bluuebunny/crossref_metadata_2025_split huggingface dataset:
A locus on chromosome 8 controlling tumor regionality—a new type of tumor diversity in the mouse lung
Authors: Quan Lei , Hutson Alan , Demant Peter 
Published: October 2009

AbstractRegional specificity of lung tumor formation has rarely been studied in mouse or human. By using crosses of strains semi‐congenic for lung cancer susceptibility locus Sluc20, we have analyzed the genetic influences of Sluc20 and 5 other loci on tumor regionality in the mouse lung. We have mapped Sluc20 to a 27.92‐MB proximal region of chromosome 8 and found that it controls the number and load of only those tumors that surround or are directly adjacent to the bronchi or bronchioli (peribronchial tumors). These tumors lie outside the bronchial basement membrane and tend to reach a larger size than the tumors at other locations in the lung. Similar to tumors of alveolar lineage at other locations, peribronchial tumors stain with SP‐C but not CC10 antibody. The effects of Sluc20 alleles are additive because the number of peribronchial tumors in heterozygotes is intermediate. These findings show that tumor regionality in the mouse lung, which represents a novel level of lung tumor heterogeneity, is under specific genetic control. The identification of genes controlling lung tumor regionality will provide novel insights into the biology of lung tumors and potentially improve the possibilities of individualized prognosis and treatment in human lung cancer.
Expression and prognostic significance of iNOS in uveal melanoma
Authors: Johansson C. Christian , Mougiakakos Dimitrios , Trocme Eric , All‐Ericsson Charlotta , Economou Mario A. , Larsson Olle , Seregard Stefan , Kiessling Rolf 
Published: October 2009

AbstractUveal melanoma (UM) is the most common primary intraocular tumor in adults. Disease metastasis occurs in half of the patients and is uniformly fatal despite systemic therapy. Inducible nitric oxide synthase (iNOS) is associated with disease progression in various malignancies including cutaneous melanoma. In this retrospective cohort, we examined the prognostic value of iNOS in UM by performing immunohistochemistry on paraffin‐embedded sections of primary tumors (90 patients) and matched primary and metastatic hepatic tumors (19 patients) with complete histopathological and clinical data. We show that iNOS is expressed in UM (57% of the patients) and high iNOS levels significantly (p = 0.04; hazard ratio (HR) = 2.3) predict disease‐specific survival (DSS) as assessed by Kaplan‐Meier analysis and univariate Cox's proportional hazards regression model. Furthermore, high iNOS expression in the UM primary tissue was significantly associated with metastatic disease and vice versa. Expression of iNOS in hepatic metastases significantly (p = 0.02) predicted a shortened survival as assessed by Kaplan‐Meier analysis. However, iNOS did not appear to be a significant (p = 0.16; HR = 1.9) factor in the multivariate Cox's regression analysis performed together with the clinical parameters tumor diameter, tumor cell type, and tumor location in which only tumor diameter predicted DSS. In conclusion, iNOS predicts DSS in UM and may play a role in disease progression but it is not an independent prognostic factor.
Post‐partum testosterone administration does not reverse the effects of perinatal exposure to cadmium on rat offspring development
Authors: Couto‐Moraes R. , Felicio L. F. , Bernardi M. M. 
Published: October 2009

AbstractThis study investigated the effects of perinatal cadmium exposure on physical and reflexologic development of pup rats. It was examined if the immediate postpartum testosterone administration was able to reverse the toxic effects of the metal. Forty Wistar pregnant rats were divided into three groups: control and 10 and 20  mg  kg−1 per day of cadmium chloride. These dams were treated from gestational days 18 to 21, and until the 7th lactation day. Immediately after birth, half of the offspring from the experimental and control groups received 50  µL of testosterone 0.2% i.p. The maternal body weight gain, food and water consumption were measured during the treatment period. In pups, the body weight, body length, physical landmarks, reflex development and the general activity were assessed. Results showed that: only 20  mg  kg−1 cadmium induced maternal toxicity; pup body weight and body weight gain were reduced in all experimental groups; only the cadmium‐exposed offspring not treated with testosterone treatment showed a reduction in body length and body length gain; cadmium highest dose reduced the anogenital index in pups and delayed physical and reflexes development; and cadmium effects on the offspring, except in body length gain, were not reversed by testosterone. The results indicate that perinatal maternal exposure to cadmium promoted changes in the development of male rat offspring, reprogramming the pup's development. Testosterone administration was not able to reverse the cadmium effects, even on those parameters more directly related to the androgenic system as the testis descent and anogenital distance delays. Copyright © 2009 John Wiley & Sons, Ltd.
Metals in human placenta: focus on the effects of cadmium on steroid hormones and leptin
Authors: Stasenko Sandra , Bradford Elease M. , Piasek Martina , Henson Michael C. , Varnai Veda M. , Jurasović Jasna , Kušec Vesna 
Published: October 2009

AbstractCadmium and other metallic ions can act as metalloestrogens and endocrine disruptors of reproductive tissues and fetal development in mammals, including humans. The detrimental effects occur with respect to the synthesis of both steroid and polypeptide hormones in the placenta. Leptin is produced by the trophoblast and may regulate fetal organogenesis and development. In human term placentas, concentrations of toxic metals and their effects on steroidogenesis were assessed in healthy parturients (109 non‐smokers and 99 smokers) in relation to tobacco smoking. Trace elements (cadmium, lead, iron, zinc and copper) were analyzed in placentas using atomic absorption spectroscopy, and steroid hormones (progesterone and estradiol) were assayed in placental samples by an enzyme‐immunometric method. Cadmium concentrations were doubled in placentas of smokers as compared with non‐smokers, and placental lead and zinc concentrations increased significantly. Placental concentrations of iron, copper, progesterone and estradiol did not differ. In addition, human trophoblast cells were co‐cultured with 0, 5, 10 or 20  µm CdCl2 for 96  h and leptin mRNA assessed by quantitative polymerase chain reaction. Leptin mRNA declined dose‐responsively as a result of CdCl2 exposure. Collectively, the results confirm that human placental tissue offers a unique opportunity to biomonitor cadmium exposure in both the maternal and the internal fetal environments. In addition, the results strongly suggest that cadmium may cause a decline in placental leptin synthesis, as we have previously shown for placental progesterone production. This may constitute further evidence of the endocrine‐disrupting effects of cadmium, as a constituent of tobacco smoke, on reproduction in women. Copyright © 2009 John Wiley & Sons, Ltd.
In vivo imaging of hematopoietic stem cells and their microenvironment
Authors: Celso Cristina Lo , Wu Juwell W. , Lin Charles P. 
Published: October 2009

AbstractIn this review we provide a description of the basic concepts and paradigms currently constituting the foundations of adult stem cell biology, and discuss the role that live imaging techniques have in the development of the field. We focus on live imaging of hematopoietic stem cells (HSCs) as the basic biology and clinical applications of HSCs have historically been at the forefront of the stem cell field, and HSC are the first mammalian tissue stem cells to be visualized in vivo using advanced light microscopy techniques. We outline the current technical challenges that remain to be overcome before stem cells and their niche can be more fully characterized using the live imaging technology. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A compound QM/MM procedure: Comparative performance on a pyruvate formate‐lyase model system
Authors: Condic‐Jurkic Karmen , Zipse Hendrik , Smith David M. 
Published: October 2009

AbstractWe present an ONIOM(G3:MM) method as an example of a technique capable of producing chemical accuracy in the quantum mechanical (QM) treatment with a molecular mechanical description context. By applying the method to small model systems, in which we are also able to calculate the pure QM G3‐type results, it is possible to establish the reliability of the method as it applies to evaluating reaction mechanisms. By choosing small model systems that are relevant to the substrate mechanism of pyruvate formate‐lyase, we are also able to discuss the inhibitory effect of oxamate and the relevance of an alternative H‐abstraction mechanism in that context. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Multicanonical ab inito QM/MM molecular dynamics simulation of a peptide in an aqueous environment
Authors: Jono Ryota , Watanabe Yuusuke , Shimizu Kentaro , Terada Tohru 
Published: October 2009

AbstractWe developed a multicanonical ab initio QM/MM molecular dynamics simulation method to enhance conformational sampling of biomolecules in an aqueous environment. We applied this method to an alanine dipeptide immersed in a sphere of explicit water molecules. The peptide and the water molecules were treated by the QM method at the HF/3‐21G level and by the MM method, respectively. The van der Waals interactions between the peptide and the water molecules were calculated at the MM level, while the electrostatic interaction terms between them were incorporated into the QM Hamiltonian to account for the effect of the solvent on the electronic structure of the peptide. The simulation was performed for 1 ns, and a free‐energy map was calculated with respect to the peptide conformation. All the conformations (C5, PII, C7eq, and αR) that have been experimentally suggested to exist in solution formed basins on the free‐energy surface. Analysis of the water distribution revealed that the αR conformation was stabilized by the interaction between the large electric dipole moments of this peptide conformation and the water electric dipole moments, whereas the PII conformation was stabilized by the formation of characteristic hydrogen bonds with the water molecules. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Temperature dependence of structure and dynamics of the hydrated Ca2+ ion according to ab initio quantum mechanical charge field and classical molecular dynamics
Authors: Lim Len Herald V. , Pribil Andreas B. , Ellmerer Andreas E. , Randolf Bernhard R. , Rode Bernd M. 
Published: October 2009

AbstractSimulations using ab initio quantum mechanical charge field molecular dynamics (QMCF MD) and classical molecular dynamics using two‐body and three‐body potentials were performed to investigate the hydration of the Ca2+ ion at different temperatures. Results from the simulations demonstrate significant effects of temperature on solution dynamics and the corresponding composition and structure of hydrated Ca2+. Substantial increase in ligand exchange events was observed in going from 273.15 K to 368.15 K, resulting in a redistribution of coordination numbers to lower values. The effect of temperature is also visible in a red‐shift of the ion‐oxygen stretching frequencies, reflecting weakened ligand binding. Even the moderate increase from ambient to body temperature leads to significant changes in the properties of Ca2+ in aqueous environment. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Vibrational spectroscopic studies and computational study of methyl(2‐methyl‐4,6–dinitrophenylsulfanyl)ethanoate
Authors: Panicker C. Yohannan , Raj Asha , Varghese Hema Tresa , Raju K. , Sheena Mary Y. 
Published: October 2009

AbstractFT‐IR and FT‐Raman spectra of methyl(2‐methyl‐4,6–dinitrophenylsulfanyl)ethanoate (MDIE) were recorded and analyzed. Surface‐enhanced Raman scattering (SERS) spectra were recorded in silver colloid and silver electrode. The vibrational wavenumbers were computed using HF/6‐31G* and B3LYP/6‐31G* basis. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands obtained in infrared and Raman spectroscopies as well as in SERS of the studied molecule. The first hyperpolarizability and infrared intensities are reported. The geometrical parameters of the title compound are in agreement with the reported similar derivatives. The presence of new bands at 1045 and 948 cm−1 in the SERS spectrum in silver electrode is related to the change in orientation of the molecule with respect to the metal surface. In silver colloid SERS spectrum, the methyl group attached to the methoxy carbonyl group is close to the metal surface, whereas on silver electrode the methyl group attached to the phenyl ring is close to the metal surface. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and properties of polystyrene‐g‐mSiO2 filled polypropylene nanocomposites
Authors: Cai Aiyun , Zhang Shilian , Zhu Aiping , Dai Sheng 
Published: October 2009

AbstractHydrophobically modified nanosilica was prepared from tetraethoxysilane (TEOS) and γ‐methacryloxypropyltrimethoxysilane (MPS) by a two step sol‐gel process. The polystyrene‐grafted‐modified nanosilica (PS‐g‐mSiO2) hybrid particles were prepared by grafting polystyrene onto the resulting hydrophobically modified nanosilica by dispersion polymerization. The hybrid nanoparticles were subsequently used as the filler to fabricate polypropyrene (PP) nanocomposites. The crystallization kinetics, crystal morphology and crystallization phase component of PS‐g‐mSiO2/PP nanocomposite were studied using a differential scanning calorimeter (DSC), polarizing optical microscopy (POM) and X‐ray diffraction (XRD). Crystallization half life (t1/2) decreased, while the Arami exponent (n) of PS‐g‐mSiO2/PP nanocomposite increased compared with that of virgin PP. A rheological study allowed the unambiguous characterization of the dispersibility of nanosilicas in PS‐g‐mSiO2/PP nanocomposite. The storage modulus, melt viscosity and the elongation to break of the PS‐g‐mSiO2/PP nanocomposite were found to be strongly dependent on the grafting of PS on nanosilicas. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Issues in monitoring medication effects in the classroom
Authors: Anderson Laura , Walcott Christy M. , Reck Sarah G. , Landau Steven 
Published: October 2009

AbstractThe task of medication monitoring in the schools has increased for school psychologists, yet there is little research specific to pediatric psychoactive medication. The current article reviews issues pertinent to school‐based medication monitoring. Feasibility, acceptability, and perception of effectiveness are reviewed as fundamental considerations before implementing a medication‐monitoring plan in the schools. The importance of individualization, ecological implementation, and development of socially valid objectives is stressed along with the need for additional research, tools, and measures in this area. Practical considerations for school psychologists include discussion of parental consent and confidentiality, multilevel assessment and monitoring, data recording, and determining clinical significance. © 2009 Wiley Periodicals, Inc.
Prescription drug abuse
Authors: Hamilton Gloria J. 
Published: October 2009

AbstractThis article presents current statistics on nonmedical use of both categories of prescription medications by high school and college students. The incidence of nonmedical use of prescription medications continues to increase among high school and college students. Two categories of drugs that are commonly used for reasons other than those for which the drugs are prescribed are those used for pain and those prescribed for Attention‐Deficit/Hyperactivity Disorder. Demographic and behavioral characteristics of students who are most likely to engage in intentional abuse of stimulants and pain medications as well as stated motivations for use are presented. © 2009 Wiley Periodicals, Inc.
Measurements of current‐voltage characteristics of separate single GaAs nanowhiskers
Authors: Dunaevskiy Mikhail , Dementyev Petr , Egorov Vyacheslav , Polyakov Nikolay , Samsonenko Yuri , Cirlin George , Titkov Alexander 
Published: October 2009

AbstractIn this work a method is proposed for measurements of current‐voltage (I‐V) characteristics for individual semiconductor nanowhiskers (NWs) standing on the growth surface. It is shown that conductive probe of atomic force microscope (AFM) can be placed at the top of nanowhiskers with a great precision and used as a stable local electrode. For that, a fixation of NWs is necessary to avoid lateral bending of NWs under pressure of AFM probe. In the present work we have studied current‐voltage characteristics of NWs with radial heterostructure GaAs/AlGaAs grown under Au droplets on GaAs substrate. For fixation, NWs were partially overgrown with GaAs layer. The current‐voltage characteristics measurements on the fixed NWs permitted to investigate the Si‐doping of GaAlAs/GaAs NWs. They were found to be Schottky barrier p‐type curves, what shows that Si‐atoms incorporate into GaAs NWs with a formation of acceptor centres contrary to the case of bulk GaAs. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Advanced materials for light emitting diodes: noise characterisation
Authors: Palenskis Vilius , Matukas Jonas , Pralgauskaitė Sandra , Šaulys Bronius , Laučius Juozas 
Published: October 2009

AbstractComprehensive investigation of optical and electrical characteristics of nitride‐based (InGaN) light emitting diodes (LEDs), and comparison of the results with those for phosphide‐based (AlInGaP) are presented. The main attention was pointed to investigation of the optical and electrical fluctuations and their correlation. It is shown that correlation factor between optical and electrical fluctuations is very sensitive to device defectiveness. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Specific response of ultra‐thin metal oxide films to gas
Authors: Šetkus Arūnas , Bukauskas Virginijus , Mironas Audružis , Senulienė Daiva , Strazdienė Viktorija 
Published: October 2009

AbstractTin and indium oxide ultra‐thin film (UTF) based structures are investigated in the present study. Current‐voltage characteristics (IVC) are measured in the samples by a contact current mode of scanning probe microscopy (SPM). It is proved that the IVC splits into two paths corresponding to increase and decrease of applied voltage, respectively. Detailed investigations of the electrical properties of the ultra‐thin metal oxide (MOX) films revealed a dependence of the IVC on the structure of the films, on initial conductivity and on the surrounding gases. It was proved that the IVC is typically split only if the maximum dc‐voltage exceeds some critical magnitude that is not the same in indium and tin oxide based films. The properties of the ultra‐thin MOX structures are explained in terms of distribution of stoichiometry in MOX based nanometer systems. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low‐temperature MBE‐grown GaBiAs layers for terahertz optoelectronic applications
Authors: Pačebutas Vaidas , Bertulis Klemensas , Bičiūnas Andrius , Krotkus Arūnas 
Published: October 2009

AbstractGallium bismide arsenide epitaxial layers were grown by molecular‐beam‐epitaxy at low substrate temperatures and investigated for their suitability in terahertz optoelectronic applications. Optical pump‐terahertz probe measurements on these layers have shown that carrier dynamics can be described using two characteristic times. The faster decay component has characteristic times shorter than 1 ps, whereas the slower component decays in several tens of picoseconds. Fitting the electron lifetimes dependence on optical excitation level the electron trapping cross‐section and trap density were determined. The possible mechanism of carrier recombination was discussed. The photoconductive terahertz emitters and detectors made from GaBiAs layers have been manufactured and used in time‐domain spectroscopy system with a signal bandwidth larger than 4.5 THz. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Merging percolation on Zd and classical random graphs: Phase transition
Authors: Turova Tatyana S. , Vallier Thomas 
Published: October 2009

AbstractWe study a random graph model which is a superposition of bond percolation on Zd with parameter p, and a classical random graph G(n,c/n). We show that this model, being a homogeneous random graph, has a natural relation to the so‐called “rank 1 case” of inhomogeneous random graphs. This allows us to use the newly developed theory of inhomogeneous random graphs to describe the phase diagram on the set of parameters c ≥ 0 and 0 ≤ p < pc, where pc = pc(d) is the critical probability for the bond percolation on Zd. The phase transition is of second order as in the classical random graph. We find the scaled size of the largest connected component in the supercritical regime. We also provide a sharp upper bound for the largest connected component in the subcritical regime. The latter is a new result for inhomogeneous random graphs with unbounded kernels. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Effects of annealing temperature on electrical and structural properties of Mo/n‐InP (100) Schottky contacts
Authors: Janardhanam V. , Ashok Kumar A. , Rajagopal Reddy V. , Narasimha Reddy P. 
Published: October 2009

AbstractThe electrical, structural and surface morphological properties of Mo/n‐InP Schottky diodes have been investigated as a function of annealing temperature using current–voltage (I–V), capacitance–voltage (C–V), Secondary Ion Mass Spectroscopy (SIMS), X‐ray diffraction (XRD) and atomic force microscopy (AFM) measurements. The obtained Schottky barrier heights from I–V and C–V measurements for as‐deposited Mo/n‐InP are 0.45 eV and 0.61 eV respectively. Upon annealing at 300 °C in nitrogen atmosphere for 1 min, the barrier height values increased to 0.47 eV (I–V) and 0.68 eV (C–V). When the samples are annealed at temperatures 400 and 500 °C, the barrier height values decrease to 0.46 eV (I–V), 0.44 eV (I–V) and 0.65 eV (C–V), 0.64 eV (C–V). The SIMS and XRD results showed the formation of phosphide phases at the Mo/n‐InP interface, which may be the reason for the decrease in the barrier height for samples annealed at 500 °C. The AFM measurements showed that the surface morphology of Mo contacts on n‐InP is smooth with a root mean square value of 12.7 nm even after annealing at 500 °C. Copyright © 2009 John Wiley & Sons, Ltd.
Communication protocols for vehicularad hocnetworks
Authors: Casteigts Arnaud , Nayak Amiya , Stojmenovic Ivan 
Published: October 2009

AbstractVehicular networks are envisioned for large scale deployment, and standardization bodies, car manufacturers, and academic researchers are solving a variety of related challenges. After a brief description of intelligent transportation system (ITS) architectures and the main already‐established low‐level standards, this tutorial elaborates on four particular aspects of vehicular networks, which are (i) the potential for a large set of innovative applications, (ii) a review of the main modeling approaches used for both roads and traffic, and finally two important communication primitives, that are (iii) data disseminationviabroadcasting/geocasting, and (iv) routing in both highway and urban environments. A particular emphasis is on recent protocols that realistically consider the inherently complex nature of vehicular mobility, such as intermittent connectivity, speed variability, and the impact of intersections. Copyright © 2009 John Wiley & Sons, Ltd.