bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of genes involved in low aminoglycoside-induced SOS response inVibrio cholerae: a role for transcription stalling and Mfd helicase
Authors: Baharoglu Zeynep , Babosan Anamaria , Mazel Didier
Published: December 2013

Sub-inhibitory concentrations (sub-MIC) of antibiotics play a very important role in selection and development of resistances. Unlike Escherichia coli, Vibrio cholerae induces its SOS response in presence of sub-MIC aminoglycosides. A role for oxidized guanine residues was observed, but the mechanisms of this induction remained unclear. To select for V. cholerae mutants that do not induce low aminoglycoside-mediated SOS induction, we developed a genetic screen that renders induction of SOS lethal. We identified genes involved in this pathway using two strategies, inactivation by transposition and gene overexpression. Interestingly, we obtained mutants inactivated for the expression of proteins known to destabilize the RNA polymerase complex. Reconstruction of the corresponding mutants confirmed their specific involvement in induction of SOS by low aminoglycoside concentrations. We propose that DNA lesions formed on aminoglycoside treatment are repaired through the formation of single-stranded DNA intermediates, inducing SOS. Inactivation of functions that dislodge RNA polymerase leads to prolonged stalling on these lesions, which hampers SOS induction and repair and reduces viability under antibiotic stress. The importance of these mechanisms is illustrated by a reduction of aminoglycoside sub-MIC. Our results point to a central role for transcription blocking at DNA lesions in SOS induction, so far underestimated.
Ribosome profiling reveals post-transcriptional buffering of divergent gene expression in yeast
Authors: McManus C. Joel , May Gemma E. , Spealman Pieter , Shteyman Alan
Published: December 2013

Understanding the patterns and causes of phenotypic divergence is a central goal in evolutionary biology. Much work has shown that mRNA abundance is highly variable between closely related species. However, the extent and mechanisms of post-transcriptional gene regulatory evolution are largely unknown. Here we used ribosome profiling to compare transcript abundance and translation efficiency in two closely related yeast species (S. cerevisiaeandS. paradoxus). By comparing translation regulatory divergence to interspecies differences in mRNA sequence features, we show that differences in transcript leaders and codon bias substantially contribute to divergent translation. Globally, we find that translation regulatory divergence often buffers species differences in mRNA abundance, such that ribosome occupancy is more conserved than transcript abundance. We used allele-specific ribosome profiling in interspecies hybrids to compare the relative contributions ofcis- andtrans-regulatory divergence to species differences in mRNA abundance and translation efficiency. The mode of gene regulatory divergence differs for these processes, astrans-regulatory changes play a greater role in divergent mRNA abundance than in divergent translation efficiency. Strikingly, most genes with aberrant transcript abundance in F1 hybrids (either over- or underexpressed compared to both parent species) did not exhibit aberrant ribosome occupancy. Our results show that interspecies differences in translation contribute substantially to the evolution of gene expression. Compensatory differences in transcript abundance and translation efficiency may increase the robustness of gene regulation.
Leadership, a key element of quality improvement in healthcare. Results from a literature review of “Lean Healthcare” and the Productive Ward
Authors: White Mark , Wells John , Butterworth Tony
Published: December 2013

Purpose

– This paper reviews the Lean Healthcare and Productive Ward: releasing time to care (RTC) literature and extracts the reported effects and impacts experienced by employees who implement it. The purpose of this paper is to identify and investigate the strength of the connection between the two models and explores the implications for leadership and implementation.

Design/methodology/approach

– This study reviewed the Lean Healthcare and Productive Ward: RTC literature using strict systematic inclusion criteria. A qualitative content analysis was used to identify key characteristics of reported employee experience, effect or impact. Themes and categories were ranked by the number of citations and presented.

Findings

– This study outlines the similar employee effects and impacts that exist between Lean-type improvement initiatives and the Productive Ward: RTC programme. It discusses the three top themes of: Empowerment, Leadership and Engagement and explores the opportunities for leadership. It also identifies one key difference between the two initiatives, the socio-cultural effect and impact which is strongly reported with Lean-type improvement initiatives. The socio-cultural element is discussed and presented as one of the fundamental aspects of Lean and the original Toyota production system.

Originality/value

– This study brings new insights for leaders involved in Lean-type improvement initiatives which are currently being imported into healthcare and provides a comprehensive list of reported employee impacts and effects of value to healthcare leaders attempting to establish an environment and culture of improvement.
What is happening to leadership in health care?
Authors: Iles Valerie
Published: December 2013

Purpose

– The purpose of this paper is to re-examine the challenges facing leaders in health care, to explore the impact of these on the choices available to healthcare leaders, and to re-visit the nature of leadership in general. It identifies a distinction between care that is a set of auditable transactions and care that is also a covenant, and suggests that leadership too can be practised in these distinctively different ways. It draws on a three year learning set of senior practitioners in the NHS in England.

Design/methodology/approach

– This paper draws on the authors own observations over 25 years of educating and developing clinical leaders, and also on the insights of a learning set of senior NHS practitioners over a three period.

Findings

– The paper provides empirical insights about how both health care and leadership have changed over the last 30 years, and proposes that treating either of them as a set of auditable transactions in a market place results in dissatisfied leaders as well as practitioners, and that a covenant of both care and leadership needs to be understood and established.

Research limitations/implications

– Observations have been limited to the NHS in the UK although there are indications that the issues are of wider applicability.

Practical implications

– The paper includes implications for the behaviours of those leading health care organisations, those being led, and those influencing the context.

Originality/value

– This paper challenges prevailing definitions of leadership and prevailing explanations for difficulties in health care organisations.
On the almost inconceivable misunderstandings concerning the subject of value‐free social science
Authors: Black Donald
Published: December 2013

A value judgment says what is good or bad, and value‐free social science simply means social science free of value judgments. Yet many sociologists regard value‐free social science as undesirable or impossible and readily make value judgments in the name of sociology. Often they display confusion about such matters as the meaning of value‐free social science, value judgments internal and external to social science, value judgments as a subject of social science, the relevance of objectivity for value‐free social science, and the difference between the human significance of social science and value‐free social science. But why so many sociologists are so value‐involved – and generally so unscientific – is sociologically understandable: The closest and most distant subjects attract the least scientific ideas. And during the past century sociologists have become increasingly close to their human subject. The debate about value‐free social science is also part of an epistemological counterrevolution of humanists (including many sociologists) against the more scientific social scientists who invaded and threatened to expropriate the human subject during the past century.
Theoretical and experimental investigations of the performance of keyword auction mechanisms
Authors: Fukuda Emiko , Kamijo Yoshio , Takeuchi Ai , Masui Michiharu , Funaki Yukihiko
Published: December 2013

Two keyword auction mechanisms, the Generalized Second‐Price auction (GSP) and the Vickrey‐Clarke‐Groves mechanism (VCG), were compared theoretically and experimentally. The former is widely used in practice; the latter is not, but it has a dominant strategy equilibrium where all participants bid their true values. In the theoretical investigation, by applying the “locally envy‐free Nash equilibrium” to the VCG, we found that the allocations are efficient and that upper and lower bounds of the auctioneer's revenue coincide in the two mechanisms. A laboratory experiment, in which the revenues and efficiencies were similar in both mechanisms, supported this result.
Commentary on the Interactions of HIV and Alcohol in the Central Nervous System
Authors: Nair Madhavan P. , Agudelo Marisela
Published: December 2013

This commentary is to highlight the relevance and public interest of the review published by Silverstein and Kumar, which focuses on the mechanisms by which alcohol and HIV‐1 infection cause increased in central nervous system (CNS) damage. The overall review is based on previous literature with cell culture systems and animal models that have demonstrated that exposure to alcohol and HIV infection or HIV viral proteins result in synergistic up‐regulation of pro‐inflammatory cytokines and oxidative stress. The authors discuss the effects of alcohol on cells in the CNS, followed by a brief discussion on the impact of HIV‐1 and HIV proteins on the CNS, and the final section focuses on the combined effects of HIV and alcohol on the CNS as determined by in vitro, in vivo, and clinical studies.
High hopes for CB2 receptors in neurogenesis
Authors: Downer Eric J
Published: December 2013

During life, new neurons are continually added to hippocampal circuitry, with evidence suggesting that these adult‐born neurons are functionally linked to cognition and emotion. The mammalian brain contains actively dividing neural stem cells in discrete regions, including the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus. Once mature, these neurons integrate into neuronal networks, forming synaptic connections with interneurons, mossy cells and CA3 pyramidal cells

Linked Article

This article is a commentary on Avraham et al., pp. 468–479 of volume 171 issue 2. To view this paper visit http://dx.doi.org/10.1111/bph.12478
Factors associated with dental caries in Brazilian children: a multilevel approach
Authors: Martins MT , Sardenberg F , Abreu MH , Vale MP , Paiva SM , Pordeus IA
Published: December 2013

Objectives

The aims of the present study were to assess caries experience among Brazilian children aged eight to 10 years and determine social factors of this disease, through a multilevel approach.

Methods

This is a cross‐sectional study in which a representative sample of 1204 eight‐to‐ten‐year‐old children were randomly selected from 19 public and private schools in the city of Belo Horizonte, Brazil. After formal authorization from the parents, the children were clinically examined at school by two calibrated examiners (Kappa=0.78). Individual socioeconomic status was determined using household income, number of residents in the home and parents'/caregivers' schooling. The social vulnerability index and type of school were used as contextual variables. The outcome variables were severity score of dental caries in permanent teeth (DMFT index), dental caries experience in permanent teeth (DMFT = 0 or ≠ 0), severity score of dental caries in primary teeth (dmft index) and dental caries experience in primary teeth (dmft = 0 or ≠ 0).

Results

The minority of children (37.2%) had dental caries experience. Chi‐squared and Mann–Whitney tests showed that age, parents'/caregivers' schooling, household income and type of school were associated with dental caries experience in permanent and primary teeth (P < 0.05). Mann–Whitney, Kruskal–Wallis tests and Spearman correlation coefficient showed that age, parents'/caregivers' schooling, household income, and type of school were associated with severity score of dental caries in permanent and primary teeth (P < 0.05). In multilevel approach, the individual variables, age and household income demonstrated association with dental caries experience and with severity score of dental caries in primary teeth (P < 0.05). Type of school was also associated with dental caries experience and with severity score of dental caries in these teeth (P < 0.05).

In the Poisson multilevel approach, the analysis of the final estimation of variance components of the null model revealed a significant difference among the 19 schools with regard to severity score of dental caries in permanent teeth too (P < 0.001). Younger children and attending private schools showed lower severity score of dental caries in permanent teeth.

Conclusion

Dental caries experience and severity score of dental caries in primary teeth was influenced by age, household income, and the type of school The dental caries experience in permanent teeth was influenced by age, parents'/caregivers' schooling, household income, and type of school, whereas the severity score of dental caries in permanent teeth was influenced by age and type of school.
Reactive eccrine syringofibroadenomatosis secondary to primary cutaneous amyloidosis: a novel association
Authors: Saggini Andrea , Mully Thaddeus
Published: December 2013

We report the unprecedented case of reactive eccrine syringofibroadenoma (ESFA) secondary to primary cutaneous amyloidosis. A 62‐year‐old woman of Asian ethnicity presented with a pruritic rash on the back of long‐standing duration. Physical examination revealed diffuse hyperpigmentation localized to the interscapular region; there were a multitude of hyperpigmented macules merged in a rippled pattern intermixed with scattered papules and cobblestone‐like areas. A punch biopsy from a papule was taken. Histopathological examination revealed a network of epithelial strands and cords hanging from the epidermis and harboring foci of ductal differentiation. Eosinophilic collections of amorphous material were found between the epithelial strands, obscuring the superficial dermis. The microscopic picture was consistent with primary cutaneous amyloidosis associated with reactive ESFA. Results of histochemical and immunohistochemical staining confirmed the diagnosis. We speculate that pathogenetic mechanisms intrinsic to primary cutaneous amyloidosis, in addition to unknown genetic factors, resulted in clinical changes of lichen amyloidosus associated with an abnormal hyperplastic epithelial response with histopathological features of ESFA rather than the common epidermal change of acanthosis and hyperkeratosis.
Levodopa/carbidopa intestinal gel infusion in advanced Parkinson's disease: a 7‐year experience
Authors: Zibetti M. , Merola A. , Artusi C. A. , Rizzi L. , Angrisano S. , Reggio D. , De Angelis C. , Rizzone M. , Lopiano L.
Published: December 2013

Background and purpose

Levodopa/carbidopa intestinal gel (LCIG) infusion is nowadays becoming an established therapeutic option for advanced Parkinson's disease (PD) patients with fluctuating symptoms unresponsive to conventional oral treatment. As the implementation of LCIG therapy is increasing, there is a need for safety and efficacy data from current clinical practice.

Methods

All PD patients treated with LCIG at our centre over a 7‐year period were analysed to determine the duration of treatment, retention rate, reasons for discontinuation, LCIG efficacy in motor complications, modifications of concomitant therapy and adverse events.

Results

Of the 59 patients, seven subjects (12%) died of causes unrelated to LCIG infusion and 11 patients (19%) discontinued therapy prior to the cut‐off date. Duodopa improved motor complications and over 90% of patients reported an improvement in their quality of life, autonomy and clinical global status. The most common adverse events were dislocation and kinking of the intestinal tube.

Conclusions

LCIG infusion is effective for the long‐term treatment of advanced PD patients and exerts a positive and clinically significant effect on motor complications with a relatively low dropout rate.
Anticardiolipin antibodies are associated with cognitive dysfunction in stroke‐free individuals
Authors: Homayoon N. , Schwingenschuh P. , Hofer E. , Katschnig‐Winter P. , Schmidt R.
Published: December 2013

Background and purpose

The presence of anticardiolipin antibodies (aCLs) has been associated with vascular occlusive events. The role of aCLs as a risk factor for stroke has been a matter of debate, and scarce information exists on the relationship between aCLs and other cerebral disorders. Reports exist for seizures, chorea and subtle cognitive dysfunction. The association between aCLs and cognition was further explored and the relationship between aCL titres and brain magnetic resonance imaging (MRI) findings was evaluated in a large cohort of community‐dwelling individuals.

Methods

The study cohort was drawn from the Austrian Stroke Prevention Study. A total of 1895 subjects had a complete risk factor assessment and measurement of aCL titres in serum. Participants were classified as aCL positive if either the immunoglobulin G (IgG) or IgM aCL titres were elevated (IgG > 21 U/ml, IgM > 12 U/ml). All subjects were also categorized based on the quartile distribution of IgG and IgM isotype titres. All underwent cognitive testing by the Mini Mental State Examination (MMSE) and a random sample of 947 participants also underwent brain MRI.

Results

aCL positive participants performed worse on the MMSE. IgG but not IgM isotype titres related to worse performance on the MMSE. No significant association existed with vascular brain abnormalities including lacunes, cortical infarcts and white matter lesions.

Conclusions

These data support the view that in normal elderly persons increasing IgG aCL titres relate to global cognitive dysfunction. It is unlikely that structural brain lesions are responsible for this finding.
Septic funiculitis caused byStreptococcus equisubspeciesequiinfection with associated immune‐mediated haemolytic anaemia
Authors: Caniglia C. J. , Davis J. L. , Schott H. C. , Brakenhoff J. E.
Published: December 2013

A 2‐year‐oldQuarterHorse gelding presented for anaemia, icterus, depression and intermittent colic 2 weeks after routine castration. Bilateral septic funiculitis withStreptoccocus equissp.equiwith secondary immune‐mediated haemolytic anaemia were diagnosed. A blood transfusion was required to facilitate general anaesthesia for surgical excision of the septic funiculitis. Antibiotic therapy was provided initially with chloramphenicol and later enrofloxacin. Immunosuppressive therapy was provided with dexamethasone and later azathioprine. The horse responded well to treatment and was discharged 8 weeks after presentation.Streptococcus equissp.equishould be considered in cases with septic funiculitis and the potential for a secondary immune‐mediated haemolytic anaemia exists with this bacterial species.
Omentin serum levels and omentin gene Val109Asp polymorphism in patients with psoriasis
Authors: Turan Hakan , Yaykasli Kursat Oguz , Soguktas Hatice , Yaykasli Emine , Aliagaoglu Cihangir , Erdem Teoman , Karkucak Mutlu , Kaya Ertugrul , Ucgun Taner , Bahadir Anzel
Published: December 2013

Background

Psoriasis is a chronic inflammatory disease of uncertain pathogenesis. Omentin is a new adipokine with anti‐inflammatory properties; however, the relationship between psoriasis and omentin has not been fully established yet.

Objectives

This study was designed to evaluate the relationship between psoriasis and omentin serum levels and Val109Asp polymorphism in exon 4 of the omentin gene.

Methods

Forty‐nine patients with plaque‐type psoriasis and 39 healthy subjects were included in the study. Omentin concentrations were determined by using enzyme‐linked immunosorbent assay. Val109Asp polymorphism in exon 4 of the omentin gene was assessed by the polymerase chain reaction–restriction fragment length polymorphism method. Genotypes were determined according to the bands formed in agarose electrophoresis gels. In the statistical analysis, the level of significance was set at P < 0.05.

Results

The serum omentin levels of the patients with psoriasis (354.2 ± 152.0) were found to be significantly lower than those in the control group (488.7 ± 190.3) (P = 0.001). A moderate level negative correlation was determined between serum omentin level and body mass index and waist circumference. No significant differences were observed between the patient and control groups in terms of the genotype and allele frequency of Val109Asp polymorphism in exon 4 of the omentin gene (P > 0.05).

Conclusions

Omentin serum levels were determined to be low in patients with psoriasis. No significant difference was found regarding Val109Asp polymorphism of the omentin gene. To the best of our knowledge, our study is the first clinical study to examine the relationship between psoriasis and omentin in terms of serum and genomic levels.
Spouses’ reflections on Implantable Cardioverter Defibrillator treatment with focus on the future and the end‐of‐life: a qualitative content analysis
Authors: Fluur Christina , Bolse Kärstin , Strömberg Anna , Thylén Ingela
Published: December 2013

Aim

To explore future reflections of spouses living with an implantable cardioverter defibrillator recipient with focus on the end‐of‐life phase in an anticipated palliative phase.

Background

A history of or risk for life‐threatening arrhythmias may require an implantable cardioverter defibrillator. Despite the life‐saving capacity of the device, eventually life will come to an end. As discussion about preferences of shock therapy at end‐of‐life phase seldom takes place in advance, the implantable cardioverter defibrillator recipients may face defibrillating shocks in the final weeks of their lives, adding to stress and anxiety in patients and their families.

Design

Qualitative study with in‐depth interviews analysed with a content analysis.

Methods

Interviews were performed with 18 spouses of medically stable implantable cardioverter defibrillator recipients during 2011–2012.

Results

The spouses described how they dealt with changes in life and an uncertain future following the implantable cardioverter defibrillator implantation. Six subcategories conceptualized the spouses’ concerns: Aspiring for involvement; Managing an altered relationship; Being attentive to warning signs; Worries for deterioration in the partner's health; Waiting for the defibrillating shock; and Death is veiled in silence.

Conclusion

Despite the partner's serious state of health; terminal illness or death and the role of the device was seldom discussed with healthcare professionals or the implantable cardioverter defibrillator recipient. Open and honest communication was requested as important to support coping with an unpredictable life situation and to reduce worries and uncertainty about the future and end‐of‐life.
A Path to a Public–Private Partnership: Commercial Logistics Concepts Applied to Disaster Response
Authors: David Swanson R. , Smith Ronn J.
Published: December 2013

This paper initiates an exploratory investigation with the aim of providing a better understanding of the applicability of several commercial logistics processes to humanitarian logistics. The paper begins with background information, including humanitarian logistics literature and then summarizes current government agencies' and nongovernmental organizations' policies. Stakeholder theory is used to explore the motivations of commercial organizations to participate in humanitarian logistics operations. Next, the adequacy of emergency management policy is evaluated and four commercial logistics frameworks are analyzed for application to immediate disaster response. The analysis includes ratings of the frameworks and open‐ended comments from a sample of logistics experts. Findings provide guidance to the implementation of commercial logistics processes to disaster response efforts.
Assessing Mobility Competences of Children With Intellectual Disabilities: Development and Results of the Mobility Assessment Schedule
Authors: Kvas Štefan , Stöppler Reinhilde , Haveman Meindert , Tillmann Vera
Published: December 2013

This article describes the aims, development, and testing of the Mobility Assessment Schedule (MAS), an instrument assessing the ability of students with intellectual disability (ID), to function effectively as pedestrians in normal traffic. The MAS provides information about individual mobility skills of school‐age children with ID and measures the child's traffic skills congruent with safely and independently functioning in traffic situations. Mobility skills are measured in eight areas: visual perception, auditory perception, reaction, memory, attention, motor skills, social skills, and communication. The MAS was tested with 128 students at one school for children with ID in Germany. The internal consistencies of the scale and subscales were reasonable to good. Baseline results showed that the students already possessed—even before mobility training—many skills that are necessary for participation in traffic situations. The MAS is applicable and valid to assess traffic functioning skills of children with ID and can be an important tool for mobility training because it delivers information on various skills, which are necessary to function independently in traffic situations. This inventory can be part of the school's individual educational plans.
A Field Study of the Presumptively Biased: Is There Empirical Support for Excluding Convicted Felons from Jury Service?
Authors: Binnall James M.
Published: December 2013

In the United States, a vast majority of jurisdictions statutorily exclude convicted felons from jury service. Justifying these exclusions, lawmakers and courts often cite the inherent bias rationale, which holds that convicted felons harbor a prodefense/antiprosecution pretrial bias that would jeopardize the impartiality of the jury process. The inherent bias rationale has never been the subject of empirical analysis. Instead, authorities seemingly accept the logic of the rationale unconditionally. This study (1) explores the prevalence, strength, and direction of convicted felons' pretrial biases; (2) compares the group‐level pretrial biases of convicted felons, nonfelon eligible jurors, and nonfelon law students; and (3) examines if and how a felony conviction shapes pretrial biases. The results of this study indicate that a majority of convicted felons harbor a prodefense/antiprosecution bias and, in this way, differ from eligible jurors generally. Yet, the results of this study also show that many convicted felons are neutral or harbor a proprosecution pretrial bias, and that the strength and direction of convicted felons' group‐level pretrial biases are similar to those of other groups of nonfelon jurors. In sum, this study suggests that while felon jury exclusion does not offend applicable constitutional standards, it is an imprecise and perhaps unnecessary practice that may come at substantial costs.
Significance of serum and hepatic microRNA‐122 levels in patients with non‐alcoholic fatty liver disease
Authors: Miyaaki Hisamitsu , Ichikawa Tatsuki , Kamo Yasuhiro , Taura Naota , Honda Takuya , Shibata Hidetaka , Milazzo Maddalena , Fornari Francesca , Gramantieri Laura , Bolondi Luigi , Nakao Kazuhiko
Published: December 2013

Background & Aims

Non‐alcoholic fatty liver disease (NAFLD) is believed to be a type of metabolic syndrome. MicroRNA‐122 (miR‐122) is the most abundant microRNA in the liver and is an important factor for the metabolism of glucose and lipids. In the present study, we examined the correlation between the hepatic and serum miR‐122 expression levels and the clinicopathological factors of patients with NAFLD.

Methods

We extracted the total RNA, along with preserved miRNAs, from liver biopsy samples of 67 patients with NAFLD. In 52 of these 67 patients, the total RNA was extracted from serum. The miR‐122 that was obtained by quantitative reverse transcription‐polymerase chain reaction was quantified using TaqMan MicroRNA assays.

Results

A significant correlation was detected between serum and hepatic miR‐122 expression (correlation coefficient, 0.461; P = 0.005). Patients with mild steatosis (<33%) showed significantly lower levels of hepatic miR‐122 compared with patients with severe steatosis (>33%) (hepatic miR‐122: mild/severe = 2.158 ± 1.786/4.836 ± 7.506, P = 0.0473; serum miR‐122: mild/severe = 0.002 ± 0.005/0.007 ± 0.001, P = 0.0491). Moreover, hepatic and serum miR‐122 levels were significantly higher in patients with mild fibrosis than in those with severe fibrosis (hepatic miR‐122: mild/severe = 5.201 ± 7.275/2.394 ± 1.547, P = 0.0087; serum miR‐122: mild/severe = 0.008 ± 0.011/0.002 ± 0.004, P = 0.0191).

Conclusions

We found that the hepatic and serum miR‐122 levels were associated with hepatic steatosis and fibrosis. The serum miR‐122 level can be a useful predictive marker of liver fibrosis in patients with NAFLD.
Truth and the ‘Politics of Ourselves’
Authors: Anderson Russell , Wong James
Published: December 2013

The authors take up Amy Allen's suggestion that while Foucault's work may be able to support a certain type of self‐critique and self‐development, it does not permit the kind of interpersonal relations that are necessary for the development of intersubjective meaning in struggles against imposed identities. The authors contend that for Foucault, relations of ‘truth’ play an important constitutive role in subjectivities, and that understanding the ‘politics of ourselves’ in the context of this truth shows not only an openness to meaningful interpersonal relations, but also that these relations are capable of generating the conceptual and normative resources necessary for resisting socially imposed subjectivities. The authors present such an account of intersubjective relations based on Foucault's discussion of parrhesia, and develop a model of collaborative political action that addresses the criticisms raised.
The paraventricular nucleus and heart failure
Authors: Pyner Susan
Published: December 2013

New Findings

What is the topic of this review?

This review gives an update on the cellular and molecular mechanisms within the autonomic nervous system involved in non‐pathological and pathological cardiovascular regulation.

What advances does it highlight?

For cardiovascular homeostasis in non‐pathological conditions to be maintained, discrete neural networks using specified signalling mechanisms at both cellular and molecular levels are required. In heart failure, the cell signalling protein partners CAPON and PIN decrease the bioavailability of nitric oxide by inhibiting neuronal nitric oxide synthase activity, leading to the removal of tonic neuronal inhibition. Following a myocardial infarction, pro‐inflammatory cytokines in the paraventricular nucleus and the subsequent generation of reactive oxygen species, via angiotensin II activation of the angiotensin II type 1 receptor, increase neuronal excitability further, leading to sympathetic excitation.

A pathological feature of heart failure is abnormal control of the sympathetic nervous system. The paraventricular nucleus of the hypothalamus (PVN) is one of the most important central sites involved in regulating sympathetic tone and is, in part, responsible for the dysregulation of the sympathetic nervous system evident in heart failure. Generation of sympathetic tone in response to fluctuations in cardiovascular regulation uses discrete anatomical pathways and neurochemical modulators. Direct and indirect projections from the PVN pre‐autonomic neurons innervate the sympathetic preganglionic neurons in the spinal cord, which in turn innervate sympathetic ganglia that give rise to the sympathetic nerves. Pre‐autonomic neurons of the PVN themselves receive an afferent input arising from the nucleus tractus solitarii, and viscerosensory receptors convey cardiovascular fluctuations to the nucleus tractus solitarii. The PVN contains excitatory and inhibitory neurons, whose balance determines the sympathetic tone. In non‐pathological conditions, the tonic inhibition of the PVN pre‐autonomic neurons is mediated by GABA‐ and NO‐releasing neurons. In heart failure, the pre‐autonomic neurons are disinhibited by the actions of the excitatory neurotransmitters glutamate and angiotensin II, leading to increased sympathetic activity. A key feature of the disinhibition is a reduction in the bioavailability of NO as a consequence of disrupted CAPON and PIN signalling mechanisms within the neuron. Another critical feature that contributes to increased neuronal excitation within the PVN is the production of pro‐inflammatory cytokines immediately following a myocardial infarction, the activation of the angiotensin II type 1 receptor and the production of reactive oxygen species. By examining the changes associated with the sympathetic nervous system pathway, we will progress our understanding of sympathetic regulation in heart failure, identify gaps in our knowledge and suggest new therapeutic strategies.
Heterogeneous Void Nucleation Study in Flip Chip Assembly Process Using No-Flow Underfill
Authors: Lee Sangil , Baldwin Daniel F.
Published: December 2013

No-flow underfill process has exhibited a narrow feasible process window due to electrical assembly yield loss or underfill voiding. In general, the assembly yield can be improved using reflow process designed at high temperature, while the high temperature condition potentially causes serious underfill voiding. Typically, the underfill voiding can result in critical defects, such as solders fatigue cracking or solders bridge, causing early failures in thermal reliability. Therefore, this study reviews a classical bubble nucleation theory to model voids nucleation during reflow process. The established model designed a reflow process possibly preventing underfill voiding. The reflow process was validated using systematic experiments designed on the theoretical study with a commercial high I/O counts (5000>), fine-pitch (<150 μm) flip chip. The theoretical model exhibits good agreement with experimental results. Thus, this paper presents systematic studies through the use of structured experimentation designed to achieve a high, stable yield, and void-free assembly process on the classical bubble nucleation theory.
Crack Initiation and Propagation as Part of Engineering Design
Authors: Minnebo Hans , Duflot Marc , Wyart Eric
Published: December 2013

This article deals with the interest of the analysis of cracks in order to improve analysis design. Mainly oriented around the linear elastic fracture mechanics and fatigue crack propagation, it will also address some issues in non-linear fracture mechanics and crack insertion.
Theoretical and Experimental Vibration Analyses of Trapezoidal and Sinusoidal Corrugated Plates
Authors: Yucel Adil , Arpaci Alaeddin
Published: December 2013

In this study, dynamic behaviour of trapezoidal and sinusoidal corrugated plates which are widely used in the fields of space, aviation, automotive, construction and shipbuilding have been analyzed. 330 different surface models varying according to corrugation height and number have been created for these plates which have various manufacturing parameters. At this stage, the number of analyses is 660. These models have been analyzed for different boundary conditions and modal analyses to obtain natural frequencies and mode shapes have been conducted using finite element method. In addition, changes in the trapezoidal cross-section profile have also been investigated by analyzing 38 different plates with varying cross-section profiles. Examining these results, the effects of corrugation height and number on natural frequencies and mode shapes have been determined. As a result of the study a total of 368 drawings were prepared and 736 analyses were performed. Besides, the theoretical results have been verified using the experimental modal analysis technique for some selected models which are being manufactured in the market.
Modelling of an Unconventional Airship
Authors: Chaabani Said , Azouz Naoufel , Lerbet Jean , Abichou Azgal
Published: December 2013

This paper presents preliminary results of the modelling of an unconventional unmanned airship moving in an ideal fluid. We are studying here a quad-rotor flying wing.

The airships are also governed by the aerodynamic forces that have to be modelled. An evaluation of the added masses of the airship’s components is presented. A first dynamic modelling including the effect of the added masses is proposed.

A control law based on the elaborated dynamic model was applied to this large flying object to evaluate its sensitivity when manoeuvring over an uploading area.
Tracking Control for Switched Nonlinear Systems Subject to Time-Varying Output Constraints
Authors: Niu Ben , Dimirovski Georgi M. , Zhao Jun
Published: December 2013

In this paper, we address the tracking control problem for switched nonlinear systems in strict-feedback form with time-varying output constraints. To prevent the output from violating the time-varying constraints, we employ a Barrier Lyapunov Function, which relies explicitly on time. Based on the simultaneous domination assumption, we design a controller for the switched system, which guarantees that asymptotic tracking is achieved without transgression of the constraints and all closed-loop signals remain bounded under arbitrary switchings. The effectiveness of the proposed results is illustrated using a numerical example.
Proper Generalized Decomposition to Solve a 2D Coupled Heat-Diffusion Problem
Authors: Nguyen T. L. , Beringhier M. , Grandidier J. C.
Published: December 2013

To predict the effect of the environment on the durability of composites or polymers [3], we often have to consider coupled physical phenomena (thermo-diffuso-chemico-mechanic). Therefore, strongly coupled problems with a large number of characteristic times have to be considered. From a numerical point of view, solving these problems with the finite elements method requires the use of an incremental time scheme in which stability conditions lead to a large number of degrees of freedom and a large computation time.
Numerical Investigation on Nanofluid Mixed Convection in Triangular Ducts Heated by a Uniform Heat Flux
Authors: Manca O. , Nardini S. , Ricci D. , Tamburrino S.
Published: December 2013

Heat transfer enhancement technology covers a very important role in designing efficient heating and cooling equipments. This goal can be achieved by means of different techniques. Convective heat transfer can be improved actively or passively, for example, by adopting special surfaces or by increasing the thermal conductivity of the working fluids. Thus, the use of suspended solid nanoparticles in the working fluids can be taken into account. In this paper a numerical investigation on laminar mixed convection with Al2O3/water based nanofluids in a triangular channel is presented. A uniform and constant heat flux on the channel surfaces is assumed and the single-phase model approach has been employed in order to describe the nanofluid behaviour. The analysis has been performed in the steady state regime for particle size in nanofluids equal to 30 nm. The CFD code Fluent has been employed in order to solve the three-dimensional numerical model and different Richardson number values and nanoparticle volume fractions have been considered. Results are presented for the fully developed regime flow. The increase of average convective heat transfer coefficients and Nusselt number values for increasing values of Richardson number and particle concentration is observed by analyzing the obtained results. However, also wall shear stress and required pumping power profiles increase as expected.
Performance Analysis on the Internally Cooled Dehumidifier Using Two Liquid Desiccant Solutions
Authors: Koronaki I. P. , Christodoulaki R. I. , Papaefthimiou V. D. , Rogdakis E. D.
Published: December 2013

Liquid desiccant air conditioning systems have recently been attracting attention due to their capability of handling the latent load without super-cooling and then reheating the air, as happens in a conventional compression-type air conditioning system. This paper presents the results from a study of the performance of an internally cooled liquid desiccant dehumidifier. A plate heat exchanger is proposed as the internally cooled element of the dehumidifier and water as the cooling fluid. The desiccant solution is sprayed into the internally cooled dehumidifier from the top and flows down by gravity. At the same time, fresh humid air is blown from the bottom or top, counter-flowing or co-flowing with the desiccant solution. The desiccant is in direct contact with the air, allowing for heat and mass transfer. The cooling water, flowing inside the plates of the dehumidifier, carries out the heat of the crossed air and solution. A heat and mass transfer theoretical model has been developed, based on the Runge-Kutta fixed step method, to predict the performance of the device under various operating conditions. Experimental data from previous literature have been used to validate the model. Excellent agreement has been found between experimental tests and the theoretical model, with the deviation not exceeding ±4.1% for outlet air temperature and ±4.0% for outlet humidity ratio. Following the validation of the mathematical model, the dominating effects on the absorption process have been discussed in detail. Namely, effects of flow configuration, air inlet temperature, humidity and flow rate, as well as desiccant inlet temperature, concentration and flow rate have been investigated against the dehumidification rate and the cooling efficiency. The two most commonly used liquid desiccant solutions, namely LiCl and LiBr have been also evaluated against each other. The results suggested that high dehumidification mass rate can be achieved under counter flow between air and solution, low air mass flow rates, low cooling water temperature, low desiccant temperature and LiCl as the desiccant solution.
Multiscale Model Reduction for the Solution of Stochastic Partial Differential Equations With Localized Sources of Uncertainties
Authors: Safatly Elias , Chevreuil Mathilde , Nouy Anthony
Published: December 2013

The presence of numerous localized sources of uncertainties in stochastic models leads to high dimensional and multiscale problems. A numerical strategy is here proposed to propagate the uncertainties through such models. It is based on a multiscale domain decomposition method that exploits the localized side of uncertainties. The separation of scales has the double benefit of improving the conditioning of the problem as well as the convergence of tensor based methods (namely Proper Generalized Decomposition methods) used within the strategy for the separated representation of high dimensional stochastic parametric solutions.
PGD for Solving the Biharmonic Equation
Authors: Xu GuangTao , Chinesta Francisco , Leygue Adrien , Visonneau Michel
Published: December 2013

Biharmonic problem has been raised in many research fields, such as elasticity problem in plate geometries or the Stokes flow problem formulated by using the stream function. The fourth order partial differential equation can be solved by applying many techniques. When using finite elements C1 continuity must be assured. For this purpose Hermite interpolations constitute an appealing choice, but it imply the consideration of many degrees of freedom at each node with the consequent impact on the resulting discrete linear problem. Spectral approaches allow exponential convergence whilst a single degree of freedom is needed. However, the enforcement of boundary conditions remains a tricky task. In this paper we propose a separated representation of the stream function which transform the 2D solution in a sequence of 1D problems, each one be solved by using a spectral approximation.
Analysis and Design of a Robust RF MEMS Switch
Authors: Chamseddine Ibrahim , Kasab Hadi , Antoun Maya , Dahdah Tawfiq , Mirhi Mohammed , Lakkis Issam
Published: December 2013

A MEMS RF switch is expected to undergo 10 billion switching cycles before failure. Until complete physical explanation for these failure modes that include contact adhesion, damping effects, stiction, increases in resistance with time, dielectric breakdown, and electron trapping is fully established, the technology’s numerous advantages cannot be harvested reliably and efficiently. This paper investigates prospective solutions to problems in switch designs by proposing a new design for the switch. We consider the new design from different perspectives: dynamic, electric, fluidic, etc. It is billed to overcome the difficulties and involves the implementation of liquid metal contact electrostatically actuated to ensure the same switching performance, with prolonged life span, and robust switching speed.
Modelling IR-Heating in Stretch-Blow Moulding and Thermoforming
Authors: Rasche S. , Begemann M. , Hopmann Ch.
Published: December 2013

The two-stage stretch-blow moulding process has been established for the large scale production of high quality PET containers with excellent mechanical and optical properties. Thermoforming is the process of choice for manufacturing thin-gauge or large-area parts for packaging or technical applications. Both processes allow lightweight thermoplastic parts to be produced rapidly and economically.

In both processes thermoplastic semi-finished products are formed by pressurised air under the influence of heat. To enable forming of the thermoplastic materials, the semi-finished products need to be transferred into a thermoelastic state. IR-heating is widely used due to short heating times.

From a cost perspective, about 7 % of the total production costs of a stretch-blow moulded bottle are spent for energy in order to heat and form the preform to the later bottle. Depending on machine, semi-finished product type and cycle time, energy costs in thermoforming account for around 1–5 % of the total production costs. Modern roll-fed automatic thermoforming machines use about 22 % of the energy consumption for the heating step and around 70 % for the production of pressurised air. Due to this significant share and due to increasing energy costs during recent years, the packaging industry is interested in increasing the energy efficiency of these processes.

The most important quality criterion for both processes is a uniform wall thickness distribution. The production of high-quality parts requires optimised temperature profiles of the semi-finished product depending on the particular product geometry. Simulation is an approved tool for the prediction of the influence of the heater setting on the temperature profile.

Over the last decade IKV has developed an integrative three-dimensional process simulation which models the complete path of a preform through a stretch-blow moulding machine. An essential first step is the heating simulation where the temperature profile of the preform is computed. Based on this data the temperature-dependent material behaviour of PET can be considered during the inflation simulation.

This work shows the influence of a thoughtful temperature profile on the wall thickness distribution in stretch-blow moulding. The focus is on modelling the reheat phase of the stretch-blow moulding process in FEA. Beyond that, a purposeful heating offers the possibility to cut down energy waste.