bluuebunny/crossref_metadata_2025 huggingface dataset:
A full dimensional grid empowered simulation of the CO2 + CO2 processes
Authors: Bartolomei Massimiliano , Pirani Fernando , Laganà Antonio , Lombardi Andrea
Published: May 2012

A recently introduced bond–bond formulation of the intermolecular interaction has been extended to six‐atom systems to the end of assembling a new potential energy surface (PES) and has been incorporated into a grid empowered simulator able to handle the modeling of the CO2 + CO2 processes. The proposed PES is full dimensional and accounts for the dependence of the intermolecular interaction on some basic physical properties of the colliding partners, including modulations induced by the monomer deformation. The used analytical formulation of the interaction involves a limited number of parameters, each having a clear physical meaning. Guess values for these parameters can also be obtained from analytical correlation formulae. Such estimates can then be fine tuned by exploiting experimental and theoretical information. The resulting PES well describes stretched and bent asymptotic CO2 monomers as well as the CO2–CO2 interaction in the most and less stable configurations. On this potential massive quasiclassical elastic and inelastic detailed scattering trajectories have been integrated, by exploiting the innovative computational technologies of the grid. The efficiency of the approach used and the reliability of the estimates of the dynamical properties obtained in this way is such that we can now plan a systematic evaluation of the state specific rate coefficient matrix elements needed for space craft reentry modeling. Here, we present probabilities and cross sections useful to rationalize some typical mechanisms characterizing the vibrational transitions of the CO2 + CO2 system on the flexible monomer proposed PES. On such PES, the key dynamical outcomes are: (a) there is a strong energy interchange between symmetric stretching of the reactants and bending of the products (and viceversa) while asymmetric stretching is strongly adiabatic (b) reactant energy is more efficiently allocated (with respect to the rigid monomers PES) as product vibration when reactant stretching modes are excited while the contrary is true when the reactant bending mode is excited. © 2012 Wiley Periodicals, Inc.
Computational study of ligand binding in lipid transfer proteins: Structures, interfaces, and free energies of protein‐lipid complexes
Authors: Pacios Luis F. , Gómez‐Casado Cristina , Tordesillas Leticia , Palacín Arantxa , Sánchez‐Monge Rosa , Díaz‐Perales Araceli
Published: May 2012

Plant nonspecific lipid transfer proteins (nsLTPs) bind a wide variety of lipids, which allows them to perform disparate functions. Recent reports on their multifunctionality in plant growth processes have posed new questions on the versatile binding abilities of these proteins. The lack of binding specificity has been customarily explained in qualitative terms on the basis of a supposed structural flexibility and nonspecificity of hydrophobic protein‐ligand interactions. We present here a computational study of protein‐ligand complexes formed between five nsLTPs and seven lipids bound in two different ways in every receptor protein. After optimizing geometries in molecular dynamics calculations, we computed Poisson‐Boltzmann electrostatic potentials, solvation energies, properties of the protein‐ligand interfaces, and estimates of binding free energies of the resulting complexes. Our results provide the first quantitative information on the ligand abilities of nsLTPs, shed new light into protein‐lipid interactions, and reveal new features which supplement commonly held assumptions on their lack of binding specificity. © 2012 Wiley Periodicals, Inc.
Kinetics for the hydrogen‐abstraction of CH4 with NO2
Authors: Guan Yulei , Yang Bolun
Published: May 2012

The detailed mechanism of the NO2+CH4 reaction has been computationally investigated at the M06‐2X/MG3S, B3LYP/6‐311G(2d,d,p), and MP2/6‐311+G(2df,p) levels. The direct dynamics calculations were preformed using canonical transition state theory with tunneling correction and scaled generalized normal‐mode frequencies including anharmonic torsion. The calculated results indicate that the NO2+CH4 reaction proceeds by three distinct channels simultaneously, leading to the formation of trans‐HONO (1a), cis‐HONO (1b), and HNO2 (1c), and each channel involves the formation of intermediate having lower energy than the final product. The anti‐Hammond behavior observed in channel 1a is well analyzed. Proper treatment of anharmonic torsions about the C···H···O (or N) axis in the transition structures greatly improves the accuracy of kinetics predictions. The activation energy for each channel increases substantially with temperature, but is not strictly a linear function of temperature. Therefore, the thermal rate constants are fitted to the four‐parameter expression recommended for this case over the wide temperature range 400–4000 K. © 2012 Wiley Periodicals, Inc.
On Quasi‐Hermitian Varieties
Authors: Aguglia A. , Cossidente A. , Korchmáros G.
Published: May 2012

Quasi‐Hermitian varietiesinare combinatorial generalizations of the (nondegenerate) Hermitian varietyso thatandhave the same size and the same intersection numbers with hyperplanes. In this paper, we construct a new family of quasi‐Hermitian varieties. The isomorphism problem for the associated strongly regular graphs is discussed for.
Family Influences on Mania‐Relevant Cognitions and Beliefs: A Cognitive Model of Mania and Reward
Authors: Chen Stephen H. , Johnson Sheri L.
Published: May 2012

Objective

The present study proposed and tested a cognitive model of mania and reward.

Method

Undergraduates (N = 284; 68.4% female; mean age = 20.99 years, standard deviation ± 3.37) completed measures of family goal setting and achievement values, personal reward‐related beliefs, cognitive symptoms of mania, and risk for mania.

Results

Correlational analyses and structural equation modeling supported two distinct, but related facets of mania‐relevant cognition: stably present reward‐related beliefs and state‐dependent cognitive symptoms in response to success and positive emotion. Results also indicated that family emphasis on achievement and highly ambitious extrinsic goals were associated with these mania‐relevant cognitions. Finally, controlling for other factors, cognitive symptoms in response to success and positive emotion were uniquely associated with lifetime propensity towards mania symptoms.

Conclusions

Results support the merit of distinguishing between facets of mania‐relevant cognition and the importance of the family in shaping both aspects of cognition. © 2012 Wiley Periodicals, Inc. J. Clin. Psychol. 68:829‐842, 2012.
A Randomized Trial of MBSR Versus Aerobic Exercise for Social Anxiety Disorder
Authors: Jazaieri Hooria , Goldin Philippe R. , Werner Kelly , Ziv Michal , Gross James J.
Published: May 2012

Objective

Effective treatments for social anxiety disorder (SAD) exist, but additional treatment options are needed for nonresponders as well as those who are either unable or unwilling to engage in traditional treatments. Mindfulness‐based stress reduction (MBSR) is one nontraditional treatment that has demonstrated efficacy in treating other mood and anxiety disorders, and preliminary data suggest its efficacy in SAD as well.

Method

Fifty‐six adults (52% female; 41% Caucasian; age mean [M] ± standard deviation [SD]: 32.8 ± 8.4) with SAD were randomized to MBSR or an active comparison condition, aerobic exercise (AE). At baseline and post‐intervention, participants completed measures of clinical symptoms (Liebowitz Social Anxiety Scale, Social Interaction Anxiety Scale, Beck Depression Inventory‐II, and Perceived Stress Scale) and subjective well‐being (Rosenberg Self‐Esteem Scale, Satisfaction with Life Scale, Self‐Compassion Scale, and UCLA‐8 Loneliness Scale). At 3 months post‐intervention, a subset of these measures was readministered. For clinical significance analyses, 48 healthy adults (52.1% female; 56.3% Caucasian; age [M ± SD]: 33.9 ± 9.8) were recruited. MBSR and AE participants were also compared with a separate untreated group of 29 adults (44.8% female; 48.3% Caucasian; age [M ± SD]: 32.3 ± 9.4) with generalized SAD who completed assessments over a comparable time period with no intervening treatment.

Results

A 2 (Group) x 2 (Time) repeated measures analyses of variance (ANOVAs) on measures of clinical symptoms and well‐being were conducted to examine pre‐intervention to post‐intervention and pre‐intervention to 3‐month follow‐up. Both MBSR and AE were associated with reductions in social anxiety and depression and increases in subjective well‐being, both immediately post‐intervention and at 3 months post‐intervention. When participants in the randomized controlled trial were compared with the untreated SAD group, participants in both interventions exhibited improvements on measures of clinical symptoms and well‐being.

Conclusion

Nontraditional interventions such as MBSR and AE merit further exploration as alternative or complementary treatments for SAD. © 2012 Wiley Periodicals, Inc. J. Clin. Psychol. 68:715‐731, 2012
Illuminating a Neglected Clinical Issue: Societal Costs of Interpersonal Dependency and Dependent Personality Disorder
Authors: Bornstein Robert F.
Published: May 2012

Objectives

To determine the degree to which patients with high levels of trait dependency or dependent personality disorder (DPD) engage in behaviors that harm themselves and others (e.g., domestic violence, child abuse).

Method

Six domains of literature were reviewed: (a) dependency as a risk factor for physical illness; (b) health care utilization and expenditures; (c) global and domain‐specific functional impairment; (d) violence toward others; (e) victimization by others; and (f) self‐harm.

Results

High levels of trait dependency and DPD are associated with elevated risk for physical illness, partner and child abuse, and suicidality, as well as with high levels of functional impairment and increased health care expenditure.

Conclusions

Contrary to clinical lore, trait dependency and DPD are associated with behaviors that lead to myriad negative consequences for the dependent person, those close to them, and society as a whole. These patterns have noteworthy implications for assessment and treatment of dependent patients and suggest that DPD should be included as a diagnostic category in the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition. © 2012 Wiley Periodicals, Inc. J. Clin. Psychol. 68:766‐781, 2012
Intestinal and liver changes after chronic ketamine and ketamine plus alcohol treatment
Authors: Wong Yeuk W. , Lam L.H. , Tang H.C. , Liang Yong , Tan Sijie , Yew David T.
Published: May 2012

The effects of long‐term chronic ketamine treatment on the intestine and the liver were studied in the ICR mice which had daily intraperitoneal injection of ketamine at 30mg/kg per day for 7 months. The intestine showed no significant pathology after treatment but had a decrease of the positive sites of proliferative cell nuclear antigen in the mucosae of the intestines after ketamine and ketamine plus alcohol (added in the last month) treatment. No significant apoptosis (via TUNEL) nor necrosis (via lactic acid dehydrogenase) was detected in the intestines of all control and ketamine‐treated groups, with the exception of an increase of lactic acid dehydrogenase in the mucosae of the intestines of the ketamine plus alcohol group. In the liver, loss of glycogen was observed in animals after ketamine and ketamine plus alcohol treatment, in addition to the pathology reported in a previous work. The decrease in quantity of glycogen in the liver reflected either a failure of glycogen synthesis from glucose or an increase of glycogenolysis in the liver. Microsc. Res. Tech. 75:1170–1175, 2012. © 2012 Wiley Periodicals, Inc.
A novel whole tooth‐in‐jaw‐bone culture of rat molars: Morphological, immunohistochemical, and laser capture microdissection analysis
Authors: Chokechanachaisakul Uraiwan , Kaneko Tomoatsu , Yamanaka Yusuke , Okiji Takashi , Suda Hideaki
Published: May 2012

In conventional whole‐tooth culture systems, limitation exists regarding maintenance of the vitality of the dental pulp, because this tissue is encased in rigid dentin walls that hinder nutrition supply. We here report a whole tooth‐in‐jaw‐bone culture system of rat mandibular first molars, where transcardiac perfusion with culture medium was carried out before placement of the jaw bone into culture medium, aiming to facilitate longer time preservation of the dental pulp tissue. Following 7 days of culture, the pulp tissues were analyzed by histology and immunohistochemistry to ED2 (antiresident macrophage). ED2‐positive macrophages were also analyzed for their Class II MHC, interleukin‐6 (IL‐6), and p53 mRNA expression levels by means of immune‐laser capture microdissection (immune‐LCM). Dentin sialophosphoprotein (DSPP) mRNA expression in odontobalstic layer was also examined by LCM. Teeth cultured following saline‐perfusion and nonperfusion served as cultured controls. Normal teeth also served as noncultured controls. Histological examination demonstrated that the structure of the pulp tissue was well preserved in the medium‐perfused explants in contrast to the cultured control groups. The Class II MHC, IL‐6, and p53 mRNA expression levels of ED2‐positive cells and DSPP expression levels of odontoblastic layer tissues in the pulp of medium‐perfused explants were not significantly different from those in the noncultured normal teeth. In conclusion, the structural integrity and mRNA expression in the pulp were maintained at the in vivo level in the ex vivo whole tooth‐in‐jaw‐bone culture system. The system may lay the foundation for studies aiming at defining further histological and molecular mechanism of the pulp. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Toxicity of trifluralin herbicide in a representative of the edaphic fauna: Histopathology of the midgut of Rhinocricus padbergi (Diplopoda)
Authors: Merlini Vanessa Vanderléia , Nogarol Larissa Rosa , Marin‐Morales Maria Aparecida , Fontanetti Carmem Silvia
Published: May 2012

The aim of this study was to use the diplopod Rhinocricus padbergi as test organism to verify the possible toxic effects of the herbicide trifluralin in a representative of the edaphic fauna. Histological and histochemical techniques were applied in the midgut of the animals after exposure to different concentrations of trifluralin for 7 and 90 days (acute and subchronic exposure, respectively). The individuals from the control group did not present alterations to any of the exposures. In the acute exposure, the group exposed to a quarter and half of the field dose presented an accumulation of cytoplasmic granules in the hepatic cells; the field dose group presented an increase in the rate of epithelial renewal and the group exposed to double the field concentration presented an increase in the release of secretory vesicles. The subchronic response was obtained with the field dose and double field dose because the animals from a quarter and half groups did not survive until the end of the experiment. In both groups, the animals presented disruption of the epithelium and higher occurrence of hemocytes among the hepatic cells. The group exposed to double the field dose presented sites of cytoplasmic vacuolization, dilatation of the intercellular space, increase in the epithelial renewal, and release of secretory vesicles. The results alert for a careful use of this herbicide, since it promoted alterations in the midgut cells of the test organism used. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Effects of electrolytes on the fabrication of three‐dimensional nanoporous gold films by a rapid anodic potential step method for SERS
Authors: Xia Yue , Xu Yanzhen , Zheng Jufang , Huang Wei , Li Zelin
Published: May 2012

A unique one‐step anodic potential step strategy has been developed recently by our group to fabricate a three‐dimensional (3D) nanoporous gold film (NPGF) within 1 min as an efficient surface‐enhanced Raman scattering (SERS) active substrate. Gloria et al. (J. Electroanal. Chem. 2011, 656, 114–119) demonstrated that the prepared NPGF under optimum conditions (2 M HCl, 50 s) has higher SERS intensities than that of a commercial single‐use gold substrate. However, the SERS performance of 3D NPGFs fabricated in neutral KCl by this strategy have not been investigated. In this paper, SERS performances of the NPGFs fabricated in electrolytes of KCl and HCl are compared for the first time, using pyridine as a test molecule. Equivalent SERS intensities can be obtained on the 3D NPGFs prepared in these two electrolytes under respectively optimum conditions. The results suggest that hot spots of nanogaps and crevices because of the aggregation/coalescence of gold nanoparticles and the formation/removal of thin gold oxide coatings contribute greatly to the high SERS activity. Copyright © 2012 John Wiley & Sons, Ltd.
Origin of the variability of the mechanical properties of silk fibres: 2 The nanomechanics of single silkworm and spider fibres
Authors: Colomban Philippe , Dinh Hung Manh
Published: May 2012

The variability in mechanical stress–strain behaviour of various silks obtained from Bombyx mori silkworm and Nephila madagascarensis spider fibres has been studied by high resolution Raman analysis using the Raman shift induced by application of a controlled strain on the νN–H mode as a probe. Silk fibres exhibiting typical 1, 2, 3 and 4 Types have been selected from their characteristic tensile stress–strain behaviour. A perfect relationship between the nanomechanic (at the scale of the chemical bond) and macroscopic (silk single fibre) behaviour is observed as in the case of other polyamide fibres (natural keratin and synthetic PA66). Copyright © 2012 John Wiley & Sons, Ltd.
Meta‐analysis of safety for low event‐rate binomial trials
Authors: Shuster Jonathan J , Guo Jennifer D. , Skyler Jay S.
Published: May 2012

This article focuses on meta‐analysis of low event‐rate binomial trials. We introduce two forms of random effects: (1) ‘studies at random’ (SR), where we assume no more than independence between studies; and (2) ‘effects at random’ (ER), which forces the effect size distribution to be independent of the study design. On the basis of the summary estimates of proportions, we present both unweighted and study‐size weighted methods, which, under SR, target different population parameters. We demonstrate mechanistically that the popular DerSimonian–Laird (DL) method, as DL actually warned in their paper, should never be used in this setting. We conducted a survey of the major cardiovascular literature on low event‐rate studies and found that DL using odds ratios or relative risks to be the clear method of choice. We looked at two high profile examples from diabetes and cancer, respectively, where the choice of weighted versus unweighted methods makes a large difference. A large simulation study supports the accuracy of the coverage of our approximate confidence intervals. We recommend that before looking at their data, users should prespecify which target parameter they intend to estimate (weighted vs. unweighted) but estimate the other as a secondary analysis. Copyright © 2012 John Wiley & Sons, Ltd.
Generalization of trim and fill for application in meta‐regression
Authors: Weinhandl Eric D. , Duval Sue
Published: May 2012

Trim and fill is a popular method of accounting for publication bias in meta‐analysis. However, the use of trim and fill is limited to the setting in which all meta‐analyzed studies represent a true common effect. In many practical settings, within‐study effect estimates are a function of some covariate. Because methods of accounting for publication bias in meta‐regression have received little attention, we propose here a generalization of trim and fill for application in meta‐regression. The proposed algorithm preserves the computational features of trim and fill and adds only an assumption of symmetry in the hypothesized distribution of the measured covariate. By simulation, we evaluate properties (mean bias, root mean squared error, and coverage probability) of meta‐regression parameter estimates and corresponding confidence intervals with application of the proposed algorithm in a range of scenarios, including violation of the aforementioned assumption of symmetry. We also evaluate the performance of common estimators of the number of suppressed studies. In general, we show that the proposed algorithm is successful in identifying suppression of studies and reducing the bias in regression parameters derived from the analysis of the augmented set of studies. We apply the proposed algorithm to an analysis of the effect of cognitive–behavioral therapy on the risk of recidivism. Copyright © 2012 John Wiley & Sons, Ltd.
Preoperative thrombocytosis is associated with survival after surgery for colorectal cancer
Authors: Ishizuka Mitsuru , Nagata Hitoshi , Takagi Kazutoshi , Iwasaki Yoshimi , Kubota Keiichi
Published: May 2012

Objective

To evaluate the influence of preoperative thrombocytosis on survival after surgery in patients with colorectal cancer (CRC).

Methods

Four hundred fifty‐three patients who had undergone CRC surgery were retrospectively identified from institutional database. On the basis of receiver operating characteristic (ROC) curve analysis, they were classified into two groups: Group A, with a preoperative platelet count of ≤300 (×109/L), and Group B, with a preoperative platelet count of >300 (×109/L). Uni‐ and multivariate analyses were performed to evaluate the relationship to overall survival. Kaplan–Meier analysis and log rank test were used to compare the survival curves between groups A and B.

Results

There was a significant difference in overall survival between the two groups (P = 0.007). Multivariate analysis of selected preoperative clinicolaboratory characteristics showed that overall survival was associated with the platelet count (Group A/B) (odds ratio, 1.642; 95% CI, 1.025–2.629; P = 0.039) as well as the number of tumors (1/≥2), and the serum levels of C‐reactive protein (CRP) and carcinoembryonic antigen (CEA).

Conclusion

Preoperative thrombocytosis is associated with survival after surgery in CRC patients, and is able to divide such patients into two independent groups before surgery. J. Surg. Oncol. 2012; 106:887–891. © 2012 Wiley Periodicals, Inc.
The Role of Online Social Network Travel Websites in Creating Social Interaction for Gen Y Travelers
Authors: Nusair Khaldoon ‘Khal’ , Bilgihan Anil , Okumus Fevzi
Published: May 2012

This paper aims to evaluate Generation Y users' social interaction with online social networks (OSNs) by testing a theoretical model, which consists of antecedents and consequences of social interactions in an OSN travel context. An online self‐administered questionnaire was sent to a systematic random sample of 12 000 college students at six US universities, and 513 respondents in total participated in the study. Study results suggest that innovativeness, perceived utility, and information sharing are effective for developing online social interaction. The paper discusses theoretical and practical implications of study results and provides suggestions for future research. Copyright © 2012 John Wiley & Sons, Ltd.
Novel Cellulose/Polymer Blend Fibers Obtained Using Ionic Liquids
Authors: Ingildeev Denis , Hermanutz Frank , Bredereck Karl , Effenberger Franz
Published: May 2012

Combinations of cellulosic fibers (cotton, viscose) with man‐made chemical fibers (polyesters, polyamides, or polyacrylonitrile) are common as composites in textile fabrics. In this work the preparation of cellulose/polymer blend fibers in ILs is described. Cellulose is solved in ILs with other fiber polymers such as polyamides or PAN and processed to fiber blends by wet spinning. The rheology of spinning dopes, structural parameters, and physical textile properties of the prepared fibers are determined. TGA indicates a significant increase of carbon yield of the cellulose fibers blended with m‐aramide and PAN, respectively.

magnified image
Numerical modeling of hydrogen diffusion in structural steels under cathodic overprotection and its effects on fatigue crack propagation
Authors: Palma Carrasco J. , Silva Diniz D. , Andrade Barbosa J. M. , Almeida Silva A.
Published: May 2012

This paper presents a numerical simulation of the effect of hydrogen atomic diffusion on fatigue crack propagation on structural steels. The simulation was performed with a specimen type CT of API 5CT P110 steel, loaded in the tensile opening mode, in plane strain state and under the effects of a cyclic mechanical load and the hydrogen concentration at the crack tip. As hydrogen source, a cathodic protection system was considered, commonly used in subsea pipelines. The equations of evolution of variables at the crack tip form a non‐linear system of ordinary differential equations that was solved by means of the 4th order Runge‐Kutta method. The solid‐solid diffusion through the lattice ahead of the crack tip was simulated using the finite difference method. The simulations results show that under these conditions, the fatigue crack evolution process is enhanced by the hydrogen presence in the material, and that the start time of the crack propagation decreases as its concentration increases. These results show good correlation and consistency with macroscopic observations, providing a better understanding of hydrogen embrittlement in fatigue crack propagation processes in structural steels.
Identification of damage parameters for Ti‐6Al‐4V titanium alloy using continuum damage mechanics
Authors: Allahverdizadeh N. , Manes A. , Giglio M.
Published: May 2012

Modelling ductile damage is one of the most important applications of continuum damage mechanics (CDM) models. Scientists have previously tried to identify the damage parameters and have calibrated the failure behaviour of different materials using CDM models. However, more comprehensive studies are still needed to investigate the capabilities of CDM models for different materials. It is possible to extend the methodology to titanium alloys that are, currently, an optimal solution for highly stressed mechanical components. Therefore Lemaitre's CDM model parameters for ti‐6Al‐4V titanium alloy have been identified and reported in this work. A series of experimental tests have been carried out to identify the CDM model's parameters by the method of degradation of elastic modulus. A subroutine has been written in ABAQUS to numerically simulate the behaviour of the simple specimen using Lemaitre's model.
Laser beam cutting of metallic hollow sphere structures
Authors: Riegel H. , Merkel M. , Öchsner A.
Published: May 2012

Metallic hollow sphere structures (MHSS) represent a relatively new group of advanced composite materials characterised by high geometry reproduction leading to relatively constant mechanical and physical properties. The MHSS combine the well‐known advantages of cellular metals without major scattering of their material parameters. Various joining technologies such as sintering, soldering and adhering can be used to assemble single metallic hollow spheres to interdependent structures and allow adjusting different macroscopic properties. A machining process for MHSS has to reflect the special characteristic of the composite material. Classical mechanical cutting techniques like sawing or milling often fail. Spheres or large pieces are separated from the bulk structure and cause a rough surface at the cutting zone. Other cutting techniques like water jet cutting cannot be used for oxidising material. This paper presents laser beam cutting as a proper technique to cut composite materials like MHSS. The quality of the cutting zone strongly depends on the process parameter e. g. focal length, tool velocity and the structural characteristics of MHSS, e. g. density, sphere diameter and density. The experimental work was done using a CO2‐laser with a power of 1.5 kW. All investigations were done with sintered hollow sphere structures having different macroscopic properties. The maximum depth of a cut kerf was determined for four configurations of MHSS as function of laser velocities, gas pressure of the process gas, focal length of the lense. The depth was evaluated using a power balance of the laser input power on one side and the power needed to warm and melt the MHSS on the other side. A comparison between simulation and experiment of the width and the depth of the cut kerf shows, that the laser beam gets multiple reflections on the surfaces of the hollow spheres, enlarging the width of the cut kerf. The functional dependency between laser velocity and cut kerf depth can be estimated well. Theoretical and experimental results fit well together.
Finite element simulation of the macroscopic heat conductivity of syntactic perforated hollow sphere structures
Authors: Sulong M. A. , Öchsner A.
Published: May 2012

This work investigated the thermal properties of a new type of hollow sphere structures. For this new type, the sphere shell is perforated by several holes in order to open the inner sphere volume for a matrix material. The effective thermal conductivity of syntactic (i. e. spheres completely embedded in a matrix) perforated hollow sphere structures in a primitive cubic (PC) arrangement of unit cell models were numerically evaluated for different hole diameters, matrix volume fractions and different base materials. The results are compared to typical configurations without perforation. In the scope of this paper, three‐dimensional finite element analyses were used in order to investigate these unit cell models.
Approximating survivable networks with minimum number of steiner points
Authors: Kamma Lior , Nutov Zeev
Published: May 2012

Given a graph H = (U, E) and connectivity requirements r = {r(u,v) : u, v ∈ R ⊆ U}, we say that H satisfies r if it contains r(u, v) pairwise internally‐disjoint uv‐paths for all u, v ∈ R. We consider the Survivable Network with Minimum Number of Steiner Points (SN‐MSP) problem: given a finite set V of points in a normed space (M, ‖·‖) and connectivity requirements, find a minimum size set S ⊂ M \ V of additional points, such that the unit disc graph induced by U = V ∪ S satisfies the requirements. In the (node‐connectivity) Survivable Network Design Problem (SNDP) we are given a graph G = (V, E) with edge costs and connectivity requirements, and seek a minimum cost subgraph H of G that satisfies the requirements. Let k = maxu,v ∈ Vr(u, v) denote the maximum connectivity requirement. We will show a natural transformation of an SN‐MSP instance (V, r) into an SNDP instance (G = (V, E), c, r), such that an α‐approximation algorithm for the SNDP instance implies an α · O(k2)‐approximation algorithm for the SN‐MSP instance. In particular, for the case of uniform requirements r(u, v) = k for all u, v ∈ V, we obtain for SN‐MSP the ratio O(k2 ln k), which solves an open problem from (Bredin et al. Proceedings of the 6th ACM International Symposium on Mobile Ad Hoc Networking and Computing (MobiHoc) (2005), 309–319). © 2012 Wiley Periodicals, Inc. NETWORKS, 2012
Polycarbonate urethane films modified by heparin to enhance hemocompatibility and endothelialization
Authors: Lu Yue , Shen Li , Gong Feirong , Cui Jiayang , Rao Ju , Chen Jianding , Yang Wei
Published: May 2012

Polyurethane with pendant carboxyl groups was synthesized by a two‐step reaction using methylene diphenyl diisocyanate as hard segments, polycarbonate diols as soft segments and 2,2‐bis(hydroxymethyl) propionic acid as chain extenders. The surfaces of the casting polymer films were further covalently conjugated with heparin as confirmed by Fourier transform infrared spectroscopy. The associated surface‐exposed heparin content was measured to be 1.92 µg cm−2 and was shown to be active. Meanwhile, surface hydrophobicity decreased after heparin modification. Heparin immobilization greatly improved the hemocompatibility of polyurethane films both in vitro and in vivo. The in vitro cell responses revealed that the expression of proinflammatory markers CD106 and CD62E of human vein endothelial cells was significantly suppressed on the surfaces of the heparinized polyurethane films, while the affinity and proliferation of the cells were improved. The in vivo performance of this material before and after heparin modification was evaluated as a stent coating material in a porcine coronary artery injury model. Histological analysis indicated that heparinized polyurethane induced mild foreign body reactions and inflammation, which were much lower than those induced by unmodified polyurethane. Heparin immobilization also accelerated the endothelialization process on the surface of the polymer‐coated stents when implanted in porcine coronary arteries. More detailed long‐term studies are needed to confirm the biostability of the heparin and the endothelialized surfaces. Copyright © 2012 Society of Chemical Industry
Preparation of polymer microspheres with a rosin moiety from rosin ester, styrene and divinylbenzene
Authors: Yu Caili , Chen Chuanwei , Gong Qinhai , Zhang Fa‐Ai
Published: May 2012

Rosin was reacted with hydroxyethyl methacrylate to produce a macromonomer. This macromonomer was used to partly replace styrene for the novel preparation of polymer microspheres with divinylbenzene via suspension polymerization. Orthogonal experiments were conducted to analyze the factors influencing the particle size, particle size distribution, swelling ratio and degree of crosslinking of the polymer microspheres. Fourier transform IR spectroscopy, thermogravimetry and scanning electron microscopy were used to examine the structures, thermal properties and morphologies, respectively, of the polymer microspheres. The results showed that the amount of dispersant had the greatest influence on particle size and distribution. On the other hand, the monomer ratio greatly influenced the swelling ratio and degree of crosslinking of the polymer microspheres. The decomposition temperature of the polymer microspheres increased upon introduction of the rosin moiety into the product. Open pores were abundant on the surface of the polymer microspheres due to the existence of the porogen, which provided a base for adsorption and separation. The present study opens a novel route for using naturally occurring rosin. Copyright © 2012 Society of Chemical Industry
Interfacial agent effect on rheological response and crystallite characteristics in germicidal polypropylene/titanium dioxide nanocomposites
Authors: Serrano Cristina , Ressia Jorge A , Vallés Enrique M , Fernández‐García Marta , Cerrada María L
Published: May 2012

Germicidal nanocomposites based on metallocene isotactic polypropylene (iPP) and titanium dioxide (TiO2) nanoparticles have been prepared at a constant TiO2 content of 2 wt%. Different quantities of a polypropylene wax partially grafted with maleic anhydride (PP‐g‐MAH) are employed to improve the polymer‐nanoparticle compatibility. Remarkable biocidal capabilities of these TiO2 nanocomposites have been found and their crystalline structure and thermal and rheological responses explored. Several very interesting features have been found in these germicidal nanocomposites. On the one hand, rheological parameters do not change significantly with respect to those exhibited by pure iPP. This is extremely advantageous for the processing of these compounds since they can be transformed under similar conditions to those employed for iPP. On the other hand, the existence of two polymorphs is observed independent of the amount of compatibilizer used. The enhancement in polymer‐nanoparticle interactions by effect of the interfacial (PP‐g‐MAH) component is appraised looking at dynamical mechanical relaxations as a function of temperature and at crystallization processes of the various nanocomposites. Copyright © 2012 Society of Chemical Industry
Immunoproteomic identification of biotransformed self‐proteins from the livers of female Balb/c mice following chronic ethanol administration
Authors: Kaur Inderjeet , Katyal Anju
Published: May 2012

Chronic alcohol consumption culminates in alcoholic hepatitis which is characterized by ballooning degeneration of hepatocytes and perivenous inflammation. The aldehydes produced by ethanol oxidation and lipid peroxidation form adducts with the hepatic proteins rendering them immunogenic and initiating an autoimmune response. The present study was designed to identify these immunoreactive hepatic proteins in ethanol‐treated Balb/c mice. Liver cytosolic, mitochondrial, and microsomal proteins from the ethanol‐treated and control female Balb/c mice were size fractionated on SDS‐PAGE and immunoblotted with the sera from the individual animal. The immunoreactive proteins were identified using antimouse IgG antibody and characterized by MALDI‐TOF. It is the first report demonstrating that 15 hepatic proteins show immunoreactivity following alcohol administration. The identified autoreactive proteins ranged in function from metabolism to cytoskeletal support. Remarkably, three key enzymes of ethanol metabolism, namely alcohol dehydrogenase, aldehyde dehydrogenase I and III as well as important antioxidant enzyme glutathione S‐transferase were found to be autoreactive upon ethanol treatment. We conclude that ethanol treatment induces biotransformation of host proteins from almost every compartment of the cell, especially the enzymes involved in the detoxification of ethanolic insult being the major target for biotransformation. Hence, we propose that these proteins can be the potential candidates for the biomarker studies.
Evaluation of SCO1 deletion on Saccharomyces cerevisiae metabolism through a proteomic approach
Authors: Gamberi Tania , Puglia Michele , Bianchi Laura , Gimigliano Anna , Landi Claudia , Magherini Francesca , Guidi Francesca , Ranaldi Francesco , Armini Alessandro , Cipriano Maria , Gagliardi Assunta , Modesti Alessandra , Bini Luca
Published: May 2012

The Saccharomyces cerevisiae gene SCO1 has been shown to play an essential role in copper delivery to cytochrome c oxidase. Biochemical studies demonstrated specific transfer of copper from Cox17p to Sco1p, and physical interactions between the Sco1p and Cox2p. Deletion of SCO1 yeast gene results in a respiratory deficient phenotype. This study aims to gain a more detailed insight on the effects of SCO1 deletion on S. cerevisiae metabolism. We compared, using a proteomic approach, the protein pattern of SCO1 null mutant strain and wild‐type BY4741 strain grown on fermentable and on nonfermentable carbon sources. The analysis showed that on nonfermentable medium, the SCO1 mutant displayed a protein profile similar to that of actively fermenting yeast cells. Indeed, on 3% glycerol, this mutant displayed an increase of some glycolytic and fermentative enzymes such as glyceraldehyde‐3‐phosphate dehydrogenase 1, enolase 2, pyruvate decarboxylase 1, and alcohol dehydrogenase 1. These data were supported by immunoblotting and enzyme activity assay. Moreover, the ethanol assay and the oxygen consumption measurement demonstrated a fermentative activity in SCO1 mutant on respiratory medium. Our results suggest that on nonfermentable carbon source, the lack of Sco1p causes a metabolic shift from respiration to fermentation.
Proteomic analysis of spontaneous mutants of Lactococcus lactis: Involvement of GAPDH and arginine deiminase pathway in H2O2 resistance
Authors: Rochat Tatiana , Boudebbouze Samira , Gratadoux Jean‐Jacques , Blugeon Sébastien , Gaudu Philippe , Langella Philippe , Maguin Emmanuelle
Published: May 2012

Lactococcus lactis, one of the most commonly used dairy starters, is often subjected to oxidative stress in cheese manufacturing. A comparative proteomic analysis was performed to identify the molecular modifications responsible for the robustness of three spontaneous H2O2‐resistant (SpOx) strains. In the parental strain, glyceraldehyde‐3‐phosphate deshydrogenase (GAPDH) activity is ensured by GapB and the second GAPDH GapA is not produced in standard growth conditions. We showed that GapA was overproduced in the highly resistant SpOx2 and SpOx3 mutants. Its overproduction in the MG1363 strain led to an increased H2O2 resistance of exponential growing cells. Upon H2O2 exposure, GapB was fully inactivated by oxidation in the parental strain. In SpOx mutants, it partly remained in the reduced form sustaining partially GAPDH activity. The analysis of gapA disruption in these SpOx strains indicated that additional unraveled mechanisms likely contribute to the resistance phenotype. In the SpOx1 mutant, the arginine deiminase pathway was found to be upregulated and disruption of arcA or arcB genes abolished H2O2 resistance. We concluded that arginine consumption was directly responsible for the SpOx1 phenotype. Finally, these results suggest that sustaining energy supply is a major way of leading to oxidative stress resistance in L. lactis.
Proteome dynamics in primary target organ of infectious bursal disease virus
Authors: Wu Yongping , Peng Caie , Xu Li , Zheng Xiaojuan , Liao Min , Yan Yan , Jin Yulan , Zhou Jiyong
Published: May 2012

Viruses induce dramatic changes in target tissue during pathogenesis, including host cellular responses that either limit or support the pathogen. The infectious bursal disease virus (IBDV) targets primarily the bursa of Fabricius (BF) of chickens, causing severe immunodeficiency. Here, we characterized the cellular proteome changes of the BF caused by IBDV replication in vivo using 2DE followed MALDI‐TOF MS identification. Comparative analysis of multiple 2DE gels revealed that the majority of protein expression changes appeared between 24 and 96 h after IBDV infection. MS identified 54 altered cell proteins, 12 of which were notably upregulated by IBDV infection. Meanwhile, the other 42 cellular proteins were considerably suppressed by IBDV infection and are involved in protein degradation, energy metabolism, stress response, host macromolecular biosynthesis, and transport process. The upregulation of β‐actin and downregulation of dynamin during IBDV infection were also confirmed by Western blot and immunofluorescence analysis. These altered protein expressions provide a response profile of chicken BF to virulent IBDV infection. Further functional study on these altered proteins may lead to better understanding of pathogenic mechanisms of virulent IBDV infection and to new potential therapeutic targets.
Proteomic analysis of α4β1 integrin adhesion complexes reveals α‐subunit‐dependent protein recruitment
Authors: Byron Adam , Humphries Jonathan D. , Craig Sue E. , Knight David , Humphries Martin J.
Published: May 2012

Integrin adhesion receptors mediate cell–cell and cell–extracellular matrix interactions, which control cell morphology and migration, differentiation, and tissue integrity. Integrins recruit multimolecular adhesion complexes to their cytoplasmic domains, which provide structural and mechanosensitive signaling connections between the extracellular and intracellular milieux. The different functions of specific integrin heterodimers, such as α4β1 and α5β1, have been attributed to distinct signal transduction mechanisms that are initiated by selective recruitment of adhesion complex components to integrin cytoplasmic tails. Here, we report the isolation of ligand‐induced adhesion complexes associated with wild‐type α4β1 integrin, an activated α4β1 variant in the absence of the α cytoplasmic domain (X4C0), and a chimeric α4β1 variant with α5 leg and cytoplasmic domains (α4Pα5L), and the cataloguing of their proteomes by MS. Using hierarchical clustering and interaction network analyses, we detail the differential recruitment of proteins and highlight enrichment patterns of proteins to distinct adhesion complexes. We identify previously unreported components of integrin adhesion complexes and observe receptor‐specific enrichment of molecules with previously reported links to cell migration and cell signaling processes. Furthermore, we demonstrate colocalization of MYO18A with active integrin in migrating cells. These datasets provide a resource for future studies of integrin receptor‐specific signaling events.
Cell surface proteome of the marine planctomycete Rhodopirellula baltica
Authors: Voigt Birgit , Hieu Cao Xuan , Hempel Kristina , Becher Dörte , Schlüter Rabea , Teeling Hanno , Glöckner Frank Oliver , Amann Rudolf , Hecker Michael , Schweder Thomas
Published: May 2012

The surface proteome (surfaceome) of the marine planctomycete Rhodopirellula baltica SH1T was studied using a biotinylation and a proteinase K approach combined with SDS‐PAGE and mass spectrometry. 52 of the proteins identified in both approaches could be assigned to the group of potential surface proteins. Among them are some high molecular weight proteins, potentially involved in cell–cell attachment, that contain domains shown before to be typical for surface proteins like cadherin/dockerin domains, a bacterial adhesion domain or the fasciclin domain. The identification of proteins with enzymatic functions in the R. baltica surfaceome provides further clues for the suggestion that some degradative enzymes may be anchored onto the cell surface. YTV proteins, which have been earlier supposed to be components of the proteinaceous cell wall of R. baltica, were detected in the surface proteome. Additionally, 8 proteins with a novel protein structure combining a conserved type IV pilin/N‐methylation domain and a planctomycete‐typical DUF1559 domain were identified.
Proteome reference map of Drosophila melanogaster head
Authors: Lee Tian‐Ren , Huang Shun‐Hong , Lee Chi‐Ching , Lee Hsiao‐Yun , Chan Hsin‐Tzu , Lin Kuo‐Sen , Chan Hong‐Lin , Lyu Ping‐Chiang
Published: May 2012

Drosophila melanogaster has been used as a genetic model organism to understand the fundamental molecular mechanisms in human biology including memory formation that has been reported involving protein synthesis and/or post‐translational modification. In this study, we employed a proteomic platform based on fluorescent 2DE and MALDI‐TOF MS to build a standard D. melanogaster head proteome map for proteome–proteome comparison. In order to facilitate the comparison, an interactive database has been constructed for systematically integrating and analyzing the proteomes from different conditions and further implicated to study human diseases related to D. melanogaster model. In summary, the fundamental head proteomic database and bioinformatic analysis will be useful for further elucidating the biological mechanisms such as memory formation and neurodegenerative diseases.
A comparison of the bovine uterine and plasma proteome using iTRAQ proteomics
Authors: Faulkner Simon , Elia Giuliano , Mullen Michael P. , O'Boyle Padraic , Dunn Michael J. , Morris Dermot
Published: May 2012

Early embryo loss is a key factor affecting fertility in dairy and beef herds. Prior to implantation, the bovine embryo spends around 16 days free‐floating in the uterine environment and is dependent on the composition of uterine fluid for normal growth and development. However, there is a lack of information regarding the protein composition of the bovine uterus and how it relates to plasma. In this study, uterine flushings (UF) (n = 6) and blood plasma (n = 4) were collected from beef heifers on day 7 of the oestrous cycle, albumin depleted and compared using iTRAQ proteomics. A total of 35 proteins were higher and 18 were lower in UF including metabolic enzymes, proteins with anti‐oxidant activity and those involved in modulation of the immune response. This study confirms the dynamic nature of the bovine uterine proteome and that it differs from plasma. Factors affecting the uterine proteome and how it impacts on embryo survival warrant further study.