bluuebunny/crossref_metadata_2025 huggingface dataset:
Systematic evaluation of evidence on veterinary viscoelastic testing Part 3: Assay activation and test protocol
Authors: de Laforcade Armelle , Goggs Robert , Wiinberg Bo
Published: January 2014

Objective

To systematically examine the evidence on activating agents and test protocols for the thrombelastography (TEG) and rotational thrombelastometry (ROTEM) viscoelastic point‐of‐care instruments and to identify knowledge gaps.

Design

Ten questions were considered, the primary question addressed the use of activating agents and secondary questions addressed assay temperature, length of analysis, pipetting, sample volume, reproducibility, and quality controls. Standardized, systematic evaluation of the literature was performed. Relevant articles were categorized according to level of evidence (LOE). Consensus was developed regarding conclusions for application of concepts to clinical practice.

Setting

Academic and referral veterinary medical centers.

Results

PubMed and CAB abstracts were searched. Twenty papers were initially identified concerning the primary question; 16 were in support of the questions (LOE 2 Good, LOE 3 Good, LOE 5 Good, LOE 6 Good, LOE 5 Fair, LOE 6 Fair); and 4 were neutral (LOE 3 Good, LOE 6 Good, LOE Fair, LOE 5 Fair). Additional papers were evaluated post hoc during manuscript preparation.

Conclusions

Overall, there is a body of evidence from veterinary and human medicine that strongly suggests that TEG or ROTEM assays using citrated samples that employ an activator have significantly lower inherent variability than those that use recalcification alone. There is also strong evidence in dogs, cats, and humans that the results obtained using different activators are not directly comparable. There is no evidence to suggest that any one activating agent is superior to another for all patient populations, or drug monitoring indications. As such, use of more than one assay for complete thromboelastographic evaluation of a patient's coagulation system may be warranted. Standardization of the concentrations of activators would be beneficial.
Acceleration of ultrasound thermal therapy by patterned acoustic droplet vaporization
Authors: Kripfgans Oliver D. , Zhang Man , Fabiilli Mario L. , Carson Paul L. , Padilla Frederic , Swanson Scott D. , Mougenot Charles , Brian Fowlkes J. , Mougenot Charles
Published: January 2014

One application of acoustic droplet vaporization (ADV), a method of converting biocompatible microdroplets into microbubbles, is to enhance locally high intensity focused ultrasound (HIFU) therapy. Two objectives are pursued here: (1) the controlled creation of a bubble trench prior to HIFU using ADV and (2) use of the trench for increasing ablation volumes, lowering acoustic powers, and decreasing therapy duration. Thermally responsive phantoms were made with perfluorocarbon emulsion. Compound lesions were formed in a laboratory setting and a clinical magnetic resonance imaging (MRI)-guided HIFU system. Linear and spiral patterned compound lesions were generated in trenches. A larger fraction of the HIFU beam is contained to increase the generation of heat. Using the laboratory system, a 90 mm linear length spiral trench was formed in 30 s with mechanical beam steering. Comparatively, the clinical HIFU system formed a 19.9 mm linear length spiral trench in approximately 1 s with electronic beam steering. Lesions were imaged optically and with MRI. A uniform thermal ablation volume of 3.25 mL was achieved in 55.4 s (4-times faster than standard clinical HIFU and 14-times larger volume versus sum of individual lesions). Single lesions showed a 400% volume increase.
Variational formulation of the Stevens-Tiersten equation and application in the analysis of rectangular trapped-energy quartz resonators
Authors: Shi Junjie , Fan Cuiying , Zhao Minghao , Yang Jiashi
Published: January 2014

The two-dimensional scalar differential equation for transversely varying thickness modes in quartz crystal resonators operating with thickness-shear modes is formulated into variational form for trapped-energy resonators with both electroded and unelectroded regions. A theoretical analysis of rectangular trapped-energy resonators of singly rotated quartz is performed using the Ritz method based on the variational formulation. Free vibration resonant frequencies and modes are obtained. The results show the existence of trapped modes under the electrodes. The effects of various geometric and physical parameters on the trapped modes are examined. It is also found that the classical frequency prediction given by Tiersten and Smythe from an approximate analysis using the scalar differential equation has an inaccuracy on the order of 100 ppm for the fundamental mode, significant in resonator design.
A statistical-based approach for acoustic tomography of the atmosphere
Authors: Kolouri Soheil , Azimi-Sadjadi Mahmood R. , Ziemann Astrid
Published: January 2014

Acoustic travel-time tomography of the atmosphere is a nonlinear inverse problem which attempts to reconstruct temperature and wind velocity fields in the atmospheric surface layer using the dependence of sound speed on temperature and wind velocity fields along the propagation path. This paper presents a statistical-based acoustic travel-time tomography algorithm based on dual state-parameter unscented Kalman filter (UKF) which is capable of reconstructing and tracking, in time, temperature, and wind velocity fields (state variables) as well as the dynamic model parameters within a specified investigation area. An adaptive 3-D spatial-temporal autoregressive model is used to capture the state evolution in the UKF. The observations used in the dual state-parameter UKF process consist of the acoustic time of arrivals measured for every pair of transmitter/receiver nodes deployed in the investigation area. The proposed method is then applied to the data set collected at the Meteorological Observatory Lindenberg, Germany, as part of the STINHO experiment, and the reconstruction results are presented.
Vocal tract resonances in singing: Variation with laryngeal mechanism for male operatic singers in chest and falsetto registers
Authors: Henrich Bernardoni Nathalie , Smith John , Wolfe Joe
Published: January 2014

Seven male operatic singers sang the same notes and vowels in their chest and their falsetto registers, covering the overlap frequency range where two main laryngeal mechanisms can be identified by means of electroglottography: M1 in chest register and M2 in falsetto register. Glottal contact quotients determined using electroglottography were typically lower by 0.27 in M2 than in M1. Vocal tract resonance frequencies were measured by using broadband excitation at the lips and found to be typically lower in M2 than in M1 sung at the same pitch and vowel; R1 typically by 65 Hz and R2 by 90 Hz. These shifts in tract resonances were only weakly correlated with the changes in the contact quotient or laryngeal height that were measured simultaneously. There was considerable variability in the resonance tuning strategies used by the singers, and no evidence of a uniform systematic tuning strategy used by all singers. A simple model estimates that the shifts in resonance frequencies are consistent with the effective glottal area in falsetto register (M2) being 60%–70% of its value in chest register (M1).
Presence and seasonal variation of deep diving foraging odontocetes around Kauai, Hawaii using remote autonomous acoustic recorders
Authors: Au Whitlow W. L. , Giorli Giacomo , Chen Jessica , Copeland Adrienne , Lammers Marc O. , Richlen Michael , Jarvis Susan , Morrissey Ronald , Moretti David
Published: January 2014

Ecological acoustic recorders (EARs) were moored off the bottom in relatively deep depths (609–710 m) at five locations around the island of Kauai. Initially, the EARs had an analog-to-digital sample rate of 64 kHz with 30-s recordings every 5 min. After the second deployment the sampling rate was increased to 80 kHz in order to better record beaked whale biosonar signals. The results of the 80 kHz recording are discussed in this manuscript and are the results of three deployments over a year's period (January 2010 to January 2011). Five categories of the biosonar signal detection of deep diving odontocetes were created, short-finned pilot whales, sperm whales, beaked whales, Risso's dolphins, and unknown dolphins. During any given day, at least one species of these deep diving odontocetes were detected. On many days, several species were detected. The biosonar signals of short-finned pilot whales were detected the most often with approximately 30% of all the signals, followed by beaked and sperm whales approximately 22% and 21% of all clicks, respectively. The seasonal patterns were not very strong except in the SW location with distinct peak in detection during the months of April–June 2010 period.
Intraglottal geometry and velocity measurements in canine larynges
Authors: Oren Liran , Khosla Sid , Gutmark Ephraim
Published: January 2014

Previous flow velocity measurements during phonation in canine larynges were done above the glottal exit. These studies found that vortical structures are present in the flow above the glottis at different phases of the glottal cycle. Some vortices were observed to leave the glottis during the closing phase and assumptions were proposed regarding their formation mechanism. In the current study, intraglottal velocity measurements are performed using PIV, and the intraglottal flow characteristics are determined. Results from five canine larynges show that at low subglottal pressure the glottis assumes a minimal divergence angle during closing and the flow separates at the glottal exit. Vortical structures are observed above the glottis but not inside. As the subglottal pressure is increased, the divergence angle between the folds during closing increases and the location of the flow separation moves upstream into the glottis. Entrainment flow enters the glottis to fill the void that is formed between the glottal jet and the fold. Vortical structures develop near the superior edge at medium and high subglottal pressures from the flow separation. The magnitude of their swirling strength changes as a function of the wall dynamics.
Contribution of low-frequency harmonics to Mandarin Chinese tone identification in quiet and six-talker babble background
Authors: Liu Chang , Azimi Behnam , Bhandary Moulesh , Hu Yi
Published: January 2014

The goal of this study was to investigate Mandarin Chinese tone identification in quiet and multi-talker babble conditions for normal-hearing listeners. Tone identification was measured with speech stimuli and stimuli with low and/or high harmonics that were embedded in three Mandarin vowels with two fundamental frequencies. There were six types of stimuli: all harmonics (All), low harmonics (Low), high harmonics (High), and the first (H1), second (H2), and third (H3) harmonic. Results showed that, for quiet conditions, individual harmonics carried frequency contour information well enough for tone identification with high accuracy; however, in noisy conditions, tone identification with individual low harmonics (e.g., H1, H2, and H3) was significantly lower than that with the Low, High, and All harmonics. Moreover, tone identification with individual harmonics in noise was lower for a low F0 than for a high F0, and was also dependent on vowel category. Tone identification with individual low-frequency harmonics was accounted for by local signal-to-noise ratios, indicating that audibility of harmonics in noise may play a primary role in tone identification.
The effects of age and hearing loss on interaural phase difference discrimination
Authors: King Andrew , Hopkins Kathryn , Plack Christopher J.
Published: January 2014

The discrimination of interaural phase differences (IPDs) requires accurate binaural temporal processing and has been used as a measure of sensitivity to temporal envelope and temporal fine structure (TFS). Previous studies found that TFS-IPD discrimination declined with age and with sensorineural hearing loss (SNHL), but age and SNHL have often been confounded. The aim of this study was to determine the independent contributions of age and SNHL to TFS and envelope IPD discrimination by using a sample of adults with a wide range of ages and SNHL. A two-interval, two-alternative forced-choice procedure was used to measure IPD discrimination thresholds for 20-Hz amplitude-modulated tones with carrier frequencies of 250 or 500 Hz when the IPD was in either the stimulus envelope or TFS. There were positive correlations between absolute thresholds and TFS-IPD thresholds, but not envelope-IPD thresholds, when age was accounted for. This supports the idea that SNHL affects TFS processing independently to age. Age was positively correlated with envelope-IPD thresholds at both carrier frequencies and TFS-IPD thresholds at 500 Hz, when absolute thresholds were accounted for. These results suggest that age negatively affects the binaural processing of envelope and TFS at some frequencies independently of SNHL.
Sonar target enhancement by shrinkage of incoherent wavelet coefficients
Authors: Hunter Alan J. , van Vossen Robbert
Published: January 2014

Background reverberation can obscure useful features of the target echo response in broadband low-frequency sonar images, adversely affecting detection and classification performance. This paper describes a resolution and phase-preserving means of separating the target response from the background reverberation noise using a coherence-based wavelet shrinkage method proposed recently for de-noising magnetic resonance images. The algorithm weights the image wavelet coefficients in proportion to their coherence between different looks under the assumption that the target response is more coherent than the background. The algorithm is demonstrated successfully on experimental synthetic aperture sonar data from a broadband low-frequency sonar developed for buried object detection.
Combining whistle acoustic parameters to discriminate Mediterranean odontocetes during passive acoustic monitoring
Authors: Azzolin Marta , Gannier Alexandre , Lammers Marc O. , Oswald Julie N. , Papale Elena , Buscaino Giuseppa , Buffa Gaspare , Mazzola Salvatore , Giacoma Cristina
Published: January 2014

Acoustic observation can complement visual observation to more effectively monitor occurrence and distribution of marine mammals. For effective acoustic censuses, calibration methods must be determined by joint visual and acoustic studies. Research is still needed in the field of acoustic species identification, particularly for smaller odontocetes. From 1994 to 2012, whistles of four odontocete species were recorded in different areas of the Mediterranean Sea to determine how reliably these vocalizations can be classified to species. Recordings were attributed to species by simultaneous visual observation. The results of this study highlight that the frequency parameters, which are linked to physical features of animals, show lower variability than modulation parameters, which are likely to be more dependent on complex eco-ethological contexts. For all the studied species, minimum and maximum frequencies were linearly correlated with body size. DFA and Classification Tree Analysis (CART) show that these parameters were the most important for classifying species; however, both statistical methods highlighted the need for combining them with the number of contour minima and contour maxima for correct classification. Generally, DFA and CART results reflected both phylogenetic distance (especially for common and striped dolphins) and the size of the species.
Spin Exercise Improves Semantic Fluency in Previously Sedentary Older Adults
Authors: Nocera Joe R. , McGregor Keith M. , Hass Chris J. , Crosson Bruce
Published: January 2014

Studies suggest improvements of neurocognitive function among older adults who undergo aerobic exercise training. This study sought to examine the impact of an aerobic exercise intervention on verbal fluency in sedentary older adults. Twenty community-dwelling older adults were recruited and enrolled in either a spin exercise group or a control condition. Participants were evaluated with an estimated V02max test and on measures of letter, category, and switching verbal fluency both before and after a 12-week intervention period. Spin exercise resulted in a significant improvement in category (semantic) verbal fluency when compared with the control group (15% vs. 2% increase, respectively; P = .001). Spin exercise also resulted in a significant improvement in estimated V02max (P = .005). Also important, the spin exercise group demonstrated a high level of adherence (mean adherence = 82.5%). Spin exercise can be an effective mode of aerobic exercise to improve semantic fluency in previously sedentary older adults.
Telavancin for Hospital-Acquired Pneumonia: Clinical Response and 28-Day Survival
Authors: Corey G. Ralph , Kollef Marin H. , Shorr Andrew F. , Rubinstein Ethan , Stryjewski Martin E. , Hopkins Alan , Barriere Steven L.
Published: January 2014

U.S. Food and Drug Administration draft guidance for future antibiotic clinical trials of bacterial nosocomial pneumonia recommends the use of diagnostic criteria according to American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines and the use of a primary endpoint of 28-day all-cause mortality. The effect of applying these guidelines on outcomes of phase III nosocomial pneumonia studies of telavancin was evaluated in a
post hoc
analysis. ATS/IDSA criteria were applied in a blind fashion to the original all-treated (AT) group. Clinical cure rates at final follow-up were determined in the refined AT and clinically evaluable (CE) groups (ATS/IDSA-AT and ATS/IDSA-CE, respectively). The exploratory endpoint of 28-day survival was evaluated for the ATS/IDSA-AT group. Noninferiority of telavancin versus vancomycin was demonstrated, with similar cure rates in the ATS/IDSA-AT (59% versus 59%) and ATS/IDSA-CE (83% versus 80%) groups. Cure rates favored telavancin in ATS/IDSA-CE patients where
Staphylococcus aureus
was the sole pathogen (86% versus 75%). Overall, 28-day survival rates were similar in the telavancin (76%) and vancomycin (77%) groups but lower in telavancin-treated patients with preexisting moderate-to-severe renal impairment (creatinine clearance [CL
CR
] of <50 ml/min). Telavancin should be administered to patients with moderate-to-severe renal impairment only if treatment benefit outweighs the risk or if no suitable alternatives are available.
Early Entecavir Treatment for Chronic Hepatitis B with Severe Acute Exacerbation
Authors: Tsai Wei-Lun , Chiang Po-Hung , Chan Hoi-Hung , Lin Huey-Shyan , Lai Kwok-Hung , Cheng Jin-Shiung , Chen Wen-Chi , Tsay Feng-Woei , Wang Huay-Min , Tsai Tzung-Jiun , Yu Hsien-Chung , Hsu Ping-I
Published: January 2014

A previous study found that lamivudine, if started early enough, may improve the chance of survival in chronic hepatitis B virus (HBV) with severe acute exacerbation (SAE). The aim of this study was to investigate the effect of early entecavir treatment before the bilirubin level exceeds 20 mg/dl for chronic HBV with SAE. Consecutive patients with chronic HBV with SAE and a serum bilirubin level of <20 mg/dl who received lamivudine or entecavir were enrolled. Short-term (4 months) survival was evaluated. One hundred fourteen patients received lamivudine, and 53 patients received entecavir. The baseline characteristics were similar for the two groups except that the entecavir group was older and had a lower alanine aminotransferase (ALT) level. Three patients (8.0%) in the entecavir group and 9 patients (7.9%) in the lamivudine group died (
P
= 1.000). If only patients who started antiviral treatment before serum bilirubin level rose to more than 15 mg/dl were included, 3 patients (8.3%) in the entecavir group and 3 patients (3.0%) in the lamivudine group died (
P
= 0.189). If only patients with an HBV DNA level higher than 10
5
copies/ml and a bilirubin level lower than 15 mg/dl were included, 5 out of 40 patients (12.5%) in the entecavir group died and 1 out of 59 patients (1.7%) in the lamivudine group died. Multivariate analysis found that entecavir treatment was associated with more mortality than lamivudine (
P
= 0.035). Early entecavir treatment in patients with high viral load is associated with more short-term mortality than lamivudine for chronic HBV with severe acute exacerbation.
The Type VI Secretion System Spike Protein VgrG5 Mediates Membrane Fusion during Intercellular Spread by Pseudomallei Group Burkholderia Species
Authors: Toesca Isabelle J. , French Christopher T. , Miller Jeff F.
Published: January 2014

Pseudomallei group
Burkholderia
species are facultative intracellular parasites that spread efficiently from cell to cell by a mechanism involving the fusion of adjacent cell membranes. Intercellular fusion requires the function of the cluster 5 type VI secretion system (T6SS-5) and its associated valine-glycine repeat protein, VgrG5. Here we show that VgrG5 alleles are conserved and functionally interchangeable between
Burkholderia pseudomallei
and its relatives
B. mallei
,
B. oklahomensis
, and
B. thailandensis
. We also demonstrate that the integrity of the VgrG5 C-terminal domain is required for fusogenic activity, and we identify sequence motifs, including two hydrophobic segments, that are important for fusion. Mutagenesis and secretion experiments using
B. pseudomallei
strains engineered to express T6SS-5
in vitro
show that the VgrG5 C-terminal domain is dispensable for T6SS-mediated secretion of Hcp5, demonstrating that the ability of VgrG5 to mediate membrane fusion can be uncoupled from its essential role in type VI secretion. We propose a model in which a unique fusogenic activity at the C terminus of VgrG5 facilitates intercellular spread by
B. pseudomallei
and related species following injection across the plasma membranes of infected cells.
Helicobacter pylori Membrane Vesicles Stimulate Innate Pro- and Anti-Inflammatory Responses and Induce Apoptosis in Jurkat T Cells
Authors: Winter Jody , Letley Darren , Rhead Joanne , Atherton John , Robinson Karen
Published: January 2014

Persistent
Helicobacter pylori
infection induces chronic inflammation in the human gastric mucosa, which is associated with development of peptic ulceration, gastric atrophy, and gastric adenocarcinoma. It has been postulated that secretion of immunomodulatory molecules by
H. pylori
facilitates bacterial persistence, and membrane vesicles (MV), which have the potential to cross the gastric epithelial barrier, may mediate delivery of these molecules to host immune cells. However, bacterial MV effects on human immune cells remain largely uncharacterized to date. In the present study, we investigated the immunomodulatory effects of
H. pylori
MV with and without the vacuolating cytotoxin, VacA, which inhibits human T cell activity. We show a high degree of variability in the toxin content of vesicles between two
H. pylori
strains (SS1 and 60190). Vesicles from the more toxigenic 60190 strain contain more VacA (s1i1 type) than vesicles from the SS1 strain (s2i2 VacA), but engineering the SS1 strain to produce s1i1 VacA did not increase the toxin content of its vesicles. Vesicles from all strains tested, including a 60190 isogenic mutant null for VacA, strongly induced interleukin-10 (IL-10) and IL-6 production by human peripheral blood mononuclear cells independently of the infection status of the donor. Finally, we show that
H. pylori
MV induce T cell apoptosis and that this is enhanced by, but not completely dependent on, the carriage of VacA. Together, these findings suggest a role for
H. pylori
MV in the stimulation of innate pro- and anti-inflammatory responses and in the suppression of T cell immunity.
The effects of plastic spectacles on the condition and behaviour of pheasants
Authors: Butler D. A. , Davis C.
Published: January 2014

Plastic spectacles are often fitted to pheasants in laying pens to reduce feather pecking and egg eating. This study examined the effects of spectacles on the physiological condition and behaviour of pheasants in harem and flock laying pens. In 2006 and 2007, data were collected from 21 game farms across England. On each site, two identical pens were randomly allocated a treatment, with or without spectacles. The physiological condition of pheasants in each treatment pen was assessed before and after the laying season. In flock pens, the behaviour of spectacled and non‐spectacled pheasants was also assessed weekly. Detailed records of egg collections and mortality were also kept. Spectacles had no effect on the behaviour of male pheasants but affected the behaviour of females by reducing pecking and increasing head shaking/scratching. Although spectacles halved feather damage in females, and at least halved incidences of skin damage in both sexes, they increased bill and nostril damage in females while causing no detectable damage in males. Egg collections and mortality rates did not differ between spectacled and non‐spectacled pens.
Assessing the environmental impact of shredded tires as embankment fill material
Authors: Hennebert P. , Lambert S. , Fouillen F. , Charrasse B.
Published: January 2014

This article deals with the assessment of the environmental impact of shredded scrap tires mixed with sand to build embankments. Pollution of water as well as consequences of fire ignition were considered. Percolation, lixiviation, and lysimeter tests were performed on the raw material as well as on residue resulting from the fire. The collected liquids were analysed considering 200 physicochemical parameters. Their toxicity on a small shellfish and a bacterium was assessed. Measurements were compared with existing regulations and recommendations. Fire propagation risk in the core of the embankment and on the surface was also investigated. Measurements confirmed the limited consequences on the environment except in the case of fire, where residue must be considered hazardous waste.
Comparative analysis of the neuroprotective effects of ginsenosides Rg1 and Rb1 extracted fromPanax notoginsengagainst cerebral ischemia
Authors: Zeng Xian-Si , Zhou Xiao-Shuang , Luo Fu-Cheng , Jia Jin-Jing , Qi Lei , Yang Zhao-Xiang , Zhang Wei , Bai Jie
Published: January 2014

Panax notoginseng, a traditional Chinese medicine, has been used for thousands of years to treat ischemic patients. More than 20 saponin components have been isolated from P. notoginseng root and identified chemically. However, these different chemical components have different roles. In this study we compared the neuroprotective mechanisms of ginsenosides Rg1, Rb1, Rg1/Rb1, and panax notoginsenoside (PNS) against injuries caused by cerebral ischemia–reperfusion (I/R). Our results show that all of these treatments significantly reduced infarction volume and alleviated neurological deficits caused by cerebral I/R. The increase in malondialdehyde (MDA) concentration was inhibited by these treatments in the hippocampus. The decreased expressions of thioredoxin-1 (Trx-1), copper–zinc superoxide dismutase (SOD-1), protein kinase B (PKB/Akt), and nuclear factor-kappa B (NF-κB) caused by cerebral I/R were restored by these treatments. The expression of heat shock protein 70 (HSP70) was enhanced in the middle cerebral artery occlusion (MCAO) group, as well as in all of the treatment groups. These results suggest that Rg1 and Rb1 have similar roles in protecting the brain from ischemic damage; however, neither Rg1/Rb1 nor PNS have synergistic effects, thus either Rg1 or the Rb1 monomer should be considered as a pharmacological neuroprotective strategy for use in the case of ischemic stroke.
EFFECTS OF NEW VISCOSITY MODEL ON COSMOLOGICAL EVOLUTION
Authors: WANG JIAXIN , MENG XINHE
Published: January 2014

Bulk viscosity has been intrinsically existing in the observational cosmos evolution with various effects for different cosmological evolution stages endowed with complicated cosmic media. Normally in the idealized "standard cosmology", the physical viscosity effect is often negligent to some extent by assumptions, except for galaxies formation and evolution or like the astro-physics phenomena. Actually we have not fully understood the physical origin and effects of cosmic viscosity, including its functions for the universe evolution in reality. In this paper, we extend the concept of temperature-dependent viscosity from classical statistical physics to observational cosmology, especially we examine the cosmological effects with the possibility of existence for two kinds of viscosity forms, which are described by the Chapman's relation and Sutherland's formula, respectively. By considering that a modification of Standard Model with viscosity named as ΛCDM-V model is constructed, which is acceptable according to astrophysical observations. In addition to the enhancement to cosmic age value, the ΛCDM-V model possesses other two pleasing features: the prediction about the no-rip/singularity future and the mechanism of smooth transition from imperfect cosmological models to perfect ones.
MAGNETIC INDUCTION DEPENDENCE OF THE DISPERSION OF MAGNETOPLASMON IN A TWO-DIMENSIONAL ELECTRON GAS WITH FINITE LAYER THICKNESS
Authors: UCHIDA T. , HIRAIWA N. , YAMADA K. , FUJITA M. , TOYODA T.
Published: January 2014

Magnetic induction dependence of the dispersion of longitudinal magnetoplasmon in a two-dimensional electron gas with finite layer thickness under a static uniform magnetic field normal to the layer plane is calculated using the self-consistent linear response approximation. Two longitudinal magnetoplasmon modes are obtained. The calculated dispersion agrees with the experiment by Batke et al. [Phys. Rev. B34, 6951 (1986)].
PHOTOPRODUCTION OF PHI MESON NEAR THE THRESHOLD
Authors: RYU HUIYOUNG , HOSAKA ATSUSHI , KIM HYUN-CHUL , TITOV A. I.
Published: January 2014

Photoproduction of ϕ, γp → ϕ + p, is revisited in a model with Pomeron and hadron degrees of freedom. The scattering equation is written such that the final state interaction is included at the one-loop level of hadrons. We find a parameter set to reproduce the bump-like structure near the threshold in a way consistent with other meson production data.
MESON BARYON COMPONENTS IN THE STATES OF THE BARYON DECUPLET
Authors: ACETI F. , OSET E. , DAI L. R. , ZHANG Y. , GENG L. S.
Published: January 2014

We extend the Weinberg compositeness condition to partial waves of L = 1 and resonant states to determine the weight of meson-baryon component in the [Formula: see text] baryon decuplet. We obtain an appreciable weight of πN in the Δ(1232) wave function, of the order of 60 % and we also show that, as we go to higher energies in the members of the decuplet, the weights of meson-baryon component decrease and they already show a dominant part for a genuine component in the wave function. We interpret the meaning of the Weinberg sum-rule extended to complex energies.
INCOMPLETENESS OF COMPLETE KAON PHOTOPRODUCTION
Authors: RYCKEBUSCH JAN , VRANCX TOM
Published: January 2014

A possible roadmap for reaching a status of complete information in γp → K+Λ is outlined.
RELATIVISTIC QUARK-DIQUARK MODEL
Authors: FERRETTI J.
Published: January 2014

We discuss our relativistic quark-diquark model, developed in the framework of point form dynamics. Our results for the nonstrange baryon spectrum and for the nucleon electromagnetic form factors are discussed.
EXCITED BARYONS IN A COVARIANT THREE-BODY BETHE-SALPETER APPROACH
Authors: SANCHIS-ALEPUZ HÈLIOS , KUBRAK STANISLAV , FISCHER CHRISTIAN
Published: January 2014

We present first results for the excited nucleon spectrum in the framework of Poincaré-covariant three-body Bethe-Salpeter equations using the Rainbow-Ladder truncation of the interaction kernel. As expected, this truncation does not provide the mechanisms for a correct description of the spectrum. We also comment on possible steps beyond Rainbow-Ladder.
FTMP-BASED SIMULATION OF TWIN NUCLEATION AND SUBSTRUCTURE EVOLUTION UNDER HYPERVELOCITY IMPACT
Authors: OKUDA TATSUYA , IMIYA KAZUHIRO , HASEBE TADASHI
Published: January 2014

The deformation twinning model based on Field Theory of Multiscale Plasticity (FTMP) represents the twin degrees of freedom with the incompatibility tensor, which is incorporated into the hardening law of the FTMP-based crystalline plasticity framework. The model is further implemented into a finite element code. In the present study, the model is adapted to a single slip-oriented FCC single crystal sample, and preliminary simulations are conducted under static conditions to confirm the model's basic capabilities. The simulation results exhibit nucleation and growth of twinned regions, accompanied by serrated stress response and overall softening. Simulations under hypervelocity impact conditions are also conducted to investigate the model's descriptive capabilities of induced complex substructures composing of both twins and dislocations. The simulated nucleation of twins is examined in detail by using duality diagrams in terms of the flow-evolutionary hypothesis.
Peer and self assessment in massive online classes
Authors: Kulkarni Chinmay , Wei Koh Pang , Le Huy , Chia Daniel , Papadopoulos Kathryn , Cheng Justin , Koller Daphne , Klemmer Scott R.
Published: January 2014

Peer and self-assessment offer an opportunity to scale both assessment and learning to global classrooms. This article reports our experiences with two iterations of the first large online class to use peer and self-assessment. In this class, peer grades correlated highly with staff-assigned grades. The second iteration had 42.9% of students’ grades within 5% of the staff grade, and 65.5% within 10%. On average, students assessed their work 7% higher than staff did. Students also rated peers’ work from their own country 3.6% higher than those from elsewhere. We performed three experiments to improve grading accuracy. We found that giving students feedback about their grading bias increased subsequent accuracy. We introduce short, customizable feedback snippets that cover common issues with assignments, providing students more qualitative peer feedback. Finally, we introduce a data-driven approach that highlights high-variance items for improvement. We find that rubrics that use a parallel sentence structure, unambiguous wording, and well-specified dimensions have lower variance. After revising rubrics, median grading error decreased from 12.4% to 9.9%.
Information flow tracking meets just-in-time compilation
Authors: Kerschbaumer Christoph , Hennigan Eric , Larsen Per , Brunthaler Stefan , Franz Michael
Published: January 2014

Web applications are vulnerable to cross-site scripting attacks that enable data thefts. Information flow tracking in web browsers can prevent communication of sensitive data to unintended recipients and thereby stop such data thefts. Unfortunately, existing solutions have focused on incorporating information flow into browsers’ JavaScript interpreters, rather than just-in-time compilers, rendering the resulting performance noncompetitive. Few users will switch to a safer browser if it comes at the cost of significantly degrading web application performance.

We present the first information flow tracking JavaScript engine that is based on a true just-in-time compiler, and that thereby outperforms all previous interpreter-based information flow tracking JavaScript engines by more than a factor of two. Our JIT-based engine (i) has the same coverage as previous interpreter- based solutions, (ii) requires reasonable implementation effort, and (iii) introduces new optimizations to achieve acceptable performance. When evaluated against three industry-standard JavaScript benchmark suites, there is still an average slowdown of 73% over engines that do not support information flow, but this is now well within the range that many users will find an acceptable price for obtaining substantially increased security.
Time- and space-efficient flow-sensitive points-to analysis
Authors: Nasre Rupesh
Published: January 2014

Compilation of real-world programs often requires hours. The term
nightly build
known to industrial researchers is an artifact of long compilation times. Our goal is to reduce the absolute analysis times for large C codes (of the order of millions of lines). Pointer analysis is one of the key analyses performed during compilation. Its scalability is paramount to achieve the efficiency of the overall compilation process and its precision directly affects that of the client analyses. In this work, we design a time- and space-efficient flow-sensitive pointer analysis and parallelize it on graphics processing units. Our analysis proposes to use an extended bloom filter, called multibloom, to store points-to information in an approximate manner and develops an analysis in terms of the operations over the multibloom. Since bloom filter is a probabilistic data structure, we develop ways to gain back the analysis precision. We achieve effective parallelization by achieving memory coalescing, reducing thread divergence, and improving load balance across GPU warps. Compared to a state-of-the-art sequential solution, our parallel version achieves a 7.8 × speedup with less than 5% precision loss on a suite of six large programs. Using two client transformations, we show that this loss in precision only minimally affects a client’s precision.
ReSense
Authors: Dey Tanima , Wang Wei , Davidson Jack W. , Soffa Mary Lou
Published: January 2014

To utilize the full potential of modern chip multiprocessors and obtain scalable performance improvements, it is critical to mitigate resource contention created by multithreaded workloads. In this article, we describe ReSense, the first runtime system that uses application characteristics to dynamically map multithreaded applications from dynamic workloads—workloads where multithreaded applications arrive, execute, and terminate continuously in unpredictable ways. ReSense mitigates contention for the shared resources in the memory hierarchy by applying a novel thread-mapping algorithm that dynamically adjusts the mapping of threads from dynamic workloads using a precalculated sensitivity score. The sensitivity score quantifies an application's sensitivity to sharing a particular memory resource and is calculated by an efficient characterization process that involves running the multithreaded application by itself on the target platform. To measure ReSense's effectiveness, sensitivity scores were determined for 21 benchmarks from PARSEC-2.1 and NPB-OMP-3.3 for the shared resources in the memory hierarchy on four different platforms. Using three different-sized dynamic workloads composed of randomly selected two, four, and eight corunning benchmarks with randomly selected start times, ReSense was able to improve the average response time of the three workloads by up to 27.03%, 20.89%, and 29.34% and throughput by up to 19.97%, 46.56%, and 29.86%, respectively, over the native OS on real hardware. By estimating and comparing ReSense's effectiveness with the optimal thread mapping for two different workloads, we found that the maximum average difference with the experimentally determined optimal performance was 1.49% for average response time and 2.08% for throughput.
Techniques to improve performance in requester-wins hardware transactional memory
Authors: Armejach Adrià , Titos-Gil Ruben , Negi Anurag , Unsal Osman S. , Cristal Adrián
Published: January 2014

The simplicity of requester-wins Hardware Transactional Memory (HTM) makes it easy to incorporate in existing chip multiprocessors. Hence, such systems are expected to be widely available in the near future. Unfortunately, these implementations are prone to suffer severe performance degradation due to transient and persistent livelock conditions. This article shows that existing techniques are unable to mitigate this degradation effectively. It then proposes and evaluates four novel techniques—two software-based that employ information provided by the hardware and two that require simple core-local hardware additions—which have the potential to boost the performance of requester-wins HTM designs substantially.
PCantorSim
Authors: Jiang Chuntao , Yu Zhibin , Jin Hai , Xu Chengzhong , Eeckhout Lieven , Heirman Wim , Carlson Trevor E. , Liao Xiaofei
Published: January 2014

Computer architects rely heavily on microarchitecture simulation to evaluate design alternatives. Unfortunately, cycle-accurate simulation is extremely slow, being at least 4 to 6 orders of magnitude slower than real hardware. This longstanding problem is further exacerbated in the multi-/many-core era, because single-threaded simulation performance has not improved much, while the design space has expanded substantially. Parallel simulation is a promising approach, yet does not completely solve the simulation challenge. Furthermore, existing sampling techniques, which are widely used for single-threaded applications, do not readily apply to multithreaded applications as thread interaction and synchronization must now be taken into account. This work presents
PCantorSim
, a novel Cantor set (a classic fractal)--based sampling scheme to accelerate parallel simulation of multithreaded applications. Through the use of the proposed methodology, only less than 5% of an application's execution time is simulated in detail. We have implemented our approach in
Sniper
(a parallel multicore simulator) and evaluated it by running the PARSEC benchmarks on a simulated 8-core system. The results show that
PCantorSim
increases simulation speed over detailed parallel simulation by a factor of 20×, on average, with an average absolute execution time prediction error of 5.3%.
WADE
Authors: Wang Zhe , Shan Shuchang , Cao Ting , Gu Junli , Xu Yi , Mu Shuai , Xie Yuan , Jiménez Daniel A.
Published: January 2014

Emerging Non-Volatile Memory (NVM) technologies are explored as potential alternatives to traditional SRAM/DRAM-based memory architecture in future microprocessor design. One of the major disadvantages for NVM is the latency and energy overhead associated with write operations. Mitigation techniques to minimize the write overhead for NVM-based main memory architecture have been studied extensively. However, most prior work focuses on optimization techniques for NVM-based main memory itself, with little attention paid to cache management policies for the Last-Level Cache (LLC).

In this article, we propose a Writeback-Aware Dynamic CachE (WADE) management technique to help mitigate the write overhead in NVM-based memory.1 The proposal is based on the observation that, when dirty cache blocks are evicted from the LLC and written into NVM-based memory (with PCM as an example), the long latency and high energy associated with write operations to NVM-based memory can cause system performance/power degradation. Thus, reducing the number of writeback requests from the LLC is critical.

The proposed WADE cache management technique tries to keep highly reused dirty cache blocks in the LLC. The technique predicts blocks that are frequently written back in the LLC. The LLC sets are dynamically partitioned into a frequent writeback list and a nonfrequent writeback list. It keeps a best size of each list in the LLC. Our evaluation shows that the technique can reduce the number of writeback requests by 16.5% for memory-intensive single-threaded benchmarks and 10.8% for multicore workloads. It yields a geometric mean speedup of 5.1% for single-thread applications and 7.6% for multicore workloads. Due to the reduced number of writeback requests to main memory, the technique reduces the energy consumption by 8.1% for single-thread applications and 7.6% for multicore workloads.
TornadoNoC
Authors: Lee Junghee , Nicopoulos Chrysostomos , LEE Hyung Gyu , Kim Jongman
Published: January 2014

The rapid emergence of Chip Multi-Processors (CMP) as the de facto microprocessor archetype has highlighted the importance of scalable and efficient on-chip networks. Packet-based Networks-on-Chip (NoC) are gradually cementing themselves as the medium of choice for the multi-/many-core systems of the near future, due to their innate scalability. However, the prominence of the debilitating power wall requires the NoC to also be as energy efficient as possible. To achieve these two antipodal requirements—scalability and energy efficiency—we propose TornadoNoC, an interconnect architecture that employs a novel flow control mechanism. To prevent livelocks and deadlocks, a sequence numbering scheme and a dynamic ring inflation technique are proposed, and their correctness formally proven. The primary objective of TornadoNoC is to achieve substantial gains in (a)
scalability
to many-core systems and (b) the
area/power
footprint, as compared to current state-of-the-art router implementations. The new router is demonstrated to provide better scalability to hundreds of cores than an ideal single-cycle wormhole implementation and other scalability-enhanced low-cost routers. Extensive simulations using both synthetic traffic patterns and real applications running in a full-system simulator corroborate the efficacy of the proposed design. Finally, hardware synthesis analysis using commercial 65nm standard-cell libraries indicates that the area and power budgets of the new router are reduced by up to 53% and 58%, respectively, as compared to existing state-of-the-art low-cost routers.
Reducing instruction fetch energy in multi-issue processors
Authors: Gavin Peter , Whalley David , Själander Magnus
Published: January 2014

The need to minimize power while maximizing performance has led to recent developments of powerful superscalar designs targeted at embedded and portable use. Instruction fetch is responsible for a significant fraction of microprocessor power and energy, and is therefore an attractive target for architectural power optimization. We present novel techniques that take advantage of guarantees so that the instruction translation lookaside buffer, branch target buffer, and branch prediction buffer can frequently be disabled, reducing their energy usage, while simultaneously reducing branch predictor contention. These techniques require no changes to the instruction set and can easily be integrated into most single- and multiple-issue processors.
Crossover from Bardeen-Cooper-Schrieffer to Bose-Einstein Condensation and the Unitary Fermi Gas
Authors: Randeria Mohit , Taylor Edward
Published: January 2014

The crossover from weak-coupling Bardeen-Cooper-Schrieffer (BCS) pairing to a Bose-Einstein condensate (BEC) of tightly bound pairs, as a function of the attractive interaction in Fermi systems, has long been of interest to theoretical physicists. The past decade has seen a series of remarkable experimental developments in ultracold Fermi gases that have realized the BCS-BEC crossover in the laboratory, bringing with it fresh new insights into the very strongly interacting unitary regime in the middle of this crossover. In this review, we start with a pedagogical introduction to the crossover and then focus on recent progress in the strongly interacting regime. Although our focus is on new theoretical developments, we also describe three key experiments that probe the thermodynamics, transport, and spectroscopy of the unitary Fermi gas. We discuss connections between the unitary regime and other areas of physics—quark-gluon plasmas, gauge-gravity duality, and high-temperature superconductivity—and conclude with open questions about strongly interacting Fermi gases.