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Lithium-treated patients with polyuria are at increased risk of lithium toxicity. We aimed to describe the clinical benefits and risks of different management strategies for polyuria in community lithium-treated patients.
This is a naturalistic, observational, prospective 12-month cohort study of lithium-treated patients with polyuria attending a community mental health service in Dublin, Ireland. When polyuria was detected, management changed in one of four ways: (a) no pharmacological change; (b) lithium dose decrease; (c) lithium substitution; or (d) addition of amiloride.
Thirty-four participants were diagnosed with polyuria and completed prospective data over 12 months. Mean 24-hour urine volume decreased from 4852 to 4344 ml (p = 0.038). Mean early morning urine osmolality decreased from 343 to 338 mOsm/kg (p = 0.823). Mean 24-hour urine volume decreased with each type of intervention but did not attain statistical significance for any individual intervention group. Mean early morning urine osmolality decreased in participants with no pharmacological change and increased in participants who received a change in medication but these changes did not attain statistical significance. Only participants who discontinued lithium demonstrated potentially clinically significant changes in urine volume (mean decrease 747 ml in 24 hours) and early morning urine osmolality (mean increase 31 mOsm/kg) although this was not definitively proven, possibly owing to power issues.
Managing polyuria by decreasing lithium dose does not appear to substantially improve objective measures of renal tubular dysfunction, whereas substituting lithium may do so. Studies with larger numbers and longer follow-up would clarify these relationships.
Disease surveillance in wildlife populations presents a logistical challenge, yet is critical in gaining a deeper understanding of the presence and impact of wildlife pathogens. Erinaceus coronavirus (EriCoV), a clade C Betacoronavirus, was first described in Western European hedgehogs (Erinaceus europaeus) in Germany. Here, our objective was to determine whether EriCoV is present, and if it is associated with disease, in Great Britain (GB). An EriCoV-specific BRYT-Green® real-time reverse transcription PCR assay was used to test 351 samples of faeces or distal large intestinal tract contents collected from casualty or dead hedgehogs from a wide area across GB. Viral RNA was detected in 10.8% (38) samples; however, the virus was not detected in any of the 61 samples tested from Scotland. The full genome sequence of the British EriCoV strain was determined using next generation sequencing; it shared 94% identity with a German EriCoV sequence. Multivariate statistical models using hedgehog case history data, faecal specimen descriptions and post-mortem examination findings found no significant associations indicative of disease associated with EriCoV in hedgehogs. These findings indicate that the Western European hedgehog is a reservoir host of EriCoV in the absence of apparent disease.
Although most hospitals report very high levels of hand hygiene compliance (HHC), the accuracy of these overtly observed rates is questionable due to the Hawthorne effect and other sources of bias. In the study, we aimed (1) to compare HHC rates estimated using the standard audit method of overt observation by a known observer and a new audit method that employed a rapid (<15 minutes) “secret shopper” method and (2) to pilot test a novel feedback tool.
Quality improvement project using a quasi-experimental stepped-wedge design.
This study was conducted in 5 acute-care hospitals (17 wards, 5 intensive care units) in the Midwestern United States.
Sites recruited a hand hygiene observer from outside the acute-care units to rapidly and covertly observe entry and exit HHC during the study period, October 2016–September 2017. After 3 months of observations, sites received a monthly feedback tool that communicated HHC information from the new audit method.
The absolute difference in HHC estimates between the standard and new audit methods was ~30%. No significant differences in HHC were detected between the baseline and feedback phases (OR, 0.92; 95% CI, 0.84–1.01), but the standard audit method had significantly higher estimates than the new audit method (OR, 9.83; 95% CI, 8.82–10.95).
HHC estimates obtained using the new audit method were substantially lower than estimates obtained using the standard audit method, suggesting that the rapid, secret-shopper method is less subject to bias. Providing feedback using HHC from the new audit method did not seem to impact HHC behaviors.
In Cameroon, there is a national programme engaged in the control of schistosomiasis and soil-transmitted helminthiasis. In certain locations, the programme is transitioning from morbidity control towards local interruption of parasite transmission. The volcanic crater lake villages of Barombi Mbo and Barombi Kotto are well-known transmission foci and are excellent context-specific locations to assess appropriate disease control interventions. Most recently they have served as exemplars of expanded access to deworming medications and increased environmental surveillance. In this paper, we review infection dynamics through time, beginning with data from 1953, and comment on the short- and long-term success of disease control. We show how intensification of local control is needed to push towards elimination and that further environmental surveillance, with targeted snail control, is needed to consolidate gains in preventive chemotherapy as well as empower local communities to take ownership of interventions.
Exotic crops—plant species grown in relatively small quantities and not traditionally cultivated in a country or region—are often intimately linked with the ethnic origins of their maintainers and are a principal source of culinary and nutritional diversity for many people. Recognizing that a wealth of exotic crop diversity and associated knowledge is held by small-scale growers in the UK, Garden Organic initiated the Sowing New Seeds project to capture and preserve some of this valuable resource by building a seed collection and knowledge base. To establish a sample of this diversity and knowledge, we undertook a survey at 31 allotment sites in the Midlands region of the UK with the objectives of identifying the exotic crops cultivated, characterizing the demography of those who grow them, understanding their direct use values, and assessing their potential indirect use value for the diversification and improvement of other crops. Results reveal that 26% of the food crops recorded are exotic and that they are grown by people belonging to 13 different ethnic groups. The majority save their own seed, indicating that these crops are performing well in the UK, with grower selection providing the basis for their continuing success. Further, most maintainers swap seed with other growers, indicating that exotic crops are likely to be gradually diversifying in response to different growing conditions—a positive sign for their value for local food security and as national genetic resources with potential for use in crop improvement programs. The research highlights the multitude of benefits that growers obtain through cultivating exotic crops, which are not only related to nutrition and culinary requirements, but also to general health and well-being, culture, and a range of other forms of life enrichment. It is critical that growers are encouraged and supported in continuing to cultivate, save and pass on their exotic crops to younger generations, as well as to protect allotments from development in order to maintain this important diversity adapted to local growing conditions. Importantly, many exotic crops currently grown on a small scale may enter into commerce, and thus expand the diversity of the UK's food crop base. Such a shift may be particularly important in the face of the increasingly detrimental impacts of climate change on crop production. We conclude that exotic crop diversity could be more important for future nutrition, health and food security than we currently appreciate.
To determine the scope, source, and mode of transmission of a multifacility outbreak of extensively drug-resistant (XDR) Acinetobacter baumannii.
SETTING AND PARTICIPANTS
Residents and patients in skilled nursing facilities, long-term acute-care hospital, and acute-care hospitals.
A case was defined as the incident isolate from clinical or surveillance cultures of XDR Acinetobacter baumannii resistant to imipenem or meropenem and nonsusceptible to all but 1 or 2 antibiotic classes in a patient in an Oregon healthcare facility during January 2012–December 2014. We queried clinical laboratories, reviewed medical records, oversaw patient and environmental surveillance surveys at 2 facilities, and recommended interventions. Pulsed-field gel electrophoresis (PFGE) and molecular analysis were performed.
We identified 21 cases, highly related by PFGE or healthcare facility exposure. Overall, 17 patients (81%) were admitted to either long-term acute-care hospital A (n=8), or skilled nursing facility A (n=8), or both (n=1) prior to XDR A. baumannii isolation. Interfacility communication of patient or resident XDR status was not performed during transfer between facilities. The rare plasmid-encoded carbapenemase gene blaOXA-237 was present in 16 outbreak isolates. Contact precautions, chlorhexidine baths, enhanced environmental cleaning, and interfacility communication were implemented for cases to halt transmission.
Interfacility transmission of XDR A. baumannii carrying the rare blaOXA-237 was facilitated by transfer of affected patients without communication to receiving facilities.
Nitrogen, one of the most abundant elements in the Universe is a fundamental element of molecules which are crucial for life. We present here the modelling of the emission of two of the simplest nitrogen-bearing molecules, CN and NO, with a non-LTE radiative transfer code in IRAS16293-2422, a class 0 low-mass protostar. In this model, we assumed IRAS16293-2422 is formed by 2 compact, hot and dense sources embedded in a three layers of envelope.
Isocyanic acid (HNCO) is a simple molecule containing the four main atoms essential for life and can be considered as a prebiotic molecule. To model the HNCO emission in the IRAS16293-2422 class 0 low-mass protostar, we used a new set of HNCO collisional coefficients with ortho-H2 and para-H2, computed from a set of rotational excitation quenching rates between HNCO and H2 based on a novel potential energy surface for the rigid molecules interactions. We present here the HNCO Potential Energy Surface used to compute this new set of collisional coefficients and the result of the IRAS16293-2422 HNCO spectrum modelling using them.
Far-UV photons (FUV, E < 13.6 eV) from hot massive stars regulate, or at least influence, the heating, ionization, and chemistry of most of the neutral interstellar medium (H i and H2 clouds). Investigating the interaction between FUV radiation and interstellar matter (molecules, atoms and grains) thus plays an important role in astrochemistry.
The Orion Bar, an interface region between the Orion A molecular cloud and the H ii region around the Trapezium cluster, is a textbook example of a strongly illuminated dense PDR (photodissociation region). The Bar is illuminated by a FUV field of a few 104 times the mean interstellar radiation field. Because of its proximity and nearly edge-on orientation, it provides a very good template to investigate the chemical content, structure, and dynamics of a strongly irradiated molecular cloud edge. We have used ALMA to mosaic a small field of the Bar where the critical transition from atomic to molecular gas takes place. These observations provide an unprecedented sharp view of this transition layer (≲ 1″ resolution or ≲ 414 AU). The resulting images (so far in the rotational emission of CO, HCO+, H13CO+, SO+, SO, and reactive ions SH+ and HOC+) show the small-scale structure in gas density and temperature, and the steep abundance gradients. The images reveal a pattern of high-density substructures, photo-ablative gas flows and instabilities at the edge of the molecular cloud. These first ALMA images thus show a more complex morphology than the classical clump/interclump static model of a PDR.
In order to quantify the chemical content in strongly FUV-irradiated gas, we have also used the IRAM-30 m telescope to carry out a complete line-survey of the illuminated edge of the Bar in the millimeter domain. Our observations reveal the presence of complex organic molecules (and precursors) that were not expected in such a harsh environment. In particular, we have reported the first detection of the unstable cis conformer of formic acid (HCOOH) in the ISM. The energy barrier to internal rotation (the conversion from trans to cis) is approximately 4827 cm−1 (≈7000 K). Hence, this detection is surprising. The low inferred trans-to-cis abundance ratio of 2.8±1.0 supports a photoswitching mechanism: a given conformer absorbs a FUV stellar photon that radiatively excites the molecule to electronic states above the interconversion barrier. Subsequent fluorescent decay leaves the molecule in a different conformer form. This mechanism, which we have specifically studied with ab initio quantum calculations, was not considered so far in astrochemistry although it can affect the structure of a variety of molecules in PDRs.
A series of catalytic reactions has been performed in our laboratory using olivine-type silicates (OTS) and SiC as catalysts for the conversion of carbon-containing molecules (such as acetylene, CO and methanol) to small organic molecules (C2H4, C3H3, CH3O) and also polycyclic aromatic hydrocarbons (PAHs). Experimentally, small-to-medium-sized gas-phase compounds such as PAHs, reaction intermediates and hydrocarbon compounds were detected in situ using the time-of-light mass-spectrometry technique. Solid deposition on the catalyst surface was examined by high-resolution transmission electron microscopy and thermo-gravimetric analysis techniques. Our laboratory results show that the conversion of acetylene to PAHs, the CO disproportionation reaction for producing CO2 and carbon deposition (graphitic and carbon nanostructures), and also the transformation of methanol to hydrocarbon compounds can easily be achieved with OTS as a catalyst. Furthermore, the conversion of acetylene to PAHs could also be achieved by SiC as the catalyst. It is proposed that these catalytic reactions mimic similar chemical processes in circumstellar envelopes (CSEs).
We describe the characteristics and the capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to generate, process and analyze interstellar, circumstellar and planetary analogs in the laboratory. COSmIC stands for ’Cosmic Simulation Chamber’ and is dedicated to the study of neutral and ionized molecules and nanoparticles under the low temperature and high vacuum conditions that are required to simulate various space environments such as diffuse interstellar clouds, circumstellar outflows and planetary atmospheres. Recent results obtained using COSmIC will be highlighted. In particular, the progress that has been achieved in the domain of the diffuse interstellar bands (DIBs) and in monitoring, in the laboratory, the formation of circumstellar dust grains and planetary atmosphere aerosols from their gas-phase molecular precursors. Plans for future laboratory experiments on interstellar and planetary molecules and grains will also be addressed, as well as the implications of the studies underway for astronomical observations and past and future space mission data analysis.
In this work, one intends to computationally simulate and investigate, via thermochemical calculations, how the chemical environment influences some molecular properties, such as IR spectra and absorption cross section, of individual species embedded in the solid phase employing the Polarized Continuum Model (PCM) approach. The trial molecules used here to check these effects are CO, CO2 and H2O. The solid phase (bulk ice) is simulated using different dielectric constant values representing different types of astrophysical ice at PCM approach. The effect of temperature is also investigated since it is known it affects the dielectric constant of the solvent medium.
Results are presented from our ongoing studies of Titan using ALMA during the period 2012-2015, including a confirmation of the previous detection of vinyl cyanide (C2H3CN), as well as the first spatial map for this species on Titan. Simultaneous mapping of HC3N, CH3CN and C2H5CN reveal characteristic abundance patterns for each species that provide insight into their individual photochemical lifetimes, and help inform our understanding of Titan’s unique, time-variable atmospheric chemistry and global circulation. A time-sequence of HC3N maps covering 38 months reveals a dramatic change in the distribution of this gas consistent with high-altitude photochemical production followed by advection towards the southern (winter) pole, combined with rapid loss in the north after Titan’s 2009 seasonal equinox. The 2015 C2H3CN and C2H5CN maps show abundance peaks in Titan’s southern hemisphere, similar to those observed for the short-lived HC3N molecule. The longer-lived CH3CN, on the other hand, remains more concentrated in the north.
C2H4O2 isomers, methyl formate (HCOOCH3), acetic acid (CH3COOH) and glycoaldehyde (HOCH2CHO), have been detected in a lot of sources in ISM. However, their abundances are very different, with methyl formate much more abundant than the other two isomers. This fact may be related to the different destruction by ionizing radiation of these molecules. The goal of this work is experimentally study the photodissociation processes of methyl formate and acetic acid ices when exposed to broadband soft X-ray from 6 up to 2000 eV. The experiments were performed coupled to the SGM beamline in the Brazilian Synchrotron Light Source (LNLS/CNPEM) at Campinas, Brazil. The simulated astrophysical ices (12K) were monitored throughout the experiment using infrared vibrational spectroscopy. The analysis of processed ices allowed the determination of the effective destruction cross sections of the parent molecules as well as the effective formation cross section of daughter molecular species. The relative abundance between acetic acid and methyl formate (NCH3COOH/NHCOOCH3) in different astronomical scenarios and their column density evolution in the presence of X-rays were calculated and our results suggests that such radiation field can be one of the factors that explain the difference in the isomers C2H4O2 abundances. We also quantified the daugther species after the establishment of a chemical equilibrium in the samples.
Evidence from the Ross embayment, Antarctica, suggests an abrupt cooling and a concomitant increase in sea-ice cover at about 6000 BP (6 ka). Stable-isotope (δD) concentrations in the Taylor Dome ice core, at the western edge of the Ross embayment, decline rapidly after 6 ka, and continue to decline through the late Holocene. Methanesulfonic acid concentrations at Taylor Dome show opposite trends to δD Sediment cores from the western Ross Sea show a percentage minimum for the sea-ice diatom Fragilariopsis curta between 9 and 6 ka, whenTaylor Dome δD values are highest, followed by an increase through the late Holocene. Radiocarbon dates from raised beach deposits indicate that the retreat of ice shelves in the Ross embayment ceased at about 6 ka, coincident with the environmental changes inferred from the sediment and ice-core records. The similarity in timing suggests an important role for climate in controlling the evolution of ice-shelf margins following the end of the last glaciation.
To develop and evaluate a Nutrition Transition-FFQ (NT-FFQ) to measure nutrition transition among adolescents in South India.
We developed an interviewer-administered NT-FFQ comprising a 125-item semi-quantitative FFQ and a twenty-seven-item eating behaviour survey. The reproducibility and validity of the NT-FFQ were assessed using Spearman correlations, intra-class correlation coefficients (ICC), and levels of agreement using Bland–Altman and cross-classification over 2 months (NT-FFQ1 and NT-FFQ2). Validity of foods was evaluated against three 24-h dietary recalls (24-HR). Face validity of eating behaviours was evaluated through semi-structured cognitive interviews. The reproducibility of eating behaviours was assessed using weighted kappa (κw) and cross-classification analyses.
A representative sample of 198 adolescents aged 14–18 years.
Reproducibility of NT-FFQ: Spearman correlations ranged from 0·33 (pulses) to 0·80 (red meat) and ICC from 0·05 (fruits) to 1·00 (tea). On average, concordance (agreement) was 60 % and discordance was 7 % for food groups. For eating behaviours, κw ranged from 0·24 (eating snacks while watching television) to 0·67 (eating lunch at home) with a mean of 0·40. Validity of NT-FFQ: Spearman correlations ranged from 0·11 (fried traditional foods) to 0·70 (tea) and ICC ranged from 0·02 (healthy global foods) to 1·00 (grains). The concordance and discordance were 48 % and 8 %, respectively. Bland–Altman plots showed acceptable agreement between NT-FFQ2 and 24-HR. The eating behaviours had acceptable face validity.
The NT-FFQ has good reproducibility and acceptable validity for food intake and eating behaviours. The NT-FFQ can quantify the nutrition transition among Indian adolescents.
Parasite infection in young animals can affect host traits related to demographic processes such as survival and reproduction, and is therefore crucial to population viability. However, variation in infection among juvenile hosts is poorly understood. Experimental studies have indicated that effects of parasitism can vary with host sex, hatching order and hatch date, yet it remains unclear whether this is linked to differences in parasite burdens. We quantified gastrointestinal nematode burdens of wild juvenile European shags (Phalacrocorax aristotelis) using two in situ measures (endoscopy of live birds and necropsy of birds that died naturally) and one non-invasive proxy measure (fecal egg counts (FECs)). In situ methods revealed that almost all chicks were infected (98%), that infections established at an early age and that older chicks hosted more worms, but FECs underestimated prevalence. We found no strong evidence that burdens differed with host sex, rank or hatch date. Heavier chicks had higher burdens, demonstrating that the relationship between burdens and their costs is not straightforward. In situ measures of infection are therefore a valuable tool in building our understanding of the role that parasites play in the dynamics of structured natural populations.
To describe adolescents’ eating patterns of traditional, global/non-local and mixed foods, and the factors that may influence food consumption, access and preferences, in a globalizing city.
A representative sample of school-going adolescents completed a cross-sectional survey including an FFQ designed to identify traditional and global foods. Student’s t test and ordinal logistic regression were used to examine weekly food intake, including differences between boys and girls and between adolescents attending private and public schools.
Vijayapura city, Karnataka State, India.
Adolescents (n 399) aged 13–16 years.
Compared with dietary guidelines, adolescents consumed fruit, green leafy vegetables, non-green leafy vegetables and dairy less frequently than recommended and consumed energy-dense foods more frequently than recommended. Traditional but expensive foods (fruits, dairy, homemade sweets and added fat) were more frequently consumed by private-school students, generally from wealthier, more connected families, than by public-school students; the latter more frequently consumed both traditional (tea, coffee, eggs) and mixed foods (snack and street foods; P≤0·05). Girls reported more frequent consumption of global/non-local packaged and ready-to-eat foods, non-green leafy vegetables and added fat than boys (P≤0·05). Boys reported more frequent consumption of eggs and street foods than girls (P≤0·05).
Adolescents’ eating patterns in a globalizing city reflect a combination of global/non-local and traditional foods, access and preferences. As global foods continue to appear in low- and middle-income countries, understanding dietary patterns and preferences can inform efforts to promote diversity and healthfulness of foods.
We present the first measurement of the anisotropy parameter β using 3D kinematic information outside of the solar neighborhood. Our sample consists of 13 Milky Way halo stars with measured proper motions and radial velocities in the line of sight of M31. Proper motions were measured using deep, multi-epoch HST imaging, and radial velocities were measured from Keck II/DEIMOS spectra. We measure β = −0.3−0.9+0.4, which is consistent with isotropy, and inconsistent with measurements in the solar neighborhood. We suggest that this may be the kinematic signature of a relatively early, massive accretion event, or perhaps several such events.
The intensity ratios of HCO+/HCN and HNC/HCN (1-0) reveal the relative influence of star formation and active galactic nuclei (AGN) or black holes on the circum-nuclear gas of a galaxy, allowing the identification of X-ray dominated regions (XDRs) and Photon-dominated regions (PDRs). It is not always clear in the literature how this intensity ratio calculation has been, or should be performed. This paper discusses ratio calculation methods for interferometric data.