bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, characterization, and antibacterial activities of a novel nanohydroxyapatite/zinc oxide complex
Authors: Zhou Gang , Li Yubao , Xiao Wei , Zhang Li , Zuo Yi , Xue Jing , Jansen John A. 
Published: September 2007

AbstractNanohydroxyapatite (n‐HA)/zinc oxide (ZnO) complex was synthesized by a direct precipitation method, and the antibacterial capability and antibacterial mechanism of this complex were investigated in this article. Transmission electron microscope (TEM), Fourier transform infrared, X‐ray photoelectronic spectroscopy (XPS), and X‐ray diffraction (XRD) were used to analyze the materials. In addition, the antibacterial capacity of n‐HA/ZnO complex was examined by bacteriolytic plate, inhibition effect, and antibacterial rate assays under light or without light. Furthermore, agarose gel electrophoresis of plasmid DNA (pUC18) was used to study biocidal action of this complex. The results of TEM observation revealed that the complex's rods had a single crystalline obelisk‐like hexagonal wurtzite structure and the crystal retained the nanometer size. XRD analysis indicated that the phase of ZnO appeared and the lattice parameters of n‐HA and ZnO changed. XPS spectra showed that the bonding energy of Ca, P, and O atoms changed in the complex. The analyses also showed that the two phases of ZnO and n‐HA combined closely. Further, the results of the antibacterial test revealed that this complex possessed strong antibacterial capability; the antibacterial rate was 99.45% to S. aureus and 95.65% to E. coli under light, respectively. The antibacterial activity of this complex under light was better than without light, which was attributed to the generation of ·OH under light. From the agarose gel electrophoresis, the dissolving solution of this complex could catalyze the cleavage of pUC18. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Tailoring of multilayered core‐shell nanostructure for multicomponent administration and controllable release of biologically active ions
Authors: Gou Zhongru , Weng Wenjian , Du Piyi , Han Gaorong , Yan Weiqi 
Published: September 2007

AbstractThe biomaterials that can control the active ions delivery to enhance cell activity are regarded as promising bone regenerative materials. In this study, a new approach aiming to layer‐by‐layer (LbL) assemble the bioavailable zinc ions in the core‐shell‐like silica@octacalcium phosphate (OCP) nanosphere and to analyze its efficacy on improving controlled‐release was reported. Firstly, a pH‐responsive electrostatic interaction was used to adsorb zinc ions on silica nanospheres with different zinc concentration, which was followed by coating silica gel layer. Then the nanospheres were LbL assembled with zinc ions and silica gel alternately until the desired multilayered nanospheres were achieved. Finally, the porous OCP shells were capped onto the outside surface of the nanospheres tailored by poly(aspartic acid) sodium molecules. The ion release tests in Tris buffers in vitro indicated that zinc release was controlled by pH and storage capacity, and silicon release was regulated by the OCP shell barrier. A temporal gradient within short times and sustained‐dosage for a prolonged time toward the zinc and silicon ions could be obtained in this multilayer system. The results of this organized active ion assembly might open a promising future direction for effective delivery of trace elements in bone defect therapy. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Public–private partnerships in developing countries: are infrastructures responding to the new ODA strategy?
Authors: Pessoa Argentino 
Published: September 2007

AbstractThe developing world needs far more financing for infrastructure than can be provided by domestic public finances alone and through Official Development Aid (ODA). Around middle 1980s a new strategy based on the use of public–private agreements, relying on ODA to enhance the quality of projects, reduce risks and raise profitability was gradually implemented for the provision of infrastructures and public utilities. This paper evaluates the more typical forms of private sector involvement (PSI) and its actual importance (by type of public utility and by region) and shows that the new strategy has failed in improving the provision of infrastructures in the developing world. Copyright © 2007 John Wiley & Sons, Ltd.
Gas‐phase electrophilic addition promoted by CH3S+ CH2 ions on aromatic systems
Authors: Fileti Eudes E. , Moraes Patrícia R. P. , Domingues Leonardo , Riveros José M. 
Published: September 2007

AbstractThe gas‐phase methylenation reaction between CH3S+CH2 and alkylbenzenes, aniline, phenol and alkyl phenyl ethers, which yields [M + CH]+ and CH3SH, has been studied by Fourier transform ion cyclotron resonance (FT‐ICR) techniques and computational chemistry at the DFT level. The methylthiomethyl cation is less reactive than methoxymethyl and, unlike the latter, is unreactive toward benzene. The calculations suggest that reaction with toluene should proceed primarily by addition at the para and ortho positions resulting in a benzyl‐type ion. Reaction with aniline‐2,3,4,5,6‐d5 reveals that elimination of CH3SD is kinetically favored by a factor of 5 over elimination of CH3SH. Experiments with C6H6ND2 and theoretical calculations suggest that methylenation at the nitrogen atom is energetically favorable and likely, but the observed results may reflect some H/D scrambling, which occurs after attack at a ring position. By comparison, reaction with phenol‐2,3,4,5,6‐d5 reveals that methylenation followed by elimination of CH3SD is kinetically favored by a factor of 3.8 over elimination of CH3SH. For phenol, the theoretical calculations suggest that attack by CH3S+CH2 at the para or ortho position is the only low‐energy pathway for methylenation. However, a low‐energy pathway for hydrogen scrambling is predicted by the calculations originating from the exit complex, [CH3SH··· CH2C6H4OH]+, of reaction at a ring position. Copyright © 2007 John Wiley & Sons, Ltd.
Spiroiminodihydantoin nucleoside formation from 2′‐deoxyguanosine oxidation by [18O‐labeled] singlet molecular oxygen in aqueous solution
Authors: Martinez Glaucia Regina , Ravanat Jean‐Luc , Cadet Jean , de Medeiros Marisa Helena Gennari , Di Mascio Paolo 
Published: September 2007

AbstractThe main singlet molecular oxygen (1O2) oxidation products of free 2′‐deoxyguanosine (dGuo) in aqueous solution were identified as a pair of diastereomeric spiroiminodihydantoin 2′‐deoxyribonucleosides (dSp) together with 8‐oxo‐7,8‐dihydro‐2′‐deoxyguanosine (8‐oxodGuo). In the present work, evidence is provided from 18[1O2] and H218O labeling experiments, using HPLC‐ESI‐MS/MS, that the formation of dSp is explained by the addition of water to a reactive quinonoid intermediate, and a second reaction pathway leading to dSp involves 1O2 oxidation of initially generated 8‐oxodGuo. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of GCM bias on downscaled precipitation and runoff projections for the Serpentine catchment, Western Australia
Authors: Charles S. P. , Bari M. A. , Kitsios A. , Bates B. C. 
Published: September 2007

AbstractAn investigation has been undertaken to quantify the uncertainty in statistically downscaled catchment precipitation and runoff projections due to different climate models. A significant component of the investigation was the assessment of climate model reproduction of the seasonal (i.e. monthly) cycle of the atmospheric predictors used by a statistical downscaling model. Four climate model simulations forced by the SRES A2 emission scenario were used: the CSIRO Mk3 GCM, the CSIRO Conformal‐Cubic Atmospheric Model (CCAM, run at high spatial resolution over Australia with far‐field forcing from the Mk3 GCM), the Hadley Centre HadAM3P GCM and the Max Planck Institute ECHAM4 GCM.The non‐homogeneous hidden Markov model (NHMM), a stochastic downscaling model, was used to quantify the impacts of the projected climate change on multi‐site, daily precipitation. A catchment water balance model (LUCICAT), calibrated under existing conditions, was driven by the downscaled precipitation to produce runoff projections. Land use and potential evaporation (evapotranspiration potential) were kept fixed for the future climate in order to assess the catchment response to differences in the downscaled precipitation series.Biases in climate model reproduction of the season cycles of the atmospheric predictors used in downscaling are shown to have significant impacts on simulated precipitation, and hence runoff. The downscaled CCAM and Mk3 results project reductions in annual precipitation ranging from 12 to 14% by mid century (2035–2064), resulting in a decline in runoff ranging from 30 to 44%. Downscaling the HadAM3P output, available at the daily time step only for the period 2070–2099, produces a precipitation decline of 24% and a runoff reduction of 69%. The ECHAM4 downscaled precipitation inadequately reproduced the observed annual cycle and so was not used for runoff projection. Copyright © 2007 Royal Meteorological Society
Reversal of suppressed metabolism in prolonged cold preserved cartilage
Authors: Pylawka Tamara K. , Virdi Amarjit S. , Cole Brian J. , Williams James M. 
Published: September 2007

AbstractChondrocytes in cold preserved cartilage are metabolically suppressed. The goal of this study was to address this metabolic suppression and seek ways to reverse it. Specifically, we examined the roles of rewarming protocols and nitric oxide (NO) in this metabolic suppression. Bovine and canine full‐thickness articular cartilage explants were cultured under various temperature conditions, and NO production, proteoglycan (PG) synthesis, and cell viability were measured. Nitric oxide was shown to be negatively correlated with PG synthesis following abrupt rewarming of cold preserved osteochondral allografts. Gradual rewarming of the allograft tissue decreased NO production with higher PG synthesis. Inhibition of nitric oxide synthases (NOS) led to a decrease in NO production and a concomitant increase in PG synthesis. We were able to partially reverse metabolic suppression of cold preserved osteochondral allograft material with gradual rewarming and decrease NO production with NOS inhibition. Chondrocytes in cold preserved allograft material may be metabolically suppressed predisposing the graft to failure in vivo. Minimizing this loss of metabolic function by gradual graft rewarming and decreasing NO production by NOS inhibition at the time of graft implantation may have implications on graft survival in vivo. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:247–254, 2008
Enveloping bioabsorbable polyglycolide membrane and immobilization in achilles tendon repair: A comparative experimental study on rabbits
Authors: Pihlajamäki Harri , Tynninen Olli , Karjalainen Pertti , Rokkanen Pentti 
Published: September 2007

AbstractUsing qualitative and histoquantitative methods, we investigated the effect of immobilization versus nonimmobilization on the biodegradation process, implant‐tissue interaction, and scar formation after enveloping a rejoined rabbit Achilles tendon with a self‐reinforced polyglycolide (SR‐PGA) membrane. The soleus and gastrocnemius tendons of the right hind legs of 40 rabbits were transected. After suturing the ends, the seam was enveloped with the bioabsorbable membrane. Twenty ankles were immobilized with cast, 20 remained nonimmobilized. All nonoperated left ankles served as intact controls. During the follow‐up of 3, 6, 12, and 24 weeks, scar formation, tissue response, and membrane biodegradation were studied histologically and histomorphometrically. The amount of scar tissue, highest at 3 weeks, gradually approached intact controls. SR‐PGA degradation in both cast and noncast specimens was near complete by 24 weeks. Signs of an inflammatory process were most prominent at 3 weeks and diminished gradually by 24 weeks. No significant difference between cast and noncast specimens was noted at any time point regarding the amount of scar tissue, degradation process of PGA, or intensity of inflammatory reaction. In the present experimental setting, cast immobilization influenced neither scar formation nor speed of degradation during reunion of transected Achilles tendon ends as compared with nonimmobilization. No differences in the reunion process of the tendon ends were seen between the immobilized and nonimmobilized groups. Moreover, inflammatory cells were similar in both groups and reflected a transient tissue reaction to the membrane. Within the follow‐up, the seam area (cross‐sectional) approached that of intact controls. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:264–270, 2008
Excision of selectable marker genes from transgenic crops as a concern for environmental biosafety
Authors: Natarajan Satheesh , Turna Ján 
Published: September 2007

AbstractThe main task in the development of transgenic plants is the capability to distinguish between plant cells with an integrated transgene and the bulk of non‐transformed cells. Selectable marker genes are required to achieve this goal within the transgene, and to select for their expression. These selectable markers are mostly based on genes conferring antibiotic or herbicide resistance. The presence of the marker gene will lead to unpredictable environmental hazards, so on the basis of economic incentives and safety concerns, several methods, such as site‐specific recombination, homologous recombination and co‐transformation, have been developed to eliminate these genes from the genome after successful transformation has been achieved. Gene transfer without the incorporation of an antibiotic‐resistance marker or herbicide‐resistance marker in the host genome should convince the public with regard to the field release of transgenic organisms. Moreover, it would obviate the need for different selectable markers in subsequent rounds of gene transfer into the same host. Copyright © 2007 Society of Chemical Industry
Herpes Simplex Virus Hepatitis
Authors: Norvell John P. , Blei Andres T. , Jovanovic Borko D. , Levitsky Josh 
Published: September 2007

Abstract

Hepatitis is a rare complication of herpes simplex virus (HSV), often leading to acute liver failure (ALF), liver transplantation (LT), and/or death. Our aim was to identify variables associated with either survival or progression (death/LT), based on an analysis of cases in the literature and our institution. A total of 137 cases (132 literature, 5 institutional) of HSV hepatitis were identified. The main features at clinical presentation were fever (98%), coagulopathy (84%), and encephalopathy (80%). Rash was seen in less than half of patients. Most cases (58%) were first diagnosed at autopsy and the diagnosis was suspected clinically prior to tissue confirmation in only 23%. Overall, 74% of cases progressed to death or LT, with 51% in acyclovir-treated patients as compared to 88% in the untreated subjects (P = 0.03). Variables on presentation associated with death or need for LT compared to spontaneous survival: male gender, age >40 yr, immunocompromised state, ALT >5,000 U/L, platelet count <75 × 103/L, coagulopathy, encephalopathy, and absence of antiviral therapy. In conclusion, HSV hepatitis has a high mortality and is often clinically unsuspected. Patients who are male, older, immunocompromised, and/or presenting with significant liver dysfunction are more likely to progress to death and should thus be evaluated for LT early. Based on the frequent delay in HSV diagnosis, low risk-benefit ratio, and significantly improved outcomes, empiric acyclovir therapy for patients presenting with ALF of unknown etiology is recommended until HSV hepatitis is excluded. Liver Transpl 13:1428–1434, 2007. © 2007 AASLD.
Curing Behavior and Final Properties of Nanostructured Thermosetting Systems Modified with Epoxidized Styrene‐Butadiene Linear Diblock Copolymers
Authors: Serrano Elena , Tercjak Agnieszka , Ocando Connie , Larrañaga Maider , Parellada M. Dolores , Corona‐Galván Sergio , Mecerreyes David , Zafeiropoulos Nikolaos E. , Stamm Manfred , Mondragon Iñaki 
Published: September 2007

AbstractNanostructured thermosetting materials based on thermosetting matrices were prepared by modification of an epoxy system with linear PS‐block‐PB copolymers. The nanostructured thermosets were obtained through PS block segregation. Depending on the block‐copolymer content in the thermosets and its epoxidation degree, the PS domains can display micellar, worm‐like or hexagonally‐packed cylinder structures, retaining the stiffness of the epoxy matrix, where the hexagonally cylindrical morphology lead to a significant increase in fracture toughness. The rheokinetics of microphase separation during network formation was investigated. Nanostructures are judged to be formed by polymerization‐induced microphase separation, in marked contrast to equilibrium self‐organized structures that are preformed, with the microphases fixed via a curing reaction.magnified image
An Omitting Types Theorem for first order logic with infinitary relation symbols
Authors: Ahmed Tarek Sayed , Samir Basim 
Published: September 2007

AbstractIn this paper, an extension of first order logic is introduced. In such logics atomic formulas may have infinite lengths. An Omitting Types Theorem is proved. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Two cardinal models for singular μ
Authors: Garti Shimon , Shelah Saharon 
Published: September 2007

AbstractWe deal here with colorings of the pair (μ+, μ), when μ is a strong limit and singular cardinal. We show that there exists a coloring c with no refinement. It follows that the properties of colorings of (μ+, μ) when μ is singular differ in an essential way from the case of regular μ (although the identities may be the same). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On witnessed models in fuzzy logic II
Authors: Hájek Petr 
Published: September 2007

AbstractFirst the expansion of the Łukasiewicz (propositional and predicate) logic by the unary connectives of dividing by any natural number (Rational Łukasiewicz logic) is studied; it is shown that in the predicate case the expansion is conservative w.r.t. witnessed standard 1‐tautologies. This result is used to prove that the set of witnessed standard 1‐tautologies of the predicate product logic is Π2‐hard. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Corrigendum to “Generalized periodicity and primitivity for words”
Authors: Ito Masami , Lischke Gerhard 
Published: September 2007

AbstractWe correct a mistake in the paper “Generalized periodicity and primitivity for words” [4] and justify the existence of regular languages all of whose roots are not even context‐sensitive. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Large‐Scale Production of Homogeneous Helical Amylose/SWNTs Complexes with Good Biocompatibility
Authors: Fu Chuanlong , Meng Lingjie , Lu Qinghua , Zhang Xiaoke , Gao Chao 
Published: September 2007

AbstractThe key to developing novel applications of SWNTs in biotechnology and biomedicine is to improve their biocompatibility and solubility in water and to assemble them into useful architectures. We describe how amylose can help to solubilize SWNTs and wrap around SWNTs into helical superstructures with periodic pitch. FT‐IR, Raman spectroscopy, 1H NMR and HR‐TEM are used to confirm the generation of amylose/SWNTs complexes (A/S‐C). It is demonstrated that most of the A/S‐C have similar diameters (ca. 20–30 nm) and a helical morphology with a pitch of ca. 14 nm. A test of Hela cell viability revealed that the A/S‐C had much better biocompatibility than SWNTs.magnified image
Critical exponent for non‐Newtonian filtration equation with homogeneous Neumann boundary data
Authors: Wang Zejia , Yin Jingxue , Wang Lusheng 
Published: September 2007

AbstractThis paper is concerned with large time behavior of solutions to the homogeneous Neumann problem of the non‐Newtonian filtration equation. It is shown that the critical Fujita exponent for the problem considered is determined not only by the spatial dimension and the nonlinearity exponent, but also by the coefficient k of the first‐order term. In fact, we show that there exist two thresholds k∞ and k1 on the coefficient k of the first‐order term, and the critical Fujita exponent is a finite number when k is between k∞ and k1, while the critical exponent does not exist when k⩽k∞ or k⩾k1. Copyright © 2007 John Wiley & Sons, Ltd.
Substituent effects on 15N and 13C NMR chemical shifts of 5‐phenyl‐1,3,4‐oxathiazol‐2‐ones: a theoretical and spectroscopic study
Authors: Markgraf J. Hodge , Hong Lu , Richardson David P. , Schofield Mark H. 
Published: September 2007

AbstractThe synthesis and assignment of 15N and 13C NMR signals of the 1,3,4‐oxathiazol‐2‐one ring in a series of para‐substituted 5‐phenyl derivatives are reported. DFT calculations of 15N and 13C chemical shifts correspond closely to observed values. Substituent effects are interpreted in terms of the Hammett correlation and calculated bond orders. Copyright © 2007 John Wiley & Sons, Ltd.
Analyzing equilibrium water exchange between myocardial tissue compartments using dynamical two‐dimensional correlation experiments combined with manganese‐enhanced relaxography
Authors: Seland John Georg , Bruvold Morten , Brurok Heidi , Jynge Per , Krane Jostein 
Published: September 2007

AbstractWater compartments were identified and equilibrium water exchange was studied in excised rat myocardium enriched with intracellular manganese (Mn2+). Standard relaxographic measurements were supplemented with diffusion‐T2 and T1‐T2 correlation measurements. In nonenriched myocardium, one T1 component (800 ms) and three T2 components (32, 120, and 350 ms) were identified. The correlation measurements revealed fast‐ and slow‐diffusing water fractions with mean diffusion coefficients of 1.2 × 10−5 and 3.0 × 10−5 cm2 s−1. The two shortest T2 components, which had different diffusivities, both originated from water in intracellular compartments. A component with longer relaxation time (T1 ≈ 2200 ms; T2 ≈ 1200 ms), originating from extra‐tissue water, was also observed. The presence of this component may lead to erroneous estimations of water exchange rates from multiexponential relaxographic analyses of excised tissues. The tissue T1 value is strongly reduced with increasing enrichment of Mn2+, and eventually a second tissue T1 component emerges, indicating a shift in the equilibrium water exchange between intra‐ and extracellular compartments from the fast‐exchange limit to the slow‐exchange regime. Using a two‐site water exchange analysis, the lifetime of intracellular water, Tic, was found to be 475 ms, with a fraction, pic, of 0.71. Magn Reson Med 58:674–686, 2007. © 2007 Wiley‐Liss, Inc.