bluuebunny/crossref_metadata_2025 huggingface dataset:
The Lyman α emission of high-z damped Lyman α systems
Authors: Rahmani H. , Srianand R. , Noterdaeme P. , Petitjean P.
Published: October 2010

Using a spectral stacking technique we searched for the average Lyman α (Lyα) emission from high-z damped Lyα (DLA) galaxies detected in the Sloan Digital Sky Survey quasi-stellar object (QSO) spectra. We used a sample of 341 DLA galaxies of mean redshift 〈z〉= 2.86 and log N(H i) ≥ 20.62 to place a 3σ upper limit of 3.0 × 10−18 erg s−1 cm−2 on the Lyα flux emitted within ∼1.5 arcsec (or 12 kpc) from the QSO line of sight. This corresponds to an average Lyα luminosity of ≤2 × 1041 erg s−1 or 0.03L★(Lyα). This limit is deeper than the limit of most surveys for faint Lyα emitters. The lack of Lyα emission in DLA galaxies is consistent with the in situ star formation, for a given N(H i), being less efficient than what is seen in local galaxies. Thus, the overall DLA population seems to originate from the low-luminosity end of the high-redshift Lyα-emitting galaxies and/or to be located far away from the star-forming regions. The latter may well be true since we detect strong O vi absorption in the stacked spectrum, indicating that DLA galaxies are associated with a highly ionized phase, possibly the relics of galactic winds and/or originating from cold accretion flows. We find the contribution of DLA galaxies to the global star formation rate density to be comparatively lower than that of Lyman break galaxies.
US Trends in Glycemic Control, Treatment, and Comorbidity Burden in Patients With Diabetes
Authors: Shaya Fadia T. , Yan Xia , Lin Pei‐Jung , Simoni‐Wastila Linda , Bron Morgan , Baran Robert , Donner Thomas W.
Published: October 2010

J Clin Hypertens (Greenwich). 2010;12:826‐832. © 2010 Wiley Periodicals, Inc.

This study explored trends over time in diabetes prevalence, glycemic control, and antidiabetic therapy choices among adults (18–64 years) and older adults (≥65 years). Factors that predict diabetes outcomes were explored. The study was cross‐sectional, with data from the 1999 to 2004 National Health and Nutrition Examination Survey. The study group consisted of 1211 persons with self‐reported diabetes. Other information obtained from the study included self‐reported medication for diabetes, hypertension, stroke, heart failure, and health status. The survey also provided examination or laboratory tests of obesity, nephropathy, and glycosylated hemoglobin level. Descriptive and logistic regression analyses were used in the study. The study showed that the proportion of diabetics with good glycemic control increased during the period from 1999 to 2004. However, nearly half of the adults and one third of older adults with diabetes did not reach glycemic control in 2003–2004. Overall, 59% of adults and 46% of older adults were obese. There was a high prevalence of hypertension, heart failure, stroke, and nephropathy among patients with diabetes, especially in older adults. The results indicate a high percentage of poor glycemic control among persons with diabetes. There were also a substantial number of comorbid conditions associated with diabetes.
River flood vulnerability in Norway through the pressure and release model
Authors: Rauken T. , Kelman I.
Published: October 2010

River floods in Norway have proven devastating for communities and individuals for centuries. Although usually incurring few flood fatalities, the Norwegian population is still vulnerable to river floods in that important infrastructure and other economic assets are located in flood zones. In trying to explain this vulnerability, this paper applies the Pressure and Release model. Two main root causes are identified: Norway's political and economic systems. The political system creates dynamic pressures in terms of governance issues permitting decision making that increases river flood vulnerability. The economic system creates a different dynamic pressure through the insurance system that leaves Norwegian municipalities with few economic incentives to leave flood zones undeveloped.
Post‐transcriptional regulation controlled by E‐cadherin is important for c‐Jun activity in melanoma
Authors: Spangler B. , Vardimon L. , Bosserhoff A. K. , Kuphal S.
Published: October 2010

A central event in the development of malignant melanoma is the loss of the tumor‐suppressor protein E‐cadherin. Here, we report that this loss is linked to the activation of the proto‐oncogene c‐Jun, a key player in tumorigenesis. In vivo, malignant melanomas show strong expression of the c‐Jun protein in contrast to melanocytes. Interestingly, c‐Jun mRNA levels did not differ in the melanoma cell lines when compared to melanocytes, suggesting that c‐Jun could be regulated at the post‐transcriptional level. To uncover the link between E‐cadherin and c‐Jun, we re‐expressed E‐cadherin in melanoma cells and detected decreased protein expression and activity of c‐Jun. Furthermore, c‐Jun accumulation is dependent on active E‐cadherin‐mediated cell–cell adhesion and regulated via the cytoskeleton. Additionally, we determined that, with respect to c‐Jun regulation, there are two melanoma subgroups. One subgroup regulates c‐Jun expression via the newly discovered E‐cadherin‐dependent signaling pathway, whereas the other subgroup uses the MAPKinases to regulate its expression. In summary, our data provide novel insights into the tumor‐suppressor function of E‐cadherin, which contributes to the suppression of c‐Jun protein translation and transcriptional activity independent of MAPKinases.
Perioperative optimization of oxygen delivery
Authors: CONTE BENJAMIN , L'HERMITE JOËL , RIPART JACQUES , LEFRANT JEAN‐YVES
Published: October 2010

The concept of perioperative hemodynamic optimization was developed by Shoemaker in the early 1980s. The controversy concerning optimization of oxygen delivery persists as recent studies show that the timing of this optimization appears to be an essential factor. At the initial stage of aggression (operative period, initial phase of septic shock), optimization of volume replacement decreases morbidity and mortality, while at a later period excess volume replacement can be harmful for the patient. The aim of this article is to review the physiological methods and indications for optimization of oxygen delivery.
Effect of Input Waveform Pattern and Large Blood Vessel Existence on Destruction of Liver Tumor Using Radiofrequency Ablation: Finite Element Analysis
Authors: Lim Dohyung , Namgung Bumseok , Woo Dae Gon , Choi Jin Seung , Kim Han Sung , Tack Gye Rae
Published: September 2010

Much research has been directed at improving the effectiveness of the radiofrequency (RF) ablation of hepatocellular carcinomas. In that point of view, this study was performed to provide comprehensive information of the relation between RF waveforms and thermodynamic response of the tissue with the consideration of four different types of RF waveforms (half-sine, half-square, half-exponential, and damped-sine) to maximize the amount of tumor tissue removed while maintaining the advantages of RF ablation. For the aim of this study, finite element models incorporating results from previous numerical models were used and validated with ex vivo experiments. From analyses of the entire results, we concluded that this study may prove valuable as a first step in providing comprehensive information of the relation between various RF waveforms and thermodynamic responses within the tissue during the RF ablation process. This study may also contribute toward studies to determine an optimum RF waveform capable of maximizing the amount of tumor tissue removed while maintaining the advantages of RF ablation.
Mass Transport in a Microchannel Bioreactor With a Porous Wall
Authors: Chen Xiao Bing , Sui Yi , Lee Heow Pueh , Bai Hui Xing , Yu Peng , Winoto S. H. , Low Hong Tong
Published: October 2010

A two-dimensional flow model has been developed to simulate mass transport in a microchannel bioreactor with a porous wall. A two-domain approach, based on the finite volume method, was implemented. For the fluid part, the governing equation used was the Navier–Stokes equation; for the porous medium region, the generalized Darcy–Brinkman–Forchheimer extended model was used. For the porous-fluid interface, a stress jump condition was enforced with a continuity of normal stress, and the mass interfacial conditions were continuities of mass and mass flux. Two parameters were defined to characterize the mass transports in the fluid and porous regions. The porous Damkohler number is the ratio of consumption to diffusion of the substrates in the porous medium. The fluid Damkohler number is the ratio of the substrate consumption in the porous medium to the substrate convection in the fluid region. The concentration results were found to be well correlated by the use of a reaction-convection distance parameter, which incorporated the effects of axial distance, substrate consumption, and convection. The reactor efficiency reduced with reaction-convection distance parameter because of reduced reaction (or flux), and smaller local effectiveness factor due to the lower concentration in Michaelis–Menten type reactions. The reactor was more effective, and hence, more efficient with the smaller porous Damkohler number. The generalized results could find applications for the design of bioreactors with a porous wall.
Quantifying Turbulent Wall Shear Stress in a Stenosed Pipe Using Large Eddy Simulation
Authors: Gårdhagen Roland , Lantz Jonas , Carlsson Fredrik , Karlsson Matts
Published: October 2010

Large eddy simulation was applied for flow of Re=2000 in a stenosed pipe in order to undertake a thorough investigation of the wall shear stress (WSS) in turbulent flow. A decomposition of the WSS into time averaged and fluctuating components is proposed. It was concluded that a scale resolving technique is required to completely describe the WSS pattern in a subject specific vessel model, since the poststenotic region was dominated by large axial and circumferential fluctuations. Three poststenotic regions of different WSS characteristics were identified. The recirculation zone was subject to a time averaged WSS in the retrograde direction and large fluctuations. After reattachment there was an antegrade shear and smaller fluctuations than in the recirculation zone. At the reattachment the fluctuations were the largest, but no direction dominated over time. Due to symmetry the circumferential time average was always zero. Thus, in a blood vessel, the axial fluctuations would affect endothelial cells in a stretched state, whereas the circumferential fluctuations would act in a relaxed direction.
Development of a Traumatic Anterior Cruciate Ligament and Meniscal Rupture Model With a Pilot In Vivo Study
Authors: Isaac Daniel I. , Meyer Eric G. , Haut Roger C.
Published: October 2010

The current study describes the development of a small animal, closed-joint model of traumatic anterior cruciate ligament (ACL) and meniscal rupture. This model can be used in future studies to investigate the roles of these acute damages on the long-term health of an injured knee joint. Forty-two Flemish Giant rabbits received an insult to the left tibiofemoral joint ex vivo in order to document optimal energy and joint orientation needed to generate ACL and meniscal rupture, without gross fracture of bone. Impact energies ranged from 10 J to 22 J, and joint flexion angle ranged from 60 deg to 90 deg. Three in vivo animals were impacted at 13 J with the knee flexed at 90 deg, as this was determined to be the optimal load and joint orientation for ACL and meniscal ruptures, and sacrificed at 12 weeks. Impact data from the ex vivo group revealed that 13 J of dropped-mass energy, generating approximately 1100 N of load on the knee, would cause ACL and meniscal ruptures, without gross bone fracture. Acute damage to the lateral and medial menisci was documented in numerous ex vivo specimens, with isolated lateral meniscal tears being more frequent than isolated medial tears in other cases. The in vivo animals showed no signs of ill health or other physical complications. At 12 week post-trauma these animals displayed marked degeneration of the traumatized joint including synovitis, cartilage erosion, and the formation of peripheral osteophytes. Histological microcracks at the calcified cartilage-subchondral bone interface were also evident in histological sections of these animals. A closed-joint model of traumatic ACL and meniscal rupture was produced, without gross bone fracture, and a pilot, in vivo study showed progressive joint degeneration without any other noticeable physical impairments of the animals over 12 weeks. This closed-joint, traumatic injury model may be useful in future experimental studies of joint disease and various intervention strategies.
Three-Dimensional Measurements of Photo-curing Process With Photo-curable Resin for UV-Nanoimprint by Micro-digital-Holographic-PTV
Authors: Satake Shin-ichi , Sorimachi Gaku , Kanai Takahiro , Taniguchi Jun , Unno Noriyuki
Published: October 2010

A high time-resolution measurement of flow field in a glass plate with glass cover with two holes was done by a micro-DHPTV system. The two holes mentioned here were also inside the photo-curable resin. Particle measurement was carried out during a 2 s time period that covered the time it took for the curing of resin. This curing time was theoretically calculated from the irradiation flux of the Ultraviolet (UV) source employed in the experiment. Moreover, temperature dependence of photo-curable resin was evaluated by measuring the resin at changing temperatures. Consequently, the tracking of seeding particles could instantaneously be recorded. The 3-D displacements, obtained from the particles being tracked, took place primarily along the direction of the depth. These values were found to be in good agreement with the theoretically calculated displacement values obtained from UV irradiation flux. Moreover, the displacement during photo-curing appeared to be proportional to the increase in temperature.
Using MicroCT Imaging Technique to Quantify Heat Generation Distribution Induced by Magnetic Nanoparticles for Cancer Treatments
Authors: Attaluri Anilchandra , Ma Ronghui , Zhu Liang
Published: October 2010

Magnetic nanoparticles have been used in clinical and animal studies to generate localized heating for tumor treatments when the particles are subject to an external alternating magnetic field. Currently, since most tissue is opaque, the detailed information of the nanoparticle spreading in the tissue after injections cannot be visualized directly and is often quantified by indirect methods, such as temperature measurements, to inversely determine the particle distribution. In this study, we use a high resolution microcomputed tomography (microCT) imaging system to investigate nanoparticle concentration distribution in a tissue-equivalent agarose gel. The local density variations induced by the nanoparticles in the vicinity of the injection site can be detected and analyzed by the microCT system. Heating experiments are performed to measure the initial temperature rise rate to determine the nanoparticle-induced volumetric heat generation rates (or specific absorption rate (SARW/m3)) at various gel locations. A linear relationship between the measured SARs and their corresponding microCT pixel index numbers is established. The results suggest that the microCT pixel index number can be used to represent the nanoparticle concentration in the media since the SAR is proportional to the local nanoparticle concentration. Experiments are also performed to study how the injection amount, gel concentration, and nanoparticle concentration in the nanofluid affect the nanoparticle spreading in the gel. The nanoparticle transport pattern in gels suggests that convection and diffusion are important mechanisms in particle transport in the gel. Although the particle spreading patterns in the gel may not be directly applied to real tissue, we believe that the current study lays the foundation to use microCT imaging systems to quantitatively study nanoparticle distribution in opaque tumor.
Analysis of Heat
Transfer in Consecutive Variable Cross-Sectional Domains: Applications in Biological Media and
Thermal Management
Authors: Mahjoob Shadi , Vafai Kambiz
Published: October 2010

Temperature prescription and control is important within biological media and in bioheat transport applications such as in hyperthermia cancer treatment in which the unhealthy tissue/organ is subject to an imposed heat flux. Thermal transport investigation and optimization is also important in designing heat management devices and small-scale porous-filled-channels utilized in electronic and biomedical applications. In this work, biological media or the stated heat management devices with a nonuniform geometry are modeled analytically as a combination of convergent, uniform and/or divergent configurations. The biological media is represented as blood saturated porous tissue matrix while incorporating cells and interstices. Two primary models, namely, adiabatic and constant temperature boundary conditions, are employed and the local thermal nonequilibrium and an imposed heat flux are fully accounted for in the presented analytical expressions. Fluid and solid temperature distributions and Nusselt number correlations are derived analytically for variable cross-sectional domain represented by convergent, divergent, and uniform or any combination thereof of these geometries while also incorporating internal heat generation in fluid and/or solid. Our results indicate that the geometrical variations have a substantial impact on the temperature field within the domain and on the surface with an imposed heat flux. It is illustrated that, the temperature distribution within a region of interest can be controlled by a proper design of the multisectional domain as well as proper selection of the porous matrix. These comprehensive analytical solutions are presented for the first time, to the best of the authors' knowledge in literature.
Adhesin-Specific Nanomechanical Cantilever Biosensors for Detection of Microorganisms
Authors: Tzeng Tzuen-Rong J. , Cheng Yunyan R. , Saeidpourazar Reza , Aphale Siddharth S. , Jalili Nader
Published: October 2010

Lectins (adhesins) on bacterial surfaces play important roles in infection by mediating bacterial adherence to host cell surfaces via their cognate receptors. We have explored the use of α-D-mannose receptors as capturing agents for the detection of Escherichia coli using a microcantilever and have demonstrated that E. coli ORN178, which expresses normal type-1 pili, can interact with microcantilevers functionalized with α-D-mannose and can cause shifts in its resonance frequencies. Although E. coli ORN208, which expresses abnormal pili, binds poorly to α-D-mannose on the nitrocellulose membrane of a FAST slide, it did cause a detectable shift in resonance frequency when interacting with the α-D-mannose functionalized microcantilevers.
Reliability Evaluation on Deterioration of Power Device Using Coupled Electrical-Thermal-Mechanical Analysis
Authors: Anzawa Takashi , Yu Qiang , Yamagiwa Masanori , Shibutani Tadahiro , Shiratori Masaki
Published: October 2010

This paper presents a simulation method to evaluate the thermal fatigue life of a power module. A coupled electrical-thermal analysis was performed to obtain the nonuniform temperature distribution of electric current. Then, a thermomechanical analysis was carried out based on the temperature distribution from the electrical-thermal analysis. Since crack propagation can change the route of heat transfer, a crack path simulation technique was used to investigate the fracture behavior of the power module. The crack initiates in the solder joint below the Al bonding wire of the insulated gate bipolar transistor module and propagates by increasing the diameter. The effect of the bonding type on power cycling fatigue life is also discussed. The fracture process was found to depend on the type of bonding. Lead frame bonding was found to be more effective than wire bonding.
Electron emission from silicon tip arrays controlled by np junction minority carrier injection
Authors: Young Robert M. , Nathanson Harvey C. , Howell Robert S. , Stewart Eric J. , Nechay Bettina A. , Braggins Timothy T. , Graves Eric M. , Van Campen Stephen D. , Clarke R. Christopher , Miserendino Scott B. , Hawk Jonathan
Published: October 2010

The authors demonstrate for the first time the injection of electrons across an n-type to p-type silicon junction and their subsequent tunneling from approximately 1 μm tall p-type silicon points into a vacuum gap. The diffusive flow of these minority carriers in the p-type material is controlled by the application of a bias voltage in the form of a base contact metallization contact on the p-type silicon, in analogy with a bipolar junction transistor. Using an array density of 4×106 tips/cm2, the authors measured a maximum average current of 1 nA per tip. Increasing the base contact bias voltage from 0 to ∼1 V changes the emission from a supply limited regime typically observed with p-type silicon emitters, bringing the emitted current back to a linear Fowler–Nordheim characteristic similar to that observed previously by photon generation of carriers in p-type silicon tips. The authors finally note that in our short tips, minority carrier flow should be a nondissipative largely adiabatic diffusive transport process which is followed by extraction into vacuum. A novel heat extraction mechanism for future cooling applications is thus anticipated.
The Calcium Store Sensor, STIM1, Reciprocally Controls Orai and Ca
V
1.2 Channels
Authors: Wang Youjun , Deng Xiaoxiang , Mancarella Salvatore , Hendron Eunan , Eguchi Satoru , Soboloff Jonathan , Tang Xiang D. , Gill Donald L.
Published: September 2010

Channel STIMulation

The STIM1 protein functions as a calcium sensor and regulates entry of calcium into cells across the plasma membrane. When cell surface receptors are stimulated and cause release of calcium from internal stores in the endoplasmic reticulum (ER), STIM proteins in the ER membrane interact with the Orai channel pore protein in the plasma membrane to allow calcium entry from the outside of the cell (see the Perspective by

Cahalan

).

Park
et al.

(p.
101
) and

Wang
et al.

(p.
105
) now show that STIM also acts to suppress conductance by another calcium channel—the voltage-operated Ca
V
1.2 channel. STIM1 appeared to interact directly with Ca
V
1.2 channels in multiple cell types, including vascular smooth muscle cells, neurons, and cultured cells derived from T lymphocytes. The interaction inhibited opening of the Ca
V
1.2 channels and caused depletion of the channel from the cell surface.
Multiple Exciton Collection in a Sensitized Photovoltaic System
Authors: Sambur Justin B. , Novet Thomas , Parkinson B. A.
Published: September 2010

Two for One

Solar cells often contain materials that absorb a broad spectrum of light above a certain frequency threshold, or band gap. Unfortunately, much of the energy contained in this light is wasted, because any balance exceeding the band gap tends to be dissipated as heat, rather than harnessed into electric current. Recent spectroscopic studies have shown that incident photons with energy several multiples of the band gap can transiently generate more than one current carrier, but the excess carriers tend to collapse before they can be diverted into the circuit.

Sambur
et al.

(p.
63
) now show that, when light-absorbing lead sulfide nanoparticles are carefully coupled to smoothly polished titanium dioxide crystalline electrodes, such excess carriers can be transferred into the circuit before collapsing.
Cenozoic L. A. Stories

Age of Mammals
John Harris, Curator

Natural History Museum of Los Angeles County, Los Angeles, CA. www.nhm.org/site/exploreexhibits/permanentexhibits/age-of-mammals
Authors: Pires Debra
Published: September 2010

A new hall at the Natural History Museum of Los Angeles County highlights the past 65 million years of mammalian evolution.
Polarized Myosin Produces Unequal-Size Daughters During Asymmetric Cell Division
Authors: Ou Guangshuo , Stuurman Nico , D’Ambrosio Michael , Vale Ronald D.
Published: October 2010

Daughter Diversity

Asymmetric cell division generates cell diversity and maintains tissue homeostasis. In early
Caenorhabditis elegans
embryos, the mitotic spindle is pulled toward one side of the cell by the molecular motor, dynein, and the cell divides into two unequally sized daughters. However, other types of asymmetric cell divisions (for example, in
Drosophila
neuroblasts) start with a centrally localized spindle. In this latter case, the mechanism by which two differently sized daughters are created is not understood.

Ou
et al.

(p.
677
, published online 30 September; see the Perspective by

Grill

) studied asymmetric cell divisions in the Q neuroblast lineage during
C. elegans
development and found that when the spindle was centred, myosin II accumulated at higher levels on the side of what will become the smaller daughter cell, giving rise to asymmetric myosin-based contractile forces acting on the membrane.
Apophysomyces elegans
: Epidemiology, Amplified Fragment Length Polymorphism Typing, and
In Vitro
Antifungal Susceptibility Pattern
Authors: Chakrabarti A. , Shivaprakash M. R. , Curfs-Breuker I. , Baghela A. , Klaassen C. H. , Meis J. F.
Published: September 2010

Apophysomyces elegans
is an emerging pathogen in India. We planned the present study to analyze the clinical pattern of the disease, to perform molecular strain typing, and to determine the
in vitro
activities of eight antifungal drugs against
A. elegans.
A total of 16 clinical and two environmental
A. elegans
isolates were included in the study. The clinical histories of the patients were noted. MICs or minimum effective concentrations (MECs) were determined for antifungal drugs by microdilution testing in accordance with CLSI standard M38-A2 guidelines. Of 16 patients, seven had rhino-cerebral, five had cutaneous, and three had renal zygomycosis. One patient had osteomyelitis. Uncontrolled diabetes was observed in 63% of the patients. Amplified fragment length polymorphism (AFLP) analysis divided the strains into two clearly different clades. The fingerprints of the environmental strains (including the type strain) were clearly different from those of the clinical strains. The MIC
50
s and MIC
90
s for amphotericin B, itraconazole, posaconazole, and isavuconazole were 2 and 4, 1 and 2, 0.5 and 1, and 2 and 4 μg/ml, respectively. The strains had high MICs for fluconazole, voriconazole, and echinocandins. The study indicates a possible change in the clinical pattern of zygomycosis due to
A. elegans
in India. The fungus caused not only cutaneous or subcutaneous infection but also other deep-seated infections, and the disease is commonly associated with uncontrolled diabetes. The AFLP patterns show a clear difference between environmental and clinical strains. Posaconazole is the most active drug against the isolates, followed by itraconazole. The MICs of amphotericin B against
A. elegans
were higher than those of the other drugs.
Reliability of the BD GeneOhm Methicillin-Resistant
Staphylococcus aureus
(MRSA) Assay in Detecting MRSA Isolates with a Variety of Genotypes from the United States and Taiwan
Authors: Boyle-Vavra Susan , Daum Robert S.
Published: September 2010

The BD GeneOhm methicillin-resistant
Staphylococcus aureus
(MRSA) assay is a molecular screening test for detection of MRSA in nasal colonization. This assay coamplifies the extremity of staphylococcal chromosome cassette
mec
(SCC
mec
) and adjacent chromosomal DNA at the SCC
mec
insertion site. Increasing reports of novel SCC
mec
types and the diverse genetic backgrounds of MRSA strains prompted us to test the accuracy of the BD GeneOhm MRSA kit with 914 MRSA isolates with a variety of SCC
mec
types harbored in 21 genetic backgrounds, as determined by the multilocus sequence type (ST). The BD GeneOhm MRSA assay was performed on colony lysates; purified genomic DNA (0.2 pg/μl and 0.2 ng/μl) was tested to confirm negative results from lysates. Of 914 MRSA isolates tested, 911 tested positive (detection rate, 99.7%). The SCC
mec
types carried by assay-positive isolates were I, II, III, IV, V, V
(5C2&5)
, VI, and VIII and SCC
mec
composite islands with
mec
class A and
ccr
complexes 2 and 4. One of the assay-negative isolates had a community-associated genotype: ST8, SCC
mec
type IV. However, this was an outlier among the 99.8% (434/435) ST8, SCC
mec
type IV-containing isolates that tested positive. The two other assay-negative isolates had a health care-associated genotype (ST5); both carried a distinct, uncommon, composite SCC
mec
type. In summary, the BD GeneOhm MRSA assay had a high rate of detection of MRSA isolates harboring common and uncommon SCC
mec
types from the United States and Taiwan.
Vaccination Reduces Simian-Human Immunodeficiency Virus Sequence Reversion through Enhanced Viral Control
Authors: Manuel Edwin R. , Yeh Wendy W. , Balachandran Harikrishnan , Clarke Ryon H. , Lifton Michelle A. , Letvin Norman L.
Published: September 2010

It has been suggested that vaccination prior to infection may direct the mutational evolution of human immunodeficiency virus type 1 (HIV-1) to a less fit virus, resulting in an attenuated course of disease. The present study was initiated to explore whether prior immunization might prevent the reversion of the virus to the wild-type form. Mamu-A*01 monkeys were vaccinated to generate a cytotoxic T-lymphocyte response to the immunodominant Gag p11C epitope and were then challenged with a cloned pathogenic CXCR4-tropic simian-human immunodeficiency virus (SHIV) expressing a mutant Gag p11C sequence (Δp11C SHIV). The epitopic and extraepitopic compensatory mutations introduced intogagof Δp11C SHIV resulted in attenuated replicative capacity and eventual reversions to the wild-type Gag p11C sequence in naïve rhesus monkeys. However, in vaccinated rhesus monkeys, no reversions of the challenge virus were observed, an effect that may have been a consequence of significantly decreased viral replication rather than a redirection of the mutational evolution of the virus. These findings highlight the multifactorial pressures that affect the evolution of primate immunodeficiency viruses.
CONFORMAL HOUSE
Authors: RYTTOV THOMAS A. , SANNINO FRANCESCO
Published: October 2010

We investigate the gauge dynamics of nonsupersymmetric SU (N) gauge theories featuring the simultaneous presence of fermionic matter transforming according to two distinct representations of the underlying gauge group. We bound the regions of flavors and colors which can yield a physical infrared fixed point. As a consistency check we recover the previously investigated bounds of the conformal windows when restricting to a single matter representation. The earlier conformal windows can be imagined to be part now of the new conformal house. We predict the nonperturbative anomalous dimensions at the infrared fixed points. We further investigate the effects of adding mass terms to the condensates on the conformal house chiral dynamics and construct the simplest instanton induced effective Lagrangian terms.
THE ROLE OF A CHAMELEON FIELD IN AN ANISOTROPIC UNIVERSE WITH LOGAMEDIATE AND INTERMEDIATE SCENARIOS
Authors: CHAKRABORTY SHUVENDU , DEBNATH UJJAL
Published: October 2010

In this work, we consider the Universe is being filled with matter composed of a chameleon-type dark energy scalar field. Employing a particular form of potential, we discuss the field's role in the accelerating phase of the Universe for an anisotropic model using the logamediate and intermediate forms of scale factors. The natures of statefinder and slow-roll parameters are discussed diagrammatically.
GRAVITATIONAL COUPLINGS OF HIGHER SPINS FROM STRING THEORY
Authors: POLYAKOV DIMITRI
Published: October 2010

We calculate the interaction 3-vertex of two massless spin-3 particles with a graviton using vertex operators for spin-3 fields in open string theory, constructed in our previous work. The massless spin-3 fields are shown to interact with the graviton through the linearized Weyl tensor, reproducing the result by Boulanger, Leclercq and Sundell. This is consistent with the general structure of the non-Abelian 2-s-s couplings, implying that the minimal number of space–time derivatives in the interaction vertices of two spin-s and one spin-2 particle is equal to 2s-2.
GENERALIZED BCS EQUATIONS: APPLICATIONS
Authors: MALIK G. P.
Published: October 2010

Based on the concepts of a superpropagator, multiple Debye temperatures, and equivalence of the binding energy of a Cooper pair and the BCS energy gap, the set of generalized BCS equations obtained recently via a temperature-generalized Bethe–Salpeter equation is employed for a unified study of the following composite superconductors: MgB2, Nb3Sn , and YBCO. In addition, we study the Nb – Al system in which Cooper pairs as resonances have recently been reported to have been observed. Our approach seems to suggest that a simple extension of the BCS theory that accommodates the concept of Cooper pairs bound via a more than one phonon exchange mechanism may be an interesting candidate for dealing with high-temperature superconductors.
PERIODIC WAVE SOLUTIONS FOR POCHHAMMER–CHREE EQUATION WITH FIVE ORDER NONLINEAR TERM AND THEIR RELATIONSHIP WITH SOLITARY WAVE SOLUTIONS
Authors: ZHANG WEIGUO , ZHAO YAN , LIU GANG , NING TONGKE
Published: October 2010

In this paper, periodic wave solutions for Pochhammer–Chree equation (PC-equation) with fifth order nonlinear term and their relationship with solitary wave solutions are studied. By designing innovative structure of solution, sixteen bounded periodic wave solutions in fractional form of Jacobi elliptic function (JEF) for PC-equation are given. Furthermore, global phase figure in the plane of the traveling solution for the PC-equation are obtained through dynamic systematic method, we indicate the region in the phase where the given sixteen solutions for PC-equation belong to. We find that two couples of these solutions change into two bell profile solitary wave solutions as k → 1 and four solutions change into four periodic wave solutions in fractional form of cosine function as k → 0. Finally, four figures are shown to describe the evolvement from periodic wave solutions to bell profile solitary wave solutions as k → 1.
ANISOTROPIC PRESSURE OF A QUANTUM GAS IN CONFINED SPACE
Authors: PANG HAI , DONG CHENG-WEI , QIU RONG-TAO , ZHANG YA-BIN
Published: September 2010

In confined space, the thermodynamic potential is shape-dependent. Therefore, the pressure of ideal gases in confined space is anisotropic. We study this anisotropy in a thermodynamic manner and find that the thermodynamic pressures usually depend on the form of deformations, and hence are not equal to each other which is a natural representation of the anisotropic mechanical properties of a confined ideal gas. We also find that the boundary effects are much more significant than the statistical fluctuations under low-temperature and high-density conditions. Finally, we show that there is little difference between the boundary effects in 2D space and those in 3D space.
DISTORTION IN FREE NILPOTENT GROUPS
Authors: DAVIS TARA C.
Published: September 2010

We prove that a subgroup of a finitely generated free nilpotent group F is undistorted if and only if it is a retract of a subgroup of finite index in F.
INTERACTING NON-MINIMALLY COUPLED CANONICAL, PHANTOM AND QUINTOM MODELS OF HOLOGRAPHIC DARK ENERGY IN NON-FLAT UNIVERSE
Authors: SETARE M. R. , ROZAS-FERNÁNDEZ ALBERTO
Published: September 2010

Motivated by our recent work,72 we generalize this work to the interacting non-flat case. Therefore in this paper we deal with canonical, phantom and quintom models, with various fields that are non-minimally coupled to gravity, within the framework of interacting holographic dark energy. We employ the holographic model of interacting dark energy to obtain the equation of state for the holographic energy density in non-flat (closed) universe enclosed by the event horizon measured from the sphere of horizon named L.
MICRO-DYNAMIC ASSOCIATED WITH TWO-STATE NONLINEAR MARKOV PROCESSES: WITH AN APPLICATION TO FREE RECALL
Authors: FRANK T. D. , RHODES T.
Published: October 2010

We examine the relationship between time-discrete nonlinear Markov processes defined in terms of nonlinear Markov chains and corresponding micro-dynamic models describing many-body systems composed of a finite number of units interacting with each other via a mean field. To this end, we consider a two-state model and examine appropriately defined measures for attractor strength and noise amplitude using variational calculus. We focus on a two-state model and demonstrate an application to free recall data from 8 participants.
RACIAL DIFFERENCES IN MLH1 AND MSH2 MUTATION: AN ANALYSIS OF YELLOW RACE AND WHITE RACE BASED ON THE INSIGHT DATABASE
Authors: WEI WENQIAN , LIU LEI , CHEN JIAN , JIN KE , JIANG FAN , LIU FANGQI , FAN RONG , CHENG ZHE , SHEN MENG , XUE CHENYI , CAI SANJUN , XU YE , NAN PENG
Published: September 2010

MLH1 and MSH2 mutations underlie 90% of hereditary nonpolyposis colorectal cancer (HNPCC) mutations. The International Society of Gastrointestinal Hereditary Tumors (InSiGHT) has established an international database of mutations associated with HNPCC. Based on the InSiGHT database and the original references that reported the mutations, we analyzed the distributions of MLH1 and MSH2 mutations in yellow race and white race respectively and compared them subsequently. We found: (1) the distributions of mutation individuals in exon 1, 17 and 19 of MLH1 gene and in exon 2 of MSH2 gene showed significant differences between the two race groups (p < 0.05); (2) the distributions of mutation types in exon 2, 7 and 18 of MLH1 and exon 10 and 16 of MSH2 showed significant differences (p < 0.05); and (3) three mutations (c.649C > T, c.1625A > T and c.1721T > C) in MLH1 and five mutations (c.23C > T, c.187dupG, c.505A > G, c.1168C > T and c.2211-6T > C) in MSH2 have much higher frequency in yellow race than those in white race. Furthermore, three mutations (c.1453G > C, c.1742C > T and c.1758dupC) in MLH1 and two mutations (c.1255C > A and c.1886A > G) in MSH2 were only found in yellow race, which implies that specific mutations in yellow race need more attention when screening mutations in these two genes.
A METHOD BASED ON LOCAL DENSITY AND RANDOM WALKS FOR COMPLEXES DETECTION IN PROTEIN INTERACTION NETWORKS
Authors: YU LIANG , GAO LIN , LI KUI
Published: September 2010

In this paper, we present a method based on local density and random walks (LDRW) for core-attachment complexes detection in protein-protein interaction (PPI) networks whether they are weighted or not. Our LDRW method consists of two stages. Firstly, it finds all the protein-complex cores based on local density of subnetwork. Then it uses random walks with restarts for finding the attachment proteins of each detected core to form complexes. We evaluate the effectiveness of our method using two different yeast PPI networks and validate the biological significance of the predicted protein complexes using known complexes in the Munich Information Center for Protein Sequence (MIPS) and Gene Ontology (GO) databases. We also perform a comprehensive comparison between our method and other existing methods. The results show that our method can find more protein complexes with high biological significance and obtains a significant improvement. Furthermore, our method is able to identify biologically significant overlapped protein complexes.
A SHORT NOTE ON FOURIER COEFFICIENTS OF HALF-INTEGRAL WEIGHT MODULAR FORMS
Authors: KOHNEN WINFRIED
Published: September 2010

We give an unconditional proof of a result on sign changes of Fourier coefficients of cusp forms of half-integral weight that before was proved only under the hypothesis of Chowla's conjecture.
QUADRATIC RECIPROCITY VIA RESULTANTS
Authors: HAMBLETON S. , SCHARASCHKIN V.
Published: September 2010

We give a simple inductive proof of quadratic reciprocity using resultants.
TUMOR SUPPRESSOR PATHWAYS AND CELLULAR ORIGINS OF BREAST CANCER: NEW COMPLEXITIES AND NEW HOPES
Authors: JOSEPH JERRY D. , GRINER NICHOLAS B. , TAO LUWEI
Published: September 2010

Heritable breast cancer syndromes have identified the recognition and processing of DNA double strand breaks as a fundamental vulnerability in the breast epithelium. The role of homology-directed DNA repair is particularly prominent, indicating that this repair pathway is rate-limiting. Although the activities of the tumor suppressor genes underlying heritable breast cancer act in a common pathway of DNA double strand break repair, the specific lesions result in surprisingly different patterns of biomarkers in the breast cancers, suggesting that they arise from different cell types that include the luminal, basal and progenitor cells within the breast epithelium. Therefore, each cell type appears to have distinct underlying vulnerabilities in repair of DNA double strand breaks. While the heterogeneity of targets poses a challenge to develop specific therapies, these pathways also render tumor cells sensitive to drugs targeting double strand break repair pathways offering new options for therapies. As double strand break repair is a common pathway underlying breast cancer risk, therapies that enhance the proficiency of this pathway offer a strategy for chemoprevention.
Obstacle discovery in distributed actuator and sensor networks
Authors: Zheng Rong , Vu Khuong , Pendharkar Amit , Song Gangbing
Published: October 2010

Distributed active sensing is a new sensing paradigm, where active sensors (aka actuators) as illuminating sources and passive sensors as receivers are distributed in a field, and collaboratively detect events of interest. In this paper, we study the fundamental properties of distributed actuator and sensor networks (DASNs) in detecting and localizing obstacles. A novel notion of “exposure” is defined, which quantifies the dimension limitations in detectability. Using simple geometric constructs, we propose polynomial-time algorithms to compute the exposure and bounding regions where the center of the obstacles may lie.
Approximation algorithms for computing minimum exposure paths in a sensor field
Authors: Djidjev Hristo N.
Published: October 2010

The exposure of a path
p
in a sensor field is a measure of the likelihood that an object traveling along
p
is detected by at least one sensor from a network of sensors, and is formally defined as an integral over all points
x
of
p
of the sensibility (the strength of the signal coming from
x
) times the element of path length. The minimum exposure path (MEP) problem is, given a pair of points
x
and
y
inside a sensor field, to find a path between
x
and
y
of minimum exposure. In this article we introduce the first rigorous treatment of the problem, designing an approximation algorithm for the MEP problem with guaranteed performance characteristics. Given a convex polygon
P
of size
n
with
O(n)
sensors inside it and any real number ϵ>0, our algorithm finds a path in
P
whose exposure is within an 1+ϵ factor of the exposure of the MEP, in time
O
(
n
/ϵ
2
ψlog
n
), where ψ is a geometric characteristic of the field. We also describe a framework for a faster implementation of our algorithm, which reduces the time by a factor of approximately θ(1/ϵ), while keeping the same approximation ratio.
In search of database consistency
Authors: Stonebraker Michael
Published: October 2010

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Communications
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Communications
, we'll publish selected posts or excerpts.

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Michael Stonebraker discusses the implications of the CAP theorem on database management system applications that span multiple processing sites.
Thinking clearly about performance, part 2
Authors: Millsap Cary
Published: October 2010

More important principles to keep in mind when designing high-performance software.
How offshoring affects IT workers
Authors: Tambe Prasanna B. , Hitt Lorin M.
Published: October 2010

IT jobs requiring interpersonal interaction or physical presence in fixed locations are less likely to be sent out of the country.
Peer-to-peer systems
Authors: Rodrigues Rodrigo , Druschel Peter
Published: October 2010

Within a decade, P2P has proven to be a technology that enables innovative new services and is used by millions of people every day.
Brains, not brawn
Authors: Morin Emmanuel , Daille Béatrice , Takeuchi Koichi , Kageura Kyo
Published: October 2010

Current research in text mining favors the quantity of texts over their representativeness. But for bilingual terminology mining, and for many language pairs, large comparable corpora are not available. More importantly, as terms are defined vis-à-vis a specific domain with a restricted register, it is expected that the representativeness rather than the quantity of the corpus matters more in terminology mining. Our hypothesis, therefore, is that the representativeness of the corpus is more important than the quantity and ensures the quality of the acquired terminological resources. This article tests this hypothesis on a French-Japanese bilingual term extraction task. To demonstrate how important the type of discourse is as a characteristic of the comparable corpora, we used a state-of-the-art multilingual terminology mining chain composed of two extraction programs, one in each language, and an alignment program. We evaluated the candidate translations using a reference list, and found that taking discourse type into account resulted in candidate translations of a better quality even when the corpus size was reduced by half.
Early development of intracellular calcium cycling defects in intact hearts of spontaneously hypertensive rats
Authors: Kapur Sunil , Aistrup Gary L. , Sharma Rohan , Kelly James E. , Arora Rishi , Zheng Jiabo , Veramasuneni Mitra , Kadish Alan H. , Balke C. William , Wasserstrom J. Andrew
Published: October 2010

Defects in excitation-contraction coupling have been reported in failing hearts, but little is known about the relationship between these defects and the development of heart failure (HF). We compared the early changes in intracellular Ca2+ cycling to those that underlie overt pump dysfunction and arrhythmogenesis found later in HF. Laser-scanning confocal microscopy was used to measure Ca2+ transients in myocytes of intact hearts in Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) at different ages. Early compensatory mechanisms include a positive inotropic effect in SHRs at 7.5–9 mo compared with 6 mo. Ca2+ transient duration increased at 9 mo in SHRs, indicating changes in Ca2+ reuptake during decompensation. Cell-to-cell variability in Ca2+ transient duration increased at 7.5 mo, decreased at 9 mo, and increased again at 22 mo (overt HF), indicating extensive intercellular variability in Ca2+ transient kinetics during disease progression. Vulnerability to intercellular concordant Ca2+ alternans increased at 9–22 mo in SHRs and was mirrored by a slowing in Ca2+ transient restitution, suggesting that repolarization alternans and the resulting repolarization gradients might promote reentrant arrhythmias early in disease development. Intercellular discordant and subcellular Ca2+ alternans increased as early as 7.5 mo in SHRs and may also promote arrhythmias during the compensated phase. The incidence of spontaneous and triggered Ca2+ waves was increased in SHRs at all ages, suggesting a higher likelihood of triggered arrhythmias in SHRs compared with WKY rats well before HF develops. Thus serious and progressive defects in Ca2+ cycling develop in SHRs long before symptoms of HF occur. Defective Ca2+ cycling develops early and affects a small number of myocytes, and this number grows with age and causes the transition from asymptomatic to overt HF. These defects may also underlie the progressive susceptibility to Ca2+ alternans and Ca2+ wave activity, thus increasing the propensity for arrhythmogenesis in HF.