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1.
Nature ; 620(7976): 1018-1024, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37612503

RESUMEN

Coral reefs are highly diverse ecosystems that thrive in nutrient-poor waters, a phenomenon frequently referred to as the Darwin paradox1. The energy demand of coral animal hosts can often be fully met by the excess production of carbon-rich photosynthates by their algal symbionts2,3. However, the understanding of mechanisms that enable corals to acquire the vital nutrients nitrogen and phosphorus from their symbionts is incomplete4-9. Here we show, through a series of long-term experiments, that the uptake of dissolved inorganic nitrogen and phosphorus by the symbionts alone is sufficient to sustain rapid coral growth. Next, considering the nitrogen and phosphorus budgets of host and symbionts, we identify that these nutrients are gathered through symbiont 'farming' and are translocated to the host by digestion of excess symbiont cells. Finally, we use a large-scale natural experiment in which seabirds fertilize some reefs but not others, to show that the efficient utilization of dissolved inorganic nutrients by symbiotic corals established in our laboratory experiments has the potential to enhance coral growth in the wild at the ecosystem level. Feeding on symbionts enables coral animals to tap into an important nutrient pool and helps to explain the evolutionary and ecological success of symbiotic corals in nutrient-limited waters.


Asunto(s)
Antozoos , Ecosistema , Nitrógeno , Fósforo , Fotosíntesis , Simbiosis , Animales , Antozoos/crecimiento & desarrollo , Antozoos/metabolismo , Antozoos/fisiología , Nitrógeno/metabolismo , Fósforo/metabolismo , Simbiosis/fisiología , Aves/fisiología
2.
J Am Chem Soc ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953610

RESUMEN

The development of intrinsically recyclable cross-linked materials remains challenged by the inherently unfavorable chemical equilibrium that dictates the efficiency of the reversible covalent bonding/debonding chemistry. Rather than having to (externally) manipulate the bonding equilibrium, we here introduce a new reversible chemistry platform based on monosubstituted thiomaleimides that can undergo complete and independent light-activated covalent bonding and on-demand thermal debonding above 120 °C. Specifically, repeated bonding/debonding of a small-molecule thiomaleimide [2 + 2] photodimer is demonstrated over five heat/light cycles with full conversion in both directions, thereby regenerating its initial monothiomaleimide constituents. This motivated the synthesis of multifunctional thiomaleimide reagents as precursors for the design of covalently cross-linked networks that display intrinsic switching between a monomeric and polymeric state. The resulting materials are shown to covalently dissociate and depolymerize upon heating both in solution and in bulk, thus transforming the densely photo-cross-linked material back into a viscous liquid. Temperature-regulated photorheology evidenced the intrinsic recyclability of the thiomaleimide-based thermosets during multiple cycles of UV cross-linking and thermal de-cross-linking. The thermally reversible photodimerization of thiomaleimides presents a new addition to the designer playground of dynamic polymer networks, providing interesting opportunities for the reprocessing and closed-loop recycling of covalently cross-linked materials.

3.
Bioconjug Chem ; 35(3): 400-411, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38366969

RESUMEN

Photodynamic therapy (PDT) is a cancer treatment strategy that utilizes photosensitizers to convert oxygen within tumors into reactive singlet oxygen (1O2) to lyse tumor cells. Nevertheless, pre-existing tumor hypoxia and oxygen consumption during PDT can lead to an insufficient oxygen supply, potentially reducing the photodynamic efficacy. In response to this issue, we have devised a pH-responsive amphiphilic triblock fluorinated polymer (PDP) using copper-mediated RDRP. This polymer, composed of poly(ethylene glycol) methyl ether acrylate, 2-(diethylamino)ethyl methacrylate, and (perfluorooctyl)ethyl acrylate, self-assembles in an aqueous environment. Oxygen, chlorine e6 (Ce6), and doxorubicin (DOX) can be codelivered efficiently by PDP. The incorporation of perfluorocarbon into the formulation enhances the oxygen-carrying capacity of PDP, consequently extending the lifetime of 1O2. This increased lifetime, in turn, amplifies the PDT effect and escalates the cellular cytotoxicity. Compared with PDT alone, PDP@Ce6-DOX-O2 NPs demonstrated significant inhibition of tumor growth. This study proposes a novel strategy for enhancing the efficacy of PDT.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Porfirinas , Humanos , Polímeros de Fluorocarbono , Oxígeno , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Hipoxia/tratamiento farmacológico , Concentración de Iones de Hidrógeno
4.
Br J Clin Pharmacol ; 90(7): 1699-1710, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38616172

RESUMEN

AIMS: Genetic testing can be used to improve the safety and effectiveness of commonly prescribed medicines-a concept known as pharmacogenetics. This study aimed to quantify members of the UK public's preferences for a pharmacogenetic service to be delivered in primary care in the National Health Service. METHODS: Members of the UK population were surveyed via an online panel company. Respondents completed 1 of 2 survey versions, asking respondents to select their preferred pharmacogenetic testing service in the context of a presentation of low mood or pain. A conditional logit model was estimated, before the best functional form for the dataset was identified. Preference heterogeneity was identified via latent class analysis. Coefficients from the final selected models were used to estimate uptake in the context of different hypothetical pharmacogenetic services. RESULTS: Responses from 1993 individuals were included in the analysis. There were no differences observed in preference between the 2 clinical scenarios. Conditional logit analysis, using maximum likelihood estimation, indicated that respondents preferred to have noninvasive tests and wanted their data to be shared between different healthcare organizations to guide future prescribing. There was a preference for regional over national data sharing initiatives, and respondents preferred to have access to their data. Predicted uptake varied considerably, ranging from 51% to >99%, depending on design of the service. CONCLUSION: This study identifies public preferences for a pharmacogenetic testing service and demonstrates how predicted uptake can be impacted by relatively minor adaptations. This highlights areas for prioritization during development of future pharmacogenetic services.


Asunto(s)
Pruebas de Farmacogenómica , Medicina Estatal , Humanos , Pruebas de Farmacogenómica/métodos , Masculino , Femenino , Reino Unido , Adulto , Persona de Mediana Edad , Anciano , Encuestas y Cuestionarios , Adulto Joven , Prioridad del Paciente , Adolescente , Conducta de Elección , Farmacogenética , Atención Primaria de Salud
5.
Macromol Rapid Commun ; 45(8): e2300692, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38288674

RESUMEN

Measurement of molecular weight is an integral part of macromolecular and polymer characterization which usually has limitations. Herein, this article presents the use of a bench-top 80 MHz Nuclear Magnetic Resonance (NMR) spectrometer for diffusion-ordered spectroscopy as a practical and rapid approach for the determination of molecular weight/size using a novel solvent and polymer-independent universal calibration.


Asunto(s)
Sustancias Macromoleculares , Espectroscopía de Resonancia Magnética , Peso Molecular , Polímeros , Polímeros/química , Espectroscopía de Resonancia Magnética/métodos , Sustancias Macromoleculares/química , Difusión
7.
J Adv Nurs ; 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38186205

RESUMEN

AIM: To explore the views of neonatal intensive care nursing staff on the deliverability of a novel genetic point-of-care test detecting a genetic variant associated with antibiotic-induced ototoxicity. DESIGN: An interpretive, descriptive, qualitative interview study. METHODS: Data were collected using semi-structured interviews undertaken between January and November 2020. Participants were neonatal intensive care nursing staff taking part in the Pharmacogenetics to Avoid Loss of Hearing trial. RESULTS: Thematic analysis resulted in four themes: perceived clinical utility; the golden hour; point-of-care device; training and support. Recommendations were made to streamline the protocol and ongoing training and support were considered key to incorporating the test into routine care. CONCLUSION: Exploring the views of nurses involved in the delivery of the point-of-care test was essential in its implementation. By the study endpoint, all participants could see the value of routine clinical introduction of the point-of care test. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Nurses are in a key position to support the delivery of point-of-care genetic testing into mainstream settings. This study has implications for the successful integration of other genetic point-of-care tests in acute healthcare settings. IMPACT: The study will help to tailor the training and support required for routine deployment of the genetic point-of-care test. The study has relevance for nurses involved in the development and delivery of genetic point-of-care tests in other acute hospital settings. REPORTING METHOD: This qualitative study adheres to the Standards for Reporting Qualitative Research EQUATOR guidelines and utilizes COREQ and SRQR checklists. PATIENT OR PUBLIC CONTRIBUTION: All staff working on the participating neonatal intensive care units were trained to use the genetic point-of-care test. All inpatients on the participating units were eligible to have testing via the point-of-care test. The Pharmacogenetics to Avoid Loss of Hearing Patient and Public Involvement and Engagement group provided valuable feedback. TRIAL AND PROTOCOL REGISTRATION: Registered within the University of Manchester. Ethics approval reference numbers: IRAS: 253102 REC reference: 19/NW/0400. Also registered with the ISRCTN ref: ISRCTN13704894.

8.
Glob Chang Biol ; 29(15): 4279-4297, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37100767

RESUMEN

There are limited data for greenhouse gas (GHG) emissions from smallholder agricultural systems in tropical peatlands, with data for non-CO2 emissions from human-influenced tropical peatlands particularly scarce. The aim of this study was to quantify soil CH4 and N2 O fluxes from smallholder agricultural systems on tropical peatlands in Southeast Asia and assess their environmental controls. The study was carried out in four regions in Malaysia and Indonesia. CH4 and N2 O fluxes and environmental parameters were measured in cropland, oil palm plantation, tree plantation and forest. Annual CH4 emissions (in kg CH4 ha-1 year-1 ) were: 70.7 ± 29.5, 2.1 ± 1.2, 2.1 ± 0.6 and 6.2 ± 1.9 at the forest, tree plantation, oil palm and cropland land-use classes, respectively. Annual N2 O emissions (in kg N2 O ha-1 year-1 ) were: 6.5 ± 2.8, 3.2 ± 1.2, 21.9 ± 11.4 and 33.6 ± 7.3 in the same order as above, respectively. Annual CH4 emissions were strongly determined by water table depth (WTD) and increased exponentially when annual WTD was above -25 cm. In contrast, annual N2 O emissions were strongly correlated with mean total dissolved nitrogen (TDN) in soil water, following a sigmoidal relationship, up to an apparent threshold of 10 mg N L-1 beyond which TDN seemingly ceased to be limiting for N2 O production. The new emissions data for CH4 and N2 O presented here should help to develop more robust country level 'emission factors' for the quantification of national GHG inventory reporting. The impact of TDN on N2 O emissions suggests that soil nutrient status strongly impacts emissions, and therefore, policies which reduce N-fertilisation inputs might contribute to emissions mitigation from agricultural peat landscapes. However, the most important policy intervention for reducing emissions is one that reduces the conversion of peat swamp forest to agriculture on peatlands in the first place.


Asunto(s)
Dióxido de Carbono , Gases de Efecto Invernadero , Humanos , Dióxido de Carbono/análisis , Metano/análisis , Agricultura , Suelo , Gases de Efecto Invernadero/análisis , Árboles , Indonesia , Nitrógeno , Óxido Nitroso/análisis
9.
Diabet Med ; 40(11): e15209, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37634235

RESUMEN

AIMS: The NHS Diabetes Prevention Programme (NHS DPP) is a large-scale, England-wide behaviour change programme for people at high risk of progressing to type 2 diabetes. We summarise the findings of our six-year DIPLOMA evaluation of its implementation and impact and highlight insights for future programmes. METHODS: Using qualitative interviews, document analysis, observation, surveys and large dataset analysis, eight interlinked work packages considered: equity of access; implementation; service delivery and fidelity; programme outcomes; comparative effectiveness and cost-effectiveness in reducing diabetes incidence; and patient decision making and experience. RESULTS: Delivery of the NHS DPP encountered barriers across many aspects of the programme, and we identified inequalities in terms of the areas, organisations and patient populations most likely to engage with the programme. There was some loss of fidelity at all stages from commissioning to participant understanding. Despite these challenges, there was evidence of significant reductions in diabetes incidence at individual and population levels. The programme was cost-effective even within a short time period. CONCLUSIONS: Despite the challenge of translating research evidence into routine NHS delivery at scale, our findings suggest that an individual-level approach to the prevention of type 2 diabetes in a 'high-risk' population was more effective than usual care. By embedding evaluation with programme delivery and working closely with the NHS DPP team, we provided actionable insights for improving communications with potential participants, supporting primary care referral, honing the delivery model with better provider relationships and more patient choice, increasing understanding of behaviour change techniques, and enriching the educational and health coaching content.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/prevención & control , Medicina Estatal , Inglaterra/epidemiología , Factores de Riesgo , Terapia Conductista/métodos
10.
Soft Matter ; 19(20): 3711-3722, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37190902

RESUMEN

Understanding the behaviour of human blood outside of the body has important implications in forensic research, especially related to bloodstain pattern analysis (BPA). The design of forensic blood substitutes (FBSs) can provide many advantages, including the incorporation of multiple physiological components for use as safe and reliable materials for forensic applications. In this work, we present the design of synthetic alginate and xanthan gum-based hydrogels that contain electrosprayed microparticles (MPs) with and without crosslinked DNA. In addition to the MPs, the alginate/xanthan gum FBS materials include fillers to alter the physical appearance and fluid properties of the material. The optimized FBS consisted of alginate (1% w/v) and xanthan gum (5.0 × 10-3% w/v), 2 mM CaCl2, ferric citrate (0.5% w/v), magnesium silicate (0.25% w/v), Allura Red dye (2% w/v), 0.025% v/v Tween 20 and 9.5% v/v MPs. The FBS was tested in passive dripping experiments relevant to BPA scenarios at various impact angles. The spreading ratio (Ds/D0) was determined for 90° stains made on a paper surface and compared to bovine blood where the FBS was shown to simulate accurate and predictable spreading behaviour. In addition, we simulated other common BPA scenarios (e.g., impact patterns) and evidence processing potential. The FBS could be swabbed, and the DNA could be extracted, amplified, and genotyped analogous to human blood evidence. A stability test was also conducted which revealed a shelf-life of over 4 weeks where the material remains relevant to human blood at physiological temperature.


Asunto(s)
Manchas de Sangre , Sustitutos Sanguíneos , Animales , Bovinos , Humanos , Hidrogeles , Alginatos , Polisacáridos Bacterianos
11.
BMC Health Serv Res ; 23(1): 1043, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37773125

RESUMEN

BACKGROUND: The National Health Service Diabetes Prevention Programme (NHS DPP) was commissioned by NHS England in 2016 and rolled out in three 'waves' across the whole of England. It aims to help people with raised blood glucose levels reduce their risk of developing type 2 diabetes through behaviour change techniques (e.g., weight loss, dietary changes and exercise). An independent, longitudinal, mixed methods evaluation of the NHS DPP was undertaken. We report the findings from the implementation work package: a qualitative interview study with designated local leads, responsible for the local commissioning and implementation of the programme. The aim of the study was to explore how local implementation processes were enacted and adapted over time. METHODS: We conducted a telephone interview study across two time-points. Twenty-four semi-structured interviews with local leads across 19 sampled case sites were undertaken between October 2019 and January 2020 and 13 interviews with local leads across 13 sampled case sites were conducted between July 2020 and August 2020. Interviews aimed to reflect on the experience of implementation and explore how things changed over time. RESULTS: We identified four overarching themes to show how implementation was locally enacted and adapted across the sampled case sites: 1. Adapting to provider change; 2. Identification and referral; 3. Enhancing uptake in underserved populations; and 4. Digital and remote service options. CONCLUSION: This paper reports how designated local leads, responsible for local implementation of the NHS DPP, adapted implementation efforts over the course of a changing national diabetes prevention programme, including how local leads adapted implementation during the COVID-19 pandemic. This paper highlights three main factors that influence implementation: the importance of facilitation, the ability (or not) to tailor interventions to local needs and the role of context in implementation.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/prevención & control , Medicina Estatal , Pandemias , COVID-19/epidemiología , COVID-19/prevención & control , Investigación Cualitativa
12.
Proc Natl Acad Sci U S A ; 117(49): 30980-30987, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33229561

RESUMEN

Sea-level rise resulting from the instability of polar continental ice sheets represents a major socioeconomic hazard arising from anthropogenic warming, but the response of the largest component of Earth's cryosphere, the East Antarctic Ice Sheet (EAIS), to global warming is poorly understood. Here we present a detailed record of North Atlantic deep-ocean temperature, global sea-level, and ice-volume change for ∼2.75 to 2.4 Ma ago, when atmospheric partial pressure of carbon dioxide (pCO2) ranged from present-day (>400 parts per million volume, ppmv) to preindustrial (<280 ppmv) values. Our data reveal clear glacial-interglacial cycles in global ice volume and sea level largely driven by the growth and decay of ice sheets in the Northern Hemisphere. Yet, sea-level values during Marine Isotope Stage (MIS) 101 (∼2.55 Ma) also signal substantial melting of the EAIS, and peak sea levels during MIS G7 (∼2.75 Ma) and, perhaps, MIS G1 (∼2.63 Ma) are also suggestive of EAIS instability. During the succeeding glacial-interglacial cycles (MIS 100 to 95), sea levels were distinctly lower than before, strongly suggesting a link between greater stability of the EAIS and increased land-ice volumes in the Northern Hemisphere. We propose that lower sea levels driven by ice-sheet growth in the Northern Hemisphere decreased EAIS susceptibility to ocean melting. Our findings have implications for future EAIS vulnerability to a rapidly warming world.

13.
J Adv Nurs ; 79(7): 2568-2584, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36811300

RESUMEN

AIMS: To explore barriers to, and facilitators of, adherence to compression therapy, from the perspective of people with venous leg ulcers. DESIGN: An interpretive, qualitative, descriptive study involving interviews with patients. METHODS: Participants were purposively sampled from respondents to a survey exploring attitudes to compression therapy in people with venous leg ulcers. Sampling continued until data saturation: 25 interviews between December 2019 and July 2020. Inductive thematic analysis of interview transcripts was undertaken to create a framework for the data, followed by deductive analysis informed by the Common-Sense Model of Self-Regulation. RESULTS: A range of knowledge and understanding about the cause of venous leg ulcers and the mechanisms of compression therapy was demonstrated, which was not particularly related to adherence. Participants talked about their experience with different compression methods and their concerns about the length of time healing could take. They also spoke about aspects of the organization of services which affected their care. CONCLUSION: Identifying specific, individual barriers/facilitators to compression therapy is not simple, rather factors combine to make adherence more or less likely or possible. There was no clear relationship between an understanding of the cause of VLUs or the mechanism of compression therapy and adherence; different compression therapies presented different challenges for patients; unintentional non-adherence was frequently mentioned; and the organization of services could impact on adherence. Ways in which people could be supported to adhere to compression therapy are indicated. Implications for practice include issues relating to communication with patients; taking into account patients' lifestyles and ensuring that they know about useful 'aids'; providing services that are accessible and provide continuity of appropriately trained staff; minimizing unintentional non-adherence; and acknowledging that healthcare professionals will always need to support/advise those who cannot tolerate compression. IMPACT: Compression therapy is a cost-effective, evidence-based treatment for venous leg ulcers. However, there is evidence that patients do not always adhere to this therapy and there is limited research investigating reasons why patients do not wear compression. The study found no clear relationship between an understanding of the cause of VLUs or the mechanism of compression therapy and adherence; that different compression therapies presented different challenges for patients; that unintentional non-adherence was frequently mentioned and that the organization of services could impact on adherence. Attending to these findings offers the opportunity to increase the proportion of people undergoing appropriate compression therapy and achieving complete wound healing, the main outcome desired by this group. PATIENT/PUBLIC CONTRIBUTION: A patient representative sits on the Study Steering Group, contributing to the work from developing the study protocol and interview schedule to interpretation and discussion of findings. Members of a Wounds Research Patient and Public Involvement Forum were consulted about interview questions.


Asunto(s)
Úlcera de la Pierna , Úlcera Varicosa , Humanos , Úlcera Varicosa/terapia , Cicatrización de Heridas , Resultado del Tratamiento , Costos de la Atención en Salud , Investigación Cualitativa
14.
Br J Haematol ; 199(2): 277-284, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35922080

RESUMEN

We describe the management and the prevalence of iron deficiency anaemia (IDA) during pregnancy by comparison to standards. A cross-sectional national cohort study of women who had given birth six weeks prior to data collection was conducted at maternity units in the UK and Ireland. Participating centres collected data from 10 consecutive pregnant women. Analysis was descriptive to define the prevalence of IDA in pregnancy and the puerperium, and to compare the outcomes in women who had IDA with women who did not have anaemia anytime during pregnancy. Eighty-six maternity units contributed data on 860 pregnancies and births. The overall prevalence of IDA during pregnancy was 30.4% and in the puerperium 20%. Anaemic women were more likely to be from ethnic minorities, odds ratio 2.23 (1.50, 3.32). Adherence to national guidance was suboptimal, and the prevalence of anaemia in pregnancy remains very high. There is pressing need to explore barriers to early identification and effective management of iron deficiency. IDA should be considered a major public health problem in the UK.


Asunto(s)
Anemia Ferropénica , Anemia , Deficiencias de Hierro , Anemia Ferropénica/epidemiología , Anemia Ferropénica/terapia , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Embarazo , Prevalencia
15.
Thorax ; 77(9): 929-932, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35790388

RESUMEN

Despite good evidence of impaired innate antiviral responses in asthma, trials of inhaled interferon-ß given during exacerbations showed only modest benefits in moderate/severe asthma. Using human experimental rhinovirus infection, we observe robust in vivo induction of bronchial epithelial interferon response genes 4 days after virus inoculation in 25 subjects with asthma but not 11 control subjects. This signature correlated with virus loads and lower respiratory symptoms. Our data indicate that the in vivo innate antiviral response is dysregulated in asthma and open up the potential that prophylactic rather than therapeutic interferon therapy may have greater clinical benefit.


Asunto(s)
Asma , Inmunidad Innata , Interferones , Infecciones por Picornaviridae , Asma/inmunología , Asma/virología , Células Epiteliales/inmunología , Humanos , Interferones/inmunología , Infecciones por Picornaviridae/genética , Infecciones por Picornaviridae/inmunología , Rhinovirus
16.
Nature ; 529(7584): 59-62, 2016 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-26675732

RESUMEN

Thousands of transiting exoplanets have been discovered, but spectral analysis of their atmospheres has so far been dominated by a small number of exoplanets and data spanning relatively narrow wavelength ranges (such as 1.1-1.7 micrometres). Recent studies show that some hot-Jupiter exoplanets have much weaker water absorption features in their near-infrared spectra than predicted. The low amplitude of water signatures could be explained by very low water abundances, which may be a sign that water was depleted in the protoplanetary disk at the planet's formation location, but it is unclear whether this level of depletion can actually occur. Alternatively, these weak signals could be the result of obscuration by clouds or hazes, as found in some optical spectra. Here we report results from a comparative study of ten hot Jupiters covering the wavelength range 0.3-5 micrometres, which allows us to resolve both the optical scattering and infrared molecular absorption spectroscopically. Our results reveal a diverse group of hot Jupiters that exhibit a continuum from clear to cloudy atmospheres. We find that the difference between the planetary radius measured at optical and infrared wavelengths is an effective metric for distinguishing different atmosphere types. The difference correlates with the spectral strength of water, so that strong water absorption lines are seen in clear-atmosphere planets and the weakest features are associated with clouds and hazes. This result strongly suggests that primordial water depletion during formation is unlikely and that clouds and hazes are the cause of weaker spectral signatures.


Asunto(s)
Atmósfera/química , Medio Ambiente Extraterrestre/química , Planetas , Agua/análisis , Júpiter , Presión , Espectrofotometría Infrarroja , Telescopios , Temperatura
17.
Global Health ; 18(1): 62, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35715814

RESUMEN

"No regrets" buying - using Advance Purchase Agreements (APAs) - has characterized the response to recent pandemics such as Avian flu, Zika Virus, and now COVID-19. APAs are used to reduce demand uncertainty for product developers and manufacturers; to hedge against R&D and manufacturing risks; and to secure availability of products in the face of spiking demand. Evidence on the use of APAs to buy vaccines, medicines, diagnostics, and personal protective equipment during recent pandemics illustrates how these contracts can achieve their intended objectives for buyers. But, transferring risk from suppliers to buyers - as APAs do - can have consequences, including overbuying and overpaying. Furthermore, the widespread use of APAs by high-income countries has contributed to the striking inequities that have characterized the Swine flu and COVID-19 responses, delaying access to vaccines and other supplies for low- and middle-income countries (L&MICs).We identify seven ways to address some of the risks and disadvantages of APAs, including adoption of a global framework governing how countries enter into APAs and share any resulting supplies; voluntary pooling through joint or coordinated APAs; a concessional-capital-backed facility to allow international buyers and L&MICs to place options on products as an alternative to full purchase commitments; greater collection and sharing of market information to help buyers place smarter APAs; support for a resale market; building in mechanisms for donation from the outset; and transitioning away from APAs as markets mature. While a binding global framework could in theory prevent the competitive buying and hoarding that have characterized country/state responses to pandemics, it will be very challenging to put in place. The other solutions, while less sweeping, can nonetheless mitigate both the inequities associated with the current uncoordinated use of APAs and also some of the risks to individual buyers.Analysis of recent experiences can provide useful lessons on APAs for the next pandemic. It will be important to keep in mind, however, that these contractual instruments work by transferring risk to the buyer, and that buyers must therefore accept the consequences. In the spirit of "no regrets" purchasing, having bought what hindsight suggests was too much is generally preferable to having bought not enough.


Asunto(s)
COVID-19 , Gripe Humana , Vacunas , Infección por el Virus Zika , Virus Zika , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Gripe Humana/epidemiología , Pandemias/prevención & control , Equipo de Protección Personal
18.
Mol Ecol ; 30(23): 6121-6143, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34482596

RESUMEN

Pleistocene glacial cycles influenced the diversification of high-latitude wildlife species through recurrent periods of range contraction, isolation, divergence, and expansion from refugia and subsequent admixture of refugial populations. We investigate population size changes and the introgressive history of caribou (Rangifer tarandus) in western Canada using 33 whole genome sequences coupled with larger-scale mitochondrial data. We found that a major population expansion of caribou occurred starting around 110,000 years ago (kya), the start of the last glacial period. Additionally, we found effective population sizes of some caribou reaching ~700,000 to 1,000,000 individuals, one of the highest recorded historical effective population sizes for any mammal species thus far. Mitochondrial analyses dated introgression events prior to the LGM dating to 20-30 kya and even more ancient at 60 kya, coinciding with colder periods with extensive ice coverage, further demonstrating the importance of glacial cycles and events prior to the LGM in shaping demographic history. Reconstructing the origins and differential introgressive history has implications for predictions on species responses under climate change. Our results have implications for other whole genome analyses using pairwise sequentially Markovian coalescent (PSMC) analyses, as well as highlighting the need to investigate pre-LGM demographic patterns to fully reconstruct the origin of species diversity, especially for high-latitude species.


Asunto(s)
Reno , Animales , Cambio Climático , ADN Mitocondrial/genética , Variación Genética , Genoma , Humanos , Filogenia , Densidad de Población , Dinámica Poblacional , Reno/genética
19.
Health Econ ; 30(6): 1393-1416, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33786914

RESUMEN

Despite widespread use, evidence is sparse on whether financial incentives in healthcare should be linked to structure, process or outcome. We examine the impact of different incentive types on the quantity and effectiveness of referrals made by general practices to a new national prevention programme in England. We measured effectiveness by the number of referrals resulting in programme attendance. We surveyed local commissioners about their use of financial incentives and linked this information to numbers of programme referrals and attendances from 5170 general practices between April 2016 and March 2018. We used multivariate probit regressions to identify commissioner characteristics associated with the use of different incentive types and negative binomial regressions to estimate their effect on practice rates of referral and attendance. Financial incentives were offered by commissioners in the majority of areas (89%), with 38% using structure incentives, 69% using process incentives and 22% using outcome incentives. Compared to practices without financial incentives, neither structure nor process incentives were associated with statistically significant increases in referrals or attendances, but outcome incentives were associated with 84% more referrals and 93% more attendances. Outcome incentives were the only form of pay-for-performance to stimulate more participation in this national disease prevention programme.


Asunto(s)
Medicina General , Motivación , Humanos , Atención Primaria de Salud , Derivación y Consulta , Reembolso de Incentivo
20.
Health Res Policy Syst ; 19(1): 63, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33845858

RESUMEN

BACKGROUND: With innovation in service delivery increasingly viewed as crucial to the long-term sustainability of health systems, NHS England launched an ambitious new model of care (Vanguard) programme in 2015. Supported by a £350 million transformation fund, 50 Vanguard sites were to act as pilots for innovation in service delivery, to move quickly to change the way that services were delivered, breaking down barriers between sectors and improving the coordination and delivery of care. METHODS: As part of a national evaluation of the Vanguard programme, we conducted an evidence synthesis to assess the nature and quality of locally commissioned evaluations. With access to a secure, online hub used by the Vanguard and other integrated care initiatives, two researchers retrieved any documents from a locally commissioned evaluation for inclusion. All identified documents were downloaded and logged, and details of the evaluators, questions, methodological approaches and limitations in design and/or reporting were extracted. As included evaluations varied in nature and type, a narrative synthesis was undertaken. RESULTS: We identified a total of 115 separate reports relating to the locally commissioned evaluations. Five prominent issues relating to evaluation conduct were identified across included reports: use of logic models, number and type of evaluation questions posed, data sharing and information governance, methodological challenges and evaluation reporting in general. A combination of resource, data and time constraints means that evaluations often attempted to but did not fully address the wide range of questions posed by individual Vanguards. CONCLUSIONS: Significant investment was made in independent local evaluations of the Vanguard programme by NHS England. This synthesis represents the only comprehensive attempt to capture methodological learning and may serve as a key resource for researchers and policy-makers seeking to understand investigating large-scale system change, both within the NHS and internationally. PROSPERO (Registration number: CRD42017069282).


Asunto(s)
Programas de Gobierno , Medicina Estatal , Inglaterra , Humanos
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