bluuebunny/crossref_metadata_2025 huggingface dataset:
Electro-optically cavity dumped 2 μm semiconductor disk laser emitting 3 ns pulses of 30 W peak power
Authors: Kaspar Sebastian , Rattunde Marcel , Töpper Tino , Schwarz Ulrich T. , Manz Christian , Köhler Klaus , Wagner Joachim
Published: October 2012

A 2 μm electro-optically cavity-dumped semiconductor disk laser (SDL) with a pulse full width at half maximum of 3 ns, a pulse peak power of 30 W, and repetition rates adjustable between 87 kHz and 1 MHz is reported. For ns-pulse cavity dumping the SDL was set up with a 35-cm long cavity into which an intra-cavity Brewster-angled polarizer prism and a Pockels cell for rotation of the linear polarization were inserted. By means of internal total reflection in the birefringent polarizer, pulses are coupled out of the cavity sideways. This variant of ns-pulse 2-μm SDL is well suited for applications such as high-precision light detection and ranging or ns-pulse laser materials processing after further power amplification.
Two-dimensional distributed-feedback in InGaAs/GaAs quantum structure lattice arrays
Authors: Cheng K. Y. , Cheng Chien-Chia , Hsieh K. C.
Published: October 2012

The spontaneous emission properties of an artificial semiconductor lattice—quantum structure lattice (QSL)—with in-plane two-dimensional distributed-feedback (DFB) are reported. Quantum box arrays fabricated in strained InGaAs/GaAs quantum wells are used as lattice units in the QSL. The photoluminescence (PL) peak wavelength of the QSL shows the characteristic weak temperature dependence of a DFB structure (0.024 nm/K) between 77 and 150 K. The surface emission of the QSL array shows a collimated radiation pattern. The peak PL intensity has maximum values centered within ±30° of the surface normal and dropped off beyond that angle rapidly.
Effect of a pre-freezing treatment with cholesterol-loaded cyclodextrins on boar sperm longevity, capacitation dynamics, ability to adhere to porcine oviductal epithelial cells in vitro and DNA fragmentation dynamics
Authors: Tomás C. , Blanch E. , Fazeli A. , Mocé E.
Published: October 2012

The aim of this work was to examine how a pre-freezing treatment with cholesterol-loaded cyclodextrins (CLC) affects boar sperm longevity, capacitation dynamics, ability to bind to a porcine telomerase-immortalised oviductal epithelial cell line (TERT-OPEC) in vitro and DNA integrity dynamics after freeze–thawing. Although the samples treated with CLC exhibited lower sperm quality than the control samples (P < 0.05) immediately after thawing, these differences disappeared (P > 0.05) after long-term incubation (26 h at 37 or 16°C). Additionally, the CLC-treated spermatozoa underwent similar capacitation and DNA fragmentation dynamics as the control spermatozoa (P > 0.05). However, CLC-treated spermatozoa were better able to bind to TERT-OPEC in vitro (P < 0.0001). In conclusion, the pre-freezing treatment of boar spermatozoa with CLC enhanced the ability of the spermatozoa to bind to TERT-OPEC in vitro, which could have an effect on the establishment of the sperm reservoir in the ampullary­–isthmic junction in vivo. Additionally, frozen–thawed spermatozoa can be stored at 16°C for at least 6 h without a significant observable decline in sperm quality, which could be beneficial for the transport of thawed diluted doses of spermatozoa from the laboratory to the farm.
Reducing the stigma of herpes simplex virus infection: lessons from an online video contest
Authors: Shearer Lee S. , Simmons Lisa , Mindel Adrian , Stanberry Lawrence R. , Rosenthal Susan L.
Published: October 2012

Background Herpes simplex virus (HSV) is one of the most common sexually transmisible infections worldwide. HSV-associated stigma negatively impacts emotional and sexual health, suggesting a need for novel approaches to reducing stigma. The aims of this study were to describe the range of destigmatising strategies used by the public in brief online videos, and to describe videos that were successful or unsuccessful in creating a destigmatising message. Methods: A thematic content analysis was performed on 103 publicly produced YouTube videos designed to destigmatise HSV infection for an Australian online contest. Results: Five destigmatising strategies were identified: providing information, normalising through familiarity, promoting disclosure, negating a negative perception and expressing moral indignation. Most videos employed multiple strategies. Regarding the degree of destigmatisation achieved, videos were coded as unsuccessful, successful, mixed or neutral. Unsuccessful and successful videos often employed the same strategies, but differed in their ability to balance positive and negative messages about HSV and to manage affective content. Some videos were successful despite not providing information about HSV. Mixed videos were appreciated differently in different contexts, and the use of humour was especially problematic. Neutral videos tended to exclusively provide information while avoiding affective content. Conclusions: Efforts to reduce HSV-associated stigma may be unsuccessful and may even perpetuate stigma. Special attention must be paid to balance and to affective content, specifically humour, when attempting to convey a destigmatising message. Doing so may help reduce the role stigma plays as a barrier to appropriate care for patients with HSV infection.
INTERGENERATIONAL HELP AND PUBLIC ASSISTANCE IN EUROPE
Authors: Brandt Martina
Published: October 2012

The comparative analysis of intergenerational support patterns based on SHARE, the Survey of Health, Ageing, and Retirement in Europe, with about 30,000 respondents from 11 European countries reveals a distinct geographical distribution of private support patterns: in Northern Europe help between parents and children is very common, but typically little time-consuming. The contrary is true for Southern Europe, where comparably few support relations are very intense in terms of time. Central Western Europe lies in-between with average transfer rates and intensities. Using multilevel modeling, these different support patterns can be explained by the prevalence of public assistance according to the specialization hypothesis: with increased public transfers and social services, sporadic help is more likely (crowding in), and less time consuming support between generations (crowding out) occurs. Accordingly, most support is provided voluntarily in Northern Europe, whereas it is more often perceived as obligatory in Continental and Mediterranean countries.
Outbreak of Mycobacterium mucogenicum Bloodstream Infections among Patients with Sickle Cell Disease in an Outpatient Setting
Authors: Ashraf Muhammad Salman , Swinker Marian , Augustino Kerri L. , Nobles Delores , Knupp Charles , Liles Darla , Christie John , Ramsey Keith M.
Published: October 2012

Objective.

To study an outbreak of Mycobacterium mucogenicum bloodstream infections in an outpatient setting.

Design.

Outbreak investigation and retrospective chart review.

Setting.

University outpatient clinic.

Patients.

Patients whose blood cultures tested positive for M. mucogenicum in May or June 2008.

Methods.

An outbreak investigation and a review of infection control practices were conducted. During the process, environmental culture samples were obtained. Isolates from patients and the environment were genotyped with the DiversiLab typing system to identify the source. Chart reviews were conducted to study the management and outcomes of the patients.

Results.

Four patients with sickle cell disease and implanted ports followed in the same hematology outpatient clinic developed blood cultures positive for M. mucogenicum. A nurse in the clinic had prepared intravenous port flushes on the sink counter, using a saline bag that was hanging over the sink throughout the shift. None of the environmental cultures grew M. mucogenicum except for the tap water from 2 rooms, 1 of which had a faucet aerator. The 4 patient isolates and the tap water isolate from the room with the aerator were found to have greater than 98.5% similarity. The subcutaneous ports were removed, and patients cleared their infections after a course of antibiotic therapy.

Conclusion.

The source of the M. mucogenicum bacteremia outbreak was identified by genotyping analysis as the clinic tap water supply. The preparation of intravenous medications near the sink was likely an important factor in transmission, along with the presence of a faucet aerator.
Market Power Screens Willingness-to-Pay*
Authors: Weyl E. Glen , Tirole Jean
Published: October 2012

What is the best way to reward innovation? While prizes avoid deadweight loss, intellectual property (IP) selects high social surplus projects. Optimal innovation policy thus trades off the ex ante screening benefit and the ex post distortion. It solves a multidimensional screening problem in the private information held by the innovator: research cost, quality, and market size of the innovation. The appropriate degree of market power is never full monopoly pricing and is determined by measurable market characteristics, the inequality and elasticity of innovation supply, making the analysis open to empirical calibration. The framework has applications beyond IP policy to the optimal pricing of platforms or the optimal procurement of public infrastructure.
Strategic Issues for Facilities Managers
Authors: Fojt Martin
Published: October 2012

Facilities management is becoming a key issue in many organizations as change is, as Charles Handy et al. have recognized, the only way forward. Companies which remain stagnant
eventually fall behind their competitors or have change enforced on them. The latter is obviously undesirable for many reasons owing to hastily planned measures which have probably
not been properly thought through. This will have an obvious knock‐on effect to staff with potentially enormous strategic problems. Change is something we all have to get used to in order to progress and develop, and it is against this backdrop that the right type of facilities are needed to enhance the smooth transition of the change process. People normally
associate change with an organization which is shrinking or off‐loading unwanted space and facilities which are no longer any use. This would probably be quite undesirable owing to the recession‐hit 1990s in which companies either have gone into liquidation or have made radical changes to meet the demands of the modern industrial era. But successful organizations also make radical cuts in staffing and facilities. Barclays Bank, for example, cut 2,000 branch jobs in the UK during 1994 while it increased its profits by 181 per cent to £1.86bn. This controversial strategy of cutting back on staffing levels and making better use of facilities while continuing to make huge profits is quite obviously a contentious one, as many organizations are looking for “smarter” ways of working. This entails examining alternative working practices to maximize the use of current facilities.
Growth establishment and phenology of four woody Saharan species
Authors: Derbel Salma , Chaieb Mohamed
Published: October 2012

Henophyton deserti, Calligonum polygonoides, Ephedra alata and Anthyllis henoniana may be suitable Saharan species for the rehabilitation of degraded lands. In this context, the phenology, excavation of root systems and seedling establishment of these species were investigated in the southern Tunisia. Our data suggest that phenological differences between the studied species may depend on the rooting depth. The mean seedling emergence rate was 73% in H. deserti, 66% in A. henoniana, 60% in C. polygonoides and 50% in E. alata. Statistical analyses of seedling establishment showed a highly significant difference among the four species in both seasons (F = 1595.15, P < 0.0001), species (F = 781.57, P < 0.0001) and species/season interaction (F = 61.84, P < 0.0001). After 3 years, seedling mortality ranged from 73% to 89%. Seedling mortality reached a maximum in the summer of the first year of study (P < 0.001). This study provided further understanding of the ecological tolerance, adaptive strategy and the low density of these species in nature. Henophyton deserti appears to be better adapted to the harsh desert environment. These findings explain the very high density observed in the Sahara compared with other studied species. This species has therefore proven to be an excellent candidate for the ecological restoration of degraded desert rangelands and can be introduced successfully in to rehabilitation programmes.
Social Contexts and Coping Strategies of Foreign Wives in Korea: Using a Conceptual Framework of Social Identity Theory
Authors: Kim HeeJoo
Published: October 2012

This study aimed to address the social contexts of Korean society in which diverse social interactions of foreign wives take place and to identify coping strategies to construct positive social identities. Social identities are often reconstructed as a result of dynamic interactions with various situations. Using the conceptual framework of social identity theory, this study attempted to uncover the social contexts that shape foreign wives' social identities. This study, using the qualitative approach, selected nine Filipino and Vietnamese participants who were married to Korean men. The data were collected by in‐depth interviews, a focus group with three Vietnamese participants, field notes, participant observation, and photo documents. In the section on study findings, this study addressed Korean social contexts, in which Korean government has been providing a variety of multicultural policies and services for helping foreign wives successfully adapt to Korea. This study also found various forms of stereotypes and discrimination against foreign wives and presented their discrimination experiences. Diverse ways to cope with such negative experiences are presented in the last section. Given the findings, the researcher suggests that policies and programs should promote foreign wives' integration in Korean society.
Structure‐Based Identification of Aporphines with Selective 5‐HT2A Receptor‐Binding Activity
Authors: Munusamy Vani , Yap Beow Keat , Buckle Michael J. C. , Doughty Stephen W. , Chung Lip Yong
Published: October 2012

Selective blockade of the serotonin 5‐HT2A receptor is a useful therapeutic approach for a number of disorders, including schizophrenia, insomnia and ischaemic heart disease. A series of aporphines were docked into a homology model of the rat 5‐HT2A receptor using AutoDock. Selected compounds with high in silico binding affinities were screened in vitro using radioligand‐binding assays against rat serotonin (5‐HT1A and 5‐HT2A) and dopamine (D1 and D2) receptors. (R)‐Roemerine and (±)‐nuciferine were found to have high affinity for the 5‐HT2A receptor (Ki = 62 and 139 nm, respectively), with (R)‐roemerine showing 20‐ to 400‐fold selectivity for the 5‐HT2A receptor over the 5‐HT1A, D1 and D2 receptors. Investigation into the ligand–receptor interactions suggested that the selectivity of (R)‐roemerine is due to it having stronger H‐bonding and dipole–dipole interactions with several of the key residues in the 5‐HT2A receptor‐binding site.
Synthesis and Evaluation of Thiouracil Derivatives as Dipeptidyl Peptidase IV Inhibitors
Authors: Sharma Mani , Singh Divya , Gupta Monica
Published: October 2012

A series of thiouracil derivatives were designed, synthesized and screened for in vitro inhibition of dipeptidyl peptidase IV. The SAR study indicated the influence of substituted chemical modifications on thiouracil scaffold. Compounds 8 (IC50 = 0.32 μm), 9 (IC50 = 0.29 μm), and 12 (IC50 = 0.25 μm) showed excellent dipeptidyl peptidase IV inhibition having heterocyclic substituted piperazine with acetamide linker resulted as most potent dipeptidyl peptidase IV inhibitors among all the compounds screened. Single dose (10 mg/kg) of the compounds 8, 9, and 12 significantly reduced glucose excursion during oral glucose tolerance test in streptozotocin‐induced diabetic rat model. The present study on substituted thiouracil derivatives shows good‐to‐moderate inhibitory potential of dipeptidyl peptidase IV enzyme.
Caries treatment in a dental practice‐based research network: movement toward stated evidence‐based treatment
Authors: Gilbert Gregg H. , Gordan Valeria V. , Funkhouser Ellen M. , Rindal D. Brad , Fellows Jeffrey L. , Qvist Vibeke , Anderson Gerald , Worley Donald ,   The National Dental PBRN Collaborative Group
Published: October 2012

Objectives

Practice‐based research networks (PBRNs) provide a venue to foster evidence‐based care. We tested the hypothesis that a higher level of participation in a dental PBRN is associated with greater stated change toward evidence‐based practice.

Methods

A total of 565 dental PBRN practitioner‐investigators completed a baseline questionnaire entitled ‘Assessment of Caries Diagnosis and Treatment’; 405 of these also completed a follow‐up questionnaire about treatment of caries and existing restorations. Certain questions (six treatment scenarios) were repeated at follow‐up a mean (SD) of 36.0 (3.8) months later. A total of 224 were ‘full participants’ (enrolled in clinical studies and attended at least one network meeting); 181 were ‘partial participants’ (did not meet ‘full’ criteria).

Results

From 10% to 62% of practitioners were ‘surgically invasive’ at baseline, depending on the clinical scenario. Stated treatment approach was significantly less invasive at follow‐up for four of six items. Change was greater among full participants and those with a more‐invasive approach at baseline, with an overall pattern of movement away from the extremes.

Conclusions

These results are consistent with a preliminary conclusion that network participation fostered movement of scientific evidence into routine practice. PBRNs may foster movement of evidence into everyday practice as practitioners become engaged in the scientific process.
Early‐onset epileptic encephalopathy in a girl carrying a truncating mutation of the ARX gene: rethinking the ARX phenotype in females
Authors: Bettella E , Di Rosa G , Polli R , Leonardi E , Tortorella G , Sartori S , Murgia A
Published: October 2012

Severe early‐onset epilepsy is due to a number of known causes, although a clear etiology is not identifiable in up to a third of all the cases. Pathogenic sequence variations in the ARX gene have been described almost exclusively in males, whereas heterozygous female relatives, such as mothers, sisters and even grandmothers have been largely reported as asymptomatic or mildly affected. To investigate the pathogenic role of ARX in refractory epilepsy of early onset even in females, we have screened the ARX sequence in a population of 50 female subjects affected with unexplained epileptic encephalopathy with onset in the first year of life. We report the identification of a novel truncating mutation of the coding region of the ARX gene in a girl with a structurally normal brain. Our findings confirm the role of ARX in the pathogenesis of early epilepsy and underline the importance of screening of the ARX gene in both male and female subjects with otherwise unexplained early onset epileptic encephalopathy.
Polarizable elements in scabies infestation: a clue to diagnosis
Authors: Foo Chong Wee , Florell Scott R. , Bowen Anneli R.
Published: October 2012

The diagnosis of scabies infestation is straightforward in cases where mite parts are largely visible; however, mites are often not captured in a specimen's planes of section. Polariscopic examination is a fast and simple adjunctive diagnostic tool to light microscopy. We describe the unique polariscopic findings in scabies infestation. Two cases of crusted scabies and eight cases of typical scabies were subjected to polariscopic examination. Diagnostic mite parts were visualized in at least one section in all cases. Attached and detached spines as well as scybala (fecal material) are polarizable. Specifically, spines show a polarizable outer sheath with dark central core while scybala show peripherally concentrated, stippled birefringence. Similar stippled birefringence is visible within the gut of some mites whereas significant birefringence is not appreciated in other mite parts. These results suggest that polariscopic examination is a helpful clue in the diagnosis of scabies infestation, especially in cases where the body of the mite is not visualized.
Ammonites
Authors: Wright John K.
Published: October 2012

Ammonites were amongst the most successful marine animals during the Mesozoic. They evolved to fill a large variety of ecological niches across a wide spectrum of open‐ocean and marine shelf environments. Despite the fact that hundreds of thousands have been collected in the last 200 years and are available for study in museum collections, the biology of ammonites—how they lived—is very difficult to understand. They lived such exotic and strange lives comparable with no group alive today, and seemed to break all the rules of Darwinian biology. Their importance in stratigraphy is due to their rapid evolution, which gave rise to a more refined zonal scheme than is possible with any other group of fossil, making the need to understand ammonite biology of more than academic interest.
Significant bacterial contamination risk reduction with the use of diversion pouch
Authors: Lee C. K. , Wong H. K. , Ho P. L. , Tsoi W. C. , Lee K. Y. , Tsui G. T. F. , Chua E. , Leung J. N. S. , Lin C. K.
Published: October 2012

SUMMARY

Background

Significant efforts have been made towards bacterial risk minimization by limiting the chance of bacteria entering into collected blood, detecting its presence and eliminating them by pathogen reduction technology. Improved skin disinfection and the use of diversion pouch are effective upstream measures to reduce the risk of bacterial sepsis. Here we report on our experience with the use of blood bags with diversion pouch.

Materials and methods

An observational study was performed to compare the bacterial contamination rate for two periods of time, i.e. before and after introduction of diversion pouch into blood bags. The incidence of bacterial contamination was monitored by the existing bacterial surveillance programme using pooled samples from 5 units of random donor platelets underwent aerobic culture in the BacT/ALERT 3D system.

Results

Between 1 June 2004 and 31 May 2006 (blood bag without diversion pouch), 50 (0·0213%) out of 234 252 units of random donor platelets were found to have bacteria on culture whereas 15 (0·0057%) isolates out of 262 156 units were found from 1 June 2007 to 31 May 2009 (after diversion pouch was introduced). Overall, there was an 85% reduction in bacterial contaminated risk due to skin flora (P < 0·0001) but an increasing trend of detection of non skin flora such as Streptococcus bovis was noted.

Conclusion

Integration of diversion pouch into blood bags to divert the first 30 mL blood during blood collection on top of the current skin disinfection protocol can significantly reduce the risk of bacterial contamination.
Interventional cardiology audit report for 2011
Authors: Baker L.
Published: October 2012

In 2011 there were 658 percutaneous coronary intervention cases performed with more than 60% of the patients presenting to the hospital as an acute coronary syndrome. Most procedures consisted of balloon dilatation followed by stent deployment, and 93% of these stents were drug‐eluting stents. Procedural success was achieved in 93.3% of cases and an overall major adverse cardiac events rate of 3.6%. This includes a mortality rate of (0.5%).

In addition, there were 25 Core Valve procedures carried out. This is more than twice the amount of patients who had a transcatheter aortic valve implantation in 2010, reflecting the changing direction of the management of structural heart disease.
Multiple pairwise comparison procedures based on the Lin and Wang test for right censored survival data
Authors: Tressler Ameina , Chow Alan
Published: October 2012

When comparing the prognosis of more than two groups in clinical trials, researchers may use multiple comparison procedures to determine which treatments actually differ from one another. Methods of controlling the Family Wise Error (FWE) rate for multiple comparisons of survival curves have received attention in the statistical literature. Adjustments such as Bonferroni, Holm's, Steele's and the closed procedure based on the logrank test have been studied. If hazards cross, the adjustments based on the logrank test may not be the most appropriate. Chi (2005) developed multiple testing procedures based on weighted Kaplan–Meier statistics as these statistics may perform better than the logrank for non‐proportional hazards alternatives. The aim of this research is to propose multiple testing procedures based on the Lin and Wang (2004) statistic for all pairwise comparisons. Simulation studies have shown this statistic can be more powerful than the logrank for certain crossing hazards. Through simulation, the FWE rate and power of the Bonferroni and Holm's adjustments based on the Lin and Wang statistic will be studied. For comparison purposes, the same adjustment procedures based on the logrank and Wilcoxon will be included in the simulations. These methods are applied to data from the Bone marrow transplant registry.
Philosophical Diversity and Disagreement
Authors: Plant Bob
Published: October 2012

Widespread and lasting consensus has not been philosophy's fate. Indeed, one of philosophy's most striking features is its ability to accommodate “not only different answers to philosophical questions” but also “total disagreement on what questions arephilosophical” (Rorty, 58). It is therefore hardly surprising that philosophers' responses to this metaphilosophical predicament have been similarly varied. This article considers two recent diagnoses of philosophical diversity:Kornblith andRescher (respectively) claim that taking philosophical disagreement seriously does not lead to metaphilosophical scepticism. The article argues that their confidence is misplaced in so far as both wrongly assume that ordinary, first‐order philosophical practice and second‐order metaphilosophical reflection are separate enterprises.
Happiness, Eudaimonia, and The Principle of Descriptive Adequacy
Authors: Cashen Matthew
Published: October 2012

Historically, philosophers have identified happiness with, among other things, pleasure, contentment, desire satisfaction, and, if we count the Greek eudaimonia as happiness, the life of virtue. When faced with competing theories of happiness, we need a way to decide which theory is more accurate. According to Larry Wayne Sumner's principle of descriptive adequacy, the best theory of happiness is the theory that best describes our ordinary, pretheoretical beliefs and intuitions. The chief aim of this article is to show that the principle of descriptive adequacy is mistaken. To do this, it shows how the principle breaks down when applied to Aristotle's theory of eudaimonia, a theory Sumner claims to be descriptively inadequate as a theory of happiness. The article argues that we should reject descriptive adequacy as a metaphilosophical principle on the grounds that our intuitions and beliefs about happiness are too inchoate for any theory adequately to describe.
Molecular mechanism of fertilization in the pig
Authors: ITO Junya , KASHIWAZAKI Naomi
Published: October 2012

At fertilization, the sperm triggers resumption from the arrest, extrusion of the second polar body and pronuclear formation, the events of which are collectively acknowledged as ‘oocyte activation’. In all species up to date, oocyte activation requires a fertilization‐associated increase in the intracellular concentration of calcium. Especially in mammals, the signal of intracellular calcium rise at fertilization consists of periodical rises, which are also referred to as calcium oscillations. Our recent results suggest that these calcium oscillations have an important role in not only oocyte activation but also development of mammals. Pigs are animals of great agricultural value and ones in which assisted reproductive techniques, including somatic cell nuclear transfer, to produce gene‐modified pigs. Although reconstructed embryos require artificial activation stimuli which mimic fertilization‐associated increase of intracellular calcium in the oocytes, it has been known that the developmental ability of the oocytes after artificial activation is low and the regimen seems to be required for improvement. Recently we focused on two molecules, phospholipase C zeta and inositol 1,4,5‐triphosphate receptor which have important roles in regulation of calcium oscillations during fertilization in mammals, including pigs. In this review, we will discuss the present status and future perspective of molecular mechanisms during fertilization in pigs.
Bayesian tests of measurement invariance
Authors: Verhagen A. J. , Fox J. P.
Published: October 2012

Random item effects models provide a natural framework for the exploration of violations of measurement invariance without the need for anchor items. Within the random item effects modelling framework, Bayesian tests (Bayes factor, deviance information criterion) are proposed which enable multiple marginal invariance hypotheses to be tested simultaneously. The performance of the tests is evaluated with a simulation study which shows that the tests have high power and low Type I error rate. Data from the European Social Survey are used to test for measurement invariance of attitude towards immigrant items and to show that background information can be used to explain cross‐national variation in item functioning.
Thermal Conductivity of Graphene Nanoribbons: Effect of the Edges and Ribbon Width
Authors: Plachinda Paul , Evans David , Solanki Raj
Published: October 2012

We have calculated thermal conductance of graphene nanoribbons (GNRs) and their dependence on the type of ribbon edge termination (zigzag or armchair) and the width of the ribbon, which ranges from 50 Å to 50 μm. Our model incorporates the effect of edge roughness and includes edge roughness correlation functions for both types of termination. The dependence of thermal conductance on the width of the ribbons and relative contribution of different scattering mechanisms are also analyzed by means of the Green’s function approach to the edge scattering. High temperature thermal conductance of the nanoribbons was found to be 0.15 nW/K and 0.18 nW/K (corresponding to thermal conductivity, 4641 and 5266 W/mK, respectively, for 10 μm long GNRs) which is in a good agreement with the experimental results.
Characterization of Ectromelia Virus Deficient in
EVM036
, the Homolog of Vaccinia virus
F13L
, and Its Application for Rapid Generation of Recombinant Viruses
Authors: Roscoe Felicia , Xu Ren-Huan , Sigal Luis J.
Published: October 2012

The orthopoxvirus (OPV) vaccinia virus (VACV) requires an intact
F13L
gene to produce enveloped virions (EV) and to form plaques in cell monolayers. Simultaneous introduction of an exogenous gene and
F13L
into
F13L
-deficient VACV results in expression of the foreign gene and restoration of plaque size. This is used as a method to rapidly generate VACV recombinants without the need for drug selection. However, whether other OPVs require the orthologs of
F13L
to generate EV and form plaques, whether
F13L
orthologs and EV are important for OPV pathogenesis in natural hosts, and whether a system based on
F13L
ortholog deficiency can be used to generate recombinant OPVs other than VACV have not been reported. The
F13L
ortholog in ectromelia virus (ECTV), the agent of mousepox, is
EVM036
. We show that ECTV lacking
EVM036
formed small plaques and was highly attenuated
in vivo
but still induced strong antibody responses. Reintroduction of
EVM036
in tandem with the
DsRed
gene resulted in a virus that expressed DsRed in infected cells but was indistinguishable from wild-type ECTV in terms of plaque size and
in vivo
virulence. Thus, our data show that, like
F13L
in VACV,
EVM036
is required for ECTV plaque formation and that
EVM036
and EV are important for ECTV virulence. Our experiments also suggest that OPVs deficient in
F13L
orthologs could serve as safer anti-OPV vaccines. Further, our results demonstrate that ECTV deficient in
EVM036
can be exploited for the rapid generation of fully virulent ECTV expressing foreign genes of interest.
The Alphavirus E3 Glycoprotein Functions in a Clade-Specific Manner
Authors: Snyder Anthony J. , Mukhopadhyay Suchetana
Published: October 2012

The 80 trimeric, glycoprotein spikes that cover the surface of alphavirus particles are required for mediating viral entry into a host cell. Spike assembly is a regulated process that requires interactions between five structural proteins, E3, E2, 6K and its translational frameshift product TF, and E1. E3 is a small, ∼65-amino-acid glycoprotein that has two known functions: E3 serves as the signal sequence for translocation of the E3-E2-6K-E1 polyprotein into the endoplasmic reticulum (ER), and cleavage of E3 from E2 is essential for virus maturation. Nonetheless, when E3 is replaced with an ER signal sequence, spikes do not form and infectious particles are not assembled, suggesting an additional role(s) for E3 in the viral life cycle. To further investigate the role of E3 in spike assembly, we made chimeric viruses in which E3 from one alphavirus species is replaced with E3 from another species. Our results demonstrate that when E3 is interchanged between alphavirus species that belong to the same virus clade, viral titers and particle morphologies and compositions are similar to what are observed for the parental virus. In contrast, for chimeras in which E3 is derived from a different clade than the parental virus, we observed reduced titers and the formation of particles with atypical morphologies and protein compositions. We further characterized the E3 chimeras using a combination of structure-function and revertant analyses. This work revealed two specific interactions between E3 and its cognate E2 glycoprotein that are important for regulating spike assembly.
INFLATONLESS INFLATION
Authors: HO CHIU MAN , KEPHART THOMAS W.
Published: October 2012

We consider a (4+N)-dimensional Einstein gravity coupled to a nonlinear sigma model. This theory admits a solution in which the N extra dimensions contract exponentially while the ordinary space expand exponentially. Physically, the nonlinear sigma fields induce the dynamical compactification of the extra dimensions, which in turn drives inflation. No inflatons are required.
VARIANT POSE FACE RECOGNITION USING DISCRETE WAVELET TRANSFORM AND LINEAR REGRESSION
Authors: SHAHDI SEYED OMID , ABU-BAKAR SYED A. R.
Published: October 2012

Face recognition in constraint conditions is no longer a further challenge. However, even the best method is not able to cope with real world situations. In this paper, a robust method is proposed such that the performance of the face recognition system is still highly reliable even if the face undergoes large head rotation. Our proposed method considers local regions from half side of face rather than using the holistic face approach since in the former approach the "linearity" of features within the limited region is somewhat preserved regardless of the pose variation. Discrete wavelet transform is then utilized onto these patches in order to form face feature vectors. We train our recognizer using linear regression algorithm to interpret the relationship between a face vector for a specific pose and its corresponding frontal face feature vector. We demonstrate that our proposed method is able to recognize a non-frontal face with high accuracy even under low-resolution image by relying only on single frontal face in the database.
Memory Conductance Switching in a Ni–Ti–O Compound Thin Film
Authors: Inamdar Akbar I. , Kim Jongmin , Jang Byeonguk , Kim Duhwan , Im Hyunsik , Jung Woong , Kim Hyungsang
Published: October 2012

Nonvolatile conductance switching phenomena in a nickel-titanium oxide compound thin film were investigated for memory device applications. On/off switching ratios as high as ∼104 were observed. Whereas the low-resistance state (LRS) showed good retention and endurance properties, the high resistance state (HRS) showed unstable switching properties. The temperature dependence of the LRS and HRS revealed that the switching mechanism is fundamentally based on the repeated process of the electroforming and the rupture of conducting filaments. The authors suggest that relatively weaker chemical binding between the Ti and O causes the unstable electrical conduction in the HRS.
Investigation of Three-Dimensional Characteristics of Underwater Streamer Discharges
Authors: Ichiki Ryuta , Kanazawa Seiji , Tomokiyo Kosuke , Akamine Shuichi , Kocik Marek , Mizeraczyk Jerzy
Published: October 2012

We have developed a new three-dimensional (3D) observation method suitable for studying the structure of streamer discharges. Using this method we investigated the propagation of underwater streamer discharges generated in a nozzle-plate electrode system. As a result, the streamer branching angle was found to take a bell-shaped distribution having a mean value in the range of 65–75° with a standard deviation of about 20°. Moreover, we confirmed that the mean branching angle is a physical quantity that increases with water conductivity. The propagation velocity of the underwater streamer was estimated to be (2–3) ×104m/s.
Mechanisms that enforce bounds on packet lifetimes
Authors: Sloan Lansing
Published: October 2012

For reliable transport protocol operation the lifetime of packets should not exceed an assumed maximum packet lifetime (MPL). A packet's lifetime is spent in nodes and crossing links. Time spent in nodes and on simple links is easily found. Other links or logical links may lose, duplicate, delay, and reorder data and do not provide transittime information. We present a link-transit-time protocol for bounding the transit time of packets that cross such links.
Acknowledging DSMA with priority scheduling for local area networks
Authors: Mehta Maneesh , Mark Jon W.
Published: October 2012

A mini-slot, appended to the data slot in the distributed scheduling multiple access (DSMA) protocol described in [1], for the transmission of acknowledgement packets is described and analyzed. The resulting DSMA with fixed slot acknowledgement (DSMA/FSA) presents a better alternative to sending a separate acknowledgement packet for each received data packet. With priority requests, DSMA/FSA appears to be a viable media access protocol for integrated voice and data services in a local area network.
A gateway for linking local area networks and X.25 networks
Authors: Grant A. , Hutchison D. , Shepherd W. D.
Published: October 2012

This paper describes the hardware and software architecture of a gateway between an Ethernet-style local area network called Strathnet and an X.25 packet switched network (British Telecom's PSS). The hardware is based on a Motorola 68000 processor using the VME bus, and peripheral boards based on an 8-bit 68120/1 processor for the local network and the X.25 interfaces. The software is layered from the low-level executive, through the three X.25 levels and the transport layer, and through the corresponding layers on the local network side, to the bridging software itself. Both hardware and software are designed so that the system can be a general-purpose gateway: for example, the local area network peripheral board could be replaced by a ring type interface, and the software within the local network layers could similarly be replaced.
A bang-bang principle for real-time transport protocols
Authors: Yemini Yechiam
Published: October 2012

A real-time protocol is usually concerned with the transportation of a real-time data stream over a packet switched network. Among the major issues distinguishing real-time protocols from ordinary transport protocols is the problem of trading delay for loss. That is, if some loss of packets may be acceptable, and usually inevitable, the objective of the protocol is to minimize the delay of packets, subject to constraints on the acceptable loss. This is unlike usual transport protocols, which are designed to guarantee no loss at the expense of increased delays.

This paper presents a model for the delay-loss tradeoffs in a family of real-time transport protocols. It is demonstrated that, under very general assumptions, an optimal real-time protocol is a bang-bang protocol: there exists a threshold queue length such that as long as the packet queue length at the sender is less than the threshold the protocol should be an ordinary positive acknowledgement with retransmissions transport protocol. However, as soon as the threshold queue length is exceeded, a newly arriving packet causes the first (or any other) packet in the queue to be discarded. Closed form expressions for the threshold buffer size are obtained and analyzed in terms of the given parameters of the system.
Lookahead network priority protocols
Authors: Marcus S. I. , Lipovski G. J.
Published: October 2012

A new architecture for local area networks, based on the carry-lookahead circuit has been described in recent papers. It features a cost-effective hardware round-robin priority circuit, a bus and a shift register ring network that uses the same hardware. This paper shows that such an architecture can be used to minimize Σ Ui Wi where Ui is a real number urgency and Wi is the waiting time of message i, where Ui is a constant, or a time varying function which is a sequence of constant steps. Such a capability is useful in distributed real-time control systems. This paper demonstrates that a network that implements priority, bus and shift register ring-hardware can create new capabilities for local area networks.
A regulated NH2-terminal Sgk1 variant with enhanced function is expressed in the collecting duct
Authors: Raikwar Nandita S. , Liu Kang Z. , Thomas Christie P.
Published: October 2012

Sgk1 is a relatively unstable kinase that regulates epithelial Na+transport in the distal nephron of the kidney. We identified a 5′ variant alternate transcript of human Sgk1 (Sgk1_v3) that is expressed in the connecting tubule and collecting duct, is regulated by aldosterone and insulin, and is predicted to encode an NH2-terminal variant Sgk1 isoform, Sgk1_i3. Sgk1_i3 contains a polybasic motif, KKR, in its NH2terminus that regulates ubiquitination and stability of the expressed protein in HEK293 cells. In Fisher rat thyroid, and mpkCCDc14cells, Sgk1_i3 had a significantly greater effect on Na+transport compared with Sgk1 and its stimulatory effect was dependent on the kinase domain. Sgk1_i3 increased the abundance of cleaved epithelial Na+channel (ENaC) subunits at the cell surface, which was inhibited by coexpression of Nedd4–2. Together, the data demonstrate that a renally expressed Sgk1 isoform, Sgk1_i3, shows improved stability, is regulated by insulin and aldosterone, and stimulates ENaC activity when heterologously expressed in collecting duct cells.
Novel signaling mechanisms of intracellular angiotensin II-induced NHE3 expression and activation in mouse proximal tubule cells
Authors: Li X. C. , Hopfer U. , Zhuo J. L.
Published: October 2012

Expression of a cytosolic cyan fluorescent fusion protein of angiotensin II (ECFP/ANG II) in proximal tubules increases blood pressure in rodents. To determine cellular signaling pathways responsible for this response, we expressed ECFP/ANG II in transport-competent mouse proximal convoluted tubule cells (mPCT) from wild-type (WT) and type 1a ANG II receptor-deficient (AT1a-KO) mice and measured its effects on intracellular ANG II levels, surrogates of Na/H exchanger 3 (NHE3)-dependent Na+ absorption, as well as MAP kinases and NF-κB signaling. In WT mPCT cells, ECFP/ANG II expression doubled ANG II levels, increased NHE3 expression and membrane phospho-NHE3 proteins threefold and intracellular Na+ concentration by 65%. These responses were associated with threefold increases in phospho-ERK 1/2 and phospho-p38 MAPK, fivefold increases in p65 subunit of NF-κB, and threefold increases in phospho-IKKα/β (Ser 176/180) proteins. These signaling responses to ECFP/ANG II were inhibited by losartan (AT1 blocker), PD123319 (AT2 blocker), U0126 (MEK1/MEK2 inhibitor), and RO 106–9920 (NF-κB inhibitor). In mPCT cells of AT1a-KO mice, ECFP/ANG II also increased the levels of NHE3, p-ERK1/2, and p65 proteins above their controls, but considerably less so than in WT cells. In WT mice, selective expression of ECFP/ANG II in vivo in proximal tubules significantly increased blood pressure and indices of sodium reabsorption, in particular levels of phosphorylated NHE3 protein in the membrane fraction and proton gradient-stimulated 22Na+ uptake by proximal tubules. We conclude that intracellular ANG II may induce NHE3 expression and activation in mPCTs via AT1a- and AT2 receptor-mediated activation of MAP kinases ERK 1/2 and NF-κB signaling pathways.
Stochastic User Equilibrium Assignment in Schedule‐Based Transit Networks with Capacity Constraints
Authors: Xu Wangtu , Miao Lixin , Lin Wei-Hua
Published: October 2012

This paper proposes a stochastic user equilibrium (SUE) assignment model for a schedule‐based transit network with capacity constraint. We consider a situation in which passengers do not have the full knowledge about the condition of the network and select paths that minimize a generalized cost function encompassing five components: (1) ride time, which is composed of in‐vehicle and waiting times, (2) overload delay, (3) fare, (4) transfer constraints, and (5) departure time difference. We split passenger demands among connections which are the space‐time paths between OD pairs of the network. All transit vehicles have a fixed capacity and operate according to some preset timetables. When the capacity constraint of the transit line segment is reached, we show that the Lagrange multipliers of the mathematical programming problem are equivalent to the equilibrium passenger overload delay in the congested transit network. The proposed model can simultaneously predict how passengers choose their transit vehicles to minimize their travel costs and estimate the associated costs in a schedule‐based congested transit network. A numerical example is used to illustrate the performance of the proposed model.
Impact of Sun-Synchronous Diurnal Sampling on Tropical TOA Flux Interannual Variability and Trends
Authors: Taylor Patrick C. , Loeb Norman G.
Published: October 2012

Satellite observations of the earth’s radiation budget (ERB) are a critical component of the climate observing system. Recent observations have been made from sun-synchronous orbits, which provide excellent spatial coverage with global measurements twice daily but do not resolve the full diurnal cycle. Previous investigations show that significant errors can occur in time-averaged energy budgets from sun-synchronous orbits if diurnal variations are ignored. However, the impact of incomplete diurnal sampling on top-of-atmosphere (TOA) flux variability and trends has received less attention. A total of 68 months of 3-hourly tropical outgoing longwave radiation (OLR) and reflected shortwave radiation (RSW) fluxes from the Clouds and the Earth’s Radiant Energy System (CERES) synoptic (SYN) data product is used to examine the impact of incomplete diurnal sampling on TOA flux variability. Tropical OLR and RSW interannual variability and trends derived from sun-synchronous time sampling consistent with the Terra satellite from 2000 to 2005 show no statistically significant differences at the 95% confidence level with those obtained at 3-hourly time sampling at both 1° × 1° and 10° × 10° regional scales, as well as for tropical means. Monthly, 3-hourly OLR composite anomalies are decomposed into diurnally uniform and diurnal cycle shape change contributions to explain the impact of sampling on observed TOA flux variability. Diurnally uniform contributions to OLR variability account for more than 80% of interannual OLR variability at 1° × 1° spatial scales. Diurnal cycle shape variations are most important in equatorial land regions, contributing up to 50% to OLR variability over Africa. At spatial scales of 10° × 10° or larger, OLR variance contributions from diurnal cycle shape changes remain smaller than 20%.