Psychosocial risk factors associated with falls among Chinese community-dwelling older adults in Hong Kong

This study examined the relationship between psychosocial factors and falls among community-dwelling older adults in the Hong Kong Special Administrative Region of China. The study included 1573 adults aged 60 or above who lived at home and who were applying for long-term care services. These participants were part of a large cross-sectional survey carried out between 2003 and 2004 in which they completed the Hong Kong Chinese version of the Resident Assessment Instrument-Home Care (RAI-HC) assessment. Of those persons who were surveyed, 516 (32.8%, 95% CI 30.5% to 35.2%) had fallen in the previous 90 days. Bivariate analyses showed that five psychosocial factors (depressive symptoms, fear of falling, a decline in social activities, the number of hours of informal care support during weekdays and living alone) were significantly associated with falls (. P <. 0.05). Logistic regression analysis showed living alone (odds ratio (OR) = 0.62; 95% CI 0.44 to 0.86) was the only psychosocial factor significantly associated with falls, after adjusting for the known significant factors related to falls. It was also found that more elders who lived with others had environmental hazards than those who lived alone (71.0% vs 29.0%, 2 = 4.80, . P = 0.028). These findings suggested that living with others may not be as safe as we assume. Interventions to increase awareness of home safety and to seek co-operation with family members in falls prevention are recommended. Fall preventive strategies should be educated to family members who are living with frail older adults. On the other hand, Chinese older adults who live alone often receive support from relatives or friends. Social support seems to be crucial to prevent them from falls and this measure is recommended to be continued in the community. © 2010 Blackwell Publishing Ltd.postprin

Development and validation of Chinese Health Literacy Scale for Diabetes

AIMS AND OBJECTIVES: To develop and to test the psychometric properties of the Chinese Health Literacy Scale for Diabetes. BACKGROUND: Patients with diabetes encounter many challenges when making health decisions in their daily lives, as they have access to many different kinds of health information. Health literacy issues are new topics in Chinese society. Without a valid and reliable instrument in Chinese, it is difficult to measure the level of health literacy and promote the concept of health literacy in Chinese societies. DESIGN: A methodological study with a sample of 137 patients with type 2 diabetes aged 65 years or older. METHOD: Chinese Health Literacy Scale for Diabetes was developed with reference to the revised Bloom's taxonomy model. Psychometric tests (content validity, item analysis, construct validity, discriminative ability and test-retest reliability) were conducted. Correlations between Chinese Health Literacy Scale for Diabetes and four relevant measures were tested. Cronbach's alpha and alpha if item deleted were calculated to assess internal consistency. RESULTS: Cronbach's alpha for Chinese Health Literacy Scale for Diabetes and its four subscales (remembering, understanding, applying and analysing) were 0.884, 0.885, 0.667, 0.654 and 0.717, respectively. The Chinese Health Literacy Scale for Diabetes was significantly correlated with the Diabetic Knowledge Scale (r = 0.398, p < 0.001), the Diabetic Management Self-Efficacy Scale (r = 0.257, p < 0.001), the Preschool and Primary Chinese Literacy Scale (r = 0.822, p < 0.001) and the Chinese Value of Learning Scale (r = 0.303, p < 0.001). It took an average of seven minutes to complete this 34-item instrument. CONCLUSION: The findings of this study support the Chinese Health Literacy Scale for Diabetes as a reliable and valid instrument for measuring the health literacy of Chinese patients with diabetes. RELEVANCE TO CLINICAL PRACTICE: We recommend that clinicians use this tool to assess patients' health literacy before conducting any kind of health promotion.postprin

Electrolyte influence on sorption behaviours of Direct Blue 71 dye on ramie fibre

Ramie loose fibre was dyed using Direct Blue 71 dye at 70, 80, 90 and 100°C without and with NaCl electrolyte in order to investigate the distinction of dye sorption behaviours. The results show that the dye exhaustion increases with addition of NaCl and shortens the equilibrium dyeing time. The dye adsorption process of dyeing without and with NaCl followed pseudo second-order kinetics, but the rate constant of sorption is larger for the latter compared to the former

Field emission properties of nano-composite carbon nitride films

A modified cathodic arc technique has been used to deposit carbon nitride thin films directly on n+ Si substrates. Transmission Electron Microscopy showed that clusters of fullerene-like nanoparticles are embedded in the deposited material. Field emission in vacuum from as-grown films starts at an electric field strength of 3.8 V/micron. When the films were etched in an HF:NH4F solution for ten minutes, the threshold field decreased to 2.6 V/micron. The role of the carbon nanoparticles in the field emission process and the influence of the chemical etching treatment are discussed.Comment: 22 pages, 8 figures, submitted to J. Vac. Sc. Techn.

LSMR: An iterative algorithm for sparse least-squares problems

An iterative method LSMR is presented for solving linear systems $Ax=b$ and least-squares problem \min \norm{Ax-b}_2, with $A$ being sparse or a fast linear operator. LSMR is based on the Golub-Kahan bidiagonalization process. It is analytically equivalent to the MINRES method applied to the normal equation A\T Ax = A\T b, so that the quantities \norm{A\T r_k} are monotonically decreasing (where $r_k = b - Ax_k$ is the residual for the current iterate $x_k$). In practice we observe that \norm{r_k} also decreases monotonically. Compared to LSQR, for which only \norm{r_k} is monotonic, it is safer to terminate LSMR early. Improvements for the new iterative method in the presence of extra available memory are also explored.Comment: 21 page

Subcarrier and Power Allocation for the Downlink of Multicarrier NOMA Systems

International audienceThis paper investigates the joint subcarrier and power allocation problem for the downlink of a multi-carrier non-orthogonal multiple access (MC-NOMA) system. A novel three-step resource allocation framework is designed to deal with the sum rate maximization problem. In Step 1, we relax the problem by assuming each of the users can use all subcarriers simultaneously. With this assumption, we prove the convexity of the resultant power control problem and solve it via convex programming tools to get a power vector for each user; In Step 2, we allocate subcarriers to users by a heuristic greedy manner with the obtained power vectors in Step 1; In Step 3, the proposed power control schemes used in Step 1 are applied once more to further improve the system performance with the obtained sub-carrier assignment of Step 2. To solve the maximization problem with fixed subcarrier assignments in both Step 1 and Step 3, a centralized power allocation method based on projected gradient descent algorithm and two distributed power control strategies based respectively on pseudo-gradient algorithm and iterative waterfilling algorithm are investigated. Numerical results show that our proposed three-step resource allocation algorithm could achieve comparable sum rate performance to the existing near-optimal solution with much lower computational complexity and outperforms power controlled OMA scheme. Besides, a tradeoff between user fairness and sum rate performance can be achieved via applying different user power constraint strategies in the proposed algorithm

Downlink Connection Density Maximization for NB-IoT Networks using NOMA with Perfect and Partial CSI

International audienceWe address the issue of maximizing the number of connected devices in a Narrowband Internet of Things (NB-IoT) network using non-orthogonal multiple access (NOMA) in the downlink. We first propose an optimal joint sub-carrier and power allocation strategy assuming perfect channel state information (CSI) called Stratified Device Allocation (SDA), that maximizes the connectivity under data rate, power and bandwidth constraints. Then, we generalize the connectivity maximization problem to the case of partial CSI, where only the distancedependent path-loss component of the channel gain is available at the base station (BS). We introduce a novel framework called the Stochastic Connectivity Optimization (SCO) framework. In this framework, we propose a heuristic improvement to SDA namely SDA with Excess Power (SDA-EP) algorithm for operation under partial CSI. Furthermore, we derive a concave approximation (SCO-CA) algorithm of near-optimal performance to SCO given the same amount of CSI. Through computer simulations, we show that SDA-EP and SCO-CA outperform conventional NOMA and OMA schemes in the presence of partial CSI over a wide range of service scenarios

The Effects of Religious Beliefs on the Working Decisions of Women: Some Evidence from Turkey

This paper examines the decision of Turkish women to participate in the labor force. We administered a original survey questionnaire in 2009 to 518 non-working women. Employing logistic regression, we found that religious belief is a crucial factor that discourages women from participating in the labor market. In particular, the regular performance of religious rituals have the greatest negative effect on labor market participation for educated women, who are the most productive human resource in the economy

Solar energy and daylight on tilt planes under CIE standard skies

The CIE (International Commission on Illuminance) Standard Skies depicts the typical diffuse luminance and radiance distributions over the skydome. However, it can be challenging to interpret the luminance and radiance distribution into the irradiance and illuminance contributions on tilt planes by numerical integrations. This paper proposes a surrogate model that determines the ratio of the diffuse irradiance on an arbitrary tilt plane to that on the unobstructed horizontal plane without the complicated and time-consuming numerical integrations. The model is determined using solar altitude, sky conditions, and the angular distance of the plane (surface normal) and the sun. The proposed model is validated by measurement of the vertical illuminance and irradiance that are taken in 2004 and 2005, and the irradiance on planes of different tilt angles and azimuth directions from February to May in 2015. All measurements were in the 10-minute interval. For vertical planes, the proposed approach gives the ratio of the root mean square errors to the measurement average 1.38% to 2.04% lower than a classical model for irradiance and 3.6% to 4.6% for illuminance, when the Skies can be accurately identified. The model thus accurately interprets the luminance and radiance distributions of the CIE Standard Skies, which can be essential to a fast study for the solar energy potential as well as the thermal and daylight environments under different sky conditions