bluuebunny/crossref_metadata_2025 huggingface dataset:
The antibacterial toxin colicin N binds to the inner core of lipopolysaccharide and close to its translocator protein
Authors: Johnson Christopher L. , Ridley Helen , Marchetti Roberta , Silipo Alba , Griffin David C. , Crawford Lucy , Bonev Boyan , Molinaro Antonio , Lakey Jeremy H.
Published: March 2014

Colicins are a diverse family of large antibacterial protein toxins, secreted by and active against Escherichia coli and must cross their target cell's outer membrane barrier to kill. To achieve this, most colicins require an abundant porin (e.g. OmpF) plus a low‐copy‐number, high‐affinity, outer membrane protein receptor (e.g. BtuB). Recently, genetic screens have suggested that colicin N (ColN), which has no high‐affinity receptor, targets highly abundant lipopolysaccharide (LPS) instead. Here we reveal the details of this interaction and demonstrate that the ColN receptor‐binding domain (ColN‐R) binds to a specific region of LPS close to the membrane surface. Data from in vitro studies using calorimetry and both liquid‐ and solid‐state NMR reveal the interactions behind the in vivo requirement for a defined oligosaccharide region of LPS. Delipidated LPS (LPSΔLIPID) shows weaker binding; and thus full affinity requires the lipid component. The site of LPS binding means that ColN will preferably bind at the interface and thus position itself close to the surface of its translocon component, OmpF. ColN is, currently, unique among colicins in requiring LPS and, combined with previous data, this implies that the ColN translocon is distinct from those of other known colicins.
Growing Pains: How Risk Perception and Risk Communication Research Can Help to Manage the Challenges of Global Population Growth
Authors: Dawson Ian G. J. , Johnson Johnnie E. V.
Published: March 2014

In 2011, the global human population reached 7 billion and medium variant projections indicate that it will exceed 9 billion before 2045. Theoretical and empirical perspectives suggest that this growth could lead to an increase in the likelihood of adverse events (e.g., food shortages, climate change, etc.) and/or the severity of adverse events (e.g., famines, natural disasters, etc.). Several scholars have posited that the size to which the global population grows and the extent to which this growth increases the likelihood of adverse outcomes will largely be shaped by individuals’ decisions (in households, organizations, governments, etc.). In light of the strong relationship between perceived risk and decision behaviors, it is surprising that there remains a dearth of empirical research that specifically examines the perceived risks of population growth and how these perceptions might influence related decisions. In an attempt to motivate this important strand of research, this article examines the major risks that may be exacerbated by global population growth and draws upon empirical work concerning the perception and communication of risk to identify potential directions for future research. The article also considers how individuals might perceive both the risks and benefits of population growth and be helped to better understand and address the related issues. The answers to these questions could help humanity better manage the emerging consequences of its continuing success in increasing infant survival and adult longevity.
Early and Middle Adolescents' Reasoning About Moral and Personal Concerns in Opposite‐sex Interactions
Authors: Shaw Leigh A. , Wainryb Cecilia , Smetana Judith
Published: March 2014

This study examined how adolescents coordinate personal and moral concerns in reasoning about opposite‐sex interactions. Sixty‐four early and middle adolescents (Ms = 12.74, 16.05 years) were individually interviewed about two hypothetical situations involving opposite‐sex interactions (commenting on appearance, initiating a date), presented in four conditions that varied the salience of personal vs. moral concerns. Overall, participants viewed opposite‐sex interactions as harmless and acceptable in personal conditions, but as moral concerns became more salient, they were viewed more negatively, as less contingent on the target's response, and as entailing humiliation, coercion, and victimization. Age differences occurred primarily in reasoning about conditions entailing mixed‐personal and moral concerns. Implications for adolescents' understanding of harassment and victimization are discussed.
Increase in cytosolic Ca2+ produced by hypoxia and other depolarizing stimuli activates a non‐selective cation channel in chemoreceptor cells of rat carotid body
Authors: Kang Dawon , Wang Jiaju , Hogan James O. , Vennekens Rudi , Freichel Marc , White Carl , Kim Donghee
Published: March 2014

Key points

Hypoxia is thought to depolarize glomus cells by inhibiting the outward K+ current, which sets in motion a cascade of ionic events that lead to transmitter secretion, increased afferent carotid sinus nerve activity and increased ventilation.

Our study of Na+‐permeable channels in glomus cells has revealed that hypoxia not only inhibits TASK background K+ channels but also indirectly activates a non‐selective cation channel with a single channel conductance of 20 pS. Under physiological conditions, the reversal potential of the cation channel is ∼ –28 mV, indicating that Na+ influx is also involved in hypoxia‐induced excitation of glomus cells.

Activation of the 20 pS cation channel is present when the O2 content is 5% or less, indicating that Na+ influx occurs during moderate to severe hypoxia (<5% O2), but not mild hypoxia (>5% O2).

The 20 pS cation channel is directly activated by a rise in intracellular Ca2+. Thus, factors that elevate intracellular Ca2+ such as hypoxia, extracellular acidosis and high external KCl all activate the cation channel. A feed‐forward mechanism may be present in which an initial depolarization‐induced rise in intracellular Ca2+ opens the Na+‐permeable cation channel, and the Na+ influx causes additional depolarization and influx of Ca2+ into glomus cells.

The current model of O2 sensing by carotid body chemoreceptor (glomus) cells is that hypoxia inhibits the outward K+ current and causes cell depolarization, Ca2+ influx via voltage‐dependent Ca2+ channels and a rise in intracellular [Ca2+] ([Ca2+]i). Here we show that hypoxia (<5% O2), in addition to inhibiting the two‐pore domain K+ channels TASK‐1/3 (TASK), indirectly activates an ∼20 pS channel in isolated glomus cells. The 20 pS channel was permeable to K+, Na+ and Cs+ but not to Cl− or Ca2+. The 20 pS channel was not sensitive to voltage. Inhibition of TASK by external acid, depolarization of glomus cells with high external KCl (20 mm) or opening of the Ca2+ channel with FPL64176 activated the 20 pS channel when 1 mm Ca2+ was present in the external solution. Ca2+ (10 μm) applied to the cytosolic side of inside‐out patches activated the 20 pS channel. The threshold [Ca2+]i for activation of the 20 pS channel in cell‐attached patches was ∼200 nm. The reversal potential of the 20 pS channel was estimated to be −28 mV. Our results reveal a sequential mechanism in which hypoxia (<5% O2) first inhibits the K+ conductance and then activates a Na+‐permeable, non‐selective cation channel via depolarization‐induced rise in [Ca2+]i. Our results suggest that inhibition of K+ efflux and stimulation of Na+ influx both contribute to the depolarization of glomus cells during moderate to severe hypoxia.
Neurotransmitters act as paracrine signals to regulate insulin secretion from the human pancreatic islet
Authors: Rodriguez‐Diaz Rayner , Menegaz Danusa , Caicedo Alejandro
Published: March 2014

In this symposium review we discuss the role of neurotransmitters as paracrine signals that regulate pancreatic islet function. A large number of neurotransmitters and their receptors has been identified in the islet, but relatively little is known about their involvement in islet biology. Interestingly, neurotransmitters initially thought to be present in autonomic axons innervating the islet are also present in endocrine cells of the human islet. These neurotransmitters can thus be released as paracrine signals to help control hormone release. Here we propose that the role of neurotransmitters may extend beyond controlling endocrine cell function to work as signals modulating vascular flow and immune responses within the islet.
Remote auditing of radiotherapy facilities using optically stimulated luminescence dosimeters
Authors: Lye Jessica , Dunn Leon , Kenny John , Lehmann Joerg , Kron Tomas , Oliver Chris , Butler Duncan , Alves Andrew , Johnston Peter , Franich Rick , Williams Ivan
Published: March 2014

Purpose:

On 1 July 2012, the Australian Clinical Dosimetry Service (ACDS) released its Optically Stimulated Luminescent Dosimeter (OSLD) Level I audit, replacing the previous TLD based audit. The aim of this work is to present the results from this new service and the complete uncertainty analysis on which the audit tolerances are based.

Methods:

The audit release was preceded by a rigorous evaluation of the InLight® nanoDot OSLD system from Landauer (Landauer, Inc., Glenwood, IL). Energy dependence, signal fading from multiple irradiations, batch variation, reader variation, and dose response factors were identified and quantified for each individual OSLD. The detectors are mailed to the facility in small PMMA blocks, based on the design of the existing Radiological Physics Centre audit. Modeling and measurement were used to determine a factor that could convert the dose measured in the PMMA block, to dose in water for the facilityˈs reference conditions. This factor is dependent on the beam spectrum. The TPR20,10 was used as the beam quality index to determine the specific block factor for a beam being audited. The audit tolerance was defined using a rigorous uncertainty calculation. The audit outcome is then determined using a scientifically based two tiered action level approach. Audit outcomes within two standard deviations were defined as Pass (Optimal Level), within three standard deviations as Pass (Action Level), and outside of three standard deviations the outcome is Fail (Out of Tolerance).

Results:

To‐date the ACDS has audited 108 photon beams with TLD and 162 photon beams with OSLD. The TLD audit results had an average deviation from ACDS of 0.0% and a standard deviation of 1.8%. The OSLD audit results had an average deviation of −0.2% and a standard deviation of 1.4%. The relative combined standard uncertainty was calculated to be 1.3% (1σ). Pass (Optimal Level) was reduced to ≤2.6% (2σ), and Fail (Out of Tolerance) was reduced to >3.9% (3σ) for the new OSLD audit. Previously with the TLD audit the Pass (Optimal Level) and Fail (Out of Tolerance) were set at ≤4.0% (2σ) and >6.0% (3σ).

Conclusions:

The calculated standard uncertainty of 1.3% at one standard deviation is consistent with the measured standard deviation of 1.4% from the audits and confirming the suitability of the uncertainty budget derived audit tolerances. The OSLD audit shows greater accuracy than the previous TLD audit, justifying the reduction in audit tolerances. In the TLD audit, all outcomes were Pass (Optimal Level) suggesting that the tolerances were too conservative. In the OSLD audit 94% of the audits have resulted in Pass (Optimal level) and 6% of the audits have resulted in Pass (Action Level). All Pass (Action level) results have been resolved with a repeat OSLD audit, or an on‐site ion chamber measurement.
Antibacterial Activity of Pepducins, Allosterical Modulators of Formyl Peptide Receptor Signaling
Authors: Winther Malene , Gabl Michael , Oprea Tudor I. , Jönsson Bodil , Boulay Francois , Bylund Johan , Dahlgren Claes , Forsman Huamei
Published: March 2014

Pepducins containing a fatty acid linked to an amino acid sequence derived from cytosolic parts of a G-protein-coupled receptor (GPCR) constitute a new group of lipopeptide tools in GPCR studies. Pepducins corresponding to the third intracellular loop of formyl peptide receptor 2 (FPR2) activate human neutrophils, and we show here that, in addition, these allosteric modulators of receptor activity also kill bacteria. The functional dualism of FPR2 pepducins could potentially be explored as a novel class of antibacterial drugs with immunomodulatory properties.
Visual restoration after suprachoroidal haemorrhage in glaucoma surgery
Authors: Rao Aparna
Published: March 2014

Suprachoroidal haemorrhage is the most dreaded complication feared by any surgeon during glaucoma surgery. Rapid explosive expulsion of intraocular contents can occur, which makes vision loss almost inevitable in most cases. Yet, adequate preparedness, prompt recognition of the earliest signs and quick closure of the wound can salvage the eye or even prevent loss of vision. This case highlights the successful visual rehabilitation and outcome in a patient with advanced glaucoma who experienced delayed expulsive haemorrhage intraoperatively.
A longitudinal general population-based study of job strain and risk for coronary heart disease and stroke in Swedish men
Authors: Torén Kjell , Schiöler Linus , Giang W K , Novak Masuma , Söderberg Mia , Rosengren Annika
Published: March 2014

Objectives

The aim was to investigate whether psychosocial stress based on the job-demand-control (JDC) model increased the risk for coronary heart disease (CHD) and stroke.

Setting

Swedish men.

Participants

The Primary Prevention Study (PPS) comprises 6070 men born between 1915 and 1925 free from previous history of CHD and stroke at baseline (1974–1977). Psychosocial workplace exposure was assessed using a job-exposure matrix (JEM) for the JDC model based on occupation at baseline. The participants were followed from baseline examination, until death, until hospital discharge or until 75 years of age, whichever occurred first, using the Swedish national register on cause of death and the Swedish hospital discharge register for non-fatal and fatal stroke and CHD events. Cox regression models were used with stroke or CHD as the outcome, using JDC model and age as explanatory variables, as well as stratified models with regard to smoking, self-reported stress, socioeconomic status, obesity, hypertension and diabetes.

Primary and secondary outcome measures

Risk for stroke and CHD.

Results

There was an increased risk (HR) for CHD in relation to high strain (HR 1.31, 95% CI 1.01 to 1.70). The risk was further increased among ever-smokers and among blue-collar workers. There was a relation between low control and increased risk for CHD (HR 1.19, 95% CI 1.06 to 1.35). There was no increased risk for stroke in any of the JDC categories.

Conclusions

Exposure to occupational psychosocial stress defined as job strain or low control increased the risk for CHD, especially among smokers and blue-collar workers. There was no increased risk for stroke in any of the JDC categories.
The promise of recovery: narratives of hope among homeless individuals with mental illness participating in a Housing First randomised controlled trial in Toronto, Canada
Authors: Kirst Maritt , Zerger Suzanne , Wise Harris Deborah , Plenert Erin , Stergiopoulos Vicky
Published: March 2014

Objectives

Hope is widely embraced as an important factor in the recovery process. The role of housing in inspiring hope and facilitating recovery has been explored with homeless populations but is not well understood. This study explores perspectives on hopes for recovery and the role of housing on these hopes from the perspective of homeless adults experiencing mental illness participating in a multisite Housing First randomised controlled trial in Canada. The study draws on data from in-depth qualitative interviews with participants from the Toronto, Ontario site of the ‘At Home/Chez Soi’ Project.

Design

In-depth interviews were conducted with a subsample of participants from a larger Housing First randomised controlled trial.

Setting

The research took place in Toronto, Canada.

Participants

60 participants in the larger trial (36 from the Housing First group and 24 from the Treatment as Usual group) took part in in-depth interviews.

Method

Participants for the in-depth interviews were purposively selected from the larger trial sample in Toronto and participated in an interview at the beginning of the study (baseline). Data from the baseline interviews were analysed using the constant comparative method derived from grounded theory methods.

Results

Participants’ narratives show clear visualisation of goals for recovery, and emphasise that housing is an integral factor that can facilitate hope and support dimensions of recovery. However, some participants had difficulty adjusting to housing, and were concerned about feeling socially isolated, which could have negative implications for hopefulness and recovery.

Conclusions

Housing First interventions should explicitly incorporate hope-inspiring, recovery-oriented approaches and support participants while adjusting to housing in order to sustain hopefulness.
Emergency intrauterine device insertion in teenagers: an informal retrospective study
Authors: Akintomide Hannat , Vinayagam Suganthi , Schünmann Catherine
Published: March 2014

Background

Widespread and increased availability of oral emergency contraception (EC) over the past 10 years has made little difference to rates of unintended pregnancy, abortion and repeat abortion amongst teenagers. The insertion of an intrauterine device for EC (EC-IUD) is 98–99% effective compared with 85% for oral methods and can be used for ongoing, long-term reversible contraception. However this method is seldom used for teenagers, a group with a high risk of unintended pregnancy, and there is little published data on the use of EC-IUD in this group.

Methods

An anonymous case note review of EC-IUD use in teenagers in three centres in the UK was conducted to quantify provision, to identify insertion difficulties and short-term complications and to ascertain compliance with national guidance concerning sexually transmitted infection (STI) risk assessment and prophylaxis.

Results

A total of 103 cases was identified over 4 years (2007–2010) from the three centres (London, Liverpool and Aberdeen). The results show that the majority of fittings were straightforward (94%) with few complications. Antibiotic prophylaxis was deemed necessary in 64% of attenders.

Conclusions

The authors recommend that with STI screening and appropriate antibiotic prophylaxis, use of IUDs in women under the age of 20 years should be unrestricted both for long-term contraception and for EC.
Approaches for estimating stand-level volume using terrestrial laser scanning in a single-scan mode
Authors: Astrup Rasmus , Ducey Mark J. , Granhus Aksel , Ritter Tim , von Lüpke Nikolas
Published: March 2014

The most efficient way to obtain stand inventory data with terrestrial laser systems (TLS) is with the single-scan mode, which involves taking one scan at a single point. With a single-scan setup, there will be a nondetection of trees in a plot and the representation of the individual trees will be incomplete. We explore how stand-level volume estimates, based on the single-scan mode, perform compared with standard inventory estimates. We base our study on 166 plots in 12 mature stands dominated by Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst) in southern Norway. First, we compare individual-tree volume estimates from TLS with estimates from volume functions and measurements from harvesters. We show that individual-tree volumes can be estimated with high precision and accuracy with TLS in single-scan mode. Secondly, we test three approaches for correction of nondetection relying on model-based estimates of the detection probability obtained by point transect sampling estimators. We show that all three approaches adjust for nondetection and yield stand-level volume estimates that are similar to those obtained by fixed-area sampling. In conclusion, our results indicate that stand-level volume estimates, based on single-scan mode TLS data, perform well compared with standard inventory estimates.
Aperiodicity and primitive ideals of row-finite k-graphs
Authors: Kang Sooran , Pask David
Published: March 2014

We describe the primitive ideal space of the C*-algebra of a row-finite k-graph with no sources when every ideal is gauge invariant. We characterize which spectral spaces can occur, and compute the primitive ideal space of two examples. In order to do this we prove some new results on aperiodicity. Our computations indicate that when every ideal is gauge invariant, the primitive ideal space only depends on the 1-skeleton of the k-graph in question.
Radial multipliers on amalgamated free products of II1-factors
Authors: Möller Sören
Published: March 2014

Let ℳi be a family of II1-factors, containing a common II1-subfactor 𝒩, such that [ℳi : 𝒩] ∈ ℕ0 for all i. Furthermore, let ϕ: ℕ0 → ℂ. We show that if a Hankel matrix related to ϕ is trace-class, then there exists a unique completely bounded map Mϕ on the amalgamated free product of the ℳi with amalgamation over 𝒩, which acts as a radial multiplier. Hereby, we extend a result of Haagerup and the author for radial multipliers on reduced free products of unital C*- and von Neumann algebras.
Inertia effects on strategy updating in emergency evacuation from a room with multiple exits
Authors: Zhao Yang , Li Yuanzhen
Published: March 2014

The inertia effects on strategy updating in emergency evacuation from a room with multiple exits is studied using the modified floor field model. Game theory is adopted to deal with conflict resolving process of evacuees and inertia effects are introduced in both exit choosing and conflict resolving process. From simulation results, the influences of inertia effects on the evacuation times and cooperation frequencies have been discussed. Interestingly, it can be found that inertia effects in exit choosing may lead more evacuation times, while inertia effects in conflict resolving may lead more evacuation times and higher cooperation frequencies. This study provides a new perspective to understand how the inertia of changing status quo acts on the strategy evolution in emergency circumstances.
Flavor violating bosonic squark decays at LHC
Authors: Bartl A. , Eberl H. , Ginina E. , Herrmann B. , Hidaka K. , Majerotto W. , Porod W.
Published: March 2014

We study quark flavor violation (QFV) in the squark sector of the Minimal Supersymmetric Standard Model (MSSM). We assume mixing between the second and the third squark generations, i.e. [Formula: see text] mixing. We focus on QFV effects in bosonic squark decays, in particular on the decay into the lightest Higgs boson [Formula: see text], where [Formula: see text] are the lightest up-type squarks. We show that the branching ratio of this QFV decay can be quite large (up to 50%) due to large QFV trilinear couplings, and large [Formula: see text] and [Formula: see text] mixing, despite the strong constraints on QFV from B meson data. This can result in characteristic QFV final states with significant rates at LHC (14 TeV), such as [Formula: see text] and [Formula: see text]. The QFV bosonic squark decays can have an influence on the squark and gluino searches at LHC.
One-dimensional periodic Anderson model
Authors: Gulacsi M.
Published: March 2014

In this paper, we study the one-dimensional periodic Anderson model via bosonization. In the Toulouse limit, an effective Hamiltonian for the correlated electrons is derived. The effective Hamiltonian provides new information in understanding the emergence of ferromagnetism in the model.
Symmetric criticality for tight knots
Authors: Cantarella Jason , Fu Joseph H. G. , Mastin Matt , Royal Jennifer Ellis
Published: March 2014

We prove a version of symmetric criticality for ropelength-critical knots. Our theorem implies that a knot or link with a symmetric representative has a ropelength-critical configuration with the same symmetry. We use this to construct new examples of ropelength-critical configurations for knots and links which are different from the ropelength minima for these knot and link types.
An investigation of p+8He elastic scattering
Authors: Mahmoud Zakaria M. M. , Ibraheem Awad A. , Farid M. El-Azab
Published: March 2014

The vector analyzing power and differential cross-section for the elastic scattering of 8 He nucleus from polarized protons at 71 MeV/nucleon have been analyzed in the framework of the optical model potentials. Microscopic single folding (SF) optical potentials (OP) have been constructed based upon two different effective nucleon–nucleon (NN) interactions, namely Jeukenne–Lejeune–Mahaux (JLM) and BDM3Y1 effective interactions. The effect of 8 He nuclear structure has been tested through two different choices of the nuclear density distribution. It is concluded that the nucleus 8 He may be considered as a thick skin exotic nucleus. In order to investigate the vector analyzing power data, besides the Thomas phenomenological representation, three different forms of the spin–orbit (SO) part of the OP have been considered. These forms are based directly or indirectly upon the density distribution of 8 He nucleus. It is found that SO potentials of larger root mean square radii are able to successfully describe the vector analyzing power data more than those of shorter radii.
Homogeneous Calderón–Zygmund estimates for a class of second-order elliptic operators
Authors: Galdi G. P. , Metafune G. , Spina C. , Tacelli C.
Published: March 2014

We prove unique solvability and corresponding homogeneous Lp estimates for the Poisson problem associated to the uniformly elliptic operator [Formula: see text], provided the coefficients are bounded and uniformly continuous, and admit a (non-zero) limit as |x| goes to infinity. Some important consequences are also derived.
On non-abelian Schur groups
Authors: Ponomarenko Ilya , Vasil'ev Andrey
Published: March 2014

A finite group G is called Schur, if every Schur ring over G is associated in a natural way with a regular subgroup of sym (G) that is isomorphic to G. We prove that any non-abelian Schur group G is metabelian and the number of distinct prime divisors of the order of G does not exceed 7.
Global L2error of wavelet density estimator with truncated and strong mixing observations
Authors: Zou Yu-Ye , Liang Han-Ying
Published: March 2014

In this paper, we discuss the global L2-error of the nonlinear wavelet estimator of density in the Besov space [Formula: see text] for the truncation model when the data exhibit strong mixing assumption, and prove that the estimator can achieve the optimal rate of convergence, which is similar to that in the complete and independent data case with term-by-term thresholding of the empirical wavelet coefficients (D. L. Donoho, I. M. Johnstone, G. Kerkyacharian and D. Picard, Density estimation by wavelet thresholding, Ann. Statist.24 (1996) 508–539). In addition, the conclusion shows that the convergence rate of the nonlinear estimator is faster than that of its linear estimator in some range.
Particle Sedimentation in a Constricted Passage Using a Flexible Forcing IB-LBM Scheme
Authors: Dash S. M. , Lee T. S. , Huang H.
Published: March 2014

A novel flexible forcing hybrid immersed boundary-lattice Boltzmann model (IB-LBM) is introduced in the present paper for solving moving boundary problems. In conventional IB-LBM schemes, explicit formulations of force density term may not ensure no-slip boundary condition accurately, which leads to inaccurate force and torque calculations for moving object. Following an implicit force density calculation, a single Lagrangian velocity correction term is advised in this study. The formula for this correction term is much simpler and with the help of flexible number of sub-iteration/forcing, the computational time is significantly saved. The no-slip boundary condition is achieved accurately within a convergence limit. The proposed algorithm shows advantages for unsteady and moving boundary problem, where boundary convergence is satisfied consistently at every time step. In particular, a 2D particulate flow case is simulated in a constricted channel. Interesting observations and results are discussed in this article.
Investigation of human visual cortex responses to flickering light using functional near infrared spectroscopy and constrained ICA
Authors: Thang Nguyen Duc , Toi Vo Van , Tran Le Giang , Tam Nguyen Huynh Minh , Trinh Lan Anh
Published: March 2014

The human visual sensitivity to the flickering light has been under investigation for decades. The finding of research in this area can contribute to the understanding of human visual system mechanism and visual disorders, and establishing diagnosis and treatment of diseases. The aim of this study is to investigate the effects of the flickering light to the visual cortex by monitoring the hemodynamic responses of the brain with the functional near infrared spectroscopy (fNIRS) method. Since the acquired fNIRS signals are affected by physiological factors and measurement artifacts, constrained independent component analysis (cICA) was applied to extract the actual fNIRS responses from the obtained data. The experimental results revealed significant changes (p < 0.0001) of the hemodynamic responses of the visual cortex from the baseline when the flickering stimulation was activated. With the uses of cICA, the contrast to noise ratio (CNR), reflecting the contrast of hemodynamic concentration between rest and task, became larger. This indicated the improvement of the fNIRS signals when the noise was eliminated. In subsequent studies, statistical analysis was used to infer the correlation between the fNIRS signals and the visual stimulus. We found that there was a slight decrease of the oxygenated hemoglobin concentration (about 5.69%) over four frequencies when the modulation increased. However, the variations of oxy and deoxy-hemoglobin were not statistically significant.
Enhanced thermoelectric properties ofN-type polycrystallineIn4Se3-xcompounds via thermally inducedSedeficiency
Authors: Zhao Ran , Shu Yu-Tian , Guo Fu
Published: March 2014

In4Se3-xcompound is considered as a potential thermoelectric material due to its comparably low thermal conductivity among all existing ones. While most studies investigated In4Se3-xthermoelectric properties by controlling selennium or other dopants concentrations, in the current study, it was found that even for a fixed initial In / Se ratio, the resulting In / Se ratio varied significantly with different thermal processing histories (i.e., melting and annealing), which also resulted in varied thermoelectric properties as well as fracture surface morphologies of In4Se3-xpolycrystalline specimens. Single phase polycrystalline In4Se3-xcompounds were synthesized by combining a sequence of melting, annealing, pulverizing, and spark plasma sintering. The extension of previous thermal history was observed to significantly improve the electrical conductivity (about 121%) and figure of merit (about 53%) of In4Se3-xpolycrystalline compounds. The extended thermal history resulted in the increase of Se deficiency (x) from 0.39 to 0.53. This thermally induced Se deficiency was observed to associate with increasing carrier mobility but decreasing concentration, which differs from the general trend observed for the initially adjusted Se deficiency at room temperature. Unusually large dispersed grains with nanosize layers were observed in specimens with the longest thermal history. The mechanism(s) by which previous thermal processing enhances carrier mobility and affect microstructural evolution are briefly discussed.
INHOMOGENEOUS ELECTRON GAS AT OXIDE INTERFACES WITH STRONG RASHBA SPIN–ORBIT COUPLING
Authors: CAPRARA S. , BUCHELI D. , GRILLI M. , BISCARAS J. , BERGEAL N. , HURAND S. , FEUILLET-PALMA C. , LESUEUR J. , RASTOGI A. , BUDHANI R. C.
Published: March 2014

The 2D electron gas (2DEG) formed at the LaXO 3/ SrTiO 3( X = Al , Ti ) oxide interface appears inhomogeneous in several experiments. In particular, we discuss evidences of electron inhomogeneities provided by the phenomenology of the superconducting (SC) phase, which occurs when the carrier density is tuned above a critical value by means of gating, and of the superconductor-to-metal transition driven by gate voltage or magnetic field. The measured resistance and superfluid density result from the percolative connection of superconducting "puddles" with randomly distributed critical temperatures, embedded in a weakly localizing metallic matrix. We propose a possible intrinsic origin of the electron inhomogeneity, resulting from the strong Rashba spin–orbit coupling (RSOC) measured at these oxide interfaces.
Why China is Fixated on the Moon
Authors: Shukman David
Published: March 2014

The Moon could be a "beautiful" source of minerals and energy, a top Chinese scientist has told the BBC. Exotic materials including helium-3 and the potential for solar power could prove invaluable for humankind, he says. The comments come from Prof Ouyang Ziyuan of the department of lunar and deep space exploration. His first interview with the foreign media provides insights into China's usually secretive space programme.
Quantifier-free interpolation in combinations of equality interpolating theories
Authors: Bruttomesso Roberto , Ghilardi Silvio , Ranise Silvio
Published: March 2014

The use of interpolants in verification is gaining more and more importance. Since theories used in applications are usually obtained as (disjoint) combinations of simpler theories, it is important to modularly reuse interpolation algorithms for the component theories. We show that a sufficient and necessary condition to do this for quantifier-free interpolation is that the component theories have the
strong
(
sub
-)
amalgamation
property. Then, we provide an equivalent syntactic characterization and show that such characterization covers most theories commonly employed in verification. Finally, we design a combined quantifier-free interpolation algorithm capable of handling both convex and nonconvex theories; this algorithm subsumes and extends most existing work on combined interpolation.
Cross-Lingual Annotation Projection for Weakly-Supervised Relation Extraction
Authors: Kim Seokhwan , Jeong Minwoo , Lee Jonghoon , Lee Gary Geunbae
Published: March 2014

Although researchers have conducted extensive studies on relation extraction in the last decade, statistical systems based on supervised learning are still limited, because they require large amounts of training data to achieve high performance level. In this article, we propose cross-lingual annotation projection methods that leverage parallel corpora to build a relation extraction system for a resource-poor language without significant annotation efforts. To make our method more reliable, we introduce two types of projection approaches with noise reduction strategies. We demonstrate the merit of our method using a Korean relation extraction system trained on projected examples from an English-Korean parallel corpus. Experiments show the feasibility of our approaches through comparison to other systems based on monolingual resources.
Distortion Model Based on Word Sequence Labeling for Statistical Machine Translation
Authors: Goto Isao , Utiyama Masao , Sumita Eiichiro , Tamura Akihiro , Kurohashi Sadao
Published: March 2014

This article proposes a new distortion model for phrase-based statistical machine translation. In decoding, a distortion model estimates the source word position to be translated next (subsequent position; SP) given the last translated source word position (current position; CP). We propose a distortion model that can simultaneously consider the word at the CP, the word at an SP candidate, the context of the CP and an SP candidate, relative word order among the SP candidates, and the words between the CP and an SP candidate. These considered elements are called
rich context
. Our model considers rich context by discriminating label sequences that specify spans from the CP to each SP candidate. It enables our model to learn the effect of relative word order among SP candidates as well as to learn the effect of distances from the training data. In contrast to the learning strategy of existing methods, our learning strategy is that the model learns preference relations among SP candidates in each sentence of the training data. This leaning strategy enables consideration of all of the rich context simultaneously. In our experiments, our model had higher BLUE and RIBES scores for Japanese-English, Chinese-English, and German-English translation compared to the lexical reordering models.
Multidimensional stochastic approximation
Authors: Broadie Mark , Cicek Deniz M. , Zeevi Assaf
Published: March 2014

We consider prototypical sequential stochastic optimization methods of Robbins-Monro (RM), Kiefer-Wolfowitz (KW), and Simultaneous Perturbations Stochastic Approximation (SPSA) varieties and propose adaptive modifications for multidimensional applications. These adaptive versions dynamically scale and shift the tuning sequences to better match the characteristics of the unknown underlying function, as well as the noise level. We test our algorithms on a variety of representative applications in inventory management, health care, revenue management, supply chain management, financial engineering, and queueing theory.
Degree lower bounds of tower-type for approximating formulas with parity quantifiers
Authors: Atserias Albert , Dawar Anuj
Published: March 2014

Kolaitis and Kopparty have shown that for any first-order formula with parity quantifiers over the language of graphs, there is a family of multivariate polynomials of constant-degree that agree with the formula on all but a 2

−Ω(
n
)

-fraction of the graphs with
n
vertices. The proof bounds the degree of the polynomials by a tower of exponentials whose height is the nesting depth of parity quantifiers in the formula. We show that this tower-type dependence is necessary. We build a family of formulas of depth
q
whose approximating polynomials must have degree bounded from below by a tower of exponentials of height proportional to
q
. Our proof has two main parts. First, we adapt and extend the results by Kolaitis and Kopparty that describe the joint distribution of the parities of the numbers of copies of small subgraphs in a random graph to the setting of graphs of growing size. Second, we analyze a variant of Karp's graph canonical labeling algorithm and exploit its massive parallelism to get a formula of low depth that defines an almost canonical pre-order on a random graph.
A PSPACE-complete first-order fragment of computability logic
Authors: Bauer Matthew S.
Published: March 2014

In a recently launched research program for developing logic as a formal theory of (interactive) computability, several very interesting logics have been introduced and axiomatized. These fragments of the larger Computability Logic aim not only to describe what can be computed, but also provide a mechanism for extracting computational algorithms from proofs. Among the most expressive and fundamental of these is CL4, known to be (constructively) sound and complete with respect to the underlying computational semantics. Furthermore, the ∀, ∃-free fragment of CL4 was shown to be decidable in polynomial space. The present work extends this result and proves that this fragment is, in fact, PSPACE-complete.
Cell
Authors: Kim Eunjin , Achituv Romy
Published: March 2014

Users breathe life into a pneumatically controlled installation and performance wearable.
Nanopipelined threshold network synthesis
Authors: Pierce Luke , Tragoudas Spyros
Published: March 2014

Threshold logic gates allow for complex multiinput functions to be implemented using a single gate thereby reducing the power and area of a circuit. Clocked threshold gates are nanopipelined to increase network throughput. It is shown that synthesis methods that do not consider the synchronization of the nanopipeline can produce an enormous amount of buffers. The proposed algorithm synthesizes a Boolean network into a nanopipelined threshold logic network by minimizing not only the number of combinational clusters but also the associated buffer insertion overhead.
Inexact computing using probabilistic circuits
Authors: Kim Jaeyoon , Tiwari Sandip
Published: March 2014

Numerous computing applications can tolerate low error rates. In such applications, inexact approaches provide the ability to achieve significantly lower power. This work demonstrates the power-error trade-offs that can be achieved. Using probabilistic modeling in sub-50-nm silicon transistor technology, the relationship between statistical uncertainties and errors are elucidated for different configurations and topologies and the trade-offs quantified. Gate-level implementation of the probabilistic CMOS logic is validated by circuit simulations of a commercial 45-nm SOI CMOS process technology. Using a practical ALU architecture where voltages can be scaled from most significant to least significant bit blocks as an example, the potential benefits of this technique are shown. A calculation error of 10
−6
, an error rate quite tolerable for many computational tasks, is shown to be possible with a total power reduction of more than 40%.
Critical-reliability path identification and delay analysis
Authors: Chen Jifeng , Wang Shuo , Tehranipoor Mohammad
Published: March 2014

Circuit reliability analysis at the presilicon stage has become vital for sub-45nm technology designs in particular, due to aging effects, such as Negative Bias Temperature Instability (NBTI) and Hot Carrier Injection (HCI). To avoid potential reliability hazards in the postsilicon stage, current large-scale designs for commercial implementation overpessimistically analyze circuit aging under assumed worst-case workload in order not to violate the corner cases even for low possibilities, thus introducing unnecessary margin in the design timing analysis. The major issue is lack of an effective aging analysis method applicable to large designs with low CPU runtime, which is mainly due to: (1) conventional reliability tools are extremely time-consuming for circuit-level timing analysis and thus are not practical for large designs; (2) mathematical models developed to expedite the process are not accurate due to the high complexity of aging effects. In this article, a comprehensive analysis is presented to highlight the importance of each aging parameter. Then, a novel methodology is developed based on current commercial reliability tools to guarantee its high accuracy on circuit-level aging analysis. Existing proven low-level mathematical models are further enhanced to extensively speed up a higher level analysis by taking advantage of the explicit intermediate conditions stored in a pregenerated lookup table. Our results indicate ≥244
X
improved computational efficiency, ≤5% relative error, and ≤0.7% absolute error compared with commercial reliability analysis tools (e.g., HSPICE MOSRA).
On-chip sensor networks for soft-error tolerant real-time multiprocessor systems-on-chip
Authors: Liu Weichen , Wang Xuan , Xu Jiang , Zhang Wei , Ye Yaoyao , Wu Xiaowen , Nikdast Mahdi , Wang Zhehui
Published: March 2014

As transistor density continues to increase with the advent of nanotechnology, reliability issues raised by the more frequent appearance of soft errors are becoming critical for future embedded multiprocessor systems design. State-of-the-art techniques for soft error protections targeting multiprocessor systems result either high chip cost and area overhead or high performance degradation and energy consumption, and do not fulfill the increasing requirements for high performance and dependability. In this article we present a systematic approach, that is, the Sensor Networks-on-Chip (SENoC), to collaboratively and efficiently manage on-chip applications and overcome reliability threats to Multiprocessor Systems-on-Chip (MPSoC). A hardware-software collaborative approach is proposed to solve soft error problems: a hardware-based on-chip sensor network is built for soft error detection, and a software-based recovery mechanism is applied for soft error correction. A two-step scheduling scheme is presented for reliable application and chip management, combining an off-line static optimization stage for application performance maximization and an online lightweight dynamic adjustment stage to handle runtime variations and exceptions. This strategy introduces only trivial overhead on hardware design and much lower overhead on software control and execution, and hence performance degradation and energy consumption is greatly reduced. We build a cycle-accurate simulator using SystemC, and verify the effectiveness of our technique by comparing performance with related techniques on several real-world applications.
Demo hour
Authors: Kim Sangtae , Kim Jaejeung , Lee Soobin , Petkov Ivan , Ronchi Gloria , Benghi Claudio , Bengler Ben , Bryan-Kinns Nick
Published: March 2014

Demo Hour highlights new prototypes and projects that exemplify innovation and novel forms of interaction. Audrey Desjardins, Editor
Understanding the social web
Authors: Appleford Simon , Bottum James R. , Thatcher Jason Bennett
Published: March 2014

This paper identifies issues that must be considered by Information Systems scholars interested in helping to build a rich, interdisciplinary community to support applied research into the impact of the social web. We describe challenges and opportunities presented by the social web for Information Systems research and argue that an interdisciplinary approach may address the challenges of pursuing research questions about ephemeral social web phenomena. Through the creation of communities of practice that bring together faculty, IT professionals, and students from across academic colleges and high performance computing groups that lay a foundation for collaboration, information systems scholars may realize new opportunities for behavioral, design science, business intelligence, and IS strategy research. More importantly, through an interdisciplinary community of practice, we may inform how to develop an information systems curriculum that equips our students to participate in the growing knowledge economy.
Reduced resting skeletal muscle protein synthesis is rescued by resistance exercise and protein ingestion following short-term energy deficit
Authors: Areta José L. , Burke Louise M. , Camera Donny M. , West Daniel W. D. , Crawshay Siobhan , Moore Daniel R. , Stellingwerff Trent , Phillips Stuart M. , Hawley John A. , Coffey Vernon G.
Published: March 2014

The myofibrillar protein synthesis (MPS) response to resistance exercise (REX) and protein ingestion during energy deficit (ED) is unknown. In young men ( n = 8) and women ( n = 7), we determined protein signaling and resting postabsorptive MPS during energy balance [EB; 45 kcal·kg fat-free mass (FFM)−1·day−1] and after 5 days of ED (30 kcal·kg FFM−1·day−1) as well as MPS while in ED after acute REX in the fasted state and with the ingestion of whey protein (15 and 30 g). Postabsorptive rates of MPS were 27% lower in ED than EB ( P < 0.001), but REX stimulated MPS to rates equal to EB. Ingestion of 15 and 30 g of protein after REX in ED increased MPS ∼16 and ∼34% above resting EB ( P < 0.02). p70 S6K Thr389 phosphorylation increased above EB only with combined exercise and protein intake (∼2–7 fold, P < 0.05). In conclusion, short-term ED reduces postabsorptive MPS; however, a bout of REX in ED restores MPS to values observed at rest in EB. The ingestion of protein after REX further increases MPS above resting EB in a dose-dependent manner. We conclude that combining REX with increased protein availability after exercise enhances rates of skeletal muscle protein synthesis during short-term ED and could in the long term preserve muscle mass.