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Brain structural alterations are frequently observed in probands with attention-deficit/hyperactivity disorder (ADHD). Here we examined the microstructural integrity of 76 white matter tracts among unaffected siblings of patients with ADHD to evaluate the potential familial risk and its association with clinical and neuropsychological manifestations.
The comparison groups included medication-naïve ADHD probands (n = 50), their unaffected siblings (n = 50) and typically developing controls (n = 50, age-and-sex matched with ADHD probands). Whole brain tractography was reconstructed automatically by tract-based analysis of diffusion spectrum imaging (DSI). Microstructural properties of white matter tracts were represented by the values of generalized fractional anisotropy (GFA), fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD).
Compared to the control group, ADHD probands showed higher AD values in the perpendicular fasciculus, superior longitudinal fasciculus I, corticospinal tract, and corpus callosum. The AD values of unaffected siblings were in the intermediate position between those of the ADHD and control groups. These AD values were significantly associated with ADHD symptoms, sustained attention and working memory, for all white matter tracks evaluated except for the perpendicular fasciculus. Higher FA and lower RD values in the right frontostriatal tract connecting ventrolateral prefrontal cortex (FS-VLPFC) were associated with better performance in spatial span only in the unaffected sibling group.
Abnormal AD values of specific white matter tracts among unaffected siblings of ADHD probands suggest the presence of familial risk in this population. The right FS-VLPFC may have a role in preventing the expression of the ADHD-related behavioral phenotype.
To develop a theoretical model explaining the longitudinal changes in the caregiving process for family caregivers of persons with mild cognitive impairment (MCI) in Taiwan.
A longitudinal, grounded theory approach using in-depth face-to-face interviews and an open-ended interview guide. We conducted 42 interviews over a two-year period; each participant was interviewed at least once every six months. All participants were interviewed in their home. The participants total of 13 family caregivers of persons with MCI.
One core theme emerged: “protective preparation.” This reflected the family caregiving process of preparation for a further decline in cognitive function, and protection from the impact of low self-esteem, accidents, and symptoms of comorbidities for the family member with MCI. Protective preparation contained three components: ambivalent normalization, vigilant preparation, and protective management.
Interventions to help family caregivers manage the changes in persons with MCI can reduce caregiver burden. Our findings could provide a knowledge base for use by healthcare providers to develop and implement strategies to reduce caregiver burden for family caregivers of persons with MCI.
To investigate the impact of 1-week ventilator circuit change on ventilator-associated pneumonia and its cost-effectiveness compared with a 2-day change.
An observational cohort study.
A tertiary level neonatal intensive care unit in a university-affiliated teaching hospital in Taiwan.
All neonates in the neonatal intensive care unit receiving invasive intubation for more than 1 week from July 1, 2011, through December 31, 2013.
We investigated the impact of 2 ventilator circuit change regimens, either every 2 days or 7 days, on ventilator-associated pneumonia of our cohort.
Measurements and Main Results
A total of 361 patients were maintained on mechanical ventilators for 13,981 days. The 2 groups did not differ significantly in any demographic characteristics. The rate of ventilator-associated pneumonia was comparable between the 2-day group and the 7-day group (8.2 vs 9.5 per 1,000 ventilator-days, P=.439). The durations of mechanical ventilation and hospital stay, and rates of bloodstream infection and mortality, were also comparable between the 2 groups. Switching from a 2-day to a 7-day change policy would save our neonatal intensive care unit a yearly sum of US $29,350 and 525 working hours.
Decreasing the frequency of ventilator circuit changes from every 2 days to once per week is safe and cost-effective in neonates requiring prolonged intubation for more than 1 week.
Owing to energy conservation of waste heat, Lead telluride, PbTe, based materials have promising good thermoelectric properties around a range of middle temperature (Fig. 1, from 300 to 600°C), due to their high melting point, fine chemical stability, and the high figure of merit Z. The general physical properties and factors affecting the figure of merit have been reviewed. This research is focused on the n-type of PbTe materials and collocated with analysis of densities, hardness, elastic modulus, and thermoelectric properties thermoelectric figure of merit ZT=GS2T/κ (where G is electrical conductivity, S is Seebeck coefficient , T is absolute temperature, and κ is thermal conductivity). Room temperature hardness and Young’s modulus are measured by nano-indentation. In this study, the hot-press compacts under the pressure of 4 ton/cm2 can reach the maximum density about 8.2 g/cm3, and hardness and elastic modulus are 0.6 GPa and 70 GPa, respectively. The figure of merit value (ZT) of PbTe in low temperature (around 340°C) was found about 1 with carrier concentration above 1019 cm−3. These results also indicate that the powder metallurgy parameters provide potentialities for further increase of the high efficiency of energy conversion in PbTe materials.
We study the existence and multiplicity of positive solutions for the Dirichlet problem
where λ > 0, 1 < q < 2, p = 2* = 2N/(N − 2), 0 ε Ω ⊂ ℝN, N ≥ 3, is a bounded domain with smooth boundary ∂Ω and f is a non-negative continuous function on . Assuming that f satisfies some hypothesis, we prove that the equation admits at least three positive solutions for sufficiently small λ.
Microwave afterglow plasma oxidation at a low temperature (600 °C ) and rapid thermal annealing (RTA) were combined to grow high quality ultra-thin dielectrics. This new approach has a low thermal budget. The mid-gap interface state density of oxides pretreated in N2O plasma was decreased to about 5×1010 cm−2eV−1 after rapid thermal annealing at 950 °C.It was found that RTA is very effective for relieving the oxide stress and reducing the interface state density. Nitrogen incorporated in oxides by the N2O plasma pretreatment of the Si surface helped to reduce the interface state density. Microstructures of ultra-thin oxide grown by microwave afterglow oxidation with or without RTA were revealed by extended-X-ray-absorption-finestructure (EXAFS) and X-ray photoelectron spectroscopy (XPS) analysis.
We consider a semilinear elliptic system with both concave—convex nonlinearities and critical growth terms in bounded domains. The existence and multiplicity results of positive solutions are obtained by variational methods.
To evaluate the effect on decrease in blood pressure of modifying risk factors for stroke, such as blood lipid profiles, diet habits and indices of body weight, through a family-based nutrition health education programme among hypertensive patients and pre-hypertensive subjects without taking any antihypertensive drugs.
Design and setting
This was a community-based prospective study. The study population was randomly selected from communities in Taipei; potential subjects were invited by telephone to participate.
After excluding subjects whose blood pressure was normal and those using antihypertensive drugs, there were 390 participants included in the study. Subjects in the intervention group (n 293) received nutrition health education on blood pressure control and stroke-related risk factor modification at each visit. Non-intervention subjects (n 97) only acquired a general education sheet available in clinics. The blood pressure of study subjects was measured at baseline and 6-month follow-up to evaluate the intervention’s effect on decrease in blood pressure.
Significant decreases of 2·0 mmHg and 5·9 mmHg in systolic blood pressure were observed both in pre-hypertensive and hypertensive subjects in the intervention group. Additionally, intervention subjects with improvement of total cholesterol and LDL cholesterol, decrease in indices of body weight and increase in consumption of fruit and vegetables also had significant lowering of blood pressure.
The present study provided evidence that the blood pressure of pre-hypertensive and hypertensive subjects could decrease significantly, without taking antihypertensive drugs, after modifying blood lipid profiles and waist by dietary habits changed through a family-based nutrition heath education programme, resulting in a significant effect on stroke risk reduction.
In this paper, we consider the nonhomogeneous semilinear elliptic equation
where λ ≥ 0, 1 < p < (N + 2)/(N − 2), if N ≥ 3, 1 < p < ∞, if N = 2, h(x) ∈ H−l(ℝN), 0 ≢ h(x) ≥ 0 in ℝN, K(x) is a positive, bounded and continuous function on ℝN. We prove that if K(x) ≥ K∞ > 0 in ℝN, and lim∣x∣⃗∞K(x) = K∞, then there exists a positive constant λ✶ such that (✶)λ has at least two solutions if λ ∈ (0, λ✶) and no solution if λ > λ✶. Furthermore, (✶)λ has a unique solution for λ = λ✶ provided that h(x) satisfies some suitable conditions. We also obtain some further properties and bifurcation results of the solutions of (1.1)λ at λ = λ✶.
YBa2Cu3O7−x (1-2-3) powders and 1-2-3 powders doped with 14 wt. % Ag (AgYBa2Cu3O7−x) were produced using aerosol decomposition of nitrate solutions. Powder produced at T > 900 °C consisted of submicron particles and had Tc ≍ 92 K in magnetic susceptibility measurements. As-produced Ag-doped powder was a composite of nearly phase-pure 1-2-3 and crystalline Ag (by x-ray diffraction) for reactor temperatures between 900 °C and 950 °C, whereas powder produced at T≥ 970 °C contained significant amounts of Y2BaCuO5 which were not found in 1-2-3 synthesis in the absence of Ag. This implied that the melting of Ag (∼960 °C) or the Ag-O eutectic (∼940 °C) promoted decomposition of 1-2-3 during powder synthesis. Dilatometry showed that 1-2-3 and Ag/1-2-3 powders densified rapidly between 800 °C and 875 °C, achieving nearly 90% of theoretical density after heating to 875 °C at 5 °C/min in air. Pellets of the Ag-doped powder were also sintered for 2-60 h at 895 °C in air. Scanning electron and optical microscopy revealed that Ag grains remained fine and uniformly distributed, varying in size from ∼1 μm after 2 h to 3–7 μm after 60 h, while 1-2-3 grains became plate-shaped with thicknesses of 1–5 μm and lengths of 10–30 μm after 60 h. Thus, the use of aerosol Ag /1-2-3 powders allows the use of lower processing temperatures and shorter times to produce dense ceramics with smaller Ag and 1-2-3 grain sizes than can be obtained using solid-state reaction routes.
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