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Urinary tract infections (UTIs) are common among college-aged women and often recur. Some antibiotics recommended to treat UTIs trigger dysbiosis of intestinal and vaginal microbiomes – where uropathogens originate, though few studies have investigated associations between these therapies with recurrent infections. We retrospectively analysed the electronic medical records of 6651 college-aged women diagnosed with a UTI at a US university student health centre between 2006 and 2014. Women were followed for 6 months for incidence of a recurrent infection. In a secondary analysis, associations in women whose experienced UTI recurrence within 2 weeks were also considered for potential infection relapse. Logistic regression was used to assess associations between infection recurrence or relapse and antibiotics prescribed, in addition to baseline patient characteristics including age, race/ethnicity, region of origin, year of encounter, presence of symptomology, pyelonephritis, vaginal coinfection and birth control consultation. There were 1051 instances of infection recurrence among the 6620 patients, indicating a prevalence of 16%. In the analysis of patient characteristics, Asian women were statistically more likely to experience infection recurrence whereas African American were less likely. No significant associations were identified between the antibiotic administered at the initial infection and the risk of infection recurrence after multivariable adjustment. Treatment with trimethoprim-sulphamethoxazole and being born outside of the USA were significantly associated with increased odds of infection relapse in the multivariate analysis. The results of the analyses suggest that treatment with trimethoprim-sulphamethoxazole may lead to an increased risk of UTI relapse, warranting further study.
To test the feasibility of using telehealth to support antimicrobial stewardship at Veterans Affairs medical centers (VAMCs) that have limited access to infectious disease-trained specialists.
A prospective quasi-experimental pilot study.
Two rural VAMCs with acute-care and long-term care units.
At each intervention site, medical providers, pharmacists, infection preventionists, staff nurses, and off-site infectious disease physicians formed a videoconference antimicrobial stewardship team (VAST) that met weekly to discuss cases and antimicrobial stewardship-related education.
Descriptive measures included fidelity of implementation, number of cases discussed, infectious syndromes, types of recommendations, and acceptance rate of recommendations made by the VAST. Qualitative results stemmed from semi-structured interviews with VAST participants at the intervention sites.
Each site adapted the VAST to suit their local needs. On average, sites A and B discussed 3.5 and 3.1 cases per session, respectively. At site A, 98 of 140 cases (70%) were from the acute-care units; at site B, 59 of 119 cases (50%) were from the acute-care units. The most common clinical syndrome discussed was pneumonia or respiratory syndrome (41% and 35% for sites A and B, respectively). Providers implemented most VAST recommendations, with an acceptance rate of 73% (186 of 256 recommendations) and 65% (99 of 153 recommendations) at sites A and B, respectively. Qualitative results based on 24 interviews revealed that participants valued the multidisciplinary aspects of the VAST sessions and felt that it improved their antimicrobial stewardship efforts and patient care.
This pilot study has successfully demonstrated the feasibility of using telehealth to support antimicrobial stewardship at rural VAMCs with limited access to local infectious disease expertise.
The adenovirus vaccine and benzathine penicillin G (BPG) have been used by the US military to prevent acute respiratory diseases (ARD) in trainees, though these interventions have had documented manufacturing problems. We fit Poisson regression and random forest models (RF) to 26 years of weekly ARD incidence data to explore the impact of the adenovirus vaccine and BPG prophylaxis on respiratory disease burden. Adenovirus vaccine availability was among the most important predictors of ARD in the RF, while BPG was the ninth most important. BPG was a significant protective factor against ARD (incidence rate ratio (IRR) = 0.68; 95% confidence interval (CI) 0.67–0.70), but less so than either the old or new adenovirus vaccine (IRR = 0.39, 95% CI 0.38–0.39 and IRR = 0.11, 95% CI 0.11–0.11), respectively. These results suggest that BPG is moderately predictive of, and significantly protective against ARD, though to a lesser extent than either the old or new adenovirus vaccine.
Brandãoite, [BeAl2(PO4)2(OH)2(H2O)4](H2O), is a new Be–Al phosphate mineral from the João Firmino mine, Pomarolli farm region, Divino das Laranjeiras County, Minas Gerais State, Brazil, where it occurs in an albite pocket with other secondary phosphates, including beryllonite, atencioite and zanazziite, in a granitic pegmatite. It occurs as colourless acicular crystals <10 µm wide and <100 µm long that form compact radiating spherical aggregates up to 1.0–1.5 mm across. It is colourless and transparent in single crystals and white in aggregates, has a white streak and a vitreous lustre, is brittle and has conchoidal fracture. Mohs hardness is 6, and the calculated density is 2.353 g/cm3. Brandãoite is biaxial (+), α = 1.544, β = 1.552 and γ = 1.568, all ± 0.002; 2Vobs = 69.7(10)° and 2Vcalc = 71.2°. No pleochroism was observed. Brandãoite is triclinic, space group P
, a = 6.100(4), b = 8.616(4), c = 10.261(5) Å, α = 93.191(11), β = 95.120(11), γ = 96.863(11)°, V = 532.1(8) Å3 and Z = 2. Chemical analysis of a 4 µm wide needle-shaped crystal by electron microprobe and secondary-ion mass spectrometry gave P2O5 = 28.42, Al2O3 = 20.15, BeO = 4.85, H2O = 21.47 and sum = 74.89 wt.%. The empirical formula, normalised on the basis of 15 anions pfu with (OH) = 2 and (H2O) = 5 apfu (from the crystal structure) is Be0.98Al1.99P2.02H12O15. The crystal structure was solved by direct methods and refined to an R1 index of 7.0%. There are two P sites occupied by P5+, two Al sites occupied by octahedrally coordinated Al3+, and one Be site occupied by tetrahedrally coordinated Be2+. There are fifteen anions, two of which are (OH) groups and five of which are (H2O) groups. The simplified ideal formula is thus [BeAl2(PO4)2(OH)2(H2O)4](H2O) with Z = 2. Beryllium and P tetrahedra share corners to form a four-membered ring. Aluminium octahedra share a common vertex to form an [Al2φ11] dimer, and these dimers are cross-linked by P tetrahedra to form a complex slab of polyhedra parallel to (001). These slabs are cross-linked by BeO2(OH)(H2O) tetrahedra, with interstitial (H2O) groups in channels that extend along .
We use ceramic and obsidian data from the ancient Maya port site of Vista Alegre to discuss long-distance exchange during the Terminal Classic (c. AD 850–1100) period. This is a time often associated with increased international trade relations and the growth of Chichen Itza as a dominant regional power in the northern Maya lowlands. Critical to the increased volume of international trade were the merchants who transported goods along the coast of Yucatan in large trading canoes. By combining a macroscopic assessment of the ceramics with visual, XRF, and INAA analyses of the obsidian artifacts, we gain insight into the various socioeconomic forces at work moving goods around the Peninsula. Given the paucity of Terminal Classic settlement in the interior Yalahau region, Vista Alegre appears to be an isolated site during this period, approximately 40 km from the nearest coastal neighbor. This allows us to focus on coastal exchange as the sole means by which goods arrived at the site. Our preliminary data contribute to the growing literature on the role market economies played in the Maya area, and the increased opportunities this afforded coastal peoples as circum-peninsular trade became more common through time.
The overall objective of a series of experiments to investigate ‘metabolic stress’ was to examine the relationships between ‘metabolic load’, disease and other parameters associated with the welfare of the dairy cow. In the main, these used several well controlled herd based studies complimented with more basic and strategic investigations. In this paper we compare and contrast practical aspects of health and welfare in two high genetic merit herds managed at the extremes of inputs and outputs for dairy farming in south-west Scotland. The hypothesis was that high output herds would have more health and welfare problems than low input herds. Two herds (70 Holstein-Friesian cows each) at SAC Acrehead Dumfries of a similar genetic background (overall in the top 5% of UK cows by PIN and ITEM), were housed in identical buildings and tended by the same herdsman. Both herds had autumn- and spring-calving cattle. The ‘low input’ herd (LI) was given a minimum of concentrate (approx. 0.5 t per cow per year) and milked twice a day and had a restricted quota of 385 000 l. The ‘high output’ herd (HO) was managed for high yields (unrestricted quota) and was given concentrates (2 t per cow per year) and forage ad libitum and milked three times daily. In 1995-96 the sole source of winter forage was grass/clover silage (LI) or grass silage (HO) but in 1996-1998 ensiled cereal and fodder beet were included in both diets. ‘Metabolic load’ could only be inferred from overall inputs, milk outputs, weight loss, body condition score and behaviour. There were significant differences in 305-day lactation yields between herds, and season of calving especially in 1995-96 (LI autumn; 5952 l at 30 g/kg protein (P); LI spring; 5741 l, 32.5 g/kg P; HO autumn; 9541 l at 32.8 g/kg P; HO spring; 8402 l, 32.6 g/kg P). LI weight and body condition-score losses were greatest in this year and behavioural studies showed substantial differences in feeding time (HO < LI, P < 0.05) and total lying time (LI < HO; P < 0.05). However these differences were much less marked in subsequent years. There was a significant difference in the prevalence and incidence of clinical lameness between herds (HO > LI; P < 0.05) and season (autumn > spring P < 0.05) but not for mastitis or metabolic disease. An in-depth study of subclinical claw horn lesion development in first calving heifers showed significant differences between herds in 1996-97 (LI > HO, P < 0.05) but none in 1995-96. There was a significant difference for season in both years (autumn > spring, P < 0.05). Analysis of blood biochemistry parameters of samples taken at approximately 1 month after calving showed some significant differences between LI and HO generally indicating a greater ‘metabolic load’ for LI. Although the full effects of ‘metabolic load’ on immune function and reproduction are dealt with elsewhere our preliminary data showed no significant differences between herds for the former but some significant differences for the latter, in particular there were differences in aspects of the progesterone profiles between herds and more importantly between seasons. However these latter differences were not clearly reflected in conception rates. It was concluded that the hypothesis was not fully sustained and that both systems had pitfalls in terms of welfare. The three major areas causing difficulties for both systems were the need first to ensure adequate intake of forage; secondly to limit the environmental challenge to the feet and udder and finally to marry these systems to the factors limiting reproduction, primarily calving season and ability of reproduction management.
Obsessive–compulsive disorder (OCD) has been linked to functional abnormalities in fronto-striatal networks as well as impairments in decision making and learning. Little is known about the neurocognitive mechanisms causing these decision-making and learning deficits in OCD, and how they relate to dysfunction in fronto-striatal networks.
We investigated neural mechanisms of decision making in OCD patients, including early and late onset of disorder, in terms of reward prediction errors (RPEs) using functional magnetic resonance imaging. RPEs index a mismatch between expected and received outcomes, encoded by the dopaminergic system, and are known to drive learning and decision making in humans and animals. We used reinforcement learning models and RPE signals to infer the learning mechanisms and to compare behavioural parameters and neural RPE responses of the OCD patients with those of healthy matched controls.
Patients with OCD showed significantly increased RPE responses in the anterior cingulate cortex (ACC) and the putamen compared with controls. OCD patients also had a significantly lower perseveration parameter than controls.
Enhanced RPE signals in the ACC and putamen extend previous findings of fronto-striatal deficits in OCD. These abnormally strong RPEs suggest a hyper-responsive learning network in patients with OCD, which might explain their indecisiveness and intolerance of uncertainty.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
Confocal laser scanning microscopy is a well-established optical technique allowing for three-dimensional (3-D) visualization of fluorescent specimens with a resolution close to the diffraction limit of light. Thanks to the availability of a wide range of fluorescent dyes and selective staining using antibodies, the technique is commonly used in life sciences as a powerful tool for studying different biological processes, often at the level of single molecules. However, this type of approach is often not applicable for specimens that are preserved in historical slide collections, embedded in amber, or are fossilized, and cannot be exposed to any form of selective staining or other form of destructive treatment. This usually narrows the number of microscopic techniques that can be used to study such specimens to traditional light microscopy or scanning electron microscopy. However, these techniques have their own limitations and cannot fully reveal 3-D structures within such barely accessible samples. Can confocal microscopy be of any help? The answer is positive, and it is due to the fact that many paleontological specimens exhibit a strong inherent autofluorescence that can serve as an excellent source of emitted photons for confocal microscopy visualizations either through reconstruction of the induced autoflourescent signal from the sample, or through reconstruction of the reflected signal from the sample surface. Here, we describe the workflow and methodology involved in acquiring confocal data from a sample and reprocessing the resulting image stack using the image-processing program imageJ before reconstructing the data using the open-source 3-D rendering program, Drishti. This approach opens new possibilities for using confocal microscopy in a nondestructive manner for visualizing complex paleontological material that has never previously been considered as suitable for this type of microscopic technique.
The evolution of a tandem accelerator 14C dating system at Chalk River is recounted. Background problems and sources of instability are discussed and solutions are described. Details of sample chemistry and source preparation are presented.
The Chalk River Tandem Accelerator Mass Spectrometry System has reached a state of reliable measurement of 14C using 2 to 5mg elemental carbon prepared by Mg reduction of CO2. For two comparisons of a near-modern unknown with the NBS oxalic acid standard we obtain a total error of ∼±4.5%, consisting of a random system error of about ±3.5% combined with the statistical counting error. Measurements have been made on 70 samples in 30 days of running time during the past year. Samples included deep rock carbonates, cosmogenic 14C in meteorites, charcoal from earthquake fault zones, collagen of bone artifacts and fossil beetle-fragments.
Shock drift acceleration of the electrons which produce herringbone structure in type II bursts is considered. A non-coplanar component of the magnetic field within the shock front and an electric field across the shock are taken into account. A quantitative difficulty with shock drift acceleration is identified, and possible ways of overcoming the difficulty are outlined.
A simple model is presented for electron acceleration in extragalactic radio sources with two hot spots. The effect of diffusive shock acceleration by multiple shocks is calculated numerically, with adiabatic and synchrotron losses included. It is found for the sources 3C 20 and 3C 268·4 that a consistent set of model parameters exists which reproduce the observations. The model fails to reproduce the observations for the source 3C 196.
We describe an image dissector photoelectric system that is used for acquisition, guiding, focussing, and photometric monitoring in telescope control. A similar system is used for area scanning and spectrophotometry.
Increasing recognition of the extent to which nitrous oxide (N2O) contributes to climate change has resulted in greater demand to improve quantification of N2O emissions, identify emission sources and suggest mitigation options. Agriculture is by far the largest source and grasslands, occupying c. 0·22 of European agricultural land, are a major land-use within this sector. The application of mineral fertilizers to optimize pasture yields is a major source of N2O and with increasing pressure to increase agricultural productivity, options to quantify and reduce emissions whilst maintaining sufficient grassland for a given intensity of production are required. Identification of the source and extent of emissions will help to improve reporting in national inventories, with the most common approach using the IPCC emission factor (EF) default, where 0·01 of added nitrogen fertilizer is assumed to be emitted directly as N2O. The current experiment aimed to establish the suitability of applying this EF to fertilized Scottish grasslands and to identify variation in the EF depending on the application rate of ammonium nitrate (AN). Mitigation options to reduce N2O emissions were also investigated, including the use of urea fertilizer in place of AN, addition of a nitrification inhibitor dicyandiamide (DCD) and application of AN in smaller, more frequent doses. Nitrous oxide emissions were measured from a cut grassland in south-west Scotland from March 2011 to March 2012. Grass yield was also measured to establish the impact of mitigation options on grass production, along with soil and environmental variables to improve understanding of the controls on N2O emissions. A monotonic increase in annual cumulative N2O emissions was observed with increasing AN application rate. Emission factors ranging from 1·06–1·34% were measured for AN application rates between 80 and 320 kg N/ha, with a mean of 1·19%. A lack of any significant difference between these EFs indicates that use of a uniform EF is suitable over these application rates. The mean EF of 1·19% exceeds the IPCC default 1%, suggesting that use of the default value may underestimate emissions of AN-fertilizer-induced N2O loss from Scottish grasslands. The increase in emissions beyond an application rate of 320 kg N/ha produced an EF of 1·74%, significantly different to that from lower application rates and much greater than the 1% default. An EF of 0·89% for urea fertilizer and 0·59% for urea with DCD suggests that N2O quantification using the IPCC default EF will overestimate emissions for grasslands where these fertilizers are applied. Large rainfall shortly after fertilizer application appears to be the main trigger for N2O emissions, thus applicability of the 1% EF could vary and depend on the weather conditions at the time of fertilizer application.
Sufficient dairy food consumption during adolescence is necessary for preventing disease. While socio-economically disadvantaged adolescents tend to consume few dairy foods, some eat quantities more in line with dietary recommendations despite socio-economic challenges. Socio-economic variations in factors supportive of adolescents’ frequent dairy consumption remain unexplored. The present study aimed to identify cross-sectional and longitudinal associations between intrapersonal, social and environmental factors and adolescents’ frequent dairy consumption at baseline and two years later across socio-economic strata, and to examine whether socio-economic position moderated observed effects.
Online surveys completed at baseline (2004–2005) and follow-up (2006–2007) included a thirty-eight-item FFQ and questions based on social ecological models examining intrapersonal, social and environmental dietary influences.
Thirty-seven secondary schools in Victoria, Australia.
Australian adolescents (n 1201) aged 12–15 years, drawn from a sub-sample of 3264 adolescents (response rate=33 %).
While frequent breakfast consumption was cross-sectionally associated with frequent dairy consumption among all adolescents, additional associated factors differed by socio-economic position. Baseline dairy consumption longitudinally predicted consumption at follow-up. No further factors predicted frequent consumption among disadvantaged adolescents, while four additional factors were predictive among advantaged adolescents. Socio-economic position moderated two predictors; infrequently eating dinner alone and never purchasing from school vending machines predicted frequent consumption among advantaged adolescents.
Nutrition promotion initiatives aimed at improving adolescents’ dairy consumption should employ multifactorial approaches informed by social ecological models and address socio-economic differences in influences on eating behaviours; e.g. selected intrapersonal factors among all adolescents and social factors (e.g. mealtime rules) among advantaged adolescents.