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To investigate a Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak event involving multiple healthcare facilities in Riyadh, Saudi Arabia; to characterize transmission; and to explore infection control implications.
Cases presented in 4 healthcare facilities in Riyadh, Saudi Arabia: a tertiary-care hospital, a specialty pulmonary hospital, an outpatient clinic, and an outpatient dialysis unit.
Contact tracing and testing were performed following reports of cases at 2 hospitals. Laboratory results were confirmed by real-time reverse transcription polymerase chain reaction (rRT-PCR) and/or genome sequencing. We assessed exposures and determined seropositivity among available healthcare personnel (HCP) cases and HCP contacts of cases.
In total, 48 cases were identified, involving patients, HCP, and family members across 2 hospitals, an outpatient clinic, and a dialysis clinic. At each hospital, transmission was linked to a unique index case. Moreover, 4 cases were associated with superspreading events (any interaction where a case patient transmitted to ≥5 subsequent case patients). All 4 of these patients were severely ill, were initially not recognized as MERS-CoV cases, and subsequently died. Genomic sequences clustered separately, suggesting 2 distinct outbreaks. Overall, 4 (24%) of 17 HCP cases and 3 (3%) of 114 HCP contacts of cases were seropositive.
We describe 2 distinct healthcare-associated outbreaks, each initiated by a unique index case and characterized by multiple superspreading events. Delays in recognition and in subsequent implementation of control measures contributed to secondary transmission. Prompt contact tracing, repeated testing, HCP furloughing, and implementation of recommended transmission-based precautions for suspected cases ultimately halted transmission.
Steroids are used in the treatment of acute rheumatic fever with moderate-to-severe carditis. Corticosteroids have several cardiovascular side affects that are more common in adults than in children. Corticosteroid-related bradycardia is a rarely seen side effect. Children with bradycardia following oral corticosteroid use are rarely reported previously. We present a child who developed bradycardia after oral corticosteroid treatment and concurrent Wolff–Parkinson–White pattern.
Background: Surgical resection of arteriovenous malformations (AVMs) in eloquent areas is significantly associated with greater surgical morbidity. We describe a functional approach for surgical treatment of these lesions Methods: A total of 20 patients with AVMs in eloquent areas were surgically treated and retrospectively analyzed. Individualized functional approach, using brain mapping and/or neurophysiological monitoring was performed in each case according to every case specific features and location. Seventeen patients underwent surgery under assleep conditions and 3 -patients underwent awake intraoperative mapping Results: There was no mortality. Four patients had hemorrhagic complications (20%). Ten (50%) presented neurological immediate postoperative worsening. Eight of them achieved complete recovery in follow up and 2 showed a permanent deficit. At 6 months follow up all the patients (100%) had good clinical outcome (mRS less than 2). There were no intraoperative seizures but 5 patients (26.3%) developed postoperative seizures. Fifteen patients (75%) had total AVM resection. Language and/or motor function were identified in all but one patient (95%). Each case required changes in surgical strategy to preserve the motor and/or language functions during surgery. Conclusions: Intraoperative monitoring and brain mapping are valuable and safe for the treatment of eloquent AVMs by indentifying and protecting motor and language function during resection.
Blood eosinophil count is associated with a variety of common complex outcomes in epidemiological observation. The aim of this study was to explore the causal association between determined blood eosinophil count and 20 common complex outcomes (10 metabolic, 6 cardiac, and 4 pulmonary). Through Mendelian randomization, we investigated genetic evidence for the genetically determined eosinophil in association with each outcomes using individual-level LifeLines cohort data (n = 13,301), where a weighted eosinophil genetic risk score comprising five eosinophil associated variants was created. We further examined the associations of the genetically determined eosinophil with those outcomes using summary statistics obtained from genome-wide association study consortia (6 consortia and 14 outcomes). Blood eosinophil count, by a 1-SD genetically increased, was not statistically associated with common complex outcomes in the LifeLines. Using the summary statistics, we showed that a higher genetically determined eosinophil count had a significant association with lower odds of obesity (odds ratio (OR) 0.81, 95% confidence interval (CI) [0.74, 0.89]) but not with the other traits and diseases. To conclude, an elevated eosinophil count is unlikely to be causally associated to higher risk of metabolic, cardiac, and pulmonary outcomes. Further studies with a stronger genetic risk score for eosinophil count may support these results.
The aim was to assess the utility and feasibility of a comprehensive cardiac screening protocol in young athletes before participation in sports. A total of 380 athletes referring before participation in sports, between April, 2014 and April, 2015, were included in this study. The mean age was 12.4 years. A screening protocol has been applied to all, including personal and family history, physical examination, 12-lead electrocardiography, transthoracic echocardiography, 24-hour rhythm Holter analysis, and treadmill exercise test. The most frequent complaints were chest pain in 19 (5%), dyspnoea in 13 (3.4%), and dizziness and fainting in five patients (1.3%) on exercise. There was sudden death and arrhythmia in 41 patients (10.7%) owing to family history. Heart murmur was present in 20 (5.2%) and hypertension in 10 patients (2.6%) on physical examination. The 12-lead electrocardiography was abnormal in 9 patients (2.4%). The findings of transthoracic echocardiography were insignificant in 47 patients (12.3%) and in five patients (1.3%) a haemodynamically important condition was detected. The 24-hour rhythm Holter analysis was abnormal in six patients (1.5%). There were significant ST changes in two patients (0.5%) on treadmill exercise test with normal findings on myocardial perfusion scans. No significant relation was present between findings of screening protocol and transthoracic echocardiography, 24-hour rhythm Holter analysis, or treadmill exercise test results.
Pre-participation screening in young athletes should consist of a targeted personal history, family history, physical examination, and 12-lead electrocardiography. Other tests should be applied only if the screening indicates the presence of a cardiovascular disease.
Inflammation confounds the interpretation of several micronutrient biomarkers resulting in estimates that may not reflect the true burden of deficiency. We aimed to assess and compare the micronutrient status of a cohort of Indonesian infants (n 230) at aged 6, 9 and 12 months by ignoring inflammation (unadjusted) and adjusting four micronutrient biomarkers for inflammation with C-reactive protein (CRP) and α-1-glycoprotein (AGP) using the following methods: (1) arithmetic correction factors with the use of a four-stage inflammation model; and (2) regression modelling. Prevalence of infants with any inflammation (CRP>5 mg/l and/or AGP>1 g/l) was about 25% at each age. Compared with unadjusted values, regression adjustment at 6, 9 and 12 months generated the lowest (P<0·001) geometric mean (GM) for serum ferritin (26·5, 14·7, 10·8 μg/l) and the highest GM for serum retinol-binding protein (0·95, 1·00, 1·01 μmol/l) and Zn (11·8, 11·0, 11·5 μmol/l). As a consequence, at 6, 9 and 12 months regression adjustment yielded the highest prevalence of Fe deficiency (20·3, 37·8, 59·5 %) and the lowest prevalence of vitamin A (26·4,16·6, 17·3 %) and Zn (16·9, 20·6, 11·0 %) deficiency, respectively. For serum Se, irrespective of adjustment, GM were low (regression: 0·73, 0·78, 0·81 μmol/l) with prevalence of deficiency >50 % across all ages. In conclusion, without inflammation adjustment, Fe deficiency was grossly under-estimated and vitamin A and Zn deficiency over-estimated, highlighting the importance of correcting for the influence of such, before implementing programmes to alleviate micronutrient malnutrition. However, further work is needed to validate the proposed approaches with a particular focus on assessing the influence of varying degrees of inflammation (i.e. recurrent acute infections and low-grade chronic inflammation) on each affected nutrient biomarker.
Habrobracon hebetor (Say) is a parasitoid of various Lepidoptera including Helicoverpa armigera (Hübner), a key pest of different crops and vegetables. The development of both H. armigera and H. hebetor were simultaneously evaluated against a wide range of constant temperatures (10, 15, 17.5, 20, 25, 27.5, 30, 35, 37.5 and 40 °C). Helicoverpa armigera completed its development from egg to adult within a temperature range of 17.5–37.5 °C and H. hebetor completed its life cycle from egg to adult within a temperature range of 15–40 °C. Based on the Ikemoto and Takai model the developmental threshold (To) and thermal constant (K) to complete the immature stages, of H. armigera were calculated as 11.6 °C and 513.6 DD, respectively, and 13 °C and 148 DD, respectively, for H. hebetor. Analytis/Briere-2 and Analytis/Briere-1 were adjudged the best non-linear models for prediction of phenology of H. armigera and H. hebetor, respectively and enabled estimation of the optimum (Topt) and maximum temperature (Tmax) for development with values of 34.8, 38.7, 36.3, and 43 °C for host and the parasitoid, respectively. Parasitisation by H. hebetor was maximal at 25 °C but occurred even at 40 °C. This study suggests although high temperature is limiting to insects, our estimates of the upper thermal limits for both species are higher than previously estimated. Some biological control of H. armigera by H. hebetor may persist in tropical areas, even with increasing temperatures due to climate change.
The Eastern Gangetic Plain is among the world's most intensively farmed regions, where rainfed and irrigated agriculture coexist. While the region and especially Bangladesh is a major producer of rice (Oryza sativa L. ssp. indica), there is potential to further develop sustainable rice production systems. Specifically, there is scope to include a replacement crop for the short fallow between rice crops in the dominant cropping pattern of rainfed monsoon rice harvest followed by irrigated spring rice. The aim of the current research was to identify a suitable cool-season legume crop – pea (Pisum sativum L.) or lentil (Lens culinaris Medik. ssp. culinaris) – that could be grown in the brief period between rice crops. The study comprised four crop sequence experiments comparing legume cultivars differing in maturity grown in between both long and short duration rice cultivars. These experiments were done at the Bangladesh Rice Research Institute regional station at Rajshahi over three cropping cycles. This was followed by an evaluation of pea vs. fallow between rice crops on three farmers’ fields in one cropping cycle. Here it is demonstrated that green pod vegetable pea is one of the best options to intensify the rainfed monsoon rice–fallow–spring irrigated rice cropping system, notwithstanding other remunerative rabi cropping options that could displace boro rice. The inclusion of an extra crop, pea as green pod vegetable, increased farm productivity by 1·4-fold over the dominant cropping sequence (rice–fallow–rice) and farm net income by fourfold. The study highlighted the advantages in total system productivity and monetary return of crop intensification with the inclusion of a pea crop between successive rice crops instead of a fallow period.
Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.
Dengue fever is an arthropod-borne viral infection that has become endemic in several parts of India including Delhi. We studied occurrence of co-infection with dengue viruses during an outbreak in New Delhi, India in 2014. For the present study, blood samples collected from symptomatic patients were analysed by RT–PCR. Eighty percent of the samples were positive for dengue virus. The result showed that DENV-1 (77%) was the predominant serotype followed by DENV-2 (60%). Concurrent infection with more than one serotype was identified in 43% of the positive samples. Phylogenetic analysis clustered DENV-1 strains with the American African and DENV-2 strains in Cosmopolitan genotypes. Four common amino-acid mutations were identified in the envelope gene of DENV-1 sequences (F337I, A369T, V380I and L402F) and one common mutation (N390S) in the DENV-2 sequences. Further analysis revealed purifying selection in both the serotypes. A significant number of patients were co-infected with DENV-1 and DENV-2 serotypes. Although we do not have direct evidence to demonstrate co-evolution of these two stereotypes, nonetheless their simultaneous occurrence does indicate that they are favoured by evolutionary forces. An ongoing surveillance and careful analysis of future outbreaks will strengthen the concept of co-evolution or otherwise. Whether the concurrent dengue viral infection is correlated with disease severity in a given population is another aspect to be pursued. This study is envisaged to be useful for future reference in the context of overall epidemiology.
Morphology of the nuclear region of the component NGC 7770 indicates that it has a complicated structure in the B-band, while the V-band shows a double nuclear structure. The brightness and color of the nuclear condensations are given. Detailed photometric analysis of this component including luminosity profiles along major and minor scans as well as position angle and ellipticity curves is obtained. Integration and decomposition of the luminosity profiles are also performed. The color distribution and integrated color are also studied taking into account that the blue color together with the unusual color distribution are characteristics relevant to UV-excess galaxies. The integrated photometric parameters are also given.
The state of interaction between the components of the pair is also investigated. The peculiar features appearing in the isophotal maps, the truncation of the luminosity profile along the side of interaction and the unusual appearance of the structural profiles are discussed and considered as strong evidence for the real state of interaction between the components of the pair. A lower limit of the total orbital mass of the system is found to be Mt=1.36 × 1010 M⊙, and the total mass-to-luminosity ratio is f=0.63 f⊙.
To assess vitamin D status and the influence of risk factors such as skin pigmentation and time spent outdoors on hypovitaminosis D among Guatemalan Kekchi and Garifuna adolescents.
Cross-sectional study, with convenient sampling design. Blood samples, anthropometric and behavioural data were all collected during the dry season. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by RIA.
Communities of Rio Dulce and Livingston, Izabal Province, Caribbean coast of Guatemala, with latitude and longitude of 15°49′N and 88°45′W for Livingston and 15°46′N and 88°49′W for Rio Dulce, respectively.
Eighty-six adolescents, divided evenly by sex and ethnicity, with mean age of 14 years.
Mean (sd) 25(OH)D value was 27·8 (7·2) ng/ml for the total group, with 25·8 (5·9) and 29·8 (7·9) ng/ml, respectively, in Kekchis and Garifunas (P=0·01). Use of vitamin D supplementation, clothing practices and sun protection were not statistically different between groups. Skin area exposed on the day of data collection ranged from 20·0 % minimum to 49·4 % maximum, with mean (sd) exposure of 32·0 (8.5) %. With univariate regression analysis, age (P=0·034), sex (P=0·044), ethnicity (P=0·010), time spent outdoors (P=0·006) and percentage skin area exposed (P=0·001) were predictive. However, multivariate analysis indicated that only sex (P=0·034) and percentage skin area exposed (P=0·044) remained as predictors of 25(OH)D.
Despite residing in an optimal geographic location for sunlight exposure, nearly 65 % of study adolescents were either insufficient or deficient in vitamin D. Correction and long-term prevention of this nutritional problem may be instrumental in avoiding adverse effects in adulthood attributed to low 25(OH)D during adolescence.
This paper concerns with the unsteady MHD flow of a second grade fluid between two parallel walls through porous media induced by rectified sine pulses shear stress. The analytical expressions for the velocity field and the adequate shear stress are determined by means of the Laplace transform technique and Fourier cosine and sine transforms and are written as a sum of steady state and transient solutions. The influence of side walls on the fluid motion, the distance between walls for which the velocity of the fluid in the middle of the channel is negligible, and the required time to reach the steady state are presented by graphical illustrations. As the second grade fluid parameter → 0 the problem reduces to the Newtonian fluids performing the same motion.
This paper demonstrates the application of an integrated rotorcraft multidisciplinary design and optimisation framework, deployed for the purpose of preliminary design and assessment of optimum regenerative powerplant configurations for rotorcraft applications. The proposed approach comprises a wide-range of individual modelling theories applicable to rotorcraft flight dynamics, gas turbine engine performance and weight estimation as well as a physics-based stirred reactor model, for the rapid estimation of various gas turbine gaseous emissions. A single-objective Particle Swarm Optimiser is coupled with the aforementioned rotorcraft design framework. The overall methodology is deployed for the design and optimisation of a reference multipurpose Twin-Engine-Light civil rotorcraft, modelled after the Bo105 helicopter, which employs two Rolls-Royce Allison 250-C20B turboshaft engines. Through the implementation of a single-objective optimisation strategy, notionally based optimum engine design configurations are acquired in terms of engine weight, mission fuel burn and mission gaseous emissions inventory at constant technology level.
The acquired optimum regenerative engine configurations are subsequently deployed for the design of conceptual rotorcraft regenerative engine configurations, targeting improved mission fuel economy, enhanced payload-range capability as well as overall environmental impact, while maintaining the respective rotorcraft airworthiness requirements. The proposed methodology essentially constitutes as an enabler for designing rotorcraft powerplants within realistic, three-dimensional operations and towards realising their associated design trade-offs at mission level.
The addition of a CdMgTe (CMT) layer at the back of a CdTe solar cell should improve its performance by reflecting both photoelectrons and forward-current electrons away from the rear surface. Higher collection of photoelectrons will increase the cell’s current, and reduction of forward current will increase its voltage. To achieve electron reflection, conformal CMT layers were deposited at the back of CdTe cells, and a variety of measurements including performance curves, transmission electron microscopy, x-ray photoelectron spectroscopy, and energy-dispersive x-ray spectroscopy were performed. Oxidation of magnesium in the CMT layer was addressed by adding a CdTe capping layer. MgCl2 passivation was substituted for CdCl2 in some cases, but little difference was seen.
The cropping systems of the Eastern Gangetic Plains of Bangladesh, India and Nepal are based on rice. There is a scope to intensify such systems through diversification with lentil, the most popular food legume. Two strategies were evaluated to fit lentil into the short fallow between successive monsoonal (i.e., T. aman) and pre-monsoonal (aus) or irrigated rice (boro) crop. These were early-flowering sole-cropped lentil and relay-sown lentil into rice. Firstly, 18 early-flowering lentil lines at three contrasting sowing dates were tested over two seasons on a research station at Ishurdi in Bangladesh. Secondly, relay sowing was evaluated at the same location with six early-flowering lines and two control cultivars in two seasons. It was also assessed on ten farms in Western Bangladesh, comparing relay with sole cropping over 3 years. Flowering in the early-flowering lentil lines was consistently 9–17 days earlier, than the control cultivars, but they did not achieve an economic yield (<1·0 t/ha). Relay sowing with an existing cultivar produced an economic yield of lentil, which was comparable or higher than sole-cropped lentil in all situations. The relay-sown lentil matured in sufficient time to allow the land to be prepared for the succeeding rain-fed rice crop. It was concluded that the substitution of relay-sown lentil for fallow in the monsoonal rice–fallow–rain-fed rice cropping pattern is a useful option to intensify and diversify cropping in the Eastern Gangetic Plain.
This paper aims to present an integrated multidisciplinary simulation framework, deployed for the comprehensive assessment of combined helicopter–powerplant systems at mission level. Analytical evaluations of existing and conceptual regenerative engine designs are carried out in terms of operational performance and environmental impact. The proposed methodology comprises a wide-range of individual modeling theories applicable to helicopter flight dynamics, gas turbine engine performance as well as a novel, physics-based, stirred reactor model for the rapid estimation of various helicopter emissions species. The overall methodology has been deployed to conduct a preliminary trade-off study for a reference simple cycle and conceptual regenerative twin-engine light helicopter, modeled after the Airbus Helicopters Bo105 configuration, simulated under the representative mission scenarios. Extensive comparisons are carried out and presented for the aforementioned helicopters at both engine and mission level, along with general flight performance charts including the payload-range diagram. The acquired results from the design trade-off study suggest that the conceptual regenerative helicopter can offer significant improvement in the payload-range capability, while simultaneously maintaining the required airworthiness requirements. Furthermore, it has been quantified through the implementation of a representative case study that, while the regenerative configuration can enhance the mission range and payload capabilities of the helicopter, it may have a detrimental effect on the mission emissions inventory, specifically for NOx(Nitrogen Oxides). This may impose a trade-off between the fuel economy and environmental performance of the helicopter. The proposed methodology can effectively be regarded as an enabling technology for the comprehensive assessment of conventional and conceptual helicopter-powerplant systems, in terms of operational performance and environmental impact as well as towards the quantification of their associated trade-offs at mission level.