518 research outputs found
Jihadist Web Postings and Popular Social Media: A Forensic Psychological Analysis
The development of the Internet has made it easy for individuals to communicate with others around the world, especially with the increased ease of social media. The Internet is used for interpersonal communication such as social media, meeting new people in chat rooms, joining interest distribution lists, among others leisure activities (Lennings, Amon, Brummert, & Lennings, 2010). According to Pew Research (2014), 74% of adults, with 89% of individuals ages 18-29 using social media extensively. This statistic is particularly important as it is estimated approximately 70% of the individuals recruited to engage in terrorism are ages 18 to 23 (Lennings et al., 2010)
Lessons Learned from the Implementation of a Medically Enhanced Residential Treatment (Mert) Model Integrating Intravenous Antibiotics and Residential Addiction Treatment
BACKGROUND: Hospitalizations for severe infections associated with substance use disorder (SUD) are increasing. People with SUD often remain hospitalized for many weeks instead of completing intravenous antibiotics at home; often, they are denied skilled nursing facility admission. Residential SUD treatment facilities are not equipped to administer intravenous antibiotics. We developed a medically enhanced residential treatment (MERT) model integrating residential SUD treatment and long-term IV antibiotics as part of a broader hospital-based addiction medicine service. MERT had low recruitment and retention, and ended after six months. The goal of this study was to describe the feasibility and acceptability of MERT, to understand implementation factors, and explore lessons learned.
METHODS: We conducted a mixed-methods evaluation. We included all potentially eligible MERT patients, defined by those needing ā„2 weeks of intravenous antibiotics discharged from February 1 to August 1, 2016. We used chart review to identify diagnoses, antibiotic treatment location, and number of recommended and actual IV antibiotic-days completed. We audiorecorded and transcribed key informant interviews with patients and staff. We conducted an ethnographic analysis of interview transcripts and implementation field notes.
RESULTS: Of the 45 patients needing long-term intravenous antibiotics, 18 were ineligible and 20 declined MERT. 7 enrolled in MERT and three completed their recommended intravenous antibiotic course. MERT recruitment barriers included patient ambivalence towards residential treatment, wanting to prioritize physical health needs, and fears of untreated pain in residential. MERT retention barriers included high demands of residential treatment, restrictive practices due to PICC lines, and perceptions by staff and other residents that MERT patients āstood outā as ādifferent.ā Despite the challenges, key informants felt MERT was a positive construct.
CONCLUSIONS: Though MERT had many possible advantages; it proved more challenging to implement than anticipated. Our lessons may be applicable to future models integrating posthospital intravenous antibiotics and SUD care
Phytoplankton blooms weakly influence the cloud forming ability of sea spray aerosol
After many field studies, the establishment of connections between marine microbiological processes, sea spray aerosol (SSA) composition, and cloud condensation nuclei (CCN) has remained an elusive challenge. In this study, we induced algae blooms to probe how complex changes in seawater composition impact the ability of nascent SSA to act as CCN, quantified by using the apparent hygroscopicity parameter (Īŗapp). Throughout all blooms, Īŗapp ranged between 0.7 and 1.4 (average 0.95āĀ±ā0.15), consistent with laboratory investigations using algaeāproduced organic matter, but differing from climate model parameterizations and in situ SSA generation studies. The size distribution of nascent SSA dictates that changes in Īŗapp associated with biological processing induce less than 3% change in expected CCN concentrations for typical marine cloud supersaturations. The insignificant effect of hygroscopicity on CCN concentrations suggests that the SSA production flux and/or secondary aerosol chemistry may be more important factors linking ocean biogeochemistry and marine clouds.Key PointsChanges in seawater and sea spray composition did not strongly affect expected CCN concentrationsBlooms may impact clouds more strongly through changes in aerosol flux or secondary chemistryModel parameterizations likely overestimate changes in cloud nuclei due to primary marine organicsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134444/1/grl54978_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134444/2/grl54978-sup-0001-supinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134444/3/grl54978.pd
What are the impacts of within-field farmland management practices on the flux of greenhouse gases from arable cropland in temperate regions? A systematic map protocol
Background: Reducing greenhouse gas emissions is a vital step in limiting climate change and meeting the goals outlined in the COP 21 Paris Agreement of 2015. Studies have suggested that agriculture accounts for around 11% of total greenhouse gas emissions and the industry has a significant role in meeting international and national climate change reduction objectives. However, there is currently little consensus on the mechanisms that regulate the production and assimilation of greenhouse gases in arable land and the practical factors that affect the process. Practical advice for farmers is often overly general, and models based on the amount of nitrogen fertiliser applied, for example, are used despite a lack of knowledge of how local conditions affect the process, such as the importance of humus content and soil types. Here, we propose a systematic map of the evidence relating to the impact on greenhouse gas flux from the agricultural management of arable land in temperate regions. Methods: Using established methods for systematic mapping in environmental sciences we will search for, collate and catalogue research studies relating to the impacts of farming in temperate systems on greenhouse gas emissions. We will search 6 bibliographic databases using a tested search string, and will hand search a web-based search engine and a list of organisational web sites. Furthermore, evidence will be sought from key stakeholders. Search results will then be screened for relevance at title, abstract and full text levels according to a predefined set of eligibility criteria. Consistency checking will be employed to ensure the criteria are being applied accurately and consistently. Relevant studies will then be subjected to coding and meta-data extraction, which will be used to populate a systematic map database describing each relevant study's settings, methods and measured outcomes. The mapping process will help to identify knowledge gaps (subjects lacking in evidence warranting further primary research) and knowledge clusters (subjects with sufficient studies to allow a useful full systematic review), and will highlight best and suboptimal research methods
The role of taxonomic expertise in interpretation of metabarcoding studies
Abstract
The performance of DNA metabarcoding approaches for characterizing biodiversity can be influenced by multiple factors. Here, we used morphological assessment of taxa in zooplankton samples to develop a large barcode database and to assess the congruence of taxonomic identification with metabarcoding under different conditions. We analysed taxonomic assignment of metabarcoded samples using two genetic markers (COI, 18S V1ā2), two types of clustering into molecular operational taxonomic units (OTUs, ZOTUs), and three methods for taxonomic assignment (RDP Classifier, BLASTn to GenBank, BLASTn to a local barcode database). The local database includes 1042 COI and 1108 18S (SSU) barcode sequences, and we added new high-quality sequences to GenBank for both markers, including 109 contributions at the species level. The number of phyla detected and the number of taxa identified to phylum varied between a genetic marker and among the three methods used for taxonomic assignments. Blasting the metabarcodes to the local database generated multiple unique contributions to identify OTUs and ZOTUs. We argue that a multi-marker approach combined with taxonomic expertise to develop a curated, vouchered, local barcode database increases taxon detection with metabarcoding, and its potential as a tool for zooplankton biodiversity surveys
Utility of Multi-Parametric Quantitative Magnetic Resonance Imaging for Characterization and Radiotherapy Response Assessment in Soft-Tissue Sarcomas and Correlation With Histopathology
Purpose: To evaluate repeatability of quantitative multi-parametric MRI in retroperitoneal sarcomas, assess parameter changes with radiotherapy, and correlate pre-operative values with histopathological findings in the surgical specimens.Materials and Methods: Thirty patients with retroperitoneal sarcoma were imaged at baseline, of whom 27 also underwent a second baseline examination for repeatability assessment. 14/30 patients were treated with pre-operative radiotherapy and were imaged again after completing radiotherapy (50.4 Gy in 28 daily fractions, over 5.5 weeks). The following parameter estimates were assessed in the whole tumor volume at baseline and following radiotherapy: apparent diffusion coefficient (ADC), parameters of the intra-voxel incoherent motion model of diffusion-weighted MRI (D, f, D*), transverse relaxation rate, fat fraction, and enhancing fraction after gadolinium-based contrast injection. Correlation was evaluated between pre-operative quantitative parameters and histopathological assessments of cellularity and fat fraction in post-surgical specimens (ClinicalTrials.gov, registration number NCT01902667).Results: Upper and lower 95% limits of agreement were 7.1 and ā6.6%, respectively for median ADC at baseline. Median ADC increased significantly post-radiotherapy. Pre-operative ADC and D were negatively correlated with cellularity (r = ā0.42, p = 0.01, 95% confidence interval (CI) ā0.22 to ā0.59 for ADC; r = ā0.45, p = 0.005, 95% CI ā0.25 to ā0.62 for D), and fat fraction from Dixon MRI showed strong correlation with histopathological assessment of fat fraction (r = 0.79, p = 10ā7, 95% CI 0.69ā0.86).Conclusion: Fat fraction on MRI corresponded to fat content on histology and therefore contributes to lesion characterization. Measurement repeatability was excellent for ADC; this parameter increased significantly post-radiotherapy even in disease categorized as stable by size criteria, and corresponded to cellularity on histology. ADC can be utilized for characterizing and assessing response in heterogeneous retroperitoneal sarcomas
Direct involvement of the TEN domain at the active site of human telomerase
Telomerase is a ribonucleoprotein that adds DNA to the ends of chromosomes. The catalytic protein subunit of telomerase (TERT) contains an N-terminal domain (TEN) that is important for activity and processivity. Here we describe a mutation in the TEN domain of human TERT that results in a greatly increased primer Kd, supporting a role for the TEN domain in DNA affinity. Measurement of enzyme kinetic parameters has revealed that this mutant enzyme is also defective in dNTP polymerization, particularly while copying position 51 of the RNA template. The catalytic defect is independent of the presence of binding interactions at the 5ā²-region of the DNA primer, and is not a defect in translocation rate. These data suggest that the TEN domain is involved in conformational changes required to position the 3ā²-end of the primer in the active site during nucleotide addition, a function which is distinct from the role of the TEN domain in providing DNA binding affinity
Clinically Actionable Hypercholesterolemia and Hypertriglyceridemia in Children with Nonalcoholic Fatty Liver Disease
OBJECTIVE:
To determine the percentage of children with nonalcoholic fatty liver disease (NAFLD) in whom intervention for low-density lipoprotein cholesterol or triglycerides was indicated based on National Heart, Lung, and Blood Institute guidelines.
STUDY DESIGN:
This multicenter, longitudinal cohort study included children with NAFLD enrolled in the National Institute of Diabetes and Digestive and Kidney Diseases Nonalcoholic Steatohepatitis Clinical Research Network. Fasting lipid profiles were obtained at diagnosis. Standardized dietary recommendations were provided. After 1 year, lipid profiles were repeated and interpreted according to National Heart, Lung, and Blood Institute Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction. Main outcomes were meeting criteria for clinically actionable dyslipidemia at baseline, and either achieving lipid goal at follow-up or meeting criteria for ongoing intervention.
RESULTS:
There were 585 participants, with a mean age of 12.8 years. The prevalence of children warranting intervention for low-density lipoprotein cholesterol at baseline was 14%. After 1 year of recommended dietary changes, 51% achieved goal low-density lipoprotein cholesterol, 27% qualified for enhanced dietary and lifestyle modifications, and 22% met criteria for pharmacologic intervention. Elevated triglycerides were more prevalent, with 51% meeting criteria for intervention. At 1 year, 25% achieved goal triglycerides with diet and lifestyle changes, 38% met criteria for advanced dietary modifications, and 37% qualified for antihyperlipidemic medications.
CONCLUSIONS:
More than one-half of children with NAFLD met intervention thresholds for dyslipidemia. Based on the burden of clinically relevant dyslipidemia, lipid screening in children with NAFLD is warranted. Clinicians caring for children with NAFLD should be familiar with lipid management
The Impact of Enhanced Halo Resolution on the Simulated Circumgalactic Medium
Traditional cosmological hydrodynamics simulations fail to spatially resolve
the circumgalatic medium (CGM), the reservoir of tenuous gas surrounding a
galaxy and extending to its virial radius. We introduce the technique of
Enhanced Halo Resolution (EHR), enabling more realistic physical modeling of
the simulated CGM by consistently forcing gas refinement to smaller scales
throughout the virial halo of a simulated galaxy. We investigate the effects of
EHR in the Tempest simulations, a suite of Enzo-based cosmological zoom
simulations following the evolution of an L* galaxy, resolving spatial scales
of 500 comoving pc out to 100 comoving kpc in galactocentric radius. Among its
many effects, EHR (1) changes the thermal balance of the CGM, increasing its
cool gas content and decreasing its warm/hot gas content; (2) preserves cool
gas structures for longer periods; and (3) enables these cool clouds to exist
at progressively smaller size scales. Observationally, this results in a boost
in "low ions" like H I and a drop in "high ions" like O VI throughout the CGM.
These effects of EHR do not converge in the Tempest simulations, but
extrapolating these trends suggests that the CGM in reality is a mist
consisting of ubiquitous, small, long-lived, cool clouds suspended in a hot
medium at the virial temperature of the halo. Additionally, we explore the
physical mechanisms to explain why EHR produces the above effects, proposing
that it works both by (1) better sampling the distribution of CGM phases
enabling runaway cooling in the denser, cooler tail of the phase distribution;
and (2) preventing cool gas clouds from artificially mixing with the ambient
hot halo and evaporating. Evidence is found for both EHR mechanisms occurring
in the Tempest simulations.Comment: 19 pages, 13 figures, submitted to ApJ. Simulation movies available
at http://chummels.org/tempes
Wildfire Risk as a Socioecological Pathology
Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological āpathologyā: that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for these interactions in terms of socioecological systems, also known as coupled natural and human systems (CNHS). We characterize the primary social and ecological dimensions of the wildfire risk pathology, paying particular attention to the governance system around wildfire risk, and suggest strategies to mitigate the pathology through innovative planning approaches, analytical tools, and policies. We caution that even with a clear understanding of the problem and possible solutions, the system by which human actors govern fire-prone forests may evolve incrementally in imperfect ways and can be expected to resist change even as we learn better ways to manage CNHS
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