Downregulation of SPARC expression inhibits the invasion of human trophoblast cells in vitro.

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Yahong Jiang

Full Text Available Successful pregnancy depends on the precise regulation of extravilloustrophoblast (EVT invasion into the uterine decidua. SPARC (secreted protein acidic and rich in cysteine is a matricellular glycoprotein that plays critical roles in the pathologies associated with obesity and diabetes, as well as tumorigenesis. The objective of this study was to investigate the role of SPARC in the process of trophoblast invasion which shares many similarities with tumor cell invasion. By Western blot, higher expression of SPARC was observed in mouse brain, ovary and uterus compared to other mouse tissues. Immunohistochemistry analysis revealed a spatio-temporal expression of SPARC in mouse uterus in the periimplantation period. At the implantation site of d8 pregnancy, SPARC mainly accumulated in the secondary decidua zone (SDZ, trophoblast cells and blastocyst. The expression of SPARC was also detected in human placental villi and trophoblast cell lines. In a Matrigel invasion assay, we found SPARC-specific RNA interference significantly reduced the invasion of human extravilloustrophoblast HTR8/SVneo cells. Microarray analysis revealed that SPARC depletion upregulated the expression of interleukin 11 (IL11, KISS1, insulin-like growth factor binding protein 4 (IGFBP4, collagen type I alpha 1 (COLIA1, matrix metallopeptidase 9 (MMP9, and downregulated the expression of the alpha polypeptide of chorionic gonadotropin (CGA, MMP1, gap junction protein alpha 1 (GJA1, et al. The gene array result was further validated by qRT-PCR and Western blot. The present data indicate that SPARC may play an important role in the regulation of normal placentation by promoting the invasion of trophoblast cells into the uterine decidua.

SPARC expression in CML is associated to imatinib treatment and to inhibition of leukemia cell proliferation

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Giallongo Cesarina

2013-02-01

Full Text Available Abstract Background SPARC is a matricellular glycoprotein with growth-inhibitory and antiangiogenic activity in some cell types. The study of this protein in hematopoietic malignancies led to conflicting reports about its role as a tumor suppressor or promoter, depending on its different functions in the tumor microenvironment. In this study we investigated the variations in SPARC production by peripheral blood cells from chronic myeloid leukemia (CML patients at diagnosis and after treatment and we identified the subpopulation of cells that are the prevalent source of SPARC. Methods We evaluated SPARC expression using real-time PCR and western blotting. SPARC serum levels were detected by ELISA assay. Finally we analyzed the interaction between exogenous SPARC and imatinib (IM, in vitro, using ATP-lite and cell cycle analysis. Results Our study shows that the CML cells of patients at diagnosis have a low mRNA and protein expression of SPARC. Low serum levels of this protein are also recorded in CML patients at diagnosis. However, after IM treatment we observed an increase of SPARC mRNA, protein, and serum level in the peripheral blood of these patients that had already started at 3 months and was maintained for at least the 18 months of observation. This SPARC increase was predominantly due to monocyte production. In addition, exogenous SPARC protein reduced the growth of K562 cell line and synergized in vitro with IM by inhibiting cell cycle progression from G1 to S phase. Conclusion Our results suggest that low endogenous SPARC expression is a constant feature of BCR/ABL positive cells and that IM treatment induces SPARC overproduction by normal cells. This exogenous SPARC may inhibit CML cell proliferation and may synergize with IM activity against CML.

SPARC expression in CML is associated to imatinib treatment and to inhibition of leukemia cell proliferation

International Nuclear Information System (INIS)

Giallongo, Cesarina; Palumbo, Giuseppe A; Di Raimondo, Francesco; La Cava, Piera; Tibullo, Daniele; Barbagallo, Ignazio; Parrinello, Nunziatina; Cupri, Alessandra; Stagno, Fabio; Consoli, Carla; Chiarenza, Annalisa

2013-01-01

SPARC is a matricellular glycoprotein with growth-inhibitory and antiangiogenic activity in some cell types. The study of this protein in hematopoietic malignancies led to conflicting reports about its role as a tumor suppressor or promoter, depending on its different functions in the tumor microenvironment. In this study we investigated the variations in SPARC production by peripheral blood cells from chronic myeloid leukemia (CML) patients at diagnosis and after treatment and we identified the subpopulation of cells that are the prevalent source of SPARC. We evaluated SPARC expression using real-time PCR and western blotting. SPARC serum levels were detected by ELISA assay. Finally we analyzed the interaction between exogenous SPARC and imatinib (IM), in vitro, using ATP-lite and cell cycle analysis. Our study shows that the CML cells of patients at diagnosis have a low mRNA and protein expression of SPARC. Low serum levels of this protein are also recorded in CML patients at diagnosis. However, after IM treatment we observed an increase of SPARC mRNA, protein, and serum level in the peripheral blood of these patients that had already started at 3 months and was maintained for at least the 18 months of observation. This SPARC increase was predominantly due to monocyte production. In addition, exogenous SPARC protein reduced the growth of K562 cell line and synergized in vitro with IM by inhibiting cell cycle progression from G1 to S phase. Our results suggest that low endogenous SPARC expression is a constant feature of BCR/ABL positive cells and that IM treatment induces SPARC overproduction by normal cells. This exogenous SPARC may inhibit CML cell proliferation and may synergize with IM activity against CML

Evaluation of CFVS Performance with SPARC Model and Application

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Kim, Sung Il; Na, Young Su; Ha, Kwang Soon; Cho, Song Won [KAERI, Daejeon (Korea, Republic of)

2016-05-15

Containment Filtered Venting System (CFVS) is one of the important safety features to reduce the amount of released fission product into the environment by depressurizing the containment. KAERI has been conducted the integrated performance verification test of CFVS as a part of a Ministry of Trade, Industry and Energy (MOTIE) project. Generally, some codes are used in the case of wet type filter, such as SPARC, BUSCA, SUPRA, etc. Especially SPARC model is included in the MELCOR to calculate the fission product removal rate through the pool scrubbing. In this study, CFVS performance is evaluated using SPARC model in MELCOR according to the steam fraction in the containment. The calculation is mainly focused on the effect of steam fraction in the containment, and the calculation result is explained with the aerosol removal model in SPARC. Previous study on the OPR 1000 is applied to the result. There were two CFVS valve opening period and it is found that the CFVS performance is different in each case. The result of the study provides the fundamental data can be used to decide the CFVS operation time, however, more calculation data is necessary to generalize the result.

Λ CDM is Consistent with SPARC Radial Acceleration Relation

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Keller, B. W.; Wadsley, J. W., E-mail: kellerbw@mcmaster.ca [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)

2017-01-20

Recent analysis of the Spitzer Photometry and Accurate Rotation Curve (SPARC) galaxy sample found a surprisingly tight relation between the radial acceleration inferred from the rotation curves and the acceleration due to the baryonic components of the disk. It has been suggested that this relation may be evidence for new physics, beyond Λ CDM . In this Letter, we show that 32 galaxies from the MUGS2 match the SPARC acceleration relation. These cosmological simulations of star-forming, rotationally supported disks were simulated with a WMAP3 Λ CDM cosmology, and match the SPARC acceleration relation with less scatter than the observational data. These results show that this acceleration relation is a consequence of dissipative collapse of baryons, rather than being evidence for exotic dark-sector physics or new dynamical laws.

Elevated plasma SPARC levels are associated with insulin resistance, dyslipidemia, and inflammation in gestational diabetes mellitus.

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Lu Xu

Full Text Available OBJECTIVE: Recent studies suggested that secreted protein acidic and rich in cysteine (SPARC, a novel adipokine, is a key player in the pathology of obesity and type 2 diabetes. We aimed to determine whether concentrations of SPARC were altered in patients with gestational diabetes mellitus (GDM compared to normal glucose tolerance (NGT controls and to investigate the relationships between SPARC and metabolic parameters in pregnant women. DESIGN/METHODS: Cross-sectional study of 120 pregnant women with GDM and 60 controls with NGT, in a university hospital setting. Plasma levels of SPARC, adiponectin, fibroblast growth factor 21 (FGF21, insulin and proinsulin were determined by ELISA. RESULTS: GDM women had higher SPARC and lower adiponectin than NGT subjects; no difference was found in FGF21. SPARC levels were the lowest in subjects in the third tertile of insulin sensitivity index (ISIOGTT and correlated positively with pre-pregnant BMI, insulin and 3 h glucose during 100-g OGTT, HOMA-IR, fasting proinsulin, hsCRP and white blood cells count, and negatively with ISIOGTT, when adjusting for gestational age. Triglyceride (TG, Apolipoprotein A1, apolipoprotein B and lipoprotein (a correlated with SPARC in partial Pearson correlation. Correlations between SPARC with adiponectin, systolic blood pressure and TG were marginally significant in partial Spearman correlation analysis. In multivariate regression analysis, SPARC was an independent negative indicator of ISIOGTT. CONCLUSIONS: SPARC levels are correlated significantly with inflammation and may also be correlated with dyslipidemia and represent an independent determinant of insulin resistance in late pregnancy, indicating a potential role of SPARC in the pathophysiology of GDM.

Elevated plasma SPARC levels are associated with insulin resistance, dyslipidemia, and inflammation in gestational diabetes mellitus.

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Xu, Lu; Ping, Fan; Yin, Jinhua; Xiao, Xinhua; Xiang, Hongding; Ballantyne, Christie M; Wu, Huaizhu; Li, Ming

2013-01-01

Recent studies suggested that secreted protein acidic and rich in cysteine (SPARC), a novel adipokine, is a key player in the pathology of obesity and type 2 diabetes. We aimed to determine whether concentrations of SPARC were altered in patients with gestational diabetes mellitus (GDM) compared to normal glucose tolerance (NGT) controls and to investigate the relationships between SPARC and metabolic parameters in pregnant women. Cross-sectional study of 120 pregnant women with GDM and 60 controls with NGT, in a university hospital setting. Plasma levels of SPARC, adiponectin, fibroblast growth factor 21 (FGF21), insulin and proinsulin were determined by ELISA. GDM women had higher SPARC and lower adiponectin than NGT subjects; no difference was found in FGF21. SPARC levels were the lowest in subjects in the third tertile of insulin sensitivity index (ISIOGTT) and correlated positively with pre-pregnant BMI, insulin and 3 h glucose during 100-g OGTT, HOMA-IR, fasting proinsulin, hsCRP and white blood cells count, and negatively with ISIOGTT, when adjusting for gestational age. Triglyceride (TG), Apolipoprotein A1, apolipoprotein B and lipoprotein (a) correlated with SPARC in partial Pearson correlation. Correlations between SPARC with adiponectin, systolic blood pressure and TG were marginally significant in partial Spearman correlation analysis. In multivariate regression analysis, SPARC was an independent negative indicator of ISIOGTT. SPARC levels are correlated significantly with inflammation and may also be correlated with dyslipidemia and represent an independent determinant of insulin resistance in late pregnancy, indicating a potential role of SPARC in the pathophysiology of GDM.

SPARC Interacts with Actin in Skeletal Muscle in Vitro and in Vivo

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Jørgensen, Louise H; Jepsen, Pia Lørup; Boysen, Anders

2017-01-01

to actin. This interaction is present in regenerating myofibers of patients with Duchenne muscular dystrophy, polymyositis, and compartment syndrome. Analysis of the α-, β-, and γ-actin isoforms in SPARC knockout myoblasts reveals a changed expression pattern with dominance of γ-actin. In SPARC knockout......The cytoskeleton is an integral part of skeletal muscle structure, and reorganization of the cytoskeleton occurs during various modes of remodeling. We previously found that the extracellular matrix protein secreted protein acidic and rich in cysteine (SPARC) is up-regulated and expressed...... intracellularly in developing muscle, during regeneration and in myopathies, which together suggests that SPARC might serve a specific role within muscle cells. Using co-immunoprecipitation combined with mass spectrometry and verified by staining for direct protein-protein interaction, we find that SPARC binds...

Lack of the matricellular protein SPARC (secreted protein, acidic and rich in cysteine attenuates liver fibrogenesis in mice.

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Catalina Atorrasagasti

Full Text Available INTRODUCTION: Secreted Protein, Acidic and Rich in Cysteine (SPARC is a matricellular protein involved in many biological processes and found over-expressed in cirrhotic livers. By mean of a genetic approach we herein provide evidence from different in vivo liver disease models suggesting a profibrogenic role for SPARC. METHODS: Two in vivo models of liver fibrosis, based on TAA administration and bile duct ligation, were developed on SPARC wild-type (SPARC(+/+ and knock-out (SPARC(-/- mice. Hepatic SPARC expression was analyzed by qPCR. Fibrosis was assessed by Sirius Red staining, and the maturation state of collagen fibers was analyzed using polarized light. Necroinflammatory activity was evaluated by applying the Knodell score and liver inflammatory infiltration was characterized by immunohistochemistry. Hepatic stellate cell activation was assessed by α-SMA immunohistochemistry. In addition, pro-fibrogenic genes and inflammatory cytokines were measured by qPCR and/or ELISA. Liver gene expression profile was analyzed in SPARC(-/- and SPARC(+/+ mice using Affymetrix Mouse Gene ST 1.0 array. RESULTS: SPARC expression was found induced in fibrotic livers of mouse and human. SPARC(-/- mice showed a reduction in the degree of inflammation, mainly CD4+ cells, and fibrosis. Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/- mice when compared to SPARC(+/+ mice; in addition, MMP-2 expression was increased in SPARC(-/- mice. A reduction in the number of activated myofibroblasts was observed. Moreover, TGF-β1 expression levels were down-regulated in the liver as well as in the serum of TAA-treated knock-out animals. Ingenuity Pathway Analysis (IPA analysis suggested several gene networks which might involve protective mechanisms of SPARC deficiency against liver fibrogenesis and a better established machinery to repair DNA and detoxify from external chemical stimuli. CONCLUSIONS: Overall our data suggest that

Age and SPARC Change the Extracellular Matrix Composition of the Left Ventricle

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Lisandra E. de Castro Brás

2014-01-01

Full Text Available Secreted protein acidic and rich in cysteine (SPARC, a collagen-binding matricellular protein, has been implicated in procollagen processing and deposition. The aim of this study was to investigate age- and SPARC-dependent changes in protein composition of the cardiac extracellular matrix (ECM. We studied 6 groups of mice (n=4/group: young (4-5 months old, middle-aged (11-12 m.o., and old (18–29 m.o. C57BL/6J wild type (WT and SPARC null. The left ventricle (LV was decellularized to enrich for ECM proteins. Protein extracts were separated by SDS-PAGE, digested in-gel, and analyzed by HPLC-ESI-MS/MS. Relative quantification was performed by spectral counting, and changes in specific proteins were validated by immunoblotting. We identified 321 proteins, of which 44 proteins were extracellular proteins. Of these proteins, collagen III levels were lower in the old null mice compared to WT, suggestive of a role for SPARC in collagen deposition. Additionally, fibrillin showed a significant increase in the null middle-aged group, suggestive of increased microfibril deposition in the absence of SPARC. Collagen VI increased with age in both genotypes (>3-fold, while collagen IV showed increased age-associated levels only in the WT animals (4-fold, P<0.05. These changes may explain the previously reported age-associated increases in LV stiffness. In summary, our data suggest SPARC is a possible therapeutic target for aging induced LV dysfunction.

Secreted Protein Acidic and Rich in Cysteine (SPARC) in Human Skeletal Muscle

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Jørgensen, Louise H; Petersson, Stine J; Sellathurai, Jeeva

2009-01-01

indicated a function of SPARC in skeletal muscle. We therefore found it of interest to study SPARC expression in human skeletal muscle during development and in biopsies from Duchenne and Becker muscular dystrophy and congenital muscular dystrophy, congenital myopathy, inclusion body myositis...

SPARC is up-regulated during skeletal muscle regeneration and inhibits myoblast differentiation

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Petersson, Stine Juhl; Jørgensen, Louise Helskov; Andersen, Ditte C.

2013-01-01

Skeletal muscle repair is mediated primarily by the muscle stem cell, the satellite cell. Several factors, including extracellular matrix, are known to regulate satellite cell function and regeneration. One factor, the matricellular Secreted Protein Acidic and Rich in Cysteine (SPARC) is highly up......-regulated during skeletal muscle disease, but its function remains elusive. In the present study, we demonstrate a prominent yet transient increase in SPARC mRNA and protein content during skeletal muscle regeneration that correlates with the expression profile of specific muscle factors like MyoD, Myf5, Myf6......, Myogenin, NCAM, CD34, and M-Cadherin, all known to be implicated in satellite cell activation/proliferation following muscle damage. This up regulation was detected in more cell types. Ectopic expression of SPARC in the muscle progenitor cell line C2C12 was performed to mimic the high levels of SPARC seen...

Layer-by-layer nanoparticles as an efficient siRNA delivery vehicle for SPARC silencing.

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Tan, Yang Fei; Mundargi, Raghavendra C; Chen, Min Hui Averil; Lessig, Jacqueline; Neu, Björn; Venkatraman, Subbu S; Wong, Tina T

2014-05-14

Efficient and safe delivery systems for siRNA therapeutics remain a challenge. Elevated secreted protein, acidic, and rich in cysteine (SPARC) protein expression is associated with tissue scarring and fibrosis. Here we investigate the feasibility of encapsulating SPARC-siRNA in the bilayers of layer-by-layer (LbL) nanoparticles (NPs) with poly(L-arginine) (ARG) and dextran (DXS) as polyelectrolytes. Cellular binding and uptake of LbL NPs as well as siRNA delivery were studied in FibroGRO cells. siGLO-siRNA and SPARC-siRNA were efficiently coated onto hydroxyapatite nanoparticles. The multilayered NPs were characterized with regard to particle size, zeta potential and surface morphology using dynamic light scattering and transmission electron microscopy. The SPARC-gene silencing and mRNA levels were analyzed using ChemiDOC western blot technique and RT-PCR. The multilayer SPARC-siRNA incorporated nanoparticles are about 200 nm in diameter and are efficiently internalized into FibroGRO cells. Their intracellular fate was also followed by tagging with suitable reporter siRNA as well as with lysotracker dye; confocal microscopy clearly indicates endosomal escape of the particles. Significant (60%) SPARC-gene knock down was achieved by using 0.4 pmole siRNA/μg of LbL NPs in FibroGRO cells and the relative expression of SPARC mRNA reduced significantly (60%) against untreated cells. The cytotoxicity as evaluated by xCelligence real-time cell proliferation and MTT cell assay, indicated that the SPARC-siRNA-loaded LbL NPs are non-toxic. In conclusion, the LbL NP system described provides a promising, safe and efficient delivery platform as a non-viral vector for siRNA delivery that uses biopolymers to enhance the gene knock down efficiency for the development of siRNA therapeutics. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Association between SPARC mRNA expression, prognosis and response to neoadjuvant chemotherapy in early breast cancer: a pooled in-silico analysis.

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Hatem A Azim

Full Text Available INTRODUCTION: SPARC is an important regulator of the extracellular matrix and has been suggested to improve delivery of albumin-bound cytotoxics. However, little is known regarding its role in breast cancer (BC. METHODS: We conducted a pooled analysis of publically available datasets, in which BC patients who received no systemic therapy or received neoadjuvant chemotherapy were eligible. Patients were assigned to molecular subtypes using PAM-50. We computed a SPARC module (SPARC7, composed of genes with an absolute correlation with SPARC >0.7. In the systemically untreated cohort, we evaluated 1 expression of SPARC/SPARC7 according to breast cancer subtype, 2 association between SPARC/SPARC7 and biological processes related to proliferation, immune and stroma, and 3 association between SPARC/SPARC7 and relapse-free survival in a Cox model in all patients and in the different molecular subtypes adjusted for tumor size, nodal status, histological grade, and age. In the neoadjuvant cohort, we evaluated the association between SPARC and pCR in a logistic regression model, adjusted for the same clinicopathologic factors. RESULTS: 948 (10 datasets, and 791 (8 datasets patients were included in the systemically untreated and neoadjuvant cohorts, respectively. High SPARC expression was associated with small tumor size, low histological grade and luminal-A tumors (all p<0.0001. There was a positive correlation between SPARC and stroma-related modules but negative correlation with proliferation modules. High SPARC expression was associated with poor prognosis in patients with basal and HER2+ breast cancer even after adjusting for clinicopathologic parameters. In the neoadjuvant cohort, a subgroup analysis suggested that high SPARC is associated with low rates of pCR in the HER2 subtype. Same results were observed on replacing SPARC by SPARC7. CONCLUSION: This analysis suggests a potential role of SPARC in determining prognosis and response to primary

Impact of Secreted Protein Acidic and Rich in Cysteine (SPARC) Expression on Prognosis After Surgical Resection for Biliary Carcinoma.

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Toyota, Kazuhiro; Murakami, Yoshiaki; Kondo, Naru; Uemura, Kenichiro; Nakagawa, Naoya; Takahashi, Shinya; Sueda, Taijiro

2017-06-01

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that influences chemotherapy effectiveness and prognosis. The aim of this study was to investigate whether SPARC expression correlates with the postoperative survival of patients treated with surgical resection for biliary carcinoma. SPARC expression in resected biliary carcinoma specimens was investigated immunohistochemically in 175 patients. The relationship between SPARC expression and prognosis after surgery was evaluated using univariate and multivariate analyses. High SPARC expression in peritumoral stroma was found in 61 (35%) patients. In all patients, stromal SPARC expression was significantly associated with overall survival (OS) (P = 0.006). Multivariate analysis revealed that high stromal SPARC expression was an independent risk factor for poor OS (HR 1.81, P = 0.006). Moreover, high stromal SPARC expression was independently associated with poor prognosis in a subset of 118 patients treated with gemcitabine-based adjuvant chemotherapy (HR 2.04, P = 0.010) but not in the 57 patients who did not receive adjuvant chemotherapy (P = 0.21). Stromal SPARC expression correlated with the prognosis of patients with resectable biliary carcinoma, and its significance was enhanced in patients treated with adjuvant gemcitabine-based chemotherapy.

Association of serum sparc with insulin resistance in type-2 diabetes mellitus

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Nadeem, K.; Ahmed, U.; Arif, H.

2017-01-01

Objective: To determine the association of serum SPARC with insulin resistance in type-2 diabetes. Study Design: Descriptive study. Place and Duration of Study: Physiology department and CREAM lab, Army medical college, Rawalpindi, in collaboration with Military Hospital Rawalpindi, from Feb 2016 to Oct 2016. Material and Methods: Sixty individuals were recruited in this descriptive study. Thirty diagnosed cases of type- 2 DM were included, while thirty age and gender matched healthy individuals were included as controls through non-probability purposive sampling. Controls were labelled as group A, while cases were labelled as group B. Patients with type-1 DM, type-2 DM on insulin therapy, hyperglycemic states other than DM and inflammatory disorders were excluded from the study. Data were collected after informed and written consent. Blood samples were withdrawn under strict aseptic measures and serum was stored at -20 degree C. Serum insulin levels and serum SPARC levels were analyzed by enzyme linked immunosorbent assay (ELISA). Insulin resistance was determined using homeostasis model assessment of insulin resistance (HOMA-IR), and its value >1.5 was considered significant. Results: Fasting insulin levels were significantly higher in group B as compared with group A, supporting the diagnosis of type-2 DM. HOMA-IR values were greater than 1.5 in group B, thus establishing significant insulin resistance. Serum SPARC levels were significantly higher in group B than group A (17.7 ± 1.14 vs 8.7 ± 1.08 ng/ml) with p-value<0.001. Serum SPARC levels showed positive correlation with fasting insulin levels and HOMA-IR values. Conclusion: Our study showed a positive correlation between serum SPARC levels and insulin resistance, which indicates that SPARC plays an important role in the development of insulin resistance in type-2 diabetes mellitus. (author)

Study of Aerosols capture process in pool for injections Gaseous Jets at High Speeds: Enhancements SPARC90

International Nuclear Information System (INIS)

Berna, C.; Escriva, A.; Munoz-Cobo, J. L.; Herranz, L. E.

2012-01-01

Code The different expressions found in the literature have been analyzed in a modified version of the code SPARC90, those considered most appropriate. are compared in terms of decontamination factors, the results obtained using the original and modified (SPARC90-Jet) for SGTR accident conditions SPARC code.

[Effects of comprehensive therapy on serum SPARC levels in ankylosing spondylitis patients accompanied with osteoporosis].

Science.gov (United States)

Xu, Jing-ren; Lin, Yan; Zhang, Chun-Yan; Li, Wei-Min; Guo, Chen-Jun; Ye, Lei

2013-04-01

To observe the effects of comprehensive therapy on serum secreted protein acidic and rich in cysteine (SPARC) levels in ankylosing spondylitis (AS) patients accompanied with osteoporosis (OP), and to explore the possible mechanisms for SPARC in AS patients accompanied with osteoporosis. Totally 48 AS patients accompanied with OP (Group A) were treated with massage, intravenous infusion of Cervus and Cucumis Polypeptide Injection, and Bushen Quhan Zhiwang Decoction (BQZD) for 3 months. At the same time, 45 normal healthy subjects were recruited as the normal control group (Group B). Serum SPARC levels were measured by ELISA in Group A before and after comprehensive therapy and in those of Group B. The levels of bone mineral density of femoral neck (FN BMD), bone mineral density of 2 -4 lumbar spine (L2-4 BMD), bone specific alkaline phosphatase (BSAP), tumor necrosis factor alpha (TNF-alpha), and transforming growth factor beta-1 (TGF-beta1) were detected. Meanwhile, Bath AS disease activity index (BASDAI) and Bath AS functional index (BASFI) were detected in Group A before and after treatment. The correlations between the aforesaid indices and serum SPARC levels were analyzed. Serum SPARC levels were significantly lower in those of Group A than in those of Group B (175. 30 +/- 72.04 micro/L vs 190. 52 +/- 86. 13 microg/ L, P <0. 01). Serum SPARC levels in those of Group A were negatively correlated with TNF-alpha (r = -0.261, P <0.01), positively with L2-4 BMD, TGF-beta1, and BSAP (r =0.437,0.256, 0.385, P <0.05, P <0.01). L2-4BMD and BSAP were independently predictors of serum SPARC in patients of Group A. After comprehensive therapy, the levels of TNF-alpha, BASDAI, and BASFI obviously decreased, TGF-beta1, BSAP, L2-4 BMD, and FN BMD obviously increased (P <0. 05, P <0. 01). The serum SPARC levels also significantly increased (188.32 +/- 87.50 microg/L, P <0. 05). Comprehensive therapy could effectively improve the bone metabolism, clinical symptoms and the

Introduction to flow visualization system in SPARC test facility

International Nuclear Information System (INIS)

Lee, Wooyoung; Song, Simon; Na, Young Su; Hong, Seong Wan

2016-01-01

The released hydrogen can be accumulated and mixed by steam and air depending on containment conditions under severe accident, which generates flammable mixture. Hydrogen explosion induced by ignition source cause severe damage to a structure or facility. Hydrogen risk regarding mixing, distribution, and combustion has been identified by several expert groups and studied actively since TMI accident. A large-scale thermal-hydraulic experimental facility is required to simulate the complex severe accident phenomena in the containment building. We have prepared the test facility, called the SPARC (Spray, Aerosol, Recombiner, Combustion), to resolve the international open issues regarding hydrogen risk. Gas mixing and stratification test using helium instead of hydrogen and estimation of a stratification surface erosion of helium owing to the vertical jet flow will be performed in SPARC. The measurement system is need to observe the gas flow in the large scale test facility such as SPARC. The PIV (particle image velocimetry) system have been installed to visualize gas flow. We are preparing the test facility, called the SPARC, for estimation the thermal-hydraulic process of hydrogen in a closed containment building and the PIV system for quantitative assessment of gas flow. In particular, we will perform gas mixing and erosion of stratification surface test using helium which is the replacement of hydrogen. It will be evaluated by measuring 2D velocity field using the PIV system. The PIV system mainly consists of camera, laser and tracer particle. Expected maximum size of FOV is 750 x 750 mm 2 limited by focal length of lens and high power laser corresponding to 425mJ/pulse at 532 wavelength is required due to large FOV

Absence of SPARC results in increased cardiac rupture and dysfunction after acute myocardial infarction

NARCIS (Netherlands)

Schellings, Mark W. M.; Vanhoutte, Davy; Swinnen, Melissa; Cleutjens, Jack P.; Debets, Jacques; van Leeuwen, Rick E. W.; D'hooge, Jan; van de Werf, Frans; Carmeliet, Peter; Pinto, Yigal M.; Sage, E. Helene; Heymans, Stephane

2009-01-01

The matricellular protein SPARC (secreted protein, acidic and rich in cysteine, also known as osteonectin) mediates cell-matrix interactions during wound healing and regulates the production and/or assembly of the extracellular matrix (ECM). This study investigated whether SPARC functions in infarct

SPARC: Demonstrate burst-buffer-based checkpoint/restart on ATS-1.

Energy Technology Data Exchange (ETDEWEB)

Oldfield, Ron A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ulmer, Craig D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Widener, Patrick [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ward, H. Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2018-01-01

Recent high-performance computing (HPC) platforms such as the Trinity Advanced Technology System (ATS-1) feature burst buffer resources that can have a dramatic impact on an application’s I/O performance. While these non-volatile memory (NVM) resources provide a new tier in the storage hierarchy, developers must find the right way to incorporate the technology into their applications in order to reap the benefits. Similar to other laboratories, Sandia is actively investigating ways in which these resources can be incorporated into our existing libraries and workflows without burdening our application developers with excessive, platform-specific details. This FY18Q1 milestone summaries our progress in adapting the Sandia Parallel Aerodynamics and Reentry Code (SPARC) in Sandia’s ATDM program to leverage Trinity’s burst buffers for checkpoint/restart operations. We investigated four different approaches with varying tradeoffs in this work: (1) simply updating job script to use stage-in/stage out burst buffer directives, (2) modifying SPARC to use LANL’s hierarchical I/O (HIO) library to store/retrieve checkpoints, (3) updating Sandia’s IOSS library to incorporate the burst buffer in all meshing I/O operations, and (4) modifying SPARC to use our Kelpie distributed memory library to store/retrieve checkpoints. Team members were successful in generating initial implementation for all four approaches, but were unable to obtain performance numbers in time for this report (reasons: initial problem sizes were not large enough to stress I/O, and SPARC refactor will require changes to our code). When we presented our work to the SPARC team, they expressed the most interest in the second and third approaches. The HIO work was favored because it is lightweight, unobtrusive, and should be portable to ATS-2. The IOSS work is seen as a long-term solution, and is favored because all I/O work (including checkpoints) can be deferred to a single library.

Methylation of the SPARC gene promoter and its clinical implication in pancreatic cancer

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Lv Shunli

2010-03-01

Full Text Available Abstract Background The secreted protein acidic and rich in cysteine (SPARC plays a pivotal role in regulating cell-matrix interactions and tumor angiogenesis, proliferation, and migration. Detection of SPARC gene methylation may be useful as a tumorigenesis marker for early detection of pancreatic cancer. Methods Methylation of the SPARC gene transcriptional regulation region (TRR was detected using bisulfite-specific (BSP PCR-based sequencing analysis in 40 cases of pancreatic cancer and the adjacent normal tissues, 6 chronic pancreatitis tissues, and 6 normal pancreatic tissues. BSP cloning-based sequencing analysis was also performed in selected cases. Clinicopathological data from the cancer patients were collected and analyzed. Results Analysis of SPARC gene TRR methylation showed two hypermethylation wave peak regions: CpG Region 1 (CpG site 1-7 and CpG Region 2 (CpG site 8-12. Pancreatic tissues have shown methylation in both regions with gradual increases from normal, chronic pancreatitis, and adjacent normal tissues to cancerous tissues. However, Methylation of CpG Region 2 was more sensitive than CpG Region 1 in pancreatic tumorigenesis. Furthermore, the methylation level of CpG Region 2 was associated with increased tumor size and exposure to the risk factors (tobacco smoke and alcohol consumption for developing pancreatic cancer. Conclusion Methylation of the SPARC gene, specifically CpG Region 2, may be an early event during pancreatic tumorigenesis and should be further evaluated as a tumorigenesis marker for early detection of pancreatic cancer.

Opposite Expression of SPARC between the Liver and Pancreas in Streptozotocin-Induced Diabetic Rats.

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Kanikkai Raja Aseer

Full Text Available Secreted protein acidic and rich in cysteine (SPARC is a matricellular protein that regulates several cellular events, including inflammation and tissue remodelling. In this study, we investigated the tissue-specific expression of SPARC in streptozotocin (STZ-induced diabetes, and found that SPARC was significantly up-regulated in the liver while down-regulated in the pancreas of STZ-induced diabetic rats. Chronic inflammation occurred in the diabetic pancreas accompanied by up-regulation of CCAAT/enhancer-binding protein beta (C/EBPβ and its targets (TNFα, Il6, CRP, and Fn1 as well as myeloperoxidase (Mpo and C-X-C chemokine receptor type 2 (Cxcr2. Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis. PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver. On the contrary, CD95-dependent apoptosis was not observed in the diabetic pancreas due to up-regulation of PARP-1 and ATP depletion, resulting in necrosis. The cytoprotective machinery was damaged by pancreatic inflammation, whereas adequate antioxidant capacity indicates low oxidative stress in the diabetic liver. High and low cellular insulin content was found in the diabetic liver and pancreas, respectively. Furthermore, we identified six novel interacting partner proteins of SPARC by co-immunoprecipitation in the diabetic liver and pancreas, and their interactions with SPARC were predicted by bioinformatics tools. Taken together, opposite expression of SPARC in the diabetic liver and pancreas may be related to inflammation and immune cell infiltration, degrees of apoptosis and fibrosis, cytoprotective machinery, and cellular insulin levels.

Opposite Expression of SPARC between the Liver and Pancreas in Streptozotocin-Induced Diabetic Rats

Science.gov (United States)

Aseer, Kanikkai Raja; Kim, Sang Woo; Choi, Myung-Sook; Yun, Jong Won

2015-01-01

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that regulates several cellular events, including inflammation and tissue remodelling. In this study, we investigated the tissue-specific expression of SPARC in streptozotocin (STZ)-induced diabetes, and found that SPARC was significantly up-regulated in the liver while down-regulated in the pancreas of STZ-induced diabetic rats. Chronic inflammation occurred in the diabetic pancreas accompanied by up-regulation of CCAAT/enhancer-binding protein beta (C/EBPβ) and its targets (TNFα, Il6, CRP, and Fn1) as well as myeloperoxidase (Mpo) and C-X-C chemokine receptor type 2 (Cxcr2). Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis. PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver. On the contrary, CD95-dependent apoptosis was not observed in the diabetic pancreas due to up-regulation of PARP-1 and ATP depletion, resulting in necrosis. The cytoprotective machinery was damaged by pancreatic inflammation, whereas adequate antioxidant capacity indicates low oxidative stress in the diabetic liver. High and low cellular insulin content was found in the diabetic liver and pancreas, respectively. Furthermore, we identified six novel interacting partner proteins of SPARC by co-immunoprecipitation in the diabetic liver and pancreas, and their interactions with SPARC were predicted by bioinformatics tools. Taken together, opposite expression of SPARC in the diabetic liver and pancreas may be related to inflammation and immune cell infiltration, degrees of apoptosis and fibrosis, cytoprotective machinery, and cellular insulin levels. PMID:26110898

Estimating the melting point, entropy of fusion, and enthalpy of fusion of organic compounds via SPARC

Science.gov (United States)

The entropies of fusion, enthalies of fusion, and melting points of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modeled through a combination of interaction ...

Inhibition of HSP27 alone or in combination with pAKT inhibition as therapeutic approaches to target SPARC-induced glioma cell survival

Directory of Open Access Journals (Sweden)

Schultz Chad R

2012-04-01

Full Text Available Abstract Background The current treatment regimen for glioma patients is surgery, followed by radiation therapy plus temozolomide (TMZ, followed by 6 months of adjuvant TMZ. Despite this aggressive treatment regimen, the overall survival of all surgically treated GBM patients remains dismal, and additional or different therapies are required. Depending on the cancer type, SPARC has been proposed both as a therapeutic target and as a therapeutic agent. In glioma, SPARC promotes invasion via upregulation of the p38 MAPK/MAPKAPK2/HSP27 signaling pathway, and promotes tumor cell survival by upregulating pAKT. As HSP27 and AKT interact to regulate the activity of each other, we determined whether inhibition of HSP27 was better than targeting SPARC as a therapeutic approach to inhibit both SPARC-induced glioma cell invasion and survival. Results Our studies found the following. 1 SPARC increases the expression of tumor cell pro-survival and pro-death protein signaling in balance, and, as a net result, tumor cell survival remains unchanged. 2 Suppressing SPARC increases tumor cell survival, indicating it is not a good therapeutic target. 3 Suppressing HSP27 decreases tumor cell survival in all gliomas, but is more effective in SPARC-expressing tumor cells due to the removal of HSP27 inhibition of SPARC-induced pro-apoptotic signaling. 4 Suppressing total AKT1/2 paradoxically enhanced tumor cell survival, indicating that AKT1 or 2 are poor therapeutic targets. 5 However, inhibiting pAKT suppresses tumor cell survival. 6 Inhibiting both HSP27 and pAKT synergistically decreases tumor cell survival. 7 There appears to be a complex feedback system between SPARC, HSP27, and AKT. 8 This interaction is likely influenced by PTEN status. With respect to chemosensitization, we found the following. 1 SPARC enhances pro-apoptotic signaling in cells exposed to TMZ. 2 Despite this enhanced signaling, SPARC protects cells against TMZ. 3 This protection can be reduced

Current state of the construction of SPARC test facility for observing hydrogen′s behavior

Energy Technology Data Exchange (ETDEWEB)

Na, Young Su; Hong, Seong-Ho; Park, Ki Han; Hong, Seong-Wan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Hydrogen combustion can make a dynamic load, which can cause severe damage to a structure or facility. Many studies on hydrogen behavior, such as distribution, combustion and mitigation, have been conducted since the TMI accident, and they were recently summarized in. A large-scaled experimental facility is required for simulating the complex severe accident phenomena in a closed containment building. We are preparing the test facility, called the SPARC (Spray, Aerosol, Recombiner, Combustion), to resolve the international open issues regarding hydrogen risk as well as the validation of the Korean PAR (Passive Auto-catalytic Recombiner). This paper summarized the previous study submitted to the NUTHOS-11, which introduced the SPARC test facility. KAERI (Korea Atomic Energy Research Institute) is preparing a test facility, called the SPARC for an assessment of the containment integrity under a severe accident. In the SPARC test facility, the hydrogen behavior such as mixing with steam and air, distribution, and combustion will be observed under various thermal-hydraulic conditions. We will carry out the performance tests of the safety systems such as the spray, cooling fan, PAR, and igniter. The SPARC test facility consists of a pressure vessel with a 9.5 m height and 3.4 m diameter, and an operating system to control and measure the thermal hydraulic conditions. In a commissioning test, we verified the controllable thermal conditions. It took about 8,400 seconds to increase up to 5 bar. The increment rate of the atmosphere temperature is about 34° C/h from room temperature to 100° C.

Matricellular homologs in the foreign body response: hevin suppresses inflammation, but hevin and SPARC together diminish angiogenesis.

Science.gov (United States)

Barker, Thomas H; Framson, Paul; Puolakkainen, Pauli A; Reed, May; Funk, Sarah E; Sage, E Helene

2005-03-01

Implanted foreign materials, used to restore or assist tissue function, elicit an initial acute inflammatory response followed by chronic fibrosis that leads to the entrapment of the biomaterial in a thick, poorly vascularized collagenous capsule. Matricellular proteins, secreted macromolecules that interact with extracellular matrix proteins but do not in themselves serve structural roles, have been identified as important mediators of the foreign body response that includes inflammation, angiogenesis, and collagen synthesis and assembly. In this report we delineate functions of hevin and SPARC, two homologs of the SPARC family of matricellular proteins, in the foreign body response. Despite their sequence similarity, hevin and SPARC mediate different aspects of this fibrotic response. Using mice with targeted gene deletions, we show that hevin is central to the progression of biomaterial-induced inflammation whereas SPARC regulates the formation of the collagenous capsule. Although vascular density within the capsule is unaltered in the absence of either protein, SPARC-hevin double-null capsules show substantially increased numbers of vessels, indicating compensatory functions for these two proteins in the inhibition of angiogenesis. These results provide important information for further development of implant technology.

Commissioning of the SPARC Movable Emittance Meter and Its First Operation at PITZ

CERN Document Server

Catani, L; Cianchi, A

2005-01-01

For the SPARC Project a novel diagnostic device, called "Emittance-meter", has been conceived and constructed to perform a detailed study of the emittance compensation process in the SPARC photo-injector and to optimize the RF-gun and the accelerator working point. It consists of a movable emittance measurement system, based on the 1D pepper-pot method, installed between two long bellows with the possibility to scan a region 1.5 m long downstream the RF-gun. The construction of the device was completed in the first part of this year and a series of laboratory tests, to evaluate its performances, were carried out in Spring 2005. At the beginning of the summer the complete system was moved to DESY at Zeuthen to be installed on the Photo Injector Test Facility PITZ. After the commissioning it will used for measurements of the PITZ electron beam in the framework of a collaboration between the SPARC and PITZ Projects aiming on studies and operations with photo injectors.

Plasma density characterization at SPARC-LAB through Stark broadening of Hydrogen spectral lines

Energy Technology Data Exchange (ETDEWEB)

Filippi, F., E-mail: francesco.filippi@roma1.infn.it [Dipartimento di Scienze di Base e Applicate per l' Ingegneria (SBAI), ‘Sapienza’ Università di Roma, Via A. Scarpa 14-16, 00161 Roma (Italy); INFN-Roma1, Piazzale Aldo Moro, 2 00161 Roma (Italy); Anania, M.P.; Bellaveglia, M.; Biagioni, A.; Chiadroni, E. [Laboratori Nazionali di Frascati, INFN, Via E. Fermi, Frascati (Italy); Cianchi, A. [Dipartimento di Fisica, Universitá di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Roma (Italy); Di Giovenale, D.; Di Pirro, G.; Ferrario, M. [Laboratori Nazionali di Frascati, INFN, Via E. Fermi, Frascati (Italy); Mostacci, A.; Palumbo, L. [Dipartimento di Scienze di Base e Applicate per l' Ingegneria (SBAI), ‘Sapienza’ Università di Roma, Via A. Scarpa 14-16, 00161 Roma (Italy); INFN-Roma1, Piazzale Aldo Moro, 2 00161 Roma (Italy); Pompili, R.; Shpakov, V.; Vaccarezza, C.; Villa, F. [Laboratori Nazionali di Frascati, INFN, Via E. Fermi, Frascati (Italy); Zigler, A. [Hebrew University of Jerusalem, Jerusalem 91904 (Israel)

2016-09-01

Plasma-based acceleration techniques are of great interest for future, compact accelerators due to their high accelerating gradient. Both particle-driven and laser-driven Plasma Wakefield Acceleration experiments are foreseen at the SPARC-LAB Test Facility (INFN National Laboratories of Frascati, Italy), with the aim to accelerate high-brightness electron beams. In order to optimize the efficiency of the acceleration in the plasma and preserve the quality of the accelerated beam, the knowledge of the plasma electron density is mandatory. The Stark broadening of the Hydrogen spectral lines is one of the candidates used to characterize plasma density. The implementation of this diagnostic for plasma-based experiments at SPARC-LAB is presented. - Highlights: • Stark broadening of Hydrogen lines has been measured to determine plasma density. • Plasma density diagnostic tool for plasma-based experiments at SPARC-LAB is presented. • Plasma density in tapered laser triggered ablative capillary discharge was measured. • Results of plasma density measurements in ablative capillaries are shown.

Plasma density characterization at SPARC-LAB through Stark broadening of Hydrogen spectral lines

International Nuclear Information System (INIS)

Filippi, F.; Anania, M.P.; Bellaveglia, M.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Di Giovenale, D.; Di Pirro, G.; Ferrario, M.; Mostacci, A.; Palumbo, L.; Pompili, R.; Shpakov, V.; Vaccarezza, C.; Villa, F.; Zigler, A.

2016-01-01

Plasma-based acceleration techniques are of great interest for future, compact accelerators due to their high accelerating gradient. Both particle-driven and laser-driven Plasma Wakefield Acceleration experiments are foreseen at the SPARC-LAB Test Facility (INFN National Laboratories of Frascati, Italy), with the aim to accelerate high-brightness electron beams. In order to optimize the efficiency of the acceleration in the plasma and preserve the quality of the accelerated beam, the knowledge of the plasma electron density is mandatory. The Stark broadening of the Hydrogen spectral lines is one of the candidates used to characterize plasma density. The implementation of this diagnostic for plasma-based experiments at SPARC-LAB is presented. - Highlights: • Stark broadening of Hydrogen lines has been measured to determine plasma density. • Plasma density diagnostic tool for plasma-based experiments at SPARC-LAB is presented. • Plasma density in tapered laser triggered ablative capillary discharge was measured. • Results of plasma density measurements in ablative capillaries are shown.

Spot-Scanning Proton Arc (SPArc) Therapy: The First Robust and Delivery-Efficient Spot-Scanning Proton Arc Therapy

International Nuclear Information System (INIS)

Ding, Xuanfeng; Li, Xiaoqiang; Zhang, J. Michele; Kabolizadeh, Peyman; Stevens, Craig; Yan, Di

2016-01-01

Purpose: To present a novel robust and delivery-efficient spot-scanning proton arc (SPArc) therapy technique. Methods and Materials: A SPArc optimization algorithm was developed that integrates control point resampling, energy layer redistribution, energy layer filtration, and energy layer resampling. The feasibility of such a technique was evaluated using sample patients: 1 patient with locally advanced head and neck oropharyngeal cancer with bilateral lymph node coverage, and 1 with a nonmobile lung cancer. Plan quality, robustness, and total estimated delivery time were compared with the robust optimized multifield step-and-shoot arc plan without SPArc optimization (Arc_m_u_l_t_i_-_f_i_e_l_d) and the standard robust optimized intensity modulated proton therapy (IMPT) plan. Dose-volume histograms of target and organs at risk were analyzed, taking into account the setup and range uncertainties. Total delivery time was calculated on the basis of a 360° gantry room with 1 revolutions per minute gantry rotation speed, 2-millisecond spot switching time, 1-nA beam current, 0.01 minimum spot monitor unit, and energy layer switching time of 0.5 to 4 seconds. Results: The SPArc plan showed potential dosimetric advantages for both clinical sample cases. Compared with IMPT, SPArc delivered 8% and 14% less integral dose for oropharyngeal and lung cancer cases, respectively. Furthermore, evaluating the lung cancer plan compared with IMPT, it was evident that the maximum skin dose, the mean lung dose, and the maximum dose to ribs were reduced by 60%, 15%, and 35%, respectively, whereas the conformity index was improved from 7.6 (IMPT) to 4.0 (SPArc). The total treatment delivery time for lung and oropharyngeal cancer patients was reduced by 55% to 60% and 56% to 67%, respectively, when compared with Arc_m_u_l_t_i_-_f_i_e_l_d plans. Conclusion: The SPArc plan is the first robust and delivery-efficient proton spot-scanning arc therapy technique, which could potentially be

Spot-Scanning Proton Arc (SPArc) Therapy: The First Robust and Delivery-Efficient Spot-Scanning Proton Arc Therapy

Energy Technology Data Exchange (ETDEWEB)

Ding, Xuanfeng, E-mail: Xuanfeng.ding@beaumont.org; Li, Xiaoqiang; Zhang, J. Michele; Kabolizadeh, Peyman; Stevens, Craig; Yan, Di

2016-12-01

Purpose: To present a novel robust and delivery-efficient spot-scanning proton arc (SPArc) therapy technique. Methods and Materials: A SPArc optimization algorithm was developed that integrates control point resampling, energy layer redistribution, energy layer filtration, and energy layer resampling. The feasibility of such a technique was evaluated using sample patients: 1 patient with locally advanced head and neck oropharyngeal cancer with bilateral lymph node coverage, and 1 with a nonmobile lung cancer. Plan quality, robustness, and total estimated delivery time were compared with the robust optimized multifield step-and-shoot arc plan without SPArc optimization (Arc{sub multi-field}) and the standard robust optimized intensity modulated proton therapy (IMPT) plan. Dose-volume histograms of target and organs at risk were analyzed, taking into account the setup and range uncertainties. Total delivery time was calculated on the basis of a 360° gantry room with 1 revolutions per minute gantry rotation speed, 2-millisecond spot switching time, 1-nA beam current, 0.01 minimum spot monitor unit, and energy layer switching time of 0.5 to 4 seconds. Results: The SPArc plan showed potential dosimetric advantages for both clinical sample cases. Compared with IMPT, SPArc delivered 8% and 14% less integral dose for oropharyngeal and lung cancer cases, respectively. Furthermore, evaluating the lung cancer plan compared with IMPT, it was evident that the maximum skin dose, the mean lung dose, and the maximum dose to ribs were reduced by 60%, 15%, and 35%, respectively, whereas the conformity index was improved from 7.6 (IMPT) to 4.0 (SPArc). The total treatment delivery time for lung and oropharyngeal cancer patients was reduced by 55% to 60% and 56% to 67%, respectively, when compared with Arc{sub multi-field} plans. Conclusion: The SPArc plan is the first robust and delivery-efficient proton spot-scanning arc therapy technique, which could potentially be implemented

SPARC, FOXP3, CD8 and CD45 correlation with disease recurrence and long-term disease-free survival in colorectal cancer.

Directory of Open Access Journals (Sweden)

Angela Chew

Full Text Available BACKGROUND: SPARC is a matricellular protein involved in tissue remodelling, cell migration and angiogenesis, while forkhead box P3 (FOXP3 protein functions as a transcription factor involved in immune cell regulation. Both SPARC and FOXP3 can play an anti-tumorigenic role in cancer progression. The aim was to determine if SPARC, FOXP3, CD8 and CD45RO expression levels are associated with colorectal cancer (CRC stage, disease outcome and long-term cancer-specific survival (CSS in stage II and III CRC. METHODS AND FINDINGS: SPARC expression was initially assessed in 120 paired normal and stage I-IV CRCs. Subsequently, approximately 1000 paired patient samples of stage II or III CRCs in tissue microarrays were stained for SPARC, FOXP3, CD8 or CD45RO. Proportional hazards modelling assessed correlations between these markers and clinicopathological data, including disease outcome and cancer specific survival (CSS. Both SPARC and FOXP3 expression were significantly greater in CRC than normal colon (p<0.0001. High SPARC expression correlated with good disease outcome (≥60 mths without disease recurrence, p = 0.0039 and better long-term CSS in stage II CRC (<0.0001. In stage III CRC, high SPARC expression correlated with better long-term CSS (p<0.0001 and less adjuvant chemotherapy use (p = 0.01. High FOXP3 correlated with a good disease outcome, better long-term CSS and less adjuvant chemotherapy use in stage II (p<0.0037, <0.0001 and p = 0.04 respectively, but not in stage III CRC. High CD8 and CD45RO expression correlated with better disease outcome in stage II CRC, and better CSS, but the differences were not as marked as for SPARC and FOXP3. CONCLUSIONS: These data suggest that high SPARC and FOXP3 are associated with better disease outcome in stage II CRC and may be prognostic indicators of CSS. Further assessment of whether these markers predict patients at high risk of recurrence with stage II CRC and functional studies of these

Sun Tracker Operates a Year Between Calibrations

Science.gov (United States)

Berdahl, C. M.

1984-01-01

Low-cost modification of Sun tracker automatically compensates equation of time and seasonal variations in declination of Sun. Output of Scotch Yoke drive mechanism adjusted through proper sizing of crank, yoke and other components and through choice of gear ratios to approximate seasonal northand south motion of Sun. Used for industrial solar-energy monitoring and in remote meteorological stations.

Hybrid scheme of positron source at SPARC-LAB LNF facility

Energy Technology Data Exchange (ETDEWEB)

Abdrashitov, S.V., E-mail: abdsv@tpu.ru [National Research Tomsk Polytechnic University, Lenin Ave 30, 634050 Tomsk (Russian Federation); National Research Tomsk State University, Lenin Ave 36, 634050 Tomsk (Russian Federation); Bogdanov, O.V. [National Research Tomsk Polytechnic University, Lenin Ave 30, 634050 Tomsk (Russian Federation); Dabagov, S.B. [INFN Laboratori Nazionali di Frascati, Via E. Fermi 40, I-00044 Frascati, RM (Italy); RAS PN Lebedev Physical Institute, Leninskiy Prospekt 53, 119991 Moscow (Russian Federation); NRNU MEPhI, Kashirskoe Highway 31, 115409 Moscow (Russian Federation); Pivovarov, Yu.L.; Tukhfatullin, T.A. [National Research Tomsk Polytechnic University, Lenin Ave 30, 634050 Tomsk (Russian Federation)

2015-07-15

The hybrid scheme of the positron source for SPARC-LAB LNF facility (Frascati, Italy) is proposed. The comparison of the positron yield in a thin amorphous W converter of 0.1 mm thickness produced by bremsstrahlung, by axial 〈1 0 0〉 and planar (1 1 0) channeling radiations in a W crystal is performed for the positron energy range of 1 ÷ 3 MeV. It is shown that the radiation from 200 MeV electrons (parameters of SPARC-LAB LNF Frascati) in a 10 μm W crystal can produce positrons in the radiator of 0.1 mm thickness with the rate of 10–10{sup 2} s{sup −1} at planar channeling, of 10{sup 2}–10{sup 3} s{sup −1} at bremsstrahlung and of 10{sup 3}–10{sup 4} s{sup −1} at axial channeling.

Installation of Monte Carlo neutron and photon transport code system MCNP4

International Nuclear Information System (INIS)

Takano, Makoto; Sasaki, Mikio; Kaneko, Toshiyuki; Yamazaki, Takao.

1993-03-01

The continuous energy Monte Carlo code MCNP-4 including its graphic functions has been installed on the Sun-4 sparc-2 work station with minor corrections. In order to validate the installed MCNP-4 code, 25 sample problems have been executed on the work station and these results have been compared with the original ones. And, the most of the graphic functions have been demonstrated by using 3 sample problems. Further, additional 14 nuclides have been included to the continuous cross section library edited from JENDL-3. (author)

Advanced Technology and Mitigation (ATDM) SPARC Re-Entry Code Fiscal Year 2017 Progress and Accomplishments for ECP.

Energy Technology Data Exchange (ETDEWEB)

Crozier, Paul [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Howard, Micah [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rider, William J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Freno, Brian Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bova, Steven W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carnes, Brian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

The SPARC (Sandia Parallel Aerodynamics and Reentry Code) will provide nuclear weapon qualification evidence for the random vibration and thermal environments created by re-entry of a warhead into the earth’s atmosphere. SPARC incorporates the innovative approaches of ATDM projects on several fronts including: effective harnessing of heterogeneous compute nodes using Kokkos, exascale-ready parallel scalability through asynchronous multi-tasking, uncertainty quantification through Sacado integration, implementation of state-of-the-art reentry physics and multiscale models, use of advanced verification and validation methods, and enabling of improved workflows for users. SPARC is being developed primarily for the Department of Energy nuclear weapon program, with additional development and use of the code is being supported by the Department of Defense for conventional weapons programs.

The SPARC-LAB Thomson source

International Nuclear Information System (INIS)

Vaccarezza, C.; Alesini, D.; Anania, M.P.; Bacci, A.; Biagioni, A.; Bisesto, F.; Bellaveglia, M.; Cardarelli, P.; Cardelli, F.; Cianchi, A.; Chiadroni, E.; Croia, M.; Curcio, A.; Delogu, P.; Giovenale, D. Di; Domenico, G. Di; Pirro, G. Di; Drebot, I.; Ferrario, M.; Filippi, F.

2016-01-01

The SPARC-LAB Thomson source is a compact X-ray source based on the Thomson backscattering process presently under its second phase of commissioning at the LNF. The electron beam energy ranges between 30 and 150 MeV, the electrons collide head-on with the Ti:Sapphire FLAME laser pulse the energy of which ranges between 1 and 5 J with pulse lengths in the 25 fs–10 ps range, this provides an X-ray energy tunability in the range of 20–500 keV, with the further capability to generate strongly non-linear phenomena and to drive diffusion processes due to multiple and plural scattering effects. The experimental results of the obtained X-ray radiation are presented.

The SPARC-LAB Thomson source

Energy Technology Data Exchange (ETDEWEB)

Vaccarezza, C., E-mail: cristina.vaccarezza@lnf.infn.it [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Alesini, D.; Anania, M.P. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Bacci, A. [INFN-MI, Via Celoria 16, 20133 Milan (Italy); Biagioni, A.; Bisesto, F.; Bellaveglia, M. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Cardarelli, P. [University of Ferrara and INFN-FE, via Saragat 1, 44122 Ferrara (Italy); Cardelli, F. [University La Sapienza and INFN-Roma1, Piazzale Aldo Moro, 2 00161 Rome (Italy); Cianchi, A. [University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome (Italy); Chiadroni, E.; Croia, M.; Curcio, A. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Delogu, P. [University of Pisa and INFN-PI, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Giovenale, D. Di [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Domenico, G. Di [University of Ferrara and INFN-FE, via Saragat 1, 44122 Ferrara (Italy); Pirro, G. Di [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Drebot, I. [INFN-MI, Via Celoria 16, 20133 Milan (Italy); Ferrario, M. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Filippi, F. [University La Sapienza and INFN-Roma1, Piazzale Aldo Moro, 2 00161 Rome (Italy); and others

2016-09-01

The SPARC-LAB Thomson source is a compact X-ray source based on the Thomson backscattering process presently under its second phase of commissioning at the LNF. The electron beam energy ranges between 30 and 150 MeV, the electrons collide head-on with the Ti:Sapphire FLAME laser pulse the energy of which ranges between 1 and 5 J with pulse lengths in the 25 fs–10 ps range, this provides an X-ray energy tunability in the range of 20–500 keV, with the further capability to generate strongly non-linear phenomena and to drive diffusion processes due to multiple and plural scattering effects. The experimental results of the obtained X-ray radiation are presented.

TH-CD-209-10: Scanning Proton Arc Therapy (SPArc) - The First Robust and Delivery-Efficient Spot Scanning Proton Arc Therapy

International Nuclear Information System (INIS)

Ding, X; Li, X; Zhang, J; Kabolizadeh, P; Stevens, C; Yan, D

2016-01-01

Purpose: To develop a delivery-efficient proton spot-scanning arc therapy technique with robust plan quality. Methods: We developed a Scanning Proton Arc(SPArc) optimization algorithm integrated with (1)Control point re-sampling by splitting control point into adjacent sub-control points; (2)Energy layer re-distribution by assigning the original energy layers to the new sub-control points; (3)Energy layer filtration by deleting low MU weighting energy layers; (4)Energy layer re-sampling by sampling additional layers to ensure the optimal solution. A bilateral head and neck oropharynx case and a non-mobile lung target case were tested. Plan quality and total estimated delivery time were compared to original robust optimized multi-field step-and-shoot arc plan without SPArc optimization (Arcmulti-field) and standard robust optimized Intensity Modulated Proton Therapy(IMPT) plans. Dose-Volume-Histograms (DVH) of target and Organ-at-Risks (OARs) were analyzed along with all worst case scenarios. Total delivery time was calculated based on the assumption of a 360 degree gantry room with 1 RPM rotation speed, 2ms spot switching time, beam current 1nA, minimum spot weighting 0.01 MU, energy-layer-switching-time (ELST) from 0.5 to 4s. Results: Compared to IMPT, SPArc delivered less integral dose(−14% lung and −8% oropharynx). For lung case, SPArc reduced 60% of skin max dose, 35% of rib max dose and 15% of lung mean dose. Conformity Index is improved from 7.6(IMPT) to 4.0(SPArc). Compared to Arcmulti-field, SPArc reduced number of energy layers by 61%(276 layers in lung) and 80%(1008 layers in oropharynx) while kept the same robust plan quality. With ELST from 0.5s to 4s, it reduced 55%–60% of Arcmulti-field delivery time for the lung case and 56%–67% for the oropharynx case. Conclusion: SPArc is the first robust and delivery-efficient proton spot-scanning arc therapy technique which could be implemented in routine clinic. For modern proton machine with ELST close

Enhancement of the SPARC90 code to pool scrubbing events under jet injection regime

Energy Technology Data Exchange (ETDEWEB)

Berna, C., E-mail: ceberes@iie.upv.es [Instituto de Ingeniería Energética, Universitat Politècnica de València (UPV), Camino de Vera 14, 46022 Valencia (Spain); Escrivá, A.; Muñoz-Cobo, J.L. [Instituto de Ingeniería Energética, Universitat Politècnica de València (UPV), Camino de Vera 14, 46022 Valencia (Spain); Herranz, L.E., E-mail: luisen.herranz@ciemat.es [Unit of Nuclear Safety Research Division of Nuclear Fission, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain)

2016-04-15

Highlights: • Review of the most recent literature concerning submerged jets. • Emphasize all variables and processes occurring along the jet region. • Highlight the gaps of knowledge still existing related to submerged jets. • Enhancement of SPARC90-Jet to estimate aerosol removal under jet injection regime. • Validation of the SPARC90-Jet results against pool scrubbing experimental data. - Abstract: Submerged gaseous jets may have an outstanding relevance in many industrial processes and may be of particular significance in severe nuclear accident scenarios, like in the Fukushima accident. Even though pool scrubbing has been traditionally associated with low injection velocities, there are a number of potential scenarios in which fission product trapping in aqueous ponds might also occur under jet injection regime (like SGTR meltdown sequences in PWRs and SBO ones in BWRs). The SPARC90 code was developed to determine the fission product trapping in pools during severe accidents. The code assumes that carrier gas arrives at the water ponds at low or moderate velocities and it forms a big bubble that eventually detaches from the injection pipe. However, particle laden gases may enter the water at very high velocities resulting in a submerged gas jet instead. This work presents the fundamentals, major hypotheses and changes introduced into the code in order to estimate particle removal during gas injection in pools under the jet regime (SPARC90-Jet). A simplified and reliable approach to submerged jet hydrodynamics has been implemented on the basis of updated equations for jet hydrodynamics and aerosol removal, so that gas–liquid and droplet-particles interactions are described. The code modifications have been validated as far as possible. However, no suitable hydrodynamic tests have been found in the literature, so that an indirect validation has been conducted through comparisons against data from pool scrubbing experiments. Besides, this validation

Enhancement of the SPARC90 code to pool scrubbing events under jet injection regime

International Nuclear Information System (INIS)

Berna, C.; Escrivá, A.; Muñoz-Cobo, J.L.; Herranz, L.E.

2016-01-01

Highlights: • Review of the most recent literature concerning submerged jets. • Emphasize all variables and processes occurring along the jet region. • Highlight the gaps of knowledge still existing related to submerged jets. • Enhancement of SPARC90-Jet to estimate aerosol removal under jet injection regime. • Validation of the SPARC90-Jet results against pool scrubbing experimental data. - Abstract: Submerged gaseous jets may have an outstanding relevance in many industrial processes and may be of particular significance in severe nuclear accident scenarios, like in the Fukushima accident. Even though pool scrubbing has been traditionally associated with low injection velocities, there are a number of potential scenarios in which fission product trapping in aqueous ponds might also occur under jet injection regime (like SGTR meltdown sequences in PWRs and SBO ones in BWRs). The SPARC90 code was developed to determine the fission product trapping in pools during severe accidents. The code assumes that carrier gas arrives at the water ponds at low or moderate velocities and it forms a big bubble that eventually detaches from the injection pipe. However, particle laden gases may enter the water at very high velocities resulting in a submerged gas jet instead. This work presents the fundamentals, major hypotheses and changes introduced into the code in order to estimate particle removal during gas injection in pools under the jet regime (SPARC90-Jet). A simplified and reliable approach to submerged jet hydrodynamics has been implemented on the basis of updated equations for jet hydrodynamics and aerosol removal, so that gas–liquid and droplet-particles interactions are described. The code modifications have been validated as far as possible. However, no suitable hydrodynamic tests have been found in the literature, so that an indirect validation has been conducted through comparisons against data from pool scrubbing experiments. Besides, this validation

SATB1 regulates SPARC expression in K562 cell line through binding to a specific sequence in the third intron

International Nuclear Information System (INIS)

Li, K.; Cai, R.; Dai, B.B.; Zhang, X.Q.; Wang, H.J.; Ge, S.F.; Xu, W.R.; Lu, J.

2007-01-01

Special AT-rich binding protein 1 (SATB1), a cell type-specific nuclear matrix attachment region (MAR) DNA-binding protein, tethers to a specific DNA sequence and regulates gene expression through chromatin remodeling and HDAC (histone deacetylase complex) recruitment. In this study, a SATB1 eukaryotic expression plasmid was transfected into the human erythroleukemia K562 cell line and individual clones that stably over-expressed the SATB1 protein were isolated. Microarray analysis revealed that hundreds of genes were either up- or down-regulated in the SATB1 over-expressing K562 cell lines. One of these was the extra-cellular matrix glycoprotein, SPARC (human secreted protein acidic and rich in cysteine). siRNA knock-down of SATB1 also reduced SPARC expression, which was consistent with elevated SPARC levels in the SATB1 over-expressing cell line. Bioinformatics software Mat-inspector showed that a 17 bp DNA sequence in the third intron of SPARC possessed a high potential for SATB1 binding; a finding confirmed by Chromatin immunoprecipitation (ChIP) with anti-SATB1 antibody. Our results show for the first time that forced-expression of SATB1 in K562 cells triggers SPARC up-regulation by binding to a 17 bp DNA sequence in the third intron

A holistic approach to dissecting SPARC family protein complexity reveals FSTL-1 as an inhibitor of pancreatic cancer cell growth.

Science.gov (United States)

Viloria, Katrina; Munasinghe, Amanda; Asher, Sharan; Bogyere, Roberto; Jones, Lucy; Hill, Natasha J

2016-11-25

SPARC is a matricellular protein that is involved in both pancreatic cancer and diabetes. It belongs to a wider family of proteins that share structural and functional similarities. Relatively little is known about this extended family, but evidence of regulatory interactions suggests the importance of a holistic approach to their study. We show that Hevin, SPOCKs, and SMOCs are strongly expressed within islets, ducts, and blood vessels, suggesting important roles for these proteins in the normal pancreas, while FSTL-1 expression is localised to the stromal compartment reminiscent of SPARC. In direct contrast to SPARC, however, FSTL-1 expression is reduced in pancreatic cancer. Consistent with this, FSTL-1 inhibited pancreatic cancer cell proliferation. The complexity of SPARC family proteins is further revealed by the detection of multiple cell-type specific isoforms that arise due to a combination of post-translational modification and alternative splicing. Identification of splice variants lacking a signal peptide suggests the existence of novel intracellular isoforms. This study underlines the importance of addressing the complexity of the SPARC family and provides a new framework to explain their controversial and contradictory effects. We also demonstrate for the first time that FSTL-1 suppresses pancreatic cancer cell growth.

Monitoring the High-Energy Radiation Environment of Exoplanets Around Low-mass Stars with SPARCS (Star-Planet Activity Research CubeSat)

Science.gov (United States)

Shkolnik, Evgenya L.; Ardila, David; Barman, Travis; Beasley, Matthew; Bowman, Judd D.; Gorjian, Varoujan; Jacobs, Daniel; Jewell, April; Llama, Joe; Meadows, Victoria; Nikzad, Shouleh; Scowen, Paul; Swain, Mark; Zellem, Robert

2018-01-01

Roughly seventy-five billion M dwarfs in our galaxy host at least one small planet in the habitable zone (HZ). The stellar ultraviolet (UV) radiation from M dwarfs is strong and highly variable, and impacts planetary atmospheric loss, composition and habitability. These effects are amplified by the extreme proximity of their HZs (0.1–0.4 AU). Knowing the UV environments of M dwarf planets will be crucial to understanding their atmospheric composition and a key parameter in discriminating between biological and abiotic sources for observed biosignatures. The Star-Planet Activity Research CubeSat (SPARCS) will be a 6U CubeSat devoted to photometric monitoring of M stars in the far-UV and near-UV, measuring the time-dependent spectral slope, intensity and evolution of M dwarf stellar UV radiation. For each target, SPARCS will observe continuously over at least one complete stellar rotation (5 - 45 days). SPARCS will also advance UV detector technology by flying high quantum efficiency, UV-optimized detectors developed at JPL. These Delta-doped detectors have a long history of deployment demonstrating greater than five times the quantum efficiency of the detectors used by GALEX. SPARCS will pave the way for their application in missions like LUVOIR or HabEx, including interim UV-capable missions. SPARCS will also be capable of ‘target-of-opportunity’ UV observations for the rocky planets in M dwarf HZs soon to be discovered by NASA’s TESS mission, providing the needed UV context for the first habitable planets that JWST will characterize.Acknowledgements: Funding for SPARCS is provided by NASA’s Astrophysics Research and Analysis program, NNH16ZDA001N.

Monitoring the High-Energy Radiation Environment of Exoplanets around Lowmass Stars with SPARCS (Star-Planet Activity Research CubeSat)

Science.gov (United States)

Shkolnik, Evgenya

Seventy-five billion M dwarfs in our galaxy host at least one small planet in the habitable zone (HZ). The stellar ultraviolet (UV) radiation from M dwarfs is strong and highly variable, and impacts planetary atmospheric loss, composition and habitability. These effects are amplified by the extreme proximity of their HZs (0.1–0.4 AU). JWST will characterize HZ M dwarf planets and attempt the first spectroscopic search for life beyond the Solar System. Knowing the UV environments of M dwarf planets will be crucial to understanding their atmospheric composition and a key parameter in discriminating between biological and abiotic sources for observed biosignatures. The UV flux emitted during the super-luminous premain sequence phase of M stars drives water loss and photochemical O2 buildup for terrestrial planets within the HZ. This phase can persist for up to a billion years for the lowest mass M stars. Afterwards, UV-driven photochemistry during the main sequence phase strongly affects a planet’s atmosphere, could limit the planet’s potential for habitability, and may confuse studies of habitability by creating false chemical biosignatures. Our proposed CubeSat observatory will be the first mission to provide the time-dependent spectral slope, intensity and evolution of M dwarf stellar UV radiation. These measurements are crucial to interpreting observations of planetary atmospheres around low-mass stars. Mission: The Star-Planet Activity Research CubeSat (SPARCS) will be a 6U CubeSat devoted to monitoring 25 M stars in two UV bands: SPARCS far-UV (S- FUV: 153–171 nm) and SPARCS near-UV (S-NUV: 260– 300 nm). For each target, SPARCS will observe continuously between one and three complete stellar rotations (4–45 days) over a mission lifetime of 2 years. A UV characterization survey of M dwarfs, the most common of planet hosts, is a perfect experiment for a CubeSat: - UV astronomy cannot be done from the ground because of Earth’s atmospheric absorption

SPARC is up-regulated during skeletal muscle regeneration and inhibits myoblast differentiation

DEFF Research Database (Denmark)

Petersson, Stine Juhl; Jørgensen, Louise Helskov; Andersen, Ditte C

2013-01-01

in muscle disease. SPARC overexpression almost completely abolished myogenic differentiation in these cultures as determined by substantially reduced levels of myogenic factors (Pax7, Myf5, Myod, Mef2B, Myogenin, and Myostatin) and a lack of multinucleated myotubes. These results demonstrate...

Systems reliability analysis: applications of the SPARCS System-Reliability Assessment Computer Program

International Nuclear Information System (INIS)

Locks, M.O.

1978-01-01

SPARCS-2 (Simulation Program for Assessing the Reliabilities of Complex Systems, Version 2) is a PL/1 computer program for assessing (establishing interval estimates for) the reliability and the MTBF of a large and complex s-coherent system of any modular configuration. The system can consist of a complex logical assembly of independently failing attribute (binomial-Bernoulli) and time-to-failure (Poisson-exponential) components, without regard to their placement. Alternatively, it can be a configuration of independently failing modules, where each module has either or both attribute and time-to-failure components. SPARCS-2 also has an improved super modularity feature. Modules with minimal-cut unreliabiliy calculations can be mixed with those having minimal-path reliability calculations. All output has been standardized to system reliability or probability of success, regardless of the form in which the input data is presented, and whatever the configuration of modules or elements within modules

SPARC experiments at the high-energy storage ring

International Nuclear Information System (INIS)

Stöhlker, Thomas; Litvinov, Yuri A; Bagnoud, Vincent; Dimopoulou, Christina; Dolinskii, Alexei; Geppert, Christopher; Hagmann, Siegbert; Katayama, Takeshi; Kühl, Thomas; Nörtershäuser, Wilfried; Steck, Markus; Bechstedt, Ulf; Maier, Rudolf; Prasuhn, Dieter; Stockhorst, Hans; Schuch, Reinhold

2013-01-01

The physics program of the SPARC collaboration at the Facility for Antiproton and Ion Research (FAIR) focuses on the study of collision phenomena in strong and even extreme electromagnetic fields and on the fundamental interactions between electrons and heavy nuclei up to bare uranium. Here we give a short overview on the challenging physics opportunities of the high-energy storage ring at FAIR for future experiments with heavy-ion beams at relativistic energies with particular emphasis on the basic beam properties to be expected. (paper)

Research Library Issues: A Quarterly Report from ARL, CNI, and SPARC. RLI 277

Science.gov (United States)

Baughman, M. Sue, Ed.

2011-01-01

"Research Library Issues" ("RLI") is a quarterly report from ARL (Association of Research Libraries), CNI (Coalition of Networked Information), and SPARC (Scholarly Publishing and Academic Resources Coalition). This issue includes the following articles: (1) Rebalancing the Investment in Collections (H. Thomas Hickerson); (2)…

The SPARC_LAB femtosecond synchronization for electron and photon pulsed beams

Science.gov (United States)

Bellaveglia, M.; Gallo, A.; Piersanti, L.; Pompili, R.; Gatti, G.; Anania, M. P.; Petrarca, M.; Villa, F.; Chiadroni, E.; Biagioni, A.; Mostacci, A.

2015-05-01

The SPARC LAB complex hosts a 150 MeV electron photo-injector equipped with an undulator for FEL production (SPARC) together with a high power TW laser (FLAME). Recently the synchronization system reached the performance of < 100 fsRMS relative jitter between lasers, electron beam and RF accelerating fields. This matches the requirements for next future experiments: (i) the production of X-rays by means of Thomson scattering (first collisions achieved in 2014) and (ii) the particle driven PWFA experiment by means of multiple electron bunches. We report about the measurements taken during the machine operation using BAMs (Bunch Arrival Monitors) and EOS (Electro-Optical Sampling) system. A new R and D activity concerning the LWFA using the external injection of electron bunches in a plasma generated by the FLAME laser pulse is under design. The upgrade of the synchronization system is under way to guarantee the < 30 fs RMS jitter required specification. It foresees the transition from electrical to optical architecture that mainly affects the reference signal distribution and the time of arrival detection performances. The new system architecture is presented together with the related experimental data.

Research Library Issues: A Quarterly Report from ARL, CNI, and SPARC. RLI 279

Science.gov (United States)

Baughman, M. Sue, Ed.

2012-01-01

"Research Library Issues" ("RLI") is a quarterly report from ARL (Association of Research Libraries), CNI (Coalition of Networked Information), and SPARC (Scholarly Publishing and Academic Resources Coalition). This issue includes the following articles: (1) Digitization of Special Collections and Archives: Legal and Contractual Issues (Peter B.…

Research Library Issues: A Bimonthly Report from ARL, CNI, and SPARC. RLI 268

Science.gov (United States)

Barrett, G. Jaia, Ed.

2010-01-01

"Research Library Issues" ("RLI") is a bimonthly report from ARL (Association of Research Libraries), CNI (Coalition of Networked Information), and SPARC (Scholarly Publishing and Academic Resources Coalition). This special issue includes the following articles: (1) Themes within the ARL Strategic Plan 2010-2012 (Charles B. Lowry); (2) ARL…

ARM/GCSS/SPARC TWP-ICE CRM Intercomparison Study

Science.gov (United States)

Fridlind, Ann; Ackerman, Andrew; Petch, Jon; Field, Paul; Hill, Adrian; McFarquhar, Greg; Xie, Shaocheng; Zhang, Minghua

2010-01-01

Specifications are provided for running a cloud-resolving model (CRM) and submitting results in a standardized format for inclusion in a n intercomparison study and archiving for public access. The simulated case study is based on measurements obtained during the 2006 Tropical Warm Pool - International Cloud Experiment (TWP-ICE) led by the U. S. department of Energy Atmospheric Radiation Measurement (ARM) program. The modeling intercomparison study is based on objectives developed in concert with the Stratospheric Processes And their Role in Climate (SPARC) program and the GEWEX cloud system study (GCSS) program. The Global Energy and Water Cycle Experiment (GEWEX) is a core project of the World Climate Research PRogramme (WCRP).

Status of the SPARC Project

CERN Document Server

Serafini, Luca; Alessandria, Franco; Bacci, Alberto; Bellaveglia, Marco; Bertolucci, Sergio; Biagini, Maria; Boni, Roberto; Boscolo, Ilario; Boscolo, Manuela; Broggi, Francesco; Castellano, Michele; Catani, Luciano; Chiadroni, Enrica; Cialdi, Simone; Cianchi, Alessandro; Ciocci, Franco; Clozza, Alberto; Dattoli, Giuseppe; De Martinis, Carlo; Di Pirro, Giampiero; Dipace, Antonio; Doria, Andrea; Dowell, David; Drago, Alessandro; Emma, Paul; Esposito, Adolfo; Ferrario, Massimo; Ficcadenti, L; Filippetto, Daniele; Flora, F; Fusco, Valeria; Gabrielli, E; Gallerano, Gian P; Gallo, Alessandro; Gatti, Giancarlo; Ghigo, Andrea; Giannessi, Luca; Giove, Dario; Giovenale, Emilio; Guiducci, Susanna; Incurvati, Maurizio; Levi, Decio; Ligi, Carlo; Limborg-Deprey, Cecile; Marcellini, Fabio; Maroli, Cesare; Mattioli, Mario; Mauri, Marco; Medici, G; Messina, Giovanni; Migliorati, Mauro; Mostacci, Andrea; Musumeci, Pietro; Nisoli, Mauro; Ottaviani, P L; Pagnutti, Simonetta; Palumbo, Luigi; Parisi, Giovanni; Pellegrino, Luigi; Pelliccia, Daniele; Petrarca, Massimo; Petrillo, Vittoria; Picardi, Luigi; Preger, Miro; Quattromini, Marcello; Renieri, Alberto; Ricci, Ruggero; Rome, Massimiliano; Ronci, G; Ronsivalle, Concetta; Rosenzweig, James E; Rosetti, Maurizio; Sabia, Elio; Sanelli, Claudio; Sassi, Mauro; Serio, Mario; Sgamma, Francesco; Spataro, Bruno; Stagira, Salvatore; Stecchi, Alessandro; Stella, Angelo; Tazzari, Sergio; Tazzioli, Franco; Thomas Palmer, Dennis; Torre, A; Vaccarezza, Cristina; Vescovi, Mario; Vicario, Carlo; Zucchini, Alberto; de Silvestri, Sandro

2005-01-01

The SPARC project has entered its installation phase at INFN-LNF: its main goal is the promotion of an R&D activity oriented to the development of a high brightness photoinjector to drive SASE-FEL experiments. The design of the 150 MeV photoinjector has been completed and the construction of its main components is in progress, as well as the design of the 12 m undulator. In this paper we will report on the installation and test of some major components, like the Ti:Sa laser system to drive the photo-cathode, the RF gun, the RF power system, as well as some test results on the RF deflector and 4th harmonic X-band cavity prototypes. Advancements in the control and beam diagnostics systems will also be reported, in particular on the emittance-meter device for beam emittance measurements in the drift space downstream the RF gun. Recent results on laser pulse shaping, obtained with two alternative techniques (DAZZLER and Liquid Crystal Mask), show the feasibility of producing 10 ps flat-top laser pulses in the...

Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC-LAB test facility

Energy Technology Data Exchange (ETDEWEB)

Shpakov, V.; Anania, M.P.; Biagioni, A.; Chiadroni, E. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Cianchi, A. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); “Tor Vergata” University, via della Ricerca Scientifica 1, 00133 Rome (Italy); Curcio, A. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Dabagov, S. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); P.N. Lebedev Physical Institute RAS, Leninskiy Prospekt 53, 119991 Moscow (Russian Federation); NRNU “MEPhI”, Kashirskoe highway 31, 115409 Moscow (Russian Federation); Ferrario, M.; Filippi, F. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Marocchino, A. [Dipartimento SBAI Universitá di Roma ‘La Sapienza’, via Antonio Scarpa 14/16, 00161 Rome (Italy); Paroli, B. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Pompili, R. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Rossi, A.R. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Zigler, A. [Racah Institute of Physics Hebrew University of Jerusalem (Israel)

2016-09-01

Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC-LAB for such diagnostics tool, along with expected parameters of betatron radiation. - Highlights: • The betatron radiation parameters in SPARC-LAB wakefiled experiments were studied. • The differences with betatron radiation in other wake-field experiments were highlighted. • The solution for betatron radiation detection was investigated.

Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC-LAB test facility

International Nuclear Information System (INIS)

Shpakov, V.; Anania, M.P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Curcio, A.; Dabagov, S.; Ferrario, M.; Filippi, F.; Marocchino, A.; Paroli, B.; Pompili, R.; Rossi, A.R.; Zigler, A.

2016-01-01

Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC-LAB for such diagnostics tool, along with expected parameters of betatron radiation. - Highlights: • The betatron radiation parameters in SPARC-LAB wakefiled experiments were studied. • The differences with betatron radiation in other wake-field experiments were highlighted. • The solution for betatron radiation detection was investigated.

The SERTS-97 Rocket Experiment on Study Activity on the Sun: Flight 36.167-GS on 1997 November 18

Science.gov (United States)

Swartz, Marvin; Condor, Charles E.; Davila, Joseph M.; Haas, J. Patrick; Jordan, Stuart D.; Linard, David L.; Miko, Joseph J.; Nash, I. Carol; Novello, Joseph; Payne, Leslie J.;

A network biology approach evaluating the anticancer effects of bortezomib identifies SPARC as a therapeutic target in adult T-cell leukemia cells

Directory of Open Access Journals (Sweden)

Yu Zhang

2008-10-01

Full Text Available Junko H Ohyashiki1, Ryoko Hamamura2, Chiaki Kobayashi2, Yu Zhang2, Kazuma Ohyashiki21Intractable Immune System Disease Research Center, Tokyo Medical University, Tokyo, Japan; 2First Department of Internal Medicine, Tokyo Medical University, Tokyo, JapanAbstract: There is a need to identify the regulatory gene interaction of anticancer drugs on target cancer cells. Whole genome expression profiling offers promise in this regard, but can be complicated by the challenge of identifying the genes affected by hundreds to thousands of genes that induce changes in expression. A proteasome inhibitor, bortezomib, could be a potential therapeutic agent in treating adult T-cell leukemia (ATL patients, however, the underlying mechanism by which bortezomib induces cell death in ATL cells via gene regulatory network has not been fully elucidated. Here we show that a Bayesian statistical framework by VoyaGene® identified a secreted protein acidic and rich in cysteine (SPARC gene, a tumor-invasiveness related gene, as a possible modulator of bortezomib-induced cell death in ATL cells. Functional analysis using RNAi experiments revealed that inhibition of the expression SPARC by siRNA enhanced the apoptotic effect of bortezomib on ATL cells in accordance with an increase of cleaved caspase 3. Targeting SPARC may help to treat ATL patients in combination with bortezomib. This work shows that a network biology approach can be used advantageously to identify the genetic interaction related to anticancer effects.Keywords: network biology, adult T cell leukemia, bortezomib, SPARC

Consumer views on a new holistic screening tool for supportive and palliative-care needs: Sheffield Profile for Assessment and Referral for Care (SPARC): a survey of self-help support groups in health care.

Science.gov (United States)

Hughes, Philippa; Ahmed, Nisar; Winslow, Michelle; Walters, Stephen J; Collins, Karen; Noble, Bill

2015-08-01

Sheffield Profile for Assessment and Referral for Care (SPARC) was developed in response to concerns that palliative care may not be reaching all people who could benefit from it. Acceptability of the tool is an important step in developing its future use. To elicit the views of a wide variety of members of consumer and self-help support groups concerned with health care on the relevance, acceptability and the overall perception of using SPARC as an early holistic needs assessment tool in supportive and palliative care. This study was conducted in South Yorkshire and North Derbyshire (UK). Ninety-nine consumer and self-help groups were identified from information in the public domain. Thirty-eight groups participated. Packs containing study information and self-complete postal questionnaires were distributed to groups, and they were asked to circulate these to their members. Completed questionnaires were returned in pre-paid envelopes to the research team. 135 questionnaires and feedback forms were returned. The majority of respondents found SPARC easy to understand (93% (120/129; 95% Confidence Interval 87% to 96%) and complete (94% (125/133; 95% CI: 88% to 97%). A minority, 12.2% (16/131), of respondents found questions on SPARC 'too sensitive'. Overall, respondents considered SPARC an acceptable and relevant tool for clinical assessment of supportive and palliative-care needs. Whilst a small minority of people found SPARC difficult to understand (i.e. patients with cognitive impairments), most categories of service user found it relevant. Clinical studies are necessary to establish the clinical utility of SPARC. © 2013 John Wiley & Sons Ltd.

Topology Optimization of Large Scale Stokes Flow Problems

DEFF Research Database (Denmark)

Aage, Niels; Poulsen, Thomas Harpsøe; Gersborg-Hansen, Allan

2008-01-01

This note considers topology optimization of large scale 2D and 3D Stokes flow problems using parallel computations. We solve problems with up to 1.125.000 elements in 2D and 128.000 elements in 3D on a shared memory computer consisting of Sun UltraSparc IV CPUs.......This note considers topology optimization of large scale 2D and 3D Stokes flow problems using parallel computations. We solve problems with up to 1.125.000 elements in 2D and 128.000 elements in 3D on a shared memory computer consisting of Sun UltraSparc IV CPUs....

Laser-light sailing and non-stationary power stations applied to robotic star probes

International Nuclear Information System (INIS)

Matloff, Gregory L.

2000-01-01

The light sail has emerged as a leading contender to propel extrasolar expeditions. Because solar-sail performance is limited by the inverse-square law, one-way expeditions to other stars requiring voyage durations of a few centuries or less may be propelled by radiation pressure from a laser beam originating from a location closer to the Sun than the space probe. Maintaining a stationary laser power station in position between Sun and spacecraft for years or decades presents many technical challenges. This paper presents a variation on the laser power station that may be simpler to implement, in which the Sun-pumped laser power station follows the spacecraft on a parabolic or slightly hyperbolic trajectory

SPARC: MASS MODELS FOR 175 DISK GALAXIES WITH SPITZER PHOTOMETRY AND ACCURATE ROTATION CURVES

Energy Technology Data Exchange (ETDEWEB)

Lelli, Federico; McGaugh, Stacy S. [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Schombert, James M., E-mail: federico.lelli@case.edu [Department of Physics, University of Oregon, Eugene, OR 97403 (United States)

2016-12-01

We introduce SPARC ( Spitzer Photometry and Accurate Rotation Curves): a sample of 175 nearby galaxies with new surface photometry at 3.6  μ m and high-quality rotation curves from previous H i/H α studies. SPARC spans a broad range of morphologies (S0 to Irr), luminosities (∼5 dex), and surface brightnesses (∼4 dex). We derive [3.6] surface photometry and study structural relations of stellar and gas disks. We find that both the stellar mass–H i mass relation and the stellar radius–H i radius relation have significant intrinsic scatter, while the H i   mass–radius relation is extremely tight. We build detailed mass models and quantify the ratio of baryonic to observed velocity ( V {sub bar}/ V {sub obs}) for different characteristic radii and values of the stellar mass-to-light ratio (ϒ{sub ⋆}) at [3.6]. Assuming ϒ{sub ⋆} ≃ 0.5 M {sub ⊙}/ L {sub ⊙} (as suggested by stellar population models), we find that (i) the gas fraction linearly correlates with total luminosity; (ii) the transition from star-dominated to gas-dominated galaxies roughly corresponds to the transition from spiral galaxies to dwarf irregulars, in line with density wave theory; and (iii)  V {sub bar}/ V {sub obs} varies with luminosity and surface brightness: high-mass, high-surface-brightness galaxies are nearly maximal, while low-mass, low-surface-brightness galaxies are submaximal. These basic properties are lost for low values of ϒ{sub ⋆} ≃ 0.2 M {sub ⊙}/ L {sub ⊙} as suggested by the DiskMass survey. The mean maximum-disk limit in bright galaxies is ϒ{sub ⋆} ≃ 0.7 M {sub ⊙}/ L {sub ⊙} at [3.6]. The SPARC data are publicly available and represent an ideal test bed for models of galaxy formation.

ARL: A Bimonthly Report on Research Library Issues and Actions from ARL, CNI, and SPARC. Number 259

Science.gov (United States)

Barrett, G. Jaia, Ed.

2008-01-01

"ARL" is the bimonthly report on research library issues and actions from ARL (Association of Research Libraries), CNI (Coalition of Networked Information), and SPARC (Scholarly Publishing and Academic Resources Coalition). "ARL" reports on current issues of interest to academic and research library administrators, staff, and users; higher…

Sun Radio Interferometer Space Experiment (SunRISE)

Science.gov (United States)

Kasper, Justin C.; SunRISE Team

2018-06-01

The Sun Radio Interferometer Space Experiment (SunRISE) is a NASA Heliophysics Explorer Mission of Opportunity currently in Phase A. SunRISE is a constellation of spacecraft flying in a 10-km diameter formation and operating as the first imaging radio interferometer in space. The purpose of SunRISE is to reveal critical aspects of solar energetic particle (SEP) acceleration at coronal mass ejections (CMEs) and transport into space by making the first spatially resolved observations of coherent Type II and III radio bursts produced by electrons accelerated at CMEs or released from flares. SunRISE will focus on solar Decametric-Hectometric (DH, 0.1 space before major SEP events, but cannot be seen on Earth due to ionospheric absorption. This talk will describe SunRISE objectives and implementation. Presented on behalf of the entire SunRISE team.

Communicating safe sun practices to farm youth: a model and field test of a proposed curriculum

International Nuclear Information System (INIS)

Turk, D.R.; Parrott, R.; Martin, M.; Steiner, C.; Lewis, D.

1997-01-01

This project was designed to identify the barriers and motivators to farm youths' performance of skin cancer prevention and detection behavior in order to design curricula which could directly address both. The curriculum as developed was pilot tested in 1994 at the Georgia Healthy Farmers ''Farm Kids'' Safety Camp. The 82 participants, aged 8 to 15 years, were children of Georgia farmers. Eight Sun Safety classes were held over the course of two days. Participants were seated in a large conference room and were given a research questionnaire packet consisting of a skin cancer prevention/detection knowledge measure, three skin cancer related fact sheets, and a workbook to be used to rate various skin cancer prevention/detection materials and behaviors staged at centers around the room. A brief presentation about the dangers of sun exposure and skin cancer prevention behaviors was given after which subjects participated in three activities: a sun protection hat station, a sun block station, and skin self exam station. Student t- tests were conducted comparing the outcome expectancy scores for individuals who reported that they would wear the particular hat or sunscreen with the outcome expectancy scores for individuals who reported that they would not wear the particular hat or sunscreen. Participants who reported that they would wear the hat had significantly higher positive outcome expectancy scores than those who said that they would not wear those hats. For four out of five sun blocks, participants who reported that they would wear these blocks had significantly higher positive outcome expectancies than those reporting that they would not wear them. The authors conclude that health education curricula to promote sun safety to youth must focus on building positive outcome expectancies in relation to the most efficacious practices, and in drawing clear distinctions for youth among their options, so that they are able to make decisions for themselves. (author)

Design and Measurements of an X-Band Accelerating Cavity for SPARC

CERN Document Server

Alesini, David; Falone, Antonio; Ferrario, Massimo; Migliorati, Mauro; Mostacci, Andrea; Palpini, Federica; Palumbo, Luigi; Spataro, Bruno

2005-01-01

The paper presents the design of an X-band accelerating section for linearizing the longitudinal phase space in the Frascati Linac Coherent Light Source (SPARC). The structure, operating on the pi standing wave mode, is a 9 cells structure feeded by a central waveguide coupler and has been designed to obtain a 5 MV accelerating voltage. The 2D profile has been obtained using the e.m. codes SUPERFISH and OSCARD2D while the coupler has been designed using HFSS. Bead-pull measurement made on a copper prototype are illustrated and compared with the numerical results. Mechanical details of the realized prototype and RF properties of the structure as a function of the assembly characteristics are also discussed.

Space station operating system study

Science.gov (United States)

Horn, Albert E.; Harwell, Morris C.

1988-01-01

The current phase of the Space Station Operating System study is based on the analysis, evaluation, and comparison of the operating systems implemented on the computer systems and workstations in the software development laboratory. Primary emphasis has been placed on the DEC MicroVMS operating system as implemented on the MicroVax II computer, with comparative analysis of the SUN UNIX system on the SUN 3/260 workstation computer, and to a limited extent, the IBM PC/AT microcomputer running PC-DOS. Some benchmark development and testing was also done for the Motorola MC68010 (VM03 system) before the system was taken from the laboratory. These systems were studied with the objective of determining their capability to support Space Station software development requirements, specifically for multi-tasking and real-time applications. The methodology utilized consisted of development, execution, and analysis of benchmark programs and test software, and the experimentation and analysis of specific features of the system or compilers in the study.

The adaptation of the Sheffield Profile for Assessment and Referral for Care (SPARC) to the Polish clinical setting for needs assessment of advanced cancer patients.

Science.gov (United States)

Leppert, Wojciech; Majkowicz, Mikolaj; Ahmedzai, Sam H

2012-12-01

Assessment of the needs of advanced cancer patients is a very important issue in palliative care. The aim of the study was to adapt the Sheffield Profile for Assessment and Referral for Care (SPARC) to the Polish environment and evaluate its usefulness in needs assessment of patients with advanced cancer. A forward-back translation of the SPARC to Polish was done. The SPARC was used once in 58 consecutive patients with advanced cancer during follow-up. The patients were enrolled from a palliative care unit (25 patients), home care (18 patients), and a day care center (15 patients). The reliability was evaluated by establishing the internal consistency using Cronbach's alpha coefficients. Content validity was analyzed in accordance with the theories of needs by Murray and Maslow as a nonstatistical method of validity assessment. Factor analysis with principal components extraction and varimax rotation of raw data was used to reduce the set of data and assess the construct validity. There were differences regarding religious and spiritual issues and independence and activity between patients in the palliative care unit (worse results) and those at the day care center (better scores). Communication and need for more information items were associated with psychological, social, spiritual, and treatment issues. Cronbach's alpha coefficients and factor analysis demonstrated, respectively, satisfactory reliability and construct validity of the tool. The study demonstrated that the Polish version of the SPARC is a valid and reliable tool recommended for the needs assessment and symptom evaluation of patients with advanced cancer. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Lifestyle, sun worshipping and sun tanning - what about UV-A sun beds?

International Nuclear Information System (INIS)

Thune, P.

1991-01-01

This article considers the effects of ultraviolet (UV) light from the sun and UV-A sun beds on the skin. Sun worshipping and sun therapy has been en vogue for centuries, but in another way than used today. A changing lifestyle has led to an increase of various skin diseases, including skin cancer. Short wave UV-light (UV-B) in particular has been blamed for inducing not only erythema and pigmentation but also more chronic skin lesions. Long wave UV-light (UV-A) has been shown to be the cause of similar changes to the skin but the pigmentation is of another quality and affords less protection against the harmful effects of UV-B. A concept of sun reactive skin typing has been created. This is based on self-reported responses to an initial exposure to sun as regards tanning ability and erythema reaction. These two factors have certain practical consequences, not only for UV-phototherapy but also for a person's risk of developing skin cancer. Recently, several research groups and dermatologists have discouraged extensive use of UV-A sun beds because of side effects of varying degrees of seriousness. The possible implications of these side effects for the organism are not fully elucidated and may be more profound than known today. The British Photodermatology Group has issued more stringent rules for persons who, despite advice to the contrary, still wish to use UV-A sun beds. 14 refs., 1 tab

Sun Exposure, Sun-Related Symptoms, and Sun Protection Practices in an African Informal Traditional Medicines Market.

Science.gov (United States)

Wright, Caradee Y; Reddy, Tarylee; Mathee, Angela; Street, Renée A

2017-09-28

Informal workers in African market trade have little formal protection against sun exposure. We aimed to examine sun exposure, sun-related symptoms, and sun protection practices in an informal occupational setting. Trained fieldworkers asked 236 workers in the Warwick Junction market about their workplace, skin and eye sensitivity and skin colour, symptoms faced at work during the summer due to heat, and preventive measures. Data were analyzed using univariate logistic regression to assess the effect of gender and the risk of experiencing symptoms to sun exposure in relation to pre-existing diseases and perception of sun exposure as a hazard. Of the 236 participants, 234 were Black African and 141 (59.7%) were female. Portable shade was the most commonly used form of sun protection (69.9%). Glare from the sun (59.7%) and excessive sweating (57.6%) were commonly reported sun-related health symptoms. The use of protective clothing was more prevalent among those who perceived sun exposure as a hazard ( p = 0.003). In an informal occupational setting, sun exposure was high. Protective clothing and portable shade to eliminate heat and bright light were self-implemented. Action by local authorities to protect informal workers should consider sun exposure to support workers in their efforts to cope in hot weather.

Sun Exposure, Sun-Related Symptoms, and Sun Protection Practices in an African Informal Traditional Medicines Market

Directory of Open Access Journals (Sweden)

Caradee Y. Wright

2017-09-01

Full Text Available Informal workers in African market trade have little formal protection against sun exposure. We aimed to examine sun exposure, sun-related symptoms, and sun protection practices in an informal occupational setting. Trained fieldworkers asked 236 workers in the Warwick Junction market about their workplace, skin and eye sensitivity and skin colour, symptoms faced at work during the summer due to heat, and preventive measures. Data were analyzed using univariate logistic regression to assess the effect of gender and the risk of experiencing symptoms to sun exposure in relation to pre-existing diseases and perception of sun exposure as a hazard. Of the 236 participants, 234 were Black African and 141 (59.7% were female. Portable shade was the most commonly used form of sun protection (69.9%. Glare from the sun (59.7% and excessive sweating (57.6% were commonly reported sun-related health symptoms. The use of protective clothing was more prevalent among those who perceived sun exposure as a hazard (p = 0.003. In an informal occupational setting, sun exposure was high. Protective clothing and portable shade to eliminate heat and bright light were self-implemented. Action by local authorities to protect informal workers should consider sun exposure to support workers in their efforts to cope in hot weather.

Generation and characterization of ultra-short electron beams for single spike infrared FEL radiation at SPARC_LAB

Science.gov (United States)

Villa, F.; Anania, M. P.; Artioli, M.; Bacci, A.; Bellaveglia, M.; Bisesto, F. G.; Biagioni, A.; Carpanese, M.; Cardelli, F.; Castorina, G.; Chiadroni, E.; Cianchi, A.; Ciocci, F.; Croia, M.; Curcio, A.; Dattoli, G.; Gallo, A.; Di Giovenale, D.; Di Palma, E.; Di Pirro, G.; Ferrario, M.; Filippi, F.; Giannessi, L.; Giribono, A.; Marocchino, A.; Massimo, F.; Mostacci, A.; Petralia, A.; Petrarca, M.; Petrillo, V.; Piersanti, L.; Pioli, S.; Pompili, R.; Romeo, S.; Rossi, A. R.; Scifo, J.; Shpakov, V.; Vaccarezza, C.

2017-09-01

The technique for producing and measuring few tens of femtosecond electron beams, and the consequent generation of few tens femtoseconds single spike FEL radiation pulses at SPARC_LAB is presented. The undulator has been used in the double role of radiation source and diagnostic tool for the characterization of the electron beam. The connection between the electron bunch length and the radiation bandwidth is analyzed.

Sun and Sun Worship in Different Cultures

Science.gov (United States)

Farmanyan, S. V.; Mickaelian, A. M.

2014-10-01

The Sun symbol is found in many cultures throughout history, it has played an important role in shaping our life on Earth since the dawn of time. Since the beginning of human existence, civilisations have established religious beliefs that involved the Sun's significance to some extent. As new civilisations and religions developed, many spiritual beliefs were based on those from the past so that there has been an evolution of the Sun's significance throughout cultural development. For comparing and finding the origin of the Sun we made a table of 66 languages and compared the roots of the words. For finding out from where these roots came from, we also made a table of 21 Sun Gods and Goddesses and proved the direct crossing of language and mythology.

Skin Tone Dissatisfaction, Sun Exposure, and Sun Protection in Australian Adolescents.

Science.gov (United States)

Hutchinson, Amanda D; Prichard, Ivanka; Ettridge, Kerry; Wilson, Carlene

2015-08-01

This study aimed to assess the adoption of sun protection and sun exposure behaviors, the extent to which these behaviors group together, and the relationship between skin tone dissatisfaction and sun-related behaviors in South Australian adolescents (aged 12-17). A total of 2,875 secondary school students (1,461 male and 1,414 female) completed a questionnaire including questions about sun protection and sun exposure behaviors and skin tone dissatisfaction. Regular adoption of sun protection behaviors was low and ranged from 20% (wearing protective clothing) to 44% (sunscreen use). A principal components analysis identified four subgroups of sun-related behaviors: sun protection, appearance enhancement, sun avoidance, and sun exposure. Females had significantly higher skin tone dissatisfaction than males. Skin tone dissatisfaction was associated with decreased sun protection and avoidance and increased appearance enhancement and sun exposure in both males and females. Skin tone dissatisfaction plays an important role in Australian adolescents' sun-related behavior. Appearance-based interventions may be effective in reducing skin cancer risk through reduced sun exposure.

Atomic physics with highly-charged heavy ions at the GSI future facility: The scientific program of the SPARC collaboration

International Nuclear Information System (INIS)

Stoehlker, Th.; Beier, T.; Beyer, H.F.; Bosch, F.; Braeuning-Demian, A.; Gumberidze, A.; Hagmann, S.; Kozhuharov, C.; Kuehl, Th.; Liesen, D.; Mann, R.; Mokler, P.H.; Quint, W.; Schuch, R.; Warczak, A.

2005-01-01

In the current report a short overview about the envisioned program of the atomic physics research collaboration SPARC (Stored Particle Atomic Research Collaboration, at the new international accelerator Facility for Antiproton and Ion Research (FAIR) at GSI is given. In addition, a condensed description of the planned experimental areas devoted to atomic physics research at the new facility is presented

Sun Allergy

Science.gov (United States)

Sun allergy Overview Sun allergy is a term often used to describe a number of conditions in which an itchy red rash occurs on skin that has been exposed to sunlight. The most common form of sun allergy is ...

Software to model AXAF-I image quality

Science.gov (United States)

Ahmad, Anees; Feng, Chen

1995-01-01

A modular user-friendly computer program for the modeling of grazing-incidence type x-ray optical systems has been developed. This comprehensive computer software GRAZTRACE covers the manipulation of input data, ray tracing with reflectivity and surface deformation effects, convolution with x-ray source shape, and x-ray scattering. The program also includes the capabilities for image analysis, detector scan modeling, and graphical presentation of the results. A number of utilities have been developed to interface the predicted Advanced X-ray Astrophysics Facility-Imaging (AXAF-I) mirror structural and thermal distortions with the ray-trace. This software is written in FORTRAN 77 and runs on a SUN/SPARC station. An interactive command mode version and a batch mode version of the software have been developed.

Wireless Connectivity to ATM Communication Grid

National Research Council Canada - National Science Library

Rajaravivarma, Veeramuthu

1998-01-01

The AFOSR funds were used to purchase a 12 port Fore ATM switch, ATM network interface cards, a SUN UltraSPARC workstation, Lucent WavePoint wireless bridge, and Lucent WaveLAN wireless network interface cards...

Sun protection

Science.gov (United States)

... sun exposure. The start of summer is when UV rays can cause the most skin damage. Use sun protection, even on cloudy days. Clouds and haze don't protect you from the sun. Avoid surfaces that reflect light, such as water, sand, concrete, snow, and areas ...

Longitudinal social networks impacts on weight and weight-related behaviors assessed using mobile-based ecological momentary assessments: Study Protocols for the SPARC study

Directory of Open Access Journals (Sweden)

Meg Bruening

2016-08-01

Full Text Available Abstract Background The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing risk of overweight/obesity. Currently, little is understood about how changing friendship networks shape weight gain behaviors. This paper describes the recruitment, data collection, and data analytic protocols for the SPARC (Social impact of Physical Activity and nutRition in College study, a longitudinal examination of the mechanisms by which friends and friendship networks influence nutrition and physical activity behaviors and weight gain in the transition to college life. Methods The SPARC study aims to follow 1450 university freshmen from a large university over an academic year, collecting data on multiple aspects of friends and friendship networks. Integrating multiple types of data related to student lives, ecological momentary assessments (EMAs are administered via a cell phone application, devilSPARC. EMAs collected in four 1-week periods (a total of 4 EMA waves are integrated with linked data from web-based surveys and anthropometric measurements conducted at four times points (for a total of eight data collection periods including EMAs, separated by ~1 month. University databases will provide student card data, allowing integration of both time-dated data on food purchasing, use of physical activity venues, and geographical information system (GIS locations of these activities relative to other students in their social networks. Discussion Findings are intended to guide the development of more effective interventions to enhance behaviors among college students that protect against weight gain during college.

Longitudinal social networks impacts on weight and weight-related behaviors assessed using mobile-based ecological momentary assessments: Study Protocols for the SPARC study.

Science.gov (United States)

Bruening, Meg; Ohri-Vachaspati, Punam; Brewis, Alexandra; Laska, Melissa; Todd, Michael; Hruschka, Daniel; Schaefer, David R; Whisner, Corrie M; Dunton, Genevieve

2016-08-30

The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing risk of overweight/obesity. Currently, little is understood about how changing friendship networks shape weight gain behaviors. This paper describes the recruitment, data collection, and data analytic protocols for the SPARC (Social impact of Physical Activity and nutRition in College) study, a longitudinal examination of the mechanisms by which friends and friendship networks influence nutrition and physical activity behaviors and weight gain in the transition to college life. The SPARC study aims to follow 1450 university freshmen from a large university over an academic year, collecting data on multiple aspects of friends and friendship networks. Integrating multiple types of data related to student lives, ecological momentary assessments (EMAs) are administered via a cell phone application, devilSPARC. EMAs collected in four 1-week periods (a total of 4 EMA waves) are integrated with linked data from web-based surveys and anthropometric measurements conducted at four times points (for a total of eight data collection periods including EMAs, separated by ~1 month). University databases will provide student card data, allowing integration of both time-dated data on food purchasing, use of physical activity venues, and geographical information system (GIS) locations of these activities relative to other students in their social networks. Findings are intended to guide the development of more effective interventions to enhance behaviors among college students that protect against weight gain during college.

Present status and future of the sophisticated work station

Science.gov (United States)

Ishida, Haruhisa

The excellency of the work station is explained, by comparing the functions of software and hardware of work station with those of personal computer. As one of the examples utilizing the functions of work station, desk top publishing is explained. By describing the competition between the Group of ATT · Sun Microsystems which intends to have the leadership by integrating Berkeley version which is most popular at this moment and System V version, and the group led by IBM, future of UNIX as OS of work station is predicted. Development of RISC processor, TRON Plan and Sigma Projects by MITI are also mentioned as its background.

The Sun

CERN Document Server

Golub, Leon

2017-01-01

Essential for life on earth and a major influence on our environment, the Sun is also the most fascinating object in the daytime sky. Every day we feel the effect of its coming and going – literally the difference between day and night. But figuring out what the Sun is, what it’s made of, why it glows so brightly, how old it is, how long it will last – all of these take thought and observation. Leon Golub and Jay M. Pasachoff offer an engaging and informative account of what scientists know about the Sun, and the history of these discoveries. Solar astronomers have studied the Sun over the centuries both for its intrinsic interest and in order to use it as a laboratory to reveal the secrets of other stars. The authors discuss the surface of the Sun, including sunspots and their eleven-year cycle, as well as the magnetism that causes them; the Sun’s insides, as studied mainly from seismic waves that astronomers record on its surface; the outer layers of the Sun that we see from Earth only at eclipses ...

SUN1 splice variants, SUN1_888, SUN1_785, and predominant SUN1_916, variably function in directional cell migration

OpenAIRE

Nishioka, Yu; Imaizumi, Hiromasa; Imada, Junko; Katahira, Jun; Matsuura, Nariaki; Hieda, Miki

2016-01-01

The LINC complex is a multifunctional protein complex that is involved in various processes at the nuclear envelope, such as nuclear migration, mechanotransduction and chromatin tethering in the meiotic phase. However, it remains unknown how these functions are regulated in different cell contexts. An inner nuclear membrane component of the LINC complex, SUN1, is ubiquitously expressed. The human SUN1 gene produces over 10 variants by alternative splicing. Although functions of SUN1 are relat...

Sun behaviour in Canadian children: results of the 2006 National Sun Survey.

Science.gov (United States)

Pichora, Erin C; Marrett, Loraine D

2010-01-01

Childhood sun exposure is a particularly important determinant of skin cancer, yet little data are available for children. This paper describes sun behaviour among Canadian children for the summer of 2006. As part of the Second National Sun Survey (NSS2), 1,437 parents reported on the time spent in the sun, and the frequency of sun protection behaviours and sunburning for one of their children aged 1 to 12 years. Analysis was carried out using complex survey procedures in SAS and STATA. The majority of children (94%) spend at least 30 minutes in the sun on a typical summer day; however, regular sun protection is only commonly reported for young children (1 to 5 years) and involves covering their heads and wearing sunscreen (85%). The frequency of other protective behaviours is much lower, and sun protection decreases with age. Older children are also twice as likely to spend extended time in the sun and to get a sunburn. Among older children, boys are more likely to cover their heads and girls are more likely to wear sunscreen. Regular sun protection among Canadian children is low, given their sun exposure. Heavy reliance on sunscreen is consistent with previous reports and indicates that other measures, such as seeking shade and wearing protective clothing, need to be promoted. Riskier sun behaviour among older children may reflect decreased parental control, as well as changing attitudes and peer pressure, and highlights the importance of adult role models and targeted interventions for this age group.

Vitamin D Beliefs and Associations with Sunburns, Sun Exposure, and Sun Protection

Science.gov (United States)

Kim, Bang Hyun; Glanz, Karen; Nehl, Eric J.

2012-01-01

The main objective of this study was to examine certain beliefs about vitamin D and associations with sun exposure, sun protection behaviors, and sunburns. A total of 3,922 lifeguards, pool managers, and parents completed a survey in 2006 about beliefs regarding vitamin D and sun-related behaviors. Multivariate ordinal regression analyses and linear regression analysis were used to examine associations of beliefs and other variables. Results revealed that Non-Caucasian lifeguards and pool managers were less likely to agree that they needed to go out in the sun to get enough vitamin D. Lifeguards and parents who were non-Caucasian were less likely to report that sunlight helped the body to produce vitamin D. A stronger belief about the need to go out in the sun to get enough vitamin D predicted more sun exposure for lifeguards. For parents, a stronger belief that they can get enough vitamin D from foods predicted greater sun protection and a stronger belief that sunlight helps the body produce vitamin D predicted lower sun exposure. This study provides information regarding vitamin D beliefs and their association with certain sun related behaviors across different demographic groups that can inform education efforts about vitamin D and sun protection. PMID:22851950

Sun exposure, sun protection and sunburn among Canadian adults.

Science.gov (United States)

Pinault, Lauren; Fioletov, Vitali

2017-05-17

Ultraviolet radiation (UVR) exposure and a history of sunburn are important risk factors for skin cancer. Sunburn is more common among men, younger age groups, and people in higher income households. Sun protection measures also vary by sex, age, and socioeconomic characteristics. Associations between ambient UVR and sunburn and sun safety measures have not been quantified. A total of 53,130 respondents aged 18 or older answered a Canadian Community Health Survey (CCHS) module on sun safety, which was administered in six provinces from 2005 to 2014. The module contained questions about sunburn, time in the sun, and sun protection. These respondents were linked to an ambient erythemal UVR dataset representing the June-to-August mean. Descriptive statistics and logistic regression were used to examine associations between population characteristics, sunburn, sun safety, time in the sun, and ambient UVR. Sunburn was reported by 33% of respondents and was more common among men, younger age groups, people who were not members of visible minorities, residents of higher income households, and individuals who were employed. On a typical summer day, a larger percentage of women than men sought shade and wore sunscreen, whereas a larger percentage of men wore a hat or long pants. As ambient summer UVR increased, women were more likely to apply sunscreen to their face, seek shade, or wear a hat (OR~1.02 to 1.09 per increase of 187 J/m² of erythemally-weighted UVR, or 5.4% of the mean); these associations were not observed among men. Findings related to sunburn and sun protection were similar to those of previous studies. The association between ambient UVR and women's precautionary measures suggests that information about UVR may influence their decision to protect their skin.

Our turbulent sun

International Nuclear Information System (INIS)

Frazier, K.

1982-01-01

The quest for a new understanding of the sun and its surprising irregularities, variations, and effects is described. Attention is given to the sun's impact on life on earth, the weather and geomagnetic storms, sunspots, solar oscillations, the missing neutrinos in the sun, the 'shrinking sun', the 'dance' of the orbits, and the search for the 'climate connection'. It is noted that the 1980s promise to be the decade of the sun: not only because solar power may be a crucial ingredient in efforts to solve the energy crisis, but also because there will be brilliant auroras over North America, because sunspot activity will be the second highest since the 17th century, and because an unmanned spacecraft (i.e., the solar polar mission) will leave the plane of the solar system and observe the sun from above and below

The star ''Sun''

International Nuclear Information System (INIS)

Pecker, J.-C.

1982-01-01

The author gives a resume of our knowledge of the Sun. In particular, he discusses the mass, luminosity and chemical composition of the Sun, and then asks what an observer from Sirius would think about the Sun. (G.T.H.)

Coherent states related with SU(N) and SU(N,1) groups

International Nuclear Information System (INIS)

Gitman, D.M.; Shelepin, A.L.

1990-01-01

The basis of coherent state (CS) for symmetric presentations of groups SU(N) and SU(N,1) is plotted, its properties being investigated. Evolution of CS is considered. Relation between CS of groups SU(N) and Glauber is ascertained

Sun exposure and sun protection practices of children and their parents.

LENUS (Irish Health Repository)

Kiely, A D

2009-05-01

The primary aims of this study were: to estimate sun exposure in hours of children in Cork during the summer months; to examine sun protection measures used by children and their parents and to explore parental knowledge of sun exposure and protection. A cross-sectional study, using a semi-structured questionnaire, was conducted in June 2006 in primary schools, pre-schools and creches throughout Cork City and County. Parents of 250 children aged less than 12 years were sampled. Mean sun exposure of Cork children was 40.9 hours per week in the summer months, with 77 (46.1%) children developing sunburn. 59.3% of the studied children were of skin type 1 or 2. 95 (57%) children on weekdays and 137 (82%) children at weekends were exposed to the sun between 11 am and 3 pm. Sunscreen and hats\\/caps were the most common protection measures used. A minority used protective clothing, sunglasses or sought shade. Thirty one (30.5%) children had sunscreen reapplied every 2 hours. Knowledge of sun protection was considerable among Irish parents. However the frequency of sunburn among Irish children suggests we are not providing them with adequate sun protection.

Sun Safety

Science.gov (United States)

... Children from the Sun? Are There Benefits to Spending Time Outdoors? The Surgeon General’s Call to Action to Prevent Skin Cancer Related Resources Sun Safety Tips for Men Tips for Families Tips for Schools Tips for Employers Tips for ...

SOHO reveals violent action on the quiet Sun

Science.gov (United States)

1996-05-01

SOHO's scientists are impressed by the vigorous action that they see going on every day, because the Sun is in the very quietest phase of its eleven-year cycle of activity. To ground-based observatories it appears extremely calm just now. The early indications of SOHO's performance amply justify the creation of a sungazing spacecraft capable of observing ultraviolet emissions that are blotted out by the Earth's atmosphere. Apart from the imager, two ultraviolet spectrometers and an ultraviolet coronagraph (an imager for the outer atmosphere) are busy analysing the violent processes at a wide range of wavelengths. Between them, these instruments should cure long-lasting ignorance concerning the Sun, especially about why the atmosphere is so hot and what drives the solar wind that blows non-stop into the Solar System. Scientists from other experimental teams use SOHO to explore the Sun from its deep interior to the far reaches of the solar wind. They have watched the supposedly quiet Sun belching huge masses of gas into space. They have mapped a hole burnt by the solar wind in a breeze of gas coming from the stars. And they have detected currents of gas flowing just below the visible surface. SOHO is a project of international cooperation between the European Space Agency and NASA. The spacecraft was built in Europe and instrumented by scientists on both sides of the Atlantic. NASA launched SOHO on 2 December 1995, and also provides the ground stations and an operations centre near Washington. The first results are the more remarkable because SOHO arrived at its vantage point 1,500,000 kilometres out in space only in February, and formally completed its commissioning on 16 April. It has a long life ahead of it. All scientific instruments are working well. The luminosity oscillation imager belonging to the VIRGO experiment had trouble with its lens cover. When opened, the cover rebounded on its hinges and closed again. Commands were devised that gave a shorter impulse

Sun Protection Practices and Sun Exposure among Children with a Parental History of Melanoma

Science.gov (United States)

Glenn, Beth A.; Lin, Tiffany; Chang, L. Cindy; Okada, Ashley; Wong, Weng Kee; Glanz, Karen; Bastani, Roshan

2014-01-01

Background First-degree relatives of melanoma survivors have a substantially higher lifetime risk for melanoma than individuals with no family history. Exposure to ultraviolet radiation is the primary modifiable risk factor for the disease. Reducing UV exposure through sun protection may be particularly important for children with a parental history of melanoma. Nonetheless, limited prior research has investigated sun protection practices and sun exposure among these children. Methods The California Cancer Registry was used to identify melanoma survivors eligible to participate in a survey to assess their children's sun protection practices and sun exposure. The survey was administered by mail, telephone, or web to Latino and non-Latino white melanoma survivors with at least one child (0–17 years; N = 324). Results Sun exposure was high and the rate of sunburn was equivalent to or higher than estimates from average risk populations. Use of sun protection was suboptimal. Latino children were less likely to wear sunscreen and hats and more likely to wear sunglasses, although these differences disappeared in adjusted analyses. Increasing age of the child was associated with lower sun protection and higher risk for sunburn whereas higher objective risk for melanoma predicted improved sun protection and a higher risk for sunburns. Perception of high barriers to sun protection was the strongest modifiable correlate of sun protection. Conclusions Interventions to improve sun protection and reduce sun exposure and sunburns in high risk children are needed. Impact Intervening in high risk populations may help reduce the burden of melanoma in the U.S. PMID:25587110

baonan sun

Indian Academy of Sciences (India)

Home; Journals; Pramana – Journal of Physics. BAONAN SUN. Articles written in Pramana – Journal of Physics. Volume 90 Issue 2 February 2018 pp 23 Research Article. Rogue waves in the multicomponent Mel'nikov system and multicomponent Schrödinger–Boussinesq system · BAONAN SUN ZHAN LIAN.

Fengrui Sun

Indian Academy of Sciences (India)

Home; Journals; Sadhana. Fengrui Sun. Articles written in Sadhana. Volume 34 Issue 5 October 2009 pp 851-864. Profit rate performance optimization for a generalized irreversible combined refrigeration cycle · Kang Ma Lingen Chen Fengrui Sun · More Details Abstract Fulltext PDF. Finite-time exergoeconomic ...

Sunburn, sun exposure, and sun sensitivity in the Study of Nevi in Children.

Science.gov (United States)

Satagopan, Jaya M; Oliveria, Susan A; Arora, Arshi; Marchetti, Michael A; Orlow, Irene; Dusza, Stephen W; Weinstock, Martin A; Scope, Alon; Geller, Alan C; Marghoob, Ashfaq A; Halpern, Allan C

2015-11-01

To examine the joint effect of sun exposure and sunburn on nevus counts (on the natural logarithm scale; log nevi) and the role of sun sensitivity. We describe an analysis of cross-sectional data from 443 children enrolled in the prospective Study of Nevi in Children. To evaluate the joint effect, we partitioned the sum of squares because of interaction between sunburn and sun exposure into orthogonal components representing (1) monotonic increase in log nevi with increasing sun exposure (rate of increase of log nevi depends on sunburn), and (2) nonmonotonic pattern. In unadjusted analyses, there was a marginally significant monotonic pattern of interaction (P = .08). In adjusted analyses, sun exposure was associated with higher log nevi among those without sunburn (P sunburn (P = .14). Sunburn was independently associated with log nevi (P = .02), even though sun sensitivity explained 29% (95% confidence interval: 2%-56%, P = .04) of its effect. Children with high sun sensitivity and sunburn had more nevi, regardless of sun exposure. A program of increasing sun protection in early childhood as a strategy for reducing nevi, when applied to the general population, may not equally benefit everyone. Copyright © 2015 Elsevier Inc. All rights reserved.

Creating a Sun-Safe Camp.

Science.gov (United States)

Landrey, Ann

1996-01-01

Strategies for minimizing sun exposure of campers and staff include educating campers about the sun's effect on their skin, scheduling activities when the sun is less intense, creating shade at the camp site, incorporating sun protection into camp dress code, and training staff regarding sun protection. Addresses OSHA and liability issues. (LP)

SunBlock '99: Young Scientists Investigate the Sun

Science.gov (United States)

Walsh, R. W.; Pike, C. D.; Mason, H.; Young, P.; Ireland, J.; Galsgaard, K.

1999-10-01

SunBlock `99 is a Web-based Public Understanding of Science and educational project which seeks to present the very latest solar research as seen through the eyes of young British scientists. These ``solar guides'' discuss not only their scientific interests, but also their extra-curricular activities and the reasons they chose scientific careers; in other words the human face of scientific research. The SunBlock '99 pages gather a range of solar images and movies from current solar space observatories and discuss the underlying physics and its relationship to the school curriculum. The instructional level is pitched at UK secondary school children (aged 13-16 years). It is intended that the material should not only provide a visually appealing introduction to the study of the Sun, but that it should help bridge the often wide gap between classroom science lessons and the research scientist `out in the field'. SunBlock '99 is managed by a team from the Rutherford Appleton Laboratory and the Universities of St Andrews and Cambridge, together with educational consultants. The production has, in part, been sponsored by PPARC and the Millennium Mathematics Project. Web site addresss: http://www.sunblock99.org.uk

Machine vision inspection of lace using a neural network

Science.gov (United States)

Sanby, Christopher; Norton-Wayne, Leonard

1995-03-01

Lace is particularly difficult to inspect using machine vision since it comprises a fine and complex pattern of threads which must be verified, on line and in real time. Small distortions in the pattern are unavoidable. This paper describes instrumentation for inspecting lace actually on the knitting machine. A CCD linescan camera synchronized to machine motions grabs an image of the lace. Differences between this lace image and a perfect prototype image are detected by comparison methods, thresholding techniques, and finally, a neural network (to distinguish real defects from false alarms). Though produced originally in a laboratory on SUN Sparc work-stations, the processing has subsequently been implemented on a 50 Mhz 486 PC-look-alike. Successful operation has been demonstrated in a factory, but over a restricted width. Full width coverage awaits provision of faster processing.

4 MW upgrade to DIII-D FWCD system: System commissioning and initial operation

International Nuclear Information System (INIS)

Cary, W.P.; Callis, R.W.; deGrassie, J.S.; Harris, T.E.; O'Neill, R.C.; Pinsker, R.I.; Baity, F.W.; Barber, G.C.; Ferguson, S.W.

1995-01-01

The initial installation of the 4 MW fast wave current drive (FWCD) upgrade started in 1992 with the purchase of two ABB/Thomcast AG rf power amplifiers. These amplifiers cover the frequency range 30 MHz to 120 MHz. A maximum output power of over 2 MW between 30 MHz and 80 MHz and 1 MW at 120 MHz were the specification requirements. The system as installed is comprised of the two mentioned rf amplifiers, coaxial transmission and matching components, rf phase and amplitude monitoring, and a SUN SparcStation 10 control system. Due to various reasons almost every major component in the system required redesign and engineering in order to meet the system requirements. The failures, probable cause and the final redesigns will be discussed as well as some thoughts on how better to specify system requirements for future systems

4 MW upgrade to DIII-D FWCD system: System commissioning and initial operation

International Nuclear Information System (INIS)

Cary, W.P.; Callis, R.W.; Grassie, J.S. de; Harris, T.E.; O'Neill, R.C.; Pinsker, R.I.; Baity, F.W.; Barber, G.C.; Ferguson, S.W.

1995-10-01

The initial installation of the 4 MW fast wave current drive (FWCD) upgrade started in 1992 with the purchase of two ABB/Thomcast AG rf power amplifiers. These amplifiers cover the frequency range 30 MHz to 120 MHz. A maximum output power of over 2 MW between 30 MHz and 80 MHz and 1 MW at 120 MHz were the specification requirements. The system as installed is comprised of the two mentioned rf amplifiers, coaxial transmission and matching components, rf phase and amplitude monitoring, and a SUN SparcStation 10 control system. Due to various reasons almost every major component in the system required redesign and engineering in order to meet the system requirements. The failures, probable cause and the final redesigns will be discussed as well as some thoughts on how better to specify system requirements for future systems

SU(N) Irreducible Schwinger Bosons

OpenAIRE

Mathur, Manu; Raychowdhury, Indrakshi; Anishetty, Ramesh

2010-01-01

We construct SU(N) irreducible Schwinger bosons satisfying certain U(N-1) constraints which implement the symmetries of SU(N) Young tableaues. As a result all SU(N) irreducible representations are simple monomials of $(N-1)$ types of SU(N) irreducible Schwinger bosons. Further, we show that these representations are free of multiplicity problems. Thus all SU(N) representations are made as simple as SU(2).

Lifestyle, sun worshipping and sun tanning - what about UV-A sun beds. Livsstil, soling og bruning - hva med UV-A solarier

Energy Technology Data Exchange (ETDEWEB)

Thune, P [Ullevaal Sykehus, Oslo (Norway)

1991-06-01

This article considers the effects of ultraviolet (UV) light from the sun and UV-A sun beds on the skin. Sun worshipping and sun therapy has been en vogue for centuries, but in another way than used today. A changing lifestyle has led to an increase of various skin diseases, including skin cancer. Short wave UV-light (UV-B) in particular has been blamed for inducing not only erythema and pigmentation but also more chronic skin lesions. Long wave UV-light (UV-A) has been shown to be the cause of similar changes to the skin but the pigmentation is of another quality and affords less protection against the harmful effects of UV-B. A concept of sun reactive skin typing has been created. This is based on self-reported responses to an initial exposure to sun as regards tanning ability and erythema reaction. These two factors have certain practical consequences, not only for UV-phototherapy but also for a person's risk of developing skin cancer. Recently, several research groups and dermatologists have discouraged extensive use of UV-A sun beds because of side effects of varying degrees of seriousness. The possible implications of these side effects for the organism are not fully elucidated and may be more profound than known today. The British Photodermatology Group has issued more stringent rules for persons who, despite advice to the contrary, still wish to use UV-A sun beds. 14 refs., 1 tab.

Lifestyle, sun worshipping and sun tanning - what about UV-A sun beds. Livsstil, soling og bruning - hva med UV-A solarier

Energy Technology Data Exchange (ETDEWEB)

Thune, P. (Ullevaal Sykehus, Oslo (Norway))

1991-06-01

This article considers the effects of ultraviolet (UV) light from the sun and UV-A sun beds on the skin. Sun worshipping and sun therapy has been en vogue for centuries, but in another way than used today. A changing lifestyle has led to an increase of various skin diseases, including skin cancer. Short wave UV-light (UV-B) in particular has been blamed for inducing not only erythema and pigmentation but also more chronic skin lesions. Long wave UV-light (UV-A) has been shown to be the cause of similar changes to the skin but the pigmentation is of another quality and affords less protection against the harmful effects of UV-B. A concept of sun reactive skin typing has been created. This is based on self-reported responses to an initial exposure to sun as regards tanning ability and erythema reaction. These two factors have certain practical consequences, not only for UV-phototherapy but also for a person's risk of developing skin cancer. Recently, several research groups and dermatologists have discouraged extensive use of UV-A sun beds because of side effects of varying degrees of seriousness. The possible implications of these side effects for the organism are not fully elucidated and may be more profound than known today. The British Photodermatology Group has issued more stringent rules for persons who, despite advice to the contrary, still wish to use UV-A sun beds. 14 refs., 1 tab.

Sun protection counseling by pediatricians has little effect on parent and child sun protection behavior.

Science.gov (United States)

Cohen, Liza; Brown, Judith; Haukness, Heather; Walsh, Lori; Robinson, June K

2013-02-01

To compare counseling concerning sun protection and outdoor exercise with the parent's report of the behavior of a child aged 9-16 years old. Structured interviews of medical personnel in 3 Chicago area practices elicited information about counseling methods and recommendations. In each practice, a convenience sample of parents completed a self-reported survey of their and their child's behavior. Sun protection counseling occurred more frequently than exercise counseling in all practices (P = .014). Sun protection counseling was associated with parental prompting (P = .004), performing a summer camp physical (P = .002), and the child having a sunburn (P = .003). After controlling for the child's age, sex, and skin tone, sun protection counseling was not associated with the child's use of sun protection. In multivariate analysis of the child's sun protection behavior, parental sunburns, indoor tanning in the last 12 months, perception of skin cancer risk, and sun protection self-efficacy were significant (P = .02). Children who pursued outdoor sports were twice as likely to use inadequate sun protection and sustain sunburns (CI 1.3-1.7). The child's sun protection behavior was influenced by parental sun protection, parental perception of skin cancer risk, and parental sun protection self-efficacy; therefore, sun protection for children needs to be aimed at parents as well as children. Communication with parents in a way that incorporates the principles of motivational interviewing may be more effective in promoting behavioral change than admonitions to use sunscreen. Copyright © 2013 Mosby, Inc. All rights reserved.

Work-time sun behaviours among Canadian outdoor workers: results from the 2006 National Sun Survey.

Science.gov (United States)

Marrett, Loraine D; Pichora, Erin C; Costa, Michelle L

2010-01-01

The objective of the study was to describe summer work-related sun behaviours among Canadian outdoor workers. Information on time in the sun and sun protection practices at work during the summer of 2006 were collected from 1,337 outdoor workers aged 16-64 years as part of the Second National Sun Survey. Proportions (and 95% confidence intervals) were estimated using procedures appropriate for complex survey designs. Twenty-six percent of all Canadians, 39% of males and 33% of those aged 16-24 years work outdoors during the summer. Although 41% spend four or more hours daily in the sun at work, just over half always or often protect themselves by covering their heads (58%), wearing protective clothing (56%) or wearing sunglasses (54%), and only 29% use sunscreen. Males and those aged 16-24 spend the most work time in the sun but are the least likely to use protection. The prevalence of outdoor work and sun behaviours varies among regions. Study findings confirm the need for strategies to reduce time in the sun and increase the use of sun protection among outdoor workers. In order to be effective, these strategies must include both enhanced workplace policies and practice, and increased individual use of sun protection.

Sun exposure and sun protection behaviours among young adult sport competitors.

Science.gov (United States)

Lawler, Sheleigh; Spathonis, Kym; Eakin, Elizabeth; Gallois, Cindy; Leslie, Eva; Owen, Neville

2007-06-01

To explore the relationship between sun protection and physical activity in young adults (18-30 years) involved in four organised sports. Participants (n=237) in field hockey, soccer, tennis and surf sports completed a self-administered survey on demographic and sun-protective behaviours while playing sport. Differences in sun-protective behaviour were explored by sport and by gender. Sunburn during the previous sporting season was high (69%). There were differences between sports for sunburn, sunscreen use and reapplication of sunscreen. Lifesaving had the highest rates compared with the other three sports. Hats and sunglasses worn by participants varied significantly by sports. A greater proportion of soccer and hockey players indicated they were not allowed to wear a hat or sunglasses during competition. For all sports, competition was played mainly in the open with no shade provision for competitors while they were playing. There were some gender differences within each of the sports. Female soccer and tennis players were more likely to wear sunscreen compared with males. Female hockey players were more likely to wear a hat compared with males. Our findings highlight that there is still room for improvement in sun-protective behaviours among young adult sport competitors. There is a need for a systematic approach to sun protection in the sporting environments of young adults. Health promotion efforts to increase physical activity need to be paired with sun protection messages.

MedSun Reports

Data.gov (United States)

U.S. Department of Health & Human Services — The Medical Product Safety Network (MedSun) is an adverse event reporting program launched in 2002. The primary goal for MedSun is to work collaboratively with the...

Seasons by the Sun

Science.gov (United States)

Stark, Meri-Lyn

2005-01-01

Understanding the Sun has challenged people since ancient times. Mythology from the Greek, Inuit, and Inca cultures attempted to explain the daily appearance and nightly disappearance of the Sun by relating it to a chariot being chased across the sky. While people no longer believe the Sun is a chariot racing across the sky, teachers are still…

Sun-Earth Scientists and Native Americans Collaborate on Sun-Earth Day

Science.gov (United States)

Ng, C. Y.; Lopez, R. E.; Hawkins, I.

2004-12-01

Sun-Earth Connection scientists have established partnerships with several minority professional societies to reach out to the blacks, Hispanics and Native American students. Working with NSBP, SACNAS, AISES and NSHP, SEC scientists were able to speak in their board meetings and national conferences, to network with minority scientists, and to engage them in Sun-Earth Day. Through these opportunities and programs, scientists have introduced NASA research results as well indigenous views of science. They also serve as role models in various communities. Since the theme for Sun-Earth Day 2005 is Ancient Observatories: Timeless Knowledge, scientists and education specialists are hopeful to excite many with diverse backgrounds. Sun-Earth Day is a highly visible annual program since 2001 that touches millions of students and the general public. Interviews, classroom activities and other education resources are available on the web at sunearthday.nasa.gov.

Guaranteeing Pointing Performance of the SDO Sun-Pointing Controllers in Light of Nonlinear Effects

Science.gov (United States)

Starin, Scott R.; Bourkland, Kristin L.

2007-01-01

The Solar Dynamics Observatory (SDO) mission is the first Space Weather Research Network mission, part of NASA s Living With a Star program.1 This program seeks to understand the changing Sun and its effects on the Solar System, life, and society. To this end, the SDO spacecraft will carry three Sun-observing instruments to geosynchronous orbit: Helioseismic and Magnetic Imager (HMI), led by Stanford University; Atmospheric Imaging Assembly (AIA), led by Lockheed Martin Space and Astrophysics Laboratory; and Extreme Ultraviolet Variability Experiment (EVE), led by the University of Colorado. Links describing the instruments in detail may be found through the SDO web site.2 The basic mission goals are to observe the Sun for a very high percentage of the 5-year mission (10-year goal) with long stretches of uninterrupted observations and with constant, high-data-rate transmission to a dedicated ground station. These goals guided the design of the spacecraft bus that will carry and service the three-instrument payload. At the time of this publication, the SDO spacecraft bus is well into the integration and testing phase at the NASA Goddard Space Flight Center (GSFC). A three-axis stabilized attitude control system (ACS) is needed both to point at the Sun accurately and to keep the roll about the Sun vector correctly positioned. The ACS has four reaction wheel modes and 2 thruster actuated modes. More details about the ACS in general and the control modes in particular can be found in Refs. [3-6]. All four of SDO s wheel-actuated control modes involve Sun-pointing controllers, as might be expected from such a mission. Science mode, during which most science data is collected, uses specialized guide telescopes to point accurately at the Sun. Inertial mode has two sub-modes, one tracks a Sun-referenced target orientation, and another maintains an absolute (star-referenced) target orientation, that both employ a Kalman filter to process data from a digital Sun sensor and

A practical equation of state for the sun and sun-like stars

International Nuclear Information System (INIS)

Lin, H.H.; Daeppen, W.

2012-01-01

For models of the Sun and Sun-like stars, a high-quality equation of state is crucial. Conversely, helio- and asteroseismological observations put constraints on the physical formalisms. They effectively turn the Sun and stars into laboratories for dense plasmas. For models of the Sun and Sun-like stars, the most accurate equation of state so far has been the one developed as part of OPAL opacity project of Livermore. However, the OPAL equation of state is limited in two important respects. First, it is only available in the form of pre-computed tables that are provided from Lawrence Livermore National Laboratory. Applications to stellar modeling require therefore interpolation, with unavoidable loss of accuracy. Second, the OPAL equation of state is proprietary and not freely available. Varying its underlying physical parameters is therefore no option for the community. We report on the most recent progress with the development of a high-precision emulation of the OPAL equation of state that will lead to an in-line tool for modelers (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Child sun protection: sun-related attitudes mediate the association between children's knowledge and behaviours.

Science.gov (United States)

Wright, Caradee; Reeder, Anthony I; Gray, Andrew; Cox, Brian

2008-12-01

To describe and investigate the relationship among the sun-related knowledge, attitudes and behaviours of New Zealand primary schoolchildren and consider the roles of sex and school year level. A randomly selected, two-stage cluster sample of 488 children from 27 primary schools in five regions of New Zealand was surveyed regarding their sun-related knowledge, attitudes and behaviours. A scoring system was used to assign a knowledge, attitude and behaviour score to each child. Although knowledge increased with school year level, there was a decline in sun protective attitudes and behaviours. There was little variation in knowledge, attitudes and behaviour between boys and girls, but sex-year level interactions were found for knowledge and behaviour. When considering children's knowledge, attitudes and behaviours simultaneously, knowledge was only significantly associated with behaviours when mediated by attitudes. When targeting child sun protection and skin cancer prevention programmes, a focus on attitudes towards sun exposure and a suntan may prove beneficial in influencing sun-related behaviours.

Environmental variables associated with vacationers' sun protection at warm weather resorts in North America

International Nuclear Information System (INIS)

Andersen, Peter A.; Buller, David B.; Walkosz, Barbara J.; Scott, Michael D.; Beck, Larry; Liu, Xia; Abbott, Allison; Eye, Rachel

2016-01-01

Background: Vacationing at sunny, warm weather locations is a risk factor for excessive solar ultraviolet (UV) radiation exposure and skin cancer. Objectives: This study examined the association of environmental variables related to UV levels with vacationers' sun protection. Methods: Vacationers at 41 summer resorts in 17 states and 1 Canadian Province were interviewed (n=3531) and observed (N=4347) during 2012 and 2013. Clothing coverage, sunglasses, and shade use were observed. Use of sunscreen and sunburns were self-reported. Environmental information was recorded by research staff or acquired from ground stations and the weather service. Results: Temperature was positively associated with sun protection behaviors; however clothing coverage was negatively associated with temperature. Cloud cover was negatively associated with sun protection, with the exception of clothing coverage which was positively associated with it. Elevation showed a mixed pattern of associations with vacationer's sun protection. Latitude of a resort was negatively associated with most sun protection behaviors, such that sun protection increased at more southerly resorts. Similarly, the farther south a vacationer traveled to the resort, the less sun protection they employed. The UV index showed a weak, positive relationship with some sun protection behaviors even when controlling for temperature. Conclusions: Vacationers appeared aware that UV is higher at southern latitudes and may learn UV is intense when living in southern regions. However, many used temperature, an unreliable cue, to judge UV intensity and seemed to adjust clothing for warmth not UV protection. Efforts are needed to help individuals make more accurate sun safety decisions. - Highlights: • Vacationers poorly monitor and protect against environmental ultraviolet radiation (UVR). • On cloudy days vacationers fail to protect against UVR. • Temperature is erroneously used by vacationers as a marker for UVR

Environmental variables associated with vacationers' sun protection at warm weather resorts in North America

Energy Technology Data Exchange (ETDEWEB)

Andersen, Peter A., E-mail: westone47@gmail.com [School of Communication, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States); Buller, David B.; Walkosz, Barbara J. [Klein Buendel, Inc., 1667 Cole Boulevard, Suite 225, Golden, CO 80401 (United States); Scott, Michael D. [Mikonics, Inc., 40 B Old Road South, Santa Fe, NM 87540 (United States); Beck, Larry [L. Robert Payne School of Hospitality and Tourism Management, San Diego State University, Room PSFA 445, San Diego, CA 92182 (United States); Liu, Xia [Klein Buendel, Inc., 1667 Cole Boulevard, Suite 225, Golden, CO 80401 (United States); Abbott, Allison [School of Communication, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States); Eye, Rachel [Klein Buendel, Inc., 1667 Cole Boulevard, Suite 225, Golden, CO 80401 (United States)

2016-04-15

Background: Vacationing at sunny, warm weather locations is a risk factor for excessive solar ultraviolet (UV) radiation exposure and skin cancer. Objectives: This study examined the association of environmental variables related to UV levels with vacationers' sun protection. Methods: Vacationers at 41 summer resorts in 17 states and 1 Canadian Province were interviewed (n=3531) and observed (N=4347) during 2012 and 2013. Clothing coverage, sunglasses, and shade use were observed. Use of sunscreen and sunburns were self-reported. Environmental information was recorded by research staff or acquired from ground stations and the weather service. Results: Temperature was positively associated with sun protection behaviors; however clothing coverage was negatively associated with temperature. Cloud cover was negatively associated with sun protection, with the exception of clothing coverage which was positively associated with it. Elevation showed a mixed pattern of associations with vacationer's sun protection. Latitude of a resort was negatively associated with most sun protection behaviors, such that sun protection increased at more southerly resorts. Similarly, the farther south a vacationer traveled to the resort, the less sun protection they employed. The UV index showed a weak, positive relationship with some sun protection behaviors even when controlling for temperature. Conclusions: Vacationers appeared aware that UV is higher at southern latitudes and may learn UV is intense when living in southern regions. However, many used temperature, an unreliable cue, to judge UV intensity and seemed to adjust clothing for warmth not UV protection. Efforts are needed to help individuals make more accurate sun safety decisions. - Highlights: • Vacationers poorly monitor and protect against environmental ultraviolet radiation (UVR). • On cloudy days vacationers fail to protect against UVR. • Temperature is erroneously used by vacationers as a marker for UVR

SUN-RAH: a nucleoelectric BWR university simulator based in reduced order models; SUN-RAH: simulador universitario de nucleoelectrica BWR basado en modelos de orden reducido

Energy Technology Data Exchange (ETDEWEB)

Morales S, J.B.; Lopez R, A.; Sanchez B, A.; Sanchez S, R.; Hernandez S, A. [DEPFI, Campus Morelos, en IMTA Jiutepec, Morelos (Mexico)]. e-mail: jms0620@yahoo.com

2003-07-01

The development of a simulator that allows to represent the dynamics of a nucleo electric central, with nuclear reactor of the BWR type, using reduced order models is presented. These models present the characteristics defined by the dominant poles of the system (1) and most of those premature operation transitories in a power station can be reproduced with considerable fidelity if the models are identified with data of plant or references of a code of better estimate like RAMONA, TRAC (2) or RELAP. The models of the simulator are developments or own simplifications starting from the physical laws and retaining the main terms. This work describes the objective of the project and the general specifications of the University student of Nucleo electric simulator with Boiling Water Reactor type (SUN-RAH) as well as the finished parts that fundamentally are the nuclear reactor, the one of steam supply (NSSS), the plant balance (BOP), the main controllers of the plant and the implemented graphic interfaces. The pendent goals as well as the future developments and applications of SUN-RAH are described. (Author)

Totality eclipses of the Sun

CERN Document Server

Littmann, Mark; Willcox, Ken

2008-01-01

A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. - ;A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. Totality: Eclipses of the Sun is the best guide and reference book on solar eclipses ever written. It explains: how to observe them; how to photograph and videotape them; why they occur; their history and mythology; and future eclipses - when and where to see them. Totality also tells the remarkable story of how eclipses shocked scientists, revealed the workings of the Sun, and made Einstein famous. And the book shares the experiences and advice of many veteran eclipse observers. Totality: Eclipses of the Sun is profusely ill...

Sun's dynamics and nucleosynthesis

International Nuclear Information System (INIS)

Gavanescu, Adela; Rusu, Mircea V.

2005-01-01

Nucleosynthesis processes in the sun are one of the main results related to the evolution of the Sun. Dynamics and energetics of the Sun could be studied indirectly by their elements products in produced by nucleosynthesis. Also solar atmosphere and its characteristics reveled in its full development is observed during the solar eclipses. We try to correlate these facts in order to obtained data to be used in solar models. (authors)

Kug Sun Hong

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. Kug Sun Hong. Articles written in Bulletin of Materials Science. Volume 33 Issue 1 February 2010 pp 43-47 Composites. Microstructure and mechanical properties of Mg–HAP composites · Asit Kumar Khanra Hwa Chul Jung Seung Hoon Yu Kug Sun Hong Kwang Seon Shin.

Status of the C-band RF System for the SPARC-LAB high brightness photo-injector

CERN Document Server

Boni, R.; Bellaveglia, M.; Di Pirro, G.; Ferrario, M.; Gallo, A.; Spataro, B.; Mostacci, A.; Palumbo, L.

2013-01-01

The high brightness photo-injector in operation at the SPARC-LAB facility of the INFN-LNF, Italy, consists of a 150 MeV S-band electron accelerator aiming to explore the physics of low emittance high peak current electron beams and the related technology. Velocity bunching techniques, SASE and Seeded FEL experiments have been carried out successfully. To increase the beam energy so improving the performances of the experiments, it was decided to replace one S-band travelling wave accelerating cavity, with two C-band cavities that allow to reach higher energy gain per meter. The new C-band system is in advanced development phase and will be in operation early in 2013. The main technical issues of the C-band system and the R&D activities carried out till now are illustrated in detail in this paper.

Orbit-attitude coupled motion around small bodies: Sun-synchronous orbits with Sun-tracking attitude motion

Science.gov (United States)

Kikuchi, Shota; Howell, Kathleen C.; Tsuda, Yuichi; Kawaguchi, Jun'ichiro

2017-11-01

The motion of a spacecraft in proximity to a small body is significantly perturbed due to its irregular gravity field and solar radiation pressure. In such a strongly perturbed environment, the coupling effect of the orbital and attitude motions exerts a large influence that cannot be neglected. However, natural orbit-attitude coupled dynamics around small bodies that are stationary in both orbital and attitude motions have yet to be observed. The present study therefore investigates natural coupled motion that involves both a Sun-synchronous orbit and Sun-tracking attitude motion. This orbit-attitude coupled motion enables a spacecraft to maintain its orbital geometry and attitude state with respect to the Sun without requiring active control. Therefore, the proposed method can reduce the use of an orbit and attitude control system. This paper first presents analytical conditions to achieve Sun-synchronous orbits and Sun-tracking attitude motion. These analytical solutions are then numerically propagated based on non-linear coupled orbit-attitude equations of motion. Consequently, the possibility of implementing Sun-synchronous orbits with Sun-tracking attitude motion is demonstrated.

Autonomous Sun-Direction Estimation Using Partially Underdetermined Coarse Sun Sensor Configurations

Science.gov (United States)

O'Keefe, Stephen A.

In recent years there has been a significant increase in interest in smaller satellites as lower cost alternatives to traditional satellites, particularly with the rise in popularity of the CubeSat. Due to stringent mass, size, and often budget constraints, these small satellites rely on making the most of inexpensive hardware components and sensors, such as coarse sun sensors (CSS) and magnetometers. More expensive high-accuracy sun sensors often combine multiple measurements, and use specialized electronics, to deterministically solve for the direction of the Sun. Alternatively, cosine-type CSS output a voltage relative to the input light and are attractive due to their very low cost, simplicity to manufacture, small size, and minimal power consumption. This research investigates using coarse sun sensors for performing robust attitude estimation in order to point a spacecraft at the Sun after deployment from a launch vehicle, or following a system fault. As an alternative to using a large number of sensors, this thesis explores sun-direction estimation techniques with low computational costs that function well with underdetermined sets of CSS. Single-point estimators are coupled with simultaneous nonlinear control to achieve sun-pointing within a small percentage of a single orbit despite the partially underdetermined nature of the sensor suite. Leveraging an extensive analysis of the sensor models involved, sequential filtering techniques are shown to be capable of estimating the sun-direction to within a few degrees, with no a priori attitude information and using only CSS, despite the significant noise and biases present in the system. Detailed numerical simulations are used to compare and contrast the performance of the five different estimation techniques, with and without rate gyro measurements, their sensitivity to rate gyro accuracy, and their computation time. One of the key concerns with reducing the number of CSS is sensor degradation and failure. In

F F Sun

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. F F Sun. Articles written in Bulletin of Materials Science. Volume 37 Issue 1 February 2014 pp 71-76. Study of electroless copper plating on ABS resin surface modified by heterocyclic organosilane self-assembled film · H N Zhang J Wang F F Sun D Liu H Y Wang F Wang.

Skin Cancer-Sun Knowledge and Sun Protection Behaviors of Liver Transplant Recipients in Turkey.

Science.gov (United States)

Haney, Meryem Ozturk; Ordin, Yaprak Sarigol; Arkan, Gulcihan

2017-09-08

The aim of this study was to compare liver transplant recipients (LTRs) with the general population regarding their knowledge of skin cancer, sun health, sun protection behaviors, and affecting factors. This cross-sectional study was conducted in Turkey between March 2016 and September 2016 with 104 LTRs and 100 participants from the general population group (GPG). The mean age of the LTRs was 53.2 ± 11.8 and that of the GPG was 42.7 ± 14.5. The LTRs' skin cancer and sun knowledge were significantly lower than in the GPG, but there was no difference between the two groups in terms of their sun protection behavior scores. The most commonly used sun protection behaviors of LTRs were not being outside and not sunbathing between 10 a.m. and 4 p.m., wearing clothing that covers the skin, and avoiding the solarium. Behaviors commonly practiced by the GPG were wearing sunglasses, wearing sunscreen with a sun protection factor of 15 or higher before going outside, wearing sunscreen at the beach, while swimming or doing physical activity outside, and reapplying it every 2 h. Results of our study will contribute to the development of education and training programs for LTRs on skin cancer. The results also demonstrated the importance of practicing adequate sun protection behaviors which will certainly impact their future health.

SPARC/osteonectin, an endogenous mechanism for targeting albumin to the blood-cerebrospinal fluid interface during brain development

DEFF Research Database (Denmark)

Liddelow, S A; Dziegielewska, K M; Møllgård, K

2011-01-01

Specialized populations of choroid plexus epithelial cells have previously been shown to be responsible for the transfer of individual plasma proteins from blood to the cerebrospinal fluid (CSF), contributing to their characteristically high concentrations in CSF of the developing brain. The mech......Specialized populations of choroid plexus epithelial cells have previously been shown to be responsible for the transfer of individual plasma proteins from blood to the cerebrospinal fluid (CSF), contributing to their characteristically high concentrations in CSF of the developing brain....... The mechanism of this protein transfer remains elusive. Using a marsupial, Monodelphis domestica, we demonstrate that the albumin-binding protein SPARC (osteonectin/BM-40/culture-shock protein) is present in a subset of choroid plexus epithelial cells from its first appearance, throughout development...

SunShot Initiative Portfolio Book 2014

Energy Technology Data Exchange (ETDEWEB)

Solar Energy Technologies Office

2014-05-01

The 2014 SunShot Initiative Portfolio Book outlines the progress towards the goals outlined in the SunShot Vision Study. Contents include overviews of each of SunShot’s five subprogram areas, as well as a description of every active project in the SunShot’s project portfolio as of May 2014.

School Sun-Protection Policies--Does Being SunSmart Make a Difference?

Science.gov (United States)

Turner, Denise; Harrison, Simone L.; Buettner, Petra; Nowak, Madeleine

2014-01-01

Evaluate the comprehensiveness of primary school sun-protection policies in tropical North Queensland, Australia. Pre-determined criteria were used to assess publicly available sun-protection policies from primary schools in Townsville (latitude 19.3°S; n = 43), Cairns (16.9°S; n = 46) and the Atherton Tablelands (17.3°S; n = 23) during 2009-2012.…

Sun-Direction Estimation Using a Partially Underdetermined Set of Coarse Sun Sensors

Science.gov (United States)

O'Keefe, Stephen A.; Schaub, Hanspeter

2015-09-01

A comparison of different methods to estimate the sun-direction vector using a partially underdetermined set of cosine-type coarse sun sensors (CSS), while simultaneously controlling the attitude towards a power-positive orientation, is presented. CSS are commonly used in performing power-positive sun-pointing and are attractive due to their relative inexpensiveness, small size, and reduced power consumption. For this study only CSS and rate gyro measurements are available, and the sensor configuration does not provide global triple coverage required for a unique sun-direction calculation. The methods investigated include a vector average method, a combination of least squares and minimum norm criteria, and an extended Kalman filter approach. All cases are formulated such that precise ground calibration of the CSS is not required. Despite significant biases in the state dynamics and measurement models, Monte Carlo simulations show that an extended Kalman filter approach, despite the underdetermined sensor coverage, can provide degree-level accuracy of the sun-direction vector both with and without a control algorithm running simultaneously. If no rate gyro measurements are available, and rates are partially estimated from CSS, the EKF performance degrades as expected, but is still able to achieve better than 10∘ accuracy using only CSS measurements.

The flight over the sun

International Nuclear Information System (INIS)

Ducrocq, A.

1985-01-01

With the ''Ulysse'' mission, a satellite is going for the first time to leave the ecliptic plane to observe the sun poles. The ISPM (International Solar Polar Mission) probe will go and visit the sun in passing Jupiter way. Sun pole regions are surmised to play a major role in solar wind production [fr

Study of Λ parameters and crossover phenomena in SU(N) x SU(N) sigma models in two dimensions

International Nuclear Information System (INIS)

Shigemitsu, J.; Kogut, J.B.

1981-01-01

The spin system analogues of recent studies of the string tension and Λ parameters of SU(N) gauge theories in 4 dimensions are carried out for the SU(N) x SU(N) and O(N) models in 2 dimensions. The relations between the Λ parameters of both the Euclidean and Hamiltonian formulation of the lattice models and the Λ parameter of the continuum models are obtained. The one loop finite renormalization of the speed of light in the lattice Hamiltonian formulations of the O(N) and SU(N) x SU(N) models is calculated. Strong coupling calculations of the mass gaps of these spin models are done for all N and the constants of proportionality between the gap and the Λ parameter of the continuum models are obtained. These results are contrasted with similar calculations for the SU(N) gauge models in 3+1 dimensions. Identifying suitable coupling constants for discussing the N → infinity limits, the numerical results suggest that the crossover from weak to strong coupling in the lattice O(N) models becomes less abrupt as N increases while the crossover for the SU(N) x SU(N) models becomes more abrupt. The crossover in SU(N) gauge theories also becomes more abrupt with increasing N, however, at an even greater rate than in the SU(N) x SU(N) spin models

The Sun Sense Study: An Intervention to Improve Sun Protection in Children

Science.gov (United States)

Glasser, Alice; Shaheen, Magda; Glenn, Beth A.; Bastani, Roshan

2010-01-01

Objectives: To assess the effect of a multicomponent intervention on parental knowledge, sun avoidance behaviors, and sun protection practices in children 3-10 years. Methods: A randomized trial at a pediatric clinic recruited 197 caregiver-child pairs (90% parents). Intervention included a brief presentation and brochure for the parent and…

Little sun

DEFF Research Database (Denmark)

Ebbesen, Toke Riis

2017-01-01

the ideas of Alfred Gell’s anthropology of art and the indicative framework derived from Argentinian semiotician Juan Pablo Bonta and Jørn Guldberg. The toy-like solar lamp Little Sun by Olafur Eliasson and Frederik Ottesen is used as case that blends the registers of social design and art......, and as an example of how designers attempt to determine meaning potentials through design in a complex interplay of different strategies. In the final analysis, what characterise objects like Little Sun is seldom that they communicate their meanings in themselves, but instead rely on forceful mediations to gain...

77 FR 34122 - Application of Sun Air Express, LLC, d/b/a Sun Air International for Commuter Authority

Science.gov (United States)

2012-06-08

... DEPARTMENT OF TRANSPORTATION Office of the Secretary [Docket DOT-OST-2011-0169] Application of Sun Air Express, LLC, d/b/a Sun Air International for Commuter Authority AGENCY: Department of... order finding Sun Air Express, LLC d/b/a Sun Air International fit, willing, and able, and awarding it...

The Sun and Earth

Science.gov (United States)

Gopalswamy, Natchimuthuk

2012-01-01

Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

Sun-Earth Day, 2001

Science.gov (United States)

Adams, Mitzi L.; Mortfield, P.; Hathaway, D. H.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

To promote awareness of the Sun-Earth connection, NASA's Marshall Space Flight Center, in collaboration with the Stanford SOLAR Center, sponsored a one-day Sun-Earth Day event on April 27, 2001. Although "celebrated" on only one day, teachers and students from across the nation, prepared for over a month in advance. Workshops were held in March to train teachers. Students performed experiments, results of which were shared through video clips and an internet web cast. Our poster includes highlights from student experiments (grades 2 - 12), lessons learned from the teacher workshops and the event itself, and plans for Sun-Earth Day 2002.

Sun burn incidence and knowledge of greek elementary and high school children about sun protection.

Science.gov (United States)

Saridi, Maria Ioannis; Toska, Aikaterini George; Rekleiti, Maria Dimitrios; Tsironi, Maria; Geitona, Maria; Souliotis, Kyriakos

2015-01-01

Overexposure to sun radiation and particularly its accumulation during childhood and adolescence is a significant risk factor for skin cancer development. The sun burn is particularly important. To estimate sun burn incidence in young pupils in a coastal area of Greece. Two surveys were conducted in a school population in the same district in Greece, over different periods of time, in young people 9 to 18 years old (n=2 977). Anonymous questionnaires were completed. Levels of significance were two- tailed and statistical significance was set at p=0.05. SPSS 17.0 software was used for statistical analysis. From the individual characteristics of the participants it was shown that the majority of them had dark hair and fair skin, whereas a significant percentage reported the existence of moles on face and their body (83.4% vs 68.1%). The sun burn incidence was high in adolescents and the younger pupils (41.9% vs 55.6%). The younger aged children who were living in an urban area had significantly higher rates of sun burn than those living in semi-urban areas (33.8% vs 24.8%, p=0.020). As far as the knowledge of pupils about the risks of sun radiation it was shown that the elementary school pupils had better knowledge than those at high school. Finally, those with better knowledge had the fewer sun burns (Mean 2.83 SD 0.87, pknowledge to the decrease of sun burn incidence is important as long as this is continuous. Therefore, the education should concern not only children but also teachers and parents in the context of continuous and systematic programs of health education.

Sun, Earth and Sky

CERN Document Server

Lang, Kenneth R

2006-01-01

This Second Edition of Sun, Earth and Sky updates the popular text by providing comprehensive accounts of the most recent discoveries made by five modern solar spacecraft during the past decade. Their instruments have used sound waves to peer deep into the Sun’s inner regions and measure the temperature of its central nuclear reactor, and extended our gaze far from the visible Sun to record energetic outbursts that threaten Earth. Breakthrough observations with the underground Sudbury Neutrino Observatory are also included, which explain the new physics of ghostly neutrinos and solve the problematic mismatch between the predicted and observed amounts of solar neutrinos. This new edition of Sun, Earth and Sky also describes our recent understanding of how the Sun’s outer atmosphere is heated to a million degrees, and just where the Sun’s continuous winds come from. As humans we are more intimately linked with our life-sustaining Sun than with any other astronomical object, and the new edition therefore p...

Wind, photovoltaic and fuel cell energy for communication stations; Energia eolica, fotovoltaica e de celula a combustivel para estacoes de comunicacao

Energy Technology Data Exchange (ETDEWEB)

Sousa, Iolanda; Pereira, Jose; Alcobia, Hernani [Net Plan Telecomunicacoes e Energia, Lisboa (Portugal); Pereirinha, Paulo [Instituto Politecnico de Coimbra (Portugal); Instituto para Engenharia de Sistemas e Computadores de Coimbra (Portugal)

2011-10-15

This paper presents a hybrid system that provides power to a remote and autonomously telecommunications station by means of electrical solar generators, wind and hydrogen fuel cell. In the absence of sufficient sun and wind, a bank of batteries and hydrogen produced on-site guarantee the power supply. The station can still be remote monitored and managed.

Cheap two axis sun following device

International Nuclear Information System (INIS)

Roth, P.; Georgiev, A.; Boudinov, H.

2005-01-01

A sun following system was constructed and tested. The tracker gives the possibility for automatic measuring of direct solar radiation with a phetylureum. The mechanism is operated by a digital program in the control system, situated separately from the mechanical part. The position of the sun is calculated, and the pointing errors appearing during its daily work are stored for later analysis. Additionally, in the active operation mode, the tracker uses the signal of a sun detecting linear sensor to control the pointing. Two stepper motors move the instrument platform, keeping the sun's beam at the center of the sensor. The mechanism was created at the Laboratory 'Evaluation Solar' of the Technical University Faradaic Santa Maria (UTFSM) in Valparaiso, Chile. The experiments show good results. The described sun tracker gives similar results as the Swiss sun tracker INTRA at a very much lower price

Clustering of Sun Exposure Measurements

OpenAIRE

Have, Anna Szynkowiak; Larsen, Jan; Hansen, Lars Kai; Philipsen, Peter Alshede; Thieden, Elisabeth; Wulf, Hans Christian

2002-01-01

In a medically motivated Sun-exposure study, questionnaires concerning Sun-habits were collected from a number of subjects together with UV radiation measurements. This paper focuses on identifying clusters in the heterogeneous set of data for the purpose of understanding possible relations between Sun-habits exposure and eventually assessing the risk of skin cancer. A general probabilistic framework originally developed for text and Web mining is demonstrated to be useful for clustering of b...

Climatological background for the utilization of energy from the sun

International Nuclear Information System (INIS)

Alterio, S.; Barabaro, S.; Coppolino, S.

1983-01-01

Information on the main climatological factors characterizing a given place or area is fundamental for the utilization of energy from the Sun and for other applications. This paper collects and analyses the daily, monthly and yearly average climatic data (insolation, sunshine, state of the sky, air temperature and relative humidity) provided by sixty thermopluviometric stations variously distributed in the territory of Sicily. The analysis is here performed both with a purely applicative view and in order to point out the connection between climate and physical environment. It leads to a better knowledge of solar climate and constitutes the basis for equally interesting further developments in the various fields of applied climatology: geomorfology, agriculture, biology, ecology, bioclimatology, etc

SUN-RAH: a nucleoelectric BWR university simulator based in reduced order models

International Nuclear Information System (INIS)

Morales S, J.B.; Lopez R, A.; Sanchez B, A.; Sanchez S, R.; Hernandez S, A.

2003-01-01

The development of a simulator that allows to represent the dynamics of a nucleo electric central, with nuclear reactor of the BWR type, using reduced order models is presented. These models present the characteristics defined by the dominant poles of the system (1) and most of those premature operation transitories in a power station can be reproduced with considerable fidelity if the models are identified with data of plant or references of a code of better estimate like RAMONA, TRAC (2) or RELAP. The models of the simulator are developments or own simplifications starting from the physical laws and retaining the main terms. This work describes the objective of the project and the general specifications of the University student of Nucleo electric simulator with Boiling Water Reactor type (SUN-RAH) as well as the finished parts that fundamentally are the nuclear reactor, the one of steam supply (NSSS), the plant balance (BOP), the main controllers of the plant and the implemented graphic interfaces. The pendent goals as well as the future developments and applications of SUN-RAH are described. (Author)

NEW SUNS IN THE COSMOS?

Energy Technology Data Exchange (ETDEWEB)

De Freitas, D. B.; Leao, I. C.; Lopes, C. E. Ferreira; Paz-Chinchon, F.; Canto Martins, B. L.; Alves, S.; De Medeiros, J. R. [Departamento de Fisica, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil); Catelan, M. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, 782-0436 Macul, Santiago (Chile)

2013-08-20

The present work reports on the discovery of three stars that we have identified to be rotating Sun-like stars, based on rotational modulation signatures inferred from light curves from the CoRoT mission's Public Archives. In our analysis, we performed an initial selection based on the rotation period and position in the period-T{sub eff} diagram. This revealed that the stars CoRoT IDs 100746852, 102709980, and 105693572 provide potentially good matches to the Sun with a similar rotation period. To refine our analysis, we applied a novel procedure, taking into account the fluctuations of the features associated with photometric modulation at different time intervals and the fractality traces that are present in the light curves of the Sun and of these ''New Sun'' candidates alike. In this sense, we computed the so-called Hurst exponent for the referred stars, for a sample of 14 CoRoT stars with sub- and super-solar rotational periods, and for the Sun itself in its active and quiet phases. We found that the Hurst exponent can provide a strong discriminant of Sun-like behavior, going beyond what can be achieved with solely the rotation period itself. In particular, we find that CoRoT ID 105693572 is the star that most closely matches the solar rotation properties as far as the latter's imprints on light curve behavior are concerned. The stars CoRoT IDs 100746852 and 102709980 have significant smaller Hurst exponents than the Sun, notwithstanding their similarity in rotation periods.

A simulation model for reliability evaluation of Space Station power systems

Science.gov (United States)

Singh, C.; Patton, A. D.; Kumar, Mudit; Wagner, H.

1988-01-01

A detailed simulation model for the hybrid Space Station power system is presented which allows photovoltaic and solar dynamic power sources to be mixed in varying proportions. The model considers the dependence of reliability and storage characteristics during the sun and eclipse periods, and makes it possible to model the charging and discharging of the energy storage modules in a relatively accurate manner on a continuous basis.

Associations between authoritative parenting and the sun exposure and sun protective behaviours of adolescents and their friends.

Science.gov (United States)

Mewse, Avril J; Lea, Stephen E G; Ntala, Eleni; Eiser, J Richard

2011-05-01

Associations between the sun exposure and sun protective behaviours of adolescents and their friends were examined along with the role played by authoritative parenting and other family and peer socialisation factors. Four hundred and two adolescents (198 males, 204 females) participated in the research. It was found that these adolescents and their friends shared similar sun exposure and sun protective behaviours and had similar parenting backgrounds. Parental authoritativeness was positively associated with the use of sun protection, even after the effects of other familial and peer variables were controlled, but not with the time spent sunbathing which was associated with friends' behaviours. The theoretical and practical implications of these findings are discussed.

SunShot solar power reduces costs and uncertainty in future low-carbon electricity systems.

Science.gov (United States)

Mileva, Ana; Nelson, James H; Johnston, Josiah; Kammen, Daniel M

2013-08-20

The United States Department of Energy's SunShot Initiative has set cost-reduction targets of $1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to $20 billion ($2010) annually by 2050 relative to scenarios with Reference solar costs.

Integrable multi parametric SU(N) chain

International Nuclear Information System (INIS)

Foerster, Angela; Roditi, Itzhak; Rodrigues, Ligia M.C.S.

1996-03-01

We analyse integrable models associated to a multi parametric SU(N) R-matrix. We show that the Hamiltonians describe SU(N) chains with twisted boundary conditions and that the underlying algebraic structure is the multi parametric deformation of SU(N) enlarged by the introduction of a central element. (author). 15 refs

System control and data acquisition of the two new FWCD RF systems at DIII-D

International Nuclear Information System (INIS)

Harris, T.E.; Allen, J.C.; Cary, W.P. Petty, C.C.

1995-10-01

The Fast Wave Current Drive (FWCD) system at DIII-D has increased its available radio frequency (RF) power capabilities with the addition of two new high power transmitters along with their associated transmission line systems. A Sun Sparc-10 workstation, functioning as the FWCD operator console, is being used to control transmitter operating parameters and transmission line tuning parameters, along with acquiring data and making data available for integration into the DIII-D data acquisition system. Labview, a graphical user interface application, is used to manage and control the above processes. This paper will discuss the three primary branches of the FWCD computer control system: transmitter control, transmission line tuning control, and FWCD data acquisition. The main control program developed uses VXI, GPIB, CAMAC, Serial, and Ethernet protocols to blend the three branches together into one cohesive system. The control of the transmitters utilizes VXI technology to communicate with the transmitter's digital interface. A GPIB network allows for communication with various instruments and CAMAC crate controllers. CAMAC crates are located at each phase-shifter/stub-tuner station and are used to digitize transmission line parameters along with transmission line fault detection during RF transmission. The phase-shifter/stub-tuner stations are located through out the DIII-D facility and are controlled from the FWCD operator console via the workstation's Serial port. The Sun workstation has an Ethernet connection allowing for the utilization of the DIII-D data acquisition open-quotes Open Systemclose quotes architecture and of course providing communication with the rest of the world

Trends in sunburns, sun protection practices, and attitudes toward sun exposure protection and tanning among US adolescents, 1998-2004.

Science.gov (United States)

Cokkinides, Vilma; Weinstock, Martin; Glanz, Karen; Albano, Jessica; Ward, Elizabeth; Thun, Michael

2006-09-01

Sun exposure in childhood is an important risk factor for developing skin cancer as an adult. Despite extensive efforts to reduce sun exposure among the young, there are no population-based data on trends in sunburns and sun protection practices in the young. The aim of this study was to describe nationally representative trend data on sunburns, sun protection, and attitudes related to sun exposure among US youth. Cross-sectional telephone surveys of youth aged 11 to 18 years in 1998 (N = 1196) and in 2004 (N = 1613) were conducted using a 2-stage sampling process to draw population-based samples. The surveys asked identical questions about sun protection, number of sunburns experienced, and attitudes toward sun exposure. Time trends were evaluated using pooled logistic regression analysis. In 2004, 69% of subjects reported having been sunburned during the summer, not significantly less than in 1998 (72%). There was a significant decrease in the percentage of those aged 11 to 15 years who reported sunburns and a nonsignificant increase among the 16- to 18-year-olds. The proportion of youth who reported regular sunscreen use increased significantly from 31% to 39%. Little change occurred in other recommended sun protection practices. A small reduction in sunburn frequency and modest increases in sun protection practices were observed among youth between 1998 and 2004, despite widespread sun protection campaigns. Nevertheless, the decrease in sunburns among younger teens may be cause for optimism regarding future trends. Overall, there was rather limited progress in improving sun protection practices and reducing sunburns among US youth between 1998 and 2004.

After the Bell: Developing Sun Sense--Learning about Protection from the Sun's Rays

Science.gov (United States)

Farenga, Stephen J.; Ness, Daniel

2008-01-01

The American Academy of Dermatology (2008) reports that our students will experience 80% of their lifetime exposure to the Sun by the time they are 18. Further, research has demonstrated that continued exposure to the Sun's ultraviolet rays can lead to skin aging, sunburn, immune suppression, ocular melanoma, cataracts, corneal burns, and even…

Vibration Based Sun Gear Damage Detection

Science.gov (United States)

Hood, Adrian; LaBerge, Kelsen; Lewicki, David; Pines, Darryll

2013-01-01

Seeded fault experiments were conducted on the planetary stage of an OH-58C helicopter transmission. Two vibration based methods are discussed that isolate the dynamics of the sun gear from that of the planet gears, bearings, input spiral bevel stage, and other components in and around the gearbox. Three damaged sun gears: two spalled and one cracked, serve as the focus of this current work. A non-sequential vibration separation algorithm was developed and the resulting signals analyzed. The second method uses only the time synchronously averaged data but takes advantage of the signal/source mapping required for vibration separation. Both algorithms were successful in identifying the spall damage. Sun gear damage was confirmed by the presence of sun mesh groups. The sun tooth crack condition was inconclusive.

As reliable as the sun

Science.gov (United States)

Leijtens, J. A. P.

2017-11-01

Fortunately there is almost nothing as reliable as the sun which can consequently be utilized as a very reliable source of spacecraft power. In order to harvest this power, the solar panels have to be pointed towards the sun as accurately and reliably as possible. To this extend, sunsensors are available on almost every satellite to support vital sun-pointing capability throughout the mission, even in the deployment and save mode phases of the satellites life. Given the criticality of the application one would expect that after more than 50 years of sun sensor utilisation, such sensors would be fully matured and optimised. In actual fact though, the majority of sunsensors employed are still coarse sunsensors which have a proven extreme reliability but present major issues regarding albedo sensitivity and pointing accuracy.

How to Observe the Sun Safely

CERN Document Server

Macdonald, Lee

2012-01-01

How to Observe the Sun Safely, Second Edition gives all the basic information and advice the amateur astronomer needs to get started in observing our own ever-fascinating star. Unlike many other astronomical objects, you do not need a large telescope or expensive equipment to observe the Sun. And it is possible to take excellent pictures of the Sun with today's low-cost digital cameras! This book surveys what is visible on the Sun and then describes how to record solar features and measure solar activity levels. There is also an account of how to use H-alpha and Calcium-K filters to observe and record prominences and other features of the solar chromosphere, the Sun's inner atmosphere. Because we are just entering a period of high activity on the Sun, following a long, quiet period, this is a great time to get involved with solar observing. Still emphasizing safety first, this Second Edition reflects recent and exciting advances in solar observing equipment. Chapters 6 through 8 have been completely revised ...

The Hetu'u Global Network: Measuring the Distance to the Sun with the Transit of Venus

Science.gov (United States)

Rodriguez, David; Faherty, J.

2013-01-01

In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the 2012 transit of Venus. In total, our group (stationed at Easter Island, Chile) recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu’u Global Network. Applying the methods of French astronomer Joseph-Nicolas Delisle, we used individual second and third Venus-Sun contact times to calculate the distance to the Sun. Ten of the sites in our network had amiable weather; 8 of which measured second contact and 5 of which measured third contact leading to consistent solar distance measurements of 152+/-30 million km and 163+/-30 million km respectively. The distance to the Sun at the time of the transit was 152.25 million km; therefore, our measurements are also consistent within 1-sigma of the known value. The goal of our international school group network was to inspire the next generation of scientists using the excitement and accessibility of such a rare astronomical event. In the process, we connected hundreds of participating students representing a diverse, multi-cultural group with differing political, economic, and racial backgrounds.

Clustering of Sun Exposure Measurements

DEFF Research Database (Denmark)

Have, Anna Szynkowiak; Larsen, Jan; Hansen, Lars Kai

2002-01-01

In a medically motivated Sun-exposure study, questionnaires concerning Sun-habits were collected from a number of subjects together with UV radiation measurements. This paper focuses on identifying clusters in the heterogeneous set of data for the purpose of understanding possible relations between...... Sun-habits exposure and eventually assessing the risk of skin cancer. A general probabilistic framework originally developed for text and Web mining is demonstrated to be useful for clustering of behavioral data. The framework combines principal component subspace projection with probabilistic...

'My child did not like using sun protection': practices and perceptions of child sun protection among rural black African mothers.

Science.gov (United States)

Kunene, Zamantimande; Albers, Patricia N; Lucas, Robyn M; Banwell, Cathy; Mathee, Angela; Wright, Caradee Y

2017-08-25

Photodamage is partially mitigated by darker skin pigmentation, but immune suppression, photoaging and cataracts occur among individuals with all skin types. To assess practices and acceptability to Black African mothers of sun protection equipment for their children living in a rural area, participants were recruited at the time of their child's 18-month vaccinations. Mothers completed a baseline questionnaire on usual sun behaviours and sun protection practices. They were then provided with sun protection equipment and advice. A follow-up questionnaire was administered two weeks later. Mothers reported that during the week prior to the baseline questionnaire, children spent on average less than 1 hour of time outdoors (most often spent in the shade). Most mothers (97%) liked the sun protection equipment. However, many (78 of 86) reported that their child did not like any of the sun protection equipment and two-thirds stated that the sun protection equipment was not easy to use. Among Black Africans in rural northern South Africa, we found a mismatch between parental preferences and child acceptance for using sun protection when outdoors. A better understanding of the health risks of incidental excess sun exposure and potential benefits of sun protection is required among Black Africans.

A study on variation in position of an Indian station due to solid earth ...

Indian Academy of Sciences (India)

position of a station and its subsequent influence on the computation and interpretation of time series of coordinates ... signals (such as ocean tide loading and errors in .... moon or full moon. Neap tide is that when the Sun,. Earth, and Moon are aligned in perpendicular line, due to which they form destructive interface and.

Sounds of space: listening to the Sun-Earth connection

Science.gov (United States)

Craig, N.; Mendez, B.; Luhmann, J.; Sircar, I.

2003-04-01

NASA's STEREO/IMPACT Mission includes an Education and Public Outreach component that seeks to offer national programs for broad audiences highlighting the mission's solar and geo-space research. In an effort to make observations of the Sun more accessible and exciting for a general audience, we look for alternative ways to represent the data. Scientists most often represent data visually in images, graphs, and movies. However, any data can also be represented as sound audible to the human ear, a process known as sonification. We will present our plans for an exciting prototype program that converts the science results of solar energetic particle data to sound. We plan to make sounds, imagery, and data available to the public through the World Wide Web where they may create their own sonifications, as well as integrate this effort to a science museum kiosk format. The kiosk station would include information on the STEREO mission and monitors showing images of the Sun from each of STEREO's two satellites. Our goal is to incorporate 3D goggles and a headset into the kiosk, allowing visitors to see the current or archived images in 3D and hear stereo sounds resulting from sonification of the corresponding data. Ultimately, we hope to collaborate with composers and create musical works inspired by these sounds and related solar images.

Caddo Sun Accounts across Time and Place

Science.gov (United States)

Gerona, Carla

2012-01-01

Billy Day, a Tunica/Biloxi, recently described the significance of the sun for Caddoan people. Day quoted an "old Caddo relative" of his who said: "I used to go outside and hold my hands up and bless myself with the sun--'a'hat.' Well, I can't do that anymore because they say we are sun worshipers. We didn't worship the sun. We worshiped what was…

SunPy—Python for solar physics

International Nuclear Information System (INIS)

Community, The SunPy; Mumford, Stuart J; Freij, Nabil; Bennett, Samuel M; Christe, Steven; Ireland, Jack; Shih, Albert Y; Inglis, Andrew R; Pérez-Suárez, David; Liedtke, Simon; Hewett, Russell J; Mayer, Florian; Hughitt, Keith; Meszaros, Tomas; Malocha, Michael; Evans, John; Agrawal, Ankit; Leonard, Andrew J; Robitaille, Thomas P; Mampaey, Benjamin

2015-01-01

This paper presents SunPy (version 0.5), a community-developed Python package for solar physics. Python, a free, cross-platform, general-purpose, high-level programming language, has seen widespread adoption among the scientific community, resulting in the availability of a large number of software packages, from numerical computation (NumPy, SciPy) and machine learning (scikit-learn) to visualization and plotting (matplotlib). SunPy is a data-analysis environment specializing in providing the software necessary to analyse solar and heliospheric data in Python. SunPy is open-source software (BSD licence) and has an open and transparent development workflow that anyone can contribute to. SunPy provides access to solar data through integration with the Virtual Solar Observatory (VSO), the Heliophysics Event Knowledgebase (HEK), and the HELiophysics Integrated Observatory (HELIO) webservices. It currently supports image data from major solar missions (e.g., SDO, SOHO, STEREO, and IRIS), time-series data from missions such as GOES, SDO/EVE, and PROBA2/LYRA, and radio spectra from e-Callisto and STEREO/SWAVES. We describe SunPy's functionality, provide examples of solar data analysis in SunPy, and show how Python-based solar data-analysis can leverage the many existing tools already available in Python. We discuss the future goals of the project and encourage interested users to become involved in the planning and development of SunPy. (paper)

Mediation analysis of decisional balance, sun avoidance and sunscreen use in the precontemplation and preparation stages for sun protection.

Science.gov (United States)

Santiago-Rivas, Marimer; Velicer, Wayne F; Redding, Colleen

2015-01-01

Mediation analyses of sun protection were conducted testing structural equation models using longitudinal data with three waves. An effect was said to be mediated if the standardised path between processes of change, decisional balance and sun protection outcomes was significant. Longitudinal models of sun protection using data from individuals in the precontemplation (N = 964) and preparation (N = 463) stages who participated of an expert system intervention. Nine processes of change for sun protection, decisional balance constructs of sun protection (pros and cons), sun avoidance behaviour and sunscreen use. With the exception of two processes in the preparation stage, processes of change predicted the pros (r = .126-.614), and the pros predicted the outcomes (r = .181-.272). Three models with the cons as mediator in the preparation stage, and none in the precontemplation stage, showed a mediated relationship between processes and outcomes. In general, mediation analyses found both the process of change-to-pros and pros-to-behaviour paths significant for both precontemplation and preparation stages, and for both sun avoidance and sunscreen use outcomes. Findings provide support for the importance of assessing the role of underlying risk cognitions in improving sun protection adherence.

The Sun in Time

Science.gov (United States)

Adams, Mitzi L.; Bero, Elizabeth; Sever, Thomas L.

1999-01-01

Leveraging funds from NASA's Initiative to Develop Education through Astronomy and Space Science (IDEAS) program, we combined the expertise of an archaeoastronomer, a solar scientist, and a teacher to trace humankind's view of the Sun and how that has changed, from the time of Stonehenge in about 1800 B.C.E., to the time of the Maya in 700 C.E., up to the modem era. Our program was aimed at middle-school students in an attempt to explain not only how science is done today, but how science has evolved from the observations of ancient societies. From these varied cultures, we touched on methods of observing the Sun, ideas of the composition of the Sun, and the relationship of the Sun to everyday life. Further, using the von Braun Astronomical Society's Planetarium in Huntsville, Alabama as a test-bed for the program, we illustrated concepts such as solstices, equinoxes, and local noon with approximately 800 eighth grade students from the local area. Our presentation to SEPA will include a description of NASA's IDEAS program and how to go about partnering with a NASA astronomer, some slides from our planetarium program and web-site, and some hands-on activities.

Sun-care product advertising in parenting magazines: what information does it provide about sun protection?

Science.gov (United States)

Kang, Hannah; Walsh-Childers, Kim

2014-01-01

This study analyzed the content of sun-care product advertisements in five major U.S. parenting magazines with high circulation: Family Circle, Parents, Family Fun, Parenting (Early Years), and Parenting (School Years). The study examined what information sun-care product advertisements tell parents about skin cancer prevention and about sunscreen use for themselves or for their children based on the Health Belief Model concepts of perceived benefits and perceived barriers. Results showed that the most commonly mentioned benefit of the product was that it blocks ultraviolet A (UVA) and ultraviolet B (UVB) rays. One-third of the ads promoted the product's effectiveness in overcoming four of the barriers that prevent people from using sunscreens: eye irritation, skin irritation, an unpleasant smell, and the need to reapply sunscreen too often or after physical activity. However, only a few of the ads provided information about the consequences of unprotected sun exposure or mentioned methods of sun protection or skin cancer prevention other than sunscreen use. We discuss the implications of these messages for parents' ability to understand correctly how to protect their children from damaging sun exposure.

The Sun on Trial

Science.gov (United States)

Robitaille, Pierre-Marie

2014-03-01

For 150 years, the Sun has been seen as a gaseous object devoid of a surface, as required by the Standard Solar Model (SSM). Yet, not one line of observational evidence supports a gaseous Sun. In contrast, overwhelming evidence exists that the Sun is comprised of condensed matter. Recently, 40 proofs have been compiled in conjunction with the Liquid Metallic Hydrogen Solar Model (LMHSM). This model advances that the Sun has a true surface. Photospheric structures, such as sunspots, granules, and faculae, are not optical illusions, as in the SSM, but real objects with a condensed nature. The LMHSM accounts for the thermal spectrum by invoking true inter-atomic structure on the photosphere in the form of the graphite-like layered hexagonal metallic hydrogen lattice first proposed by Wigner and Huntington. Within the convection zone, layered metallic hydrogen, insulated by intercalate atoms, enables the generation of the solar dynamo. Electrons located in conduction bands provide a proper means of generating magnetic fields. Metallic hydrogen ejected from the photosphere also thinly populates the corona, as reflected by the continuous K-coronal spectrum. This coronal matter harvests electrons, resulting in the production of highly ionized atoms. Electron affinity, not temperature, governs the ion profile. The chromosphere is a site of hydrogen and proton capture. Line emission in this region, strongly supports the idea that exothermic condensation reactions are occurring in the chromosphere. In the LMHSM, solar activity and solar winds are regulated by exfoliation reactions occurring in the Sun itself, as the metallic hydrogen lattice excludes non-hydrogen elements from the solar body.

Sun Protection for Children: A Review

Directory of Open Access Journals (Sweden)

Nazanin Shafie Pour

2015-01-01

Full Text Available Chronic ultraviolet exposure results in premature skin aging (photoaging, dyspigmentation, sallow color, textural changes, loss of elasticity, and premalignant actinic keratoses. UVB radiation is mainly responsible for acute damages such as sunburn, and long-term damage including melanoma. Today the sun's ultraviolet radiation (UVR induced skin cancer is a major issue worldwide. History of sun exposure and sunburns are the most important behavioral risks. Childhood sun exposure is considered as a substantial risk because a child’s skin has a thinner stratum corneum, lower levels of protective melanin, and a higher surface area to body-mass-ratio. Thus, protection against UVR in childhood is essential. Research has shown that people who have had a sunburn in childhood or were in the sun unprotected are more likely to have skin cancer. In this article, we review the literature to address the protection of children against sun and skin cancer.

The Sun and How to Observe It

CERN Document Server

Jenkins, Jamey L

2009-01-01

Without the Sun, all life on Earth would perish. But what exactly do we know about this star that lights, heats, and powers Earth? Actually, we know quite a lot, thanks mainly to a host of eager solar observers. Looking directly at the Sun is EXTREMELY hazardous. But many astronomers, both professional and amateur, have found ways to view the Sun safely to learn about it. You, too, can view the Sun in all of its glorious detail. Some of the newest, most exciting telescopes on the market are affordable to amateur astronomers or even just curious sky watchers, and with this guide to what the Sun has to offer, including sunspots, prominences, and flares, plus reviews of the latest instruments for seeing and capturing images of the Sun, you can contribute to humankind’s knowledge of this immense ball of glowing gases that gives us all life. For a complete guide to Sun viewing, see also Total Solar Eclipses and How to Observe Them (2007) by Martin Mobberley in this same series.

Does the sun ring

International Nuclear Information System (INIS)

Isaak, G.R.

1978-01-01

The work of various groups, which have been investigating the possibility of measuring the periodicities of solar oscillations in an attempt to test theoretical models of the sun, is reported. In particular the observation of small velocity oscillations of the surface layers of the sun that permits the measurement of the sound waves (or phonons) in the solar atmosphere, is discussed. Oscillations with periods of 2.65 h, 58 and 40 min and amplitudes of 2.7, 0.8 and 0.7 ms -1 respectively are reported. Support for a periodicity at about 2.65 h from a number of other groups using other measuring techniques are considered. It is felt that the most probable interpretation of the observed solar oscillations is that the sun is a resonator which is ringing. (UK)

Mission Analysis for LEO Microwave Power-Beaming Station in Orbital Launch of Microwave Lightcraft

Science.gov (United States)

Myrabo, L. N.; Dickenson, T.

2005-01-01

A detailed mission analysis study has been performed for a 1 km diameter, rechargeable satellite solar power station (SPS) designed to boost 20m diameter, 2400 kg Micr,oWave Lightcraft (MWLC) into low earth orbit (LEO) Positioned in a 476 km daily-repeating oi.bit, the 35 GHz microwave power station is configured like a spinning, thin-film bicycle wheel covered by 30% efficient sola cells on one side and billions of solid state microwave transmitter elements on the other, At the rim of this wheel are two superconducting magnets that can stor,e 2000 G.J of energy from the 320 MW, solar array over a period of several orbits. In preparation for launch, the entire station rotates to coarsely point at the Lightcraft, and then phases up using fine-pointing information sent from a beacon on-board the Lightcraft. Upon demand, the station transmits a 10 gigawatt microwave beam to lift the MWLC from the earth surface into LEO in a flight of several minutes duration. The mission analysis study was comprised of two parts: a) Power station assessment; and b) Analysis of MWLC dynamics during the ascent to orbit including the power-beaming relationships. The power station portion addressed eight critical issues: 1) Drag force vs. station orbital altitude; 2) Solar pressure force on the station; 3) Station orbital lifetime; 4) Feasibility of geo-magnetic re-boost; 5) Beta angle (i..e., sola1 alignment) and power station effective area relationship; 6) Power station percent time in sun vs, mission elapsed time; 7) Station beta angle vs.. charge time; 8) Stresses in station structures.. The launch dynamics portion examined four issues: 1) Ascent mission/trajecto1y profile; 2) MWLC/power-station mission geometry; 3) MWLC thrust angle vs. time; 4) Power station pitch rate during power beaming. Results indicate that approximately 0 58 N of drag force acts upon the station when rotated edge-on to project the minimum frontal area of 5000 sq m. An ion engine or perhaps an electrodynamic

‘My child did not like using sun protection’: practices and perceptions of child sun protection among rural black African mothers

Directory of Open Access Journals (Sweden)

Zamantimande Kunene

2017-08-01

Full Text Available Abstract Background Photodamage is partially mitigated by darker skin pigmentation, but immune suppression, photoaging and cataracts occur among individuals with all skin types. Methods To assess practices and acceptability to Black African mothers of sun protection equipment for their children living in a rural area, participants were recruited at the time of their child’s 18-month vaccinations. Mothers completed a baseline questionnaire on usual sun behaviours and sun protection practices. They were then provided with sun protection equipment and advice. A follow-up questionnaire was administered two weeks later. Results Mothers reported that during the week prior to the baseline questionnaire, children spent on average less than 1 hour of time outdoors (most often spent in the shade. Most mothers (97% liked the sun protection equipment. However, many (78 of 86 reported that their child did not like any of the sun protection equipment and two-thirds stated that the sun protection equipment was not easy to use. Conclusions Among Black Africans in rural northern South Africa, we found a mismatch between parental preferences and child acceptance for using sun protection when outdoors. A better understanding of the health risks of incidental excess sun exposure and potential benefits of sun protection is required among Black Africans.

Sun meter

Science.gov (United States)

Younskevicius, Robert E.

1978-01-01

A simple, inexpensive device for measuring the radiation energy of the sun impinging on the device. The measurement of the energy over an extended period of time is accomplished without moving parts or tracking mechanisms.

Sun Safe Mode Controller Design for LADEE

Science.gov (United States)

Fusco, Jesse C.; Swei, Sean S. M.; Nakamura, Robert H.

2015-01-01

This paper presents the development of sun safe controllers which are designed to keep the spacecraft power positive and thermally balanced in the event an anomaly is detected. Employed by NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE), the controllers utilize the measured sun vector and the spacecraft body rates for feedback control. To improve the accuracy of sun vector estimation, the least square minimization approach is applied to process the sensor data, which is proven to be effective and accurate. To validate the controllers, the LADEE spacecraft model engaging the sun safe mode was first simulated and then compared with the actual LADEE orbital fight data. The results demonstrated the applicability of the proposed sun safe controllers.

Sun tracker for clear or cloudy weather

Science.gov (United States)

Scott, D. R.; White, P. R.

1979-01-01

Sun tracker orients solar collector so that they absorb maximum possible sunlight without being fooled by bright clouds, holes in cloud cover, or other atmospheric conditions. Tracker follows sun within 0.25 deg arc and is accurate within + or - 5 deg when sun is hidden.

Prototype of sun projector device

Science.gov (United States)

Ihsan; Dermawan, B.

2016-11-01

One way to introduce astronomy to public, including students, can be handled by solar observation. The widely held device for this purpose is coelostat and heliostat. Besides using filter attached to a device such as telescope, it is safest to use indirect way for observing the Sun. The main principle of the indirect way is deflecting the sun light and projecting image of the sun on a screen. We design and build a simple and low-cost astronomical device, serving as a supplement to increase public service, especially for solar observation. Without using any digital and intricate supporting equipment, people can watch and relish image of the Sun in comfortable condition, i.e. in a sheltered or shady place. Here we describe a design and features of our prototype of the device, which still, of course, has some limitations. In the future, this prototype can be improved for more efficient and useful applications.

The Award Winning Black Suns

Science.gov (United States)

Holbrook, Jarita

2018-01-01

Black Suns: An Astrophysics Adventure is a documentary film focusing on the annular and total solar eclipses of 2012. We made a different kind of astronomy documentary showing the human aspects rather than just focusing on pretty astronomy pictures. The film combines personal stories with science. Our heroes are Hakeem Oluseyi and Alphonse Sterling, who valiantly travel to study the solar corona during total solar eclipses. The goals of the film included presenting three dimensional scientists, to show their paths to becoming astrophysicists, and to show them as they collect data and work as scientists. Drama and tension surround taking data during the small window of time during totality. The Black Suns was filmed in Tokyo, Cairns, Tucson, and Melbourne Florida. Uniquely, the film began through a Kickstarter campaign to fund travel and filming in Tokyo. Many American Astronomical Society members donated to the film! Black Suns won the Jury Prize at the 2017 Art of Brooklyn Film Festival. Black Suns will be screening in full on ???.

Sun-Earth Day Connects History, Culture and Science

Science.gov (United States)

Cline, T.; Thieman, J.

2003-12-01

The NASA Sun-Earth Connection Education forum annually promotes and event called Sun-Earth Day: a national celebration of the Sun, the space around the Earth (geospace), and how all of it affects life on our planet. For the past 3 years this event has provided a venue by which classrooms, museums, planetaria, and at NASA centers have had a sensational time sharing stories, images, and activities related to the Sun-Earth connections and the views o fthe Sun from Earth. Each year we select a different theme by which NASA Space Science can be further related to cross-curricular activities. Sun-Earth Day 2002, "Celebrate the Equinox", drew parallels between Native American Cultures and NASA's Sun-Earth Connection research via cultural stories, interviews, web links, activities and Native American participation. Sun-Earth Day 2003, "Live From the Aurora", shared the beauty of the Aurora through a variety of activities and stories related to perspectives of Northern Peoples. Sun-Earth Day 2004 will share the excitement of the transit of Venus through comparisons of Venus with Earth and Mars, calculations of the distances to nearby stars, and the use of transits to identify extra-solar planets. Finally, Sun-Earth Day 2005 will bring several of these themes together by turning our focus to the history and culture surrounding ancient observatories such as Chaco Canyon, Machu Picchu, and Chichen Itza.

The shivering sun opens its heart

International Nuclear Information System (INIS)

Gough, D.

1976-01-01

Recent discoveries, by various workers, of global oscillations of the Sun are summarised. The two major ways in which the Sun can vibrate, as a standing acoustic wave and as a standing gravity wave, are discussed. The recently discovered oscillations provide a new rich class of data with which to test theoretical models of the internal structure of the Sun. The implications of these new data with reference to solar models are considered. (U.K.)

Tribute to Sun Kwok

International Nuclear Information System (INIS)

Leung, Kam Ching

2016-01-01

Sun Kwok was bom in Hong Kong in 1949. He did all his early schooling in Hong Kong and went to the same high school, Pui Ching Middle School, as I did but he was more than a decade later. There are two Education Systems in Hong Kong; the Chinese Language Schools and English Language School. Pui Ching was started by Christian missionaries in China and has a long history of providing quality education. Pui Ching is a Chinese Language School, and during colonial times, school entrance was difficult for students as we were not eligible to apply for admission to the University of Hong Kong, nor were we able to join the civil service. In spite of these handicaps, the school still managed to produce many excellent academics, including one Nobel Prize winner in physics and one Field's medalist in mathematics. Most of its graduates who sought further education went to the U.S. Or Canada as Sun Kwok did. Sun graduated from McMaster University and then went to the University of Minnesota for graduate studies. In the early 1970s, the University of Minnesota had just built one of the world's first infrared bolometers and the astronomers there (Nick Woolf and Ed Ney) were able to make some of the first infrared observations in the mid-infrared region. Through these observations, circumstellar dust was discovered, leading to the realization the evolved stars are losing mass. Sun wrote his PhD thesis on the mass loss mechanism of red giant stars, proposing that the stellar winds are driven by the mechanism of radiation pressure on grains. His 1975 paper is still widely cited to this date. In the same thesis, he showed that OH maser emission is a manifestation of the mass loss process and OH/IR stars are the most heavily mass-losing stars known. He went back to Canada for postdoctoral studies, first at UBC and then at York University. While at York, he applied his knowledge of mass loss to the problem of formation of planetary nebulae, leading to now well-established interacting

Analysis of COMS-1 North-South Station Keeping Method

Directory of Open Access Journals (Sweden)

Hae-Yeon Kim

2005-12-01

Full Text Available The perturbations caused by the Sun and the Moon are predominantly out-of-plane effects causing a change in the inclination and in the right ascension of ascending node of a geostationary satellite. Due to the change of the inclination, subsatellite latitude of the geostationary satellite has a daily variations of the same magnitude of the inclination. Therefore we need a facility to control the orbital inclination and right ascension of ascending node for maintaining the satellite position in specified subsatellite latitude boundary using thrusters. In this paper we studied North-South station keeping strategies of the COMS-1 such as Track-Back Chord Target (TBCT method, Maximum Compensation Target (MCT method and Minimum Fuel Target (MFT method. We accomplished those North-South station keeping maneuvers for one year starting from December 2008. The required velocity increments to maintain the satellite are estimated as MCT 52.6065m/s, TBCT 52.2383m/s, MFT 51.5428m/s, respectively. We demonstrated that TBCT and MFT methods are proper to North-South station keeping for COMS-1. MFT method showed the minimum required velocity increments whereas TBCT traced narrow inclination boundary area for North-South station keeping.

Analysis of meiosis in SUN1 deficient mice reveals a distinct role of SUN2 in mammalian meiotic LINC complex formation and function.

Directory of Open Access Journals (Sweden)

Jana Link

2014-02-01

Full Text Available LINC complexes are evolutionarily conserved nuclear envelope bridges, composed of SUN (Sad-1/UNC-84 and KASH (Klarsicht/ANC-1/Syne/homology domain proteins. They are crucial for nuclear positioning and nuclear shape determination, and also mediate nuclear envelope (NE attachment of meiotic telomeres, essential for driving homolog synapsis and recombination. In mice, SUN1 and SUN2 are the only SUN domain proteins expressed during meiosis, sharing their localization with meiosis-specific KASH5. Recent studies have shown that loss of SUN1 severely interferes with meiotic processes. Absence of SUN1 provokes defective telomere attachment and causes infertility. Here, we report that meiotic telomere attachment is not entirely lost in mice deficient for SUN1, but numerous telomeres are still attached to the NE through SUN2/KASH5-LINC complexes. In Sun1(-/- meiocytes attached telomeres retained the capacity to form bouquet-like clusters. Furthermore, we could detect significant numbers of late meiotic recombination events in Sun1(-/- mice. Together, this indicates that even in the absence of SUN1 telomere attachment and their movement within the nuclear envelope per se can be functional.

Tanel Padar & The Sun veab õhukitarri

Index Scriptorium Estoniae

2008-01-01

Õhukitarri Eesti meistrivõistlustest 19. apr. Tallinnas Rock Cafés (võistluste eestvedajaks on ansambel Tanel Padar & The Sun, kes samas esitleb oma esimest ingliskeelset albumit "Here Comes The Sun")

Evaluation of knowledge, attitude, and behavior about harmful effects of the sun and sun protection among patients attending an outpatient clinic

Directory of Open Access Journals (Sweden)

Sevim Terzi

2017-03-01

Full Text Available Background and Design: The aim of the study was to evaluate harmful effects of sun exposure and knowledge, attitude and behaviors related to sun protection among patients attending our outpatient clinic. Materials and Methods: A total of 400 patients (171 male and 229 female aged between 16 and 89 years were included in this study. Subjects were requested to fill out a questionnaire composed of 52 questions. In the first part of the questionnaire, patients’ socio-demographic characteristics, history of sunburn, first-degree relatives with a history of skin cancer; in the second part, knowledge about harmful effects of sun and sun protection were inquired. In the third part, patient attitude and behaviors related to sun protection was evaluated. Results: Our results revealed that 69.25% of patients had satisfactory level of knowledge. While the level of knowledge was not affected by economic status, place of residence, skin type and presence of skin cancer in participants or their first-degree relatives, it was found to be increased with increasing educational level. The patients were found to prefer avoiding mid-day sun (75.5% and staying in the shade (64.8% chiefly as sun protection methods and 45.3% of patients were found to use sunscreens. Most frequently preferred sources of information about harmful effects of the sun and sun protection methods were found to be television, magazines and newspapers (76.3%, doctor’s advice and internet, respectively. Conclusion: Although a satisfactory level of knowledge about harmful effects of the sun and protection methods was found, it was observed that individuals could not convert their knowledge into the sun protection behavior

Sun behaviour after cutaneous malignant melanoma

DEFF Research Database (Denmark)

Idorn, L W; Datta, P; Heydenreich, J

2013-01-01

Background  It has been reported that patients with cutaneous malignant melanoma (CMM) can lower their risk of a second primary melanoma by limiting recreational sun exposure. Previous studies based on questionnaires and objective surrogate measurements indicate that before their diagnosis......, patients with CMM are exposed to higher ultraviolet radiation (UVR) doses than controls, followed by a reduction after diagnosis. Objectives  In a prospective, observational case-control study, we aimed to assess sun exposure after diagnosis of CMM by objective measurements to substantiate advice about sun...... months and 6 years before the start of the study. During a summer season participants filled in sun exposure diaries daily and wore personal electronic UVR dosimeters in a wristwatch that continuously measured time-stamped UVR doses in standard erythema dose. Results  The UVR dose of recently diagnosed...

Fly me to the Sun! ESA inaugurates the European Project on the Sun

Science.gov (United States)

2000-11-01

In an initiative mounted by ECSITE (European Collaborative for Science, Industry and Technology Exhibitions) with funding from the European Commission and under the supervision, coordination and co-sponsorship of ESA, five teams of youngsters (16-18 years old) from Belgium, France, Germany, Italy and the Netherlands were selected and coordinated by European science museums from each of their countries (Musée des Sciences et des Techniques - Parentville, B; Cité de l'Espace - Toulouse, F; Deutsches Museum - Munich, D; Fondazione IDIS - Naples, I; Foundation Noordwijk Space Expo - Noordwijk, NL). The teams each focused on a theme related to solar research: "How does the Sun work?" (I), "The Sun as a star" (F), "Solar activity" (NL), "Observing the Sun" (D), "Humans and the Sun" (B), and built exhibition "modules" that they will present at the inauguration, in the context of European Science and Technology Week 2000 (6-10 November), promoted by the European Commission. During the two-day event, a jury of representatives of other European science and technology museums, ESA scientists, a science journalist, and two ESA astronauts (Frank de Winne and Andre Kuipers) will judge the youngsters' exhibition modules on the basis of their scientific correctness, their museological value and the commitment shown by the young "communication experts". The winning team will be officially announced on 9 November. The prize is a weekend at the Space Camp in Redu, Belgium. The objective of the European Project on the Sun is educational. It aims, through the direct and "fresh" involvement of youngsters, to heighten European citizens' awareness of space research in general and the Sun's influence on our daily lives in particular. The role of the European Space Agency as reference point in Europe for solar research has been fundamental to the project. From ESA's perspective, EPOS is part of this autumn's wider communication initiative called the Solar Season, which is highlighting ESA

Influence of age, gender, educational level and self-estimation of skin type on sun exposure habits and readiness to increase sun protection.

Science.gov (United States)

Falk, M; Anderson, C D

2013-04-01

Sun exposure habits and the propensity to undertake sun protection differ between individuals. Not least in primary prevention of skin cancer, aiming at reducing ultraviolet (UV) exposure, knowledge about these factors may be of importance. The aim of the present study was to investigate, in a primary health care (PHC) population, the relationship between sun exposure habits/sun protection behaviour/readiness to increase sun protection and gender, age, educational level and skin UV-sensitivity. The baseline data from a previously performed RCT on skin cancer prevention was used. 415 patients, aged > 18 years, visiting a PHC centre in southern Sweden, filled-out a questionnaire mapping sun exposure, readiness to increase sun protection according to the Transtheoretical Model of Behaviour Change (TTM), and the above mentioned factors. Female gender was associated with more frequent suntanning (p protection. Subjects with low educational level reported less frequent sunscreen use than those with higher educational level, and also chose lower SPF (p skin UV-sensitivity was associated with markedly lower sun exposure (p protection. Females and subjects with high educational level reported higher readiness to increase sunscreen use than males and subjects with lower educational level (p skin type appear to be important factors affecting sun exposure habits and sun protection behaviour, which supports the idea of appropriate mapping of these factors in patients in order to individualise sun protection advice according to the individual patient situation and capabilities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Observing the Sun with NuSTAR

Science.gov (United States)

Kohler, Susanna

2016-07-01

The Nuclear Spectroscopic Telescope Array (NuSTAR) is a space telescope primarily designed to detect high-energy X-rays from faint, distant astrophysical sources. Recently, however, its occasionally been pointing much closer to home, with the goal of solving a few longstanding mysteries about the Sun.Intensity maps from an observation of a quiet-Sun region near the north solar pole and an active region just below the solar limb. The quiet-Sun data will be searched for small flares that could be heating the solar corona, and the high-altitude emission above the limb may provide clues about particle acceleration. [Adapted from Grefenstette et al. 2016]An Unexpected TargetThough we have a small fleet of space telescopes designed to observe the Sun, theres an important gap: until recently, there was no focusing telescope making solar observations in the hard X-ray band (above ~3 keV). Conveniently, there is a tool capable of doing this: NuSTAR.Though NuSTARs primary mission is to observe faint astrophysical X-ray sources, a team of scientists has recently conducted a series of observations in which NuSTAR was temporarily repurposed and turned to focus on the Sun instead.These observations pose an interesting challenge precisely because of NuSTARs extreme sensitivity: pointing at such a nearby, bright source can quickly swamp the detectors. But though the instrument cant be used to observe the bright flares and outbursts from the Sun, its the perfect tool for examining the parts of the Sun weve been unable to explore in hard X-rays before now such as faint flares, or the quiet, inactive solar surface.In a recently published study led by Brian Grefenstette (California Institute of Technology), the team describes the purpose and initial results of NuSTARs first observations of the Sun.Solar MysteriesWhat is NuSTAR hoping to accomplish with its solar observations? There are two main questions that hard X-ray observations may help to answer.How are particles accelerated in

Sun-Earth Day 2005: Ancient Observatories: Timeless Knowledge

Science.gov (United States)

Thieman, J. R.; Cline, T.; Lewis, E.; Hawkins, I.; Odenwald, S.; Mayo, L.

2005-05-01

The NASA Sun-Earth Connection Education Forum (SECEF) annually promotes an event called Sun-Earth Day. For Sun-Earth Day 2005 SECEF has selected a theme called "Ancient Observatories: Timeless Knowledge. This year's Sun-Earth Day theme is your ticket to a fascinating journey through time as we explore centuries of sun watching by a great variety of cultures. From ancient solar motion tracking to modern solar activity monitoring the Sun has always occupied an important spot in mankind's quest to understand the Universe. Sun-Earth Day events usually are centered on the spring equinox around March 21, but this year there has already been a webcast from the San Francisco Exploratorium and the Native American ruins at Chaco Canyon, New Mexico on the day of winter solstice 2004. There will be another webcast on March 20 live from Chichen Itza, Mexico highlighting the solar alignment that makes a serpent appear on one of the ancient pyramids. The website http://sunearthday.nasa.gov has been developed to provide the necessary resources and opportunities for participation by scientists and educators in giving school or general public programs about Sun-Earth Day. The goal is to involve as much of the student population and the public in this event as possible and to help them understand the importance of the Sun for ancient and modern peoples. Through engaging activities available on the website, classrooms and museums can create their own event or participate in one of the opportunities we make available. Scientists, educators, amateur astronomers, and museums are invited to register on the website to receive a free packet of materials about Sun-Earth Day for use in making presentations or programs about the event. Past and future Sun-Earth Days will be discussed as well.

Sun Proof

Centers for Disease Control (CDC) Podcasts

2012-10-23

In this podcast for kids, the Kidtastics talk about the harmful effects of the sun and how to protect yourself from it.  Created: 10/23/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 10/23/2012.

Revelation of the Sun Self-Similarity Skeletal Structures

International Nuclear Information System (INIS)

Rantsev-Kartinov, V.A.

2005-01-01

The analysis of databases of photographic images of a surface of the Sun, its atmosphere and the closest its space environment taken at various spatial resolutions and for various types of radiation of a surface of the Sun by means of a method multilevel dynamic contrasting, has revealed presence skeletal structures as on the Sun directly such and in its environment. It is demonstrated the revealed a global structures of the Sun and powerful ejections of mass of its corona, as well as the structures of its atmosphere, protuberances, sun-spots and a globular structures of its photosphere

Sun, weather, and climate

International Nuclear Information System (INIS)

Herman, J.R.; Goldberg, R.A.

1985-01-01

The general field of sun-weather/climate relationships that is, apparent weather and climate responses to solar activity is introduced and theoretical and experimental suggestions for further research to identify and investigate the unknown casual mechanisms are provided. Topics of discussion include: (1) solar-related correlation factors and energy sources; (2) long-term climate trends; (3) short-term meteorological correlations; (4) miscellaneous obscuring influences; (5) physical processes and mechanisms; (6) recapitulation of sun-weather relationships; and (7) guidelines for experiments. 300 references

Sun and Skin: The Dark Side of Sun Exposure

Science.gov (United States)

... a toll on your skin and its underlying connective tissue. As a result, your skin may develop more wrinkles and lines. Too much sun exposure can also raise your risk for skin cancer, the most common type of cancer in the ...

Sun, UV Radiation and Your Eyes

Science.gov (United States)

... Sunglasses Sun Smart UV Safety Infographic The Sun, UV Radiation and Your Eyes Leer en Español: El ... Aug. 28, 2014 Keep an Eye on Ultraviolet (UV) Safety Eye medical doctors (ophthalmologists) caution us that ...

Sun Exposure and Psychotic Experiences

Directory of Open Access Journals (Sweden)

Izabela Pilecka

2017-06-01

Full Text Available ObjectiveSun exposure is considered the single most important source of vitamin D. Vitamin D deficiency has been suggested to play a role in the etiology of psychotic disorders. The aim of the present study was to evaluate the association between sun exposure and psychotic experiences (PEs in a general population sample of Swedish women.MethodsThe study population included participants from The Swedish Women’s Lifestyle and Health cohort study. The 20-item community assessment of psychic experiences (CAPEs was administered between ages 30 and 50 to establish PEs. Sun exposure as measured by (1 sunbathing holidays and (2 history of sunburn was measured between ages 10 and 39. The association between sun exposure and PEs was evaluated by quantile regression models.Results34,297 women were included in the analysis. Women who reported no sunbathing holidays and 2 or more weeks of sunbathing holidays scored higher on the CAPE scale than women exposed to 1 week of sunbathing holidays across the entire distribution, when adjusting for age and education. Similarly, compared with women who reported a history of one sunburn, the women with none or two or more sunburns showed higher scores on the CAPE scale.ConclusionThe results of the present study suggest that, in a population-based cohort of middle aged women, both low and high sun exposure is associated with increased level of positive PEs.

The sun in time

International Nuclear Information System (INIS)

Sonett, C.P.; Giampapa, M.S.; Matthews, M.S.

1991-01-01

Various papers on solar science are presented. The topics considered include: variability of solar irradiance, sunspot number, solar diameter, and solar wind properties; theory of luminosity and radius variations; standard solar models; the sun and the IMF; variations of cosmic-ray flux with time; accelerated particles in solar flares; solar cosmic ray fluxes during the last 10 million yrs; solar neutrinos and solar history; time variations of Be-10 and solar activity; solar and terrestrial components of the atmospheric C-14 variation spectrum; solar flare heavy-ion tracks in extraterrestrial objects. Also addressed are: the faint young sun problem; atmospheric responses to solar irradiation; quaternary glaciations; solar-terrestrial relationships in recent sea sediments; magnetic history of the sun; pre- and main-sequence evolution of solar activity; magnetic activity in pre-main-sequence stars; classical T Tauri stars; relict magnetism of meteorites; luminosity variability of solar-type stars; evolution of angular momentum in solar-mass stars; time evolution of magnetic fields on solarlike stars

East–West GEO Satellite Station-Keeping with Degraded Thruster Response

Directory of Open Access Journals (Sweden)

Stoian Borissov

2015-09-01

Full Text Available The higher harmonic terms of Earth’s gravitational potential slowly modify the nominal longitude of geostationary Earth orbit (GEO satellites, while the third-body presence (Moon and Sun mainly affects their latitude. For this reason, GEO satellites periodically need to perform station-keeping maneuvers, namely, east–west and north–south maneuvers to compensate for longitudinal and latitudinal variations, respectively. During the operational lifetime of GEO satellites, the thrusters’ response when commanded to perform these maneuvers slowly departs from the original nominal impulsive behavior. This paper addresses the practical problem of how to perform reliable east–west station-keeping maneuvers when thruster response is degraded. The need for contingency intervention from ground-based satellite operators is reduced by breaking apart the scheduled automatic station-keeping maneuvers into smaller maneuvers. Orbital alignment and attitude are tracked on-board during and in between sub-maneuvers, and any off nominal variations are corrected for with subsequent maneuvers. These corrections are particularly important near the end of the lifetime of GEO satellites, where thruster response is farthest from nominal performance.

Heating the Chromosphere in the Quiet Sun

Science.gov (United States)

Kohler, Susanna

2018-04-01

The best-studied star the Sun still harbors mysteries for scientists to puzzle over. A new study has now explored the role of tiny magnetic-field hiccups in an effort to explain the strangely high temperatures of the Suns upper atmosphere.Schematic illustrating the temperatures in different layers of the Sun. [ESA]Strange Temperature RiseSince the Suns energy is produced in its core, the temperature is hottest here. As expected, the temperature decreases further from the Suns core up until just above its surface, where it oddly begins to rise again. While the Suns surface is 6,000 K, the temperature is higher above this: 10,000 K in the outer chromosphere.So how is the chromosphere of the Sun heated? Its possible that the explanation can be found not amid high solar activity, but in quiet-Sun regions.In a new study led by Milan Goi (Lockheed Martin Solar and Astrophysics Laboratory, Bay Area Environmental Research Institute), a team of scientists has examined a process that quietly happens in the background: the cancellation of magnetic field lines in the quiet Sun.Activity in a SupergranuleTop left: SDO AIA image of part of the solar disk. The next three panels are a zoom of the particular quiet-Sun region that the authors studied, all taken with IRIS at varying wavelengths: 1400 (top right), 2796 (bottom left), and 2832 (bottom right). [Goi et al. 2018]The Sun is threaded by strong magnetic field lines that divide it into supergranules measuring 30 million meters across (more than double the diameter of Earth!). Supergranules may seem quiet inside, but looks can be deceiving: the interiors of supergranules contain smaller, transient internetwork fields that move about, often resulting in magnetic elements of opposite polarity encountering and canceling each other.For those internetwork flux cancellations that occur above the Suns surface, a small amount of energy could be released that locally heats the chromosphere. But though each individual event has a small

Sun and solar flares

Energy Technology Data Exchange (ETDEWEB)

McKenna-Lawlor, S. (Saint Patrick' s Coll., Maynooth (Ireland))

1982-07-01

The subject is discussed under the headings: the sun's core (thermonuclear reactions, energy transfer from core through radiation zone, convection zone, photosphere, chromosphere and corona); the photosphere (convection, granulation, sunspots, magnetic fields, solar cycle, rotation of the sun); solar variability and paleoclimatic records (correlation of low solar activity with increased /sup 14/C production in atmosphere); the chromosphere and corona (turbulence, temperature, coronal streamers, energy transfer); solar flares (cosmic rays, aurorae, spectra, velocity of flares, prominences, mechanisms of flares); the solar wind.

Nuclear astrophysics of the sun

International Nuclear Information System (INIS)

Kocharov, G.E.

1980-01-01

In the first chapter we will discuss the problem of nuclear reactions in the interior of the sun and consider the modern aspects of the neutrino astrophysics of the Sun. The second chapter is devoted to the high energy interactions in the solar atmosphere during the flares. Among a great number of events during the solar flares we shall consider mainly the nuclear reactions. Special attention will be paid to the genetic connection between the different components of solar electromagnetic and corpuscular radiation. The idea of the unity of processes in different parts of the Sun, from hot and dense interior up to the rare plasma of the solar corona will be the main line of the book. (orig./WL) 891 WL/orig.- 892 HIS

Pre-main-sequence evolution of the sun

International Nuclear Information System (INIS)

Gough, D.

1980-01-01

The phase of solar evolution after the dynamical collapse is considered. The physics of the Kelvin-Helmholtz phase of gravitational collapse is described, attention being given to the early stages of the star when it was completely convective. It is noted that subsequently, a radiative core developed and evolution was controlled by the rate at which heat can diffuse through it by radiative transfer. Since the study of the Kelvin-Helmholtz contraction alone does not give enough information regarding the state of the sun when it first settled down to approximate hydrostatic equilibrium, other stars are studied, and information on the sun is obtained by analogy. Many young solar-type stars, such as the T Tauri stars, are not in the completely convective Hayashi (1961) phase hence it is proposed that the sun was completely mixed soon after its formation, which has some bearing on the sun's chemical structure. It is suggested that the surface of the sun was very nonuniform compared with the photosphere of today. The simple solar evolution model presented gives a good guide to the general way in which the sun contracted to the main sequence

Our prodigal sun. [solar energy technology

Science.gov (United States)

1974-01-01

Characteristics of the sun are reported indicating it as a source of energy. Data from several space missions are discussed, and the solar activity cycle is presented. The corona, flares, prominences, spots, and wind of the sun are also discussed.

Precise nuclear physics for the sun

International Nuclear Information System (INIS)

Bemmerer, Daniel

2012-01-01

For many centuries, the study of the Sun has been an important testbed for understanding stars that are further away. One of the first astronomical observations Galileo Galilei made in 1612 with the newly invented telescope concerned the sunspots, and in 1814, Joseph von Fraunhofer employed his new spectroscope to discover the absorption lines in the solar spectrum that are now named after him. Even though more refined and new modes of observation are now available than in the days of Galileo and Fraunhofer, the study of the Sun is still high on the agenda of contemporary science, due to three guiding interests. The first is connected to the ages-old human striving to understand the structure of the larger world surrounding us. Modern telescopes, some of them even based outside the Earth's atmosphere in space, have succeeded in observing astronomical objects that are billions of light-years away. However, for practical reasons precision data that are important for understanding stars can still only be gained from the Sun. In a sense, the observations of far-away astronomical objects thus call for a more precise study of the closeby, of the Sun, for their interpretation. The second interest stems from the human desire to understand the essence of the world, in particular the elementary particles of which it consists. Large accelerators have been constructed to produce and collide these particles. However, man-made machines can never be as luminous as the Sun when it comes to producing particles. Solar neutrinos have thus served not only as an astronomical tool to understand the Sun's inner workings, but their behavior on the way from the Sun to the Earth is also being studied with the aim to understand their nature and interactions. The third interest is strictly connected to life on Earth. A multitude of research has shown that even relatively slight changes in the Earth's climate may strongly affect the living conditions in a number of densely populated areas

Precise nuclear physics for the sun

Energy Technology Data Exchange (ETDEWEB)

Bemmerer, Daniel

2012-07-01

For many centuries, the study of the Sun has been an important testbed for understanding stars that are further away. One of the first astronomical observations Galileo Galilei made in 1612 with the newly invented telescope concerned the sunspots, and in 1814, Joseph von Fraunhofer employed his new spectroscope to discover the absorption lines in the solar spectrum that are now named after him. Even though more refined and new modes of observation are now available than in the days of Galileo and Fraunhofer, the study of the Sun is still high on the agenda of contemporary science, due to three guiding interests. The first is connected to the ages-old human striving to understand the structure of the larger world surrounding us. Modern telescopes, some of them even based outside the Earth's atmosphere in space, have succeeded in observing astronomical objects that are billions of light-years away. However, for practical reasons precision data that are important for understanding stars can still only be gained from the Sun. In a sense, the observations of far-away astronomical objects thus call for a more precise study of the closeby, of the Sun, for their interpretation. The second interest stems from the human desire to understand the essence of the world, in particular the elementary particles of which it consists. Large accelerators have been constructed to produce and collide these particles. However, man-made machines can never be as luminous as the Sun when it comes to producing particles. Solar neutrinos have thus served not only as an astronomical tool to understand the Sun's inner workings, but their behavior on the way from the Sun to the Earth is also being studied with the aim to understand their nature and interactions. The third interest is strictly connected to life on Earth. A multitude of research has shown that even relatively slight changes in the Earth's climate may strongly affect the living conditions in a number of densely

jianhua sun

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences. JIANHUA SUN. Articles written in Journal of Biosciences. Volume 42 Issue 4 December 2017 pp 575-584 Article. MicroRNA-486-5p suppresses TGF-b2-induced proliferation, invasion and epithelial–mesenchymal transition of lens epithelial cells by targeting Smad2.

The sun and the neutrinos

International Nuclear Information System (INIS)

Forgacsne Dajka, E.

2000-01-01

A review of the solar neutrino puzzle is given. The main processes in the sun, the pp-chain and the CNO cycle are described. The solar neutrino puzzle, i.e. the fact that the detected amount of neutrinos coming from the sun is less than the amount predicted by the solar model is discussed. The first generation solar neutrino experiments are presented. (K.A.)

Case study: beverage temperature at aid stations in ironman triathlon.

Science.gov (United States)

Burdon, Catriona A; Johnson, Nathan A; Chapman, Phillip G; Munir Che Muhamed, Ahmad; O'Connor, Helen T

2013-08-01

The aim of this study was to measure the effect of environmental conditions and aid-station beverage- cooling practices on the temperature of competitor beverages. Environmental and beverage temperatures were measured at three cycling and two run course aid stations at the 2010 Langkawi, Malaysia (MA), and Port Macquarie, Australia (AU), Ironman triathlon events. To measure the specific effect of radiant temperature, additional fluid-filled (600 ml) drink bottles (n = 12) were cooled overnight (C) and then placed in direct sun (n = 6) or shade (n = 6) near to a cycle aid station at AU. During both events, beverage temperature increased over time (p beverage temperature ranged between 14-26°C and during both events was above the palatable range (15-22°C) for extended periods. At AU, bottles placed in direct sunlight heated faster (6.9 ± 2.3 °C·h-1) than those in the shade (4.8 ±1.1°C·h-1, p = .05). Simple changes to Ironman aid-station practices, including shade and chilling beverages with ice, result in the provision of cooler beverages. Future studies should investigate whether provision of cool beverages at prolonged endurance events influences heat-illness incidence, beverage-consumption patterns, and competitor performance.

SOHO starts a revolution in the science of the Sun

Science.gov (United States)

1996-07-01

In addition, SOHO has found clues to the forces that accelerate the solar wind of atomic particles blowing unceasingly through the Solar System. By relating the huge outbursts called coronal mass ejections to preceding magnetic changes in the Sun, SOHO scientists hope to predict such events which, in the Earth's vicinity, endanger power supplies and satellites. SOHO sees differences in the strength of the solar wind in various directions, by mapping a cavity in the cloud of interstellar hydrogen surrounding the Sun. As a bonus, SOHO secured remarkable images of Comet Hyakutake, by ultraviolet and visible light. The revolution in solar science will seem more complete when all the pieces and actions of the Sun, detected by twelve different instruments, are brought together in observations and concepts. Fundamental questions will then be open to re-examination, about the origin of the Sun's magnetism, the cause of its variations in the 11-year cycle of sunspot activity, and the consequences for the Solar System at large. SOHO is greater than the sum of its parts. "SOHO takes solar science by storm," says Roger Bonnet, the European Space Agency's Director of Science, "thanks to its combination of instruments. Unprecedented results from individual telescopes and spectrometers are impressive, of course, but what is breathtaking is SOHO's ability to explore the Sun all the way from its nuclear core to the Earth's vicinity and beyond. We can expect a completely new picture of how agitation inside the Sun, transmitted through the solar atmosphere, directly affects us on the Earth." SOHO is a project of international cooperation between the European Space Agency and NASA. The spacecraft was built in Europe and instrumented by scientists on both sides of the Atlantic. NASA launched SOHO and provides the ground stations and an operations centre at the Goddard Space Flight Center near Washington. SOHO has an uninterrupted view of the Sun from a halo orbit around Lagrangian

SunPy: Python for Solar Physics

Science.gov (United States)

Bobra, M.; Inglis, A. R.; Mumford, S.; Christe, S.; Freij, N.; Hewett, R.; Ireland, J.; Martinez Oliveros, J. C.; Reardon, K.; Savage, S. L.; Shih, A. Y.; Pérez-Suárez, D.

2017-12-01

SunPy is a community-developed open-source software library for solar physics. It is written in Python, a free, cross-platform, general-purpose, high-level programming language which is being increasingly adopted throughout the scientific community. SunPy aims to provide the software for obtaining and analyzing solar and heliospheric data. This poster introduces a new major release, SunPy version 0.8. The first major new feature introduced is Fido, the new primary interface to download data. It provides a consistent and powerful search interface to all major data providers including the VSO and the JSOC, as well as individual data sources such as GOES XRS time series. It is also easy to add new data sources as they become available, i.e. DKIST. The second major new feature is the SunPy coordinate framework. This provides a powerful way of representing coordinates, allowing simple and intuitive conversion between coordinate systems and viewpoints of different instruments (i.e., Solar Orbiter and the Parker Solar Probe), including transformation to astrophysical frames like ICRS. Other new features including new timeseries capabilities with better support for concatenation and metadata, updated documentation and example gallery. SunPy is distributed through pip and conda and all of its code is publicly available (sunpy.org).

Perfmon2: a leap forward in performance monitoring

International Nuclear Information System (INIS)

Jarp, S; Jurga, R; Nowak, A

2008-01-01

This paper describes the software component, perfmon2, that is about to be added to the Linux kernel as the standard interface to the Performance Monitoring Unit (PMU) on common processors, including x86 (AMD and Intel), Sun SPARC, MIPS, IBM Power and Intel Itanium. It also describes a set of tools for doing performance monitoring in practice and details how the CERN openlab team has participated in the testing and development of these tools

Perfmon2: a leap forward in performance monitoring

Energy Technology Data Exchange (ETDEWEB)

Jarp, S; Jurga, R; Nowak, A [CERN, Geneva (Switzerland)], E-mail: Sverre.Jarp@cern.ch

2008-07-15

This paper describes the software component, perfmon2, that is about to be added to the Linux kernel as the standard interface to the Performance Monitoring Unit (PMU) on common processors, including x86 (AMD and Intel), Sun SPARC, MIPS, IBM Power and Intel Itanium. It also describes a set of tools for doing performance monitoring in practice and details how the CERN openlab team has participated in the testing and development of these tools.

Perfmon2 a leap forward in performance monitoring

CERN Document Server

Jarp, S; Nowak, A

2008-01-01

This paper describes the software component, perfmon2, that is about to be added to the Linux kernel as the standard interface to the Performance Monitoring Unit (PMU) on common processors, including x86 (AMD and Intel), Sun SPARC, MIPS, IBM Power and Intel Itanium. It also describes a set of tools for doing performance monitoring in practice and details how the CERN openlab team has participated in the testing and development of these tools.

A software program for exchanging MR data

DEFF Research Database (Denmark)

Ring, P B; Jensen, J A; Henriksen, O

1993-01-01

of digital MR images of the human brain. Because there was no common data format, software package was developed for data exchange. This article describes the basic features of the developed software. The software package was written in the language of C and was successfully tested on an IBM-6150 UNIX...... workstation. The software is currently being tested on the following series of UNIX workstations: SUN SPARC, IBM RS6000, and HP 9000/700....

Perfmon2: a leap forward in performance monitoring

Science.gov (United States)

Jarp, S.; Jurga, R.; Nowak, A.

2008-07-01

This paper describes the software component, perfmon2, that is about to be added to the Linux kernel as the standard interface to the Performance Monitoring Unit (PMU) on common processors, including x86 (AMD and Intel), Sun SPARC, MIPS, IBM Power and Intel Itanium. It also describes a set of tools for doing performance monitoring in practice and details how the CERN openlab team has participated in the testing and development of these tools.

Multi-Aperture CMOS Sun Sensor for Microsatellite Attitude Determination

Directory of Open Access Journals (Sweden)

Michele Grassi

2009-06-01

Full Text Available This paper describes the high precision digital sun sensor under development at the University of Naples. The sensor determines the sun line orientation in the sensor frame from the measurement of the sun position on the focal plane. It exploits CMOS technology and an original optical head design with multiple apertures. This allows simultaneous multiple acquisitions of the sun as spots on the focal plane. The sensor can be operated either with a fixed or a variable number of sun spots, depending on the required field of view and sun-line measurement precision. Multiple acquisitions are averaged by using techniques which minimize the computational load to extract the sun line orientation with high precision. Accuracy and computational efficiency are also improved thanks to an original design of the calibration function relying on neural networks. Extensive test campaigns are carried out using a laboratory test facility reproducing sun spectrum, apparent size and distance, and variable illumination directions. Test results validate the sensor concept, confirming the precision improvement achievable with multiple apertures, and sensor operation with a variable number of sun spots. Specifically, the sensor provides accuracy and precision in the order of 1 arcmin and 1 arcsec, respectively.

The depth of the honeybee's backup sun-compass systems.

Science.gov (United States)

Dovey, Katelyn M; Kemfort, Jordan R; Towne, William F

2013-06-01

Honeybees have at least three compass mechanisms: a magnetic compass; a celestial or sun compass, based on the daily rotation of the sun and sun-linked skylight patterns; and a backup celestial compass based on a memory of the sun's movements over time in relation to the landscape. The interactions of these compass systems have yet to be fully elucidated, but the celestial compass is primary in most contexts, the magnetic compass is a backup in certain contexts, and the bees' memory of the sun's course in relation to the landscape is a backup system for cloudy days. Here we ask whether bees have any further compass systems, for example a memory of the sun's movements over time in relation to the magnetic field. To test this, we challenged bees to locate the sun when their known celestial compass systems were unavailable, that is, under overcast skies in unfamiliar landscapes. We measured the bees' knowledge of the sun's location by observing their waggle dances, by which foragers indicate the directions toward food sources in relation to the sun's compass bearing. We found that bees have no celestial compass systems beyond those already known: under overcast skies in unfamiliar landscapes, bees attempt to use their landscape-based backup system to locate the sun, matching the landscapes or skylines at the test sites with those at their natal sites as best they can, even if the matches are poor and yield weak or inconsistent orientation.

Sun, Moon and Earthquakes

Science.gov (United States)

Kolvankar, V. G.

2013-12-01

During a study conducted to find the effect of Earth tides on the occurrence of earthquakes, for small areas [typically 1000km X1000km] of high-seismicity regions, it was noticed that the Sun's position in terms of universal time [GMT] shows links to the sum of EMD [longitude of earthquake location - longitude of Moon's foot print on earth] and SEM [Sun-Earth-Moon angle]. This paper provides the details of this relationship after studying earthquake data for over forty high-seismicity regions of the world. It was found that over 98% of the earthquakes for these different regions, examined for the period 1973-2008, show a direct relationship between the Sun's position [GMT] and [EMD+SEM]. As the time changes from 00-24 hours, the factor [EMD+SEM] changes through 360 degree, and plotting these two variables for earthquakes from different small regions reveals a simple 45 degree straight-line relationship between them. This relationship was tested for all earthquakes and earthquake sequences for magnitude 2.0 and above. This study conclusively proves how Sun and the Moon govern all earthquakes. Fig. 12 [A+B]. The left-hand figure provides a 24-hour plot for forty consecutive days including the main event (00:58:23 on 26.12.2004, Lat.+3.30, Long+95.980, Mb 9.0, EQ count 376). The right-hand figure provides an earthquake plot for (EMD+SEM) vs GMT timings for the same data. All the 376 events including the main event faithfully follow the straight-line curve.

THE SUN WAS NOT BORN IN M67

International Nuclear Information System (INIS)

Pichardo, Bárbara; Moreno, Edmundo; Allen, Christine; Bedin, Luigi R.; Bellini, Andrea; Pasquini, Luca

2012-01-01

Using the most recent proper-motion determination of the old, solar-metallicity, Galactic open cluster M67 in orbital computations in a non-axisymmetric model of the Milky Way, including a bar and three-dimensional spiral arms, we explore the possibility that the Sun once belonged to this cluster. We have performed Monte Carlo numerical simulations to generate the present-day orbital conditions of the Sun and M67, and all the parameters in the Galactic model. We compute 3.5 × 10 5 pairs of orbits Sun-M67 looking for close encounters in the past with a minimum distance approach within the tidal radius of M67. In these encounters we find that the relative velocity between the Sun and M67 is larger than 20 km s –1 . If the Sun had been ejected from M67 with this high velocity by means of a three-body encounter, this interaction would have either destroyed an initial circumstellar disk around the Sun or dispersed its already formed planets. We also find a very low probability, much lower than 10 –7 , that the Sun was ejected from M67 by an encounter of this cluster with a giant molecular cloud. This study also excludes the possibility that the Sun and M67 were born in the same molecular cloud. Our dynamical results convincingly demonstrate that M67 could not have been the birth cluster of our solar system.

CRUQS: A Miniature Fine Sun Sensor for Nanosatellites

Science.gov (United States)

Heatwole, Scott; Snow, Carl; Santos, Luis

2013-01-01

A new miniature fine Sun sensor has been developed that uses a quadrant photodiode and housing to determine the Sun vector. Its size, mass, and power make it especially suited to small satellite applications, especially nanosatellites. Its accuracy is on the order of one arcminute, and it will enable new science in the area of nanosatellites. The motivation for this innovation was the need for high-performance Sun sensors in the nanosatellite category. The design idea comes out of the LISS (Lockheed Intermediate Sun Sensor) used by the sounding rocket program on their solar pointing ACS (Attitude Control System). This system uses photodiodes and a wall between them. The shadow cast by the Sun is used to determine the Sun angle. The new sensor takes this concept and miniaturizes it. A cruciform shaped housing and a surface-mount quadrant photodiode package allow for a two-axis fine Sun sensor to be packaged into a space approx.1.25xl x0.25 in. (approx.3.2x2.5x0.6 cm). The circuitry to read the photodiodes is a simple trans-impedance operational amplifier. This is much less complex than current small Sun sensors for nanosatellites that rely on photo-arrays and processing of images to determine the Sun center. The simplicity of the circuit allows for a low power draw as well. The sensor consists of housing with a cruciform machined in it. The cruciform walls are 0.5-mm thick and the center of the cruciform is situated over the center of the quadrant photodiode sensor. This allows for shadows to be cast on each of the four photodiodes based on the angle of the Sun. A simple operational amplifier circuit is used to read the output of the photodiodes as a voltage. The voltage output of each photodiode is summed based on rows and columns, and then the values of both rows or both columns are differenced and divided by the sum of the voltages for all four photodiodes. The value of both difference over sums for the rows and columns is compared to a table or a polynomial fit

yimin sun

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. YIMIN SUN. Articles written in Journal of Genetics. Volume 96 Issue 4 September 2017 pp 687-693 RESEARCH NOTE. The association study of nonsyndromic cleft lip with or without cleft palate identified risk variants of the GLI3 gene in a Chinese population · YIRUI WANG YIMIN SUN ...

Occupational sun protection: workplace culture, equipment provision and outdoor workers' characteristics.

Science.gov (United States)

Reeder, Anthony I; Gray, Andrew; McCool, Judith P

2013-01-01

The aim of this study was to describe outdoor workers' sun-protective practices, workplace sun-safety culture and sun-protective equipment provision; investigate the association of demographic, personal and occupational factors with sun-protective practices; and identify potential strategies for improving workers' sun protection. The present study used a clustered survey design with randomly identified employers in nine occupations. Employees provided questionnaire measures of demographics, personal characteristics (skin type, skin cancer risk perceptions, tanning attitudes, sun-exposure knowledge), personal occupational sun protection practices (exposure reduction, use of sun-protective clothing, sunscreen and shade), workplace sun-protective equipment provision and perceived workplace sun-safety culture. Summative scores were calculated for attitudes, knowledge, workplace provision and culture. A multivariable model was built with worker and workplace variables as plausible predictors of personal sun protection. In this study, 1,061 workers (69% participation) from 112 workplaces provided sufficient information for analysis. Sex, age, prioritized ethnicity, education and risk perception differed significantly between occupational groups (pworkplace sun-protection equipment provision and supportive culture. After adjustment, each one-point increase in Workplace Sun-safety Culture 2013Score (range 12 points) was associated with a 0.16 higher Personal Sun-Protection Score (pWorkplace Provision Score (range 4 points) was associated with a 0.14 higher score (pworkplace culture are promising components for the development of comprehensive programmes to improve outdoor workers' sun-protective practices.

Piece of the sun

CERN Document Server

Wayne, Teddy

2015-01-01

Our rapidly industrialising world has an insatiable hunger for energy, and conventional sources are struggling to meet demand. Oil is running out, coal is damaging our climate, many nations are abandoning nuclear, yet solar, wind and water will never be a complete replacement. The solution, says Daniel Clery in this deeply researched and revelatory book, is to be found in the original energy source: the Sun itself. There, at its centre, the fusion of 630 million tonnes of hydrogen every second generates an unfathomable amount of energy. By replicating even a tiny piece of the Sun's power

The validated sun exposure questionnaire

DEFF Research Database (Denmark)

Køster, B; Søndergaard, J; Nielsen, J B

2017-01-01

Few questionnaires used in monitoring sun-related behavior have been tested for validity. We established criteria validity of a developed questionnaire for monitoring population sun-related behavior. During May-August 2013, 664 Danes wore a personal electronic UV-dosimeter for one week...... that measured the outdoor time and dose of erythemal UVR exposure. In the following week, they answered a questionnaire on their sun-related behavior in the measurement week. Outdoor time measured by dosimetry correlated strongly with both outdoor time and the developed exposure scale measured...... in the questionnaire. Exposure measured in SED by dosimetry correlated strongly with the exposure scale. In a linear regression model of UVR (SED) received, 41 percent of the variation was explained by skin type, age, week of participation and the exposure scale, with the exposure scale as the main contributor...

Torsional oscillations of the sun

International Nuclear Information System (INIS)

Snodgrass, H.B.; Howard, R.; National Solar Observatory, Tucson, AZ)

1985-01-01

The sun's differential rotation has a cyclic pattern of change that is tightly correlated with the sunspot, or magnetic activity, cycle. This pattern can be described as a torsional oscillation, in which the solar rotation is periodically sped up or slowed down in certain zones of latitude while elsewhere the rotation remains essentially steady. The zones of anomalous rotation move on the sun in wavelike fashion, keeping pace with and flanking the zones of magnetic activity. It is uncertain whether this torsional oscillation is a globally coherent ringing of the sun or whether it is a local pattern caused by and causing local changes in the magnetic fields. In either case, it may be an important link in the connection between the rotation and the cycle that is widely believed to exist but is not yet understood. 46 references

The sun and space weather Second Edition

CERN Document Server

Hanslmeier, Arnold

2007-01-01

This second edition is a great enhancement of literature which will help the reader get deeper into the specific topics. There are new sections included such as space weather data sources and examples, new satellite missions, and the latest results. At the end a comprehensive index is given which will allow the reader to quickly find his topics of interest. The Sun and Space weather are two rapidly evolving topics. The importance of the Sun for the Earth, life on Earth, climate and weather processes was recognized long ago by the ancients. Now, for the first time there is a continuous surveillance of solar activity at nearly all wavelengths. These data can be used to improve our understanding of the complex Sun-Earth interaction. The first chapters of the book deal with the Sun as a star and its activity phenomena as well as its activity cycle in order to understand the complex physics of the Sun-Earth system. The reader will see that there are many phenomena but still no definite explanations and models exis...

Preliminary safety analysis report for project 89-GEB-610 Plutonium Finishing Plant instrumentation upgrade. Revision 1

International Nuclear Information System (INIS)

Huber, T.E.

1995-01-01

This document consists of an analysis of the MICON system upgrade. This project shall install a Micon Co. distributed process monitor and control system with Sparc Sun workstation operator interfaces. The Sparc workstations are housed in consoles custom designed to human factors specifications. The distributed control system (DCS) shall have the installed capacity to monitor and control all related instruments and equipment presently connected to the panels in the PFP Power Control Room 321A as listed in the input/output list. This also includes all devices monitored and controlled by the 2736-ZB Allen Bradley programmable logic controller. The system has since assumed the control and monitoring responsibilities for Projects B- 680H ''Low Level Waste Treatment Facility'' and C-031H ''PFP Liquid Effluent Facilities''. Part of the new en's change area in Building 234-5ZA, Room 712, has been remodeled to house two consoles and one supervisor console. Local control units containing the microprocontrollers and the input/output interface circuit boards shall be wired to the instrumentation and controlled equipment. These units communicate with the Sparc workstations via a redundant data communications highway and shall be strategic, throughout the PFP facility. The DCS has already been purchased from Micon Co., located in Houston Texas, presently on site

Space Station alpha joint bearing

Science.gov (United States)

Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

1987-01-01

Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

A Small Spacecraft Swarm Deployment and Stationkeeping Strategy for Sun-Earth L1 Halo Orbits

Science.gov (United States)

Renea Conn, Tracie; Bookbinder, Jay

2018-01-01

Spacecraft orbits about the Sun-Earth librarian point L1 have been of interest since the 1950s. An L1 halo orbit was first achieved with the International Sun-Earth Explorer-3 (ISEE-3) mission, and similar orbits around Sun-Earth L1 were achieved in the Solar and Heliospheric Observatory (SOHO), Advanced Composition Explorer (ACE), Genesis, and Deep Space Climate Observatory (DSCOVR) missions. With recent advancements in CubeSat technology, we envision that it will soon be feasible to deploy CubeSats at L1. As opposed to these prior missions where one large satellite orbited alone, a swarm of CubeSats at L1 would enable novel science data return, providing a topology for intersatellite measurements of heliophysics phenomena both spatially and temporally, at varying spatial scales.The purpose of this iPoster is to present a flight dynamics strategy for a swarm of numerous CubeSats orbiting Sun-Earth L1. The presented method is a coupled, two-part solution. First, we present a deployment strategy for the CubeSats that is optimized to produce prescribed, time-varying intersatellite baselines for the purposes of collecting magnetometer data as well as radiometric measurements from cross-links. Second, we employ a loose control strategy that was successfully applied to SOHO and ACE for minimized stationkeeping propellant expenditure. We emphasize that the presented solution is practical within the current state-of-the-art and heritage CubeSat technology, citing capabilities of CubeSat designs that will launch on the upcoming Exploration Mission 1 (EM-1) to lunar orbits and beyond. Within this iPoster, we present animations of the simulated deployment strategy and resulting spacecraft trajectories. Mission design parameters such as total Δv required for long-term station keeping and minimum/maximum/mean spacecraft separation distances are also presented.

Sun exposure and protection behavior of Danish farm children

DEFF Research Database (Denmark)

Bodekær, Mette; Øager Petersen, Bibi; Philipsen, Peter Alshede

2014-01-01

families) kept daily sun behavior diaries (sun exposure, sunscreen use, sunburns) over a 4-month summer period (15,985 diary days). The Pigment Protection Factor (PPF), an objective measure of sun exposure, was measured at two body sites, before and after summer. All participants presented data from...... the same 115 days. Risk behavior (sun exposure of upper body) took place on 9.5 days (boys) and 15.6 days (girls). Sunburn and sunscreen use were infrequent. Boys' sun exposure resulted in an increased photo protection over the study period of 1.7 SED (upper arm) and 0.8 SED (shoulder) to elicit erythema...

Effects of Inner Nuclear Membrane Proteins SUN1/UNC-84A and SUN2/UNC-84B on the Early Steps of HIV-1 Infection.

Science.gov (United States)

Schaller, Torsten; Bulli, Lorenzo; Pollpeter, Darja; Betancor, Gilberto; Kutzner, Juliane; Apolonia, Luis; Herold, Nikolas; Burk, Robin; Malim, Michael H

2017-10-01

Human immunodeficiency virus type 1 (HIV-1) infection of dividing and nondividing cells involves regulatory interactions with the nuclear pore complex (NPC), followed by translocation to the nucleus and preferential integration into genomic areas in proximity to the inner nuclear membrane (INM). To identify host proteins that may contribute to these processes, we performed an overexpression screen of known membrane-associated NE proteins. We found that the integral transmembrane proteins SUN1/UNC84A and SUN2/UNC84B are potent or modest inhibitors of HIV-1 infection, respectively, and that suppression corresponds to defects in the accumulation of viral cDNA in the nucleus. While laboratory strains (HIV-1 NL4.3 and HIV-1 IIIB ) are sensitive to SUN1-mediated inhibition, the transmitted founder viruses RHPA and ZM247 are largely resistant. Using chimeric viruses, we identified the HIV-1 capsid (CA) protein as a major determinant of sensitivity to SUN1, and in vitro -assembled capsid-nucleocapsid (CANC) nanotubes captured SUN1 and SUN2 from cell lysates. Finally, we generated SUN1 -/- and SUN2 -/- cells by using CRISPR/Cas9 and found that the loss of SUN1 had no effect on HIV-1 infectivity, whereas the loss of SUN2 had a modest suppressive effect. Taken together, these observations suggest that SUN1 and SUN2 may function redundantly to modulate postentry, nuclear-associated steps of HIV-1 infection. IMPORTANCE HIV-1 causes more than 1 million deaths per year. The life cycle of HIV-1 has been studied extensively, yet important steps that occur between viral capsid release into the cytoplasm and the expression of viral genes remain elusive. We propose here that the INM components SUN1 and SUN2, two members of the linker of nucleoskeleton and cytoskeleton (LINC) complex, may interact with incoming HIV-1 replication complexes and affect key steps of infection. While overexpression of these proteins reduces HIV-1 infection, disruption of the individual SUN2 and SUN1 genes

The Sun in Time: Activity and Environment

Directory of Open Access Journals (Sweden)

Güdel Manuel

2007-12-01

Full Text Available The Sun's magnetic activity has steadily declined during its main-sequence life. While the solar photospheric luminosity was about 30% lower 4.6 Gyr ago when the Sun arrived on the main sequence compared to present-day levels, its faster rotation generated enhanced magnetic activity; magnetic heating processes in the chromosphere, the transition region, and the corona induced ultraviolet, extreme-ultraviolet, and X-ray emission about 10, 100, and 1000 times, respectively, the present-day levels, as inferred from young solar-analog stars. Also, the production rate of accelerated, high-energy particles was orders of magnitude higher than in present-day solar flares, and a much stronger wind escaped from the Sun, permeating the entire solar system. The consequences of the enhanced radiation and particle fluxes from the young Sun were potentially severe for the evolution of solar-system planets and moons. Interactions of high-energy radiation and the solar wind with upper planetary atmospheres may have led to the escape of important amounts of atmospheric constituents. The present dry atmosphere of Venus and the thin atmosphere of Mars may be a product of early irradiation and heating by solar high-energy radiation. High levels of magnetic activity are also inferred for the pre-main sequence Sun. At those stages, interactions of high-energy radiation and particles with the circumsolar disk in which planets eventually formed were important. Traces left in meteorites by energetic particles and anomalous isotopic abundance ratios in meteoritic inclusions may provide evidence for a highly active pre-main sequence Sun. The present article reviews these various issues related to the magnetic activity of the young Sun and the consequent interactions with its environment. The emphasis is on the phenomenology related to the production of high-energy photons and particles. Apart from the activity on the young Sun, systematic trends applicable to the entire

Essential Outdoor Sun Safety Tips for Winter

Science.gov (United States)

... Weekend Warriors expand/collapse Vitamin D Essential Outdoor Sun Safety Tips for Winter Winter sports enthusiasts are ... skiing! Be Mindful of Time Spent in the Sun, Regardless of the Season If possible, ski early ...

Population and age-group trends in weekend sun protection and sunburn over two decades of the SunSmart programme in Melbourne, Australia.

Science.gov (United States)

Makin, J K; Warne, C D; Dobbinson, S J; Wakefield, M A; Hill, D J

2013-01-01

In response to the high skin cancer burden in Australia, the multicomponent, community-wide SunSmart programme has worked since 1988 to reduce excessive sun exposure.  To examine trends in key sun-protection behaviours and sunburn for the Melbourne population from 1987 to 2007, and examine for the first time patterns of change among age groups.   Representative cross-sectional weekly telephone surveys of weekend sun protection and sunburn were conducted over 11 of the summers in the period 1987-88 to 2006-07. Trends were analysed for the population and for age groups, adjusting for ambient temperature and ultraviolet radiation, which are environmental determinants of sun-related behaviour and sunburn.   The general pattern of trends suggests two distinct periods, one with rapid improvement in behaviours (more sunscreen use, less unprotected body exposure and less sunburn) from 1987-88 to 1994-95, and the second from 1997-98 to 2006-07 with fewer changes in behaviours noted. The age-group analyses showed a similar pattern of change over time across groups, with a few notable exceptions.  The similarity of the pattern of trends among age groups suggests that external influences including the SunSmart programme's activity had a relatively similar impact across the population. Sun-related behaviours continue to be amenable to change. More recent relative stability with some declines in sun protection suggests further intensive campaigns and other strategies may be needed to maintain previous successes and to achieve more universal use of sun protection. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

ACTIVITY-BRIGHTNESS CORRELATIONS FOR THE SUN AND SUN-LIKE STARS

International Nuclear Information System (INIS)

Preminger, D. G.; Chapman, G. A.; Cookson, A. M.

2011-01-01

We analyze the effect of solar features on the variability of the solar irradiance in three different spectral ranges. Our study is based on two solar-cycles' worth of full-disk photometric images from the San Fernando Observatory, obtained with red, blue, and Ca II K-line filters. For each image we measure the photometric sum, Σ, which is the relative contribution of solar features to the disk-integrated intensity of the image. The photometric sums in the red and blue continuum, Σ r and Σ b , exhibit similar temporal patterns: they are negatively correlated with solar activity, with strong short-term variability, and weak solar-cycle variability. However, the Ca II K-line photometric sum, Σ K , is positively correlated with solar activity and has strong variations on solar-cycle timescales. We show that we can model the variability of the Sun's bolometric flux as a linear combination of Σ r and Σ K . We infer that, over solar-cycle timescales, the variability of the Sun's bolometric irradiance is directly correlated with spectral line variability, but inversely correlated with continuum variability. Our blue and red continuum filters are quite similar to the Stroemgren b and y filters used to measure stellar photometric variability. We conclude that active stars whose visible continuum brightness varies inversely with activity, as measured by the Ca HK index, are displaying a pattern that is similar to that of the Sun, i.e., radiative variability in the visible continuum that is spot-dominated.

No smoking guns under the Sun

CERN Document Server

CERN. Geneva

2000-01-01

The Sun is a typical main sequence star that generates its energy via the fusion of hydrogen into helium in two chains of nuclear reactions: the so-called pp chain and the CNO chain. If the nucleon number, electric charge, lepton flavour and energy are conserved and the Sun is in a steady state, then the total solar neutrino flux is fixed, to a good approximation, by the solar luminosity (approximately 65 billion neutrinos/cm2/s at Earth), independent of the specific nuclear reactions that power the Sun and produce neutrinos by beta decay or the electron capture of reaction products. The neutrinos from the dominant pp chain are produced by the beta decay of proton pairs (pp), boron-8 and lithium-4, and by electron capture by pp pairs and beryllium-7. Their spectra can be measured directly in the laboratory or calculated from the standard theory of electroweak interactions. To a very good approximation, they are independent of the conditions in the Sun. Only their relative contributions depend on the detailed ...

Software Defined GPS Receiver for International Space Station

Science.gov (United States)

Duncan, Courtney B.; Robison, David E.; Koelewyn, Cynthia Lee

2011-01-01

JPL is providing a software defined radio (SDR) that will fly on the International Space Station (ISS) as part of the CoNNeCT project under NASA's SCaN program. The SDR consists of several modules including a Baseband Processor Module (BPM) and a GPS Module (GPSM). The BPM executes applications (waveforms) consisting of software components for the embedded SPARC processor and logic for two Virtex II Field Programmable Gate Arrays (FPGAs) that operate on data received from the GPSM. GPS waveforms on the SDR are enabled by an L-Band antenna, low noise amplifier (LNA), and the GPSM that performs quadrature downconversion at L1, L2, and L5. The GPS waveform for the JPL SDR will acquire and track L1 C/A, L2C, and L5 GPS signals from a CoNNeCT platform on ISS, providing the best GPS-based positioning of ISS achieved to date, the first use of multiple frequency GPS on ISS, and potentially the first L5 signal tracking from space. The system will also enable various radiometric investigations on ISS such as local multipath or ISS dynamic behavior characterization. In following the software-defined model, this work will create a highly portable GPS software and firmware package that can be adapted to another platform with the necessary processor and FPGA capability. This paper also describes ISS applications for the JPL CoNNeCT SDR GPS waveform, possibilities for future global navigation satellite system (GNSS) tracking development, and the applicability of the waveform components to other space navigation applications.

Triana Safehold: A New Gyroless, Sun-Pointing Attitude Controller

Science.gov (United States)

Chen, J.; Morgenstern, Wendy; Garrick, Joseph

2001-01-01

Triana is a single-string spacecraft to be placed in a halo orbit about the sun-earth Ll Lagrangian point. The Attitude Control Subsystem (ACS) hardware includes four reaction wheels, ten thrusters, six coarse sun sensors, a star tracker, and a three-axis Inertial Measuring Unit (IMU). The ACS Safehold design features a gyroless sun-pointing control scheme using only sun sensors and wheels. With this minimum hardware approach, Safehold increases mission reliability in the event of a gyroscope anomaly. In place of the gyroscope rate measurements, Triana Safehold uses wheel tachometers to help provide a scaled estimation of the spacecraft body rate about the sun vector. Since Triana nominally performs momentum management every three months, its accumulated system momentum can reach a significant fraction of the wheel capacity. It is therefore a requirement for Safehold to maintain a sun-pointing attitude even when the spacecraft system momentum is reasonably large. The tachometer sun-line rate estimation enables the controller to bring the spacecraft close to its desired sun-pointing attitude even with reasonably high system momentum and wheel drags. This paper presents the design rationale behind this gyroless controller, stability analysis, and some time-domain simulation results showing performances with various initial conditions. Finally, suggestions for future improvements are briefly discussed.

The quiet Sun brightness temperature at 408 MHz

International Nuclear Information System (INIS)

Avignon, Y.; Lantos, P.; Palagi, F.; Patriarchi, P.

1975-01-01

The flux of the radio quiet Sun and the brightness temperature at 408 MHz (73cm) are derived from measurements with the E-W Nancay interferometer and the E-W arm of the Medicina North Cross. It is shown that the lowest envelopes, which defined the radio quiet Sun, correspond to transits of extended coronal holes across the disk of the Sun. (Auth.)

Structural insights into SUN-KASH complexes across the nuclear envelope

Institute of Scientific and Technical Information of China (English)

Wenjia Wang; Zhaocai Zhou; Zhubing Shi; Shi Jiao; Cuicui Chen; Huizhen Wang; Guoguang Liu; Qiang Wang; Yun Zhao; Mark I Greene

2012-01-01

Linker of the nucleoskeleton and the cytoskeleton (LINC) complexes are composed of SUN and KASH domaincontaining proteins and bridge the inner and outer membranes of the nuclear envelope.LINC complexes play critical roles in nuclear positioning,cell polarization and cellular stiffness.Previously,we reported the homotrimeric structure of human SUN2.We have now determined the crystal structure of the human SUN2-KASH complex.In the complex structure,the SUN domain homotrimer binds to three independent "hook"-like KASH peptides.The overall conformation of the SUN domain in the complex closely resembles the SUN domain in its apo state.A major conformational change involves the AA'-loop of KASH-bound SUN domain,which rearranges to form a mini β-sheet that interacts with the KASH peptide.The PPPT motif of the KASH domain fits tightly into a hydrophobic pocket on the homotrimeric interface of the SUN domain,which we termed the BI-pocket.Moreover,two adjacent protomers of the SUN domain homotrimer sandwich the KASH domain by hydrophobic interaction and hydrogen bonding.Mutations of these binding sites disrupt or reduce the association between the SUN and KASH domains in vitro.In addition,transfection of wild-type,but not mutant,SUN2 promotes cell migration in Ovcar-3 cells.These results provide a structural model of the LINC complex,which is essential for additional study of the physical and functional coupling between the cytoplasm and the nucleoplasm.

SOHO sees right through the Sun, and finds sunspots on the far side

Science.gov (United States)

2000-03-01

, helioseismologists detect many different modes of vibration appearing at the Sun's surface, all with tales to tell about how the interior is structured and how the gas moves about. The SOHO spacecraft is an ideal platform for helioseismology because its station 1.5 million kilometres out in space allows it to watch the Sun for 24 hours a day. Its own motions are very gentle -- an important consideration when scientists are looking for subtle motions on the Sun's surface. Developed and operated by a Californian team, the MDI instrument is the most elaborate of three helioseismic instruments on SOHO. It measures rhythmic motions at a million points across the Sun's visible surface. Computers can interpret the motions in terms of sound waves travelling through the Sun. The waves are affected by the various layers and movements of gas that they encounter. MDI has already revealed many unknown features of the interior, including layers where the speed of the gas changes abruptly and hidden jet streams circling the Sun's poles. The team is also discovering what goes on underneath sunspots on the near side of the Sun. Philip Scherrer of Stanford University, California, leads the MDI team. He is gratified but not surprised that his instrument has chalked up another success, with the detection of sunspots on the far side. "Up till now we've explored the Sun's interior quite thoroughly from the near surface down to the core," Scherrer commented. "Charlie Lindsey and Doug Braun told me many years ago how they hoped to use MDI on SOHO to see all the way to the far side. I was always sure they could do it." The technique of helioseismic holography used by Lindsey and Braun examines a wide ring of sound waves that emanate from a small region on the far side, and reach the near side by rebounding internally from the solar surface. A sunspot group reveals itself because the Sun's surface is depressed and very strong magnetic fields speed up the sound waves. As a result the sound waves arrive at the

The Sun/Earth System and Space Weather

Science.gov (United States)

Poland, Arthur I.; Fox, Nicola; Lucid, Shannon

2003-01-01

Solar variability and solar activity are now seen as significant drivers with respect to the Earth and human technology systems. Observations over the last 10 years have significantly advanced our understanding of causes and effects in the Sun/Earth system. On a practical level the interactions between the Sun and Earth dictate how we build our systems in space (communications satellites, GPS, etc), and some of our ground systems (power grids). This talk will be about the Sun/Earth system: how it changes with time, its magnetic interactions, flares, the solar wind, and how the Sun effects human systems. Data will be presented from some current spacecraft which show, for example, how we are able to currently give warnings to the scientific community, the Government and industry about space storms and how this data has improved our physical understanding of processes on the Sun and in the magnetosphere. The scientific advances provided by our current spacecraft has led to a new program in NASA to develop a 'Space Weather' system called 'Living With a Star'. The current plan for the 'Living With a Star' program will also be presented.

Deterministic chaos in the processor load

International Nuclear Information System (INIS)

Halbiniak, Zbigniew; Jozwiak, Ireneusz J.

2007-01-01

In this article we present the results of research whose purpose was to identify the phenomenon of deterministic chaos in the processor load. We analysed the time series of the processor load during efficiency tests of database software. Our research was done on a Sparc Alpha processor working on the UNIX Sun Solaris 5.7 operating system. The conducted analyses proved the presence of the deterministic chaos phenomenon in the processor load in this particular case

Vortices in the SU(N) x SU(N) spin systems in two dimensions

International Nuclear Information System (INIS)

Kares, R.J.D.

1982-01-01

The SU(N) x SU(N) or chiral spin systems in two dimensions with spin variables in both the fundamental and the adjoint representations of SU(N) are considered. In the adjoint representation the chiral models are found to possess topologically stable, classical vortex solutions which carry a Z(N) topological charge. A relationship is established between the chiral models and massive Yang-Mills theory in two dimensions. This relationship is exploited to prove the asymptotic freedom of the chiral models and to find their weak coupling mass gap. The connection between the vortices of the chiral models and those of the massive Yang-Mills theory is discussed. The behavior of a gas of vortices in the SU(2) chiral model is considered. This gas is converted to an equivalent field theory and studied using the renormalization group. It is shown that the SU(2) vortex gas does not undergo a Kosterlitz-Thouless phase transition. This behavior probably persists for the higher SU(N) groups as well. Finally, using the massive Yang-Mills theory the effect of the coupling of vortices to spin wave fluctuations is investigated. It is argued that as a result of the vortex-spin wave interaction the vortices acquire a mass scale dynamically. A self consistency condition is derived for the vortex scale and used to compute the mass gap for the chiral models in the presence of vortices. The mass gap obtained in this way is found to be in agreement with the weak coupling result suggesting that vortices may be responsible for generating the mass gap in the chiral models near T = 0

The sun and solar flares

International Nuclear Information System (INIS)

McKenna-Lawlor, S.

1982-01-01

The subject is discussed under the headings: the sun's core (thermonuclear reactions, energy transfer from core through radiation zone, convection zone, photosphere, chromosphere and corona); the photosphere (convection, granulation, sunspots, magnetic fields, solar cycle, rotation of the sun); solar variability and paleoclimatic records (correlation of low solar activity with increased 14 C production in atmosphere); the chromosphere and corona (turbulence, temperature, coronal streamers, energy transfer); solar flares (cosmic rays, aurorae, spectra, velocity of flares, prominences, mechanisms of flares); the solar wind. (U.K.)

Grand Minima: Is The Sun Going To Sleep?

Science.gov (United States)

Mcintosh, S. W.; Leamon, R. J.

2014-12-01

We explore recent observational work which indicate that the energetics of the sun's outer atmosphere have been on a steady decline for the past decade and perhaps longer. Futher, we show that new investigations into evolution of the Sun's global magnetic activity appear to demonstrate a path through which the Sun can go into, and exit from, a grand activity minimum without great difficulty while retaining an activity cycle - only losing sunspots. Are we at the begining of a new grand(-ish) minimum? Naturally, only time will tell, but the observational evidence hint that one may not be far off to what impact on the Sun-Earth Connection.

Knowledge and Practice of Sun Protection in Schools in South Africa Where No National Sun Protection Programme Exists

Science.gov (United States)

Wright, Caradee Y.; Reeder, Anthony I.; Albers, Patricia N.

2016-01-01

Interventions in primary schools that increase sun-protective behaviours and decrease ultraviolet radiation exposure, sunburn incidence and skin cancer risk can be effective. SunSmart School Accreditation Programmes (SSAP) are recommended. Prior to SSAP implementation in South Africa, we explored the feasibility of obtaining national baseline…

From 1 Sun to 10 Suns c-Si Cells by Optimizing Metal Grid, Metal Resistance, and Junction Depth

International Nuclear Information System (INIS)

Chaudhari, V.A.; Solanki, C.S.

2009-01-01

Use of a solar cell in concentrator PV technology requires reduction in its series resistance in order to minimize the resistive power losses. The present paper discusses a methodology of reducing the series resistance of a commercial c-Si solar cell for concentrator applications, in the range of 2 to 10 suns. Step by step optimization of commercial cell in terms of grid geometry, junction depth, and electroplating of the front metal contacts is proposed. A model of resistance network of solar cell is developed and used for the optimization. Efficiency of un optimized commercial cell at 10 suns drops by 30% of its 1 sun value corresponding to resistive power loss of about 42%. The optimized cell with grid optimization, junction optimization, electroplating, and junction optimized with electroplated contacts cell gives resistive power loss of 20%, 16%, 11%, and 8%, respectively. An efficiency gain of 3% at 10 suns for fully optimized cell is estimated

Ineffectiveness of sun awareness posters in dermatology clinics.

Science.gov (United States)

Jung, G W; Senthilselvan, A; Salopek, T G

2010-06-01

Although sun awareness posters have been used in doctors' offices and clinics for decades to promote sun protective behaviour, there is no evidence of their usefulness. To investigate whether sun awareness posters lead to inquiry of skin cancer and sun protection measures. Patients considered at risk for skin cancer seen at a dermatology clinic were randomly asked to complete a questionnaire designed to assess the effectiveness of three different sun awareness posters placed in patient rooms. The posters were selected on the basis of their catchy slogan and eye-appealing images, and included those featuring parental interest, sex appeal and informative advice. Only half of the patients noticed the posters (50.6%). The poster with sex appeal garnered the most attention (67.8%), followed by the informative poster (49.2%) and the parental interest poster (35.8%) (P poster inquired about cutaneous cancers and sun protection practices twice as often as those who did not notice the poster, only one-tenth of such inquiries were attributed to the poster ( approximately 5% of the target population). As reported in the questionnaire, the posters themselves were less effective than the advice of physicians in influencing patient attitudes towards sun protection measures. Organizations that produce and disseminate posters should consider beyond focus groups when they design their posters and should consider field testing their products to ensure that they are reaching the targeted audience and are having the expected beneficial effect, otherwise their posters are simply decorative.

Australian primary school communities' understandings of SunSmart: a qualitative study.

Science.gov (United States)

Winslade, Matthew; Wright, Bradley; Dudley, Dean; Cotton, Wayne; Brown, Alexandra

2017-10-01

Skin cancer represents a major health issue for Australia. Childhood sun exposure is an important risk factor and evidence suggests the use of sun protection measures by Australian school children could be improved. This study examines how the SunSmart Program, a school-based skin cancer prevention resource, can be supported to further increase sun protection behaviours to assist in lowering skin cancer incidence. The Health Promoting Schools (HPS) framework was adopted to select key stakeholders from a convenience sample of five school communities. Students, teaching staff and parents participated in semi-structured focus group and individual interviews. A thematic analysis was used to extract key themes from the data. Although these school communities were aware of sun protection practices and the risks associated with sun exposure, their understandings of the SunSmart Program were limited. Sun protection policy implementation was inconsistent and students were unlikely to engage in sun protection practices beyond the school setting. School communities require additional support and engagement to holistically enforce the principles of the SunSmart Program. © 2017 The Authors.

Optical model and calibration of a sun tracker

International Nuclear Information System (INIS)

Volkov, Sergei N.; Samokhvalov, Ignatii V.; Cheong, Hai Du; Kim, Dukhyeon

2016-01-01

Sun trackers are widely used to investigate scattering and absorption of solar radiation in the Earth's atmosphere. We present a method for optimization of the optical altazimuth sun tracker model with output radiation direction aligned with the axis of a stationary spectrometer. The method solves the problem of stability loss in tracker pointing at the Sun near the zenith. An optimal method for tracker calibration at the measurement site is proposed in the present work. A method of moving calibration is suggested for mobile applications in the presence of large temperature differences and errors in the alignment of the optical system of the tracker. - Highlights: • We present an optimal optical sun tracker model for atmospheric spectroscopy. • The problem of loss of stability of tracker pointing at the Sun has been solved. • We propose an optimal method for tracker calibration at a measurement site. • Test results demonstrate the efficiency of the proposed optimization methods.

Design, Fabrication and High Power RF Test of a C-band Accelerating Structure for Feasibility Study of the SPARC photo-injector energy upgrade

CERN Document Server

Alesini, D.; Di Pirro, G.; Di Raddo, R.; Ferrario, M.; Gallo, A.; Lollo, V.; Marcellini, F.; Higo, T.; Kakihara, K.; Matsumoto, S.; Campogiani, G.; Mostacci, A.; Palumbo, L.; Persichelli, S.; Spizzo, V.; Verdú-Andrés, S.

2011-01-01

The energy upgrade of the SPARC photo-injector from 160 to more than 260 MeV will be done by replacing a low gradient 3m S-Band structure with two 1.4m high gradient C-band structures. The structures are travelling wave, constant impedance sections, have symmetric waveguide input couplers and have been optimized to work with a SLED RF input pulse. A prototype with a reduced number of cells has been fabricated and tested at high power in KEK (Japan) giving very good performances in terms of breakdown rates (10^6 bpp/m) at high accelerating gradient (>50 MV/m). The paper illustrates the design criteria of the structures, the fabrication procedure and the high power RF test results.

Sun protection policies of Australian primary schools in a region of high sun exposure.

Science.gov (United States)

Harrison, S L; Garzón-Chavez, D R; Nikles, C J

2016-06-01

Queensland, Australia has the highest rates of skin cancer globally. Predetermined criteria were used to score the comprehensiveness of sun protection policies (SPP) of primary schools across Queensland. SPP were sought for schools in 10 regions (latitude range 16.3°S-28.1°S) from 2011 to 2014. Of the 723 schools sampled, 90.9% had a written SPP available publicly. Total SPP scores were low {mean 3.6 [95% CI: 3.4-3.9]; median 2 [interquartile range (IQR) 2, 4]}, with only 3.2% of schools achieving the maximum score of 12. Median SPP scores were higher in Northern and Central Queensland [both 2 (IQR 2, 6) and (IQR 2, 5), respectively] than in Southern Queensland [2 (IQR 2, 3); P = 0.004]. Clothing and hat-wearing were addressed in most policies (96% and 89%) while few schools used their SPP to plan outdoor events (5.2%) or reschedule activities to minimize sun exposure (11.7%). The SunSmart Schools program has been operating in Queensland for 17 years, and while most primary schools now have a written SPP, most are not comprehensive. Incentive-based approaches (5-star-rating award scheme and grants) may assist in addressing this issue, to reduce sun exposure of students and teachers. These data provide a baseline from which improvements in the comprehensiveness of school SPPs can be evaluated. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Linear wide angle sun sensor for spinning satellites

Science.gov (United States)

Philip, M. P.; Kalakrishnan, B.; Jain, Y. K.

1983-08-01

A concept is developed which overcomes the defects of the nonlinearity of response and limitation in range exhibited by the V-slit, N-slit, and crossed slit sun sensors normally used for sun elevation angle measurements on spinning spacecraft. Two versions of sensors based on this concept which give a linear output and have a range of nearly + or - 90 deg of elevation angle are examined. Results are presented for the application of the twin slit version of the sun sensor in the three Indian satellites, Rohini, Apple, and Bhaskara II, which was successfully used for spin rate control and spin axis orientation control corrections as well as for sun elevation angle and spin period measurements.

VUV Spectroscopy of the Sun as a Star

Science.gov (United States)

Kankelborg, Charles; Philip, Judge; Winebarger, Amy R.; Kobayashi, Ken; Smart, Roy

2017-08-01

We describe a new sounding rocket mission to obtain the first high resolution, high quality VUV (100-200 nm) spectrum of the Sun-as-a-star. Our immediate science goal is to understand better the processes of chromospheric and coronal heating. HST data exist for a dozen or so Sun-like stars of a quality already beyond our ability to construct a comparable sun-as-a-star UV spectrum. The solar spectrum we obtain will enable us to understand the nature of magnetic energy dissipation as a Sun-like star evolves, and the dependence of magnetic activity on stellar mass and metallicity. This poster presents the instrument design, scientific prospects, and broader impacts of the proposed mission.

Intelligent Sun Tracking for a CPV Power Plant

International Nuclear Information System (INIS)

Maqsood, Ishtiaq; Emziane, Mahieddine

2010-01-01

The output of a solar panel is strongly dependent on the amount of perpendicular light flux falling on its surface, and a tracking system tries to parallel the vector area of the solar panel surface to the incident solar flux. We present a tracking technique based on a two-axis sun sensor which can be used to increase the power output from a number of CPV arrays connected together in a solar power plant. The outdoor testing procedure of the developed two-axis sun sensor is discussed. The detail of the algorithm used together with the related sun tracking equipment is also presented and discussed for the new two axes sun tracking system.

Space Medicine: Shuttle - Space Station Crew Health and Safety Challenges for Exploration

Science.gov (United States)

Dervay, Joseph

2010-01-01

This slide presentation combines some views of the shuttle take off, and the shuttle and space station on orbit, and some views of the underwater astronaut training , with a general discussion of Space Medicine. It begins with a discussion of the some of the physiological issues of space flight. These include: Space Motion Sickness (SMS), Cardiovascular, Neurovestibular, Musculoskeletal, and Behavioral/Psycho-social. There is also discussion of the space environment and the issues that are posed including: Radiation, Toxic products and propellants, Habitability, Atmosphere, and Medical events. Included also is a discussion of the systems and crew training. There are also artists views of the Constellation vehicles, the planned lunar base, and extended lunar settlement. There are also slides showing the size of earth in perspective to the other planets, and the sun and the sun in perspective to other stars. There is also a discussion of the in-flight changes that occur in neural feedback that produces postural imbalance and loss of coordination after return.

Predictors of sun protection behaviours and sunburn among Australian adolescents.

Science.gov (United States)

Pettigrew, Simone; Jongenelis, Michelle; Strickland, Mark; Minto, Carolyn; Slevin, Terry; Jalleh, Geoffrey; Lin, Chad

2016-07-13

Excessive sun exposure and sunburn increase individuals' risk of skin cancer. It is especially important to prevent sunburn in childhood due to the higher relative risk of skin cancer across the life span compared to risk associated with sunburn episodes experienced later in life. This study examined demographic and attitudinal factors associated with engagement in a range of sun protection behaviours (wearing a hat, wearing protective clothing, staying in the shade, and staying indoors during the middle of the day) and the frequency of sunburn among Western Australian adolescents to provide insights of relevance for future sun protection campaigns. Cross-sectional telephone surveys were conducted annually with Western Australians between 2005/06 and 2014/15. The results from 4150 adolescents aged 14-17 years were used to conduct a path analysis of factors predicting various sun protection behaviours and sunburn. Significant primary predictors of the sun protection behaviours included in the study were skin type (sun sensitivity), gender, tanning-related attitudes and behaviours, and perceived relevance of public service advertisements that advocate sun protection. Of the four sun protection behaviours investigated, staying in the shade and staying indoors during the middle of the day were associated with a lower frequency of sunburn. There is a particular need to target sun protection messages at adolescent males who are less likely to engage in the most effective sun protection behaviours and demonstrate an increased propensity to experience sunburn. The results suggest that such future sun protection messages should include a focus on the importance of staying in the shade or indoors during periods of high UV radiation to increase awareness of the efficacy of these methods of avoiding skin cancer.

Prediction of Communication Outage Period between Satellite and Earth station Due to Sun Interference

Directory of Open Access Journals (Sweden)

Yongjun Song

2010-03-01

Full Text Available We developed a computer program to predict solar interference period. To calculate Sun‘s position, we used DE406 ephemerides and Earth ellipsoid model. The Sun‘s position error is smaller than 10arcsec. For the verification of the calculation, we used TU media ground station on Seongsu-dong, and MBSAT geostationary communication satellite. We analysis errors, due to satellite perturbation and antenna align. The time error due to antenna align has -35 to +16 seconds at 0.1 degree, and -27 to +41 seconds at 0.25 degree. The time errors derived by satellite perturbation has 30 to 60 seconds.

‘My child did not like using sun protection’: practices and perceptions of child sun protection among rural black African mothers

OpenAIRE

Zamantimande Kunene; Patricia N. Albers; Robyn M. Lucas; Cathy Banwell; Angela Mathee; Caradee Y. Wright

2017-01-01

Abstract Background Photodamage is partially mitigated by darker skin pigmentation, but immune suppression, photoaging and cataracts occur among individuals with all skin types. Methods To assess practices and acceptability to Black African mothers of sun protection equipment for their children living in a rural area, participants were recruited at the time of their child’s 18-month vaccinations. Mothers completed a baseline questionnaire on usual sun behaviours and sun protection practices. ...

The Sun murrab Baltimaadesse ja Soome

Index Scriptorium Estoniae

2008-01-01

Aprillis andis ansambel Tanel Padar & The Sun Soomes, Lätis, Leedus ja Eestis üksteist kontserti. Heliplaadi "Here Gomes The Sun" lugu "Hopelessness You" on Soome raadiote tipp 300s neljakümnendal kohal, lugu "Learn the game" on Leedu FM99 raadios 33 enim mängitava loo seas, laul "One of those days" saavutas Läti raadio SWH rokkmuusika edetabelis teise koha.

The evolution of low-mass close binary systems. IV. 0.80 M/sub sun/+0.40 M/sub sun/: Catastrophic mass loss

International Nuclear Information System (INIS)

Webbink, R.F.

1977-01-01

The evolution of both components of a 0.80 M/sub sun/+0.40 M/sub sun/ binary with initial separation 1.60 R/sub sun/ is presented. This system reaches mass transfer during core hydrogen burning in the primary. The primary has such a deep convective envelope that mass transfer proceeds on a dynamical time scale. Mass exchange is followed through the first 6.25 x 10 -3 M/sub sun/, by which time the transfer rate has reached 8.33 x 10 -4 M/sub sun/ yr -1 .It is shown that mass transfer on a dynamical time scale leads to supercritical accretion by the secondary component, and hence is presumably accompanied by extensive mass and angular momentum losses. Stability against such rapid mass transfer may impose severe limitations on the masses and mass ratios of cataclysmic variables

SunShot Initiative Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

DOE Solar Energy Technologies Office

2015-04-01

The U.S. Department of Energy (DOE) SunShot Initiative is a collaborative national effort launched in 2011 that aggressively drives innovation to make solar energy fully cost competitive with traditional energy sources before the end of the decade. The SunShot fact sheet outlines goals and successes of the program as it works with private companies, universities, non-profit organizations, state and local governments, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour, without incentives, by the year 2020.

An Inexpensive High-Temporal Resolution Electronic Sun Journal for Monitoring Personal Day to Day Sun Exposure Patterns

Directory of Open Access Journals (Sweden)

Nathan J. Downs

2017-11-01

Full Text Available Exposure to natural sunlight, specifically solar ultraviolet (UV radiation contributes to lifetime risks of skin cancer, eye disease, and diseases associated with vitamin D insufficiency. Improved knowledge of personal sun exposure patterns can inform public health policy; and help target high-risk population groups. Subsequently, an extensive number of studies have been conducted to measure personal solar UV exposure in a variety of settings. Many of these studies, however, use digital or paper-based journals (self-reported volunteer recall, or employ cost prohibitive electronic UV dosimeters (that limit the size of sample populations, to estimate periods of exposure. A cost effective personal electronic sun journal (ESJ built from readily available infrared photodiodes is presented in this research. The ESJ can be used to complement traditional UV dosimeters that measure total biologically effective exposure by providing a time-stamped sun exposure record. The ESJ can be easily attached to clothing and data logged to personal devices (including fitness monitors or smartphones. The ESJ improves upon self-reported exposure recording and is a cost effective high-temporal resolution option for monitoring personal sun exposure behavior in large population studies.

Convective penetration in a young sun

Science.gov (United States)

Pratt, Jane; Baraffe, Isabelle; Goffrey, Tom; MUSIC developers group

2018-01-01

To interpret the high-quality data produced from recent space-missions it is necessary to study convection under realistic stellar conditions. We describe the multi-dimensional, time implicit, fully compressible, hydrodynamic, implicit large eddy simulation code MUSIC. We use MUSIC to study convection during an early stage in the evolution of our sun where the convection zone covers approximately half of the solar radius. This model of the young sun possesses a realistic stratification in density, temperature, and luminosity. We approach convection in a stellar context using extreme value theory and derive a new model for convective penetration, targeted for one-dimensional stellar evolution calculations. This model provides a scenario that can explain the observed lithium abundance in the sun and in solar-like stars at a range of ages.

Pre-main sequence sun: a dynamic approach

International Nuclear Information System (INIS)

Newman, M.J.; Winkler, K.H.A.

1979-01-01

The classical pre-main sequence evolutionary behavior found by Hayashi and his coworkers for the Sun depends crucially on the choice of initial conditions. The Hayashi picture results from beginning the calculation with an already centrally condensed, highly Jeans unstable object not terribly far removed from the stellar state initially. The present calculation follows the work of Larson in investigating the hydrodynamic collapse and self-gravitational accretion of an initially uniform, just Jeans unstable interstellar gas-dust cloud. The resulting picture for the early history of the Sun is quite different from that found by Hayashi. A rather small (R approx. = 2 R/sub sun/), low-luminosity (L greater than or equal to L/sub sun/) protostellar core develops. A fully convective stellar core, characteristic of Hayashi's work, is not found during the accretion process, and can only develop, if at all, in the subsequent pre-main sequence Kelvin-Helmholtz contraction of the core. 3 figures, 1 table

Unintended Sunburn: A Potential Target for Sun Protection Messages

Directory of Open Access Journals (Sweden)

Geraldine F. H. McLeod

2017-01-01

Full Text Available New Zealand (NZ has the highest melanoma incidence rate in the world. Primary prevention efforts focus on reducing sunburn incidence and increasing sun protective practices in the population. However, sunburn from excessive ultraviolet radiation (UVR remains common. To reduce sunburn incidence, it is important to examine those individuals who experience unintended sunburn. This study aims to use data from the NZ Triennial Sun Protection Survey to describe respondents who were not intending to tan but were sunburnt after outdoor UVR exposure. Information on sociodemographics, concurrent weather conditions, sun protection attitudes and knowledge, and outdoor behaviour was also collected. The results showed 13.5% of respondents’ experienced unintended sunburn during the survey weekend but had not attempted to obtain a tan that summer. Respondents who reported unintended sunburn were more likely than others to have been near water and in unshaded areas, used sunscreen, had higher SunSmart knowledge scores, had lower positive attitudes towards tanning, and were outdoors for a longer duration with less body coverage. As sunburn was unintended these respondents’ outdoor sun protective behaviours may be amenable to change. Future public health initiatives should focus on increasing sun protection (clothing and shade and reducing potential barriers to sun protection.

Unintended Sunburn: A Potential Target for Sun Protection Messages.

Science.gov (United States)

McLeod, Geraldine F H; Reeder, Anthony I; Gray, Andrew R; McGee, Rob

2017-01-01

New Zealand (NZ) has the highest melanoma incidence rate in the world. Primary prevention efforts focus on reducing sunburn incidence and increasing sun protective practices in the population. However, sunburn from excessive ultraviolet radiation (UVR) remains common. To reduce sunburn incidence, it is important to examine those individuals who experience unintended sunburn. This study aims to use data from the NZ Triennial Sun Protection Survey to describe respondents who were not intending to tan but were sunburnt after outdoor UVR exposure. Information on sociodemographics, concurrent weather conditions, sun protection attitudes and knowledge, and outdoor behaviour was also collected. The results showed 13.5% of respondents' experienced unintended sunburn during the survey weekend but had not attempted to obtain a tan that summer. Respondents who reported unintended sunburn were more likely than others to have been near water and in unshaded areas, used sunscreen, had higher SunSmart knowledge scores, had lower positive attitudes towards tanning, and were outdoors for a longer duration with less body coverage. As sunburn was unintended these respondents' outdoor sun protective behaviours may be amenable to change. Future public health initiatives should focus on increasing sun protection (clothing and shade) and reducing potential barriers to sun protection.

Sun-Earth Day - Teaching Heliophysics Through Education Technology

Science.gov (United States)

Thieman, J.; Cline, T.; Lewis, E.

2010-01-01

Sun-Earth Day (SED) is an Education and Outreach program supported by the U.S, National Aeronautics and Space Administration (NASA). The intent of the program is to teach students and the general public about Heliophysics (the science of the study of the Sun, how it varies, and how solar dynamics affect the rest of the solar system, especially the Earth). The program was begun ten years ago. Each year since that time a particular day has been designated as "Sun-Earth Day ,,. Usually the day of the spring equinox (March 20 or 21) is Sun-Earth Day, but other days have been used as well. Each year a theme is chosen relating to Heliophysics and events reflecting that theme are planned not only for Sun-Earth Day, but for the entire year. From the very beginning educational technology was emphasized in the events in order to effectively reach wide audiences with the SED message. The main approach has been to have a "webcast" related to each year's theme, often from a location that supports the theme as well. For example, a webcast took place from the Mayan pyramids at Chichen Itza, Mexico to highlight the theme of "Ancient Observatories, Timeless Knowledge". Webcasts were not the only technology employed, however. Many of the themes centered on the dynamic nature of the Sun and the effects that solar storms can have on interplanetary space and in our day-to-day life on Earth. Activities for tracking when solar storms happen and how they affect the Earth were developed and brought together in an educational package called Space Weather Action Centers. This project is explained in more detail in another presentation in this session being given by Norma Teresinha Oliveira Reis. Recent Sun-Earth Days have utilized "social networking" technologies to reach widespread groups on the internet. Podcasts, Vodcasts, Facebook, Twitter, and Second Life are the types of network technologies being employed now. The NASA Distance learning Network is another method for bringing Sun

Predictors of sun protection behaviours and sunburn among Australian adolescents

Directory of Open Access Journals (Sweden)

Simone Pettigrew

2016-07-01

Full Text Available Abstract Background Excessive sun exposure and sunburn increase individuals’ risk of skin cancer. It is especially important to prevent sunburn in childhood due to the higher relative risk of skin cancer across the life span compared to risk associated with sunburn episodes experienced later in life. This study examined demographic and attitudinal factors associated with engagement in a range of sun protection behaviours (wearing a hat, wearing protective clothing, staying in the shade, and staying indoors during the middle of the day and the frequency of sunburn among Western Australian adolescents to provide insights of relevance for future sun protection campaigns. Methods Cross-sectional telephone surveys were conducted annually with Western Australians between 2005/06 and 2014/15. The results from 4150 adolescents aged 14–17 years were used to conduct a path analysis of factors predicting various sun protection behaviours and sunburn. Results Significant primary predictors of the sun protection behaviours included in the study were skin type (sun sensitivity, gender, tanning-related attitudes and behaviours, and perceived relevance of public service advertisements that advocate sun protection. Of the four sun protection behaviours investigated, staying in the shade and staying indoors during the middle of the day were associated with a lower frequency of sunburn. Conclusion There is a particular need to target sun protection messages at adolescent males who are less likely to engage in the most effective sun protection behaviours and demonstrate an increased propensity to experience sunburn. The results suggest that such future sun protection messages should include a focus on the importance of staying in the shade or indoors during periods of high UV radiation to increase awareness of the efficacy of these methods of avoiding skin cancer.

The Toboggan Sun

NARCIS (Netherlands)

Davidson, WPS; van der Werf, SY

2005-01-01

Special variants of the Novaya Zemlya effect may arise from localized temperature inversions that follow the height profile of hills or mountains. Rather than following its natural path, the rising or setting Sun may, under such circumstances, appear to slide along a distant mountain slope. We found

YUAN-BO SUN

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. YUAN-BO SUN. Articles written in Journal of Genetics. Volume 97 Issue 1 March 2018 pp 173-178 RESEARCH ARTICLE. Investigating multiple dysregulated pathways in rheumatoid arthritis based on pathway interaction network · XIAN-DONG SONG XIAN-XU SONG GUI-BO LIU ...

Sun protection among Spanish beachgoers: knowledge, attitude and behaviour.

Science.gov (United States)

Cercato, M C; Ramazzotti, V; Sperduti, I; Asensio-Pascual, A; Ribes, I; Guillén, C; Nagore, E

2015-03-01

This study aims to investigate the level of awareness on the risks related to sun exposure, attitude towards sun protection and sun protection behaviour in Spanish beachgoers. During the summer of 2009, trained assistants conducted a structured interview with 630 sunbathers at the beaches of Valencia, Spain, via administrating a questionnaire including the following: (a) general data (age, gender, education, profession), (b) "knowledge" and "attitude" items and (c) self-assessed sun sensitivity, sun exposure and sun protection characteristics. The health belief model was used to evaluate factors that may influence on engaging healthy behaviour. The median age was 30 (2-82) years; the M/F ratio was 0.60. Despite the widespread regular ("often" or "always", 80%) use of high (>15) sun-protective factor sunscreens, current recommendations on sun protection were not regularly followed, and a history of sunburns is very common (70%). At multivariate analysis, female gender, age, fair hair, freckles, all-day use of sunscreens and wearing sunglasses were independent factors associated with having sunburn history. A high knowledge and a fairly good attitude emerged (median scores, 6/7 and 22/30, respectively). Age class (p = 0.032), educational level (p < 0.0001), sunscreen use (p = 0.048) and adequate timing of the first application of sunscreens (p = 0.015) were predictors of awareness, while factors associated with a more favourable attitude were educational level (p < 0.0001) and regular use of hats (p = 0.001). Wrong beliefs mainly concern sunscreens (false safety); the attractiveness of a tanned look is the main unfavourable attitude. Physical and motivational barriers are common (80%). The findings by highlighting constitutional and psychosocial factors involved in unhealthy behaviour provide useful information to promote sun-safe interventions in this population.

The Sun A User's Manual

CERN Document Server

Vita-Finzi, Claudio

2008-01-01

The Sun is an account of the many ways in which our nearest star affects our planet, how its influence has changed over the last few centuries and millennia, and the extent to which we can predict its future impact. The Sun's rays foster the formation of Vitamin D by our bodies, but it can also promote skin cancer, cataracts, and mutations in our DNA. Besides providing the warmth and light essential to most animal and plant life, solar energy contributes substantially to global warming. Although the charged particles of the solar wind shield us from harmful cosmic rays, solar storms may damage artificial satellites and cripple communication systems and computer networks. The Sun is the ideal renewable energy source, but its exploitation is still bedevilled by the problems of storage and distribution. Our nearest star, in short, is a complex machine which needs to be treated with caution, and this book will equip every reader with the knowledge that is required to understand the benefits and dangers it can bri...

Ra: The Sun for Science and Humanity

Science.gov (United States)

1996-01-01

To guide the development of the Ra Strategic Framework, we defined scientific and applications objectives. For our primary areas of scientific interest, we choose the corona, the solar wind, the Sun's effect on the Earth, and solar theory and model development. For secondary areas of scientific interest, we selected sunspots, the solar constant, the Sun's gravitational field, helioseismology and the galactic cosmic rays. We stress the importance of stereoscopic imaging, observations at high spatial, spectral, and temporal resolutions, as well as of long duration measurements. Further exploration of the Sun's polar regions is also important, as shown already by the Ulysses mission. From an applications perspective, we adopted three broad objectives that would derive complementary inputs for the Strategic Framework. These were to identify and investigate: possible application spin-offs from science missions, possible solar-terrestrial missions dedicated to a particular application, and possible future applications that require technology development. The Sun can be viewed as both a source of resources and of threats. Our principal applications focus was that of threat mitigation, by examining ways to improve solar threat monitoring and early warning systems. We compared these objectives to the mission objectives of past, current, and planned international solar missions. Past missions (1962-1980) seem to have been focused on improvement of scientific knowledge, using multiple instrument spacecraft. A ten year gap followed this period, during which the results from previous missions were analyzed and solar study programmes were prepared in international organizations. Current missions (1990-1996) focus on particular topics such as the corona, solar flares, and coronal mass ejections. In planned missions, Sun/Earth interactions and environmental effects of solar activity are becoming more important. The corona is the centre of interest of almost all planned missions

Invariant Solar Sail Formations in Elliptical Sun-Synchronous Orbits

Science.gov (United States)

Parsay, Khashayar

Current and past missions that study the Earth's geomagnetic tail require multiple spacecraft to fly in formation about a highly eccentric Keplerian reference orbit that has its apogee inside a predefined science region of interest. Because the geomagnetic tail is directed along the Sun-Earth line and therefore rotates annually, inertially fixed Keplerian orbits are only aligned with the geomagnetic tail once per year. This limitation reduces the duration of the science phase to less than a few months annually. Solar sails are capable of creating non-Keplerian, Sun-synchronous orbits that rotate with the geomagnetic tail. A solar sail flying in a Sun-synchronous orbit will have a continuous presence in the geomagnetic tail throughout the entire year, which significantly improves the in situ observations of the magnetosphere. To achieve a Sun-synchronous orbit, a solar sail is required to maintain a Sun-pointing attitude, which leads to the artificial precession of the orbit apse line in a Sun-synchronous manner, leaving the orbit apogee inside the science region of interest throughout entire the year. To study the spatial and temporal variations of plasma in the highly dynamic environment of the magnetosphere, multiple spacecraft must fly in a formation. The objective for this dissertation is to investigate the feasibility of solar sail formation flying in the Earth-centered, Sun-synchronous orbit regime. The focus of this effort is to enable formation flying for a group of solar sails that maintain a nominally fixed Sun-pointing attitude during formation flight, solely for the purpose of precessing their orbit apse lines Sun-synchronously. A fixed-attitude solar sail formation is motivated by the difficulties in the simultaneous control of orbit and attitude in flying solar sails. First, the secular rates of the orbital elements resulting from the effects of solar radiation pressure (SRP) are determined using averaging theory for a Sun-pointing attitude sail

The electron-dose distribution surrounding an 192Ir wire bracytherapy source investigated using EGS4 simulations and GafChromic film

International Nuclear Information System (INIS)

Cheung, Y.C.; Yu, P.K.N.; Young, E.C.M.; Wong, T.P.Y.

1997-01-01

The steep dose gradient around 192 Ir brachytherapy wire implants is predicted by the EGS4 (PRESTA version) Monte Carlo simulation. When considering radiation absorbing regions close to the wire source, the accurate dose distribution cannot be calculated by the GE Target II Sun Sparc treatment-planning system. Experiments using GafChromic TM film have been performed to prove the validity of the EGS4 user code when calculating the dose close to the wire source in a low energy range. (Author)

Using CNLS-net [Connectionist Normalized Local Spline-network] to predict the Mackey-Glass chaotic time series

International Nuclear Information System (INIS)

Mead, W.C.; Jones, R.D.; Barnes, C.W.; Lee, L.A.; O'Rourke, M.K.; Lee, Y.C.; Flake, G.W.

1991-01-01

We use the Connectionist Normalized Local Spline (CNLS) network to learn the dynamics of the Mackey-Glass time-delay differential equation, for the case τ = 30. We show the optimum network operating mode and determine the accuracy and robustness of predictions. We obtain pedictions of varying accuracy using some 2--120 minutes of execution time on a Sun SPARC-1 workstation. CNLS-net is capable of very good performance in predicting the Mackey-Glass time series. 11 refs., 4 figs

A Portable Parallel Implementation of the U.S. Navy Layered Ocean Model

Science.gov (United States)

1995-01-01

Wallcraft, PhD (I.C. 1981) Planning Systems Inc. & P. R. Moore, PhD (Camb. 1971) IC Dept. Math. DR Moore 1° Encontro de Metodos Numericos...Kendall Square, Hypercube, D R Moore 1 ° Encontro de Metodos Numericos para Equacöes de Derivadas Parciais A. J. Wallcraft IC Mathematics...chips: Chips Machine DEC Alpha CrayT3D/E SUN Sparc Fujitsu AP1000 Intel 860 Paragon D R Moore 1° Encontro de Metodos Numericos para Equacöes

Structure and expression of the maize (Zea mays L. SUN-domain protein gene family: evidence for the existence of two divergent classes of SUN proteins in plants

Directory of Open Access Journals (Sweden)

Simmons Carl R

2010-12-01

Full Text Available Abstract Background The nuclear envelope that separates the contents of the nucleus from the cytoplasm provides a surface for chromatin attachment and organization of the cortical nucleoplasm. Proteins associated with it have been well characterized in many eukaryotes but not in plants. SUN (Sad1p/Unc-84 domain proteins reside in the inner nuclear membrane and function with other proteins to form a physical link between the nucleoskeleton and the cytoskeleton. These bridges transfer forces across the nuclear envelope and are increasingly recognized to play roles in nuclear positioning, nuclear migration, cell cycle-dependent breakdown and reformation of the nuclear envelope, telomere-led nuclear reorganization during meiosis, and karyogamy. Results We found and characterized a family of maize SUN-domain proteins, starting with a screen of maize genomic sequence data. We characterized five different maize ZmSUN genes (ZmSUN1-5, which fell into two classes (probably of ancient origin, as they are also found in other monocots, eudicots, and even mosses. The first (ZmSUN1, 2, here designated canonical C-terminal SUN-domain (CCSD, includes structural homologs of the animal and fungal SUN-domain protein genes. The second (ZmSUN3, 4, 5, here designated plant-prevalent mid-SUN 3 transmembrane (PM3, includes a novel but conserved structural variant SUN-domain protein gene class. Mircroarray-based expression analyses revealed an intriguing pollen-preferred expression for ZmSUN5 mRNA but low-level expression (50-200 parts per ten million in multiple tissues for all the others. Cloning and characterization of a full-length cDNA for a PM3-type maize gene, ZmSUN4, is described. Peptide antibodies to ZmSUN3, 4 were used in western-blot and cell-staining assays to show that they are expressed and show concentrated staining at the nuclear periphery. Conclusions The maize genome encodes and expresses at least five different SUN-domain proteins, of which the PM3

The Sun was Not Born in M67

Science.gov (United States)

Pichardo, Bárbara; Moreno, Edmundo; Allen, Christine; Bedin, Luigi R.; Bellini, Andrea; Pasquini, Luca

2012-03-01

Using the most recent proper-motion determination of the old, solar-metallicity, Galactic open cluster M67 in orbital computations in a non-axisymmetric model of the Milky Way, including a bar and three-dimensional spiral arms, we explore the possibility that the Sun once belonged to this cluster. We have performed Monte Carlo numerical simulations to generate the present-day orbital conditions of the Sun and M67, and all the parameters in the Galactic model. We compute 3.5 × 105 pairs of orbits Sun-M67 looking for close encounters in the past with a minimum distance approach within the tidal radius of M67. In these encounters we find that the relative velocity between the Sun and M67 is larger than 20 km s-1. If the Sun had been ejected from M67 with this high velocity by means of a three-body encounter, this interaction would have either destroyed an initial circumstellar disk around the Sun or dispersed its already formed planets. We also find a very low probability, much lower than 10-7, that the Sun was ejected from M67 by an encounter of this cluster with a giant molecular cloud. This study also excludes the possibility that the Sun and M67 were born in the same molecular cloud. Our dynamical results convincingly demonstrate that M67 could not have been the birth cluster of our solar system. This work relies partly on observations of the Large Binocular Telescope (LBT). The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are The Ohio State University; The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.

Parental use of sun protection for their children-does skin color matter?

Science.gov (United States)

Tan, Marcus G; Nag, Shudeshna; Weinstein, Miriam

2018-03-01

Excessive sun exposure during childhood is a risk factor for skin cancer. This study aimed to compare the frequency of ideal sun protection use between parents with lighter- and darker-skinned children and explore their attitudes and beliefs on sun safety and their choice of sun protection. Parents of children aged 6 months to 6 years completed self-administered questionnaires about sun protection practices for their children. Parents assessed their child's Fitzpatrick phototype and were divided into lighter- (Fitzpatrick phototype I-III) and darker-skinned (Fitzpatrick phototype IV-VI) groups. Sun safety guidelines from the Canadian Dermatology Association were used to qualify ideal sun protection. A total of 183 parents were included. Overall, 31 parents (17%) used ideal sun protection for their children. As their children grew older, parents were less likely to use ideal sun protection (odds ratio = 0.69, 95% confidence interval = 0.53-0.90). Parents in the lighter-skinned group were more likely to use ideal sun protection for their children (odds ratio = 7.4, 95% confidence interval = 2.7-20.1), believe that sun exposure was harmful (odds ratio = 17.2, 95% confidence interval = 4.0-74.9), and perceive value in sun protection (odds ratio = 11.4, 95% confidence interval = 3.3-39.0); the darker-skinned group believed that darker skin tones provided more sun protection (odds ratio = 12.4, 95% confidence interval = 6.1-25.4). Ideal parental sun protection efforts are overall low, particularly in parents of darker-skinned children. The identified attitudes toward and beliefs about sun safety may aid in delivery of future sun protection interventions, especially in multiracial populations. © 2018 Wiley Periodicals, Inc.

Sun-view angle effects on reflectance factors of corn canopies

Science.gov (United States)

Ranson, K. J.; Daughtry, C. S. T.; Biehl, L. L.; Bauer, M. E.

1985-01-01

The effects of sun and view angles on reflectance factors of corn (Zea mays L.) canopies ranging from the six leaf stage to harvest maturity were studied on the Purdue University Agronomy Farm by a multiband radiometer. The two methods of acquiring spectral data, the truck system and the tower systrem, are described. The analysis of the spectral data is presented in three parts: solar angle effects on reflectance factors viewed at nadir; solar angle effects on reflectance factors viewed at a fixed sun angle; and both sun and view angles effect on reflectance factors. The analysis revealed that for nadir-viewed reflectance factors there is a strong solar angle dependence in all spectral bands for canopies with low leaf area index. Reflectance factors observed from the sun angle at different view azimuth angles showed that the position of the sensor relative to the sun is important in determining angular reflectance characteristics. For both sun and view angles, reflectance factors are maximized when the sensor view direction is towards the sun.

Sun and Sjogren's Syndrome

Science.gov (United States)

Patient Education Sheet The Sun and Sjögren’s Syndrome The SSF thanks Mona Z. Mofid, MD, FAAD, Diplomate, American Board of Dermatology, and Medical Director, American Melanoma Foundation, San Diego, California, ...

Licensing the Sun

Science.gov (United States)

Demski, Jennifer

2013-01-01

The University of San Diego (USD) and Point Loma Nazarene University (PLNU) are licensing the sun. Both California schools are generating solar power on campus without having to sink large amounts of capital into equipment and installation. By negotiating power purchasing agreements (PPAs) with Amsolar and Perpetual Energy Systems, respectively,…

The Sun as a system of elementary particles

International Nuclear Information System (INIS)

Kleczek, J.

1986-01-01

The paper based on known facts of solar physics-is an attempt to interpret the Sun as a selfgravitating system of about 10/sup 57/ nucleons and electrons. These elementary particles are endowed with strong, electromagnetic, weak and gravitational interactions. Origin of the Sun, its evolution, structure and physiology are consequences of the four interactions. Each structural property, every evolutionary process, any activity phenomenon or event on the Sun can be traced backwards to the four fundamental forces of nature, viz. to interactions of elementary particles

Space Station view of the Pyramids at Giza

Science.gov (United States)

2002-01-01

One of the world's most famous archaeological sites has been photographed in amazing detail by the astronauts onboard Space Station Alpha. This image, taken 15 August, 2001, represents the greatest detail of the Giza plateau captured from a human-occupied spacecraft (approximate 7 m resolution). Afternoon sun casts shadows that help the eye make out the large pyramids of Khufu, Khafre and Menkaure. Sets of three smaller queens' pyramids can be seen to the east of the Pyramid of Khufu and south of the Pyramid of Menkaure. The light-colored causeway stretching from the Mortuary Temple at the Pyramid of Khafre to the Valley Temple near the Sphinx (arrow) can also be seen. Because it is not tall enough to cast a deep shadow, the Sphinx itself cannot readily be distinguished. Although some commercial satellites, such as IKONOS, have imaged the Pyramids at Giza in greater detail (1 m resolution), this image highlights the potential of the International Space Station as a remote sensing platform. A commercial digital camera without space modifications was used to obtain this picture. Similarly, a variety of remote sensing instruments developed for use on aircraft can potentially be used from the Space Station. Currently, all photographs of Earth taken by astronauts from the Space Shuttle and Space Station are released to the public for scientific and educational benefit and can be accessed on the World Wide Web through the NASA-JSC Gateway to Astronaut Photography of Earth (http://eol/jsc.nasa.gov/sseop). Image ISS003-ESC-5120 was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center (http://eol.jsc.nasa.gov).

Thermal comfort in sun spaces: To what extend can energy collectors and seasonal energy storages provide thermal comfort in sun space?

Directory of Open Access Journals (Sweden)

Christian Wiegel

2017-10-01

Full Text Available Preparation for fossil fuel substitution in the building sector persists as an essential subject in architectural engineering. Since the building sector still remains as one of the three major global end energy consumer – climate change is closely related to construction and design. We have developed the archetype sun space to what it is today : a simple but effective predominant naturally ventilated sun trap and as well as living space enlargement. With the invention of industrial glass orangery’s more and more changed from frost protecting envelopes to living spaces from which we meantime expect thermal comfort in high quality. But what level of thermal comfort provide sun spaces? And to what extend may sun spaces manage autarkic operation profiting from passive solar gains and, beyond that, surplus energy generation for energy neutral conditioning of aligned spaces? We deliver detailed information for this detected gap of knowledge. We know about limited thermal comfort in sun spaces winter times. This reasons the inspection of manifold collector technologies, which enable to be embedded in facades and specifically in sun space envelopes. Nonetheless, effective façade integrated collectors are ineffective in seasons with poor irradiation. Hence, the mismatch of offer and demand we have experienced with renewable energies ignites thinking about appropriate seasonal energy storages, which enlarges the research scope of this work. This PhD thesis project investigates on both, a yearly empirical test set up analysis and a virtual simulation of different oriented and located sun spaces abroad Germany. Both empirical and theoretical evaluation result in a holistic research focusing on a preferred occupation time in terms of cumulative frequencies of operational temperature and decided local discomfort, of potential autarkic sun space operation and prospective surplus exergy for alternative heating of aligned buildings. The results are mapped

Night glow of the Earth ionosphere according to observations at the Salyut 6 orbital station

International Nuclear Information System (INIS)

Ryumin, V.V.; Nesmyanovich, I.A.; Nikol'skij, G.M.; Popov, L.I.; Savchenko, S.A.

1983-01-01

Results of photometric processing of coloured reversible photos of the nocturnal ionosphere obtained from the board of orbital station ''Salyut-6'' in 1980 are presented. Connections of emission airglow of the first layer (E region) and the second layer (F region) with the Sun submerging below the horizon and with geomagnetic latitude are analyzed. The colour and intensity of the first layer and the intensity of the second layer considerably change depending on the time and place of observations. A 2 times increase in the intensity of the first layer before the Sunrise and its certain ''reddening'' with the Sun maximum submerging is noted. The intensity of the second layer increases sharply (up to 10 times) with the Sun submergence. The upper limit of the ratio between green emission in the line lambda=557.7 nm and red emission in the line lambda=630.0 nm is 0.25 for the second layer. The dependence of the airglow intensity of the second layer on the geomagnetic latitude points to the presence of tropic zones of the airglow intensification on both sides of the equator

Outdoor Workers' Use of Sun Protection at Work and Leisure

Directory of Open Access Journals (Sweden)

Cheryl E. Peters

2016-09-01

Conclusion: This high-participation rate cohort helps characterize sun protection behaviors among outdoor workers. Workers practiced better sun protection at work than on weekends, suggesting that workplace policies supportive of sun protection could be useful for skin cancer prevention in the construction industry.

Developing a multipurpose sun tracking system using fuzzy control

Energy Technology Data Exchange (ETDEWEB)

Alata, Mohanad [Department of Mechanical Engineering, Jordan University of Science and Technology (JUST), PO Box 3030, Irbid 22110 (Jordan)]. E-mail: alata@just.edu.jo; Al-Nimr, M.A. [Department of Mechanical Engineering, Jordan University of Science and Technology (JUST), PO Box 3030, Irbid 22110 (Jordan); Qaroush, Yousef [Department of Mechanical Engineering, Jordan University of Science and Technology (JUST), PO Box 3030, Irbid 22110 (Jordan)

2005-05-01

The present work demonstrates the design and simulation of time controlled step sun tracking systems that include: one axis sun tracking with the tilted aperture equal to the latitude angle, equatorial two axis sun tracking and azimuth/elevation sun tracking. The first order Sugeno fuzzy inference system is utilized for modeling and controller design. In addition, an estimation of the insolation incident on a two axis sun tracking system is determined by fuzzy IF-THEN rules. The approach starts by generating the input/output data. Then, the subtractive clustering algorithm, along with least square estimation (LSE), generates the fuzzy rules that describe the relationship between the input/output data of solar angles that change with time. The fuzzy rules are tuned by an adaptive neuro-fuzzy inference system (ANFIS). Finally, an open loop control system is designed for each of the previous types of sun tracking systems. The results are shown using simulation and virtual reality. The site of application is chosen at Amman, Jordan (32 deg. North, 36 deg. East), and the period of controlling and simulating each type of tracking system is the year 2003.

Thermal remote sensing from Airborne Hyperspectral Scanner data in the framework of the SPARC and SEN2FLEX projects: an overview

Directory of Open Access Journals (Sweden)

Q. Shen

2009-11-01

Full Text Available The AHS (Airborne Hyperspectral Scanner instrument has 80 spectral bands covering the visible and near infrared (VNIR, short wave infrared (SWIR, mid infrared (MIR and thermal infrared (TIR spectral range. The instrument is operated by Instituto Nacional de Técnica Aerospacial (INTA, and it has been involved in several field campaigns since 2004.

This paper presents an overview of the work performed with the AHS thermal imagery provided in the framework of the SPARC and SEN2FLEX campaigns, carried out respectively in 2004 and 2005 over an agricultural area in Spain. The data collected in both campaigns allowed for the first time the development and testing of algorithms for land surface temperature and emissivity retrieval as well as the estimation of evapotranspiration from AHS data. Errors were found to be around 1.5 K for land surface temperature and 1 mm/day for evapotranspiration.

Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

International Nuclear Information System (INIS)

Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R.; Brönnimann, M.; Cardelli, F.; Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M.; Ficcadenti, L.; Gallo, A.; Kalt, R.; Lollo, V.; Palumbo, L.; Piersanti, L.; Schilcher, T.

2016-01-01

The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

Energy Technology Data Exchange (ETDEWEB)

Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Brönnimann, M. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Cardelli, F. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Ficcadenti, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Gallo, A. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Kalt, R. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Lollo, V. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Palumbo, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Piersanti, L., E-mail: luca.piersanti@lnf.infn.it [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Schilcher, T. [Paul Scherrer Institut, 5232 Villigen (Switzerland)

2016-11-21

The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

Dynamics of the Sun-Earth-Moon System

Indian Academy of Sciences (India)

The dynamics of the Sun-Earth-Moon system is discussed with special attention to the effects of. Sun's perturbations on the Moon's orbit around the Earth. Important secular effects are the re- gression of the nodes, the advance of the perigee and the increase in the Moon's mean longitude. We discuss the relationship of the ...

Thermal evaluation of a sun tracking solar cooker

Energy Technology Data Exchange (ETDEWEB)

El-Tous, Yousif; Al-Mofleh, Anwar [Department of Electrical Engineering, Faculty of Engineering Technology, Al-Balqa' Applied University, P.O. Box 15008, Amman (Jordan); Badran, Omar. O. [Department of Mechanical Engineering, Faculty of Engineering Technology, Al-Balqa Appllied University, P.O. Box 15008, Amman (Jordan)

2012-07-01

Solar energy is one of many important types of renewable energy. Jordan is of great needs for renewable energy systems applications since it depends totally in generation of its required energy on imported oil. This study is an experimental work of tracking system developed for enhancing the solar heating using solar cooker. An electronic sun tracking device was used for rotating the solar heater with the movement of the sun. A comparison between fixed and sun tracked cooker showed that the use of sun tracking increased the heating temperature by 36% due to the increase in radiation concentration and using internal mirror reflectors. The programming method used for tracking control works efficiently in all weather conditions regardless of the presence of clouds. It can be used as backup control circuit in which relays are the essential control devices.

The Sun as you never saw it before

Science.gov (United States)

1997-02-01

The remarkable images come from SOHO's visible-light coronagraph LASCO. It masks the intense rays from the Sun's surface in order to reveal the much fainter glow of the solar atmosphere, or corona. Operated with its widest field of view, in its C3 instrument, LASCO's unprecedented sensitivity enables it to see the thin ionized gas of the solar wind out to the edges of the picture, 22 million kilometres from the Sun's surface. Many stars are brighter than the gas, and they create the background scene. The results alter human perceptions of the Sun. Nearly 30 years ago, Apollo photographs of the Earth persuaded everyone of what until then they knew only in theory, that we live on a small planet. Similarly the new imagery shows our motion in orbit around the Sun, and depicts it as one star among - yet close enough to fill the sky emanations that engulf us. For many centuries even astrologers knew that the Sun was in Sagittarius in December and drifting towards the next zodiacal constellation, Capricornus. This was a matter of calculation only, because the Sun's own brightness prevented a direct view of the starfield. The SOHO-LASCO movie makes this elementary point of astronomy a matter of direct observation for the first time. The images are achievable only from a vantage point in space, because the blue glow of the Earth's atmosphere hides the stars during the day. A spacial allocation of observing time, and of data tranmission from the SOHO spacecraft, enabled the LASCO team to obtain large numbers of images over the period 22-28 December 1996. Since then, a sustained effort in image processing, frame by frame, has achieved a result of high technical and aesthetic quality. Only now is the leader of the LASCO team, Guenter Brueckner of the US Naval Research Laboratory, satisfied with the product and ready to authorize its release. "I spend my life examining the Sun," Brueckner says, "but this movie is a special thrill. For a moment I forget the years of effort that

Blinded by the light the secret life of the sun

CERN Document Server

Gribbin, John

1991-01-01

An investigation into the secrets and the new scientific developments which are changing our perceptions of the sun. The book tackles such questions as: does the sun breathe?; can it make sound?; is its centre ice-cold? The new research in sun science will alter our perception not only of the sun, but of the whole universe and add to the understanding of how the world works. The author has also written "Hothouse Earth" and "The Hole in the Sky".

Sun exposure patterns of urban, suburban, and rural children

DEFF Research Database (Denmark)

Bodekær, Mette; Petersen, Bibi; Philipsen, Peter Alshede

2015-01-01

BACKGROUND: Sun exposure is the main etiology of skin cancer. Differences in skin cancer incidence have been observed between rural and urban populations. OBJECTIVES: As sun exposure begins in childhood, we examined summer UVR exposure doses and sun behavior in children resident in urban, suburban......, and rural areas. METHODS: Personal, electronic UVR dosimeters and sun behavior diaries were used during a summer (3.5 months) by 150 children (4-19 years of age) resident in urban, suburban, and rural areas. RESULTS: On school/kindergarten days rural children spent more time outdoors and received higher UVR...... doses than urban and suburban children (rural: median 2.3 h per day, median 0.9 SED per day, urban: median 1.3 h per day, median 0.3 SED per day, suburban: median 1.5 h per day, median 0.4 SED per day) (p ≤ 0.007). Urban and suburban children exhibited a more intermittent sun exposure pattern than rural...

A New Way that Planets can Affect the Sun

Science.gov (United States)

Wolff, Charles; Patrone, Paul

2010-01-01

As planets orbit the Sun, the Sun also has to move to keep the total momentum of the solar system constant. The Sun's small orbital motion plus its 25 day rotation about its axis combine to invigorate some solar instabilities. Occasional convection cells at the proper phase in their short life can be strengthened by factors of two or more. This local burst of extra kinetic energy eventually reaches the surface where it can increase the intensity of solar activity. It might explain some reports in the last century of how planetary positions correlate with solar activity. This is the first effect of planets that is large enough to cause a significant response on the Sun.

Solar flare leaves sun quaking

Science.gov (United States)

1998-05-01

Dr. Alexander G. Kosovichev, a senior research scientist from Stanford University, and Dr. Valentina V. Zharkova from Glasgow (United Kingdom) University found the tell-tale seismic signature in data on the Sun's surface collected by the Michelson Doppler Imager onboard the Solar and Heliospheric Observatory (SOHO) spacecraft immediately following a moderate-sized flare on July 9, 1996. "Although the flare was a moderate one, it still released an immense amount of energy," said Dr. Craig Deforest, a researcher with the SOHO project. "The energy released is equal to completely covering the Earth's continents with a yard of dynamite and detonating it all at once." SOHO is a joint project of the European Space Agency and NASA. The finding is reported in the May 28 issue of the journal Nature, and is the subject of a press conference at the spring meeting of the American Geophysical Union in Boston, Mass., May 27. The solar quake that the science team recorded looks much like ripples spreading from a rock dropped into a pool of water. But over the course of an hour, the solar waves traveled for a distance equal to 10 Earth diameters before fading into the fiery background of the Sun's photosphere. Unlike water ripples that travel outward at a constant velocity, the solar waves accelerated from an initial speed of 22,000 miles per hour to a maximum of 250,000 miles per hour before disappearing. "People have looked for evidence of seismic waves from flares before, but they didn't have a theory so they didn't know where to look," says Kosovichev. Several years ago Kosovichev and Zharkova developed a theory that can explain how a flare, which explodes in space above the Sun's surface, can generate a major seismic wave in the Sun's interior. According to the currently accepted model of solar flares, the primary explosion creates high-energy electrons (electrically charged subatomic particles). These are funneled down into a magnetic flux tube, an invisible tube of magnetic

Protective clothing in the sun | Tamas | Nigerian Journal of Clinical ...

African Journals Online (AJOL)

Sun protecting clothing is clothing designed for sun protection and is producted from the fabric rated for its level ultraviolet (UV) protection. Some textiles and fabrics emloyed in the use of sun protective clothing may be pre-treated with UV inhibiting ingredients during manufacture to enhance their UV blocking capacitiy.

Ancient cults of the sun (German Title: Antike Sonnenkulte)

Science.gov (United States)

Hansen, Rahlf

In ancient astronomy, the heliocentric system of Aristarchus of Samos did not meet universal approval. Contrary to that, the cult of the sun gained immense importance in the Roman Empire. Relics of this significance we still find e.g. in the meaning of the Sunday in the week and in the date of Christmas. The rise of the sun cults is characterised by the merging of different gods from various cultures. Already in classical Greece the god of the sun, Helios, almagated with the god of light, Apollo. The resulting entity was regarded as the harmonic guide of the visible universe, symbolized by Apoll. As well as he plays the lyre, he conducts the cosmos harmonically as the sun. Plato recommends to politicians to study musical harmonics and astronomy in order to get a feeling of the right way to rule the state. In consequence to the conquests of Alexander the Great, the Babylonian star religion was mingled with Greek cosmology and the concept of transmigration of souls. The astrology resulting therefrom spread out over the whole Hellenistic world and was very common in the Roman Empire. The calendar with its religious division of time as the days of the week, following the principle of the gods of the planets governing the hour, was well known. The god of the sun was graded up by the adoption of the calendar of the sun from Egypt by Caesar. Augustus chose Apoll as his guardian god and built with “his” sundial a symbol of the god of the sun, which was visible from a long distance. Augustus used more astral symbols as propaganda of leadership. During the competition with the Parthians, another large empire, for world domination the focus fell on an Iranian god: the Iranian god of light and contract - Mithras. Shortly before 100 A.D., a new cult of mysteries arose in the Roman Empire, called cult of Mithras, and spread quickly. It combined the attributes of a classical sun-god with a religion of salvation, guaranteed by baptism, communion and seven degrees to be passed

Our Explosive Sun

Science.gov (United States)

Brown, D. S.

2009-01-01

The Sun's atmosphere is a highly structured but dynamic place, dominated by the solar magnetic field. Hot charged gas (plasma) is trapped on lines of magnetic force that can snap like an elastic band, propelling giant clouds of material out into space. A range of ground-based and space-based solar telescopes observe these eruptions, particularly…

Surya Namaskar (Sun Salutation): A Path to Good Health

OpenAIRE

Amit Vaibhav; Swati Shukla; Om Prakash Singh

2016-01-01

Surya Namaskar (Sun Salutation) is an ancient and sacred yogic technique of India for expressing gratitude to the Sun. Surya Namaskar is a set of 12 Asanas (postures), It is done preferably in the morning while facing the rising sun. There are numerous health benefits of Surya Namaskar for different system of the body specially musculoskeletal, cardiovascular, gastrointestinal, nervous system, respiratory and endocrinal. The heart, liver, intestine, stomach, chest, throat, legs and backbone a...

Correlates of Sun Protection and Sunburn in Children of Melanoma Survivors.

Science.gov (United States)

Tripp, Mary K; Peterson, Susan K; Prokhorov, Alexander V; Shete, Sanjay S; Lee, Jeffrey E; Gershenwald, Jeffrey E; Gritz, Ellen R

2016-09-01

Sunburns during childhood increase melanoma risk. Children of melanoma survivors are at higher risk, but little is known about their sunburn and sun protection. One study showed that almost half of melanoma survivors' children experienced sunburn in the past year. This study evaluated sunburn and sun protection in melanoma survivors' children, and relevant survivor characteristics from Social Cognitive Theory and the Health Belief Model. Melanoma survivors (N=340) were recruited from a comprehensive cancer center. Survivors completed a baseline questionnaire administered by telephone to report on the behavior of their children (N=340) as part of an RCT of a sun protection intervention. Data were collected in 2008 and analyzed in 2015. In the prior 6 months, 28% of children experienced sunburn. "Always" or "frequent" sun protection varied by behavior: sunscreen, 69%; lip balm, 15%; wide-brimmed hats, 9%; sleeved shirts, 28%; pants, 48%; sunglasses, 10%; shade, 33%; and limiting time outdoors, 45%. Survivors' sunburn and sun protection were positively associated with these outcomes in children. Correlates of sunburn also included older child age and higher risk perceptions. Correlates of sun protection behaviors included younger child age; stronger intentions, higher self-efficacy, and more positive outcome expectations about sun protection; and greater number of melanomas in survivors. Melanoma survivors may have a heightened awareness of the importance of their children's sun protection, but their children are not routinely protected. Correlates of children's sunburn and sun protection suggest subgroups of survivors to target with interventions to improve sun protection. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Preferred solar wind emitting longitudes on the sun

International Nuclear Information System (INIS)

Gosling, J.T.; Asbridge, J.R.; Bame, S.J.; Feldman, W.C.

1977-01-01

During the 11 1/2-year period from July 1964 through December 1975, high- and low-speed solar wind flows originated from preferred solar longitudes. The preferred longitude effect was most pronounced from 1970 onward but was also evident in the years preceding 1970. The most pronounced modulation in average solar wind speed with longitude (approximately 20%) was obtained when it was assumed that the synodic rotation period of the sun is 27.025 days. Some deep internal structure in the sun must ultmately be responsible for these long-lived longitudinal effects, which appear to rotate rigidly with the sun

Sun Protection Among New Zealand Primary School Children.

Science.gov (United States)

Gage, Ryan; Leung, William; Stanley, James; Reeder, Anthony; Mackay, Christina; Smith, Moira; Barr, Michelle; Chambers, Tim; Signal, Louise

2017-12-01

Schools are an important setting for raising skin cancer prevention awareness and encouraging sun protection. We assessed the clothes worn and shade used by 1,278 children in eight schools in the Wellington region of New Zealand. These children were photographed for the Kids'Cam project between September 2014 and March 2015 during school lunch breaks. Children's mean clothing coverage (expressed as a percentage of body area covered) was calculated. Data on school sun-safety policies were obtained via telephone. Mean total body clothing coverage was 70.3% (95% confidence interval = 66.3%, 73.8%). Body regions with the lowest mean coverage were the head (15.4% coverage), neck (36.1% coverage), lower arms (46.1% coverage), hands (5.3% coverage), and calves (30.1% coverage). Children from schools with hats as part of the school uniform were significantly more likely to wear a hat (52.2%) than children from schools without a school hat (2.7%). Most children (78.4%) were not under the cover of shade. Our findings suggest that New Zealand children are not sufficiently protected from the sun at school. Schools should consider comprehensive approaches to improve sun protection, such as the provision of school hats, sun-protective uniforms, and the construction of effective shade.

An autonomous low power high resolution micro-digital sun sensor

NARCIS (Netherlands)

Xie, N.; Theuwissen, A.J.P.

2011-01-01

Micro-Digital Sun Sensor (?DSS) is a sun detector which senses the respective angle between a satellite and the sun. It is composed of a solar cell power supply, a RF communication block and a CMOS Image Sensor (CIS) chip, which is called APS+. The paper describes the implementation of a prototype

Sun Safety Practices Among Schools in the United States.

Science.gov (United States)

Everett Jones, Sherry; Guy, Gery P

2017-05-01

Exposure to the sun's UV radiation is a leading cause of skin cancer. Positive attitudes and beliefs about sun safety behavior, which would make sun protective behavior more likely, could be promoted and supported by school policies and practices. To identify school characteristics associated with having adopted practices that promote sun safety. School-level data from the February 3 to July 23, 2014, School Health Policies and Practices Study's Healthy and Safe School Environment questionnaire were analyzed. The School Health Policies and Practices Study uses a 2-stage sampling design to select a nationally representative sample of schools. All public, state-administered, Catholic, and non-Catholic private schools with any of the grades from kindergarten through 12 were eligible for inclusion. All analyses were conducted using weighted data. Prevalence of sun safety practices. In a nationally representative sample of 828 US schools, representatives of 577 schools (69.7%) responded. Overall, sun safety practices were not common among schools. The most frequent practice was having teachers allow time for students to apply sunscreen at school (47.6%; 95% CI, 42.4%-52.9%). Few schools made sunscreen available for students to use (13.3%; 95% CI, 10.2%-17.0%), almost always or always scheduled outdoor activities to avoid times when the sun was at peak intensity (15.0%; 95% CI, 11.4%-19.6%), or asked parents to ensure that students applied sunscreen before school (16.4%; 95% CI, 12.9%-20.6%). High schools were less likely than elementary schools and middle schools to adopt several practices: for instance, 37.5% of high schools (95% CI, 29.7%-46.0%), 51.6% of middle schools (95% CI, 43.3%-59.7%), and 49.5% of elementary schools (95% CI, 42.0%-57.0%) had teachers allow time for students to apply sunscreen at school, and 11.8% of high schools (95% CI, 7.7%-17.5%), 18.2% of middle schools (95% CI, 13.3%-24.4%), and 14.7% of elementary schools (95% CI, 9.6%-21.8%) almost

The evolution of protostellar envelopes of masses 3 Msub(sun) and 10 Msub(sun)

International Nuclear Information System (INIS)

Yorke, H.W.

1979-10-01

The results of numerical calculations solving the coupled equations of hydrodynamics and radiation transfer are presented in a sequence of papers describing the structure, evolution and appearance of protostellar clouds of intermediate mass (3 Msub(sun) 10 Msub(sun). These numerical calculations begin at the time of initial gravitational collapse and continue through the birth of a central protostar, until the infall of material onto the central object has been reversed. For the 10 M case the formation and evolution of a compact HII region is crudely followed after the gas density in the envelope had decreased sufficiently to allow an ionization front to propagate outwards. For all cases calculated spherical symmetry was assumed. Solar abundances were used. (orig.) 891 WL/orig. 892 RDG

Traditions of the Sun, One Model for Expanding Audience Access

Science.gov (United States)

Hawkins, I.; Paglierani, R.

2006-12-01

The Internet is a powerful tool with which to expand audience access, bringing students, teachers and the public to places and resources they might not otherwise visit or make use of. We will present Traditions of the Sun, an experiential Web site that invites exploration of the world's ancient observatories with special emphasis on Chaco Culture National Historic Park in the Four Corners region of the US and several sites in the Yucatan Peninsula in Mexico. Traditions of the Sun includes resources in English and Spanish along with a unique trilingual on-line book, "Traditions of the Sun, A Photographic Journal," containing explanatory text in Yucatec Maya as well. Traditions of the Sun offers rich opportunities for virtual visits to ancient sites used for solar observing while learning about current NASA research on the Sun and indigenous solar practices within a larger historical and cultural context. The site contains hundreds of photographs, historic images and rich multimedia to help tell the story of the Sun-Earth Connection. Visitors to the site can zoom in on the great Mayan cities of Chichen Itza, Uxmal, Dzibilchaltun, and Mayapan to learn about Mayan astronomy, history, culture, and science. They can also visit Chaco Canyon to watch sunrise over Pueblo Bonito on the summer solstice, take a virtual reality tour of the great kiva at Casa Rinconada or see panoramic vistas from Fajada Butte, an area which, for preservation purposes, is restricted to the public. Traditions of the Sun provides one model of how exploration and discovery can come to life for both formal and informal audiences via the Internet. Traditions of the Sun is a collaborative project between NASA's Sun-Earth Connection Education Forum, the National Park Service, Instituto National de Antropologia e Historia, Universidad Nacional Autonoma de Mexico, and Ideum.

The sun as a star: Solar phenomena and stellar applications

International Nuclear Information System (INIS)

Noyes, R.W.

1981-01-01

Our Sun is a run-of-the-mill star, having no obvious extremes of stellar properties. For this reason it is perhaps more, rather than less, interesting as an astrophysical object, for its sameness to other stars suggests that in studying the Sun, we are studying at close hand common, rather than unusual stellar phenomena. Conversely, comparative study of the Sun and other solar-type stars is an invaluable tool for solar physics, for two reasons: First, it allows us to explore how solar properties and phenomena depend on parameters we cannot vary on the Sun - most fundamentally, rotation rate and mass. Second, study of solar-like stars of different ages allows us to see how stellar and solar phenomena depend on age; study of other stars may be one of the best ways to infer the earlier history of the Sun, as well as its future history. In this review we shall concentrate on phenomena common to the Sun and solar-type (main sequence) stars with different fundamental properties such as mass, age, and rotation. (orig.)

The relationship between sun protection policies and practices in schools with primary-age students: the role of school demographics, policy comprehensiveness and SunSmart membership.

Science.gov (United States)

Dono, J; Ettridge, K A; Sharplin, G R; Wilson, C J

2014-02-01

Schools can implement evidence-based sun protection policies that guide practices to help protect children from harmful sun exposure. This national study assessed the relationship between the existence and comprehensiveness of written policies and the comprehensiveness of sun protection practices. The impact of school demographics on the strength of the relationship was also examined, as was the possibility that 'SunSmart' membership would have an additional impact on practices, beyond having any formal policy. In 2011-12, staff members of 1573 schools catering to primary-age students completed a self-administered survey about sun protection policies and practices (response rate of 57%). Results showed that schools with a written policy had more comprehensive practices than schools without a written policy. The relationship between having a written policy and sun protection practices was stronger for remote schools compared with metropolitan and regional schools, and for schools catering to both primary and secondary students compared with primary students only. In addition, policy comprehensiveness was associated with practice comprehensiveness, and SunSmart membership was indirectly related to practice comprehensiveness via policy comprehensiveness. These results indicate that written policies relate to practice comprehensiveness, but the strength of the association can vary according to the characteristics of the organization.

Eruptions from the Sun

Science.gov (United States)

Kohler, Susanna

2015-11-01

The Sun often exhibits outbursts, launching material from its surface in powerful releases of energy. Recent analysis of such an outburst captured on video by several Sun-monitoring spacecraft may help us understand the mechanisms that launch these eruptions.Many OutburstsSolar jets are elongated, transient structures that are thought to regularly release magnetic energy from the Sun, contributing to coronal heating and solar wind acceleration. Coronal mass ejections (CMEs), on the other hand, are enormous blob-like explosions, violently ejecting energy and mass from the Sun at incredible speeds.But could these two types of events actually be related? According to a team of scientists at the University of Science and Technology of China, they may well be. The team, led by Jiajia Liu, has analyzed observations of a coronal jet that they believe prompted the launch of a powerful CME.Observing an ExplosionGif of a movie of the CME, taken by the Solar Dynamics Observatorys Atmospheric Imaging Assembly at a wavelength of 304. The original movie can be found in the article. [Liu et al.]An army of spacecraft was on hand to witness the event on 15 Jan 2013 including the Solar Dynamics Observatory (SDO), the Solar and Heliospheric Observatory (SOHO), and the Solar Terrestrial Relations Observatory (STEREO). The instruments on board these observatories captured the drama on the northern limb of the Sun as, at 19:32 UT, a coronal jet formed. Just eight minutes later, a powerful CME was released from the same active region.The fact that the jet and CME occurred in the same place at roughly the same time suggests theyre related. But did the initial motions of the CME blob trigger the jet? Or did the jet trigger the CME?Tying It All TogetherIn a recently published study, Liu and collaborators analyzed the multi-wavelength observations of this event to find the heights and positions of the jet and CME. From this analysis, they determined that the coronal jet triggered the release

Global Warming Blame the Sun

CERN Document Server

Calder, N

1997-01-01

Concern about climate change reaches a political peak at a UN conference in Kyoto, 1-10 December, but behind the scenes the science is in turmoil. A challenge to the hypothesis that greenhouse gases are responsible for global warming comes from the discovery that cosmic rays from the Galaxy are involved in making clouds (Svensmark and Friis-Christensen, 1997). During the 20th Century the wind from the Sun has grown stronger and the count of cosmic rays has diminished. With fewer clouds, the EarthÕs surface has warmed up. This surprising mechanism explains the link between the Sun and climate change that astronomers and geophysicists have suspected for 200 years.

The Sun Radio Imaging Space Experiment (SunRISE) Mission

Science.gov (United States)

Kasper, J. C.; Lazio, J.; Alibay, F.; Amiri, N.; Bastian, T.; Cohen, C.; Landi, E.; Hegedus, A. M.; Maksimovic, M.; Manchester, W.; Reinard, A.; Schwadron, N.; Cecconi, B.; Hallinan, G.; Krupar, V.

2017-12-01

Radio emission from coronal mass ejections (CMEs) is a direct tracer of particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Energized electrons excite Langmuir waves, which then convert into intense radio emission at the local plasma frequency, with the most intense acceleration thought to occur within 20 R_S. The radio emission from CMEs is quite strong such that only a relatively small number of antennas is required to detect and map it, but many aspects of this particle acceleration and transport remain poorly constrained. Ground-based arrays would be quite capable of tracking the radio emission associated with CMEs, but absorption by the Earth's ionosphere limits the frequency coverage of ground-based arrays (nu > 15 MHz), which in turn limits the range of solar distances over which they can track the radio emission (concept: A constellation of small spacecraft in a geostationary graveyard orbit designed to localize and track radio emissions in the inner heliosphere. Each spacecraft would carry a receiving system for observations below 25 MHz, and SunRISE would produce the first images of CMEs more than a few solar radii from the Sun. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

Ultraviolet radiation, sun damage and preventing

International Nuclear Information System (INIS)

Johnsen, B.; Christensen, T.; Nilsen, L.T.; Hannevik, M.

2013-01-01

The report focuses on the large impact of health damages due to excessive UV exposure from natural sun. The first part of the report gives background information on factors significantly affecting the intensity of UV radiation. The second part gives an overview of health effects related to UV exposure, with recommendations on how to avoid excessive UV exposure and still enjoy the positive sides of outdoor activity. The report is intended to contribute to informational activities about sun exposure as recommended by the World Health Organisation and the World Meteorology Organisation. (Author)

Variation of the quiet sun at 21 cm - 1981-1987

International Nuclear Information System (INIS)

Bastian, T.S.; Dulk, G.A.

1988-01-01

The sun was imaged at a wavelength of about 21 cm during 1981-1987 using the VLA, the Green Bank 91-m telescope, the Arecibo 305 m telescope, and powerful maximum entropy image reconstruction techniques. There was a systematic decrease in the quiet sun's brightness temperature at 21 cm as the sun declined from sunspot maximum to sunspot minimum; this was accompanied by a systematic decrease in the sun's radius. The two-fold decrease in the electron number density in the solar transition region and low corona could have been the cause of these variations. 7 references

Sun safety in construction: a U.K. intervention study.

Science.gov (United States)

Houdmont, J; Madgwick, P; Randall, R

2016-01-01

Interventions to promote sun safety in the U.K. construction sector are warranted given the high incidence of skin cancer attributable to sun exposure relative to other occupational groups. To evaluate change in sun safety knowledge and practices among construction workers in response to an educational intervention. A baseline questionnaire was administered, followed by a bespoke sector-specific DVD-based intervention. At 12-month follow-up, participants completed a further questionnaire. Analyses were conducted on a sample of 120 workers (intervention group, n = 70; comparison group, n = 50). At follow-up, the proportion of intervention group participants that reported correct sun safety knowledge was not significantly greater than at baseline. However, the intervention group demonstrated significant positive change on 9 out of 10 behavioural measures, the greatest change being use of a shade/cover when working in the sun followed by regularly checking skin for moles or unusual changes. Exposure to this intervention was linked to some specific positive changes in construction workers' self-reported sun safety practices. These findings highlight the potential for educational interventions to contribute to tackling skin cancer in the UK construction sector. The findings support the development of bespoke educational interventions for other high-risk outdoor worker groups. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Validity and Stability of the Decisional Balance for Sun Protection Inventory

OpenAIRE

Hui-Qing Yin; Joseph S. Rossi; Colleen A. Redding; Andrea L. Paiva; Steven F. Babbin; Wayne F. Velicer

2014-01-01

The 8-item Decisional Balance for sun protection inventory (SunDB) assesses the relative importance of the perceived advantages (Pros) and disadvantages (Cons) of sun protective behaviors. This study examined the psychometric properties of the SunDB measure, including invariance of the measurement model, in a population-based sample of N = 1336 adults. Confirmatory factor analyses supported the theoretically based 2-factor (Pros, Cons) model, with high internal consistencies for each subscale...

SCIENCE OF SUN PHOTOMETRY

Directory of Open Access Journals (Sweden)

Alexandru Dan Toma

2013-07-01

Full Text Available Typically, the total amount of gases and particles in a column of atmosphere cannot be determined from measurements just at Earth's surface, by a single measurement essentially at the bottom of the atmosphere column. Balloons, airplanes, and rockets are all used to perform direct measurements in the atmosphere at altitudes up to and beyond the stratosphere. Satellite-based instruments provide global views, but it is difficult to infer surface and column distributions from space-based measurements, so such measurements must still be supplemented by ground-based measurements. Sun photometry is an important way of probing the atmosphere from the ground to measure the effects of the atmosphere on Sun radiation crossing through the atmosphere to Earth's surface. These indirect technique provide information about the entire atmosphere above the observer, not just the atmosphere that can be sampled directly close to Earth's surface.

Sun protection and skin self-examination in melanoma survivors.

Science.gov (United States)

Mujumdar, Urvi J; Hay, Jennifer L; Monroe-Hinds, Yvette C; Hummer, Amanda J; Begg, Colin B; Wilcox, Homer B; Oliveria, Susan A; Berwick, Marianne

2009-10-01

Patients diagnosed with melanoma are at risk for developing recurrent and second primary disease. Skin self-examination (SSE) and sun protection are standard clinical recommendations to minimize risk. In this study we examined performance of these behaviors in individuals with melanoma drawn from the general population. Potential participants (N=148) with a first primary melanoma diagnosed in 2000 were identified through a population-based cancer registry in New Jersey, USA. One hundred and fifteen individuals participated in a 30 min telephone interview concerning behavioral adherence with SSE and sun protection, self-efficacy for performing these behaviors, and perceived risk of developing another skin cancer. We utilized logistic regression to estimate potential associations of demographic, medical, and psychosocial factors with SSE and sun protection, respectively. Seventeen percent of subjects reported performing comprehensive SSE at least once every two months and 23% engaged in regular sun protection. Utilization of SSE was related to the presence of moles (OR=4.2, 95% CI: 1.1-15) and higher SSE self-efficacy (OR=14.4, 95% CI: 1.9-112). Regular sun protection was related to older age (>60 years; OR=3.3, 95% CI: 1.3-8.7), being female (OR=2.8, 95% CI: 1.1-7.3), and higher sun protection self-efficacy (OR=5.0, 95% CI: 1.4-18). These factors remained significant in multivariate models. In this group of primary melanoma survivors, the rates of SSE and sun protection are comparable to, but do not exceed, general population estimates. This study provides justification for further research to address barriers to prevention and control behaviors in melanoma survivors.

Nearest star the surprising science of our sun

CERN Document Server

Golub, Leon

2014-01-01

How did the Sun evolve, and what will it become? What is the origin of its light and heat? How does solar activity affect the atmospheric conditions that make life on Earth possible? These are the questions at the heart of solar physics, and at the core of this book. The Sun is the only star near enough to study in sufficient detail to provide rigorous tests of our theories and help us understand the more distant and exotic objects throughout the cosmos. Having observed the Sun using both ground-based and spaceborne instruments, the authors bring their extensive personal experience to this sto

Outdoor Workers and Sun Protection: Knowledge and Behaviour

Directory of Open Access Journals (Sweden)

Jane Cioffi

2012-11-01

Full Text Available Outdoor workers are at high risk of developing skin cancer. Primary prevention can potentiallyreduce the incidence of skin cancer in this group. This study aimed to determine theknowledge and sun protective behaviour of outdoor workers towards skin cancer. A shortquestionnaire was used to collect data from workers on construction sites during workinghours. Despite workers having knowledge of the risks of skin cancer their use of sun protectionwas less than satisfactory, particularly considering their cumulative exposure.Workplace health education programs for outdoor workers addressing sun protection areindicated, as is further research to increase understanding of issues workers have withsun protection in the workplace.

Validity and Stability of the Decisional Balance for Sun Protection Inventory

Directory of Open Access Journals (Sweden)

Hui-Qing Yin

2014-01-01

Full Text Available The 8-item Decisional Balance for sun protection inventory (SunDB assesses the relative importance of the perceived advantages (Pros and disadvantages (Cons of sun protective behaviors. This study examined the psychometric properties of the SunDB measure, including invariance of the measurement model, in a population-based sample of N=1336 adults. Confirmatory factor analyses supported the theoretically based 2-factor (Pros, Cons model, with high internal consistencies for each subscale (α≥.70. Multiple-sample CFA established that this factor pattern was invariant across multiple population subgroups, including gender, racial identity, age, education level, and stage of change subgroups. Multivariate analysis by stage of change replicated expected patterns for SunDB (Pros η2=.15, Cons η2=.02. These results demonstrate the internal and external validity and measurement stability of the SunDB instrument in adults, supporting its use in research and intervention.

A sun holiday is a sunburn holiday.

Science.gov (United States)

Petersen, Bibi; Thieden, Elisabeth; Philipsen, Peter Alshede; Heydenreich, Jakob; Young, Antony Richard; Wulf, Hans Christian

2013-08-01

Many people take holidays in sunny locations with the express aim of sunbathing. This may result in sunburn, which is a risk factor for skin cancer. We investigated 25 Danish sun seekers during a week's holiday in the Canary Islands. The percentage of body surface area with sunburn was determined by daily skin examinations by the same observer. Erythemally effective ultraviolet radiation (UVR) exposure was assessed with time-stamped personal dosimeters worn on the wrist. Volunteers reported their clothing cover and sunscreen use in diaries, and this information was used to determine body site-specific UVR doses after adjustment for sun protection factor. Remarkably, we found that all volunteers sunburned at some point. The risk of sunburn correlated significantly with the adjusted body site-specific UVR dose. Furthermore, there was also a significant relationship between the daily UVR dose and percentage of body surface area with sunburn. Our study shows that holiday UVR exposure results in a high risk of sunburn, which potentially increases the risk of skin cancer. Possible protection by melanogenesis is insufficient to protect against sunburn during a 1-week sun holiday. Finally, our data clearly support a substantial skin cancer risk from sun holidays. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sunwatchers Across Time: Sun-Earth Day from Ancient and Modern Solar Observatories

Science.gov (United States)

Hawkins, I.; Vondrak, R.

Humans across all cultures have venerated, observed, and studied the Sun for thousands of years. The Sun, our nearest star, provides heat and energy, is the cause of the seasons, and causes space weather effects that influence our technology-dependent society. The Sun is also part of indigenous tradition and culture. The Inca believed that the Sun had the power to make things grow, and it does, providing us with the heat and energy that are essential to our survival. From a NASA perspective, Sun-Earth Connection research investigates the effects of our active Sun on the Earth and other planets, namely, the interaction of the solar wind and other dynamic space weather phenomena with the solar system. We present plans for Sun-Earth Day 2005, a yearly celebration of the Sun-Earth Connection sponsored by the NASA Sun-Earth Connection Education Forum (SECEF). SECEF is one of four national centers of space science education and public outreach funded by NASA Office of Space Science. Sun-Earth Day involves an international audience of schools, science museums, and the general public in activities and events related to learning about the Sun-Earth Connection. During the year 2005, the program will highlight cultural and historical perspectives, as well as NASA science, through educational and public outreach events intended to involve diverse communities. Sun-Earth Day 2005 will include a series of webcasts from solar observatories produced by SECEF in partnership with the San Francisco Exploratorium. Webcasts from Chaco Culture National Historical Park in New Mexico, USA, and from Chichen Itza, Mexico, will be accessed by schools and the public. Sun-Earth Day will also feature NASA Sun-Earth Connection research, missions, and the people who make it possible. One of the goals of this talk is to inform and engage COSPAR participants in these upcoming public events sponsored by NASA. Another goal is to share best practices in public event programming, and present impact

SunShot Vision Study: February 2012 (Book)

Energy Technology Data Exchange (ETDEWEB)

2012-02-01

The objective of the SunShot Vision Study is to provide an in-depth assessment of the potential for solar technologies to meet a significant share of electricity demand in the United States during the next several decades. Specifically, it explores a future in which the price of solar technologies declines by about 75% between 2010 and 2020 - in line with the U.S. Department of Energy (DOE) SunShot Initiative's targets.

Trends in reported sun bed use, sunburn, and sun care knowledge and attitudes in a U.K. region: results of a survey of the Northern Ireland population.

Science.gov (United States)

Boyle, R; O'Hagan, A H; Donnelly, D; Donnelly, C; Gordon, S; McElwee, G; Gavin, A

2010-12-01

Sunburn and sun bed use increase risk of malignant melanoma, the incidence of which continues to rise. To document trends in reported sun bed use, sunburn, and sun care knowledge and attitudes in a U.K. region where there have been 20 years of sun-related health promotion campaigns. In 2000, 2004 and 2008, a 'care in the sun' module was included in the Northern Ireland (NI) Omnibus survey. Each year 2200 subjects aged 16 years and over were randomly selected and invited to complete a sun-related questionnaire. Proportions of respondents were analysed by demographic and socioeconomic factors, with differences tested using z-tests and the χ(2) -squared test. In total, 3623 persons responded (response rate 50-59%). Skin cancer knowledge in 2008 was high at 97%. Skin type reporting was inaccurate and since 2000 has become weighted towards the darker Fitzpatrick skin types IV and V (χ(2) = 21·5, P = 0·006). Reported sunburn rose over the 8-year period to 60% in 2008, with 39% of those aged 16-24 years reporting sunburn at least once in the previous year. Twenty per cent reported sun bed use in 2008, a fall from 28% in 2004 (P = 0·01), with greater reported use among those aged 16-24 years (24%) and among women (31% vs. 9% men, P sunburn pose risks for further rises in skin cancer. Barriers for future sun care campaigns to address include poorer sun care knowledge among men, poor skin type awareness, and women's attitudes regarding the health and attractiveness of tanning. Sun bed use, although high, has fallen, possibly in response to recent campaigns. © 2010 The Authors. BJD © 2010 British Association of Dermatologists.

The 136 MHz/400 MHz earth station antenna-noise temperature prediction program documentation for RAE-B

Science.gov (United States)

Chin, M.

1972-01-01

A simulation study to determine the 136 MHz and 400 MHz noise temperature of the ground network antennas which will track the RAE-B satellite during data transmission periods is described. Since the noise temperature of the antenna effectively sets the signal-to-noise ratio (SNR) of the received signal, a knowledge of SNR will be helpful in locating the optimum time windows for data transmission during low-noise periods. Antenna-noise temperatures at 136 MHz and 400 MHz will be predicted for selected earth-based ground stations which will support RAE-B. The antenna-noise temperature predictions will include the effects of galactic-brightness temperature, the sun, and the brightest radio stars. Predictions will cover the ten-month period from March 1, 1973 to December 31, 1973. The RAE-B mission will be expecially susceptible to SNR degradation during the two eclipses of the Sun occurring in this period.

Relationship Factors and Couples' Engagement in Sun Protection

Science.gov (United States)

Manne, S. L.; Coups, E. J.; Kashy, D. A.

2016-01-01

Individuals may be more motivated to adopt health practices if they consider the benefits of these behaviors for their close relationships. The goal of this study was to examine couple concordance with sun protection and use the interdependence and communal coping theory to evaluate the role of relationship factors in sun protection. One hundred…

Sun behaviour on the beach monitored by webcam photos.

Science.gov (United States)

Heerfordt, I M; Philipsen, P A; Wulf, H C

2018-02-01

To prevent skin cancer, the general population is recommended to limit time in the sun, to wear clothes and to seek shade around noon. This study aimed to investigate the number of beachgoers, the duration of sun exposure, and clothing worn during the day on a beach in Copenhagen. Observational, descriptive study. On 11 beach days in 2014 and 2015, beachgoers were counted every hour from 8:00 to 20:00. It was noted if they wore clothes or swimwear. To estimate the duration of sun exposure, it was noted how long cars were parked by the beach. Of the counted beachgoers 46% were present from noon to 15:00. The number of beachgoers peaked at 15:00 on weekend days (Saturdays and Sunday) and at 16:00 on working days (Monday to Friday). Both on weekend days and working days, the percentage of beachgoers wearing clothes was lowest at 13:00 when about 90% wore only swimwear. Cars were parked for 117 min on average. Around noon, the mean time expanded to 142 min. We assume this to reflect the duration of a beach visit. The results indicate a weak tendency to limit time in the sun and to seek shade when the ultraviolet radiation is strongest in the midday sun. Hopefully information about actual sun behaviour can be used to adjust campaigns. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Leptotene/zygotene chromosome movement via the SUN/KASH protein bridge in Caenorhabditis elegans.

Science.gov (United States)

Baudrimont, Antoine; Penkner, Alexandra; Woglar, Alexander; Machacek, Thomas; Wegrostek, Christina; Gloggnitzer, Jiradet; Fridkin, Alexandra; Klein, Franz; Gruenbaum, Yosef; Pasierbek, Pawel; Jantsch, Verena

2010-11-24

The Caenorhabditis elegans inner nuclear envelope protein matefin/SUN-1 plays a conserved, pivotal role in the process of genome haploidization. CHK-2-dependent phosphorylation of SUN-1 regulates homologous chromosome pairing and interhomolog recombination in Caenorhabditis elegans. Using time-lapse microscopy, we characterized the movement of matefin/SUN-1::GFP aggregates (the equivalent of chromosomal attachment plaques) and showed that the dynamics of matefin/SUN-1 aggregates remained unchanged throughout leptonene/zygotene, despite the progression of pairing. Movement of SUN-1 aggregates correlated with chromatin polarization. We also analyzed the requirements for the formation of movement-competent matefin/SUN-1 aggregates in the context of chromosome structure and found that chromosome axes were required to produce wild-type numbers of attachment plaques. Abrogation of synapsis led to a deceleration of SUN-1 aggregate movement. Analysis of matefin/SUN-1 in a double-strand break deficient mutant revealed that repair intermediates influenced matefin/SUN-1 aggregate dynamics. Investigation of movement in meiotic regulator mutants substantiated that proper orchestration of the meiotic program and effective repair of DNA double-strand breaks were necessary for the wild-type behavior of matefin/SUN-1 aggregates.

Data on the association of the nuclear envelope protein Sun1 with nucleoli.

Science.gov (United States)

Moujaber, Ossama; Omran, Nawal; Kodiha, Mohamed; Pié, Brigitte; Cooper, Ellis; Presley, John F; Stochaj, Ursula

2017-08-01

SUN proteins participate in diverse cellular activities, many of which are connected to the nuclear envelope. Recently, the family member SUN1 has been linked to novel biological activities. These include the regulation of nucleoli, intranuclear compartments that assemble ribosomal subunits. We show that SUN1 associates with nucleoli in several mammalian epithelial cell lines. This nucleolar localization is not shared by all cell types, as SUN1 concentrates at the nuclear envelope in ganglionic neurons and non-neuronal satellite cells. Database analyses and Western blotting emphasize the complexity of SUN1 protein profiles in different mammalian cells. We constructed a STRING network which identifies SUN1-related proteins as part of a larger network that includes several nucleolar proteins. Taken together, the current data highlight the diversity of SUN1 proteins and emphasize the possible links between SUN1 and nucleoli.

The COST example for outreach to the general public: I love my Sun

Science.gov (United States)

Tulunay, Yurdanur; Crosby, Norma Bock; Tulunay, Ersin; Calders, Stijn; Parnowski, Aleksei; Sulic, Desanka

2013-01-01

It is important to educate children about the important role that the Sun has in their lives. This paper presents an educational outreach tool entitled "I Love My Sun" that has been developed for school children in the approximate age range of 7 through 11 years. The main objective of this tool is to make children aware of space weather, the Sun, Sun-Earth relations and how they, the children, are part of this global picture. Children are given a lecture about the Sun. The lecture is preceded and followed by the children drawing a picture of the Sun. In this paper the background behind the "I Love My Sun" initiative is given and it is described how to perform an "I Love My Sun". The main results from events in Turkey, Belgium, Ukraine and Serbia are presented.

The Sun

International Nuclear Information System (INIS)

Hejna, L.; Sobotka, M.

1987-01-01

The conference proceedings contain 50 papers classified in six parts. The introductory paper is devoted to magnetic fields of the Sun and of low-mass main-sequence stars. 7 papers discuss the morphology and fine structure of solar active regions, 9 papers deal with evolutionary aspects of the regions, 6 papers with observations and theories of the solar magnetic field, 9 deal with velocity fields, oscillations and waves in the active regions and 18 papers discuss the physical structure of active regions and its diagnostics. (M.D.). 218 figs., 19 tabs., 1,317 refs

Suns-VOC characteristics of high performance kesterite solar cells

Science.gov (United States)

Gunawan, Oki; Gokmen, Tayfun; Mitzi, David B.

2014-08-01

Low open circuit voltage (VOC) has been recognized as the number one problem in the current generation of Cu2ZnSn(Se,S)4 (CZTSSe) solar cells. We report high light intensity and low temperature Suns-VOC measurement in high performance CZTSSe devices. The Suns-VOC curves exhibit bending at high light intensity, which points to several prospective VOC limiting mechanisms that could impact the VOC, even at 1 sun for lower performing samples. These VOC limiting mechanisms include low bulk conductivity (because of low hole density or low mobility), bulk or interface defects, including tail states, and a non-ohmic back contact for low carrier density CZTSSe. The non-ohmic back contact problem can be detected by Suns-VOC measurements with different monochromatic illuminations. These limiting factors may also contribute to an artificially lower JSC-VOC diode ideality factor.

The Maunder minimum and the variable sun-earth connection

CERN Document Server

Wei Hock Soon, Willie

2003-01-01

This book takes an excursion through solar science, science history, and geoclimate with a husband and wife team who revealed some of our sun's most stubborn secrets. E Walter and Annie S D Maunder's work helped in understanding our sun's chemical, electromagnetic and plasma properties. They knew the sun's sunspot migration patterns and its variable, climate-affecting, inactive and active states in short and long time frames. An inactive solar period starting in the mid-seventeenth century lasted approximately seventy years, one that E Walter Maunder worked hard to make us understand: the Maun

Quadrant to Measure the Sun's Altitude

Science.gov (United States)

Windsor, A Morgan, Jr.

2013-01-01

The changing altitude of the Sun (either over the course of a day or longer periods) is a phenomenon that students do not normally appreciate. However, the altitude of the Sun affects many topics in disciplines as diverse as astronomy, meteorology, navigation, or horology, such as the basis for seasons, determination of latitude and longitude, or…

How to Improve Adolescents' Sun Protection Behavior? Age and Gender Issues

Science.gov (United States)

Paul, Christine; Tzelepis, Flora; Parfitt, Nicholas; Girgis, Afaf

2008-01-01

Objective: To explore adolescents' self-reported reasons for sun protection, as adolescents as a group continue to have poor sun protection practices. Methods: Seventeen age- and gender-segregated focus groups were conducted in Australian high schools. Results: Reasons for using sun protection included personal comfort, appearance, policies, fear…

76 FR 20992 - Sun Chemical Corp.; Filing of Color Additive Petition

Science.gov (United States)

2011-04-14

...] Sun Chemical Corp.; Filing of Color Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing that Sun Chemical Corp. has... given that a color additive petition (CAP 1C0290) has been filed by Sun Chemical Corp., 5020 Spring...

Measuring sun exposure in epidemiological studies: Matching the method to the research question.

Science.gov (United States)

King, Laura; Xiang, Fan; Swaminathan, Ashwin; Lucas, Robyn M

2015-12-01

Sun exposure has risks and benefits for health. Testing these associations requires tools for measuring sun exposure that are feasible and relevant to the time-course of the health outcome. Recent sun exposure, e.g. the last week, is best captured by dosimeters and sun diaries. These can also be used for medium-term sun exposure e.g. over several weeks, but incur a high participant burden. Self-reported data on "typical time outdoors" for working and non-working days, is less detailed and not influenced by day-to-day variation. Over a longer period, e.g. the lifetime, or for particular life stages, proxies of sun exposure, such as latitude of residence or ambient ultraviolet (UV) radiation levels (from satellites or ground-level monitoring) can be used, with additional detail provided by lifetime sun exposure calendars that include locations of residence, usual time outdoors, and detail of sunburn episodes. Objective measures of lifetime sun exposure include microtopography of sun-exposed skin (e.g. using silicone casts) or conjunctival UV autofluorescence. Potential modifiers of the association between sun exposure and the health outcome, such as clothing coverage and skin colour, may also need to be measured. We provide a systematic approach to selecting sun exposure measures for use in epidemiological health research. Copyright © 2015 Elsevier B.V. All rights reserved.

Parents' knowledge, attitudes and beliefs regarding sun protection in children: a qualitative study.

Science.gov (United States)

Littlewood, Zoe; Greenfield, Sheila

2018-02-01

Childhood is a critical period for sun protection, when the skin is particularly susceptible to the carcinogenic effects of ultraviolet radiation. Children are dependent upon parents to implement sun protective measures. Existing qualitative research exploring parents' attitudes and beliefs underpinning children's sun protection is from Australia, which has the highest melanoma incidence rates globally, and thus benefits from widespread sun protection awareness campaigns. Parents' sun protective behaviour may, therefore, differ between Australia and the UK. This study investigates the topic in a UK context, using qualitative methodology to gain detailed insights into a relatively under-researched area. The aim of the study was to explore parents' knowledge and understanding of sun protection in children, and factors that motivate and challenge them in this area. Finally, it aimed to determine if and how ethnicity and skin type influence these attitudes and beliefs. Twenty-two semi-structured individual interviews were carried out with parents of children aged 5 years or younger, recruited from local nurseries. Transcripts were analysed using thematic analysis. Four overarching themes emerged, each incorporating two to three sub-themes. 'Attitudes towards children's sun protection' refers to the fact that parents considered sun protection to be important for children, a finding which was consistent between different skin types. 'Sun protection practices' brings together several protective behaviours adopted in children and, to a lesser degree, in parents, and their associated disadvantages. 'Sun safety knowledge' refers to parents' awareness of the risks of sun exposure and the need for protection, and illustrates where gaps in knowledge exist, such as regarding the need for vitamin D, and the importance of vigilant sun protection even in the UK. Finally, 'motivating and facilitating factors' highlights motivations for sun protection in children, and factors that

The New Sun-Sky-Lunar Cimel CE318-T Multiband Photometer - A Comprehensive Performance Evaluation

Science.gov (United States)

Barreto, Africa; Cuevas, Emilio; Granados-Munoz, Maria-Jose; Alados-Arboledas, Lucas; Romero, Pedro M.; Grobner, Julian; Kouremeti, Natalia; Almansa, Antonio F.; Stone, Tom; Toledano, Carlos;

A sun holiday is a sunburn holiday

DEFF Research Database (Denmark)

Petersen, Bibi; Thieden, Elisabeth; Philipsen, Peter Alshede

2013-01-01

Many people take holidays in sunny locations with the express aim of sunbathing. This may result in sunburn, which is a risk factor for skin cancer. We investigated 25 Danish sun seekers during a week's holiday in the Canary Islands. The percentage of body surface area with sunburn was determined......-specific UVR doses after adjustment for sun protection factor. Remarkably, we found that all volunteers sunburned at some point. The risk of sunburn correlated significantly with the adjusted body site-specific UVR dose. Furthermore, there was also a significant relationship between the daily UVR dose...... and percentage of body surface area with sunburn. Our study shows that holiday UVR exposure results in a high risk of sunburn, which potentially increases the risk of skin cancer. Possible protection by melanogenesis is insufficient to protect against sunburn during a 1-week sun holiday. Finally, our data...

The Sun among the stars. Pt. 3

International Nuclear Information System (INIS)

Hardorp, J.

1980-01-01

Energy distributions from 3308 to 8390 Angstroem of two candidates for a solar spectral analog and of 14 other northern G-type dwarfs are compared to the solar energy distribution via stellar spectrophotometric standards. The reliability of the stellar and solar flux-calibrations is evaluated. While the stellar calibration seems to be in good shape, solar calibrations differ widely. Labs.and Neckel's calibration is the best match to the energy distributions from 4500 to 8390 Angstroem of those four stars that share the Sun's ultraviolet line spectrum (16 Cyg B, G5V, and the three Hyades stars VB 64, 106, and 142). Below 4500 Angstroem, discrepancies of up to 6% remain which do not seem to be genuine Sun-star differences. An error in the Labs and Neckel tables between 5700 and 6000 Angstroem is corrected. The NASA Standard Tables of Solar Spectral Irradiance cannot be trusted, since there seems to be no star in the sky that look like the NASA-sun. The four stars mentioned are taken to be perfect solar spectral analogs. An improved table of solar spectral irradiance is then given by the magnitudes of 16 Cyg B minus 32.945, based on Tueg's atellar and Labs and Neckel's solar calibrations. The Sun's place in the UBV system is V = -26.71 +- 0.03, B-V = 0.665 +- 0.005, and U-B = 0.20 +- 0.01. Most previous photometric investigations found a bluer Sun because they used the wrong solar calibration. For deriving accurate albedos of planets, any one of the calibrated G-type stars can be used as a standard star, when corrections are applied, although the solar analogs themselves are to be preferred. The MK system of spectral classification should be revised. (orig.)

Real-time sun protection decisions in first-degree relatives of melanoma patients.

Science.gov (United States)

Hay, Jennifer L; Shuk, Elyse; Schofield, Elizabeth; Loeb, Rebecca; Holland, Susan; Burkhalter, Jack; Li, Yuelin

2017-09-01

Melanoma is the most serious skin cancer, and consistent use of sun protection is recommended to reduce risk. Yet sun protection use is generally inconsistent. Understanding the decisional factors driving sun protection choices could aid in intervention development to promote sun protection maintenance. In 59 first-degree relatives of melanoma patients, an interactive voice response system (IVRS) on participants' cell phones was used to assess twice daily (morning, afternoon) real-time sun protection usage (sunscreen, shade, hats, protective clothing) and decision factors (weather, type of activity, convenience, social support) over a 14-day summer interval where morning and afternoon outdoor exposures were anticipated. Generalized estimating equations and hierarchical linear models were used to examine the effect of demographics and decisional factors on sun protection choices over time. Sun protection use was inconsistent (e.g., 61% used sunscreen inconsistently). Most strategies were used independently, with the exception of moderate overlap of sunscreen and hat usage. Decision factors were highly relevant for sun protection. For instance, sunscreen use was related to the perception of having adequate time to apply it, whereas shade and hat usage were each related to convenience. Few findings emerged by gender, age, time of day, or year. Significant within-subject variation remained, however. The findings support continued examination of decision factors in understanding sun protection consistency in real time. Interventions where cues to action and environmental supports work together in varied settings can be developed to improve sun protection maintenance in populations at risk for this common disease. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

ON SUN-TO-EARTH PROPAGATION OF CORONAL MASS EJECTIONS

International Nuclear Information System (INIS)

Liu, Ying D.; Luhmann, Janet G.; Möstl, Christian; Bale, Stuart D.; Lin, Robert P.; Lugaz, Noé; Davies, Jackie A.

2013-01-01

We investigate how coronal mass ejections (CMEs) propagate through, and interact with, the inner heliosphere between the Sun and Earth, a key question in CME research and space weather forecasting. CME Sun-to-Earth kinematics are constrained by combining wide-angle heliospheric imaging observations, interplanetary radio type II bursts, and in situ measurements from multiple vantage points. We select three events for this study, the 2012 January 19, 23, and March 7 CMEs. Different from previous event studies, this work attempts to create a general picture for CME Sun-to-Earth propagation and compare different techniques for determining CME interplanetary kinematics. Key results are obtained concerning CME Sun-to-Earth propagation: (1) the Sun-to-Earth propagation of fast CMEs can be approximately formulated into three phases: an impulsive acceleration, then a rapid deceleration, and finally a nearly constant speed propagation (or gradual deceleration); (2) the CMEs studied here are still accelerating even after the flare maximum, so energy must be continuously fed into the CME even after the time of the maximum heating and radiation has elapsed in the corona; (3) the rapid deceleration, presumably due to interactions with the ambient medium, mainly occurs over a relatively short timescale following the acceleration phase; and (4) CME-CME interactions seem a common phenomenon close to solar maximum. Our comparison between different techniques (and data sets) has important implications for CME observations and their interpretations: (1) for the current cases, triangulation assuming a compact CME geometry is more reliable than triangulation assuming a spherical front attached to the Sun for distances below 50-70 solar radii from the Sun, but beyond about 100 solar radii we would trust the latter more; (2) a proper treatment of CME geometry must be performed in determining CME Sun-to-Earth kinematics, especially when the CME propagation direction is far away from the

Practical design considerations for photovoltaic power station

Science.gov (United States)

Swanson, T. D.

Aspects of photovoltaic (PV) technology are discussed along with generic PV design considerations, taking into account the resource sunlight, PV modules and their reliability, questions of PV system design, the support structure subsystem, and a power conditioning unit subsystem. A description is presented of two recent projects which demonstrate the translation of an idea into actual working PV systems. A privately financed project in Denton, Maryland, went on line in early December, 1982, and began providing power to the local utility grid. It represents the first intermediate size, grid-connected, privately financed power station in the U.S. Based on firm quotes, the actual cost of this system is about $13/W peak. The other project, called the PV Breeder, is an energy independent facility which utilizes solar power to make new solar cells. It is also the first large industrial structure completely powered by the sun.

CONCEPTUAL STEPS TOWARDS EXPLORING THE FUNDAMENTAL NATURE OF OUR SUN

Directory of Open Access Journals (Sweden)

Attila Grandpierre

2004-06-01

Full Text Available One of the basic questions of solar research is the nature of the Sun. We show here how the plasma nature of the Sun leads to the self-generation of solar activity. The release of magnetic, rotational, gravitational, nuclear energies and that of the gravity mode oscillations deviate from uniformity and spherical symmetry. Through instabilities they lead to the emergence of sporadic and localized regions like flux tubes, electric filaments, magnetic elements and high temperature regions. A systematic approach exploring the solar collective degrees of freedom, extending to ordering phenomena of the magnetic features related to Higgs fields, is presented. Handling solar activity as transformations of energies from one form to another one presents a picture on the network of the energy levels of the Sun, showing that the Sun is neither a mere "ball of gas" nor a "quiescent steady-state fusion-reactor machine", but a complex self-organizing system. Since complex self-organizing systems are similar to living systems (and, by some opinion, identical with them, we also consider what arguments indicate the living nature of the Sun. Thermodynamic characteristics of the inequilibrium Sun are found important in this respect and numerical estimations of free energy rate densities and specific exergies are derived.

100 billion suns

International Nuclear Information System (INIS)

Kippenhahn, R.

1983-01-01

A work on the world of astrophysics primarily for lay readers. The author writes only about the discoveries he ''experienced'' during the past 25 years (before 1979). Illustrated somewhat in color plus a set of superb colar plates. Contents, abridged: The long life of stars. The life story of the sun. The life story of massive stars. The end of stars. How stars are born. Planets and their inhabitants

Evaluation of the new ESR network software for the retrieval of direct sun products from CIMEL CE318 and PREDE POM01 sun-sky radiometers

Directory of Open Access Journals (Sweden)

V. Estellés

2012-12-01

Full Text Available The European Skynet Radiometers network (EuroSkyRad or ESR has been recently established as a research network of European PREDE sun-sky radiometers. Moreover, ESR is federated with SKYNET, an international network of PREDE sun-sky radiometers mostly present in East Asia. In contrast to SKYNET, the European network also integrates users of the CIMEL CE318 sky–sun photometer. Keeping instrumental duality in mind, a set of open source algorithms has been developed consisting of two modules for (1 the retrieval of direct sun products (aerosol optical depth, wavelength exponent and water vapor from the sun extinction measurements; and (2 the inversion of the sky radiance to derive other aerosol optical properties such as size distribution, single scattering albedo or refractive index. In this study we evaluate the ESR direct sun products in comparison with the AERosol RObotic NETwork (AERONET products. Specifically, we have applied the ESR algorithm to a CIMEL CE318 and PREDE POM simultaneously for a 4-yr database measured at the Burjassot site (Valencia, Spain, and compared the resultant products with the AERONET direct sun measurements obtained with the same CIMEL CE318 sky–sun photometer. The comparison shows that aerosol optical depth differences are mostly within the nominal uncertainty of 0.003 for a standard calibration instrument, and fall within the nominal AERONET uncertainty of 0.01–0.02 for a field instrument in the spectral range 340 to 1020 nm. In the cases of the Ångström exponent and the columnar water vapor, the differences are lower than 0.02 and 0.15 cm, respectively. Therefore, we present an open source code program that can be used with both CIMEL and PREDE sky radiometers and whose results are equivalent to AERONET and SKYNET retrievals.

Here comes the sun...; Here comes the sun...

Energy Technology Data Exchange (ETDEWEB)

Best, Robert [Centro de Investigacion en Energia (CIE) de la UNAM, Temixco, Morelos (Mexico)

2010-07-01

It sounds a bit strange that you can use solar energy to maintain or refrigerate products or spaces below the ambient temperature, because we know that something that makes the sun is heating; but yes indeed, the sun can produce cold, and in addition without polluting, and without consuming conventional energy. In this document are mentioned the various research projects on solar cooling that have been made in the Energy Research Center at the Universidad Nacional Autonoma de Mexico such as the thermo-chemical intermittent refrigerator, the geothermal cooling demonstration system in Mexicali, B.C., the GAX system for air conditioning, the ice producer intermittent solar refrigerator, the continuous solar refrigerator, the refrigeration by ejection-compression. It also mentions the functioning of heat pumps and the process of solar drying applications in agricultural products. [Spanish] Suena un poco extrano que se pueda utilizar la energia solar para mantener o refrigerar productos o espacios por debajo de la temperatura ambiente, ya que sabemos que algo que hace el sol es calentar; pero si, el sol puede producir frio, y ademas sin contaminar y sin consumir energia convencional. En este documento se mencionan las diferentes investigaciones sobre refrigeracion solar que se han realizado en el Centro de Investigacion en Energia de la Universidad Nacional Autonoma de Mexico como el refrigerador termoquimico intermitente, el sistema demostrativo de refrigeracion geotermico en Mexicali, B.C., el sistema GAX para aire acondicionado, el refrigerador solar intermitente productor de hielo, el refrigerador continuo solar, la refrigeracion por eyecto-compresion. Tambien se menciona el funcionamiento de las bombas de calor y el proceso de secado solar de aplicacion en productos agropecuarios.

Formulation of a topical sun protection cream for people with albinism

African Journals Online (AJOL)

The aim of this investigation was to design and develop a sun protection product for people with albinism that is affordable, applicable to their specific skin condition, and provide them with the maximum sun protection possible. To achieve the required Sun Protection Factor value of > 20, simple creams were combined with ...

Professional skippers' sun-protection knowledge and behavior in the tropics.

Science.gov (United States)

Rodriguez, Olivier; Bousser, Véronique; N'goala, Brigitte; Doloir, Anatole; Quist, Danièle; Derancourt, Christian

2013-01-01

A preliminary inquiry, conducted on Martinique Island, sought to determine professional skippers' sun-protection knowledge and behavior. Fifty-two skippers (mean age: 41 years) completed a questionnaire; 39 (75 %) had a simple sunburn over the last 6 months and 3 (6%) severe sunburn; 54 (64%) declared achieving sun protection by wearing clothes during >90% of the day. Only 17% had used sun protection >90% of the time. © 2013 International Society of Travel Medicine.

The Sun: the Earth light source

Science.gov (United States)

Berrilli, Francesco; Giovannelli, Luca; Del Moro, Dario; Piazzesi, Roberto; Catena, Liu` Maria; Amicucci, Giordano; Vittorio, Nicola

2015-04-01

We have implemented at Department of Physics of University of Rome Tor Vergata a project called "The Sun: the Earth light source". The project obtained the official endorsement from the IAU Executive Committee Working Group for the International Year of Light. The project, specifically designed for high school students, is focused on the "scientific" study of Sun light by means of a complete acquisition system based on "on the shelf" appropriately CMOS low-cost sensor with free control s/w and self-assembled telescopes. The project (hereafter stage) plan is based on a course of two weeks (60 hours in total). The course contains 20 hours of theoretical lectures, necessary to learn basics about Sun, optics, telescopes and image sensors, and 40 hours of laboratory. During the course, scientists and astronomers share with high schools students, work activities in real research laboratories. High schools teachers are intensely involved in the project. Their role is to share activities with university teachers and realize outreach actions in the home institutions. Simultaneously, they are introduced to innovative teaching methods and the project in this way is regarded as a professional development course. Sun light analysis and Sun-Earth connection through light are the main scientific topics of this project. The laboratory section of the stage is executed in two phases (weeks): First phase aims are the realization of a keplerian telescope and low-cost acquisition system. During this week students are introduced to astronomical techniques used to safety collect and acquire solar light; Second phase aims is the realization of a low-cost instrument to analyse sunlight extracting information about the solar spectrum, solar irradiance and Sun-Earth connection. The proposed stage has been already tested in Italy reached the fifth edition in 2014. Since 2010, the project has been a cornerstone outreach program of the University of Rome Tor Vergata, the Italian Ministry of

15 million degrees a journey to the centre of the Sun

CERN Document Server

Green, Lucie

2016-01-01

Light takes eight minutes to reach Earth from the surface of the Sun. But its journey within the Sun takes hundreds of thousands of years. What is going on in there? What are light and heat? How does the Sun produce them and how on earth did scientists discover this? In this astonishing and enlightening adventure, you'll travel millions of miles from inside the Sun to its surface and to Earth, where the light at the end of its journey is allowing you to read right now. You'll discover how the Sun works (including what it sounds like), the latest research in solar physics and how a solar storm could threaten everything we know. And you'll meet the groundbreaking scientists, including the author, who pieced this extraordinary story together.

Modelling the seasonal variation of vitamin D due to sun exposure.

Science.gov (United States)

Diffey, B L

2010-06-01

The current interest in vitamin D as a preventive agent in many chronic diseases has led to a reappraisal of adequate sun exposure. Yet just what constitutes adequacy remains to be clearly defined and validated. To do this requires an understanding of how behaviour outdoors during the year translates into seasonal changes in vitamin D status. To develop a model for estimating the changes in serum 25-hydroxyvitamin D [25(OH)D] levels as a consequence of sun exposure throughout the year. A novel mathematical model is described that incorporates the changes in serum 25(OH)D following a single, whole-body exposure to solar ultraviolet radiation with daily sun exposure in order to estimate the annual variation in serum 25(OH)D. The model yields results that agree closely with measured data from a large population-based study. Application of the model showed that current advice about 10-20 min of daily sun exposure during the summer months does little in the way of boosting overall 25(OH)D levels, while sufficient sun exposure that could achieve a worthwhile benefit would compromise skin health. There is little in the way of public health advice concerning the benefits of sun exposure that can be given as an effective means of maintaining adequate vitamin D levels throughout the year. Instead it would seem safer and more effective to fortify more foods with vitamin D and/or to consider the use of supplements during the winter months. Messages concerning sun exposure should remain focused on the detrimental effects of excessive sun exposure and should avoid giving specific advice on what might be 'optimal' sun exposure. © 2010 The Authors. Journal Compilation © 2010 British Association of Dermatologists.

Human eye and the sun hot and cold light

CERN Document Server

Vavilov, S I

1965-01-01

The Human Eye and the Sun, """"Hot"""" and """"Cold"""" Light is a translation from the Russian language and is a reproduction of texts from Volume IV of S.I. Vavilov, president of the U.S.S.R. Academy of Sciences. The book deals with theoretical and practical developments in lighting techniques. The text gives a brief introduction on the relationship of the human eye and the sun, describing the properties of light, of the sun, and of the human eye. The book describes hot (incandescence) and cold light (luminescence) as coming from different sources. These two types of light are compared. The

A Sun Path Observation System Based on Augment Reality and Mobile Learning

Directory of Open Access Journals (Sweden)

Wernhuar Tarng

2018-01-01

Full Text Available This study uses the augmented reality technology and sensor functions of GPS, electronic compass, and three-axis accelerometer on mobile devices to develop a Sun path observation system for applications in astronomy education. The orientation and elevation of the Sun can be calculated by the system according to the user’s location and local time to simulate the Sun path. When holding the mobile device toward the sky, the screen will show the virtual Sun at the same position as that of the real Sun. The user can record the Sun path and the data of observation date, time, longitude, and latitude using the celestial hemisphere and the pole shadow on the system. By setting different observation times and locations, it can be seen that the Sun path changes with seasons and latitudes. The system provides contextual awareness of the Sun path concepts, and it can convert the observation data into organized and meaningful astronomical knowledge to enable combination of situated learning with spatial cognition. The system can solve the problem of being not able to record the Sun path due to a bad weather or topographical restrictions, and therefore it is helpful for elementary students when conducting observations. A teaching experiment has been conducted to analyze the learning achievement of students after using the system, and the results show that it is more effective than traditional teaching aids. The questionnaire results also reveal that the system is easy to operate and useful in recording the Sun path data. Therefore, it is an effective tool for astronomy education in elementary schools.

The structure and evolution of the Sun

CERN Document Server

Severino, Giuseppe

2017-01-01

This book equips the reader with a coherent understanding of the structure of the Sun and its evolution and provides all the knowledge required to construct a simplified model of the Sun. The early chapters cover key aspects of basic physics and describe the Sun’s size, mass, luminosity, and temperature. Using a semi-empirical approach, the structure of the present Sun is then modeled in detail, layer by layer, proceeding from the photosphere to the convection zone, radiation zone, and core. Finally, all stages of the Sun’s evolution, from its formation to the end of its life, are carefully explained. The book is primarily intended for university students taking the initial steps in moving from physics to astrophysics. It includes worked exercises and problems to illustrate the concepts discussed, as well as additional problems for independent study. With the aim of helping the reader as much as possible, most of the mathematics required to use the book are provided in the text.

Sun behaviour and personal UVR exposure among Europeans on short term holidays

DEFF Research Database (Denmark)

Petersen, Bibi; Triguero-Mas, Margarita; Maier, Bernhard

2015-01-01

Solar ultraviolet radiation (UVR) is known to be the main cause of skin cancer, the incidence of which is rising with national differences across Europe. With this observation study we aimed to determine the impact of nationality on sun behaviour and personal UVR exposure on sun and ski holidays....... 25 Danish and 20 Spanish sun-seekers were observed during a sun holiday in Spain, and 26 Danish and 27 Austrian skiers were observed during a ski holiday in Austria. The participants recorded their location and clothing in diaries. Personal time-logged UVR data were recorded as standard erythema...... doses (SEDs) by an electronic UVR dosimeter worn on the wrist. Danish sun-seekers were outdoors for significantly longer, received significant higher percentages of ambient UVR, and received greater accumulated UVR doses than Spanish sun-seekers. Danish skiers were also outdoors for significantly longer...

Determination of the decameter wavelength spectrum of the quiet sun

International Nuclear Information System (INIS)

Erickson, W.C.; Gergely, T.E.; Kundu, M.R.; Mahoney, M.J.

1977-01-01

The Teepee Tee array of the Clark Lake Radio Observatory has been used to compare the flux of the Sun with that of the sidereal sources Tau A and Vir A at several frequencies in the range 109.0-19.0 MHz. Only the two central banks of the E-W arm of the array were used as elements of a phase switched interferometer so that the Sun could be observed as a point souce and compared directly to the sidereal sources. The Sun was still partially resolved however, and appropriate corrections for this effect were made. The observations were taken at times when the Sun and either Tau A or Vir A were at the same declination. The authors have therefore been able to derive the values for the solar flux, without having to resort to a gain vs zenith distance correction. The observations, combined with those available in the literature, allow an accurate derivation of the meter and decameter wavelength spectrum of the quiet Sun. (Auth.)

Low-Power Low-Noise CMOS Imager Design : In Micro-Digital Sun Sensor Application

NARCIS (Netherlands)

Xie, N.

2012-01-01

A digital sun sensor is superior to an analog sun sensor in aspects of resolution, albedo immunity, and integration. The proposed Micro-Digital Sun Sensor (µDSS) is an autonomous digital sun sensor which is implemented by means of a CMOS image sensor, which is named APS+. The µDSS is designed

What the Sun Has Taught Us About Basic Properties of Matter

Energy Technology Data Exchange (ETDEWEB)

Basu, Sarbani [Yale University

2012-03-07

The Sun is an immensely large object formed out of many tons of gas. Yet the Sun can help us learn about some of the basic properties of matter. The structure of the Sun is governed not only by macrophysics such as hydrostatic equilibrium, convective and radiative heat transport, but also by microphysics such as nuclear reaction rates and the equation of state of the material that forms the Sun. Knowledge of the detailed structure of the Sun can therefore help us constrain the basic properties of matter. Helioseismology, the study of solar pulsations, has given us the means to get a detailed picture of the solar interior. In this talk I shall discuss how helioseismology has allowed us to determine details of solar structure, and in turn allowing us to study basic properties of matter.

Sun position calculator (SPC) for Landsat imagery with geodetic latitudes

Science.gov (United States)

Seong, Jeong C.

2015-12-01

Landsat imagery comes with sun position information such as azimuth and sun elevation, but they are available only at the center of a scene. To aid in the use of Landsat imagery for various solar radiation applications such as topographic correction, solar power, urban heat island, agriculture, climate and vegetation, it is necessary to calculate the sun position information at every pixel. This research developed a PC application that creates sun position data layers in ArcGIS at every pixel in a Landsat scene. The SPC program is composed of two major routines - converting universal transverse Mercator (UTM) projection coordinates to geographic longitudes and latitudes, and calculating sun position information based on the Meeus' routine. For the latter, an innovative method was also implemented to account for the Earth's flattening on an ellipsoid. The Meeus routine implemented in this research showed about 0.2‧ of mean absolute difference from the National Renewable Energy Laboratory (NREL) Solar Position Algorithm (SPA) routine when solar zenith and azimuth angles were tested with every 30 min data at four city locations (Fairbanks, Atlanta, Sydney and Rio Grande) on June 30, 2014. The Meeus routine was about ten times faster than the SPA routine. Professionals who need the Sun's position information for Landsat imagery will benefit from the SPC application.

Sun and Shade leaves, SIF, and Photosynthetic Capacity

Science.gov (United States)

Berry, J. A.; Badgley, G.

2016-12-01

Recent advances in retrieval of solar induced chlorophyll fluorescence (SIF) have opened up new possibilities for remote sensing of canopy physiology and structure. To date most of the emphasis has been placed on SIF as an indicator of stress and photosynthetic capacity. However, it is clear that canopy structure can also have an influence. To this point, simulations of SIF in land surface models tend to under predict observed variation in SIF. Also, large, systematic differences in SIF from different canopy types seem to correlate well with the photosynthetic capacity of these canopies. SIF emissions from pampered crops can be several-fold that from evergreen, needle-leaf forests. Yet, these may have similar vegetation indices and absorb a similar fraction of incident PAR. SIF photons produced in a conifer canopy do have a lower probability of escaping its dense, clumped foliage. However, this does not explain the correlated differences in photosynthetic rate and SIF. It is useful, in this regard, to consider the separate contributions of sun and shade leaves to the SIF emitted by a canopy. Sun leaves tend to be displayed to intercept the direct solar beam, and these highly illuminated leaves are often visible from above the canopy. Sun leaves produce more SIF and a large fraction of it escapes. Therefore, the intensity of SIF may be a sensitive indicator of the partitioning of absorbed PAR to sun and shade leaves. Many models account tor the different photosynthetic capacity of sun and shade leaves in calculating canopy responses. However, the fraction of leaves in each category is usually parameterized by an assumed leaf angle distribution (e.g. spherical). In reality, the sun/shade fraction can vary over a wide range, and it has been difficult to measure. SIF and possibly near-IR reflectance of canopies can be used to specify this key parameter with obvious importance to understanding photosynthetic rate.

Sun Safety Knowledge, Attitudes, and Behaviors among Beachgoing Adolescents

Science.gov (United States)

Merten, Julie Williams; Higgins, Sue; Rowan, Alan; Pragle, Aimee

2014-01-01

Background: Skin cancer rates are rising and could be reduced with better sun protection behaviors. Adolescent exposure to ultraviolet (UV) radiation is damaging because it can lead to skin cancer. This descriptive study extends understanding of adolescent sun exposure attitudes, knowledge, and behaviors. Methods: A sample of 423 beachgoing…

How Can I Protect My Children from the Sun?

Science.gov (United States)

... sleeved shirts and long pants and skirts can provide protection from UV rays. Clothes made from tightly woven ... expected. Remember to plan ahead, and keep sun protection handy—in your car, bag, or child’s backpack. Sun Safety in Schools The Protect Your Students from Skin Cancer fact ...

PROPERTIES OF NEAR-SUN ASTEROIDS

Energy Technology Data Exchange (ETDEWEB)

Jewitt, David, E-mail: jewitt@ucla.edu [Department of Earth and Space Sciences and Department of Physics and Astronomy, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095-1567 (United States)

2013-05-15

Asteroids near the Sun can attain equilibrium temperatures sufficient to induce surface modification from thermal fracture, desiccation, and decomposition of hydrated silicates. We present optical observations of nine asteroids with perihelia <0.25 AU (sub-solar temperatures {>=}800 K) taken to search for evidence of thermal modification. We find that the broadband colors of these objects are diverse but statistically indistinguishable from those of planet-crossing asteroids having perihelia near 1 AU. Furthermore, images of these bodies taken away from perihelion show no evidence for on-going mass-loss (model-dependent limits {approx}<1 kg s{sup -1}) that might result from thermal disintegration of the surface. We conclude that, while thermal modification may be an important process in the decay of near-Sun asteroids and in the production of debris, our new data provide no evidence for it.

Micro technology based sun sensor

DEFF Research Database (Denmark)

Hales, Jan Harry; Pedersen, Martin; Fléron, René

2003-01-01

various payloads and platforms. The conventional and commercial actuators and attitude sensors are in most cases not suited for these satellites, which again lead to new design considerations. Another important property is the launch cost, which can be kept relatively low as a result of the concept....... This fact enables students to get hands-on experience with satellite systems design and project management. This paper describes the attitude control and determination system of a Danish student satellite (DTUsat), with main focus on the two-axis MOEMS sun sensor developed. On the magnetotorquer controlled...... DTUsat sun sensors are needed along with a magnetometer to obtain unambiguous attitude determination for the ACDS and the payloads - an electrodynamic tether and a camera. The accuracy needed was not obtainable by employing conventional attitude sensors. Hence a linear slit sensor was designed...

[Buddhist influences on Sun Simiao's precious prescriptions for emergency].

Science.gov (United States)

Zhu, J

1999-10-01

Living in a period when the Buddhism was quite flourishing, Sun had a close contact with the monk Dao Xuan, the founder of Nanshan Sect Buddhism. Sun's Quian jin fang adopted all schools including Buddhism, evidenced by the following 3 aspects: 1) Direct Buddhist influence, mainly on medical morality; 2) Indian medicine coming together with Buddhism, including the theory of "four - element theory", the conception of all matters are medicines, pills of all disorders, recipes, and keep - fit art. Buddhism acts as a carrier here; 3) the achievements of treatment for beriberi by monks. However, Buddhist influence was far inferior to Taoism as far as Sun's work is concerned.

Socio demographic and Psychological Correlates of Sun Protection Behaviors among Outdoor Workers: A Review

International Nuclear Information System (INIS)

Nahar, V. K.; Ford, M. A.; Bass, M. A.; Vice, M. A.; Hallam, J. S.

2013-01-01

Outdoor workers are at a higher risk for developing skin cancer due to their increased sun exposure. The primary objective of this review was to synthesize the current research literature that addresses socio demographic and psychological factors related to sun protection behaviors in outdoor workers. Two additional purposes were to provide an overview of sun exposure and describe sun protection behaviors of outdoor workers. To identify the studies for this review, a methodical search was performed in the Pub Med, Psycinfo, Medline, and Eric databases. Fifteen studies met the review criteria. Despite regular and prolonged sun exposure, many outdoor workers fail to engage in sufficient sun protection behaviors. Correlates of outdoor workers sun protection behaviors include being female, older age, being white, personal skin cancer history, time (hours/years) spent at work, sun safety training, perceived prioritization of sun protection, concern about sun exposure, workplace support, families expectations, and familial information giving. However, limited attention is given to designing theoretically grounded studies to identify factors to inform future research. There is a need to conduct research based on solid theoretical foundations that explains the relationships among the factors in this domain.

Protecting Yourself from Sun Exposure

Science.gov (United States)

Fast Facts Protecting Yourself from Sun Exposure Anyone working outdoors is exposed to the sun’s ultraviolet (UV) rays, even on cloudy ... nausea, and fatigue. In addition to the skin, eyes can become sunburned. Sunburned eyes become red, dry, ...

Day the sun went out

CERN Multimedia

2007-01-01

"A new british sci-fi movie envisages the death of the sun not in billions of years, but in decades. And, amazingly, the film's scientific adviser says this may not be so far from the truth..." (1/2 page)

Sun protection and low levels of vitamin D: are people concerned?

Science.gov (United States)

Janda, Monika; Kimlin, Michael; Whiteman, David; Aitken, Joanne; Neale, Rachel

2007-11-01

Recent reports on the association between low serum vitamin D and increased risk of cancer raised concerns about possible adverse effects of primary prevention strategies for skin cancer. To evaluate if these reports may influence peoples' sun protective behavior, knowledge, and attitudes to the impact of sun protection on vitamin D. Within a population-based survey in Queensland, Australia (5,611 participants, mean age 50.7 years (range 20-75); 48.2% men), agreement with the statement that sun protection may result in not having enough vitamin D as well as factors associated with agreement were assessed. Overall, 837 (15.0%) participants agreed that sun protection may result in not having enough vitamin D, 2,163 (38.7%) neither agreed nor disagreed, and 2,591 (46.3%) disagreed with this statement. Factors associated with agreement included older age, darker skin color, and attempt to develop a suntan within the past year. These results suggest that future sun protection campaigns may need to address the issue of vitamin D and present ways to achieve sufficient vitamin D levels without increasing sun exposure at least in countries with high UV radiation throughout the year.

Radio emission of the sun and planets

CERN Document Server

Zheleznyakov, V V

1970-01-01

International Series of Monographs in Natural Philosophy, Volume 25: Radio Emission of the Sun and Planets presents the origin of the radio emission of the planets. This book examines the outstanding triumphs achieved by radio astronomy of the solar system. Comprised of 10 chapters, this volume begins with an overview of the physical conditions in the upper layers of the Sun, the Moon, and the planets. This text then examines the three characteristics of radio emission, namely, the frequency spectrum, the polarization, and the angular spectrum. Other chapters consider the measurements of the i

A High Temperature Liquid Plasma Model of the Sun

Directory of Open Access Journals (Sweden)

Robitaille P.-M.

2007-01-01

Full Text Available In this work, a liquid model of the Sun is presented wherein the entire solar mass is viewed as a high density/high energy plasma. This model challenges our current understanding of the densities associated with the internal layers of the Sun, advocating a relatively constant density, almost independent of radial position. The incompressible nature of liquids is advanced to prevent solar collapse from gravitational forces. The liquid plasma model of the Sun is a non-equilibrium approach, where nuclear reactions occur throughout the solar mass. The primary means of addressing internal heat transfer are convection and conduction. As a result of the convective processes on the solar surface, the liquid model brings into question the established temperature of the solar photosphere by highlighting a violation of Kirchhoff’s law of thermal emission. Along these lines, the model also emphasizes that radiative emission is a surface phenomenon. Evidence that the Sun is a high density/high energy plasma is based on our knowledge of Planckian thermal emission and condensed matter, including the existence of pressure ionization and liquid metallic hydrogen at high temperatures and pressures. Prior to introducing the liquid plasma model, the historic and scientific justifications for the gaseous model of the Sun are reviewed and the gaseous equations of state are also discussed.

Neutrino spectroscopy can probe the dark matter content in the Sun.

Science.gov (United States)

Lopes, Ilídio; Silk, Joseph

2010-10-22

After being gravitationally captured, low-mass cold dark-matter particles (mass range from 5 to ~50 × 10(9) electron volts) are thought to drift to the center of the Sun and affect its internal structure. Solar neutrinos provide a way to probe the physical processes occurring in the Sun's core. Solar neutrino spectroscopy, in particular, is expected to measure the neutrino fluxes produced in nuclear reactions in the Sun. Here, we show how the presence of dark-matter particles inside the Sun will produce unique neutrino flux distributions in (7)Be-ν and (8)B-ν, as well as (13)N-ν, (15)O-ν, and (17)F-ν.

The 136 MHZ/400 MHz earth station antenna-noise temperature prediction program for RAE-B

Science.gov (United States)

Taylor, R. E.; Fee, J. J.; Chin, M.

1972-01-01

A simulation study was undertaken to determine the 136 MHz and 400 MHz noise temperature of the ground network antennas which will track the RAE-B satellite during data transmission periods. Since the noise temperature of the antenna effectively sets the signal-to-noise ratio of the received signal, a knowledge of SNR will be helpful in locating the optimum time windows for data transmission during low noise periods. Antenna noise temperatures will be predicted for selected earth-based ground stations which will support RAE-B. Telemetry data acquisition will be at 400 MHz; tracking support at 136 MHz will be provided by the Goddard Range and Range Rate (RARR) stations. The antenna-noise temperature predictions will include the effects of galactic-brightness temperature, the sun, and the brightest radio stars. Predictions will cover the ten-month period from March 1, 1973 to December 31, 1973.

The SunWise Policy Intervention for School-Based Sun Protection: A Pilot Study

Science.gov (United States)

Emmons, Karen M.; Geller, Alan C.; Viswanath, Vish; Rutsch, Linda; Zwirn, Jodie; Gorham, Sue; Puleo, Elaine

2008-01-01

Skin cancer is highly preventable, but clearly there is a critical need to focus on better ways to disseminate information about known skin cancer prevention. The U.S. Environmental Protection Agency's (EPA) SunWise Program is one channel for reaching children, teachers, and school nurses. In a pilot study designed to increase adoption of…

Joint ARM/GCSS/SPARC TWP-ICE CRM Intercomparison Study: Description, Preliminary Results, and Invitation to Participate

Science.gov (United States)

Fridlind, A. M.; Ackerman, A. S.; Allen, G.; Beringer, J.; Comstock, J. M.; Field, P. R.; Gallagher, M.; Hacker, J. M.; Hume, T.; Jakob, C.; Liu, G.; Long, C. N.; Mather, J. H.; May, P. T.; McCoy, R. F.; McFarlane, S. A.; McFarquhar, G. M.; Minnis, P.; Petch, J. C.; Schumacher, C.; Turner, D. D.; Whiteway, J. A.; Williams, C. R.; Williams, P. I.; Xie, S.; Zhang, M.

2008-12-01

The 2006 Tropical Warm Pool - International Cloud Experiment (TWP-ICE) is 'the first field program in the tropics that attempted to describe the evolution of tropical convection, including the large-scale heat, moisture, and momentum budgets at 3-hourly time resolution, while at the same time obtaining detailed observations of cloud properties and the impact of the clouds on the environment' [May et al., 2008]. A cloud- resolving model (CRM) intercomparison based on TWP-ICE is now being undertaken by the Atmospheric Radiation Measurement (ARM), GEWEX Cloud Systems Study (GCSS), and Stratospheric Processes And their Role in Climate (SPARC) programs. We summarize the 16-day case study and the wealth of data being used to provide initial and boundary conditions, and evaluate some preliminary findings in the context of existing theories of moisture evolution in the tropical tropopause layer (TTL). Overall, simulated cloud fields evolve realistically by many measures. Budgets indicate that simulated convective flux convergence of water vapor is always positive or near zero at TTL elevations, except locally at lower levels during the driest suppressed monsoon conditions, while simulated water vapor deposition to hydrometeors always exceeds sublimation on average at all TTL elevations over 24-hour timescales. The next largest water vapor budget term is generally the nudging required to keep domain averages consistent with observations, which is at least partly attributable to large-scale forcing terms that cannot be derived from measurements. We discuss the primary uncertainties.

Regular Biology Students Learn Like AP Students with SUN

Science.gov (United States)

Batiza, Ann; Luo, Wen; Zhang, Bo; Gruhl, Mary; Nelson, David; Hoelzer, Mark; Ning, Ling; Roberts, Marisa; Knopp, Jonathan; Harrington, Tom; LaFlamme, Donna; Haasch, Mary Anne; Vogt, Gina; Goodsell, David; Marcey, David

2016-01-01

The SUN approach to biological energy transfer education is fundamentally different from past practices that trace chemical and energy inputs and outputs. The SUN approach uses a hydrogen fuel cell to convince learners that electrons can move from one substance to another based on differential attraction. With a hydrogen fuel cell, learners can…

The Sun - From the star to domestic energy

International Nuclear Information System (INIS)

2009-06-01

Considered as a star and a deity, for a long period of time the Sun was thought to be another planet, whereas the word 'star' was reserved for all the brilliant points of light in the night sky. The Sun's status as a star in the sense of 'an astral body producing and emitting energy' was firmly established only at the beginning of the 20. century. Today astrophysicists are revealing more and more secrets of the fusion burning region located in its core. It is thanks to the Sun that life has appeared and evolved on Earth; it controls the cycle of 'For the last 4.6 million years the Sun has being providing us with light and heat. Today it is man's ambition to control this energy source'. The seasons and provides us with heat and light. But what exactly is the nature and origin of this prodigious energy source, with which man attempts to provide warmth and produce electricity? What is happening in this gigantic ball of fire, impossible to observe without protective glasses? And finally, how long will it continue to shine? Questions such as these took many centuries to be solved and will continue to be the subject of research for a long time to come. (authors)

Sun Tzu and the Art of Business Six Strategic Principles for Managers

CERN Document Server

McNeilly, Mark R

2011-01-01

More than two millennia ago the famous Chinese general Sun Tzu wrote the classic work on military strategy, The Art of War. Now, in a new edition of Sun Tzu and the Art of Business, Mark McNeilly shows how Sun Tzu's strategic principles can be applied to

Drift-free solar sail formations in elliptical Sun-synchronous orbits

Science.gov (United States)

Parsay, Khashayar; Schaub, Hanspeter

2017-10-01

To study the spatial and temporal variations of plasma in the highly dynamic environment of the magnetosphere, multiple spacecraft must fly in a formation. The objective for this study is to investigate the feasibility of solar sail formation flying in the Earth-centered, Sun-synchronous orbit regime. The focus of this effort is to enable formation flying for a group of solar sails that maintain a nominally fixed Sun-pointing attitude during formation flight, solely for the purpose of precessing their orbit apse lines Sun-synchronously. A fixed-attitude solar sail formation is motivated by the difficulties in the simultaneous control of orbit and attitude in flying solar sails. First, the secular rates of the orbital elements resulting from the effects of solar radiation pressure (SRP) are determined using averaging theory for a Sun-pointing attitude sail. These averaged rates are used to analytically derive the first-order necessary conditions for a drift-free solar sail formation in Sun-synchronous orbits, assuming a fixed Sun-pointing orientation for each sail in formation. The validity of the first-order necessary conditions are illustrated by designing quasi-periodic relative motions. Next, nonlinear programming is applied to design truly drift-free two-craft solar sail formations. Lastly, analytic expressions are derived to determine the long-term dynamics and sensitivity of the formation with respect to constant attitude errors, uncertainty in orbital elements, and uncertainty in a sail's characteristic acceleration.

A Sun Path Observation System Based on Augment Reality and Mobile Learning

OpenAIRE

Tarng, Wernhuar; Ou, Kuo-Liang; Lu, Yun-Chen; Shih, Yi-Syuan; Liou, Hsin-Hun

2018-01-01

This study uses the augmented reality technology and sensor functions of GPS, electronic compass, and three-axis accelerometer on mobile devices to develop a Sun path observation system for applications in astronomy education. The orientation and elevation of the Sun can be calculated by the system according to the user’s location and local time to simulate the Sun path. When holding the mobile device toward the sky, the screen will show the virtual Sun at the same position as that of the rea...

Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

International Nuclear Information System (INIS)

Blennow, Mattias; Edsjö, Joakim; Ohlsson, Tommy

2011-01-01

The prospects to detect neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes.

Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

International Nuclear Information System (INIS)

Blennow, Mattias; Edsjoe, Joakim; Ohlsson, Tommy

2006-01-01

The prospects for detecting neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes

Adoption of sun safe workplace practices by local governments.

Science.gov (United States)

Wallis, Allan; Andersen, Peter A; Buller, David B; Walkosz, Barbara; Lui, Lucia; Buller, Mary; Scott, Michael D; Jenkins, Rob

2014-01-01

Outdoor workers are especially susceptible to skin cancer--the most common, but also one of the most preventable, forms of cancer. Colorado, the location of the study, has the second highest rate of skin cancer deaths in the nation. Local government managers in Colorado-in municipalities, counties, and special districts-were surveyed to ascertain the extent to which they engage in formal (written) and informal practices to protect their outdoor workers against excessive exposure to sun. The survey consisted of 51 questions assessing awareness of formal or informal practices for sun protection of outdoor workers. An index of practices--the study's dependent variable--was created that was composed or practices such as providing employees free or reduced-cost sunscreen, wide-brimmed hats, sunglasses, long-sleeved work shirts, long work pants, and temporary or permanent outdoor shade shelters. Proscriptive policies, such as restricting the use of broad brimmed hats, were subtracted from the index. Surveys were completed by 825 administrators representing 98 jurisdictions. Responses from administrators in the same jurisdiction were averaged. More than 40% of responding jurisdictions indicated that they engaged in informal sun safety practices. Tests conducted to determine what variables might account for the adoption of these sun protection practices found that the degree to which a community could be regarded as cosmopolite and as having an individualistic political culture were significant predictors. Type of government was also significant. Although, higher community income was a significant predictor, neither local government budget nor size was significant. The adoption of sun safe practices bears low costs with potentially high returns. Findings from this study suggest that awareness campaigns might most effectively target cosmopolite communities, but that the greatest impact might be achieved by targeting localite communities. Government size and budget do not

Evidence for continuum absorption above the quiet sun transition region

International Nuclear Information System (INIS)

Schmahl, E.J.; Orrall, F.Q.

1979-01-01

We report new evidence for continuum absorption in the solar transition zone in EUV spectra obtained from OSO 4, OSO 6, ATM, and full Sun measurements. This absorption shortward of 912 A is manifest everywhere on the Sun's disk. It is present within network cells and boundaries of the quiet Sun, in coronal holes, in active regions, above the limb, and in solar prominences. Models of the upper chromosphere and the transition zone must be modified to include an admixture of neutral hydrogen (or possibly singly ionized helium) with the hotter plasma

The Iconography and Symbolism of Sun God in Urartian Art

Science.gov (United States)

Poghosyan, Gayane

2016-12-01

The predominating symbol of the winged sun disc in Urartian religious iconography testifies the significant role and importance of the sun in worship. The stylistic variation and peculiar iconographic features of the winged discs, sacred animals and divine images associated with solar deity shows the relationship between the cult of the sun god, sequence of the different phases of the year and constellations in Urartian culture. Such kind of iconography is possibly formed and stylized in result of interaction of ancient human imaginations, influence of rock paintings and religious beliefs.

Sun protection education for diverse audiences: need for skin cancer pictures

OpenAIRE

Guevara, Yanina; Gaber, Rikki; Clayman, Marla L.; Gordon, Elisa J.; Friedewald, John; Robinson, June K.

2015-01-01

Sun protection education is needed for kidney transplant recipients, whose increased risk of skin cancer could be ameliorated with sun protection. Cognitive interviews with 24 participants equally stratified among Non-Hispanic White, Non-Hispanic Black and Hispanic/Latino kidney transplant recipients were performed to evaluate a sun protection education workbook. Study participants were recruited over the phone using a registry of 700 kidney transplant recipients. Participants included 12 wom...

Sun following system adjustment at the UTFSM

International Nuclear Information System (INIS)

Georgiev, A.; Roth, P.; Olivares, A.

2004-01-01

The 'Evaluacion Solar' Laboratory of the Technical University Federico Santa Maria (UTFSM) in Valparaiso exists since 1957. Some types of sun following systems using instruments for different types of solar measurements were created during the mentioned period in this Laboratory. A solar tracking unit INTRA was recently installed in the UTFSM. It is considered a modern measuring and registering system for actual measuring of radiation in digital form, easier to store and to process. The action of the sun tracker is autonomous, which makes it a flexible tool to support direct radiation measurements. A special device was designed and constructed to support the measuring instruments. Three Eppley pyrheliometers were mounted on the unit and connected with an automatic registering system. An additional UV measuring sensor will be mounted soon. The realized measurements were compared with the results obtained manually from a K and Z pyrheliometer. The difference between both types of pyrheliometers is very small, which is a good precondition for using the INTRA sun tracker for precise measurements in the future

Escape of magnetic toroids from the Sun

International Nuclear Information System (INIS)

Bieber, John W.; Rust, David M.

1996-01-01

Analysis of heliospheric magnetic fields at 1 AU shows that 10 24 Mx of net toroidal flux escapes from the Sun per solar cycle. This rate is compared with the apparent rate of flux emergence at the solar surface, and it is concluded that escaping toroids will remove at least 20% of the emerging flux, and may remove as much as 100% of emerging flux if multiple eruptions occur on the toroids. The data imply that flux escapes the Sun with an efficiency far exceeding Parker's upper limit estimate of 3%. Toroidal flux escape is almost certainly the source of the observed overwinding of the interplanetary magnetic field spiral. Two mechanisms to facilitate net flux escape are discussed: helicity charging to push open the fields and flux transport with reconnection to close them off. We estimate the Sun will shed ∼2x10 45 Mx 2 of magnetic helicity per solar cycle, leading to a mean helicity density of 100 Mx 2 cm -3 at 1 AU, which agrees well with observations

IS THE POLAR REGION DIFFERENT FROM THE QUIET REGION OF THE SUN?

International Nuclear Information System (INIS)

Ito, Hiroaki; Shiota, Daikou; Tokumaru, Munetoshi; Fujiki, Ken'ichi; Tsuneta, Saku

2010-01-01

Observations of the polar region of the Sun are critically important for understanding the solar dynamo and the acceleration of solar wind. We carried out precise magnetic observations on both the north polar region and the quiet Sun at the east limb with the spectropolarimeter of the Solar Optical Telescope aboard Hinode to characterize the polar region with respect to the quiet Sun. The average area and the total magnetic flux of the kilo-Gauss magnetic concentrations in the polar region appear to be larger than those of the quiet Sun. The magnetic field vectors classified as vertical in the quiet Sun have symmetric histograms around zero in the strengths, showing balanced positive and negative fluxes, while the histogram in the north polar region is clearly asymmetric, showing a predominance of the negative polarity. The total magnetic flux of the polar region is larger than that of the quiet Sun. In contrast, the histogram of the horizontal magnetic fields is exactly the same for both the polar region and the quiet Sun. This is consistent with the idea that a local dynamo process is responsible for the horizontal magnetic fields. A high-resolution potential field extrapolation shows that the majority of magnetic field lines from the kG-patches in the polar region are open with a fanning-out structure very low in the atmosphere, while in the quiet Sun, almost all the field lines are closed.

Differential rotation of the Sun and the Maunder minimum of solar activity

International Nuclear Information System (INIS)

Ikhsanov, R.N.; Vitinskij, Yu.I.

1980-01-01

Nature of differential rotation of the Sun is discussed. Investigation of long term changes in differential rotation separately for two phase of 11 year cycle of the Sun activity is carried out. Data on heliographic coordinates for every day of all groups of the Sun spots for the years preceding the epoch of the minimum of the 11 year cycle and the Sun groups for the years of maximum from ''Greenwich Photoheliographic Results'' for 1875-1954 are used as initial material. It is shown that differential rotation of the Sun changes in time from one 11 year cycle of the Sun activity to another. This change is connected with the power of 11 year cycle. During the maximum phase of 11 year cycle differentiality of the rotation increases in the cycles where the cycle maximum is higher. Before the minimum of 11 year cycle rotation differentiability is lower in the cycles for which activity maximum is higher in the next 11 year cycle. Equatorial rate of the Sun rotation increases with the decrease in the cycle power when the maximum Wolf number is less than 110. The mentioned regularities took place both during Maunder minimum and before its beginning [ru

SUN family proteins Sun4p, Uth1p and Sim1p are secreted from Saccharomyces cerevisiae and produced dependently on oxygen level.

Directory of Open Access Journals (Sweden)

Evgeny Kuznetsov

Full Text Available The SUN family is comprised of proteins that are conserved among various yeasts and fungi, but that are absent in mammals and plants. Although the function(s of these proteins are mostly unknown, they have been linked to various, often unrelated cellular processes such as those connected to mitochondrial and cell wall functions. Here we show that three of the four Saccharomyces cerevisiae SUN family proteins, Uth1p, Sim1p and Sun4p, are efficiently secreted out of the cells in different growth phases and their production is affected by the level of oxygen. The Uth1p, Sim1p, Sun4p and Nca3p are mostly synthesized during the growth phase of both yeast liquid cultures and colonies. Culture transition to slow-growing or stationary phases is linked with a decreased cellular concentration of Sim1p and Sun4p and with their efficient release from the cells. In contrast, Uth1p is released mainly from growing cells. The synthesis of Uth1p and Sim1p, but not of Sun4p, is repressed by anoxia. All four proteins confer cell sensitivity to zymolyase. In addition, Uth1p affects cell sensitivity to compounds influencing cell wall composition and integrity (such as Calcofluor white and Congo red differently when growing on fermentative versus respiratory carbon sources. In contrast, Uth1p is essential for cell resistance to boric acids irrespective of carbon source. In summary, our novel findings support the hypothesis that SUN family proteins are involved in the remodeling of the yeast cell wall during the various phases of yeast culture development and under various environmental conditions. The finding that Uth1p is involved in cell sensitivity to boric acid, i.e. to a compound that is commonly used as an important antifungal in mycoses, opens up new possibilities of investigating the mechanisms of boric acid's action.

ID-1 mass storage system for mainframe by using FDDI network

International Nuclear Information System (INIS)

Morita, Y.; Fujii, H.; Inoue, E.; Kodama, H. Manabe, A.; Miyamoto, A.; Nomachi, M.; Watase, Y.; Yasu, Y.

1994-01-01

The authors have developed an ID-1 mass storage system as a distributed data server for Fujitsu mainframe computers. The system consists of a SONY ID-1 recorder DIR-1000, a tape robot system DMS-24 and a SCSI-II interface DFC-1500, which are connected to Spar Station 10 with an FDDI interface. The maximum speed of 7.5 Mbytes/sec is achieved for data transfer between Sparc Station 10 memory and DIR-1000 with a buffer size of 1 Mbytes. The system has been used successfully since last October to migrate more than 1 Tbytes data

ULYSSES comes full circle, before revisiting the Sun's poles

Science.gov (United States)

1998-04-01

From its unique perspective, Ulysses has provided scientists with the very first all-round map of the heliosphere, the huge bubble in space filled by the Sun's wind. The Earth swims deep inside the heliosphere, and gusts and shocks in the solar wind can harm satellites, power supplies and ommunications. They may also affect our planet's weather. A better grasp of the solar weather in the heliosphere is therefore one of the major aims of ESA's science programme. In a project of international cooperation between ESA and NASA, Ulysses was launched towards Jupiter in October 1990 by the US space shuttle Discovery. Arriving in February 1992, Ulysses stole energy from the giant planet in a slingshot manoeuvre and was propelled back towards the Sun in an elongated orbit almost at right angles to the ecliptic plane, where the Earth and other planets circle the Sun. "This month Ulysses returns to the point in space where its out-of-ecliptic journey began, but Jupiter isn't there," explains Richard Marsden, ESA's project scientist for Ulysses. "Following its own inexorable path around the Sun, Jupiter is far away on the opposite side of the Solar System. So Ulysses' course will not be changed a second time. The spacecraft is now in effect a man-made comet, forever bound into a 6-year polar orbit around the Sun." Ulysses now starts its second orbit. It will travel over the poles of the Sun in 2000-2001 just as the count of dark sunspots is expected to reach a maximum. With its operational life extended for the Ulysses Solar Maximum Mission, the spacecraft will find the heliosphere much stormier than during its first orbit. Discoveries so far Like its mythical namesake, Ulysses has already had an eventful voyage of discovery. Its unique trajectory has provided the scientific teams with a new perspective, from far out in space and especially in the previously unknown regions of the heliosphere over the Sun's poles. Passing within 9.8 degrees of the polar axis, the highly

Effects of multiple viewings of an ultraviolet photo on sun protection behaviors.

Science.gov (United States)

Mahler, H I M

2018-05-02

To determine whether multiple viewings of one's ultraviolet (UV) facial photo differentially affects subsequent sun protection behaviors relative to a single viewing. Pretest-posttest control group. Southern California college students (N = 151) were randomly assigned to be shown their UV facial photo one time, multiple times over the course of 2 weeks, or not at all. Emotional reactions, perceived susceptibility to skin damage, and sun protection intentions were assessed immediately, and sun protection behaviors were assessed during a surprise telephonic follow-up 1 month later. Immediately after viewing a UV photo of their face, participants reported significantly greater perceived susceptibility to skin damage, greater intentions to engage in future sun protection, and more negative emotions than those who had not seen a UV photo. Moreover, 1 month later, those who had viewed their UV photo were less likely to report having sunbathed and reported significantly greater sun protection than did controls. There were no differences in sun protection behaviors between those who had been shown their UV photo only once during the initial intervention session and those who had been sent their UV photo several times thereafter. However, among those who had been sent their UV photo several times, those who reported having viewed their photo on additional occasions reported significantly greater sun protection behaviors than those who had not. Being randomly assigned to view a UV facial photo multiple times generally neither strengthened nor weakened effects on subsequent sun protection behaviors relative to being shown the photo just once. However, among those who were sent their photo and thus had the option of viewing it more often than they had been assigned to, those who chose to view their photo more frequently also engaged in more sun protection behaviors. Copyright © 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Does the sun play a role in the aetiology of malignant melanoma ...

African Journals Online (AJOL)

The role of the sun in the aetiology of malignant melanoma is controversial. In 1992 Schuster1 wrote provocatively, 'Despite the lack of evidence of a causal link between sun exposure and melanoma, fear has been used shamelessly to frighten people out of the sun and into pigmented lesion clinics.' He claimed that the ...

Sun-Earth Day: Growth and Impact of NASA E/PO Program

Science.gov (United States)

Hawkins, I.; Thieman, J.

2004-12-01

Over the past six years, the NASA Sun-Earth Connection Education Forum has sponsored and coordinated education public outreach events to highlight NASA Sun-Earth Connection research and discoveries. Our strategy involves using celestial phenomena, such as total solar eclipses and the Transit of Venus to celebrate Sun-Earth Day, a popular Education and Public Outreach international program. Sun-Earth Day also focuses attention on Equinoxes and Solstices to engage K-12 schools and the general public in space science activities, demonstrations, and interactions with space scientists. In collaboration with partners that include the Exploratorium, Maryland Science Center, NASA Connect, Sun-Earth Connection missions, Ideum, and others, we produce webcasts, other multi-media, and print resources for use by school and informal educators nation-wide. We provide training and professional development to K-12 educators, museum personnel, amateur astronomers, Girl Scout leaders, etc., so they can implement their own outreach programs taking advantage of our resources. A coordinated approach promotes multiple programs occurring each year under a common theme. We will report lessons learned from several years of experience, and strategies for growth and sustainability. We will also share our plans for "Ancient Observatories - Timeless Knowledge" our theme for Sun-Earth Day 2005, which will feature solar alignments at ancient sites that mark the equinoxes and/or solstices. The video and webcast programming will feature several sites including: Chaco Canyon (New Mexico), Hovenweep (Utah), and Chichen Itza (Mexico). Many of these sites present unique opportunities to develop authentic cultural connections to Native Americans, highlighting the importance of the Sun across the ages.

Metabolic signature of sun exposed skin suggests catabolic pathway overweighs anabolic pathway.

Directory of Open Access Journals (Sweden)

Manpreet Randhawa

Full Text Available Skin chronically exposed to sun results in phenotypic changes referred as photoaging. This aspect of aging has been studied extensively through genomic and proteomic tools. Metabolites, the end product are generated as a result of biochemical reactions are often studied as a culmination of complex interplay of gene and protein expression. In this study, we focused exclusively on the metabolome to study effects from sun-exposed and sun-protected skin sites from 25 human subjects. We generated a highly accurate metabolomic signature for the skin that is exposed to sun. Biochemical pathway analysis from this data set showed that sun-exposed skin resides under high oxidative stress and the chains of reactions to produce these metabolites are inclined toward catabolism rather than anabolism. These catabolic activities persuade the skin cells to generate metabolites through the salvage pathway instead of de novo synthesis pathways. Metabolomic profile suggests catabolic pathways and reactive oxygen species operate in a feed forward fashion to alter the biology of sun exposed skin.

Previous climatic alterations are caused by the sun

International Nuclear Information System (INIS)

Groenaas, Sigbjoern

2003-01-01

The article surveys the scientific results of previous research into the contribution of the sun to climatic alterations. The author concludes that there is evidence of eight cold periods after the last ice age and that the alterations largely were due to climate effects from the sun. However, these effects are only causing a fraction of the registered global warming. It is assumed that the human activities are contributing to the rest of the greenhouse effect

Modelling Structural Flexure Effects in CPV Sun Trackers

OpenAIRE

Luque-Heredia, Ignacio; Quéméré, G.; Magalhães, P.H.; Fraile de Lerma, Alberto; Hermanns, Lutz Karl Heinz; Alarcón Álvarez, Enrique; Luque López, Antonio

2006-01-01

Nowadays CPV trends mostly based in lens parqueted flat modules, enable the separate design of the sun tracker. To enable this possibility a set of specifications is to be prescribed for the tracker design team, which take into account fundamental requisites such as the maximum service loads both permanent and variable, the sun tracking accuracy and the tracker structural stiffness required to maintain the CPV array acceptance angle loss below a certain threshold. In its first part this paper...

SunRISE Mission Concept Step 2 Study Status

Science.gov (United States)

Alibay, F.; Kasper, J. C.; Lazio, J.; Neilsen, T. L.

2017-12-01

We present an update on the Sun Radio Interferometer Space Experiment (SunRISE) mission concept, which was selected for a Step 2 study as part of the Small Explorer (SMEX) Mission of Opportunity (MoO) call. SunRISE is space-based sparse array, composed of six 6U CubeSats, designed to localize the radio emission associated with coronal mass ejections (CMEs) from the Sun. Radio emission from CMEs is a direct tracer of the particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Furthermore, CME radio emission is quite strong such that only a relatively small number of antennas is required, and a small mission would make a fundamental advancement. Indeed, the state-of-the-art for tracking CME radio emission is defined by single antennas (Wind/WAVES, Stereo/SWAVES) in which the tracking is accomplished by assuming a frequency-to-density mapping. This type of Heliophysics mission would be inherently cost prohibitive in a traditional spacecraft paradigm. However, the use of CubeSats, accompanied by the miniaturization of subsystem components, enables the development of this concept at lower cost than ever before. We present the most recent updates on this mission concept, starting from the concept's performance as compared to the required science and driving technical requirements. We then focus on the SunRISE mission concept of operations, which consists of six 6U CubeSats placed in a GEO graveyard orbit for 6 months to achieve the aforementioned science goals. The spacecraft fly in a passive formation, which allows them to form an interferometer while minimizing the impact on operations complexity. We also present details of the engineering design and the key trades being performed as part of the Step 2 concept study.

Sun safety knowledge and practice in UK postal delivery workers.

Science.gov (United States)

Houdmont, J; Davis, S; Griffiths, A

2016-06-01

Postal delivery workers spend a large proportion of their work time outdoors, placing them at increased risk of skin cancer. To date, no studies have examined occupational sun safety knowledge and practice within this group in the UK. To describe the occupational sun safety knowledge and practice of UK postal delivery workers and to investigate the association of demographic, personal and occupational factors with knowledge and practice in order to identify potential strategies for improving sun safety in this occupational group. Postal delivery workers completed a questionnaire that collected data on occupational sun safety knowledge and practice in addition to demographic, personal and workplace characteristics. One-way analysis of variances were applied to assess differences in knowledge and practice by these characteristics. A total of 1153 postal delivery workers completed the questionnaire, a 60% response rate. Thirty-three per cent reported receiving sun safety training within the previous 12 months. The majority of respondents reported correct knowledge on three of the six domains and good practice on four of the six behavioural domains. However, only one-fifth of respondents reported wearing sunglasses and ensuring a plentiful intake of water. Knowledge and practice differed significantly according to demographic, personal and workplace characteristics. There is a need to raise the profile of occupational skin cancer in this occupational group and to increase the priority given to occupational sun safety policies alongside targeted and tailored interventions, the effect of which can be evaluated. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine.

The Sun in Time

Science.gov (United States)

Adams, Mitzi L.; Sever, Thomas L.; Bero, Elizabeth

1998-01-01

Using a grant from NASA's Initiative to Develop Education through Astronomy and Space Science (IDEAS) program, we have developed an inter-disciplinary curriculum for middle-school students which targets both history and astronomy. Our curriculum explores the attitudes and techniques of ancient spiritual leaders, specifically those of the Maya and Inca cultures, who observed and tried to control the Sun. We wish students to understand the probable importance of astronomical observations to these ancient peoples. In addition, using the experience of an archaeologist, we show how modern techniques of viewing the Earth through satellite imagery, has allowed the re-discovery of ancient sites where solar observations and attempted manipulation of the universe took place. To contrast ancient observations of the Sun with modern ones, we use the experience of a solar astronomer and bring to the classroom up-to-date information about solar astronomy and the impact of solar activity on the Earth's environment. In this presentation, we will present fragments of our curriculum as well as results from pre- and post-tests given to participating groups of students. Finally, we will discuss comments from local middle-school teachers who were asked to evaluate our curriculum.

Spacecraft Attitude Determination with Earth Albedo Corrected Sun Sensor Measurements

DEFF Research Database (Denmark)

Bhanderi, Dan

-Method, Extended Kalman Filter, and Unscented Kalman Filter algorithms are presented and the results are compared. Combining the Unscented Kalman Filter with Earth albedo and enhanced Sun sensor modeling allows for three-axis attitude determination from Sun sensor only, which previously has been perceived...

The SPARC water vapor assessment II: intercomparison of satellite and ground-based microwave measurements

Science.gov (United States)

Nedoluha, Gerald E.; Kiefer, Michael; Lossow, Stefan; Gomez, R. Michael; Kämpfer, Niklaus; Lainer, Martin; Forkman, Peter; Christensen, Ole Martin; Oh, Jung Jin; Hartogh, Paul; Anderson, John; Bramstedt, Klaus; Dinelli, Bianca M.; Garcia-Comas, Maya; Hervig, Mark; Murtagh, Donal; Raspollini, Piera; Read, William G.; Rosenlof, Karen; Stiller, Gabriele P.; Walker, Kaley A.

2017-12-01

As part of the second SPARC (Stratosphere-troposphere Processes And their Role in Climate) water vapor assessment (WAVAS-II), we present measurements taken from or coincident with seven sites from which ground-based microwave instruments measure water vapor in the middle atmosphere. Six of the ground-based instruments are part of the Network for the Detection of Atmospheric Composition Change (NDACC) and provide datasets that can be used for drift and trend assessment. We compare measurements from these ground-based instruments with satellite datasets that have provided retrievals of water vapor in the lower mesosphere over extended periods since 1996. We first compare biases between the satellite and ground-based instruments from the upper stratosphere to the upper mesosphere. We then show a number of time series comparisons at 0.46 hPa, a level that is sensitive to changes in H2O and CH4 entering the stratosphere but, because almost all CH4 has been oxidized, is relatively insensitive to dynamical variations. Interannual variations and drifts are investigated with respect to both the Aura Microwave Limb Sounder (MLS; from 2004 onwards) and each instrument's climatological mean. We find that the variation in the interannual difference in the mean H2O measured by any two instruments is typically ˜ 1%. Most of the datasets start in or after 2004 and show annual increases in H2O of 0-1 % yr-1. In particular, MLS shows a trend of between 0.5 % yr-1 and 0.7 % yr-1 at the comparison sites. However, the two longest measurement datasets used here, with measurements back to 1996, show much smaller trends of +0.1 % yr-1 (at Mauna Loa, Hawaii) and -0.1 % yr-1 (at Lauder, New Zealand).

The SPARC water vapor assessment II: intercomparison of satellite and ground-based microwave measurements

Directory of Open Access Journals (Sweden)

G. E. Nedoluha

2017-12-01

Full Text Available As part of the second SPARC (Stratosphere–troposphere Processes And their Role in Climate water vapor assessment (WAVAS-II, we present measurements taken from or coincident with seven sites from which ground-based microwave instruments measure water vapor in the middle atmosphere. Six of the ground-based instruments are part of the Network for the Detection of Atmospheric Composition Change (NDACC and provide datasets that can be used for drift and trend assessment. We compare measurements from these ground-based instruments with satellite datasets that have provided retrievals of water vapor in the lower mesosphere over extended periods since 1996. We first compare biases between the satellite and ground-based instruments from the upper stratosphere to the upper mesosphere. We then show a number of time series comparisons at 0.46 hPa, a level that is sensitive to changes in H2O and CH4 entering the stratosphere but, because almost all CH4 has been oxidized, is relatively insensitive to dynamical variations. Interannual variations and drifts are investigated with respect to both the Aura Microwave Limb Sounder (MLS; from 2004 onwards and each instrument's climatological mean. We find that the variation in the interannual difference in the mean H2O measured by any two instruments is typically  ∼  1%. Most of the datasets start in or after 2004 and show annual increases in H2O of 0–1 % yr−1. In particular, MLS shows a trend of between 0.5 % yr−1 and 0.7 % yr−1 at the comparison sites. However, the two longest measurement datasets used here, with measurements back to 1996, show much smaller trends of +0.1 % yr−1 (at Mauna Loa, Hawaii and −0.1 % yr−1 (at Lauder, New Zealand.

Application of new control strategy for sun tracking

International Nuclear Information System (INIS)

Rubio, F.R.; Ortega, M.G.; Gordillo, F.; Lopez-Martinez, M.

2007-01-01

The application of high concentration solar cells technology allows a significant increase in the amount of energy collected by solar arrays per unit area. However, to make it possible, more severe specifications on the sun pointing error are required. In fact, the performance of solar cells with concentrators decreases drastically if this error is greater than a small value. These specifications are not fulfilled by simple tracking systems due to different sources of errors (e.g., small misalignments of the structure with respect to geographical north) that appear in practice in low cost, domestic applications. This paper presents a control application of a sun tracker that is able to follow the sun with high accuracy without the necessity of either a precise procedure of installation or recalibration. A hybrid tracking system that consists of a combination of open loop tracking strategies based on solar movement models and closed loop strategies using a dynamic feedback controller is presented. Energy saving factors are taken into account, which implies that, among other factors, the sun is not constantly tracked with the same accuracy, to prevent energy overconsumption by the motors. Simulation and experimental results with a low cost two axes solar tracker are exposed, including a comparison between a classical open loop tracking strategy and the proposed hybrid one

Sun protection and sunbathing practices among at-risk family members of patients with melanoma

Science.gov (United States)

2011-01-01

Background Despite the increased level of familial risk, research indicates that family members of patients with melanoma engage in relatively low levels of sun protection and high levels of sun exposure. The goal of this study was to evaluate a broad range of demographic, medical, psychological, knowledge, and social influence correlates of sun protection and sunbathing practices among first-degree relatives (FDRs) of melanoma patients and to determine if correlates of sun protection and sunbathing were unique. Methods We evaluated correlates of sun protection and sunbathing among FDRs of melanoma patients who were at increased disease risk due to low compliance with sun protection and skin surveillance behaviors. Participants (N = 545) completed a phone survey. Results FDRs who reported higher sun protection had a higher education level, lower benefits of sunbathing, greater sunscreen self-efficacy, greater concerns about photo-aging and greater sun protection norms. FDRs who reported higher sunbathing were younger, more likely to be female, endorsed fewer sunscreen barriers, perceived more benefits of sunbathing, had lower image norms for tanness, and endorsed higher sunbathing norms. Conclusion Interventions for family members at risk for melanoma might benefit from improving sun protection self-efficacy, reducing perceived sunbathing benefits, and targeting normative influences to sunbathe. PMID:21338483

Effect of smoking and sun drying on proximate composition of ...

African Journals Online (AJOL)

Effect of smoking and sun drying on proximate composition of Diplotaxodon fish species (Ndunduma) from lake Malawi, Malawi. ... African Journal of Food, Agriculture, Nutrition and Development ... The fish were washed then weighed and thereafter, smoked in a traditional smoking kiln and sun dried on reed mats.

Clothing reduces the sun protection factor of sunscreens

DEFF Research Database (Denmark)

Beyer, Ditte Maria; Faurschou, Annesofie; Haedersdal, M

2010-01-01

Individuals are recommended to wait for 20 min following sunscreen application before dressing. However, this is probably seldom done in daily life, and therefore we investigated how dressing earlier than 20 min after application affected the sun protection factor (SPF).......Individuals are recommended to wait for 20 min following sunscreen application before dressing. However, this is probably seldom done in daily life, and therefore we investigated how dressing earlier than 20 min after application affected the sun protection factor (SPF)....

New Parallel Algorithms for Structural Analysis and Design of Aerospace Structures

Science.gov (United States)

Nguyen, Duc T.

1998-01-01

Subspace and Lanczos iterations have been developed, well documented, and widely accepted as efficient methods for obtaining p-lowest eigen-pair solutions of large-scale, practical engineering problems. The focus of this paper is to incorporate recent developments in vectorized sparse technologies in conjunction with Subspace and Lanczos iterative algorithms for computational enhancements. Numerical performance, in terms of accuracy and efficiency of the proposed sparse strategies for Subspace and Lanczos algorithm, is demonstrated by solving for the lowest frequencies and mode shapes of structural problems on the IBM-R6000/590 and SunSparc 20 workstations.

Rotation curves of high-resolution LSB and SPARC galaxies with fuzzy and multistate (ultralight boson) scalar field dark matter

Science.gov (United States)

Bernal, T.; Fernández-Hernández, L. M.; Matos, T.; Rodríguez-Meza, M. A.

2018-04-01

Cold dark matter (CDM) has shown to be an excellent candidate for the dark matter (DM) of the Universe at large scales; however, it presents some challenges at the galactic level. The scalar field dark matter (SFDM), also called fuzzy, wave, Bose-Einstein condensate, or ultralight axion DM, is identical to CDM at cosmological scales but different at the galactic ones. SFDM forms core haloes, it has a natural cut-off in its matter power spectrum, and it predicts well-formed galaxies at high redshifts. In this work we reproduce the rotation curves of high-resolution low surface brightness (LSB) and SPARC galaxies with two SFDM profiles: (1) the soliton+NFW profile in the fuzzy DM (FDM) model, arising empirically from cosmological simulations of real, non-interacting scalar field (SF) at zero temperature, and (2) the multistate SFDM (mSFDM) profile, an exact solution to the Einstein-Klein-Gordon equations for a real, self-interacting SF, with finite temperature into the SF potential, introducing several quantum states as a realistic model for an SFDM halo. From the fits with the soliton+NFW profile, we obtained for the boson mass 0.212 motivated framework additional or alternative to the FDM profile.

Challenges to modeling the Sun-Earth System: A Workshop Summary

Science.gov (United States)

Spann, James F.

2006-01-01

This special issue of the Journal of' Atmospheric and Solar-Terrestrial Physics is a compilation of 23 papers presented at The 2004 Huntsville Modeling Workshop: Challenges to Modeling thc San-Earth System held in Huntsville, AB on October 18-22, 2004. The title of the workshop appropriately captures the theme of what was presented and discussed by the 120 participants. Currently, end-to-end modeling of the Sun-Earth system is a major goal of the National Space Weather and NASA living with a star (LWS) programs. While profound advances have been made in modeling isolated regions of the Sun-Earth system, minimal progress has been achieved in modeling the end-to-end system. The transfer of mass, energy and momentum through the coupled Sun-Earth system spans a wide range of scales inn time and space. The uncertainty in the underlying physics responsible for coupling contiguous regions of the Sun-Earth system is recognized as a significant barrier to progress

Electron beam irradiation of sun-dried apricots for quality maintenance

International Nuclear Information System (INIS)

Wei, Ming; Zhou, Linyan; Song, Hongbo; Yi, Jianyong; Wu, Bin; Li, Yaru; Zhang, Le; Che, Fengbin; Wang, Zhidong; Gao, Meixu

2014-01-01

The chemical, sensory, and microbial quality parameters of electron beam (EB)-irradiated and non-irradiated sun-dried apricots were periodically evaluated to optimize the EB irradiation of sun-dried apricots for quality maintenance. The sun-dried apricots were treated with 1.0, 2.0, 3.0, 4.0, and 5.0 kGy of EB and subsequently stored at ambient temperature. EB treatment at 1.0–3.0 kGy proved to be beneficial for retaining high levels of β-carotene, ascorbic acid, titratable acidity, total sugars, and color without any significant effect on sensory properties. Doses of 1.0–3.0 kGy retained the β-carotene content of sun-dried apricots to 8.21%, 9.27%, and 10.43% compared with 6.09% in control samples after 10 months of storage. After 10 months of storage, the maximum losses of ascorbic acid were 37.8% in control samples and 35.5% in 3.0 kGy-irradiated samples. Titratable acidity and total sugars were significantly enhanced immediately after 1.0–3.0 kGy irradiation treatment, and both parameters showed no significant change after 10 months of storage. Samples subjected to EB treatment at 3.0 kGy maintained a high overall acceptability of sun-dried apricots. Decreased number of viable microorganisms to below detection limits were observed after 3.0 kGy irradiation, and compared with the control, the logarithmic reductions after 10 months of storage were 0.98 for yeast and mold count, as well as 1.71 for bacterial count. - Highlights: • Electron beam irradiation was used for sun-dried apricots quality maintenance. • The chemical, sensory, and microbial quality parameters of apricots were evaluated. • 1.0–3.0 kGy proved to be beneficial for retaining high levels of apricots quality. • 3.0 kGy of irradiation maintained a high overall acceptability of sun-dried apricots. • 3.0 kGy of irradiation reduced the viable microorganisms to below detection limits

Self-Powered Sun Sensor Microsystems

NARCIS (Netherlands)

Wu, H.; Emadi, A.; Graaf, G. de; Leijtens, J.A.P.; Wolffenbuttel, R.F.

2009-01-01

An analog sun sensor has been designed based on shade profile proportional to the angle of incidence of incoming light projected onto a 2×2 array of photodiodes. This concept enables an autonomous self-powered optical system with two the main functions (electrical power generation for the amplifier

Challenges in Modeling the Sun-Earth System

Science.gov (United States)

Spann, James

2004-01-01

The transfer of mass, energy and momentum through the coupled Sun-Earth system spans a wide range of scales in time and space. While profound advances have been made in modeling isolated regions of the Sun-Earth system, minimal progress has been achieved in modeling the end-to-end system. Currently, end-to-end modeling of the Sun-Earth system is a major goal of the National Space Weather and NASA Living With a Star (LWS) programs. The uncertainty in the underlying physics responsible for coupling contiguous regions of the Sun-Earth system is recognized as a significant barrier to progress. Our limited understanding of the underlying coupling physics is illustrated by the following example questions: how does the propagation of a typical CME/solar flare influence the measured properties of the solar wind at 1 AU? How does the solar wind compel the dynamic response of the Earth's magnetosphere? How is variability in the ionosphere-thermosphere system coupled to magnetospheric variations? Why do these and related important questions remain unanswered? What are the primary problems that need to be resolved to enable significant progress in comprehensive modeling of the Sun-Earth system? Which model/technique improvements are required and what new data coverage is required to enable full model advances? This poster opens the discussion for how these and other important questions can be addressed. A workshop scheduled for October 8-22, 2004 in Huntsville, Alabama, will be a forum for identifying ana exploring promising new directions and approaches for characterizing and understanding the system. To focus the discussion, the workshop will emphasize the genesis, evolution, propagation and interaction of high-speed solar wind streamers or CME/flares with geospace and the subsequent response of geospace from its outer reaches in the magnetosphere to the lower edge of the ionosphere-mesosphere-thermosphere. Particular emphasis will be placed on modeling the coupling aspects

Sun light European Project

Science.gov (United States)

Soubielle, Marie-Laure

2015-04-01

2015 has been declared the year of light. Sunlight plays a major role in the world. From the sunbeams that heat our planet and feed our plants to the optical analysis of the sun or the modern use of sun particles in technologies, sunlight is everywhere and it is vital. This project aims to understand better the light of the Sun in a variety of fields. The experiments are carried out by students aged 15 to 20 in order to share their discoveries with Italian students from primary and secondary schools. The experiments will also be presented to a group of Danish students visiting our school in January. All experiments are carried out in English and involve teams of teachers. This project is 3 folds: part 1: Biological project = what are the mechanisms of photosynthesis? part 2: Optical project= what are the components of sunlight and how to use it? part 3: Technical project= how to use the energy of sunlight for modern devices? Photosynthesis project Biology and English Context:Photosynthesis is a process used by plants and other organisms to convert light energy, normally from the Sun, into chemical energy that can later fuel the organisms' activities. This chemical energy is stored in molecules which are synthesized from carbon dioxide and water. In most cases, oxygen is released as a waste product. Most plants perform photosynthesis. Photosynthesis maintains atmospheric oxygen levels and supplies all of the organic compounds and most of the energy necessary for life on Earth. Outcome: Our project consists in understanding the various steps of photosynthesis. Students will shoot a DVD of the experiments presenting the equipments required, the steps of the experiments and the results they have obtained for a better understanding of photosynthesis Digital pen project Electricity, Optics and English Context: Sunlight is a complex source of light based on white light that can be decomposed to explain light radiations or colours. This light is a precious source to create

Moon and Sun shadow observation with IceCube

Energy Technology Data Exchange (ETDEWEB)

Bos, Fabian; Tenholt, Frederik; Becker-Tjus, Julia [Theoretische Physik, Ruhr-Universitaet, Bochum (Germany); Westerhoff, Stefan [University of Wisconsin, Madison (United States); Collaboration: IceCube-Collaboration

2015-07-01

The analysis of the Moon shadow is a standard method in IceCube to determine the angular resolution and absolute pointing capabilities of the IceCube detector at the geographic South Pole. The Sun has not been used as a calibrator thus far, as its shadow is expected to be influenced by the solar magnetic field, which deflects the cosmic rays near the solar surface. This, on the other hand, provides indirect pieces of information on the magnetic field structure of the Sun. This talk shows a first analysis of the Sun shadow with IceCube data. The analysis is based on the data of the detector configurations with 79 (IC79) and 86 strings (IC86) from 2010 through 2012. To examine the shadows, a binned method is used to compare all events from one on-source with two off-source windows. For the IC40 and IC59 configuration a deficit with a statistical significance of more than 6σ was observed.

SunFast: A sun workstation based, fuel analysis scoping tool for pressurized water reactors

International Nuclear Information System (INIS)

Bohnhoff, W.J.

1991-05-01

The objective of this research was to develop a fuel cycle scoping program for light water reactors and implement the program on a workstation class computer. Nuclear fuel management problems are quite formidable due to the many fuel arrangement options available. Therefore, an engineer must perform multigroup diffusion calculations for a variety of different strategies in order to determine an optimum core reload. Standard fine mesh finite difference codes result in a considerable computational cost. A better approach is to build upon the proven reliability of currently available mainframe computer programs, and improve the engineering efficiency by taking advantage of the most useful characteristic of workstations: enhanced man/machine interaction. This dissertation contains a description of the methods and a user's guide for the interactive fuel cycle scoping program, SunFast. SunFast provides computational speed and accuracy of solution along with a synergetic coupling between the user and the machine. It should prove to be a valuable tool when extensive sets of similar calculations must be done at a low cost as is the case for assessing fuel management strategies. 40 refs

Sun, the Earth, and Near-Earth Space: A Guide to the Sun-Earth System

Science.gov (United States)

Eddy, John A.

2010-01-01

In a world of warmth and light and living things we soon forget that we are surrounded by a vast universe that is cold and dark and deadly dangerous, just beyond our door. On a starry night, when we look out into the darkness that lies around us, the view can be misleading in yet another way: for the brightness and sheer number of stars, and their chance groupings into familiar constellations, make them seem much nearer to each other, and to us, that in truth they are. And every one of them--each twinkling, like a diamond in the sky--is a white-hot sun, much like our own. The nearest stars in our own galaxy--the Milky Way-- are more than a million times further away from us than our star, the Sun. We could make a telephone call to the Moon and expect to wait but a few seconds between pieces of a conversation, or but a few hours in calling any planet in our solar system.

Learning about the Dynamic Sun through Sounds

Science.gov (United States)

Quinn, M.; Peticolas, L. M.; Luhmann, J.; MacCallum, J.

2008-06-01

Can we hear the Sun or its solar wind? Not in the sense that they make sound. But we can take the particle, magnetic field, electric field, and image data and turn it into sound to demonstrate what the data tells us. We present work on turning data from the two-satellite NASA mission called STEREO (Solar TErrestrial RElations Observatory) into sounds and music (sonification). STEREO has two satellites orbiting the Sun near Earth's orbit to study the coronal mass ejections (CMEs) from the Corona. One sonification project aims to inspire musicians, museum patrons, and the public to learn more about CMEs by downloading STEREO data and using it to make music. We demonstrate the software and discuss the way in which it was developed. A second project aims to produce a museum exhibit using STEREO imagery and sounds from STEREO data. We demonstrate a "walk across the Sun" created for this exhibit so people can hear the features on solar images. We show how pixel intensity translates into pitches from selectable scales with selectable musical scale size and octave locations. We also share our successes and lessons learned.

77 FR 36272 - SunShot Prize: America's Most Affordable Rooftop

Science.gov (United States)

2012-06-18

...The Department of Energy (DOE) announces in this notice the release of the SunShot Prize: America's Most Affordable Rooftop Solar for public comment. Interested persons are encouraged to learn about the SunShot Prize: America's Most Affordable Rooftop rules at eere.energy.gov/solar/sunshot/prize.html.

A low-power and high-precision miniaturized digital sun sensor

NARCIS (Netherlands)

Boer, B.M. de; Durkut, M.

2013-01-01

A prototype miniaturized digital sun sensor (miniDSS) was developed by TNO. It is expected to be launched on QuadSat for in-orbit demonstration. The single-chip sun sensor comprises an application specific integrated circuit (ASIC) on which an active pixel sensor (APS), read-out and processing

Sun Protection Motivational Stages and Behavior: Skin Cancer Risk Profiles

Science.gov (United States)

Pagoto, Sherry L.; McChargue, Dennis E.; Schneider, Kristin; Cook, Jessica Werth

2004-01-01

Objective: To create skin cancer risk profiles that could be used to predict sun protection among Midwest beachgoers. Method: Cluster analysis was used with study participants (N=239), who provided information about sun protection motivation and behavior, perceived risk, burn potential, and tan importance. Participants were clustered according to…

Use of social networking sites and associations with skin tone dissatisfaction, sun exposure, and sun protection in a sample of Australian adolescents.

Science.gov (United States)

Mingoia, John; Hutchinson, Amanda D; Gleaves, David H; Corsini, Nadia; Wilson, Carlene

2017-12-01

Previous research has indicated that greater exposure to traditional media (i.e. television, film, and print) predicted skin cancer risk factors in adolescents; however, the relationship between social media usage and these outcomes remains unexplored. We examined whether social networking site (SNS) usage, and the particular manner of this use, was associated with skin tone dissatisfaction, sun exposure and sun protection among Australian adolescents. We also explored sex differences in SNS usage related to tanning. A total of 1856 South Australian secondary school students completed the Australian School Students Alcohol and Drug 2014 survey. SNS usage related to tanning comprised posting pictures, posting text, viewing pictures, viewing text and liking or sharing posts. Adolescents spent 214.56 minutes, on average, per day using SNSs. Behaviours related to tanning that involved pictures (i.e. viewing pictures, posting pictures, and liking or sharing content) were significantly associated with more skin tone dissatisfaction, more sun exposure and less sun protection. Females performed all SNS-linked behaviours more frequently than did males, with the exception of posting text. Australian adolescents spend a considerable amount of time using SNSs, and their behaviours related to tanning on these SNSs are significantly associated with skin cancer risk factors.

Power producing sun shades; Elproducerende solafskaermninger

Energy Technology Data Exchange (ETDEWEB)

Johnsen, K.; Soerensen, Henrik; Katic, I.; Schmidt-Petersen, H.; AAroe, D.

2012-01-15

Integrating photovoltaics into sun shades takes advantage of the best opportunities to capture and utilize solar energy when the shades are most needed to shield users from solar radiation. The report describes results of a development project for solar shading in the form of broad, horizontal and rotating lamellae with solar cells and an integrated control function that simultaneously is optimized based on energy consumption and thermal and visual indoor climate. The project idea was to meet the needs for effective sun protection in the present office, commercial and public buildings, where glass facades are dominant. The conclusion of the development project is that it rarely would be optimal to integrate solar cells into movable shades. This will normally only be relevant in cases where it is justified by architectural considerations. (LN)

A Survey of Sun Protection Policy and Education in Secondary Schools

Science.gov (United States)

Buller, David B.; Buller, Mary Klein; Reynolds, Kim D.

2006-01-01

Background The Centers for Disease Control and Prevention (CDC) issued recommendations for school programs to reduce skin cancer. Objective Personnel at U.S. secondary schools were surveyed to describe sun protection policy and education prior to these recommendations. Methods School principals or other personnel at 484 secondary schools in 27 cities responded to a telephone survey in January and February 2002 (response rate = 31%). Results A sun protection policy was reported at 10% of the schools but sun protection education occurred at nearly all schools (96%). Policies were more prevalent in regions with high ultraviolet radiation (pprotection was a low policy priority for U.S. schools. Sun safety education was prevalent but written materials were used infrequently. A substantial proportion of school personnel were receptive to the CDC’s advice. PMID:16488293

High Energy Electron Signals from Dark Matter Annihilation in the Sun

Energy Technology Data Exchange (ETDEWEB)

Schuster, Philip; /SLAC; Toro, Natalia; /Stanford U., ITP; Weiner, Neal; Yavin, Itay; /New York U., CCPP

2012-04-09

In this paper we discuss two mechanisms by which high energy electrons resulting from dark matter annihilations in or near the Sun can arrive at the Earth. Specifically, electrons can escape the sun if DM annihilates into long-lived states, or if dark matter scatters inelastically, which would leave a halo of dark matter outside of the sun. Such a localized source of electrons may affect the spectra observed by experiments with narrower fields of view oriented towards the sun, such as ATIC, differently from those with larger fields of view such as Fermi. We suggest a simple test of these possibilities with existing Fermi data that is more sensitive than limits from final state radiation. If observed, such a signal will constitute an unequivocal signature of dark matter.

ULYSSES OBSERVATIONS OF THE MAGNETIC CONNECTIVITY BETWEEN CORONAL, MASS EJECTIONS AND THE SUN

Science.gov (United States)

Riley, Pete; Goslin, J. T.; Crooker, . U.

2004-01-01

We have investigated the magnetic connectivity of coronal mass ejections (CMEs) to the Sun using Ulysses observations of suprathermal electrons at various distances between 1 and 5.2 AU. Drawing on ideas concerning the eruption and evolution of CMEs, we had anticipated that there might be a tendency for CMEs to contain progressively more open field lines, as reconnection back at the Sun either opened or completely disconnected previously closed field lines threading the CMEs. Our results, however, did not yield any discernible trend. By combining the potential contribution of CMEs to the heliospheric flux with the observed buildup of flux during the course of the solar cycle, we also derive a lower limit for the reconnection rate of CMEs that is sufficient to avoid the "flux catastrophe" paradox. This rate is well below our threshold of detectability. Subject headings: solar wind - Sun: activity - Sun: corona - Sun: coronal mass ejections (CMEs) - On-line material: color figure Sun: magnetic fields

Prediction of the Sun-Glint Locations for the Communication, Ocean and Meteorological Satellite

Directory of Open Access Journals (Sweden)

Jae-Ik Park

2005-09-01

Full Text Available For the Communication, Ocean and Meteorological Satellite (COMS which will be launched in 2008, an algorithm for finding the precise location of the sun-glint point on the ocean surface is studied. The precise locations of the sun-glint are estimated by considering azimuth and elevation angles of Sun-satellite-Earth geometric position and the law of reflection. The obtained nonlinear equations are solved by using the Newton-Raphson method. As a result, when COMS is located at 116.2°E or 128.2°E longitude, the sun-glint covers region of ±10° (N-S latitude and 80-150° (E-W longitude. The diurnal path of the sun-glint in the southern hemisphere is curved towards the North Pole, and the path in the northern hemisphere is forwards the south pole. The algorithm presented in this paper can be applied to predict the precise location of sun-glint region in any other geostationary satellites.

UV Photography Shows Hidden Sun Damage

Science.gov (United States)

... mcat1=de12", ]; for (var c = 0; c UV photography shows hidden sun damage A UV photograph gives ... developing skin cancer and prematurely aged skin. Normal photography UV photography 18 months of age: This boy's ...

Automatic Hotspot and Sun Glint Detection in UAV Multispectral Images.

Science.gov (United States)

Ortega-Terol, Damian; Hernandez-Lopez, David; Ballesteros, Rocio; Gonzalez-Aguilera, Diego

2017-10-15

Last advances in sensors, photogrammetry and computer vision have led to high-automation levels of 3D reconstruction processes for generating dense models and multispectral orthoimages from Unmanned Aerial Vehicle (UAV) images. However, these cartographic products are sometimes blurred and degraded due to sun reflection effects which reduce the image contrast and colour fidelity in photogrammetry and the quality of radiometric values in remote sensing applications. This paper proposes an automatic approach for detecting sun reflections problems (hotspot and sun glint) in multispectral images acquired with an Unmanned Aerial Vehicle (UAV), based on a photogrammetric strategy included in a flight planning and control software developed by the authors. In particular, two main consequences are derived from the approach developed: (i) different areas of the images can be excluded since they contain sun reflection problems; (ii) the cartographic products obtained (e.g., digital terrain model, orthoimages) and the agronomical parameters computed (e.g., normalized vegetation index-NVDI) are improved since radiometric defects in pixels are not considered. Finally, an accuracy assessment was performed in order to analyse the error in the detection process, getting errors around 10 pixels for a ground sample distance (GSD) of 5 cm which is perfectly valid for agricultural applications. This error confirms that the precision in the detection of sun reflections can be guaranteed using this approach and the current low-cost UAV technology.

Differential Rotation in Sun-like Stars from Surface Variability and Asteroseismology

Science.gov (United States)

Nielsen, Martin Bo

2017-03-01

The Sun and other stars are known to oscillate. Through the study of small perturbations to the frequencies of these oscillations the rotation of the deep interior can be inferred. However, thus far the internal rotation of other Sun-like stars is unknown. The NASA Kepler mission has observed a multitude of Sun-like stars over a period of four years. This has provided high-quality photometric data that can be used to study the rotation of stars with two different techniques: asteroseismology and surface activity. Asteroseismology provides a means of measuring rotation in the stellar interior, while photometric variability from magnetically active regions are sensitive to rotation at the stellar surface. The combination of these two methods can be used to constrain the radial differential rotation in Sun-like stars. First, we developed an automated method for measuring the rotation of stars using surface variability. This method was initially applied to the entire Kepler catalog, out of which we detected signatures of rotation in 12,000 stars across the main sequence, providing robust estimates of the surface rotation rates and the associated errors. Second, we performed an asteroseismic analysis of six Sun-like stars, where we were able to measure the rotational splitting as a function of frequency in the p-mode envelope. This was done by dividing the oscillation spectrum into individual segments, and fitting a model independently to each segment. We found that the measured splittings were all consistent with a constant value, indicating little differential rotation. Third, we compared the asteroseismic rotation rates of five Sun-like stars to their surface rotation rates. We found that the values were in good agreement, again indicating little differential rotation between the regions where the two methods are most sensitive. Finally, we discuss how the surface rotation rates may be used as a prior on the seismic envelope rotation rate in a double-zone model

Diffusion time scales and accretion in the sun

International Nuclear Information System (INIS)

Michaud, G.

1977-01-01

It is thought that surface abundances in the Sun could be due largely to accretion either of comets or grains, and it has been suggested that if surface convection zones were smaller than is usually indicated by model calculations, accretion would be especially important. Unless the zone immediately below the surface convection zone is sufficiently stable for diffusion to be important, other transport processes, such as turbulence and meridional circulation, more efficient than diffusion, will tend to homogenise the Sun. Diffusion is the slowest of the transport processes and will become important when other transport processes become inoperative. Using diffusion theory the minimum mass of the convection zone can be determined in order that transport processes at the bottom of the zone are not to influence abundances in the convection zone. If diffusion time scales are shorter than the life of the star (Sun) diffusion will modify the abundances in the convection zone. The mass in the convection zone for which diffusion time scales are equal to the life of the star on the main sequence then determines the minimum mass in the convection zone that justifies neglect of transport processes at the bottom of the convection zone. It is calculated here that, for the Sun, this mass is between 3 x 10 -3 and 10 -2 solar mass, and a general explosion is derived for the diffusion time scale as a function of the mass of the convection zone. (U.K.)

Small-scale eruptive filaments on the quiet sun

International Nuclear Information System (INIS)

Hermans, L.M.; Martin, S.F.

1986-01-01

A study of a little known class of eruptive events on the quiet sun was conducted. All of 61 small-scale eruptive filamentary structures were identified in a systematic survey of 32 days of H alpha time-lapse films of the quiet sun acquired at Big Bear Solar Observatory. When fully developed, these structures have an average length of 15 arc seconds before eruption. They appear to be the small-scale analog of large-scale eruptive filaments observed against the disk. At the observed rate of 1.9 small-scale eruptive features per field of view per average 7.0 hour day, the rate of occurence of these events on the sun were estimated to be greater than 600 per 24 hour day.. The average duration of the eruptive phase was 26 minutes while the average lifetime from formation through eruption was 70 minutes. A majority of the small-scale filamentary sturctures were spatially related to cancelling magnetic features in line-of-sight photospheric magnetograms. Similar to large-scale filaments, the small-scale filamentary structures sometimes divided opposite polarity cancelling fragments but often had one or both ends terminating at a cancellation site. Their high numbers appear to reflect the much greater flux on the quiet sun. From their characteristics, evolution, and relationship to photospheric magnetic flux, it was concluded that the structures described are small-scale eruptive filaments and are a subset of all filaments

DETERMINING THE INITIAL HELIUM ABUNDANCE OF THE SUN

International Nuclear Information System (INIS)

Serenelli, Aldo M.; Basu, Sarbani

2010-01-01

We determine the dependence of the initial helium abundance and the present-day helium abundance in the convective envelope of solar models (Y ini and Y surf , respectively) on the parameters that are used to construct the models. We do so by using reference standard solar models (SSMs) to compute the power-law coefficients of the dependence of Y ini and Y surf on the input parameters. We use these dependencies to determine the correlation between Y ini and Y surf and use this correlation to eliminate uncertainties in Y ini from all solar model input parameters except the microscopic diffusion rate. We find an expression for Y ini that depends only on Y surf and the diffusion rate. By adopting the helioseismic determination of solar surface helium abundance, Y surf sun = 0.2485 ± 0.0035, and an uncertainty of 20% for the diffusion rate, we find that the initial solar helium abundance, Y ini sun , is 0.278 ± 0.006 independently of the reference SSMs (and particularly on the adopted solar abundances) used in the derivation of the correlation between Y ini and Y surf . When non-SSMs with extra mixing are used, then we derive Y ini sun = 0.273 ± 0.006. In both cases, the derived Y ini sun value is higher than that directly derived from solar model calibrations when the low-metallicity solar abundances (e.g., by Asplund et al.) are adopted in the models.

Effects of pricking, sun-drying and sieving on Ginger (Zingiber ...

African Journals Online (AJOL)

The effect of pricking, sun drying and sieving on the color retention of Nigerian yellow bark ginger were investigated. The exterior and interior surface of fresh, pricked and sun dried medium sized Nigerian ginger rhizomes (Tafin giwa) were analysed for colour variation. The colour values of the exterior surface of fresh ginger ...

Optimal sun-shading design for enhanced daylight illumination of subtropical classrooms

Energy Technology Data Exchange (ETDEWEB)

Ho, Ming-Chin [Architecture and Building Research Institute, MOI (China); Chiang, Che-Ming [Department of Architecture, National Cheng-Kung University, Tainan 701 (China); Chou, Po-Cheng [Department of Interior Design, Shu-Te University, No. 59 Hun-Shan Road, Yenchau 82445, Kaohsiung County (China); Chang, Kuei-Feng [Department of Real Estate Management, National Pingtung Institute of Commerce (China); Lee, Chia-Yen [Department of Mechanical and Automation Engineering, Da-Yeh University, Changhua 515 (China)

2008-07-01

This study investigates the feasibility of fitting windows with sun-shadings in order to minimize the lighting power costs in daylight-illuminated classrooms lit from a single side in subtropical regions. An IES-CPC model is created of a representative classroom in Taiwan, and a series of simulations is performed to determine the average illuminance value and the uniformity of the illuminance distribution in the classroom under various lighting conditions with no sun-shadings fitted to the window. The numerical results are found to be in good agreement with the experimental measurements obtained using an array of nine-channel photometers. Having confirmed the validity of the simulation scheme, the illumination properties of four different sun-shading designs are considered. The results show that a double-layered sun-shading represents the optimal sun-shading design in terms of achieving a uniform illumination distribution within the classroom. Given appropriate physical dimensions, this daylight access device achieves the minimum illuminance requirement of 500 lx and improves the lighting uniformity ratio from 0.25-0.35 to 0.40-0.42. Furthermore, using this sun-shading device, the required illuminance ratio of 0.5 can be obtained simply by switching on one of the three rows of lights in the classroom. Accordingly, the daylight access device not only improves the illuminance conditions within the classroom, but also reduces the lighting power cost by 71.5% compared to the case where all of the lights are turned on. (author)

Effect of sun radiation on the thermal behavior of distribution transformer

International Nuclear Information System (INIS)

Hajidavalloo, Ebrahim; Mohamadianfard, Mohamad

2010-01-01

Performance and life of oil-immersed distribution transformers are strongly dependent on the oil temperature. Transformers, working in regions with high temperature and high solar radiation, usually suffer from excessive heat in summers which results in their early failures. In this paper, the effect of sun radiation on the transformer was investigated by using experimental and analytical methods. Transformer oil temperature was measured in two different modes, with and without sun shield. Effects of different parameters such as direct and indirect solar radiation on the thermal behavior of the transformer were mathematically modeled and the results were compared with experimental findings. Agreements between the experimental and numerical results show that the model can reasonably predict thermal behavior of the transformer. It was found that a sun shield has an important effect on the oil temperature reduction in summer which could be as high as 7 deg. C depending on the load ratio. The amount of temperature reduction by sun shield reduces as the load ratio of transformer increases. By installing a sun shield and reducing oil temperature, transformer life could be increased up to 24% in average.

Electron microscopic investigation and elemental analysis of titanium dioxide in sun lotion.

Science.gov (United States)

Sysoltseva, M; Winterhalter, R; Wochnik, A S; Scheu, C; Fromme, H

2017-06-01

The objective of this research was to determine the size, shape and aggregation of titanium dioxide (TiO 2 ) particles which are used in sun lotion as UV-blocker. Overall, six sunscreens from various suppliers and two reference substances were analysed by electron microscopy (EM) techniques in combination with energy dispersive X-ray spectroscopy (EDS). Because of a high fat content in sun lotion, it was impossible to visualize the TiO 2 particles without previous EM sample preparation. Different defatting methods for TiO 2 from sun screens were tested. A novel sample preparation method was developed which allowed the characterization of TiO 2 particles with the help of EM and EDS. Aggregates of titanium dioxide with the size of primary particles varying between 15 and 40 nm were observed only in five products. In the sun lotion with the highest SPF, only few small aggregates were found. In the sun screen with the lowest SPF, the largest aggregates of TiO 2 particles were detected with sizes up to 1.6 μm. In one of the sun lotions, neither TiO 2 nor ZnO was found in spite of the labelling. Instead, approx. 500 nm large diamond-shaped particles were observed. These particles are composed of an organic material as only carbon was detected by EDS. A novel defatting method for sample preparation of titanium dioxide nanoparticles used in sun cosmetics was developed. This method was applied to six different sun lotions with SPF between 30 and 50+. TiO 2 particles were found in only five sunscreens. The sizes of the primary particles were below 100 nm and, according to the EU Cosmetic Regulation, have to be listed on the package with the term 'nano'. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

SO(2N) and SU(N) gauge theories

OpenAIRE

Lau, Richard; Teper, Michael

2013-01-01

We present our preliminary results of SO(2N) gauge theories, approaching the large-N limit. SO(2N) theories may help us to understand QCD at finite chemical potential since there is an orbifold equivalence between SO(2N) and SU(N) gauge theories at large-N and SO(2N) theories do not have the sign problem present in QCD. We consider the string tensions, mass spectra, and deconfinement temperatures in the SO(2N) pure gauge theories in 2+1 dimensions, comparing them to their corresponding SU(N) ...

The Sun's Mysteries from Space - I

Indian Academy of Sciences (India)

climate. Historically, it was the motion of the planets around the. Sun that .... concentrations of magnetic field, the convection is suppressed ... near-Earth space environments. ... Some of these reach our eyes and can be detected during the rare.

Micro-digital sun sensor: an imaging sensor for space applications

NARCIS (Netherlands)

Xie, N.; Theuwissen, A.J.P.; Büttgen, B.; Hakkesteegt, H.C.; Jasen, H.; Leijtens, J.A.P.

2010-01-01

Micro-Digital Sun Sensor is an attitude sensor which senses relative position of micro-satellites to the sun in space. It is composed of a solar cell power supply, a RF communication block and an imaging chip which is called APS+. The APS+ integrates a CMOS Active Pixel Sensor (APS) of 512×512

Culture and sun exposure in immigrant East Asian women living in Australia.

Science.gov (United States)

Jang, Haeyoung; Koo, Fung Kuen; Ke, Liang; Clemson, Lindy; Cant, Rosemary; Fraser, David R; Seibel, Marcus J; Tseng, Marilyn; Mpofu, Elias; Mason, Rebecca S; Brock, Kaye

2013-01-01

In this qualitative study, researchers examined cultural and attitudinal factors that might be related to sun-exposure behaviors among East Asian women living in Australia. Researchers asked Chinese (n = 20) and Korean (n = 16) immigrant women who participated in a larger cross-sectional quantitative study of vitamin D blood levels to volunteer to participate in an in-depth interview in 2010. These women reported a number of cultural factors related to their attitudes and behaviors with regard to sun exposure. They expressed preference for fair skin, a tradition of covering skin when outdoors, and no sunbathing culture. They believed that fair skin was more beautiful than tanned skin. They reported that beauty was the reason for active avoidance of sunlight exposure. Although they reported knowledge of the need for sun avoidance due to skin cancer risk, few reported knowledge about the benefits of sun exposure for adequate vitamin D levels. These findings may provide some reasons for vitamin D deficiency previously reported in these populations. Thus, researchers recommend that these attitudes of excessive sun protection and limiting sun exposure be further investigated as they may have implications for planning and delivery of health promotion programs to this growing population of immigrants in Australia.

Effects of pictures and textual arguments in sun protection public service announcements.