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Understanding the distribution and extent of suitable habitats is critical for the conservation of endangered and endemic taxa. Such knowledge is limited for many Central African species, including the rare and globally threatened Grey-necked Picathartes Picathartes oreas, one of only two species in the family Picathartidae endemic to the forests of Central Africa. Despite growing concerns about land-use change resulting in fragmentation and loss of forest cover in the region, neither the extent of suitable habitat nor the potential species’ distribution is well known. We combine 339 (new and historical) occurrence records of Grey-necked Picathartes with environmental variables to model the potential global distribution. We used a Maximum Entropy modelling approach that accounted for sampling bias. Our model suggests that Grey-necked Picathartes distribution is strongly associated with steeper slopes and high levels of forest cover, while bioclimatic, vegetation health, and habitat condition variables were all excluded from the final model. We predicted 17,327 km2 of suitable habitat for the species, of which only 2,490 km2 (14.4%) are within protected areas where conservation designations are strictly enforced. These findings show a smaller global distribution of predicted suitable habitat forthe Grey-necked Picathartes than previously thought. This work provides evidence to inform a revision of the International Union for Conservation of Nature (IUCN) Red List status, and may warrant upgrading the status of the species from “Near Threatened” to “Vulnerable”.
Variation in delineation of target volumes/organs at risk (OARs) is well recognised in radiotherapy and may be reduced by several methods including teaching. We evaluated the impact of teaching on contouring variation for thoracic/pelvic stereotactic ablative radiotherapy (SABR) during a virtual contouring workshop.
Materials and methods:
Target volume/OAR contours produced by workshop participants for three cases were evaluated against reference contours using DICE similarity coefficient (DSC) and line domain error (LDE) metrics. Pre- and post-workshop DSC results were compared using Wilcoxon signed ranks test to determine the impact of teaching during the workshop.
Of 50 workshop participants, paired pre- and post-workshop contours were available for 21 (42%), 20 (40%) and 22 (44%) participants for primary lung cancer, pelvic bone metastasis and pelvic node metastasis cases, respectively. Statistically significant improvements post-workshop in median DSC and LDE results were observed for 6 (50%) and 7 (58%) of 12 structures, respectively, although the magnitude of DSC/LDE improvement was modest in most cases. An increase in median DSC post-workshop ≥0·05 was only observed for GTVbone, IGTVlung and SacralPlex, and reduction in median LDE > 1 mm was only observed for GTVbone, CTVbone and SacralPlex. Post-workshop, median DSC values were >0·7 for 75% of structures. For 92% of the structures, post-workshop contours were considered to be acceptable or within acceptable variation following review by the workshop faculty.
This study has demonstrated that virtual SABR contouring training is feasible and was associated with some improvements in contouring variation for multiple target volumes/OARs.
Climate change is a key problem of the 21st century. China, as the largest emitter of greenhouse gases, has committed to stabilize its current emissions and dramatically increase the share of electricity production from non-fossil fuels by 2030. However, this is only a first step: in the longer term, China needs to aggressively strive to reach a goal of zero-emissions. Through detailed discussions of electricity pricing, electric vehicle policies, nuclear energy policies, and renewable energy policies, this book reviews how near-term climate and energy policies can affect long-term decarbonization pathways beyond 2030, building the foundations for decarbonization in advance of its realization. Focusing primarily on the electricity sector in China - the main battleground for decarbonization over the next century – it provides a valuable resource for researchers and policymakers, as well as energy and climate experts.
Regionalizing pre-colonial Africa aids in the collection and interpretation of primary sources as data for further analysis. This article includes a map with six broad regions and 34 sub-regions, which form a controlled vocabulary within which researchers may geographically organize and classify disparate pieces of information related to Africa’s past. In computational terms, the proposed African regions serve as data containers in order to consolidate, link, and disseminate research among a growing trend in digital humanities projects related to the history of the African diasporas before c. 1900. Our naming of regions aims to avoid terminologies derived from European slave traders, colonialism, and modern-day countries.
We evaluated the risk of patients contracting coronavirus disease 2019 (COVID-19) during their hospital stay to inform the safety of hospitalization for a non–COVID-19 indication during this pandemic.
A case series of adult patients hospitalized for 2 or more nights from May 15 to June 15, 2020 at large tertiary-care hospital in the midwestern United States was reviewed. All patients were screened at admission with the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) polymerase chain reaction (PCR) test. Selected adult patients were also tested by IgG serology. After dismissal, patients with negative serology and PCR at admission were asked to undergo repeat serologic testing at 14–21 days after discharge. The primary outcome was healthcare-associated COVID-19 defined as a new positive SARS-CoV-2 PCR test on or after day 4 of hospital stay or within 7 days of hospital dismissal, or seroconversion in patients previously established as seronegative.
Of the 2,068 eligible adult patients, 1,778 (86.0%) completed admission PCR testing, while 1,339 (64.7%) also completed admission serology testing. Of the 1,310 (97.8%) who were both PCR and seronegative, 445 (34.0%) repeated postdischarge serology testing. No healthcare-associated COVID-19 cases were detected during the study period. Of 1,310 eligible PCR and seronegative adults, no patients tested PCR positive during hospital admission (95% confidence interval [CI], 0.0%–0.3%). Of the 445 (34.0%) who completed postdischarge serology testing, no patients seroconverted (0.0%; 95% CI, 0.0%–0.9%).
We found low likelihood of hospital-associated COVID-19 with strict adherence to universal masking, physical distancing, and hand hygiene along with limited visitors and screening of admissions with PCR.
ABSTRACT IMPACT: Through conducting this systematic review and meta-analysis, we will elucidate which factors influence thoracic aortic aneurysm growth, which will further help clinicians to properly stratify and manage their patients with TAAs. OBJECTIVES/GOALS: Thoracic aortic aneurysms (TAA) are an indolent but fatal disease, and the patient characteristics that predict both overall growth and growth rate are still not well characterized. Our goal is to conduct a systematic review and meta-analysis in other to better describe different patient characteristics that predict TAA growth. METHODS/STUDY POPULATION: M.M. conducted a search of Ovid MEDLINE, Embase, and Scopus to identify articles. Inclusion criteria were any longitudinal study reporting asymptomatic TAA growth, growth rates, or clinical proxies for growth such as dissection, rupture, emergency surgery, and death. M.H and P.B. independently applied the criteria to the results of the search. Conflicts were resolved by N.B. Data was extracted and risk of bias assessed independently by M.H. and P.B. Summary estimates of the outcome variables are combined across studies using standard meta-analysis methods. Heterogeneity is assessed via forest plots, chi2 test (Q test), and I2 statistic. Sensitivity analysis is conducted to assess robustness of the findings. RESULTS/ANTICIPATED RESULTS: The literature search resulted in 3,419 abstracts, of which 176 were included and thus require a full text review. Cohen’s Kappa coefficient was 0.64, indicating substantial agreement and high inter-rater reliability. We describe four categories of patient characteristics influencing the growth of asymptomatic TAAs: demographics, genetic or inheritable conditions, hemodynamic or biomechanical factors, and serum biomarkers. We describe the measure of effect for all variables. We anticipate there is a significant level of heterogeneity between studies, and potentially moderate risk of bias for many of the included studies as they are retrospective and observational in nature. Furthermore, we anticipate publication bias and evaluate it with funnel plots. DISCUSSION/SIGNIFICANCE OF FINDINGS: Understanding the factors that influence the growth of asymptomatic thoracic aortic aneurysms (TAA) is paramount, as the size and growth rate of TAAs dictates the clinical course. Little is understood about the degree to which different characteristics influence growth. This meta-analysis will help elucidate factors that promote TAA growth.
ABSTRACT IMPACT: This work examines the association between diabetes mellitus and latent tuberculosis infection among a cohort of household contacts exposed to active tuberculosis in Ethiopia, focusing attention on the need for further translational research to determine the mechanisms of susceptibility to Mycobacterium tuberculosis infection among individuals with diabetes and pre-diabetes. OBJECTIVES/GOALS: Diabetes mellitus (DM) is an established risk factor for active TB disease, but there is limited understanding of the relationship of DM and latent tuberculosis (LTBI). We sought to determine the relationship between DM or pre-DM with LTBI among household or close contacts (HHCs) of active TB cases in Ethiopia. METHODS/STUDY POPULATION: We conducted a cross-sectional study of the HHCs of index active TB cases enrolled in an ongoing TB Research Unit (TBRU) study in Addis Ababa, Ethiopia. HHCs of individuals with laboratory-confirmed TB had QuantiFERON ®-TB Gold Plus (QFT) and glycated hemoglobin (HbA1c) tests performed. LTBI was defined as a positive QFT and lack of symptoms. HbA1C results were used to define no DM (HbA1c <5.7), pre-DM (HbA1c 5.7-6.5%), and DM (HbA1c >6.5% or prior history of diabetes). Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI) after adjustment for age, sex and HIV status as potential confounders. RESULTS/ANTICIPATED RESULTS: Among 466 HHCs, the median age was 29 years (IQR 23-38), 58.8% were female, 3.4% were HIV-positive, and median BMI was 20.9 kg/m^2 (IQR 18.9-23.8). Overall, 329 HHCs (70.6%) had LTBI, 26 (5.6%) had DM and 73 (15.7%) had pre-DM. Compared to HHC without DM, the prevalence of LTBI was higher in those with pre-DM (68.9% vs. 72.6%; OR 1.19, 95% CI 0.69-2.13) and those with DM (88.5%; OR 3.45, 95% CI 1.17-14.77). In multivariable analysis, there was a trend towards increased LTBI risk among HHCs with DM vs. without DM (OR 2.16, 95% CI 0.67-9.70) but the difference was not statistically significant. Among HHCs with LTBI, the median IFN-? response to TB1 antigen was modestly greater in those with DM (5.3 IU/mL; IQR 3.0-7.8) and pre-DM (5.4 IU/mL; IQR 2.0-8.4) compared to HHCs without DM (4.3 IU/mL; IQR 1.4-7.7). DISCUSSION/SIGNIFICANCE OF FINDINGS: Our results suggest that DM may increase the risk of LTBI among HHCs recently exposed to active TB. Among those with LTBI, increased IFN-? antigen response in the presence of DM and pre-DM may indicate an exaggerated but ineffectual response to TB. Further investigation is needed to assess how dysglycemia impacts susceptibility to M. tuberculosis.
We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band (
), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
In recent years, an increasing number of online archival databases of primary sources related to the history of the African diaspora and slavery have become freely and readily accessible for scholarly and public consumption. This proliferation of digital projects and databases presents a number of challenges related to aggregating data geographically according to the movement of people in and out of Africa across time and space. As a requirement to linking data of open-source digital projects, it has become necessary to delimit the entire continent of precolonial Africa during the era of the slave trade into broad regions and sub-regions that can allow the grouping of data effectively and meaningfully.
Patients with Parkinson’s disease psychosis (PDP) are often treated with an atypical antipsychotic, especially quetiapine or clozapine, but side effects, lack of sufficient efficacy, or both may motivate a switch to pimavanserin, the first medication approved for management of PDP. How best to implement a switch to pimavanserin has not been clear, as there are no controlled trials or case series in the literature to provide guidance. An abrupt switch may interrupt partially effective treatment or potentially trigger rebound effects from antipsychotic withdrawal, whereas cross-taper involves potential drug interactions. A panel of experts drew from published data, their experience treating PDP, lessons from switching antipsychotic drugs in other populations, and the pharmacology of the relevant drugs, to establish consensus recommendations. The panel concluded that patients with PDP can be safely and effectively switched from atypical antipsychotics used off label in PDP to the recently approved pimavanserin by considering each agent’s pharmacokinetics and pharmacodynamics, receptor interactions, and the clinical reason for switching (efficacy or adverse events). Final recommendations are that such a switch should aim to maintain adequate 5-HT2A antagonism during the switch, thus providing a stable transition so that efficacy is maintained. Specifically, the consensus recommendation is to add pimavanserin at the full recommended daily dose (34 mg) for 2–6 weeks in most patients before beginning to taper and discontinue quetiapine or clozapine over several days to weeks. Further details are provided for this recommendation, as well as for special clinical circumstances where switching may need to proceed more rapidly.