Persistent luminescence mechanisms: human imagination at work

The present status and future progress of the mechanisms of persistent luminescence are critically treated with the present knowledge. The advantages to be achieved by a further need as well as the pitfalls of the excessive use of imagination are shown. As usual, in the beginning of the present era of persistent luminescence since the mid 1990s, the imagination played a more important role than the sparse solid experimental data and the chemical common sense and knowledge was largely ignored. Since some five years, the mechanistic studies seem to have reached the maturity and - perhaps deceivingly - it seems that there are only details to be solved. However, the development of red emitting nanocrystalline materials poses a challenge also to the more fundamental studies and interpretation. The questions still luring in the darkness include the problems how the increased surface area affects the defect structure and how the "persistent energy transfer" really works. There is still some light to be thrown onto these matters starting with agreeing on the terminology: the term phosphorescence should be abandoned altogether. The long lifetime of persistent luminescence is due to trapping of excitation energy, not to the forbidden nature of the luminescent transition. However, the technically well-suited term "afterglow" should be retained for harmful, short persistent luminescence. (C) 2012 Optical Society of America

Hurdles at work: perceptions of hospital food handlers

Abstract Background Food handlers have a very important role in preventing food contamination during its preparation and distribution. This responsibility is even greater in hospitals, since a large number of patients have low immunity and consequently food contamination by pathogenic bacteria could be particularly harmful. Therefore, a good working environment and periodic training should be provided to food handlers by upper management. Methods This study is qualitative research by means of focus group and thematic content analysis methodologies to examine, in detail, the statements by food handlers working in the milk and specific-diet kitchens in a hospital to understand the problems they face in the workplace. Results We found that food handlers are aware of the role they play in restoring patients' health; they consider it important to offer a good-quality diet. However, according to their perceptions, a number of difficulties prevent them from reaching this aim. These include: upper management not prioritizing human and material resources to the dietetic services when making resource allocation decisions; a perception that upper management considers their work to be of lesser importance; delayed overtime payments; lack of periodic training; managers lacking administrative skills; insufficient dietitian staff assistants, leading to overwork, at the same time as there is an excess of dietitians; unhealthy environmental working conditions – high temperature, high humidity, loud and constant noise level, poor ventilation; lack of food, and kitchen utensils and equipment; and relationship conflicts with chief dieticians and co-workers. Conclusion From these findings, improvement in staff motivation could be achieved by considering non-financial incentives, such as improvement in working conditions and showing appreciation and respect through supervision, training and performance appraisal. Management action, such as investments in intermediary management so that managers have the capacity to provide supportive supervision, as well as better use of performance appraisal and access to training, may help overcome the identified problems.

A light in the shadow: the use of Lucifer Yellow technique to demonstrate nectar reabsorption

Abstract Background Nectar reabsorption is a widely known phenomenon, related to the strategy of resource-recovery and also to maintain the nectar homeostasis at the nectary. The method currently performed to demonstrate nectar being reabsorbed involves the use of radioactive tracers applied to the nectary. Although this method works perfectly, it is complex and requires specific supplies and equipment. Therefore, here we propose an efficient method to obtain a visual demonstration of nectar reabsorption, adapting the use of Lucifer Yellow CH (LYCH), a fluorescent membrane-impermeable dye that can enter the vacuole by endocytosis. Results We applied a LYCH solution to the floral nectary (FN) of Cucurbita pepo L., which is a species known for its ability of nectar reabsorption, and to the extrafloral nectary (EFN) of Passiflora edulis Sims which does not reabsorb the secreted nectar. In all tests performed, we observed that LYCH stained the nectary tissues differentially according to the reabsorption ability of the nectary. The treated FN of C. pepo presented a concentrated fluorescence at the epidermis that decreased at the deeper nectary parenchyma, until reaching the vascular bundles, indicating nectar reabsorption in the flowers of the species. In contrast, treated EFN of P. edulis presented fluorescence only at the cuticle surface, indicating that nectar is not reabsorbed by that particular tissue. Conclusion LYCH is an efficient marker to demonstrate nectar reabsorption.

A rigorous approach to facilitate and guarantee the correctness of the genetic testing management in human genome information systems

Abstract Background Recent medical and biological technology advances have stimulated the development of new testing systems that have been providing huge, varied amounts of molecular and clinical data. Growing data volumes pose significant challenges for information processing systems in research centers. Additionally, the routines of genomics laboratory are typically characterized by high parallelism in testing and constant procedure changes. Results This paper describes a formal approach to address this challenge through the implementation of a genetic testing management system applied to human genome laboratory. We introduced the Human Genome Research Center Information System (CEGH) in Brazil, a system that is able to support constant changes in human genome testing and can provide patients updated results based on the most recent and validated genetic knowledge. Our approach uses a common repository for process planning to ensure reusability, specification, instantiation, monitoring, and execution of processes, which are defined using a relational database and rigorous control flow specifications based on process algebra (ACP). The main difference between our approach and related works is that we were able to join two important aspects: 1) process scalability achieved through relational database implementation, and 2) correctness of processes using process algebra. Furthermore, the software allows end users to define genetic testing without requiring any knowledge about business process notation or process algebra. Conclusions This paper presents the CEGH information system that is a Laboratory Information Management System (LIMS) based on a formal framework to support genetic testing management for Mendelian disorder studies. We have proved the feasibility and showed usability benefits of a rigorous approach that is able to specify, validate, and perform genetic testing using easy end user interfaces.

The double task of preventing malnutrition and overweight: a quasi-experimental community-based trial

Background: The Maternal-Child Pastoral is a volunteer-based community organization of the Dominican Republic that works with families to improve child survival and development. A program that promotes key practices of maternal and child care through meetings with pregnant women and home visits to promote child growth and development was designed and implemented. This study aims to evaluate the impact of the program on nutritional status indicators of children in the first two years of age. Methods: A quasi-experimental design was used, with groups paired according to a socioeconomic index, comparing eight geographical areas of intervention with eight control areas. The intervention was carried out by lay health volunteers. Mothers in the intervention areas received home visits each month and participated in a group activity held biweekly during pregnancy and monthly after birth. The primary outcomes were length and body mass index for age. Statistical analyses were based on linear and logistic regression models. Results: 196 children in the intervention group and 263 in the control group were evaluated. The intervention did not show statistically significant effects on length, but point estimates found were in the desired direction: mean difference 0.21 (95%CI −0.02; 0.44) for length-for-age Z-score and OR 0.50 (95%CI 0.22; 1.10) for stunting. Significant reductions of BMI-for-age Z-score (−0.31, 95%CI −0.49; -0.12) and of BMI-for-age > 85th percentile (0.43, 95%CI 0.23; 0.77) were observed. The intervention showed positive effects in some indicators of intermediary factors such as growth monitoring, health promotion activities, micronutrient supplementation, exclusive breastfeeding and complementary feeding. Conclusions: Despite finding effect measures pointing to effects in the desired direction related to malnutrition, we could only detect a reduction in the risk of overweight attributable to the intervention. The findings related to obesity prevention may be of interest in the context of the nutritional transition. Given the size of this study, the results are encouraging and we believe a larger study is warranted.

PReS-FINAL-2170: Work disability in adult patients with juvenile idiopathic arthritis (JIA)

Introduction Approximately 20% JIA patients enters adulthood with clinically active disease and disabled, therefore work condition may be affected. Objectives To assess the prevalence of work disability among adult patients with JIA regularly attending a tertiary heumatology center and to determine possible associated risk factors. Methods This was a cross-sectional study that enrolled 43 JIA patients according to 2004 revised ILAR criteria. A questionnaire was developed in order to evaluate working status and labor activity: occupation, current/previous work, employment status and withdrawal rate were actively searched. Demographic data, JIA characteristics, clinical activity (DAS28>2.6), therapeutic intervention, comorbidities, physical activity, sedentarism (WHO definitions), functional class (1991 ACR criteria), HAQ and SF-36 were recorded. The prevalence of work disability was calculated using 95% confidence interval, and compared to all parameters; qualitative variables were analyzed using tests of association (chi-square test) and quantitative variables by Mann-Whitney or student test. Results Patients' mean age was 29+7.4 yrs (range 19-41) with mean JIA duration = 17.2+12.3 yrs (range 3-33); 63% were males and 37% females. JIA subtypes were 64% polyarticular, 11% oligoarticular, 9% systemic, 9% ERA, 2% extended oligoarticular, 2% psoriatic arthritis; 7% had uveitis. Serum RF was positive in 21% and ANA in 21%. The majority (72%, n = 31) of JIA patients were employed, whereas 28% (n = 12) were currently not working. In the latter group, 83% (10/12) were retired due to JIA related disability. Further analysis comparing those currently working vs. Those not working revealed similar age (25,3 yrs vs.29,5 yrs, p = 0,09). Although not significantly, most patients currently working had Poly onset JIA (22 vs. 6 p = 0,37), higher frequencies of good education level >12 yrs of school (31 vs.9, p = 0,38), functional class I (p = 0,96), practiced regular physical activity (9 vs. 0, p = 0,89), were singles (26 vs. 8, p = 0,15). Both groups had comparable HAQ and DAS 28 scores (0,62 vs. 0.59, p = 0,47 and 2,51 vs.2,07, p = 0,64) and similar arthroplasty rate (8 vs. 4, p = 0,427). Frequencies of hypertension (3 vs.1, p = 0,999), dyslipidemia (1 vs. 1, p = 0,125), diabetes (1 vs. 0 p = 0,999), depression (1 vs. 0, p = 0,999) and smokers (3 vs. 1, p = 0,99) were alike in both groups. Remarkably, employed patients had higher SF 36 mental health component (84.0 vs. 70.42, P = 0.01). Conclusion High prevalence of almost 1/3 work disability and of retirement due to disease related incapacity remain major problems for adult JIA individuals. We also identified worse mental health in employed patients indicating that further research is needed, in addition to intense affirmative disability actions in order to remove possible disabling barriers and to adapt restrictive environments for these patients. Moreover, enhanced strategies and policy for inclusion of JIA patients in the job market is urged.