224 research outputs found
Supernovae and Positron Annihilation
Radioactive nuclei, especially those created in SN explosion, have long been
suggested to be important contributors of galactic positrons. In this paper we
describe the findings of three independent OSSE/SMM/TGRS studies of positron
annihilation radiation, demonstrating that the three studies are largely in
agreement as to the distribution of galactic annihilation radiation. We then
assess the predicted yields and distributions of SN-synthesized radionuclei,
determining that they are marginally compatible with the findings of the
annihilation radiation studies.Comment: 7 pages, accepted for publication in New Astronomy Reviews (Astronomy
with Radioactivites III
Commitment and the Dynamics of Household Labor Supply
The extent to which individuals commit to their partner for life has important implications. This paper develops a lifecycle collective model of the household, through which it characterizes behavior in three prominent alternative types of commitment: full, limited, and no commitment. We propose a test that distinguishes between all three types based on how contemporaneous and historical news affect household behavior. Our test permits heterogeneity in the degree of commitment across households. Using recent data from the Panel Study of Income Dynamics, we reject full and no commitment, while we find strong evidence for limited commitment
The kidney failure risk equation predicts kidney failure: Validation in an Australian cohort
Aims: Predicting progression to kidney failure for patients with chronic kidney disease is essential for patient and clinicians' management decisions, patient prognosis, and service planning. The Tangri et al Kidney Failure Risk Equation (KFRE) was developed to predict the outcome of kidney failure. The KFRE has not been independently validated in an Australian Cohort. Methods: Using data linkage of the Tasmanian Chronic Kidney Disease study (CKD. TASlink) and the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA), we externally validated the KFRE. We validated the 4, 6, and 8-variable KFRE at both 2 and 5 years. We assessed model fit (goodness of fit), discrimination (Harell's C statistic), and calibration (observed vs predicted survival). Results: There were 18 170 in the cohort with 12 861 participants with 2 years and 8182 with 5 years outcomes. Of these 2607 people died and 285 progressed to kidney replacement therapy. The KFRE has excellent discrimination with C statistics of 0.96–0.98 at 2 years and 0.95–0.96 at 5 years. The calibration was adequate with well-performing Brier scores (0.004–0.01 at 2 years, 0.01–0.03 at 5 years) however the calibration curves, whilst adequate, indicate that predicted outcomes are systematically worse than observed. Conclusion: This external validation study demonstrates the KFRE performs well in an Australian population and can be used by clinicians and service planners for individualised risk prediction.Georgina L. Irish, Laura Cuthbertson, Alex Kitsos, Tim Saunder, Philip A. Clayton, Matthew D. Jos
Anti-allergic Activity of Stem Bark of Myrica esculenta Buch.-Ham. (Myricaceae)
Allergic diseases, such as allergic asthma, are hypersensitivity reactions initiated by immunological mechanisms. Myrica esculenta (M. esculenta) is known traditionally in Ayurveda to possess anti-asthmatic activity. The present investigation was undertaken to evaluate the effect of crude extract of stem bark of M. esculenta (Family Myricaceae, commonly known as Kaiphal) on experimental allergic reactions. Experimental models studied were allergic pleurisy and vascular permeability induced by acetic acid in mice. Pretreatment with M. esculenta (75 mg/kg and 150 mg/kg, p.o.) significantly inhibited the eosinophil accumulation (P < 0.01) respectively in the pleural cavity. M. esculenta (75 and 150 mg/kg, p.o.) significantly inhibited the rise in plasma exudation (57.12% and 59.77%, P < 0.01) induced by acetic acid in mice. These findings demonstrate that the crude extract from the stem bark of M. esculenta possesses antiallergic activity. This activity may be mediated by reducing the release of mediators such as histamine, inhibition of mast cell degranulation, and inhibition of eosinophil accumulation thereby preventing the release of cytokines and chemokines
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Geographic information retrieval in a mobile environment: evaluating the needs of mobile individuals
This paper describes research that aims to define the information needs of mobile individuals, to implement a mobile information system that can satisfy those needs, and finally to evaluate the performance of that system with end-users. First a review of the emerging discipline of geographic information retrieval (GIR) is presented as background to the more specific issue of mobile information retrieval. Following this, a user needs study is described evaluating the requirements of potential users of a mobile information system; the study finds that there is a strong geographic component to users' information needs. Next, four geographic post-query filters are described which attempt to represent the region of space associated with an individual's query made at some specific spatial location. These filters are spatial proximity (distance in space), temporal proximity (travel time), speed-heading prediction surfaces (likelihood of visiting locations) and visibility (locations that can be seen). Two of these filters — spatial proximity and speed-heading prediction surfaces — are implemented in a mobile information system and subsequently evaluated with users in an outdoor setting. The results of evaluation suggest that retrieved information to which post-query geographic filters have been applied is considered more relevant than unfiltered information, and that users find information sorted by spatial proximity to be more relevant than that sorted by a prediction surface of likely future locations. The paper closes with a discussion of the wider implications of these results for developers of mobile information systems and location-based services
Current state and future of pediatric allergology in Europe: A road map
The history of pediatric allergology (PA) in Europe is relatively youthful, dating back to 1984, when a small group of pediatricians founded the European Working Group on Pediatric Allergy and Immunology—later giving rise to ESPACI (European Society on Pediatric Allergology and Clinical Immunology). In 1990, the first dedicated journal, Pediatric Allergy and Immunology (PAI), was founded. There are striking differences across Europe, and even within European countries, in relation to the training pathways for doctors seeing children with allergic disease(s). In 2016, the EAACIClemens von Pirquet Foundation (CvP) organized and sponsored a workshop with the European Academy of Allergy and Clinical Immunology (EAACI) Pediatric Section. This collaboration focussed on the future of PA and specifically on education, research, and networking/ advocacy. The delegates representing many countries across Europe have endorsed the concept that optimal care of children with allergic diseases is delivered by pediatricians who have received dedicated training in allergy, or allergists who have received dedicated training in pediatrics. In order to meet the needs of children and families with allergic disease(s), the pediatric allergist is highly encouraged to develop several networks. Our challenge is to reinforce a clear strategic approach to scientific excellence to across our member base and to ensure and enhance the relevance of European pediatric research in allergy. With research opportunities in basic, translational, clinical, and epidemiologic trials, more trainees and trained specialists are needed and it is an exciting time to be a pediatric allergologist
Progress in Alternative Strategies to Combat Antimicrobial Resistance: Focus on Antibiotics
Antibiotic resistance, and, in a broader perspective, antimicrobial resistance (AMR), continues to evolve and spread beyond all boundaries. As a result, infectious diseases have become more challenging or even impossible to treat, leading to an increase in morbidity and mortality. Despite the failure of conventional, traditional antimicrobial therapy, in the past two decades, no novel class of antibiotics has been introduced. Consequently, several novel alternative strategies to combat these (multi-) drug-resistant infectious microorganisms have been identified. The purpose of this review is to gather and consider the strategies that are being applied or proposed as potential alternatives to traditional antibiotics. These strategies include combination therapy, techniques that target the enzymes or proteins responsible for antimicrobial resistance, resistant bacteria, drug delivery systems, physicochemical methods, and unconventional techniques, including the CRISPR-Cas system. These alternative strategies may have the potential to change the treatment of multi-drug-resistant pathogens in human clinical settings
Topical 1% Nalbuphine on corneal sensivity and epitheilization after experimental lamellar keratectomy in rabbits
The present study was aimed to evaluate the effects of topical 1% nalbuphine on corneal sensitivity and re-epithelialization, after lamellar keratectomy in rabbits. All protocols were approved by the Animal Care Comission of São Paulo State University (Protocol 028793-08) and were conducted in accordance with the Institutional Animal Committee and the Association for Research in Vision and Ophthalmology (ARVO) statement for the use of animals in research. Surgeries were performed on the left eye (Nalbuphine Group) and on the right eye (Control Group). Two groups were formed (n=10) and corneas received either 30µl of 1% nalbuphine (NG) or 30µl of 0,9% saline (CG). Treatments occurred at 7, 11, 15 and 19 hours. After the surgery, the corneas were stained with fluorescein and photographed daily; corneal touch threshold (CTT) was assessed with Cochet-Bonnet aesthesiometer, at 7 and 19 hours, 20 minutes after treatments. Data were statistically compared with repeated measures ANOVA and Bonferroni post-hoc test, and T test (P0.05); however, a higher area under the curve for both parameters was observed in the NG (2771), in comparison to CG (2164). Topical 1% nalbuphine did not change significantly corneal sensitivity and re-epithelialization, after experimental lamellar keratectomy in rabbits.Avaliaram-se os efeitos da nalbufina 1% sobre o limiar de sensibilidade corneal (LSC) e a epitelização corneal em coelhos submetidos à ceratectomia lamelar unilateral. Os procedimentos foram aprovados pela Comissão de Ética no Uso de Animais da Faculdade de Ciências Agrarias e Veterinárias da Universidade Estadual Paulista (Protocolo no 028793-08), de acordo com as normas do Institutional Animal Committee and the Association for Research in Vision and Ophthalmology (ARVO). Conceberam-se dois grupos (n=10) e os olhos foram tratados com 30µl de Nalbufina 1% (Olho esquerdo - GN) ou com 30µl de solução salina (Olho direito - GC), às 7, 11, 15 e 19 horas das ceratectomias unilaterais, até sua reepitelização. O limiar de sensibilidade corneal (LSC) foi avaliado 20 minutos após cada tratamento, 48 horas antes e depois da ceratectomia a intervalos regulares de 12 horas (7 e 19 horas) com estesiômetro de Cochet-Bonnet. Após a realização da cirurgia, diariamente, as córneas foram coradas com fluoresceína e registradas em fotos digitais para mensuração em software Image-J. A normalidade dos dados foi avaliada ao teste de Kolmogorov-Smirnov. O limiar de sensibilidade e a área ulcerada foram comparados ao teste de Bonferroni, após ANOVA de medias repetidas (P0,05), todavia, constatou-se maior área sob a curva, relativamente ao LSC, no GN (2771), comparativamente ao GC (2164). O tempo médio±DP de reepitelização no GN foi de 7,40±0,47 dias e de 8,90±0,31 dias no GC, não havendo diferença significativa entre os grupos (P=0,11). Como conclusão, tem-se que o uso tópico de nalbufina 1% não alterou significativamente o limiar de sensibilidade e a reepitelização corneais em coelhos submetidos a ceratectomia lamelar experimental
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