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Nb-doped lead zirconate titanate (PZT) films with up to 12 at. % of Nb were co-sputtered from oxide PZT and metallic Nb targets at a substrate temperature of 600 °C. Up to 4 at. % of Nb was doped into the perovskite structure with the formation of B-site cation vacancies for charge compensation. The preferential (111) PZT orientation decreased with Nb-doping within the solid solution region. The ferroelectric response of the films was affected by the large values of the internal field present in the samples (e.g., −84.3 kV cm−1 in 12 at. % Nd doped films). As-deposited unpoled films showed large values of the pyroelectric coefficient due to self-poling. The pyroelectric coefficient increased with Nb-doping and showed a complex dependence on the applied bias. The photovoltaic effect was observed in the films. The value of the photocurrent increased with the A/B ratio. The combined photovoltaic–pyroelectric effect increased the values of the measured current by up to 47% upon light illumination. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate and validate chemical shift imaging (CSI) for in vivo glutamate (Glu) quantification in patients with supratentorial gliomas. If validated, CSI could become an extremely useful tool to investigate metabolic dysfunction of Glu in excitotoxic neuropathologies. Quantitative CSI estimates of Glu concentrations were compared with known concentrations of Glu in aqueous phantom solutions. Forty-one patients with known or likely supratentorial gliomas underwent preoperative CSI. The spectra obtained were analyzed for Glu concentrations and Glu to creatine (Cr) ratios. These in vivo measurements were correlated against ex vivo Glu content quantified by high performance liquid chromatography (HPLC) measured in 65 resected brain tumor and peritumoral brain specimens. For the phantom solutions the CSI estimates of Glu concentration and the Glu/Cr ratios were highly correlated with known Glu concentration ( r2 = 0.95, p = 0.002, and r2 = 0.97, p < 0.0001, respectively). There was a modest, but statistically significant, correlation between the ex vivo measured Glu and in vivo spectroscopic Glu concentration ( r2 = 0.22, p = 0.04) and ratios of Glu to Cr ( r2 = 0.30, p = 0.002). Quantitative measurement of Glu content is feasible in patients with supratentorial gliomas using CSI. The in vitro and in vivo results suggest that this has the potential to be a reliable quantitative imaging assay for brain tumor patients. This may have wide clinical research applications in a number of neurological disorders where Glu excitotoxicity and metabolic dysfunction are known to play a role in pathogenesis, including tumor associated epilepsy, epilepsy, stroke and neurotrauma. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study explores the possible effect of Foreign Direct Investment (FDI) on the economic growth performance in Kenya. The study employs secondary data for regression analysis. The sample consists of annual data covering the period between 1975 and 2008. The growth rate of real gross domestic product per capita is used as a proxy for economic growth. Growth rate of labor, human capital, the ratio of domestic investments to GDP and the ratio of FDI inflows to GDP are independent variables that explain the economic growth in Kenya.The results show that through the human capital channel FDI may be beneficial for growth. The economic growth estimation shows strong complementary effects between FDI and human capital. On the whole, on the economic growth regression does not constitute prima facie evidence against the null hypothesis that FDI inflows do not promote economic growth in Kenya. However, the results suggest that FDI has a positive impact on economic growth through the interaction of human capital. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine trends in disease incidence and recent patterns of hepatitis C virus (HCV) transmission in Canada, using the Enhanced Hepatitis Strain Surveillance System (EHSSS). Demographic, clinical, and potential risk factor information on newly acquired HCV infection, from 1998 to 2004, was collected using standardized questionnaires. During this time period, the reported incidence of newly acquired HCV infection declined by 36.4% from 3.3 cases per 100,000 in 1998, to 2.1 cases per 100,000 in 2004. The disease incidence peaked at 15 to 39 y of age, confirming injecting drug use as the most frequently reported route of transmission. The proportion of cases attributed to health care-acquired HCV infection decreased over this time period. Although the incidence of newly acquired HCV infection in the EHSSS was found to be declining, hepatitis C remains an important public health threat to Canadians. Prevention efforts for HCV should focus on injection drug use, especially for people aged 15 to 39 y. [ABSTRACT FROM AUTHOR]

A major limitation in cancer gene therapy, specifically gene-dependent enzyme prodrug therapy (GDEPT), is inefficient gene delivery and expression. The suicide gene cytosine deaminase (CD) and its substrate, 5-fluorocytosine (5-FC), have been extensively explored due to the inherent ‘bystander’ effect achieved through diffusion of the toxic metabolite 5-fluorouracil (5-FU). In this study, we aimed to enhance this ‘bystander’ effect by fusing the Saccharomyces cerevisiae CD to the HSV-1 tegument protein vp22, a novel translocating protein. Two constructs were created: one with vp22 fused to CD (vp22CD) and a second wherein a truncated vp22, lacking the necessary residues for trafficking, fused to CD (delvp22CD). The generated 9L stable lines exhibited similar growth rates, enzyme expression, CD activity, and sensitivity to 5-FC and 5-FU. However, mixed population colony formation assays demonstrated greater bystander effect with the vp22CD fusion as compared to delvp22CD. This enhancement was maintained in vivo where 9L tumors expressing 20 or 50% vp22CD exhibited increased growth delay compared to the respective delvp22CD tumors. Moreover, adenoviral transduction of established wild-type 9L tumors showed increased growth delay with vp22CD (Ad-EF_vp22CD) as compared to equivalent CD (Ad-EF_CD) transduced tumors. Finally, confirming the increased efficacy, 19F magnetic resonance spectroscopy (MRS) of vp22CD-expressing tumors demonstrated increased 5-FU levels as compared to tumors expressing the nontranslocating CD. These results together demonstrated that fusion of vp22 to CD resulted in CD translocation, which in turn amplified conversion of 5-FC to 5-FU in vivo and enhanced the therapeutic benefit of this GDEPT strategy.Gene Therapy (2006) 13, 127–137. doi:10.1038/sj.gt.3302631; published online 15 September 2005 [ABSTRACT FROM AUTHOR]

We tested an intervention to help smokers abstain (fast) from smoking before surgery, maintain abstinence postoperatively, and achieve long-term cessation. A randomized experiment included 237 patients admitted for presurgical assessment who smoked. The intervention included counseling and nicotine replacement therapy. Treatment group participants (73.0%) were more likely to fast than were controls (53.0%): chi(2)(1, N = 228) = 8.89, p =.003, and more likely to be abstinent 6 months after surgery (31.2% vs. 20.2%). There was no significant difference in the abstinence rates at 12 months after surgery, chi(2)(1, N = 169) <.001, p = 1.00. Encouraging patients to fast from smoking before surgery and postoperative support are efficacious ways to reduce preoperative and immediate post-operative tobacco use. Copyright 2004 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A grounded theory study was undertaken to describe how adolescents make decisions about sunbathing during the transition from childhood to adolescence and to propose an explanation for the relationships among factors affecting the adoption of sun tanning. In-depth interviews (n = 40) were conducted separately with adolescents (aged 12 to 16 years) and their parents. Constant comparative analysis of adolescents' accounts identified two methods that adolescents described as a means of getting a suntan: intentional sun tanning and incidental sun tanning. The process of adolescents' decision-making about getting a suntan can be understood by examining the following sequence: becoming motivated to get a tan, experimenting with sun tanning, and establishing self as an intentional tanner or incidental tanner. Implications for developing strategies to prevent the adoption of sun-tanning habits among adolescents are presented. [ABSTRACT FROM AUTHOR]

The article focuses on the occurrence of failed back syndrome to a patient with intractable back pain and sciatica. The patient will undergo multiple operations such as myelograms if his condition does not improve with numerous courses of physiotherapy and surgical procedures. An occupational therapist is a great help in improving the condition because he makes an objective measure of the patient's daily activities and will assess his lifestyle.

Nineteen paraplegic patients were entered into a trial to evaluate the use of functional electrical stimulation (FES) as a practical and reliable method of aiding standing. The clinical study used commercially available muscle stimulators, in contrast to the many previously reported case studies where prototype equipment has been used. This paper examines the effect of FES on muscle strength and spasticity in the paretic quadriceps muscle of paraplegic patients and demonstrates that only five of the subjects in the study exhibited an increase in muscle power of the stimulated quadriceps muscle, and that change in the level of spasticity, with varying patterns, occurred in all but two patients. [ABSTRACT FROM PUBLISHER]