bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Influencing Clinically Significant Delayed Gastric Emptying After Subtotal Stomach‐Preserving Pancreatoduodenectomy
Authors: Sato Go , Ishizaki Yoichi , Yoshimoto Jiro , Sugo Hiroyuki , Imamura Hiroshi , Kawasaki Seiji
Published: October 2013

Background

Subtotal stomach‐preserving pancreatoduodenectomy (SSPPD), in which the pylorus ring is resected and most of the stomach is preserved, has been performed recently in Japan. This study was undertaken to clarify the incidence of delayed gastric emptying (DGE) after SSPPD at a high‐volume hospital and to determine the independent factors that influence the development of DGE after SSPPD.

Methods

Between 2002 and 2011, 201 consecutive patients underwent standardized SSPPD. After SSPPD, DGE (defined according to the International Study Group of Pancreatic Surgery) was analyzed, and associated variables were assessed by univariate and multivariate analyses, retrospectively.

Results

Clinically significant DGE (grades B and C) occurred in 35 (17 %) of the 201 patients; 26 patients had other accompanying abdominal complications (secondary DGE), and pancreatic leakage was the sole risk factor for DGE (odds ratio 6.63, 95 % CI 2.86–15.74; p < 0.001). Only nine (4 % of all patients) of the 35 patients with clinically significant DGE were classified as having DGE that had arisen without any obvious etiology (primary DGE).

Conclusions

DGE after SSPPD is strongly linked to the occurrence of other postoperative intra‐abdominal complications such as pancreatic fistula. The incidence rate of primary DGE after SSPPD was 4 %. Although the ISGPS classification of DGE is clearly applicable, the grades do not explain why DGE occurs. Primary and secondary DGE should therefore be defined separately.
Non‐specific accumulation of glycosphingolipids in GNE myopathy
Authors: Patzel Katherine A. , Yardeni Tal , Le Poëc‐Celic Erell , Leoyklang Petcharat , Dorward Heidi , Alonzi Dominic S. , Kukushkin Nikolay V. , Xu Bixue , Zhang Yongmin , Sollogoub Matthieu , Blériot Yves , Gahl William A. , Huizing Marjan , Butters Terry D.
Published: October 2013

Background

UDP‐GlcNAc 2‐epimerase/ManNAc 6‐kinase (GNE) is a bifunctional enzyme responsible for the first committed steps in the synthesis of sialic acid, a common terminal monosaccharide in both protein and lipid glycosylation. GNE mutations are responsible for a rare autosomal recessive neuromuscular disorder, GNE myopathy (also called hereditary inclusion body myopathy). The connection between the impairment of sialic acid synthesis and muscle pathology in GNE myopathy remains poorly understood.

Methods

Glycosphingolipid (GSL) analysis was performed by HPLC in multiple models of GNE myopathy, including patients’ fibroblasts and plasma, control fibroblasts with inhibited GNE epimerase activity through a novel imino sugar, and tissues of GneM712T/M712T knock‐in mice.

Results

Not only neutral GSLs, but also sialylated GSLs, were significantly increased compared to controls in all tested models of GNE myopathy. Treatment of GNE myopathy fibroblasts with N‐acetylmannosamine (ManNAc), a sialic acid precursor downstream of GNE epimerase activity, ameliorated the increased total GSL concentrations.

Conclusion

GNE myopathy models have increased total GSL concentrations. ManNAc supplementation results in decrease of GSL levels, linking abnormal increase of total GSLs in GNE myopathy to defects in the sialic acid biosynthetic pathway. These data advocate for further exploring GSL concentrations as an informative biomarker, not only for GNE myopathy, but also for other disorders of sialic acid metabolism.
The Effect of Pulley Reconstruction on Maximum Flexion, Bowstringing, and Gliding Coefficient in the Setting of Zone II Repair of FDS and FDP: A Cadaveric Investigation
Authors: Stanbury Spencer J. , English Christopher , Yaseen Zaneb , Reed Jeffrey D. , Chen Tony , Awad Hani , Elfar John C.
Published: October 2013

Purpose

The purpose of this experiment was to determine the effect of A2 pulley reconstruction on gliding coefficient (GC), bowstringing, and proximal interphalangeal (PIP) joint maximum flexion angle after zone II repair of flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) lacerations.

Methods

Fresh frozen cadaver forearms were mounted, and the wrist and MCP joints fixed. FDS and FDP tendons were dissected free, and sequential loads were applied while digital images were captured. The dissected digit with intact native A2 pulley, FDS, and FDP tendons was used as the control (group 1). Zone II lacerations followed by four-stranded repair of FDP plus epitendinous suture and repair of FDS were then performed, and the data recorded (group 2). A2 pulley excision and reconstruction with a loop of palmaris longus autograft was then completed and the specimens sequentially loaded and photographed (group 3). Using the digital images, GC, bowstringing, and maximum flexion angle were calculated.

Results

No difference in maximum flexion angle was observed across the three testing conditions. Zone II laceration and subsequent FDS and FDP tendon repair significantly increased the GC for group 2 specimens; however, pulley reconstruction alleviated some of this increase for group 3. Bowstringing was significantly greater after pulley reconstruction, with a mean increase of 1.9 mm at maximum flexion for group 3 specimens relative to group 1 controls.

Discussion

Strong flexor tendon repairs are needed to prevent gap formation and subsequent triggering; however, the increased bulk from these large repairs can itself produce deleterious triggering, as well as tendon abrasion. Pulley reconstruction, in the setting FDP and FDS repair (group 3), significantly reduced the GC relative to tendon repair alone (group 2). While bowstringing was significantly greater after pulley reconstruction (group 3), it averaged only 1.9 mm over group 1 specimens and did not compromise maximum flexion angle compared to the uninjured controls (group 1) or the isolated tendon repair digits (group 2).
Cells Were a More Important Foaming Factor than Free Rhamnolipids in Fermentation of Pseudomonasaeruginosa E03‐40 for High Rhamnolipid Production
Authors: Sodagari Maysam , Ju Lu‐Kwang
Published: October 2013

Rhamnolipids are among the best‐known biosurfactants. Severe foaming occurs in aerobic rhamnolipid fermentation and negatively affects operation and economics of the biosurfactant production. In this study the foaming properties were examined with samples taken along a Pseudomonas aeruginosa fermentation that produced 55 g l−1 rhamnolipids with a maximum volumetric productivity of 0.080 g l−1 h−1 and a maximum specific productivity of 0.013 g g−1 h−1. For a better understanding of the process, the broth samples were also centrifuged to prepare cell‐free supernatants and cell suspensions in water, and all samples were evaluated under fixed foaming conditions. In addition to the time profiles of foam rise, the initial foaming rates and maximum foam volumes were determined. Contrary to the general assumption, the cells, not rhamnolipids, were the main foaming agents in the fermentation. Soluble components including rhamnolipids had secondary roles. Supernatant foaming was higher after the culture entered the rhamnolipid‐producing stationary phase; however, the foaming appeared to decrease with increasing rhamnolipid concentrations at high concentrations (>15 g l−1). The pH effects on foaming of broths, supernatants, and cell suspensions were also studied. Broth foaming was 55 and 80 % less at pH 5.5 and 5.0, respectively, compared to that at pH 6.5. Cell growth and rhamnolipid production at lower pH should be included in future studies. In addition, strain selection or genetic engineering and medium modification to reduce cell hydrophobicity are suggested as useful strategies to address the foaming issue of rhamnolipid fermentation.
Identification of Distinct Monocyte Phenotypes and Correlation With Circulating Cytokine Profiles in Acute Response to Spinal Cord Injury: A Pilot Study
Authors: Huang Wan , Vodovotz Yoram , Kusturiss Mary B. , Barclay Derek , Greenwald Karen , Boninger Michael L. , Coen Paul M. , Brienza David , Sowa Gwendolyn
Published: October 2013

Background

Macrophage infiltration to the injury site during the acute response to traumatic spinal cord injury (SCI) is not uniform. Macrophage phenotype has been characterized as either proinflammatory (M1) or anti‐inflammatory (M2). Results of animal studies suggest that M1 or M2 dominance at the site of injury relates to spontaneous recovery after SCI.

Objective

To investigate whether the phenotype of circulating macrophage precursors‐monocytes (MO) is altered in the acute phase of SCI and corresponds to circulating inflammatory cytokines.

Study Design

A prospective observational cohort study.

Setting

A single academic medical center in Pennsylvania.

Patients

A cohort of 27 subjects with complete or incomplete traumatic SCI enrolled within 7 days after SCI injury.

Methods

The MO phenotype was defined within the first week after SCI by using flow cytometry and was compared with that of historic uninjured controls. Concentrations of 25 cytokines and/or chemokines were assessed by using Luminex in serial blood samples up to 2 weeks after SCI. An analysis of variance was used to determine the correlations between the phenotypes and the cytokine profiles.

Results

Patient subsets were identified with either M1‐ or M2‐dominant circulating MOs distinct from the uninjured controls. The M1 dominant was associated with higher circulating levels of proinflammatory mediators interleukin (IL)12p70 and interferon gamma‐induced protein 10 kDa (IP‐10/CXCL10), and lower levels of anti‐inflammatory cytokines IL‐10, IL‐15, and IL‐7, whereas the M2 dominant exhibited the opposite cytokine profiles with significantly higher IL‐10 and IL‐7.

Conclusion

In the acute phase after SCI, at comparable injury severity, subgroups of patients exhibit distinct M1 or M2 MOs dominance and the phenotype is correlated with M1‐ or M2‐specific cytokine and/or chemokine profiles. Although further studies are needed to determine how these observed phenotypic differences relate to functional recovery, our findings (1) provide the first evidence, to our knowledge, that indicates the possible individual differences in the immune responses to the comparable traumatic SCI, with potential implications for management of acute SCI and rehabilitation; and (2) may represent easily accessible biomarkers with prognostic utility.
Wilderness Medical Society Practice Guidelines for the Prevention and Treatment of Heat-Related Illness
Authors: Lipman Grant S. , Eifling Kurt P. , Ellis Mark A. , Gaudio Flavio G. , Otten Edward M. , Grissom Colin K.
Published: October 2013

The Wilderness Medical Society (WMS) convened an expert panel to develop a set of evidence-based guidelines for the recognition, prevention, and treatment of heat-related illness. We present a review of the classifications, pathophysiology, and evidence-based guidelines for planning and preventive measures as well as best-practice recommendations for both field- and hospital-based therapeutic management of heat-related illness. These recommendations are graded based on the quality of supporting evidence and the balance between the benefits and risks or burdens for each modality.
Akaoraora'ia te peu ‘ā to ‘ui tūpuna: Culturally Responsive Pedagogy for Cook Islands Secondary School Physical Education
Authors: Te Ava Aue , Rubie-Davies Christine , Airini  , Ovens Alan
Published: October 2013

This research examines outcomes from introducing cultural values into Cook Islands secondary schools during two cycles of action research comprising planning, implementing, observing and reflecting. The cultural values upon which the physical education lessons were based were: tāueue (participation), angaanga kapiti (cooperation), akatano (discipline), angaanga taokotai (community involvement), te reo Maori Kuki Airani (Cook Islands Maori language), and auora (physical and spiritual wellbeing). The cultural values were believed to be an essential element of teaching physical education but one challenge was how to assist teachers to implement the cultural values into classroom teaching as most participant teachers were not Cook Islanders. Findings from this action research project suggest that while participant teachers and community cultural experts may agree to incorporate cultural values in teaching Cook Islands secondary school students, teachers nonetheless find difficulties in implementing this objective.
Effect of the interaction of seaweed extracts containing laminarin and fucoidan with zinc oxide on the growth performance, digestibility and faecal characteristics of growing piglets
Authors: O'Shea C. J. , McAlpine P. , Sweeney T. , Varley P. F. , O'Doherty J. V.
Published: October 2013

Seaweed extracts (SWE) rich in laminarin and fucoidan have shown promise as a supplement for weaned piglets. However, successful application in pig nutrition depends on their bioactivity in the presence of additives such as ZnO. In the present study, a 2 × 2 factorial experiment was carried out to investigate the effect of the interaction between SWE and ZnO on the growth performance, digestibility and faecal characteristics of 192 weaned piglets (6·5 kg). The piglets were penned in groups of 4 (n 12 pens). The study consisted of two phases after weaning: a starter diet period from the day of weaning (0 d) to 21 d and a transition diet period from 21 to 40 d. The dietary treatments were as follows: (1) control diet; (2) control diet+ZnO; (3) control diet+SWE; (4) control diet+ZnO+SWE. Diets containing ZnO improved the faecal consistency of the piglets throughout the experimental period (0–40 d). An effect of the interaction between ZnO and SWE on several variable was observed. The diet containing only SWE or ZnO improved the feed conversion efficiency of the piglets during the transition diet period; however, this effect was not observed when the diet containing both ZnO and SWE was fed. The diet containing only SWE increased the N and organic matter digestibility of the piglets; however, this effect was not observed in the presence of ZnO. An interaction between ZnO and SWE was observed, whereby the faecal counts of Escherichia coli were decreased when piglets were fed the diet containing only SWE, but not when fed the diet containing both SWE and ZnO. In summary, SWE and ZnO improve growth performance when given alone, but not when given in combination. The biological effect of SWE on selected digestibility and faecal characteristics was markedly different when compared with that of ZnO.
Waves in a dusty plasma over the illuminated part of the Moon
Authors: POPEL S. I. , MORFILL G. E. , SHUKLA P. K. , THOMAS H.
Published: October 2013

Waves in a dusty plasma over the lunar dayside are considered. It is shown that the relative motion of the solar wind with respect to the photoelectrons over the lunar surface leads to the excitation of high-frequency oscillations with frequencies in the range of Langmuir and electromagnetic waves. The dust acoustic wave excitation is possible in the vicinity of the lunar terminator.
Dust shear Alfvén solitary structures in an opposite polarity dust medium
Authors: MAMUN A. A.
Published: October 2013

The basic features of dust shear Alfvén (DSA) solitary structures formed in an opposite polarity dust medium (containing positively and negatively charged dust fluids) have been investigated by using the reductive perturbation method. The derivative nonlinear Shrödinger equation and its stationary solitary wave solution are obtained for this investigation. It is shown that the opposite polarity dust medium under consideration supports the compressive DSA solitary structures having new features with new time and length scales. The implications of our results in space environments and laboratory devices are briefly discussed.
A co-invasive microsporidian parasite that reduces the predatory behaviour of its hostDikerogammarus villosus(Crustacea, Amphipoda)
Authors: BACELA-SPYCHALSKA K. , RIGAUD T. , WATTIER R. A.
Published: October 2013

Parasites are known to affect the predatory behaviour or diet of their hosts. In relation to biological invasions, parasites may significantly influence the invasiveness of the host population and/or mediate the relationships between the invader and the invaded community.Dikerogammarus villosus, a recently introduced species, has had a major impact in European rivers. Notably, its high position in trophic web and high predatory behaviour, have both facilitated its invasive success, and affected other macroinvertebrate taxa in colonized habitats. The intracellular parasiteCucumispora dikerogammari, specific toD. villosus, has successfully dispersed together with this amphipod. Data presented here have shown thatD. villosusinfected by this parasite have a reduced predatory behaviour compared with healthy individuals, and are much more active suggesting that the co-invasive parasite may diminish the predatory pressure ofD. villosuson newly colonized communities.
Use of pigs as a potential model for research into dietary modulation of the human gut microbiota
Authors: Heinritz Sonja N. , Mosenthin Rainer , Weiss Eva
Published: October 2013

The human intestinal microbial ecosystem plays an important role in maintaining health. A multitude of diseases including diarrhoea, gastrointestinal inflammatory disorders, such as necrotising enterocolitis (NEC) of neonates, and obesity are linked to microbial composition and metabolic activity. Therefore, research on possible dietary strategies influencing microbial composition and activity, both preventive and curative, is being accomplished. Interest has focused on pre- and probiotics that stimulate the intestinal production of beneficial bacterial metabolites such as butyrate, and beneficially affect microbial composition. The suitability of an animal model to study dietary linked diseases is of much concern. The physiological similarity between humans and pigs in terms of digestive and associated metabolic processes places the pig in a superior position over other non-primate models. Furthermore, the pig is a human-sized omnivorous animal with comparable nutritional requirements, and shows similarities to the human intestinal microbial ecosystem. Also, the pig has been used as a model to assess microbiota–health interactions, since pigs exhibit similar syndromes to humans, such as NEC and partly weanling diarrhoea. In contrast, when using rodent models to study diet–microbiota–health interactions, differences between rodents and humans have to be considered. For example, studies with mice and human subjects assessing possible relationships between the composition and metabolic activity of the gut microbiota and the development of obesity have shown inconsistencies in results between studies. The present review displays the similarities and differences in intestinal microbial ecology between humans and pigs, scrutinising the pig as a potential animal model, with regard to possible health effects.
The effects of dietary nitrate on blood pressure and endothelial function: a review of human intervention studies
Authors: Hobbs Ditte A. , George Trevor W. , Lovegrove Julie A.
Published: October 2013

Evidence has accumulated in recent years that suggests that nitrate from the diet, particularly vegetables, is capable of producing bioactive NO in the vasculature, following bioconversion to nitrite by oral bacteria. The aim of the present review was to consider the current body of evidence for potential beneficial effects of dietary nitrate on blood pressure and endothelial function, with emphasis on evidence from acute and chronic human intervention studies. The studies to date suggest that dietary nitrate acutely lowers blood pressure in healthy humans. An inverse relationship was seen between dose of nitrate consumed and corresponding systolic blood pressure reduction, with doses of nitrate as low as 3 mmol of nitrate reducing systolic blood pressure by 3 mmHg. Moreover, the current studies provide some promising evidence on the beneficial effects of dietary nitrate on endothelial function.In vitrostudies suggest a number of potential mechanisms by which dietary nitrate and its sequential reduction to NO may reduce blood pressure and improve endothelial function, such as: acting as a substrate for endothelial NO synthase; increasing vasodilation; inhibiting mitochondrial reactive oxygen species production and platelet aggregation. In conclusion, the evidence for beneficial effects of dietary nitrate on blood pressure and endothelial function is promising. Further long-term randomised controlled human intervention studies assessing the potential effects of dietary nitrate on blood pressure and endothelial function are needed, particularly in individuals with hypertension and at risk of CVD.
Sarcopenia: a clinical review
Authors: Cruz-Jentoft AJ
Published: October 2013

Although sarcopenia has been used to define muscle mass loss in older subjects, muscle mass is not directly linked to muscle function. Recent definitions consider sarcopenia as a syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes, such as physical disability, poor quality of life, and death. It is closely linked with physical frailty, and also with other muscle wasting disorders, including cachexia and malnutrition. This review focuses on the incorporation of sarcopenia into clinical practice, reviews case finding and diagnosis of sarcopenia, proposes a syndromic approach for the diagnostic work-up of sarcopenic patients, and looks at intervention trials with physical exercise and nutrition, as drugs to treat this condition are not expected to be available in the near future.
Corruption and the Bureaucratic Elite in Pakistan: The 1960s and 1970s Revisited
Authors: NIAZ ILHAN
Published: October 2013

The present paper examines the growth of corruption in Pakistan in the 1960s and 1970s with particular emphasis on the factors that influenced changes in the behavioural norms of the officer cadres or higher bureaucracy of Pakistan. The main argument is that during the 1960s increases in development spending and the manipulation of local governments by civil servants to help the Ayub Khan military regime secure legitimacy led to a substantial increase in the level of corruption. However, while the increase was alarming, the higher bureaucracy was still fairly clean and, given leadership, training and resources, in a position to contain the spread of corruption. In the 1970s the first Pakistan People's Party government enacted a number of reforms aimed at asserting political control over the civilian bureaucracy while pursuing a socialistic development model that justified nationalisation of industrial and commercial assets. These substantially undermined the ability of the higher bureaucracy to fight back against corruption while dramatically increasing state penetration of society and the economy, thus making opportunities for corruption more abundant. After General Zia-ul Haq's military coup in July 1977, the new regime, though it received plenty of good advice, was not interested in enhancing the autonomy and prestige of the services as that would diminish Zia's personal power over the state apparatus.
Pathways to practice: praxiography and international politics
Authors: Bueger Christian
Published: October 2013

Political scientists have started to focus on ‘practice’ as the smallest unit of analysis. Following a broader turn in the social sciences, the practice focus provides multiple advantages, including better conceptualizations of short-term social change, getting closer to the everyday activities of those speaking, writing and doing politics, appropriate conceptualization of agency-structure dynamics, or forms of analysis resonating with other communities than scholarly ones. This contribution asks what the methodological implications of the practice turn are. It is argued that the practice focus does not only imply a certain ‘theory’ but also a certain methodology. I advance the term praxiography to speak about the forms of analysis produced by practice researchers. I discuss key guidelines of praxiographic research on two levels: first, general research strategies that provide empirical access points, second, guidelines for data collection in the frame of participant observation, expert interviews, and document analysis. I conclude in arguing that although praxiography is context driven, and hence requires to be tailored to the research problem, it is vital to reflect on the methodological repertoire of praxiographic research.
Species matter: the role of competition in the assembly of congeneric bacteria
Authors: Koeppel Alexander F , Wu Martin
Published: October 2013

Interspecific competition is an important driver of community assembly in plants and animals, but phylogenetic evidence for interspecific competition in bacterial communities has been elusive. This could indicate that other processes such as habitat filtering or neutral processes are more important in bacterial community assembly. Alternatively, this could be a consequence of the lack of a consistent and meaningful species definition in bacteria. We hypothesize that competition in bacterial community assembly has gone undetected at least partly because overly broad measures of bacterial diversity units were used in previous studies. First, we tested our hypothesis in a simulation where we showed that how species are defined can dramatically affect whether phylogenetic overdispersion (a signal consistent with competitive exclusion) will be detected. Second, we demonstrated that using finer-scale Operational Taxonomic Units (OTUs) (with more stringent 16S rRNA sequence identity cutoffs or based on fast-evolving protein coding genes) in natural populations revealed previously undetected overdispersion. Finally, we argue that bacterial ecotypes, diversity units incorporating ecological and evolutionary theory, are superior to OTUs for the purpose of studying community assembly.
Photon-assisted-tunneling in a coupled double quantum dot under high microwave excitation powers
Authors: Shang Runan , Li Hai-Ou , Cao Gang , Xiao Ming , Tu Tao , Jiang Hongwen , Guo Guang-Can , Guo Guo-Ping
Published: October 2013

We perform photon-assisted-tunneling (PAT) experiments on a GaAs double quantum dot device under high microwave excitation power. Photon-assisted absorption of up to 14 photons is observed, when electron temperature (>1 K) is far above the lattice temperature. Signatures of Landau-Zener-Stückelberg interference are found even in this non-equilibrium PAT spectrum. In addition, the charge state relaxation time T1∼8ns measured in this out of thermal equilibrium double quantum dot is in agreement with other previous reports.
Turbulent velocity profiles in a tilted heat pipe
Authors: Salort J. , Riedinger X. , Rusaouen E. , Tisserand J.-C. , Seychelles F. , Castaing B. , Chillà F.
Published: October 2013

In this paper, we analyze the mean velocity profile and the Reynolds shear stress in a turbulent, inclined, heat pipe. We show that the simplest version of a mixing length model is unable to reproduce the evolution of the velocity profile shape with the inclination angle ψ. An improvement of this model, taking into account some buoyancy effects, gives nice qualitative agreement with the observations. The agreement implies a low value for the gradient Richardson number Ric above which the flow is laminar. While such a low value (Ric ≃ 0.05) is surprising, we found it in agreement with published experimental data, when the information given allowed to calculate the gradient Richardson number Ri.
Multivalent ion effects on electrostatic stability of virus-like nano-shells
Authors: Javidpour Leili , Lošdorfer Božič Anže , Naji Ali , Podgornik Rudolf
Published: October 2013

Electrostatic properties and stability of charged virus-like nano-shells are examined in ionic solutions with monovalent and multivalent ions. A theoretical model based on a thin charged spherical shell and multivalent ions within the “dressed multivalent ion” approximation, yielding their distribution across the shell and the corresponding electrostatic (osmotic) pressure acting on the shell, is compared with extensive implicit Monte-Carlo simulations. It is found to be accurate for positive or low negative surface charge densities of the shell and for sufficiently high (low) monovalent (multivalent) salt concentrations. Phase diagrams involving electrostatic pressure exhibit positive and negative values, corresponding to an outward and an inward facing force on the shell, respectively. This provides an explanation for the high sensitivity of viral shell stability and self-assembly of viral capsid shells on the ionic environment.
Phase separation of binary nonadditive hard sphere fluid mixture confined in random porous media
Authors: Chen W.
Published: October 2013

I analyze the fluid-fluid phase separation of nonadditive hard sphere fluid mixture absorbed in random porous media. An equation of state is derived by using the perturbation theory to this complex system with quenched disorders. The results of this theory are in good agreement with those obtained from semi-grand canonical ensemble Monte Carlo simulations. The contact value of the fluid-fluid radial distribution functions of the reference which is the key point of the perturbation process is derived as well, the comparison against Monte Carlo simulations shows that it has an excellent accuracy.
A quantum dot single photon source driven by resonant electrical injection
Authors: Conterio M. J. , Sköld N. , Ellis D. J. P. , Farrer I. , Ritchie D. A. , Shields A. J.
Published: October 2013

We present a demonstration of single photon emission from an entirely electrically driven resonant injection quantum dot device. We selectively measure the emission from a single dot in the ensemble by tuning the applied bias so as to induce resonant tunneling into the dot. Direct injection of carriers into the dot leads to a suppression of background light, allowing us to demonstrate single photon emission from a single dot with no spectral filtering. We study the effects limiting the linewidths of photons emitted from the device.
Large rotating field entropy change in ErFeO3 single crystal with angular distribution contribution
Authors: Huang Ruoxiang , Cao Shixun , Ren Wei , Zhan Sheng , Kang Baojuan , Zhang Jincang
Published: October 2013

We report the rotating field entropy of ErFeO3 single-crystal in a temperature range of 3–40 K. The giant magnetic entropy change, ΔSM = −20.7 J/(kg K), and the refrigerant capacity, RC = 273.5 J/kg, are observed near T=6 K. The anisotropic constants at 6 K, K1 = 1.24× 103 J/kg, K2 = 0.74 × 103 J/kg, in the bc plane are obtained. By considering the magnetocrystalline anisotropy and Fermi-Dirac angular distribution along the orientation of spontaneous magnetization, the experimental results can be well simulated. Our present work demonstrates that ErFeO3 crystal may find practical use for low temperature anisotropic magnetic refrigeration.
Formation of an amorphous phase and its crystallization in the immiscible Nb–Zr system by mechanical alloying
Authors: Al-Aqeeli N. , Suryanarayana C. , Hussein M. A.
Published: October 2013

Mechanical alloying of binary Nb-Zr powder mixtures was carried out to evaluate the formation of metastable phases in this immiscible system. The milled powders were characterized for their constitution and structure by X-ray diffraction and transmission electron microscopy methods. It was shown that an amorphous phase had formed on milling the binary powder mixture for about 10 h and that it had crystallized on subsequent milling up to 50–70 h, referred to as mechanical crystallization. Thermodynamic and structural arguments have been presented to explain the formation of the amorphous phase and its subsequent crystallization.
Electrostatic solitary waves in dusty pair-ion plasmas
Authors: Misra A. P. , Adhikary N. C.
Published: October 2013

The propagation of electrostatic waves in an unmagnetized collisionless pair-ion plasma with immobile positively charged dusts is studied for both large- and small-amplitude perturbations. Using a two-fluid model for pair-ions, it is shown that there appear two linear ion modes, namely the “fast” and “slow” waves in dusty pair-ion plasmas. The properties of these wave modes are studied with different mass (m) and temperature (T) ratios of negative to positive ions, as well as the effects of immobile charged dusts (δ). For large-amplitude waves, the pseudopotential approach is performed, whereas the standard reductive perturbation technique is used to study the small-amplitude Korteweg-de Vries (KdV) solitons. The profiles of the pseudopotential, the large amplitude solitons as well as the dynamical evolution of KdV solitons, are numerically studied with the system parameters as above. It is found that the pair-ion plasmas with positively charged dusts support the propagation of solitary waves (SWs) with only the negative potential. The results may be useful for the excitation of SWs in laboratory dusty pair-ion plasmas, electron-free industrial plasmas as well as for observation in space plasmas where electron density is negligibly small compared to that of negative ions.
Dependence of silicon oxidation channel on distribution of surface electrons at initial stage of oxide growth on Si(001)
Authors: Han Han , Che J. G.
Published: October 2013

Our first principles simulations for a single oxygen atom barrierless adsorption on Si(001) show that only a few channels exist for silicon oxidation. The reason is that surface electrons reduce O's electronegativity. According to the dependence of the silicon oxidation channels on the distribution of the surface electrons, we explain at atomic level that if the narrow regions of the oxidation channels can be occupied by pre-growth, such as depositing one monolayer of Sr on the Si(001), the silicon oxidation channels can be closed and the high-quality interface between oxides and silicon can be realized.
Study on optimization model of energy collection efficiency and its power generation benefit evaluation of landfill gas
Authors: Qiang Xue , Lei Liu
Published: October 2013

An optimization model for joint biogas energy collection efficiency that targets the prediction model for landfill gas output dynamics, and the optimization model for gas well output has been established. The model was used to comprehensively analyze and evaluate the collection efficiency of a landfill gas well, together with the long-term monitoring the gas output of the gas well within Chenjiachong Landfill. The collection efficiency increased by more than 50% than the original collection of landfill biogas, and the power generation efficiency increased more than two times after the reservoir area of the landfill was optimized and regulated.
Characterization of defects in 9.7% efficient Cu2ZnSnSe4-CdS-ZnO solar cells
Authors: Brammertz G. , Buffière M. , Oueslati S. , ElAnzeery H. , Ben Messaoud K. , Sahayaraj S. , Köble C. , Meuris M. , Poortmans J.
Published: October 2013

We have fabricated Cu2ZnSnSe4-CdS-ZnO solar cells with a total area efficiency of 9.7%. The absorber layer was fabricated by selenization of sputtered Cu10Sn90, Zn, and Cu multilayers. A large ideality factor of the order of 3 is observed in both illuminated and dark IV-curves, which seems to point in the direction of complex recombination mechanisms such as recombination through fluctuating potentials in the conduction and valence bands of the solar cell structure. A potential barrier of about 135 meV in the device seems to be responsible for an exponential increase of the series resistance at low temperatures, but at room temperature, the effect of this barrier remains relatively small. The free carrier density in the absorber is of the order of 1015 cm−3 and does not vary much as the temperature is decreased.
Magnetically tunable terahertz magnetoplasmons in ferrofluid-filled photonic crystals
Authors: Fan Fei , Chen Sai , Lin Wei , Miao Yin-Ping , Chang Sheng-Jiang , Liu Bo , Wang Xiang-Hui , Lin Lie
Published: October 2013

We investigated terahertz (THz) magneto-optical properties of a ferrofluid and a ferrofluid-filled photonic crystal (FFPC) by using the THz time-domain spectroscopy. A magnetoplasmon resonance splitting and an induced THz transparency phenomenon were demonstrated in the FFPC. The further investigation reveals that the induced transparency originates from the interference between magnetoplasmon modes in the hybrid magneto-optical system of FFPC, and the THz modulation with a 40% intensity modulation depth can be realized in this induced transparency frequency band. This device structure and its tunabilty scheme will have great potential applications in THz filtering, modulation and sensing.
Surface plasmon resonances of protein-conjugated gold nanoparticles on graphitic substrates
Authors: Phan Anh D. , Hoang Trinh X. , Nghiem Thi H. L. , Woods Lilia M.
Published: October 2013

We present theoretical calculations for the absorption properties of protein-coated gold nanoparticles on graphene and graphite substrates. As the substrate is far away from nanoparticles, numerical results show that the number of protein bovine serum molecules aggregating on gold surfaces can be quantitatively determined for gold nanoparticles with arbitrary size by means of the Mie theory and the absorption spectra. The presence of a graphene substrate near the protein-conjugated gold nanoparticles results in a red shift of the surface plasmon resonances of the nanoparticles. This effect can be modulated upon changing the graphene chemical potential. Our findings show that the graphene and graphite affect the absorption spectra in a similar way.
Modern calibration and historical testing of small-area, fire-interval reconstruction methods
Authors: Dugan Alexa J. , Baker William L.
Published: October 2013

Accuracy of small-area, fire-interval estimation methods has been inadequately assessed, thus we conducted modern calibration and historical testing of the traditional composite-fire-interval and a newer all-tree-fire-interval method for estimating population mean fire intervals. We tested in eight areas, at four scales, using 30 small plots across ponderosa pine forests on the South Rim of Grand Canyon National Park. In modern calibration, individual-plot all-tree-fire-intervals were equal to population mean fire intervals in all plots. Across the eight areas, a mean-plot version of the all-tree-fire-interval method never failed, whereas mean-plot versions of composite-fire-intervals failed in 37.5–100% of areas. Pooled composite-fire-intervals, the traditional method, failed in all subareas. In historical testing, pooled and mean-plot all-tree-fire-interval methods and two variations of a mean-plot composite-fire-interval method had the lowest mean relative errors. Again, pooled composite-fire-intervals performed poorly across the eight areas. Overall, in modern and historical tests, the mean-plot all-tree-fire-interval method outperformed all others, but highly filtered mean-plot composite-fire-intervals were fairly accurate in historical tests. Both could be reliable methods, if replicated in small plots averaged over 600–1000-ha landscapes, but for small areas, the all-tree-fire-interval method outperformed others. However, for general use, there may be more value in spatially explicit, landscape-scale methods, rather than any small-area method.
Src-mediated caveolin-1 phosphorylation affects the targeting of active Src to specific membrane sites
Authors: Gottlieb-Abraham Efrat , Shvartsman Dmitry E. , Donaldson John C. , Ehrlich Marcelo , Gutman Orit , Martin G. Steven , Henis Yoav I.
Published: October 2013

Src interactions with the plasma membrane are an important determinant of its activity. In turn, Src activity modulates its association with the membrane through binding of activated Src to phosphotyrosylated proteins. Caveolin-1 (Cav-1), a major component of caveolae, is a known Src phosphorylation target, and both were reported to regulate cell transformation. However, the nature of Src-Cav-1 interactions, a potential mechanism of their coregulation, remained unclear. Here we used fluorescence recovery after photobleaching beam-size analysis, coimmunoprecipitation, quantitative imaging, and far-Western studies with cells expressing wild type, as well as structural and activity mutants of Src–green fluorescent protein and Cav-1–monomeric red fluorescent protein, to measure their interactions with the membrane and with each other. We show dynamic Src–plasma membrane interactions, which are augmented and stabilized by Cav-1. The mechanism involves phosphorylation of Cav-1 at Tyr-14 by Src and subsequent binding of the Src SH2 domain to phospho–Cav-1, leading to accumulation of activated Src in focal adhesions. This novel Cav-1 function potentially modulates focal adhesion dynamics.
gCMAP: user-friendly connectivity mapping with R
Authors: Sandmann Thomas , Kummerfeld Sarah K. , Gentleman Robert , Bourgon Richard
Published: October 2013

Connections between disease phenotypes and drug effects can be made by identifying commonalities in the associated patterns of differential gene expression. Searchable databases that record the impacts of chemical or genetic perturbations on the transcriptome—here referred to as ‘connectivity maps’—permit discovery of such commonalities. We describe two R packages, gCMAP and gCMAPWeb, which provide a complete framework to construct and query connectivity maps assembled from user-defined collections of differential gene expression data. Microarray or RNAseq data are processed in a standardized way, and results can be interrogated using various well-established gene set enrichment methods. The packages also feature an easy-to-deploy web application that facilitates reproducible research through automatic generation of graphical and tabular reports.

Availability and implementation: The gCMAP and gCMAPWeb R packages are freely available for UNIX, Windows and Mac OS X operating systems at Bioconductor (http://www.bioconductor.org).

Contact:  bourgon.richard@gene.com

Supplementary information:  Supplementary data are available at Bioinformatics online.
The ionized nebula surrounding the red supergiant W26 in Westerlund 1
Authors: Wright Nicholas J. , Wesson Roger , Drew Janet E. , Barentsen Geert , Barlow Michael J. , Walsh Jeremy R. , Zijlstra Albert , Drake Jeremy J. , Eislöffel Jochen , Farnhill Hywel J.
Published: October 2013

We present Hα images of an ionized nebula surrounding the M2-5Ia red supergiant (RSG) W26 in the massive star cluster Westerlund 1. The nebula consists of a circumstellar shell or ring ∼0.1 pc in diameter and a triangular nebula ∼0.2 pc from the star that in high-resolution Hubble Space Telescope images shows a complex filamentary structure. The excitation mechanism of both regions is unclear since RSGs are too cool to produce ionizing photons and we consider various possibilities. The presence of the nebula, high stellar luminosity and spectral variability suggests that W26 is a highly evolved RSG experiencing extreme levels of mass-loss. As the only known example of an ionized nebula surrounding an RSG W26 deserves further attention to improve our understanding of the final evolutionary stages of massive stars.
Sagittal Alignment of Spine and Spinal Cord for Upper Cervical Irreducible Atlantoaxial Kyphosis in Elderly Patients
Authors: Sasao Yutaka , Kojima Atsushi , Torii Yoshiaki , Morioka Shigeta , Fujii Atsushi , Aoki Haruhito
Published: October 2013

Study Design:

Retrospective study.

Objective:

To evaluate clinical and radiographic outcome of posterior decompression and occipito-cervical/thoracic (OCT) fusion in patients with irreducible atlantoaxial kyphosis (IAK).

Summary of Background Data:

Posterior OCT fusion is an effective surgical procedure for treating IAK in the elderly. However, it is unclear whether correction can be obtained by the strong corrective force provided by implants, even in patients in whom reduction cannot be obtained preoperatively. There are no reports of improvement in patients in whom correction could not be achieved by a rigid system.

Methods:

Twenty-five patients with IAK with mild vertical subluxation due to rheumatoid arthritis and 3 patients with IAK due to os odontoideum were treated with fossa magnum decompression, C1 laminectomy and OCT fusion.

Results:

Mean follow-up period was 4.2 years. Preoperative and postoperative neurological findings revealed improvement by 1 or more grades in 18 of 28 (64.2%) patients. The parameters of spinal alignment, sagittal spinal cord alignment, and basilar invagination were evaluated on radiographs. No significant difference between preoperative and postoperative status was seen for the clivo-axial angle, occipito-upper cervical angle, atlantodental interval, or occipito-cervical 2 angle, whereas significant improvement was seen in the cervico-medullary and dorsal CM angles (both P<0.05). No significant postoperative change in the vertical direction was seen for any of the parameters. Width of the spinal cord at the C1 level was significantly increased postoperatively, with a significant expansion of the cerebral spinal fluid space at the same level (P<0.05).

Conclusions:

Posterior decompression with fusion for the treatment of IAK in the elderly did not produce significant change in spinal alignment, but did significantly improve spinal cord alignment and local spinal cord compression at the C1 level, achieving satisfactory clinical outcomes.
Cost-Effectiveness Analysis of Percutaneous Vertebroplasty for Osteoporotic Compression Fractures
Authors: Takura Tomoyuki , Yoshimatsu Misako , Sugimori Hiroki , Takizawa Kenji , Furumatsu Yoshiyuki , Ikeda Hirotaka , Kato Hiroshi , Ogawa Yukihisa , Hamaguchi Shingo , Fujikawa Atsuko , Satoh Toshihiko , Nakajima Yasuo
Published: October 2013

Study Design:

Single-center, single-arm, prospective time-series study.

Objective:

To assess the cost-effectiveness and improvement in quality of life (QOL) of percutaneous vertebroplasty (PVP).

Summary of Background Data:

PVP is known to relieve back pain and increase QOL for osteoporotic compression fractures. However, the economic value of PVP has never been evaluated in Japan where universal health care system is adopted.

Methods:

We prospectively followed up 163 patients with acute vertebral osteoporotic compression fractures, 44 males aged 76.4±6.0 years and 119 females aged 76.8±7.1 years, who underwent PVP. To measure health-related QOL and pain during 52 weeks observation, we used the European Quality of Life–5 Dimensions (EQ-5D), the Rolland-Morris Disability Questionnaire (RMD), the 8-item Short-Form health survey (SF-8), and visual analogue scale (VAS). Quality-adjusted life years (QALY) were calculated using the change of health utility of EQ-5D. The direct medical cost was calculated by accounting system of the hospital and Japanese health insurance system. Cost-effectiveness was analyzed using incremental cost-effectiveness ratio (ICER): Δ medical cost/Δ QALY.

Results:

After PVP, improvement in EQ-5D, RMD, SF-8, and VAS scores were observed. The gain of QALY until 52 weeks was 0.162. The estimated lifetime gain of QALY reached 1.421. The direct medical cost for PVP was ¥286,740 (about 3061 US dollars). Cost-effectiveness analysis using ICER showed that lifetime medical cost for a gain of 1 QALY was ¥201,748 (about 2154 US dollars). Correlations between changes in EQ-5D scores and other parameters such as RMD, SF-8, and VAS were observed during most of the study period, which might support the reliability and applicability to measure health utilities by EQ-5D for osteoporotic compression fractures in Japan as well.

Conclusions:

PVP may improve QOL and ameliorate pain for acute osteoporotic compression fractures and be cost-effective in Japan.