bluuebunny/crossref_metadata_2025 huggingface dataset:
KPC-Producing Klebsiella pneumoniae Strains That Harbor AAC(6′)-Ib Exhibit Intermediate Resistance to Amikacin
Authors: Bremmer Derek N. , Clancy Cornelius J. , Press Ellen G. , Almaghrabi Reem , Chen Liang , Doi Yohei , Nguyen M. Hong , Shields Ryan K.
Published: October 2014

The aminoglycoside-modifying enzyme AAC(6′)-Ib is common among carbapenem-resistant
Klebsiella pneumoniae
(CR-Kp) strains. We investigated amikacin (AMK) activity against 20 AAC(6′)-Ib-producing CR-Kp strains. MICs clustered at 16 to 32 μg/ml. By the time-kill study, AMK (1× and 4× the MIC) was bactericidal against 30% and 85% of the strains, respectively. At achievable human serum concentrations, however, the majority of strains showed regrowth, suggesting that AAC(6′)-Ib confers intermediate AMK resistance. AMK and trimethoprim-sulfamethoxazole (TMP-SMX) were synergistic against 90% of the strains, indicating that the combination may overcome resistance.
Oral Administration of the Broad-Spectrum Antibiofilm Compound Toremifene Inhibits Candida albicans and Staphylococcus aureus Biofilm Formation
In Vivo
Authors: De Cremer Kaat , Delattin Nicolas , De Brucker Katrijn , Peeters Annelies , Kucharíková Soña , Gerits Evelien , Verstraeten Natalie , Michiels Jan , Van Dijck Patrick , Cammue Bruno P. A. , Thevissen Karin
Published: October 2014

We here report on the
in vitro
activity of toremifene to inhibit biofilm formation of different fungal and bacterial pathogens, including
Candida albicans
,
Candida glabrata
,
Candida dubliniensis
,
Candida krusei
,
Pseudomonas aeruginosa
,
Staphylococcus aureus
, and
Staphylococcus epidermidis
. We validated the
in vivo
efficacy of orally administered toremifene against
C. albicans and S. aureus
biofilm formation in a rat subcutaneous catheter model. Combined, our results demonstrate the potential of toremifene as a broad-spectrum oral antibiofilm compound.
Pharmacokinetics, Biodistribution, and Toxicity of Folic Acid-Coated Antiretroviral Nanoformulations
Authors: Gautam Nagsen , Puligujja Pavan , Balkundi Shantanu , Thakare Rhishikesh , Liu Xin-Ming , Fox Howard S. , McMillan JoEllyn , Gendelman Howard E. , Alnouti Yazen
Published: October 2014

The drug delivery platform for folic acid (FA)-coated nanoformulated ritonavir (RTV)-boosted atazanavir (FA-nanoATV/r) using poloxamer 407 was developed to enhance cell and tissue targeting for a range of antiretroviral drugs. Such formulations would serve to extend the drug half-life while improving the pharmacokinetic profile and biodistribution to reservoirs of human immunodeficiency virus (HIV) infection. To this end, we now report enhanced pharmacokinetics and drug biodistribution with limited local and systemic toxicities of this novel nanoformulation. The use of FA as a targeting ligand for nanoATV/r resulted in plasma and tissue drug concentrations up to 200-fold higher compared to equimolar doses of native drug. In addition, ATV and RTV concentrations in plasma from mice on a folate-deficient diet were up to 23-fold higher for mice administered FA-nanoATV/r than for mice on a normal diet. Compared to earlier nanoATV/r formulations, FA-nanoATV/r resulted in enhanced and sustained plasma and tissue ATV concentrations. In a drug interaction study, ATV plasma and tissue concentrations were up to 5-fold higher in mice treated with FA-nanoATV/r than in mice treated with FA-nanoATV alone. As observed in mice, enhanced and sustained plasma concentrations of ATV were observed in monkeys. NanoATV/r was associated with transient local inflammation at the site of injection. There were no systemic adverse reactions associated with up to 10 weeks of chronic exposure of mice or monkeys to FA-nanoATV/r.
Abdominal Candidiasis Is a Hidden Reservoir of Echinocandin Resistance
Authors: Shields Ryan K. , Nguyen M. Hong , Press Ellen G. , Clancy Cornelius J.
Published: October 2014

FKS
mutant
Candida
isolates were recovered from 24% (6/25) of abdominal candidiasis patients exposed to echinocandin.
Candida glabrata
(29%) and
Candida albicans
(14%) mutants were identified. Multidrug-resistant bacteria were recovered from 83% of
FKS
mutant infections. Mutations were associated with prolonged echinocandin exposure (
P
= 0.01), breakthrough infections (
P
= 0.03), and therapeutic failures despite source control interventions (100%). Abdominal candidiasis is a hidden reservoir for the emergence of echinocandin-resistant
Candida
.
Transcription of the Streptococcus pyogenes Hyaluronic Acid Capsule Biosynthesis Operon Is Regulated by Previously Unknown Upstream Elements
Authors: Falaleeva Marina , Zurek Oliwia W. , Watkins Robert L. , Reed Robert W. , Ali Hadeel , Sumby Paul , Voyich Jovanka M. , Korotkova Natalia
Published: October 2014

The important human pathogen
Streptococcus pyogenes
(group A
Streptococcus
[GAS]) produces a hyaluronic acid (HA) capsule that plays critical roles in immune evasion. Previous studies showed that the
hasABC
operon encoding the capsule biosynthesis enzymes is under the control of a single promoter, P1, which is negatively regulated by the two-component regulatory system CovR/S. In this work, we characterize the sequence upstream of P1 and identify a novel regulatory region controlling transcription of the capsule biosynthesis operon in the M1 serotype strain MGAS2221. This region consists of a promoter, P2, which initiates transcription of a novel small RNA, HasS, an intrinsic transcriptional terminator that inefficiently terminates HasS, permitting read-through transcription of
hasABC
, and a putative promoter which lies upstream of P2. Electrophoretic mobility shift assays, quantitative reverse transcription-PCR, and transcriptional reporter data identified CovR as a negative regulator of P2. We found that the P1 and P2 promoters are completely repressed by CovR, and capsule expression is regulated by the putative promoter upstream of P2. Deletion of
hasS
or of the terminator eliminates CovR-binding sequences, relieving repression and increasing read-through,
hasA
transcription, and capsule production. Sequence analysis of 44 GAS genomes revealed a high level of polymorphism in the HasS sequence region. Most of the HasS variations were located in the terminator sequences, suggesting that this region is under strong selective pressure. We discovered that the terminator deletion mutant is highly resistant to neutrophil-mediated killing and is significantly more virulent in a mouse model of GAS invasive disease than the wild-type strain. Together, these results are consistent with the naturally occurring mutations in this region modulating GAS virulence.
Site-Specific Mutation of the Sensor Kinase GraS in Staphylococcus aureus Alters the Adaptive Response to Distinct Cationic Antimicrobial Peptides
Authors: Cheung Ambrose L. , Bayer Arnold S. , Yeaman Michael R. , Xiong Yan Q. , Waring Alan J. , Memmi Guido , Donegan Niles , Chaili Siyang , Yang Soo-Jin
Published: October 2014

The
Staphylococcus aureus
two-component regulatory system, GraRS, is involved in resistance to killing by distinct host defense cationic antimicrobial peptides (HD-CAPs). It is believed to regulate downstream target genes such as
mprF
and
dltABCD
to modify the
S. aureus
surface charge. However, the detailed mechanism(s) by which the histidine kinase, GraS, senses specific HD-CAPs is not well defined. Here, we studied a well-characterized clinical methicillin-resistant
S. aureus
(MRSA) strain (MW2), its isogenic
graS
deletion mutant (Δ
graS
strain), a nonameric extracellular loop mutant (ΔEL strain), and four residue-specific ΔEL mutants (D37A, P39A, P39S, and D35G D37G D41G strains). The Δ
graS
and ΔEL strains were unable to induce
mprF
and
dltA
expression and, in turn, demonstrated significantly increased susceptibilities to daptomycin, polymyxin B, and two prototypical HD-CAPs (hNP-1 and RP-1). Further, P39A, P39S, and D35G-D37G-D41G ΔEL mutations correlated with moderate increases in HD-CAP susceptibility. Reductions of
mprF
and
dltA
induction by PMB were also found in the ΔEL mutants, suggesting these residues are pivotal to appropriate activation of the GraS sensor kinase. Importantly, a synthetic exogenous soluble EL mimic of GraS protected the parental MW2 strain against hNP-1- and RP-1-mediated killing, suggesting a direct interaction of the EL with HD-CAPs in GraS activation.
In vivo
, the Δ
graS
and ΔEL strains displayed dramatic reductions in achieved target tissue MRSA counts in an endocarditis model. Taken together, our results provide new insights into potential roles of GraS in
S. aureus
sensing of HD-CAPs to induce adaptive survival responses to these molecules.
Massive surgical emphysema after perineal proctosigmoidectomy
Authors: Angehrn Fiorenzo Valente Ernst Jakob , Däster Silvio , Antonescu Marius
Published: October 2014

An 83-year-old woman underwent an elective perineal proctosigmoidectomy (Altemeier procedure) for a rectal prolapse. On postoperative day 1, the patient presented with impressive subcutaneous emphysema involving the chest, neck and face without any other symptoms. A CT scan showed free air in the retroperitoneum, the intraperitoneal cavity, the mediastinum and a subcutaneous emphysema of the neck and the face. Air was also found around the coloanal anastomosis and an anastomotic leak was proven by rectal contrast agent. In this situation, a rectoscopy followed by a laparoscopy were immediately performed. The leak could not be visualised. Peritoneal lavage and drainage, followed by protective sigmoidostomy were carried out. After surgery, the follow-up was uneventful except a persistent but asymptomatic leak with a presacral cavity. The coloanal dehiscence was later proven in rectoscopy. Although sutured, it is still present and colostomy closure will eventually be possible in a few months.
The Esophageal Pressure-Guided Ventilation 2 (EPVent2) trial protocol: a multicentre, randomised clinical trial of mechanical ventilation guided by transpulmonary pressure
Authors: Fish Emily , Novack Victor , Banner-Goodspeed Valerie M , Sarge Todd , Loring Stephen , Talmor Daniel
Published: October 2014

Introduction

Optimal ventilator management for patients with acute respiratory distress syndrome (ARDS) remains uncertain. Lower tidal volume ventilation appears to be beneficial, but optimal management of positive end-expiratory pressure (PEEP) remains unclear. The Esophageal Pressure-Guided Ventilation 2 Trial (EPVent2) aims to examine the impact of mechanical ventilation directed at maintaining a positive transpulmonary pressure (PTP) in patients with moderate-to-severe ARDS.

Methods and analysis

EPVent2 is a multicentre, prospective, randomised, phase II clinical trial testing the hypothesis that the use of a PTP-guided ventilation strategy will lead to improvement in composite outcomes of mortality and time off the ventilator at 28 days as compared with a high-PEEP control. This study will enrol 200 study participants from 11 hospitals across North America. The trial will utilise a primary composite end point that incorporates death and days off the ventilator at 28 days to test the primary hypothesis that adjusting ventilator pressure to achieve positive PTPvalues will result in improved mortality and ventilator-free days.

Ethics and dissemination

Safety oversight will be under the direction of an independent Data and Safety Monitoring Board (DSMB). Approval of the protocol was obtained from the DSMB prior to enrolling the first study participant. Approvals of the protocol as well as informed consent documents were also obtained from the Institutional Review Board of each participating institution prior to enrolling study participants at each respective site. The findings of this investigation, as well as associated ancillary studies, will be disseminated in the form of oral and abstract presentations at major national and international medical specialty meetings. The primary objective and other significant findings will also be presented in manuscript form. All final, published manuscripts resulting from this protocol will be submitted to PubMed Central in accordance with the National Institute of Health Public Access Policy.

Trial registration number

ClinicalTrials.gov under numberNCT01681225.
Disparities in cancer incidence and mortality by area-level socioeconomic status: a multilevel analysis
Authors: Hastert Theresa A , Beresford Shirley A A , Sheppard Lianne , White Emily
Published: October 2014

Background

Disparities in cancer incidence and mortality have been observed by measures of area-level socioeconomic status (SES); however, the extent to which these disparities are explained by individual SES is unclear.

Methods

Participants included 60 756 men and women in the VITamins And Lifestyle (VITAL) study cohort, aged 50–76 years at baseline (2000–2002) and followed through 2010. We constructed a block group SES index using the 2000 US Census and fit Cox proportional hazards models to estimate the association between area-level SES (by quintile) and total and site-specific cancer incidence and total cancer mortality, with and without household income and individual education in the models.

Results

Lower area-level SES was weakly associated with higher total cancer incidence and lower prostate cancer risk, but was not associated with risk of breast cancer. Compared with the highest-SES areas, living in the lowest-SES areas was associated with higher lung (HR: 2.21, 95% CI 1.69 to 2.90) and colorectal cancer incidence (HR: 1.52, 95% CI 1.11 to 2.09) and total cancer mortality (HR: 1.68, 95% CI 1.47 to 1.93). Controlling for individual education and household income weakened the observed associations, but did not eliminate them (lung cancer HR: 1.43, 95% CI 1.07 to 1.91; colorectal cancer HR: 1.35, 95% CI 0.97 to 1.88; cancer mortality HR: 1.28, 95% CI 1.11 to 1.48).

Conclusions

Area-level socioeconomic disparities exist for several cancer outcomes. These differences are not fully explained by individual SES, suggesting area-level factors may play a role.
The effect of recombinant human growth hormone and insulin-like growth factor-1 on the mitochondrial function and viability of peripheral blood mononuclear cells in vitro
Authors: Keane James , Tajouri Lotti , Gray Bon
Published: October 2014

This study investigated whether the putative physiological benefits induced by growth hormone (GH) and insulin-like growth factor-1 (IGF-1) are countered at supra-physiological concentrations because of an augmentation in the production of mitochondrial-derived free radicals with a subsequent increase in oxidative damage, compromising mitochondrial function. To test this hypothesis, peripheral blood mononuclear cells were incubated for 4 h with either recombinant human GH (rhGH) (range = 0.25–100 μg/L) or recombinant IGF-1 (rIGF-1) (range = 100–600 μg/L) and along with control samples were subsequently analyzed by flow cytometry for the determination of cellular viability, mitochondrial membrane potential (Δψm), mitochondrial superoxide (O2–) generation, and mitochondrial permeability transition pore (mtPTP) activity. Results showed levels of mitochondrial O2– generation to be significantly reduced compared with control samples (lymphocytes: 21.5 ± 1.6 AU; monocytes: 230.2 ± 9.8 AU) following rhGH treatment at both concentrations of 5 μg/L (13.5 ± 1.3 AU, P ≤ 0.05) and 10 μg/L (12.3 ± 1.5 AU, P ≤ 0.05) in lymphocytes and at 10 μg/L (153.4 ± 11.4 AU, P ≤ 0.05) in monocytes. However, no significant effect was found at either higher rhGH concentrations or following treatment with any concentration of rIGF-1. In addition, neither of the 2 hormones had any significant effect on Δψm, mtPTP activity, or on cellular viability. In conclusion, physiological concentrations of rhGH elicited a protective cellular effect through the reduction of oxidative free radicals within mitochondria. This antioxidant effect was diminished at supra-physiological concentrations but not to a level that would elicit disruption of mitochondrial function.
The effects of a protein osmolyte on the stability of the integral membrane protein glycerol facilitator
Authors: Baturin Simon , Galka Jamie J. , Piyadasa Hadeesha , Gajjeraman S. , O’Neil Joe D.
Published: October 2014

Osmolytes are naturally occurring molecules used by a wide variety of organisms to stabilize proteins under extreme conditions of temperature, salinity, hydrostatic pressure, denaturant concentration, and desiccation. The effects of the osmolyte trimethylamine N-oxide (TMAO) as well as the influence of detergent head group and acyl chain length on the stability of the Escherichia coli integral membrane protein glycerol facilitator (GF) tetramer to thermal and chemical denaturation by sodium dodecyl sulphate (SDS) are reported. TMAO promotes the association of the normally tetrameric α-helical protein into higher order oligomers in dodecyl-maltoside (DDM), but not in tetradecyl-maltoside (TDM), lyso-lauroylphosphatidyl choline (LLPC), or lyso-myristoylphosphatidyl choline (LMPC), as determined by dynamic light scattering (DLS); an octameric complex is particularly stable as indicated by SDS polyacrylamide gel electrophoresis. TMAO increases the heat stability of the GF tetramer an average of 10 °C in the 4 detergents and also protects the protein from denaturation by SDS. However, it did not promote re-association to the tetramer when added to SDS-dissociated protein. TMAO also promotes the formation of rod-like detergent micelles, and DLS was found to be useful for monitoring the structure of the protein and the redistribution of detergent during thermal dissociation of the protein. The protein is more thermally stable in detergents with the phosphatidylcholine head group (LLPC and LMPC) than in the maltoside detergents. The implications of the results for osmolyte mechanism, membrane protein stability, and protein–protein interactions are discussed.
Diversity of halophilic bacteria isolated from Rambla Salada, Murcia (Spain)
Authors: Luque Rocío , Béjar Victoria , Quesada Emilia , Llamas Inmaculada
Published: October 2014

In this study we analyzed the diversity of the halophilic bacteria community from Rambla Salada during the years 2006 and 2007. We collected a total of 364 strains, which were then identified by means of phenotypic tests and by the hypervariable V1–V3 region of the 16S rRNA sequences (around 500 bp). The ribosomal data showed that the isolates belonged to Proteobacteria (72.5%), Firmicutes (25.8%), Actinobacteria (1.4%), and Bacteroidetes (0.3%) phyla, with Gammaproteobacteria the predominant class. Halomonas was the most abundant genus (41.2% isolates) followed by Marinobacter (12.9% isolates) and Bacillus (12.6% isolates). In addition, 9 strains showed <97% sequence identity with validly described species and may well represent new taxa. The diversity of the bacterial community analyzed with the DOTUR package determined 139 operational taxonomic units at 3% genetic distance level. Rarefaction curves and diversity indexes demonstrated that our collection of isolates adequately represented all the bacterial community at Rambla Salada that can be grown under the conditions used in this work. We found that the sampling season influenced the composition of the bacterial community, and bacterial diversity was higher in 2007; this fact could be related to lower salinity at this sampling time.
Relativistic corrections to the central force problem in a generalized potential approach
Authors: Singh Ashmeet , Patra Binoy Krishna
Published: October 2014

We present a novel technique to obtain relativistic corrections to the central force problem in the Lagrangian formulation, using a generalized potential energy function. We derive a general expression for a generalized potential energy function for all powers of the velocity, which when made a part of the regular classical Lagrangian can reproduce the correct (relativistic) force equation. We then go on to derive the Hamiltonian and estimate the corrections to the total energy of the system up to the fourth power in |v|/c. We find a more comprehensive understanding of relativistic corrections to the central force results and provide corrections to both the kinetic and potential energy of the system. We employ our methodology to calculate relativistic corrections to the circular orbit under the gravitational force and also first-order corrections to the ground state energy of the hydrogen atom using a semiclassical approach. Our predictions in both problems give reasonable agreement with the known results. Thus we feel that this work has pedagogical value and can be used by undergraduate students to better understand the central force and the relativistic corrections to it.
Finding possibility of dynamical dark energy with Hubble parameters
Authors: Wang Jiaxin , Meng Xinhe
Published: October 2014

The Hubble parameter is a critical measurement in cosmology, which contains the most direct information of the cosmic expansion history. Since discrepancy is found between low redshift and high redshift estimations of Hubble constant, we are interested in whether that tension indicates dynamical dark energy. In this paper, we emphasize that the observed Hubble parameters at various redshifts, along with observed Hubble constant, can help us in probing the evolutional behavior of the mysterious dark energy. Null hypothesis tests are carried out with two diagnostic approaches. We find out that, according to the present measurements of Hubble parameters, rejection of constant dark energy is captured at 1σ level from null tests with and without the observed value of Hubble constant.
Chiral symmetry in SU(Nc) gauge theories at high density
Authors: Tomboulis E. T.
Published: October 2014

SU(Nc) lattice gauge theories with Nf flavors of massless staggered fermions are studied in the presence of quark chemical potential μ. A recent exact result that in the strong coupling limit (vanishing inverse gauge coupling β) and for sufficiently large μ the theory is in a chiral symmetric phase is here extended into the finite gauge coupling region. These and similar results are obtained by means of a cluster expansion which combines a fermion spacelike hopping expansion and a strong coupling plaquette expansion. The cluster expansion is shown to converge for sufficiently large μ and small β at any temperature T. All expectations of chirally noninvariant local fermion operators vanish identically, or, equivalently, their correlations cluster exponentially within the expansion. This implies the absence of spontaneous breaking of (any part of) the global chiral symmetries in the theory. The resulting phase at low T may be described as a "quarkyonic" matter phase. There is thus absence of any superfluidity or color superconductivity in this strong coupling regime. Implications for the phase diagram of SU(Nc) theories in the region of large chemical potential are discussed.
Anderson localization in QCD-like theories
Authors: Giordano Matteo , Kovács Tamás G. , Pittler Ferenc
Published: October 2014

We review the present status of the Anderson transition in the spectrum of the Dirac operator of QCD-like theories on the lattice. Localized modes at the low end of the spectrum have been found in SU(2) Yang–Mills theory with overlap and staggered valence fermions as well as in Nf = 2+1 QCD with staggered quarks. We draw an analogy between the transition from localized to delocalized modes in the Dirac spectrum and the Anderson transition in electronic systems. The QCD transition turns out to be in the same universality class as the transition in the corresponding Anderson model. We also speculate on the possible physical relevance of this transition to QCD at high temperature and the possible finite temperature phase transition in QCD-like models with different fermion contents.
IR fixed points in lattice field theories
Authors: Del Debbio L.
Published: October 2014

The existence of strongly-interacting infrared (IR) fixed points in gauge theories can be studied using field theories defined on a lattice. Besides their academic interest, it has been argued that these theories could be used as a starting point to construct viable models of electroweak symmetry breaking (EWSB). A quantitative description of the large-distance dynamics is mandatory in order to develop predictive models for phenomenology. In these notes, we discuss the theoretical foundations of IR conformality, and present possible ways to study the problem using the lattice formulation of gauge theories. An overview of current results and methods is discussed.
One, two, zero: Scales of strong interactions
Authors: Lombardo Maria Paola , Miura Kohtaroh , da Silva Tiago Nunes , Pallante Elisabetta
Published: October 2014

We discuss our results on QCD with a number of fundamental fermions ranging from zero to sixteen. These theories exhibit a wide array of fascinating phenomena which have been under close scrutiny, especially in recent years, first and foremost is the approach to conformality. To keep this review focused we have chosen scale generation, or lack thereof, as a guiding theme, however the discussion will be set in the general framework of the analysis of the phases and phase transitions of strong interactions at zero and nonzero temperature.
Non-Markovian dynamics of correlations: The composite effect of two channels and robust quantum correlation preserving by detuning
Authors: Ji Y. H. , Wan X. D.
Published: October 2014

We investigate the influence of the composite effect and information backflow effect in non-Markovian channel on the dynamics of quantum correlation including quantum entanglement and quantum discord. It is found that, the composite effect of independent channels is not only harmful to the maintenance of quantum correlation but also unfavorable for the maintenance of classic correlation. In a non-Markovian channel, by regulating the discord between qubit and the center frequency of cavity model, the time of quantum correlation and classical correlation of the system can be effectively prolonged. Thus, the quantum information processing can be achieved more easily under larger detuning.
Nonreciprocal perfect absorber based on an ultra-compact nonsymmetry cavity structure
Authors: Fang Yun-Tuan , He Han-Qing , Lin Zhi-Li
Published: October 2014

In this paper, the transmission and absorption properties of nonsymmetrical cavity structure with metal material have been studied through transfer matrix method and electromagnetic (EM) field simulations. The absorption is found to be dependent on the cavity resonance effect. For a nonsymmetrical structure, the EM wave can be totally absorbed from one incidence direction, at the same time the EM wave is totally reflected from the opposite incidence direction. The reasons of the nonreciprocal absorption are analyzed in detail.
Magnetic properties prediction of NdFeB magnets by using support vector regression
Authors: Cheng Wende
Published: October 2014

A novel model using support vector regression (SVR) combined with particle swarm optimization (PSO) was employed to construct mathematical model for prediction of the magnetic properties of the NdFeB magnets. The leave-one-out cross-validation (LOOCV) test results strongly supports that the generalization ability of SVR is high enough. Predicted results show that the mean absolute percentage error for magnetic remanence Br, coercivity Hcj and maximum magnetic energy product (BH) max are 0.53%, 3.90%, 1.73%, and the correlation coefficient (R2) is as high as 0.839, 0.967 and 0.940, respectively. This investigation suggests that the PSO-SVR is not only an effective and practical method to simulate the properties of NdFeB , but also a powerful tool to optimatize designing or controlling the experimental process.
Tuning the acoustic directional radiation by rotating square rods in two-dimensional phononic crystals
Authors: Li Jing , Wu Fugen , Zhong Huilin , Zhang Xin , Yao Yuanwei
Published: October 2014

Analysis is given to acoustic directional radiation tuned by rotating square rods in two-dimensional (2D) solid–fluid phononic crystals (PC). The contour line method is introduced which predicts how the acoustic waves propagate at different frequency. As a specific example, for the systems of steel rods with square cross-section in a water host, we employ this approach to the analysis of the directivity successfully. The directional radiation frequency of two lowest bands are studied in this paper. The results show that the directional radiation frequency can be turned in a wide range by rotating the square rods. While the directivity of acoustic propagation keeps unchanged when the acoustic directional radiation frequency is located in the same band. Moreover, PCs exhibit excellent characteristic of single radiation branch as a corner cut off in a finite structure. Our approach may supply a new way to tune the directional radiation frequency.
PROSPECTIVE STUDY ON THE MANAGEMENT OF TRIGGER FINGER
Authors: Choudhury Muntasir Mannan , Tay Shian Chao
Published: October 2014

Trigger finger is one of the very common conditions encountered in hand surgery. Currently, the treatment modes we offer in our clinics are combination therapy of topical NSAIDS, occupational therapy and splinting or invasive modes involving corticosteroid injections and trigger finger release.

This is a prospective review looking at the outcomes of the various initial treatment modules currently used for treating trigger fingers and the rate of surgery following non-surgical treatment.

From our study we have noted that 26% of the digits which were subjected to combination therapy eventually underwent surgery whereas 60% of digits which received corticosteroid injections underwent surgery. Even though our results comparing operation rates are not statistically significant, they appear to show that combination therapy was more effective in avoiding surgery than corticosteroid injection in lower grades of trigger.
Segmentation of ECG from Surface EMG Using DWT and EMD: A Comparison Study
Authors: Shahbakhti Mohammad , Heydari Elnaz , Luu Gia Thien
Published: October 2014

The electrocardiographic (ECG) signal is a major artifact during recording the surface electromyography (SEMG). Removal of this artifact is one of the important tasks before SEMG analysis for biomedical goals. In this paper, the application of discrete wavelet transform (DWT) and empirical mode decomposition (EMD) for elimination of ECG artifact from SEMG is investigated. The focus of this research is to reach the optimized number of decomposed levels using mean power frequency (MPF) by both techniques. In order to implement the proposed methods, ten simulated and three real ECG contaminated SEMG signals have been tested. Signal-to-noise ratio (SNR) and mean square error (MSE) between the filtered and the pure signals are applied as the performance indexes of this research. The obtained results suggest both techniques could remove ECG artifact from SEMG signals fair enough, however, DWT performs much better and faster in real data.
Quadratic Hamilton–Poisson systems on $\mathfrak{s}\mathfrak{e}(1, 1)^{*}_{-}$: The homogeneous case
Authors: Barrett Dennis I. , Biggs Rory , Remsing Claudiu C.
Published: October 2014

In this paper we consider quadratic Hamilton–Poisson systems on the semi-Euclidean Lie–Poisson space [Formula: see text]. The homogeneous positive semidefinite systems are classified; there are exactly six equivalence classes. In each case, the stability nature of the equilibrium states is determined. Explicit expressions for the integral curves are found. A characterization of the equivalence classes, in terms of the equilibria, is identified. Finally, the relation of this work to optimal control is briefly discussed.
Filter Depth and Cofiniteness of Local Cohomology Modules Defined by a Pair of Ideals
Authors: Tehranian Abolfazl , Pour Eshmanan Talemi Atiyeh
Published: October 2014

Let I, J be ideals of a commutative Noetherian local ring (R, 𝔪) and let M be a finite R-module. The f-depth of M with respect to I is the least integer r such that [Formula: see text] is not Artinian. In this paper we show that [Formula: see text] is the least integer such that the local cohomology module with respect to a pair of ideals I, J is not Artinian. As a consequence, it follows that [Formula: see text] is (I,J)-cofinite for all [Formula: see text]. In addition, we show that for a Serre subcategory 𝖲, if [Formula: see text] belongs to 𝖲 for all i > n and if 𝔟 is an ideal of R such that [Formula: see text] belongs to 𝖲, then the module [Formula: see text] belongs to 𝖲.
Cofiniteness of Local Cohomology Modules
Authors: Bahmanpour Kamal , Naghipour Reza , Sedghi Monireh
Published: October 2014

Let M be a non-zero finitely generated module over a commutative Noetherian local ring (R, 𝔪). In this paper we consider when the local cohomology modules are finitely generated. It is shown that if t ≥ 0 is an integer and [Formula: see text], then [Formula: see text] is not 𝔭-cofinite. Then we obtain a partial answer to a question raised by Huneke. Namely, if R is a complete local ring, then [Formula: see text] is finitely generated if and only if 0 ≤ n ∉ W, where [Formula: see text]. Also, we show that if J ⊆ I are 1-dimensional ideals of R, then [Formula: see text] is J-cominimax, and [Formula: see text] is finitely generated (resp., minimax) if and only if [Formula: see text] is finitely generated for all [Formula: see text] (resp., [Formula: see text]). Moreover, the concept of the J-cofiniteness dimension [Formula: see text] of M relative to I is introduced, and we explore an interrelation between [Formula: see text] and the filter depth of M in I. Finally, we show that if R is complete and dim M/IM ≠ 0, then [Formula: see text].
Chain Condition on Annihilators and Strongly Hopfian Property in Hurwitz Series Ring
Authors: Benhissi Ali
Published: October 2014

In this paper we study some properties of the Hurwitz series ring HA over a commutative ring A, such as the nilradical of HA and the chain condition on its annihilators. We provide an example showing that the last property does not pass from A to HA. A strongly Hopfian ring is a ring satisfying the chain condition on some type of annihilators. We give a large class of strongly Hopfian rings A such that HA are not strongly Hopfian.
The Zariski Topology on the Second Spectrum of a Module
Authors: Ansari-Toroghy H. , Farshadifar F.
Published: October 2014

Let R be a commutative ring and M be an R-module. The second spectrum Spec s(M) of M is the collection of all second submodules of M. We topologize Spec s(M) with Zariski topology, which is analogous to that for Spec (M), and investigate this topological space. For various types of modules M, we obtain conditions under which Spec s(M) is a spectral space. We also investigate Spec s(M) with quasi-Zariski topology.
BENEFITS OF COUPLING ENVIRONMENTAL ASSESSMENT AND ENVIRONMENTAL MANAGEMENT TO AID DISASTER RISK REDUCTION AND MANAGEMENT
Authors: DURNING BRIDGET
Published: October 2014

The tsunami which devastated Japan in 2011 highlighted the consequences of natural disasters on an area considered to be "best prepared" for such an event. Learning from the direct environmental, social and economic impacts and temporally and spatially displaced indirect global impacts, is important. When seeking to identify and mitigate the impact of proposed developments the process is carried out from two distinct perspectives: "before" and "after" implementation with environmental impact assessment and environmental management the main "instruments" on either side. Drawing on examples from financial institutions and disaster response agencies, this paper explores the theory that coupling the two "instruments" can aid disaster risk reduction and management. It concludes that there is no simple answer and that further research is needed to inform practice.
Physical View on the Interactions Between Cancer Cells and the Endothelial Cell Lining During Cancer Cell Transmigration and Invasion
Authors: Mierke Claudia T.
Published: October 2014

There exist many reviews on the biological and biochemical interactions of cancer cells and endothelial cells during the transmigration and tissue invasion of cancer cells. For the malignant progression of cancer, the ability to metastasize is a prerequisite. In particular, this means that certain cancer cells possess the property to migrate through the endothelial lining into blood or lymph vessels, and are possibly able to transmigrate through the endothelial lining into the connective tissue and follow up their invasion path in the targeted tissue. On the molecular and biochemical level the transmigration and invasion steps are well-defined, but these signal transduction pathways are not yet clear and less understood in regards to the biophysical aspects of these processes.

To functionally characterize the malignant transformation of neoplasms and subsequently reveal the underlying pathway(s) and cellular properties, which help cancer cells to facilitate cancer progression, the biomechanical properties of cancer cells and their microenvironment come into focus in the physics-of-cancer driven view on the metastasis process of cancers. Hallmarks for cancer progression have been proposed, but they still lack the inclusion of specific biomechanical properties of cancer cells and interacting surrounding endothelial cells of blood or lymph vessels. As a cancer cell is embedded in a special environment, the mechanical properties of the extracellular matrix also cannot be neglected. Therefore, in this review it is proposed that a novel hallmark of cancer that is still elusive in classical tumor biological reviews should be included, dealing with the aspect of physics in cancer disease such as the natural selection of an aggressive (highly invasive) subtype of cancer cells displaying a certain adhesion or chemokine receptor on their cell surface.

Today, the physical aspects can be analyzed by using state-of-the-art biophysical methods. Thus, this review will present current cancer research in a different light from a physical point of view with respect to cancer cell mechanics and the special and unique role of the endothelium on cancer cell invasion.

The physical view on cancer disease may lead to novel insights into cancer disease and will help to overcome the classical views on cancer. In addition, in this review it will be discussed how physics of cancer can help to reveal and propose the functional mechanism which cancer cells use to invade connective tissue and transmigrate through the endothelium to finally metastasize.

Finally, in this review it will be demonstrated how biophysical measurements can be combined with classical analysis approaches of tumor biology. The insights into physical interactions between cancer cells, the endothelium and the microenvironment may help to answer some "old," but still important questions in cancer disease progression.
Blood flow analysis in tapered stenosed arteries with pseudoplastic characteristics
Authors: Akbar Noreen Sher , Nadeem S.
Published: October 2014

In this paper, the blood flow through a tapered artery with a stenosis by considering axially non-symmetric but radially symmetric mild stenosis on blood flow characteristics is analyzed, assuming the flow is steady and blood is treated as Williamson fluid. Perturbation solutions have been evaluated for velocity, resistance impedance, wall shear stress and shearing stress at the stenosis throat. The graphical results of different type of tapered arteries (i.e. converging tapering, diverging tapering, non-tapered artery) have been examined for different parameters of interest.
Private Analysis of Graph Structure
Authors: Karwa Vishesh , Raskhodnikova Sofya , Smith Adam , Yaroslavtsev Grigory
Published: October 2014

We present efficient algorithms for releasing useful statistics about graph data while providing rigorous privacy guarantees. Our algorithms work on datasets that consist of relationships between individuals, such as social ties or email communication. The algorithms satisfy
edge differential privacy
, which essentially requires that the presence or absence of any particular relationship be hidden.

Our algorithms output approximate answers to
subgraph counting queries
. Given a query graph
H
, for example, a triangle,
k
-star, or
k
-triangle, the goal is to return the number of edge-induced isomorphic copies of
H
in the input graph. The special case of triangles was considered by Nissim et al. [2007] and a more general investigation of arbitrary query graphs was initiated by Rastogi et al. [2009]. We extend the approach of Nissim et al. to a new class of statistics, namely
k
-star queries. We also give algorithms for
k
-triangle queries using a different approach based on the higher-order local sensitivity. For the specific graph statistics we consider (i.e.,
k
-stars and
k
-triangles), we significantly improve on the work of Rastogi et al.: our algorithms satisfy a stronger notion of privacy that does not rely on the adversary having a particular prior distribution on the data, and add less noise to the answers before releasing them.

We evaluate the accuracy of our algorithms both theoretically and empirically, using a variety of real and synthetic datasets. We give explicit, simple conditions under which these algorithms add a small amount of noise. We also provide the average-case analysis in the Erdős-Rényi-Gilbert
G
(
n
,
p
) random graph model.

Finally, we give hardness results indicating that the approach Nissim et al. used for triangles cannot easily be extended to
k
-triangles (hence justifying our development of a new algorithmic approach).
Towards a Painless Index for Spatial Objects
Authors: Zhang Rui , Qi Jianzhong , Stradling Martin , Huang Jin
Published: October 2014

Conventional spatial indexes, represented by the R-tree, employ multidimensional tree structures that are complicated and require enormous efforts to implement in a full-fledged database management system (DBMS). An alternative approach for supporting spatial queries is mapping-based indexing, which maps both data and queries into a one-dimensional space such that data can be indexed and queries can be processed through a one-dimensional indexing structure such as the B
+
. Mapping-based indexing requires implementing only a few mapping functions, incurring much less effort in implementation compared to conventional spatial index structures. Yet, a major concern about using mapping-based indexes is their lower efficiency than conventional tree structures.

In this article, we propose a mapping-based spatial indexing scheme called
Size Separation Indexing
(SSI). SSI is equipped with a suite of techniques including size separation, data distribution transformation, and more efficient mapping algorithms. These techniques overcome the drawbacks of existing mapping-based indexes and significantly improve the efficiency of query processing. We show through extensive experiments that, for window queries on
spatial objects with nonzero extents
, SSI has two orders of magnitude better performance than existing mapping-based indexes and competitive performance to the R-tree as a standalone implementation. We have also implemented SSI on top of two off-the-shelf DBMSs, PostgreSQL and a commercial platform, both having R-tree implementation. In this case, SSI is up to two orders of magnitude faster than their provided spatial indexes. Therefore, we achieve a spatial index more efficient than the R-tree in a DBMS implementation that is at the same time easy to implement. This result may upset a common perception that has existed for a long time in this area that the R-tree is the best choice for indexing spatial objects.
Combating Software and Sybil Attacks to Data Integrity in Crowd-Sourced Embedded Systems
Authors: Dua Akshay , Bulusu Nirupama , Feng Wu-Chang , Hu Wen
Published: October 2014

Crowd-sourced mobile embedded systems allow people to contribute sensor data, for critical applications, including transportation, emergency response and eHealth. Data integrity becomes imperative as malicious participants can launch software and Sybil attacks modifying the sensing platform and data. To address these attacks, we develop (1) a Trusted Sensing Peripheral (TSP) enabling collection of high-integrity raw or aggregated data, and participation in applications requiring additional modalities; and (2) a Secure Tasking and Aggregation Protocol (STAP) enabling aggregation of TSP trusted readings by untrusted intermediaries, while efficiently detecting fabricators. Evaluations demonstrate that TSP and STAP are practical and energy-efficient.
QLib
Authors: Lin Chia-Chun , Chakrabarti Amlan , Jha Niraj K.
Published: October 2014

Quantum algorithms are known for their ability to solve some problems much faster than classical algorithms. They are executed on quantum circuits, which consist of a cascade of quantum gates. However, synthesis of quantum circuits is not straightforward because of the complexity of quantum algorithms.

Generally, quantum algorithms contain two parts: classical and quantum. Thus, synthesizing circuits for the two parts separately reduces overall synthesis complexity. In addition, many quantum algorithms use similar subroutines that can be implemented with similar circuit modules. Because of their frequent use, it is important to use automated scripts to generate such modules efficiently. These modules can then be subjected to further synthesis optimizations.

This article proposes QLib, a quantum module library, which contains scripts to generate quantum modules of different sizes and specifications for well-known quantum algorithms. Thus, QLib can also serve as a suite of benchmarks for quantum logic and physical synthesis.
Placement optimization of flexible TFT circuits with mechanical strain and temperature consideration
Authors: Lin Jiun-Li , Wu Po-Hsun , Ho Tsung-Yi
Published: October 2014

Mobility is the primary device parameter affecting circuit performance in flexible thin-film transistor (TFT) technologies, and is particularly sensitive to the change of mechanical strain and temperature. However, existing algorithms only consider the impact of mechanical strain in cell placement of flexible TFT circuits. Without taking temperature into consideration, mobility may be dramatically decreased which leads to circuit performance degradation. This article presents the first work to minimize the mobility variation caused by the change of both mechanical strain and temperature. Experimental results show that the proposed algorithms can effectively and efficiently reduce the increasing critical path delay.
Privacy-Preserving Ad-Hoc Equi-Join on Outsourced Data
Authors: Pang Hweehwa , Ding Xuhua
Published: October 2014

In IT outsourcing, a user may delegate the data storage and query processing functions to a third-party server that is not completely trusted. This gives rise to the need to safeguard the privacy of the database as well as the user queries over it. In this article, we address the problem of running ad hoc equi-join queries directly on encrypted data in such a setting. Our contribution is the first solution that achieves constant complexity per pair of records that are evaluated for the join. After formalizing the privacy requirements pertaining to the database and user queries, we introduce a cryptographic construct for securely joining records across relations. The construct protects the database with a strong encryption scheme. Moreover, information disclosure after executing an equi-join is kept to the minimum—that two input records combine to form an output record if and only if they share common join attribute values. There is no disclosure on records that are not part of the join result.

Building on this construct, we then present join algorithms that optimize the join execution by eliminating the need to match every record pair from the input relations. We provide a detailed analysis of the cost of the algorithms and confirm the analysis through extensive experiments with both synthetic and benchmark workloads. Through this evaluation, we tease out useful insights on how to configure the join algorithms to deliver acceptable execution time in practice.