Resonantly enhanced nonlinear optics in semiconductor quantum wells: An application to sensitive infrared detection

A novel class of coherent nonlinear optical phenomena, involving induced transparency in quantum wells, is considered in the context of a particular application to sensitive long-wavelength infrared detection. It is shown that the strongest decoherence mechanisms can be suppressed or mitigated, resulting in substantial enhancement of nonlinear optical effects in semiconductor quantum wells.Comment: 4 pages, 3 figures, replaced with revised versio

Coping with the effects of fear of failure in young elite athletes

Coping with stress is an important element in effective functioning at the elite level in sports, and fear of failure (FF) is an example of a stressor that athletes experience. Three issues underpin the present preliminary study. First, the prevalence of problems attributed to FF in achievement settings. Second, sport is a popular and significant achievement domain for children and adolescents. Third, there is a lack of research on FF in sport among this population. Therefore, the objectives of the study were to examine the effects of FF on young athletes and to find out their coping responses to the effects of FF. Interviews were conducted individually with nine young elite ath­letes (5 males, 4 females; ages 14-17 years). It was inferred from the data that FF affected the athletes' well-being, interpersonal behavior, sport performance, and schoolwork. The athletes employed a combination of problem-focused, emotion-fo­cused, and avoidance-focused coping strategies, with avoidance strategies being the most frequently reported

Negotiating local versus global needs in the International Long Term Ecological Research Network's socio-ecological research agenda

Over the past decade, Long-Term Socio-Ecological Research (LTSER) has been established to better integrate social science research and societal concerns into the goals and objectives of the International Long Term Ecological Research (ILTER) network, an established global network of long-term ecological monitoring sites. The Horizon 2020 eLTER project, currently underway, includes as one of its key objectives to evaluate the performance of LTSER platforms. This article reflects part of this evaluation: Six LTSER platforms were assessed through site visits of the lead author, coupled with reflections and insights of the platform managers, who are also coauthors. We provide background for the mission and goals of LTSER, and then assess the six international LTSER platforms – Baltimore Ecosystem Study LTER, USA; Braila Islands LTSER, Romania; Cairngorms LTSER, UK; Doñana LTSER, Spain; Omora Ethnobotanical Park Cape Horn LTER, Chile; and Sierra Nevada LTSER, Spain. 
 While based on a strong theoretical foundation in socio-ecological research, there has been a steep learning curve for scientists to apply the concept in practice at LTSER platforms. Key aspects of LTSER platforms have proven challenging, including management, interdisciplinary integration, and stakeholder collaboration. We characterize the tensions between top-down desires for network harmonization, bottom-up demands such as local policy relevance, and platform-level constraints such as time and budget. We discuss challenges, such as local context dominating the character of LTSER platforms, and the fact that scientists are disincentivized from engaging in transdisciplinary work. However, we also show positive impacts that have been achieved, including contributions to policy, land-use planning, and natural resource management. Overall, we conclude that while the international network offers important advantages to its members, a better balance between local and global goals could be achieved, and members may need to temper their expectations of what the network can and cannot offer at the local level

Mitochondrial DNA Copy Number and Incident Heart Failure: The Atherosclerosis Risk in Communities (ARIC) Study

Heart failure (HF) is a leading clinical and public health concern because of its high prevalence and poor prognosis. It is thus critical to identify novel risk factors for developing HF. Mitochondrial DNA copy number (mtDNA-CN), an indirect biomarker of mitochondrial dysfunction, is associated with atherosclerotic cardiovascular disease endpoints, cardiovascular risk factors, all-cause mortality, and sudden cardiac death. The association between mtDNA-CN and the risk of incident HF, however, is unknown. We examined this association in the Atherosclerosis Risk in Communities (ARIC) cohort

Radiation therapy and photodynamic therapy for biliary tract and ampullary carcinomas

The purpose of radiation therapy for unresectable biliary tract cancer is to prolong survival or prolong stent patency, and to provide palliation of pain. For unresectable bile duct cancer, there are a number of studies showing that radiation therapy is superior to the best supportive care. Although radiation therapy is used in many institutions, no large randomized controlled trials (RCTs) have been performed to date and the evidence level supporting the superiority of this treatment is low. Because long-term relief of jaundice is difficult without using biliary stenting, a combination of radiation therapy and stent placement is commonly used. As radiation therapy, external-beam radiation therapy is usually performed, but combined use of intraluminal brachytherapy with external beam radiation therapy is more useful for making the treatment more effective. There are many reports demonstrating improved response rates as well as extended survival and time to recurrence achieved by this combination therapy. Despite the low level of the evidence, this combination therapy is performed at many institutions. It is expected that multiinstitutional RCTs will be carried out. Unresectable gallbladder cancer with a large focus is usually extensive, and normal organs with high radio sensitivity exist contiguously with it. Therefore, only limited anticancer effects are to be expected from external beam radiation therapy for this type of cancer. The number of reports on ampullary cancer is small and the role of radiation therapy in this cancer has not been established. Combination treatment for ampullary cancer consists of either a single use of intraoperative radiation therapy, postoperative external beam radiation therapy or intraluminal brachytherapy, or a combination of two or three of these therapies. Intraoperative radiation therapy is superior in that it enables precise irradiation to the target site, thereby protecting adjacent highly radiosensitive normal tissues from irradiation. There are reports showing extended survival, although not significant, in groups undergoing intraoperative or postoperative radiation therapy compared with groups without radiation therapy. To date, there are no reports of large RCTs focusing on the significance of radiation therapy as a postoperative adjuvant treatment, so its usefulness as a postoperative adjuvant treatment is not proven. An alternative treatment is photodynamic therapy. There is an RCT demonstrating that, in unresectable bile duct cancer, extended survival and improved quality of life (QOL) have been achieved through a combination of photodynamic therapy and biliary stenting, compared with biliary stenting alone. Results from large RCTs are desired

Functionally oriented analysis of cardiometabolic traits in a trans-ethnic sample

Interpretation of genetic association results is difficult because signals often lack biological context. To generate hypotheses of the functional genetic etiology of complex cardiometabolic traits, we estimated the genetically determined component of gene expression from common variants using PrediXcan (1) and determined genes with differential predicted expression by trait. PrediXcan imputes tissue-specific expression levels from genetic variation using variant-level effect on gene expression in transcriptome data. To explore the value of imputed genetically regulated gene expression (GReX) models across different ancestral populations, we evaluated imputed expression levels for predictive accuracy genome-wide in RNA sequence data in samples drawn from European-Ancestry and African-Ancestry populations and identified substantial predictive power using European-derived models in a non-European target population.We then tested the association of GReX on 15 cardiometabolic traits including blood lipid levels, body mass index, height, blood pressure, fasting glucose and insulin, RR interval, fibrinogen level, factor VII level and white blood cell and platelet counts in 15 755 individuals across three ancestry groups, resulting in 20 novel gene-phenotype associations reaching experiment-wide significance across ancestries. In addition, we identified 18 significant novel gene-phenotype associations in our ancestry-specific analyses. Top associations were assessed for additional support via query of S-PrediXcan (2) results derived from publicly available genome-wide association studies summary data. Collectively, these findings illustrate the utility of transcriptome-based imputation models for discovery of cardiometabolic effect genes in a diverse dataset

Flowcharts for the management of biliary tract and ampullary carcinomas

No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography (US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting, chemotherapy, radiotherapy, and/or best supportive care is selected

A system for phenotype harmonization in the National Heart, Lung, and Blood Institute Trans-Omics for Precision Medicine (TOPMed) program

Genotype-phenotype association studies often combine phenotype data from multiple studies to increase statistical power. Harmonization of the data usually requires substantial effort due to heterogeneity in phenotype definitions, study design, data collection procedures, and data-set organization. Here we describe a centralized system for phenotype harmonization that includes input from phenotype domain and study experts, quality control, documentation, reproducible results, and data-sharing mechanisms. This system was developed for the National Heart, Lung, and Blood Institute’s Trans-Omics for Precision Medicine (TOPMed) program, which is generating genomic and other -omics data for more than 80 studies with extensive phenotype data. To date, 63 phenotypes have been harmonized across thousands of participants (recruited in 1948–2012) from up to 17 studies per phenotype. Here we discuss challenges in this undertaking and how they were addressed. The harmonized phenotype data and associated documentation have been submitted to National Institutes of Health data repositories for controlled access by the scientific community. We also provide materials to facilitate future harmonization efforts by the community, which include 1) the software code used to generate the 63 harmonized phenotypes, enabling others to reproduce, modify, or extend these harmonizations to additional studies, and 2) the results of labeling thousands of phenotype variables with controlled vocabulary terms

Genome-wide meta-analysis of muscle weakness identifies 15 susceptibility loci in older men and women

Low muscle strength is an important heritable indicator of poor health linked to morbidity and mortality in older people. In a genome-wide association study meta-analysis of 256,523 Europeans aged 60 years and over from 22 cohorts we identify 15 loci associated with muscle weakness (European Working Group on Sarcopenia in Older People definition: n = 48,596 cases, 18.9% of total), including 12 loci not implicated in previous analyses of continuous measures of grip strength. Loci include genes reportedly involved in autoimmune disease (HLA-DQA1p = 4 × 10−17), arthritis (GDF5p = 4 × 10−13), cell cycle control and cancer protection, regulation of transcription, and others involved in the development and maintenance of the musculoskeletal system. Using Mendelian randomization we report possible overlapping causal pathways, including diabetes susceptibility, haematological parameters, and the immune system. We conclude that muscle weakness in older adults has distinct mechanisms from continuous strength, including several pathways considered to be hallmarks of ageing