bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy-scalable temporal cleaning device for femtosecond laser pulses based on cross-polarized wave generation
Authors: Ricci Aurélien , Jullien Aurélie , Rousseau Jean-Philippe , Liu Yi , Houard Aurélien , Ramirez Patricia , Papadopoulos Dimitris , Pellegrina Alain , Georges Patrick , Druon Frédéric , Forget Nicolas , Lopez-Martens Rodrigo
Published: April 2013

We report on a compact energy-scalable device for generating high-fidelity femtosecond laser pulses based on spatial filtering through a hollow-core fiber followed by a nonlinear crystal for cross-polarized wave (XPW) generation. This versatile device is suited for temporal pulse cleaning over a wide range of input energies (from 0.1 to >10 mJ) and is successfully qualified on different ultrafast laser systems. Full characterization of the XPW output is presented. In particular, we demonstrate the generation of 1.6 mJ energy pulses starting from 11 mJ input pulse energy. The temporal contrast of the pulses is enhanced by more than 4 orders of magnitude. In addition, pulse shortening from 40 fs down to 15 fs Fourier-transform limit yields an overall peak-power transmission of up to 50%. This device not only serves as an integrated pulse contrast filter inside an ultrafast laser amplifier but also as a simple back-end solution for temporal post-compression of amplified pulses.
Incipient piezoelectrics and electrostriction behavior in Sn-doped Bi1/2(Na0.82K0.18)1/2TiO3 lead-free ceramics
Authors: Han Hyoung-Su , Jo Wook , Kang Jin-Kyu , Ahn Chang-Won , Won Kim Ill , Ahn Kyoung-Kwan , Lee Jae-Shin
Published: April 2013

Dielectric, ferroelectric, piezoelectric, and strain properties of lead-free Sn-doped Bi1/2(Na0.82K0.18)1/2TiO3 (BNKT) were investigated. A crossover from a nonergodic relaxor to an ergodic relaxor state at room temperature, accompanied by a giant electric-field-induced strain, was observed at 5 at. % Sn doping. Switching dynamics monitored during a bipolar poling cycle manifested that the observed giant strain originates from incipient piezoelectricity. When Sn doping level reached 8 at. %, BNKT exhibited an electrostrictive behavior with a highly temperature-insensitive electrostrictive coefficient of Q11 = 0.023 m4 C−2.
Applications oriented design of Bi3+ doped phosphors
Authors: Wang Lili , Lv Zhifan , Kang Wukui , Shangguan Xinyang , Shi Jinsheng , Hao Zhihui
Published: April 2013

Based on the relationships between Bi3+ energy levels and environmental factor he in phosphors established before, positions of A band of Bi3+ in ZnWO4 and CdWO4 are predicted to lie in near ultraviolet region. ZnWO4:Bi3+ and CdWO4:Bi3+ were prepared via a precipitation method. By examining their photoluminescence, it was confirmed that Bi3+ 1S0-3P1 transition are located around 340 and 350 nm, matching well with predicted results, 357 nm and 377 nm, respectively. The emission spectra indicate that they can be effectively excited by 340 and 350 nm ultraviolet light, exhibiting a satisfactory green performance (560 and 537 nm), according with ultraviolet chip.
Molecular adsorption on silicon (001): A systematic evaluation of size effects in slab and cluster models
Authors: Tracey D. F. , Delley B. , McKenzie D. R. , Warschkow O.
Published: April 2013

First-principles calculations are in wide use today to describe chemical processes occurring on the silicon (001) surface. The number of atoms that can be explicitly treated is limited and hence size-constraints are invariably required;this applies to both cluster and periodic slab approaches. Using a trial set of seven molecular adsorbateconfigurations, we examine the dependence of calculated adsorption energies on several size parameters, namely thickness and in-plane unit cell size for slab models, as well as thickness, length, and width for cluster models. Size-converged adsorption energies are estimated by extrapolation, and are used to assess the accuracy of the more typically-sized slabs and clusters in common use today. Use of a DFT method that can be applied to both slabs and clusters allows us to assess the performance of these two approaches on an equal footing.
Evaluation of a degradable time-release mechanism for telemetry collars
Authors: Thalmann Samuel
Published: April 2013

The development of techniques to minimise impact on study animals is essential to alleviate animal welfare concerns. Reducing the potentially negative impacts from the attachment of telemetry devices is a key consideration in this area. The corrosive effect when copper, magnesium alloy and brass are connected through water acting as an electrolyte oxidises the magnesium alloy. I tested a range of magnesium washers as part of a light-weight, time-programmable, time-release mechanism fitted to telemetry collars to ensure that devices do not remain on indefinitely. Six of the eight washers in the trial corroded and released the collar between 71 and 191 days. This mechanism has potential application to a wide variety of mammals and telemetry research projects.
Young females’ sexual self-efficacy: associations with personal autonomy and the couple relationship
Authors: Zimmer-Gembeck Melanie J.
Published: April 2013

Background
Theory suggests that young women’s own efficacy for sexual self-protective behaviour is greater when they are more advanced in their cognitive autonomy, and when they have romantic partners who support autonomy rather than engage in coercive behaviours and are warm and accepting rather than rejecting. Methods: A total of 199 women (aged 16 to 25 years) completed questionnaires measuring sexual self-efficacy, autonomy, partner communication and their partners’ behaviours. Hypotheses were tested with structural equation modelling. Results: Correlations showed that young women reported more self-efficacy when they had greater autonomy and reported partners to be more supportive and warmer, and less coercive and rejecting. In structural equation modelling, the association of women’s autonomy with sexual self-efficacy was indirect via their perceived capacity to communicate with their partners. Associations of partner behaviours with sexual self-efficacy were both direct and indirect via the capacity to communicate. Conclusions: Sexual efficacy is enhanced among young women who report a greater general capacity to communicate openly with their partners and have partners who display more warmth and less rejecting behaviours. Young women are also higher in sexual self-efficacy when they report more cognitive autonomy and lower partner coercion, but these associations are completely indirect via females’ greater capacity to communicate openly. The findings provide support for sexual health programs focussing on decision-making skills, personal competence, partners’ behaviours and dyadic communication strategies.
Tertiary model of a plant cellulose synthase
Authors: Sethaphong Latsavongsakda , Haigler Candace H. , Kubicki James D. , Zimmer Jochen , Bonetta Dario , DeBolt Seth , Yingling Yaroslava G.
Published: April 2013

A 3D atomistic model of a plant cellulose synthase (CESA) has remained elusive despite over forty years of experimental effort. Here, we report a computationally predicted 3D structure of 506 amino acids of cotton CESA within the cytosolic region. Comparison of the predicted plant CESA structure with the solved structure of a bacterial cellulose-synthesizing protein validates the overall fold of the modeled glycosyltransferase (GT) domain. The coaligned plant and bacterial GT domains share a six-stranded β-sheet, five α-helices, and conserved motifs similar to those required for catalysis in other GT-2 glycosyltransferases. Extending beyond the cross-kingdom similarities related to cellulose polymerization, the predicted structure of cotton CESA reveals that plant-specific modules (plant-conserved region and class-specific region) fold into distinct subdomains on the periphery of the catalytic region. Computational results support the importance of the plant-conserved region and/or class-specific region in CESA oligomerization to form the multimeric cellulose–synthesis complexes that are characteristic of plants. Relatively high sequence conservation between plant CESAs allowed mapping of known mutations and two previously undescribed mutations that perturb cellulose synthesis in
Arabidopsis thaliana
to their analogous positions in the modeled structure. Most of these mutation sites are near the predicted catalytic region, and the confluence of other mutation sites supports the existence of previously undefined functional nodes within the catalytic core of CESA. Overall, the predicted tertiary structure provides a platform for the biochemical engineering of plant CESAs.
Millennial politics of architecture: Myths and nationhood in Budapest
Authors: Palonen Emilia
Published: April 2013

Politics in Hungary since 1989 has been focusing on nation-building. Each government has had a license to articulate what it is to be Hungarian, in the public realm with public funds. While current political debates are heated and focus yet again on defining Hungarian national identity, this article takes a distance from contemporary politics. It studies a situation ten years earlier, when the current government party Fidesz -which took a landslide victory in the 2010 general elections after eight years of socialist-liberal government - was in office for the first time from 1998 to 2002. Exploring the debate from the perspective of architecture, it reveals how Fidesz sought to mark their space and express their sense of nationhood in Budapest around the millennium. Beside publicly sponsored institutions and commemoration, architectural forms became contested as they were used to express nationality. The National Theatre, Millennium Park and House of Terror Museum, each broke with the urban flow in the left-leaning metropolis while representing the Fidesz discourse on Hungary. The article, besides analyzing postcommunist nation-building, reflects on the interconnection between architecture, politics and memory in an urban symbolic landscape. It discusses how myths of nationhood can be represented in the cityscape.
Embedding of the dunce hat
Authors: Krasinkiewicz J. , Spież S.
Published: April 2013

In this note we show that the famous Borsuk contractible non-collapsible 2-polyhedron, generally known as the dunce hat, does not embed in any product of two curves but quasi-embeds in the “three-page book”.
First Report of Gray Mold Caused by Botrytis cinerea on Greenhouse-Grown Zucchini in Korea
Authors: Cheon W. , Jeon Y. H.
Published: April 2013

In the winter of 2011, greenhouse-grown zucchini (Cucurbita pepo) in Andong City, Korea, showed severe disease symptoms on fruits and dying leaves of zucchini plants that resembled gray mold disease with about 20% yield loss. Symptoms included extensive growth of mycelia and gray conidia on stem and fruit lesions. Lesions expanded rapidly under cool, humid conditions. As the disease progressed, leaves, stems, and fruits became necrotic and were covered by an abundant, soft, gray, sporulating mycelium. Diseased fruit tissue was excised and surface sterilized by immersion in 2% NaOCl for 1 min, placed on PDA (potato dextrose agar), and incubated at 22°C. Fungal colonies were initially white and became gray to brown after 72 h. Analysis of light micrographs showed the presence of elliptical conidia on PDA that was 7.5 to 16.0 μm long and 5 to 10.5 μm wide. In culture, a few, black, small and large irregular sclerotia were produced. Microsclerotia were round, spherical or irregular in shape, and ranged from 1.0 to 3.3 and 1.2 to 3.4 mm (width and length). Conidiophores were slender and branched with enlarged apical cells bearing smooth, ash-colored conidia. These morphological characteristics identified the fungus as Botrytis cinerea (1). The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1 (forward) and ITS4 (reverse) primer set (ITS1: 5′-TCCGTAGGTGAACCTGCGG-3′, ITS4: 5′-TCCTCCGCTTATTGATATGC-3′) and sequenced (2). BLAST analysis of the PCR product showed that the sequence had 100% identity with the nucleotide sequences for B. cinerea. Pathogenicity tests were performed by placing mycelium fragments (1 cm2) of PDA cultures on zucchini fruits. Controls were treated with PDA alone. Five replicates for the inoculated and control plants were used. All fruits were covered with plastic bags and incubated in a growth chamber to maintain 90 to 100% relative humidity at 22°C. Typical symptoms appeared 2 to 6 days after inoculation. The inoculated plants developed typical gray mold symptoms with gray sporulating lesions, while controls remained healthy with no lesions. B. cinerea reisolated from the inoculated tissues was morphologically identical to the original isolates. In a cold outside (below 0°C), wet greenhouse, plants are likely to be exposed to resident Botrytis populations and if the gray mold disease occurs, it can spread on zucchini plants very fast, in 2 days to a week inside a 100 m2 greenhouse. Therefore, gray mold disease could have a significant impact on greenhouse production of zucchini. To our knowledge, this is the first report of B. cinerea causing gray mold of greenhouse-grown zucchini in Korea.

References: (1) H. L. Barnett and B. B. Hunter. Illustrated Genera of Imperfect Fungi. Burgess Publishing Company, Minneapolis, MN, 1972. (2) T. J. White et al. PCR Protocols. Academic Press, Inc., New York, 1990.
An Improved Multiplex IC-RT-PCR Assay Distinguishes Nine Strains of Potato virus Y
Authors: Chikh-Ali Mohamad , Gray Stewart M. , Karasev Alexander V.
Published: April 2013

A multiplex reverse-transcription polymerase chain reaction (RT-PCR) assay was previously developed to identify a group of Potato virus Y (PVY) isolates with unusual recombinant structures (e.g., PVYNTN-NW and SYR-III) and to differentiate them from other PVY strains. In the present study, the efficiency of this multiplex RT-PCR assay was validated and extended considerably to include five additional strains and strain groups not tested before. To make the multiplex RT-PCR assay more applicable and suitable for routine virus testing and typing, it was modified by replacing the conventional RNA extraction step with the immunocapture (IC) procedure. The results obtained using well-characterized reference isolates revealed, for the first time, that this multiplex RT-PCR assay is an accurate and robust method to identify and differentiate the nine PVY strains reported to date, including PVYO (both PVYO and PVYO-O5), PVYN, PVYNA-N, PVYNTN, PVYZ, PVYE, PVY-NE11, PVYN-Wi, and PVYN:O, which is not possible by any of the previously reported RT-PCR procedures. This would make the IC-RT-PCR procedure presented here a method of choice to identify PVY strains and assess the strain composition of PVY in a given area. The IC-RT-PCR protocol was successfully applied to typing PVY isolates in potato leaf tissue collected in the field.
Host plant-driven sensory specialization inDrosophila erecta
Authors: Linz Jeanine , Baschwitz Amelie , Strutz Antonia , Dweck Hany K. M. , Sachse Silke , Hansson Bill S. , Stensmyr Marcus C.
Published: April 2013

Finding appropriate feeding and breeding sites is crucial for all insects. To fulfil this vital task, many insects rely on their sense of smell. Alterations in the habitat—or in lifestyle—should accordingly also be reflected in the olfactory system. Solid functional evidence for direct adaptations in the olfactory system is however scarce. We have, therefore, examined the sense of smell ofDrosophila erecta, a close relative ofDrosophila melanogasterand specialist on screw pine fruits (Pandanusspp.). In comparison with three sympatric sibling species,D. erectashows specific alterations in its olfactory system towards detection and processing of a characteristicPandanusvolatile (3-methyl-2-butenyl acetate, 3M2BA). We show thatD. erectais more sensitive towards this substance, and that the increased sensitivity derives from a numerical increase of one olfactory sensory neuron (OSN) class. We also show that axons from these OSNs form a complex of enlarged glomeruli in the antennal lobe, the first olfactory brain centre, ofD. erecta. Finally, we show that 3M2BA induces oviposition inD. erecta, but not inD. melanogaster. The presumed adaptations observed here follow to a remarkable degree those found inDrosophila sechellia, a specialist upon noni fruit, and suggest a general principle for how specialization affects the sense of smell.
Disruption of the perineuronal net in the hippocampus or medial prefrontal cortex impairs fear conditioning
Authors: Hylin Michael J. , Orsi Sara A. , Moore Anthony N. , Dash Pramod K.
Published: April 2013

The perineuronal net (PNN) surrounds neurons in the central nervous system and is thought to regulate developmental plasticity. A few studies have shown an involvement of the PNN in hippocampal plasticity and memory storage in adult animals. In addition to the hippocampus, plasticity in the medial prefrontal cortex (mPFC) has been demonstrated to be critical for the storage of long-term memory, particularly memories for temporally separated events. In the present study, we examined the role of PNN in the acquisition and retention of memories for trace (in which the conditioned and unconditioned stimuli are temporally separated) and delayed (in which the conditioned and unconditioned stimuli overlap) fear conditioning in both the hippocampus and the mPFC. Consistent with a role for the hippocampus in memory storage in both delayed and trace fear conditioning, removal of hippocampal PNN disrupted contextual and trace fear memory. Disruption of the PNN in the mPFC impaired long-term trace and conditioned stimulus (CS)-elicited fear memory in the trace fear conditioning task. Interestingly, CS-elicited fear memory was also impaired when a delayed fear conditioning paradigm was used. These findings further support a role for the PNN in neural plasticity and implicate PNN-regulated plasticity in neocortical memory storage.
Altered drainage patterns in patients with melanoma and previous axillary dissection
Authors: Johnson Caitlyn , Intenzo Charles , Mastrangelo Michael J. , Feeney Kendra , Berger Adam C.
Published: April 2013

The incidence of melanoma is increasing rapidly in the United States. Sentinel lymph node biopsy is an important diagnostic tool in the treatment and staging of melanoma. However, many patients with melanoma will have had lymph node surgery for previous melanoma or breast cancer. We set out to examine alterations in drainage patterns in patients with previous axillary dissection for breast cancer. We reviewed four patients with truncal and/or extremity melanomas and examined their lymphoscintigraphy and drainage patterns. Three patients with truncal melanoma mapped to cervical lymph nodes and a fourth patient with an arm melanoma mapped to her previously dissected axilla. Sentinel lymph node mapping is still an important adjunct in patients with melanoma despite previous axillary dissection.
Relationship among antineutrophil cytoplasmic antibody, blood urea nitrogen and complement in patients with eosinophilic granulomatosis polyangiitis (Churg–Strauss syndrome)
Authors: Kawakami Tamihiro , Kimura Satoko , Takeuchi Sora , Soma Yoshinao
Published: April 2013

Eosinophilic granulomatosis with polyangiitis (EGPA), also known as Churg–Strauss syndrome, is an antineutrophil cytoplasmic antibody (ANCA)‐associated vasculitis characterized by a history of asthma, hypereosinophilia. The prevalence of ANCA in EGPA is less common than in other ANCA‐associated vasculitis. Increasing evidence of complement activation in the pathogenesis of ANCA‐associated vasculitis has been provided by studies in animal models. We examined EGPA patients with cutaneous manifestations as an initial sign and investigated the correlations among clinical, serological and histopathological findings. We focused on differences among ANCA, blood urea nitrogen and complement levels such as complement 3 (C3), C4 and total complement hemolytic activity (CH50). We retrospectively investigated the records of 22 patients (11 male and 11 female) with EGPA admitted to our hospital from 1997–2012. Ten of the 22 patients (46%) were positive for serum myeloperoxidase (MPO)‐ANCA. In contrast, all the patients were negative for serum proteinase 3 ANCA. There was a significantly positive correlation between serum CH50 and C4 levels in patients with EGPA. Serum blood urea nitrogen (BUN) levels differed significantly between MPO‐ANCA‐positive and ‐negative patients. Serum CH50 levels were higher in MPO‐ANCA‐positive patients compared to negative patients. Serum BUN levels were higher in elevated CH50 patients compared to normal and low CH50‐negative patients. We propose that positive findings for MPO‐ANCA with CH50 high activity may be a risk factor for developing renal insufficiency. Assuming there are correlations between the presence of ANCA and complements, earlier diagnosis based on initial efficacious treatment for EGPA.
Direct inversion for a fluid factor and its application in heterogeneous reservoirs
Authors: Zong Zhaoyun , Yin Xingyao , Wu Guochen
Published: April 2013

Prestack seismic inversion plays an important role in estimating elastic parameters that are sensitive to reservoirs and fluid underground. In this paper, a simultaneous inversion method named FMR‐AVA (Fluid Factor, Mu (Shear modulus), Rho (Density)‐Amplitude Variation with Angle) is proposed based on partial angle stack seismic gathers. This method can be used for direct inversion for the fluid factor, shear modulus and density of heterogeneous reservoirs. Firstly, an FMR approximation equation of a reflection coefficient is derived based on poroelasticity with P‐ and S‐wave moduli. Secondly, a stable simultaneous AVA inversion approach is presented in a Bayesian scheme. This approach has little dependence on initial models. Furthermore, it can be applied in heterogeneous reservoirs whose initial models for inversion are not easy to establish. Finally, a model test shows the superiority of this FMR‐AVA inversion method in stability and independence of initial models. We obtain a reasonable fluid factor, shear modulus and density even with smooth initial models and moderate Gaussian noise. A real data case example shows that the inverted fluid factor, shear modulus and density fit nicely with well log interpretation results, which verifies the effectiveness of the proposed method.
Managing uplands for biodiversity: Do agri‐environment schemes deliver benefits for breeding lapwing Vanellus vanellus?
Authors: Smart Jennifer , Bolton Mark , Hunter Fiona , Quayle Helen , Thomas Gavin , Gregory Richard D.
Published: April 2013

Within Europe, agri‐environment schemes are the key delivery mechanism for biodiversity conservation outside protected areas. Schemes have a range of land management options designed to deliver outcomes for target habitats or species.

Breeding waders form an important part of the biodiversity of upland grasslands, and in the UK, there are multiple land management options within agri‐environment schemes designed to benefit waders. We assessed whether such options improve the suitability of breeding habitat and population dynamics for a declining wader, the lapwing Vanellus vanellus.

The suitability of nesting and chick‐rearing habitat was better on land with agri‐environment scheme management, and breeding densities and productivity increased with habitat suitability.

The lapwing populations declined during this study, and trends did not differ between agri‐environment and non‐agri‐environment scheme land. Productivity was below that required for population stability, although there was evidence of higher productivity on agri‐environment scheme land in later years.

Agri‐environment management consisted of multiple land management options that varied in delivery of suitable habitat, breeding densities and success. The best management options were all in England on land benefiting from specific management advice or with rough grazing and grazed pasture agri‐environment scheme options.

Synthesis and applications. Despite considerable investment and positive effects of agri‐environment schemes on habitat quality, populations of lapwing in the UK uplands have declined because of inadequate productivity. For species with complex requirements, populations are only likely to increase when all of these requirements are provided. Appropriately targeted habitat management, delivered through agri‐environment schemes, can play an important role in improving habitat quality and increasing landscape diversity. However, when populations are limited by something other than habitat quality, for example, predation, then habitat management alone is unlikely to recover populations. Increasing evidence suggests that predation impacts are also likely to be important for ground‐nesting species such as lapwing. Predator management may therefore need to be integrated with habitat measures where predation is limiting breeding success and population recovery.
UK Debt in Comparative Perspective: The Pernicious Legacy of Financial Sector Debt
Authors: Thompson Helen
Published: April 2013

Research Highlights and Abstract

This article

provides a comprehensive comparative analysis of UK debt. makes a contribution to the debate on the Anglo-liberal growth model and its consequences for the recovery of the UK economy.

The UK has the highest private debt among the G7 states plus Spain. Both financial services and household debt are high. Financial services debt is much the more consequential of the two sectors. It was a central component of the growth model of the UK prior to 2008 and its legacy is making the UK's recovery from recession extremely difficult. Financial sector debt also had an impact on the UK's rising borrowing requirement from 2007. However, it was not the direct cause of the rise in the UK's budget deficit, which was in large part a product of the Brown government's approach to its political difficulties as growth came to an end. Despite the UK's high budget deficit in comparative terms, the UK has enjoyed considerable fiscal autonomy the past few years. However, this autonomy could yet be threatened by the ongoing consequences of financial sector debt.
Effect of inulin addition on the sensorial properties of reduced‐fat fresh cheese
Authors: Juan Bibiana , Zamora Anna , Quintana Felix , Guamis Buenaventura , Trujillo Antonio J
Published: April 2013

A reduced‐fat fresh cow's milk cheese with inulin (3%) was compared with both full‐fat and reduced‐fat cheeses without the prebiotic. The pH and microbiological quality of cheeses were not affected by the presence of inulin. Cheeses produced with inulin were less hard, springy, cohesive and chewy than reduced‐fat cheeses, and more similar to cheeses made from whole milk. Cheeses produced with inulin had the lowest lightness and the highest yellowness values, although these colour differences were not detected by the panellists. The sensory panel described the reduced‐fat cheese with inulin as more acceptable than its counterpart without inulin.
Designing Politics: A Neglected Justification for Political Science
Authors: Stoker Gerry
Published: April 2013

Political science offers a valuable and developing set of insights into how politics works. The challenge for the discipline, however, is that it is methodologically and culturally ill equipped to adopt a solution-oriented approach. This article makes the case for a shift in focus and points to political science work that takes the challenge of designing politics as its intellectual focus. It identifies key features of a design-oriented political science and points to examples which suggest that it is a neglected path for political science rather than an impossible road down which to travel.
Implications of time‐series gene expression profiles of replicative senescence
Authors: Kim You‐Mie , Byun Hae‐Ok , Jee Byul A. , Cho Hyunwoo , Seo Yong‐Hak , Kim You‐Sun , Park Min Hi , Chung Hae‐Young , Woo Hyun Goo , Yoon Gyesoon
Published: April 2013

Although senescence has long been implicated in aging‐associated pathologies, it is not clearly understood how senescent cells are linked to these diseases. To address this knowledge gap, we profiled cellular senescence phenotypes and mRNA expression patterns during replicative senescence in human diploid fibroblasts. We identified a sequential order of gain‐of‐senescence phenotypes: low levels of reactive oxygen species, cell mass/size increases with delayed cell growth, high levels of reactive oxygen species with increases in senescence‐associated β‐galactosidase activity (SA‐β‐gal), and high levels of SA‐β‐gal activity. Gene expression profiling revealed four distinct modules in which genes were prominently expressed at certain stages of senescence, allowing us to divide the process into four stages: early, middle, advanced, and very advanced. Interestingly, the gene expression modules governing each stage supported the development of the associated senescence phenotypes. Senescence‐associated secretory phenotype–related genes also displayed a stage‐specific expression pattern with three unique features during senescence: differential expression of interleukin isoforms, differential expression of interleukins and their receptors, and differential expression of matrix metalloproteinases and their inhibitory proteins. We validated these phenomena at the protein level using human diploid fibroblasts and aging Sprague‐Dawley rat skin tissues. Finally, disease‐association analysis of the modular genes also revealed stage‐specific patterns. Taken together, our results reflect a detailed process of cellular senescence and provide diverse genome‐wide information of cellular backgrounds for senescence.
Learning to Love Democracy: Electoral Accountability and the Success of Democracy
Authors: Svolik Milan W.
Published: April 2013

This article explains why dissatisfaction with the performance of individual politicians in new democracies often turns into disillusionment with democracy as a political system. The demands on elections as an instrument of political accountability are much greater in new than established democracies: politicians have yet to form reputations, a condition that facilitates the entry into politics of undesirable candidates who view this period as their “one‐time opportunity to get rich.” After a repeatedly disappointing government performance, voters may rationally conclude that “all politicians are crooks” and stop discriminating among them, to which all politicians rationally respond by “acting like crooks,” even if most may be willing to perform well in office if given appropriate incentives. Such an expectation‐driven failure of accountability, which I call the “trap of pessimistic expectations,” may precipitate the breakdown of democracy. Once politicians establish reputations for good performance, however, these act as barriers to the entry into politics of low‐quality politicians. The resulting improvement in government performance reinforces voters’ belief that democracy can deliver accountability, a process that I associate with democratic consolidation. These arguments provide theoretical microfoundations for several prominent empirical associations between the economic performance of new democracies, public attitudes toward democracy, and democratic stability.
Quantitative assessment of brain microvascular and tissue oxygenation during cardiac arrest and resuscitation in pigs
Authors: Yu J. , Ramadeen A. , Tsui A. K. Y. , Hu X. , Zou L. , Wilson D. F. , Esipova T. V. , Vinogradov S. A. , Leong‐Poi H. , Zamiri N. , Mazer C. D. , Dorian P. , Hare G. M. T.
Published: April 2013

Cardiac arrest is associated with a very high rate of mortality, in part due to inadequate tissue perfusion during attempts at resuscitation. Parameters such as mean arterial pressure and end‐tidal carbon dioxide may not accurately reflect adequacy of tissue perfusion during cardiac resuscitation. We hypothesised that quantitative measurements of tissue oxygen tension would more accurately reflect adequacy of tissue perfusion during experimental cardiac arrest. Using oxygen‐dependent quenching of phosphorescence, we made measurements of oxygen in the microcirculation and in the interstitial space of the brain and muscle in a porcine model of ventricular fibrillation and cardiopulmonary resuscitation. Measurements were performed at baseline, during untreated ventricular fibrillation, during resuscitation and after return of spontaneous circulation. After achieving stable baseline brain tissue oxygen tension, as measured using an Oxyphor G4‐based phosphorescent microsensor, ventricular fibrillation resulted in an immediate reduction in all measured parameters. During cardiopulmonary resuscitation, brain oxygen tension remained unchanged. After the return of spontaneous circulation, all measured parameters including brain oxygen tension recovered to baseline levels. Muscle tissue oxygen tension followed a similar trend as the brain, but with slower response times. We conclude that measurements of brain tissue oxygen tension, which more accurately reflect adequacy of tissue perfusion during cardiac arrest and resuscitation, may contribute to the development of new strategies to optimise perfusion during cardiac resuscitation and improve patient outcomes after cardiac arrest.
A 12‐year experience of the Trendelenburg perineal approach for abdominoperineal resection
Authors: Toshniwal Sumeet , Perera Marlon , Lloyd David , Nguyen Hung
Published: April 2013

Background

The abdominoperineal resection (APR) is the current accepted surgical technique for low rectal cancers. Negative circumferential surgical margins are an important prognostic indicator and are best obtained by producing a cylindrical specimen. The ‘ideal’ approach to produce such specimen is debated between a standard lithotomy position and turning the patient in the prone position in the later stages of the procedure. We aimed to assess results of perineal morbidity and oncological outcomes following the lithotomy approach at a single institution.

Methods

Data were collected retrospectively at a single institution. All patients undergoing the APR for low rectal cancers were included in the current study. Patients underwent this procedure in the standard lithotomy position and a mucocutaneous flap was not routinely used for closure of the perineal wound. The primary outcome measures in this study were local and systemic tumour recurrence and overall patient survival.

Results

Fifty‐three patients undergoing APR were included in the current study. Majority of patients (87%) received neoadjuvant therapy. Perineal morbidity was observed in 11% of patients loco‐regional recurrence occurred in 4% at 5 years. One‐, 3‐ and 5‐year survival was 87, 75 and 66%, respectively. Patients with T3/4 disease and positive circumferential surgical margins had significantly poorer survival outcomes.

Conclusion

APR can be performed in the lithotomy position with acceptable perineal morbidity and oncological safety. Negative circumferential margins can be achieved reliably by producing a cylindrical specimen with this position.
Can transabdominal ultrasound identify women at high risk for short cervical length?
Authors: Friedman Alexander M. , Schwartz Nadav , Ludmir Jack , Parry Samuel , Bastek Jamie A. , Sehdev Harish M.
Published: April 2013

Objective

To determine whether transabdominal cervical length screening could identify women at high risk for having a short cervix on transvaginal ultrasound.

Design

Retrospective cohort study.

Setting

Tertiary referral center.

Population

A total of 703 patients with a singleton pregnancy at 18 to 23+6 weeks of gestation who underwent transabdominal and transvaginal cervical length assessment during anatomy ultrasound at a single institution between January 2007 and October 2011.

Methods

Electronic medical records were reviewed to identify women who met the study criteria.

Main outcome measures

The primary outcome was the number of women with a short transabdominal cervical length (defined as ≤30 mm) who needed to undergo transvaginal ultrasound to detect one woman with a short transvaginal cervical length of ≤20 mm.

Results

In all, 703 patients were included in the primary analysis; 3.42 women with transabdominal cervical length ≤30 mm needed to undergo transvaginal ultrasound to detect one woman with transvaginal ultrasound cervical length ≤20 mm. Of women with short transvaginal cervical length ≤20 mm, 89.8% had a transabdominal measurement ≤30 mm and 96.7% had a transabdominal measurement ≤33 mm.

Conclusions

Screening of transabdominal cervical length may represent a useful strategy for detecting women with short cervix on transvaginal ultrasound.
Cowpea aphid (Aphis craccivora) associated with different host plants has different facultative endosymbionts
Authors: BRADY CRISTINA M. , WHITE JENNIFER A.
Published: April 2013

Maternally inherited facultative endosymbiotic bacteria are common among insects, including many polyphagous insect herbivores. To investigate whether symbiont infection is structured by host plant in the polyphagous aphid Aphis craccivora Koch, pyrosequencing and diagnostic PCR were performed on 26 populations from two different host plants, alfalfa (Medicago sativa) or black locust (Robinia pseudoacacia). Results indicated that Aphis craccivora harbours distinctly different microbial communities in alfalfa versus locust. The facultative symbiont Hamiltonella was found only in aphids collected from alfalfa, and the facultative symbiont Arsenophonus was found only in aphids from locust. Hamiltonella is known to protect aphids against hymenopteran parasitoids, whereas the phenotypic effects of Arsenophonus in aphids are unknown. Correspondingly, a screen of the aphid samples for hymenopteran DNA indicated that Hamiltonella‐bearing alfalfa populations of A. craccivora experienced lower parasitism than Arsenophonus‐bearing locust populations. This study contributes to the growing body of evidence that correlative associations between bacterial endosymbionts and host plants may be a common phenomenon in polyphagous herbivores, and suggests that microbial symbionts have the potential to act as drivers for observed ecological differences among host‐associated populations of polyphagous insects.
MicroRNA expression differs in cutaneous squamous cell carcinomas and healthy skin of immunocompetent individuals
Authors: Bruegger Christelle , Kempf Werner , Spoerri Iris , Arnold Andreas W. , Itin Peter H. , Burger Bettina
Published: April 2013

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers, but the influence of microRNA (miRNA) expression has only been sporadically analysed. We hypothesized that miRNAs are differentially expressed in cSCC and hence influence its development. We therefore isolated total miRNA from well‐differentiated cSCCs and from controls without SCC. Expression analyses of 12 miRNAs showed three significantly differentially expressed miRNAs. We identified a significant upregulation of the miR‐21 and the miR‐31, a proto‐oncogene like miR‐21. While the upregulated expression of miR‐21 has been known for some time, the increased expression of miR‐31 was never shown so clearly. Furthermore, we showed the upregulation of miRNA‐205, which has never been described before. The miR‐205 induces specific keratinocyte migration and could be a characteristic marker for cSCC. It has to be determined in following studies whether these upregulated expressions are specific for cSCC and if so, for which cSCC stages.
Sports Concussion and Associated Post‐Traumatic Headache
Authors: Seifert Tad D.
Published: April 2013

Despite an incidence of approximately 3.8 million sports‐related concussions per year, the pathophysiological basis of this injury remains poorly understood. Associated post‐traumatic headache, both acute and chronic, can also provide a unique treatment challenge for medical personnel. The presence of new onset or persistent headache following injury often complicates return to play decisions. It is also now evident that recurrent head trauma may be associated with the development of some chronic neurodegenerative disorders. Although anecdotal reports and consensus guidelines are utilized in the management of sports concussion and associated post‐traumatic headache, further evidence‐based data are needed. Improved prevention and management of this injury will occur with ongoing educational and research efforts. As such advances are made, it is imperative the headache specialist have continued understanding of this evolving field.
Commentary on Headache Currents Articles by Alhazzani and Goddeau
Authors: Ramadan Nabih M.
Published: April 2013

Headache is a symptom of cerebrovascular disease, particularly the hemorrhagic type. Also, certain headache types, notably migraine with aura, predispose individuals to ischemic and perhaps hemorrhagic stroke. The relationship between migraine and cerebrovascular disease can be causal, coincidental or co‐morbid.
Headache in Stroke: A Review
Authors: Goddeau Richard P. , Alhazzani Adel
Published: April 2013

Headache is a common accompanying symptom in cerebrovascular diseases. Several specific conditions and etiologies are reviewed with emphasis on distinguishing characteristics. Recognition of these conditions can help identify underlying causes of these “secondary headache syndromes” and facilitate disease‐appropriate treatment.
Acceptability of digital anal cancer screening examinations in HIV‐positive homosexual men
Authors: Read TRH , Vodstrcil L , Grulich AE , Farmer C , Bradshaw CS , Chen MY , Tabrizi S , Hocking JS , Anderson J , Fairley CK
Published: April 2013

Objectives

Anal cancer is more common in HIV‐positive homosexual men than in HIV‐negative homosexual men and the general population. Earlier diagnosis leads to improved prognosis. We aimed to determine if regular anal inspection and digital examination of asymptomatic homosexual men attending for routine HIV care were acceptable and to record the rate of referral for diagnosis of potentially malignant anal lesions.

Methods

We offered anal examinations to consecutive homosexual men with HIV infection aged ≥ 35 years during their routine HIV clinic visits, aiming to complete three examinations over a 12‐month period. Acceptability questionnaires were completed at baseline and after each examination and doctors recorded examination findings and all resulting interventions. Hospital referral outcomes were collected and interventions were costed using the Australian Medical Benefits Schedule.

Results

Of 142 men who were offered enrolment in the study, 102 [72%; 95% confidence interval (CI) 64–79%] participated. Following the initial anal examinations, four men were referred to surgeons. Cancer was excluded in three men (3%; 95% CI 1–8%) and one was diagnosed with anal squamous cell carcinoma (SCC). Three men had anoscopy performed at the time and two were referred for colonoscopy. Ninety‐eight per cent (95% CI 93–100%) of respondents said that they would probably have the examination next time. The intervention was estimated to cost approximately Australian $16 per examination.

Conclusions

Regular anal digital examinations are an acceptable and inexpensive addition to the routine care of homosexual men with HIV infection.
INCENTIVES AND THE COST OF FIRING IN AN EQUILIBRIUM LABOR MARKET MODEL WITH ENDOGENOUS LAYOFFS*
Authors: Wang Cheng
Published: April 2013

I study the effects of firing costs in an equilibrium model of the labor market with moral hazard. Layoff is an incentive device, modeled as termination of the optimal long‐term contract. When the economy’s stock of firms is fixed, firing costs could reduce layoffs and increase worker welfare. In the long run when firms are free to enter and exit the market, firing costs generate not only lower employment, longer unemployment durations, and lower aggregate output, but also lower welfare for both employed workers and new labor market entrants.
NONSTATIONARY RELATIONAL CONTRACTS WITH ADVERSE SELECTION*
Authors: Yang Huanxing
Published: April 2013

I develop a model of nonstationary relational contracts in order to study internal wage dynamics. Workers are heterogeneous, and each worker’s ability is both private information and fixed for all time. Learning therefore occurs within employment relationships. The inferences, however, are confounded by moral hazard. Incentive provision is restricted by an inability to commit to long‐term contracts. Relational contracts, which must be self‐enforcing, must therefore be used. The wage dynamics in the optimal contract, which are pinned down by the tension between incentive provision and contractual enforcement, are intimately related to the learning effect.
Glass Crystallization Research — A 36‐Year Retrospective. Part I, Fundamental Studies
Authors: Zanotto Edgar D.
Published: April 2013

Over the past 36 years, our research has mainly focused on the crystallization kinetics and properties of glasses and glass‐ceramics. A sampling of the most conclusive papers are reviewed here and include the following topics: the effects of liquid phase separation on crystal nucleation; tests and development of models of crystal nucleation, growth, and overall crystallization; metastable phase formation; surface crystallization; glass stability against devitrification; glass‐forming ability; possible correlations between the molecular structure and the nucleation mechanism; sintering with concurrent surface crystallization; and diffusional processes that control crystallization. We conclude that despite significant advancement in the knowledge about several aspects of phase transformations in glasses that resulted from our own research and of other groups, which is not described in this review, glass crystallization remains an open, rich field to be explored.
Distribution of KIR genes in Han population in Yunnan Province: comparison with other Han populations in China
Authors: Shi L. , Zhang H. , Shen Y. , Dong Y. , Li Y. , Dong Z. , Guo C. , Shi L. , Yao Y. , Yu J.
Published: April 2013

Killer cell immunoglobulin‐like receptors (KIRs) show extensive variation among different populations. In this study, 404 unrelated individuals in Han population in Yunnan Province, China, were genotyped for the presence or the absence of 16 KIR genes using the multiplex PCR‐SSP method. Our data showed that the inhibitory gene frequency of genes KIR2DL1, KIR2DL3, KIR3DL1, KIR2DL5 and KIR2DL2 was 0.930, 0.889, 0.789, 0.206 and 0.095, respectively, and the activating gene frequency of KIR2DS4, KIR3DS1, KIR2DS1, KIR2DS5, KIR2DS2 and KIR2DS3 was 0.795, 0.218, 0.196, 0.165, 0.095 and 0.087, respectively. In all, 44 distinct KIR genotypes were identified; genotype 1 was predominant with a frequency of 0.478, followed by genotypes 2 and 8 with a frequency of 0.121 and 0.077, respectively. Haplotype A outnumbered haplotype B by 2.39:1. In addition, phylogenetic tree and multidimensional scaling analysis (MDS) based on KIR genes in populations including Asian, African and Caucasians have been performed. Neighbour‐joining tree analysis and the MDS plot showed that Han populations were clustered together with Asian and were separate from other populations. The Han populations in China were separated into northern and southern groups; the Yunnan Han population investigated in this study was clustered in the southern group. These results implied that the difference between northern and southern Han populations might reflect responses to a variety of locally acting epidemiological challenges.