bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stress test measurements of lattice‐matched InAlN/AlN/GaN HFET structures
Authors: Leach Jacob H. , Wu Mo , Ni Xianfeng , Li Xing , Özgür Ümit , Morkoç Hadis , Liberis Juozas , Šermukšnis Emilis , Matulionis Arvydas , Cheng Hailing , Kurdak Çagliyan , Moon Yong‐Tae 
Published: May 2010

AbstractInAlN/GaN heterostructures offer some benefits over existing AlGaN/GaN heterostructures for HFET device applications. In addition to having a larger bandgap than typical AlGaN compounds used in HFET devices (with Al < 30%), which leads to better confinement and subsequent larger power carrying capacity, InAlN can be grown lattice‐matched to GaN, resulting in strain‐free heterostructures. As such, lattice‐matched InAlN provides a unique system wherein the reliability of the devices may exceed that of the strained AlGaN/GaN devices as a result of being able to decouple the hot electron/hot phonon effects on the reliability from the strain related issues. In this work, we subjected lattice‐matched InAlN‐based HFETs to electrical stress and observed the corresponding degradation in maximum drain current. We found that the degradation rates are lower only for a narrow range of moderate gate biases, corresponding to low field average 2‐dimensional electron gas (2DEG) densities of 9–10 × 1012 cm−2. We propose that the degradation is attributable to the buildup of hot phonons since the degradation rates as a function of electron density generally follow the hot phonon lifetime versus electron density. This provides evidence that hot phonons have a significant role in device degradation and there exists an optimal 2DEG density to minimize hot phonon related degradation. We did not observe any correlation between the degradation rate and the gate leakage.
True green InGaN laser diodes
Authors: Lutgen Stephan , Avramescu Adrian , Lermer Teresa , Queren Desiree , Müller Jens , Bruederl Georg , Strauss Uwe 
Published: May 2010

AbstractWe present true green InGaN ridge waveguide (RWG) laser diodes (LDs) at 520 nm on c‐plane GaN substrates in pulse operation at room temperature. Defect reduction in the In‐rich quantum wells by improving growth conditions of the epitaxial layers is the key parameter to demonstrate laser operation at this wavelength. Carrier lifetime measurements in combination with electroluminescence (EL) data and simulations of competing recombination processes below laser threshold confirm that the reduction of defects in the light emitting InGaN quantum wells is essential to realize true green nitride‐based LDs with low laser threshold of 125 mA and good slope efficiency of 220 mW/A for optical output power level up to 50 mW. Investigation of the lateral far field of 520 nm RWG LDs shows a perfect beam quality. The measured vertical far field shows a substrate mode due to leakage into the transparent GaN substrate supported by waveguide simulations with an additional internal loss of less than 1 cm−1. Mounted InGaN‐based ridge LDs at 500 nm demonstrate high optical output power of 35 mW in cw operation with good wall plug efficiency of 3.5% at room temperature.
Effect of nanoscale confinement on fluorescence of MEH‐PPV/MCM‐41 composite
Authors: Telbiz German M. , Posudievsky Oleg Yu. , Dementjev Andrei , Kiskis Juris , Gulbinas Vidmantas , Valkunas Leonas 
Published: May 2010

AbstractFluorescence spectra and kinetics of poly(2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene vinylene) (MEH‐PPV)/MCM41 silica composite have been analyzed at different temperatures and compared with fluorescence properties of MEH‐PPV solutions and spin coated films. As follows from this comparison, the composite possesses significantly wider fluorescence spectra, longer fluorescence relaxation and weaker temperature dependence of its intensity. These peculiarities are explained in terms of the reduced exciton diffusion and an increased torsional disorder of polymer chains embedded in pores.
Memory performance, brain excitatory amino acid and acetylcholinesterase activity of chronically aluminum exposed mice in response to soy isoflavones treatment
Authors: Liu Yan‐qiang , Xin Tian‐rong , Liang Jing‐jing , Wang Wei‐ming , Zhang Yuan‐yuan 
Published: May 2010

AbstractMemory performance, brain excitatory amino acid and acetylcholinesterase activity of chronically aluminum (Al) exposed mice in response to soy isoflavones (SI) treatment was investigated in the study. Forty eight mice were allotted randomly into a control group, an Al exposed group (100 mg/kg Al) and an Al exposed group treated with SI (100 mg/kg Al + 60 mg/kg SI) for 60 days. Chronic Al exposure significantly impaired long memory performance in mice as assessed using a passive avoidance task test (χ2 analysis, p < 0.05). Interestingly, SI treatment markedly improved the memory performance score in the Al exposed mice. This improvement was associated with a total reversal of Al‐induced increases in acetylcholinesterase activity in the cerebral cortex and hippocampus of mice. The Al exposure also led to significant decreases in brain levels of aspartic and glutamic acids, two excitatory amino acid neurotransmitters; whereas SI treatment partially reversed the decreased aspartic and glutamic acid contents in the hippocampus. The results suggest that SI can improve long memory performance in the Al exposed mice, possibly by modulating the metabolism of brain acetylcholine and amino acid neurotransmitters. Copyright © 2010 John Wiley & Sons, Ltd.
Antitumour effects of phyllanthus emblica L.: Induction of cancer cell apoptosis and Inhibition of in vivo tumour promotion and in vitro invasion of human cancer cells
Authors: Ngamkitidechakul C. , Jaijoy K. , Hansakul P. , Soonthornchareonnon N. , Sireeratawong S. 
Published: May 2010

AbstractPhyllanthus emblica Linn. (PE) is a medicinal fruit used in many Asian traditional medicine systems for the treatment of various diseases including cancer. The present study tested the potential anticancer effects of aqueous extract of PE in four ways: (1) against cancer cell lines, (2) in vitro apoptosis, (3) mouse skin tumourigenesis and (4) in vitro invasiveness. The PE extract at 50–100 µg/mL significantly inhibited cell growth of six human cancer cell lines, A549 (lung), HepG2 (liver), HeLa (cervical), MDA‐MB‐231 (breast), SK‐OV3 (ovarian) and SW620 (colorectal). However, the extract was not toxic against MRC5 (normal lung fibroblast). Apoptosis in HeLa cells was also observed as PE extract caused DNA fragmentation and increased activity of caspase‐3/7 and caspase‐8, but not caspase‐9, and up‐regulation of the Fas protein indicating a death receptor‐mediated mechanism of apoptosis. Treatment of PE extract on mouse skin resulted in over 50% reduction of tumour numbers and volumes in animals treated with DMBA/TPA. Lastly, 25 and 50 µg/mL of PE extract inhibited invasiveness of MDA‐MB‐231 cells in the in vitro Matrigel invasion assay. These results suggest P. emblica exhibits anticancer activity against selected cancer cells, and warrants further study as a possible chemopreventive and antiinvasive agent. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of in vivo antihypertensive and in vitro vasodepressor activities of the leaf extract of syzygium guineense (willd) D.C.
Authors: Ayele Yohannes , Urga Kelbessa , Engidawork Ephrem 
Published: May 2010

AbstractThe aim of this work was to evaluate the antihypertensive activity of the hydroalcohol extract of the leaves of Syzygium guineense (Willd) D.C. (Myrtaceae) in a 1‐kidney‐1‐clip rat model and its vasorelaxant effect on isolated aorta. The extract reduced blood pressure in a dose and time dependent fashion. Following 3 days of treatment, single oral daily doses of 50, 100 and 150 mg/kg caused an overall reduction (p < 0.05) of systolic blood pressure by 6.9, 34.0 and 40.8 mmHg, respectively. The diastolic blood pressure was, however, significantly reduced (p < 0.05) by 100 mg/kg (10.3 mmHg) and 150 mg/kg (18.4 mmHg) doses only. The mean blood pressure was reduced by 5.0, 18.3 and 25.9 mmHg by the respective doses. The extract also caused a dose‐dependent relaxation of aorta precontracted with KCl at a concentration of 5–70 mg/mL, with a maximum relaxation of 56.22% achieved at 70 mg/mL concentration. The relaxation mechanism was found to be independent of the endothelium system, muscarinic receptors, histamine receptors, ATP dependent K+ channels, cyclooxygenase enzymes and cGMP/NO pathway. The findings suggest that the extract had an antihypertensive effect most likely caused by dilation of the blood vessels, a confirmation for the folkloric use of the plant. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of intraperitoneal and intracerebroventricular injection of crocin on acute corneal pain in rats
Authors: Tamaddonfard Esmaeal , Hamzeh‐Gooshchi Nasrin 
Published: May 2010

AbstractIn this study, the effects of intraperitoneal (i.p.) and intracerebroventricular (i.c.v.) injection of crocin in separate and combined treatments with i.p. injections of morphine (an opioid receptor agonist) and naloxone (an opioid receptor antagonist) were investigated on acute corneal pain in rats. Acute corneal pain was induced by local application of a drop of 5 M NaCl solution on the corneal surface. The number of eye wipes was taken as a pain response, and counted during the first 30 s. Crocin injected i.p. and i.c.v. and morphine injected i.p. significantly (p < 0.05) decreased the number of eye wipes. Morphine (i.p.)‐induced antinociception was significantly (p < 0.05) increased by the systemically and centrally injected crocin. The antinociceptive effects induced by i.p. and i.c.v. injections of crocin were not reversed by i.p. injection of naloxone. These findings indicated that both crocin and morphine attenuated hypertonic saline‐induced corneal pain. The opioid receptors may not be involved in the analgesic mechanism of crocin. Copyright © 2010 John Wiley & Sons, Ltd.
NFκB: a promising target for natural products in cancer chemoprevention
Authors: Luqman Suaib , Pezzuto John M. 
Published: May 2010

AbstractThe transcription factor nuclear factor kappa B (NFκB) is found in nearly all animal cell types. It is involved in cellular responses to stimuli such as stress, cytokines, free radicals, ultraviolet irradiation, oxidized LDL and microbial antigens, and has been shown to regulate the expression of a number of genes including bcl‐2, bcl‐xl, cIAP, suvivin, TRAF, COX‐2, MMP‐9, iNOS and cell cycle‐regulatory components. Many carcinogens, inflammatory agents and tumor promoters have been shown to activate NFκB, and resulting tumors demonstrate misregulated NFκB. Incorrect regulation of NFκB has been linked to inflammatory and autoimmune diseases, septic shock, viral infection and improper immune development. Aberrant regulation of NFκB is involved in cancer development and progression as well as in drug resistance. Inhibitors of NFκB mediate effects potentially leading to antitumor responses or greater sensitivity to the action of antitumor agents. Tools have been developed for the rapid assessment of NFκB activity, so in concert with a better understanding of NFκB activation mechanisms, many agents capable of suppressing NFκB activation have been identified. The present article focuses on the functions of NFκB, its role in human cancer and the therapeutic potential and benefit of targeting NFκB by natural products in cancer chemoprevention. Copyright © 2010 John Wiley & Sons, Ltd.
Novel natural peptides from Hyla arborea schelkownikowi skin secretion
Authors: Samgina T. Yu. , Gorshkov V.A. , Artemenko K.A. , Kovalev S.V. , Ogourtsov S.V. , Zubarev R. A , Lebedev A.T. 
Published: May 2010

AbstractHyla arborea schelkownikowi is one of the leaf frog species inhabiting the southern territories of Russia and the former USSR. This frog species is a member of the Hylidae Rafinesque, 1815 batrachians family. The present study deals with the previously uninvestigated peptidome of the Hyla arborea schelkownikowi skin secretion. Nano‐electrospray ionization Fourier transform mass spectrometry (nanoESI‐FTMS) of the skin secretion, in the intact form and after acetylation, was selected as the general method of analysis. Electron‐capture dissociation (ECD) and collision‐induced dissociation (CID) fragmentation were both employed, while de novo sequencing was performed by manual interpretation of the MS data. The suppression of the cyclization of b‐ions in the mass spectrometer by the acetylation reaction proved to be very efficient for the de novo sequencing of short peptides. Ten skin peptides were found and all of them, except for bradykinin, had not previously been reported. Six of the peptides belong to the tryptophyllins and related peptides, while three peptides are similar to the aureins. Copyright © 2010 John Wiley & Sons, Ltd.
Reconstructing bulk isotope ratios from compound‐specific isotope ratios
Authors: Morrison Douglas J. , Cooper Karen , Preston Tom 
Published: May 2010

AbstractCarbon isotope analysis by bulk elemental analysis coupled with isotope ratio mass spectrometry has been the mainstay of δ13C analyses both at natural abundance and in tracer studies. More recently, compound‐specific isotope analysis (CSIA) has become established, whereby organic constituents are separated online by gas or liquid chromatography before oxidation and analysis of CO2 for constituent δ13C. Theoretically, there should be concordance between bulk δ13C measurements and carbon‐weighted δ13C measurements of carbon‐containing constituents.To test the concordance between the bulk and CSIA, fish oil was chosen because the majority of carbon in fish oil is in the triacylglycerol form and ∼95% of this carbon is amenable to CSIA in the form of fatty acids. Bulk isotope analysis was carried out on aliquots of oil extracted from 55 fish samples and δ13C values were obtained. Free fatty acids (FFAs) were produced from the oil samples by saponification and derivatised to fatty acid methyl esters (FAMEs) for CSIA by gas chromatography/combustion/isotope ratio mass spectrometry. A known amount of an internal standard (C15:0 FAME) was added to allow analyte quantitation. This internal standard was also isotopically calibrated in both its FFA (δ13C = −34.30‰) and FAME (δ13C = −34.94‰) form. This allowed reporting of FFA δ13C from measured FAME δ13C values. The bulk δ13C was reconstructed from CSIA data based on each FFA δ13C and the relative amount of CO2 produced by each analyte.The measured bulk mean δ13C (SD) was −23.75‰ (1.57‰) compared with the reconstructed bulk mean δ13C of −23.76 (1.44‰) from CSIA and was not significantly different. Further analysis of the data by the Bland‐Altman method did not show particular bias in the data relative to the magnitude of the measurement. Good agreement between the methods was observed with the mean difference between methods (range) of 0.01‰ (−1.50 to 1.30). Copyright © 2010 John Wiley & Sons, Ltd.
Structural identification of mouse urinary metabolites of pterostilbene using liquid chromatography/tandem mass spectrometry
Authors: Shao Xi , Chen Xiaoxin , Badmaev Vladimir , Ho Chi‐Tang , Sang Shengmin 
Published: May 2010

AbstractPterostilbene, the dimethoxy derivative of resveratrol, has drawn much attention recently due to its potential beneficial health effects. The metabolic fate of pterostilbene, however, is not well understood. In the present study, we identified nine novel mouse urinary pterostilbene metabolites, pterostilbene glucuronide, pterostilbene sulfate, mono‐demethylated pterostilbene glucuronide, mono‐demethylated pterostilbene sulfate, mono‐hydroxylated pterostilbene, mono‐hydroxylated pterostilbene glucuronide, mono‐hydroxylated pterostilbene sulfate, and mono‐hydroxylated pterostilbene glucuronide sulfate, using liquid chromatography/atmospheric pressure chemical ionization and electrospray ionization tandem mass spectrometry. The structures of these metabolites were confirmed by analyzing the MSn (n = 1–3) spectra. To our knowledge, this is the first report of the identification of urinary metabolites of pterostilbene in mice. Copyright © 2010 John Wiley & Sons, Ltd.
Towards a new approach to query search engines: the Search Tree visual language
Authors: Paolino Luca , Sebillo Monica , Tortora Genoveffa , Vitiello Giuliana 
Published: May 2010

AbstractIn this paper, we describe theit Search Tree visual language. It is a novel methodology able to support users to build up complex queries to be run on given search engines. For using this visual language, neither parentheses nor precedence rules are needed, nor the specific ability to perform advanced search tasks. The language is proven to have the same expressive power as the expressions in Sum Of Product form. In order to prove the appropriateness of our proposal, we measured the usability of the proposed querying approach against the traditional Yahoo TM web search query language. Results show that, even if both the approaches fully support users in terms of efficacy, the Search Tree visual language significantly improves task efficiency, both in terms of the number of actions performed and the time requested with respect to the advanced search interface. Copyright © 2010 John Wiley & Sons, Ltd.
Web‐oriented business intelligence solution based on Associative Query Logic
Authors: Sendín‐Raña P. , Rodríguez‐Fernández E. , González‐Castaño F. J. , Costa‐Montenegro E. , Rodríguez‐Hernández P. S. , Pousada‐Carballo J. M. , Burguillo‐Rial J. C. 
Published: May 2010

AbstractIn this paper we present our experience in the development of a web‐based business intelligence tool according to the Associative Query Logic paradigm, which can represent large amounts of data in a way that allows extremely fast queries. It has been developed as an open‐source, multi‐platform software, relying on data compression techniques for the storage of large amounts of data in the main memory. The performance of our solution in terms of compression, load time and response time is close to that of the commercial tool of reference, QlikView. Moreover, we provide solutions to some open problems in QlikView published description, which may be beneficial to assist in the development of other open or proprietary tools. Copyright © 2010 John Wiley & Sons, Ltd.
Bone Discrepancy as a Powerful Indicator for early Surgery in Obstetric Brachial Plexus Palsy
Authors: Terzis Julia K. , Kokkalis Zinon T. 
Published: May 2010

Objectives One of the unfortunate sequelae in obstetric brachial plexus palsy (OBPP) is upper limb length discrepancy. However, the influence of primary nerve reconstruction remains undetermined. In this study, the resultant discrepancy in children with OBPP who underwent primary reconstruction was analyzed in relation to the severity of the lesion, the timing of surgery, and the functional outcome following surgery. Methods Fifty-four patients that met the inclusion criteria were included in this study. Preoperative and postoperative bilateral scanograms were obtained to document the effect of reinnervation on bone growth. The length of the humerus, ulna, third metacarpal, third proximal phalange, and total limb length were measured and the percentage between the affected and normal side were accessed. Correlations between all the measures of limb length and measures of active motion (i.e., three different classification systems) were performed. Results Spearman's rank correlation coefficients revealed significant correlations between limb length discrepancies and nearly all measures of active upper extremity movement. The timing of surgery and the severity of the lesion significantly influenced the resultant limb length discrepancy. Conclusions The prevention of a non-acceptable upper limb discrepancy is fundamental for both the patient and family. The extent of the resultant discrepancy appeared to be strongly related to the time between injury and surgery, degree of severity, and the outcome of surgery. Patients with better functional recoveries of the affected upper extremities showed smaller differences in limb length.
Identification and Characterization of Δ12, Δ6, and Δ5 Desaturases from the Green Microalga Parietochloris incisa
Authors: Iskandarov Umidjon , Khozin‐Goldberg Inna , Cohen Zvi 
Published: May 2010

AbstractThe freshwater microalga Parietochloris incisa accumulates, under nitrogen starvation, large amounts of triacylglycerols containing approximately 60% of the ω6 very long‐chain polyunsaturated fatty acid (VLC‐PUFA), arachidonic acid. Based on sequence homology, we isolated three cDNA sequences from P. incisa, designated PiDesD12, PiDesD6, PiDesD5. The deduced amino acid sequences of the three genes contained three conserved histidine motifs; the front‐end desaturases, PiDes6 and PiDes5, contained a fused N‐terminal cytochrome b5 domain. By functional characterization in the yeast Saccharomyces cerevisiae, we confirmed that PiDesD6, PiDesD5 cDNA encode membrane bound desaturases with Δ6, and Δ5 activity, respectively. Both PiDes6 and PiDes5 can indiscriminately desaturate both ω6 and ω3 substrates. A phylogenetic analysis showed that the three genes were homologous to the corresponding desaturases from green microalgae and lower plants that were functionally characterized. Quantitative real‐time PCR revealed the concerted expression pattern of all three genes in P. incisa cells subjected to nitrogen starvation, featuring maximum expression level on day 3 of starvation, corresponding to the sharpest increase in the share of arachidonic acid.
Successful pregnancy after intracytoplasmic sperm injection with testicular spermatozoa transported only under refrigeration
Authors: Inoue Taketo , Sugimoto Hironobu , Okubo Kazutoshi , Emi Nobuyuki , Matsushita Yukiko , Kojima Kenji , Nakamura Mitsuaki , Ono Yoshiyuki 
Published: May 2010

AbstractPurposeThis case report describes two successful pregnancies after intracytoplasmic sperm injection (ICSI) with testicular spermatozoa that were transported under refrigeration.MethodsTwo first‐time couples consulted our clinic concerned about their primary infertility. No sperm were present in the semen samples from either of the husbands and they were referred to the urology department (UD) of a neighbouring hospital. At the UD, seminiferous tubules were obtained by testicular sperm extraction. The tissue samples were put in a centrifuge tube with phosphate‐buffered saline at 6°C and placed with refrigerant in a cushioned styrofoam box that was then transported to our clinic. Immediately upon arrival at our clinic, testicular spermatozoa were extracted. On the same day, ovum pickup was performed and mature oocytes were extracted that were then inseminated by conventional ICSI. Fertilized eggs were cultured for 2 days, and then cleaved embryos were cryopreserved. In one case after 4 months and in the other case after 2 months of cryopreservation, the frozen‐thawed embryos were transferred.ResultBoth patients became pregnant and normal, healthy babies were born.ConclusionsThese results suggest that cases of obstructive azoospermia can be treated with ICSI by refrigerated transport of the seminiferous tubules, in cooperation with a UD, in a small single departmental obstetrics and gynecology clinic.