bluuebunny/crossref_metadata_2025_split huggingface dataset:
SWAT‐simulated hydrological impact of land‐use change in the Zanjanrood basin, Northwest Iran
Authors: Ghaffari Golaleh , Keesstra Saskia , Ghodousi Jamal , Ahmadi Hassan 
Published: December 2009

AbstractUnderstanding the impacts of land‐use changes on hydrology at the watershed scale can facilitate development of sustainable water resource strategies. This paper investigates the hydrological effects of land‐use change in Zanjanrood basin, Iran. The water balance was simulated using the Soil and Water Assessment Tool (AVSWAT2000). Model calibration and uncertainty analysis were performed with sequential uncertainty fitting (SUFI‐2). Simulation results from January 1998 to December 2002 were used for parameter calibration, and then the model was validated for the period of January 2003 to December 2004. The predicted monthly streamflow matched the observed values: during calibration the correlation coefficient was 0·86 and the Nash–Sutcliffe coefficient 0·79, compared with 0·80 and 0·79, respectively, during validation. The model was used to simulate the main components of the hydrological cycle, in order to study the effects of land‐use changes in 1967, 1994 and 2007. The study reveals that during 1967 a 34·5% decrease of grassland with concurrent increases of shrubland (13·9%), rain‐fed agriculture (12·1%), bare ground (5·5%) irrigated agriculture (2·2%), and urban area (0·7%) led to a 33% increase in the amount of surface runoff and a 22% decrease in the groundwater recharge. Furthermore, the area of sub‐basins that was influenced by high runoff (14–28 mm) increased. The results indicate that the hydrological response to overgrazing and the replacing of rangelands (grassland and shrubland) with rain‐fed agriculture and bare ground (badlands) is nonlinear and exhibits a threshold effect. The runoff rises dramatically when more than 60% of the rangeland is removed. For groundwater this threshold lies at an 80% decrease in rangeland. Copyright © 2009 John Wiley & Sons, Ltd.
Northern Hemisphere geography of ice‐covered rivers
Authors: Bennett K. E. , Prowse T. D. 
Published: December 2009

AbstractAlthough river ice is a major component of the cryosphere and is particularly important to many river processes, including extreme events, its full geographical coverage has never been documented. Recognizing that the freeze‐up and break‐up of river ice is closely linked to the timing of 0 °C air temperatures, this study analyses the spatial extent of river networks relative to the location of three 0 °C isotherm periods. These were defined to represent a suite of ice‐affected conditions that would be experienced for 6, 3 or 0·5 month periods, the briefest interval possibly leading only to a very thin and transient ice cover or simply border/frazil ice formation. Four different GIS databases were used to represent the river networks. The percentages of the total Northern Hemisphere land mass (average river network) influenced by cold temperatures conducive to ice formation were 52, 45 and 25 (56, 47 and 28), respectively. The related southern position of the isotherms ranged from 33°N, 35°N and 50°N in central North America to a nearly consistent 27°N for Eurasia, reflecting the influence of the high‐elevation central plateau region. Also identified are the lengths of major rivers that fall within the three 0 °C isotherm boundaries. Included are some of the world's largest rivers including the Lena, Mackenzie, Ob, Yellow, Yukon and Yenisey rivers, although their percentage of ice‐affected coverage varied for the three isotherm periods from a consistent 100% for the Lena and Yukon rivers to as little as 23% at the 6‐month interval for the Yellow River. Copyright © 2009 Her Majesty the Queen in right of Canada. Published by John Wiley & Sons, Ltd.
Pattern of declining hemoglobin concentration before cancer diagnosis
Authors: Edgren Gustaf , Bagnardi Vincenzo , Bellocco Rino , Hjalgrim Henrik , Rostgaard Klaus , Melbye Mads , Reilly Marie , Adami Hans‐Olov , Hall Per , Nyrén Olof 
Published: December 2009

AbstractAlthough anemia is widely considered an early sign of malignant disease, little is known about the pattern of hemoglobin decline before diagnosis. As an approach to understanding the duration of the preclinical phase of different types of malignant diseases, we investigated prediagnostic hemoglobin concentration changes in a large cohort of blood donors. Using a nested case‐control design, we analyzed a population‐based cohort comprising 1.1 million Scandinavian blood donors with complete follow‐up through record linkage to population and cancer registers. A total of 16,375 cancer cases were identified, for whom we selected 161,995 controls. We used conditional logistic regression to estimate the risk of cancer in relation to hemoglobin concentration during the 5 years preceding the cancer diagnosis. Hemoglobin concentration decline began already 3 years before diagnosis of stomach cancer, multiple myeloma, and lymphatic leukemia; 2 years before diagnosis of small intestinal and colon cancer as well as of Hodgkin lymphoma. A decline was evident during the last year for non‐Hodgkin lymphoma and myeloid/monocytic leukemia, whereas no change was found for cancer of the esophagus, breast or prostate. In conclusion, in this study, we have demonstrated that the pattern of declining hemoglobin concentration before cancer diagnosis varies considerably between malignancies without being a suitable screening tool for any of them. For some malignancies, however, the long duration of hemoglobin decline before clinical diagnosis suggests a substantial lead‐time with systemic effects, during which earlier diagnosis should be achievable by emerging diagnostic tools.
HIF‐1α is an unfavorable determinant of relapse in gastric cancer patients who underwent curative surgery followed by adjuvant 5‐FU chemotherapy
Authors: Nakamura Jun , Kitajima Yoshihiko , Kai Keita , Hashiguchi Kazuyoshi , Hiraki Masatsugu , Noshiro Hirokazu , Miyazaki Kohji 
Published: December 2009

AbstractAmong several chemotherapeutic agents, 5‐fluorouracil (5‐FU) has been widely used as a key drug in adjuvant chemotherapy for gastric cancer. However, no reliable marker, which predicts the response to 5‐FU in an adjuvant setting, has been identified. Hypoxia‐induced drug resistance, via upregulation of HIF‐1α, is a major obstacle in the development of effective cancer therapy. However, few clinical studies have so far assessed the relationship between the HIF‐1α expression and the chemo‐resistance of gastric cancer patients in an adjuvant setting. We established 2 HIF‐1α knockdown gastric cancer cell lines in order to clarify the role of HIF‐1α in chemo‐resistance against 5‐FU. Furthermore, expression of HIF‐1α was immunohistochemically assessed in 91 resected specimens. Sixty‐four of 91 patients received 5‐FU adjuvant chemotherapy after surgery. HIF‐1α expression was associated with the significantly shorter relapse‐free survival and disease‐specific survival in the 64 patients of adjuvant group (p = 0.026, 0.014, respectively), but not in the 27 of surgery group. Multivariate analysis showed that HIF‐1α was an independent risk factor for relapse in 64 patients in the adjuvant group (p = 0.029). In conclusion, the current study confirmed, for the first time that HIF‐1α expression is an independent risk factor for relapse in high‐risk gastric cancer patients who underwent curative surgery followed by adjuvant 5‐FU chemotherapy. A favorable effect of 5‐FU might therefore be expected in patients that do not express HIF‐1α, whereas, other types of chemotherapy or additional treatments, such as HIF‐1α inhibitors, should be considered in patients that do express HIF‐1α.
Coarse‐grained model of nucleic acid bases
Authors: Maciejczyk Maciej , Spasic Aleksandar , Liwo Adam , Scheraga Harold A. 
Published: December 2009

AbstractAtomistic simulations of nucleic acids are prohibitively expensive and, consequently, reduced models of these compounds are of great interest in the field. In this work, we propose a physics‐based coarse‐grained model of nucleic‐acid bases in which each base is represented by several (3–5) interaction centers. van der Waals interactions are modeled by Lennard‐Jones spheres with a 12–6 potential energy function. The charge distribution is modeled by a set of electric dipole moments located at the centers of the Lennard‐Jones spheres. The method for computing the Lennard‐Jones parameters, electric dipole moments (their magnitude and orientation) and positions of the interaction centers is described. Several models with different numbers of interaction centers were tested. The model with three‐center cytosine, four‐center guanine, four‐center thymine, and five‐center adenine satisfactorily reproduces the canonical Watson–Crick hydrogen bonding and stacking interaction energies of the all‐atom AMBER model. The computation time with the coarse‐grained model is reduced seven times compared with that of the all‐atom model. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Parameterization of the torsional potential for calix[4]arene‐substituted poly(thiophene)s
Authors: Preat Julien , Rodríguez‐Ropero Francisco , Torras Juan , Bertran Oscar , Zanuy David , Alemán Carlos 
Published: December 2009

AbstractThree different strategies have been followed to develop the torsional force‐field parameters of the inter‐ring dihedral angles for calix[4]arene‐substituted poly(thiophene)s, a family of highly sensitive ion receptors. These procedures, which are based on the rotational profiles calculated using quantum mechanical methods, differ in the complexity of the model compounds and the processing applied to the quantum mechanical energies before the fitting. The performance of the three sets of developed parameters, which are essentially compatible with the General Amber Force Field, has been evaluated by computing the potential of mean forces for the inter‐ring rotation of 2,2′‐bithiophene, and its substituted analog bearing a calix[4]arene group in different environments. Finally, the ability of the new sets of torsional parameters to describe a calix[4]arene‐substituted poly(thiophene) in tetrahydrofuran solution has been checked using Molecular Dynamics simulations. Specifically, the molecular shape, the polymer conformation, and the effects of the Na+ions trapped in the cavity of the receptor have been examined. Although the potential derived from unsubstituted 2,2′‐bithiophene is able to reproduce the experimental free energies of the minima, the overall results indicate that the parameters derived from the analog bearing a calix[4]arene group provide the best description of the systems under study. This should be attributed to the strong constraints found in complex substituted poly(thiophene)s, which require parameterization strategies able to capture all the interactions and phenomena involved in their inter‐ring rotations. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Youth exposed to violence: the role of protective factors
Authors: Howard Kimberly A.S. , Budge Stephanie L. , McKay Kevin M. 
Published: December 2009

AbstractUsing a sample of 174 inner‐city urban high school students, this study examined the degree to which family and peer support would moderate the negative impact of exposure to violence on academic performance, symptoms of distress, and persistence intentions. Over 94% of the students reported having been exposed to at least one form of community violence at some point in their lives. Using hierarchical linear regression, the results indicated that family support provided a protective‐stabilizing moderating effect between exposure to violence and symptoms of distress. Peer support was found to have a protective‐stabilizing moderating effect between exposure to violence and persistence intentions. Although exposure to violence and persistence intentions were both related to grade point average, family and peer support were not found to moderate the impact of violence exposure and grades. © 2009 Wiley Periodicals, Inc.
Thrombospondin type I domain containing 7A (THSD7A) mediates endothelial cell migration and tube formation
Authors: Wang Chieh‐Huei , Su Pei‐Tsu , Du Xiao‐Yan , Kuo Meng‐Wei , Lin Chia‐Yi , Yang Chung‐Chi , Chan Hau‐Shien , Chang Shing‐Jyh , Kuo Calvin , Seo Kyunga , Leung Lawrence L. , Chuang Yung‐Jen 
Published: December 2009

AbstractAngiogenesis is a highly organized process controlled by a series of molecular events. While much effort has been devoted to identifying angiogenic factors and their reciprocal receptors, far less information is available on the molecular mechanisms underlying directed endothelial cell migration. To search for novel proteins that participate in this process, we used the serial analysis of gene expression (SAGE) transcript profiling approach to identify genes that are selectively expressed in endothelial cells (ECs). Two EC SAGE libraries were constructed from human umbilical vein and artery ECs to enable data‐mining against other non‐ECs. A novel endothelial protein, Thrombospondin Type I Domain Containing 7A (THSD7A), with preferential expression in placenta vasculature and in human umbilical vein endothelial cells (HUVECs) was identified and targeted for further characterization. Overexpression of a THSD7A carboxyl‐terminal fragment in HUVECs inhibited cell migration and disrupted tube formation, while suppression of THSD7A expression enhanced HUVEC migration and tube formation. Immunohistological analysis revealed that THSD7A was expressed at the leading edge of migrating HUVECs, and it co‐localized with αVβ3 integrin and paxillin. This distribution was dispersed from focal adhesions after disruption of the actin cytoskeleton, suggesting the involvement of THSD7A in cytoskeletal organization. Our results show that THSD7A is a novel placenta endothelial protein that mediates EC migration and tube formation, and they highlight its potential as a new target for anti‐angiogenic therapy. J. Cell. Physiol. 222: 685–694, 2010. © 2009 Wiley‐Liss, Inc.
Vertebral body innervation: Implications for pain
Authors: Buonocore Michelangelo , Aloisi Anna Maria , Barbieri Massimo , Gatti Anna Maria , Bonezzi Cesare 
Published: December 2009

AbstractVertebral fractures often cause intractable pain. To define the involvement of vertebral body innervation in pain, we collected specimens from male and female patients during percutaneous kyphoplasty, a procedure used for reconstruction of the vertebral body. Specimens were taken from 31 patients (9 men and 22 women) suffering high‐intensity pain before surgery. In total, 1,876 histological preparations were obtained and analysed. Immunohistochemical techniques were used to locate the nerves in the specimens. The nerve fibres were labelled by indirect immunofluorescence with the primary antibody directed against Protein Gene Product 9.5 (PGP 9.5), a pan‐neuronal marker; another primary antibody directed against type IV collagen (Col IV) was used to identify vessels and to determine their relationship with vertebral nerve fibres. The mean percentage of samples in which it was possible to identify nerve fibres was 35% in men and 29% in women. The percentages varied depending on the spinal level considered and the sex of the subject, nerve fibres being mostly present around vessels (95%). In conclusion, there is scarce innervation of the vertebral bodies, with a clear prevalence of fibres located around vessels. It seems unlikely that this pattern of vertebral body innervation is involved in vertebral pain or in pain relief following kyphoplasty. J. Cell. Physiol. 222: 488–491, 2010. © 2009 Wiley‐Liss, Inc.
Improving Gene Delivery Efficiency of Bioreducible Poly(amidoamine)s via Grafting with Dendritic Poly(amidoamine)s
Authors: Xue Ya‐Nan , Liu Min , Peng Lin , Huang Shi‐Wen , Zhuo Ren‐Xi 
Published: December 2009

AbstractDendritic poly(amidoamine)s (PAMAM)s were introduced into the side chains of disulfide‐containing poly(amidoamine)s via repetitive Michael addition and amidation. The bioreducible poly(amidoamine)s grafted with dendritic polyamidoamines showed high buffer capacity, low cytotoxicity and strong DNA binding ability at low N/P ratio. They were able to condense DNA into small sized polycation/DNA complexes, which degraded and released the incorporated DNA under reductive conditions. In comparison to the original disulfide‐containing poly(amidoamine) with aminoethyl side chain, the grafting of the bioreducible poly(amidoamine) with dendrimer greatly improved the transfection efficiencies of 293T and HeLa cells with foreign DNA at various N/P ratios. The structure–gene delivery property relations of dendrimer‐grafted polycations will provide valuable insight into the design of highly efficient and less toxic polycationic gene carriers.magnified image
Surface Interpenetrating Networks of Poly(ethylene terephthalate) and Polyamides for Effective Biocidal Properties
Authors: Liu Song , Zhao Nan , Rudenja Sergei 
Published: December 2009

AbstractPoly(ethylene terephthalate) (PET) fabrics were modified by diffusing vinyl amide monomers, divinyl crosslinker N,N′‐methylenebisacrylamide (MBA) and photoinitiator benzophenone (BP) into the surface of the PET substrate, which was swollen in a mutual solvent. Subsequent in situ photo‐polymerization resulted in the stable entrapment of the polyamides within the surface of the PET. The PET/polyamide systems produced by this technique were physically inseparable except by melting or dissolving PET. It is referred to as a sequential interpenetrating polymer network (IPN): thermoplastic semi‐IPN. Analyses of these materials by infrared spectroscopy, X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) confirmed the successful incorporation of polyamide and revealed that the polyamide is also uniformly distributed along the PET yarns. Modulated differential scanning calorimetry (MDSC) indicated a certain degree of phase‐mixed structure between PET and polyacrylamide, despite the thermodynamic incompatibility of two polymers, which could be induced to separate upon heating above the melting point of PET. These materials were stable upon Soxhlet extraction with distilled water for 72 h, and also with methanol for 24 more hours. After being converted to N‐halamine via chlorine bleaching, these materials can bring 100% reduction of the hospital acquired methicillin‐resistant Staphylococcus aureus within 10 min contact.magnified image
Dihydroxyaluminum Carboxylate Nanoparticles With Narrow Size Distribution: Synthesis, Characterization and Use for High Optical Transparency Protective Polymeric Coatings
Authors: Khalil Hazem , Gläsel Hans‐Jürgen , Wennrich Luise , Prager Andrea , Buchmeiser Michael R. 
Published: December 2009

AbstractNano‐sized bis(dihydroxyaluminum)maleate particles (ALMAL) were prepared via a high‐temperature precipitation reaction from different Al‐alkoxides and maleic acid in different solvents. Variations in the reactants were carried out to identify the optimum reaction conditions that lead to particles <30 nm in diameter with narrow particle size distributions and without formation of a secondary amorphous phase. A disc centrifuge was used to characterize the particles in terms of particle size distribution. ALMAL‐containing, epoxy‐based nanocomposites were prepared with ALMAL‐loadings up to 30 wt.‐% and thermally cured. The cured coatings possessed excellent scratch and abrasion resistance, surface hardness and were highly transparent (T>95%). In order to study the effect of the nature of nanoparticles on the final properties of the coatings, aluminum malate (ALMALAT), and aluminum terephthalate (ALTEREPHTHAL) nanoparticles as well as the corresponding composite coatings were prepared and characterized. For comparison, surface‐modified silica nanoparticles were used to evaluate the mechanical and optical behavior of the produced nanocomposite coatings.magnified image
Small, Stable, and Monodispersed Bubbles Encapsulated with Biopolymers
Authors: Park Jai Il , Tumarkin Ethan , Kumacheva Eugenia 
Published: December 2009

AbstractA microfluidic route to producing small (<10 µm) bubbles with a narrow size distribution and long‐time (at least, up to one month) stability is reported. The bubbles are encapsulated with a protein‐polysaccharide shell. The strategy includes the following events, occurring in sequence: (i) a microfluidic generation of bubbles from a mixture of CO2 and a minute amount of gases with low solubility in water, in an aqueous solution of lysozyme and sodium alginate; (ii) the dissolution of CO2 leading to the shrinkage of bubbles and a local increase in acidity of the medium; (iii) the deposition of lysozyme at the gas–water interface triggered by the local decrease in pH; (iv) the deposition of alginate onto the lysozyme shell, due to the electrostatically driven complexation of alginate with lysozyme.magnified image
Molecular analysis reveals a genetic basis for the phenotypic diversity of metaplastic breast carcinomas
Authors: Geyer Felipe C , Weigelt Britta , Natrajan Rachael , Lambros Maryou BK , de Biase Dario , Vatcheva Radost , Savage Kay , Mackay Alan , Ashworth Alan , Reis‐Filho Jorge S 
Published: December 2009

AbstractCancers may be composed of multiple populations of submodal clones sharing the same initiating genetic lesions, followed by the acquisition of divergent genetic hits. Intra‐tumour genetic heterogeneity has profound implications for cancer clinical management. To determine the extent of intra‐tumour genetic heterogeneity in breast cancers, and whether the morphological diversity of breast cancers is underpinned by divergent genetic aberrations, we analysed the genomic profiles of microdissected, morphologically distinct components of six metaplastic breast carcinomas, tumours characterized by the presence of morphological areas with divergent differentiation. Each morphologically distinct component was separately microdissected and subjected to high‐resolution microarray‐based comparative genomic hybridization. Each component was also analysed by immunohistochemistry and in situ hybridization. Clonal relationship between the distinct components was tested by TP53 sequencing and human androgen receptor (HUMARA) X‐chromosome inactivation assay. In the majority of cases, all morphologically distinct components from each case were clonal and displayed remarkably similar genetic profiles. In two cases, however, morphologically distinct components harboured specific genetic aberrations. In an adenosquamous carcinoma, the differences were such that only 20% of the genome harboured similar copy number changes. The squamous component displayed EGFR gene amplification, EGFR over‐expression and lack of expression of hormone receptors, whereas the lobular component displayed the reverse pattern. The components of a biphasic spindle cell carcinoma harboured similar gains, losses, amplifications of 9p23 and 17q12 (HER2) and identical TP53 mutations, suggesting that these were relatively early events in the development of this tumour; however, each component displayed divergent focal amplifications. Importantly, the metastatic deposit of this case, despite harbouring a TP53 mutation identical to that found in the primary tumour, harboured additional specific focal amplifications. This proof‐of‐principle study provides direct evidence of intra‐tumour genetic heterogeneity in breast cancers, and shows that in some cases morphological diversity may be underpinned by distinct genetic aberrations. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.