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High-intensity laser–plasma interactions produce a wide array of energetic particles and beams with promising applications. Unfortunately, the high repetition rate and high average power requirements for many applications are not satisfied by the lasers, optics, targets, and diagnostics currently employed. Here, we aim to address the need for high-repetition-rate targets and optics through the use of liquids. A novel nozzle assembly is used to generate high-velocity, laminar-flowing liquid microjets which are compatible with a low-vacuum environment, generate little to no debris, and exhibit precise positional and dimensional tolerances. Jets, droplets, submicron-thick sheets, and other exotic configurations are characterized with pump–probe shadowgraphy to evaluate their use as targets. To demonstrate a high-repetition-rate, consumable, liquid optical element, we present a plasma mirror created by a submicron-thick liquid sheet. This plasma mirror provides etalon-like anti-reflection properties in the low field of 0.1% and high reflectivity as a plasma, 69%, at a repetition rate of 1 kHz. Practical considerations of fluid compatibility, in-vacuum operation, and estimates of maximum repetition rate are addressed. The targets and optics presented here demonstrate a potential technique for enabling the operation of laser–plasma interactions at high repetition rates.
A system of two coupled nonlinear spectral transport equations is derived for two obliquely interacting narrowband Gaussian random surface wavetrains, slowly varying in space and time. Using these two equations, stability analysis is performed for two initially homogeneous wave spectra, subject to unidirectional perturbations. We observe that the effect of randomness produces a decrease in the growth rate of instability, but it is higher than the growth for a single wavetrain. The growth rate of instability is observed to decrease with the increase in spectral width.
The objective of this study was to assess differences in myocardial systolic and diastolic function and vascular function in children 2−5 years of age born to diabetic as compared to non-diabetic mothers.
This study was a retrospective cohort conducted in 2016 at The Aga Khan University Hospital, Karachi, Pakistan. It included children between 2 and 5 years of age born to mothers with and without exposure to diabetes in utero (n = 68 in each group) and who were appropriate for gestational age. Myocardial morphology and function using echocardiogram and carotid intima media thickness (cIMT) and pulse wave velocity was performed to evaluate cardiac function as well as macrovascular remodelling in these children. Multiple linear regression was used to compare the groups.
There was no significant difference in cardiac morphology, myocardial systolic and diastolic function, and macrovascular assessment between the exposed and unexposed groups of AGA children. Subgroup analysis demonstrated a significantly decreased mitral E/A ratio in children whose mothers were on medications as compared to those on dietary control (median [IQR] = 1.7 [1.6–1.9] and 1.56 [1.4–1.7], respectively, p = 0.02), and a higher cIMT in children whose mothers were on medication as compared to controls (0.48 [0.44–0.52] and 0.46 [0.44–0.50], respectively, p = 0.03).
In utero exposure to uncontrolled maternal diabetes has an effect on the cardiovascular structure and function in children aged 2−5 years. However, future work requires long-term follow-up from fetal to adult life to assess these changes over the life course.
The daily time series Flare Index (FI) data of Northern Hemisphere, Southern Hemisphere and Total Disk for Solar Cycle 21- 23 and 24 up to Dec. 2014 has been pre-processed using a 2nd order exponential smoothing algorithm to remove orthogonal noise. The smoothed data in each case is processed for scaling analysis using Rescaled-Range Analysis as well as Finite Variance Scaling Method in order to search for the Hurst exponent. As the value of H obtained from our analysis lies in between 0 and 1, so it can be said that the signal may behave like Fractional Brownian Motion. Also, it is observed that H is less than 0.5 which indicates the data is anti-persistent in nature and it has a strong negative correlation within the signal. The value of H also indicates the oscillating features of the signal which might have some fundamental periodicities in the Suns atmosphere.
Patient-reported outcomes and epidemiological studies in adults with tetralogy of Fallot are lacking. Recruitment and longitudinal follow-up investigation across institutions is particularly challenging. Objectives of this study were to assess the feasibility of recruiting adult patients with tetralogy of Fallot for a patient-reported outcomes study, describe challenges for recruitment, and create an interactive, online tetralogy of Fallot registry.
Adult patients living with tetralogy of Fallot, aged 18–58 years, at the University of North Carolina were identified using diagnosis code query. A survey was designed to collect demographics, symptoms, history, and birth mother information. Recruitment was attempted by phone (Part I, n=20) or by email (Part II, n=20). Data analysis included thematic grouping of recruitment challenges and descriptive statistics. Feasibility threshold was 75% for recruitment and for data fields completed per patient.
In Part I, 60% (12/20) were successfully contacted and eight (40%) were enrolled. Demographics and birth mother information were obtained for all enrolled patients. In Part II, 70% (14/20) were successfully contacted; 30% (6/20) enrolled and completed all data fields linked to REDCap database; the median time for survey completion was 8 minutes. Half of the patients had cardiac operations/procedures performed at more than one hospital. Automatic electronic data entry from the online survey was uncomplicated.
Although recruitment (54%) fell below our feasibility threshold, enrolled individuals were willing to complete phone or online surveys. Incorrect contact information, privacy concerns, and patient-reported time constraints were challenges for recruitment. Creating an online survey and linked database is technically feasible and efficient for patient-reported outcomes research.
The Yellow Sea region is of high global importance for waterbird populations, but recent systematic bird count data enabling identification of the most important sites are relatively sparse for some areas. Surveys of waterbirds at three sites on the coast of southern Jiangsu Province, China, in 2014 and 2015 produced peak counts of international importance for 24 species, including seven globally threatened and six Near Threatened species. The area is of particular global importance for the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea (peak count across all three study sites: 62 in spring  and 225 in autumn  and ‘Endangered’ Spotted Greenshank Tringa guttifer (peak count across all three study sites: 210 in spring  and 1,110 in autumn ). The southern Jiangsu coast is therefore currently the most important migratory stopover area in the world, in both spring and autumn, for both species. Several serious and acute threats to waterbirds were recorded at these study sites. Paramount is the threat of large-scale land claim which would completely destroy intertidal mudflats of critical importance to waterbirds. Degradation of intertidal mudflat habitats through the spread of invasive Spartina, and mortality of waterbirds by entrapment in nets or deliberate poisoning are also real and present serious threats here. Collisions with, and displacement by, wind turbines and other structures, and industrial chemical pollution may represent additional potential threats. We recommend the rapid establishment of effective protected areas for waterbirds in the study area, maintaining large areas of open intertidal mudflat, and the urgent removal of all serious threats currently faced by waterbirds here.
Poultry can be exposed to different kinds of immunosuppressive agents that impair health and welfare by destroying innate and acquired immunity leading to diminished genetic potential of poultry for efficient production. Immunosuppression is a condition characterised by humoral and cellular immune dysfunction that leads to increased susceptibility to secondary infections and vaccine failure. Immune dysfunction at the humoral level is largely due to change in soluble factors mediated by complement or chemokines for innate immunity or due to alterations in antibodies or cytokines for adaptive immunity. In contrast, immune dysfunctions at cellular levels include alterations in neutrophils, monocyte/macrophage, and natural killer cells for innate immunity or changes in B or T lymphocytes for adaptive immunity. In poultry, stress-induced immunosuppression is manifested by failure in vaccination, and increased morbidity and mortality of flocks. Immunosuppressive agents can have cytolytic effects on lymphocyte populations leading to atrophied and depleted lymphoid organs. Immunosuppression can be due to infectious agents or non-infectious agents or due to a combination of them. At present, several modern cellular and molecular approaches are being used to determine the status of the immune system during stress and disease. Comprehensive methodologies for the evaluation of immunosuppression by combined non-infectious and infectious aetiologies have not found general application. Currently, investigations are being developed in order to detect genetic expression of immunologic mediators and receptors by microarray technology. It is likely that this new technique will initiate the development of new strategies for the control and prevention of immunosuppression in poultry. A long term immunosuppression preventive approach involves genetic selection for resistance to immunosuppressive diseases. In general, intervention approaches for immunosuppressive diseases largely rely on minimising stress, reducing exposure to infectious agents through biosecurity, and increasing immune responses by vaccination against immunosuppressive agents.
Bangladesh is a country with a high burden of micronutrient malnutrition. Stunting affects 41 % of children aged under 5 years. Zn is one of the key micronutrients that is associated with stunting. The present study, as part of the national micronutrient survey 2011–2012, revealed for the first time the nationally representative prevalence of Zn deficiency and determined the associations of the condition. A cross-sectional ‘nationwide’ survey was conducted in pre-school-age children (6–59 months; PSAC) and non-pregnant non-lactating women (15–49 years; NPNLW). Multistage random sampling was done in 150 clusters; fifty in each of the rural, urban and slum strata. Data were analysed on 662 PSAC and 1073 NPNLW. Serum Zn was assayed by atomic absorption spectrophotometry. Zn deficiency was defined as serum Zn of <9·9 and <10·1 µmol/l in PSAC and NPNLW, respectively. The national prevalence of Zn deficiency was 44·6 and 57·3 % in PSAC and NPNLW, respectively. In PSAC, it was 29·5, 48·6 and 51·7 %, respectively, in urban, rural and slum strata. Household expenses (β = 0·13; P = 0·007), Hb (β = 0·10; P = 0·005), intake of animal-source Zn (β = 0·096; P = 0·02) and asset score (β = 0·11; P = 0·03) were positively associated with serum Zn in NPNLW. Residence in an urban area (β = 0·33; P = 0·03) and intake of plant-origin Zn (β = −0·13; P = 0·038) determined higher and lower status of Zn in PSAC, respectively. Zn deficiency was highly prevalent in Bangladesh, and it was principally related to inadequate quality of diet. To improve Zn nutrition, Bangladesh needs to strengthen research and programmes related to Zn biofortification, fortification and phytate-reducing technologies in the food system in the short and medium term. In addition, promotion of animal-source Zn for all is important in the long run.
We present a complete spatial and dynamical study of the poorly populated stellar system ESO65SC03. The radial distribution of the system gives a core and cluster radii of 1.10±0.63 and 5.36±0.24 arcmin, respectively. The SNDP does not show any clear enhancement of the surface stellar number density between the stars of the system and the field regions. We derive the optimum isochrone solution for a particular grid size in the CMD using the statistical cleaning procedure. Using the statistically cleaned CMDs, we find the distance modulus, (m − M)0, and reddening, E(B − V), of the system to be 11.8±0.2 and 0.45 mag, respectively. The mean proper motion of this system is − 5.37±0.81 mas yr−1 and 0.31±0.40 in RA and DEC directions, respectively. The mean proper motion of this system is found to be almost similar to the field region. The mass function for the brighter stars is found to be too high for the system to be an open cluster. These combined results place constraints on whether stellar system ESO65SC03 is a POCR or an Asterism. Our understanding is that the ESO65SC03 is in a stage of POCR by losing their main-sequence stars in the dynamic evolution processes.
We sought to examine the factors associated with bacteraemia and their outcome in children with pneumonia and severe acute malnutrition (SAM). All SAM children of either sex, aged 0–59 months, admitted to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh with radiologically confirmed pneumonia from April 2011 to July 2012 were enrolled (n = 405). Comparison was made between pneumonic SAM children with (cases = 18), and without (controls = 387) bacteraemia. The death rate was significantly higher in cases than controls (28% vs. 8%, P < 0·01). In logistic regression analysis, after adjusting for potential confounders, the SAM children with pneumonia and bacteraemia more often had a history of lack of bacillus Calmette-Guérin (BCG) vaccination (odds ratio 7·39, 95% confidence interval 1·67–32·73, P < 0·01). The results indicate the importance of continuation of BCG vaccination which may provide benefit beyond its primary purpose.
To investigate whether the recommended dietary intake of Ca in anaemic infants compromises the expected Hb response, via home fortification with a new Ca- and Fe-containing Sprinkles™ micronutrient powder (MNP).
A double-blind, randomized controlled, 2-month trial was conducted in Bangladesh. Infants were randomized to one of two MNP intervention groups containing Fe and other micronutrients, with or without Ca. Hb, anthropometrics and dietary intake were measured pre- and post-intervention while family demographics were collected at baseline.
Twenty-six rural villages in the Kaliganj sub-district of Gazipur, Bangladesh.
One hundred infants aged 6–11 months.
A significant increase in Hb (MNP, 13·3 (sd 12·6) g/l v. Ca-MNP, 7·6 (sd 11·6) g/l; P < 0·0001) was noted in infants from both groups. However, infants receiving MNP without Ca had a significantly higher end-point Hb concentration (P = 0·024) and rate of anaemia recovery (P = 0·008). Infants receiving MNP with Ca were more likely to remain anaemic (OR 3·2; 95 % CI 1·4, 7·5). Groups did not differ in dietary intake or demographic and anthropometric indicators.
Although both groups showed significant improvement in Hb status, the nutrient–nutrient interaction between Fe and Ca may have diminished the Hb response in infants receiving the Ca-containing MNP.
Despite a number of risk-factor studies in different countries, the epidemiology of Campylobacter colonization in broilers, particularly spatial dependencies, is still not well understood. A series of analyses (visualization and exploratory) were therefore conducted in order to obtain a better understanding of the spatial and temporal distribution of Campylobacter in the Danish broiler population. In this study, we observed a non-random temporal occurrence of Campylobacter, with high prevalence during summer and low during winter. Significant spatio-temporal clusters were identified in the same areas in the summer months from 2007 to 2009. Range of influence between broiler farms were estimated at distances of 9·6 km and 13·5 km in different years. Identification of areas and time with greater risk indicates variable presence of risk factors with space and time. Implementation of safety measures on farms within high-risk clusters during summer could have an impact in reducing prevalence.
Following the generic strategy of creating core-shell structured nanoparticles reported by our group previously  and exploring its applications, an aerosol route combined with iron carbonyl decomposition was developed to encapsulate strong oxidizer within mild oxidizer particles. This modified method enables the application of hygroscopic nano-energetic materials by stabilizing them within a water-insoluble shell. Fe2O3/I2O5 composite oxidizers have been created. Some of the results obtained from combustion tests show that the composite system significantly outperforms the single metal oxide (Fe2O3) system in both pressurization rate and peak pressure. The time-resolved mass spectrometry shows that a significant amount of O2 and I2 are released from the composite oxidizers. These preliminary results suggest a supplement to the previous strategy of obtaining the core-shell structured composite oxidizers and the method still needs to be further optimized.
In recent years, an increase in usage of methane gas in household and automobile industry has been observed. Detection of methane is always a great cause of concern for safety at home or automobile industries, productions in mines and chemical factories. This paper reports the response characteristics of rf-sputtered SnO2 thin films (90 nm thin) loaded with nanoscale catalytic clusters for detection of methane. Ultrathin (8 nm) metal and metal-oxide catalysts (Pt, Ag, Ni, Pd, Au, NiO, Au2O3) clusters are loaded over the surface SnO2 thin film. The SnO2-Pd cluster structure is found to exhibit an enhanced response (97.2%) for 200 ppm of methane at a relatively low operating temperature (220oC). The enhanced response is shown to be primarily due to the dominant roles played by both Fermi level energy control mechanism and spillover mechanism.
Some opportunities for utilizing gelation of rodlike polymers such as poly(p-phenylenebenzobisthiazole) for the production of new materials are described. Morphological studies concerning gels of poly(γ–benzyl–α,L–glutamate) in the solvents toluene, N,N-dimethylformamide and N,N-dimethylformamide/water are reviewed, newly interpreted and extended. A provisional diagram which maps out the gelling behavior in four distinct regions of concentration and temperature concludes the article.
The structures of SiC/Si3N4 interfaces and Si3N4 matrix grain boundaries in Ceramic Matrix Composites (CMC) were investigated by high resolution electron microscopy. The light element chemistry of the interfaces was analyzed by high spatial resolution (∼3 nm) position resolved EELS in a field emission TEM and by high spatial resolution EDS in a dedicated scanning transmission electron microscope (STEM). High-angle annular dark-field (HAADF) imaging (resolution < 1 nm) technique was used to determine the distribution of yttrium atoms at matrix grain boundaries and at SiC/Si3N4 interfaces. HAADF images suggest that yttrium might diffuse into Si3N4 crystals bounding the interfacial and grain boundary regions.
During an HREM/AEM investigation, two different oxygen sinks were identified for a variety of SiC-ceramics involving different sintering mechanisms: segregation of oxygen to i) internal interfaces, and ii) “excess-carbon” secondary phases consisting of basically turbostratic graphite and an intermediate amorphous Si-C-O phase. Si-C-O glasses and polycarbosilanebased nonstoichiometric SiC materials (Nicalon fibers) are well suited as model systems to evaluate the structure and the stability range of the amorphous Si-C-O phase in SiC-based ceramics.