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1.
Nature ; 604(7906): 525-533, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388223

RESUMEN

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.


Asunto(s)
Encéfalo , Longevidad , Estatura , Encéfalo/anatomía & histología , Humanos , Imagen por Resonancia Magnética/métodos , Neuroimagen
2.
Nature ; 585(7824): E6, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32826959

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Nature ; 584(7820): 201-204, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32788739

RESUMEN

The extreme astrophysical processes and conditions that characterize the early Universe are expected to result in young galaxies that are dynamically different from those observed today1-5. This is because the strong effects associated with galaxy mergers and supernova explosions would lead to most young star-forming galaxies being dynamically hot, chaotic and strongly unstable1,2. Here we report the presence of a dynamically cold, but highly star-forming, rotating disk in a galaxy at redshift6 z = 4.2, when the Universe was just 1.4 billion years old. Galaxy SPT-S J041839-4751.9 is strongly gravitationally lensed by a foreground galaxy at z = 0.263, and it is a typical dusty starburst, with global star-forming7 and dust properties8 that are in agreement with current numerical simulations9 and observations10. Interferometric imaging at a spatial resolution of about 60 parsecs reveals a ratio of rotational to random motions of 9.7 ± 0.4, which is at least four times larger than that expected from any galaxy evolution model at this epoch1-5 but similar to the ratios of spiral galaxies in the local Universe11. We derive a rotation curve with the typical shape of nearby massive spiral galaxies, which demonstrates that at least some young galaxies are dynamically akin to those observed in the local Universe, and only weakly affected by extreme physical processes.

4.
Nature ; 585(7823): 39-42, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32879500

RESUMEN

Cosmological models in which dark matter consists of cold elementary particles predict that the dark halo population should extend to masses many orders of magnitude below those at which galaxies can form1-3. Here we report a cosmological simulation of the formation of present-day haloes over the full range of observed halo masses (20 orders of magnitude) when dark matter is assumed to be in the form of weakly interacting massive particles of mass approximately 100 gigaelectronvolts. The simulation has a full dynamic range of 30 orders of magnitude in mass and resolves the internal structure of hundreds of Earth-mass haloes in as much detail as it does for hundreds of rich galaxy clusters. We find that halo density profiles are universal over the entire mass range and are well described by simple two-parameter fitting formulae4,5. Halo mass and concentration are tightly related in a way that depends on cosmology and on the nature of the dark matter. For a fixed mass, the concentration is independent of the local environment for haloes less massive than those of typical galaxies. Haloes over the mass range of 10-3 to 1011 solar masses contribute about equally (per logarithmic interval) to the luminosity produced by dark matter annihilation, which we find to be smaller than all previous estimates by factors ranging up to one thousand3.

5.
Psychol Med ; 54(5): 1004-1015, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37905705

RESUMEN

BACKGROUND: We investigated disparities in the clinical management of self-harm following hospital presentation with self-harm according to level of socio-economic deprivation (SED) in England. METHODS: 108 092 presentations to hospitals (by 57 306 individuals) after self-harm in the Multicenter Study of Self-harm spanning 17 years. Area-level SED was based on the English Index of Multiple Deprivation. Information about indicators of clinical care was obtained from each hospital's self-harm monitoring systems. We assessed the associations of SED with indicators of care using mixed effect models. RESULTS: Controlling for confounders, psychosocial assessment and admission to a general medical ward were less likely for presentations by patients living in more deprived areas relative to presentations by patients from the least deprived areas. Referral for outpatient mental health care was less likely for presentations by patients from the two most deprived localities (most deprived: adjusted odd ratio [aOR] 0.77, 95% CI 0.71-0.83, p < 0.0001; 2nd most deprived: aOR 0.80, 95% CI 0.74-0.87, p < 0.0001). Referral to substance use services and 'other' services increased with increased SED. Overall, referral for aftercare was less likely following presentations by patients living in the two most deprived areas (most deprived: aOR 0.85, 95% CI 0.78-0.92, p < 0.0001; 2nd most deprived: aOR 0.86, 95% CI 0.79-0.94, p = 0.001). CONCLUSIONS: SED is associated with differential care for patients who self-harm in England. Inequalities in care may exacerbate the risk of adverse outcomes in this disadvantaged population. Further work is needed to understand the reasons for these differences and ways of providing more equitable care.


Asunto(s)
Conducta Autodestructiva , Humanos , Conducta Autodestructiva/epidemiología , Conducta Autodestructiva/terapia , Conducta Autodestructiva/psicología , Inglaterra/epidemiología , Hospitalización , Pobreza , Hospitales
6.
J Theor Biol ; 581: 111737, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38280544

RESUMEN

Xylem-limited bacterial pathogens cause some of the most destructive plant diseases. Though imposed measures to control these pathogens are generally ineffective, even among susceptible taxa, some hosts can limit bacterial loads and symptom expression. Mechanisms by which this resistance is achieved are poorly understood. In particular, it is still unknown how differences in vascular structure may influence biofilm growth and spread within a host. To address this, we developed a novel theoretical framework to describe biofilm behaviour within xylem vessels, adopting a polymer-based modelling approach. We then parameterised the model to investigate the relevance of xylem vessel diameters on Xylella fastidiosa resistance among olive cultivars. The functionality of all vessels was severely reduced under infection, with hydraulic flow reductions of 2-3 orders of magnitude. However, results suggest wider vessels act as biofilm incubators; allowing biofilms to develop over a long time while still transporting them through the vasculature. By contrast, thinner vessels become blocked much earlier, limiting biofilm spread. Using experimental data on vessel diameter distributions, we were able to determine that a mechanism of resistance in the olive cultivar Leccino is a relatively low abundance of the widest vessels, limiting X. fastidiosa spread.


Asunto(s)
Olea , Xylella , Olea/metabolismo , Olea/microbiología , Biopelículas , Xilema , Enfermedades de las Plantas/microbiología , Modelos Teóricos
7.
Pediatr Transplant ; 28(1): e14649, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38013204

RESUMEN

BACKGROUND: Recent studies demonstrate high offer decline and organ non-utilization rates are associated with increased pediatric heart transplant waitlist mortality. We sought to determine which donor, candidate, and offer specific variables most importantly influenced these decisions using only data available at the time of each offer. METHODS: Retrospective review of pediatric (<18 years) heart donor offers made to pediatric candidates in the United States between 2010 and 2020. In addition to standard donor, candidate, and offer data available in UNOS, we extracted objective and qualitative valvar and myocardial function data from all available donor echocardiogram reports. RESULTS: During the study period, 5625 pediatric donor hearts produced 30 156 offers to 4905 unique candidates, of which 88.7% of all offers were declined and 39.2% of organs were not utilized by pediatric waitlisted candidates. Of the 60.8% utilized hearts, 89.7% had a 'cumulatively' normal echocardiogram at the time of offer acceptance; 62.9% of hearts not utilized for a pediatric candidate also had a cumulatively normal final echocardiogram. Random forest and logistic regression modeling demonstrated good predictive performance (AUROC ≥0.83) of likelihood to accept when utilizing donor, candidate, and offer specific variables. SHAP variable importance scores demonstrated number of prior offer declines and candidate institution's prior year acceptance rates as the two most important variables influencing offer decisions. CONCLUSIONS: Behavioral economics appear to play a significant role in pediatric heart transplant candidate institutions' acceptance practices, even when considering the arguably healthier pediatric donor population. Removal of prior institution's decisions from DonorNet may help increase donor utilization.


Asunto(s)
Trasplante de Corazón , Obtención de Tejidos y Órganos , Humanos , Niño , Estados Unidos , Donantes de Tejidos , Selección de Donante , Estudios Retrospectivos , Listas de Espera
8.
J Intellect Disabil Res ; 68(2): 113-127, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37740553

RESUMEN

BACKGROUND: 3q29 deletion syndrome (3q29del) is associated with a significantly increased risk for neurodevelopmental and neuropsychiatric phenotypes. Mild to moderate intellectual disability (ID) is common in this population, and previous work by our team identified substantial deficits in adaptive behaviour. However, the full profile of adaptive function in 3q29del has not been described nor has it been compared with other genomic syndromes associated with elevated risk for neurodevelopmental and neuropsychiatric phenotypes. METHODS: Individuals with 3q29del (n = 32, 62.5% male) were evaluated using the Vineland Adaptive Behaviour Scales, Third Edition, Comprehensive Parent/Caregiver Form (Vineland-3). We explored the relationship between adaptive behaviour and cognitive function, executive function, and neurodevelopmental and neuropsychiatric comorbidities in our 3q29del study sample, and we compared subjects with 3q29del with published data on fragile X syndrome, 22q11.2 deletion syndrome and 16p11.2 deletion and duplication syndromes. RESULTS: Individuals with 3q29del had global deficits in adaptive behaviour that were not driven by specific weaknesses in any given domain. Individual neurodevelopmental and neuropsychiatric diagnoses had a small effect on adaptive behaviour, and the cumulative number of comorbid diagnoses was significantly negatively associated with Vineland-3 performance. Both cognitive ability and executive function were significantly associated with adaptive behaviour, and executive function was a better predictor of Vineland-3 performance than cognitive ability. Finally, the severity of adaptive behaviour deficits in 3q29del was distinct from previously published data on comparable genomic disorders. CONCLUSIONS: Individuals with 3q29del have significant deficits in adaptive behaviour, affecting all domains assessed by the Vineland-3. Executive function is a better predictor of adaptive behaviour than cognitive ability in this population and suggests that interventions targeting executive function may be an effective therapeutic strategy.


Asunto(s)
Síndrome del Cromosoma X Frágil , Discapacidad Intelectual , Humanos , Masculino , Femenino , Discapacidad Intelectual/psicología , Función Ejecutiva , Cognición , Síndrome del Cromosoma X Frágil/complicaciones , Adaptación Psicológica
10.
J Intellect Disabil Res ; 67(3): 216-227, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35297118

RESUMEN

BACKGROUND: 3q29 deletion syndrome is associated with mild to moderate intellectual disability as well as comorbid psychopathology such as ADHD, anxiety, ASD and schizophrenia. A greater understanding of specific profiles that could increase risk for psychopathology is necessary in order to best understand and support individuals with 3q29 deletion syndrome. The goal of this study was to thus carefully outline the strengths and weaknesses of these individuals. A second goal was to ask whether the cognitive impact of the deletion predicted psychopathology in other domains. METHODS: We systematically evaluated cognitive ability, adaptive behaviour and psychopathology in 32 individuals with the canonical 3q29 deletion using gold-standard instruments and a standardised phenotyping protocol. RESULTS: Mean full scale IQ was 73 (range 40-99). Verbal subtest score (mean 80, range 31-106) was slightly higher and had a greater range than non-verbal subtest score (mean 75, range 53-98). Spatial ability was evaluated in a subset (n = 24) and was lower than verbal and non-verbal ability (mean 71, range 34-108). There was an average 14-point difference between verbal and non-verbal subset scores; 60% of the time the verbal subset score was higher than the non-verbal subset score. Study subjects with a verbal ability subtest score lower than the non-verbal subtest score were four times more likely to have a diagnosis of intellectual disability (suggestive, P value 0.07). The age at which a child first spoke two-word phrases was strongly associated with measures of verbal ability (P value 2.56e-07). Cognitive ability was correlated with adaptive behaviour measures (correlation 0.42, P value 0.02). However, although group means found equivalent scores, there was, on average, a 10-point gap between these skills (range -33 to 33), in either direction, in about 50% of the sample, suggesting that cognitive measures only partially inform adaptive ability. Cognitive ability scores did not have any significant relationship to cumulative burden of psychopathology nor to individual neurodevelopmental or psychiatric diagnoses. CONCLUSIONS: Individuals with 3q29 deletion syndrome have a complex pattern of cognitive disability. Two-thirds of individuals with the deletion will exhibit significant strength in verbal ability; this may mask deficits in non-verbal reasoning, leading to an overestimation of overall ability. Deficits in verbal ability may be the driver of intellectual disability diagnosis. Cognitive ability is not a strong indicator of other neurodevelopmental or psychiatric impairment; thus, individuals with 3q29 deletion syndrome who exhibit IQ scores within the normal range should receive all recommended behavioural evaluations.


Asunto(s)
Discapacidad Intelectual , Esquizofrenia , Niño , Humanos , Discapacidad Intelectual/psicología , Síndrome , Psicopatología , Cognición
11.
Vet Dermatol ; 34(3): 175-208, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37154488

RESUMEN

BACKGROUND: Allergic skin diseases are common in horses worldwide. The most common causes are insect bites and environmental allergens. OBJECTIVES: To review the current literature and provide consensus on pathogenesis, diagnosis, treatment and prevention. MATERIALS AND METHODS: The authors reviewed the literature up to November 2022. Results were presented at North America Veterinary Dermatology Forum (2021) and European Veterinary Dermatology Congress (2021). The report was available to member organisations of the World Association for Veterinary Dermatology for feedback. CONCLUSIONS AND CLINICAL RELEVANCE: Insect bite hypersensitivity (IBH) is the best characterised allergic skin disease. An immunoglobulin (Ig)E response against Culicoides salivary antigens is widely documented. Genetics and environmental factors play important roles. Tests with high sensitivity and specificity are lacking, and diagnosis of IBH is based on clinical signs, seasonality and response to insect control. Eosinophils, interleukin (IL)-5 and IL-31 are explored as therapeutic targets. Presently, the most effective treatment is insect avoidance. Existing evidence does not support allergen-specific immunotherapy (ASIT) using commercially available extracts of Culicoides. Hypersensitivity to environmental allergens (atopic dermatitis) is the next most common allergy. A role for IgE is supported by serological investigation, skin test studies and positive response to ASIT. Prospective, controlled, randomised studies are limited, and treatment relies largely on glucocorticoids, antihistamines and ASIT based on retrospective studies. Foods are known triggers for urticaria, yet their role in pruritic dermatitis is unknown. Recurrent urticaria is common in horses, yet our understanding is limited and focussed on IgE and T-helper 2 cell response. Prospective, controlled studies on treatments for urticaria are lacking. Glucocorticoids and antihistamines are primary reported treatments.


Asunto(s)
Ceratopogonidae , Dermatitis Atópica , Dermatología , Enfermedades de los Caballos , Hipersensibilidad , Mordeduras y Picaduras de Insectos , Urticaria , Animales , Caballos , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/terapia , Dermatitis Atópica/veterinaria , Estudios Retrospectivos , Estudios Prospectivos , Inmunoglobulina E , Hipersensibilidad/veterinaria , Alérgenos , Urticaria/veterinaria , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/terapia , Mordeduras y Picaduras de Insectos/complicaciones , Mordeduras y Picaduras de Insectos/veterinaria
12.
Anaesthesia ; 77(2): 201-212, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34724710

RESUMEN

The Earth's mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists' education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references.


Asunto(s)
Anestesia/normas , Anestesiólogos/normas , Conferencias de Consenso como Asunto , Exposición a Riesgos Ambientales/normas , Calentamiento Global/prevención & control , Sociedades Médicas/normas , Anestesia/tendencias , Anestesiólogos/tendencias , Técnica Delphi , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/prevención & control , Salud Global/normas , Salud Global/tendencias , Humanos , Escocia
13.
Int J Environ Health Res ; 32(3): 579-594, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32631102

RESUMEN

Handwashing with soap at critical times helps prevent diarrhoeal diseases. Changing handwashing practices through behaviour change communication remains a challenge. This study designed and tested a scalable intervention to promote handwashing with soap. A cluster-randomised, controlled trial compared our intervention against standard practice. Subjects were men, women and children in 14 villages in Cross-River state, Nigeria. The primary outcome was the proportion of observed key events on which hands were washed with soap. Binomial regression analysis calculated prevalence differences between study arms. The intervention had minimal effect on the primary outcome (+2.4%, p = 0.096). The intervention was associated with increased frequency of handwashes without soap before food contact (+13%, p = 0.017). The intervention failed to produce significant changes in handwashing with soap at key times. The low dose delivered (two contact points) may have increased scalability at the cost of effectiveness, particularly in the challenging context of inconvenient water access.


Asunto(s)
Desinfección de las Manos , Jabones , Niño , Diarrea/epidemiología , Diarrea/prevención & control , Femenino , Humanos , Masculino , Nigeria , Población Rural
14.
Neuroimage ; 225: 117480, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33099009

RESUMEN

The brain can be modelled as a network with nodes and edges derived from a range of imaging modalities: the nodes correspond to spatially distinct regions and the edges to the interactions between them. Whole-brain connectivity studies typically seek to determine how network properties change with a given categorical phenotype such as age-group, disease condition or mental state. To do so reliably, it is necessary to determine the features of the connectivity structure that are common across a group of brain scans. Given the complex interdependencies inherent in network data, this is not a straightforward task. Some studies construct a group-representative network (GRN), ignoring individual differences, while other studies analyse networks for each individual independently, ignoring information that is shared across individuals. We propose a Bayesian framework based on exponential random graph models (ERGM) extended to multiple networks to characterise the distribution of an entire population of networks. Using resting-state fMRI data from the Cam-CAN project, a study on healthy ageing, we demonstrate how our method can be used to characterise and compare the brain's functional connectivity structure across a group of young individuals and a group of old individuals.


Asunto(s)
Teorema de Bayes , Encéfalo/fisiología , Modelos Neurológicos , Red Nerviosa/fisiología , Mapeo Encefálico/métodos , Humanos , Individualidad , Imagen por Resonancia Magnética , Modelos Estadísticos , Vías Nerviosas
15.
Br J Surg ; 108(2): 188-195, 2021 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-33711145

RESUMEN

BACKGROUND: The role of minimally invasive distal pancreatectomy is still unclear, and whether robotic distal pancreatectomy (RDP) offers benefits over laparoscopic distal pancreatectomy (LDP) is unknown because large multicentre studies are lacking. This study compared perioperative outcomes between RDP and LDP. METHODS: A multicentre international propensity score-matched study included patients who underwent RDP or LDP for any indication in 21 European centres from six countries that performed at least 15 distal pancreatectomies annually (January 2011 to June 2019). Propensity score matching was based on preoperative characteristics in a 1 : 1 ratio. The primary outcome was the major morbidity rate (Clavien-Dindo grade IIIa or above). RESULTS: A total of 1551 patients (407 RDP and 1144 LDP) were included in the study. Some 402 patients who had RDP were matched with 402 who underwent LDP. After matching, there was no difference between RDP and LDP groups in rates of major morbidity (14.2 versus 16.5 per cent respectively; P = 0.378), postoperative pancreatic fistula grade B/C (24.6 versus 26.5 per cent; P = 0.543) or 90-day mortality (0.5 versus 1.3 per cent; P = 0.268). RDP was associated with a longer duration of surgery than LDP (median 285 (i.q.r. 225-350) versus 240 (195-300) min respectively; P < 0.001), lower conversion rate (6.7 versus 15.2 per cent; P < 0.001), higher spleen preservation rate (81.4 versus 62.9 per cent; P = 0.001), longer hospital stay (median 8.5 (i.q.r. 7-12) versus 7 (6-10) days; P < 0.001) and lower readmission rate (11.0 versus 18.2 per cent; P = 0.004). CONCLUSION: The major morbidity rate was comparable between RDP and LDP. RDP was associated with improved rates of conversion, spleen preservation and readmission, to the detriment of longer duration of surgery and hospital stay.


Asunto(s)
Laparoscopía , Pancreatectomía/métodos , Procedimientos Quirúrgicos Robotizados , Anciano , Conversión a Cirugía Abierta/estadística & datos numéricos , Femenino , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Laparoscopía/mortalidad , Laparoscopía/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Tempo Operativo , Pancreatectomía/efectos adversos , Pancreatectomía/mortalidad , Puntaje de Propensión , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/mortalidad , Procedimientos Quirúrgicos Robotizados/estadística & datos numéricos , Resultado del Tratamiento
16.
Phys Rev Lett ; 127(18): 186001, 2021 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-34767414

RESUMEN

Understanding the mechanisms of proton energy deposition in matter and subsequent damage formation is fundamental to radiation science. Here we exploit the picosecond (10^{-12} s) resolution of laser-driven accelerators to track ultrafast solvation dynamics for electrons due to proton radiolysis in liquid water (H_{2}O). Comparing these results with modeling that assumes initial conditions similar to those found in photolysis reveals that solvation time due to protons is extended by >20 ps. Supported by magnetohydrodynamic theory this indicates a highly dynamic phase in the immediate aftermath of the proton interaction that is not accounted for in current models.

17.
Philos Trans A Math Phys Eng Sci ; 379(2190): 20200174, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33342380

RESUMEN

By direct measurements of the gas temperature, the Atacama Large Millimeter/submillimeter Array (ALMA) has yielded a new diagnostic tool to study the solar chromosphere. Here, we present an overview of the brightness-temperature fluctuations from several high-quality and high-temporal-resolution (i.e. 1 and 2 s cadence) time series of images obtained during the first 2 years of solar observations with ALMA, in Band 3 and Band 6, centred at around 3 mm (100 GHz) and 1.25 mm (239 GHz), respectively. The various datasets represent solar regions with different levels of magnetic flux. We perform fast Fourier and Lomb-Scargle transforms to measure both the spatial structuring of dominant frequencies and the average global frequency distributions of the oscillations (i.e. averaged over the entire field of view). We find that the observed frequencies significantly vary from one dataset to another, which is discussed in terms of the solar regions captured by the observations (i.e. linked to their underlying magnetic topology). While the presence of enhanced power within the frequency range 3-5 mHz is found for the most magnetically quiescent datasets, lower frequencies dominate when there is significant influence from strong underlying magnetic field concentrations (present inside and/or in the immediate vicinity of the observed field of view). We discuss here a number of reasons which could possibly contribute to the power suppression at around 5.5 mHz in the ALMA observations. However, it remains unclear how other chromospheric diagnostics (with an exception of Hα line-core intensity) are unaffected by similar effects, i.e. they show very pronounced 3-min oscillations dominating the dynamics of the chromosphere, whereas only a very small fraction of all the pixels in the 10 ALMA datasets analysed here show peak power near 5.5 mHz. This article is part of the Theo Murphy meeting issue 'High-resolution wave dynamics in the lower solar atmosphere'.

18.
Anaesthesia ; 76(2): 225-237, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33289066

RESUMEN

We convened a multidisciplinary Working Party on behalf of the Association of Anaesthetists to update the 2011 guidance on the peri-operative management of people with hip fracture. Importantly, these guidelines describe the core aims and principles of peri-operative management, recommending greater standardisation of anaesthetic practice as a component of multidisciplinary care. Although much of the 2011 guidance remains applicable to contemporary practice, new evidence and consensus inform the additional recommendations made in this document. Specific changes to the 2011 guidance relate to analgesia, medicolegal practice, risk assessment, bone cement implantation syndrome and regional review networks. Areas of controversy remain, and we discuss these in further detail, relating to the mode of anaesthesia, surgical delay, blood management and transfusion thresholds, echocardiography, anticoagulant and antiplatelet management and postoperative discharge destination. Finally, these guidelines provide links to supplemental online material that can be used at readers' institutions, key references and UK national guidance about the peri-operative care of people with hip and periprosthetic fractures during the COVID-19 pandemic.


Asunto(s)
Manejo de Caso/normas , Fracturas de Cadera/terapia , Anestesia/normas , COVID-19 , Guías como Asunto , Fracturas de Cadera/cirugía , Humanos , Pandemias , Mejoramiento de la Calidad
19.
Soc Psychiatry Psychiatr Epidemiol ; 56(10): 1903-1911, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33606048

RESUMEN

PURPOSE: Evidence suggests that the distinctive relational qualities of peer support-compared to clinical-patient relationships-can be eroded in regulated healthcare environments. Measurement of fidelity in trials of peer support is lacking. This paper reports the development and testing of a fidelity index for one-to-one peer support in mental health services, designed to assess fidelity to principles that characterise the distinctiveness of peer support. METHODS: A draft index was developed using expert panels of service user researchers and people doing peer support, informed by an evidence-based, peer support principles framework. Two rounds of testing took place in 24 mental health services providing peer support in a range of settings. Fidelity was assessed through interviews with peer workers, their supervisors and people receiving peer support. Responses were tested for spread and internal consistency, independently double rated for inter-rater reliability, with feedback from interviewees and service user researchers used to refine the index. RESULTS: A fidelity index for one-to-one peer support in mental health services was produced with good psychometric properties. Fidelity is assessed in four principle-based domains; building trusting relationships based on shared lived experience; reciprocity and mutuality; leadership, choice and control; building strengths and making connections to community. CONCLUSIONS: The index offers potential to improve the evidence base for peer support in mental health services, enabling future trials to assess fidelity of interventions to peer support principles, and service providers a means of ensuring that peer support retains its distinctive qualities as it is introduced into mental health services.


Asunto(s)
Trastornos Mentales , Servicios de Salud Mental , Consejo , Humanos , Trastornos Mentales/terapia , Grupo Paritario , Psicometría , Reproducibilidad de los Resultados
20.
Dysphagia ; 36(5): 831-841, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33156398

RESUMEN

The mechanisms responsible for aspiration are relatively unknown in patients recovering from acute respiratory failure (ARF) who required mechanical ventilation. Though many conditions may contribute to swallowing dysfunction, alterations in laryngeal structure and swallowing function likely play a role in the development of aspiration. At four university-based tertiary medical centers, we conducted a prospective cohort study of ARF patients who required intensive care and mechanical ventilation for at least 48 h. Within 72 h after extubation, a Fiberoptic Flexible Endoscopic Evaluation of Swallowing (FEES) examination was performed. Univariate and multivariable analyses examined the relationship between laryngeal structure and swallowing function abnormalities. Aspiration was the primary outcome, defined as a Penetration- Aspiration Scale (PAS) score of 6 or greater. Two other salient signs of dysphagia-spillage and residue-were secondary outcomes. A total of 213 patients were included in the final analysis. Aspiration was detected in 70 patients (33%) on at least one bolus. The most commonly aspirated consistency was thin liquids (27%). In univariate analyses, several abnormalities in laryngeal anatomy and structural movement were significantly associated with aspiration, spillage, and residue. In a multivariable analysis, the only variables that remained significant with aspiration were pharyngeal weakness (Odds ratio = 2.57, 95%CI = 1.16-5.84, p = 0.019) and upper airway edema (Odds ratio = 3.24, 95%CI = 1.44-7.66, p = 0.004). These results demonstrated that dysphagia in ARF survivors is multifactorial and characterized by both anatomic and physiologic abnormalities. These findings may have important implications for the development of novel interventions to treat dysphagia in ARF survivors.Clinical Trials Registration ClinicalTrials.gov Identifier: NCT02363686, Aspiration in Acute Respiratory Failure Survivors.


Asunto(s)
Trastornos de Deglución , Insuficiencia Respiratoria , Deglución , Trastornos de Deglución/etiología , Humanos , Estudios Prospectivos , Aspiración Respiratoria/etiología , Insuficiencia Respiratoria/etiología , Sobrevivientes
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