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BACKGROUND AND AIMS: Palm fossils are often used as evidence for warm and wet palaeoenvironments, reflecting the affinities of most modern palms. However, several extant palm lineages tolerate cool and/or arid climates, making a clear understanding of the taxonomic composition of ancient palm communities important for reliable palaeoenvironmental inference. However, taxonomically identifiable palm fossils are rare and often confined to specific facies. Although the resolution of taxonomic information they provide remains unclear, phytoliths (microscopic silica bodies) provide a possible solution because of their high preservation potential under conditions where other plant fossils are scarce. We thus evaluate the taxonomic and palaeoenvironmental utility of palm phytoliths. METHODS: We quantified phytolith morphology of 97 modern palm and other monocot species. Using this dataset, we tested the ability of five common discriminant methods to identify nine major palm clades. We then compiled a dataset of species' climate preferences and tested if they were correlated with phytolith morphology using a phylogenetic comparative approach. Finally, we reconstructed palm communities and palaeoenvironmental conditions at six fossil sites. KEY RESULTS: Best-performing models correctly identified phytoliths to their clade of origin only 59 % of the time. Although palms were generally distinguished from non-palms, few palm clades were highly distinct, and phytolith morphology was weakly correlated with species' environmental preferences. Reconstructions at all fossil sites suggested that palm communities were dominated by Trachycarpeae and Areceae, with warm, equable climates and high, potentially seasonal rainfall. However, fossil site reconstructions had high uncertainty and often conflicted with other climate proxies. CONCLUSIONS: While phytolith morphology provides some distinction among palm clades, caution is warranted. Unlike prior spatially restricted studies, our geographically and phylogenetically broad study indicates phytolith morphology may not reliably differentiate most palm taxa in deep time. Nevertheless, it reveals distinct clades, including some likely to be palaeoenvironmentally informative.
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Arecaceae , Evolución Biológica , Fósiles , Filogenia , Arecaceae/anatomía & histología , Arecaceae/fisiología , Fósiles/anatomía & histología , ClimaRESUMEN
Figures: Cory cat panel figureDrawing of bite force measuring equipment and indentation rig Pygocentrus nattereri jaw muscle morphology and skull anatomyBox plot grid of number of Pygocentrus nattereri bites before puncture along different body regions of Corydoras trilineatus during feeding trials resultsDrawing of color-coded Corydoras trilineatus with attack frequencies and average bites until puncture by Pygocentrus nattereriBox plot of average voluntary juvenile Pygocentrus nattereri bite forces to standard lengthPanel of linear ordinary least-squares regressions of Pygocentrus nattereri bite force to adductor mandibulae mass, standard length, and body massOrdinary least-squares regressions of voluntary bites to restrained bites of Pygocentrus nattereriPanel of indentation tests for intact and removed Corydoras trilineatus scutesPanel of indentation tests for Corydoras trilineatus body region. Synopsis: There is an evolutionary arms race between predators and prey. In aquatic environments, predatory fishes often use sharp teeth, powerful bites, and/or streamlined bodies to help capture their prey quickly and efficiently. Conversely, prey are often equipped with antipredator adaptations including: scaly armor, sharp spines, and/or toxic secretions. This study focused on the predator-prey interactions between the armored threestripe cory catfish (Corydoras trilineatus) and juvenile red-bellied piranha (Pygocentrus nattereri). Specifically, we investigated how resistant cory catfish armor is to a range of natural and theoretical piranha bite forces and how often this protection translated to survival from predator attacks by Corydoras. We measured the bite force and jaw functional morphology of P. nattereri, the puncture resistance of defensive scutes in C. trilineatus, and the in situ predatory interactions between the two. The adductor mandibulae muscle in juvenile P. nattereri is robust and delivers an average bite force of 1.03 N and maximum bite force of 9.71 N, yet its prey, C. trilineatus, survived 37% of confirmed bites without any damage. The C. trilineatus armor withstood an average of nine bites before puncture by P. nattereri. Predation was successful only when piranhas bit unarmored areas of the body, at the opercular opening and at the caudal peduncle. This study used an integrative approach to understand the outcomes of predator-prey interactions by evaluating the link between morphology and feeding behavior. We found that juvenile P. nattereri rarely used a maximal bite force and displayed a net predation success rate on par with other adult vertebrates. Conversely, C. trilineatus successfully avoided predation by orienting predator attacks toward their resilient, axial armor and behavioral strategies that reduced the predator's ability to bite in less armored regions of the body.
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BACKGROUND AND OBJECTIVES: While adult chronic cough has high burden, its phenotypes, particularly those without aetiologically related underlying conditions, are understudied. We investigated the prevalence, lung function and comorbidities of adult chronic cough phenotypes. METHODS: Data from 3608 participants aged 53 years from the Tasmanian Longitudinal Health Study (TAHS) were included. Chronic cough was defined as cough on most days for >3 months in a year. Chronic cough was classified into "explained cough" if there were any one of four major cough-associated conditions (asthma, COPD, gastroesophageal reflux disease or rhinosinusitis) or "unexplained cough" if none were present. Adjusted regression analyses investigated associations between these chronic cough phenotypes, lung function and non-respiratory comorbidities at 53 years. RESULTS: The prevalence of chronic cough was 10% (95%CI 9.1,11.0%) with 46.4% being "unexplained". Participants with unexplained chronic cough had lower FEV1/FVC (coefficient: -1.2% [95%CI:-2,3, -0.1]) and increased odds of comorbidities including obesity (OR=1.6 [95%CI: 1.2, 2.3]), depression (OR=1.4 [95%CI: 1.0, 2.1]), hypertension (OR=1.7 [95%CI: 1.2, 2.4]) and angina, heart attack or myocardial infarction to a lesser extent, compared to those without chronic cough. Participants with explained chronic cough also had lower lung function than both those with unexplained chronic cough and those without chronic cough. CONCLUSIONS: Chronic cough is prevalent in middle-age and a high proportion is unexplained. Unexplained cough contributes to poor lung function and increased comorbidities. Given unexplained chronic cough is not a symptom of major underlying respiratory conditions it should be targeted for better understanding in both clinical settings and research.
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Aboveground ecological impacts associated with agricultural land use change are evident as natural plant communities are replaced with managed production systems. These impacts have been extensively studied, unlike those belowground, which remain poorly understood. Soil bacteria are good candidates to monitor belowground ecological dynamics due to their prevalence within the soil system and ability to survive under harsh and changing conditions. Here, we use soil physicochemical assessment and 16S rRNA gene sequencing to investigate the soil physical and bacterial assemblage changes across a mixed-use agricultural landscape. We assess soil from remnant vegetation (Eucalyptus mallee), new and old vineyards, old pasture, and recently revegetated areas. Elevated concentrations of nitrogen (NO3-) and plant-available (Colwell) phosphorus were identified in the managed vineyard systems, highlighting the impact of agricultural inputs on soil nutrition. Alpha diversity comparison revealed a significant difference between the remnant mallee vegetation and the vineyard systems, with vineyards supporting highest bacterial diversity. Bacterial community composition of recently revegetated areas was similar to remnant vegetation systems, suggesting that bacterial communities can respond quickly to aboveground changes, and that actions taken to restore native plant communities may also act to recover natural microbial communities, with implications for soil and plant health. Findings here suggest that agriculture may disrupt the correlation between above- and belowground diversities by altering the natural processes that otherwise govern this relationship (e.g. disturbance, plant production, diversity of inputs), leading to the promotion of belowground microbial diversity in agricultural systems.
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Agricultura , Suelo , Suelo/química , ARN Ribosómico 16S/genética , Bacterias/genética , Plantas , Microbiología del SueloRESUMEN
Navajo children disproportionately experience poor asthma outcomes. Following a one-year community engagement period with key stakeholders from the Navajo Nation, the Community Asthma Program (CAP) was created using evidenced based programs with the goal of reducing asthma disparities among Navajo children. CAP is being evaluated with a six-year, multi-site step-wedge design in three Navajo communities: Tuba City, Chinle and Fort Defiance, Arizona. The primary outcome is asthma exacerbations defined as use of systemic oral corticosteroids, asthma hospitalizations, asthma related ED visits, and ICU admissions. Asthma exacerbations will be measured using data from the electronic medical records of the three community health care centers. Secondary outcomes include will changes in asthma-related events and asthma control. The RE-AIM ( R each and representativeness, 2) E ffectiveness, 3) A doption, 4) I mplementation, and 5) M aintenance) framework is being used to guide the implementation evaluation which includes iterative collection and analysis of process data to identify facilitators and barriers, describe relevant organizational contexts, and inform strategies for dissemination. The CAP intervention requires community engagement and participation, building community capacity, incorporating evidenced-based guidelines and practices while ensuring program strategies actively involve Navajo community members during all steps of the intervention. The outcome of this trial will allow us to determine the effectiveness of a multi-component, community-focused intervention to improve asthma in a tribal community.
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BACKGROUND: Older companion dogs naturally develop a dementia-like syndrome with biological, clinical and therapeutic similarities to Alzheimer disease (AD). Given there has been no new safe, clinically effective and widely accessible treatment for AD for almost 20 years, an all-new cell therapeutic approach was trialled in canine veterinary patients, and further modelled in aged rats for more detailed neurobiological analysis. METHODS: A Phase 1/2A veterinary trial was conducted in N = 6 older companion dogs with definitive diagnosis of Canine Cognitive Dysfunction (CCD). Treatment comprised direct microinjection of 250,000 autologous skin-derived neuroprecursors (SKNs) into the bilateral hippocampus using MRI-guided stereotaxis. Safety was assessed clinically and efficacy using the validated Canine Cognitive Dysfunction Rating Scale (CCDR) at baseline and 3-month post treatment. Intention to treat analysis imputed a single patient that had a surgical adverse event requiring euthanasia. Three dog brains were donated following natural death and histology carried out to quantify Alzheimer pathology as well as immature neurons and synapses; these were compared to a brain bank (N = 12) of untreated aged dogs with and without CCD. Further, an age-related memory dysfunction rat model (N = 16) was used to more closely evaluate intrahippocampal engraftment of canine SKN cells, focusing on mnemonic and synaptic effects as well as donor cell survival, neurodifferentation and electrophysiologic circuit integration in a live hippocampal slice preparation. RESULTS: Four out-of-five dogs improved on the primary clinical CCDR endpoint, three fell below diagnostic threshold, and remarkably, two underwent full syndromal reversal lasting up to 2 years. At post mortem, synaptic density in the hippocampus specifically was nine standard deviations above non-treated dogs, and intensity of new neurons also several fold higher. There was no impact on AD pathology or long-term safety signals. Modelling in aged rats replicated the main canine trial findings: hippocampally-dependent place memory deficits were reversed and synaptic depletion rescued. In addition, this model confirmed donor cell survival and migration throughout the hippocampus, neuronal differentiation in situ, and physiologically-correct integration into pyramidal layer circuits. CONCLUSIONS: With further development, SKN cell therapy may have potential for treating carefully chosen AD patients based on neurosynaptic restoration in the hippocampus.
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Enfermedad de Alzheimer , Tratamiento Basado en Trasplante de Células y Tejidos , Enfermedades de los Perros , Animales , Perros , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/veterinaria , Enfermedades de los Perros/terapia , Hipocampo/patología , Células-Madre Neurales/trasplanteRESUMEN
BACKGROUND: The landscape of dermatology services, already rapidly evolving into an increasingly digital one, has been irretrievably altered by the COVID-19 (SARS-CoV-2) pandemic. Data are needed to assess how best to deliver virtual dermatology services in specific patient subgroups in an era of ongoing social distancing and beyond. Initial studies of teledermatology in paediatric populations suggest that many of the problems experienced in adult telemedicine are more apparent when treating children and come with additional challenges. AIM: To evaluate the efficacy of a virtual paediatric dermatology telephone clinic in comparison to traditional face-to-face (FTF) clinics, both from the clinician and patient/parental perspective. METHODS: We carried out a prospective service evaluation examining a single centre cohort of paediatric dermatology patients managed during the COVID-19 pandemic via a telephone clinic supported by images. The study period covered June-September 2020. Data on outcomes were collected from clinicians and a qualitative patient/parental telephone survey was undertaken separately. A five-point Likert scale was used to assess both satisfaction and levels of agreement regarding whether a telephone clinic was more convenient than an FTF clinic. RESULTS: Of 116 patients included, 24% were new and 76% were follow-up patients, with a mixture of inflammatory dermatoses (75%) and lesions (25%). From the clinician's perspective, most consultations (91%) were successfully completed over the telephone. However, qualitative patient and parent feedback paradoxically illustrated that although nearly all (98%) respondents had no outstanding concerns, 52% felt highly unsatisfied and only 22% agreed that telephone clinics were more convenient. Most (65%) preferred FTF follow-up in the future. Statistical analysis using χ² test showed that among those with established follow-ups, the preference for future consultation type was independent of specific reasons for follow-up. CONCLUSIONS: Our study demonstrates a clear discrepancy between the practical successes of a virtual service from the clinician's perspective compared with the patient/parental perspective. Parental anxiety appears to be less effectively allayed virtually than with FTF. This raises the question of whether there is a role for virtual paediatric telephone clinics in the postpandemic future, which may be better left to patients/parents to decide on an individual basis.
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Actitud del Personal de Salud , Dermatología , Prioridad del Paciente , Satisfacción del Paciente , Consulta Remota , Adolescente , Instituciones de Atención Ambulatoria , COVID-19 , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pandemias , Estudios Prospectivos , Encuestas y CuestionariosRESUMEN
Blood pressure (BP) is one of the most crucial vital signs of the human body that can be assessed as a critical risk factor for severe health conditions such as cardiovascular diseases (CVD) and hypertension. An accurate, continuous, and cuff-less BP monitoring technique could help clinicians improve the prevention, detection, and diagnosis of hypertension and manage related treatment plans. Notably, the complex and dynamic nature of the cardiovascular system necessitates that any BP monitoring system could benefit from an intelligent technology that can extract and analyze compelling BP features. In this study, a support vector regression (SVR) model was developed to estimate systolic blood pressure (SBP) and diastolic blood pressure (DBP) continuously. We selected a set of features commonly used in previous studies to train the proposed SVR model. A total of 120 patients with available ECG, PPG, DBP and SBP data were chosen from the Medical Information Mart for Intensive Care (MIMIC III) dataset to validate the proposed model. The results showed that the average root mean square error (RMSE) of 2.37 mmHg and 4.18 mmHg were achieved for SBP and DBP, respectively.
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Hipertensión , Fotopletismografía , Presión Arterial , Presión Sanguínea , Determinación de la Presión Sanguínea , Humanos , Hipertensión/diagnósticoAsunto(s)
COVID-19 , Dermatología , Telemedicina , Electrónica , Humanos , Pacientes Internos , Pandemias , Derivación y Consulta , SARS-CoV-2RESUMEN
AIM: To audit scanning technique and patient doses for computed tomography (CT) colonography (CTC) examinations in a large UK region and to identify opportunities for quality improvement. MATERIALS AND METHODS: Scanning technique and patient dose data were gathered for both contrast-enhanced and unenhanced CTC examinations from 33 imaging protocols across 27 scanners. Measurements of patient weight and effective diameter were also obtained. Imaging protocols were compared to identify technique differences between similar scanners. Scanner average doses were calculated and combined to generate regional diagnostic reference limits (DRLs) for both examinations. RESULTS: The regional DRLs for contrast-enhanced examinations were volume CT dose index (CTDIvol) of 11 and 5 mGy for the two scan phases (contrast-enhanced and either delayed phase or non-contrast enhanced respectively), and dose-length product (DLP) of 740 mGy·cm. For unenhanced examinations, these were 5 mGy and 450 mGy·cm. These are notably lower than the national DRLs of 11 mGy and 950 mGy·cm. Substantial differences in scan technique and doses on similar scanners were identified as areas for quality-improvement action. CONCLUSION: A regional CTC dose audit has demonstrated compliance with national DRLs but marked variation in practice between sites for the dose delivered to patients, notably when scanners of the same type were compared for the same indication. This study demonstrates that the national DRL is too high for current scanner technology and should be revised.
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Colonografía Tomográfica Computarizada/métodos , Colonografía Tomográfica Computarizada/normas , Mejoramiento de la Calidad/estadística & datos numéricos , Dosis de Radiación , Colon/diagnóstico por imagen , Niveles de Referencia para Diagnóstico , Humanos , Estudios Prospectivos , Radiología , Reino UnidoAsunto(s)
COVID-19 , Dermatología/métodos , Fotograbar , Derivación y Consulta , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/terapia , Telemedicina/métodos , Triaje/métodos , Acné Vulgar/diagnóstico , Acné Vulgar/terapia , Alopecia/diagnóstico , Alopecia/terapia , Atención a la Salud , Dermatología/organización & administración , Eccema/diagnóstico , Eccema/terapia , Humanos , Intertrigo/diagnóstico , Intertrigo/terapia , Atención Primaria de Salud , Psoriasis/diagnóstico , Psoriasis/terapia , SARS-CoV-2 , Enfermedades Cutáneas Infecciosas/diagnóstico , Enfermedades Cutáneas Infecciosas/terapia , Telemedicina/organización & administración , Teléfono , Reino Unido , Urticaria/diagnóstico , Urticaria/terapiaRESUMEN
Natural and anthropogenic environmental changes in estuaries affect the growth and health of organisms living there, often along spatiotemporal gradients. Throughout the world's estuaries, aquaculture and wild oyster populations support food and cultural systems, so quantifying factors affecting growth may inspire interventions to prevent future losses of oyster productivity. In Willapa Bay (Washington, USA), an estuary that produces 10-20% of US oysters, oysters are primarily harvested for market from the lower estuary, putatively due to food limitation up-estuary. We present studies in which in situ experimental systems were designed to manipulate food availability in the upper, and in one case contrasting to the lower, estuary. Contrary to expectations, food addition did not improve survival, shell growth rate or tissue mass of post-metamorphosis juvenile Pacific oysters, Crassostrea gigas. Instead, the experiment did not recapitulate the impaired growth up-estuary that typifies on-bottom oyster outplants, and irrespective of food addition, growth rates in the upper estuary were equivalent to rapid summer growth (>10 mm month-1) in other regions of the bay. Multiple lines of evidence suggest that elevating oysters above the substrate in the experimental systems removed food limitation caused by reduced clearance rates, thus allowing oysters to grow rapidly, even when other environmental conditions such as carbonate chemistry were poor. This observation is consistent with experience of shellfish growers and a valuable observation for managers of wild and aquaculture shellfish in estuaries.
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[This corrects the article PMC8724865.].
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The de-agglomeration characteristics of single agglomerate-wall impaction are examined using high-resolution shadowgraph imaging. Experiments are performed to investigate the effects of constituent particle size (D 50 from 3-7 µ m) and air velocity on the individual size and velocity of de-agglomerated fragments at conditions relevant to dry powder inhalation systems. De-agglomerated fragment area and trajectories were used to differentiate between pseudo-elastic and inelastic collisions during de-agglomeration. Advanced image processing techniques have enabled provision of joint population distributions of fragment area and aspect ratio, which identify a bimodal dispersion of fragments during de-agglomeration. The bimodality is destroyed with increasing air velocity and also generally diminishes with time after impact. The experiment presented forms a platform for the detailed quantitative characterisation of de-agglomeration behaviour and can be useful towards the development and validation of related computational models for pharmaceutical dry powder inhalers.
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The entire landscape of dermatology service provision has been transformed by the current SARS-CoV-2 (COVID) pandemic, with virtual working having become the new norm across the UK. A pre-pandemic UK-wide survey of dermatology registrars in training demonstrated a huge shortfall in trainee confidence in their teledermatology skills, with only 15% feeling even slightly confident, while 96% of trainees surveyed felt that more teaching in this area was needed. We carried out a follow-up trainee survey during the COVID-19 pandemic, which showed that the sudden thrust into virtual working had achieved dramatic gains in trainee confidence, propelling the percentage of trainees that now felt slightly confident to 58%. However, the shortfall remains, as does the pressing need to incorporate teledermatology into the trainee teaching timetable.
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COVID-19/epidemiología , Dermatología/educación , Pandemias , Consulta Remota , Teletrabajo , Competencia Clínica , Estudios de Seguimiento , Humanos , SARS-CoV-2 , Encuestas y Cuestionarios , Reino Unido/epidemiologíaRESUMEN
AbstractFor many historical and contemporary experimental studies in marine biology, seawater carbonate chemistry remains a ghost factor, an uncontrolled, unmeasured, and often dynamic variable affecting experimental organisms or the treatments to which investigators subject them. We highlight how environmental variability, such as seasonal upwelling and biological respiration, drive variation in seawater carbonate chemistry that can influence laboratory experiments in unintended ways and introduce a signal consistent with ocean acidification. As the impacts of carbonate chemistry on biochemical pathways that underlie growth, development, reproduction, and behavior become better understood, the hidden effects of this previously overlooked variable need to be acknowledged. Here we bring this emerging challenge to the attention of the wider community of experimental biologists who rely on access to organisms and water from marine and estuarine laboratories and who may benefit from explicit considerations of a growing literature on the pervasive effects of aquatic carbonate chemistry changes.
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Laboratorios , Agua de Mar , Dióxido de Carbono , Carbonatos/análisis , Concentración de Iones de Hidrógeno , Océanos y MaresRESUMEN
Teledermatology has had an explosive impact on the provision of dermatology services in recent times, and even more so with the unprecedented situation created by the COVID-19 pandemic. Although teledermatology is not presently a feature of the Joint Royal Colleges of Physicians Training Board (JRCPTB) curriculum for dermatology training, this is due to change imminently. Specialty trainees need training in this area to be able to confidently and competently meet the demands of the changing face of dermatology services. We surveyed dermatology registrars in training across the UK, prior to the outbreak of COVID-19, to ascertain the teledermatology teaching available and trainee confidence in this area. Our survey found that only 15% of respondents felt slightly confident in their ability to deal with teledermatology referrals and almost all (96%) felt more teaching was needed.