2,887 research outputs found

    Spatio-Temporal Low Count Processes with Application to Violent Crime Events

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    There is significant interest in being able to predict where crimes will happen, for example to aid in the efficient tasking of police and other protective measures. We aim to model both the temporal and spatial dependencies often exhibited by violent crimes in order to make such predictions. The temporal variation of crimes typically follows patterns familiar in time series analysis, but the spatial patterns are irregular and do not vary smoothly across the area. Instead we find that spatially disjoint regions exhibit correlated crime patterns. It is this indeterminate inter-region correlation structure along with the low-count, discrete nature of counts of serious crimes that motivates our proposed forecasting tool. In particular, we propose to model the crime counts in each region using an integer-valued first order autoregressive process. We take a Bayesian nonparametric approach to flexibly discover a clustering of these region-specific time series. We then describe how to account for covariates within this framework. Both approaches adjust for seasonality. We demonstrate our approach through an analysis of weekly reported violent crimes in Washington, D.C. between 2001-2008. Our forecasts outperform standard methods while additionally providing useful tools such as prediction intervals

    Treatments for women with gestational diabetes mellitus: an overview of Cochrane systematic reviews

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    Background Successful treatments for gestational diabetes mellitus (GDM) have the potential to improve health outcomes for women with GDM and their babies. Objectives To provide a comprehensive synthesis of evidence from Cochrane systematic reviews of the benefits and harms associated with interventions for treating GDM on women and their babies. Methods We searched the Cochrane Database of Systematic Reviews (5 January 2018) for reviews of treatment/management for women with GDM. Reviews of pregnant women with pre-existing diabetes were excluded. Two overview authors independently assessed reviews for inclusion, quality (AMSTAR; ROBIS), quality of evidence (GRADE), and extracted data. Main results We included 14 reviews. Of these, 10 provided relevant high-quality and low-risk of bias data (AMSTAR and ROBIS) from 128 randomised controlled trials (RCTs), 27 comparisons, 17,984 women, 16,305 babies, and 1441 children. Evidence ranged from high to very low-quality (GRADE). Only one effective intervention was found for treating women with GDM. Effective Lifestyle versus usual care Lifestyle intervention versus usual care probably reduces large-for-gestational age (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.50 to 0.71; 6 RCTs, N = 2994; GRADE moderate-quality). Promising No evidence for any outcome for any comparison could be classified to this category. Ineffective or possibly harmful Lifestyle versus usual care Lifestyle intervention versus usual care probably increases the risk of induction of labour (IOL) suggesting possible harm (average RR 1.20, 95% CI 0.99 to 1.46; 4 RCTs, N = 2699; GRADE moderate-quality). Exercise versus control Exercise intervention versus control for return to pre-pregnancy weight suggested ineffectiveness (body mass index, BMI) MD 0.11 kg/m², 95% CI -1.04 to 1.26; 3 RCTs, N = 254; GRADE moderate-quality). Insulin versus oral therapy Insulin intervention versus oral therapy probably increases the risk of IOL suggesting possible harm (RR 1.3, 95% CI 0.96 to 1.75; 3 RCTs, N = 348; GRADE moderate-quality). Probably ineffective or harmful interventions Insulin versus oral therapy For insulin compared to oral therapy there is probably an increased risk of the hypertensive disorders of pregnancy (RR 1.89, 95% CI 1.14 to 3.12; 4 RCTs, N = 1214; GRADE moderate-quality). Inconclusive Lifestyle versus usual care The evidence for childhood adiposity kg/m² (RR 0.91, 95% CI 0.75 to 1.11; 3 RCTs, N = 767; GRADE moderate-quality) and hypoglycaemia was inconclusive (average RR 0.99, 95% CI 0.65 to 1.52; 6 RCTs, N = 3000; GRADE moderate-quality). Exercise versus control The evidence for caesarean section (RR 0.86, 95% CI 0.63 to 1.16; 5 RCTs, N = 316; GRADE moderate quality) and perinatal death or serious morbidity composite was inconclusive (RR 0.56, 95% CI 0.12 to 2.61; 2 RCTs, N = 169; GRADE moderate-quality). Insulin versus oral therapy The evidence for the following outcomes was inconclusive: pre-eclampsia (RR 1.14, 95% CI 0.86 to 1.52; 10 RCTs, N = 2060), caesarean section (RR 1.03, 95% CI 0.93 to 1.14; 17 RCTs, N = 1988), large-for-gestational age (average RR 1.01, 95% CI 0.76 to 1.35; 13 RCTs, N = 2352), and perinatal death or serious morbidity composite (RR 1.03; 95% CI 0.84 to 1.26; 2 RCTs, N = 760). GRADE assessment was moderate-quality for these outcomes. Insulin versus diet The evidence for perinatal mortality was inconclusive (RR 0.74, 95% CI 0.41 to 1.33; 4 RCTs, N = 1137; GRADE moderate-quality). Insulin versus insulin The evidence for insulin aspart versus lispro for risk of caesarean section was inconclusive (RR 1.00, 95% CI 0.91 to 1.09; 3 RCTs, N = 410; GRADE moderate quality). No conclusions possible No conclusions were possible for: lifestyle versus usual care (perineal trauma, postnatal depression, neonatal adiposity, number of antenatal visits/admissions); diet versus control (pre-eclampsia, caesarean section); myo-inositol versus placebo (hypoglycaemia); metformin versus glibenclamide (hypertensive disorders of pregnancy, pregnancy-induced hypertension, death or serious morbidity composite, insulin versus oral therapy (development of type 2 diabetes); intensive management versus routine care (IOL, large-for-gestational age); post- versus pre-prandial glucose monitoring (large-for-gestational age). The evidence ranged from moderate-, low- and very low quality. Authors’ conclusions Currently there is insufficient high-quality evidence about the effects on health outcomes of relevance for women with GDM and their babies for many of the comparisons in this overview comparing treatment interventions for women with GDM. Lifestyle changes (including as a minimum healthy eating, physical activity and self-monitoring of blood sugar levels) was the only intervention that showed possible health improvements for women and their babies. Lifestyle interventions may result in fewer babies being large. Conversely, in terms of harms, lifestyle interventions may also increase the number of inductions. Taking insulin was also associated with an increase in hypertensive disorders, when compared to oral therapy. There was very limited information on long-term health and health services costs. Further high-quality research is needed

    The Surface of 2003 EL_(61) in the Near-Infrared

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    We report the detection of crystalline water ice on the surface of 2003 EL_(61). Reflectance spectra were collected from the Gemini North telescope in the 1.0 to 2.4 μm wavelength range and from the Keck telescope across the 1.4-2.4 μm wavelength range. The signature of crystalline water ice is obvious in all data collected. Like the surfaces of many outer solar system bodies, the surface of 2003 EL_(61) is rich in crystalline water ice, which is energetically less favored than amorphous water ice at low temperatures, suggesting that resurfacing processes may be taking place. The near-infrared color of the object is much bluer than a pure water ice model. Adding a near-infrared blue component such as hydrogen cyanide or phyllosilicate clays improves the fit considerably, with hydrogen cyanide providing the greatest improvement. The addition of hydrated tholins and bitumens also improves the fit, but is inconsistent with the neutral V - J reflectance of 2003 EL_(61). A small decrease in reflectance beyond 2.3 μm may be attributable to cyanide salts. Overall, the reflected light from 2003 EL_(61) is best fit by a model of 2/3-4/5 pure crystalline water ice and 1/3-1/5 near-infrared blue component such as hydrogen cyanide or kaolinite. The surface of 2003 EL_(61) is unlikely to be covered by significant amounts of dark material such as carbon black, as our pure ice models reproduce published albedo estimates derived from the spin state of 2003 EL_(61)

    Whole genome sequence analysis reveals the broad distribution of the RtxA type 1 secretion system and four novel putative type 1 secretion systems throughout the Legionella genus.

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    Type 1 secretion systems (T1SSs) are broadly distributed among bacteria and translocate effectors with diverse function across the bacterial cell membrane. Legionella pneumophila, the species most commonly associated with Legionellosis, encodes a T1SS at the lssXYZABD locus which is responsible for the secretion of the virulence factor RtxA. Many investigations have failed to detect lssD, the gene encoding the membrane fusion protein of the RtxA T1SS, in non-pneumophila Legionella, which has led to the assumption that this system is a virulence factor exclusively possessed by L. pneumophila. Here we discovered RtxA and its associated T1SS in a novel Legionella taurinensis strain, leading us to question whether this system may be more widespread than previously thought. Through a bioinformatic analysis of publicly available data, we classified and determined the distribution of four T1SSs including the RtxA T1SS and four novel T1SSs among diverse Legionella spp. The ABC transporter of the novel Legionella T1SS Legionella repeat protein secretion system shares structural similarity to those of diverse T1SS families, including the alkaline protease T1SS in Pseudomonas aeruginosa. The Legionella bacteriocin (1-3) secretion systems T1SSs are novel putative bacteriocin transporting T1SSs as their ABC transporters include C-39 peptidase domains in their N-terminal regions, with LB2SS and LB3SS likely constituting a nitrile hydratase leader peptide transport T1SSs. The LB1SS is more closely related to the colicin V T1SS in Escherichia coli. Of 45 Legionella spp. whole genomes examined, 19 (42%) were determined to possess lssB and lssD homologs. Of these 19, only 7 (37%) are known pathogens. There was no difference in the proportions of disease associated and non-disease associated species that possessed the RtxA T1SS (p = 0.4), contrary to the current consensus regarding the RtxA T1SS. These results draw into question the nature of RtxA and its T1SS as a singular virulence factor. Future studies should investigate mechanistic explanations for the association of RtxA with virulence

    Improved Thermal and Mechanical Properties and Increased Miscibility of Polybenzoxazine in Blends with Functionalized Thermoplastics and Particles

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    The solubility, polymerization, and the macromolecular characterization of cured blends of BPA-based benzoxazine (BA-a) in end group tosylated poly(ethylene glycol) (mPEGOTs), polysulfone (PSUOTs), and poly(D,L-lactic acid) (PDLLAOTs) are studied and compared to their hydroxyl terminated analogues. The cure temperature for BA-a blends with tosylated polymers was reduced by ~60 °C compared to that of the pure BA-a. This confirms that the tosylated polymer is an accelerant for BA-a ring opening polymerization (ROP). There are two proposed mechanism for the production of free tosylate and cationic BA-a based initiators as a cure catalyst for BA-a ROP – where the former was detected by TGA-FTIR and TGA-MS. SEM confirmed a grafted polymer network from BA-a and mPEGOTs, P(BA-a)-graft-mPEGOTs, this homogenous microstructure was also found in PBA-a/PSUOTs blends. The glass transition temperature and the thermal stability of the P(BA-a)-graft-mPEGOTs can be tuned based on the composition of the BA-a/mPEGOTs resin. The potential applications of such grafted polymers may lead to novel materials for the biomedical plastics, electronics, membranes, and aerospace industries. Further blends were prepared with microparticles of silica (SiOH) and the tosylate- (SiOTs) and phenyl- (SiPh) functionalized analogues. Increased modulus of PBA-a was found in all silica blends, the reduction in cure temperature was found only in blends of BA-a and SiOTs. By SEM, PBA-a/SiOTs blends were determined to have a unique morphology. Three benzoxazine-based surfactants were synthesized from the coupling of p-hydroxy methylbenzoxazine with mPEGOTs. All three surfactants had good monomer loading, up to 4.72 monomer to surfactant by mass

    How medical students screen for HIV with standardized patients establishing care.

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    How Medical Students Screen for HIV with Standardized Patients Establishing Care AUTHORS Christopher J. Brown, B.S., B.A. Candidate; Emily J Noonan, PhD, MA; Laura A. Weingartner, PhD, MS BACKGROUND Approximately 1.1 million people in the U.S. are living with HIV. The US Preventive Services Task Force (USPSTF) recommends HIV testing for everyone 15-65 years old at least once regardless of sexual activity, with more frequent testing for those considered at risk. METHODS Rising third-year medical students were recorded taking health histories from standardized patients. These recordings were coded for HIV screening, including: risk factors such as unprotected sex, intravenous drug usage, multiple partners, patient/partner HIV status; contextualization by student as to how screening questions related to HIV; and discussion tone (accusatory, informative, or non-judgmental). RESULTS Of the 71 sampled encounters, students identified whether the patient knew their STI status without mentioning HIV status, and 10 students explicitly identified whether the patient knew their HIV status. Similarly, 13 students discussed the STI status of the patient’s partner(s) without mentioning HIV, while only 4 students discussed the HIV status of the patient’s partner(s). In total, only 7 out of 71 students recommended HIV testing to their patient. When discussing patient status, most students (34) were non-judgmental, but one used an accusatory tone while eight were informative. DISCUSSION The results show a lack of explicit HIV discussions and testing recommendations to patients despite USPSTF recommendations that all patients be tested. This study highlights that even when STI status is discussed, many students do not specify HIV status, an important distinction when providing preventive care. Future studies should address how perceived patient risk for HIV and patient identity impact HIV testing recommendations

    Effects of cochlear implantation on binaural hearing in adults with unilateral hearing loss

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    A FDA clinical trial was carried out to evaluate the potential benefit of cochlear implant (CI) use for adults with unilateral moderate-to-profound sensorineural hearing loss. Subjects were 20 adults with moderate-to-profound unilateral sensorineural hearing loss and normal or near-normal hearing on the other side. A MED-EL standard electrode was implanted in the impaired ear. Outcome measures included: (a) sound localization on the horizontal plane (11 positions, −90° to 90°), (b) word recognition in quiet with the CI alone, and (c) masked sentence recognition with the target at 0° and the masker at −90°, 0°, or 90°. This battery was completed preoperatively and at 1, 3, 6, 9, and 12 months after CI activation. Normative data were also collected for 20 age-matched control subjects with normal or near-normal hearing bilaterally. The CI improved localization accuracy and reduced side bias. Word recognition with the CI alone was similar to performance of traditional CI recipients. The CI improved masked sentence recognition when the masker was presented from the front or from the side of normal or near-normal hearing. The binaural benefits observed with the CI increased between the 1- and 3-month intervals but appeared stable thereafter. In contrast to previous reports on localization and speech perception in patients with unilateral sensorineural hearing loss, CI benefits were consistently observed across individual subjects, and performance was at asymptote by the 3-month test interval. Cochlear implant settings, consistent CI use, and short duration of deafness could play a role in this result

    Admissions Criteria as Predictors of Academic Success in First- and Second- Year Osteopathic Medical Students

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    Overall undergraduate grade point average (GPA), Science GPA, and MCAT scores (Medical College Admission Test) are nationally used as the leading criteria for medical school recruitment and admission, and therefore treated as the primary predictors of academic success in medical schools. The model and practice of using statistical analysis to determine the justifiable use of certain admission criteria to predict academic performance in medical school has been researched but also recommends localized study. Using discriminant analysis (DA) theory as the analytical lens in this study, data from nine years of medical classes were collected for the participants, once upon matriculation into medical school and then collected again, after their second year of coursework, allowing for implications in the predictive value of the admissions criteria on student academic success or failure. This study found that 15 percent of the total group met the definition of academic difficulty. Science GPA seemed to best indicateSchool of Teaching and Curriculum Leadershi
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