bluuebunny/crossref_metadata_2025 huggingface dataset:
A socio-economic exploration of mobile phone service have-nots in Sweden
Authors: Annafari Mohammad T , Axelsson Ann-Sofie , Bohlin Erik
Published: May 2013

Most studies in the mobile communication field focus on the acceptance of the technology rather than the resistance of it, a trend that makes researchers try to understand only the powerful actors in society. Instead, this paper explores the socio-economic characteristics of mobile phone service have-nots. Based on an analysis of samples from three consecutive nationwide annual surveys in Sweden, this study finds that two socio-economic factors – age and the household income – remain significant to explain non-usage of mobile phone services. Other variables dynamically change over time without a significant effect. This finding supports the argument that most socio-economic factors are transient at different stages of the adoption of innovation. Since the benefits of mobile phones are related to social networks (the more people you know, the more beneficial), it is not surprising that, in the long run, elderly people with low income, who typically have a decreasing social network, find this technology no longer purposeful and finally refuse it. This indicates that the status of the have-nots may not reflect socio-economic inequalities in general, but rather individuals’ preference when managing their social situation. This is relevant with the argument that a universal service policy should be based on connectivity, that is, people’s need for communication rather than solely promoting subsidizing a particular technology or service. The policy, therefore, should consider the technological frame sharing – the interpretation of the technology shared by members of a relevant social group, that is, users, service providers and regulators, to bring a more socially constructed technology that can protect individuals with less socio-economic power from being socially excluded.
Urban brands, culture and social division: Creativity, tension and differentiation among middle class consumers
Authors: Bookman Sonia
Published: May 2013

This article considers the relationship between urban brands, consumption and socio-spatial division in the city, drawing on recent theoretical developments in the sociology of brands and empirical material from a study of the Exchange District in the city of Winnipeg, Canada. Focusing on the theme of creativity, the article uses interview data to examine how middle class residents, workers and visitors engage with the creative possibilities and cultural consumption the Exchange District brand offers. At stake in this process is not only the surfacing of a particular kind of creative culture and neighborhood, but also the performance and positioning of middle class identities. In this process, creativity is elaborated in contradictory and often unintended ways. Parallel to existing work on authenticity and class, the article argues that different notions and practices of creativity are bound up with tensions between moral and cultural boundaries, constituting horizontal divisions between the middle classes who inhabit this urban space.
Creativity and dementia: Does artistic activity affect well-being beyond the art class?
Authors: Gross Susan M. , Danilova Deana , Vandehey Michael A. , Diekhoff George M.
Published: May 2013

The Alzheimer’s Association’s Memories in the Making® (MIM) art activity program is intended to enhance the well-being of individuals who are living with dementia. Previous evaluations of MIM have found that participants show benefits on several well-being domains measured by the Greater Cincinnati Chapter Well-Being Observation Tool©. The current study extended those findings by looking for evidence of carry-over effects beyond the temporal boundaries of MIM sessions. Additionally, this study evaluated key psychometric qualities of the assessment instrument. Seventy-six MIM participants with middle- to late-stage dementia were evaluated by interns and care facility staff at the beginning, middle and end of a 12-week MIM program. Interns focused on behavior within MIM sessions and staff rated functioning outside MIM sessions. Staff reported no significant changes in resident well-being across the 12-week program. Interns reported significant improvements from the beginning to middle and end of the program on five well-being domains. Psychometric analyses of the Greater Cincinnati Chapter Well-Being Observation Tool© identified weaknesses in inter-rater reliability and found that the instrument measures two orthogonal factors – interpreted as ‘Well-Being’ and ‘Ill-Being’ – not the seven domains claimed. Quantitative evidence for the effectiveness of MIM is ambiguous, but anecdotal observations indicate that the program is beneficial for some participants, if only fleetingly.
Visualizations of coastal terrain time series
Authors: Tateosian Laura , Mitasova Helena , Thakur Sidharth , Hardin Eric , Russ Emily , Blundell Bruce
Published: May 2013

In coastal regions, water, wind, gravitation, vegetation, and human activity continuously alter landscape surfaces. Visualizations are important for understanding coastal landscape evolution and its driving processes. Visualizing change in highly dynamic coastal terrain poses a formidable challenge; the combination of natural and anthropogenic forces leads to cycles of retreat and recovery and complex morphology of landforms. In recent years, repeated high-resolution laser terrain scans have generated a time series of point cloud data that represent landscapes at snapshots in time, including the impacts of major storms. In this article, we build on existing approaches for visualizing spatial–temporal data to create a collection of perceptual visualizations to support coastal terrain evolution analysis. We extract terrain features and track their migration; we derive temporal summary maps and heat graphs that quantify the pattern of elevation change and sediment redistribution and use the space–time cube concept to create visualizations of terrain evolution. The space–time cube approach allows us to represent shoreline evolution as an isosurface extracted from a voxel model created by stacking time series of digital elevation models. We illustrate our approach on a series of Light Detection and Ranging surveys of sandy North Carolina barrier islands. Our results reveal terrain changes of shoreline and dune ridge migration, dune breaches and overwash, the formation of new dune ridges, and the construction and destruction of homes, changes which are due to erosion and accretion, hurricanes, and human activities. These events are all visualized within their geographic and temporal contexts.
A History of Comparative Advertising in the United States
Authors: Beard Fred K.
Published: May 2013

This historical monograph addresses a gap in the extensive scholarly research literature devoted to comparative advertising—especially that which contrasts the advertised product, service, or brand with an identifiable competitor—by exploring advertisers’ explanations for its appeal as a tactic throughout the previous century. Prior historical research confirms advertisers have long been aware of and greatly concerned about the unintended consequences of what they often called excessively competitive and combative advertising. Moreover, despite some thirty-five years of systematic scholarly research, two research teams recently concluded that the state of empirical knowledge regarding its effectiveness remains “equivocal.” By synthesizing the extensive theoretical and empirical research literature on comparative advertising and interpreting those findings from a historical perspective, this monograph offers uniquely significant insights into modern advertising’s history, theory, and practice.
Lines of Affect and Performativity
Authors: Swirski Teresa
Published: May 2013

Qualitative research data comes in a myriad of forms and permutations. This spectrum of inquiry spans differing assemblages of sensation, creation, and well-being. While affording methodological moments their place, it is suggested that understanding sensation as “affect” and creation as “performativity” can provoke new qualitative research lines to unfold, alongside the politics of well-being. The intent of this article is to explore how continuing to transverse material, social, and temporal practices can spark new disruptions and notions of data. It is argued that further innovating data involves becoming more attuned to the lines and layers of our material, social, and temporal practices. Opening ourselves up to the interplay of sensation, creation, and well-being provides a rich optic for future qualitative methodologies—enabling us to reconfigure the territories of response and responsibility.
Case report and review of the literatureTotal Endovascular Repair of Acute Ascending Aortic Rupture
Authors: McCallum John C. , Limmer Karl K. , Perricone Anthony , Bandyk Dennis , Kansal Nikhil
Published: May 2013

Thoracic aortic endografting has been successfully implemented to treat aneurysmal disease of the distal aortic arch and descending thoracic aorta. Although there are reports of ascending aortic endovascular interventions, the total endovascular repair of a ruptured ascending aorta secondary to a Type A dissection has not been described. We report the case of a 77-year-old patient who presented with a ruptured ascending aortic aneurysm secondary to degeneration of a Stanford type A aortic dissection. His surgical history was significant for orthotropic heart transplant 19 years prior. The dissection, aneurysm, and rupture occurred in the native aorta distal to the ascending aortic suture line. At presentation, he was hemodynamically unstable with a right hemothorax. We placed 3 Medtronic Talent Thoracic Stent Graft devices (Medtronic Inc, Minneapolis, MN) across the suture line in the ascending aorta, excluding the rupture. The patient survived and has been followed to 25 months.
Individualism and collectivism in Chinese and American television advertising
Authors: Hsu Siu Yu , Barker Gina G
Published: May 2013

This study examined the cultural values promoted in television advertisements targeting younger and older audiences in China and the US, respectively, testing the hypothesis that ads in China would reflect a value shift caused by the open-door policy implemented in 1979. A content analysis of 566 television ads was conducted, rating the degree of individualism and collectivism, as well as the prominence of modern and traditional themes. As predicted, ads targeting younger Chinese scored higher in individualism than collectivism. Compared to ads targeting the older demographic, ads targeting younger Chinese scored higher in individualism, with no significant differences in the other three dimensions. As expected, mean scores for individualism and modernity were higher in the American ads, while mean scores for collectivism and tradition were lower. The results revealed no differences in the scores between younger and older audiences in the US.
Long-term clinical results and MRI changes after tendon ball arthroplasty for advanced Kienböck’s disease
Authors: Mariconda M. , Soscia E. , Sirignano C. , Smeraglia F. , Soldati A. , Balato G.
Published: May 2013

The purpose of this study was to assess the long-term clinical results and morphological changes after tendon ball arthroplasty for advanced Kienböck’s disease. Twenty-six patients were reviewed, with a mean follow-up interval of 125 months (range 50–226). At follow-up, mean score on the Disabilities of the Arm, Shoulder, and Hand questionnaire was 7.7 and mean visual analogue scale score for pain was 1. Mean carpal height ratio was significantly reduced with respect to the pre-operative value. On magnetic resonance imaging scans, cartilage damage, synovitis, and erosive or oedematous changes in the bones were detected in most patients. Calcification in the defect filled by the tendon ball was seen in all patients. Narrowing of the radioscaphoid joint and the presence of intercarpal synovitis were negatively associated with clinical outcome. Tendon ball arthroplasty in advanced Kienböck’s disease results in long-term satisfactory clinical outcomes, despite widespread changes in the bones and joints within the wrist.
Cochrane corner: ergonomic positioning or equipment for treating carpal tunnel syndrome
Authors: Buchan S. , Amirfeyz R.
Published: May 2013

Background:

Non-surgical treatments, including ergonomic positioning or equipment, are sometimes offered to people experiencing mild to moderate symptoms from carpal tunnel syndrome. The effectiveness and duration from ergonomic positioning or equipment interventions for treating carpal tunnel syndrome are unknown.

Objectives:

To assess the effects of ergonomic positioning compared with no treatment, a placebo or another non-surgical intervention in people with carpal tunnel syndrome.

Search methods:

We searched the Cochrane Neuromuscular Disease Group Specialized Register (14 June 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (2011, Issue 2, in The Cochrane Library), MEDLINE (1966 to June 2011), EMBASE (1980 to June 2011), CINAHL Plus (1937 to June 2011), and AMED (1985 to June 2011). We also reviewed the reference lists of randomized or quasi-randomized trials identified from the electronic search.

Selection criteria:

Randomized or quasi-randomized controlled trials comparing ergonomic positioning or equipment with no treatment, placebo or another non-surgical intervention in people with carpal tunnel syndrome.

Data collection and analysis:

Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias of included studies. They calculated risk ratios and mean differences with 95% confidence intervals for the primary and secondary outcomes. Results of clinically and statistically homogeneous trials were pooled, where possible, to provide estimates of the effect of ergonomic positioning or equipment.
The diagnostic accuracy of wrist cineradiography in diagnosing scapholunate dissociation
Authors: Sulkers G. S. I. , Schep N. W. L. , Maas M. , van der Horst C. M. A. M. , Goslings J. C. , Strackee S. D.
Published: May 2013

Ruptures of the scapholunate ligament (SLL) may cause carpal instability, also known as scapholunate dissociation (SLD). SLD may lead to osteoarthritis of the radiocarpal and midcarpal joints. The aim of this retrospective study was to determine the diagnostic value of wrist cineradiography in detecting SLD. All cineradiographic studies made during a 24 year period were retrieved. All patients who underwent the confirmation method (arthroscopy and/or arthrotomy) and cineradiography were included. In total, 84 patients met the inclusion criteria. Sensitivity, specificity, likelihood ratio, positive predictive value, negative predictive value, and diagnostic accuracy for detecting SLD were calculated for radiography and cineradiography. Cineradiography had a sensitivity of 90%, a specificity of 97%, and a diagnostic accuracy of 0.93 in detecting SLD. Radiography had a sensitivity of 81%, a specificity of 80%, and a diagnostic accuracy of 0.81. Cineradiography has a high diagnostic value for diagnosing SLDs. A positive cineradiography markedly increases the post-test probability of SLD.
Torsion stiffness of a racing cross-country ski boot
Authors: Hladnik Jurij , Resman Franc , Jerman Boris
Published: May 2013

This article presents a study of torsion stiffness of a specific racing cross-country ski boot for the skating technique conducted by means of numerical analyses and measurements. Its aim is to determine relative torsion stiffness contributions, relative mass contributions, and the ratios between them (torsion stiffness/mass ratios) for individual boot components of the torsionally most deformable part of the boot. These are basic data for torsion stiffness–mass optimization of the boot. For acquiring these data, a complex finite element model of the cross-country ski boot and an artificial silicone foot were created in different versions after an existing device designed for measurement of stiffness properties of the boots. Material properties employed in the model were acquired experimentally. The confirmed model was used for determination of the torsion deformation contributions of different regions of the boot. Focus was given to the middle region, whose contribution is the largest. The aforementioned data were determined for individual boot components of this region. The soles, which contribute the most to the middle region’s torsion stiffness, turned out to have the highest potential for torsion stiffness–mass optimization, because of their lowest torsion stiffness/mass ratio and highest mass contribution. The shoe-upper has the highest torsion stiffness/mass ratio and is, therefore, the most worthwhile to be enlarged. The torsion stiffness/mass ratio of the strengthening bands is lower than expected and could likely be increased by their positioning.
Catheter-based renal denervation for treatment of resistant hypertension
Authors: Hatipoglu Emine , Ferro Albert
Published: May 2013

Hypertension is a common disease associated with important cardiovascular complications. Persistent blood pressure of 140/90 or higher despite combined use of a reninangiotensin system blocker, calcium channel blocker and a diuretic at highest tolerated doses constitutes resistant hypertension. Excess sympathetic activity plays an important pathogenic role in resistant hypertension in addition to contributing to the development of metabolic problems, in particular diabetes. Reduction of renal sympathetic activity by percutaneous catheter-based radiofrequency ablation via the renal arteries has been shown in several studies to decrease blood pressure in patients with resistant hypertension, and importantly is largely free of significant complications. However, longer term follow-up is required to confirm both long-term safety and efficacy.
Diabetes is associated with posttranslational modifications in plasminogen resulting in reduced plasmin generation and enzyme-specific activity
Authors: Ajjan Ramzi A. , Gamlen Toby , Standeven Kristina F. , Mughal Salihah , Hess Katharina , Smith Kerrie A. , Dunn Emma J. , Anwar M. Maqsud , Rabbani Naila , Thornalley Paul J. , Philippou Helen , Grant Peter J.
Published: May 2013

Key Points

Plasminogen is glycated in diabetes, resulting in reduced plasmin generation and impaired protein activity. Impaired plasminogen function and the consequent hypofibrinolysis in diabetes are reversible by modest improvement in glycemia.
Middle-preserving pancreatectomy: report of two cases and review of the literature
Authors: Cheng Kun , Shen Bai-yong , Peng Cheng-hong , Na Li-ma , Cheng Dong-feng
Published: May 2013

Background

Middle-preserving pancreatectomy (MPP) is a parenchyma-sparing surgical procedure which has recently been sporadically reported for the treatment of multicentric periampullary-pancreatic lesions. However, a comprehensive recognition of this procedure has not been clearly elucidated.

Case presentation

We herein report two patients undergoing MPP due to synchronous multicentric pancreatic neoplasm. Patient one was a 24-year-old woman with a multicentric solid pseudopapillary neoplasm (SPN) and patient two was a 36-year-old woman with a multicentric serous cystic neoplasm (SCN). Simultaneous atypical pancreaticoduodenectomy and atypical left pancreatectomy were performed in patient one; simultaneous standard pancreaticoduodenectomy and atypical left pancreatectomy with spleen preservation were performed in patient two. Approximately 6 cm and 5 cm segments of the middle portion of the pancreas were preserved, respectively. At follow-up at 36 months and 6 months respectively, patient one had developed diabetes and malabsorption requiring dietary control, exercise and pancreatic enzyme supplement whereas patient two showed normal fasting blood glucose without diarrhea. Both patients were disease-free and in good nutritional condition. We reviewed twenty cases of MPP that were previously reported in the literature. Patient characteristics, surgical techniques and short- and long-term outcomes were analyzed.

Conclusion

MPP is mainly beneficial for multicentric noninvasive periampullary-pancreatic lesions. However, for multicentric periampullary-pancreatic lesions involving even primary invasive cancers, as long as the invasive cancers affect only one side of the pancreas (proximal or distal), MPP could serve as a rational choice in well-selected patients.
Effects of ethanol on immune response in the brain: region-specific changes in aged mice
Authors: Kane Cynthia JM , Phelan Kevin D , Douglas James C , Wagoner Gail , Johnson Jennifer Walker , Xu Jihong , Drew Paul D
Published: May 2013

Background

Alcohol abuse has dramatic effects on the health of the elderly. Recent studies indicate that ethanol increases immune activity in younger animals and that some of these proinflammatory molecules alter alcohol consumption and addiction. However, the effects of alcohol on immune activation in aged animals have not been thoroughly investigated.

Findings

We compared the effects of ethanol on chemokine and cytokine expression in the hippocampus, cerebellum, and cerebral cortex of aged C57BL/6 mice. Mice were treated via gavage with 6 g/kg ethanol for 10 days and tissue was harvested 1 day post-treatment. Ethanol selectively increased mRNA levels of the chemokine (C-C motif) ligand 2/monocyte chemotactic protein-1 in the hippocampus and cerebellum, but not in the cortex of aged mice relative to control animals. In this paradigm, ethanol did not affect mRNA levels of the cytokines IL-6 or TNF-α in any of these brain regions in aged animals.

Conclusions

Collectively, these data indicate a region-specific susceptibility to ethanol regulation of neuroinflammatory and addiction-related molecules in aged mice. These studies could have important implications concerning alcohol-induced neuropathology and alcohol addiction in the elderly.
Immunocytochemical studies reveal novel neural structures in nemertean pilidium larvae and provide evidence for incorporation of larval components into the juvenile nervous system
Authors: Hindinger Sabine , Schwaha Thomas , Wanninger Andreas
Published: May 2013

Introduction

Nemertea is one of the least studied lophotrochozoan phyla concerning neurogenesis. The sparse data available do not unambiguously allow for answering questions with respect to the neural groundplan of the phylum or the fate of larval neural structures during metamorphosis. In order to contribute to this issue, we studied neurotransmitter distribution during development of the pilidiophoran Lineus albocinctus Verrill, 1900.

Results

Two serotonin-like immunoreactive (lir) neurons are present in the anterior part of the apical plate. They send numerous processes into the four lobes of the pilidium larva, where they form a complex subepithelial nerve net. All four larval lobes are underlain by a marginal neurite bundle, which is associated with numerous serotonin-lir monociliated perikarya. A serotonin-lir oral nerve ring encircles the stomach sphincter and is associated with few serotonin-lir conical cells. Two suboral neurites descend from the oral nerve ring and merge with the marginal neurite bundle. The oral nerve ring and the suboral neurites contain the mollusk-specific VD1/RPD2 α-neuropeptide. The lateral lobes of the larva have three and the anterior and the posterior lobes two VD1/RPD2-lir marginal neurite bundles. The lobar FMRFamide-lir plexus of Lineus albocinctus is much more complex than previously described for any pilidium larva. It includes a circumesophageal neurite that descends along each side of the larval esophagus and together with the inner marginal neurite bundle gives rise to the lobar plexus of the lateral lobes. An outer FMRFamide-lir marginal neurite bundle with numerous associated FMRFamide-lir marginal sensory cells surrounds all four lobes. FMRFamide-lir structures are absent in the larval apical region. The oral nerve ring and the two suboral serotonin-lir neurites are incorporated into the juvenile nervous system.

Conclusion

Our study confirms the presence of serotonin-lir components in the apical region of the pilidium larva of Lineus albocinctus and thus contradicts an earlier study on the same species. We show that the nervous system of pilidium larvae, especially the FMRFamide-lir components, is much more complex than previously assumed. The presence of the VD1/RPD2-α-neuropeptide indicates that this compound may have been part of the lophotrochozoan neural groundplan.
Health care management of sickness certification tasks: results from two surveys to physicians
Authors: Lindholm Christina , von Knorring Mia , Arrelöv Britt , Nilsson Gunnar , Hinas Elin , Alexanderson Kristina
Published: May 2013

Background

Health care in general and physicians in particular, play an important role in patients’ sickness certification processes. However, a lack of management within health care regarding how sickness certification is carried out has been identified in Sweden. A variety of interventions to increase the quality of sickness certification were introduced by the government and County Councils. Some of these measures were specifically aimed at strengthening health care management of sickness certification; e.g. policy making and management support. The aim was to describe to what extent physicians in different medical specialties had access to a joint policy regarding sickness certification in their clinical settings and experienced management support in carrying out sickness certification.

Method

A descriptive study, based on data from two cross-sectional questionnaires sent to all physicians in the Stockholm County regarding their sickness certification practice. Criteria for inclusion in this study were working in a clinical setting, being a board-certified specialist, <65 years of age, and having sickness certification consultations at least a few times a year. These criteria were met by 2497 physicians in 2004 and 2204 physicians in 2008. Proportions were calculated regarding access to policy and management support, stratified according to medical specialty.

Results

The proportions of physicians working in clinical settings with a well-established policy regarding sickness certification were generally low both in 2004 and 2008, but varied greatly between different types of medical specialties (from 6.1% to 46.9%). Also, reports of access to substantial management support regarding sickness certification varied greatly between medical specialties (from 10.5% to 48.8%). More than one third of the physicians reported having no such management support.

Conclusions

Most physicians did not work in a clinical setting with a well-established policy on sickness certification tasks, nor did they experience substantial support from their manager. The results indicate a need of strengthening health care management of sickness certification tasks in order to better support physicians in these tasks.
Microwave assisted solubilization of inclusion bodies
Authors: Datta Ishara , Gautam Saurabh , Gupta Munishwar N
Published: May 2013

Background

Production of recombinant proteins in bacterial hosts often produces insoluble intracellular particles called inclusion bodies. Recovery of active protein from inclusion bodies generally requires their solubilization in chemical denaturants followed by a refolding strategy. The solubilization is carried out with shaking/stirring and takes several hours.

Results

Using inclusion bodies of seven diverse kinds of recombinant proteins [mutants of controller of cell division or death protein B (CcdB), human CD4D12, thioredoxin fusion protein (malETrx), mutants of maltose binding protein (MBP), single chain variable fragment (ScFv) b12 and single chain antigen binding fragment (ScFab) b12 (anti-HIV-1)], it is shown that exposure to microwave irradiation (200 W) for 2 min, solubilized these inclusion bodies completely. This was confirmed by data based upon turbidity measurements at 400 nm and dynamic light scattering studies. These solubilized inclusion bodies could be refolded correctly in all the cases by known methods. The refolding was confirmed by fluorescence emission spectra and biological activity studies.

Conclusion

Solubilization of the inclusion bodies before refolding is a part of protein production processes for several recombinant proteins which are overexpressed in the bacterial host systems. Our results show that microwave assistance can considerably shorten the process time.
Glycated Albumin Causes Pancreatic β-Cells Dysfunction Through Autophagy Dysfunction
Authors: Song Young Mi , Song Sun Ok , You Young-Hye , Yoon Kun-Ho , Kang Eun Seok , Cha Bong Soo , Lee Hyun Chul , Kim Ji-Won , Lee Byung-Wan
Published: May 2013

Growing evidence suggests that advanced glycation end-products (AGEs) are cytotoxic to pancreatic β-cells. The aims of this study were to investigate whether glycated albumin (GA), an early precursor of AGEs, would induce dysfunction in pancreatic β-cells and to determine which kinds of cellular mechanisms are activated in GA-induced β-cell apoptosis. Decreased viability and increased apoptosis were induced in INS-1 cells treated with 2.5 mg/mL GA under 16.7mM high-glucose conditions. Insulin content and glucose-stimulated secretion from isolated rat islets were reduced in 2.5 mg/mL GA-treated cells. In response to 2.5 mg/mL GA in INS-1 cells, autophagy induction and flux decreased as assessed by green fluorescent protein–microtubule-associated protein 1 light chain 3 dots, microtubule-associated protein 1 light chain 3-II conversion, and SQSTM1/p62 in the presence and absence of bafilomycin A1. Accumulated SQSTM1/p62 through deficient autophagy activated the nuclear factor-κB (p65)-inducible nitric oxide synthase-caspase-3 cascade, which was restored by treatment with small interfering RNA against p62. Small interfering RNA treatment against autophagy-related protein 5 significantly inhibited the autophagy machinery resulting in a significant increase in iNOS-cleaved caspase-3 expression. Treatment with 500μM 4-phenyl butyric acid significantly alleviated the expression of endoplasmic reticulum stress markers and iNOS in parallel with upregulated autophagy induction. However, in the presence of bafilomycin A1, the decreased viability of INS-1 cells was not recovered. Glycated albumin, an early precursor of AGE, caused pancreatic β-cell death by inhibiting autophagy induction and flux, resulting in nuclear factor-κB (p65)-iNOS-caspase-3 cascade activation as well as by increasing susceptibility to endoplasmic reticulum stress and oxidative stress.
Integrated Effects of Leptin in the Forebrain and Hindbrain of Male Rats
Authors: Desai Bhavna N. , Harris Ruth B. S.
Published: May 2013

Leptin receptors (ObRs) in the forebrain and hindbrain have been independently recognized as important mediators of leptin responses. It is unclear how leptin activity in these areas is integrated. We tested whether both forebrain and hindbrain ObRs have to be activated simultaneously to change energy balance and to maintain metabolic homeostasis. Previous studies used acute leptin injections in either the third ventricle (1–5 μg) or the fourth ventricle (3–10 μg); here we used 12-day infusions of low doses of leptin in one or both ventricles (0.1 μg/24 h in third, 0.6 μg/24 h in fourth). Male Sprague Dawley rats were fitted with third and fourth ventricle cannulas, and saline or leptin was infused from Alzet pumps for 6 or 12 days. Rats that received leptin into only the third or the fourth ventricle were not different from controls that received saline in both ventricles. By contrast, rats with low-dose leptin infusions into both the third and fourth ventricle showed a dramatic 60% reduction in food intake that was reversed on day 6, a 20% weight loss that stabilized on day 6, and a 50% decrease in body fat at day 12 despite the correction of food intake. They displayed normal activity and maintained energy expenditure despite weight loss, indicating inappropriately high thermogenesis that coincided with increased signal transducer and activator of transcription 3 (STAT3) phosphorylation in the brainstem. Altogether, these findings show that with low doses of leptin, chronic activation of both hypothalamic and brainstem ObRs is required to reduce body fat.
Why Market Failures Are Not a Problem: James Buchanan on Market Imperfections, Voluntary Cooperation, and Externalities
Authors: Marciano Alain
Published: May 2013

This article describes the intellectual trajectory James Buchanan followed from the early 1950s, when he started to work on ``spillover effects,'' to the mid-1960s, when he had completed a consistent explanation of the efficiency of market mechanisms and private arrangements in the presence of externalities. We show that, in contrast with what most economists admit, Buchanan argued that, even if externalities are a cause of ``market failures,'' this cannot be used to legitimate the intervention of the state, because individuals tend to pay for the external effects their actions generate. By adopting a historical perspective, we are able to show the remarkable consistency of Buchanan's claims about externalities, even though he developed them in a period when the views of economists on the question were changing dramatically.
Utilitarianism and Luck
Authors: Persky Joseph
Published: May 2013

The study of luck in moral and political philosophy has generated two camps: the ``luck egalitarians,'' who see justice as demanding aggressive efforts to reduce inequalities produced by luck broadly conceived, and the advocates of ``democratic equality,'' who emphasize traditional liberal political values. Most of this literature has been ahistorical and hostile to utilitarianism. This essay aims at repositioning the luck debates in the context of John Stuart Mill's oft maligned essay, Utilitarianism. There, Mill posits that the historical progress of justice works against all types of social expediency, thus reducing the role of luck in human affairs. Over time, justice requires a move from ``democratic equality'' to the achievement of ``luck egalitarianism.'' Rather than viewing these as competing approaches to justice, this reading of Mill views them as succeeding stages in the conquest of poverty and the historical achievement of justice. These themes in Utilitarianism also go far toward reconciling that essay with Mill's utilitarian roots.
ArhGEF18 regulates RhoA-Rock2 signaling to maintain neuro-epithelial apico-basal polarity and proliferation
Authors: Herder Cathrin , Swiercz Jakub M. , Müller Claudia , Peravali Ravindra , Quiring Rebecca , Offermanns Stefan , Wittbrodt Joachim , Loosli Felix
Published: May 2013

The vertebrate central nervous system develops from an epithelium where cells are polarized along the apicobasal axis. Loss of this polarity results in abnormal organ architecture, morphology and proliferation. We found that mutations of the guanine nucleotide exchange factor ArhGEF18 affect apicobasal polarity of the retinal neuroepithelium in medaka fish. We show that ArhGEF18-mediated activation of the small GTPase RhoA is required to maintain apicobasal polarity at the onset of retinal differentiation and to control the ratio of neurogenic to proliferative cell divisions. RhoA signals through Rock2 to regulate apicobasal polarity, tight junction localization and the cortical actin cytoskeleton. The human ArhGEF18 homologue can rescue the mutant phenotype, suggesting a conserved function in vertebrate neuroepithelia. Our analysis identifies ArhGEF18 as a key regulator of tissue architecture and function, controlling apicobasal polarity and proliferation through RhoA activation. We thus identify the control of neuroepithelial apicobasal polarity as a novel role for RhoA signaling in vertebrate development.
The Localization of Ultraviolet-Induced Excision Repair in the Nucleus and the Distribution of Repair Events in Higher Order Chromatin Loops in Mammalian Cells
Authors: Mullenders L. H. F. , Zeeland A. A. Van , Natarajan A. T.
Published: May 2013

Several lines of evidence indicate that eukaryotic DNA is arranged in highly supercoiled domains or loops, and that the repeating loops are constrained by attachment to a nuclear skeletal structure termed the nuclear matrix. Active genes are transcribed at the nuclear matrix and during replication the loops are reeled through fixed matrix-associated replication complexes. We have investigated whether the repair of DNA damage also occurs in the nuclear matrix compartment. Biochemical analysis of confluent normal human fibroblasts, ultraviolet (u.v.)-irradiated with 30 J m−2 and post-u. v. incubated in the presence of hydroxyurea, did not show any evidence for the occurrence of repair synthesis at the nuclear matrix either 30 min or 13 h after irradiation. Autoradiographic visualization of repair events in single DNA halo-matrix structures confirmed the biochemical observations. At a biologically more relevant dose of 5 J m−2 repair synthesis seems to initiate at the nuclear matrix, although only part of the total repair could be localized there. In u.v.-irradiated (30 J m−2) normal human fibroblasts post-u.v. incubated in the presence of hydroxyurea and arabinosylcytosine for 2h, multiple single-stranded regions are generated in a DNA loop as a result of the inhibition of the excision repair process. Different biochemical approaches revealed that most of the single-stranded regions are clustered, indicating that the repair process itself is non-random or that domains in the chromatin are repaired at different rates. Preferential repair of certain domains in the chromatin was shown to occur in xeroderma pigmentosum cells of complementation group C (XP-C). In XP-C cells these domains are localized near the attachment sites of DNA loops at the nuclear matrix. In contrast, xeroderma pigmentosum cells of complementation group D as well as Syrian hamster embryonic cells with limited excision-repair capacities, revealed a random distribution of repair events in DNA loops. The preferential repair of matrix-associated DNA in XP-C cells may be related partly to repair of transcriptionally active DNA and this may account for the ability of XP-C cells, in contrast to XP- D cells, to recover u.v.-inhibited synthesis of DNA and RNA.
Excision Repair in the Yeast, Saccharomyces Cerevisiae
Authors: Mccready Shirley J. , Boyce Joy M. , Cox Brian S.
Published: May 2013

cdc9 mutants of yeast lack detectable DNA ligase activity at restrictive temperatures. They also appear to be more sensitive than wild-type cells to ultraviolet (u.v.) radiation and it has been assumed that this is because the CDC9 ligase is needed for the final ligation step in excision repair. The fact that single-strand breaks have been demonstrated in u.v.-irradiated cdc9 mutants has been regarded as evidence for this interpretation. However, the kinetics of appearance of nicks in the DNA do not support this since maximal levels of strand breaks appear almost immediately after exposure to u.v. light and not progressively as repair events are initiated. We believe, therefore, that these strand breaks are connected with a u.v.-dependent preincision event, possibly connected with reorganization of chromatin.
Initiating DNA synthesis: from recruiting to activating the MCM complex
Authors: Lei Ming , Tye Bik K.
Published: May 2013

The exact duplication of a genome once per cell division is required of every proliferating cell. To achieve this goal, eukaryotes adopt a strategy that limits every replication origin to a single initiation event within a narrow window of the cell cycle by temporally separating the assembly of the pre-replication complex (pre-RC) from the initiation of DNA synthesis. A key component of the pre-RC is the hexameric MCM complex, which is also the presumed helicase of the growing forks. An elaborate mechanism recruits the MCM complex to replication origins, and a regulatory chain reaction converts the poised, but inactive, MCM complex into an enzymatically active helicase. A growing list of proteins, including Mcm10 and Cdt1, are involved in the recruitment process. Two protein kinases, the Cdc7-Dbf4 kinase (DDK) and the cyclin-dependent kinase (CDK), trigger a chain reaction that results in the phosphorylation of the MCM complex and finally in the initiation of DNA synthesis. A composite picture from recent studies suggests that DDK is recruited to the pre-RC during G1 phase but must wait until S phase to phosphorylate the MCM complex. CDK is required for the recruitment of Cdc45 and other downstream components of the elongation machinery.
In vitro glucan synthesis by membranes of celery petioles: the role of the membrane in determining the type of linkage formed
Authors: Jacob Sally R. , Northcote D. H.
Published: May 2013

Glucan synthesis was achieved with an in vitro membrane fraction from the petioles of celery (Apiumgraveolens). The optimum conditions for maximum synthesis were established. The Km and Vmax for the enzymic system were 1·0mM and 0·19gMmin-1mg protein-1, respectively.

Mechanical damage to the membrane fraction altered the proportion of β-(l→3) to β-(l→4) glucosyl linkages that were synthesized. We suggest that cellulose synthesis β-(l→4)-linked glucan chains) is controlled by the availability of UDP-glucose at the plasma membrane surface in conjunction with an organized relationship between the synthase system and a specifically oriented glucosyl radical acting as an acceptor held on the membrane surface. An intact membrane is therefore necessary to direct synthesis for the β-(1 →4) bond by an enzyme that is capable of transglucosyla- tion to the secondary alcoholic groups on C-2, C-3 or C-4 of the acceptor radical. The specificity of the system is controlled by the whole enzyme complex held on the membrane.
Surface of the shoot apex: a reinforcement-field theory for phyllotaxis
Authors: Green Paul B.
Published: May 2013

Theory for leaf patterning, phyllotaxis, is usually expressed in terms of interactions in the surface of the apical dome of the shoot. Mechanisms for leaf formation, however, usually relate to phenomena in the longitudinal section, e.g. periclinal divisions. Studying epidermal cell file patterns and the directionality of cellulose in the outer walls of the dome we have found distinct patterns of cells and reinforcing cellulose on the surface. Changes in the epidermal pattern correlate with the phyllotactic sequence to suggest that :

Recently established leaves are associated with fields of tangential cellulose reinforcement which extend toward the apical dome. Where such aligned fields come into contact so as to generate relatively abrupt angular changes in reinforcement pattern, a new leaf will appear. As this region of discontinuity develops into a hoop-reinforced structure, the visible primor-dium, a new single field of tangentially aligned reinforcement is generated. The new field interacts with other fields to continue the cycle.

In whorled phyllotaxis two angular discontinuities appear to be involved with each new leaf; the pertinent older leaves are just one plastochron older than the leaf being initiated. In spiral phyllotaxis (3:2) a single angular discontinuity appears to be involved initially; the pertinent older leaves are three and five plastochrons older than the leaf being formed.

There are two major differences from previous theories of phyllotaxis. First, the cyclic changes in leaf initiation are thought to be based on the constructive involvement of new leaves in modifying the dome’s reinforcement pattern. Many theories assume that leaf formation is spontaneous and the role of nearby leaves is inhibitory. Second, the pattern sequence can explain the concurrent appearance of reinforced stem tissue along with leaves.
Characterization of chlamydomonas sexual agglutinins
Authors: Adair W. S.
Published: May 2013

Molecules (agglutinins) mediating mating-type-specific adhesion of Chlamydomonas reinhardtii plus and minus gametes have been purified and shown to be homologous by several criteria. Both are large, extrinsic glycoproteins, rich in hydroxyproline and serine, which display similar sensitivities to a variety of inactivating agents. Direct visualization of agglutinins by the rapid-freeze deep-etch technique of Heuser reveals that both are extremely asymmetric, fibrous molecules with similar but distinct topographies. Each has a globular head, a rigid domain, a relatively flexible region and a terminal hook. In situ images show that the molecules associate with the flagellar surface via the latter (hook) domain, projecting the globular head distally. A functional role for the head is implied from inactivation studies (thermolysin digestion and reduction/alkylation) showing a selective modification of this domain.

A library of monoclonal antibodies, raised against thep/zw agglutinin, has been used to probe the structural organization of this molecule by immunotopographic mapping. Two distinct classes of monoclonal antibodies are shown to react with carbohydrate epitopes localized to the two termini (head and hook) of the plus agglutinin while a third recognizes a polypeptide determinant that repeats along the rod-like portion of the molecule. The latter class is gamete (but not mating-type)-specific while the other two classes display distinct patterns of cross reactivity.

Finally, the Chlamydomonas agglutinins show a striking compositional and structural resemblance to the major cell wall glycoproteins of this organism. Wall glycoproteins, which are also rich in hydroxyproline and serine and capable of self-assembly, may therefore share a common evolutionary heritage with the agglutinins.
Preprophase bands, phragmoplasts, and spatial control of cytokinesis
Authors: Gunning B. E. S. , Wick S. M.
Published: May 2013

Features of preprophase bands (PPBs) of microtubules (MTs), and the spatial relationship between phragmosomes, PPB sites, and developing phragmoplasts during cytokinesis, are reviewed, setting new observations in the context of current knowledge.

PPBs in onion root tip cells are present by the beginning of the G2 period of the cell cycle. They are at first wide, but later become more compact, narrower bands. MTs traverse the cytoplasm between the band at the cell cortex and the nuclear envelope. This whole assemblage of nucleus, PPB and intervening MTs remains together when the cell is ruptured during preparation for examination by immunofluorescence microscopy. Double bands are occasionally seen in early stages of PPB development, perhaps as a consequence of double induction from neighbouring cells. Calmodulin is not present in PPBs at a higher concentration than in the general cytoplasm, but it is more abundant in parts of the spindle and in the phragmoplast.

The PPB MTs disappear at prophase, but nevertheless the new cell plate fuses with the parental cell walls at the PPB site. This spatial relationship can be disrupted by treatment with CIPC. Another experimental disruption of the relationship, accomplished by making minute wounds in the PPB site of mitotic cells in Tradescantia stamen hairs, is described. In other experiments on these cells the phragmoplast is shown to become tethered to the PPB site when the cell plate is half to three-quarters developed, although the telophase nuclei are free to move. Rhodamine-labelled phalloidin reveals putative F-actin in the phragmoplast of Tradescantia, but not in the gap between the extending phragmoplast and the PPB site. Rhodamine-labelled phalloidin also stains cytoplasmic strands that exist when cytoplasmic streaming occurs before and after (but not during) mitosis. Cytochalasin B treatment blocks incorporation of actin into the phragmoplast, which, however, can still develop, though usually abnormally. The F-actin of the phragmoplast may function in consolidation of the cell plate, rather than in spatial guidance of its growth toward the PPB site at the cell surface.