89 research outputs found
Advanced microfabrication technologies for microspacecraft
Advanced microfabrication technologies offer the prospect of reducing the weight and size of spacecraft through the use of lighter and stronger materials in conjunction with new mechanical/structural design concepts and design optimization methods. At the same time, electronic components have been scaled down while increasing functional utility. A two-fold benefit is derived for space applications through the use of less expensive components and the lower launch costs associated with lighter components. GE-CRD is actively pursuing research in these key technologies for a wide range of applications including satellites. These key technologies will be reviewed and an update on GE progress will be given. The need to reduce weight and lower cost, while maintaining product quality and reliability are primary drivers in the design of satellites, in general, and microsatellites in particular. For the structural subsystem, these requirements pose a complex design problem unless new mechanical design concepts and computer-aided design optimization methods are employed. Several new concepts, such as battery packs doubling as panel reinforcements and fuel tanks as integral structural members, need to utilized. In addition, new viscoelastic material damping concepts for spacecraft components provide for lighter weight/lower cost designs, while satisfying the structural dynamics requirements. High density interconnect (HDI) technology permits the use of bare IC's on a ceramic substrate with 90 percent active area utilization. A copper/polyimide multilayer structure is the backbone of the technology, which has demonstrated a size/weight reduction of greater than 10x compared to printed circuit board with performance up to the GHz level. HDI modules have exceptional mechanical robustness as evidenced by survival of 180 kg rapid acceleration tests. Microelectromechanical systems (MEMS) are redefining sensors and actuators by miniaturization through micromachining techniques. Sharing many fabrication steps with HDI, we have developed a new technique for surface micromachining of copper/polyimide structures using computer-aided laser patterning
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A thorough psychometric comparison between Athens Insomnia Scale and Insomnia Severity Index among patients with advanced cancer
For patients with cancer, sleep disturbance is commonplace. Using classical test theory and Rasch analyses, the present study compared two commonly used psychometric instruments for insomnia – Athens Insomnia Scale (AIS) and Insomnia Severity Index (ISI) – among patients with advanced cancer. Through convenience sampling, patients with cancer at stage III or IV (n=573; 326 males; mean age=61.3 years; SD=10.7) from eight oncology units of university hospitals in Iran participated in the study. All the participants completed the AIS, ISI, Edmonton Symptom Assessment Scale (ESAS), Hospital Anxiety and Depression Scale (HADS), General Health Questionnaire-12 (GHQ-12), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI). Additionally, 433 participants wore an Actigraph device for two continuous weekdays. Classical test theory and Rasch analysis both supported the construct validity for AIS (factor loadings from confirmatory factor analysis [CFA] = 0.61 to 0.87; test-retest reliability = 0.72 to 0.82; infit mean square [MnSq] = 0.81 to 1.17; outfit MnSq = 0.79 to 1.14) and for ISI (factor loadings from CFA = 0.61 to 0.81; test-retest reliability = 0.72 to 0.82; infit MnSq = 0.72 to 1.14; outfit MnSq = 0.76 to 1.11). Both AIS and ISI had significant associations with ESAS, HADS, GHQ-12, ESS, and PSQI, as well as having good sensitivity and specificity. Significant differences in the actigraphy measure were found between insomniacs and non-insomniacs based on AIS or ISI score. With promising results, healthcare providers can use either AIS or ISI to understand the insomnia of patients with advanced cancer
Use of complementary and alternative medicine in cancer patients: a European survey
Background: The aim of this study was to explore the use of complementary and alternative medicine (CAM) in cancer patients across a number of European countries. Methods: A descriptive survey design was developed. Fourteen countries participated in the study and data was collected through a descriptive questionnaire from 956 patients. Results: Data suggest that CAM is popular among cancer patients with 35.9% using some form of CAM (range among countries 14.8% to 73.1%). A heterogeneous group of 58 therapies were identified as being used. Herbal medicines and remedies were the most commonly used CAM therapies, together with homeopathy, vitamins/minerals, medicinal teas, spiritual therapies and relaxation techniques. Herbal medicine use tripled from use before diagnosis to use since diagnosis with cancer. Multivariate analysis suggested that the profile of the CAM user was that of younger people, female and with higher educational level. The source of information was mainly from friends/family and the media, while physicians and nurses played a small part in providing CAM-related information. The majority used CAM to increase the body's ability to fight cancer or improve physical and emotional well-being, and many seemed to have benefited from using CAM (even though the benefits were not necessarily related to the initial reason for using CAM). Some 4.4% of patients, however, reported side-effects, mostly transient. Conclusions: It is imperative that health professionals explore the use of CAM with their cancer patients, educate them about potentially beneficial therapies in light of the limited available evidence of effectiveness, and work towards an integrated model of health-care provisio
Trait anxiety predicts disease-specific health status in early-stage breast cancer patients
The objectives of this study were to examine the differences in health status (HS) of women with breast cancer (BC) at different moments in time, and between women scoring high and not high on trait anxiety, and to identify possible predictors of HS 6 and 12 months after surgery. Patients (N = 223) completed a trait anxiety questionnaire before diagnosis. Women who received a diagnosis of BC completed a BC-specific HS questionnaire 1, 3, 6 and 12 months after surgery. ANCOVA for repeated measures and multiple regression analysis were used in the analyses. Women scoring high on trait anxiety had significant (P < .005) lower Body image, worse Future perspective and Sexual functioning, and more Side-effects than women who did not score high on trait anxiety. At 6 and 12 months after surgery, the same aspects of HS were predicted by higher trait anxiety scores. Higher scores on trait anxiety resulted in worse scores on four HS domains, indicating that there should be more attention for this group of patients, even before treatment start
The post-vaccine microevolution of invasive Streptococcus pneumoniae
The 7-valent pneumococcal conjugated vaccine (PCV7) has affected the genetic population of Streptococcus pneumoniae in pediatric carriage. Little is known however about pneumococcal population genomics in adult invasive pneumococcal disease (IPD) under vaccine pressure. We sequenced and serotyped 349 strains of S. pneumoniae isolated from IPD patients in Nijmegen between 2001 and 2011. Introduction of PCV7 in the Dutch National Immunization Program in 2006 preluded substantial alterations in the IPD population structure caused by serotype replacement. No evidence could be found for vaccine induced capsular switches. We observed that after a temporary bottleneck in gene diversity after the introduction of PCV7, the accessory gene pool re-expanded mainly by genes already circulating pre-PCV7. In the post-vaccine genomic population a number of genes changed frequency, certain genes became overrepresented in vaccine serotypes, while others shifted towards non-vaccine serotypes. Whether these dynamics in the invasive pneumococcal population have truly contributed to invasiveness and manifestations of disease remains to be further elucidated. We suggest the use of whole genome sequencing for surveillance of pneumococcal population dynamics that could give a prospect on the course of disease, facilitating effective prevention and management of IPD
Adding high-intensity interval training to conventional training modalities: optimizing health-related outcomes during chemotherapy for breast cancer: the OptiTrain randomized controlled trial
Qualidade de vida de pacientes com câncer de mama em terapia adjuvante
O objetivo do estudo foi avaliar a Qualidade de Vida (QV), identificar os domínios afetados em pacientes comcâncer de mama em terapia adjuvante e correlacioná-los com características sócio-demográficas, clínicas e terapêuticas.Estudo transversal, realizado com 35 pacientes entre agosto de 2007 e dezembro de 2008. Utilizou-se oinstrumento Quality of Life Core-30-Questionnaire (QLQ-C30). A Qualidade de Vida geral foi considerada poucosatisfatória. Os domínios afetados foram: função emocional, insônia, dor e fadiga. Nas correlações, as pacientesacima de 60 anos apresentaram pior escore na função emocional, as submetidas à cirurgia referiram mais constipação,as que realizavam radioterapia obtiveram pior escore para QV geral e as que estavam em quimioterapia hámais de seis ciclos apresentaram a função emocional afetada e dispnéia. Concluiu-se que os tratamentos adjuvantesafetaram de algum modo as pacientes, causando déficit na função emocional e relataram mais sintomas, prejudicandoassim sua QV
Older women, breast cancer, and social support
One in ten women over the age of 65 will develop breast cancer. Despite this high incidence of breast cancer among older women, social support for them is often inadequate. This paper describes a qualitative study of the impact of a breast cancer diagnosis on older women from racially/ethnically diverse populations and their subsequent need for social support.
Forty-seven older African American, Asian American, Caucasian and Latina women between the ages of 65 to 83 participated in a larger study examining the impact of breast cancer on women from racially/ethnically diverse populations and the meaning and nature of social support. The women completed an in-depth qualitative interview on the psychosocial impact of breast cancer and the meaning and nature of social support.
The results indicate that there are variations in reactions to a breast cancer diagnosis among older women, and that these reactions impact their experiences with seeking social support at diagnosis and during treatment. Respondents were concerned about their aging bodies, potential dependency on others, and loss of autonomy. At the same time, the severity of cancer treatment and existing co-morbidities often meant they needed to learn to receive support, and to reach out if they had no support. The implications of these findings underscore the older cancer patient’s need to strengthen her supportive networks at the time of diagnosis, during treatment, and post-treatment
Meanings of existential uncertainty and certainty for people diagnosed with cancer and receiving palliative treatment: a life-world phenomenological study
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