bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcriptional Analysis of Soybean Root Response to Fusarium virguliforme, the Causal Agent of Sudden Death Syndrome
Authors: Radwan Osman , Liu Yu , Clough Steven J.
Published: July 2011

Sudden death syndrome (SDS) of soybean can be caused by any of four distinct Fusarium species, with F. virguliforme and F. tucumaniae being the main casual agents in North and South America, respectively. Although the fungal tissue is largely confined to the roots, the fungus releases a toxin that is translocated to leaf tissues, in which it causes interveinal chlorosis and necrosis leading to scorching symptoms and possible defoliation. In this study, we report on an Affymetrix analysis measuring transcript abundances in resistant (PI 567.374) and susceptible (Essex) roots upon infection by F. virguliforme, 5 and 7 days postinoculation. Many of the genes with increased expression were common between resistant and susceptible plants (including genes related to programmed cell death, the phenylpropanoid pathway, defense, signal transduction, and transcription factors), but some genotype-specific expression was noted. Changes in small (sm)RNA levels between inoculated and mock-treated samples were also studied and implicate a role for these molecules in this interaction. In total, 2,467 genes were significantly changing in the experiment, with 1,694 changing in response to the pathogen; 93 smRNA and 42 microRNA that have putative soybean gene targets were identified from infected tissue. Comparing genotypes, 247 genes were uniquely modulating in the resistant host, whereas 378 genes were uniquely modulating in the susceptible host. Comparing locations of differentially expressed genes to known resistant quantitative trait loci as well as identifying smRNA that increased while their putative targets decreased (or vice versa) allowed for the narrowing of candidate SDS defense-associated genes.
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

PNAG 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

Hydrogen (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.
Transient Heat Exchanger Response With Pressure Regulated Outflow
Authors: Regulagadda P. , Naterer G. F. , Dincer I.
Published: July 2011

This paper analyzes the thermal performance of a co-current flow heat exchanger with transient gas outflow. The temperature distributions of the working fluid, heating fluid, and the wall over the length of the heat exchanger are predicted by an integral formulation. The heat transfer rates are determined at various stages of the heat exchanger operation. An integral formulation of the nondimensionalized governing equations is solved numerically, using a time-marching algorithm. The temperature distributions of the working fluid and the wall have an exponential increase from the inlet to the outlet of the heat exchanger. The heating fluid shows an initial decrease and subsequent increase of temperature. A base model for the step change in the mass flow of the working fluid is developed and compared against past data for purposes of validation. In addition, results are presented and discussed for the time-varying performance, during pressure regulated gas outflow from the heat exchanger.
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.
BI-DIRECTIONAL PEDESTRIANS WITH A PARTITION LINE
Authors: YANG LING-XIAO , ZHAO XIAO-MEI , ZHENG JIAN-FENG
Published: July 2011

By introducing a partition line into the walking strategies of the bi-directional pedestrian model recently proposed by Baek et al. [S. K. Baek, P. Minnhagen, S. Bernhardsson, K. Choi, B. J. Kim, Phys. Rev. E80, 016111 (2009)], we propose three walking strategies when pedestrians are moving outside the partition line, and carry out numerical simulations. The results show the proposed walking strategies have a significant impact on pedestrians' average walking velocity, pedestrians' distribution and road utilization.
DIRECT NUMERICAL SIMULATION OF DETACHMENT OF SINGLE CAPTURED LEUKOCYTE UNDER DIFFERENT FLOW CONDITIONS
Authors: LUO Z. Y. , XU F. , LU T. J. , BAI B. F.
Published: July 2011

Antibody-based cell isolation using microfluidics finds widespread applications in disease diagnostics and treatment monitoring at point of care (POC) for global health. However, the lack of knowledge on underlying mechanisms of cell capture greatly limits their developments. To address this, in this study, we developed a mathematical model using a direct numerical simulation for the detachment of single leukocyte captured on a functionalized surface in a rectangular microchannel under different flow conditions. The captured leukocyte was modeled as a simple liquid drop and its deformation was tracked using a level set method. The kinetic adhesion model was used to calculate the adhesion force and analyze the detachment of single captured leukocyte. The results demonstrate that the detachment of single captured leukocyte was dependent on both the magnitude of flow rate and flow acceleration, while the latter provides more significant effects. Pressure gradient was found to represent as another critical factor promoting leukocyte detachment besides shear stress. Cytoplasmic viscosity plays a much more important role in the deformation and detachment of captured leukocyte than cortex tension. Besides, better deformability (represented as lower cytoplasmic viscosity) noteworthy accelerates leukocyte detachment. The model presented here provides an enabling tool to clarify the interaction of target cells with functional surface and could help for developing more effective POC devices for global health.
BACTERIAL CELLULOSE: A NATURAL NANOMATERIAL FOR BIOMEDICAL APPLICATIONS
Authors: WANG JUNPING , ZHU YIZHOU , DU JIAN
Published: July 2011

Bacterial cellulose (BC) synthesized from Acetobacter xylinum has drawn lots of attention and interest from biomedical device field due to its unique structure and properties. Characterized by its remarkable physical strength and extremely hydrophilic surface, BC has become a favorable material for wound healing, neuron protection, and vascular grafts. Moreover, due to its homologous structure with native extracellular matrix, BC nanofibrous matrix could also be a potent candidate for tissue-engineered scaffolding materials. In this review, the characters and properties of BC, as a promising material for regenerative medicine, are summarized. The progresses made on application of BC to wound dressing, vascular grafts, meniscus and cartilage repair, bone healing, and other biomedical fields are expatiated in details. In the end, the future expectation of BC is briefly discussed. Overall, this low cost, biocompatible, and versatile nanomaterial could eventually be developed as an excellent platform for a new generation of medical device and regenerative medicine.
Utility of the Fluid-Attenuated Inversion Recovery Sequence in Detecting a Hyperintense Putaminal Rim in Multiple System Atrophy-Parkinsonism: A Preliminary Study
Authors: Sakurai Keita , Yamawaki Takemori , Okita Kenji , Kato Daisuke , Matsukawa Noriyuki , Kawaguchi Takatsune , Kobayashi Susumu , Nagai Keiichi , Muto Masahiro , Hosono Akihiro , Shibamoto Yuta
Published: July 2011

Objective: To investigate the utility of fluid-attenuated inversion recovery (FLAIR) imaging for diagnosing multiple system atrophy-parkinsonism (MSA-P). Methods: We retrospectively evaluated 49 subjects (19 with MSA-P including 11 with early-stage disease, 15 with Parkinson’s disease and 15 matched controls) in order to compare the diagnostic value of FLAIR imaging to detect a hyperintense putaminal rim (HPR) with that of T2-weighted (T2W) imaging. Results: Compared with T2W imaging, FLAIR imaging detected HPR more conspicuously in the 19 MSA-P patients (p = 0.01); this trend was also observed in 11 early-stage MSA-P patients (p = 0.01). Furthermore, FLAIR imaging tended to increase sensitivity of detecting HPR compared with T2W imaging (all patients: 89 vs. 58%, p = 0.07; early-stage patients: 100 vs. 55%, p = 0.06). Conclusions: FLAIR imaging might be more useful for detecting HPR in MSA-P patients, even though they are at an early stage.
Adherence in the Treatment of Psoriasis: A Systematic Review
Authors: Augustin M. , Holland B. , Dartsch D. , Langenbruch A. , Radtke M.A.
Published: July 2011

Background: Medication adherence and compliance are essential for disease management and can significantly improve outcomes and quality of patient care. The literature suggests that up to 40% of patients do not use their medication as intended. Objective: To elucidate current knowledge on adherence/compliance in psoriasis. In particular, methods of adherence/compliance evaluation and influencing factors were to be identified. Methods: Systematic literature review based on a protocol-rooted search in online databases, followed by a structured critical appraisal and consecutive descriptive report. Results: Thirty-five original publications on adherence/compliance in psoriasis were identified, addressing the extent and quality of adherence/compliance in topical, systemic and UV treatments. Estimates of compliance varied considerably between 27 and 97%. Age, sex, psychosocial, disease-specific and treatment-specific factors were identified as predictors of adherence/compliance. Conclusion: A better understanding of the determinants of adherence can improve the outcomes of psoriasis treatment and lead to higher patient satisfaction and quality of care.
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

Small 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

The 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.
RET/PTC rearrangement in benign and malignant thyroid diseases: a clinical standpoint
Authors: Marotta Vincenzo , Guerra Anna , Sapio Maria Rosaria , Vitale Mario
Published: July 2011

Cytological examination of fine needle aspiration biopsy is the primary means for distinguishing benign from malignant nodules. However, as inconclusive cytology is very frequent, the introduction of molecular markers in the preoperative diagnosis of thyroid nodules has been proposed in recent years. In this article, we review the clinical implications of preoperative detection of rearrangements of theRETgene (RET/papillary thyroid carcinoma (PTC)) in thyroid nodules. The prevalence ofRET/PTCin PTC depends on the histological subtypes, geographical factors, radiation exposure, and detection method. Initially,RET/PTCwas considered an exclusive PTC hallmark and later it was also found sporadically in benign thyroid lesions. More recently, the very sensitive detection methods, interphase fluorescencein situhybridization (FISH) and Southern blot on RT-PCR amplicons, demonstrated that the oligoclonal occurrence ofRETrearrangement in benign thyroid lesions is not a rare event and suggested that it could be associated with a faster enlargement in benign nodules. For this reason,RET/PTCcannot be considered as an absolute marker of PTC, and its diagnostic application must be limited to assays able to distinguish between clonal and oligoclonal expression. Detection ofRET/PTCby quantitative assays will be useful for diagnostic purposes in cytology specimens when a precise cutoff will be fixed in a clinical setting. Until that time, less sensitiveRET/PTCdetection methods and FISH analysis remain the most appropriate means to refine inconclusive cytology. Future studies with a long follow-up will further clarify the clinical significance of low level ofRETrearrangements in benign nodules.
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.
The Effects of Guided Imagery on Affect, Cognition, and Pain in Older Adults in Residential Care: A Randomized Controlled Study from Thailand
Authors: Elsegood Kelly J. , Wongpakaran Nahathai
Published: July 2011

Few studies have examined the effects of guided imagery on older adults in residential care. This study aimed to evaluate the outcome of group-delivered guided imagery over a 16-day period with a sample of Thai older adults in residential care (
N
= 31). Residents were randomly allocated to the guided imagery treatment group or usual care control group. No significant differences were found between the two groups regarding affective states, cognitive functioning, or pain. The results are discussed in relation to a ceiling effect and other methodological factors that may have contributed to the lack of positive outcomes. As the evidence base remains inconclusive, it is hoped that future studies will seek to establish the effects of using guided imagery with older adults in residential care.
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

This 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

The 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.
Signal transduction pathways through cytoprotective, apoptotic and hypertrophic stimuli: a comparative study in adult cardiac myocytes
Authors: Markou Thomais , Barlaka Eleftheria , Bartucci Monica , Lazou Antigone
Published: July 2011

In response to pathophysiological stresses, cardiac myocytes undergo hypertrophic growth or apoptosis. Multiple signalling pathways have been implicated in these responses and among them, kinases such as mitogen‐activated protein kinases (MAPKs) and Akt. However, the distinction between signalling pathways originally believed to be specific for either hypertrophy, apoptosis or cell survival is fading. The existing data, coming from different experimental systems, often are conflicting. In this study, we sought to compare aspects of intracellular signalling activated by diverse stimuli in a single experimental system, adult rat cardiac myocytes. Furthermore, we assessed the role of these stimuli in eliciting a particular cell phenotype, i.e. whether they promote hypertrophy, cell survival or apoptosis. The results demonstrate that the hypertrophic agonist phenylephrine is the most potent activator of MAPKs/mitogen and stress‐ activated kinase MSK1, although its effect on Akt phosphorylation is relatively minor. The pro‐apoptotic concentration of H2O2activates strongly both MAPKs and PI3K/Akt pathways. Insulin‐like growth factor‐1 has a minimal effect on phosphorylation of MAPKs/MSK1, but it is a potent activator of Akt. In conclusion, hypertrophic, pro‐survival or apoptotic stimuli operate through the same signalling pathways with different time course and amplitude of kinase activation. Thus, to determine the effect of different stimuli on cell fate, it is important to assess signalling pathways as a network and not as a single pathway. Copyright © 2011 John Wiley & Sons, Ltd.
Color separation for colored fiber blends based on the fuzzy C‐means cluster
Authors: Lu Yuzheng , Gao Weidong , Liu Jihong
Published: July 2011

Colored 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

[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

It 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

We 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.

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Relationship between values and trends of two circulation indices and temperature and rainfall in Argentina
Authors: Alessandro Adelia P.
Published: July 2011

Extreme 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

The 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.
Modeling subject‐specific phase‐dependent effects and variations in longitudinal responses via a geometric Brownian motion process
Authors: Zhu Li , Hsieh Fushing , Li Juan , Chi Eric
Published: July 2011

We address statistical issues regarding modeling a collection of longitudinal response trajectories characterized by the presence of subject‐specific phase‐dependent effects and variation. To accommodate these two time‐varying individual characteristics, we employ a geometric stochastic differential equation for modeling based on a Brownian motion process and develop a two‐step paradigm for statistical analysis. This paradigm reverses the order of statistical inference in random effects model. We first extract individual information about phase‐dependent treatment effects and volatility parameters for all subjects. Then, we derive the association relationship between the parameters characterizing the individual longitudinal trajectories and the corresponding covariates by means of multiple regression analysis. The stochastic differential equation model and the two‐step paradigm together provide significant advantages both in modeling flexibility and in computational efficiency. The modeling flexibility is due to the easy adaptation of temporal change points for subject‐specific phase transition in treatment effects, whereas the computational efficiency benefits in part from the independent increment property of Brownian motion that avoids high‐dimensional integration. We demonstrate our modeling approach and statistical analysis on a real data set of longitudinal measurements of disease activity scores from a rheumatoid arthritis study. 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

Existence 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.
Fitting classes of CC-groups
Authors: Dixon Martyn R.
Published: July 2011

The theory of Fitting classes is, by now, a well established part of the theory of finite soluble groups. In contrast, Fitting classes have received rather scant attention in infinite groups, although some recent work of Beidleman and Karbe [2] and Beidleman, Karbe and Tomkinson [3] suggest that one can obtain results in this direction. The paper [2], cited above, in fact generalizes earlier work of Tomkinson [9] to the class of locally soluble FC-groups. The present paper is concerned with the theory of Fitting classes in a class of groups somewhat similar to the class of FC-groups, namely the class of CC-groups, introduced by Polovickiǐ in [6]. A group G is a CC-group if G/CG(xG) is a Černikov group for all x ∈ G where, as in the rest of this paper, we use the standard group theoretic notation of [7]. Recently, Alcázar and Otal [1] have shown how to generalize results of B. H. Neumann [5] to the class of CC-groups. The main purpose of the present note is to illustrate further how one can handle CC-groups, in an analogous manner to FC-groups, by using techniques similar to those used in [1] and [4].
Schematherapie für Cluster-C-Persönlichkeitsstörungen
Authors: Arntz Arnoud
Published: July 2011

Zusammenfassung Cluster-C-Persönlichkeitsstörungen (PS) stellen eine therapeutische Herausforderung dar. In dieser Arbeit wird ein neuer schematherapeutischer Ansatz für die Behandlung von Cluster-C-PS vorgestellt. Zunächst wird ein Überblick über die Schema-Modus-Modelle der 3 Cluster-C PS sowie über die Formulierung individueller Fallkonzepte gegeben. Die wichtigsten Überlebensstrategien jeder Störung (Vermeidung, Kontrolle, Dependenz) spiegeln sich in den jeweiligen Coping-Modi; daneben finden auch biografische Faktoren Eingang über Kindmodi und internalisierte Elternmodi. Zudem werden die zentralen schematherapeutischen Interventionen und der Umgang mit typischen klinischen Problemen bei diesen Patientengruppen diskutiert. Erste Studienergebnisse zeigen eine gute Anwendbarkeit des Ansatzes.
The influence of a temperature dependent bandgap on the energy scale of modulated photocurrent experiments
Authors: Luckas Jennifer , Kremers Stephan , Krebs Daniel , Salinga Martin , Wuttig Matthias , Longeaud Christophe
Published: July 2011

Amorphous semiconductors and chalcogenide glasses exhibit a high density of localized states in their bandgap as a consequence of structural defects or due to a lack of long range order. These defect states have a strong influence on the electronic transport properties. Thus, many theories attribute the “resistance drift” or the “threshold switching” effects, both observed in amorphous phase change alloys, to defects within the bandgap. The energetic distribution of states within the bandgap can be probed via modulated photocurrent (MPC) experiments that enable a spectroscopy of the relative density of these defect states by varying the modulation frequency at various temperatures T. It is also a common feature that the bandgap decreases with temperature. Nevertheless, the consequences of a shrinking bandgap with increasing temperature have been neglected in the classical analysis of MPC experiments. In this paper, we propose to add correction terms to the classical MPC energy scaling to take the temperature dependence of the bandgap of the studied material into account to improve the accuracy of the determination of the defect distribution. We illustrate the efficacy of our proposed corrections by applying it to the study of disordered materials such as hydrogenated amorphous silicon a-Si:H, a-GeTe and a-Ge2Sb2Te5.
Ripple dislocation slip in wrinkled gold film deposited on polydimethylsiloxane
Authors: Lin C. B. , Chuang Y. F. , Liu Y. H. , Lee Sanboh , Chou Y. T.
Published: July 2011

The motion of ripple dislocations in a wrinkled thin film of gold deposited on polydimethylsiloxane (PDMS) was investigated. The deposition was made under tensile load along the first direction on the PDMS plate. After the tensile load was released, a ripple pattern and ripple dislocations were formed on the surface. Upon reloading in the second direction, these ripple dislocations were able to slip. At a given tensile load, the speed of slip decreased as the loading time increased, and finally reached a constant value, which was increasing with the applied load. The measured data were interpreted with a dynamic model based on Newton’s law of motion. Interaction of ripple dislocations was also observed. It was shown that a pair of positive and negative ripple dislocations of equal strength could annihilate each other or form a dipole, depending on the magnitude of the applied load.
There's no accounting for taste: bait attractants and infrared digital cameras for detecting small to medium ground-dwelling mammals
Authors: Paull David J. , Claridge Andrew W. , Barry Simon C.
Published: July 2011

Context Reliable information about the occurrence and distribution of threatened forest-dwelling mammals is critical for developing effective conservation plans. To optimise limited resources, advances need to be made to the toolkit available for detecting rare and cryptic fauna. Aims We trialled three bait attractants (peanut butter with oats, live mealworms and black truffle oil) in combination with infrared digital cameras to determine whether detection rates of forest-dwelling native mammals in south-eastern Australia were influenced by: (1) bait type; (2) previous visits by conspecifics; (3) previous visits by Rattus; and (4) duration of bait deployment. Methods Bait attractants were set at 40 camera stations in combination with odourless controls. Over two fortnight-long deployments, 1327 images were captured of 22 mammal and bird species. From these data, detailed statistical analyses were conducted of six mammal genera. Key results Peanut butter with oats was found to be a significantly better attractant than empty bait holders for Antechinus, Isoodon, Perameles and Rattus, but not for Potorous or Pseudocheirus. Truffle oil and mealworms were also significantly better attractants than the control for Rattus but not the other five genera. When Antechinus, Isoodon, Potorous or Rattus were detected at a bait station there was a significant likelihood they had been detected there during the previous 24 h. This was not the case for Perameles or Pseudocheirus. A prior visit by Rattus to a station had no significant influence on the detection probabilities of Antechinus, Isoodon, Perameles, Potorous and Pseudocheirus during the subsequent 24 h. Detection probabilities for Isoodon and Rattus declined significantly during the fortnight-long deployments but trends for the other genera were not significant. Conclusions Peanut butter with oats is an excellent general purpose bait for detecting small to medium-sized mammals. However, scope exists for using other baits to target species. For example, truffle oil baits may reduce by-catch of non-target Rattus in labour intensive cage trapping of bandicoots. Regardless of bait type, longer deployments are necessary to detect Perameles, Potorous or Pseudocheirus than Antechinus, Isoodon or Rattus. Implications Targeted detection of predominantly ground-dwelling mammals may be improved by better understanding the attraction of species to baits and required bait deployment times.
Dissociation Dynamics of Nitrous Oxide from Jet-cooling Absorption Spectrum in 142.5–147.5 nm
Authors: Zhen Cheng , Hu Ya-hua , Zhou Xiao-guo , Liu Shi-lin
Published: July 2011

The absorption spectrum of the C1II state of N2O molecule in the wavelength range of 142.5–147.5 nm has been measured under the jet-cooled condition, and the clear spectral features are displayed. A vibrational progression is observed with a frequency interval of about 500 cm−1. With the aid of potential energy surfaces (PES) of the low-lying electronic states of N2O, the vibrational progression is assigned as the bending mode of the repulsive C1II state. From the Fourier transformation analysis, the recurrence period of the periodic orbit near the transition state region is derived to be 65 fs. Through the least-square Lorentzian fitting, the lifetimes of the resonance levels are estimated from their profile widths to be about 20 fs, which is shorter than the recurrence period. Therefore, a new explanation is suggested for the observed diffuse spectral structure, based on the behavior of dissociating N2O on PES of the C1II state in the present excitation energy range.
Dissociation Pathway Analysis of Thymine under Low Energy VUV Photon Excitation
Authors: Li Shao-bo , Guo Hui-jun , Zhang Li-dong , Qi Fei
Published: July 2011

Photon-induced dissociation pathways of thymine are investigated with vacuum ultraviolet photoionization mass spectrometry and theoretical calculations. The photoionization mass spectra of thymine at different photon energy are measured and presented. By selecting suitable photon energy exclusively molecular ion m/z = 126 is obtained. At photon energy of 12.0 eV, the major ionic fragments at m/z = 98, 97, 84, 83, 70, and 55 are obtained, which are assigned to C4H6N2O+, C4H5N2O+, C3H4N2O+ (or C4H6NO+), C4H5NO+, C2NO2+, and C3H5N+, respectively. With help of theoretical calculations, the detailed dissociation pathways of thymine at low energy are well established.