bluuebunny/crossref_metadata_2025_split huggingface dataset:
Purification and partial characterization of xyloglucan‐hydrolyzing enzymes from watermelon placental tissue
Authors: Karakurt Yasar , Huber Donald J 
Published: January 2009

AbstractBACKGROUND: Watermelon (Citrullus lanatus (Thunb.) Matsum & Nakai) fruit matrix glycans are comprised largely of xyloglucans (XGs). As in other fruits, these polymers show significant molecular mass downshifts during ripening. In the present study, we describe the purification and characteristics of a number of xyloglucanases (XGases) from the placental tissue of ripe watermelon. XGases were extracted from watermelon fruit placental tissue and purified by sequential ion‐exchange, gel‐permeation and concanavalin A chromatography.RESULTS: Five XGases (P1S2, P2S2, P3S1, P3S2, P3S3) were recovered with molecular masses ranging from 30.5 to 77.5 kDa on SDS‐PAGE. All XGases showed maximum activity at pH 5–5.5 and 35–40 °C against tamarind seed XG and were also active against XG‐rich matrix glycans from watermelon fruit. The enzymes were strongly inhibited by mercury and hydrolyzed XG without generation of oligomers or monomers. P3S3 had the highest activity against XG. The purified enzymes were active toward carboxymethylcellulose, indicating that they were not XG specific.CONCLUSION: The pattern of molecular mass downshifts during XG hydrolysis by the purified XGases and the absence of monomeric and oligomeric products are consistent with endo‐type catalysis for the XGases and with a role for these enzymes in the degradation of cell wall XG during ethylene‐induced watersoaking of watermelon fruit placental tissues. Copyright © 2009 Society of Chemical Industry
Timing of referral for prenatal genetic counselling
Authors: Schmid Maximilian , Drahonsky Regina , Fast‐Hirsch Christa , Baumühlner Konstantin , Husslein Peter , Blaicher Wibke 
Published: January 2009

AbstractObjectiveTo evaluate the timing of referrals for prenatal genetic counselling.MethodThe data of 406 consecutive patients referred because of a family history of genetic disease or a suspected risk factor for genetic disease other than an unfavourable first trimester screening outcome were retrospectively analysed.ResultsIn 37.2% (151/406) of included patients, a pregnancy was already ongoing. The mean gestational age at first contact was 13.6 weeks (SD 5.5 weeks). The main counselling issues were previous pregnancy with abortive outcome (ICD O00‐O08) 23.9% (97/406), chromosomal abnormalities (ICD Q90‐Q99) 16.7% (68/406) and metabolic disorders (ICD E70‐E90) 9.9% (40/406). As a result of prenatal genetic counselling, invasive prenatal diagnostic procedures were performed in 11.3% (46/406) of all patients.ConclusionPatients are often referred to prenatal genetic counselling when prenatal diagnosis of a familial genetic condition is no longer feasible, preventive measures are limited and alternative reproductive options have become impossible. Healthcare providers are challenged to improve services so prenatal genetic counselling can take place before conception. Copyright © 2009 John Wiley & Sons, Ltd.
Exciton fine structures and energy transfer in single InGaAs quantum‐dot molecules
Authors: Lin Hsuan , Wang Sheng‐Yun , Lin Chia‐Hsien , Chang Wen‐Hao , Cheng Shun‐Jen , Lee Ming‐Chih , Chen Wen‐Yen , Hsu Tzu‐Min , Hsieh Tung‐Po , Chyi Jen‐Inn 
Published: January 2009

AbstractWe present a spectroscopic study of single quantum‐dot molecules (QDMs) formed by two closely stacked In0.5Ga0.5As/GaAs layers. It was found that the interdot coupling and directional energy transfer between the two adjacent dots can be controlled by temperature tuning. Direct and indirect excitons, as well as charged excitons in single QDMs were classified and identified by excitation‐power dependent, excitation‐energy dependent and polarization‐resolved micro‐photoluminescence measurements. With the increasing temperature, the direct‐exciton intensity decreases while the indirect‐exciton intensity increases. A rate equation model considering phonon mediated processes has been developed. The directional energy transfer in QDMs is explained in terms of the phonon‐assisted tunnelling of hole between the two adjacent dots. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Observation of enhanced luminescence emitted from InAs quantum dots with direct contact to superconducting niobium stripe
Authors: Idutsu Yasuhiro , Takada Makoto , Hayashi Yujiro , Akazaki Tatsushi , Kumano Hidekazu , Suemune Ikuo 
Published: January 2009

AbstractObservation of drastically enhanced luminescence emitted from InAs quantum dots (QDs) which were in direct contact to superconducting Niobium (Nb) is reported. Although the PL intensity was essentially temperature independent without Nb stripe, drastic temperature dependence was observed with the presence of the Nb stripe. PL intensity was substantially increased below the Nb superconducting critical temperature (Tc). About 3‐times enhancement was observed below Tc. This phenomenon is attributed to the Cooper pairs penetrated from the superconducting Nb stripe to adjacent InAs QDs by the proximity effect. This is the first experimental demonstration that the Cooper pairs enhance radiative recombination through QDs. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polarity control and preparation of AlN nano‐islands by hydride vapor phase epitaxy
Authors: Nagashima Toru , Hironaka Keiichiro , Ishizuki Masanari , Kumagai Yoshinao , Koukitu Akinori , Takada Kazuya 
Published: January 2009

AbstractInitial growth condition of AlN on sapphire substrate by HVPE was investigated. It was found that polarity of AlN was significantly affected by temperature even under the condition of AlCl3 pre‐flow and that polarity was drastically changed from N‐polarity to Al‐polarity with increasing temperature around 1000 °C. Polarity of AlN was easily controlled by growth temperature. By utilizing these findings and etching technique by alkaline solution, AlN nano‐islands were successfully obtained on sapphire substrates. AlN nano‐islands had mixture of trapezoid and column structure with 100 nm or less in diameter. Also it had epitaxial relation to sapphire substrates. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High breakdown voltage in AlGaN/GaN/AlGaN double heterostructures grown on 4 inch Si substrates
Authors: Visalli Domenica , Van Hove Marleen , Derluyn Joff , Cheng Kai , Degroote Stefan , Leys Maarten , Germain Marianne , Borghs Gustaaf 
Published: January 2009

AbstractWe report high breakdown combined with low on‐resistance results on AlGaN/GaN/AlGaN double heterostructure devices (DHFET) grown on 4 inch Silicon substrates. On two fingers devices with gate‐drain distance (LGD) of 8 μm we measured a breakdown voltage (VBD) of 650 V and an on‐resistance (Ron) of 7.2 Ω·mm. We also demonstrated that increasing the buffer thickness and etching deep into the AlGaN buffer layer improve both buffer and device breakdown. Moreover, we have also achieved a high breakdown voltage (580 V) for smaller LGD (5 μm) combined with the lowest reported on‐resistance (6 Ω·mm) for this voltage range. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical and microstructural properties of semi‐polar (11‐22) InGaN/GaN quantum well structures
Authors: Hylton Nicholas P. , Dawson Philip , Johnston Carol F. , Kappers Menno J. , Hollander Jonathan L. , McAleese Clifford , Humphreys Colin J. 
Published: January 2009

AbstractIn this paper we report on a comparison of the optical properties of a series of semi‐polar (11‐22) InGaN/GaN multiple quantum well structures with those of a series of polar (0001) control samples. In the semi‐polar structures we observe blue‐shifts of the quantum well emission, increases of the radiative recombination rates and sharpening of the quantum well excitation spectra; all these changes are compatible with a decrease in the magnitude of the electric field strength with respect to the control samples. However the reduction in the electric field strength does not translate into an improvement in the photoluminescence internal quantum efficiency at room temperature. This failure we attribute to an increased density of non‐radiative recombination centres, arising from the larger dislocation density in the (11‐22) samples. Using TEM and STEM‐HAADF measurements we have also observed gross well width fluctuations in the (11‐22) samples which result in broadening of the photoluminescence spectra. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of the role of current in the degradation of InGaN‐based laser diodes
Authors: Meneghini Matteo , Trivellin Nicola , Meneghesso Gaudenzio , Trevisanello Lorenzo , Zanoni Enrico , Orita Kenji , Yuri Masaaki , Ueda Daisuke 
Published: January 2009

AbstractThis paper presents an analysis of the role of current in the long‐term degradation of InGaN‐based laser diodes (LDs). The analysis has been carried out by means of a wide set of stress tests under different driving conditions. During stress, the optical and electrical characteristics of the samples have been continuously monitored, with the aim of determining the physical mechanisms responsible for degradation and the dependence of the degradation rate on the driving conditions. The results reported in this paper demonstrate that: (i) constant current stress determines the increase of the threshold current of the devices, that is well related to the decrease of the sub‐threshold emission; (ii) stress induces the increase of the reverse current of the devices, but does not affect their forward‐bias characteristics; (iii) degradation rate has an almost linear dependence on stress current level; (iv) degradation takes place also below lasing threshold and for very low stress current levels, i.e. with very limited optical field levels. The results described in this paper indicate that the degradation kinetics are mostly determined by the stress current level used during operation: optical field and temperature are thought to play only a minor role in determining the degradation rate. Furthermore, the strong correlation between the threshold current increase and the sub‐threshold emission decrease suggests that degradation can be ascribed to the increase of the non‐radiative recombination rate in the active region of the devices. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Room temperature intraband Raman emission and ultrafast carrier relaxation in GaN/AlN quantum dots
Authors: Nevou L. , Mangeney J. , Tchernycheva M. , Julien F. H. , Guillot F. , Monroy E. , Sarigianni‐dou E. 
Published: January 2009

AbstractWe report on the intraband emission at room‐temperature from GaN/AlN quantum dots grown by plasma‐assisted molecular beam epitaxy as well as on the measurements of GaN quantum dot intraband relaxation using femtosecond spectroscopy. The quantum dots exhibit s‐pz intraband absorption peaked at 1.55 μm. The pz‐s intraband luminescence at λ = 1.48 μm is observed under optical excitation at λ = 1.34 μm. The population of the pz state arises from Raman scattering by GaN A1 longitudinal optical phonons. Based on the emission spectral shape, we estimate that the homogeneous linewidth of the s‐pz intraband transition is less than 4 meV.The carrier lifetime of the pz state (T1) is measured by femtosecond pump‐probe spectroscopy. T1 = 165 fs while the thermalization of electrons in the ground state proceeds in 1.5 ps. The saturation intensity of the s‐pz intraband absorption is estimated to be in the 15 to 137 MW/cm2 range taking into account the uncertainty on the pump beam waist. These results demonstrate the promising capabilities of GaN/AlN QDs for application to telecom intraband lasers as well as multi‐Tbit/s all‐optical switching devices. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High aspect ratio, self‐ordered iron oxide nanopores formed by anodization of Fe in ethylene glycol/NH4F electrolytes
Authors: Albu Sergiu P. , Ghicov Andrei , Schmuki Patrik 
Published: January 2009

AbstractIn the present work we show that highly self‐ordered iron oxide nanopores can be anodically grown to high aspect ratios, in optimized fluoride‐containing ethylene glycol electrolytes. The as‐formed layers are amorphous and contain a significant amount of fluorides. By annealing the layers can be crystallized and the fluorides can be removed. At elevated electrolyte temperatures the nanoporous system shows a transition to a nanotubular structure. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On some stationary mathematical models for Tornados and other funnel‐shaped rotating liquid and gas media
Authors: Khomasuridze N. 
Published: January 2009

AbstractBased on Navier‐Stokes stationary equations a mathematical model is constructed for liquid and gas media with funnel‐shaped rotation observed in atmospheric and sea tornados. Both compressible and incompressible media are considered. The differential equations corresponding to the mathematical model are integrated in elementary functions and the solutions are represented by seven rotationally symmetrical orthogonal curvilinear coordinates applicable to different shapes of funnels.
Reliability computation with local polynomial chaos approximations
Authors: Proppe C. 
Published: January 2009

AbstractReliability estimation for structural mechanics problems involving random fields is discussed. While in most of the literature on stochastic finite element methods to date global approximations with Hermite polynomials are considered, the benefits of local approximations are investigated in this paper. Local polynomial approximations in the vicinity of the point of most probable failure are introduced. An adaptive algorithm is proposed, that allows for efficient and accurate computations of failure probabilities.
Asymptotic structure incorporating double and triple decks
Authors: El‐Mistikawy T.M.A. 
Published: January 2009

AbstractThe flow along a flat plate of finite length develops – near the trailing edge – into a double deck structure when it is a jet layer with quiescent outer flow and into a triple deck structure when it is a boundary layer with streaming outer flow. It is shown here that the transfer from one structure to another is singular; requiring matching of two main decks. The double deck structure is, in essence, a triple deck structure with collapsing upper deck.
A generalization of the Helmholtz conditions for the existence of a first‐order Lagrangian using nonholonomic velocities
Authors: Jungnickel U. , Kielau G. , Maißer P. , Müller A. 
Published: January 2009

AbstractThe paper presents a generalization of the Helmholtz conditions for the existence of a first‐order kinetic potential (Lagrangian) in that cases where the motion equations of mechanical, electrical, or electromechanical systems are given in terms of nonholonomic velocities. It is assumed that the transformation between holonomic and nonholonomic velocities is known. It is shown how the generalized Helmholtz conditions for the simultaneous existence of a first‐order Lagrangian and a first‐order dissipation function follow from the generalized Helmholtz conditions for systems with holonomic velocities. Moreover, the classical Helmholtz conditions in case of nondissipative systems can be directly generalized to motion equations which include nonholonomic velocities. In both cases the Boltzmann‐Hamel equations are used. The approaches are demonstrated by two examples: a heavy gyroscope and a 3‐dimensional rotating electrical machine.
Hydrogen Supply Options and Issues
Authors: Kuberka Kathleen A. , Weise Mark K. , Messina Celeste A. 
Published: January 2009

AbstractMethods of hydrogen gas production for hydrogenation are discussed: steam reforming of natural gas, electrolysis, by‐product clean‐up by PSA (pressure swing absorption) or scrubbing, and others. Hydrogen can be obtained from a customer‐owned hydrogen plant or as a merchant product supplied by an industrial gas supplier. The merchant product can be delivered in trailers as gas, liquid‐high (up to 2,200 psig), low pressure (up to 130 psig), or supplied over the fence from a pipeline or hydrogen generating plant. Several factors must be considered in selecting an optimum supply, including availability and cost of capital and of operating labor, use patterns, average demand, instantaneous demand, use pressure, growth projections, and purity requirements. Recent field test data have shown that increased hydrogen purity can improve the hydrogenation processes.
Action of Tocopherol‐Type Compounds in Directing Reactions Forming Flavor Compounds in Autoxidizing Fish Oils
Authors: Karahadian C. , Lindsay R. C. 
Published: January 2009

AbstractMenhaden and cod liver oils without additives or containing either α‐tocopherol (670 ppm) or Trolox C (1000 ppm) with or without copper (II) cations (20 ppm) were oxidized under air at 65‡C, and their headspace volatiles were quantitatively measured by capillary gas chromatography. Samples prepared without additives contained very little l,5‐octadien‐3‐one. Fish oils with Trolox C had distinct metallic, vinyl‐ketone aromas, while those with a‐tocopherol exhibited extremely fishy, cod liver‐like aromas. High levels of 1,5‐octadien‐3‐one and 1,5‐octadien‐3‐ol and moderate levels of 2,4,7‐decatrienals were found in samples with Trolox C, while moderate levels of the 8‐carbon compounds and high levels of the 2,4,7‐decatrienals were present in the α‐tocopherol samples. Copper (II) greatly accelerated the overall rate of oxidation in samples, and in the presence of Trolox C it induced the formation of very high levels of 1,5‐octadien‐3‐ol.
Synthesis of substituted fatty oxathiolanes and thioethers from an allylic oxo fatty acid ester
Authors: Afaque S. , Ansari M. H. , Ahmad M. S. , Siddiqui M. S. 
Published: January 2009

AbstractSubstituted oxathiolane and thioether derivatives have been synthesized from an allylic oxo fatty acid ester. The reaction of methyl 4‐oxo‐trans‐2‐octadecenoate with 3‐mercaptopropan‐1,2‐diol (1‐thioglycerol) affords methyl 4‐(3′‐hydroxymethyl‐1′,4′‐oxathiolane)‐2(3)‐(O‐mercaptopropan‐1″,2″‐diol)‐octadecanoate (II), methyl 4‐oxo‐2(3)‐(O‐mercaptopropan‐1′,2′‐diol)‐octadecanoate (III), methyl 4‐(3′‐hydroxy‐l′,5′‐oxathiane)‐2 (3)‐(S‐mercaptopropan‐1″,2″‐diol)‐octadecanoate (IV), methyl 4‐oxo‐2(3)‐(S‐mercaptopropan‐1′, 2′diol)‐octadecanoate (V) and methyl 4‐(3′‐hydroxymethyl‐1′, 4′‐oxathiolane)‐2(3)‐(S‐mercaptopropan‐1″, 2″‐diol)‐octadecanoate (VI). Structures of the individual reaction products have been established on the basis of spectral data and microanalyses.
Study on the Electric Conductivity of Ag-Doped DNA in Transverse Direction
Authors: Ban Ge , Dong Ruixin , Li Ke , Han Hongwen , Yan Xunling 
Published: January 2009

Abstract
In this article, we reported a novel experiment results on Ag-doped DNA conductor in transverse direction.I–V characteristics were measured and the relative conductances were calculated for different silver ions concentrations. With the increase of the concentration of silver ions, the conductive ability of DNA risen rapidly, the relative conductance of DNA enhanced about three magnitudes and reached a stable value when Ag+concentration was up to 0.005 mM. In addition, Raman spectra were carried out to analyse and confirm conduction mechanism.
Ultrasonic surgical aspiration for vaginal intraepithelial neoplasia
Authors: Matsuo Koji , Chi Dennis S. , Walker LaTashia D. , Rosenshein Neil B. , Im Dwight D. 
Published: January 2009

AbstractObjectiveTo determine the safety and efficacy of ultrasonic surgical aspiration (USA) in the treatment of vaginal intraepithelial neoplasia (VAIN).MethodsUsing the ICD code for VAIN, all patients who underwent USA were evaluated. Patient demographics, clinicopathologic data, and follow‐up outcomes were abstracted from the medical records.ResultsNinety‐two patients underwent USA for VAIN. No surgical complications or postoperative scarring were recorded, and all patients were followed without further therapy after the procedure. Pathologic evaluation of the degree of VAIN in the aspirate obtained at the time of USA correlated with the preoperative biopsy results in all cases. With a median follow‐up period of 4.5 years, the overall recurrence rate was 19.6%. The recurrence rate for high grade VAIN was significantly greater than that for low grade VAIN (32.3% vs 13.1%, P = 0.044).ConclusionUltrasonic surgical aspiration is a safe and effective surgical option for VAIN, providing a histologic sample with minimal invasiveness.
Prevalence of HPV infection by cervical cytologic status in Brazil
Authors: Fernandes José Veríssimo , de Vasconcellos Meissner Rosely , de Carvalho Maria Goretti Freire , de Medeiros Fernandes Thales Allyrio Araújo , de Azevedo Paulo Roberto Medeiros , Villa Luisa Lina 
Published: January 2009

AbstractObjectivesTo assess the prevalence of human papillomavirus (HPV) infection according to cervical cytologic status in northeastern Brazil; identify other risk factors for low‐ and high‐grade squamous intraepithelial lesions (LSILs and HSILs); and identify the most prevalent HPV genotypes associated with the lesions.MethodTwo cervical smears were collected from 250 women referred for cancer screening, one for cytologic examination and the other to test for the presence of HPV by PCR with genotyping by dot blot hybridization.ResultThere were 110 healthy cervices, 82 LSILs, and 58 HSILs. The overall HPV prevalence was 48%, with higher rates for HSILs, and HPV‐16 was the most prevalent type. Age, multiple sexual partners, type of HPV present, smoking, and early onset of sexual activity were risk factors for cervical lesions.ConclusionAge, multiple sexual partners, and infection with HPV‐16 increased the risk of having LSILs or HSILs. Early onset of sexual activity and smoking only increased the risk of having HSILs.
The Revival of Equitable Estates in the Seventeenth Century: An Explanation by Lord Nottingham
Authors: Yale D. E. C. 
Published: January 2009

The purpose of this article is to give an explanation reported by Lord Nottingham about three-quarters of the way through the seventeenth century of the legal reasons justifying the resurrection of equitable estates by way of trusts after the Statute of Uses in 1535 had gone a long distance towards extirpating equitable estates in land. This explanation turns to a large degree on a restrictive interpretation of the first section of the Act, which is as follows—“That where any person or persons…at any time hereafter shall…be seised, of and in any…hereditaments, to the use confidence or trust of any other person or persons or of any body politic, by…any…means whatsoever,…in every such case all and every such person or persons and bodies politic that…shall have any such use confidence or trust…shall…be…deemed and adjudged in lawful estate seisin and possession of and in the same…hereditaments,…to all intents constructions and purposes in the law, of and in such like estates as they had or shall have in use trust or confidence of or in the same.”
Liability in Roman Law for Damage caused by Animals
Authors: Ashton-Cross D. I. C. 
Published: January 2009

Classification of AnimalsIn Roman law all animals are either wild or domestic.(i) Wild: this category includes particularly those of an innate or natural feritas, and generally all animals not normally owned. Wild animals may, however, be owned and, as will be seen later, the owner may be under legal liability in respect of any damage done by them.(ii) Domestic: these are normally owned. As a species they do not show feritas, though individually they may. Those which do show feritas are therefore regarded as acting contra naturam (of the species). So a horse which is a kicker, or a bull which gores, both of vicious disposition, are nevertheless governed by the rules relating to domestic animals; and a fortiori the domestic animal which has temporary lapses into feritas, e.g., the mare which is touchy, does not cease to be a domestic animal in law.