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Oscillations jn "d" vs. sin2ψ plots are due to the inhomogeneous partitioning of strains within the diffracting volume. In polycrystalline specimens, such inhomogeneity can be caused by the elastic incompatibility of neighboring grains or by the inhoniogeneous partitioning of plastic deformation within the diffracting volume. There is, however, little work on the degree of inhomogeneity required to cause a given oscillation, and the relative contribution from the elastic and plastic deformation components to a given oscillation.
Recent studies indicate that, if the stress/strain field within the irradiated volume in an x-ray stress determination experiment is inhomogeneous, oscillations occur in the interplanar spacing vs. sin2ψ plots. There is, however, little work on the degree of inhomogeneity required to cause a given oscillation, the uniqueness of the stress fields that can cause a given set of oscillations, or the error caused by applying the traditional methods currently in use to oscillatory data.
In this paper, numerical modeling and eiasto-plastic finite element analysis was used to determine the strain fields in the diffracting volume of a polycrystalline sample under load. The elastic strain fields obtained from the analysis were then averaged over the regions that would diffract in an x-ray experiment/and then correlated to x-ray strain data to obtain an idea of the problems described ahove.
The results of an experimental study on residual stresses within the encapsulation layers of electronic components are described. For this study, silicon wafers were coated with a flexibilized cycloaliphatic formulation filled with 30 and 40 (vol.) % of Cu particles. The residual stresses were determined by measuring the radii of curvature of the encapsulated wafers. The stress in the Cu particles at the surface was also measured by X-Ray diffraction. It was seen that the stresses within the structure are primarily macro-stresses, with little stress present within the Cu particles. Comparison of the experimental values to those calculated from linear elasticity theory also indicate relaxation within the composite during curing.
In this paper, we derive geometric and analytic properties of invariant sets, including orbit closures, of a large class of piecewise-affine maps
. We assume that (i)
consists of finitely many affine maps defined on a Borel measurable partition of
, (ii) there is a lattice
that contains all of the mutual differences of the translation vectors of these affine maps, and (iii) all of the affine maps have the same linear part that is an automorphism of
. We prove that finite-volume invariant sets of such piecewise-affine maps always consist of translational tiles relative to this lattice, up to some multiplicity. When the partition is Jordan measurable, we show that closures of bounded orbits of
are invariant and yield Jordan measurable tiles, again up to some multiplicity. In the latter case, we show that compact
-invariant sets also consist of Jordan measurable tiles. We then utilize these results to quantify the rate of convergence of ergodic averages for
in the case of bounded single tiles.
To characterise subjective symptoms in patients undergoing surgical repair of superior semicircular canal dehiscence.
Questionnaires assessing symptom severity and impact on function and quality of life were administered to patients before superior semicircular canal dehiscence surgery, between June 2011 and March 2016. Questionnaire sections included general quality of life, internal amplified sounds, dizziness and tinnitus, with scores of 0–100 points.
Twenty-three patients completed the questionnaire before surgery. Section scores (mean±standard deviation) were: 38.2 ± 25.2 for general quality of life, 52.5 ± 23.9 for internal amplified sounds, 35.1 ± 28.8 for dizziness, 33.3 ± 30.7 for tinnitus, and 39.8 ± 22.2 for the composite score. Cronbach's α statistic averaged 0.93 (range, 0.84–0.97) across section scores, and 0.83 for the composite score.
The Gopen–Yang Superior Semicircular Canal Dehiscence Questionnaire provides a holistic, patient-centred characterisation of superior semicircular canal dehiscence symptoms. Internal consistency analysis validated the questionnaire and provided a quantitative framework for further optimisation in the clinical setting.
Lithium-ion batteries featuring electrodes of silicon nanoparticles, conductive carbon, and polymer binders were constructed with electrolyte containing 1.2 M LiPF6 in ethylene carbonate and diethyl carbonate (1:1, w/w). Material binders used include polyvinylidene difluoride (PVdF), polyacrylic acid (PAA), sodium carboxymethyl cellulose (CMC), and a mixture of equal masses of CMC and PAA (CMCPAA). Hard X-ray photoelectron spectroscopy (HAXPES) was performed on the electrodes when fresh, cycled at reduced potential, and cycled one full time to study how substrate material binders affect the early formation of the solid electrolyte interphase (SEI) layer. Electrodes cycled 5, 10, and 20 times were also analyzed to discern what changes to the SEI occur after initial formation. We also present estimates of the SEI thickness by cycle count, indicating that PAA develops the thinnest SEI, followed by CMCPAA, CMC, and PVdF in order of increasing layer thickness.
Synchronisation of the received Pseudorandom (PRN) code and its locally generated replica is fundamental when estimating user position in Global Navigation Satellite System (GNSS) receivers. It has been observed through experiments that user position accuracy decreases if sampling frequency is an integer multiple of the nominal code rate. This paper provides an accuracy analysis based on the number of samples and the residual code phase of each code chip. The outcomes reveal that the distribution of residual code phases in the code phase range [0, 1/ns), where ns is the number of samples per code chip, is the root cause of accuracy degradation, rather than the ratio between sampling frequency and nominal code rate. Doppler frequencies, coherent integration periods, front-end filter bandwidths and received Carrier to Noise ratios (C/N0) also influence receiver accuracy. Also provided are a sampling frequency selection guideline and new proposed estimates of the correlation output and the Delay Locked Loop (DLL) tracking error, which can be applied to precisely model GNSS receiver baseband signal processing.
Central nervous system infections (CNSI) are a leading cause of death and long-term disability in children. Using ICD-10 data from 2005 to 2015 from three central hospitals in Ho Chi Minh City (HCMC), Vietnam, we exploited generalized additive mixed models (GAMM) to examine the spatial-temporal distribution and spatial and climatic risk factors of paediatric CNSI, excluding tuberculous meningitis, in this setting. From 2005 to 2015, there were 9469 cases of paediatric CNSI; 33% were ⩽1 year old at admission and were mainly diagnosed with presumed bacterial CNSI (BI) (79%), the remainder were >1 year old and mainly diagnosed with presumed non-bacterial CNSI (non-BI) (59%). The urban districts of HCMC in proximity to the hospitals as well as some outer districts had the highest incidences of BI and non-BI; BI incidence was higher in the dry season. Monthly BI incidence exhibited a significant decreasing trend over the study. Both BI and non-BI were significantly associated with lags in monthly average temperature, rainfall, and river water level. Our findings add new insights into this important group of infections in Vietnam, and highlight where resources for the prevention and control of paediatric CNSI should be allocated.
We compared the impact of a commercial chlorination product (brand name Air RahMat) in stored drinking water to traditional boiling practices in Indonesia. We conducted a baseline survey of all households with children <5 years in four communities, made 11 subsequent weekly home visits to assess acceptability and use of water treatment methods, measured Escherichia coli concentration in stored water, and determined diarrhoea prevalence among children <5 years. Of 281 households surveyed, boiling (83%) and Air RahMat (7%) were the principal water treatment methods. Multivariable log-binomial regression analyses showed lower risk of E. coli in stored water treated with Air RahMat than boiling (risk ratio (RR) 0·75, 95% confidence interval (CI) 0·56–1·00). The risk of diarrhoea in children <5 years was lower among households using Air RahMat (RR 0·43, 95% CI 0·19–0·97) than boiling, and higher in households with E. coli concentrations of 1–1000 MPN/100 ml (RR 1·54, 95% CI 1·04–2·28) or >1000 MPN/100 ml (RR 1·86, 95% CI 1·09–3·19) in stored water than in households without detectable E. coli. Although results suggested that Air RahMat water treatment was associated with lower E. coli contamination and diarrhoeal rates among children <5 years than water treatment by boiling, Air RahMat use remained low.
We sought to comprehensively assess the prevalence and outcomes of complications associated with Staphylococcus aureus bacteremia (SAB) in children. Secondarily, prevalence of methicillin resistance and outcomes of complications from methicillin-resistant S. aureus (MRSA) vs. methicillin-susceptible S. aureus SAB were assessed. This is a single-center cross-sectional study of 376 patients ⩽18 years old with SAB in 1990–2014. Overall, 197 (52%) patients experienced complications, the most common being osteomyelitis (33%), skin and soft tissue infection (31%), and pneumonia (25%). Patients with complications were older (median 3 vs. 0·7 years, P = 0·05) and more had community-associated SAB (66% vs. 34%, P = 0·001). Fewer patients with complications had a SAB-related emergency department or hospital readmission (10% vs. 19%, P = 0·014). Prevalence of methicillin resistance increased from 1990–1999 to 2000–2009, but decreased in 2010–2014. Complicated MRSA bacteremia resulted in more intensive care unit admissions (66% vs. 47%, P = 0·03) and led to increased likelihood of having ⩾2 foci (58% vs. 26%, P < 0·001). From multivariate analysis, community-associated SAB increased risk and concurrent infections decreased risk of complications (odds ratio (OR) 1·82 (1·1–3·02), P = 0·021) and (OR 0·58 (0·34–0·97), P = 0·038), respectively. In conclusion, children with SAB should be carefully evaluated for complications. Methicillin resistance remains associated with poor outcomes but have decreased in overall prevalence.
The steady, axisymmetric flow induced by a point sink (or source) submerged in an inviscid fluid of infinite depth is computed and the resulting deformation of the free surface is obtained. The effect of surface tension on the free surface is determined and is the new component of this work. The maximum Froude numbers at which steady solutions exist are computed. It is found that the determining factor in reaching the critical flow changes as more surface tension is included. If there is zero or a very small amount of surface tension, the limiting factor appears to be the formation of small wavelets on the free surface; but, as the surface tension increases, this is replaced by a tendency for the lowest point on the free surface to descend sharply as the Froude number is increased.
Establishing an evidence-based diagnostic system informed by the biological (dys)function of the nervous system is a major priority in psychiatry. This objective, however, is often challenged by difficulties in identifying homogeneous clinical populations. Melancholia, a biological and endogenous subtype for major depressive disorder, presents a canonical test case in the search of biological nosology.
We employed a unique combination of naturalistic functional magnetic resonance imaging (fMRI) paradigms – resting state and free viewing of emotionally salient films – to search for neurobiological signatures of depression subtypes. fMRI data were acquired from 57 participants; 17 patients with melancholia, 17 patients with (non-melancholic) major depression and 23 matched healthy controls.
Patients with melancholia showed a prominent loss of functional connectivity in hub regions [including ventral medial prefrontal cortex, anterior cingulate cortex (ACC) and superior temporal gyrus] during natural viewing, and in the posterior cingulate cortex while at rest. Of note, the default mode network showed diminished reactivity to external stimuli in melancholia, which correlated with the severity of anhedonia. Intriguingly, the subgenual ACC, a potential target for treating depression with deep brain stimulation (DBS), showed divergent changes between the two depression subtypes, with increased connectivity in the non-melancholic and decreased connectivity in the melancholic subsets.
These findings reveal neurobiological changes specific to depression subtypes during ecologically valid behavioural conditions, underscoring the critical need to respect differing neurobiological processes underpinning depressive subtypes.
We describe a hybrid pixel array detector (electron microscope pixel array detector, or EMPAD) adapted for use in electron microscope applications, especially as a universal detector for scanning transmission electron microscopy. The 128×128 pixel detector consists of a 500 µm thick silicon diode array bump-bonded pixel-by-pixel to an application-specific integrated circuit. The in-pixel circuitry provides a 1,000,000:1 dynamic range within a single frame, allowing the direct electron beam to be imaged while still maintaining single electron sensitivity. A 1.1 kHz framing rate enables rapid data collection and minimizes sample drift distortions while scanning. By capturing the entire unsaturated diffraction pattern in scanning mode, one can simultaneously capture bright field, dark field, and phase contrast information, as well as being able to analyze the full scattering distribution, allowing true center of mass imaging. The scattering is recorded on an absolute scale, so that information such as local sample thickness can be directly determined. This paper describes the detector architecture, data acquisition system, and preliminary results from experiments with 80–200 keV electron beams.
The Vibrio cholerae O1 (VCO1) El Tor biotype appeared during the seventh cholera pandemic starting in 1961, and new variants of this biotype have been identified since the early 1990s. This pandemic has affected Vietnam, and a large outbreak was reported in southern Vietnam in 2010. Pulsed-field gel electrophoresis (PFGE) and multilocus variable-number tandem-repeat analyses (MLVA) were used to screen 34 VCO1 isolates from the southern Vietnam 2010 outbreak (23 patients, five contact persons, and six environmental isolates) to determine if it was genetically distinct from 18 isolates from outbreaks in southern Vietnam from 1999 to 2004, and two isolates from northern Vietnam (2008). Twenty-seven MLVA types and seven PFGE patterns were identified. Both analyses showed that the 2008 and 2010 isolates were distinctly clustered and separated from the 1999–2004 isolates.
Due to its wide band-gap, Al2O3 is known to have a moderate leakage current and a good dielectric strength . Moreover, this dielectric has a fair permittivity and so constitutes interesting candidate as dielectric for Metal-Insulator-Metal (MIM) capacitor. Atomic Layer Deposition (ALD) allows obtaining a dense and thin Al2O3 amorphous layer. ALD limits problems of interlayer diffusion because Al2O3 is deposited underneath 400°C  which is essential when MIM are co-integrated with temperature sensitive structures.
The aim of our investigation is to attempt to tie aluminum oxide properties dielectric with reliability from the help of capacitors of the entire wafer. In this way, conduction mechanism analysis and capacitance measurements were statistically led on the wafer. We particularly focus our study on the quantification of defects and their influence on the leakage current in planar capacitor. Firstly, to estimate the fixed oxide charges densities in the bulk of Al2O3 and to analyze conduction mechanism, Metal-Oxide-Semiconductor (MOS) (Al/Al2O3/HR-Si) is developed. Then, a MIM stack (Al/TiN/Al2O3/TiN/HR-Si) is developed in order to evaluate the leakage current and the electrical reliability of thin films Al2O3 based MIM capacitors. Different performances are observed according to the area on the wafer. That could be explained by the quality of the Al2O3 layer and the interfaces between TiN and the oxide.
This study examined the temporal and spatial patterns of diarrhoea in relation to hydro-meteorological factors in the Mekong Delta area in Vietnam. A time-series design was applied to examine the temporal pattern of the climate–diarrhoea relationship using Poisson regression models. Spatial analysis was applied to examine the spatial clusters of diarrhoea using Global Moran's I and local indicators of spatial autocorrelation (LISA). The temporal pattern showed that the highest peak of diarrhoea was from weeks 30–42 corresponding to August–October annually. A 1 cm increase in river water level at a lag of 1 week was associated with a small [0·07%, 95% confidence interval (CI) 0·01–0·1] increase in the diarrhoeal rate. A 1 °C increase in temperature at lag of 2 and 4 weeks was associated with a 1·5% (95% CI 0·3−2·7) and 1·1% (95% CI 0·1−2·3) increase in diarrhoeal risk, respectively. Relative humidity and diarrhoeal risk were in nonlinear relationship. The spatial analysis showed significant clustering of diarrhoea, and the LISA map shows three multi-centred diarrhoeal clusters and three single-centred clusters in the research location. The findings suggest that climatic conditions projected to be associated with climate change have important implication for human health impact in the Mekong Delta region.