Saturable nonlinear dielectric waveguide with applications to broad-area semiconductor lasers

Self-focusing in a passive dielectric waveguide with a saturable nonlinearity is studied. The eigensolutions constitute a good approximation to the lateral modes of broad-area semiconductor lasers under low-duty-cycle pulsed conditions. The laser modes are predicted to consist of adjacent filaments coupled in phase, leading to a single-lobed far field, and to be stable with increased current injection above saturation intensity. The ultimate filament spacing is inversely proportional to the threshold gain, and thus wider filaments are expected in low-threshold broad-area lasers

Negligence in the Air: The Duty of Care in Climate Change Litigation

The prospect of tort litigation against private parties has been gaining increasing attention by lawyers. While only three such cases have been filed thus far, observers (including the organizers of this symposium) clearly expect the number to increase significantly. Indeed, if successful, these and future cases will have a huge impact on the industries sued and, as hopeful lawyers have mused, could make the tobacco litigation look small by comparison. But will these cases succeed? As law students all dutifully learn in their first year Torts class, a prima facie negligence claim must satisfy four elements - duty, breach, causation, and injury. Most discussion and analysis of climate change cases to date have focused on the third and fourth elements of causation and injury. How can plaintiffs persuasively link the particular emissions of cars driven one place with reduced snow pack somewhere else? And, even if a causal link can be established between the offending action and the harm, what is the proper measure of the emitter\u27s liability in the face of multiple sources of greenhouse gases over an extended time period? These are challenging issues, and surely deserve careful attention. What remains surprising, though, is that little beyond passing mention has been written about the first two elements - the duty of care and its breach. Suppose one could establish that emissions from a utility company or an automobile manufacturer\u27s cars proximately caused greater storm surges that, in turn, harmed a particular coastal community, or proximately reduced snow pack and led to water shortages for a specific farming community. Key questions still remain. Did the utility or car manufacturer owe a duty of care to these specific communities? If so, what was the nature of that duty and was it breached? To improve our understanding of the short and long-term potential for climate change tort litigation, this article focuses on the duty of care and its breach. The first section addresses general doctrine. What role does the duty of care play in tort actions? The second section then explores the likely scenarios for tort climate actions, including a summary of the tort-based actions brought thus far. Who are the likely plaintiffs and defendants? How have litigants attempted to satisfy the duty of care elements in climate litigation? The final sections assess the duty of care for a range of tort actions-negligence, product liability, private nuisance and public nuisance-that may in the future form the basis of climate-based claims

Self-stabilized Nonlinear Lateral Modes of Broad Area Lasers

The lateral modes of broad area lasers are investigated theoretically. The nonlinear interaction between optical field and effective refractive index leads to a saturable nonlinearity in the governing field equation, so that self-modulated solutions are found to be stable with increased current injection above saturation intensity. We derive approximate analytical solutions for traveling wave fields within the broad area laser. The field amplitude consists of a small ripple superimposed on a large dc value. Matching fields at the boundary determines the modulation depth and imparts an overall phase curvature to the traveling wave mode. There are multiple lateral modes for a given set of operating conditions, and modes with successively more lobes in the ripple have greater overall phase curvature. In contrast to the linear problem, several lateral modes can achieve the same modal gain, for a given injected current density, by saturating the gain to different extent. Thus, these modes would exhibit slightly different optical powers

Erratum: The Non-Coding RNA Journal Club: Highlights on Recent Papers-4. Non-Coding RNA 2016, 2, 9.

Please note that in the published editorial [1], affiliations 1, and 8 contained errors.[...]

Improving Sensitivity to and Inclusivity of LGBT Older Adults in an Urban Geriatric Practice

CHA’s overall goal is to improve the care delivered to LGBT older adults. Step 1: Needs assessment with provider and staff survey (Fall 2020)Step 2: Implementation of SAGE training and provider education (Fall/Winter 2020) Step 3 (this study): Needs assessment with community-dwelling LGBT older adults (Spring 2021

Interprofessional Student Hotspotting Project

Background: IPE and Practice-based Learning It is well established that there is a need for Interprofessional Education (IPE) in the current landscape of health education1 and students that participate in IPE enjoy these experiences and develop skills in interprofessional teamwork that prepare them for future team-based practice.2,3,4 IPE, however, is not standardized. It ranges from programs that teach theoretical frameworks in a classroom setting to others that allow interprofessional teams of students to work together in a clinical setting.5,6 The second form is referred to as practice-based learning (PrBL).3 PrBL is now considered by experts as one of the most effective teaching methods.3,6 Unfortunately, due to the lack of consistency of IPE programs and the lack of standardization in IPE research, there is inconsistency in data regarding the best IPE method.6,

Examining High and Low Value-Added Mathematics Instruction: Can Expert Observers Tell the Difference

The question of how to measure effective teachers and teaching has long been of interest to policymakers and school leaders. While recent policy initiatives have focused on the use of value-added measures (VAM) to assess teacher quality, there is a much longer tradition of using observations of practice to make such determinations. However, empirical evidence suggests these two indicators often identify different sets of teachers as effective. For example, the Measures of Effective Teaching project finds low correlations between teachers’ VAM scores and their quality of instruction as measured by observational metrics. Studies with the explicit intent of identifying differences in instruction between teachers with high and low VAM scores also have generally failed to uncover substantial differences across classrooms. In this study, we take advantage of a dataset containing both videotaped lessons and value-added scores to mount an exploratory study of the instruction of teachers with high- and low-value-added rankings. Specifically, we seek to answer two questions: First, what is the degree of convergence between observers’ impressions of mathematics instruction and teachers’ mathematics value-added scores? Second, are there a set of instructional practices that consistently characterize high but not low-value-added ranked teachers’ classrooms, and vice versa

A screen of Crohn's disease-associated microbial metabolites identifies ascorbate as a novel metabolic inhibitor of activated human T cells.

Microbial metabolites are an emerging class of mediators influencing CD4+ T-cell function. To advance the understanding of direct causal microbial factors contributing to Crohn's disease, we screened 139 predicted Crohn's disease-associated microbial metabolites for their bioactivity on human CD4+ T-cell functions induced by disease-associated T helper 17 (Th17) polarizing conditions. We observed 15 metabolites with CD4+ T-cell bioactivity, 3 previously reported, and 12 unprecedented. A deeper investigation of the microbe-derived metabolite, ascorbate, revealed its selective inhibition on activated human CD4+ effector T cells, including IL-17A-, IL-4-, and IFNγ-producing cells. Mechanistic assessment suggested the apoptosis of activated human CD4+ T cells associated with selective inhibition of energy metabolism. These findings suggest a substantial rate of relevant T-cell bioactivity among Crohn's disease-associated microbial metabolites, and evidence for novel modes of bioactivity, including targeting of T-cell energy metabolism

Using second harmonic generation to predict patient outcome in solid tumors

Abstract Background Over-treatment of estrogen receptor positive (ER+), lymph node-negative (LNN) breast cancer patients with chemotherapy is a pressing clinical problem that can be addressed by improving techniques to predict tumor metastatic potential. Here we demonstrate that analysis of second harmonic generation (SHG) emission direction in primary tumor biopsies can provide prognostic information about the metastatic outcome of ER+, LNN breast cancer, as well as stage 1 colorectal adenocarcinoma. Methods SHG is an optical signal produced by fibrillar collagen. The ratio of the forward-to-backward emitted SHG signals (F/B) is sensitive to changes in structure of individual collagen fibers. F/B from excised primary tumor tissue was measured in a retrospective study of LNN breast cancer patients who had received no adjuvant systemic therapy and related to metastasis-free survival (MFS) and overall survival (OS) rates. In addition, F/B was studied for its association with the length of progression-free survival (PFS) in a subgroup of ER+ patients who received tamoxifen as first-line treatment for recurrent disease, and for its relation with OS in stage I colorectal and stage 1 lung adenocarcinoma patients. Results In 125 ER+, but not in 96 ER-negative (ER-), LNN breast cancer patients an increased F/B was significantly associated with a favorable MFS and OS (log rank trend for MFS: p = 0.004 and for OS: p = 0.03). On the other hand, an increased F/B was associated with shorter PFS in 60 ER+ recurrent breast cancer patients treated with tamoxifen (log rank trend p = 0.02). In stage I colorectal adenocarcinoma, an increased F/B was significantly related to poor OS (log rank trend p = 0.03), however this relationship was not statistically significant in stage I lung adenocarcinoma. Conclusion Within ER+, LNN breast cancer specimens the F/B can stratify patients based upon their potential for tumor aggressiveness. This offers a “matrix-focused” method to predict metastatic outcome that is complementary to genomic “cell-focused” methods. In combination, this and other methods may contribute to improved metastatic prediction, and hence may help to reduce patient over-treatment.http://deepblue.lib.umich.edu/bitstream/2027.42/116036/1/12885_2015_Article_1911.pd