bluuebunny/crossref_metadata_2025 huggingface dataset:
A High-Volume Cryosampler and Sample Purification System for Bromine Isotope Studies of Methyl Bromide*
Authors: Thornton Brett F. , Horst Axel , Carrizo Daniel , Holmstrand Henry , Andersson Per , Crill Patrick M. , Gustafsson Örjan
Published: May 2013

A system was developed for collecting from the ambient atmosphere the methyl halides CH3Cl and CH3Br in quantities sufficient for chlorine and bromine isotope analysis. The construction and operation of the novel cryogenic collection system (cryosampler) and sample purification system developed for this task are described. This study demonstrates the capability of the cryosampler by quantifying the CH3Cl and CH3Br collected from atmospheric samples and the nonfractionating bromine isotope fingerprint of CH3Br from synthetic air samples of controlled composition. An optimized cryosampler operation time of 4 h at a flow rate of 15 L min−1 is applied to yield the nearly 40 ng required for subsequent δ81Br-CH3Br analyses. The sample purification system is designed around a packed column gas chromatography–quadropole–mass spectrometry (GCqMS) system with three additional cryotraps and backflushing capacity. The system's suitability was tested by observing both the mass recovery and the lack of Δ81Br isotope fractionation induced during sample purification under varying flow rates and loading scenarios. To demonstrate that the entire system samples and dependably delivers CH3Br to the isotope analysis system without inducing isotope fractionation, diluted synthetic air mixtures prepared from standard gases were processed through the entire system, yielding a Δ81Br-CH3Br of +0.03‰ ± 0.10‰ relative to their starting composition. Finally, the combined cryosampler–purification and analysis system was applied to demonstrate the first-ever δ81Br-CH3Br in the ambient atmosphere with two samples collected in the autumn of 2011, yielding −0.08‰ ± 0.43‰ and +1.75‰ ± 0.13‰ versus standard mean ocean bromide for samples collected at a suburban Stockholm, Sweden, site.
Migration and the Transition to Adulthood in Contemporary Malawi
Authors: Beegle Kathleen , Poulin Michelle
Published: May 2013

This article investigates the relationship among major life events, household characteristics, and migration among adolescents and young adults in contemporary Malawi. Two main questions are investigated: What are the socioeconomic and demographic determinants of migration? and How do schooling, first marriage, and work relate to migration patterns? The study uses panel data collected from a survey designed specifically to explore socioeconomic and demographic aspects of youths’ transitions to adulthood. Respondents were tracked when they moved. Moves are not uncommon, and the predominant reasons for moves are noneconomic. Although historically ethnic traditions in this area have held that girls and women usually do not move upon marrying, young women are now more likely to move than young men, with marriage being a main reason for doing so. Closer ties to the head of the household are associated with less movement for both women and men.
Transitioning from School to Work as a Mexican 1.5er
Authors: Rojas-García Georgina
Published: May 2013

This is a qualitative study that examines the process through which young adults who were born in Mexico and immigrated to the United States in their formative years have managed to attain a college education, and the uncertainty that besets their future careers. The article focuses on successful college attainment but seeks to add to the debate about resilient migrants along the following lines. The young adult immigrant population (referred to as Generation 1.5) deserves special attention since they experience a different process of socialization and insertion into American society, compared to first-generation adult migrants and to their children born in the United States (the second generation). The outcome of this different socialization process is a group of high achievers in the academic arena, with a heterogeneous prospect in labor, mainly due to their migratory situation. Their professional prospects fall into one of two patterns: upward mobility or glass-ceiling mobility.
Migration as a Risk Factor for HIV Infection among Youths in Sub-Saharan Africa
Authors: Magadi Monica A.
Published: May 2013

Of the estimated 10 million youths living with HIV worldwide, 63 percent live in sub-Saharan Africa. This article focuses on migration as a risk factor of HIV infection among the youths in sub-Saharan Africa. The study is based on multilevel modeling, applied to the youth sample of the Demographic and Health Surveys (DHS), conducted from 2003 to 2008 in nineteen countries. The analysis takes into account country-level and regional-level variations. The results suggest that across countries in sub-Saharan Africa, migrants have on average about 50 percent higher odds of HIV infection than nonmigrants. The higher risk among migrants is to a large extent explained by differences in demographic and socioeconomic factors. In particular, migrants are more likely to be older, to have been married, or to live in urban areas, all of which are associated with higher risks of HIV infection. The higher risk among youths who have been married is particularly pronounced among young female migrants.
Social Exclusion and Young Rural-Urban Migrants’ Integration into a Host Society in China
Authors: Yang Juhua
Published: May 2013

This article explores correlates of the socioeconomic integration of young rural-urban migrants in a host society in China. Using a new typology that distinguishes hukou (household registration system), migration status, and age, multilevel modeling results indicate that young rural-urban migrants achieve a lower socioeconomic status than local youths and urban-urban migratory youths. This challenges the notion that marketization necessarily promotes rights and legal equality in a linear fashion and suggests that the potentially positive impact of migration on personal development might be compromised by institutional constraints (e.g., hukou) that exclude migrants from rural areas, as well as other outsiders, particularly youths.
Unaccompanied Young Migrants from Africa
Authors: Tanon Fabienne , Sow Abdoulaye
Published: May 2013

Unaccompanied minors and youth migrants from Mauritania to France are almost never listed in French published statistics, even though the alarmist response of local Mauritanian organizations indicates that many are migrating. To understand this apparent contradiction, we analyze data from a qualitative study of 395 male minors (15–18 years old) and youths (above 18 years old) in three Mauritanian cities—Kaédi, Nouakchott, and Nouadhibou—to shed light on illegal youth migration. We find that powerful cultural and family dynamics encourage youth migration and that the migration of individual youths is approached as a project of families and not of the individuals alone. The article also highlights the impact of migration on Mauritanian society and recommends a new immigration policy for Europe.
Watch the Crowd
Authors: Braun Robert , Koopmans Ruud
Published: May 2013

Social movement scholars have struggled with the question how abstract political opportunities affect activists without much knowledge of politics. We argue that the relationship between institutional opportunities and mobilization may take the form of trickle-down politics. In this view, activists are affected by political opportunities indirectly through the changes that political developments bring about in the immediate setting of protest. The political climate determines the distance between general public opinion and activists’ view on society. The smaller this distance, the more likely it becomes that activists receive positive feedback, which results in further mobilization. We investigate how activists are influenced by bystander responses that are evoked by the wider political context. Statistical models indeed indicate that spatiotemporal fluctuations in political opportunities and public sentiments are translated into mobilization after activists receive feedback from bystanders. This suggests that bystander responses play a crucial role in linking political opportunities to mobilization.
Educator Beliefs and Cultural Knowledge
Authors: Nelson Sarah W. , Guerra Patricia L.
Published: May 2013

Purpose: This qualitative study reports on beliefs practicing educators hold about diverse students and families. Specifically, this study examined educator beliefs related to culturally, linguistically, and economically diverse students and families along with participants’ knowledge of culture and its application in practice. Research Design: Data were collected through a qualitative instrument administered to 111 teachers and educational leaders in two school districts in Texas and Michigan. Participants provided written responses to scenarios depicting culture clashes that commonly occur in schools. Data were analyzed using a constructivist grounded theory resulting in a continuum of cultural responsiveness. Findings: Results reveal the majority of participants appear to have a general awareness of culture, but also hold a number of deficit beliefs about diverse students and their families. In describing how they apply cultural knowledge in practice, participants tended to address visible aspects of culture, overlooking less obvious aspects. The majority of participants used deficit thinking in explanations for the clashes and viewed the clashes as problems warranting a technical solution. Little consideration was given to the social aspects of schooling such as identity, culture, language, and relationships, which are at the heart of culturally responsive teaching, learning, and leading. Implications: More than 30 years of school reform efforts have failed to address inequitable educational outcomes. The results of this study suggest the ineffectiveness of reform efforts may be due in part to educators’ deficit beliefs and lack of cultural knowledge, two areas preparation and professional development programs must better address.
Temporality, narration and the problem of history: A view from Western India c. 1100–1400
Authors: Ali Daud
Published: May 2013

The articles in this issue contribute to a paradigm shift in our approaches to historical discourse in precolonial South Asia. Rather than posing again the well-worn question of whether the Rājataraṅgiṇī should be considered a properly ‘historical’ text or a work of poetry, they focus on the complex and often hybrid sytlistic, thematic and aesthetic ‘lineages’ of the text, to understand how Kalhaṇa was able to articulate a unique vision of the past—and one that created the space for further iterations in later times. This final article seeks to at least partly test the value of such an approach through a similar examination of largely contemporaneous materials from Western India. Long noted for its peculiar combination of tantalising historical detail with magical elements and chronological anachronisms, the prabandha literature of Gujarat has recently been interpreted as an expression of a ‘Jain’ approach to kingship, morality and biography. Without denying this obvious connection, this article approaches the prabandhas by contexualising them against the wider background of temporalities and narrational styles in Sanskrit literature. It argues that the peculiar conventions of prabandha literature in Western India may best be explained through the interaction of distinctive narrative traditions and temporal orientations in Sanskrit writing that may have broad parallels in Kashmir’s literary history.
The difference between a poet and a prophet: Dialectical rhetoric and the role of the Spirit in preaching, with reference to Karl Barth and D. Martyn Lloyd-Jones
Authors: Edwards Aaron
Published: May 2013

Do preachers really preach? Aiming for the relative safety of the ‘both/and’, many preachers slip into sermonizations of the Word of God, neglecting the activity of the Spirit. Barth’s early preaching (especially the infamous ‘Titanic sermon’) often flaunts rhetoric and ‘paradox’ rather than heraldic proclamation. Famous preacher Martyn Lloyd-Jones was well known for his criticisms of Barth’s dialectical theology. Though rarely considered as feasible interlocutors, Lloyd-Jones’s call for prophetic ‘unction’ in preaching reveals a remarkably similar homiletic to the later Barth. Preaching as ‘prophecy’ emphasizes the active expectation of the preacher to be impacted by the power of the Spirit.
The construct validation of the Relationship Harmony and Soft-Heartedness Scales of the South African Personality Inventory
Authors: Hill Carin , French Luan , Morton Nadia , van de Vijver Fons JR , Valchev Velichko H , Adams Byron G , de Bruin Gideon P
Published: May 2013

This study forms part of the South African Personality Inventory project that aims to develop: (a) an indigenous theoretical model of personality; and (b) a unique personality measure that is in line with South African legislation and that can be used fairly to assess personality across different South African language and cultural groups. In line with this mandate, the objectives in this study were twofold: first, to validate the Relationship Harmony and Soft-Heartedness Scales of the South African Personality Inventory and to determine whether these constructs are unique and distinct from the Big Five personality factors, and second, to determine whether Relationship Harmony and Soft-Heartedness are predictive of an external criterion, prosocial behaviour. A quantitative, cross-sectional research design with convenience sampling was used. Data were gathered from students ( N = 431) at two tertiary institutions in South Africa, using preliminary Relationship Harmony and Soft-Heartedness Scales, the Basic Traits Inventory (Short form: Research Version), and the Prosocialness Scale. Results indicated that the Relationship Harmony and Soft-Heartedness Scales yielded five and six reliable factors, respectively, and presented good content, convergent, discriminant, and predictive validity, adding substantial predictive value for prosocial behaviour over and above the Big Five Model.
Post-traumatic stress disorder in patients with spinal-cord injuries
Authors: Moodley Nancy , Pillay Basil J
Published: May 2013

The majority of spinal-cord injuries result from traumatic incidents such as motor vehicle accidents, falls, and acts of violence such as stab and gunshot wounds. Given the traumatic and life-threatening nature of most spinal-cord injuries, especially in a country like South Africa, where there is a high level of violent crime, post-traumatic stress disorder can be a common consequence for many patients. Using a prospective design, a total of 112 traumatic spinal-cord-injured patients, drawn from government hospitals in the Durban (South Africa) metropolitan and surrounding areas, were assessed. The control group consisted of 79 patients who had amputations. Post-traumatic stress disorder was assessed using the Impact of Event Scale–Revised and Post-Traumatic Diagnostic Scale. In addition, a semi-structured interview was conducted and supplementary data were obtained from each patient’s file. The results indicated a high rate of post-traumatic stress disorder following traumatic spinal-cord injuries. Road traffic accidents were the most common cause of traumatic spinal-cord injuries. Single young males were found to be at greater risk of sustaining such injuries. The results and discussion emphasise the ubiquitous multicultural issues that influence outcomes. This study highlights the need for psychological intervention following traumatic spinal-cord injuries due to the high rate of post-traumatic stress disorder symptoms.
Offenders’ Perceptions of RiskFactors for Self and Others
Authors: Brooks Holliday Stephanie , King Christopher , Heilbrun Kirk
Published: May 2013

Little research has examined offenders’ understanding of the factors that increase their likelihood of future criminal activity. Although social-psychological research has described many ways in which individuals have overly positive views of themselves and their performance, a more limited body of literature has demonstrated that offenders exhibit an unrealistically optimistic perception of their success upon release from incarceration. A survey designed to assess offender understanding of general risk factors and their own risk factors was administered to male offenders (N = 88) returning to the community from prison incarceration. Results suggest that these individuals have an appreciation for the factors that generally increase the risk of future offending, but do not perceive these factors as personally relevant. In addition, the concordance between offender-identified and Level of Service/Case Management Inventory–identified risk factors was limited. Implications of this lack of understanding, and ways to improve upon this knowledge, are discussed.
Correlation between rheological and dielectric percolation of conductive carbon black-filled ethylene acrylic elastomer
Authors: Sahoo Bibhu Prasad , Naskar Kinsuk , Tripathy Deba K
Published: May 2013

Conductive rubber composites based on ethylene acrylic elastomer (AEM) and conductive carbon black (CCB) were prepared by a two-roll mixing mill. From the transmission electron microscope photomicrographs, the uniform distribution of CCB aggregates and the interconnected CCB aggregates in the AEM matrix were observed. The bound rubber content of unvulcanized rubber was found to increase significantly with increasing CCB content. The effect of CCB concentration on the dynamic viscoelastic properties of AEM matrix was determined using a Rubber Process Analyzer (RPA 2000) in terms of strain sweep and frequency sweep of both uncured and cured AEM/CCB systems. The storage modulus ( G′) increased with an increase in CCB loading. In the case of strain sweep, the G′ values decreased with strain amplitude for both the systems, but the G′ was more for cross-linked AEM/CCB systems. The strain dependency of G′ for CCB-filled AEM systems can be explained on the basis of the Payne effect. The complex viscosity ( η*) of these systems increased with CCB loading, and it decreased with strain amplitude, which is due to the shear thinning effect. The tan  δ for unvulcanized and vulcanized systems increased with the strain; however, the value of tan  δ was <1 throughout the experimental strain range, which explains the elastic nature of the cured systems. The G′ increased with angular frequency for both the systems and the tan  δ became independent upon the angular frequency after 10 Hz. The alternating current conductivity ( σAC) increased with an increase in CCB loading at all frequencies and the system achieves the percolation at 20 phr CCB loading, which is in accordance with the rheological percolation. The direct current conductivity (σDC) also increased with an increase in CCB concentration.
States of Abjection
Authors: Rizq Rosemary
Published: May 2013

This paper draws on Kristeva’s (1982) notion of abjection to conceptualize the nature of organizational defences against anxiety. The abject is that aspect of the self which lies outside the symbolic order, evoking feelings of anxiety, disgust, repulsion and fear. These feelings index the attempt by the individual to distance the self from what is felt to be improper or unclean in order to establish subjectivity and identity. Located within UK public mental health services which have recently been subject to New Public Management restructuring, the paper explores how contemporary preoccupations with regulation, surveillance and governance in public mental health institutions may be characterized as a symbolic attempt to gain mastery over feelings unconsciously deemed to be abject reminders of the body. A short case example drawn from my work as psychotherapist and supervisor in a primary care mental health service is offered to illustrate how feelings of psychological distress come to be abjected within the organization. I conclude by proposing that theorizing abjection offers rich prospects for future debate and research within the field of organization studies.
Political Apologies and the Question of a ‘Shared Time’ in the Australian Context
Authors: Bastian Michelle
Published: May 2013

Although conceptually distinct, ‘time’ and ‘community’ are multiply intertwined within a myriad of key debates in both the social sciences and the humanities. Even so, the role of conceptions of time in social practices of inclusion and exclusion has yet to achieve the prominence of other key analytical categories such as identity and space. This article seeks to contribute to the development of this field by highlighting the importance of thinking time and community together through the lens of political apologies. Often ostensibly offered in order to re-articulate both the constitution of ‘the community’ and its future direction, official apologies are prime examples of deliberate attempts to intervene in shared understandings of political community and its temporality. Offering a detailed case study of one of these apologies, I will focus on Australian debates over the removal of indigenous children from their families, known as the Stolen Generations, and examine the temporal dimensions of the different responses offered by former prime ministers John Howard and Kevin Rudd.
Local hemodynamic disturbance accelerates early thrombosis of small-caliber expanded polytetrafluoroethylene grafts
Authors: Lu S , Sun X , Zhang P , Yang L , Gong F , Wang C
Published: May 2013

Objective:

Small-caliber expanded polytetrafluoroethylene (ePTFE) grafts cannot be used widely in the clinical situation because of early thrombosis and occlusion. This unsolved and under-recognized problem warrants further investigation.

Methods:

Grafts of uncoated ePTFE (n = 6) and anti-CD34-coated ePTFE (n = 6) were implanted unilaterally into the carotid artery in 12 domestic pigs. Ultrasonography was used to test the proximal and distal anastomotic stoma morphology, diameters and blood velocities. A thrombosis instrument was used to examine the blood coagulation state. After seven days, the pigs were sacrificed and the implanted grafts were excised for general and histological analysis. Computational fluid dynamics was used to investigate the blood flow fields of the implanted grafts and to calculate parameters that might be indicative of thrombosis.

Results:

Thrombosis was detected in 10 of 12 (83.3%) implanted ePTFE grafts, 5 in uncoated grafts and 5 in anti-CD34-coated grafts. Endothelial cell coverage was observed in both uncoated and anti-CD34-coated grafts. No obvious abnormalities in anastomotic stoma or blood coagulation state were observed. Computer-based local hemodynamic simulation showed the low flexibility of synthetic ePTFE grafts caused obvious coarctation. Local wall pressure, velocity and wall shear stress were much higher than in the contralateral normal vessel.

Conclusions:

The patency of small-caliber ePTFE grafts for clinical use is impaired by early thrombosis due to mixed causes. Local hemodynamic disturbance was the most powerful predictor of early thrombosis. Decreasing local hemodynamic disturbance, improving the quality of anastomotic stoma, selecting reasonable anticoagulation strategies and promoting rapid endothelialization may increase the long-term patency of small-caliber vascular grafts.
Priorities for treatment, care and information if faced with serious illness: A comparative population-based survey in seven European countries
Authors: Higginson Irene J , Gomes Barbara , Calanzani Natalia , Gao Wei , Bausewein Claudia , Daveson Barbara A , Deliens Luc , Ferreira Pedro L , Toscani Franco , Gysels Marjolein , Ceulemans Lucas , Simon Steffen T , Cohen Joachim , Harding Richard ,   on behalf of Project PRISMA
Published: May 2013

Background:

Health-care costs are growing, with little population-based data about people’s priorities for end-of-life care, to guide service development and aid discussions.

Aim:

We examined variations in people’s priorities for treatment, care and information across seven European countries.

Design:

Telephone survey of a random sample of households; we asked respondents their priorities if ‘faced with a serious illness, like cancer, with limited time to live’ and used multivariable logistic regressions to identify associated factors.

Setting/participants:

Members of the general public aged ≥16 years residing in England, Flanders, Germany, Italy, the Netherlands, Portugal and Spain.

Results:

In total, 9344 individuals were interviewed. Most people chose ‘improve quality of life for the time they had left’, ranging from 57% (95% confidence interval: 55%–60%, Italy) to 81% (95% confidence interval: 79%–83%, Spain). Only 2% (95% confidence interval: 1%–3%, England) to 6% (95% confidence interval: 4%–7%, Flanders) said extending life was most important, and 15% (95% confidence interval: 13%–17%, Spain) to 40% (95% confidence interval: 37%–43%, Italy) said quality and extension were equally important. Prioritising quality of life was associated with higher education in all countries (odds ratio = 1.3 (Flanders) to 7.9 (Italy)), experience of caregiving or bereavement (England, Germany, Portugal), prioritising pain/symptom control over having a positive attitude and preferring death in a hospice/palliative care unit. Those prioritising extending life had the highest home death preference of all groups. Health status did not affect priorities.

Conclusions:

Across all countries, extending life was prioritised by a minority, regardless of health status. Treatment and care needs to be reoriented with patient education and palliative care becoming mainstream for serious conditions such as cancer.
Functional topography of serotonergic systems supports the Deakin/Graeff hypothesis of anxiety and affective disorders
Authors: Paul Evan D , Lowry Christopher A
Published: May 2013

Over 20 years ago, Deakin and Graeff hypothesized about the role of different serotonergic pathways in controlling the behavioral and physiologic responses to aversive stimuli, and how compromise of these pathways could lead to specific symptoms of anxiety and affective disorders. A growing body of evidence suggests these serotonergic pathways arise from topographically organized subpopulations of serotonergic neurons located in the dorsal and median raphe nuclei. We argue that serotonergic neurons in the dorsal/caudal parts of the dorsal raphe nucleus project to forebrain limbic regions involved in stress/conflict anxiety-related processes, which may be relevant for anxiety and affective disorders. Serotonergic neurons in the “lateral wings” of the dorsal raphe nucleus provide inhibitory control over structures controlling fight-or-flight responses. Dysfunction of this pathway could be relevant for panic disorder. Finally, serotonergic neurons in the median raphe nucleus, and the developmentally and functionally-related interfascicular part of the dorsal raphe nucleus, give rise to forebrain limbic projections that are involved in tolerance and coping with aversive stimuli, which could be important for affective disorders like depression. Elucidating the mechanisms through which stress activates these topographically and functionally distinct serotonergic pathways, and how dysfunction of these pathways leads to symptoms of neuropsychiatric disorders, may lead to the development of novel approaches to both the prevention and treatment of anxiety and affective disorders.
Impact of slice thickness on semi-automated measurements for volume and whole-tumor attenuation of colorectal hepatic metastases in multislice computed tomography
Authors: Rao Sheng-Xiang , Meng Tao , Zhang Li-Jun , Zeng Meng-Su
Published: May 2013

Background

Volumetric and whole-tumor attenuation assessment of tumor are of value in assessment of treatment.

Purpose

To assess the impact of slice thickness on semi-automatic analyses (volume, whole-tumor attenuation) for small colorectal hepatic metastases.

Material and Methods

Computed tomography (CT) data of patients with colorectal hepatic metastases at 1.5-, 3-, and 5-mm slice thickness were semi-automatically evaluated for volume and whole-tumor attenuation by two radiologists independently. Statistical analysis included paired samples t-test and concordance correlation coefficient (CCC) analysis according to the longest axial tumor diameter (10–20 mm, 20–30 mm, 30–40 mm).

Results

A total of 62 patients (32 men and 30 women) with 62 target tumors were included. The mean volume was significantly higher at 3- and 5-mm slice thicknesses in comparison with the reference (1.5 mm) for the target tumors between 10 mm and 20 mm ( P = 0.0295, CCC = 0.9394 for 3 mm; P = 0.0029, CCC = 0.5129 for 5 mm, respectively) and at 5 mm slice thickness for the target tumors between 20 mm and 30 mm ( P = 0.0071, CCC = 0.9102). For whole-tumor attenuation measurements, the significant difference was only seen at 5-mm slice thicknesses in comparison with the reference (1.5 mm) for the target tumors between 10 and 20 mm ( P = 0.0015, CCC = 0.9389).

Conclusion

Slice thickness of 1.5 mm might be suggested for semi-automated volumetric measurements, and slice thickness of no more than 3 mm for whole-tumor CT attenuation in hepatic metastasis between 10 mm and 20 mm.
The Riddle of Qohelet and Qohelet the Riddler
Authors: Ingram Doug
Published: May 2013

This article builds on the author's contention, expressed elsewhere, that Ecclesiastes is fundamentally ambiguous by design. This is done by examining the seven occurrences of the name ‘Qohelet’ or the title ‘the qohelet’ in the book. The article argues that ambiguity is a ‘deliberate didactic device’, employed by Qohelet, the teacher, to provoke his students to grapple with the meaning of his words, and to apply the strategies developed in relation to the ambiguities (including the riddles) of his words to the ambiguities of life in the world beyond the text. However, Qohelet is a character in the book and the author not only portrays him as a teacher who uses riddle and ambiguity, but also presents Qohelet himself as a riddle to be solved.
A case of cluster headache treated with rotigotine: Clinical and neurophysiological correlates
Authors: Di Lorenzo Cherubino , Coppola Gianluca , Pierelli Francesco
Published: May 2013

Background

Chronic cluster headache (CCH) is characterized by recurrent bouts of facial pain lasting up to 180 minutes in the absence of a long remission period.

Case

We report the case of a 43-year-old male patient with treatment-resistant CCH, who improved with administration of transdermal rotigotine. We also evaluated the nociceptive blink reflex habituation that was reduced before the treatment (as is usual in CH patients) and normalized by transdermal rotigotine.

Conclusions

We suggest that rotigotine could represent a further therapeutic option in the treatment of drug-resistant CCH.
A Comparative Study of Meniscectomy and Nonoperative Treatment for Degenerative Horizontal Tears of the Medial Meniscus
Authors: Yim Ji-Hyeon , Seon Jong-Keun , Song Eun-Kyoo , Choi Jun-Ik , Kim Min-Cheol , Lee Keun-Bae , Seo Hyoung-Yeon
Published: May 2013

Background:

It is still debated whether a degenerative horizontal tear of the medial meniscus should be treated with surgery.

Hypothesis:

The clinical outcomes of arthroscopic meniscectomy will be better than those of nonoperative treatment for a degenerative horizontal tear of the medial meniscus.

Study Design:

Randomized controlled trial; Level of evidence, 1.

Methods:

A total of 102 patients with knee pain and a degenerative horizontal tear of the posterior horn of the medial meniscus on magnetic resonance imaging were included in this study between January 2007 and July 2009. The study included 81 female and 21 male patients with an average age of 53.8 years (range, 43-62 years). Fifty patients underwent arthroscopic meniscectomy (meniscectomy group), and 52 patients underwent nonoperative treatment with strengthening exercises (nonoperative group). Functional outcomes were compared using a visual analog scale (VAS) for pain, Lysholm knee score, Tegner activity scale, and patient subjective knee pain and satisfaction. Radiological evaluations were performed using the Kellgren-Lawrence classification to evaluate osteoarthritic changes.

Results:

In terms of clinical outcomes, meniscectomy did not provide better functional improvement than nonoperative treatment. At the final follow-up, the average VAS scores were 1.8 (range, 1-5) in the meniscectomy group and 1.7 (range, 1-4) in the nonoperative group ( P = .675). The average Lysholm knee scores at 2-year follow-up were 83.2 (range, 52-100) and 84.3 (range, 58-100) in the meniscectomy and nonoperative groups, respectively ( P = .237). In addition, the average Tegner activity scale and subjective satisfaction scores were not significantly different between the 2 groups. Although most patients initially had intense knee pain with mechanical symptoms, both groups reported a relief in knee pain, improved knee function, and a high level of satisfaction with treatment ( P < .05 for all values). Two patients in the meniscectomy group and 3 in the nonoperative group with Kellgren-Lawrence grade 1 progressed to grade 2 at the 2-year follow-up.

Conclusion:

There were no significant differences between arthroscopic meniscectomy and nonoperative management with strengthening exercises in terms of relief in knee pain, improved knee function, or increased satisfaction in patients after 2 years of follow-up.
The effect of occupational lead exposure on lipid peroxidation, protein carbonylation, and plasma viscosity
Authors: Kasperczyk Sławomir , Słowińska-Łożyńska Ludmiła , Kasperczyk Aleksandra , Wielkoszyński Tomasz , Birkner Ewa
Published: May 2013

The aim of the study was to investigate the influence of occupational lead (Pb) exposure on lipid peroxidation, protein carbonylation, and plasma viscosity in workers. The examined group included 283 healthy male employees of manufacturing facilities using zinc and Pb. The mean blood concentrations of Pb and zinc protoporphyrin as well as the mean urine δ-aminolevulinic acid levels were used as markers of exposure for the examined group. Taking into account the obtained mean values of blood lead level, the examined group was divided into three subgroups. When comparing the control group with the subgroups, Pb exposure markers were significantly elevated in all the three subgroups. Concentrations of conjugated dienes (CD), lipid hydroperoxides, malondialdehyde (MDA), and protein carbonyl groups were also significantly increased. Conversely, the levels of total protein and protein sulfhydryls were significantly decreased in the subgroups compared with the controls. The plasma viscosity was significantly elevated in the subgroups. A dose–response between Pb levels and plasma viscosity was not observed. Pb supposedly elevates MDA and CD in a dose-dependent manner. In conclusion, occupational Pb exposure induces oxidative stress that results in lipid and protein damage. Moreover, Pb-induced oxidative stress is likely the primary factor that elevates plasma viscosity, despite decreased protein levels.
Trapping tetracycline-loaded nanoparticles into polycaprolactone fiber networks for periodontal regeneration therapy
Authors: Khodir WK Wan Abdul , Guarino V , Alvarez-Perez MA , Cafiero C , Ambrosio L
Published: May 2013

The controlled delivery of antibiotics, anti-inflammatory agents, or chemotherapeutic agents to the periodontal site is a recognized strategy to improve the efficiency of regenerative processes of hard tissues. A novel approach based on the trapping of tetracycline hydrochloride–loaded particles in polycaprolactone nanofibers was used to guide the regeneration processes of periodontal tissue at the gum interface. Chitosan nanoparticles loaded with different levels of tetracycline hydrochloride (up to 5% wt) were prepared by solution nebulization induced by electrical forces (i.e. electrospraying). The fine tuning of process parameters allows to obtain nanoparticles with tailored sizes ranging from 0.485 ± 0.147 µm to 0.639 ± 0.154 µm. The tetracycline hydrochloride release profile had a predominant burst effect for the first 70% of release followed by a relatively slow release over 24 h, which is promising for oral drug delivery. We also demonstrated that trapping tetracycline hydrochloride–loaded particles with submicrometer diameters into a polycaprolactone fiber network contributed to slowing the release of tetracycline hydrochloride from the nanoparticles, thus providing a more prolonged release in the periodontal pocket during clinical therapy. Preliminary studies on human mesenchymal stem cells confirm the viability of cells up to 5 days after culture, and thereby, validate the use of nanoparticle-/nanofiber-integrated systems in periodontal therapies.
Avidin-conjugated polymers with monobiotinylated antibody fragments: A new strategy for the noncovalent attachment of recombinant proteins for polymer therapeutics
Authors: Laga Richard , Pola Robert , Ulbrich Karel , Horřejší Magda , Sieglová Irena , Král Vlastimil , Fábry Milan , Pechar Michal
Published: May 2013

The high affinity and specificity between avidin and biotin were employed to bind a recombinant single-chain antibody fragment to synthetic hydrophilic polymer drug carriers. Two semitelechelic polymers, based on poly(ethylene glycol) and poly[ N-(2-hydroxypropyl)methacrylamide], each containing a single thiol end group, were conjugated to dithiopyridyl-modified avidin. The biotinylated recombinant single-chain antibody fragment of the M75 antibody was then noncovalently bound to the polymer-avidin conjugates. The recombinant protein was chosen as a targeting ligand against carbonic anhydrase IX, a marker overexpressed by tumor cells of various human carcinomas. The antigen-binding affinity of the polymer–single-chain antibody fragment complex was confirmed by enzyme-linked immuno sorbent assay (ELISA). This approach provides an original, nondestructive way of preparing supramolecular systems intended for targeted delivery of therapeutics utilizing modern chemical procedures, including reversible addition–fragmentation chain-transfer polymerization and recombinant DNA techniques.
Social Media and Campaign 2012
Authors: Gulati Girish J. , Williams Christine B.
Published: May 2013

Diffusion of innovation theory is used to explain adoption of Facebook in the 2012 campaigns for the U.S. Congress and to identify characteristics that differentiate the small subset of candidates who did not create a Facebook presence from the large majority who did. Models of Facebook adoption for House candidates reveal that there are no differences between Republicans and Democrats. Nonadopters are significantly more likely to be challengers or open-seat candidates, poorly financed candidates, candidates in noncompetitive races, and older. Among nonincumbents, Republicans, and candidates from Republican-oriented districts are more likely to adopt. This study serves as one of the first examinations of social media adoption by congressional candidates in the 2012 elections and discusses relevant developments and trends in adoption since Facebook’s introduction in 2006.
‘Commodifying institutions’: vertical disintegration and institutional change in German labour relations
Authors: Holst Hajo
Published: May 2013

The article analyses the impact of vertical disintegration on German labour relations. Previous research argued that the proliferation of outsourcing, divestment and non-standard employment results in a ‘dualism’ between a core of secure workplaces and a growing fringe of precarious jobs. Evidence from two key sectors, metalworking and telecommunications, however, suggest that this clear-cut division is replaced by a fragmented landscape of labour relations. In terms of institutional change, the analysis reveals a specific form of incremental transformative change, namely a shift in the meaning of formally stable legal-political institutions. Even in the allegedly stable core areas, the institutions of labour relations are gradually transformed from market-constituting institutions to market-dependent variables. Vertical disintegration plays an important role in this process of institutional commodification. It not only moves the core–periphery boundary; it is also deployed to subjugate collective bargaining, workplace co-determination and the utilization of labour law to firm-level economic calculations.
The effects of bidirectional evolutionary structural optimization parameters on an industrial designed component for additive manufacture
Authors: Aremu Adedeji , Ashcroft Ian , Wildman Ricky , Hague Richard , Tuck Chris , Brackett David
Published: May 2013

An assessment of the effect of topology optimization design parameters on the performance of an additively manufactured part has been performed. The dependence of the output from a topology optimization involving an aerospace component on the topology optimization control parameters, evolution rate and filter radius was determined. The converged strain energy was found to depend quadratically on the filter radius while the number of iterations required to achieve a solution was broadly related to the evolution rate. These findings demonstrate the potential for significant design efficiencies when manufacturing using additive manufacturing approaches but also the need to be aware of the sensitivity of the bidirectional evolutionary structural optimization optimized design on the selected optimization parameters. This sensitivity can potentially be used advantageously to steer the solution to an optima with features suitable to a particular manufacturing method such as additive manufacturing.
Effect of cutting speed on tool life in ultrasonic-assisted milling process
Authors: Janghorbanian Javad , Razfar Mohammad R , Abootorabi Zarchi Mohammad M
Published: May 2013

Machining processes are inherently involved with tool wear, which is an influential factor in cutting forces, surface roughness, and machining costs. In conventional machining of some materials, there are some limitations regarding rapid wear of tool and large machining forces. As a result, new machining techniques have been developed in recent years, among which is the ultrasonic-assisted machining. This machining method is a combination of ultrasonic vibrations with conventional machining process. The goal of this article is to compare the tool life in ultrasonic-assisted milling and conventional milling processes. In experimental tests, one-dimensional ultrasonic vibrations have been applied on workpiece in the feed direction of tool. By varying spindle speed, the width of flank wear land of cutting tool has been obtained in ultrasonic-assisted milling and conventional milling processes, and the results are compared with each other. Due to tool rotation, the direction of workpiece vibrations with respect to edge of cutting tool varies in time. Consequently, there is the possibility of improper and uncontrolled contacts between tool and workpiece. In order to examine this issue, the relative speed of workpiece in normal direction of tool flank surface has been obtained analytically, and the results have been used in explaining the experimental observations. The experimental results have shown that in spindle speeds of n = 500, 1000, and 2000 r/min, tool life in ultrasonic-assisted milling process is less than in conventional milling process; however, for spindle speed of n = 3150 r/min, due to change in tool wear mechanism and decrease of relative speed of workpiece in normal direction of tool flank surface, tool life in ultrasonic-assisted milling process becomes larger than that in conventional milling process.
Integrating the Taguchi method and the multiattribute decision-making method to optimize the surface mount technology solder paste printing thickness process
Authors: Wang Shen-Tsu
Published: May 2013

In order to meet the demand for the current consumer electronic products, the improvement of the surface mount technology is an important trend. This study used the Taguchi method to develop different level schemes of the surface mount technology solder paste printing process parameter in order to obtain the conditions of parameter combinations of the surface mount technology solder paste printing process parameter. However, the Taguchi method of experimental configuration requires multiple trials to obtain the surface mount technology solder paste printing process parameter, which may require considerable cost and time. Therefore, this study attempted to use two multiattribute decision-making methods, gray relational analysis, and technique for order preference by similarity to ideal solution evaluating method, in order to determine a group of optimal experimental schemes from among the established multiple experimental schemes using the Taguchi method. This study also used the process capability parameter to verify the research methods. The experimental results showed that surface mount technology solder paste printing thickness process capability ( Cpk) value has improved from 0.59 to 1.53, which could improve product quality. The Taguchi and two multiattribute decision-making methods have proven that the model can effectively obtain the surface mount technology solder paste printing thickness process parameter.
Tensor product model transformation-based control design for force reflecting tele-grasping under time delay
Authors: Galambos Péter , Baranyi Péter , Arz Gusztáv
Published: May 2013

The improvement of direct human–robot physical interaction has recently become one of the strongest motivation factors in robotics research. Impedance/admittance control methods are key technologies in several directions of advanced robotics such as dexterous manipulation, haptics and telemanipulation. In this paper, we propose a control scheme and a design technique for stabilising shared impedance/admittance-based bilateral telemanipulation under varying time delay. The proposed scheme introduces delay-adaptive non-linear damping to stabilise the impedance model. A modified version of the tensor product model transformation is applied to determine the tensor product type polytopic linear parameter varying (LPV) representation of the impedance controlled interaction model, such that the value of the actual time delay becomes an external parameter rather than an inherent property of the system. The main benefit of the proposed approach is that the model form it produces is amenable to the immediate application of modern, linear matrix inequality (LMI)-based multi-objective synthesis methods. The viability of the proposed methodology is demonstrated through a single DoF force reflecting tele-grasping application. The results are also confirmed through laboratory experiments which help to further highlight the perspectives of this novel approach.
Analysis of train/turnout vertical interaction using a fast numerical model and validation of that model
Authors: Wan Chang , Markine Valeri L , Shevtsov Ivan Y
Published: May 2013

A two-dimensional (2D) finite element model has been developed for simulation and analysis of train/turnout vertical dynamic interactions at a common crossing. The model has been validated through field measurements and simulation results obtained using a three-dimensional (3D) multi-body system (MBS) model. The dynamic behaviour of three turnouts on the Dutch railway network was simulated using the 2D model. The simulation results were compared with measured data collected from the instrumented crossings containing corresponding turnouts. It was observed that the values of the vertical acceleration of the crossing nose obtained from the simulations were in good agreement with the measured values. The 2D model was verified by adapting the more intricate 3D MBS model established in the VI-Rail software. The vertical geometry of the rail used in the 2D model was obtained using the wheel trajectory from the 3D model. It was observed that the dynamic wheel forces in the two models were close to one another. From these results it was concluded that the 2D model is able to simulate train/turnout interactions with a good accuracy and thus it can be used instead of complex time-consuming numerical simulations.