238 research outputs found

    An Improved Analysis of Forest Carbon Dynamics using Data Assimilation

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    There are two broad approaches to quantifying landscape C dynamics - by measuring changes in C stocks over time, or by measuring fluxes of C directly. However, these data may be patchy, and have gaps or biases. An alternative approach to generating C budgets has been to use process-based models, constructed to simulate the key processes involved in C exchange. However, the process of model building is arguably subjective, and parameters may be poorly defined. This paper demonstrates why data assimilation (DA) techniques - which combine stock and flux observations with a dynamic model - improve estimates of, and provide insights into, ecosystem carbon (C) exchanges. We use an ensemble Kalman filter (EnKF) to link a series of measurements with a simple box model of C transformations. Measurements were collected at a young ponderosa pine stand in central Oregon over a 3-year period, and include eddy flux and soil C02 efflux data, litterfall collections, stem surveys, root and soil cores, and leaf area index data. The simple C model is a mass balance model with nine unknown parameters, tracking changes in C storage among five pools; foliar, wood and fine root pools in vegetation, and also fresh litter and soil organic matter (SOM) plus coarse woody debris pools. We nested the EnKF within an optimization routine to generate estimates from the data of the unknown parameters and the five initial conditions for the pools. The efficacy of the DA process can be judged by comparing the probability distributions of estimates produced with the EnKF analysis vs. those produced with reduced data or model alone. Using the model alone, estimated net ecosystem exchange of C (NEE)= -251 f 197g Cm-2 over the 3 years, compared with an estimate of -419 f 29gCm-2 when all observations were assimilated into the model. The uncertainty on daily measurements of NEE via eddy fluxes was estimated at 0.5gCm-2 day-1, but the uncertainty on assimilated estimates averaged 0.47 g Cm-2 day-1, and only exceeded 0.5gC m-2 day-1 on days where neither eddy flux nor soil efflux data were available. In generating C budgets, the assimilation process reduced the uncertainties associated with using data or model alone and the forecasts of NEE were statistically unbiased estimates. The results of the analysis emphasize the importance of time series as constraints. Occasional, rare measurements of stocks have limited use in constraining the estimates of other components of the C cycle. Long time series are particularly crucial for improving the analysis of pools with long time constants, such as SOM, woody biomass, and woody debris. Long-running forest stem surveys, and tree ring data, offer a rich resource that could be assimilated to provide an important constraint on C cycling of slow pools. For extending estimates of NEE across regions, DA can play a further important role, by assimilating remote-sensing data into the analysis of C cycles. We show, via sensitivity analysis, how assimilating an estimate of photosynthesis - which might be provided indirectly by remotely sensed data - improves the analysis of NEE

    COVID-19: Impact on Business Students\u27 Transition from Face-to-Face to Online Instructional Delivery

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    ABSTRACT The COVID-19 pandemic has shaken the world to its proverbial core with institutions for higher learning caught in the crosshairs. Consequently, every facet of higher education has been indelibly affected. Traditional classroom instruction immediately changed, and a nontraditional delivery method emerged inclusive of both hybrid and online instruction. This delivery method was new to many students as all instruction shifted from face-to-face to virtual. To mitigate the spread of the virus, immediate action was required and campuses had to determine the probability of closing. This was a challenge for many reasons, some students did not have the resources to attend classes virtually. Many students had housing on campus that had been paid for the entire semester and were not prepared to suddenly switch to a new way of instruction and learning. Students depended on work-study on campus and library and computer resources to facilitate their course success. Administrators and educators realized that change is the constant we live within, and understood the need for strategies that were adaptive, agile, and would continue to meet the needs of all students. This change also signaled the need for innovative, contingent, and servant leadership strategies by administrators, faculty, and staff that reduced uncertainty and promoted care and stability for the students. This research paper aims to identify and share the experiences of business students enrolled in two institutions of higher education in meeting this challenge. It will also reveal how students dealt with the sudden transition from traditional learning environments to fully online and hybrid instruction. The complexity was intensified by the need to ensure that faculty members were prepared to give instruction virtually. Many were thrust into e-learning training which by most standards is a great way to demonstrate continuous improvement efforts, a major accreditation mandate for business schools. A Likert-scale survey was administered seeking responses to the processes of curriculum delivery; impact, problems, and issues experienced to the immediate shift to online instruction. Perceptions of support from faculty, advisors, administrators, and methods utilized to establish a sense of urgency to meet the educational needs of the students during COVID 19 were also assessed. Two-hundred and seventy-four students consented to complete the survey. Survey results provide benchmark experiences and challenges that business students encountered while completing their academic semesters. The results will assist business schools in developing best practices for virtual instruction, communication, and student engagement plans and strategies for facilitating student and faculty success during current waves of the pandemic and new pandemics of the future

    Disability and Health in African Americans: Population Research and Implications for Occupational Therapy Community-Based Practice

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    Background: Population-based research and community-based interventions are integral to occupational therapy’s scope of practice, yet they are underdeveloped in actual implementation. Therefore, this paper focuses on some health challenges facing the African American population, guided by the Person-Environment-Occupation-Performance Model. Method: Using data from an observational cross-sectional nationwide telephone survey of African American adults, we examined differences between African Americans who are receiving disability payments (RDP) and those who are employed full time (FTE) on several physical health behaviors and psychosocial health indicators. We further compared the differences between African Americans RDP versus those FTE on those physical health behaviors and psychosocial health indicators across five US regions. Results: Findings suggest that African Americans RDP are engaging in fewer positive physical health behaviors and experiencing worse psychosocial health compared to their counterparts FTE. There are also nuanced regional variations in the differences between African Americans RDP and FTE in physical health behaviors and psychosocial health indicators. Conclusion: This research highlighted some health challenges of African Americans RDP and FTE using a regional lens, demonstrating the value of OT population-based research. There is a need for OT population-specific community-based practice to address the health disparities of underserved and minority populations, such as African Americans

    Determinants of Asset Building

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    Determinants of Asset Buildin

    U.S. adolescent and adult women\u27s experiences accessing and using toilets in schools, workplaces, and public spaces: A multi-site focus group study to inform future research in bladder health

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    The World Health Organization recognizes access to clean and safe toilets as crucial for public health. This study explored U.S. adolescent and adult cisgender women\u27s lived experiences accessing toilets in schools, workplaces, and public spaces. As part of the Prevention of Lower Urinary Tract Symptoms (PLUS) Research Consortium, we conducted 44 focus groups with female participants (n = 360; ages 11-93). Focus groups were stratified by age (11-14, 15-17, 18-25, 26-44, 45-64, 65+) and conducted across 7 geographically diverse U.S. sites from July 2017-April 2018. Using a transdisciplinary approach, we conducted conventional qualitative coding informed by our PLUS conceptual framework and used content analysis processes to identify salient themes. Across settings, toilet access was restricted by gatekeepers (i.e., individuals who control access to toilets). In contrast, self-restricting toilet use (deciding not to use the toilet despite biologic need to urinate) was based on internalized norms to prioritize school and job responsibilities over urination. In public spaces, self-restricting use was largely in response to lack of cleanliness. Across the life course, participants perceived gender disparities in the ability to easily access public toilets. Further research is needed to determine if and how these factors impact bladder health across the life course

    Microbial impacts on 99mTc migration through sandstone under highly alkaline conditions relevant to radioactive waste disposal

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    Geological disposal of intermediate level radioactive waste in the UK is planned to involve the use of cementitious materials, facilitating the formation of an alkali-disturbed zone within the host rock. The biogeochemical processes that will occur in this environment, and the extent to which they will impact on radionuclide migration, are currently poorly understood. This study investigates the impact of biogeochemical processes on the mobility of the radionuclide technetium, in column experiments designed to be representative of aspects of the alkali-disturbed zone. Results indicate that microbial processes were capable of inhibiting 99mTc migration through columns, and X-ray radiography demonstrated that extensive physical changes had occurred to the material within columns where microbiological activity had been stimulated. The utilisation of organic acids under highly alkaline conditions, generating H2 and CO2, may represent a mechanism by which microbial processes may alter the hydraulic conductivity of a geological environment. Column sediments were dominated by obligately alkaliphilic H2-oxidising bacteria, suggesting that the enrichment of these bacteria may have occurred as a result of H2 generation during organic acid metabolism. The results from these experiments show that microorganisms are able to carry out a number of processes under highly alkaline conditions that could potentially impact on the properties of the host rock surrounding a geological disposal facility for intermediate level radioactive waste

    The Lantern Vol. 12, No. 3, June 1944

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    • A Peek Through a Byberry Window • Fragment • My Grudge Against the Fiction Detective • Haunting Refrain • The World and I • They Said • The Brook • By Their Fruits Ye Shall Know Them : 1944 Fogel Prize Essay • Why • Green Leaf • Night Drama • In That Same Hour • The Greeks Had a Word For It • The Call of War • The Promise of a Pearl • The Apiaryhttps://digitalcommons.ursinus.edu/lantern/1033/thumbnail.jp

    Prevention of Lower Urinary Tract Symptoms Research Consortium focus group Study of Habits, Attitudes, Realities, and Experiences of Bladder health

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    AimThe study purpose is to explore adolescent and adult women’s experiences, perceptions, beliefs, knowledge and behaviours related to bladder health across the life course using a socioecological perspective. Lower urinary tract symptoms affect between 20-40% of young adult to middle-aged women, with symptoms increasing in incidence and severity with aging. There is limited evidence to address bladder health promotion and prevention of dysfunction. This first study of the Prevention of Lower Urinary Tract Symptoms (PLUS) Research Consortium is designed to address gaps in existing qualitative research in this area.DesignThis focus group study will be implemented across seven geographically diverse United States research centres using a semi-structured focus group guide informed by a conceptual framework based on the socioecological model.MethodsThe study was approved in July 2017. A total of 44 focus groups composed of 6-8 participants representing six different age categories (ranging from 11 to over 65 years) will be completed. We aim to recruit participants with diverse demographic and personal characteristics including race, ethnicity, education, socioeconomic status, urban/rural residence, physical/health conditions, and urinary symptom experience. Six of the focus groups will be conducted in Spanish and translated into English. Focus group transcripts will undergo content analysis and data interpretation to identify and classify themes and articulate emerging themes.DiscussionThis foundational qualitative study seeks to develop an evidence base to inform future research on bladder health promotion in adolescent and adult women.ImpactThis study has the potential to provide new insights and understanding into adolescent and adult women’s lived experience of bladder health, the experience of lower urinary symptoms and knowledge and beliefs across the life course.ç ®ç æ ¬ç  ç©¶ç ç ®ç æ ¯ä» ç¤¾ä¼ ç æ å­¦ç è§ åº¦,æ ¢è®¨é å° å¹´å æ å¹´å¥³æ §å ¨äººç è¿ ç¨ ä¸­ä¸ è è ±å ¥åº·ç ¸å ³ç ç» éª ã è§ å¿µã 信念ã ç ¥è¯ å è¡ ä¸ºã ä¸ å°¿è·¯ç ç ¶å½±å 20-40%ç 中é å¹´å¥³æ §,é ç å¹´é¾ ç å¢ é ¿,ç ç ¶ç å ç ç å 严é ç¨ åº¦é ½å ¨å¢ é ¿ã å ³äº ä¿ è¿ è è ±å ¥åº·å é¢ é ²å è ½é ç¢ ç è¯ æ ®æ é ã æ ¬æ¬¡é¢ é ²ä¸ å°¿è·¯ç ç ¶(PLUS)ç  ç©¶è ç ç ç  ç©¶æ ¯é¦ ä¸ªå ³äº æ­¤æ ¹é ¢ç ç  ç©¶,æ ¨å ¨è§£å ³ç °æ ç å® æ §ç  ç©¶å ¨è¿ æ ¹é ¢ç å·®è· ã è®¾è®¡è¯¥é¡¹ç ¦ç ¹å° ç» ç  ç©¶å° å ¨ä¸ ä¸ªä¸ å ä½ ç½®ç ç¾ å ½ç  ç©¶ä¸­å¿ è¿ è¡ ,ä»¥å ºäº ç¤¾ä¼ ç æ 模å æ¦ å¿µæ¡ æ ¶ç å ç» æ å ç ç ¦ç ¹å° ç» æ å 为æ 导ã æ ¹æ³ è¯¥ç  ç©¶äº 2017å¹´7æ è ·å¾ æ ¹å ã ç ±6-8å 代表6ä¸ªä¸ å å¹´é¾ ç±»å «(ä» 11å² å °65å² ä»¥ä¸ )ç å ä¸ è ç» æ å ±44ä¸ªç ¦ç ¹å° ç» ã æ 们计å æ å ä¸ å äººå £å ä¸ªäººç ¹å¾ ç å ä¸ è ,ä¾ å¦ ç§ æ ã ç§ æ æ¸ æº ã æ è ²ç» å ã ç¤¾ä¼ ç» æµ å °ä½ ã å ä¹¡å± æ° ã èº«ä½ /å ¥åº·ç ¶å µå æ³ å°¿ç³»ç» ç ç ¶ç» å ã å ­ä¸ªç ¦ç ¹å° ç» ç ç  ç©¶å° ä»¥è¥¿ç ­ç è¯­è¿ è¡ ,å¹¶ç¿»è¯ æ è ±è¯­ã ç ¦ç ¹å° ç» ç èª æ ¬å° è¢«ç ¨äº å 容å æ å æ °æ ®è§£é ,ä»¥ç¡®å® å å ç±»ä¸»é¢ ,并é æ æ °å ºç °ç ä¸»é¢ ã è®¨è®ºè¿ é¡¹å ºç¡ æ §ç å® æ §ç  ç©¶æ ¨å ¨ä¸ºæ é« æ ªæ ¥é å° å¹´å æ å¹´å¦ å¥³ç è è ±å ¥åº·ç ç  ç©¶æ ä¾ è¯ æ ®å ºç¡ ã å½±å è¿ é¡¹ç  ç©¶æ å ¯è ½æ ä¾ å ³äº é å° å¹´å æ å¹´å¦ å¥³ç è è ±å ¥åº·ç ç æ´»ç» éª ,ç» éª ç ä¸ å°¿è·¯ç ç ¶å ç ¥è¯ å ç æ³ ç 人ç è¿ ç¨ ä¸­æ °ç è§ è§£å ç 解ãPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151981/1/jan14148_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151981/2/jan14148.pd

    Increased prevalence of pregnancy and comparative risk of program attrition among individuals starting HIV treatment in East Africa

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    Background The World Health Organization now recommends initiating all pregnant women on life-long antiretroviral therapy (ART), yet there is limited information about the characteristics and program outcomes of pregnant women already on ART in Africa. Our hypothesis was that pregnant women comprised an increasing proportion of those starting ART, and that sub-groups of these women were at higher risk for program attrition. Methods and findings We used the International Epidemiology Databases to Evaluate AIDS- East Africa (IeDEA-EA) to conduct a retrospective cohort study including HIV care and treatment programs in Kenya, Uganda, and Tanzania. The cohort consecutively included HIV-infected individuals 13 years or older starting ART 2004–2014. We examined trends over time in the proportion pregnant, their characteristics and program attrition rates compared to others initiating and already receiving ART. 156,474 HIV-infected individuals (67.0% women) started ART. The proportion of individuals starting ART who were pregnant women rose from 5.3% in 2004 to 12.2% in 2014. Mean CD4 cell counts at ART initiation, weighted for annual program size, increased from 2004 to 2014, led by non-pregnant women (annual increase 20 cells/mm3) and men (17 cells/mm3 annually), with lower rates of change in pregnant women (10 cells/mm3 per year) (p<0.0001). There was no significant difference in the cumulative incidence of program attrition at 6 months among pregnant women starting ART and non-pregnant women. However, healthy pregnant women starting ART (WHO stage 1/2) had a higher rate of attrition rate (9.6%), compared with healthy non-pregnant women (6.5%); in contrast among women with WHO stage 3/4 disease, pregnant women had lower attrition (8.4%) than non-pregnant women (14.4%). Among women who initiated ART when healthy and remained in care for six months, subsequent six-month attrition was slightly higher among pregnant women at ART start (3.5%) compared to those who were not pregnant (2.4%), (absolute difference 1.1%, 95% CI 0.7%-1.5%). Conclusions Pregnant women comprise an increasing proportion of those initiating ART in Africa, and pregnant women starting ART while healthy are at higher risk for program attrition than non-pregnant women. As ART programs further expand access to healthier pregnant women, further studies are needed to better understand the drivers of loss among this high risk group of women to optimize retention

    I never knew anyone who peed on themselves on purpose: Exploring adolescent and adult women’s lay language and discourse about bladder health and function

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    AimsThis analysis explored and characterized adolescent and adult women’s lay language and discourse related to bladder health/function.MethodsFortyâ four focus groups were conducted across seven United States research centers with 360 adolescents and adult women, organized by six age categories. Multilevel content analyses classified emergent themes. A transdisciplinary lens and inductive approach guided data interpretation. Interpretive insights were validated by a community engagement panel.ResultsA repertoire of bladder function terms emerged, including explicit functional terms, formal and polite euphemistic terms, and informal familiar terms, as well as cultural and regional metaphors and idioms. Terminology usage was historically grounded, developmental, and cumulative across the life course. Lay discourse was contextual and affectively valent, suggesting unspoken, commonly understood, situationâ based â rulesâ for talking about bladder function. Discourse appeared to be siloed within family and friendship circles. Adolescents and adult women often described, rather than named, bladder sensations or problems. Terminology for bladder issues tended to minimize severity and frequency, with medical language only relevant to extreme examples and not applicable to mild episodes.ConclusionsA definitional discordance between medical and lay views of bladder problems was identified, signifying a need to clarify the meaning of medical terms for lay persons. Adolescents and adult women do not have or use standardized precise terminology for bladder health and function, relying instead on social convention and interpersonal context. Findings can be used to foster shared understandings between lay persons and health professionals, informing development of clinical, research, and public health initiatives to promote bladder health.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153706/1/nau24174_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153706/2/nau24174.pd
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