bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel benzimidazole‐containing phthalonitrile monomer with unique polymerization behavior
Authors: Wu Dimeng , Zhao Yongchao , Zeng Ke , Yang Gang
Published: August 2012

A novel benzimidazole‐containing phthalonitrile monomer (BIPN) was synthesized. The chemical structure of BIPN was confirmed by various spectroscopic techniques. Differential scanning calorimetry measurement revealed that the self‐promoted polymerization reaction of the BIPN proceeds extremely sluggish and showed low polymerization exothermic effect. Subsequent rheological measurement displayed that the BIPN was able to keep a stable and low melt viscosity for 4 h at 300 °C, 2 h at 310 °C, and 50 min at 330 °C. The derived BIPN polymers showed excellent thermal properties revealed by thermogravimetric analysis, which were better than those of the corresponding polymer derived from phthalonitrile monomer without benzimidazole moiety. IR analysis confirmed the occurrence of the triazine ring within the polymer crosslinking sites. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis and thiol‐responsive degradation of polylactide‐based block copolymers having disulfide junctions using ATRP and ROP
Authors: Ko Na Re , Yao Kejian , Tang Chuanbing , Oh Jung Kwon
Published: August 2012

A new method to synthesize a variety of well‐controlled polylactide (PLA)‐based block copolymers having disulfide linkages at block junctions (PLA‐ss‐PATRPs) was investigated. The method uses a combination of ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP) that initiates the synthesis of a new disulfide‐labeled double‐head initiator having both terminal OH and Br groups (HO‐ss‐iBuBr). The amount of tin catalyst and polymerization time significantly influenced the control of ROP initiated with HO‐ss‐iBuBr. A series of ATRP of various methacrylates as well as acrylate and styrene in the presence of the resulting PLA‐ss‐iBuBr macroinitiators proceeded in a living manner. These well‐controlled PLA‐ss‐PATRPs were further characterized for thermal properties using differential scanning calorimetry and thiol‐responsive degradation upon the cleavage of disulfide linkages. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym. Chem. 2013, 51, 3071–3080
Effects of Varying Heptylamine and Propionaldehyde Plasma Polymerization Parameters on Mesenchymal Stem Cell Attachment
Authors: Sandstrom Anne M. , Jasieniak Marek , Griesser Hans J. , Grøndahl Lisbeth , Cooper‐White Justin J.
Published: August 2012

This paper investigated the impacts of two deposition times (30 s, 60 s) and discharge powers (20 W, 50 W) on the resultant chemical and physical properties of plasma polymers (pp) formed using heptylamine (HA) or propionaldehyde (PA) monomers. Pinhole‐free pp films were formed on all surfaces at deposition rates that varied according to both the time and power employed. XPS and ToF‐SIMS analysis showed that power has a more of an effect than time on the chemical properties of the pp, which may be attributed to differences in monomer fragmentation and cross‐linking. Mesenchymal stem cell (MSC) adhesion did not vary on the four different HApp surfaces, whereas a negative correlation between cell attachment and increasing plasma energy was observed on PApp surfaces. This suggests that the presence of oxygenated groups, particularly aldehyde and carboxylic groups, may have a dominant impact on MSC adhesion to these functional polymer substrates.

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A call for a fresh new look at the plasma proteome
Authors: Hanash Samir
Published: August 2012

Serum and plasma from which serum is derived represent a substantial challenge for proteomics due to their complexity. A landmark plasma proteome study was initiated a decade ago by the Human Proteome Organization (HUPO) that had as an objective to examine the capabilities of existing technologies. Given the advances in proteomics and the continued interest in the plasma proteome, it would timely reassess the depth and breadth of analysis of plasma that can be achieved with current methodology and instrumentation. A collaborative project to define the plasma proteome and its variation, with a plan to build a plasma proteome database would be timely.
Electric‐field‐assisted crystallisation in phase‐change materials
Authors: Kohary Krisztian , Diosdado Jorge A. Vázquez , Ashwin Peter , Wright C. David
Published: August 2012

Phase‐change materials are of intense research interest due mainly to their use in phase‐change memory (PCM) devices that are emerging as a promising technology for future non‐volatile, solid‐state, electrical storage. Electrically driven transitions from the amorphous to the crystalline phase in such devices exhibit characteristic threshold switching. Several alternative electronic explanations for the origins of this characteristic behaviour have been put forward, for example Poole–Frenkel effects, delocalisation of tail states, field emission processes and space charge limited currents [for a full discussion, see Radielli et al., J. Appl. Phys. 103, 111101 (2008) and Simon et al., MRS Proc. 1251, H01–H011 (2010)]. However, an alternative to these conventional electronic models of threshold switching is based on electric field induced lowering of the system free energy, leading to the field induced nucleation of conducting crystal filaments. In this paper we investigate this alternative view. We present a detailed kinetics study of crystallisation in the presence of an electric field for the phase‐change material Ge2Sb2Te5. We derive quantitative crystallisation maps to show the effects of both temperature and electric field on crystallisation and we identify field ranges and parameter values where the electric field might play a significant role. Then we carry out physically realistic simulations of the threshold switching process in typical phase‐change device structures, both with and without electric field dependent energy contributions to the system free energy. Our results show that threshold switching can be obtained by a mechanism driven purely by electric field induced nucleation, but the fields so required are large, of the order of 300 MV m−1, and significantly larger than the experimentally measured threshold fields.
Crystal structure and electronic properties of the new structure dinitride–nitride N2MN (M: Cu, Ag)
Authors: Zhuravlev Yuriy , Lisitsyn Viktor , Morozova Yelena
Published: August 2012

Copper and nitrogen compounds and silver and nitrogen compounds have been researched with the first‐principle linear combination of the atomic orbitals in full‐screen basis with the local gradient and hybrid potential of the density functional theory (DFT) realized in the CRYSTAL09 program code. We have found the structural N2MN (M: Cu, Ag) dinitride–nitride phase having an orthorhombic structure, the spatial group of the Ibam symmetry and four formula units in the primitive cell that have not been reported before. The structure was found to be layered, the metal atoms are linearly circled by the nitride N atoms, whereas, the other two atoms make a molecule with a small negative charge of ∼0.02 e. The volume elastic modules in N2CuN, N2AgN crystals are equal to 4.3 and 6.6 GPa, respectively, and their pressure derivatives are equal to 6.7 and 5.3, respectively. The electron energy spectrum makes a superposition of weakly interacting molecular states of N2 and metal states of MN. The bandgap width equals ∼0.05 eV. The estimations of the enthalpy energies show that N2MN possess large energy content and in its decomposition into metal and gaseous nitride the energy release can reach 8 eV cell−1, which appears to be higher than that in the known metal azides. Thus, the new structure of the dinitride–nitride N2MN combines the properties of molecular and semiconductor crystals: high compressibility, strong mechanical anisotropy, localized vacant states in the zone spectrum, and small bandgap. The unique physical properties can ensure their application as energy materials, the source of chemically pure nitride, and in semiconductor and optical material science.
Towards a better understanding of intergranular phases in Fe–Nd–B sintered magnets
Authors: Goll Dagmar , Schweizer Stephanie , Wegierski Christian , Schneider Gerhard
Published: August 2012

Intergranular phases in Fe–Nd–B sintered magnets, which crystallize out of an under‐sintering liquid phase, form a complex structure below 655 °C and influence the magnetic properties. In model experiments the microstructure has been coarsened to study the thermodynamics and kinetics of the intergranular regions in the as‐sintered and as‐annealed condition. It is found that after sintering eutectic solidification products are present in the grain boundaries which are transformed during annealing at moderate temperatures. Similar results are observed in as‐cast Nd‐rich model samples.

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(© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estimation of secondary endpoints in two‐stage phase II oncology trials
Authors: Kunz Cornelia Ursula , Kieser Meinhard
Published: August 2012

In the development of a new treatment in oncology, phase II trials play a key role. On the basis of the data obtained during phase II, it is decided whether the treatment should be studied further. Therefore, the decision to be made on the basis of the data of a phase II trial must be as accurate as possible. For ethical and economic reasons, phase II trials are usually performed with a planned interim analysis. Furthermore, the decision about stopping or continuing the study is usually based on a short‐term outcome like tumor response, whereas secondary endpoints comprise stable disease, progressive disease, toxicity, and/or overall survival. The data obtained in a phase II trial are often analyzed and interpreted by applying the maximum likelihood estimator (MLE) without taking into account the sequential nature of the trial. However, this approach provides biased results and may therefore lead to wrong conclusions. Whereas unbiased estimators for two‐stage designs have been derived for the primary endpoint, such estimators are currently not available for secondary endpoints. We present uniformly minimum variance unbiased estimators (UMVUE) for secondary endpoints in two‐stage designs that allow stopping for futility (and efficacy). We compare the mean squared error of the UMVUE and the MLE and investigate the efficiency of the UMVUE. A clinical trial example illustrates the application. Copyright © 2012 John Wiley & Sons, Ltd.
Abusive Supervision and Workload Demands from Supervisors: Exploring Two Types of Supervisor‐related Stressors and their Association with Strain
Authors: Wu Tsung‐Yu , Hu Changya , Yang Chun‐Chi
Published: August 2012

Our study aimed to identify two types of stressors from supervisors: abusive supervision (AS) and workload demands from supervisors (WDS). AS reflects the relationship dimension of supervisor‐related stressors, and WDS reflects the task dimension of supervisor‐related stressors. In Study 1, we attempted to distinguish between AS and WDS. The results of confirmatory factor analysis showed that AS and WDS are two distinct dimensions of supervisor‐related stressors. In Study 2, we utilized job demands–resources model and investigated whether AS and WDS can uniquely predict subordinates' emotional exhaustion (EE). We also explored whether perceived job characteristics (PJCs) have differential moderating effects on the relationships between the two dimensions of supervisor‐related stressors (AS and WDS) and EE. Consistent with our predictions, the results showed that both AS and WDS have incremental predictive effects on EE after controlling for the effect of the other. The results also revealed that PJCs weaken the WDS–EE relationship, not the AS–EE relationship. We discussed the theoretical and practical implications at the end. Copyright © 2012 John Wiley & Sons, Ltd.
Stress and Coping Mediate Relationships between Contingent and Global Self‐Esteem and Alcohol‐Related Problems among College Drinkers
Authors: Tomaka Joe , Morales‐Monks Stormy , Shamaley Angelee Gigi
Published: August 2012

This study examined the hypotheses that contingent self‐esteem would be positively associated with alcohol‐related problems and that global self‐esteem would be negatively associated with such problems. It also examined the hypothesis that high stress and maladaptive coping would mediate these relationships. A sample of college students (n = 399) who were predominantly Hispanic (89%) completed measures of global and contingent self‐esteem; stress and coping; and alcohol‐related problems. Correlational and latent variable analyses indicated that contingent self‐esteem positively related to alcohol‐related problems, with maladaptive coping mediating this relationship. In contrast, global self‐esteem negatively related to such problems, a relationship that was also mediated by maladaptive coping and stress. Overall, the results highlight the potentially harmful consequences of contingent self‐worth and the adaptive nature of non‐contingent self‐esteem. They also demonstrate the important role that coping plays in mediating self‐esteem's associations with alcohol‐related problems. Copyright © 2012 John Wiley & Sons, Ltd.
Distance‐Mediated Plasmonic Dimers for Reusable Colorimetric Switches: A Measurable Peak Shift of More than 60 nm
Authors: Guo Longhua , Ferhan Abdul Rahim , Chen Hailan , Li Changming , Chen Guonan , Hong Seungpyo , Kim Dong‐Hwan
Published: August 2012

The first reconfigurable colorimetric DNA switches based on target DNA binding are reported. This DNA binding actuates a change in the interparticle distance between gold nanoparticle dimers. A significant spectral shift of 68 nm is achievable from on‐off switching. The reconfigurability is possible owing to thiol and EDC‐imidazole coupling which anchors the DNA linkers to the nanoparticles. The huge spectral shift allows the unaided eye to observe single target biomolecular binding event in real time under a darkfield microscope. The limit‐of‐detection for target molecules in PBS and human serum are 10−13 M and 10−11 M respectively. An improved fabrication strategy via asymmetric functionalization is also described, assisted by solid phase synthesis which minimizes the formation of trimers and multimers.
Why People Don't Ask: Understanding Initiation Behavior in International Negotiations
Authors: Volkema Roger J.
Published: August 2012

Negotiation is an interactive process that is important to all aspects of organizational success, a process that begins with communicating one's wants or needs. For many individuals, engaging others and asking for what one wants (i.e., initiating a negotiation) is a challenging task, made more difficult in an international context. Yet due to the integration of world markets, this is exactly the type of environment that many organizational representatives are facing with increasing regularity. This article offers an overview of the personal characteristics and situational factors that influence an individual initiating a negotiation (engaging a counterpart, making a request, and optimizing that request), with specific attention to seven cultural factors that must be understood to be most effective in international settings. The ways in which these cultural factors are likely to affect one's decision to engage a counterpart and style of delivery are illustrated for three countries: the United States, China, and Brazil. © 2012 Wiley Periodicals, Inc.
Shared Vision in MNE Subsidiaries: The Role of Formal, Personal, and Social Control in Its Development and Its Impact on Subsidiary Learning
Authors: Colakoglu Saba
Published: August 2012

Given the strategic importance of achieving global integration and worldwide learning for most multinational enterprises (MNEs), this article focuses on “shared vision” as a critical mechanism for realizing both goals. Specifically, this paper investigates the impact of three types of control mechanisms—formal (headquarters imposed rules and decisions), personal (the presence of expatriates), and social (social interaction among subunits) control—on building shared vision in subsidiaries and examines the subsequent impact of having shared vision on subsidiary learning. Overall, data from 99 subsidiaries located in the United States and headquartered either in Europe or Japan show that personal and social mechanisms of control are effective in building shared vision whereas formal control mechanisms have no impact. Results also support a significant relationship between shared vision and subsidiary learning. © 2012 Wiley Periodicals, Inc.
How Industry Dynamics Influence the Internationalization–Performance Relationship: Evidence From Technology‐Intensive Firms
Authors: Elango B.
Published: August 2012

The relationship between internationalization and performance has been the topic of a significant number of research studies, which report a mixed pattern of findings. However, the incorporation of global industry characteristics in the testing of this relationship has not been a facet of these studies. This article investigates the impact of intrafirm trade and differential market growth of the industry on the relationship between internationalization and performance. It focuses on technology‐intensive industries using a sample of 795 firms drawn from five countries. Findings indicate that internationalization has a positive relationship (which is quadratic in nature) with performance. Intrafirm trade and differential growth rates were found to interact with the relationship between internationalization and performance, thereby indicating the benefits of internationalization to be contingent on global industry characteristics. © 2012 Wiley Periodicals, Inc.
Global Social Media Usage: Insights Into Reaching Consumers Worldwide
Authors: Singh Nitish , Lehnert Kevin , Bostick Kathleen
Published: August 2012

This study documents global social media usage patterns based on a large‐scale survey of 4,630 social media users around the world. The study provides insights into how users in the European Union, United States, and BRIC (Brazil, Russia, India, and China) regions use social media for business and personal use. It analyzes variability in global social media platforms being used in these different world regions. The study also presents insights into usage of multilingual content for global social media consumption and the global user propensity to translate social media. Finally, the paper showcases an innovative technology solution to help companies leverage machine and human translation to enable users to translate social media content. © 2012 Wiley Periodicals, Inc.
Brazil Post‐Lula: Challenges and Opportunities Facing the Brazilian Business Environment
Authors: Gouvea Raul
Published: August 2012

The Brazilian economy indicates great potential for future economic growth. An increasing and affluent middle class, expanding exports, and foreign reserves are testimonies of Brazil's recent accomplishments. The country, however, still faces a number of challenges that may compromise its sustainable long‐term economic goals and objectives. This article focuses on the Luiz Inacio “Lula” da Silva government's economic performance. The article's main findings show increasing bottlenecks being created as a result of the Lula government's eight years of low economic growth rates, which have penalized the country's competitiveness. The newly elected president, Dilma Rousseff, will inherit a substantial investment deficit in the areas of infrastructure, education, health care, research and development (R&D), and innovation, as well as Brazil's worst public debt/gross domestic product (GDP) ratio in the past 100 years. These conditions will prevent Brazil from growing and developing at faster rates. This article also elaborates on Dilma Rousseff's most recent statements and discusses likely future paths for the Brazilian economy. © 2012 Wiley Periodicals, Inc.
Selling Time: Swatch Group and the Global Watch Industry
Authors: Anwar Syed Tariq
Published: August 2012

This illustrative case analyzes and evaluates Swatch Group and its core competencies and global strategies in the changing and highly segmented watch industry. Originating from Switzerland, the Group is a major watch manufacturer in the world with a unique brand portfolio that includes low priced as well as luxury watches such as Breguet, Blancpain, Longines, Rado, Omega, and the like. Swatch Group, formerly known as Socitéde Microélectronique et d'Horlogerie (SMH), sells its products through 500 Swatch watch shops, uses 15,000 retailers and 1,000 shop‐in‐shops, and over 140 kiosks in global markets. The Group is vertically integrated and supplies virtually all the components and parts for its line of watches. In 2009, Swatch Group's sales stood at $5.37 billion and the company continues to be an entrepreneurial entity with efficient research and development (R&D), creating many technological breakthroughs and marketing campaigns. Swatch Group is expected to grow in the coming years although the 2008 financial crisis, competition, and changing markets remain some of the major hurdles for the company. The article ends with selected developments and future changes that may impact the company in the coming years. © 2012 Wiley Periodicals, Inc.
Syntheses, Crystal Structures, and Properties of Lead(II), ­Zinc(II), and Manganese(II) Complexes Constructed from 2, 3, 5, 6‐Tetraiodo‐1, 4‐benzenedicarboxylic Acid
Authors: Hu Meng , Chen Sheng‐Chun , Zhang Zhi‐Hui , Wang Liang , Sun Fu‐An , Cui Ai‐Jun , He Ming‐Yang , Chen Qun
Published: August 2012

Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4](1) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for (3) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H···O and C–H···O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H···π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.
3D Coordination Polymers with Chiral Structures, [Ln2(tda)2(H2O)3]·5H2O: Hydrothermal Synthesis, Structural Characterization, and Luminescent Properties
Authors: Chen Chu‐Jun , Gao Jin‐Ying , Zhao Xia , Chang Li‐Mei , Liu Ying‐Liang , Mo Hai‐Hong , Yue Shan‐Tang
Published: August 2012

Reactions of H3tda (H3tda = 1H‐1, 2, 3‐triazole‐4, 5‐dicarboxylic acid) with Sm(NO3)3·6H2O, Eu(NO3)3·6H2O, and Tb(NO3)3·6H2O, in the presence of NaOH under hydrothermal conditions, produced three new coordination polymers, [Ln2(tda)2(H2O)3]·5H2O [Ln = Sm (1), Eu (2), Tb (3)]. These compounds were structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), PXRD and single‐crystal X‐ray diffraction. The single‐crystal X‐ray diffraction studies of compounds 1–3 reveal that all compounds are three‐dimensional porous structures with chiral frameworks. Furthermore, the luminescence studies of compound 2 and 3 in the solid state reveal that they are potential luminescent materials at room temperature.
Synthesis and Crystal Structure of the Cesium Silver ­Permanganate Cs3Ag[MnO4]4
Authors: Bauchert Jörg M. , Henning Harald , Schleid Thomas
Published: August 2012

After successful syntheses and structural refinements of the already known permanganates of cesium (Cs[MnO4]) and silver (Ag[MnO4]) we started to blend aqueous solutions of both components in various molar ratios. From crystallization experiments of these mixtures only three species of crystals with different chemical compositions were obtained: tricesium monosilver tetrakispermanganate (Cs3Ag[MnO4]4) and, depending upon the respective ratio, either additional silver permanganate or surplus cesium permanganate, namely. The new title compound crystallizes in the orthorhombic space group Pnnm (no. 58) with two formula units per unit cell and cell dimensions of a = 764.53(4), b = 1883.57(9) and c = 584.34(3) pm. The crystal structure of Cs3Ag[MnO4]4 consists of two crystallographically distinguishable cesium cations. (Cs1)+ is surrounded by fourteen oxygen atoms constructing a slightly distorted bicapped hexagonal prism. These polyhedra are connected through edge‐sharing with two other polyhedra of this kind to form chains along [001]. The chains are linked to each other via sixfold coordinated Ag+ cations (d(Ag–O) = 238–246 pm), arranged in such a manner that they link three oxygen atoms of two cesium polyhedra, leading to a two‐dimensional layer spreading out parallel to the (001) plane. Together with the two crystallographically different tetrahedral oxomanganate(VII) anions [MnO4]– (d(Mn–O) = 161–162 pm) the other kind of cesium cations ((Cs2)+ with CN = 13) finally connect these layers three‐dimensionally.
Does the Quality, Accuracy, and Readability of Information about Lateral Epicondylitis on the Internet Vary with the Search Term Used?
Authors: Dy Christopher J. , Taylor Samuel A. , Patel Ronak M. , McCarthy Moira M. , Roberts Timothy R. , Daluiski Aaron
Published: August 2012

Background

Concern exists over the quality, accuracy, and accessibility of online information about health care conditions. The goal of this study is to evaluate the quality, accuracy, and readability of information available on the internet about lateral epicondylitis.

Methods

We used three different search terms (“tennis elbow,”“lateral epicondylitis,” and “elbow pain”) in three search engines (Google, Bing, and Yahoo) to generate a list of 75 unique websites. Three orthopedic surgeons reviewed the content of each website and assessed the quality and accuracy of information. We assessed each website's readability using the Flesch-Kincaid method. Statistical comparisons were made using ANOVA with post hoc pairwise comparisons.

Results

The mean reading grade level was 11.1. None of the sites were under the recommended sixth grade reading level for the general public. Higher quality information was found when using the terms “tennis elbow” and “lateral epicondylitis” compared to “elbow pain” ( p<0.001). Specialty society websites had higher quality than all other websites ( p<0.001). The information was more accurate if the website was authored by a health care provider when compared to non-health care providers ( p=0.003). Websites seeking commercial gain and those found after the first five search results had lower quality information.

Conclusions

Reliable information about lateral epicondylitis is available online, especially from specialty societies. However, the quality and accuracy of information vary significantly with the search term, website author, and order of search results. This leaves less educated patients at a disadvantage, particularly because the information we encountered is above the reading level recommended for the general public.
Cryoconservation de spermatozoïdes avant vasectomie: utilité et paradoxes à travers l’activité des CECOS
Authors: Gillois P. , Rigot J. -M. , Juillard J. -C. ,   Fédération française des CECOS, Hennebicq S.
Published: August 2012

Le recours à la vasectomie demeure largement moins utilisé en France que dans d’autres pays comme le montrent les données présentées dans cet article. Par ailleurs, environ 12 % des hommes qui ont recours à ce moyen de stérilisation volontaire vont dans le même temps procéder à une congélation de spermatozoïdes. Proposer de préserver la fertilité d’hommes qui n’envisagent pas ou plus de projet de paternité peut apparaître paradoxal. Nous reprenons dans cet article les éléments de réglementation, réflexion et évolution au cours du temps de la pratique de la vasectomie combinée à la congélation de spermatozoïdes. Les données montrent qu’environ 5 % des hommes qui ont préservé leur fertilité avant la chirurgie demanderont ultérieurement une utilisation de ces spermatozoïdes, le plus souvent lors d’une nouvelle union. L’analyse de l’évolution des pratiques montre également qu’actuellement, le recours aux inséminations artificielles a été largement supplanté par l’utilisation des techniques de fécondation in vitro avec des chances de grossesse nettement supérieures. Enfin, au regard de l’évolution de la réglementation et de l’évolution des pratiques, nous posons la question de l’utilité de continuer à proposer une préservation de fertilité préalablement à la vasectomie et présentons des pistes de réflexion sur ce point.
Parent attachment, school commitment, and problem behavior trajectories of diverse adolescents
Authors: Cavendish Wendy , Nielsen Amie L. , Montague Marjorie
Published: August 2012

The purpose of this study was to examine the growth trajectories from early to late adolescence of teacher ratings of students' behavior problems from 9th through 11th grade and student self‐reports of alcohol use in a sample of predominately minority adolescents (n = 179, 90% African‐American and/or Hispanic, 43% boys, 57% girls) in a large, urban school district. The study investigated whether parent attachment, school commitment, gender, race/ethnicity, and educational placement influenced these outcomes. Multi‐level growth modeling was the primary statistical procedure used. Results indicated that increased parent attachment was associated with reduced levels of alcohol use and school commitment was not associated with growth trajectories of problem behavior in the multilevel models, although gender, race/ethnicity and special education placement were significant predictors. Our findings suggest that teachers perceive greater levels of behavior problems for minority students and youth in special education. Student self reports also indicate adolescent frequency of alcohol use increases over time.
Predictive value of negative cone margin status for risk of residual disease among women with cervical adenocarcinoma in situ
Authors: Kietpeerakool Chumnan , Khunamornpong Surapan , Srisomboon Jatupol , Kasunan Ajchara , Sribanditmongkol Narisa , Siriaungkul Sumalee
Published: August 2012

Objective

To determine the value of negative cone margins in predicting residual disease in women with adenocarcinoma in situ (ACIS).

Methods

Data were retrospectively analyzed from 60 women with ACIS who underwent conization at Chiang Mai University Hospital between March, 1998, and December, 2010. Negative margin status was defined as absence of neoplastic epithelium at all margins, coupled with presence of normal cervical epithelium. The association between the incidence of residual lesions and cone margin status was analyzed via χ2 or Fisher exact test.

Results

When adjusted for age and completeness of visualization of the cervical squamocolumnar junction during colposcopy, women who underwent loop electrosurgical excision procedure were 4 times more likely to have positive cone margins than those who underwent cold‐knife conization (95% CI, 1.13–16.43). Residual disease was not found among 26 women who had negative cone margins, but was observed in 17 (65.4%) of 26 women with positive cone margins (P < 0.001).

Conclusion

Women with ACIS who had negative cone margins were found to have a notably low risk of residual disease. Adherence to the standard method of cone sampling and criteria for negative margin status might contribute to a high predictive value of negative cone margins.
Shear instability of internal solitary waves in Euler fluids with thin pycnoclines
Authors: Almgren A. , Camassa R. , Tiron R.
Published: August 2012

The stability with respect to initial condition perturbations of solitary travelling-wave solutions of the Euler equations for continuously, stably stratified, near two-layer fluids is examined numerically and analytically for a set of parameters of relevance for laboratory experiments. Numerical travelling-wave solutions of the Dubreil–Jacotin–Long equation are first obtained with a variant of Turkington, Eyland and Wang’s iterative code by testing convergence on the equation’s residual. In this way, stationary solutions with very thin pycnoclines (and small Richardson numbers) approaching the near two-layer configurations used in experiments can be obtained, allowing for a stability study free of non-stationary effects, introduced by lack of numerical resolution, which develop when these solutions are used as initial conditions in a time-dependent evolution code. The thin pycnoclines in this study permit analytical results to be derived from strongly nonlinear models and their predictions compared with carefully controlled numerical simulations. This brings forth shortcomings of simple criteria for shear instability manifestations based on parallel shear approximations due to subtle higher-order effects. In particular, evidence is provided that the fore–aft asymmetric growth observed in all simulations requires non-parallel shear analysis. Collectively, the results of this study reveal that while the wave-induced shear can locally reach unstable configurations and give rise to local convective instability, the global wave/self-generated shear system is in fact stable, even for extreme cases of thin pycnoclines and near-maximum-amplitude waves.
Direct numerical simulation of axisymmetric wakes embedded in turbulence
Authors: Rind Elad , Castro Ian P.
Published: August 2012

Direct numerical simulation has been used to study the effects of external turbulence on axisymmetric wakes. In the absence of such turbulence, the time-developing axially homogeneous wake is found to have the self-similar properties expected whereas, in the absence of the wake, the turbulence fields had properties similar to Saffman-type turbulence. Merging of the two flows was undertaken for three different levels of external turbulence (relative to the wake strength) and it is shown that the presence of the external turbulence enhances the decay rate of the wake, with the new decay rates increasing with the relative strength of the initial external turbulence. The external turbulence is found to destroy any possibility of self-similarity within the developing wake, causing a significant transformation in the latter as it gradually evolves towards the former.
Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements
Authors: Liendo M.C. , Devescovi F. , Bachmann G.E. , Utgés M.E. , Abraham S. , Vera M.T. , Lanzavecchia S.B. , Bouvet J.P. , Gómez-Cendra P. , Hendrichs J. , Teal P.E.A. , Cladera J.L. , Segura D.F.
Published: August 2012

Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.
Current immunity markers in insect ecological immunology: assumed trade-offs and methodological issues
Authors: Moreno-García M. , Córdoba-Aguilar A. , Condé R. , Lanz-Mendoza H.
Published: August 2012

The field of ecological immunology currently relies on using a number of immune effectors or markers. These markers are usually used to infer ecological trade-offs (via conflicts in resource allocation), though physiological nature of these markers remains elusive. Here, we review markers frequently used in insect evolutionary ecology research: cuticle darkening, haemocyte density, nodule/capsule formation, phagocytosis and encapsulation/melanization via use of nylon filaments and beads, phenoloxidase activity, nitric oxide production, lysozyme and antimicrobial peptide production. We also provide physiologically based information that may shed light on the probable trade-offs inferred when these markers are used. In addition, we provide a number of methodological suggestions to improve immune marker assessment.
Larval morphology, development and forensic importance ofSynthesiomyia nudiseta(Diptera: Muscidae) in Europe: a rare species or just overlooked?
Authors: Velásquez Y. , Ivorra T. , Grzywacz A. , Martínez-Sánchez A. , Magaña C. , García-Rojo A. , Rojo S.
Published: August 2012

The muscidSynthesiomyia nudiseta(van der Wulp, 1883) is a species with forensic importance in tropical and subtropical regions of the world. This fly has recently been introduced into southern Europe and, until now, had not been recorded in forensic cases in this region. Here, morphology of all larval instars ofS. nudisetais documented in detail by using a combination of light and scanning electron microscopy. Literature data concerning larval morphology are revised and characters allowing identification from other forensically important Muscidae are listed. The life cycle of this species was studied at four constant temperatures: 15, 20, 25 and 30 °C. Total development varied between 46.50 ± 0.97 days at 15 °C and 15.39 ± 0.32 days at 30 °C. Moreover, we report this species breeding in human corpses, for the first time in Europe, in forensic cases from autopsies at the Anatomical Forensic Institute of Madrid and the Institute of Legal Medicine of Alicante, Spain.
Is there a link between faulting and magmatism in the south-central Aegean Sea?
Authors: KOKKALAS S. , AYDIN A.
Published: August 2012

A distinct spatial relationship between surface faulting, magmatic intrusions and volcanic activity exists in the Aegean continental crust. In this paper, we provide detailed structural observations from key onshore areas, as well as compilations of lineament maps and earthquake locations with focal plane solutions from offshore areas to support such a relationship. Although pluton emplacement was associated with low-angle extensional detachments, the NNE- to NE-trending strike-slip faults also played an important role in localizing the Middle Miocene plutonism, providing ready pathways to deeper magma batches, and controlling the late-stage emplacement and deformation of granites in the upper crust. Additionally, the linear arrangements of volcanic centres, from the Quaternary volcanoes along the active South Aegean Volcanic Arc, are controlled primarily by NE-trending faults and secondarily by NW-trending faults. These volcanic features are located at several extensional settings, which are associated with the main NE-trending faults, such as (i) in the extensional steps or relay zones between strike-slip and oblique-normal fault segments, (ii) at the overlap zones between oblique-normal faults associated with an extensional strike-slip duplex and (iii) at the tip zone of a NE-trending divergent dextral strike-slip zone. The NE trend of volcano-tectonic features, such as volcanic cone alignments, concentration of eruptive centres, hydrothermal activity and fractures, indicates the significant role of tectonics in controlling fluid and magma pathways in the Aegean upper crust. Furthermore, microseismicity and focal mechanisms of earthquakes in the area confirm the activity and present kinematics of these NE- trending faults.
South American Tours: Work Relations in the Entertainment Market in South America
Authors: Schettini Cristiana
Published: August 2012

This article explores the relationships between young European women who worked in the growing entertainment market in Argentine and Brazilian cities, and the many people who from time to time came under suspicion of exploiting them for prostitution. The international travels of young women with contracts to sing or dance in music halls, theatres, and cabarets provide a unique opportunity to reflect on some of the practices of labour intermediation. Fragments of their experiences were recorded by a number of Brazilian police investigations carried out in order to expel “undesirable” foreigners under the Foreigners Expulsion Act of 1907. Such sources shed light on the work arrangements that made it possible for young women to travel overseas. The article discusses how degrees of autonomy, violence, and exploitation in the artists’ work contracts were negotiated between parties at the time, especially by travelling young women whose social experiences shaped morally ambiguous identities as artists, prostitutes, and hired workers.
Temporary Labour Migration and State-Run Recruitment of Foreign Workers in Europe, 1919–1975: A New Migration Regime?
Authors: Rass Christoph
Published: August 2012

Temporary labour migration was one of the characteristic phenomena of human mobility in Europe during the twentieth century. The predominant answer in several European countries to the growing economic demand for an external labour supply on the one hand, and political demands to limit the numbers of foreign workers and to protect the native workforce from the competition of “cheap” migrant labour on the other, was a growing direct and active involvement of the nation state in regulatory efforts and recruitment operations abroad. Besides bureaucratic organizations on a national level, bilateral recruitment agreements – starting in their modern form in 1919 – became the most important tool to regulate labour migration between two countries. This article takes a look at the evolving system of bilaterally fixed migration relations in Europe and its implications for sending and receiving countries as well as for the labour migrants involved. It argues that the network of bilateral recruitment agreements provided controlled and selective migration channels in Europe between the 1950s and 1970s. These agreements installed and protected certain minimum standards to migrants and led to a general improvement of the rights and conditions offered to temporary labour migrants in Europe.
Labour Brokers in Migration: Understanding Historical and Contemporary Transnational Migration Regimes in Malaya/Malaysia
Authors: Kaur Amarjit
Published: August 2012

Labour brokerage and its salient role in the mobility of workers across borders in Asia has been the subject of recent debate on the continuing usefulness of intermediaries in labour mobility and migration processes. Some researchers believe that labour brokerage will decline with the expansion of migrant networks, resulting in reduced transaction costs and a better deal for migrant workers. From an economic standpoint, however, reliance on brokers does not appear to have a “use-by date” in south-east Asia. Labour brokers have played an important role in organizing and facilitating officially authorized migration, particularly during the contemporary period. They undertake marketing and recruitment tasks, finance migrant workers’ travel, and enable transnational labour migration to take place. Consequently, both sending and destination states have been able to concentrate on their role as regulatory “agencies”, managing migration and ensuring compliance with state regulatory standards and providing labour protection. Private recruitment firms have simultaneously focused on handling the actual recruitment and placement of migrant workers. Notwithstanding this, the division of responsibilities in the migration regimes has also led to uncontrolled migration and necessitated intervention by the state during both periods. These interventions mirror the ethos of the times and are essential for understanding past and present political environments and transnational labour migration in south-east Asia.
Reversal of Young's procedure in hereditary haemorrhagic telangiectasia
Authors: Oozeer N B , Bingham B J
Published: August 2012

Background:

Hereditary haemorrhagic telangiectasia is an autosomal dominant condition characterised by multiple venous malformations of the skin and mucous membranes which can bleed on contact. A Young's procedure is used to control severe epistaxis in patients with this condition. However, there has been no previous report of a reversal of Young's procedure in such a patient.

Objective:

A patient with hereditary haemorrhagic telangiectasia had his Young's procedure reversed under general anaesthetic by dividing the mucocutaneous flaps. Nasal vestibule patency was maintained using a custom-made silicone nasal mould. Intra-operative photographs show the patient's nasal mucosa shortly following reversal of his Young's procedure, and also illustrate the creation of the custom-made nasal mould.

Conclusion:

Stopping airflow through the nasal cavity via a Young's procedure prevents the telangiectasia from bleeding but does not make them disappear completely. Young's procedure does not seem to have any long-lasting effect on the nasal mucosa of patients with hereditary haemorrhagic telangiectasia.
Plasma-driven Z-pinch X-ray loading and momentum coupling in meteorite and planetary materials
Authors: REMO JOHN L. , FURNISH MICHAEL D. , LAWRENCE R. JEFFERY
Published: August 2012

X-ray momentum coupling coefficients, CM, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Velocity interferometry (VISAR) diagnostics provided equation-of-state data. Targets were iron and stone meteorites, magnesium-rich olivine (dunite) solid and powder (~5–300 μm), and Si, Al, and Fe calibration targets. Samples were ~1-mm thick and, except for Si, backed by LiF single-crystal windows. X-ray spectra combined thermal radiation (blackbody 170–237 eV) and line emissions from pinch materials (Cu, Ni, Al, or stainless steel). Target fluences of 0.4–1.7 kJ/cm2 at intensities of 43–260GW/cm2 produced plasma pressures of 2.6–12.4 GPa. The short (~5 ns) drive pulses gave rise to attenuating stress waves in the samples. The attenuating wave impulse is constant, allowing accurate CM measurements from rear-surface motion. CM was 1.9 − 3.1 × 10−5 s/m for stony meteorites, 2.7 and 0.5 × 10−5 s/m for solid and powdered dunite, 0.8 − 1.4 × 10−5 s/m for iron meteorites, and 0.3, 1.8, and 2.7 × 10−5 s/m respectively for Si, Fe, and Al calibration targets. Results are consistent with geometric scaling from recent laser hohlraum measurements. CTH hydrocode modeling of X-ray coupling to porous silica corroborated experimental measurements and supported extrapolations to other materials. CTH-modeled CM for porous materials was low and consistent with experimental results. Analytic modeling (BBAY) of X-ray radiation-induced momentum coupling to selected materials was also performed, often producing higher CM values than experimental results. Reasons for the higher values include neglect of solid ejecta mechanisms, turbulent mixing of heterogeneous phases, variances in heats of melt/vaporization, sample inhomogeneities, wave interactions at the sample/window boundary, and finite sample/window sizes. The measurements validate application of CM to (inhomogeneous) planetary materials from high-intensity soft X-ray radiation.