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Sierra Leone is the country with highest maternal mortality and infections are the underlying cause in 11% of maternal deaths, but the real burden remains unknown. This study aims to determine the incidence and risk factors of surgical site infection (SSI) post-caesarean section (CS) in women admitted to Princess Christian Maternity Hospital (PCMH) in Freetown, Sierra Leone. A prospective case–control (1:3 ratio) study was implemented from 1 May 2018 to 30 April 2019 and 11 women presenting with suspected or confirmed infection post-CS were screened for inclusion as a case. For each case, three patients undergoing CS on the same day and admitted to the same ward, but not presenting with SSI, were selected as controls. The post-CS infection rate was 10.9%. Two hundred and fifty-four clinically confirmed cases were enrolled and matched with 762 control patients. By multivariable analysis, the risk factors for SSI were: being single (odds ratio (OR) 1.48, 95% confidence interval (CI) 1.36–1.66), low education level (OR 1.68, 95% CI 1.55–1.84), previous CS (OR 1.27, 95% CI 1.10–1.52), presenting with premature membranes rupture (OR 1.49, 95% CI 1.18–1.88), a long decision–incision time (OR 2.08, 95% CI 1.74–2.24) and a high missing post-CS antibiotic doses rate (OR 2.52, 95% CI 2.10–2.85).
Healthcare personnel (HCP) were recruited to provide serum samples, which were tested for antibodies against Ebola or Lassa virus to evaluate for asymptomatic seroconversion.
From 2014 to 2016, 4 patients with Ebola virus disease (EVD) and 1 patient with Lassa fever (LF) were treated in the Serious Communicable Diseases Unit (SCDU) at Emory University Hospital. Strict infection control and clinical biosafety practices were implemented to prevent nosocomial transmission of EVD or LF to HCP.
All personnel who entered the SCDU who were required to measure their temperatures and complete a symptom questionnaire twice daily were eligible.
No employee developed symptomatic EVD or LF. EVD and LF antibody studies were performed on sera samples from 42 HCP. The 6 participants who had received investigational vaccination with a chimpanzee adenovirus type 3 vectored Ebola glycoprotein vaccine had high antibody titers to Ebola glycoprotein, but none had a response to Ebola nucleoprotein or VP40, or a response to LF antigens.
Patients infected with filoviruses and arenaviruses can be managed successfully without causing occupation-related symptomatic or asymptomatic infections. Meticulous attention to infection control and clinical biosafety practices by highly motivated, trained staff is critical to the safe care of patients with an infection from a special pathogen.
Impaired illness awareness or insight into illness (IIA) is a common feature of schizophrenia that contributes to medication nonadherence and poor clinical outcomes. Neuroimaging studies suggest IIA may arise from interhemispheric imbalance in frontoparietal regions, particularly in the posterior parietal area (PPA) and the dorsolateral prefrontal cortex (dlPFC). In this pilot study, we examined the effects of transcranial direct current stimulation (tDCS) on brain regions implicated in IIA.
Eleven patients with schizophrenia with IIA (≥3 PANSS G12) and 10 healthy controls were included. A crossover design was employed where all participants received single-session bi-frontal, bi-parietal, and sham stimulation in random order. For each condition, we measured (i) blood oxygen level-dependent (BOLD) response to an illness awareness task pre- and post-stimulation, (ii) regional cerebral blood-flow (rCBF) prior to and during stimulation, and (iii) changes in illness awareness.
At baseline, patients with schizophrenia showed higher BOLD-response to an illness awareness task in the left-PPA compared to healthy controls. Bi-parietal stimulation reduced the interhemispheric imbalance in the PPA compared to sham stimulation. Relatedly, bi-parietal stimulation increased rCBF beneath the anode (21% increase in the right-PPA), but not beneath the cathode (5.6% increase in the left-PPA). Bi-frontal stimulation did not induce changes in rCBF. We found no changes in illness awareness.
Although single-session tDCS did not improve illness awareness, this pilot study provides mechanistic justification for future investigations to determine if multi-session bi-parietal tDCS can induce sustained changes in brain activity in the PPA in association with improved illness awareness.
The repetitive use of ALS inhibitors for smallflower umbrella sedge (Cyperus difformis L.) control has selected for herbicide-resistant (R) populations that threaten the sustainability of rice (Oryza sativa L.) production and demand alternative control measures be developed. A better understanding of seedling recruitment patterns at the field level is required to optimize the timing and efficacy of control measures. Therefore, a population-based threshold model was developed for optimizing germination prediction in multiple acetolactate synthase (ALS)-R and ALS-susceptible (ALS-S) C. difformis biotypes and applied to field-level emergence predictions. Estimated base temperatures (Tb) ranged from 16.5 to 17.6 C with no clear pattern between biotypes; such values are higher than Tb values of other important rice weeds, as well as for rice. Germination rates increased linearly from 16 to 33.7 C. ALS-R seeds germinate faster due to smaller median thermal times to germination (θT(50)) while also displaying lower germination synchronicity across water potentials. Interestingly, ALS-R biotypes were capable of germinating under lower moisture availability, as indicated by their lower (more negative) base water potential values (Ψb(50)) for seed germination; Ψb(50) values ranged from −0.24 to −1.13 MPa. In-field soil germination measurements found thermal times to emergence varied across three water regimes (daily water, flooded, or saturated). Seedling emergence under the daily water treatment was fastest; however, total seedling density was lower than for the other water regimes. In order to optimize springtime C. difformis seedling emergence, soil moisture should be kept around field capacity, as germination is hindered at lower moisture contents. By predicting when most of the seed population germinates, the thermal-time model can address issues regarding the optimal timing for herbicide applications, thereby allowing for improved C. difformis management in rice fields.
Habitat loss and fragmentation are major threats to biodiversity worldwide, and little is known about their effects on bats in Africa. We investigated effects of forest fragmentation on bat assemblages at Kakamega Forest, western Kenya, examining captures at edge and interior locations in three forest fragments (Buyangu, 3950 ha; Kisere, 400 ha; and Malava, 100 ha) varying in forest area and human-use regimes. Basal area, canopy cover, tree density and intensity of human use were used as predictors of bat abundance and species richness. A total of 3456 mist-net hours and 3168 harp-trap hours resulted in the capture of 4983 bats representing 26 species, eight families and four foraging ensembles (frugivores, forest-interior insectivores, forest-edge insectivores and open-space insectivores). Frugivores were frequently captured at the edges of the larger, better-protected forests, but also in the interior of the smaller, more open fragment. Forest-interior insectivores and narrow-space foragers predominated in the interiors of larger fragments but avoided the smallest one. Forest specialists showed positive associations with forest variables (canopy cover, basal area and tree density), whereas frugivores responded positively to the human-use indicators. On these bases, specialist species appear to be especially vulnerable to forest fragmentation.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.
To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.
Clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, and Klebsiella pneumoniae were obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.
Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.
Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Anomalies in the abundance measurements of short lived radionuclides in meteorites indicate that the protosolar nebulae was irradiated by a large number of energetic particles (E≳ 10 MeV), often called solar cosmic rays. The particle flux of the contemporary Sun cannot explain these anomalies, but, similar to T Tauri stars, the young Sun was more active and probably produced enough high energy particles. However, the stellar particle (SP) flux of young stars is essentially unknown. We model the impact of high-energy ionization sources on the chemistry of the circumstellar environment (disks and envelopes). The model includes X-ray radiative transfer and makes use of particle transport models to calculate the individual molecular hydrogen ionization rates. We study the impact on the chemistry via the ionization tracers HCO+ and N2H+. We argue that spatially resolved observations of those molecules combined with detailed models allow for disentangling the contribution of the individual high-energy ionization sources and to put constraints on the SP flux in young stars.
In the collapsing phase of a molecular cloud, the molecular gas temperature is a key to understand the evolutionary process from a dense molecular cloud to stars. In order to know this, mapping observations in NH3 lines are required. Therefore, we made them based on the FUGIN (FOREST Unbiased Galactic plane Imaging survey with Nobeyama 45m telescope). The 6 maps were observed in NH3 (J,K) = (1,1), (2,2), (3,3) and H2O maser lines and obtained temperature maps; some show temperature gradient in a cloud. Additionally 72 cores were observed. These candidates were called as KAGONMA or KAG objects as abbreviation of KAgoshima Galactic Object survey with Nobeyama 45-M telescope in Ammonia lines. We show the results of two regions in W33 and discuss their astrophysical properties.
The low-mass end of the initial mass function remains poorly understood. In this mass range, very low-mass stars, brown dwarfs, and massive planets are able to form through a variety of physical processes. Here, we study the long-term evolution of disk-fragmented systems around low-mass stars, for the epoch up to 10 Myr (the typical lifetime of an embedded cluster) and up to 10 Gyr (the age of the Milky Way). We carry out N-body simulations to study the decay of disk-fragmented systems and the resulting end products. Our simulations indicate rapid decay and frequent physical collisions during the first 10 Myr. We find that disk fragmentation provides a viable mechanism for explaining hierarchical triple systems, the brown dwarf desert, single and binary brown dwarfs, and very low-mass binary systems in the solar neighbourhood.
We use Gaia (DR1, DR2) stellar proper motions to study the kinematics of OB-associations. The average one-dimensional velocity dispersion inside 18 OB-associations with more than 10 Gaia DR1 stars is σv = 3.9 km s−1. The median virial and stellar masses of OB-associations are equal to 7×105 and 9 × 103 solar masses, respectively. The median star-formation efficiency is ε = 2.1%. We have found the expansion in several OB-associations. Models of the Galaxy with a two-component outer ring R1R2 can reproduce the average residual velocities of OB-associations in the Perseus, Sagittarius and Local System complexes.
Star formation is spatially clustered across a range of environments, from dense stellar clusters to unbound associations. As a result, radiative or dynamical interactions with neighbouring stars disrupt (proto)planetary systems and limit their radii, leaving a lasting impact on their potential habitability. In the solar neighbourhood, we find that the vast majority of stars form in unbound associations, such that the interaction of (proto)planetary systems with neighbouring stars is limited to the densest sub-regions. However, the fraction of star formation occurring in compact clusters was considerably higher in the past, peaking at ∼50% in the young Milky Way at redshift z ∼ 2. These results demonstrate that the large-scale star formation environment affects the demographics of planetary systems and the occupation of the habitable zone. We show that planet formation is governed by multi-scale physics, in which Mpc-scale events such as galaxy mergers affect the AU-scale properties of (proto)planetary systems.
It is thought that protoplanets formed in protoplanetary disks excite the orbital motion of the surrounding planetesimals, and the bow shocks caused by the highly excited planetesimals heat their icy component evaporating into gas. We have performed model calculations to study the evolution of molecular abundances of the evaporated icy component, which suggests sulfur-bearing molecules can be good tracers of icy planetesimal evaporation. Here we report the result of our ALMA observations of sulfur-bearing molecules towards protoplanetary disks. The lines were undetected but the obtained upper limits of the line fluxes and our model calculations give upper limits of the fractional abundances of x(H2S) < 10−11 and x(SO) < 10−10 in the outer disk. These results are consistent with the molecular abundances in comets in our Solar system.
The large-scale magnetic field in the accretion disks of young stars is investigated. Main features of our magnetohydrodynamical (MHD) model of the accretion disks and typical simulation results are presented. We discuss the role of MHD effects, ionization structure, magnetic field geometry and strength of the accretion disks.
The stellar ultraviolet radiation (UVR) has been studied in the last decade and has been found to be an important factor to determine the habitability of planetary surfaces. It is known that UVR can be a constraint for life. However, most of the studies of UVR and habitability have missed some fundamental aspects: i) Accurate estimation of the planetary atmospheric attenuation, ii) The biological inferences used to represent the impact of the stellar UVR on life are theoretical and based on the action spectrum (for DNA or microorganisms) or considering parameters as the “lethal dose” obtained from non-astrobiological experiments. Therefore, the conclusions reached by previous studies about the UVR habitability of planetary bodies may be inaccurate. In this work, we propose how to address these studies in a more accurate way through an interdisciplinary approach that combines astrophysics, microbiology, and photobiology and by the use of specially designed laboratory experiments.
Recent theories on the formation of the Solar System turned the attention to the study of low mass cloud cores in massive star forming regions. The Rosette Molecular Cloud is a well-known star forming area having highly filamentary structure with dense cores covering a wide range of masses. These pre- and protostellar cores were observed by Herschel and key core properties were derived from its data. With the Effelsberg 100m telescope a sample of these cores with masses ranging between 3-40 M⊙ were observed in ammonia inversion lines. In this work we are examining the correlations between these two datasets with the aim of gaining insight of the processes behind the star formation of the region.
We investigate dynamics of slender magnetic flux tubes (MFT) in the accretion disks of young stars. Simulations show that MFT rise from the disk and can accelerate to 20-30 km/s causing periodic outflows. Magnetic field of the disk counteracts the buoyancy, and the MFT oscillate near the disk’s surface with periods of 10-100 days. We demonstrate that rising and oscillating MFT can cause the IR-variability of the accretion disks of young stars.