bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploring 30 years of malaria case data in KwaZulu‐Natal, South Africa: Part I. The impact of climatic factors
Authors: Craig M. H. , Kleinschmidt I. , Nawn J. B. , Le Sueur D. , Sharp B. L. 
Published: December 2004

SummaryLarge parts of Africa are prone to malaria epidemics. Advance epidemic warning would give health services an opportunity to prepare. Because malaria transmission is largely limited by climate, climate‐based epidemic warning systems are a real possibility. To develop and test such a system, good long‐term malaria and climate data are needed. In KwaZulu‐Natal (KZN), South Africa, 30 years of confirmed malaria case data provide a unique opportunity to examine short‐ and long‐term trends. We analysed seasonal case totals and seasonal changes in cases (both log‐transformed) against a range of climatic indicators obtained from three weather stations in the highest malaria incidence districts, using linear regression analysis. Seasonal changes in case numbers (delta log cases, dlc) were significantly associated with several climate variables. The two most significant ones were mean maximum daily temperatures from January to October of the preceding season (n = 30,r2 = 0.364,P = 0.0004) and total rainfall during the current summer months of November–March (n = 30,r2 = 0.282,P = 0.003). These two variables, when entered into the same regression model, together explained 49.7% of the total variation in dlc. We found no evidence of association between case totals and climate. In KZN, where malaria control operations are intense, climate appears to drive the interannual variation of malaria incidence, but not its overall level. The accompanying paper provides evidence that overall levels are associated with non‐climatic factors such as drug resistance and possibly HIV prevalence.
Fake antimalarials in Southeast Asia are a major impediment to malaria control: multinational cross‐sectional survey on the prevalence of fake antimalarials
Authors: Dondorp A. M. , Newton P. N. , Mayxay M. , Van Damme W. , Smithuis F. M. , Yeung S. , Petit A. , Lynam A. J. , Johnson A. , Hien T. T. , McGready R. , Farrar J. J. , Looareesuwan S. , Day N. P. J. , Green M. D. , White N. J. 
Published: December 2004

SummaryObjective  To assess the prevalence of counterfeit antimalarial drugs in Southeast (SE) Asia.Design  Cross‐sectional survey.Setting  Pharmacies and shops selling antimalarial drugs in Myanmar (Burma), Lao PDR, Vietnam, Cambodia and Thailand.Main outcome measures  Proportion of artemisinin derivatives or mefloquine containing drugs of substandard quality.Results  Of the 188 tablet packs purchased which were labelled as ‘artesunate’ 53% did not contain any artesunate. All counterfeit artesunate tablets were labelled as manufactured by ‘Guilin Pharma’, and refinements of the fake blisterpacks made them often hard to distinguish from their genuine counterparts. No other artemisinin derivatives were found to be counterfeited. Of the 44 mefloquine samples, 9% contained <10% of the expected amount of active ingredient.Conclusions  An alarmingly high proportion of antimalarial drugs bought in pharmacies and shops in mainland SE Asia are counterfeit, and the problem has increased significantly compared with our previous survey in 1999–2000. This is a serious threat to public health in the region.
Understanding of and attitudes to xenotransplantation: a survey among Italian university students
Authors: Bona Manuela De , Canova Daniele , Rumiati Rino , Russo Francesco Paolo , Ermani Mario , Ancona Ermanno , Naccarato Remo , Burra Patrizia 
Published: December 2004

Abstract: Xenotransplantation is currently at the experimental stages on animal models and many problems still have to be overcome in the biomedical, immunological and ethical fields. Moreover, people's attitudes to xenotransplantation vary: surveys among intensive‐care staff have revealed negative opinions, while the general public and students seem to be more positive. Little is known about the influence of schooling and the choice of university faculty on attitudes to xenotransplantation. The aims of this study were: (i) to evaluate university students’ attitudes to xenotransplantation; (ii) to investigate any socio‐demographic, religious and educational determinants behind students’ opinions on xenotransplantation. University undergraduates on five different courses were surveyed at Padua University. A 24‐item questionnaire was distributed to students at the end of lectures and completed anonymously immediately after its distribution. No information was given to students beforehand. Statistical analysis: chi‐squared, Pearson's test; P‐values <0.05 were considered significant. A total of 585 of 602 (97.2%) students completed the questionnaire (132 males, 453 females, mean age 20.4, range 19 to 43 yr). They were on courses in Medicine (33.85%), Agriculture (5.98%), Veterinary Medicine (11.45%), Psychology (18.46%) and Educational Sciences (30.26%). As for their previous schooling, they came from classical or scientific high school (58.3%), technical college (14.7%), language college (6.3%), teacher training college (11.9%) or others (8.8%). Concerning their religious beliefs, 83% were Catholics, and 56.2% defined themselves as practising Catholics. Eighty‐eight percentage of the students knew of the possibility of animal organs being transplanted into humans and 77.9% of them approved of this idea. When grouped according to gender and education, a higher proportion of students approving of xenotransplantation were male (P = 0.017) and had attended classical or scientific high school (P = 0.011). Disapproval for moral, ethical or religious reasons was higher among practising than among non‐practising Catholics; the latter rejected xenotransplantation more for immunological and infectious reasons (P = 0.014). As for the type of university course, a higher proportion of students approving of xenotransplantation attended science courses (Veterinary Medicine, Agriculture and Medicine vs. Educational Sciences and Psychology) (P = 0.013). University students generally approved of xenotransplantation. Male gender and a high‐school education were associated with a greater acceptance of xenotransplantation. Practising vs. non‐practising Catholics reported significantly different reasons for any disapproval of xenotransplantation. The choice of a science rather than an arts faculty at university was more strongly associated with a positive opinion on xenotransplantation.
Polymorphism of the human platelet antigen‐5 system is a risk factor for occlusive vascular complications in patients with sickle cell anemia
Authors: Castro V. , Alberto F. L. , Costa R. N. P. , Lepikson‐Neto J. , Gualandro S. F. M. , Figueiredo M. S. , Annichino‐Bizzacchi J. M. , Saad S. T. O. , Costa F. F. 
Published: December 2004

Background Polymorphisms of platelet membrane glycoproteins such as human platelet antigen (HPA)‐1b, HPA‐2b, the ‐5T/C Kozak sequence and C807T have been described as risk factors for vascular disease. Vaso‐occlusion episodes are a common feature of sickle cell anaemia (SCA), leading to complications such as stroke, acute chest syndrome, avascular head femur necrosis and priapism. Complex interactions are involved in vaso‐occlusion, and activated platelets may play an important role. These data raised the question of whether platelet polymorphisms could be implicated in occlusive vascular complications (OVC) of SCA.Materials and Methods In this study, 97 patients with SCA were analysed in two groups: 34 patients presenting with OVC (SCA‐VC) and 63 without these complications (SCA‐N). The distribution of the HPA‐1, ‐2 and ‐5 systems, as well as C807T dimorphism and ‐5T/C Kozak sequence alleles, was evaluated using DNA‐based methods.Results Patients of the SCA‐VC group showed a higher frequency of the HPA‐5b allele (0·324) compared with those of the SCA‐N group (0·111) (χ2 = 13·19,P = 0·0002). None of the other polymorphisms, isolated or associated as haplotypes, demonstrated any correlation with the development of OVC in these patients.Conclusions The findings of this study suggest that the HPA‐5b allele is a genetic risk factor for the development of OVC in patients with SCA. This allele could be explored as a target for the development of new therapeutic approaches.
LU21: a new high‐frequency antigen in the Lutheran blood group system
Authors: Crew V. Karamatic , Poole J. , Banks J. , Reed M. , Daniels G. 
Published: December 2004

Background and Objectives  The Lutheran blood group system comprises 18 antigens numbered LU1 to LU20, with two numbers obsolete. Thirteen antigens are of high frequency.Materials and Methods  Serological tests were performed by conventional methods. The monoclonal antibody‐specific immobilization of erythrocyte antigens (MAIEA) assay was carried out with monoclonal antibodies to Lutheran glycoprotein. All exons of the LU gene were amplified by the polymerase chain reaction (PCR) and directly sequenced from genomic DNA.Results  A patient was found to have an antibody to a high‐frequency red cell antigen during her second pregnancy. The antibody was shown to be Lutheran‐related and was distinguished from all reported Lutheran antibodies. MAIEA suggested the antibody was defining a novel epitope in domain 1 of the Lu‐glycoprotein. Sequencing of the LU gene revealed a new homozygous single‐point mutation, C282G, in exon 3, encoding an Asp94Glu change in the first domain of the Lu‐glycoprotein.Conclusions  The antibody detected a new high‐frequency Lutheran antigen, numbered LU21, that appears to result from an Asp94Glu substitution in the first, N‐terminal domain of the Lu‐glycoprotein.
External quality assessment for the detection of blood‐borne viruses in plasma by nucleic acid amplification technology: the first human immunodeficiency virus and hepatitis B virus studies (HIV EQA/1 and HBV EQA/1) and the fifth hepatitis C virus study (HCV EQA/5)
Authors: Pisani G. , Cristiano K. , Saldanha J. , Wirz M. , Bisso G. M. , Mele C. , Gentili G. ,   the EQA Participants
Published: December 2004

Background and Objectives  This External Quality Assessment (EQA) study was aimed at assessing the proficiency of blood centres and blood product manufacturers in detecting, by nucleic acid amplification technology (NAT), the possible contamination of plasma with hepatitis C virus (HCV), human immunodeficiency virus (HIV) and hepatitis B virus (HBV).Materials and Methods  Three independent panels, one for each virus, were prepared at the Istituto Superiore di Sanità (ISS) by diluting the respective reference preparations. NAT methods used by the EQA participants included polymerase chain reaction (PCR) assays by Roche, transcription‐mediated amplification (TMA) assays by Chiron and in‐house PCR assays.Results  Forty‐three of the 45 participants (95·6%) in the HCV EQA/5 who used a validated method were consistently able to detect a nominal concentration of 100 IU/ml for all six major genotypes. In the case of the HIV EQA/1, all 35 participants detected the samples containing 1000 IU/ml HIV, while five (14·3%) did not identify the samples containing 100 IU/ml HIV. With respect to the HBV EQA/1, all 16 participants correctly identified the positive samples containing either 1000 IU/ml or 100 IU/ml HBV. No false‐positive results were observed with any of the three panels.Conclusions  The HCV EQA/5 showed an improved proficiency of laboratories as compared with the HCV EQA/4. In fact, HCV genotypes 1, 2, 3 and 5 were correctly identified in 100% of the assays and genotypes 4 and 6 in 97·8% of the assays. While most of the participants in the HIV EQA/1 showed a good level of proficiency, an excellent performance was shown by all participants in the HBV EQA/1.
Pathogen reduction of buffy coat platelet concentrates using riboflavin and light: comparisons with pathogen‐reduction technology‐treated apheresis platelet products
Authors: Li J. , De Korte D. , Woolum M. D. , Ruane P. H. , Keil S. D. , Lockerbie O. , McLean R. , Goodrich R. P. 
Published: December 2004

Background and Objectives  A pathogen‐reduction technology (PRT) system using riboflavin and light has been developed for the treatment of platelet concentrates (PC) obtained by either buffy coat preparation (BCPC) or apheresis procedures (APPC). The aim of this study was to evaluate the effects of the treatment process on in vitro cell quality and on riboflavin conversion in PC.Materials and Methods  BCPC were prepared with the Compomat G4™ from whole blood which had been stored overnight after collection. APPC were obtained using the TRIMA™ apheresis procedure. Both PC products had been stored for 18–24 h prior to PRT treatment. BCPC and APPC were treated with PRT on day 2 and day 1 of shelf‐life, respectively. The treated PCs were then maintained for an additional 5 days after the PRT treatment. A panel of cell quality assays and high‐performance liquid chromatography (HPLC) analysis were performed.Results  Cell counts and plasma lactate dehydrogenase (LDH) levels during storage indicated that PRT did not induce significant cell lysis. Acceleration of a decrease in glucose and an increase in lactate was observed for treated PCs, but no significant differences were observed between treated BCPC and APPC. The pH of treated samples remained above 7·0, although was lower than that of the control. Platelet morphology of BCPC and APPC was well preserved. P‐selectin expression indicated significant platelet activation when compared with control PC (BCPC on day 6: 39% vs. 12%; APPC on day 5: 35% vs. 18%). Both P‐selectin expression and microparticle formation were not significantly different between treated BCPC and APPC during storage. The JC‐1 assay also displayed no loss of mitochondria integrity during the storage of treated products. Approximately 20% of riboflavin converted into photoproducts, including lumichrome.Conclusions  PRT treatment had an effect on the development of the normal platelet storage lesion at a level which seems tolerable for clinical usage.
Concurrent and Across Time Prediction of Young Adolescents’ Social Functioning: The Role of Emotionality and Regulation
Authors: Murphy Bridget C. , Shepard Stephanie A. , Eisenberg Nancy , Fabes Richard A. 
Published: December 2004

AbstractThe social functioning of 64 young adolescents (10‐ to 12‐year olds) was examined in relation to negative emotionality and regulation during early adolescence, as well as two, four, and six years earlier. Young adolescents who were viewed as relatively high in social functioning (i.e., high teacher‐rated school social competence; low mother‐ or father‐rated problem behavior) were generally viewed as relatively low on negative emotionality and high on regulatory abilities during early adolescence as well as two, four, and six years earlier. Furthermore, negative emotionality and regulation during early adolescence, and in some cases at previous time periods, contributed unique variance to the prediction of social functioning during early adolescence. Young adolescents who were consistently low in social functioning across time were higher on negative emotionality and lower on regulation than were young adolescents who were consistently high on social functioning over time.
A Semiparametric Multilevel Survival Model
Authors: Zhang Wenyang , Steele Fiona 
Published: December 2004

SummaryWe propose a semiparametric multilevel survival model for clustered duration data in which the effect of a continuous covariate is represented by an unspecified, possibly non-linear, function. This model makes no distributional assumption about the cluster level random effects. The performance of the method is assessed via Monte Carlo simulations. The model is applied in an analysis of first-birth intervals in Bangladesh to examine period effects in the timing of first births, while allowing for clustering within communities; the analysis reveals a non-linear trend in the first-birth interval over time.
Estimating Catch at Age from Market Sampling Data by Using a Bayesian Hierarchical Model
Authors: Hirst David , Aanes Sondre , Storvik Geir , Huseby Ragnar Bang , Tvete Ingunn Fride 
Published: December 2004

SummaryThe paper develops a Bayesian hierarchical model for estimating the catch at age of cod landed in Norway. The model includes covariate effects such as season and gear, and can also account for the within-boat correlation. The hierarchical structure allows us to account properly for the uncertainty in the estimates.
Period Analysis of Variable Stars by Robust Smoothing
Authors: Oh Hee-Seok , Nychka Doug , Brown Tim , Charbonneau Paul 
Published: December 2004

SummaryThe objective is to estimate the period and the light curve (or periodic function) of a variable star. Previously, several methods have been proposed to estimate the period of a variable star, but they are inaccurate especially when a data set contains outliers. We use a smoothing spline regression to estimate the light curve given a period and then find the period which minimizes the generalized cross-validation (GCV). The GCV method works well, matching an intensive visual examination of a few hundred stars, but the GCV score is still sensitive to outliers. Handling outliers in an automatic way is important when this method is applied in a ‘data mining’ context to a vary large star survey. Therefore, we suggest a robust method which minimizes a robust cross-validation criterion induced by a robust smoothing spline regression. Once the period has been determined, a nonparametric method is used to estimate the light curve. A real example and a simulation study suggest that the robust cross-validation and GCV methods are superior to existing methods.
Chebyshev’s Inequality for Nonparametric Testing with SmallNandαin Microarray Research
Authors: Beasley T. Mark , Page Grier P. , Brand Jaap P. L. , Gadbury Gary L. , Mountz John D. , Allison David B. 
Published: December 2004

SummaryMicroarrays are a powerful new technology that allow for the measurement of the expression of thousands of genes simultaneously. Owing to relatively high costs, sample sizes tend to be quite small. If investigators apply a correction for multiple testing, a very small p-value will be required to declare significance. We use modifications to Chebyshev’s inequality to develop a testing procedure that is nonparametric and yields p-values on the interval [0, 1]. We evaluate its properties via simulation and show that it both holds the type I error rate below nominal levels in almost all conditions and can yield p-values denoting significance even with very small sample sizes and stringent corrections for multiple testing.
Bayesian Analysis of Discrete Time Warranty Data
Authors: Stephens David , Crowder Martin 
Published: December 2004

SummaryThe analysis of warranty claim data, and their use for prediction, has been a topic of active research in recent years. Field data comprising numbers of units returned under guarantee are examined, covering both situations in which the ages of the failed units are known and in which they are not. The latter case poses particular computational problems for likelihood-based methods because of the large number of feasible failure patterns that must be included as contributions to the likelihood function. For prediction of future warranty exposure, which is of central concern to the manufacturer, the Bayesian approach is adopted. For this, Markov chain Monte Carlo methodology is developed.
ESTIMATION OF HOURLY AVERAGE SOLAR RADIATION ON TILTED SURFACE VIA ANNs
Authors: GAZELA MYRSINI , TAMBOURATZIS TATIANA 
Published: December 2004

An innovative approach is proposed for the estimation of hourly average solar radiation on tilted surface. The proposed approach, which is based on artificial neural networks and problem decomposition, demonstrates the following characteristics: • Accuracy. Superior estimation is attained over both conventional approaches and theoretical models. • Simplicity and efficiency. A small training set is employed and the training/test patterns involve few easily obtainable parameters. • Generalization capability and robustness to noise. Apart from being of interest in meteorology, the accurate and efficient estimation of hourly average solar radiation on tilted surface is especially important in solar energy applications.
Structural characterization of non‐oxide Chalcogenide Glasses using solid state NMR
Authors: Eckert Hellmut 
Published: December 2004

AbstractIn spite of the long‐standing importance of non‐oxide chalcogenide glasses in infrared optics and semiconductor technology, concepts describing the structural principles governing glass formation in these systems are just emerging. Most recently, modern quantitative solid state NMR techniques have offered new unique insights into the structural organization of these systems. In this review, we discuss the basic principles of various experimental approaches and their application to boron‐silicon,‐ and phosphorus chalcogenide glasses.
15N CPMAS NMR study of the structure and reactions of phthalocyaninatopolysiloxane and its precursors in the solid state
Authors: Wehrle Bernd , Zipplies Tilman , Limbach Hans‐Heinrich , Hanack Michael 
Published: December 2004

The high conductivities of the iodine‐doped title compound (see figure) and its germanium analogue have attracted considerable interest. Structural analysis by X‐ ray crystallography has not been possible, and solid state 13C NMR has yielded complex spectra which are often difficult to assign. I5N CPMAS NMR spectroscopy of I5N enriched samples provides a powerful ity of these species. tool for the study of the structure and reactivity of these species. magnified image
Passivation of metals by coating with polyaniline: Corrosion potential shift and morphological changes
Authors: Wessling Berhard 
Published: December 2004

Corrosion protection of metals can be obtained by coating them with polyaniline dispersions, resulting in a signifiecant and reproducible shift of the corrosion potential. Scanning electron micrograph indicate that the passivation is a multistep process, beginning with an etching stage in wh8ch grain boundaries become visible (see Figure). In the second step the metal surface is coated—non‐electrochemically—with an oxide layer. The exact mechanism of formation of this layer remains to be explored. magnified image
Photochemical synthesis of polyacrylate–silica hybrid sol–gel materials catalyzed by photoacids
Authors: Wei Yen , Wang Wei , Yeh Jui‐Ming , Wang Bin , Yang Dachuan , Murray James K. 
Published: December 2004

Photochemical synthesis of hybrid sol–gel materials is demonstrated for the first time. Photoacid‐catalyzed sol–gel reactions of tetraethyl orthosilicate with polymer precursors under ultraviolet radiation produce poly‐acrylate‐silica materials (shown schematically in the Figure). The effect of the concentrations of the photoacids and polymer precursors and the intensity of the radiation is discussed. magnified image
Recrystallization of electrodeposited copper indium diselenide thin films in an atmosphere of elemental selenium
Authors: Guillemoles Jean François , Lusson Alain , Cowache Pierre , Massaccesi Sylvie , Vedel Jacques , Lincot Daniel 
Published: December 2004

One use of copper indium dis‐ elenide (CIS) is in photovoltaic devices. Low‐cost films produced by one‐step electrodeposition could replace the co‐evaporated films used currently if their quality could be improved. It is shown that annealing such CIS films in a selenium atmosphere dramatically improves both their structural properties, as illustrated by the scanning electron micrograph. and electronic properties. magnified image
The use of CVD diamond thin films in electrochemical systems
Authors: Swain Greg M. 
Published: December 2004

The electrochemical characterization of diamond is just beginning. The study reported here deals with the growth by energy‐assisted CVD of impurity‐doped diamond electrodes (see Figure) sufficiently conductive for electrochemical measurements. The electrochemical activity of the electrodes towards various analytes, their capacitance and flat‐band potentials in several electrolytes, and their photocurrent response are discussed. magnified image