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Over recent decades, biomass gains in remaining old-growth Amazonia forests have declined due to environmental change. Amazonia’s huge size and complexity makes understanding these changes, drivers, and consequences very challenging. Here, using a network of permanent monitoring plots at the Amazon–Cerrado transition, we quantify recent biomass carbon changes and explore their environmental drivers. Our study area covers 30 plots of upland and riparian forests sampled at least twice between 1996 and 2016 and subject to various levels of fire and drought. Using these plots, we aimed to: (1) estimate the long-term biomass change rate; (2) determine the extent to which forest changes are influenced by forest type; and (3) assess the threat to forests from ongoing environmental change. Overall, there was no net change in biomass, but there was clear variation among different forest types. Burning occurred at least once in 8 of the 12 riparian forests, while only 1 of the 18 upland forests burned, resulting in losses of carbon in burned riparian forests. Net biomass gains prevailed among other riparian and upland forests throughout Amazonia. Our results reveal an unanticipated vulnerability of riparian forests to fire, likely aggravated by drought, and threatening ecosystem conservation at the Amazon southern margins.
Kochia is one of the most problematic weeds in the United States. Field studies were conducted in five states (Wyoming, Colorado, Kansas, Nebraska, and South Dakota) over 2 yr (2010 and 2011) to evaluate kochia control with selected herbicides registered in five common crop scenarios: winter wheat, fallow, corn, soybean, and sugar beet to provide insight for diversifying kochia management in crop rotations. Kochia control varied by experimental site such that more variation in kochia control and biomass production was explained by experimental site than herbicide choice within a crop. Kochia control with herbicides currently labeled for use in sugar beet averaged 32% across locations. Kochia control was greatest and most consistent from corn herbicide programs (99%), followed by soybean (96%) and fallow (97%) herbicide programs. Kochia control from wheat herbicide programs was 93%. With respect to the availability of effective herbicide options, glyphosate-resistant kochia control was easiest in corn, soybean, and fallow, followed by wheat; and difficult to manage with herbicides in sugar beet.
There is a clear need to educate and train the clinical research workforce to conduct scientifically sound clinical research. Meeting this need requires the creation of tools to assess both an individual’s preparedness to function efficiently in the clinical research enterprise and tools to evaluate the quality and effectiveness of programs that are designed to educate and train clinical research professionals. Here we report the development and validation of a competency self-assessment entitled the Competency Index for Clinical Research Professionals, version II (CICRP-II).
CICRP-II was developed using data collected from clinical research coordinators (CRCs) participating in the “Development, Implementation and Assessment of Novel Training In Domain-Based Competencies” (DIAMOND) project at four clinical and translational science award (CTSA) hubs and partnering institutions.
An exploratory factor analysis (EFA) identified a two-factor structure: the first factor measures self-reported competence to perform Routine clinical research functions (e.g., good clinical practice regulations (GCPs)), while the second factor measures competence to perform Advanced clinical functions (e.g., global regulatory affairs). We demonstrate the between groups validity by comparing CRCs working in different research settings.
The excellent psychometric properties of CICRP-II and its ability to distinguish between experienced CRCs at research-intensive CTSA hubs and CRCs working in less-intensive community-based sites coupled with the simplicity of alternative methods for scoring respondents make it a valuable tool for gauging an individual’s perceived preparedness to function in the role of CRC as well as an equally valuable tool to evaluate the value and effectiveness of clinical research education and training programs.
Decreases in cognitive function related to increases in oxidative stress and inflammation occur with ageing. Acknowledging the free radical-quenching activity and anti-inflammatory action of the carotenoid lycopene, the aim of the present review was to assess if there is evidence for a protective relationship between lycopene and maintained cognitive function or between lycopene and development or progression of dementia. A systematic literature search identified five cross-sectional and five longitudinal studies examining these outcomes in relation to circulating or dietary lycopene. Among four studies evaluating relationships between lycopene and maintained cognition, three reported significant positive relationships. Neither of the two studies reporting on relationship between lycopene and development of dementia reported significant results. Of four studies investigating circulating lycopene and pre-existing dementia, only one reported significant associations between lower circulating lycopene and higher rates of Alzheimer's disease mortality. Acknowledging heterogeneity among studies, there is insufficient evidence and a paucity of data to draw firm conclusions or tease apart direct effects of lycopene. Nevertheless, as low circulating lycopene is a predictor of all-cause mortality, further investigation into its relationship with cognitive longevity and dementia-related mortality is warranted.
The majority of self-management interventions are designed with a narrow focus on patient skills and fail to consider their potential as “catalysts” for improving care delivery. A project was undertaken to develop a patient self-management resource to support evidence-based, person-centered care for cancer pain and overcome barriers at the levels of the patient, provider, and health system.
The project used a mixed-method design with concurrent triangulation, including the following: a national online survey of current practice; two systematic reviews of cancer pain needs and education; a desktop review of online patient pain diaries and other related resources; consultation with stakeholders; and interviews with patients regarding acceptability and usefulness of a draft resource.
Findings suggested that an optimal self-management resource should encourage pain reporting, build patients’ sense of control, and support communication with providers and coordination between services. Each of these characteristics was identified as important in overcoming established barriers to cancer pain care. A pain self-management resource was developed to include: (1) a template for setting specific, measureable, achievable, relevant and time-bound goals of care, as well as identifying potential obstacles and ways to overcome these; and (2) a pain management plan detailing exacerbating and alleviating factors, current strategies for management, and contacts for support.
Significance of results
Self-management resources have the potential for addressing barriers not only at the patient level, but also at provider and health system levels. A cluster randomized controlled trial is under way to test effectiveness of the resource designed in this project in combination with pain screening, audit and feedback, and provider education. More research of this kind is needed to understand how interventions at different levels can be optimally combined to overcome barriers and improve care.
Natural living conductive biofilms transport electrons between electrodes and cells, as well as among cells fixed within the film, catalyzing an array of reactions from acetate oxidation to CO2 reduction. Synthetic biology offers tools to modify or improve electron transport through biofilms, creating a new class of engineered living conductive materials. Engineered living conductive materials could be used in a range of applications for which traditional conducting polymers are not appropriate, including improved catalytic coatings for microbial fuel-cell electrodes, self-powered sensors for austere environments, and next-generation living components of bioelectronic devices that interact with the human microbiome.
The penetration depth of 1-12 keV electrons in most materials is less than one micron and the characteristic soft x-rays that are produced can be used to identify the elements present in the surface. Varying the energy of the incident electron beam enables the depth of analysis to be controlled.
Soft x-rays often exhibit large 'chemical effects' (changes in peak profile and peak position) which can he correlated with chemical changes. A study of such effects for each element present in the sample surface, as a function of electron-beam energy, can in some cases, permit changes in the chemical state (valency - coordination number-spin state etc.) to be determined as a function of depth.
Such analyses can be carried out either in a conventional x-ray spectrometer in which the x-ray tube has been replaced by a gas-discharge source, or in a spectrometer in which the sample is bombarded with electrons from a normal electron gun. In this paper these techniques are outlined and some applications reviewed:- the analysis of oxide layers on aluminium and steel, the analysis of aluminium-nitride layers produced by MOCVD on gallium arsenide, the analysis of silica fiims (with added boron and phosphorus oxides) on silicon and the analysis of zinc-oxide films on glass.
The characterization of defect configurations in various perovskite-like substrate materials for high Tc superconductor epitaxial films has been conducted using white beam synchrotron X-ray topography. The substrates were found to contain crystal lattice defects such as twins, dislocations and grain boundaries. It is shown that characterization of substrates can potentially afford insight into factors controlling the properties of the high Tc superconductor tilms supported on them. This can help in the selection of optimum substrate material. Defect formation mechanisms in individual materials as well as their respective influences on the films are discussed. Comparisons between the physical and chemical properties of several potential substrate materials are presented.
Y.Ba2Cu3O7, a high TC superconductor powder, was shock compacted and explosively welded inside a copper matrix using the explosive fabrication methods described by Murr, Hare and Eror. The shock compression fabrication technique provides the ability to process the superconductor powders into useable structures that will minimize environmental degradation and will not negatively affect the physical or mechanical properties. Additionally, the introduction of shock induced defects are known to increase solid-state reactivity in ceramic materials. For this reason, shock compression fabrication of the superconductor/copper system offers the possibility of enhancing the superconducting properties of the YBa2Cu3O7 powders.
OBJECTIVES/SPECIFIC AIMS: In the first aim, we will evaluate the proportion of highly HIV-susceptible memory CD4+ T cells present in the rectal mucosa, based on the proliferation status and expression of the HIV susceptibility markers, CCR5 and α4β7, between HIV-negative adolescent MSM and adult MSM engaging in RAI. The second aim will assess differences between the two study groups in the ratio of Th17 cells (CD4+ IL17+) to Treg cells (CD4+ FoxP3+ CD25+) in the rectal mucosa as a determinant of mucosal inflammation. Finally, in the third aim, we will utilize ex vivo rectal biopsy explant challenge experiments to examine whether HIV target cell availability and the Th17/Treg ratio influence rectal mucosal HIV susceptibility. METHODS/STUDY POPULATION: Rectal biopsy specimens are being collected from healthy, HIV-negative men that comprise the two study groups: 40 adolescent MSM 18-21 years of age who have engaged in RAI at least once previously in their lifetime and 40 adult MSM ≥35 years of age who have engaged in RAI for the previous 5 consecutive years with a minimum of 12 episodes annually. To identify CD4+ subsets of interest for aims 1 and 2, rectal mucosal mononuclear cells are isolated and phenotyped with CD45, CD3, CD4, CD45RA, CCR7, CD69, CCR5, α4β7, Ki67, FOXP3, and CD25 antibodies. To identify the Th17 cell subtype, the cells are stimulated with PMA/Ionamycin and stained with an antibody specific to IL-17A. Using cross-sectional analyses, we will compare the frequencies of mucosal CD4+ T cells that express certain phenotypic characteristics and evaluate differences in the Th17/Treg ratio between adolescent and adult MSM. For aim 3, rectal biopsy specimens are inoculated with HIV virus and the culture supernatant is assayed for p24 concentration on days 3, 7, 10 14, and 18. Longitudinal analyses will be performed to detect differences in p24 concentration at each time point and assess associations with mucosal target cell availability and with the Th17/Treg ratio. RESULTS/ANTICIPATED RESULTS: We hypothesize that younger age will be associated with enhanced memory CD4+ T cell proliferation and increased expression of HIV susceptibility markers (CCR5 and/or α4β7). In addition, we expect that the rectal mucosa of adolescent MSM will demonstrate a higher Th17/Treg ratio as compared to adult MSM, which could facilitate HIV transmission. It is also anticipated that rectal mucosal immune phenotypes characterized by increased HIV target cell availability and high Th17/Treg ratios will be associated with enhanced mucosal HIV susceptibility in the explant challenge model. DISCUSSION/SIGNIFICANCE OF IMPACT: There is a paucity of information regarding the mechanisms of rectal HIV transmission, and no studies to date investigate the immunologic effects of aging on transmission in the rectal mucosa. The results from this study will provide important information regarding age-related differences in the immune cell composition of the rectal mucosa as a critical step in better understanding immunologic factors that influence rectal HIV transmission.
OBJECTIVES/SPECIFIC AIMS: The purpose of this study was to summarize the existing literature on clinical research competencies and determine what competency assessments currently exist. We also wished to assess which competencies should be included in a research competency assessment tool and to evaluate the validity of current competency assessments. We also examined whether these competency assessments can be used for the purposes of formative and summative evaluation. METHODS/STUDY POPULATION: Prior to conducting our search of the literature, we first compiled a list of search terms (e.g., clinical, research, training, competencies) that could be used to locate articles. We then entered these search terms, in various combinations, on several relevant databases. We evaluated abstracts of the articles revealed by this search to determine whether they met three criteria. The first criterion was that the subjects of the article must be clinical investigators or clinical investigators in training. Relevant disciplines included medicine, public health, nursing, pharmacy, dentistry, and other related fields. The second criterion was that articles should focus on research-based (as opposed to clinical) skills. The last criterion was that research-based competencies (or related terms like skills, abilities, mastery, knowledge) must be assessed in some way. If the abstract suggested that the article met all three criteria, the full article was retrieved and analyzed in-depth. To identify articles that eluded literature search, we then examined the reference section of these articles and examined articles that cited these articles. When no additional articles could be located, the search for articles stopped. Once a pool of potentially eligible articles was identified, the articles underwent peer review by several researchers experienced with clinical research and competency-based education and assessment. Articles that were unanimously judged to meet the criteria were included in the systematic review. RESULTS/ANTICIPATED RESULTS: Approximately 75 articles were selected and reviewed for eligibility. After peer review, we found that only a small fraction of these articles met our criteria for inclusion in the systematic literature review. Our preliminary findings suggest that there are few assessments of clinical research competency and that many of these assessments are poorly validated. DISCUSSION/SIGNIFICANCE OF IMPACT: The findings of the present study suggest that the validation methods used thus far are limited and so the validity of many of these assessments is effectively unproven. Future research on assessments of clinical research competency ought to address these limitations by sampling clinical researchers, using more rigorous validation methods, and by confirming hypothesized factor structures in new samples. The use of better-validated instruments may enhance measurement of trainees’ knowledge and skill levels for the purposes of formative and summative assessment.
Flexible piezoelectric generators (PEGs) present a unique opportunity for renewable and sustainable energy harvesting. Here, we present a low-temperature and low-energy deposition method using solvent evaporation-assisted three-dimensional printing to deposit electroactive poly(vinylidene fluoride) (PVDF)-trifluoroethylene (TrFE) up to 19 structured layers. Visible-wavelength transmittance was above 92%, while ATR-FTIR spectroscopy showed little change in the electroactive phase fraction between layer depositions. Electroactivity from the fabricated PVDF-TrFE PEGs showed that a single structured layer gave the greatest output at 289.3 mV peak-to-peak voltage. This was proposed to be due to shear-induced polarization affording the alignment of the fluoropolymer dipoles without an electric field or high temperature.
Formation of a low barrier back contact plays a critical role in improving the photoconversion efficiency of the CdTe solar cells. Incorporating a buffer layer to minimize the band bending at the back of the CdTe device can significantly lower the barrier for the hole current, improving open circuit voltage (VOC) and the fill factor. Over the past years, researchers have incorporated the both ZnTe and Te as buffer layers to improve CdTe device performance. Here we compare device performance using these two materials as buffer layers at the back of CdTe devices. We show that using Te in contact to CdTe results in higher performance than using ZnTe in contact to the CdTe. Low temperature current density-voltage measurements show that Te results is a lower barrier with CdTe than ZnTe, indicating that Te has better band alignment, resulting in less downward bending in the CdTe at the back interface, than ZnTe does.
During the past two decades, it has been amply documented that neuropsychiatric disorders (NPDs) disproportionately account for burden of illness attributable to chronic non-communicable medical disorders globally. It is also likely that human capital costs attributable to NPDs will disproportionately increase as a consequence of population aging and beneficial risk factor modification of other common and chronic medical disorders (e.g., cardiovascular disease). Notwithstanding the availability of multiple modalities of antidepressant treatment, relatively few studies in psychiatry have primarily sought to determine whether improving cognitive function in MDD improves patient reported outcomes (PROs) and/or is cost effective. The mediational relevance of cognition in MDD potentially extrapolates to all NPDs, indicating that screening for, measuring, preventing, and treating cognitive deficits in psychiatry is not only a primary therapeutic target, but also should be conceptualized as a transdiagnostic domain to be considered regardless of patient age and/or differential diagnosis.
The preconception, pregnancy and immediate postpartum and newborn periods are times for mothers and their offspring when they are especially vulnerable to major stressors – those that are sudden and unexpected and those that are chronic. Their adverse effects can transcend generations. Stressors can include natural disasters or political stressors such as conflict and/or migration. Considerable evidence has accumulated demonstrating the adverse effects of natural disasters on pregnancy outcomes and developmental trajectories. However, beyond tracking outcomes, the time has arrived for gathering more information related to identifying mechanisms, predicting risk and developing stress-reducing and resilience-building interventions to improve outcomes. Further, we need to learn how to encapsulate both the quantitative and qualitative information available and share it with communities and authorities to mitigate the adverse developmental effects of future disasters, conflicts and migrations. This article briefly reviews prenatal maternal stress and identifies three contemporary situations (wildfire in Fort McMurray, Alberta, Canada; hurricane Harvey in Houston, USA and transgenerational and migrant stress in Pforzheim, Germany) where current studies are being established by Canadian investigators to test an intervention. The experiences from these efforts are related along with attempts to involve communities in the studies and share the new knowledge to plan for future disasters or tragedies.
The aim of this study was to describe patient level costing methods and develop a database of healthcare resource use and cost in patients with AHF receiving ventricular assist device (VAD) therapy.
Patient level micro-costing was used to identify documented activity in the years preceding and following VAD implantation, and preceding heart transplant for a cohort of seventy-seven consecutive patients listed for heart transplantation (2009–12). Clinician interviews verified activity, established time resource required for each activity, and added additional undocumented activities. Costs were sourced from the general ledger, salary, stock price, pharmacy formulary data, and from national medical benefits and prostheses lists. Linked administrative data analyses of activity external to the implanting institution, used National Weighted Activity Units (NWAU), 2014 efficient price, and admission complexity cost weights and were compared with micro-costed data for the implanting admission.
The database produced includes patient level activity and costs associated with the seventy-seven patients across thirteen resource areas including hospital activity external to the implanting center. The median cost of the implanting admission using linked administrative data was $246,839 (interquartile range [IQR] $246,839–$271,743), versus $270,716 (IQR $211,740–$378,482) for the institutional micro-costing (p = .08).
Linked administrative data provides a useful alternative for imputing costs external to the implanting center, and combined with institutional data can illuminate both the pathways to transplant referral and the hospital activity generated by patients experiencing the terminal phases of heart failure in the year before transplant, cf-VAD implant, or death.
We test the hypothesis that low-visibility shocks to text-based network industry peers can explain industry momentum. We consider industry peer firms identified through 10-K product text and focus on economic peer links that do not share common Standard Industrial Classification (SIC) codes. Shocks to less visible peers generate economically large momentum profits and are stronger than own-firm momentum variables. More visible traditional SIC-based peers generate only small, short-lived momentum profits. Our findings are consistent with momentum profits arising partially from inattention to economic links of less visible industry peers.
Social support networks for older persons have been related to health outcomes including differences in psychological wellbeing (PWB). However, the specifics of this relationship remain unclear especially in sub-Saharan Africa. This study investigates the (1) relationship between aspects of social support and PWB among older persons in Ghana and (2) the extent to which this relationship is moderated by their education levels and locational characteristics.
The study included 1,200 community-residing individuals aged 50 years and older who participated in an Aging, Health, Psychological Wellbeing and Health-seeking Behavior Study (AHPWHB) conducted between July 2016 and February 2017. Logistic regression models evaluated the associations of social support and their interactions with education and locational variables in PWB.
Several aspects of meaningful social support: family/friends contacts ( β = 0.958, p < 0.05), couple focused ( β = 0.887, p < 0.001), emotional bonds ( β = 0.658, p < 0.005), attending social events ( β = 0.519, p < 0.001) and remittances from children ( β = 0.394, p < 0.005) significantly related to improved PWB in later life. These associations remained robust and largely strengthened after accounting for respondents’ background and health-related factors. Education and locational characteristics substantially influenced the associations between social support and PWB.
These findings suggest that especially in terms of PWB, aspects of meaningful social support networks are critical elements in later life. Strengthening opportunities for closer interpersonal relations with older persons may enhance their mental health, quality of life and independence.