Losartan improves exercise tolerance in patients with diastolic dysfunction and a hypertensive response to exercise

AbstractOBJECTIVESThe aim of the study was to test the hypothesis that angiotensin II (Ang II) blockade would improve exercise tolerance in patients with diastolic dysfunction and a marked increase in systolic blood pressure (SBP) during exercise.BACKGROUNDDiastolic dysfunction may be exacerbated during exercise, especially if there is a marked increase in SBP. Angiotensin II may contribute to the hypertensive response to exercise and impair diastolic performance.METHODSWe performed a randomized, double-blind, placebo-controlled, crossover study of two weeks of losartan (50 mg q.d.) on exercise tolerance and quality of life. The subjects were 20 patients, mean age 64 ± 10 years with normal left ventricular systolic function (EF >50%), no ischemia on stress echocardiogram, mitral flow velocity E/A <1, normal resting SBP (<150 mm Hg), and a hypertensive response to exercise (SBP >200 mm Hg). Exercise echocardiograms (Modified Bruce Protocol) and the Minnesota Living With Heart Failure questionnaire were administered at baseline, and after each two-week treatment period, separated by a two-week washout period.RESULTSResting blood pressure (BP) was unaltered by placebo or losartan. During control, patients were able to exercise for 11.3 ± 2.5 (mean ± SD) min, with a peak exercise SBP of 226 ± 24 mm Hg. After two weeks of losartan, baseline BP was unaltered, but peak SBP during exercise decreased to 193 ± 27 mm Hg (p < 0.05 vs. baseline and placebo), and exercise time increased to 12.3 ± 2.6 min (p < 0.05 vs. baseline and placebo). With placebo, there was no improvement in exercise duration (11.0 ± 2.0 min) or peak exercise SBP (217 ± 26 mm Hg). Quality of life improved with losartan (18 ± 22, p < 0.05) compared to placebo (22 ± 26).CONCLUSIONSIn patients with Doppler evidence of diastolic dysfunction at rest and a hypertensive response to exercise, Ang II receptor blockade blunts the hypertensive response to exercise, increases exercise tolerance and improves quality of life

Sustainable intensification of aquaculture value chains between Asia and Europe: A framework for understanding impacts and challenges

Sustainable intensification (SI) is defined and interpreted in terms of a framework to support production of farmed aquatic animals in Asia and their trade with Europe. A novel holistic perspective to value chain analysis, informed by a range of sustainability tools, is used to explain the dynamic in the trade that is having significant impacts on livelihoods in both regions. The origins of SI in agriculture are first described and their congruence with aquaculture clarified. Asian aquaculture systems, based on their emergent properties, are then located within a SI framework considering possible boundaries (enterprise, zone or whole value chain). The implications of conventional intensification, and alternatives are explored with reference to specific examples and impacts on the local and global environment, human and aquatic animal health and welfare. The challenges to sustainability of such value chains and implications for their governance, food culture and consumer habits are considered. Local consumption of seafood in Asia is found to be a major driver of growth and alternative markets for exports regionally and in Low and Medium income countries (LMIC) are likely to impact on employment and power in the value chain between Europe and Asia. The benefits of viewing farmed seafood as part of broader food landscapes are identified in the analysis, as is a shift in the focus from volume to value in terms of goal setting. More holistic perspectives of sustainability also emerge as necessary to describe and interpret global value chains rather than limited reductionist, production- orientated views. A diversity of trends in the development of farmed seafood is identified in contrast to any simplistic move to intensification, likely informed by economic, environmental and social factors in producer and consumer countries.  Statement of relevance  Global imbalances in production and consumption of farmed seafood are stimulating trade between Asia and Europe. The dynamic of global value chains around this emergent trade and their alignment with broader sustainability criteria, as applied to sustainable intensification of food production, are highly relevant to global food security

Phase transition curves for mesoscopic superconducting samples

We compute the phase transition curves for mesoscopic superconductors. Special emphasis is given to the limiting shape of the curve when the magnetic flux is large. We derive an asymptotic formula for the ground state of the Schr\"odinger equation in the presence of large applied flux. The expansion is shown to be sensitive to the smoothness of the domain. The theoretical results are compared to recent experiments.Comment: 8 pages, 1 figur

Detecting Stress in Glasshouse Plants Using Color Infrared Imagery: A Potential New Application for Remote Sensing

English: Studies were conducted to evaluate the effectiveness of color infrared (CIR) film for detecting physiological stress in plants located within glasshouse structures. Spectroradiometer measurements obtained within and outside of a structure constructed of polycarbonate plastic indicated no significant attenuation or disruption of visible and near-infrared radiation entering the structure. CIR photographs of cucumber seedlings (Cucumis sativus) obtained within the greenhouse were comparable in quality to those obtained outside the structure, and clearly distinguished between foliage of healthy plants and those subjected to a moderate level of nitrogen stress. In CIR imagery of a trifoliate orange tree (Poncirus trifoliata (L.) Raf.) obtained within a greenhouse constructed of yellow fiberglass panels, leaves damaged by citrus red mites (Panonychus citri [McGregor]) were distinguishable from healthy foliage, and the distribution of damaged leaves on the tree itself was clearly evident. These results suggest that remote sensing techniques which have been used successfully to monitor conventional field crops are readily extendable to the commercial glasshouse environment with certain modifications. Spanish: Se condujeron estudios para evaluar la eficacia de la película infrarroja de color (CIR) para detectar el estrés fisiológico en las plantas situadas dentro de un invernadero. Las mediciones del spectroradiómetro obtenidas dentro y fuera de un invernadero construido con plástico de policarbonato no indicaron ninguna atenuación o interrupción significativa de la radiación visible y del cercano infrarrojo que penetraba al invernadero. Las fotografías con CIR de las plantas de semillero de pepino (Cucumis sativus) obtenidas dentro del invernadero fueron comparables en calidad a aquellas obtenidas fuera de este, y distinguieron claramente entre el follaje de plantas sanas y de aquellas sometidas a un nivel moderado de estrés de nitrógeno. En imágenes de CIR de un naranjo trifoliado (Poncirus trifoliata (L.) Raf.) obtenidas dentro de un invernadero construido de paneles amarillos de fibra de vidrio, las hojas dañadas por el ácaro rojo de los cítricos (Panonychus citri [McGregor]) se distinguieron del follaje sano, y la distribución de hojas dañadas en el árbol mismo fueron claramente evidentes. Estos resultados sugieren que las técnicas de detección a distancia que se han utilizado con éxito para supervisar campos de cultivo convencionales, también pueden usarse fácilmente, con algunas modificaciones, en cultivos comerciales en invernadero

An internet-based intervention with brief nurse support to manage obesity in primary care (POWeR+): a pragmatic, parallel-group, randomised controlled trial

Background The obesity epidemic has major public health consequences. Expert dietetic and behavioural counselling with intensive follow-up is effective, but resource requirements severely restrict widespread implementation in primary care, where most patients are managed. We aimed to estimate the effectiveness and cost-effectiveness of an internet-based behavioural intervention (POWeR+) combined with brief practice nurse support in primary care. Methods We did this pragmatic, parallel-group, randomised controlled trial at 56 primary care practices in central and south England. Eligible adults aged 18 years or older with a BMI of 30 kg/m2 or more (or ≥28 kg/m2 with hypertension, hypercholesterolaemia, or diabetes) registered online with POWeR+—a 24 session, web-based, weight management intervention lasting 6 months. After registration, the website automatically randomly assigned patients (1:1:1), via computer-generated random numbers, to receive evidence-based dietetic advice to swap foods for similar, but healthier, choices and increase fruit and vegetable intake, in addition to 6 monthly nurse follow-up (control group); web-based intervention and face-to-face nurse support (POWeR+Face-to-face [POWeR+F]; up to seven nurse contacts over 6 months); or web-based intervention and remote nurse support (POWeR+Remote [POWeR+R]; up to five emails or brief phone calls over 6 months). Participants and investigators were masked to group allocation at the point of randomisation; masking of participants was not possible after randomisation. The primary outcome was weight loss averaged over 12 months. We did a secondary analysis of weight to measure maintenance of 5% weight loss at months 6 and 12. We modelled the cost-effectiveness of each intervention. We did analysis by intention to treat, with multiple imputation for missing data. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN21244703. Findings Between Jan 30, 2013, and March 20, 2014, 818 participants were randomly assigned to the control group (n=279), the POWeR+F group (n=269), or the POWeR+R group (n=270). Weight loss averaged over 12 months was recorded in 666 (81%) participants. The control group lost almost 3 kg over 12 months (crude mean weight: baseline 104·38 kg [SD 21·11; n=279], 6 months 101·91 kg [19·35; n=136], 12 months 101·74 kg [19·57; n=227]). The primary imputed analysis showed that compared with the control group, patients in the POWeR+F group achieved an additional weight reduction of 1·5 kg (95% CI 0·6–2·4; p=0·001) averaged over 12 months, and patients in the POWeR+R group achieved an additional 1·3 kg (0·34–2·2; p=0·007). 21% of patients in the control group had maintained a clinically important 5% weight reduction at month 12, compared with 29% of patients in the POWeR+F group (risk ratio 1·56, 0·96–2·51; p=0·070) and 32% of patients in the POWeR+R group (1·82, 1·31–2·74; p=0·004). The incremental overall cost to the health service per kg weight lost with the POWeR+ interventions versus the control strategy was £18 (95% CI −129 to 195) for POWeR+F and –£25 (−268 to 157) for POWeR+R; the probability of being cost-effective at a threshold of £100 per kg lost was 88% and 98%, respectively. No adverse events were reported. Interpretation Weight loss can be maintained in some individuals by use of novel written material with occasional brief nurse follow-up. However, more people can maintain clinically important weight reductions with a web-based behavioural program and brief remote follow-up, with no increase in health service costs. Future research should assess the extent to which clinically important weight loss can be maintained beyond 1 year

An orthogonal C-H borylation - cross-coupling strategy for the preparation of tetrasubstituted "A(2)B(2)''-chrysene derivatives with tuneable photophysical properties

Cl-substituents serve as a functionalisable regiocontrol element for the orthogonal functionalisation of chrysene.</p

Influence of the confinement geometry on surface superconductivity

The nucleation field for surface superconductivity, $H_{c3}$, depends on the geometrical shape of the mesoscopic superconducting sample and is substantially enhanced with decreasing sample size. As an example we studied circular, square, triangular and wedge shaped disks. For the wedge the nucleation field diverges as $H_{c3}/H_{c2}=\sqrt{3}/\alpha$ with decreasing angle ($\alpha$) of the wedge, where $H_{c2}$ is the bulk upper critical field.Comment: 4 pages, 3 figures. Accepted for publication in Phys. Rev.

Techniques to Facilitate the Acquisition of Accurate Spectral Measurements and Multispectral Imagery of Plant Foliage Under Artificial Lighting Conditions

Spectral measurements obtained in the laboratory under artificial lighting sources have been used for many years to develop spectral ‘libraries’ for various soil types, rocks and minerals, and other inanimate features occurring on or near the earth’s surface. Quartz halogen lamps have been shown to emit all of the electromagnetic (EMR) wavelengths required for the acquisition of quality multispectral imagery, and various techniques have been developed to facilitate the acquisition of accurate spectral measurements using such artificial lighting sources. Our objectives in this study were to evaluate the several factors of critical importance in obtaining accurate spectral measurements for plant foliage in the laboratory, including the effects of leaf orientation, excision, and background reflectance on reflectance of visible and NIR wavelengths. Results demonstrated that accurate spectral measurements and imagery of various types of foliage may be obtained using quartz halogen lighting provided that excised leaf samples are placed on an NIR-absorbent background and samples are maintained in containers designed to minimize desiccation

Juneau, Alaska’s Successful Response to COVID-19: A Case Study of Adaptive Leadership in a Complex System

Juneau, Alaska, kept COVID-19 deaths lower than in other similar jurisdictions. We argue that adaptive leadership—the early decisions and actions of Juneau’s leaders, effective communications, and emergent new collaborative structures—in the context of municipal ownership of key assets enabled Juneau’s success. The result of 61 interviews and follow-up research, this case study contributes a better understanding of which institutional design, communication, and collaborative factors mattered in responding to the pandemic. Adaptive leadership provides a better explanation for Juneau’s success than alternatives that focus on its isolation, home-rule status, and socio-economic structure.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This article was funded by the National Science Foundation ( 2028928).Ye