemiologia , Diarreia , Humanos , Incidência , Nova Zelândia/epidemiologia , Ribotipagem , Centros de Cuidados de Saúde SecundáriosRESUMO
Developmentalists have investigated relief as a counterfactually mediated emotion, but not relief experienced when negative events end-so-called temporal relief. This study represents the first body of work to investigate the development of children's understanding of temporal relief and compare it with their understanding of counterfactual relief. Across four experiments (407 children aged 4-11 years and 60 adults; 52% female), we examined children's ability to attribute counterfactual and temporal relief to others. In Experiment 1, 7- to 10-year-olds typically judged that two characters would feel equally happy despite avoiding or enduring an event that was unpleasant for one character. Using forced-choice procedures, Experiments 2 to 4 showed that a fledgling ability to attribute relief to others emerges at 5 to 6 years of age and that the tendency to make these attributions increases with age. The experiments in this study provide the first positive evidence in the literature as to when children can begin to attribute both counterfactual and temporal instances of relief to others. Overall, there was little evidence for separate developmental trajectories for understanding counterfactual and temporal relief, although in Experiment 4 there was an indication that, under scaffolded contexts, some children find it easier to attribute counterfactual relief rather than temporal relief to others.
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Emoções , Percepção Social , Adulto , Criança , Desenvolvimento Infantil , Pré-Escolar , Feminino , Felicidade , Humanos , MasculinoRESUMO
Wake-up receivers (WuRX) present an opportunity to reduce average power consumption of IoT transceivers, however achieving sensitivity and interferer tolerance while providing wideband matching and sharing an antenna interface present a significant challenge for existing architectures. This paper presents a primary/WuRX which utilizes a quadrature hybrid coupler based N-Path mixer first architecture to simultaneously achieve low noise, wideband matching and a shared antenna interface. The passive-mixer first approach and a two-code modulated multi-tone signaling scheme provide interferer tolerance in the WuRX. The paper analyzes gain/power trade-offs in the proposed architecture in the context of noise impact with multi-tone WuRX signaling. The proposed architecture is implemented in 65 nm CMOS and occupies 2.25 mm 2. The primary RX achieves 3.8 dB NF and 0.75 dBm out-of-band P1dB with 440µW power consumption. The WuRX achieves -86 dBm sensitivity for 10kb/s data rate and up to -40 dB signal-to-interferer ratio (SIR) with 171µW power consumption.
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Giraffe skin disease (GSD) is an emerging disease of free-ranging giraffe recognized in the last 25 years in several species, including the critically endangered Nubian giraffe (Giraffa camelopardalis camelopardalis) of Uganda. Identifying the cause of GSD and understanding its impact on health were deemed paramount to supporting these vulnerable populations. Sixty-four giraffes were immobilized in Murchison Falls National Park, Uganda, from 2017 to 2019, and GSD lesions were opportunistically biopsied. Fifty-five giraffes (86%) had GSD lesions on the neck, axilla, chest, and cranial trunk. Lesions were categorized into early, intermediary, and dormant stages based on gross and histological characteristics. Early lesions were smaller, crusted nodules with eosinophilic and pyogranulomatous dermatitis and furunculosis. Intermediary lesions were thick plaques of proliferative and fissured hyperkeratosis and acanthosis with dense dermal granulation tissue and severe eosinophilic and granulomatous dermatitis. Lesions appeared to resolve to dormancy, with dormant lesions consisting of hairless plaques of hyperkeratosis with dermal scarring and residual inflammation. The periphery of early and intermediary lesions included follicular granulomas containing adult filarid nematodes, with myriad encysted microfilariae in the superficial dermis. Stage L3 larvae were common in early and intermediary lesions, and dormant lesions had remnant encysted microfilariae with no adult or stage L3 larvae. Nematodes were morphologically and genetically novel with close identity to Stephanofilaria spp. and Brugia malayi, which cause infectious filariasis. Identification of potential insect vectors, long-term monitoring of GSD lesions, and evaluating response to therapy is ongoing in the efforts to help conserve the Nubian giraffe.
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Dermatite , Filariose , Girafas , Dermatopatias , Animais , Dermatite/patologia , Dermatite/veterinária , Filariose/patologia , Filariose/veterinária , Pele/patologia , Dermatopatias/patologia , Dermatopatias/veterináriaRESUMO
Research indicates that, relative to the general public and most other types of public safety personnel, correctional workers are more likely to engage in suicide ideation, planning, and attempts. Yet, less is known about lived experiences towards, of, and beyond suicidality among correctional staff. To contribute to this gap in knowledge, the current study draws on qualitative, open-ended survey response data (n = 94) to explore how Canadian provincial correctional workers navigate experiences of suicide, with a focus on the individual, personal, and social factors tied to experiences towards and of suicide thoughts and behaviours. By engaging the seminal works of Foucault, Zizek, and Deleuze and Guattari, we explore respondents' distinct forms of agency when grappling with, challenging, and transcending thoughts around suicide. We then discuss the research implications, with an emphasis on providing correctional workers with confidential, non-stigmatised well-being and treatment-seeking resources and processes, and more health care funding to fully cover timely and sufficient mental health treatment, prevention, and intervention.
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Ideação Suicida , Humanos , Canadá , Inquéritos e QuestionáriosRESUMO
Alfaxalone, a neuroactive steroid with anesthetic properties, is considered safe when used alone or in combination with other drugs for anesthesia at recommended species doses, and its use has been studied in numerous species. The objective of this study was to assess the pharmacokinetics and pharmacodynamics of IM alfaxalone in Indian peafowl (Pavo cristatus; hereafter peafowl). Eight female peafowl from one zoological institution were used. A control blood sample was obtained before administration of either 10 mg/kg (n = 4) or 20 mg/kg (n = 4) alfaxalone. Blood was collected at 5, 10, 15, 30, and 60 min after alfaxalone injection, with monitoring of sedation score, heart rate, and respiratory rate at each time point. Four peahens receiving a 10 mg/ kg dose had subjectively smoother inductions and recoveries, although sedation level was generally scored as low, with no adverse reactions noted. They were considered fully recovered by the 60-min postinjection time point, although measurable alfaxalone plasma concentrations remained present. Four peahens receiving 20 mg/kg IM experienced adverse effects including seizure-like episodes and hypersensitivity to stimuli throughout the study. This dosing group experienced prolonged recoveries consistent with high plasma concentrations (>3,000 ng/ml). Based on these results, use of 20 mg/kg IM alfaxalone as the sole anesthetic agent is not recommended in this species. Further studies should determine whether alfaxalone in conjunction with other anesthetic or analgesic agents could provide better sedation and smoother induction and recovery for peafowl and to assess the pharmacokinetics and pharmacodynamics of alfaxalone in other avian species.
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Anestesia , Anestésicos , Pregnanodionas , Anestesia/veterinária , Anestésicos/farmacologia , Animais , Feminino , Injeções Intramusculares/veterinária , Pregnanodionas/farmacologiaRESUMO
A single-inductor self-starting boost converter is presented suitable for thermoelectric energy harvesting from human body heat. In order to extract maximum energy from a thermoelectric generator (TEG) at small temperature gradients, a loss-aware maximum power point tracking (MPPT) scheme was developed that enables the harvester to achieve high end-to-end efficiency at low input voltages. The boost converter is implemented in a 0.18 µm CMOS technology and is more than 75% efficient for a matched input voltage range of 15 mV-100 mV, with a peak efficiency of 82%. Enhanced power extraction enables the converter to sustain operation at an input voltage as low as 3.5 mV. In addition, the boost converter self-starts with a minimum TEG voltage of 50 mV leveraging a dual-path architecture without using additional off-chip components.
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In zoos, rock hyrax (Procavia capensis) are commonly maintained in groups and population control is necessary. Here we report on hydrometra prevalence in a group of rock hyraxes. Prevalence of hydrometra in this small group (4/8) far exceeds reproductive pathology prevalence previously reported for this species under managed care. Affected females were nulliparous, but had not been contracepted; instead they were maintained as a single-sex group. The first case presented as sudden death and three additional cases were diagnosed antemortem via ultrasound. Two of these underwent ovariohysterectomy to treat the severe hydrometra. The last case was a mild hydrometra and during follow-up exam was found to have spontaneously resolved. Detailed information regarding clinical presentation, diagnostics and surgical techniques are provided.
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Procaviídeos , Doenças Uterinas/veterinária , Animais , Feminino , Masculino , Doenças Uterinas/diagnóstico , Doenças Uterinas/patologia , Doenças Uterinas/cirurgiaRESUMO
Extinction threatens many species yet is predicted by few factors across the plant tree of life (ToL). Taxon age is one factor that may associate with extinction if occupancy of geographic and adaptive zones varies with time, but evidence for such an association has been equivocal. Age-dependent occupancy can also influence diversification rates and thus extinction risk where new taxa have small range and population sizes. To test how age, diversification, and range size were correlated with extinction, we analyzed 639 well-sampled genera representing 8,937 species from across the plant ToL. We found a greater proportion of species were threatened by contemporary extinction in younger and faster-diversifying genera. When we directly tested how range size mediated this pattern in two large, well-sampled groups, our results varied. In conifers, potential range size was smaller in older species and was correlated with higher extinction risk. Age on its own had no direct effect on extinction when accounting for its influence on range size. In palm species, age was neither directly nor indirectly correlated with extinction risk. Our results suggest that range size dynamics may explain differing patterns of extinction risk across the ToL, with consequences for biodiversity conservation.
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Evolução Biológica , Conservação dos Recursos Naturais , Extinção Biológica , Especiação Genética , Dispersão Vegetal , Mudança Climática , Modelos Biológicos , Densidade Demográfica , Especificidade da EspécieRESUMO
This paper presents a batteryless heartbeat detection system-on-chip (SoC) powered by human body heat. An adaptive threshold generation architecture using pulse-width locked loop (PWLL) is developed to detect heartbeats from electrocardiogram (ECG) in the presence of motion artifacts. The sensing system is autonomously powered by harvesting thermal energy from human body heat using a thermoelectric generator (TEG) coupled to a low-voltage, self-starting boost converter and integrated power management system. The SoC was implemented in a 0.18 µm CMOS process and is fully functional with a minimum input power of 20 µW, provided by a portable TEG at 20 mV with a ~0.5 °C temperature gradient. The complete system demonstrates motion-adaptive, power-autonomous heartbeat detection for sustainable healthcare using wearable devices.
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OBJECTIVE: To present the results of clinical, surgical, and histopathologic procedures and how these were compared with the initial presumptive clinical diagnosis in a corn snake (Pantherophis guttatus) presenting with subspectacular fluid opacity; and to improve upon currently established surgical enucleation techniques in the snake. ANIMAL STUDIED: An 8-month-old corn snake was presented for enlarged globe OD. PROCEDURES: The following diagnostics were performed: systemic and ophthalmic examinations, complete blood count, cytology and culture of subspectacular fluid, and histopathology of enucleated globe and spectacle. Enucleation was performed in a routine fashion with the addition of a porcine small intestinal submucosa bioscaffold graft (SISplus™; Avalon Medical, Stillwater, MN), sutured over the orbit. RESULTS: Systemic examination revealed signs of maxillary stomatitis. Ophthalmic examination revealed semitransparent fluid in the subspectacular space. Complete blood count was unremarkable. Cytology of fluid obtained via subspectacular centesis was acellular, and culture grew Clostridium perfringens, which was consistent with the clinical suspicion of right maxillary stomatitis. Histopathology of the enucleated globe revealed spectaculitis, characterized by regional heterophilic inflammation, and no evidence of lymph dissection in the (peri)ocular tissues. The final diagnosis was a subspectacular abscess. Follow-up revealed that the SIS graft provided excellent healing and cosmesis of the surgical site. CONCLUSIONS: While there are reports of lymphatic fluid dissection between skin layers during ecdysis, which can result in an opaque spectacle, the fluid opacity in this case was attributed to a subspectacular abscess secondary to an ascending oral infection. Addition of biological wound dressing may contribute to positive post-enucleation outcome in the snake.