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Chronic intermittent hypoxia (CIH, a model for sleep apnoea) is a major risk factor for several cardiovascular diseases. Autonomic imbalance (sympathetic overactivity and parasympathetic withdrawal) has emerged as a causal contributor of CIH-induced cardiovascular disease. Previously, we showed that CIH remodels the parasympathetic pathway. However, whether CIH induces remodelling of the cardiac sympathetic innervation remains unknown. Mice (male, C57BL/6J, 2-3 months) were exposed to either room air (RA, 21% O2 ) or CIH (alternating 21% and 5.7% O2 , every 6 min, 10 h day-1 ) for 8-10 weeks. Flat-mounts of their left and right atria were immunohistochemically labelled for tyrosine hydroxylase (TH, a sympathetic marker). Using a confocal microscope (or fluorescence microscope) and Neurlocudia 360 digitization and tracing system, we scanned both the left and right atria and quantitatively analysed the sympathetic axon density in both groups. The segmentation data was mapped onto a 3D mouse heart scaffold. Our findings indicated that CIH significantly remodelled the TH immunoreactive (-IR) innervation of the atria by increasing its density at the sinoatrial node, the auricles and the major veins attached to the atria (P < 0.05, n = 7). Additionally, CIH increased the branching points of TH-IR axons and decreased the distance between varicosities. Abnormal patterns of TH-IR axons around intrinsic cardiac ganglia were also found following CIH. We postulate that the increased sympathetic innervation may further amplify the effects of enhanced CIH-induced central sympathetic drive to the heart. Our work provides an anatomical foundation for the understanding of CIH-induced autonomic imbalance. KEY POINTS: Chronic intermittent hypoxia (CIH, a model for sleep apnoea) causes sympathetic overactivity, cardiovascular remodelling and hypertension. We determined the effect of CIH on sympathetic innervation of the mouse atria. In vivo CIH for 8-10 weeks resulted in an aberrant axonal pattern around the principal neurons within intrinsic cardiac ganglia and an increase in the density, branching point, tortuosity of catecholaminergic axons and atrial wall thickness. Utilizing mapping tool available from NIH (SPARC) Program, the topographical distribution of the catecholaminergic innervation of the atria were integrated into a novel 3D heart scaffold for precise anatomical distribution and holistic quantitative comparison between normal and CIH mice. This work provides a unique neuroanatomical understanding of the pathophysiology of CIH-induced autonomic remodelling.
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Hipertensión , Síndromes de la Apnea del Sueño , Ratones , Masculino , Animales , Ratones Endogámicos C57BL , Atrios Cardíacos/metabolismo , HipoxiaRESUMEN
BACKGROUND: Strict isolation of COVID-19 patients to prevent cross infection may inadvertently cause serious adverse outcomes including psychological harm, limitations to care, increased incidence of delirium, deconditioning and reduced quality of life. Previous research exploring the staff perspective of the effect of isolation on patients is limited. The aim of this study is to understand staff perceptions and interpretations of their experiences of the care and treatment of isolated patients and the impact of isolation on patients, families, and staff. METHOD: This qualitative, exploratory study is set in a major metropolitan, quaternary hospital in Melbourne, Australia. Data was collected in focus groups with clinical and non-clinical staff and analysed using content analysis. The hospital ethics committee granted approval. Each participant gave informed verbal consent. RESULTS: Participants included 58 nursing, medical, allied health, and non-clinical staff. Six main themes were identified: 1) Communication challenges during COVID-19; 2) Impact of isolation on family; 3) Challenges to patients' health and safety; 4) Impact on staff; 5) Challenging standards of care; 6) Contextual influences: policy, decision-makers and the environment. CONCLUSION: Isolating patients and restricting visitors resulted in good pandemic management, but staff perceived it came at considerable cost to staff and consumers. Innovative communication technology may facilitate improved connection between all parties. Mental health support is needed for patients, families, and staff. Further research using a co-design model with input from patients, families and staff is recommended to determine appropriate interventions to improve care. Preventing the spread of infection is essential for good pandemic management, but the cost to consumers and staff must be mitigated. Preparation for future pandemics must consider workforce preparedness, adapted models of care and workflow.
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COVID-19 , Infección Hospitalaria , Humanos , Pandemias , Calidad de Vida , Aislamiento de PacientesRESUMEN
This study assesses the ability of a new active fluorometer, the LabSTAF, to diagnostically assess the physiology of freshwater cyanobacteria in a reservoir exhibiting annual blooms. Specifically, we analyse the correlation of relative cyanobacteria abundance with photosynthetic parameters derived from fluorescence light curves (FLCs) obtained using several combinations of excitation wavebands, photosystem II (PSII) excitation spectra and the emission ratio of 730 over 685 nm (Fo(730/685)) using excitation protocols with varying degrees of sensitivity to cyanobacteria and algae. FLCs using blue excitation (B) and green−orange−red (GOR) excitation wavebands capture physiology parameters of algae and cyanobacteria, respectively. The green−orange (GO) protocol, expected to have the best diagnostic properties for cyanobacteria, did not guarantee PSII saturation. PSII excitation spectra showed distinct response from cyanobacteria and algae, depending on spectral optimisation of the light dose. Fo(730/685), obtained using a combination of GOR excitation wavebands, Fo(GOR, 730/685), showed a significant correlation with the relative abundance of cyanobacteria (linear regression, p-value < 0.01, adjusted R2 = 0.42). We recommend using, in parallel, Fo(GOR, 730/685), PSII excitation spectra (appropriately optimised for cyanobacteria versus algae), and physiological parameters derived from the FLCs obtained with GOR and B protocols to assess the physiology of cyanobacteria and to ultimately predict their growth. Higher intensity LEDs (G and O) should be considered to reach PSII saturation to further increase diagnostic sensitivity to the cyanobacteria component of the community.
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Cianobacterias , Ficobilisomas , Fluorescencia , Ficobilisomas/metabolismo , Fotosíntesis/fisiología , Cianobacterias/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , LuzRESUMEN
AIMS AND OBJECTIVES: The aim of this study was to determine how much time nurses spend on direct and indirect patient care in acute and subacute hospital settings. BACKGROUND: Quantifying direct and indirect nursing care provided during inpatient stay is vital to optimise the quality of care and manage resources. DESIGN: Time and motion cross-sectional observational study and reported the study according to the STROBE guideline. METHODS: Nurses working in an acute or subacute medical wards of a single health service participated. Nurses were observed twice for 2 h on the same day with an observer break in between sessions. Real-time task-related data were digitally recorded using the Work Observation Method By Activity Timing (WOMBAT) tool by a single research assistant. Frequency and time spent on pre-determined tasks were recorded and included direct care, indirect care, documentation, medication-related tasks, communication (professional) and other tasks. Task interruptions and multitasking were also recorded. RESULTS: Twenty-one nurses (acute n = 12, subacute n = 9) were observed during shifts between 7 AM and 9 PM in May-July 2021. A total of 7240 tasks were recorded. Nurses spent a third of their time on direct patient care (27% direct care and 3% medication administration). A total of 556 task interruptions occurred, mostly during documentation, and medication-related tasks. A further 1385 tasks were performed in parallel with other tasks, that is multitasking. CONCLUSIONS: Time spent on tasks was similar regardless of the setting and was consistent with previous research. We found differences in the distribution of tasks throughout the day between settings, which could have implications for workforce planning and needs to be investigated further. Interruptions occurred during documentation, direct care and medication-related tasks. Local-level strategies should be in place and regularly revised to reduce interruptions and prevent errors. Relevance to clinical practice The association between interruption and increased risk of error is well-established and should be an ongoing area of attention including observations and education provided in local settings.
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Atención de Enfermería , Humanos , Estudios de Tiempo y Movimiento , Flujo de Trabajo , Estudios Transversales , HospitalesRESUMEN
In this narrative review, we explore developments in the field of computational musculoskeletal model personalization using the Physiome and Musculoskeletal Atlas Projects. Model geometry personalization; statistical shape modeling; and its impact on segmentation, classification, and model creation are explored. Examples include the trapeziometacarpal and tibiofemoral joints, Achilles tendon, gastrocnemius muscle, and pediatric lower limb bones. Finally, a more general approach to model personalization is discussed based on the idea of multiscale personalization called scaffolds.
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Tendón Calcáneo , Modelación Específica para el Paciente , Humanos , Niño , Músculo Esquelético/fisiología , Articulación de la Rodilla , Modelos EstadísticosRESUMEN
Estimating the concentration of water constituents by optical remote sensing assumes absorption and scattering processes to be uniform over the observation depth. Using hyperspectral reflectance, we present a method to direct the retrieval of the backscattering coefficient (bb(λ)) from reflectance (> 600 nm) towards wavebands where absorption by water dominates the reflectance curve. Two experiments demonstrate the impact of hyperspectral inversion in the selected band set. First, optical simulations show that the resulting distribution of bb(λ) is sensitive to particle mixing conditions, although a robust indicator of non-uniformity was not found for all scenarios of stratification. Second, in the absence of spectral backscattering profiles from in situ data sets, it is shown how substituting the median of bb(λ) into a near infra-red / red band ratio algorithm improved chlorophyll-a estimates (root mean square error 75.45 mg m-3 became 44.13 mg m-3). This approach also allows propagation of the uncertainty in bb estimates to water constituent concentrations.
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OBJECTIVES: To determine the prevalence of body image dysfunction in a cohort of older, inpatient women, and to examine any associated health or sociodemographic factors. METHODS: In this cross-sectional, observational study, 50 older women admitted to a subacute hospital completed the Body Shape Questionnaire (BSQ-34), Geriatric Depression Screen (GDS), and Geriatric Anxiety Index (GAI). Additional sociodemographic and health-related data including body mass index (BMI) were collected on all participants. Data were first analysed to determine the prevalence of body image dysfunction. To examine factors significantly associated with body image impairment, partial correlation analyses were initially performed between BSQ-34 score and included variables, followed by stepwise regression analysis undertaken to determine significantly contributing independent variables. RESULTS: Only three out of 50 women displayed body image dysfunction using suggested cut-off scores from the BSQ-34, giving a prevalence rate of only 6%. After controlling for multiple variables however, both higher GDS score and higher BMI were found to be significantly and independently associated with poorer body image, with the strongest association being between higher BSQ-34 score and higher BMI (Spearman rank r = 0.455, P < 0.001). Furthermore, when high BMI and depression occurred together, this association was even greater, accounting for over 50% of the impact on body image scores (P = 0.0001). CONCLUSION: For this small cohort of older, inpatient women, rates of body image dysfunction were low. There did however appear to be an association between poorer body image and higher BMI and depression rates in the group, which may be worth exploring further in less frail, community-dwelling cohorts.
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Ansiedad/epidemiología , Imagen Corporal/psicología , Índice de Masa Corporal , Depresión/epidemiología , Pacientes Internos/psicología , Anciano , Estudios de Cohortes , Estudios Transversales , Demografía , Femenino , Humanos , Pacientes Internos/estadística & datos numéricos , Factores SociológicosRESUMEN
BACKGROUND: Mathematics and Phy sics-based simulation models have the potential to help interpret and encapsulate biological phenomena in a computable and reproducible form. Similarly, comprehensive descriptions of such models help to ensure that such models are accessible, discoverable, and reusable. To this end, researchers have developed tools and standards to encode mathematical models of biological systems enabling reproducibility and reuse, tools and guidelines to facilitate semantic description of mathematical models, and repositories in which to archive, share, and discover models. Scientists can leverage these resources to investigate specific questions and hypotheses in a more efficient manner. RESULTS: We have comprehensively annotated a cohort of models with biological semantics. These annotated models are freely available in the Physiome Model Repository (PMR). To demonstrate the benefits of this approach, we have developed a web-based tool which enables users to discover models relevant to their work, with a particular focus on epithelial transport. Based on a semantic query, this tool will help users discover relevant models, suggesting similar or alternative models that the user may wish to explore or use. CONCLUSION: The semantic annotation and the web tool we have developed is a new contribution enabling scientists to discover relevant models in the PMR as candidates for reuse in their own scientific endeavours. This approach demonstrates how semantic web technologies and methodologies can contribute to biomedical and clinical research. The source code and links to the web tool are available at https://github.com/dewancse/model-discovery-tool.
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Modelos Biológicos , Semántica , Humanos , Modelación Específica para el Paciente , Reproducibilidad de los Resultados , Programas InformáticosRESUMEN
BACKGROUND: Falls are a leading reason for older people presenting to the emergency department (ED), and many experience further falls. Little evidence exists to guide secondary prevention in this population. This randomised controlled trial (RCT) investigated whether a 6-month telephone-based patient-centred program-RESPOND-had an effect on falls and fall injuries in older people presenting to the ED after a fall. METHODS AND FINDINGS: Community-dwelling people aged 60-90 years presenting to the ED with a fall and planned for discharge home within 72 hours were recruited from two EDs in Australia. Participants were enrolled if they could walk without hands-on assistance, use a telephone, and were free of cognitive impairment (Mini-Mental State Examination > 23). Recruitment occurred between 1 April 2014 and 29 June 2015. Participants were randomised to receive either RESPOND (intervention) or usual care (control). RESPOND comprised (1) home-based risk assessment; (2) 6 months telephone-based education, coaching, goal setting, and support for evidence-based risk factor management; and (3) linkages to existing services. Primary outcomes were falls and fall injuries in the 12-month follow-up. Secondary outcomes included ED presentations, hospital admissions, fractures, death, falls risk, falls efficacy, and quality of life. Assessors blind to group allocation collected outcome data via postal calendars, telephone follow-up, and hospital records. There were 430 people in the primary outcome analysis-217 randomised to RESPOND and 213 to control. The mean age of participants was 73 years; 55% were female. Falls per person-year were 1.15 in the RESPOND group and 1.83 in the control (incidence rate ratio [IRR] 0.65 [95% CI 0.43-0.99]; P = 0.042). There was no significant difference in fall injuries (IRR 0.81 [0.51-1.29]; P = 0.374). The rate of fractures was significantly lower in the RESPOND group compared with the control (0.05 versus 0.12; IRR 0.37 [95% CI 0.15-0.91]; P = 0.03), but there were no significant differences in other secondary outcomes between groups: ED presentations, hospitalisations or falls risk, falls efficacy, and quality of life. There were two deaths in the RESPOND group and one in the control group. No adverse events or unintended harm were reported. Limitations of this study were the high number of dropouts (n = 93); possible underreporting of falls, fall injuries, and hospitalisations across both groups; and the relatively small number of fracture events. CONCLUSIONS: In this study, providing a telephone-based, patient-centred falls prevention program reduced falls but not fall injuries, in older people presenting to the ED with a fall. Among secondary outcomes, only fractures reduced. Adopting patient-centred strategies into routine clinical practice for falls prevention could offer an opportunity to improve outcomes and reduce falls in patients attending the ED. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ACTRN12614000336684).
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Accidentes por Caídas/prevención & control , Servicio de Urgencia en Hospital , Educación del Paciente como Asunto/métodos , Atención Dirigida al Paciente/métodos , Factores de Edad , Anciano , Anciano de 80 o más Años , Australia , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Apoyo Social , Teléfono , Factores de Tiempo , Resultado del TratamientoRESUMEN
Cyanobacterial blooms are an increasing threat to water quality and global water security caused by the nutrient enrichment of freshwaters. There is also a broad consensus that blooms are increasing with global warming, but the impacts of other concomitant environmental changes, such as an increase in extreme rainfall events, may affect this response. One of the potential effects of high rainfall events on phytoplankton communities is greater loss of biomass through hydraulic flushing. Here we used a shallow lake mesocosm experiment to test the combined effects of: warming (ambient vs. +4°C increase), high rainfall (flushing) events (no events vs. seasonal events) and nutrient loading (eutrophic vs. hypertrophic) on total phytoplankton chlorophyll-a and cyanobacterial abundance and composition. Our hypotheses were that: (a) total phytoplankton and cyanobacterial abundance would be higher in heated mesocosms; (b) the stimulatory effects of warming on cyanobacterial abundance would be enhanced in higher nutrient mesocosms, resulting in a synergistic interaction; (c) the recovery of biomass from flushing induced losses would be quicker in heated and nutrient-enriched treatments, and during the growing season. The results supported the first and, in part, the third hypotheses: total phytoplankton and cyanobacterial abundance increased in heated mesocosms with an increase in common bloom-forming taxa-Microcystis spp. and Dolichospermum spp. Recovery from flushing was slowest in the winter, but unaffected by warming or higher nutrient loading. Contrary to the second hypothesis, an antagonistic interaction between warming and nutrient enrichment was detected for both cyanobacteria and chlorophyll-a demonstrating that ecological surprises can occur, dependent on the environmental context. While this study highlights the clear need to mitigate against global warming, oversimplification of global change effects on cyanobacteria should be avoided; stressor gradients and seasonal effects should be considered as important factors shaping the response.
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Cianobacterias , Fitoplancton , Eutrofización , Lagos , NutrientesRESUMEN
BACKGROUND: Little is known about doctors' decision-making patterns when using Advance Care Directives (ACDs), particularly for older patients in Australia and New Zealand. AIMS: To determine the level of agreement among Australian and New Zealand doctors' decisions when using ACDs to guide treatment decisions for older patients. To evaluate factors that may affect decision-making including doctors' demographics, vignette complexity and Advance Care Directive (ACD) content. METHODS: In December 2016-January 2017, a survey was distributed to doctors working within one tertiary hospital network in Melbourne and to doctors registered with the Australian and New Zealand Society of Geriatric Medicine. The survey comprised of three vignettes (1, 2, 3) presented with deidentified versions of genuine ACDs (A and B) volunteered by community members via a tertiary hospital ACD service. RESULTS: Five hundred and sixty doctors submitted completed surveys. The level of agreement between doctors when using ACDs varied by vignette complexity, ACD content, doctor speciality (P = 0.006 vignette 1 ACD A, P = 0.04 vignette 1 ACD B, P = 0.04 vignette 2 ACD A, P = 0.04 vignette 3 ACD B) and doctor seniority (P = 0.04 vignette 1 ACD A, P < 0.0001 vignette 2 ACD A). Australian and New Zealand doctors are infrequently exposed to ACDs in their work, 30% did not know the legal status of ACDs and majority of the cohort requested more education on ACDs. CONCLUSION: Despite the presence of an ACD, the level of agreement on treatment decisions for older patients when using ACDs varies by vignette complexity, ACD content, speciality and seniority of doctors.
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Directivas Anticipadas , Toma de Decisiones Clínicas , Conocimientos, Actitudes y Práctica en Salud , Cuidados Paliativos/métodos , Médicos/estadística & datos numéricos , Australia , Femenino , Humanos , Masculino , Nueva Zelanda , Encuestas y CuestionariosRESUMEN
BACKGROUND: RESPOND is a telephone-based falls prevention program for older people who present to a hospital emergency department (ED) with a fall. A randomised controlled trial (RCT) found RESPOND to be effective at reducing the rate of falls and fractures, compared with usual care, but not fall injuries or hospitalisations. This process evaluation aimed to determine whether RESPOND was implemented as planned, and identify implementation barriers and facilitators. METHODS: A mixed-methods evaluation was conducted alongside the RCT. Evaluation participants were the RESPOND intervention group (n = 263) and the clinicians delivering RESPOND (n = 7). Evaluation data were collected from participant recruitment and intervention records, hospital administrative records, audio-recordings of intervention sessions, and participant questionnaires. The Rochester Participatory Decision-Making Scale (RPAD) was used to evaluate person-centredness (score range 0 (worst) - 9 (best)). Process factors were compared with pre-specified criteria to determine implementation fidelity. Six focus groups were held with participants (n = 41), and interviews were conducted with RESPOND clinicians (n = 6). Quantitative data were analysed descriptively and qualitative data thematically. Barriers and facilitators to implementation were mapped to the 'Capability, Opportunity, Motivation - Behaviour' (COM-B) behaviour change framework. RESULTS: RESPOND was implemented at a lower dose than the planned 10 h over 6 months, with a median (IQR) of 2.9 h (2.1, 4). The majority (76%) of participants received their first intervention session within 1 month of hospital discharge with a median (IQR) of 18 (12, 30) days. Clinicians delivered the program in a person-centred manner with a median (IQR) RPAD score of 7 (6.5, 7.5) and 87% of questionnaire respondents were satisfied with the program. The reports from participants and clinicians suggested that implementation was facilitated by the use of positive and personally relevant health messages. Complex health and social issues were the main barriers to implementation. CONCLUSIONS: RESPOND was person-centred and reduced falls and fractures at a substantially lower dose, using fewer resources, than anticipated. However, the low dose delivered may account for the lack of effect on falls injuries and hospitalisations. The results from this evaluation provide detailed information to guide future implementation of RESPOND or similar programs. TRIAL REGISTRATION: This study was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12614000336684 (27 March 2014).
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Prevención de Accidentes , Accidentes por Caídas/prevención & control , Atención Dirigida al Paciente/métodos , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Grupos Focales , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , TeléfonoRESUMEN
Background: Klebsiella pneumoniae is a leading cause of extended-spectrum ß-lactamase (ESBL)-producing hospital-associated infections, for which elderly patients are at increased risk. Methods: We conducted a 1-year prospective cohort study, in which a third of patients admitted to 2 geriatric wards in a specialized hospital were recruited and screened for carriage of K. pneumoniae by microbiological culture. Clinical isolates were monitored via the hospital laboratory. Colonizing and clinical isolates were subjected to whole-genome sequencing and antimicrobial susceptibility testing. Results: K. pneumoniae throat carriage prevalence was 4.1%, rectal carriage 10.8%, and ESBL carriage 1.7%, and the incidence of K. pneumoniae infection was 1.2%. The isolates were diverse, and most patients were colonized or infected with a unique phylogenetic lineage, with no evidence of transmission in the wards. ESBL strains carried blaCTX-M-15 and belonged to clones associated with hospital-acquired ESBL infections in other countries (sequence type [ST] 29, ST323, and ST340). One also carried the carbapenemase blaIMP-26. Genomic and epidemiological data provided evidence that ESBL strains were acquired in the referring hospital. Nanopore sequencing also identified strain-to-strain transmission of a blaCTX-M-15 FIBK/FIIK plasmid in the referring hospital. Conclusions: The data suggest the major source of K. pneumoniae was the patient's own gut microbiome, but ESBL strains were acquired in the referring hospital. This highlights the importance of the wider hospital network to understanding K. pneumoniae risk and infection prevention. Rectal screening for ESBL organisms on admission to geriatric wards could help inform patient management and infection control in such facilities.
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Portador Sano/microbiología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Klebsiella pneumoniae/aislamiento & purificación , Anciano , Anciano de 80 o más Años , Infección Hospitalaria/diagnóstico , Femenino , Servicios de Salud para Ancianos , Unidades Hospitalarias , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Klebsiella pneumoniae/efectos de los fármacos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Blooms of cyanobacteria are a current threat to global water security that is expected to increase in the future because of increasing nutrient enrichment, increasing temperature and extreme precipitation in combination with prolonged drought. However, the responses to multiple stressors, such as those above, are often complex and there is contradictory evidence as to how they may interact. Here we used broad scale data from 494 lakes in central and northern Europe, to assess how cyanobacteria respond to nutrients (phosphorus), temperature and water retention time in different types of lakes. Eight lake types were examined based on factorial combinations of major factors that determine phytoplankton composition and sensitivity to nutrients: alkalinity (low and medium-high), colour (clear and humic) and mixing intensity (polymictic and stratified). In line with expectations, cyanobacteria increased with temperature and retention time in five of the eight lake types. Temperature effects were greatest in lake types situated at higher latitudes, suggesting that lakes currently not at risk could be affected by warming in the future. However, the sensitivity of cyanobacteria to temperature, retention time and phosphorus varied among lake types highlighting the complex responses of lakes to multiple stressors. For example, in polymictic, medium-high alkalinity, humic lakes cyanobacteria biovolume was positively explained by retention time and a synergy between TP and temperature, while in polymictic, medium-high alkalinity, clear lakes only retention time was identified as an explanatory variable. These results show that, although climate change will need to be accounted for when managing the risk of cyanobacteria in lakes, a "one-size fits-all" approach is not appropriate. When forecasting the response of cyanobacteria to future environmental change, including changes caused by climate and local management, it will be important to take this differential sensitivity of lakes into account.
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Cianobacterias , Lagos/microbiología , Cambio Climático , Ambiente , Europa (Continente) , Fósforo/análisis , FitoplanctonRESUMEN
Critical care, like many healthcare areas, is under a dual assault from significantly increasing demographic and economic pressures. Intensive care unit (ICU) patients are highly variable in response to treatment, and increasingly aging populations mean ICUs are under increasing demand and their cohorts are increasingly ill. Equally, patient expectations are growing, while the economic ability to deliver care to all is declining. Better, more productive care is thus the big challenge. One means to that end is personalised care designed to manage the significant inter- and intra-patient variability that makes the ICU patient difficult. Thus, moving from current "one size fits all" protocolised care to adaptive, model-based "one method fits all" personalised care could deliver the required step change in the quality, and simultaneously the productivity and cost, of care. Computer models of human physiology are a unique tool to personalise care, as they can couple clinical data with mathematical methods to create subject-specific models and virtual patients to design new, personalised and more optimal protocols, as well as to guide care in real-time. They rely on identifying time varying patient-specific parameters in the model that capture inter- and intra-patient variability, the difference between patients and the evolution of patient condition. Properly validated, virtual patients represent the real patients, and can be used in silico to test different protocols or interventions, or in real-time to guide care. Hence, the underlying models and methods create the foundation for next generation care, as well as a tool for safely and rapidly developing personalised treatment protocols over large virtual cohorts using virtual trials. This review examines the models and methods used to create virtual patients. Specifically, it presents the models types and structures used and the data required. It then covers how to validate the resulting virtual patients and trials, and how these virtual trials can help design and optimise clinical trial. Links between these models and higher order, more complex physiome models are also discussed. In each section, it explores the progress reported up to date, especially on core ICU therapies in glycemic, circulatory and mechanical ventilation management, where high cost and frequency of occurrence provide a significant opportunity for model-based methods to have measurable clinical and economic impact. The outcomes are readily generalised to other areas of medical care.
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Simulación por Computador , Cuidados Críticos/métodos , Modelos Biológicos , Medicina de Precisión/métodos , Estudios de Cohortes , Humanos , Fenómenos FisiológicosRESUMEN
The role of computational modeling for biomechanics research and related clinical care will be increasingly prominent. The biomechanics community has been developing computational models routinely for exploration of the mechanics and mechanobiology of diverse biological structures. As a result, a large array of models, data, and discipline-specific simulation software has emerged to support endeavors in computational biomechanics. Sharing computational models and related data and simulation software has first become a utilitarian interest, and now, it is a necessity. Exchange of models, in support of knowledge exchange provided by scholarly publishing, has important implications. Specifically, model sharing can facilitate assessment of reproducibility in computational biomechanics and can provide an opportunity for repurposing and reuse, and a venue for medical training. The community's desire to investigate biological and biomechanical phenomena crossing multiple systems, scales, and physical domains, also motivates sharing of modeling resources as blending of models developed by domain experts will be a required step for comprehensive simulation studies as well as the enhancement of their rigor and reproducibility. The goal of this paper is to understand current perspectives in the biomechanics community for the sharing of computational models and related resources. Opinions on opportunities, challenges, and pathways to model sharing, particularly as part of the scholarly publishing workflow, were sought. A group of journal editors and a handful of investigators active in computational biomechanics were approached to collect short opinion pieces as a part of a larger effort of the IEEE EMBS Computational Biology and the Physiome Technical Committee to address model reproducibility through publications. A synthesis of these opinion pieces indicates that the community recognizes the necessity and usefulness of model sharing. There is a strong will to facilitate model sharing, and there are corresponding initiatives by the scientific journals. Outside the publishing enterprise, infrastructure to facilitate model sharing in biomechanics exists, and simulation software developers are interested in accommodating the community's needs for sharing of modeling resources. Encouragement for the use of standardized markups, concerns related to quality assurance, acknowledgement of increased burden, and importance of stewardship of resources are noted. In the short-term, it is advisable that the community builds upon recent strategies and experiments with new pathways for continued demonstration of model sharing, its promotion, and its utility. Nonetheless, the need for a long-term strategy to unify approaches in sharing computational models and related resources is acknowledged. Development of a sustainable platform supported by a culture of open model sharing will likely evolve through continued and inclusive discussions bringing all stakeholders at the table, e.g., by possibly establishing a consortium.
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Simulación por Computador , Fenómenos Mecánicos , Fenómenos BiomecánicosRESUMEN
Biomedical research and clinical practice are struggling to cope with the growing complexity that the progress of health care involves. The most challenging diseases, those with the largest socioeconomic impact (cardiovascular conditions; musculoskeletal conditions; cancer; metabolic, immunity, and neurodegenerative conditions), are all characterized by a complex genotype-phenotype interaction and by a "systemic" nature that poses a challenge to the traditional reductionist approach. In 2005 a small group of researchers discussed how the vision of computational physiology promoted by the Physiome Project could be translated into clinical practice and formally proposed the term Virtual Physiological Human. Our knowledge about these diseases is fragmentary, as it is associated with molecular and cellular processes on the one hand and with tissue and organ phenotype changes (related to clinical symptoms of disease conditions) on the other. The problem could be solved if we could capture all these fragments of knowledge into predictive models and then compose them into hypermodels that help us tame the complexity that such systemic behavior involves. In 2005 this was simply not possible-the necessary methods and technologies were not available. Now, 10 years later, it seems the right time to reflect on the original vision, the results achieved so far, and what remains to be done.
Asunto(s)
Arritmias Cardíacas/fisiopatología , Asma/fisiopatología , Simulación por Computador , Sistema de Conducción Cardíaco/fisiopatología , Modelación Específica para el Paciente/tendencias , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Interfaz Usuario-Computador , HumanosRESUMEN
Objective: to investigate a high-intensity functional exercise (HIFE) group in hospitalised older adults. Design: assessor-blinded, randomised-controlled trial. Setting: sub-acute wards at a metropolitan rehabilitation hospital. Participants: older adults ≥65 years (n = 468) able to stand with minimum assistance or less from a chair and follow instructions. Intervention: 'group' participants were offered a standing HIFE group three times a week and individual physiotherapy sessions twice a week. Control participants were offered daily individual physiotherapy sessions. Main outcome measures: the primary outcome measure was the Elderly Mobility Scale (EMS). Secondary measures included the Berg Balance Scale, gait speed, Timed Up and Go Test, falls, length of stay and discharge destination. Results: participants' mean age was 84.3 (7.1) years and 61% were female. There was no difference between groups for the improvement in EMS from admission to discharge (effect size -0.07, 95% confidence interval: -0.26 to 0.11, P = 0.446) and no difference in discharge destination, P = 0.904. Therapists saved 31-205 min/week treating group participants compared with control participants. Conclusion: the results suggest that a HIFE group programme combined with individual physiotherapy may improve mobility to a similar extent to individual physiotherapy alone in hospitalised older adults. Providing physiotherapy in a group setting resulted in increased therapist efficiency. A high-intensity exercise group with individual physiotherapy may be an effective and efficient method to provide care to older inpatients.