bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Prenatal Characteristics and Early Growth on Pubertal Attainment of British Girls
Authors: Maisonet Mildred , Christensen Krista Yorita , Rubin Carol , Holmes Adrianne , Flanders W. Dana , Heron Jon , Ong Ken K. , Golding Jean , McGeehin Michael A. , Marcus Michele
Published: August 2010

OBJECTIVES:

The objective of this study was to explore the influence of maternal prenatal characteristics and behaviors and of weight and BMI gain during early childhood on the timing of various puberty outcomes in girls who were enrolled in the Avon Longitudinal Study of Parents and Children.

METHODS:

Repeated self-assessments of pubertal development were obtained from ∼4000 girls between the ages of 8 and 14. Data on prenatal characteristics and weight at birth and 2, 9, and 20 months of age were obtained from questionnaires, birth records, and clinic visits. Infants' weights were converted to weight-for-age and BMI SD scores (SDSs; z scores), and change values were obtained for the 0- to 20-month and other intervals within that age range. We used parametric survival models to estimate associations with age of entry into Tanner stages of breast and pubic hair and menarche.

RESULTS:

Maternal initiation of menarche at age <12, smoking during pregnancy, and primiparity were associated with earlier puberty. A 1-unit increase in the weight SDS change values for the 0- to 20-month age interval was associated with earlier ages of entry into pubertal outcomes (0.19–0.31 years). Increases in the BMI SDS change values were also associated with earlier entry into pubertal outcomes (0.07–0.11 years).

CONCLUSIONS:

Many of the maternal prenatal characteristics and weight and BMI gain during infancy seemed to have similar influences across different puberty outcomes. Either such early factors have comparable influences on each of the hormonal processes involved in puberty, or processes are linked and awakening of 1 aspect triggers the others.
Developments in Crystalline Silicon-based Photovoltaic Product Architecture and Manufacturing
Authors: Kalejs Juris
Published: August 2010

Solar electric (Photovoltaic) crystalline silicon (c-Si) product design and diversity has changed very little over three decades of development since the inception of the photovoltaic industry. The dominant module product comprising over 90% of cumulative installations, which exceed 15 GW worldwide, employs a ubiquitous planar laminate configuration. This paper reviews the history of development of this commodity product, and examines the scientific underpinnings of the materials base of the c-Si module platform, which has provided confidence for manufacturers to lengthen product performance warranties to the current 25 year standard. Recent trends in c-Si module design, materials and manufacturing methods will also be discussed.
Mechano-chemical Synthesis, Deposition and Structural Characterization of CIGS
Authors: Bhojan Vidhya , Subramaniam Velumani , Alatorre Jesus Arenas , Asomaza Rene
Published: August 2010

CuInGaSe2 (CIGS) is a prominent thin-film photovoltaic material. However, commonly used physical vapour deposition and sputtering techniques used to fabricate CIGS thin-film photovoltaic (PV) devices are complex and expensive. Therefore non-vacuum deposition techniques such as paste coating, spray pyrolysis and electro deposition are gaining more attention in recent years. Our intention is to choose a low cost non-vacuum technique like mechano-chemical synthesis of CIGS powder, followed by screen printing. Mechano chemical synthesis is a process that induces physical and/or chemical change in the compounds by mechanical energy, such as pulverization, friction or compression. This method has some advantages for the mass production of CIGS solar cells, high productivity and short processing cycle time. In the present work CIGS powders suitable for screen-printing ink has been prepared by ball milling. High purity elemental copper granules (>99.9% pure), selenium and indium powders (>99.9% pure) and fine chips of gallium (>99.9% pure) were used as the starting materials. Ball milling was carried out for an optimized composition of CuIn0.75Ga0.25Se2 using a SPEX-8000 mixer/mill at 1200 rpm for 1.5 hours.
X-ray diffraction analysis of the milled powder shows the presence of (112), (220)/ (204), (312)/ (116), (400) and (332) peaks corresponding to CIGS chalcopyrite structure with a preferential orientation along (112) peak. The average grain size calculated by Scherrer’s formula is about 12.24 nm. Crystallographic structure of the prepared CIGS powder was analyzed by Rietveld analysis using X-ray powder diffraction data. Geometry optimization of the structure was performed and the basic structural properties have been evaluated by density functional approximation and compared with experimental results. Density of states has been simulated for the same structure inorder to have a better understanding of the distribution of atomic orbitals. FESEM analysis shows the agglomeration of nano particles. Particle size varied from 11 to 30nm. Final composition of the milled powder studied by Energy dispersive X-ray analysis gives 24.39 at% Cu, 21.42 at% In, 7.22 at% Ga and 46.97 at% Se. HRTEM analysis reveals the presence of nano crystalline particles. The interplanar distance (d-spacing) corresponding to (112), (220)/ (204), (512)/ (417) and (620)/ (604) diffraction peaks has been estimated and compared with standard values and the corresponding diffraction pattern has been simulated with simulaTEM software. CIGS ink is prepared by proper mixing of the powder with a suitable organic binder (ethyl cellulose). Screen printing is carried out on glass substrates, followed by annealing at 5 different temperatures of 300,350,400,450 and 500 degrees, in order to form a porous CIGS film. XRD analysis was carried out to study the structure of screen printed CIGS.
Reactive Sputtering of Magnesium Hydride Thin Films for Photovoltaic Applications
Authors: Platzer-Björkman Charlotte , Mongstad Trygve , Karazhanov Smagul Zh. , Maehlen Jan-Petter , Marstein Erik Stensrud , Holt Arve
Published: August 2010

Deposition of MgHx (MgH2 + Mg) thin films is performed using RF reactive sputtering in argon-hydrogen plasma. Films are characterized using x-ray diffraction (XRD), scanning electron microscopy, optical and resistivity measurements. Formation of crystalline MgH2 is confirmed by XRD, but the formation of some metallic Mg in the films could not be avoided. Increased H/Mg ratio by deposition at high hydrogen flow or high total pressure gives films that oxidize within days or weeks. Deposition at elevated substrate temperature results in improved crystallinity and stability. Initial studies of MgHx for silicon surface passivation are presented.
Elimination of Quantum Dots Cell Uptake
Authors: Xu Hengyi , Aguilar Zoraida Pascual , Jones Ben , Wei Hua , Wang Andrew
Published: August 2010

The nanotechnology is undergoing enormous attention in the areas of biological research for clinical, environmental, and life sciences applications. One of the products from this new technology that attracts researcher’s attentions is the semiconductor quantum dot (QDs) nanoparticles, QDs possess incomparable advantages such as unique size-dependent physical properties, broad absorption spectrum, precise small bandwidth emission wavelength, as well as enhanced chemical and photochemical stability. The QDs can be modified for a controlled and enhanced endocytosis, enhanced cooperative binding activity, and easy introduction of multi-functionalities for medical applications such as targeted delivery and imaging. It can be used for complex studies that play very important roles in the modern biomedical researches. However, when performing the cell related assays, the non-specific cellular uptake of QDs is a major concern because they can lead to false positives or false results. In our study, we used different surface modified QDs treated with different blocking buffers to eliminate cellular uptake. The preliminary results showed that the cellular uptake of QDs can be eliminated by surface modification of the QD materials and by performing the assays in the presence of blocking buffers. As a result of the elimination of non-specific uptake of QDs the sensitivity and specificity of detection increased significantly.
Grafting of Polyaniline onto the Surface of Amino-Functionalized Multi-Walled Carbon Nanotube via Interfacial Polymerization
Authors: Jeon In-yup , Baek Jong-beom
Published: August 2010

The mixture of polyaniline (PANi) and PANi grafted multi-walled carbon nanotube (PANi-g-MWNT) was prepared by two step reaction sequences. MWNT was first functionalized with 4-aminobenzoic acid via “direct” Firedel-Crafts acylation in polyphosphoric acid (PPA)/phosphorous pentoxide (P2O5) medium to afford aminobenzoyl-functionalized MWNT (AF-MWNT). Then, aniline was polymerized via in-situ static interfacial polymerization in H2O/CH2Cl2 in the presence of AF-MWNT in organic phase to yield the mixture of PANi and PANi-g-MWNT. The mixture was characterized with a various analytical techniques such as Fourier transform infrared spectroscopy (FT-IR), wide angle x-ray diffraction (WAXD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammogram (CV). Even after dedoping, the mixture displayed semimetallic conductivity (4.9 S/cm). The capacitance of the mixture was also greatly enhanced and its capacitance decay with respect to cycle times was significantly reduced.
Effect of Vacancies on the Thermoelectric Properties of Mg2Si Containing Sb and Bi Substitution
Authors: Dasgupta Titas , Stiewe Christian , Hassdorf Ralf , Boettcher Lothar , Mueller Eckhard
Published: August 2010

Mg2Si1-xRx (R-Sb,Bi) compositions with x=0.025, 0.05 for Sb and x=0.01,0.025, 0.05 for Bi were synthesized by induction melting of the constituent elements followed by compaction by hot pressing. Phase identification by x-ray diffraction (XRD) indicate a biphasic nature for Bi substituted compositions for x≥.025 while solid solubility for the different Sb substitutions. Abundance distribution plots of the Seebeck (S) coefficient show asymmetry in the Sb compositions and is not observed in the Bi substituted samples. This indicates presence of vacancies only in the Sb substituted compositions. Electrical conductivity (σ), Seebeck coefficient (S) and thermal conductivity (κ) values were measured from 300K to 773 K. The observed trends in the absolute values of α and S can be explained based on doping/second phase influence in Bi substitutions and due to effect of vacancies for Sb substitutions. The (κL) (phonon component) values show a significant decrease for the Sb substitutions due to the presence of vacancies. Calculation of the thermoelectric figure of merit (ZT) show a ZTmax of 0.56 for x=0.025 Bi composition compared to a ZTmax of ∼ 0.05 for Mg2Si.
Evidence-Based Practice (EBP) in Universal Design
Authors: O. Smith Roger
Published: August 2010

Policy-makers, practitioners, researchers, designers, and people with disabilities all need to
know when universal design works and when it does not. We need outcomes and evidence of design
success for best practice. Unfortunately, we are not well prepared to create and report evidence, so we
must master methods and strategies to collect, document, aggregate and report good and bad design
features to create an evidentiary database. This chapter surveys the growing field of evidence-based
practice and highlights its implications to universal design with a discussion around specific issues
around acquiring evidence particular to universal design interventions. For example, by definition,
universal design aims to create environments and products that work for everybody regardless of ability
or disability. This challenges the collection of evidence since the most reliable traditional methods to
elicit evidence are population specific. Chapter content highlights a history of evidence-based practice
and related disciplines, presents types of evidence lists resources for more in-depth discovery around
evidence-based practice, and explains specific evidence acquisition and reporting methodologies. In
addition, the chapter presents a discussion emerging out of evidence-based practice around the potential
contributions of single-subject design methodology, aggregate evidence databases and their potential as
mechanisms to acquire and use evidence to advance universal design and its implementation.
Solar Cabinet Drying of Bitter Gourd: Optimization of Pretreatments and Quality Evaluation
Authors: Jadhav Deepak Baburao , Visavale Ganesh Lotanrao , Sutar Parag P , Annapure Uday S , Thorat Bhaskar Narayan
Published: August 2010

Response surface methodology was used to optimize the pretreatments before solar cabinet drying of bitter gourd slices (6-7 mm thick). Central composite design (CCD) was used to conduct the experiments which consisted thirteen experiments with two variables, viz., blanching time (1-5 min) and potassium metabisulfite (KMS) (0.2-0.5 %). After the pretreatments, the bitter gourd slices were dried up to 6 % (Approx.) moisture content (d.b) in solar cabinet dryer at air temperature, relative humidity and air velocity in the range 38 to 62°C, 45 to 55 % and 0.9 to 1 m/s, respectively. The responses taken were chlorophyll retention (mg/100g of dried sample) and texture (hardness) of dehydrated bitter gourd slices. The optimum process condition was found at 4.24 min blanching time and 0.49 % KMS which resulted in 20.15 mg/100g chlorophyll retention and 340.55 g hardness. Some selected quality attributes of solar cabinet dried bitter gourd slices pretreated with the optimized combination of blanching time and KMS were compared with the quality of freeze and open sun dried samples and it was found that quality of solar cabinet dried product was falling in between open sun and freeze dried products. Also, the drying data of bitter gourd slices obtained during solar cabinet, freeze and open sun drying were analyzed and drying constants as well as moisture diffusivity were calculated.
Nanoindentation studies on crosslinking and curing effects of PDMS
Authors: Deuschle Julia K. , de Souza Emerson J. , Arzt Eduard , Enders Susan
Published: August 2010

Nanoindentation testing was used to investigate the mechanical properties of PDMS focusing on two aspects: Firstly, the results give a comprehensive overview of the mechanical behavior of PDMS Sylgard 184 which guides the property tailoring for many different application fields, where the mechanical behavior needs to be considered, but is not readily accessible. Secondly, the ability to measure the slight differences in the mechanical properties of these PDMS samples emphasized the high sensitivity of this technique and underlined its reliability for application on very compliant materials. The indentation results obtained in this study did not deviate from complementary tensile test data more than 5%. It was found that the elastic moduli of differently crosslinked samples cover a range of 2 orders of magnitude; for one and the same PDMS the modulus may increase 10-fold as a function of curing time.
Simulation of the co-sintering of composite structures
Authors: Schmidt Ingo , Kraft Torsten
Published: August 2010

This article presents some modifications of the solid state sintering model summarised in Riedel and Blug (2001) and shows its application for the simulation of distortions due to co-sintering of composite structures. The densification due to rearrangement in the early stage of sintering is taken into account by introducing an extra term in the viscosity. Detailed analyses of a layered thin structure are conducted with the finite element method and the results are compared to various analytical approximations for the case of a thin layer on a thick substrate. Two more examples show the applicability of the model to cases of practical interest.
Absorption and spectroscopic ellipsometry study of electron irradiated magnesium aluminate spinel
Authors: Yang Shenghong , Zhang Yueli , Mo Dang
Published: August 2010

Magnesium aluminate spinels were irradiated by electron beams with energy of 1.7 MeV and fluence from 1013 to 1017 electrons cm−2. After irradiation, the samples were annealed at different temperatures from 100 to 500 °C. Spectroscopic ellipsometry and absorption were used to study the effects of optical properties in the spinel produced by irradiation and subsequent annealing. The results obtained by absorption spectra showed that many F-type absorption centers were produced in the spinels. With increasing electron fluence, we observed an increase in optical absorption, especially in the vicinity of the absorption band at 5.3 eV. The concentration of F-type absorption centers increased as the electron fluence increased. The F-type absorption centers can be destroyed by isochronal annealing. The refractive index obtained by analyzing the ellipsometric spectra changed as the irradiation fluence and subsequent annealing temperature changed. Based on our findings, an attempt has been made to explain the above mentioned phenomena.
Finite element modelling of coverage effects during shot peening of IN718
Authors: Zimmermann Marc , Schulze Volker , Hoffmeister Jürgen
Published: August 2010

Current 3D shot peening simulation models proposed in literature do not take into account coverage as a process parameter influencing the residual state after shot peening. In this study a classic approach, using an ordered dimple pattern, and a new approach, using a stochastic dimple pattern were tested to describe the correlation between coverage, the surface topography and the residual stress state. Model verification was conducted based on X-ray and confocal white light microscopy measurements on shot peened test specimens. The test material was age hardened IN718. Simulations showed that the dimple pattern and the impact order of the shots can have a strong influence on the calculated macroscopic residual stress state. The stochastic approach enabled a realistic prediction of the surface topography and the residual stress state for arbitrary values of coverage while the classic approach strongly underestimated the number of shot impacts needed to achieve a certain value of coverage.
Effect of sowing date on the incidence of loose smut, flag smut and seed gall of wheat
Authors: Singh Rajender , Beniwal MS , Karwasra SS , Saharan Hawa Singh
Published: August 2010

An experiment was conducted to find out the effect of delay sowing on incidence of loose smut (Ustilago tritici), flag smut (Urocystis agropyri) and seed gall (Anguina tritici) of wheat. Varieties WH 896 and Raj 1555 were free from loose smut at all dates of sowing. At normal date of snwing (25 November) disease incidence varied from 28.18% (HD 2285) to 43.18 % (Sonalika). Due to delay in sowing by 20 days (15 December), the disease incidence was reduced to 21.33-38.18% and delay by 35 days (30 December) it was reduced to 18.62% -32.5 % on all susceptible varieties. At all dates of sowing, varieties WH 283, WI-I 291, WH 896 and Raj 1555 were not infected with flag smut. Other varieties were infected with the disease showing 1.3-14.57, 1.11-11.83 and 0.83-9.14% incidence at the sowing dates of 25 November (normal), 15 December (delay) and 30 December (delay), respectively. All of the varieties tested in this study were infected with seed gall nematode and disease incidence increased with delay in date of sowing. The ranges of the disease incidence were 8.16-20.14, 12.33-28.91 and 14.16-36.66% at first, second tnd third date of sowing, respectively.Key Words: Loose smut; flag smut; seed gall nematode; wheat; sowing date.DOI: 10.3329/bjar.v34i1.5746Bangladesh J. Agril. Res. 34(1) : 1-4, March 2009
Development of fertilizer recommendation for the cropping pattern potato-boro-T. aman in irrigated medium highland condition under AEZ -9
Authors: Ali MR , Costa DJ , Sayed MA , Khan MAH , Abedin JA
Published: August 2010

The experiment was carried out in the Old Brahmaputra Floodplain soil at the farmer's field of Farming System Research and Development (FSRD) site, Kushumhati, Sherpur under Sherpur district in the medium high land under AEZ-9 for the three consecutive years 2003-06 to determine economic combined dose of organic and inorganic fertilizers for Potato-Boro-T.aman cropping pattern. Six treatment management packages including one farmer's practices, and one fertilizer control were tested. The other four treatments were soil test based (STB) fertilizer dose for moderate and high yield goals (MYG and HYG), STB based fertilizer dose for HYG plus 5 t/ha cowdung (IPNS) and fertilizer dose for Fertilizer Recommendation Guide'97 (FRG '97). Average of three years' results showed that recommended fertilizer dose based on the FRG '97 was more economic than all other fertilizer doses for the whole pattern. But the treatment Integrated Plant Nutrition Systems based on fertilizer management with cowdung for high yield goal produced the maximum grain and straw yields in the first crop. Application of cowdung had no significant effect on the yield of succeeding crops. The variable cost was higher for the treatment consisting of cowdung due to additional cost of cowdung. The highest marginal rate of return 1626% was obtained from recommended fertilizer based on the FRG '97.Key Words: Balanced fertilization; cropping pattern; yield; economicsDOI: 10.3329/bjar.v34i1.5751Bangladesh J. Agril. Res. 34(1) : 41-49, March 2009
Effect of integrated use of organic manures with chemical fertilizers in the rice-rice cropping system and its impact on soil health
Authors: Ali ME , Islam MR , Jahiruddin M
Published: August 2010

A field experiment was conducted during 2003-2004 at Bangladesh Agricultural University farm, Mymensingh to evaluate the suitability of different sources of organic materials for integrated use with chemical fertilizers for the Boro-Fallow-T. Aman rice cropping pattern. The experiment was set up in a randomized complete block design (RCBD) with three replications. Eight-treatments, formulated from organic manure and chemical fertilizers have been imposed. The treatment combinations are T1: control, T2: 70% NPKS, T3: 100% NPKS, T4: 70% NPKS + rice straw (RS) @ 5 t/ha, T5: 70% NPKS + dhaincha (DH) @ 15 t/ha, Tb: 70% NPKS + mungbean residue (MBR) @ 10 t/ha, T7: 70% NPKS + cowdung (CD) @ 5 t/ha and T8: 70% NPKS + poultry manure (PM) @ 3 t/ha. Organic manure or crop residue was applied to T. Aman rice and their residual effects were observed in the following Boro rice. Application of 70% NPKS + PM produced the highest grain yield of T. Aman rice, which was identical to that obtained with 100% NPKS with no manure. In Boro season. application of 100% NPKS produced the highest grain yield of 6.87 t/ha, which was identical with the application of 70% NPKS + PM (6.57 t/ha). The total grain yield in the cropping pattern ranged from 5.14 t/ha in T1 (control) treatment to 12.29 t/ha in the 100% NPKS. The application of 3 t/ha PM with 70% NPKS (T8) produced the total yield of 12.09 t/ha followed by 11.59 t/ha in the treatment containing 10 t/ha MBR plus 70% NPKS (T6). It appears that the application of 3 t/ha PM once in a year with 70% NPKS can reduce the use of 30% NPKS as fertilizers. There were negative balances for N and K with the highest mining of K, while the balances for P and S were positive. The economic analysis reveals that most of the treatments produced BCR (benefit-cost ratio) of more than 3.0 showing that they all are economically viable. The integrated use of fertilizers and manure resulted in considerable improvement in soil health by increasing organic matter, available P, and S contents of soils. The overall findings of the study indicate that the integrated use of chemical fertilizer and manure is important for sustainable crop yield in a rice-rice cropping pattern. Key Words: Organic manures; chemical fertilizer; soil health. DOI: 10.3329/bjar.v34i1.5757Bangladesh J. Agril. Res. 34(1) : 81-90, March 2009
Genetic variation and trait relationship in the exotic and local eggplant germplasm
Authors: Islam MS , Uddin MS
Published: August 2010

Sixteen genotypes of local and exotic germplasms were studied to estimate variability, hcritability, genetic advance, and correlation coefficients. High genotypic and phenotypic coefficients of variation were obtained for number of fruits/plant, individual fruit weight, and yield per plant. Heritability and genetic advance were also high for these traits indicating the possibility of selection to improve these characters. Yield of fruits showed highly significant and positive association with number of fruits per plant and individual fruit weight, which indicate the importance of these characters during selection for high yielding genotypes in eggplant. Among the genotypes, Islampuri produced the highest fruit yield (58.8 t/ha) followed by Tall begun (52.8 t/ha) and EG 120 (49.6 t/ha). Incidence of borer infestation ranged from 3.0 to 20.6 %. The lowest borer infestation was found in EG 120 (3.0%), while it was the highest in EG 192 (20.6%) Key Words: Genetic variation; trait relationship; exotic and local germplasm; eggplant. DOI: 10.3329/bjar.v34i1.5758Bangladesh J. Agril. Res. 34(1) : 91-96, March 2009
Seasonal Variation, Chemical Composition, and Analgesic and Antimicrobial Activities of the Essential Oil from Leaves of Tetradenia riparia (Hochst.) Codd in Southern Brazil
Authors: Gazim Zilda Cristiani , Amorim Ana Carolina L. , Hovell Ana Maria C. , Rezende Claudia Moraes , Nascimento Izalina Ansilieiro , Ferreira Gilberto Alves , Cortez Diógenes Aparício Garcia
Published: August 2010

The seasonal variation of the chemical composition of the essential oil from fresh leaves of Tetradenia riparia (Hochst.) Codd grown in southern Brazil was analyzed by GC-MS, and the analgesic and antimicrobial activities of this oil were assayed. The yield of essential oil ranged from 0.17% to 0.26%, with the maximum amount in winter and the minimum in spring. The results obtained from principal components analysis (PCA) revealed the existence of high chemical variability in the different seasons. The samples were clearly discriminated into three groups: winter, autumn, and spring-summer. Samples collected during winter contained the highest percentages of calyculone (24.70%), abietadiene (13.54%), and viridiflorol (4.20%). In autumn, the major constituents were ledol (8.74%) and cis-muurolol-5-en-4-α-ol (13.78%). Samples collected in spring-summer contained the highest percentages of fenchone (12.67%), 14-hydroxy-9-epi-caryophyllene (24.36%), and α-cadinol (8.33%). Oxygenated sesquiterpenes were predominant in all the samples analyzed. The observed chemovariation might be environmentally determined by a seasonal influence. The essential oil, when given orally at a dose of 200 mg/kg, exhibited good analgesic activity on acetic acid-induced writhing in mice, inhibiting the constrictions by 38.94% to 46.13%, and this effect was not affected by seasonal variation. The antimicrobial activity of the essential oil against the bacterial strains: Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Morganella morganii, and Enterobacter cloacae, and the pathogenic fungus Candida albicans was assessed by the disc diffusion method and determination of the minimum inhibitory concentration. The results obtained, followed by measurement of the minimum inhibitory concentration (MIC), indicated that S. aureus, B. subtilis, and Candida albicans were the most sensitive microorganisms, showing largest inhibition, and the lowest MIC values varied from 15.6 to 31.2 µg/mL, 7.8 to 15.6 µg/mL, and 31.2 to 62.5 µg/mL, respectively.
Temperature Induced Solubility Transitions of Various Poly(2-oxazoline)s in Ethanol-Water Solvent Mixtures
Authors: Lambermont-Thijs Hanneke M. L. , Kuringen Huub P. C. van , Put Jeroen P. W. van der , Schubert Ulrich S. , Hoogenboom Richard
Published: August 2010

The solution behavior of a series of poly(2-oxazoline)s with different side chains, namely methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, phenyl and benzyl, are reported in ethanol-water solvent mixtures based on turbidimetry investigations. The LCST transitions of poly(2-oxazoline)s with propyl side chains and the UCST transitions of the poly(2-oxazoline)s with more hydrophobic side chains are discussed in relation to the ethanol-water solvent composition and structure. The poly(2-alkyl-2-oxazoline)s with side chains longer than propyl only dissolved during the first heating run, which is discussed and correlated to the melting transition of the polymers.
Fabrication of Extrinsically Conductive Silicone Rubbers with High Elasticity and Analysis of Their Mechanical and Electrical Characteristics
Authors: Saleem Anjum , Frormann Lars , Soever Alexandru
Published: August 2010

Conductive plastics are attracting more and more interest in electronics due to their light weight and inability to rust, which are common problems associated with metals. The field of conducting plastics is not new. Much work has been done to impart electrical conductivity to mechanically strong polymers such as polypropylene, polycarbonate and epoxies, etc. However there is a need to fabricate more flexible and elastic conductive polymers such as conducting silicone rubbers for use in various applications. In this work silicone rubbers reinforced with conductive fillers have been fabricated for use as sensors in textiles to detect the resistance change produced by stretching or relaxing. The variations of electrical resistance have been investigated by stretching and releasing the strands of conductive rubbers as a function of time. Two types of silicone rubbers—addition cured and condensation cured—were compounded with different electrically conductive fillers, among which carbon fibers have shown the best results. The carbon fibers improved the electrical conductance of the rubbers, even in very low weight percentages. The increasing concentration of fillers decreases the elasticity of the rubber. In order to keep the original properties of silicones, the filler concentration was kept as low as possible to produce a significantly detectable signal. The fabricated compounds were analyzed for their mechanical properties by stress strain curves. Such materials find their applications in electronics, antistatic applications, sports and the automotive industry where they can be used as deformation sensors.
How Should Staphylococcal Food Poisoning Outbreaks Be Characterized?
Authors: Hennekinne Jacques-Antoine , Ostyn Annick , Guillier Florence , Herbin Sabine , Prufer Anne-Laure , Dragacci Sylviane
Published: August 2010

Staphylococcal food poisoning is one of the most common food-borne diseases and results from the ingestion of staphylococcal enterotoxins (SEs) preformed in food by enterotoxigenic strains of Staphylococcus aureus. To date, more than 20 SEs have been described: SEA to SElV. All SEs have superantigenic activity whereas only a few have been proved to be emetic, representing a potential hazard for consumers. Characterization of staphylococcal food poisoning outbreaks (SFPOs) has considerably progressed compared to 80 years ago, when staphylococci were simply enumerated and only five enterotoxins were known for qualitative detection. Today, SFPOs can be characterized by a number of approaches, such as the identification of S. aureus biovars, PCR and RT-PCR methods to identify the se genes involved, immunodetection of specific SEs, and absolute quantification by mass spectrometry. An integrated gene-to-protein approach for characterizing staphylococcal food poisoning is advocated.
Quantification of DMS aerosol-cloud-climate interactions using the ECHAM5-HAMMOZ model in a current climate scenario
Authors: Thomas M. A. , Suntharalingam P. , Pozzoli L. , Rast S. , Devasthale A. , Kloster S. , Feichter J. , Lenton T. M.
Published: August 2010

Abstract. The contribution of ocean dimethyl sulfide (DMS) emissions to changes in cloud microphysical properties is quantified seasonally and globally for present day climate conditions using an aerosol-chemistry-climate general circulation model, ECHAM5-HAMMOZ, coupled to a cloud microphysics scheme. We evaluate DMS aerosol-cloud-climate linkages over the southern oceans where anthropogenic influence is minimal. The changes in the number of activated particles, cloud droplet number concentration (CDNC), cloud droplet effective radius, cloud cover and the radiative forcing are examined by analyzing two simulations: a baseline simulation with ocean DMS emissions derived from a prescribed climatology and one in which the ocean DMS emissions are switched off. Our simulations show that the model realistically simulates the seasonality in the number of activated particles and CDNC, peaking during Southern Hemisphere (SH) summer coincident with increased phytoplankton blooms and gradually declining with a minimum in SH winter. In comparison to a simulation with no DMS, the CDNC level over the southern oceans is 128% larger in the baseline simulation averaged over the austral summer months. Our results also show an increased number of smaller sized cloud droplets during this period. We estimate a maximum decrease of up to 15–18% in the droplet radius and a mean increase in cloud cover by around 2.5% over the southern oceans during SH summer in the simulation with ocean DMS compared to when the DMS emissions are switched off. The global annual mean top of the atmosphere DMS aerosol all sky radiative forcing is −2.03 W/m2, whereas, over the southern oceans during SH summer, the mean DMS aerosol radiative forcing reaches −9.32 W/m2.
Long term measurements of sulfur dioxide, nitrogen dioxide, ammonia, nitric acid and ozone in Africa using passive samplers
Authors: Adon M. , Galy-Lacaux C. , Yoboué V. , Delon C. , Lacaux J. P. , Castera P. , Gardrat E. , Pienaar J. , Al Ourabi H. , Laouali D. , Diop B. , Sigha-Nkamdjou L. , Akpo A. , Tathy J. P. , Lavenu F. , Mougin E.
Published: August 2010

Abstract. In this paper we present the long term monitoring of ambient gaseous concentrations within the framework of the IDAF (IGAC-DEBITS-AFRICA) program. This study proposes for the first time an analysis of long-term inorganic gas concentrations (1998 to 2007) of SO2, NO2, HNO3, NH3 and O3, determined using passive samplers at seven remote sites in West and Central Africa. Sites are representative of several African ecosystems and are located along a transect from dry savannas-wet savannas-forests with sites at Banizoumbou (Niger), Katibougou and Agoufou (Mali), Djougou (Benin), Lamto (Cote d'Ivoire), Zoetele (Cameroon) and Bomassa (Congo). The strict control of measurement techniques as well as the validation and inter-comparison studies conducted with the IDAF passive samplers assure the quality and accuracy of the measurements. For each type of African ecosystem, the long term data series have been studied to document the levels of surface gaseous concentrations. The seasonal and interannual variability have also been analyzed as a function of emission source variations. We compared the measured West and Central African gas concentrations to results obtained in other parts of the world. Results show that the annual mean concentrations of NO2, NH3, HNO3 measured in dry savannas are higher than those measured in wet savannas and forests that have quite similar concentrations. Annual mean NO2 concentrations vary from 0.9±0.2 in forests to 2.4±0.4 ppb in the dry savannas, NH3 from 3.9±1.4 to 7.4±0.8 ppb and HNO3 from 0.2±0.1 to 0.5±0.2 ppb. Annual mean O3 and SO2 concentrations are lower for all ecosystems and range from 4.0±0.4 to 14.0±2.8 and from 0.3±0.1 to 1.0±0.2 ppb, respectively. A focus on the processes involved in gas emissions from dry savannas is presented in this work, providing explanations for the high concentrations of all gases measured at the three dry savannas sites. At these sites, seasonal concentrations of all gases are higher in the wet season. Conversely, concentrations are higher in the dry season in the wet savannas. In forested regions, we measure no significant difference between wet and dry seasons. This unique database of long term gases concentrations monitoring is available at: http://medias.obs-mip.fr/idaf/.
A numerical comparison of different methods for determining the particle formation rate
Authors: Vuollekoski H. , Sihto S.-L. , Kerminen V.-M. , Kulmala M. , Lehtinen K. E. J.
Published: August 2010

Abstract. Different methods of determining formation rates of 3 nm particles are compared, basing on analysis of simulated data, but the results are valid for analyses of experimental particle size distribution data as well. The study shows that the method of determining formation rates indirectly from measured number concentration data of 3–6 nm particles is generally in good agreement with the theoretical calculation with a systematic error of 0–20%. While this is often accurate enough, a simple modification to the approximative equation for the formation rate is recommended. Additionally, the temporal connection between the concentration of the nucleating vapour and the formation rate is studied. It is concluded that the often used power-law connecting these two is inaccurate.
Soil moisture modelling of a SMOS pixel: interest of using the PERSIANN database over the Valencia Anchor Station
Authors: Juglea S. , Kerr Y. , Mialon A. , Lopez-Baeza E. , Braithwaite D. , Hsu K.
Published: August 2010

Abstract. In the framework of Soil Moisture and Ocean Salinity (SMOS) Calibration/Validation (Cal/Val) activities, this study addresses the use of the PERSIANN-CCS1database in hydrological applications to accurately simulate a whole SMOS pixel by representing the spatial and temporal heterogeneity of the soil moisture fields over a wide area (50×50 km2). The study focuses on the Valencia Anchor Station (VAS) experimental site, in Spain, which is one of the main SMOS Cal/Val sites in Europe. A faithful representation of the soil moisture distribution at SMOS pixel scale (50×50 km2) requires an accurate estimation of the amount and temporal/spatial distribution of precipitation. To quantify the gain of using the comprehensive PERSIANN database instead of sparsely distributed rain gauge measurements, comparisons between in situ observations and satellite rainfall data are done both at point and areal scale. An overestimation of the satellite rainfall amounts is observed in most of the cases (about 66%) but the precipitation occurrences are in general retrieved (about 67%). To simulate the high variability in space and time of surface soil moisture, a Soil Vegetation Atmosphere Transfer (SVAT) model – ISBA (Interactions between Soil Biosphere Atmosphere) is used. The interest of using satellite rainfall estimates as well as the influence that the precipitation events can induce on the modelling of the water content in the soil is depicted by a comparison between different soil moisture data. Point-like and spatialized simulated data using rain gauge observations or PERSIANN – CCS database as well as ground measurements are used. It is shown that a good adequacy is reached in most part of the year, the precipitation differences having less impact upon the simulated soil moisture. The behaviour of simulated surface soil moisture at SMOS scale is verified by the use of remote sensing data from the Advanced Microwave Scanning Radiometer on Earth observing System (AMSR-E). We show that the PERSIANN database provides useful information at temporal and spatial scales in the context of soil moisture retrieval. 1Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Cloud Classification System – http://chrs.web.uci.edu/persiann
Extraction of thalweg networks from DTMs: application to badlands
Authors: Thommeret N. , Bailly J. S. , Puech C.
Published: August 2010

Abstract. To study gully spatial patterns in the badlands using a continuous thalweg vector network, this paper presents methods to extract the badlands' thalweg network from a regular grid digital terrain model (DTM) by combining terrain morphology indices with a drainage algorithm. This method will delineate a thalweg only where the DTM denotes a significant curvature with respect to DTM accuracy and relies on three major steps. First, discontinuous concave areas were detected from the DTM using morphological criteria, either the plan curvature or the convergence index. Second, the concave areas were connected using a drainage algorithm, which provides a continuous, thick, tree-structured scheme. We assumed that these areas were physically significant and corresponded to a gully floor. Finally, the thick path was reduced to its main course and vectorised to obtain a thalweg network. The methods were applied to both virtual and actual DTM cases. The actual case was a LiDAR DTM of the Draix badlands in the French Alps. The obtained networks were quantitatively compared, both with a network obtained using the usual drainage area criteria and with a reference network mapped in the field. The CI-based network showed the great potential for thalweg network extraction.
On the sampling distribution of the coefficient of L-variation for hydrological applications
Authors: Viglione A.
Published: August 2010

Abstract. The coefficient of L-variation (L-CV) is commonly used in statistical hydrology, in particular in regional frequency analysis, as a measure of steepness of the frequency curve. The aim of this work is to infer the full frequency distribution of the sample L-CV (and, consequently, its confidence intervals) for small samples and without making assumptions on the underlying parent distribution of the hydrological variable of interest. Several two-parameters candidate distributions are compared for a wide range of cases using Monte-Carlo simulations. A distribution-free method, recently proposed to estimate the variance structure of sample L-moments, is used to provide the parameters for the candidate distributions. It is shown that the log-Student t distribution approximates best, in most of the cases, the distribution of the sample L-CV and that a simple correction of the bias for the sample L-CV and its variance improves the fit. Also, the parametric method proposed here is demonstrated to perform better than the non-parametric bootstrap. An example of how this result could be used in hydrology is presented, namely in the comparison of methods for regional flood frequency analysis.
Potential Effects of Sleep Deprivation on Sensorimotor Integration during Quiet Stance in Young Adults
Authors: Nielson Chantelle A. , Deegan Emily G. , Hung Aaron S.L. , Nunes Abraham J
Published: August 2010

The purpose of this study was to compare the effects of sleep deprivation and rest on postural control. It was hypothesized that significant increases in COP deviations will occur after sleep deprivation. Methods. Four healthy adults (age= 21.50 years; mass= 68.93 kg) participated in two protocols involving sleep and sleep-deprivation. Within each condition multiple 40s impairments of visual, somatosensory, and/or vestibular sensory feedback were performed. Balance was quantified using root-mean-square (RMS) of the centre of pressure (COP) and COP Variance. Results. Two-way ANOVA demonstrated no significant effect of sleep deprivation on balance between sensory insults. Paired t-tests were performed nonetheless and revealed significant differences within the sleep-deprived condition. COP RMS and Variance were significantly greater medio-laterally with all systems impaired (ALL) (3.43 ± 0.63 mm, p
Synthesis and Biological Activities of Azalamellarins
Authors: Boonya‐udtayan Sasiwadee , Yotapan Nattawut , Woo Christina , Bruns Carson J. , Ruchirawat Somsak , Thasana Nopporn
Published: August 2010

The synthesis of azalamellarins, a new series of lactam analogues of biologically active lamellarins, was achieved using CuI‐mediated and microwave‐assisted CNamide bond formation. Seventeen azalamellarins, including N‐allylazalamellarins and N‐propylazalamellarins χ‐D, L‐N, and J‐dehydro J, were synthesized and evaluated for their cytotoxicity against the cancer cell lines HuCCA‐1, A‐549, HepG2, and MOLT‐3. The results showed that certain azalamellarins exhibited good activities in the micromolar IC50 value range (IC50=the drug concentration that causes 50 % of cell‐growth inhibition after 72 h of continuous exposure to the test molecule), comparable to their parent lamellarin analogue.
Kinetic Evaluation of Cooperative [Co(salen)] Catalysts in the Hydrolytic Kinetic Resolution of rac‐Epichlorohydrin
Authors: Zhu Xunjin , Venkatasubbaiah Krishnan , Weck Marcus , Jones Christopher W.
Published: August 2010

A wide variety of [Co(salen)] catalysts with different structures designed to enhance salen–salen cooperative interactions have been reported as catalysts for the hydrolytic kinetic resolution (HKR) of epoxides. However, the myriad catalysts have been evaluated under inconsistent experimental conditions, at different catalyst loadings, at different temperatures, with various epoxides and in several different laboratories, making rigorous comparisons between the catalysts impossible. To this end, 12 representative catalysts from our studies, as well as catalysts originally described by others, are reported in the HKR of epichlorohydrin under rigorously identical conditions. The comparison of the reactivity and selectivity of the different catalysts indicates that the soluble, oligomeric [Co(salen)] catalysts with cyclic frameworks impart the highest activity and enantioselectivity (>99 % ee, krel>99) in this representative reaction, requiring very short reaction times (<30 min), including the most active catalyst reported to date for the target reaction. In general, it is found that soluble polymer or oligomer‐supported catalysts are more active than insoluble supported catalysts under the conditions used. Among the insoluble catalysts, a polymer resin supported [Co(salen)] catalyst with excellent enantioselectivity (>99 % ee, krel>99) and medium reaction time (222 min), is the most active and selective of the class. The lessons demonstrated herein regarding design of active and selective catalysts offer useful insights into refining design strategies for other related cooperative catalytic reactions, suggesting emphases on catalyst flexibility and solubility under reaction conditions.