bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Importance of Lake Morphometry for the Structureand Function of Lakes
Authors: Håkanson Lars 
Published: July 2005

AbstractThis work demonstrates quantitatively and in a comprehensive way that the size and form of lakes regulate many general transport processes, such as sedimentation, resuspension, diffusion, mixing, burial and outflow, which in turn regulate many abiotic state variables, such as concentrations of phosphorus, suspended particulate matter, many water chemical variables and water clarity, which in turn regulate primary production, which regulate secondary production, for example of zooplankton and fish. Such relationships are discussed not qualitatively but quantitatively using a new generation of validated dynamic ecosystem models (LakeWeb and LakeMab) based on mechanistic principles. It has been shown by critical model tests (including blind tests using data covering wide limnological ranges) that these models give predictions that agree well with empirical data. This should lend credibility to the results presented in this work, which would have been very difficult to obtain using traditional methods with extensive field studies in a few lakes. Simulations have been carried out where the inflow of phosphorus is held constant and the consequences simulated for small, large, shallow and deep lakes. There are striking differences in total phosphorus (TP) concentrations and trophic state (from 10 to 100 µg TP/l) and hence also in changes in many variables characterizing lake structure and function, such as Secchi depth, suspended particulate matter, pH, water temperature, chlorophyll, algal volume, macrophyte cover; as well as production and biomasses of benthic algae, bacterioplankton, macrophytes, herbivorous zooplankton, predatory zooplankton, zoobenthos, prey fish and predatory fish. These changes have been quantified in a comprehensive manner in this work and the approach to calculate such changes are basic for an understanding of how different lakes react to changes in nutrient loading (eutrophication). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adsorbed layers of oriented fibronectin: A strategy to control cell–surface interactions
Authors: Calonder Claudio , Matthew Howard W. T. , Van Tassel Paul R. 
Published: July 2005

AbstractFibronectin (Fn) is a matrix protein known to induce cell attachment and spreading through its cell binding site and related synergy sites. Fn‐coated surfaces are therefore useful in tissue engineering and other cell contacting applications, but a problem with many immobilization strategies is a random distribution of molecular orientations. We sought to control Fn orientation, and thus enhance the availability of its cell binding site, by immobilizing Fn via a carboxymethyl dextran layer onto which are chemically attached monoclonal antibodies specific to a region near to Fn's C terminus (and thus away from the cell binding site). Using optical waveguide lightmode spectroscopy, we show the presence of chemically coupled antibodies to yield a considerably denser and thicker Fn layer, consistent with a more vertically aligned protein. Human umbilical vein endothelial cells spread significantly faster, and in a more spherically symmetric way, on an oriented Fn layer (i.e., in the presence of immobilized monoclonal antibodies) as compared with a control Fn layer (i.e., in the absence of bound antibodies). However, we observe human umbilical vein endothelial cell spreading on the oriented Fn layer to be similar to that on a Fn layer in the absence of a carboxymethyl dextran layer, suggesting that although orienting Fn is a promising strategy, coupling strategies using linkers other than dextran may be needed. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Structural evaluation of radially expandable cardiovascular stents encased in a polyurethane film
Authors: Trigwell Steve , De Samiran , Sharma Rajesh , Mazumder Malay K. , Mehta Jawahar L. 
Published: August 2005

AbstractA method of encasing cardiovascular stents with an expandable polyurethane coating has been developed to provide a smooth homogeneous inner wall allowing for a confluent growth of endothelial cells. In this design, the metal wire stent structure is completely covered by the polyurethane film, minimizing biocorrosion of the metal (stainless steel or nitinol), and providing a homogeneous surface for surface treatment and incorporation of various eluting drugs to prevent platelet aggregation while supporting endothelialization. The polyurethane surface was treated with a helium plasma for sterilization and promotes growth of cells. The article details the performance of the coated film to expand with the metal stent up to 225% during deployment. Stress/strain behavior of polyurethane films, subsequent plasma treatment of the surface, and the adhesion of the coating to the stent structure upon expansion are presented. A film of less than 25 μm was found to be sufficient for corrosion resistance and flexibility without producing any excess stress on the stent structure. Straining the film to 225% and plasma modification did not affect the mechanical and surface properties, but allowed for improved biocompatibility as determined by the critical surface tension, surface chemistry, and roughness. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Role of HER‐2/neu signaling in sensitivity to tumor necrosis factor‐related apoptosis‐inducing ligand: Enhancement of TRAIL‐mediated apoptosis by amiloride
Authors: Kim Ki M. , Lee Yong J. 
Published: July 2005

AbstractTumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) has been shown to induce apoptosis in numerous transformed cell lines but not in most normal cells. Although this selectivity offers a potential therapeutic application in cancer, not all cancers are sensitive to TRAIL‐mediated apoptosis. In this study, we observed that amiloride, a current clinically used diuretic drug, which had little or no cytotoxicity, sensitized TRAIL‐resistant human prostate adenocarcinoma LNCaP and human ovarian adenocarcinoma SK‐OV‐3 cells. The TRAIL‐mediated activation of caspase, and PARP cleavage, were promoted in the presence of amiloride. Western blot analysis showed that combined treatment with TRAIL and amiloride did not change the levels of TRAIL receptors (DR4, DR5, and DcR2) and anti‐apoptotic proteins (FLIP, IAP, and Bcl‐2). However, amiloride dephosphorylated HER‐2/neu tyrosine kinase as well as Akt, an anti‐apoptotic protein. Interestingly, amiloride also dephosphorylated PI3K and PDK‐1 kinases along with PP1α phosphatase. In vitro kinase assay revealed that amiloride inhibited phosphorylation of kinase as well as phosphatase by competing with ATP. Taken together, the present studies suggest that amiloride enhances TRAIL‐induced cytotoxicity by inhibiting phosphorylation of the HER‐2/neu‐PI3K‐Akt pathway‐associated kinases and phosphatase. © 2005 Wiley‐Liss, Inc.
Enhancing crop yields in the developing countries through restoration of the soil organic carbon pool in agricultural lands
Authors: Lal R. 
Published: August 2005

AbstractFood production in developing countries, estimated at 1223 million metric tons (Mg), must be increased by 778 million Mg or 2·5 per cent y−1 between 2000 and 2025 to meet the needs of an increased population and projected change in diet. Among numerous options, the one based on enhancing soil quality and agronomic productivity per unit area through improvement in soil organic carbon pool has numerous ancillary benefits. The available data show that crop yields can be increased by 20–70 kg ha−1 for wheat, 10–50 kg ha−1 for rice, and 30–300 kg ha−1 for maize with every 1 Mg ha−1 increase in soil organic carbon pool in the root zone. Adoption of recommended management practices on agricultural lands and degraded soils would enhance soil quality including the available water holding capacity, cation exchange capacity, soil aggregation, and susceptibility to crusting and erosion. Increase in soil organic carbon pool by 1 Mg ha−1 y−1 can increase food grain production by 32 million Mg y−1 in developing countries. While advancing food security, this strategy would also off‐set fossil fuel emissions at the rate of 0·5 Pg C y−1 through carbons sequestration in agricultural soils of developing countries. Copyright © 2005 John Wiley & Sons, Ltd.
Reservoirs in Tigray (Northern Ethiopia): characteristics and sediment deposition problems
Authors: Haregeweyn N. , Poesen J. , Nyssen J. , De Wit J. , Haile M. , Govers G. , Deckers S. 
Published: August 2005

AbstractIn Tigray (Northern Ethiopia, significant achievements were made, mainly from 1994 to 2002), on the development of agriculture through irrigation by employing seasonally harvested runoff using earth dams. However, most of the implemented schemes are not serving the intended purpose well because of constraints associated with both pre‐ and post‐implementation. Sediment deposition in reservoirs is a serious off‐site consequence of soil erosion in the region. However, the extent of the problem is not well studied. Moreover, there are no sufficient and reliable sediment‐yield data for Northern Ethiopia, which are important for designing new reservoirs and for implementing soil conservation practices. This study addresses those problems by undertaking: (1) a survey and evaluation of the general characteristics and problems of 54 recently built reservoirs and the characteristics of their respective catchments; and (2) a detailed sediment survey in ten reservoirs and related catchment characteristics. A field survey in 2002–2003, a review of technical reports and interviews were the bases for this study.Most of the reservoirs are under risk of insufficient inflow, excessive seepage and sediment deposition. These problems are mainly attributed to the use of a poor database on hydrology and sediment yield, and the lack of adaptable methodologies for assessing controlling factors at the planning stage.The reservoir survey, which is the first of its kind in Ethiopia, also indicates that specific sediment yield (SSY) varies significantly between catchments: i.e. from 237 to 1817 t km−2 y−1 with an average of 909 ( ± 500) t km−2 y−1. The high spatial variability is mainly associated with differences in lithology, cover, extent of gully network and human activities. Therefore, adapting an average SSY value for the whole region is not recommended for future planning purposes. The sediment deposition problem is significant: i.e. 70 per cent of the study reservoirs have important siltation problems so that they will end their useful life well before the dam design period. Hence, sediment management in reservoirs could be an effective approach towards maintaining the existing storage capacity.For the realization of sustainable land and water development in Tigray, sufficient and reliable database building, development and standardization of appropriate methodologies for predicting sediment yield and capacity building of designers needs to be given top priority. Moreover, awareness creation among policy makers, donors and beneficiaries is also important for action. Copyright © 2005 John Wiley & Sons, Ltd.
Hybrid Nanogels with Physical and Chemical Cross‐Linking Structures as Nanocarriers
Authors: Morimoto Nobuyuki , Endo Takao , Ohtomi Michiko , Iwasaki Yasuhiko , Akiyoshi Kazunari 
Published: August 2005

AbstractSummary: Polymerizable nanogels were prepared by self‐assembly of cholesteryl group‐bearing pullulan (CHP) with methacryloyl groups (CHPMA). The CHPMA nanogel was polymerized with 2‐methacryloyloxyethyl phosphorylcholine (MPC) by radical polymerization in dilute aqueous solution. The solution properties of the polymers in water were investigated by TEM, SEC‐MALS, and fluorescence quenching technique. Monodispersed hybrid nanogels of CHPMA‐MPC (CM nanogels) (25–30 nm in radius of gyration) were obtained by using CHPMA nanogel as a seed‐nanogel. CM nanogels have a dual cross‐linking structure that is physically cross‐linked with the cholesteryl groups and chemically cross‐linked with the MPC polymer chains. CM nanogels trap heat‐denatured carbonic anhydrase B (CAB) and prevent their aggregations. The nanogels maintained the ability of trapping and releasing enzymes by host‐guest interaction of cholesteryl group and cyclodextrin.Schematic illustration of hybrid nanogel preparation.magnified imageSchematic illustration of hybrid nanogel preparation.
Temperature Sensitive Behavior of Poly(N‐isopropylacrylamide) Grafted Onto Electron Beam‐Irradiated Poly(propylene)
Authors: Bucio Emilio , Burillo Guillermina , Adem Esbaide , Coqueret Xavier 
Published: July 2005

AbstractSummary: N‐Isopropylacrylamide (NIPAAm) was graft‐polymerized from its acetone solution onto poly(propylene) (PP) films, after electron‐beam irradiation in the presence of air oxygen. The effects of pre‐irradiation dose as well as monomer concentration, reaction temperature and reaction time on the grafting efficiency were investigated. Typical conditions for achieving maximum grafting yield were observed for 1 M monomer concentration, after PP pre‐irradiation with a 300 kGy dose and a reaction temperature of 50 °C. The location of the graft polymerization was examined by different methods including measurements of dimensional variations, calorimetry, SEM and AFM. The temperature‐responsive behavior of grafted copolymer was studied by swelling and contact angle measurements at different temperatures.Temperature dependence of the swelling ratio in water as a function of temperature.magnified imageTemperature dependence of the swelling ratio in water as a function of temperature.
Swelling Behavior and Complex Formation Ability of Ternary Amphoteric Gels based on Allylamine Derivatives and Maleic Acid
Authors: Ibraeva Zhanar E. , Hahn Mathias , Jaeger Werner , Laschewsky Andre , Bimendina Larisa A. , Kudaibergenov Sarkyt E. 
Published: August 2005

AbstractSummary: The swelling behavior of an amphoteric gel composed of 50 mol‐% of maleic acid (MA), 25 mol‐% of N,N′‐dimethyldiallylammonium chloride (DMDAAC) and 25 mol‐% of diallylamine (DAA) was studied in aqueous and aqueous‐salt solutions. The isoelectric point (IEP) of the MA‐DMDAAC‐DAA gel determined from swelling experiments was about pH 4.6. Considerable gel swelling with increasing ionic strength was observed at the IEP. Dynamic swelling properties of the amphoteric gel in water with and without added salt were measured at various pH values including the IEP. The swelling behavior of the amphoteric gel was found to depend on the ionization state of the functional groups. It can be described by either a relaxation‐controlled or non‐Fickian (anomalous) mechanism. Swelling‐deswelling properties of the amphoteric gel were also studied in mixtures of water and organic solvents. The amphoteric gel was able to complex sodium poly(styrene sulfonate), sodium lauryl sulfate, the cationic drug richlocain, and the bivalent transition metal ions Cu2+, Ni2+, Co2+, and Zn2+. The sorption of polyelectrolyte, surfactant, drug, and metal ions by the amphoteric gel is accompanied by the contraction of the gel network. Partial release of the cationic drug molecules entrapped into the gel volume takes place at the IEP of the amphoteric gel with low activation energy, while neither the anionic polyelectrolyte nor the surfactants are released from the gel interior at the IEP. The swelling‐shrinking behavior of gel‐polyelectrolyte and gel‐surfactant complexes in dependence of pH and ionic strength of the outer solution is similar.
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Copolymerization of Propene and 5‐Vinyl‐2‐Norbornene: A Simple Route to Polar Poly(propylene)s
Authors: Sarazin Yann , Fink Gerhard , Hauschild Klaus , Bochmann Manfred 
Published: July 2005

AbstractSummary: The metallocenes rac‐C2H4(Ind)2ZrCl2 (1), rac‐Me2Si(Ind)2ZrCl2 (2), and rac‐Me2Si(2‐Me‐benz[e]Ind)2ZrCl2 (3) efficiently copolymerize propene and 5‐vinyl‐2‐norbornene (VNB). 1 and 2 give a high VNB content and high productivities, whereas 3 gives moderate incorporation. Surprisingly, precatalysts 1 and 2, which have very closely related structures, showed very different reactivities toward VNB, with 1 having a greater affinity for VNB than for propene. The copolymers are quantitatively converted into polyolefins with polar functionalities.
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Novel Cross‐Linked Films Prepared from Hyperbranched Poly(amine‐ester)
Authors: Wei Xiu‐Zhen , Zhu Bao‐Ku , Xiao Ling , Xu You‐Yi , Geckeler Kurt E. 
Published: July 2005

AbstractSummary: Novel hyperbranched poly(amine‐ester) (HPAE) cross‐linked films were prepared by cross‐linking the terminal hydroxyl groups of HPAE using glutaraldehyde (GA). Atom force microscope and scanning electron microscope revealed their smooth surfaces, dense and homogenous matrices. Property characterizations indicated that these cross‐linked films had good hydrophilicity, relative low protein adsorption, and high tensile strength. Also, their swelling behavior varied with the solvent.Structure of the hyperbranched poly(amine‐ester).magnified imageStructure of the hyperbranched poly(amine‐ester).
Synthesis and Characterization of Helix‐Coil Diblock Copolymers with Controlled Supramolecular Architectures in Aqueous Solution
Authors: Zhang Jie , Yu Zhenning , Wan Xinhua , Chen Xiaofang , Zhou Qifeng 
Published: July 2005

AbstractSummary: A series of helix‐coil diblock copolymers based on poly(ethylene oxide) and optically active helical poly{(+)‐2,5‐bis[4′‐((S)‐2‐methylbutoxy)phenyl]styrene} (PMBPS) were synthesized via atom transfer radical polymerization (ATRP). The synthetic methodology permitted straightforward preparation of the diblock copolymers with relatively low polydispersities and a broad range of compositions and molecular weights. Depending on the composing block length and the initial concentration, the copolymers self‐assembled into different supramolecular structures in aqueous solution, including spherical micelles, vesicles, multilamellar vesicles, large compound vesicles, and tubules.Schematic representation of the synthesis of PEO‐b‐PMBPS block copolymers and their aggregation in aqueous solution.magnified imageSchematic representation of the synthesis of PEO‐b‐PMBPS block copolymers and their aggregation in aqueous solution.
Propagation of a hydraulic fracture parallel to a free surface
Authors: Zhang X. , Jeffrey R. G. , Detournay E. 
Published: July 2005

AbstractThis paper analyses the plane strain problem of a fracture, driven by injection of an incompressible viscous Newtonian fluid, which propagates parallel to the free surface of an elastic half‐plane. The problem is governed by a hyper‐singular integral equation, which relates crack opening to net pressure according to elasticity, and by the lubrication equations which describe the laminar fluid flow inside the fracture. The challenge in solving this problem results from the changing nature of the elasticity operator with growth of the fracture, and from the existence of a lag zone of a priori unknown length between the crack tip and the fluid front. Scaling of the governing equations indicates that the evolution problem depends in general on two numbers, one which can be interpreted as a dimensionless toughness and the other as a dimensionless confining stress. The numerical method adopted to solve this non‐linear evolution problem combines the displacement discontinuity method and a finite difference scheme on a fixed grid, together with a technique to track both crack and fluid fronts. It is shown that the solution evolves in time between two asymptotic similarity solutions. The small time asymptotic solution corresponding to the solution of a hydraulic fracture in an infinite medium under zero confining stress, and the large time to a solution where the aperture of the fracture is similar to the transverse deflection of a beam clamped at both ends and subjected to a uniformly distributed load. It is shown that the size of the lag decreases (to eventually vanish) with increasing toughness and compressive confining stress. Copyright © 2005 John Wiley & Sons, Ltd.
A unified formulation for continuum mechanics applied to fluid–structure interaction in flexible tubes
Authors: Greenshields C. J. , Weller H. G. 
Published: July 2005

AbstractThis paper outlines the development of a new procedure for analysing continuum mechanics problems with a particular focus on fluid–structure interaction in flexible tubes. A review of current methods of fluid–structure coupling highlights common limitations of high computational cost and solution instability. It is proposed that these limitations can be overcome by an alternative approach in which both fluid and solid components are solved within a single discretized continuum domain. A single system of momentum and continuity equations is therefore derived that governs both fluids and solids and which are solved with a single mesh using finite volume discretization schemes. The method is validated first by simulating dynamic oscillation of a clamped elastic beam. It is then applied to study the case of interest—wave propagation in highly flexible tubes—in which a predicted wave speed of 8.58 m/s falls within 2% of an approximate analytical solution. The method shows further good agreement with analytical solutions for tubes of increasing rigidity, covering a range of wave speeds from those found in arteries to that in the undisturbed fluid. Copyright © 2005 John Wiley & Sons, Ltd.
The risk of cancer in twins: A report from the childhood cancer survivor study
Authors: Kadan‐Lottick Nina S. , Kawashima Toana , Tomlinson Gail , Friedman Debra L. , Yasui Yutaka , Mertens Ann C. , Robison Leslie L. , Strong Louise C. 
Published: August 2005

AbstractBackgroundTwin concordance studies help evaluate the contribution of genetic factors in childhood cancers, but previous reports have primarily focused on leukemia because of the rarity of other malignancies. In the current report, a large cohort of childhood cancer survivors was used to: (1) describe twin concordance patterns for a range of cancers, (2) calculate the standardized incidence rates of cancers in twins, and (3) describe clinical features and outcomes of concordant twins.ProcedureCancer family history was obtained on the 211 twins participating in the Childhood Cancer Survivor Study (CCSS) (14,352 participants surviving ≥5 years after a malignancy diagnosed at <21 years during January 1, 1970–December 31, 1986) to calculate probandwise twin concordance rates and standardized incidence ratios (SIRs) using Surveillance, Epidemiology, and End‐Results data.ResultsSeven monozygotic twin pairs were concordant for cancer (six for leukemia, one for non‐Hodgkin lymphoma), yielding probandwise concordance rates of 9.5%, 20.7%, and 20.0% for all cancer, leukemia, and non‐Hodgkin lymphoma (NHL), respectively. No concordance was observed among dizygotic twins or for dissimilar cancers. The SIR in monozygotic twins was 23.3 (95% CI = 11.1–48.9) for all cancer, 112.4 (95% CI = 50.5–250.1) for leukemia, and 40.5 (5.7–287.5) for NHL. Concordant twins were similar in age at diagnosis and vital status.ConclusionsTwin concordance for cancer is largely restricted to monozygotic twins and hematological malignancies, consistent with in utero malignancy transmission demonstrated by others. Our data support clinical monitoring of the twins of cases with hematological malignancies, and does not contribute evidence for genetic factors in other cancers. Pediatr Blood Cancer 2006, 46:476–481. © 2005 Wiley‐Liss, Inc.