bluuebunny/crossref_metadata_2025 huggingface dataset:
Electroosmotic Flow Through a Circular Tube With Slip-Stick Striped Wall
Authors: Chu Henry C. W. , Ng Chiu-On
Published: October 2012

This is an analytical study on electrohydrodynamic flows through a circular tube, of which the wall is micropatterned with a periodic array of longitudinal or transverse slip-stick stripes. One unit of the wall pattern comprises two stripes, one slipping and the other nonslipping, and each with a distinct ζ potential. Using the methods of eigenfunction expansion and point collocation, the electric potential and velocity fields are determined by solving the linearized Poisson–Boltzmann equation and the Stokes equation subject to the mixed electrohydrodynamic boundary conditions. The effective equations for the fluid and current fluxes are deduced as functions of the slipping area fraction of the wall, the intrinsic hydrodynamic slip length, the Debye parameter, and the ζ potentials. The theoretical limits for some particular wall patterns, which are available in the literature only for plane channels, are extended in this paper to the case of a circular channel. We confirm that some remarks made earlier for electroosmotic flow over a plane surface are also applicable to the present problem involving patterns on a circular surface. We pay particular attention to the effects of the pattern pitch on the flow in both the longitudinal and transverse configurations. When the wall is uniformly charged, the adverse effect on the electroosmotic flow enhancement due to a small fraction of area being covered by no-slip slots can be amplified if the pitch decreases. Reducing the pitch will also lead to a greater deviation from the Helmholtz–Smoluchowski limit when the slipping regions are uncharged. With oppositely charged slipping regions, local recirculation or a net reversed flow is possible, even when the wall is on the average electropositive or neutral. The flow morphology is found to be subject to the combined influence of the geometry of the tube and the electrohydrodynamic properties of the wall.
Transparent conductive indium zinc oxide films prepared by pulsed plasma deposition
Authors: Wan Runlai , Yang Ming , Zhou Qianfei , Zhang Qun
Published: October 2012

Transparent conductive indium zinc oxide films were prepared by pulsed plasma deposition from a ceramic target (90 wt. % In2O3 and 10 wt. % ZnO). The dependences of film properties upon the substrate temperature was investigated using characterization methods including x-ray diffraction, atomic force microscope, Hall measurement, ultraviolet-visible spectroscopy, and x-ray photoelectron spectroscopy. The films grown at room temperature had a rather smooth surface due to the amorphous structure, with a root mean square roughness of less than 1 nm. The atomic ratio of Zn/(Zn + In) in these films is 15.3 at. %, which is close to that in the target, and the chemical states of indium and zinc atoms were In3+ and Zn2+, respectively. The films deposited on a substrate with a temperature of 200 °C exhibited polycrystalline structure and a preferred growth orientation along the (222) plane. Here the electrical properties were improved due to the better crystallinity, with the films exhibiting a minimum resistivity value of 4.2 × 10−4 Ω cm, a maximum carrier mobility of 45 cm2 V−1 s−1, and an optical transmittance over 80% in the visible region.
Fabrication of 5 Tdot/in.2 bit patterned media with servo pattern using directed self-assembly
Authors: Kihara Naoko , Yamamoto Ryousuke , Sasao Norikatsu , Shimada Takuya , Yuzawa Akiko , Okino Takeshi , Ootera Yasuaki , Kamata Yoshiyuki , Kikitsu Akira
Published: October 2012

The fabrication of an etching template for 5 Td/in.2 bit patterned media using a self-organization material, namely, poly(styrene)-poly(dimethylsiloxane) (PS-PDMS), was investigated. The molecular weight of the PS-PDMS for forming the areal density of 5 Td/in.2 dot pattern was estimated from the polymerization index related to the Flory–Huggins interaction parameter. Annealing was carried out to obtain a fine-order dot pattern. PS-PDMS films were subjected to thermal treatment or solvent annealing. The ordering of the dot array in these films was evaluated by using Voronoi diagrams. The results indicate that the film annealed in N-methylpyrrolidone (NMP) vapor showed finer ordering than did the thermally treated film. This seemed to be attributable to the high solubility parameter of NMP. The soaking of NMP into the PS phase slightly shifted the phase separation energy of the polymer matrix. The lattice spacing of the obtained hexagonal pattern was 11 nm. By using low-molecular-weight PS-PDMS with solvent annealing, a dot-array template for 5 Td/in.2 bit patterned media was formed.
The Effects of Acute and Chronic Stress on Diabetes ControlA Presentation from the European Society for Paediatric Endocrinology (ESPE) New Inroads to Child Health (NICHe) Conference on Stress Response and Child Health in Heraklion, Crete, Greece, 18 to 20 May 2012.
Authors: Marcovecchio M. Loredana , Chiarelli Francesco
Published: October 2012

Stress-induced hormonal changes alter glucose homeostasis in both diabetic and healthy patients.
PKR-Dependent Inflammatory Signals
Authors: Kang Rui , Tang Daolin
Published: October 2012

The RNA-dependent protein kinase activates the inflammasome to promote inflammation.
Disguised Cells Resist Therapy
Authors: Foley John F.
Published: October 2012

Proinflammatory cytokines cause tumor cells to lose the markers that make them targets of antitumor cytotoxic T cells.
Double dislocation of finger interphalangeal joints
Authors: Jahangiri Saqib Aziz , Mestha Prabhakar , McNally Scarlett
Published: October 2012

A 62-year-old, right-hand-dominant man who had dementia and lived in an Elderly Mentally Infirm (EMI) nursing home was admitted through Accident & Emergency (A&E) department following unwitnessed injury to the left little finger.

His examination revealed a swollen and deformed left little finger with a laceration along the middle crease on the volar aspect and head of proximal phalanx visible through this. Distally sensations and capillary refill was normal. X-rays showed a double dislocation of both proximal and distal interphalangeal joints. The finger was reduced under ring block and the laceration was washed with saline in A&E. The patient was taken to the operation theatre next morning for wound exploration and wash-out±stabilistion of the finger under general anaesthesia.

The wound was thoroughly washed out and closed with 4/0 interrupted nylon. The finger was immobilised with neighbour strapping and bandaged in flexion.
Laparoscopic management of interstitial pregnancy with automatic stapler
Authors: Ahsan Akhtar Muhammad , Izzat Feras , Keay Stephen D
Published: October 2012

A 36-year-old woman was referred by general practitioner to the early pregnancy unit with pelvic pain in her seventh week of pregnancy. She had a transvaginal ultrasound. Unruptured live twin tubal ectopic pregnancy was diagnosed on. Diagnostic laparoscopy revealed an unruptured left interstitial ectopic pregnancy. The interstitial tubal pregnancy was removed by laparoscopic automatic stapler with minimal blood loss. The patient had an uneventful recovery to health.
Inoperable bulky melanoma responds to neoadjuvant therapy with vemurafenib
Authors: Fadaki Niloofar , Cardona-Huerta Servando , Martineau Lea , Thummala Suresh , Cheng Shih-Tsung , Bunker Steve R , Garcia-Kennedy Richard , Wang Wei , Minor David , Kashani-Sabet Mohammed , Leong Stanley P L
Published: October 2012

A patient with a bulky inoperable stage IIIC melanoma involving the left axilla and neck from a primary of the left medial elbow received vemurafenib as neo-adjuvant treatment. Based on the molecular analysis, BRAF V600E mutation was present. After 4 months of vemurafinib treatment, the tumours shrank to less than 50% of original clinical size and allowed the surgeons to perform a left modified radical neck dissection and left radical axillary dissection. Pathological analysis of specimen revealed viable metastatic cells only in 1 of 40 nodes resected in the neck and axillary dissection, accounting for over 98% pathological response. Other lymph nodes had a mixture of foamy histiocytic inflammatory reaction fibrosis and islands of necrotic tissues. After recovery from surgery, vemurafenib was resumed and continued for 6 months. He remained disease free 6 months after surgery.
Brilliant crystallisation in the anterior chamber and subretinal space following adjunctive intravitreal ranibizumab for diabetic vitrectomy
Authors: Bastion Mae-Lynn Catherine , Mustapha Mushawiahti , Ho Ivan
Published: October 2012

To report a unique case of crystallisation in the anterior chamber and subretinal space in a Malay lady following inadvertent subretinal injection of ranibizumab prior to vitrectomy for proliferative diabetic retinopathy.
Oxidative stress and cancer pain
Authors: Ungard Robert G. , Seidlitz Eric P. , Singh Gurmit
Published: October 2012

Breast cancers are the most common source of metastases to bone, of which cancer-induced bone pain is a frequent pathological feature. Cancer-induced bone pain is a unique pain state with multiple determinants that remains to be well understood and managed. Current standard treatments are limited by dose-dependent side effects that can reduce the quality of life of patients. Glutamate is a neurotransmitter and bone cell-signalling molecule that is released via the system [Formula: see text] cystine/glutamate antiporter from cancer cell types that frequently metastasize to bone, including breast cancers. In cancer cells, glutamate release is understood to be a side effect of the cellular response to oxidative stress that upregulates the expression and activity of system [Formula: see text] to promote the increased import of cystine. Attenuation of glutamate release from cancer cells has been demonstrated to result in reductions in associated cancer-induced bone pain in animal models. This review examines the clinical implications of attenuating cystine uptake and glutamate release in the treatment of cancer-induced bone pain.
Hemagglutinating activity is directly correlated with colonization ability of shigellae in suckling mouse model
Authors: Mitra Soma , Saha Dhira Rani , Pal Amit , Niyogi Swapan Kumar , Mitra Utpala , Koley Hemanta
Published: October 2012

The aim of the present study was to explore a new approach based on the hemagglutination (HA) assay to understand the colonization ability of Shigella spp. To study colonization ability, an animal model of 4-day-old suckling mouse, was exploited. We characterized the HA activity of 48 Shigella strains, with erythrocytes collected from rabbit, guinea pig, chicken, and sheep. Only rabbit and guinea pig erythrocytes showed positive HA reactions in most of the cases. On the basis of HA pattern, 4 strains from each serogroup were selected for in vivo colonization studies. Our results showed a positive correlation between HA activity and colonization ability of the strains belonging to different serogroups (groups A, B, C, and D) of Shigella. In all 4 serogroups, high HA titer was associated with greater intestinal colonization.
Improved methods for axenic culture of Labyrinthula terrestris, causal agent of rapid blight of turfgrasses
Authors: Yadagiri Kirthi Kiran , Kerrigan Julia , Martin S. Bruce
Published: October 2012

The genus Labyrinthula is a group of unicellular microorganisms with spindle-shaped cells that move in an ectoplasmic network. Most Labyrinthula species are saprotrophic and found in coastal marine or estuarine habitats; however, exceptions exist, such as Labyrinthula terrestris , a terrestrial plant pathogen that causes rapid blight on cool-season turfgrasses. Labyrinthula spp. can be grown in culture, which facilitates studies on their biology and pathology. However, axenic culture of L. terrestris has always been challenging. We modified the most commonly used Labyrinthula growth medium, serum seawater agar (SSA), and designed 2 media for improved pure culture, modified SSA (MSSA) and grass extract SSA (GESSA). A comparative assessment of these 2 media and basic SSA was made to measure the growth responses of 18 L. terrestris isolates. Results indicate that the average colony area was greatest on GESSA followed by MSSA, while cultures lived longest on MSSA followed by GESSA. We also suggest an improved long-term culture technique to maintain viable L. terrestris isolates for at least 2 years.
An investigation into plasmolysis in the oomyceteAchlya bisexualisreveals that membrane–wall attachment points are sensitive to peptides containing the sequence RGD and that cell wall deposition can occur despite retraction of the protoplast
Authors: Chitcholtan Kenny , Harris Elisa , Yu YuPing , Harland Chad , Garrill Ashley
Published: October 2012

The structure and function of membrane–wall attachment sites in walled cells, and how these relate to animal focal adhesions, is an area that is poorly understood. In view of this, we investigated how membrane–wall attachments that form upon plasmolysis, respond to peptides that disrupt animal focal adhesions. The degree of cytoplasmic disruption during plasmolysis was also investigated. Upon hyperosmotic challenge, the protoplast in hyphae of the oomycete Achlya bisexualis typically retracted incompletely due to membrane–wall attachments. The inclusion, in the plasmolysing solution, of peptides containing the sequence RGD disrupted these attachments in a dose-dependent manner. In some hyphae, protoplast retraction stopped temporarily at attachment points — upon resumption of retraction, material was left that traced the outline of the static protoplast. Staining of this material with fluorescence brightener indicated the presence of cellulose, which suggests that wall deposition was able to occur despite plasmolysis. The F-actin cytoskeleton was disrupted during plasmolysis; peripheral F-actin staining was observed, but there was no distinct F-actin cap; staining was more diffuse; and there were fewer plaques compared with nonplasmolysed hyphae. Our data indicate that membrane–wall attachment points are sensitive to RGD-containing peptides and that wall deposition continues despite protoplast retraction and F-actin disruption.
NON-STANDARD HIGGS AND mh≃125 GeV
Authors: ENGLERT CHRISTOPH
Published: October 2012

We review non-Standard Model Higgs signatures which are missed in standard analyses by both ATLAS and CMS and show how the strong bounds by recent measurements can be relaxed in strongly-interacting theories. We also review strategies how to measure or constrain exotic Higgs decay at the LHC and a future linear collider.
Effects of Surface Temperature on High-Rate Etching of Silicon by Narrow-Gap Microwave Hydrogen Plasma
Authors: Yamada Takahiro , Ohmi Hiromasa , Okamoto Kohei , Kakiuchi Hiroaki , Yasutake Kiyoshi
Published: October 2012

Effects of surface temperature on high-rate etching of Si by narrow-gap microwave hydrogen plasma have been investigated. The etch rate strongly depended on the surface temperature. The optimum temperature for the etching at high rate was about 70 °C. With increasing the temperature higher than 70 °C, decrease in etch rate was observed, and activation energy for the reaction process was estimated to be about -1.8 kcal/mol. This value agreed well with the result of the previous studies using low-pressure plasma conditions. In addition, hydrogen concentration was also affected by the surface temperature. The reduction in hydrogen concentration near the surface was observed in the etched sample at higher temperature. From these results, reaction mechanism causing the decrease in etch rate with the temperature increase has been discussed in terms of both desorption and in-diffusion of hydrogen from the surface.
Wettability and Reaction between Solder and Silver Busbar during the Tabbing Process for Silicon Photovoltaic Modules
Authors: Lee Beom-Yong , Hoang Thi-Lien , Cho Sung-Bin , Huh Joo-Youl , Lee Young-Sik
Published: October 2012

The soldering quality of a Cu ribbon onto the Ag busbars of solar cells is one of the key factors affecting the cell-to-module loss and durability of a silicon photovoltaic module. In this study, we examined the effects of the surface chemistry and morphology of the screen-printed Ag busbars on the solder wettability and bonding uniformity of the Cu ribbon over the length of the busbar during the tabbing process. The surface of the as-fired Ag busbar was covered by a thin glass layer originating from the glass frit contained in the Ag paste. The presence of the thin glass layer significantly decreased the wettability of the solder, leading to the formation of voided regions at the solder/busbar interface. Although it had only a minor influence on solder wettability, increasing the roughness of the busbar surface resulted in the formation of more voided regions at the solder/busbar interface.
Effect of the Low-Temperature Annealing on Zn-Doped Indium–Tin-Oxide Films for Silicon Heterojunction Solar Cells
Authors: Lee Seunghun , Lee Jong-Han , Tark Sung Ju , Choi Suyoung , Kim Chan Seok , Lee Jeong Chul , Kim Won Mok , Kim Donghwan
Published: October 2012

The effects of the low-temperature annealing on Zn-doped indium–tin-oxide (ITO) films such as the electrical, optical and structural properties were investigated. Zn-doped ITO films were fabricated by rf magnetron sputtering of ITO and Al-doped ZnO (AZO) targets on corning glass at room temperature. The content of Zn increased with increasing the power of AZO target. The carrier concentration of films shows the decreasing behaviour with increasing the content of Zn, due to a carrier compensation originating from the substitution of a doped Zn for an In or interstitial site. After the low-temperature annealing at 180 °C in vacuum, all films were slightly decreased a carrier concentration and increased the hall mobility because of the absorption of oxygen on the surface films. In addition, the average transmittance did not show a considerable change and had a high values over 80%. Especially, the Zn-doped ITO with atomic ratio of Zn/(In+Zn) of 6.8 at. % had the resistivity of 4×10-4 Ω cm, the highest hall mobility of 41 cm2 V-1 s-1, and the average transmittance of 82%.
Mapping Characterization of SnO2:F Transparent Conductive Oxide Layers by Ellipsometry Technique
Authors: Sago Yuichiro , Fujiwara Hiroyuki
Published: October 2012

The mapping characterization for the structural and optoelectronic properties of textured SnO2:F transparent conductive oxide (TCO) layers has been performed by spectroscopic ellipsometry (SE). From the SE analysis of the free carrier absorption in the SnO2:F layer, the optical carrier concentration and mobility are extracted by using the Drude model. As a result, in the textured SnO2:F substrate with a size of 9×9 cm2, we have confirmed slight non-uniformities in the carrier concentration as well as the layer thickness. Moreover, in order to investigate the effect of the TCO inhomogeneity on hydrogenated amorphous silicon (a-Si:H) and microcrystalline silicon (µc-Si:H) tandem solar cells, we have simulated short-circuit current density (J
sc) in the a-Si:H and µc-Si:H layers by taking the TCO inhomogeneity into account using the optical admittance method. From this procedure, we have quantitatively estimated the variation of J
sc by the TCO inhomogeneity assuming a non-textured flat structure.
Development of Boron-Doped ZnO Films with Novel Thin Zn-Rich Film and Their Application to Solar Cells
Authors: Hongsingthong Aswin , Wada Hidetoshi , Moriya Yuki , Sichanugrist Porponth , Konagai Makoto
Published: October 2012

In this paper, we report newly developed high-haze glass/zinc oxide (ZnO) substrates with low resistivity by a combination of unique etched soda-lime glass and bilayered ZnO films with a Zn-rich (oxygen-poor) layer. The high mobility and low resistivity of bilayered ZnO films could be obtained with Zn-rich conditions. By depositing the ZnO films onto textured glass substrates, the obtained films exhibit an excellent light-scattering property, while their electrical property is still good. Furthermore, the bilayered ZnO films with a Zn-rich layer did not negatively affect the transparency of the films. Employing the bilayered ZnO films with a Zn-rich layer and an rms roughness of about 274 nm as the front transparent conductive oxide (TCO) in hydrogenated amorphous silicon (a-Si:H) solar cells, we improved the performance and quantum efficiency (QE) of the fabricated solar cells, particularly in the short-wavelength region without the deterioration of open-circuit voltage or fill factor. Thus, the developed glass/bilayered ZnO film with a Zn-rich layer is a new promising material since its resistivity is low while its light-scattering property is still high.
Development of Novel Aluminum-Doped Zinc Oxide Film and Its Application to Solar Cells
Authors: Kuramochi Hideto , Akiike Ryo , Iigusa Hitoshi , Tamano Kimiaki , Utsumi Kentaro , Shibutami Tetsuo , Sichanugrist Porponth , Konagai Makoto
Published: October 2012

We have developed novel aluminum-doped zinc oxide films (AZO-X and AZO-HX films) with a high haze value using wet-chemical etching for various times after dc magnetron sputtering, and have investigated their electrical and optical properties, durability under high-humidity condition, and surface morphology. The AZO-X and AZO-HX films showed good balance between transmittance in the near-infrared area and durability under 85 °C–85%RH condition. These novel films also had a higher haze value after wet chemical etching than normal AZO films. The crater size and haze value of the AZO-HX film increased with increasing etching time in comparison with those of the AZO-X film. The haze value of the AZO-HX film was higher than that of the AZO-X film; their values are 90% at 550 nm and 60% at 800 nm. Furthermore, the AZO-HX film was applied in amorphous silicon (a-Si) single-type solar cells as the front electrode. The short-circuit current of the solar cell using the AZO-HX film was higher than that of the solar cell using the AZO-X film. As an optimization-based result, an efficiency as high as 10.2% was obtained, showing that the new AZO-HX film is a promising material for the front electrode of a-Si solar cells.
Synthesis, Properties, and Photovoltaic Performance of Copolymers Based on Difluorodioxocyclopentene-Annelated Thiophene
Authors: Ie Yutaka , Huang Jianming , Uetani Yasunori , Karakawa Makoto , Aso Yoshio
Published: October 2012

New π-conjugated polymers containing difluorodioxocyclopentene-annelated thiophenes as an electron-accepting unit have been synthesized for application to p-type organic semiconducting materials in organic photovoltaics. The photophysical and electrochemical properties of these polymers were investigated by UV–vis absorption spectra and cyclic voltammetry measurements. The carrier mobility measurement of the copolymer on organic field-effect transistor devices revealed p-channel behavior. Bulk heterojunction photovoltaic devices made from blends of the polymer and [6,6]-phenyl-C71-butyric acid methyl ester showed moderate photovoltaic characteristics with a power conversion efficiency of 0.77%.
Effects of Antimony Doping in Polycrystalline CdTe Thin-Film Solar Cells
Authors: Okamoto Tamotsu , Ikeda Shigeyuki , Nagatsuka Satsuki , Hayashi Ryoji , Yoshino Kaoru , Kanda Yohei , Noda Akira , Hirano Ryuichi
Published: October 2012

The effects of antimony (Sb) doping of the CdTe layer in the CdTe solar cells were investigated using Sb-doped CdTe powders as source materials for CdTe deposition by the close-spaced sublimation (CSS) method. Conversion efficiency increased with increasing Sb concentration below 1×1018 cm-3, mainly owing to the improvement of the fill factor. Secondary ion microprobe mass spectrometry (SIMS) depth profile revealed that the Sb impurities at a concentration of approximately 1×1016 cm-3 were incorporated into the CdTe layer when using the Sb-doped CdTe source of 1×1018 cm-3. The observation of surface morphology showed that the grain sizes were improved by Sb addition. Therefore, the improved performance upon Sb addition to CdTe solar cells was probably due to the improvements in crystallinity, such as increased grain size.
Dependence of the Properties of Cu(In,Ga)S2/Mo Films Prepared by Two-Stage Evaporation Method on Degree of Vacuum during Deposition
Authors: Kaigawa Ryuji , Souza Diogo M. , Satake Yasuhiro , Klenk Reiner
Published: October 2012

The influence of background pressure in multisource evaporation is not straightforward to explain, but it is clear that the amount of absorbed gases on the surface of the growing grains change with pressure. This may influence surface energies, and consequently the growth mechanism. We investigated the relation between the orientation of Cu(In,Ga)S2 films and pressure during deposition. We varied the background pressure during the deposition of the precursor film (first stage) by varying the temperature of the sulphur source, by throttling the vacuum pump, or by introducing N2 gas. We found that Cu(In,Ga)S2 films prepared from In–Ga–S precursors show (112) orientation if the pressure during precursor deposition is less than 0.03 Pa when the pressure is mainly attributable to sulphur. When it is mainly due to N2 gas, the pressure at which the orientation changes is 0.14 Pa. The orientation of the final film reflects the orientation of the (In,Ga)2S3 precursor immediately before entering the second stage.
Effect of H2S Annealing on Sb-Doped Cu–In–S Thin Films Prepared by Vacuum Evaporation
Authors: Akaki Yoji , Yamazumi Noriyuki , Nakamura Shigeyuki , Tokuda Takahiro , Yoshino Kenji
Published: October 2012

We investigated the effect of H2S annealing on Sb-doped Cu–In–S thin films prepared using a vacuum evaporation method. These CuInS2 thin films were grown successfully when annealed above 350 °C in H2S atmosphere. It was found that the thin films were closer to stoichiometry at lower annealing temperatures compared with the undoped thin films. The carrier concentrations, resistivities and mobilities of Sb-doped thin films annealed at 400 °C were approximately 1×1018 cm-3, 30 Ω cm, and 1 cm2 V-1 s-1, respectively.
Spray-Pyrolyzed Three-Dimensional CuInS2Solar Cells on Nanocrystalline-Titania Electrodes with Chemical-Bath-Deposited Inx(OH)ySzBuffer Layers
Authors: Nguyen Duy-Cuong , Mikami Yuki , Tsujimoto Kazuki , Ryo Toshihiro , Ito Seigo
Published: October 2012

Three-dimensional (3D) compound solar cells with the structure of  have been fabricated by spray pyrolysis deposition of CuInS2and chemical-bath deposition of Inx(OH)ySzfor the light absorber and buffer layer, respectively. The effect of deposition and annealing conditions of Inx(OH)ySzon the photovoltaic properties of 3D CuInS2solar cells was investigated. Inx(OH)ySzannealed in air ambient showed a better cell performance than those annealed in nitrogen ambient and without annealing. The improvement of the performance of cells with Inx(OH)ySzbuffer layers annealed in air ambient is due to the increase in oxide concentration in the buffer layers [confirmed by X-ray photoelectron spectroscopy (XPS) measurement]. Among cells with Inx(OH)ySzbuffer layers deposited for 1, 1.5, 1.75, and 2 h, that with Inx(OH)ySzdeposited for 1.75 h showed the best cell performance. The best cell performance was observed for Inx(OH)ySzdeposited for 1.75 h with annealing at 300 °C for 30 min in air ambient, and cell parameters were 22 mA cm-2short-circuit photocurrent density, 0.41 V open-circuit voltage, 0.35 fill factor, and 3.2% conversion efficiency.
Synthesis and Characterization of Wurtzite Cu2ZnSnS4 Nanocrystals
Authors: Jao Meng-Huan , Liao Hsueh-Chung , Wu Ming-Chung , Su Wei-Fang
Published: October 2012

Copper–zinc–tin–chalcogenide (CZTSSe) with earth abundant elements has attracted increasing attention due to large absorption coefficient and band gap of ∼1.5 eV which is near the optimum band gap of single-junction photovoltaic devices. In this study, we used commercially available precursors to produce wurtzite Cu2ZnSnS4 nanocrystals by simple solvothermal synthesis. Different from the typical kesterite or stannite phases of CZTS, the nanocrystals synthesized in this study are in wurtzite phase with hexagonal crystal cell. The n-dodecanethiol was used to control the reactivity of metal ions, leading to the controlled size of CZTS nanoparticle by simply varying the reaction time. Furthermore, the as synthesized CZTS nanocrystals have novel wurtzite crystal structure. As a result, a red shift of absorption band edge between the CZTS nanoparticles with different size was obtained. Our study provides an extending method of CZTS nanocrystal ink preparation awaiting for further photovoltaic device application.
ZnInS Thin Film Solar Cell Fabricated by Sputtering Process
Authors: Deguchi Hiroshi , Miura Hiroshi , Tsuji Kazuaki , Yuzurihara Hajime
Published: October 2012

To achieve low cost solar cells, new fabrication processes should be developed for higher throughput and utilization rate. In this study, we focused on a sputtering method and found that a multinary compound ZnInS (II–III–VI) is suitable for this process. The ZnInS thin film deposited by sputtering had an n-type semiconductor characteristic. A AgInTe/ZnInS thin-film solar cell fabricated by the sputtering process in a layer structure of glass/Mo/AgInTe/ZnInS/AZO showed a conversion efficiency of over 1%, the origin of which was mainly the ZnInS layer. These results suggested that ZnInS is a strong candidate photovoltaic material for fabrication with the sputtering process.
Barrier Thickness Dependence of Photovoltaic Characteristics of InGaN/GaN Multiple Quantum Well Solar Cells
Authors: Watanabe Noriyuki , Yokoyama Haruki , Shigekawa Naoteru , Sugita Ken-ichi , Yamamoto Akio
Published: October 2012

We discuss the influence of the barrier thickness of an InGaN/GaN multiple quantum well (MQW) structure on solar cell performance. As barrier thickness decreases, short-circuit current density increases and open-circuit voltage decreases. The open-circuit voltage is much lower than expected from the absorption edge because of the large leakage current and large ideality factor of diodes owning to the carrier tunneling through the barrier. An MQW with a 3-nm-thick barrier layer shows a much longer carrier lifetime than that with a 9-nm-thick barrier layer. This is one possible reason for a higher short-circuit current in solar cell with the 3-nm-thick barrier MQW structure than that with the 9-nm-thick barrier MQW.
Fabrication of Monolithic Integrated Series-Connected GaAs Photovoltaic Cells for Concentrator Applications
Authors: Watanabe Kentaroh , Yamada Yugo , Senou Minato , Sugiyama Masakazu , Nakano Yoshiaki
Published: October 2012

Aiming at reducting in Joule energy loss of a photovoltaic cell under sunlight concentration, monolithic integration of GaAs cells has been realized, in which five subcells were connected in series and the total surface area of the cells occupied over 80% of the whole chip area. Using plasma etching with Cl2, a sufficiently sharp mesa for device isolation was obtained. Insulation between etched mesa sidewalls and interconnect electrodes proved to be the most significant issues for the purpose of eliminating shunt resistance and securing a reasonable fill factor; the SiO2 layer deposited by sputtering was much superior to polyimide as an insulator. The fabricated test device showed a short circuit current density of 20.7 mA/cm2 and an open circuit voltage of 4.79 V, which were consistent with the values for a single subcell.
Polymer-Sensitized Solar Cells Using Polythiophene Derivatives with Directly Attached Carboxylic Acid Groups
Authors: Akitsu Kenta , Kubo Takaya , Uchida Satoshi , Segawa Hiroshi , Otani Naoki , Tomura Misayo , Tamura Takayuki , Matsumura Mitsunobu
Published: October 2012

Polythiophene derivatives with carboxylic acid groups directly attached to the thiophene rings were synthesized for polymer-sensitized solar cells (PSSCs). The polymer layer densely and uniformly covering the surface of the TiO2 particle in the photoanode of the PSSCs allows excitons to diffuse to the polymer/TiO2 interface efficiently. The PSSCs yielded a maximum incident photon-to-current conversion efficiency of about 80% at 480 nm and the open-circuit voltage (V
OC) values but also short-circuit current density (J
SC) values increased with decreasing hydrolysis ratio of the polymer.
Numerical Approach to the Performance of Silicon Quantum Dots Superlattice Solar Cells Taking into Account the Quantum Effect
Authors: Kurokawa Yasuyoshi , Yamada Shigeru , Konagai Makoto
Published: October 2012

The electrical characteristics of silicon quantum dot superlattice (Si-QDSL) solar cells have been investigated using a two-dimensional (2D) device simulator, taking the quantum size effect into account. The average bandgap of a Si-QDSL embedded in an amorphous silicon oxycarbide (a-SiO
x
C
y
: E
g=2.5 eV) matrix increased from 1.21 to 1.75 eV with decreasing diameter of Si QDs from 10 to 3 nm owing to the quantum size effect. It should be noted that the V
oc of Si-QDSL solar cells also increased to 1.11 V with decreasing diameter of Si QDs to 3 nm. This result indicates that it is possible to enhance V
oc by the quantum size effect and that a Si-QDSL may be a promising material for all-silicon tandem solar cells.
Surface Treatment for Effective Dye Adsorption on Nanocrystalline TiO2
Authors: Yanagida Masatoshi , Han Chen , Han Liyuan
Published: October 2012

To improve the efficiency of dye-sensitized solar cells (DSCs) by controlling dye adsorption on TiO2 surface, the effect of surface treatments on the properties of [NBu4]2[Ru(Htcterpy)(NCS)3] (black dye; [NBu4]: tetrabutylammonium cation; H3tcterpy: 4,4',4''-tricarboxy-2,2':6',2''-terpyridine) on nanocrystalline TiO2 films was investigated by analysis of the photovoltaic performance and the electron transport properties. Although the surface treatments do not affect on the condition band edge of TiO2, the amount of dye on TiO2 increases. The enhancement of dye adsorption by treatment of TiO2 in HCl solution is more effective than that by dipping the dye solution containing deoxycholic acid (DCA) as additive. But the charge recombination between an electron in TiO2 and I3
- in the electrolyte can be reduced by the DCA treatment.
Effect of Cu2O Doping in TiO2Films on Device Performance of Dye-Sensitized Solar Cells
Authors: Koo Horng-Show , Wang Der-Tsuey , Yu Yi-Kuei , Ho Shao-Hung , Jhang Jia-Yu , Chen Mi , Tai Ming-Fong
Published: October 2012

We demonstrated the effects of Cu2O doping at various weight ratios in TiO2photoanode films on the photovoltaic performance of dye-sensitized solar cells (DSSCs). The photovoltaic characteristics, namely, open-circuit voltage, short-circuit current, fill factor, and energy conversion efficiency, of DSSCs with 0.3 wt % Cu2O doping in the photoanode are 690 mV, 4.55 mA/cm2, 52.0%, and 1.96%, respectively. The photovoltaic parameters of the sample with 0.3 wt % Cu2O doping are better than those of other Cu2O-doped samples, which are inferior to undoped TiO2-based DSSCs. The measured cell performance shows that the addition of Cu2O to the TiO2photoanode in DSSCs results in the reduction of photovoltaic parameters. The degradation mechanism upon Cu2O doping in the TiO2photoanode of DSSCs may be attributed to the variations in the valence numbers of copper and titanium ions during calcination and the reduction–oxidation reaction, resulting in the formation of oxygen vacancy–Ti+3defects and related recombination centers.
Co-Electrophoretic Deposition Multiwall Carbon Nanotubes/Pt Counter Electrodes for Dye-Sensitized Solar Cell
Authors: Maiaugree Wasan , Pimanpang Samuk , Towannang Madsakorn , Rutphonsan Phikun , Laupa Seksan , Jarernboon Wirat , Amornkitbamrung Vittaya
Published: October 2012

Multiwall carbon nanotubes (MWCNTs) and platinum (Pt) were coated on fluorine doped tin oxide (FTO) coated glass by a direct current electrophoretic method, and were used as dye-sensitized solar cell counter electrodes. Scanning electron microscopy (SEM) detected the deposition of carbon nanotubes on FTO-glass. The deposition of Pt nanoparticles on carbon nanotube surfaces was confirmed by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Cell efficiencies of MWCNTs, Pt and MWCNTs/Pt dye-sensitized solar cells (DSSCs) were ∼1.41, ∼8.13, and ∼8.90%, respectively. The improvement of the composited MWCNTs/Pt cell efficiency is due to the presence of both catalysts (MWCNTs and Pt) enhancing counter electrode catalytic activity as observed by cyclic voltammetry (CV) and reducing charge-transfer resistance as observed by electrochemical impedance spectroscopy (EIS).
Photovoltaic Properties of Solar Cells Based on Poly(methyl phenyl silane) and C60
Authors: Mizuno Toya , Akasaka Yumeno , Tachibana Hiroaki
Published: October 2012

Photovoltaic (PV) devices using blend films of poly(methyl phenyl silane) (PMPS) and fullerene (C60) are fabricated, and the effects of various technical parameters during device fabrication on the PV characteristics under AM 1.5G simulated solar light illumination of 100 mW/cm2 intensity are investigated. The PV performance of the devices depends on the mixing ratio of PMPS:C60, the kind of buffer layer, the thickness of the buffer layer, and the thermal annealing temperature of the devices. The devices optimized for the mixing ratio, kind of buffer layer, and thermal annealing temperature exhibit a short-circuit current density (J
SC) of 2.26 mA/cm2, an open circuit voltage (V
OC) of 0.71 V, a fill factor (FF) of 0.35, and a power conversion efficiency (PCE) of 0.57%.
Tuning of Fullerene Materials for Organic Solar Cells: A Theoretical Study on the Properties of Defect Fullerenes C59 and C69
Authors: Tokunaga Ken , Ohmori Shigekazu , Kawabata Hiroshi
Published: October 2012

Hole transport and other fundamental properties of defect fullerenes C59 and C69 were investigated using density functional theory calculations. C59 and C69 isomers without a four-membered ring and three neighboring five-membered rings are generally stable. Formation of a carbon vacancy in C60 and C70 slightly increases the highest occupied molecular orbital energy and greatly decreases the lowest unoccupied molecular orbital energy, so that the energy gap decreases by 1 eV. The reorganization energies of all defect fullerenes are larger than those of the original C60 and C70 because of the localization of injected carriers around the vacancy. The reorganization energy of defect fullerenes is closely related to relaxation of the C–C bond of unsaturated C atoms.
Maximum Output Power Control Using Short-Circuit Current and Open-Circuit Voltage of a Solar Panel
Authors: Kato Takahiro , Miyake Takuma , Tashima Daisuke , Sakoda Tatsuya , Otsubo Masahisa , Hombu Mitsuyuki
Published: October 2012

A control method to optimize the output power of a solar cell is necessary because the output of a solar cell strongly depends on solar radiation. We here proposed two output power control methods using the short-circuit current and open-circuit voltage of a solar panel. One of them used a current ratio and a voltage ratio (αβ control), and the other used a current ratio and a short-circuit current–electric power characteristic coefficient (αγ control). The usefulness of the αβ and the αγ control methods was evaluated. The results showed that the output power controlled by our proposed methods was close to the maximum output power of a solar panel.
Origin of Anisotropic Electrical Properties of 4H-SiC Trench Metal–Oxide–Semiconductor Field-Effect Transistors on Off-Axis Substrates
Authors: Ueoka Yoshihiro , Shingu Kenta , Yano Hiroshi , Hatayama Tomoaki , Fuyuki Takashi
Published: October 2012

The origin of anisotropic electrical properties on 4H-SiC trench metal–oxide–semiconductor field-effect transistors (MOSFETs) with large off-axis angles has been discussed from the viewpoints of charge pumping current and surface roughness. The channel mobility (µch) on (112̄0) tilted toward [0001̄] was high and that on (1̄1̄20) tilted toward [0001] was low. The roughness at the SiC/SiO2 interfaces was measured after the removal of the oxide. A rough surface was observed on (1̄1̄20). A locally thick gate oxide results in a nonuniform inversion layer, which is the main origin of the anisotropic electrical properties of the trench MOSFETs on off-axis substrates.
Intrinsic Inter- and Intraspecific Competition in Parasitoid Wasps
Authors: Harvey Jeffrey A. , Poelman Erik H. , Tanaka Toshiharu
Published: October 2012

Immature development of parasitoid wasps is restricted to resources found in a single host that is often similar in size to the adult parasitoid. When two or more parasitoids of the same or different species attack the same host, there is competition for monopolization of host resources. The success of intrinsic competition differs between parasitoids attacking growing hosts and parasitoids attacking paralyzed hosts. Furthermore, the evolution of gregarious development in parasitoids reflects differences in various developmental and behavioral traits, as these influence antagonistic encounters among immature parasitoids. Fitness-related costs (or benefits) of competition for the winning parasitoid reveal that time lags between successive attacks influence the outcome of competition. Physiological mechanisms used to exclude competitors include physical and biochemical factors that originate with the ovipositing female wasp or her progeny. In a broader multitrophic framework, indirect factors, such as plant quality, may affect parasitoids through effects on immunity and nutrition.
Host Responses in Tissue Repair and Fibrosis
Authors: Duffield Jeremy S. , Lupher Mark , Thannickal Victor J. , Wynn Thomas A.
Published: October 2012

Myofibroblasts accumulate in the spaces between organ structures and produce extracellular matrix (ECM) proteins, including collagen I. They are the primary “effector” cells in tissue remodeling and fibrosis. Previously, leukocyte progenitors termed fibrocytes and myofibroblasts generated from epithelial cells through epithelial-to-mesenchymal transition (EMT) were considered the primary sources of ECM-producing myofibroblasts in injured tissues. However, genetic fate mapping experiments suggest that mesenchyme-derived cells, known as resident fibroblasts, and pericytes are the primary precursors of scar-forming myofibroblasts, whereas epithelial cells, endothelial cells, and myeloid leukocytes contribute to fibrogenesis predominantly by producing key fibrogenic cytokines and by promoting cell-to-cell communication. Numerous cytokines derived from T cells, macrophages, and other myeloid cell populations are important drivers of myofibroblast differentiation. Monocyte-derived cell populations are key regulators of the fibrotic process: They act as a brake on the processes driving fibrogenesis, and they dismantle and degrade established fibrosis. We discuss the origins, modes of activation, and fate of myofibroblasts in various important fibrotic diseases and describe how manipulation of macrophage activation could help ameliorate fibrosis.
Chloride in Vesicular Trafficking and Function
Authors: Stauber Tobias , Jentsch Thomas J.
Published: October 2012

Luminal acidification is of pivotal importance for the physiology of the secretory and endocytic pathways and its diverse trafficking events. Acidification by the proton-pumping V-ATPase requires charge compensation by counterion currents that are commonly attributed to chloride. The molecular identification of intracellular chloride transporters and the improvement of methodologies for measuring intraorganellar pH and chloride have facilitated the investigation of the physiology of vesicular chloride transport. New data question the requirement of chloride for pH regulation of various organelles and furthermore ascribe functions to chloride that are beyond merely electrically shunting the proton pump. This review surveys the currently established and proposed intracellular chloride transporters and gives an overview of membrane-trafficking steps that are affected by the perturbation of chloride transport. Finally, potential mechanisms of membrane-trafficking modulation by chloride are discussed and put into the context of organellar ion homeostasis in general.
Semiconductor Quantum Dots Surface Modification for Potential Cancer Diagnostic and Therapeutic Applications
Authors: Wang Jidong , Han Shumin , Ke Dandan , Wang Ruibing
Published: October 2012

Semiconductor Quantum dots (QDs) have generated extensive interest for biological and clinical applications. These applications arise from their unique properties, such as high brightness, long‐term stability, simultaneous detection of multiple signals, tunable emission spectra. However, high‐quality QDs, whether single or core‐shell QDs, are most commonly synthesized in organic solution and surface‐stabilized with hydrophobic organic ligands and thus lack intrinsic aqueous solubility. For biological applications, very often it is necessary to make the QDs dispersible in water and therefore to modify the QD surfaces with various bifunctional surface ligands or caps to promote solubility in aqueous media. Well‐defined methods have been developed for QD surface modification to impart biocompatibility to these systems. In this review, we summarize the recent progress and strategies of QDs surface modification for potential cancer diagnostic and therapeutic applications. In addition, the question that arose from QD surface modification, such as impact of size increase of QD bioconjugates after surface‐functionalization or surface modification on photophysical properties of QDs, are also discussed.
Prevalence and Antimicrobial Resistance of ThermophilicCampylobacterIsolated from Chicken in Côte d’Ivoire
Authors: Gblossi Bernadette Goualié , Eric Essoh Akpa , Elise Solange Kakou-N'Gazoa , Natalie Guessennd , Souleymane Bakayoko , Lamine Sébastien Niamké , Mireille Dosso
Published: October 2012

ThermophilicCampylobactersare major causes of gastroenteritis in human. The main risk factor of infection is consumption of contaminated or by cross-contaminated poultry meat. In Côte d’Ivoire, gastroenteritis is usually observed but no case of human campylobacteriosis has been formally reported to date. The aims of this study were to determine prevalence and antimicrobial resistance ofCampylobacter jejuniandCampylobacter coliisolated from chickens ceaca in commercial slaughter in Abidjan. Between May and November 2009, one hundred and nineteen (119) chicken caeca samples were collected and analyzed by passive filtration method followed by molecular identification (PCR). From these 119 samples, 76 (63.8%) were positive toCampylobactertests. Among the positive colonies, 51.3% wereC. jejuniand 48.7% wereC. coli. Of the 39C. jejuniisolates, 79.5%, 38.5%, 17.9%, 10.3%, and 7.7% were, respectively, resistant, to nalidixic acid, ciprofloxacin, amoxicillin, erythromycin, and gentamicin. Among the 37 isolates ofC. coli, 78.4%, 43.2%, 13.5%, 8.1%, and 0% were resistant, respectively, to the same antibiotics. In conclusion, we reported in this study the presence of highCampylobactercontamination of the studied chickens. Molecular identification of the bacteria was performed and determination of high resistance to antimicrobials of the fluoroquinolone family was revealed.