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Bacillary dysentery continues to be a major health issue in developing countries and ambient temperature is a possible environmental determinant. However, evidence about the risk of bacillary dysentery attributable to ambient temperature under climate change scenarios is scarce. We examined the attributable fraction (AF) of temperature-related bacillary dysentery in urban and rural Hefei, China during 2006–2012 and projected its shifting pattern under climate change scenarios using a distributed lag non-linear model. The risk of bacillary dysentery increased with the temperature rise above a threshold (18·4 °C), and the temperature effects appeared to be acute. The proportion of bacillary dysentery attributable to hot temperatures was 18·74% (95 empirical confidence interval (eCI): 8·36–27·44%). Apparent difference of AF was observed between urban and rural areas, with AF varying from 26·87% (95% eCI 16·21–36·68%) in urban area to −1·90% (95 eCI −25·03 to 16·05%) in rural area. Under the climate change scenarios alone (1–4 °C rise), the AF from extreme hot temperatures (>31·2 °C) would rise greatly accompanied by the relatively stable AF from moderate hot temperatures (18·4–31·2 °C). If climate change proceeds, urban area may be more likely to suffer from rapidly increasing burden of disease from extreme hot temperatures in the absence of effective mitigation and adaptation strategies.
Complex oxides and semiconductors exhibit distinct yet complementary properties owing to their respective ionic and covalent natures. By electrically coupling complex oxides to traditional semiconductors within epitaxial heterostructures, enhanced or novel functionalities beyond those of the constituent materials can potentially be realized. Essential to electrically coupling complex oxides to semiconductors is control of the physical structure of the epitaxially grown oxide, as well as the electronic structure of the interface. Here we discuss how composition of the perovskite A- and B-site cations can be manipulated to control the physical and electronic structure of semiconductor—complex oxide heterostructures. Two prototypical heterostructures, Ba1−xSrxTiO3/Ge and SrZrxTi1−xO3/Ge, will be discussed. In the case of Ba1−xSrxTiO3/Ge, we discuss how strain can be engineered through A-site composition to enable the re-orientable ferroelectric polarization of the former to be coupled to carriers in the semiconductor. In the case of SrZrxTi1−xO3/Ge we discuss how B-site composition can be exploited to control the band offset at the interface. Analogous to heterojunctions between compound semiconducting materials, control of band offsets, i.e., band-gap engineering, provides a pathway to electrically couple complex oxides to semiconductors to realize a host of functionalities.
Presently, physical limitations are restricting the development of the microelectronic industry driven by Moore's law. To achieve high-performance, small form factor, and lightweight applications, new electronic packaging methods have exceeded Moore's law. This research proposes a double-chip stacking structure in an embedded fan-out wafer-level packaging with double-sided interconnections. The overall reliability of the solder joints and redistributed lines is assessed through finite element analysis. The application of soft lamination material and selection of a carrier material whose coefficient of thermal expansion (CTE) is close to that of the printed circuit board can effectively enhance the reliability of solder joints over more than 1,000 cycles. A trace/pad junction whose direction is parallel to the major direction of the CTE mismatch is recommended, and the curved portion of trace lines can absorb the expansion of metal lines and filler material. Design-on-simulation methodology is necessary to develop novel packaging structures in the electronic packaging industry.
A nationwide population-based cohort was used to examine the severity of liver cirrhosis and risk of mortality from oral cancer.
The cohort consisted of 3583 patients with oral cancer treated by surgery between 2008 and 2011 in Taiwan. They were grouped on the basis of normal liver function (n = 3471), cirrhosis without decompensation (n = 72) and cirrhosis with decompensation (n = 40). The primary endpoint was mortality. Hazard ratios of death were also determined.
The mortality rates in the respective groups were 14.8 per cent, 20.8 per cent and 37.5 per cent at one year (p < 0.001). The adjusted hazard ratios of death at one year for each group compared to the normal group were 2.01 (p = 0.021) for cirrhotic patients without decompensation, 4.84 (p < 0.001) for those with decompensation and 2.65 (p < 0.001) for those receiving chemotherapy.
Liver cirrhosis can be used to predict one-year mortality in oral cancer patients. Chemotherapy should be used with caution and underlying co-morbidities should be managed in cirrhotic patients to reduce mortality risk.
Enterotoxigenic Escherichia coli (ETEC) is a type of pathogenic bacteria that cause diarrhea in piglets through colonizing pig small intestine epithelial cells by their surface fimbriae. Different fimbriae type of ETEC including F4, F18, K99 and F41 have been isolated from diarrheal pigs. In this study, we performed a genome-wide association study to map the loci associated with the susceptibility of pigs to ETEC F41 using 39454 single nucleotide polymorphisms (SNPs) in 667 F2 pigs from a White Duroc×Erhualian F2 cross. The most significant SNP (ALGA0022658, P=5.59×10−13) located at 6.95 Mb on chromosome 4. ALGA0022658 was in high linkage disequilibrium (r2>0.5) with surrounding SNPs that span a 1.21 Mb interval. Within this 1.21 Mb region, we investigated ZFAT as a positional candidate gene. We re-sequenced cDNA of ZFAT in four pigs with different susceptibility phenotypes, and identified seven coding variants. We genotyped these seven variants in 287 unrelated pigs from 15 diverse breeds that were measured with ETEC F41 susceptibility phenotype. Five variants showed nominal significant association (P<0.05) with ETEC F41 susceptibility phenotype in International commercial pigs. This study provided refined region associated with susceptibility of pigs to ETEC F41 than that reported previously. Further works are needed to uncover the underlying causal mutation(s).
Three-dimensional integrated circuit packages with through-silicon vias (TSVs) provide a good solution to the integration of different chips and help achieve high performance. The signals are transmitted to different layers directly through the vias, thereby enabling the high performance of the chips. Plasma-enhanced chemical vapor-deposited SiO2, polyimide, and benzo-cyclo-butene are commonly used as the passivation layer for three-dimensional packages. In the 3D stacked chips, mismatch of the coefficient of thermal expansion between the passivation material and silicon will generate thermal/mechanical stress in the metal trace and the stress affects the behavior of electromigration. However, few studies have examined the relationship among the external mechanical stress and critical product of electromigration. In the present study, external stress is applied to the aluminum thin film by a four-point bending equipment. In order to apply higher external stress in the aluminum thin film, the fracture strength of the silicon substrate should be improved. Reduces the edge chipping of the test sample is a key factor for improving the fracture strength of the silicon substrate and a special cutting approach is employed to obtain higher silicon strength. A two-step cutting method is applied to reduce front side chipping and also a dicing before grinding approachis adopted to reduce backside chipping, the above-mentioned technology can enable more than 275MPa of external stress on the aluminum thin film and can make the critical length effect more visible. The residual stress of the aluminum thin film is at stress-free state after annealing at 300°C for 10h. The critical product is found to be reduced from 1,294A/cm to 1,281A/cm when 120MPa of mechanical tensile stress is applied. It increased to 1,315A/cm under 120MPa of mechanical compressive stress. Clearly, electromigration behavior is enhanced by tensile stress and decreased by compressive stress. In the current research, a modified equation for Blech condition is proposed with a stress-dependent effective charge number, the effective charge number increased when tensile stress was applied and decreased when compressive stress was applied.
With prevention and treatment of mental disorders a challenge for primary care and increasing capability of electronic medical records (EMRs) to facilitate research in practice, we aim to determine the prevalence and treatment of mental disorders by using routinely collected clinical data contained in EMRs.
We reviewed EMRs of patients randomly sampled from seven general practices, by piloting a study instrument and extracting data on mental disorders and their treatment.
Data were collected on 690 patients (age range 18–95, 52% male, 52% GMS-eligible). A mental disorder (most commonly anxiety/stress, depression and problem alcohol use) was recorded in the clinical records of 139 (20%) during the 2-year study period. While most patients with the common disorders had been prescribed medication (i.e. antidepressants or benzodiazepines), a minority had been referred to other agencies or received psychological interventions. ‘Free text’ consultation notes and ‘prescriptions’ were how most patients with disorders were identified. Diagnostic coding alone would have failed to identify 92% of patients with a disorder.
Although mental disorders are common in general practice, this study suggests their formal diagnosis, disease coding and access to psychological treatments are priorities for future research efforts.
Chitotriosidase, secreted by activated macrophages, is a biomarker of activated macrophages. In this study, we explored whether chitotriosidase could be adopted as a biomarker to evaluate the curative effect on tuberculosis (TB). Five counties were randomly selected out of 122 counties/cities/districts in Hunan Province, China. Our cases were all TB patients who were newly diagnosed or had been receiving treatment at the Centers for Disease Control (CDCs) of these five counties between April and August in 2009. Healthy controls were selected from a community health facility in the Kaifu district of Changsha City after frequency-matching of gender and age with the cases. Chitotriosidase activity was evaluated by a fluorometric assay. Categorical variables were analysed with the χ2 test. Measurement data in multiple groups were tested with analysis of variance and least significant difference (LSD). Correlation between chitotriosidase activity and the degree of radiological extent (DRE) was examined by Spearman's rank correlation test. The average chitotriosidase activity levels of new TB cases, TB cases with different periods of treatment (<3, 3–6, >6 months) and the control group were 54·47, 34·77, 21·54, 12·73 and 10·53 nmol/h.ml, respectively. Chitotriosidase activity in TB patients declined along with the continuity of treatment. The chitotriosidase activity of both smear-positive and the smear-negative pulmonary TB patients decreased after 6 months' treatment to normal levels (P < 0·05). Moreover, chitotriosidase activity was positively correlated with DRE (r = 0·607, P < 0·001). Our results indicate that chitotriosidase might be a marker of TB treatment effects. However, further follow-up study of TB patients is needed in the future.
Some studies demonstrated that physical activity may have beneficial effect on cognitive function. The objective of the study was to estimate the association between physical activity and cognitive function in community-dwelling elderly Chinese in Hong Kong (HK) and Guangzhou (GZ).
In the neighborhood of HK and GZ, a convenience sample of 557 (260 in HK and 297 in GZ) older persons without dementia aged over 60 years (73.4 ± 6.5) was recruited. Physical activity was measured using a checklist. Information on physical activity participation, cognitive function, and other variables were collected. Multivariate linear regression analyses were performed to evaluate the association between physical activity and cognitive function.
Total number of physical activities showed significant association with the delayed recall test (p < 0.01) and category verbal fluency test (CVFT) (p < 0.01). However, with further adjustment for participation in intellectual activity, the coefficients were no longer statistically significant (p > 0.05)
Physical activity may not be associated with better cognitive function among elderly Chinese independently of other factors.
Most knowledge regarding the effects of antidepressant drugs is at the receptor level, distal from the nervous system effects that mediate their clinical efficacy. Using functional magnetic resonance imaging (fMRI), this study investigated the effects of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on resting-state brain function in patients with major depressive disorder (MDD).
Fourteen first-episode drug-naive MDD patients completed two fMRI scans before and after 8 weeks of escitalopram therapy. Scans were also acquired in 14 matched healthy subjects. Data were analyzed using the regional homogeneity (ReHo) approach.
Compared to controls, MDD patients before treatment demonstrated decreased ReHo in the frontal (right superior frontal gyrus), temporal (left middle and right inferior temporal gyri), parietal (right precuneus) and occipital (left superior occipital gyrus and right cuneus) cortices, and increased ReHo in the left dorsal medial prefrontal gyrus and left anterior lobe of the cerebellum. Compared to the unmedicated state, ReHo in the patients after treatment was decreased in the left dorsal medial prefrontal gyrus, the right insula and the bilateral thalamus, and increased in the right superior frontal gyrus. Compared to controls, patients after treatment displayed a ReHo decrease in the right precuneus and a ReHo increase in the left anterior lobe of the cerebellum.
Successful treatment with escitalopram may be associated with modulation of resting-state brain activity in regions within the fronto-limbic circuit. This study provides new insight into the effects of antidepressants on functional brain systems in MDD.
Network Identification by Deconvolution (NID) method is used to capture the heat cumulative effect in the homodyne configuration of the Pump-Probe Transient Thermoreflectance (PPTTR) experiment. This cumulative effect is very important in the interpretation of the PPTTR which is becoming widely used for the extraction of thin film thermal conductivity. We show that this intrinsic behavior can be introduced as a cumulative effect weight function in the time constant spectrum of the structure under study. We show how the main features of this weight function change when we change the laser repetition rate and/or the laser pump beam modulation frequency, and how these changes may affect the extraction of the thermal properties of the sample under study, particularly the thermal conductivity and the interface thermal resistance. Numerical simulations of the PPTTR experiment are used to validate the application of NID method. Limitations of the method will also be discussed.
We investigated defects in CdZnTe crystals produced from various conditions and their impact on fabricated devices. In this study, we employed transmission and scanning transmission electron microscope (TEM and STEM), because defects at the nano-scale are not observed readily under an optical or infrared microscope, or by most other techniques. Our approach revealed several types of defects in the crystals, such as low-angle boundaries, dislocations and precipitates, which likely are major causes in degrading the electrical properties of CdZnTe devices, and eventually limiting their performance.
We present the studying of oxygen and moisture traps in MEH-PPV through the MIS Capacitance – Voltage (C-V) analysis, and the Attenuated Total Reflection Infrared (ATR IR) spectroscopy technique. The presence of oxygen studied by ATR IR has also been verified by optical images from high resolution optical microscope. In quasi-static C-V measurements of the MIS (Al/MEH-PPV/p-Si) capacitors made, an extension of the weak inversion region was measured before strong inversion, which becomes more pronounced with aging. This increase in the weak inversion region is attributed to electron trapping by oxygen to form negative ions in the MEH-PPV layer. ATR IR spectroscopy shows the formation of carbonyl peak at 1651 cm−1 with aging, which is due to the presence of oxygen. Both the C-V analysis and Attenuated Total Reflection IR Spectroscopy are powerful tools for investigating the degradation of MEH-PPV polymer.
Reactive YBa2Cu3O7-δ powders have been produced via freeze-drying, carbonate- and oxalate-coprecipitating methods. In the coprecipitating methods, sodium carbonate and sodium oxalate were used as precipitants. These powders were characterized by TGA, XRD, and SEM. The morphologies of the YBa2Cu3O7-δ powders produced from these methods are different from each other. The influence of hot-press process on the bulk density, micro-structure development and superconducting properties of YBa2Cu3O7-δ samples was also studied.
Via electrical property measurements (conductivity, thermopower) at 700°C on sinter-forged YBa Cu O, it was YBa2Cu3O7−x, it was determined that conduction occurs via small polaron conduction in the tetragonal phase. From the thermopower and oxygen content the distribution of copper valence states was determined.