Deep learning estimation of northern hemisphere soil freeze-thaw dynamics using satellite multi-frequency microwave brightness temperature observations.

Satellite microwave sensors are well suited for monitoring landscape freeze-thaw (FT) transitions owing to the strong brightness temperature (TB) or backscatter response to changes in liquid water abundance between predominantly frozen and thawed conditions. The FT retrieval is also a sensitive climate indicator with strong biophysical importance. However, retrieval algorithms can have difficulty distinguishing the FT status of soils from that of overlying features such as snow and vegetation, while variable land conditions can also degrade performance. Here, we applied a deep learning model using a multilayer convolutional neural network driven by AMSR2 and SMAP TB records, and trained on surface (~0-5 cm depth) soil temperature FT observations. Soil FT states were classified for the local morning (6 a.m.) and evening (6 p.m.) conditions corresponding to SMAP descending and ascending orbital overpasses, mapped to a 9 km polar grid spanning a five-year (2016-2020) record and Northern Hemisphere domain. Continuous variable estimates of the probability of frozen or thawed conditions were derived using a model cost function optimized against FT observational training data. Model results derived using combined multi-frequency (1.4, 18.7, 36.5 GHz) TBs produced the highest soil FT accuracy over other models derived using only single sensor or single frequency TB inputs. Moreover, SMAP L-band (1.4 GHz) TBs provided enhanced soil FT information and performance gain over model results derived using only AMSR2 TB inputs. The resulting soil FT classification showed favorable and consistent performance against soil FT observations from ERA5 reanalysis (mean percent accuracy, MPA: 92.7%) and in situ weather stations (MPA: 91.0%). The soil FT accuracy was generally consistent between morning and afternoon predictions and across different land covers and seasons. The model also showed better FT accuracy than ERA5 against regional weather station measurements (91.0% vs. 86.1% MPA). However, model confidence was lower in complex terrain where FT spatial heterogeneity was likely beneath the effective model grain size. Our results provide a high level of precision in mapping soil FT dynamics to improve understanding of complex seasonal transitions and their influence on ecological processes and climate feedbacks, with the potential to inform Earth system model predictions.

Modeling Terrestrial Dissolved Organic Carbon Loading to Western Arctic Rivers.

The mobilization and land-to-ocean transfer of dissolved organic carbon (DOC) in Arctic watersheds is intricately linked with the region's climate and water cycle, and furthermore at risk of changes from climate warming and associated impacts. This study quantifies model-simulated estimates of runoff, surface and active layer leachate DOC concentrations and loadings to western Arctic rivers, specifically for basins that drain into coastal waters between and including the Yukon and Mackenzie Rivers. Model validation leverages data from other field measurements, synthesis studies, and modeling efforts. The simulations effectively quantify DOC leaching in surface and subsurface runoff and broadly capture the seasonal cycle in DOC concentration and mass loadings reported from other studies that use river-based measurements. A marked east-west gradient in simulated spring and summer DOC concentrations of 24 drainage basins on the North Slope of Alaska is captured by the modeling, consistent with independent data derived from river sampling. Simulated loadings for the Mackenzie and Yukon show reasonable agreement with estimates of DOC export for annual totals and four of the six seasonal comparisons. Nearly equivalent loading occurs to rivers which drain north to the Beaufort Sea and west to the Bering and Chukchi Seas. The modeling framework provides a basis for understanding carbon export to coastal waters and for assessing impacts of hydrological cycle intensification and permafrost thaw with ongoing warming in the Arctic.

The UK's Life Sciences Strategy: opportunities for clinical pharmacology.

The UK's Life Sciences Strategy provides UK clinical pharmacologists with a unique opportunity to enhance the impact of their discipline on patients and the NHS as well as the pharmaceutical industry. The full benefits of electronic prescribing systems, supported by artificial intelligence, will require clinical pharmacological expertise. Similarly, the Strategy's support for 'healthy ageing' will only be realized if clinical pharmacologists are able to use their expertise in promoting the safe and effective use of medicines in older people. Furthermore, their needs to be an active - and continuing - collaboration between clinical pharmacologists in the NHS and the pharmaceutical industry in general as well as with the discipline of pharmaceutical medicine.

Improving public health by improving clinical trial guidelines and their application.

Evidence generated from randomized controlled trials forms the foundation of cardiovascular therapeutics and has led to the adoption of numerous drugs and devices that prolong survival and reduce morbidity, as well as the avoidance of interventions that have been shown to be ineffective or even unsafe. Many aspects of cardiovascular research have evolved considerably since the first randomized trials in cardiology were conducted. In order to be large enough to provide reliable evidence about effects on major outcomes, cardiovascular trials may now involve thousands of patients recruited from hundreds of clinical sites in many different countries. Costly infrastructure has developed to meet the increasingly complex organizational and operational requirements of these clinical trials. Concerns have been raised that this approach is unsustainable, inhibiting the reliable evaluation of new and existing treatments, to the detriment of patient care. These issues were considered by patients, regulators, funders, and trialists at a meeting of the European Society of Cardiology Cardiovascular Roundtable in October 2015. This paper summarizes the key insights and discussions from the workshop, highlights subsequent progress, and identifies next steps to produce meaningful change in the conduct of cardiovascular clinical research.

Incidence of adult Huntington's disease in the UK: a UK-based primary care study and a systematic review.

OBJECTIVES: The prevalence of Huntington's disease (HD) recorded in the UK primary care records has increased twofold between 1990 and 2010. This investigation was undertaken to assess whether this might be due to an increased incidence. We have also undertaken a systematic review of published estimates of the incidence of HD. SETTING: Incident patients with a new diagnosis of HD were identified from the primary care records of the Clinical Practice Research Datalink (CPRD). The systematic review included all published estimates of the incidence of HD in defined populations. PARTICIPANTS: A total of 393 incident cases of HD were identified from the CPRD database between 1990 and 2010 from a total population of 9,282,126 persons. PRIMARY AND SECONDARY OUTCOME MEASURES: The incidence of HD per million person-years was estimated. From the systematic review, the extent of heterogeneity of published estimates of the incidence of HD was examined using the I(2) statistic. RESULTS: The data showed that the incidence of HD has remained constant between 1990 and 2010 with an overall rate of 7.2 (95% CI 6.5 to 7.9) per million person-years. The systematic review identified 14 independent estimates of incidence with substantial heterogeneity and consistently lower rates reported in studies from East Asia compared with those from Australia, North America and some--though not all--those from Europe. Differences in incidence estimates did not appear to be explained solely by differences in case ascertainment or diagnostic methods. CONCLUSIONS: The rise in the prevalence of diagnosed HD in the UK, between 1990 and 2010, cannot be attributed to an increase in incidence. Globally, estimates of the incidence of HD show evidence of substantial heterogeneity with consistently lower rates in East Asia and parts of Europe. Modifiers may play an important role in determining the vulnerability of different populations to expansions of the HD allele.

The Prevalence of Huntington's Disease.

BACKGROUND: Reviews of the epidemiology of Huntington's disease (HD) suggest that its worldwide prevalence varies widely. This review was undertaken to confirm these observations, to assess the extent to which differences in case-ascertainment and/or diagnosis might be responsible, and to investigate whether the prevalence pattern has changed over the past 50 years. METHODS: Eighty two relevant studies were identified from Medline and Embase, previous reviews, scrutiny of references from included and excluded studies and enquiry among those interested in the field. RESULTS: The lowest rates were among the Asians and the highest among the Caucasians. The differences are not fully explained by varying approaches to case-ascertainment or diagnosis. There was evidence of an increasing prevalence of between 15 and 20% per decade in studies from Australia, North America and Western Europe. CONCLUSIONS: The prevalence of HD varies more than tenfold between different geographical regions. This variation can in part be attributed to differences in case-ascertainment and/or diagnostic criteria, but there is consistent evidence of a lower incidence in Asian populations. There is also evidence that in Australia, North America and in Western Europe (including the United Kingdom), prevalence has increased over the past 50 plus years.

National Institute for Clinical Excellence: NICE works.

The National Institute for Clinical Excellence was established in 1999. Its original remit was to undertake technology appraisals of (mainly) new interventions and to develop clinical guidelines. In providing both forms of guidance, it was required to take into account both clinical and cost effectiveness. After a difficult first few months, it gained the confidence and trust of the professions. It subsequently gained additional responsibilities with a commensurate increase in its staffing and budget. It is, moreover, the only one of the National Health Service organisations established in the late 1990s and early 2000s to have not only survived but grown. This paper describes not only the National Institute for Clinical Excellence's early years but also, in the author's view, the features of its guidance programmes that led to its success and (in retrospect) some things it could have done differently.

Evidence, values, and decision making.

BACKGROUND: The evidence supporting the use of new, or established, interventions may be derived from either (or both) experimental or observational study designs. Although a rigorous examination of the evidence base for clinical and cost-effectiveness is essential, it is never sufficient, and those undertaking a health technology assessment (HTA) also have to exercise judgments. METHODS: The basis for this discussion is largely from the author's experience as chairman of the national Institute for Health and Clinical Excellence (NICE). RESULTS: The judgments necessary for HTA to make are twofold. Scientific judgments relate to the interpretation of the science. Social value judgments are concerned with the ethical principles, preferences, culture, and aspirations of society. CONCLUSIONS: How scientific and social value judgments might be most appropriately captured is a challenge for all HTA agencies. Although competent HTA bodies should be able to exercise scientific judgments they have no legitimacy to impose their own social values. These must ultimately be informed by the general public.

Clinical pharmacologists in pharmacoeconomics: what is their role?

Clinical pharmacologists have three distinct contributions to make in the economic evaluation of new and existing pharmaceutical products: they should play a significant role in promoting the principles of "opportunity costs" in healthcare; they need to have a broad understanding of the methodology of economic evaluation in healthcare; they have a critical role in bringing their specialist knowledge, skills and experience in decision-making. In fulfilling these essential roles clinical pharmacologists may find themselves outside their conventional "comfort zones". Nevertheless, clinical pharmacologists need to rise to the occasion if they are to meet their obligations to patients and to society as a whole.