bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recombination process in solar cells: Impact on the carrier transport
Authors: Gurevich Yuri G. , Velázquez‐Pérez Jesus E. 
Published: August 2012

AbstractThickness of Si solar cells is being reduced below 200 µm to reduce costs and improve their performance. In conventional solar cells recombination of photo‐generated charge carriers plays a major limiting role in the cell efficiency. High quality thin‐film solar cells may overcome this limit if the minority diffusion lengths become large as compared to the cell dimensions, but, strikingly, the conventional model fails to describe the cell electric behaviour under these conditions. Moreover, it is shown that in the conventional model the reverse‐saturation current diverges (tends to infinity) in thin solar cells. A new formulation of the basic equations describing charge carrier transport in the cell along with a set of boundary conditions is presented. An analytical closed‐form solution is obtained under a linear approximation. In the new framework given, the calculation of the open‐circuit voltage of the solar cell diode does not lead to unphysical results. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of ultrasound on the Si‐SiO2 system
Authors: Kropman Daniel , Dolgov S. 
Published: August 2012

AbstractThe effect of ultrasonic treatment (UST) on the defect structure of the Si–SiO2 system by means of electron spin resonance (ESR), metallography, MOS capacitance technique, and secondary ions mass‐spectroscopy (SIMS) is presented. The non‐monotonous dependence of the defect densities on the US wave intensity has been observed. The influence of the UST frequency on the ESR signal intensity of the defect centers depended on the defect type and structure, and may be caused by dissipation of vibrational energy which is a function of the defect center type. The influence of the UST on the properties of the Si–SiO2 interface depends on the oxide thickness and crystallographic orientation. The density of point defects and absorbed impurities at the Si–SiO2 interface can be reduced and its electrical parameters improved by an appropriate choice of the UST and oxidation conditions. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A novel and efficient method combining acid leaching and thermal annealing for impurities removal from silicon intended for photovoltaic application
Authors: Khalifa M. , Hajji M. , Ezzaouia H. 
Published: August 2012

AbstractThe aim of this work is the purification of MG‐silicon powder using a method combining acid leaching and thermal annealing. It describes experiment carried out by using a tungsten lamps furnace (rapid thermal processing, RTP) to purify silicon powder under controlled atmosphere. This process enables to segregate the impurities to the surface of silicon powder where they can be extracted by partial dissolution in acids. Obtained silicon was investigated by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP‐AES) method. Major impurities present in silicon powder were Al, K, Fe, Na, Ca, Mg and B. After purification the concentration of major impurities significantly decreased. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and photoluminescence properties of Tb‐doped nitrogen‐rich silicon nitride films
Authors: An Y.‐T. , Labbé C. , Morales M. , Marie P. , Gourbilleau F. 
Published: August 2012

AbstractTerbium (Tb) doped nitrogen‐rich silicon nitride thin films were prepared on [100] Si substrate by reactive magnetron co‐sputtering in pure nitrogen atmosphere. The microstructure and optical properties of the films were investigated by means of ellipsometric spectroscopy (ES), atomic force microscopy (AFM), X‐ray diffraction (XRD), Raman scattering and Fourier transform infrared (FTIR) spectroscopies as well as by photoluminescence (PL) experiments. A notable emission from Tb3+ ions was obtained for the as‐deposited layer, while the maximum intensity was found from 600 °C‐annealed sample. Deducing from PL excitation (PLE) analysis, a mechanism of excitation of Tb3+ ions was proposed: the band tail states of matrix play a minor role in the energy transfer process, while the host carriers across the optical gap acted as effective sensitizers for Tb3+ ions (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Unified analytical treatment for calculation of the two‐dimensional Franck–Condon factors using the duschinsky transformation
Authors: Mamedov B. A. 
Published: August 2012

AbstractIncluding binomial expansion theorems, we present an analytical formula for calculating Franck–Condon (FC) factors of two‐dimensional (2D) harmonic oscillators including the Duschinsky effect. The FC principle has various practical applications in quantum modeling of electronic spectra of polyatomic molecules. The 2D FC factors are expressed through the binomial coefficients. Use of the memory of the computer for the calculation of binomial coefficients may extend the limits to large arguments for users and result in speeder calculation, should such limits be required in practice. Accurate numerical results are provided to validate the proposed algorithm. © 2012 Wiley Periodicals, Inc.
Quantized output feedback stabilization of uncertain systems with input nonlinearities via sliding mode control
Authors: Zheng Bo‐Chao , Yang Guang‐Hong 
Published: August 2012

SUMMARYThis paper is concerned with the quantized output feedback stabilization problem for a class of uncertain systems with nonsmooth nonlinearities in the actuator device via sliding mode control schemes. It is assumed that system signals are quantized before being transmitted through communication channels. First, a dynamical compensator is developed to estimate unmeasurable system state. Then a sliding surface, in the augmented space using the system output and the estimated state, is proposed, and an adaptive sliding mode control scheme with a static adjustment law of the quantization parameter is established. It is shown that the proposed quantized feedback control strategy is able to tackle parameter uncertainty, external disturbances, and nonsymmetric input nonlinearity simultaneously and guarantees the reachability of the sliding modes of the uncertain system. Finally, an example is given to verify the validity of the theoretical results. Copyright © 2012 John Wiley & Sons, Ltd.
Imaging and Measuring the Molecular Force of Lymphoma Pathological Cells Using Atomic Force Microscopy
Authors: Li Mi , Xiao Xiubin , Liu Lianqing , Xi Ning , Wang Yuechao , Dong Zaili , Zhang Weijing 
Published: August 2012

SummaryAtomic force microscopy (AFM) provides a new technology to visualize the cellular topography and quantify the molecular interactions at nanometer spatial resolution. In this work, AFM was used to image the cellular topography and measure the molecular force of pathological cells from B‐cell lymphoma patients. After the fluorescence staining, cancer cells were recognized by their special morphological features and then the detailed topography was visualized by AFM imaging. The AFM images showed that cancer cells were much rougher than healthy cells. CD20 is a surface marker of B cells and rituximab is a monoclonal antibody against CD20. To measure the CD20‐rituximab interaction forces, the polyethylene glycol (PEG) linker was used to link rituximab onto the AFM tip and the verification experiments of the functionalized probe indicated that rituximab molecules were successfully linked onto the AFM tip. The CD20‐rituximab interaction forces were measured on about 20 pathological cells and the force measurement results indicated the CD20‐rituximab binding forces were mainly in the range of 110–120 pN and 130–140 pN. These results can improve our understanding of the topography and molecular force of lymphoma pathological cells. SCANNING 35:40‐46, 2013. © 2012 Wiley Periodicals, Inc.
Enzymatic Growth of Quantum Dots: Applications to Probe Glucose Oxidase and Horseradish Peroxidase and Sense Glucose
Authors: Saa Laura , Pavlov Valeri 
Published: August 2012

AbstractThree innovative assays are developed for the detection of enzymatic activities of glucose oxidase (GOx) and horseradish peroxidase (HRP) by the generation of CdS quantum dots (QDs) in situ using non‐conventional enzymatic reactions. In the first assay, GOx catalyzes the oxidation of 1‐thio‐β‐D‐glucose to give 1‐thio‐β‐D‐gluconic acid. The latter is spontaneously hydrolyzed to β‐D‐gluconic acid and H2S, which in the presence of cadmium nitrate yields fluorescent CdS nanoparticles. In the second assay HRP catalyzes the oxidation of sodium thiosulfate with hydrogen peroxide generating H2S and consequently CdS QDs. The combination of GOx with HRP, allowed quantification of glucose in plasma by following growth of fluorescent QDs.
Implementation of Self-Organizing Maps (SOM) to analyses of environmental parameters and phytoplankton biomass in a macrotidal estuary and artificial lake
Authors: Jahan Roksana , Choi Hyu Chang , Park Young Seuk , Park Young Cheol , Seo Ji Ho , Choi Joong Ki 
Published: August 2012

Self-Organizing Maps (SOM) have been used for patterning and visualizing ten environmental parameters and phytoplankton biomass in a mactrotidal (>10 m) Gyeonggi Bay and artificial Shihwa Lake during 1986–2004. SOM segregated study areas into four groups and ten subgroups. Two strikingly alternative states are frequently observed: the first is a diverse non-eutrophic state designated by three groups (SOM 1–3), and the second is a eutrophic state (SOM 4: Shihwa Lake and Upper Gyeonggi Bay; summer season) characterized by enhanced nutrients (3 mg l−1 dissolved inorganic nitrogen, 0.1 mg l−1 PO4) that act as a signal and response to that signal as algal blooms (24 µg chlorophyll-a l−1). Bloom potential in response to nitrification is affiliated with high temperature (r = 0.26), low salinity (r = −0.40) and suspended solids (r = –0.27). Moreover, strong stratification in the Shihwa Lake has accelerated harmful algal blooms and hypoxia. The non-eutrophic states (SOM 1–3) are characterized by macro-tidal estuaries exhibiting a tolerance to pollution with nitrogen-containing nutrients and retarding any tendency toward stratification. SOM 1 (winter) is more distinct from SOM 4 due to higher suspended solids (>50 mg l−1) caused by resuspension that induces light limitation and low chlorophyll-a (<5 µg l−1). In addition, eutrophication-induced shifts in phytoplankton communities are noticed during all the seasons in Gyeonggi Bay. Overall, SOM showed high performance for visualization and abstraction of ecological data and could serve as an efficient ecological map that can specify blooming regions and provide a comprehensive view on the eutrophication process in a macrotidal estuary.
On the ionospheric source region of cold ion outflow
Authors: Li K. , Haaland S. , Eriksson A. , André M. , Engwall E. , Wei Y. , Kronberg E. A. , Fränz M. , Daly P. W. , Zhao H. , Ren Q. Y. 
Published: August 2012

Recent studies have shown that low energy ions constitute a significant part of the total ion population in the Earth's magnetosphere. In this study, we have used a comprehensive data set with measurements of cold (total energy less than 70 eV) ion velocity and density to determine their source. This data set is derived from Cluster satellite measurements combined with solar wind and interplanetary magnetic field measurements and geomagnetic indices. By using the guiding center equation of motion, we were able to calculate the trajectories and thus determine the source region of the cold ions. Our results show that the polar cap region is the primary source for cold ions. We also found that the expansion and contraction of the polar cap as a consequence of changes in solar wind parameters were correlated with the source region size and intensity of the cold ion outflow. Elevated outflow fluxes near the nightside auroral zone and the dayside cusps during disturbed conditions suggest that energy and particle precipitation from the magnetosphere or directly from the solar wind can enhance the outflow of cold ions from the ionosphere.
Distribution, Size, and Origin of Juvenile Chinook Salmon in Shallow-Water Habitats of the Lower Columbia River and Estuary, 2002–2007
Authors: Roegner G. Curtis , McNatt Regan , Teel David J. , Bottom Daniel L. 
Published: August 2012

Abstract
We monitored fish assemblages monthly at estuarine and tidal freshwater sites in the lower Columbia River and estuary from January 2002 through September 2007 in order to identify specific salmon stocks and migration stages that may benefit from habitat restoration initiatives. We report landscape-scale and seasonal variation in abundance, size, hatchery production (based on adipose fin clips), and genetic stock of origin of juvenile Chinook salmon Oncorhynchus tshawytscha. From fish implanted with coded wire tags (CWTs), we also determined the sites of release and inferred migration patterns. Chinook salmon were found in diverse life history stages and forms, including fry migrants, fingerlings, and (fewer) yearlings. Abundance increased in February and decreased in August, but salmon were present in all months each year. Spatial gradients in abundance and size were strong, with fewer but larger fish in brackish than in tidal freshwater zones. Overall, 30% of the Chinook salmon measured were fry (≤60 mm) that were likely naturally produced fish. These occurred at higher mean monthly proportions in tidal freshwater than in estuarine zones. In contrast, most larger fish were probably raised in hatcheries. Genetic stock assessment revealed that the majority of the Chinook salmon analyzed were from fall-run stock groups originating in the lower Columbia River, with 15% originating from other stock groups. Of these minority contributors, about 6% were identified as upper Columbia River summer–fall-run Chinook salmon while seven other stock groups accounted for the remainder, including 3% from transplants originating in southern Oregon's Rogue River. Recaptures of tagged fish revealed maximum migration times of 143 d for subyearlings and 52 d for yearlings, and both CWT and genetic data indicated that fall Chinook salmon from coastal rivers occasionally entered the estuary. These data demonstrated a widespread temporal and spatial distribution of subyearling Chinook salmon in shallow-water habitats of the lower Columbia River and estuary.
Received June 28, 2011; accepted February 28, 2012
Prognostic significance of pituitary tumour‐transforming gene‐binding factor (PBF) expression in papillary thyroid carcinoma
Authors: Hsueh Chuen , Lin Jen‐Der , Chang Yu‐Sun , Hsueh Swei , Chao Tzu‐Chieh , Yu Jau‐Song , Jung Shih‐Ming , Tseng Ngan‐Ming , Sun Jui‐Hung , Kuo Shau‐Yun , Ueng Shir‐Hwa 
Published: August 2012

SummaryBackgroundPituitary tumour‐transforming gene (PTTG)‐binding factor (PBF), originally known as PTTG1 interacting protein (PTTG1IP), has been found to be significantly increased in well‐differentiated thyroid cancer and independently associated with early tumour recurrence.ObjectiveTo assess the prognostic significance of PBF expression in a large cohort of papillary thyroid carcinoma (PTC) patients with a long‐term follow‐up.Design and patientsRetrospective analysis of PBF expression in PTC cases at different stages and correlate it with various clinicopathological parameters and patient survival. Subjects included 153 patients who received a thyroid operation for PTC at Chang Gung Memorial Hospital between 1991 and 2000. All patients had a complete follow‐up till the end of 2010.MeasurementsImmunohistochemical study for PBF expression on tissue sections from tumour specimens. Bond automated machine (Leica Microsystems, Germany) with a polyclonal rabbit anti‐PBF antibody (LifeSpan BioSciences, LS‐C118942, Seattle, WA, USA) was used. SPSS 13.0 for Windows (SPSS Inc, Chicago, IL, USA) was used for all statistical analyses.ResultsHigh PBF expression was significantly correlated with age (P = 0·0298), distant metastases at diagnosis (P = 0·0139), tumour multicentricity (P = 0·0035), TNM stage (P = 0·0103), locoregional recurrence (P = 0·0410) and disease‐specific mortality (P = 0·0064). The expression level of PBF was significantly correlated with disease‐specific survival (P = 0·0065). Cox regression analysis showed that age, tumour size and PBF expression were independent prognostic indicators (P = 0·0097, P = 0·0021 and P = 0·0179).ConclusionPBF expression may be a promising biomarker for prognostic and therapeutic purpose. More large‐scale studies are needed to clarify its potential usefulness.
Determination of the uncertainty for the thermal conductivity obtained as a function of the moisture content for several foodstuffs
Authors: da Silva Wilton Pereira , e Silva Cleide M. D. P. S. , Precker Jürgen Wolfgang , Duarte Maria Elita Martins 
Published: August 2012

SummaryMany times, when an experimental result is communicated, the uncertainty is omitted, particularly in the case in which the parameter of interest is determined by curve fitting. This article presents a review study to include an uncertainty to the parameter of interest, obtained by fitting of a straight line to an experimental data set, supposing that systematic errors can be neglected. This study is applied to the determination of expressions for the thermal conductivity of food products, supposing a constant mean temperature. In this case, in general, the thermal conductivity is a linear function of the moisture content (wb). Expressions of the thermal conductivity were obtained for several foodstuffs, according to the recommendation of the International Organization for Standardization. Thus, for a given moisture content, the obtained expressions enable to determine the value for the thermal conductivity, as well as its uncertainty, for a stipulated confidence limit.
Antioxidant properties of different milk fermented with lactic acid bacteria and yeast
Authors: Parrella Alfredo , Caterino Emanuela , Cangiano Margherita , Criscuolo Emma , Russo Chiara , Lavorgna Margherita , Isidori Marina 
Published: August 2012

SummaryThe antioxidant properties of nine different samples of freshly drawn, pasteurised and UHT milk were examined before and after fermentation with several lactobacilli, individually and in combination with the yeast Saccharomyces boulardii. The results showed no statistical differences for the content in proteins, fats and carbohydrates of the different milk. The antioxidant properties of the unfermented milk were positively affected by the thermal treatment. All samples of fermented milk had a greater antioxidant activity than unfermented but only for the freshly drawn milk that increase was significantly different. The co‐incubation of lactobacilli with the yeast determined a stronger antioxidant activity especially for the freshly drawn milk. The stability of the tested strains during storage in standard conditions was determined in UHT fermented milk to enable a possible use in probiotic food production. The results showed that the yeast incubated with lactobacilli determined an improvement of the viability of bacteria.
Characterisation of pear distillates from wild and cultivated varieties in Sardinia
Authors: Versini Giuseppe , Franco Mario A. , Moser Sergio , Manca Gavina 
Published: August 2012

SummaryThe aroma fraction of Italian distillates of wild (Pyrus amygidaliformis, Vill., namely ‘Pirastru’) and cultivated (Pyrus communis, L. cvs. ‘Coscia’, ‘Precoce di Fiorano’ and ‘Butirru de Austu’) pear varieties grown in the northern part of the island of Sardinia was investigated. Distillates from fermented mashes were obtained from the same producer and, in most cases, for 3 years following the same production process. Aroma analyses were performed by GC‐FID and GC‐MS techniques with direct GC injection of full proof distillates. Differences were found in the aromatic profile of all the distillates depending on their varietal origin. Wild Pirastru pear distillates were the richest in isoeugenol (0.186 g hL−1 a.a.), ethyl benzoate (0.388 g hL−1 a.a.) and ethyl phenylacetate (0.12 g hL−1 a.a.) but the poorest in 1‐hexanol (2.69 g hL−1 a.a.), n‐hexyl acetate (0.07 g hL−1 a.a.), Σ‐farnesene isomers (0.80 g hL−1 a.a.) and citronellol (0.007 g hL−1 a.a.). Pirastru distillates were also the poorest in methyl and ethyl unsaturated decanoate isomers, the so‐called Williams pear esters (0.002 g hL−1 a.a.). On the contrary, these compounds that characterise the aroma of Williams pear distillates were abundant in Coscia spirits (1.032 g hL−1 a.a.). The latter, together with Precoce di Fiorano, were rich in farnesene isomers (6.48 and 9.26 g hL−1 a.a. respectively). Evaluation of the data by univariate (anova and Kruskal–Wallis) and multivariate (PCA and HCA) statistical analyses revealed that some components (the classes of acetates, farnesene isomers, methyl and ethyl unsaturated decanoate esters and citronellol) are relevant in discriminating the distillates according to variety.
Schistosoma real‐time PCR as diagnostic tool for international travellers and migrants
Authors: Cnops Lieselotte , Tannich Egbert , Polman Katja , Clerinx Jan , Van Esbroeck Marjan 
Published: August 2012

AbstractObjective  To evaluate the use of a genus‐specific PCR that combines high sensitivity with the detection of different Schistosoma species for diagnosis in international travellers and migrants in comparison to standard microscopy.Methods and results  The genus‐specific real‐time PCR was developed to target the 28S ribosomal RNA gene of the major human Schistosoma species. It was validated for analytical specificity and reproducibility and demonstrated an analytical sensitivity of 0.2 eggs per gram of faeces. Its diagnostic performance was further evaluated on 152 faecal, 32 urine and 38 serum samples from patients presenting at the outpatient clinic of the Institute of Tropical Medicine in Antwerp (Belgium). We detected Schistosoma DNA in 76 faecal (50.0%) and five urine (15.6%) samples of which, respectively, nine and one were not detected by standard microscopy. Only two of the 38 serum samples of patients with confirmed schistosomiasis were positive with the presently developed PCR. Sequence analysis on positive faecal samples allowed identification of the Schistosoma species complex.Conclusion  The real‐time PCR is highly sensitive and may offer added value in diagnosing imported schistosomiasis. The genus‐specific PCR can detect all schistosome species that are infectious to humans and performs very well with faeces and urine, but not in serum.
Mass administration of the antimalarial drug mefloquine to Guantánamo detainees: a critical analysis
Authors: Nevin Remington L. 
Published: August 2012

AbstractRecently, evidence has emerged from an unusual form of mass drug administration practised among detainees held at US Naval Station Guantánamo Bay, Cuba (‘Guantánamo’), ostensibly as a public health measure. Mefloquine, an antimalarial drug originally developed by the US military, whose use is associated with a range of severe neuropsychiatric adverse effects, was administered at treatment doses to detainees immediately upon their arrival at Guantánamo, prior to laboratory testing for malaria and irrespective of symptoms of disease. In this analysis, the history of mefloquine’s development is reviewed and the indications for its administration at treatment doses are discussed. The stated rationale for the use of mefloquine among Guantánamo detainees is then evaluated in the context of accepted forms of population‐based malaria control. It is concluded that there was no plausible public health indication for the use of mefloquine at Guantánamo and that based on prevailing standards of care, the clinical indications for its use are decidedly unclear. This analysis suggests the troubling possibility that the use of mefloquine at Guantánamo may have been motivated in part by knowledge of the drug’s adverse effects, and points to a critical need for further investigation to resolve unanswered questions regarding the drug’s potentially inappropriate use.