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Little is known about methylphenidate (MPH) use and mortality outcomes.
To investigate the association between MPH use and mortality among children with an attention-deficit hyperactivity disorder (ADHD) diagnosis.
This population-based cohort study analysed data from Taiwan's National Health Insurance Research Database (NHIRD). A total of 68 096 children and adolescents aged 4–17 years with an ADHD diagnosis and prescribed MPH between 2000 and 2010 were compared with 68 096 without an MPH prescription, matched on age, gender and year of first ADHD diagnosis. All participants were followed to death, migration, withdrawal from the National Health Insurance programme or 31 December 2013. MPH prescriptions were measured on a yearly basis during the study period, and the association between MPH use and mortality was analysed using a repeated-measures time-dependent Cox regression model. The outcome measures included all-cause, unnatural-cause (including suicide, accident and homicide) and natural-cause mortality, obtained from linkage to the National Mortality Register in Taiwan.
The MPH group had lower unadjusted all-cause, natural-, unnatural- and accident-cause mortality than the comparison group. After controlling for potential confounders, MPH use was associated with a significantly lower all-cause mortality (adjusted hazard ratio AHR = 0.81, 95% CI 0.67–0.98, P = 0.027), delayed use of MPH was associated with higher mortality (AHR = 1.05, 95% CI 1.01–1.09) and longer MPH use was associated with lower mortality (AHR = 0.83, 95% CI 0.70–0.98).
MPH use is associated with a reduced overall mortality in children with ADHD in this cohort study, but unmeasured confounding cannot be excluded absolutely.
It is well-known that attention deficit hyperactivity disorder (ADHD) is associated with changes in the dopaminergic system. However, the relationship between central dopaminergic tone and the blood oxygen level-dependent (BOLD) signal during receipt of rewards and penalties in the corticostriatal pathway in adults with ADHD is unclear.
Single-photon emission computed tomography with [99mTC]TRODAT-1 was used to assess striatal dopamine transporter (DAT) availability. Event-related functional magnetic resonance imaging was conducted on subjects performing the Iowa Gambling Test.
DAT availability was found to be associated with the BOLD response, which was a covariate of monetary loss, in the medial prefrontal cortex (r = 0.55, P = .03), right ventral striatum (r = 0.69, P = .003), and right orbital frontal cortex (r = 0.53, P = .03) in adults with ADHD. However, a similar correlation was not found in the controls.
The results confirmed that dopaminergic tone may play a different role in the penalty-elicited response of adults with ADHD. It is plausible that a lower neuro-threshold accompanied by insensitivity to punishment could be exacerbated by the hypodopaminergic tone in ADHD.
Improvement of environmental cleaning in hospitals has been shown to decrease in-hospital cross transmission of pathogens. Several objective methods, including aerobic colony counts (ACCs), the adenosine triphosphate (ATP) bioluminescence assay, and the fluorescent marker method have been developed to assess cleanliness. However, the standard interpretation of cleanliness using the fluorescent marker method remains uncertain.
To assess the fluorescent marker method as a tool for determining the effectiveness of hospital cleaning.
A prospective survey study.
An academic medical center.
The same 10 high-touch surfaces were tested after each terminal cleaning using (1) the fluorescent marker method, (2) the ATP assay, and (3) the ACC method. Using the fluorescent marker method under study, surfaces were classified as totally clean, partially clean, or not clean. The ACC method was used as the standard for comparison.
According to the fluorescent marker method, of the 830 high-touch surfaces, 321 surfaces (38.7%) were totally clean (TC group), 84 surfaces (10.1%) were partially clean (PC group), and 425 surfaces (51.2%) were not clean (NC group). The TC group had significantly lower ATP and ACC values (mean ± SD, 428.7 ± 1,180.0 relative light units [RLU] and 15.6 ± 77.3 colony forming units [CFU]/100 cm2) than the PC group (1,386.8 ± 2,434.0 RLU and 34.9 ± 87.2 CFU/100 cm2) and the NC group (1,132.9 ± 2,976.1 RLU and 46.8 ± 119.2 CFU/100 cm2).
The fluorescent marker method provided a simple, reliable, and real-time assessment of environmental cleaning in hospitals. Our results indicate that only a surface determined to be totally clean using the fluorescent marker method could be considered clean.
Previous studies have indicated that there is dopamine transporter (DAT) dysregulation and P300 abnormality in adults with attention-deficit hyperactivity disorder (ADHD); however, the correlations among the three have not been fully explored.
A total of 11 adults (9 males and 2 females) with ADHD and 11 age-, sex-, and education-level-matched controls were recruited. We explored differences in DAT availability using single-photon emission computed tomography and P300 wave of event-related potentials between the two groups. The correlation between DAT availability and P300 performance was also examined.
DAT availability in the basal ganglia, caudate nucleus, and putamen was significantly lower in the ADHD group. Adults with ADHD had lower auditory P300 amplitudes at the Pz and Cz sites, as well as longer Fz latency than controls. DAT availability was negatively correlated to P300 latency at Pz and Fz.
Adults with ADHD had both abnormal DAT availability and P300 amplitude, suggesting that ADHD is linked to dysfunction of the central dopaminergic system and poor cognitive processes related to response selection and execution.
The purpose of this study was to investigate the effects of 8-week green tea extract (GTE) supplementation on promoting postexercise muscle glycogen resynthesis and systemic energy substrate utilisation in young college students. A total of eight healthy male participants (age: 22·0 (se 1·0) years, BMI: 24·2 (se 0·7) kg/m2, VO2max: 43·2 (se 2·4) ml/kg per min) participated in this study. GTE (500 mg/d for 8 weeks) was compared with placebo in participants in a double-blind/placebo-controlled and crossover study design with an 8-week washout period. Thereafter, all participants performed a 60-min cycling exercise (75 % VO2max) and consumed a carbohydrate-enriched meal immediately after exercise. Vastus lateralis muscle samples were collected immediately (0 h) and 3 h after exercise, and blood and gaseous samples were collected during the 3-h postexercise recovery period. An 8-week oral GTE supplementation had no effects on further promoting muscle glycogen resynthesis in exercised human skeletal muscle, but the exercise-induced muscle GLUT type 4 (GLUT4) protein content was greater in the GTE supplementation trial (P<0·05). We observed that, during the postexercise recovery period, GTE supplementation elicited an increase in energy reliance on fat oxidation compared with the placebo trial (P<0·05), although there were no differences in blood glucose and insulin responses between the two trials. In summary, 8-week oral GTE supplementation increases postexercise systemic fat oxidation and exercise-induced muscle GLUT4 protein content in response to an acute bout of endurance exercise. However, GTE supplementation has no further benefit on promoting muscle glycogen resynthesis during the postexercise period.
Firms are continually trying to identify innovation sources in order to improve organizational performance, but the identification of such origins is a complex and poorly understood issue, particularly as far as nonprofit firms are concerned. The social and cooperative agrifood arrangement has become one of the main and newest types of nonprofit organization in China since the implementation of the law related to specialized cooperatives, on July 1, 2007. In this research, a conceptual model is proposed to show that the characteristics of innovative sources can determine a firm’s absorptive capacity, which in turn can impact its performance. Therefore, absorptive capacity can be expected to enable the mediation of the relationships of innovative sources with the performance of firms. By means of theoretical analysis and practical investigation, this paper provides an assessment of the use of innovation sources and finds critical factors that may foster competitive and sustainable advantages.
To investigate the reciprocal relationship between unhealthy eating behaviours and depressive symptoms from childhood to adolescence.
Unhealthy eating behaviours were measured by the frequencies of eating foods with excess salt, sugar or fat in the past week. Depressive symptoms in the past two weeks were measured using a seven-item scale. Hierarchical linear growth models were used to analyse longitudinal associations between unhealthy eating behaviours and depressive symptoms. Time-fixed variables (sex, parents’ education level and household monthly income) and time-varying variables (parents’ marital status, family activities, body weight, vegetable or fruit consumption, exercising and smoking) were controlled for.
The Child and Adolescent Behaviors in Long-Term Evolution study, which commenced in 2001 and has annual follow-up.
Students (n 2630) followed from 2nd grade (8 years old in 2002) to 11th grade.
The frequency of unhealthy eating behaviours in the previous year and the difference between the frequency in the previous and successive year were positively associated with the initiation and growth rate of depressive symptoms. Depressive symptoms in the previous year and the difference in depressive symptoms between the previous and successive year were positively associated with the initial state and growth rate of unhealthy eating behaviours.
Our results suggest a reciprocal relationship between depressive symptoms and unhealthy eating behaviours. This relationship should be considered when developing programmes targeting depressive symptoms and unhealthy diet in children and adolescents.
We investigated the electrical properties of the rf-sputtered HfxZn1-xO/ZnO heterostructures. The thermal annealing on ZnO prior to the HfxZn1-xO deposition greatly influences the properties of the heterostructures. A highly conductive interface formed at the interface between HfxZn1-xO and ZnO thin films as the ZnO annealing temperature exceeded 500°C, leading to the apparent decrease of the electrical resistance. The resistance decreased with an increase of either thickness or Hf content of the HfxZn1-xO capping layer. The Hf0.05Zn0.95O/ZnO heterostructure with a 200-nm-thick 600°C-annealed ZnO exhibits a carrier mobility of 14.3 cm2V-1s-1 and a sheet carrier concentration of 1.93×1013 cm-2; the corresponding values for the bare ZnO thin film are 0.47 cm2V-1s-1 and 2.27×1012 cm-2, respectively. Rf-sputtered HfZnO/ZnO heterostructures can potentially be used to increase the carrier mobility of thin-film transistors in large-area electronics.
The present study investigated the current status of fruit and vegetable intake among seniors and assessed the relationship between personal background factors, social psychological factors and environmental factors of the study participants and their fruit and vegetable consumption behaviour.
Research data were collected through individual interviews using a questionnaire developed by the authors. SPSS for Windows 15·0 statistical software was used to process and analyse the data.
Elderly individuals sampled from all twenty-nine administration units of Keelung City’s Renai District were interviewed.
Study participants included 398 residents aged 65 years or older.
On average, study participants ate five daily servings of fruits and vegetables on 2·86 d/week. The important variables influencing fruit and vegetable consumption were education level, outcome expectancy, social support, self-efficacy, frequency of dining out and role modelling. Educated participants consumed more fruits and vegetables than those without education. Outcome expectancy, social support, self-efficacy and role modelling had positive impacts on fruit and vegetable intake, but frequency of dining out had a negative impact on fruit and vegetable intake. The significant predictors of fruit and vegetable intake behaviour were education level, outcome expectancy, social support and frequency of dining out. Among those variables, social support was the most influential factor.
Our findings supported the conclusion that health education strategies to increase fruit and vegetable intake among seniors should include the variables of social support and outcome expectancy.
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.
Ink jet technology is applied to the industry application of CPU cooling in this study. The PZT actuated micro-cooling device which generating the micro-scale liquid droplet is used in the CPU cooling of desktop and laptop PCs. It consists the advantages of long lifetime of operation, simple and easily manufactured of the structure with PZT actuator. Since the high latent heat transfer rate, 2260 J/g, of water droplet for the liquid-vapor phase change cooling system, it removes heat from the CPU surface effectively for over 100 W. In order to design an efficient cooling device, it is important to study the PZT material property varies after the laser cutting process and the dimensional effects of PZT actuator on the nozzle plate vibration mode. The frequency and amplitude of the voltage used to energize the PZT transducer are also important parameters that should be properly controlled in order to achieve the optimal liquid breakup conditions. It also reveals the low noise and power consumption in the CPU cooling system with some appropriate operational conditions.
Acrylic triblock (AxMyBz) and diblock (MyBz) oligomers containing methyl methacrylate (MMA, M), methacrylic acid (MAA, A) and dimethylaminoethyl methacrylate (DMAEMA, B) groups are intercalated into the layers of montmorillonite. The results indicate that the block oligomer lay flatly between the clay layers. ICP analyses of Na+ content indicate no unexchanged sodium ions are left in the intercalated clay.
Nanocomposites of epoxy and clay modified with block oligomers were synthesized. Glass transition temperature (Tg) of the nanocomposite is 129.6°C (M18B2424+ modified clay) compared to 84.1°C for the physical mixture of epoxy and unmodified clay. Tg increases with decreasing amount of modified clay. When modified clay content are below 2 phr, Tg higher than 131.7 °C can be obtained. Water resistance and light transmittance of the nanocomposite is also improved over composite of epoxy and unmodified clay.
Small ZrO2 particles were studied by in-situ transmission electron microscopy and the types of events which led to martensitic nucleation were recorded. These metastable particles were single crystals of several hundred nanometers size and were supported on a carbon thin film but were otherwise free from any constraint. At room temperature, they are more than 1200°C below the equilibrium temperature. After dislocation loops were injected in-situ into the originally defect-free particles, a critical loop size was found beyond which the particle transformed spontaneously. It was also observed that Hertzian contacts between two particles led to martensitic nucleation and spontaneous transformation. These results were satisfactorily rationalized by ab-initio theoretical analysis.
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