187 research outputs found

    Resonant absorption in semiconductor nanowires and nanowire arrays: Relating leaky waveguide modes to Bloch photonic crystal modes

    Get PDF
    We present a unified framework for resonant absorption in periodic arrays of high index semiconductor nanowires that combines a leaky waveguide theory perspective and that of photonic crystals supporting Bloch modes, as array density transitions from sparse to dense. Full dispersion relations are calculated for each mode at varying illumination angles using the eigenvalue equation for leaky waveguide modes of an infinite dielectric cylinder. The dispersion relations along with symmetry arguments explain the selectivity of mode excitation and spectral red-shifting of absorption for illumination parallel to the nanowire axis in comparison to perpendicular illumination. Analysis of photonic crystal band dispersion for varying array density illustrates that the modes responsible for resonant nanowire absorption emerge from the leaky waveguide modes

    Aligning Business Decision Making to Strategy

    Get PDF
    Hurry up and wait is a recipe for inefficiency. Some product development projects start and stop and start again, with team members being added and removed throughout the process. The cost of this lurching does not appear to be well quantified. Moving technical talent from one project to another may assume 100% engineering efficiency, which is not case. Hidden effects of engineers being moved include having to spin up on the new project and learn where the last team members left off (which may not be well documented), repeating initial work, and lowered efficiency and morale on the part of the engineers if the reason behind the moves was not well communicated or understood. A lack of clear strategic intent leads to people or money being shifted between projects frequently and inefficiently. In the case of a project being completely shut down due to the shift, the short term effects are fairly obvious: the old project is stopped and will not complete until it is started up again. The long term effects could include opportunity costs of missed sales and additional cost to pull the project out of mothballs. When a project is not completely shut down, the effects are more difficult to quantify. Were the resources moved subject matter experts? Is the increase in schedule a one for one match or something more substantial

    An Inquiry into Pennsylvania’s Keystone STARS: Research Report

    Get PDF
    A team from the University of Pennsylvania was funded by the William Penn Foundation to conduct an inquiry of Keystone STARS. The goal of this inquiry was to provide a broad look at Keystone STARS to inform future revisions and evaluation of the system as part of Pennsylvania’s Race to the Top Early Learning Challenge grant (2013-2018). The inquiry focused on providing an overarching look at Keystone STARS with respect to three major areas and presents a detailed review of the data and findings for each of the three aspects: Child outcomes: examining the relations between Keystone STARS and children’s overall developmental competencies. Quality components: investigating the extent of evidence from theory, empirical research, and practitioner expertise linking each of the Keystone STARS quality components to child outcomes. Systems approach to rating quality and guiding improvements: examining overall features of the system that could be improved to enhance the effectiveness and efficiency of the system. The authors conclude with an overview of the lessons learned and point to promising areas of reform for improving Keystone STARS for the children of Pennsylvania

    Interplay between ESR1/PIK3CA codon variants, oncogenic pathway alterations and clinical phenotype in patients with metastatic breast cancer (MBC): Comprehensive circulating tumor DNA (ctDNA) analysis

    Get PDF
    BACKGROUND: although being central for the biology and druggability of hormone-receptor positive, HER2 negative metastatic breast cancer (MBC), ESR1 and PIK3CA mutations are simplistically dichotomized as mutated or wild type in current clinical practice. METHODS: The study analyzed a multi-institutional cohort comprising 703 patients with luminal-like MBC characterized for circulating tumor DNA through next generation sequencing (NGS). Pathway classification was defined based on previous work (i.e., RTK, RAS, RAF, MEK, NRF2, ER, WNT, MYC, P53, cell cycle, notch, PI3K). Single nucleotide variations (SNVs) were annotated for their oncogenicity through OncoKB. Only pathogenic variants were included in the models. Associations among clinical characteristics, pathway classification, and ESR1/PIK3CA codon variants were explored. RESULTS: The results showed a differential pattern of associations for ESR1 and PIK3CA codon variants in terms of co-occurring pathway alterations patterns of metastatic dissemination, and prognosis. ESR1 537 was associated with SNVs in the ER and RAF pathways, CNVs in the MYC pathway and bone metastases, while ESR1 538 with SNVs in the cell cycle pathway and liver metastases. PIK3CA 1047 and 542 were associated with CNVs in the PI3K pathway and with bone metastases. CONCLUSIONS: The study demonstrated how ESR1 and PIK3CA codon variants, together with alterations in specific oncogenic pathways, can differentially impact the biology and clinical phenotype of luminal-like MBC. As novel endocrine therapy agents such as selective estrogen receptor degraders (SERDS) and PI3K inhibitors are being developed, these results highlight the pivotal role of ctDNA NGS to describe tumor evolution and optimize clinical decision making

    Factors associated with the utilization of community dental services among newly incarcerated adults

    Get PDF
    Background: Given the high rates of risky behaviors and health conditions among incarcerated individuals and the relationship between oral and general health, receipt of quality dental care is essential to the overall health and well-being of this population. However, few recent studies have focused on access to care and the state of oral health among incarcerated populations in the U.S. For the current study, a secondary data analysis was conducted to: 1) assess factors associated with the use of dental services among a newly incarcerated prison population in Georgia and 2) consider barriers related to utilization of dental services pre- to post-release. Methods: Descriptive statistics were calculated, and bivariate and logistic regression analyses were conducted utilizing SAS 9.2 software. Results: Thirty-one percent (n=250) of survey respondents reported having a dental visit within the past year. Survey respondents who had a regular dentist (OR: 1.9; 95% CI: 1.325, 2.697), private dental insurance (OR: 1.5; 95% CI: 1.022, 2.245), or who reported pain as the reason for their last dental visit (OR: 2.2; 95% CI: 1.556, 3.130) were more likely to have utilized dental services within the past year. Conclusions: The findings highlight the role of social and economic resources and oral health needs on utilization of dental services. Additional practice and policy efforts are needed to address gaps in the dental care continuum that affect currently and formerly incarcerated adults in Georgia

    Circulating tumour DNA characterisation of invasive lobular carcinoma in patients with metastatic breast cancer

    Get PDF
    BACKGROUND: Limited data exist to characterise molecular differences in circulating tumour DNA (ctDNA) for patients with invasive lobular carcinoma (ILC). We analysed metastatic breast cancer patients with ctDNA testing to assess genomic differences among patients with ILC, invasive ductal carcinoma (IDC), and mixed histology. METHODS: We retrospectively analysed 980 clinically annotated patients (121 ILC, 792 IDC, and 67 mixed histology) from three academic centers with ctDNA evaluation by Guardant360™. Single nucleotide variations (SNVs), copy number variations (CNVs), and oncogenic pathways were compared across histologies. FINDINGS: ILC was significantly associated with HR+ HER2 negative and HER2 low. SNVs were higher in patients with ILC compared to IDC or mixed histology (Mann Whitney U test, P \u3c 0.05). In multivariable analysis, HR+ HER2 negative ILC was significantly associated with mutations in CDH1 (odds ratio (OR) 9.4, [95% CI 3.3-27.2]), ERBB2 (OR 3.6, [95% confidence interval (CI) 1.6-8.2]), and PTEN (OR 2.5, [95% CI 1.05-5.8]) genes. CDH1 mutations were not present in the mixed histology cohort. Mutations in the PI3K pathway genes (OR 1.76 95% CI [1.18-2.64]) were more common in patients with ILC. In an independent cohort of nearly 7000 metastatic breast cancer patients, CDH1 was significantly co-mutated with targetable alterations (PIK3CA, ERBB2) and mutations associated with endocrine resistance (ARID1A, NF1, RB1, ESR1, FGFR2) (Benjamini-Hochberg Procedure, all q \u3c 0.05). INTERPRETATION: Evaluation of ctDNA revealed differences in pathogenic alterations and oncogenic pathways across breast cancer histologies with implications for histologic classification and precision medicine treatment. FUNDING: Lynn Sage Cancer Research Foundation, OncoSET Precision Medicine Program, and UL1TR001422

    The Problem of the Color Line: Spatial Access to Hospital Services for Minoritized Racial and Ethnic Groups

    Get PDF
    Examining how spatial access to health care varies across geography is key to documenting structural inequalities in the United States. In this article and the accompanying StoryMap, our team identified ZIP Code Tabulation Areas (ZCTAs) with the largest share of minoritized racial and ethnic populations and measured distances to the nearest hospital offering emergency services, trauma care, obstetrics, outpatient surgery, intensive care, and cardiac care. In rural areas, ZCTAs with high Black or American Indian/Alaska Native representation were significantly farther from services than ZCTAs with high White representation. The opposite was true for urban ZCTAs, with high White ZCTAs being farther from most services. These patterns likely result from a combination of housing policies that restrict housing opportunities and federal health policies that are based on service provision rather than community need. The findings also illustrate the difficulty of using a single metric—distance—to investigate access to care on a national scale

    Effect of physical activity, social support, and skills training on late-life emotional health: a systematic literature review and implications for public health research

    Get PDF
    Purpose: Given that emotional health is a critical component of healthy aging, we undertook a systematic literature review to assess whether current interventions can positively affect older adults’ emotional health. Methods: A national panel of health services and mental health researchers guided the review. Eligibility criteria included community-dwelling older adult (aged ≥ 50 years) samples, reproducible interventions, and emotional health outcomes, which included multiple domains and both positive (well-being) and illness-related (anxiety) dimensions. This review focused on three types of interventions – physical activity, social support, and skills training – given their public health significance and large number of studies identified. Panel members evaluated the strength of evidence (quality and effectiveness). Results: In all, 292 articles met inclusion criteria. These included 83 exercise/physical activity, 25 social support, and 40 skills training interventions. For evidence rating, these 148 interventions were categorized into 64 pairings by intervention type and emotional health outcome, e.g., strength training targeting loneliness or social support to address mood. 83% of these pairings were rated at least fair quality. Expert panelists found sufficient evidence of effectiveness only for skills training interventions with health outcomes of decreasing anxiety and improving quality of life and self-efficacy. Due to limitations in reviewed studies, many intervention–outcome pairings yielded insufficient evidence. Conclusion: Skills training interventions improved several aspects of emotional health in community-dwelling older adults, while the effects for other outcomes and interventions lacked clear evidence. We discuss the implications and challenges in moving forward in this important area
    • …
    corecore