2,553 research outputs found
Semiconductor structure and devices
Semiconductor devices such as lasers which include a substrate with a channel therein with a clad layer overlying the substrate and filling the channel exhibit irregularities such as terraces in the surface of the clad layer which are detrimental to device performance. These irregularities are substantially eliminated by forming the channel in a surface of a buffer layer greater than about 4 micrometers thick on the substrate and forming the clad layer over the buffer layer and the channel. CW lasers incorporating the principles of the invention exhibit the highest output power in a single spatial mode and maximum output power which have been observed to date
A Delphi process to address medication appropriateness for older persons with multiple chronic conditions
BACKGROUND: Frameworks exist to evaluate the appropriateness of medication regimens for older patients with multiple medical conditions (MCCs). Less is known about how to translate the concepts of the frameworks into specific strategies to identify and remediate inappropriate regimens.
METHODS: Modified Delphi method involving iterative rounds of input from panel members. Panelists (n = 9) represented the disciplines of nursing, medicine and pharmacy. Included among the physicians were two geriatricians, one general internist, one family practitioner, one cardiologist and two nephrologists. They participated in 3 rounds of web-based anonymous surveys.
RESULTS: The panel reached consensus on a set of markers to identify problems with medication regimens, including patient/caregiver report of non-adherence, medication complexity, cognitive impairment, medications identified by expert opinion as inappropriate for older persons, excessively tight blood sugar and blood pressure control among persons with diabetes mellitus, patient/caregiver report of adverse medication effects or medications not achieving desired outcomes, and total number of medications. The panel also reached consensus on approaches to address these problems, including endorsement of strategies to discontinue medications with known benefit if necessary because of problems with feasibility or lack of alignment with patient goals.
CONCLUSIONS: The results of the Delphi process provide the basis for an algorithm to improve medication regimens among older persons with MCCs. The algorithm will require assessment not only of medications and diagnoses but also cognition and social support, and it will support discontinuation of medications both when risks outweigh benefits and when regimens are not feasible or do not align with goals
The Demand for Carbon Offsets in the United States: A Snapshot of U.S. Buyers on the Global Voluntary and California Compliance Markets
While the supply-side of carbon markets is relatively well documented, understanding of demand is more elusive. This report aims to shed light on the demand for carbon offsets in the United States, both among companies purchasing offsets voluntarily and California entities purchasing offsets as part of their compliance obligations under the new greenhouse gas regulation in the state. Our research focuses on three key areas of inquiry:
(1) Motivations: Why are firms choosing to purchase carbon offsets?
(2) Processes: How are firms navigating the carbon markets? What decision-making processes are firms using when purchasing offsets? What barriers and challenges are firms facing?
(3) Preferences: What preferences do buyers exhibit when purchasing offsets? What factors do firms consider when investing in an offset project or portfolio of projects?
To answer these questions, we surveyed compliance companies in California, did case studies of five major companies purchasing offsets on the voluntary market, and interviewed dozens of buyers and other market participants.
On the voluntary side, we found that companies were motivated largely by corporate social responsibility and public relations. Although each company had different goals for their offsetting program, they all reaped benefits in terms of both environmental sustainability and improved branding. The case studies of Ford, Macmillan, Interface, General Motors, and British Petroleum illustrate several different approaches toward offsetting. In terms of process, we found that most voluntary buyers purchase offsets as part of larger sustainability efforts and spend considerable time and effort quantifying their emissions and defining program goals. They then work with NGOs, consultants, and other advisors to build their offset strategies accordingly. Lastly, in terms of preferences, we found that companies in the voluntary market prefer offsets that are highly visible, have an immediate impact, and pose a low public relations risk. They tend to buy a diverse portfolio of offsets, some of which are “charismatic” and others that are cheaper and/or available in bulk.
In the California compliance market, companies are motivated entirely by the AB32 regulation, which requires them to meet an emissions cap. To do so, they have the option to reduce their emissions, purchase allowances, purchase offsets, or do a combination of the three to comply with the law. Since offsets are cheaper than allowances, many compliant entities plan to purchase offsets as a way to reduce costs; however, there may be hidden transaction costs in figuring out how to navigate the offset marketplace. We found that overall, compliance entities are very price-sensitive, with recommendations from partners being a secondary consideration. The projected supply of offsets and differentiated risk across project types may also influence demand for offsets on the California market.Master of ScienceNatural Resources and EnvironmentUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/97426/1/Carbon Offset Demand in the US_Final_April 2013.pd
Supporting Family Physician Maternity Care Providers
Maternity care access in the United States is in crisis. The American Congress of Obstetrics and Gynecology projects that by 2030 there will be a nationwide shortage of 9,000 obstetrician-gynecologists (OB/GYNs). Midwives and OB/GYNs have been called upon to address this crisis, yet in underserved areas, family physicians are often providing a majority of this care. Family medicine maternity care, a natural fit for the discipline, has been on sharp decline in recent years for many reasons including difficulties cultivating interdisciplinary relationships, navigating privileging, developing and maintaining adequate volume/competency, and preventing burnout. In 2016 and 2017, workshops were held among family medicine educators with resultant recommendations for essential strategies to support family physician maternity care providers. This article summarizes these strategies, provides guidance, and highlights the role family physicians have in addressing maternity care access for the underserved as well as presenting innovative ideas to train and retain rural family physician maternity care providers
Emisari: a management information system designed to aid and involve people
The EMISARI System described in this paper represents a major departure from conventional MIS design. It is oriented not toward data per se, but rather toward activities of the people who generate and use the data. Thus it provides not merely for reporting up the chain of command, but also for dissemination of policy guidance and reference material down the chain, and for lateral communication among all users. It places a premium upon flexibility, to permit rapid system modifications in response to changes in user functions and needs and it offers a greatly simplified operation, to avoid any necessity for extensive user training or complex operation manuals. The overall approach may be viewed as a greatly modernized version of the classic telephone party line, using a computer to organize, selectively sort, and store-and-forward a constant flow of statistics, messages, estimates, reference materials, guidelines, notices, and other informational accountrements of a modern management operation
Genetic Association Analysis Using Sibship Data: A Multilevel Model Approach
Family based association study (FBAS) has the advantages of controlling for population stratification and testing for linkage and association simultaneously. We propose a retrospective multilevel model (rMLM) approach to analyze sibship data by using genotypic information as the dependent variable. Simulated data sets were generated using the simulation of linkage and association (SIMLA) program. We compared rMLM to sib transmission/disequilibrium test (S-TDT), sibling disequilibrium test (SDT), conditional logistic regression (CLR) and generalized estimation equations (GEE) on the measures of power, type I error, estimation bias and standard error. The results indicated that rMLM was a valid test of association in the presence of linkage using sibship data. The advantages of rMLM became more evident when the data contained concordant sibships. Compared to GEE, rMLM had less underestimated odds ratio (OR). Our results support the application of rMLM to detect gene-disease associations using sibship data. However, the risk of increasing type I error rate should be cautioned when there is association without linkage between the disease locus and the genotyped marker
Pediatric patients with multi-organ dysfunction syndrome receiving continuous renal replacement therapy
Pediatric patients with multi-organ dysfunction syndrome receiving continuous renal replacement therapy.BackgroundCritical illness leading to multi-organ dysfunction syndrome (MODS) and associated acute renal failure (ARF) is less common in children compared to adult patients. As a result, many issues plague the pediatric ARF outcome literature, including a relative lack of prospective study, a lack of modality stratification in subject populations and inconsistent controls for patient illness severity in outcome analysis.MethodsWe now report data from the first multicenter study to assess the outcome of pediatric patients with MODS receiving continuous renal replacement therapy (CRRT). One hundred twenty of 157 Registry patients (63 male/57 female) experienced MODS during their course.ResultsOne hundred sixteen patients had complete data available for analysis. The most common causes leading to CRRT were sepsis (N = 47; 39.2%) and cardiogenic shock (N = 24; 20%). Overall survival was 51.7%. Pediatric Risk of Mortality (PRISM 2) score, central venous pressure (CVP), and% fluid overload (%FO) at CRRT initiation were significantly lower for survivors versus nonsurvivors. Multivariate analysis controlling for severity of illness using PRISM 2 at CRRT initiation revealed that%FO was still significantly lower for survivors versus nonsurvivors (P < 0.05) even for patients receiving both mechanical ventilation and vasoactive pressors. We speculate that increased fluid administration from PICU admission to CRRT initiation is an independent risk factor for mortality in pediatric patients with MODS receiving CRRT.ConclusionWe suggest that after initial resuscitative efforts, an increased emphasis should be placed on early initiation of CRRT and inotropic agent use over fluid administration to maintain acceptable blood pressure
A metastasis biomarker (MetaSite Breast™ Score) is associated with distant recurrence in hormone receptor-positive, HER2-negative early-stage breast cancer
Metastasis is the primary cause of death in early-stage breast cancer. We evaluated the association between a metastasis biomarker, which we call "Tumor Microenviroment of Metastasis" (TMEM), and risk of recurrence. TMEM are microanatomic structures where invasive tumor cells are in direct contact with endothelial cells and macrophages, and which serve as intravasation sites for tumor cells into the circulation. We evaluated primary tumors from 600 patients with Stage I-III breast cancer treated with adjuvant chemotherapy in trial E2197 (NCT00003519), plus endocrine therapy for hormone receptor (HR)+ disease. TMEM were identified and enumerated using an analytically validated, fully automated digital pathology/image analysis method (MetaSite Breast™), hereafter referred to as MetaSite Score (MS). The objectives were to determine the association between MS and distant relapse free interval (DRFI) and relapse free interval (RFI). MS was not associated with tumor size or nodal status, and correlated poorly with Oncotype DX Recurrence Score (r = 0.29) in 297 patients with HR+/HER2- disease. Proportional hazards models revealed a significant positive association between continuous MS and DRFI (p = 0.001) and RFI (p = 0.00006) in HR+/HER2- disease in years 0-5, and by MS tertiles for DRFI (p = 0.04) and RFI (p = 0.01), but not after year 5 or in triple negative or HER2+ disease. Multivariate models in HR+/HER- disease including continuous MS, clinical covariates, and categorical Recurrence Score ( 30) showed MS is an independent predictor for 5-year RFI (p = 0.05). MetaSite Score provides prognostic information for early recurrence complementary to clinicopathologic features and Recurrence Score.Breast Cancer Research Foundatio
Prognostic Value of Tumor-Infiltrating Lymphocytes in Triple-Negative Breast Cancers From Two Phase III Randomized Adjuvant Breast Cancer Trials: ECOG 2197 and ECOG 1199
Purpose
Recent studies suggest that tumor-infiltrating lymphocytes (TILs) are associated with disease-free (DFS) and overall survival (OS) in operable triple-negative breast cancer (TNBC). We seek to validate the prognostic impact of TILs in primary TNBCs in two adjuvant phase III trials conducted by the Eastern Cooperative Oncology Group (ECOG).
Patients and Methods
Full-face hematoxylin and eosin–stained sections of 506 tumors from ECOG trials E2197 and E1199 were evaluated for density of TILs in intraepithelial (iTILs) and stromal compartments (sTILs). Patient cases of TNBC from E2197 and E1199 were randomly selected based on availability of sections. For the primary end point of DFS, association with TIL scores was determined by fitting proportional hazards models stratified on study. Secondary end points were OS and distant recurrence–free interval (DRFI). Reporting recommendations for tumor marker prognostic studies criteria were followed, and all analyses were prespecified.
Results
The majority of 481 evaluable cancers had TILs (sTILs, 80%; iTILs, 15%). With a median follow-up of 10.6 years, higher sTIL scores were associated with better prognosis; for every 10% increase in sTILs, a 14% reduction of risk of recurrence or death (P = .02), 18% reduction of risk of distant recurrence (P = .04), and 19% reduction of risk of death (P = .01) were observed. Multivariable analysis confirmed sTILs to be an independent prognostic marker of DFS, DRFI, and OS.
Conclusion
In two national randomized clinical trials using contemporary adjuvant chemotherapy, we confirm that stromal lymphocytic infiltration constitutes a robust prognostic factor in TNBCs. Studies assessing outcomes and therapeutic efficacies should consider stratification for this parameter
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