bluuebunny/crossref_metadata_2025_split huggingface dataset:
2011 German Escherichia coli outbreak: Prophage analysis of close-assembled TY2482 against 55989 using PHAST
Authors: Cheung Man Kit , LI Lei , Nong Wenyan , Kwan Hoi Shan 
Published: July 2011

AbstractUsing the Hiseq data of the German E. coli outbreak isolate TY2482, preliminary prophage analyses have been performed by some researchers previously. With the closed assembly of the same isolate being available, another round of analysis might help in resolving questions that remain unclear due to the incompleteness of the dataset.
Modulation of poly‐N‐acetylglucosamine accumulation within mature Staphylococcus epidermidis biofilms grown in excess glucose
Authors: Cerca Filipe , França Ângela , Guimarães Rodrigo , Hinzmann Mariana , Cerca Nuno , Lobo da Cunha Alexandre , Azeredo Joana , Vilanova Manuel 
Published: July 2011

ABSTRACTPNAG is a major component of Staphylococcus epidermidis biofilms involved in intercellular adhesion as well as in the interaction of the biofilm with components of the host immune response. Synthesis of PNAG has been found to be regulated by several environmental factors. In the present study, the effect of glucose metabolism‐dependent culture medium acidification in PNAG accumulation was evaluated. Established S. epidermidis biofilms were allowed to grow in excess glucose with or without maintained pH conditions. PNAG accumulation in these biofilms was determined by flow cytometry and fluorescence microscopy using wheat germ agglutinin as a fluorescent probe. Biofilms grown in maintained pH conditions presented significantly higher amounts of this polymer as well as higher icaA expression than biofilms grown in acidic pH conditions. Moreover, PNAG accumulation in biofilms grown in non‐maintained pH conditions occurred in association with cell death. Overall, we show that glucose metabolism by decreasing the culture pH affects biofilm physiology in respect to PNAG production and cell death. The reported in vitro modulation of PNAG accumulation within S. epidermidis biofilms further highlights the role of environment on determining the biofilm physiological state.
Deletion of alternative pathways for reductant recycling in Thermococcus kodakarensis increases hydrogen production
Authors: Santangelo Thomas J. , Čuboňová L'ubomíra , Reeve John N. 
Published: July 2011

SummaryHydrogen (H2) production by Thermococcus kodakarensis compares very favourably with the levels reported for the most productive algal, fungal and bacterial systems. T. kodakarensis can also consume H2 and is predicted to use several alternative pathways to recycle reduced cofactors, some of which may compete with H2 production for reductant disposal. To explore the reductant flux and possible competition for H2 production in vivo, T. kodakarensis TS517 was mutated to precisely delete each of the alternative pathways of reductant disposal, H2 production and consumption. The results obtained establish that H2 is generated predominantly by the membrane‐bound hydrogenase complex (Mbh), confirm the essential role of the SurR (TK1086p) regulator in vivo, delineate the roles of sulfur (S°) regulon proteins and demonstrate that preventing H2 consumption results in a substantial net increase in H2 production. Constitutive expression of TK1086 (surR) from a replicative plasmid restored the ability of T. kodakarensis TS1101 (ΔTK1086) to grow in the absence of S° and stimulated H2 production, revealing a second mechanism to increase H2 production. Transformation of T. kodakarensis TS1101 with plasmids that express SurR variants constructed to direct the constitutive synthesis of the Mbh complex and prevent expression of the S° regulon was only possible in the absence of S° and, under these conditions, the transformants exhibited wild‐type growth and H2 production. With S° present, they grew slower but synthesized more H2 per unit biomass than T. kodakarensis TS517.
Glycine cleavage enzyme complex: Molecular cloning and expression of the H-protein cDNA from cultured human skin fibroblasts
Authors: Zay Agnes , Choy Francis Y.M. , Patrick Chelsea , Sinclair Graham 
Published: July 2011

The human H-protein is one of four essential components (H-, L-, P-, and T-proteins) of the mammalian glycine cleavage enzyme complex and its function is involved in the pathogenesis and diagnosis of glycine encephalopathy. A transcript corresponding to the glycine cleavage H-protein functional gene was isolated from cultured human skin fibroblasts along with a transcript for a putative processed pseudogene on chromosome 2q33.3. Sequence analysis of the fibroblast H-protein functional gene transcript showed complete identity to that reported from human liver. The H-protein cDNA was subsequently cloned with a hexahistidine affinity tag in the Pichia pastoris plasmid vector pPICZαA and recombined into the yeast genome downstream of the alcohol oxidase promoter for methanol-induced expression. The recombinant H-protein was secreted into the culture medium and purified to homogeneity using a one-step nickel-nitrilotriacetic acid resin column. Approximately 4 mg of homogeneous H-protein was obtained from 1 L of culture medium. Since the attachment of a lipoic acid prosthetic group is required for H-protein function, we have expressed and purified E. coli lipoate protein ligase and succeeded in lipoylating H-protein, converting the apo-H-protein to the functional holo-H-protein. A lipoamide dehydrogenase assay was performed to confirm that the apo-H-protein was inactive, whereas the holo-H-protein was approximately 2.3-fold more active than free lipoic acid as a hydrogen donor in driving the reaction. The availability of copious amounts of human recombinant H-protein by using Pichia pastoris expression and affinity purification will facilitate the elucidation of the structure and function of the H-protein and its relationship to the P-, T-, and L-proteins in the glycine cleavage enzyme complex. In view of the fact that there is no detectable glycine cleavage enzyme activity in human skin fibroblasts, we speculate that a plausible function of the H-protein is to interact with the L-protein, which is also part of the l-ketoglutarate dehydrogenase complex present in fibroblasts.
The kinematic consequences of locomotion on sloped arboreal substrates in a generalized (Rattus norvegicus) and a specialized (Sciurus vulgaris) rodent
Authors: Schmidt André , Fischer Martin S. 
Published: July 2011

SUMMARYSmall mammals must negotiate terrains that consist of numerous substrates that vary in diameter, surface structure, rigidity and orientation. Most studies on mammals have focused on the effects of substrate diameter during horizontal locomotion, especially in small- to medium-sized primates and marsupials. Locomotion across sloped arboreal substrates, however, is poorly understood. Here, in order to determine which locomotor parameters a terrestrial mammal, the rat, and a tree-dwelling mammal, the European red squirrel, modify in response to differences in substrate orientation, three-dimensional kinematics were examined using biplanar videoradiography as the animals moved on 30 and 60 deg inclined branches. Our results revealed that to maintain stability and friction as well as balance during inclined branch locomotion, these species utilize comparable locomotor adjustments despite significant differences in travel speed and gait. Rats and European red squirrels increased limb flexion and retraction in order to bring the center of mass as close as possible to the substrate surface and to achieve maximum propulsion. Additionally, forelimbs were placed more laterally and underneath the branch whereas the hindlimbs were placed approximately on the top of the branch. These locomotor adjustments, which have also been observed in primates and marsupials, are independent of speed, morphological adaptations and limb proportions and thus might be strategies used by early mammals. Our results also suggest that mammals that lack, or have reduced, grasping abilities try to maintain the locomotor mode used during horizontal branch locomotion on inclined branches for as long as possible.
Intrinsic neuronal excitability: implications for health and disease
Authors: Wijesinghe Rajiv , Camp Aaron J. 
Published: July 2011

AbstractThe output of a single neuron depends on both synaptic connectivity and intrinsic membrane properties. Changes in both synaptic and intrinsic membrane properties have been observed during homeostatic processes (e.g., vestibular compensation) as well as in several central nervous system (CNS) disorders. Although changes in synaptic properties have been extensively studied, particularly with regard to learning and memory, the contribution of intrinsic membrane properties to either physiological or pathological processes is much less clear. Recent research, however, has shown that alterations in the number, location or properties of voltage- and ligand-gated ion channels can underlie both normal and abnormal physiology, and that these changes arise via a diverse suite of molecular substrates. The literature reviewed here shows that changes in intrinsic neuronal excitability (presumably in concert with synaptic plasticity) can fundamentally modify the output of neurons, and that these modifications can subserve both homeostatic mechanisms and the pathogenesis of CNS disorders including epilepsy, migraine, and chronic pain.
Engaging Learners in Cooperative Learning Through Environmental and Cross-Cultural Activities
Authors: Mitakidou Soula , Tamoutseli Konstantia 
Published: July 2011

Engaging Learners in Cooperative Learning Through Environmental and Cross-Cultural Activities
There is a definite intersection of targets and intentions between education for sustainable development (ESD) and cross-cultural education (CCE), since both ESD and CCE aspire to pursue and develop values such as equity, democracy and quality of life in a multicultural setting. Apart from their common philosophical basis, ESD and CCE endorse similar teaching methods, i.e. experiential and cooperative learning, and pursue the development of abilities such as research interest, critical thought and political awareness, with the intention to develop a learning community intrinsically connected with the wider community and society. This study aspires to explore the possibilities of cooperative learning to effectively promote the aims of both ESD and CCE. The children of a public school in Thessaloniki, Greece, were involved in this action research related to their local environment. The methodological tools used included walk mapping and landscape analysis charts combined with environmental assessment sheets. The ensuing discussion facilitates reflection on the prospects of cooperation in a class with a mixed ability population.
A two‐compartment bioreactor system made of commercial parts for bioprocess scale‐down studies: Impact of oscillations on Bacillus subtilis fed‐batch cultivations
Authors: Junne Stefan , Klingner Arne , Kabisch Johannes , Schweder Thomas , Neubauer Peter 
Published: July 2011

AbstractThis study describes an advanced version of a two‐compartment scale‐down bioreactor that simulates inhomogeneities present in large‐scale industrial bioreactors on the laboratory scale. The system is made of commercially available parts and is suitable for sterilization with steam. The scale‐down bioreactor consists of a usual stirred tank bioreactor (STR) and a plug flow reactor (PFR) equipped with static mixer modules. The PFR module with a working volume of 1.2 L is equipped with five sample ports, and pH and dissolved oxygen (DO) sensors. The concept was applied using the non‐sporulating Bacillus subtilis mutant strain AS3, characterized by a SpoIIGA gene knockout. In a fed‐batch process with a constant feed rate, it is found that oscillating substrate and DO concentration led to diminished glucose uptake, ethanol formation and an altered amino acid synthesis. Sampling at the PFR module allowed the detection of dynamics at different concentrations of intermediates, such as pyruvic acid, lactic acid and amino acids. Results indicate that the carbon flux at excess glucose and low DO concentrations is shifted towards ethanol formation. As a result, the reduced carbon flux entering the tricarboxylic acid cycle is not sufficient to support amino acid synthesis following the oxaloacetic acid branch point.
Binding and transport of PAMAM‐RGD in a tumor spheroid model: The effect of RGD targeting ligand density
Authors: Waite Carolyn L. , Roth Charles M. 
Published: July 2011

AbstractThe mechanisms governing the efficient tumor spheroid penetration and transport by poly(amidoamine) (PAMAM) dendrimers displaying varying numbers of cyclic RGD targeting peptides (2, 3, 7, or 10) were evaluated in this work. The cell‐free binding affinities and cellular internalization kinetics of PAMAM‐RGD conjugates to malignant glioma cells were determined experimentally, and the results were incorporated into a mathematical model to predict the transport of these materials through a multicellular tumor spheroid. The theoretical analysis demonstrated that greater RGD crosslinking may improve transport through tumor spheroids due to their decreased integrin‐binding affinity. This study provides evidence that altering the density of tumor‐targeting ligands from a drug delivery platform is a feasible way to optimize the tumor‐penetration efficiency of an anticancer agent, and provides insight into the physicochemical mechanisms governing the relative effectiveness of these conjugates. Biotechnol. Bioeng. 2011;108: 2999–3008. © 2011 Wiley Periodicals, Inc.
Color separation for colored fiber blends based on the fuzzy C‐means cluster
Authors: Lu Yuzheng , Gao Weidong , Liu Jihong 
Published: July 2011

AbstractColored fibers can be blended in a certain proportion to achieve a specific color. It is a very hard task for the colorist to find a good recipe to meet the final product without the aid of computer. In this article, a color separation method for the colored fiber blends is discussed to substitute for some manual work. The fuzzy C‐means cluster is a way to group the color in the colored fiber blends image. The distance index, which is a key factor during the fuzzy C‐means cluster process, is calculated in the RGB color space and the HSV color space with some transformation. The final experiment result proved that the colors of each pixel in the blends' image can be replaced by corresponding cluster center associating colors in the HSV color space, and the main texture as well as the main color information about the fibers in the image is	preserved. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2012
Structural Investigation of a Fully Ordered closo‐Ge92– Cluster in the Compound [K+(2,2,2‐crypt)]2Ge92–
Authors: Åkerstedt Josefin , Ponou Simeon , Kloo Lars , Lidin Sven 
Published: July 2011

Abstract[K+(2,2,2‐crypt)]2Ge92– containing the deltahedral Zintl anion Ge92– has been isolated from a solution of K4Ge9 in ethylenediamine in the presence of 2,2,2‐crypt, intended as an intermediate in mixed‐cluster synthesis. The subsequent crystallographic characterisation shows the closo‐Ge92– cluster unit to be tricapped trigonal‐prismatic with a symmetry very close to D3h. Each Ge92– unit is surrounded by two 2,2,2‐crypt units, each with a chelated K+ cation, viz. [K+(2,2,2‐crypt)]. The structure characterisation of this ordered Ge92– cluster is surprisingly enough the first one reported. A chemical bonding analysis reveals two local minima of D3h symmetry, with that of lowest energy being highly similar to that resulting from the crystallographic analysis of low‐temperature data. The cluster interaction scheme is based on highly delocalised bonding.
Strain accommodation in the zygomatic arch of the pig: A validation study using digital speckle pattern interferometry and finite element analysis
Authors: Bright Jen A. , Gröning Flora 
Published: July 2011

AbstractIt has been repeatedly suggested that mammalian cranial sutures act not only to allow growth but also to reduce the levels of strain experienced by the skull during feeding. However, because of the added complexity they introduce, sutures are rarely included in finite element (FE) models, despite their potential to influence strain results. Because sutures present different morphologies and with differing degrees of internal fusion, many different methods of modeling may be necessary to accurately measure strain environments. Alternatively, these variables may exert very little influence on the scale of a whole‐skull model. To validate suture modeling methods, four alternative ways of including a suture in 3D FE models of the pig zygomatic arch were considered and compared with ex vivo experimental data from digital speckle pattern interferometry (DSPI). The use of DSPI rather than traditional strain gauge techniques allows strain gradients around the suture as well as the motions of the two bones to be observed. Results show that the introduction of 3D elements assigned more compliant material properties than the surrounding bone, is the most effective way of modeling both morphologies of suture, both in tension and compression. However, models containing no suture are almost indistinguishable from these compliant suture models, beyond the high strain gradient immediately adjacent to the suture. Conversely, modeling the suture as an open break in the mesh, or with spring elements assigned suture properties, fails to reproduce the experiment. Thus, although a solid but flexible model of sutures is preferred, the similarity between these models and those without sutures tentatively suggests that such extra detail may be unnecessary in pigs if the behavior of the whole skull is of interest. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Bio‐electrosprayed Living Composite Matrix Implanted into Mouse Models
Authors: Jayasinghe Suwan N. , Warnes Gary , Scotton Chris J. 
Published: July 2011

AbstractWe show that composite de novo structures can be generated using bio‐electrosprays. Mouse lung fibroblasts are bio‐electrosprayed directly with a biopolymer to form cell‐bearing matrices, which are viable even when implanted subcutaneously into murine hosts. Generated cell‐bearing matrices are assessed in‐vitro and found to undergo all expected cellular behaviour. Subsequent in‐vivo studies demonstrate the implanted living matrices integrating as expected with the surrounding microenvironment. The in‐vitro and in‐vivo studies elucidate and validate the ability for either bio‐electrosprays or cell electrospinning to form a desired living architecture for undergoing investigation for repairing, replacing and rejuvenating damaged and/or ageing tissues.magnified image
Relationship between values and trends of two circulation indices and temperature and rainfall in Argentina
Authors: Alessandro Adelia P. 
Published: July 2011

AbstractExtreme values of two circulation indices are examined for the time series covering the period 1960–2006. The influence of circulation on surface temperature and rainfall in Argentina is analysed using a zonal index Z and a meridional index R at the 1000 and 500 hPa levels. Seasonal means for all the years representing extreme negative values of R(Z) at 1000 and/or 500 hPa, determine mainly positive (negative) temperature anomalies with increased rainfall in both indices. These characteristics revert for extreme positive values of R(Z). At 1000 hPa, seasonal anomaly trends of R are negative and significant. Trends of Z are all positive and significant, except for winter when they are not significant. Signs of trends at 500 hPa are the same as at 1000 hPa, except for Z in winter and R in summer, whose values are not significant. Annual and seasonal trends of the anomalies of Z differences between 500 and 1000 hPa, are mostly negative, which implies a decrease in baroclinicity in southernmost South America. Analysis of the statistical values obtained for both variables generated by extreme values of R and Z, and of the signs and significance of index trends at 1000 hPa indicates that both circulation indices might contribute to surface temperature warming during the last years of the period 1960/2006. The increase in R, whose influence is greater than that of Z, might contribute to greater rainfall. Copyright © 2011 Royal Meteorological Society
Comparing the Chronological Distribution of Enamel Hypoplasia in Rogowo, Poland (2nd century ad) Using Two Methods of Defect Timing Estimation
Authors: Krenz‐Niedbała M. , Kozłowski T. 
Published: July 2011

ABSTRACTThe frequency and chronological distribution of enamel hypoplasias were assessed in a Roman Period population of the Wielbark culture from Rogowo, northern Poland, dated to the 2nd century ad. Hypoplasias were recorded on permanent incisors, canines, and premolars of 52 skeletons. The position of linear defects on the crown surface was measured and then converted to the age of occurrence using two methods: a conventional method that employs the chart of enamel development for the permanent teeth, constructed by Massler et al. (1941) in Swärdstedt's (1966) modification, and the method by Goodman & Song (1999), which corrects for hidden cuspal enamel. Hypoplastic defects were found in 48.1% of examined cases. Linear defects [linear enamel hypoplasias (LEH)] were observed in 38.5% of individuals and in 22% of investigated teeth.The chronological distribution of LEH according to the conventional method revealed two peaks of defects: one at 2.6–3.0 years of age and the other at 4.1–4.5 years of age. The method that accounts for hidden cuspal enamel also provided two peaks, but they occurred at later ages: 3.0–4.0 and 4.6–5.0 years of age.The prevalence of hypoplasia in the Rogowo population in comparison with other European populations of the Roman Period seems to be rather low for both individuals and teeth affected. This may indicate advantageous living conditions, which are supported by archaeological data that suggest general well‐being of the Wielbark people. Copyright © 2011 John Wiley & Sons, Ltd.
Stainless Steel 2.0-mm Locking Compression Plate Osteosynthesis System for the Fixation of Comminuted Hand Fractures in Asian Adults
Authors: Hing-Cheong Wong , Hin-Keung Wong , Kam-Yiu Wong 
Published: July 2011

Objective The aim of this retrospective study was to analyse the clinical outcome of the application of stainless steel 2.0-mm locking compression plate (LCP) system for the treatment of comminuted hand fractures in Asian adults. Methods Six patients who had comminuted hand fractures were treated by open reduction and internal fixation with the application of stainless steel 2.0-mm LCP (AO Compact Hand System; Synthes, Oberdorf, Switzerland) from December 2009 to October 2010. The total arc of motion of fingers, grip power, complications, and additional surgery were recorded. Results Three out of six patients eventually restored good hand functions in terms of the total arc of finger motion (>220°) and grip power. The commonest complication was skin impingement in finger region by the implant (4 cases). Another common complication was restricted range of motion (3 cases). One patient had minimal degree of malrotation of his left little finger. Additional surgery was required in all the patients for implant removal (6 cases), tenolysis (3 cases), and capsulotomy (2 cases). Conclusions The stainless steel 2.0-mm LCP is useful for the fixation of unstable comminuted hand fractures, especially in metacarpal bones, because of its advantage of better stability, which allows more aggressive rehabilitation. However, its design is not very versatile and, therefore, limits its use in the finger region. Its bulkiness frequently causes implant impingement. The patients must be informed about the chance of implant removal later.
AN EXISTENCE RESULT OF ONE NONTRIVIAL SOLUTION FOR TWO POINT BOUNDARY VALUE PROBLEMS
Authors: BONANNO GABRIELE , SCIAMMETTA ANGELA 
Published: July 2011

AbstractExistence results of positive solutions for a two point boundary value problem are established. No asymptotic condition on the nonlinear term either at zero or at infinity is required. A classical result of Erbe and Wang is improved. The approach is based on variational methods.