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The ability of the aorta to buffer blood flow and provide diastolic perfusion (Windkessel function) is a determinant of cardiovascular health. We have reported cardiac dysfunction indicating downstream vascular abnormalities in young adult baboons who were intrauterine growth restricted (IUGR) at birth as a result of moderate maternal nutrient reduction. Using 3 T MRI, we examined IUGR offspring (eight male, eight female; 5.7 years; human equivalent 25 years) and age-matched controls (eight male, eight female; 5.6 years) to quantify distal descending aortic cross-section (AC) and distensibility (AD). ANOVA showed decreased IUGR AC/body surface area (0.9±0.05 cm2/m2v. 1.2±0.06 cm2/m2, M±s.e.m., P<0.005) and AD (1.7±0.2 v. 4.0±0.5×10−3/mmHg, P<0.005) without sex difference or group-sex interaction, suggesting intrinsic vascular pathology and impaired development persisting in adulthood. Future studies should evaluate potential consequences of these changes on coronary perfusion, afterload and blood pressure.
The Megamaser Cosmology Project (MCP) measures the Hubble Constant by determining geometric distances to circumnuclear 22 GHz H2O megamasers in galaxies at low redshift (z < 0.05) but well into the Hubble flow. In combination with the recent, exquisite observations of the Cosmic Microwave Background by WMAP and Planck, these measurements provide a direct test of the standard cosmological model and constrain the equation of state of dark energy. The MCP is a multi-year project that has recently completed observations and is currently working on final analysis. Based on distance measurements to the first four published megamasers in the sample, the MCP currently determines H0 = 69.3 ± 4.2 km s−1 Mpc−1. The project is finalizing analysis for five additional galaxies. When complete, we expect to achieve a ~4% measurement. Given the tension between the Planck prediction of H0 in the context of the standard cosmological model and astrophysical measurements based on standard candles, the MCP provides a critical and independent geometric measurement that does not rely on external calibrations or a distance ladder.
In our attempt to investigate the basic active galactic nucleus (AGN) paradigm requiring a centrally located supermassive black hole (SMBH), a close to Keplerian accretion disk and a jet perpendicular to its plane, we have searched for radio continuum in galaxies with H2O megamasers in their disks. We observed 18 such galaxies with the Very Large Baseline Array in C band (5 GHz, ~2 mas resolution) and we detected 5 galaxies at 8 σ or higher levels. For those sources for which the maser data is available, the positions of masers and those of the 5 GHz radio continuum sources coincide within the uncertainties, and the radio continuum is perpendicular to the maser disk’s orientation within the position angle uncertainties.
Eating disorders (EDs) have long-term physical and mental impacts on those affected. However, few population-based studies have estimated the prevalence of EDs. We aimed to estimate the lifetime and 12-month prevalence rates of EDs using DSM-IV criteria, and to examine differences against the DSM-5 criteria for anorexia.
A nationally representative sample of 10 038 residents in Switzerland was interviewed, and prevalence rates for anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED) were assessed using WHO Composite International Diagnostic Interviews (WHO-CIDI).
The lifetime prevalence rate for any ED was found to be 3.5%. Lifetime prevalence estimates for AN, BN, and/or BED were 1.2%, 2.4%, and 2.4%, respectively, among women and 0.2%, 0.9%, and 0.7%, respectively, among men. Utilizing the DSM-5 criteria, the prevalence of AN in women increased by more than 50%, from 1.2% to 1.9%. Among those meeting the criteria for any ED, only 49.4% of men and 67.9% of women had ever sought professional help about their problems with eating or weight.
The higher prevalence of BN we detected relative to other studies should prompt further monitoring for a possible increasing trend. The female v. male ratios, especially for bulimia and BED, are decreasing. Given that more than half of those affected have never consulted any professional about their problems with eating or weight, routine inquiries about eating and weight by clinicians, school teachers/psychologists, and family members may help those who are at risk, especially among men.
This study had 2 objectives: (1) to describe the epidemiology of catheter-related bloodstream infections (CRBSI) in patients with end-stage renal disease (ESRD) who have no access to scheduled dialysis and (2) to evaluate whether a positive culture of the heparin-lock solution is associated with subsequent development of bacteremia.
Retrospective observational cohort design for objective 1; and prospective cohort design for objective 2.
SETTING AND PARTICIPANTS
The study was conducted in a 770-bed public academic tertiary hospital in Dallas, Texas. The participants were patients with ESRD undergoing scheduled or emergent hemodialysis.
We reviewed the records of 147 patients who received hemodialysis between January 2011 and May 2011 and evaluated the rate of CRBSI in the previous 5 years. For the prospective study, we cultured the catheter heparin-lock solution in 62 consecutive patients between June 2012 and August 2012 and evaluated the incidence of CRBSI at 6 months.
Of the 147 patients on emergent hemodialysis, 125 had a tunneled catheter, with a CRBSI rate of 2.61 per 1,000 catheter days. The predominant organisms were Gram-negative rods (GNR). In the prospective study, we found that the dialysis catheter was colonized more frequently in patients on emergent hemodialysis than in those on scheduled hemodialysis. Colonization with GNR or Staphylococcus aureus was associated with subsequent CRBSI at 6 months follow-up.
Patients undergoing emergent hemodialysis via tunneled catheter are predisposed to Gram-negative CRBSI. Culturing the heparin-lock solution may predict subsequent episodes of CRBSI if it shows colonization with GNR or Staphylococcus aureus. Prevention approaches in this population need to be studied further.
Infect. Control Hosp. Epidemiol. 2016;37(3):301–305
The association between Kawasaki disease (KD) and Attention deficit hyperactivity disorder (ADHD) has rarely been studied. In this study, we investigated the hypothesis that KD may increase the risk of ADHD using a nationwide Taiwanese population-based claims database.
Our study cohort consisted of patients who were diagnosed with KD between January 1997 and December 2005 (N = 651). For a comparison cohort, five age- and gender-matched control patients for every patient in the study cohort were selected using random sampling (N = 3255). The cumulative incidence of ADHD was 3.89/1000 (from 0.05 to 0.85) in this study. All subjects were tracked for 5 years from the date of cohort entry to identify whether or not they had developed ADHD. Cox proportional hazard regression analysis was performed to evaluate 5-year ADHD-free survival rates.
Of all patients, 83 (2.1%) developed ADHD during the 5-year follow-up period, of whom 21 (3.2%) had KD and 62 (1.9%) were in the comparison cohort. The patients with KD seemed to be at an increased risk of developing ADHD (crude hazard ratio (HR): 1.71; 95% confidence interval (CI) = 1.04–2.80; p < 0.05). However, after adjusting for gender, age, asthma, allergic rhinitis, atopic dermatitis and meningitis, the adjusted hazard ratios (AHR) of the ADHD in patients with KD showed no association with the controls (AHR: 1.59; 95% CI = 0.96–2.62; p = 0.07). We also investigated whether or not KD was a gender-dependent risk factor for ADHD, and found that male patients with KD did not have an increased risk of ADHD (AHR: 1.62; 95% CI = 0.96–2.74; p = 0.07) compared with the female patients.
The findings of this population-based study suggest that patients with KD may not have an increased risk of ADHD and whether or not there is an association between KD and ADHD remains uncertain.
We studied the association between drinking water, agriculture and sporadic human campylobacteriosis in one region of British Columbia (BC), Canada. We compared 2992 cases of campylobacteriosis to 4816 cases of other reportable enteric diseases in 2005–2009 using multivariate regression. Cases were geocoded and assigned drinking water source, rural/urban environment and socioeconomic status (SES) according to the location of their residence using geographical information systems analysis methods. The odds of campylobacteriosis compared to enteric disease controls were higher for individuals serviced by private wells than municipal surface water systems (odds ratio 1·4, 95% confidence interval 1·1–1·8). In rural settings, the odds of campylobacteriosis were higher in November (P = 0·014). The odds of campylobacteriosis were higher in individuals aged ⩾15 years, especially in those with higher SES. In this region of BC, campylobacteriosis risk, compared to other enteric diseases, seems to be mediated by vulnerable drinking water sources and rural factors. Consideration should be given to further support well-water users and to further study the microbiological impact of agriculture on water.
The PECVD intrinsic, n+, and p+ a-Si:H thin film deposition processes have been studied by the optical emission spectroscope to monitor the plasma phase chemistry. Process parameters, such as the plasma power, pressure, and gas flow rate, were correlated to SiH*, Hα*, and Hβ* optical intensities. For all films, the deposition rate increases with the increase of the SiH* intensity. For the doped films, the Hα*/SiH* ratio is a critical factor affecting the resistivity. The existence of PH3 or B2H6 in the feed stream enhances the deposition rate. Changes of the free radicals intensities can be used to explain variation of film characteristics under different deposition conditions.
MOS capacitor composed of nc-CdSe embedded ZrHfO high-k gate dielectric stack was fabricated and characterized for nonvolatile memory functions. Detailed material and electrical properties have been investigated. With a large charge trapping capability, this kind of device can trap electrons or holes depending on the polarity and magnitude of the applied gate voltage. For the same stress time, the device trapped more holes than electrons under the same magnitude of gate voltage but different polarity. The negative differential resistance peak was observed at the room temperature due to the Coulomb blockade effect. The charge trapping mechanism was delineated with the constant voltage stress test. After 10 years of storage, about 56% of trapped charges still remain in the device.
The influence of the red and green LED light exposure on the memory function of the nanocrystalline MoOx embedded ZrHfO high-k gate dielectric has been investigated. Since the performance of the device is mainly dependent on the hole trapping and detrapping mechanisms, the light exposure affects the hole generation, transfer, and storage to and in the dielectric structure. Both the charge storage capacity and the leakage current were increased from the light exposure. The Coulomb blockade phenomenon in the leakage current density vs. gate voltage curve disappears under the light exposure condition. The light exposure effect is potentially important for practical application of the device.
This study focuses on nanoindentation creep in polycarbonate (PC) and syndiotactic polystyrene (sPS) throughout the transient and steady-state regions. The viscoelastic Burgers model is used to explain transient creep data, while the power-law creep model is used to interpret steady-state creep data. The Newtonian shear viscosity of the Maxwell element and Young’s modulus of the Kelvin element are greater for the creep period than for the preload period, and an opposite trend is noted in the Newtonian shear viscosity of the Kelvin element and Young’s modulus of the Maxwell element. The fact that the Young’s moduli of Maxwell and Kelvin elements in the creep period are different from those in the preload period implies that a stress-induced mesomorphic structure forms or that crystallization occurs in nanoindentation creep. While the strain rate increases with decreasing preload period, the stress exponent factor is almost the same for all preload periods.
The nanocrystalline molybdenum oxide embedded Zr-doped HfO2 high-k nonvolatile memory device has been fabricated using the one pumpdown sputtering process and a rapid thermal annealing step. The majority embedded molybdenum existed in the MoO3 nanocrystal form but a small amount of metallic molybdenum was also detected. The memory function of this device was based on the hole trapping-and-detrapping mechanism. The embedded nanocrystals retained charges after the breakdown of the high-k stack. The charge storage capacity was influenced by light exposure, especially the wavelength. The silicon/high-k interface was also affected by the exposed light. This study provided an insight of the function of the embedded nanocrystals and the light effects on the device.
Background: The Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-NAB) offers information on the clinical diagnosis of Alzheimer's disease (AD) and gives a profile of cognitive functioning. This study explores the effects of age, education and gender on participants' performance on eight subtests in the Chinese-Cantonese version of the CERAD-NAB.
Methods: The original English version of the CERAD-NAB was translated and content-validated into a Chinese-Cantonese version to suit the Hong Kong Chinese population. The battery was administered to 187 healthy volunteers aged 60 to 94 years. Participants were excluded if they had neurological, medical or psychiatric disorders (including dementia). Stepwise multiple linear regression analyses were performed to assess the relative contribution of the demographic variables to the scores on each subtest.
Results: The Cantonese version of CERAD-NAB was shown to have good content validity and excellent inter-rater reliability. Stepwise multiple regression analyses revealed that performances on seven and four out of eight subtests in the CERAD-NAB were significantly influenced by education level and age, respectively. Age and education had significant effects on participants' performance on many tests. Gender also showed a significant effect on one subtest.
Conclusions: The preliminary data will serve as an initial phase for clinical interpretation of the CERAD-NAB for Cantonese-speaking Chinese elders.
The nanocrystalline ITO embedded Zr-doped HfO2 high-k dielectric thin film has been made into MOS capacitors for nonvolatile memory studies. The devices showed large charge storage densities, large memory windows, and long charge retention times. In this paper, authors investigated the temperature effect on the charge transport and reliability of this kind of device in the range of 25°C to 125°C. The memory window increased with the increase of the temperature. The temperature influenced the trap and detrap of not only the deeply-trapped but also the loosely-trapped charges. The device lost its charge retention capability with the increase of the temperature. The Schottky emission relationship fitted the device in the positive gate voltage region. However, the Frenkel-Poole mechanism was suitable in the negative gate voltage region.
This work presents an enhancement of nonvolatile floating gate memory (NFGM) devices comprised of AgInSbTe (AIST) nanocomposite as the charge-storage trap layer and HfO2 or HfO2/SiO2 as the blocking oxide layer. A significantly large memory window (ΔVFB) shift = 30.7 V and storage charge density = 2.3×1013 cm−2 at ±23V gate voltage sweep were achieved in HfO2/SiO2/AIST sample. Retention time analysis observed a ΔVFB shift about 19.3 V and the charge loss about 13.4% in such a sample under the ±15V gate voltage stress after 104 sec retention time test. Regardless of applied bias direction, the sample containing HfO2/SiO2 layer exhibited the leakage current density as low as 150 nA/cm2 as revealed by the current-voltage (I-V) measurement. This effectively suppresses the electron injection between gate electrode and charge trapping layer and leads to a substantial enhancement of NFGM characteristics.
Outlined here is a technique for sub-wavelength infrared surface imaging
performed using a phase matched optical parametric oscillator laser and an
atomic force microscope as the detection mechanism. The technique uses a
novel surface excitation illumination approach to perform simultaneously
chemical mapping and AFM topography imaging with an image resolution of 200 nm. This method was demonstrated by imaging polystyrene micro-structures.
AgInSbTe (AIST)-SiO2 nanocomposite layer prepared by a one-step sputtering process utilizing target-attachment method was implanted in the nonvolatile floating gate memory (NFGM) devices. Device sample subjected to post annealing at 400°C for 2 min in atmospheric ambient exhibited a significant hysteresis memory window (ΔVFB) shift = 5.91V and charge density = 5.22×12 cm-2 after ±8V voltage sweep. During the retention time test, a ΔVFB shift about 3.50 V and charge loss about 28.4% were observed in the sample after a ±5V voltage stress for 104 sec. Cross-sectional TEM revealed that the nanocomposite layer contains the crystalline AIST nanoparticles with the sizes about 5 to 7 nm embedded in SiO2 matrix. XPS analysis indicated that annealing induces the reduction of antimony oxides to form metallic Sb nanocrystals and suppresses the oxygen defects and charge loss in nanocomposite layer. Analytical results illustrated that the utilization of AIST-SiO2 nanocomposite layer may simplify the preparation of NFGM device with satisfactory electrical properties, implying a promising feasibility of such a nanocomposite layer to NFGM devices.
Materials and electrical properties of the MOS capacitor containing nc-RuO embedded in the high-k ZrHfO dielectric film have been studied. The electron- and hole-trapping capacities and trapping sites in this kind of device were investigated using the constant voltage stress method, the frequency-dependent C-V measurement, and the retention characteristics. The negligible charge trapping phenomenon in the non-embedded device rules out the possibility of any trapping site in the bulk ZrHfO film or at the Si/ZrHfO interface. The electrical characterization result suggests that electrons are trapped in the bulk nc-RuO. However, holes have two possible trapping sites, i.e., in the bulk nc-RuO or at the nc-RuO/ZrHfO interface.
To establish the Fe status of pregnant women and their neonates in the Republic of Seychelles.
A prospective study.
Republic of Seychelles.
Pregnant women were recruited and blood samples taken at enrolment and post-delivery along with cord blood samples. Ferritin and soluble transferrin receptor (sTfR) were measured in maternal (n 220) and cord blood (n 123) samples.
Maternal Fe deficiency (ferritin < 15 ng/ml, sTfR > 28 nmol/l) was present in 6 % of subjects at enrolment and in 20 % at delivery. There was no significant decrease in maternal ferritin. A significant increase in sTfR was observed between enrolment and delivery (P < 0·001). Maternal BMI and use of Fe supplements at 28 weeks’ gestation were associated with improved maternal Fe status at delivery, whereas parity had a negative effect on sTfR and ferritin at delivery.
Fe status of pregnant Seychellois women was, on average, within normal ranges. The incidence of Fe deficiency throughout pregnancy in this population was similar to that in a Westernised population. Increased awareness of the importance of adequate Fe intake during pregnancy, particularly in multiparous women, is warranted.
This work studied the Rayleigh-Bénard convection under the first-order slip boundary conditions in both hydrodynamic and thermal fields. The variation principle was applied to find the critical Rayleigh number of instability. The exteneded relations of the critical Rayleigh number (Rc) and the wavenumber (ac) under partially slip boundary conditions were derived. The numerical results showed that both Rc and ac are decreasing with increasing the Knudsen number. The dependence of Rc on the Knudsen number (K) shows that when K≤10−3, the boundary can be considered as nonslip, while K≥10, it can be considered as free boundaries. The maximum change rate occurs when the Knudsen number is around 0.1, indicating that the system would be affected significantly in that range.