bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Different Welded Structures on Mechanical Properties of TA2 Tube-to-Tubesheet Joints
Authors: Wei Xinlong , Qian Yang , Wang Junhui , Zhou Jianxin , Ling Xiang
Published: January 2014

Four types of TA2 welded tube-to-tubesheet joints prepared by manual tungsten arc argon-shielded welding technique are studied in this paper. The pull-out tests and low cycle fatigue tests were performed to optimize welded structures of tube and tubesheet. The results show that fractures of welded TA2 tube and tubesheet samples occur at weld zone of TA2 steel tube for the pull-out tests and low cycle fatigue tests. The extension-tubesheet welded joints have the maximum pull-out forces and the best fatigue resistance, and the internal-bore welded joint with 45 deg bevel occupies second place. Fractures are both initiated from weld toe of the outside of tube for the pull-out tests and low cycle fatigue tests. Crack propagates along the direction of 45 deg for the pull-out test. However, crack propagates perpendicularly to the direction of the applied load for low cycle fatigue test, and then fractures immediately parallel to the direction of the applied load. Fatigue striations with a spacing of about 10 μm can be observed on the fatigue crack propagation zone. However, hemispheroidal dimples exist on instant rupture zone.
Design of a Polyhedral Helix Curve Meshing Reducer
Authors: Chen Yangzhi , Ding Jiang , Lv Yueling
Published: January 2014

The space curve meshing wheel (SCMW) is an innovative gear mechanism based on the space curve meshing theory, and the helix curve meshing wheel (HCMW) is the most common SCMW. In this study, we propose the polyhedral helix curve meshing reducer (HCMR), which is based on the HCMW group. The installation dimension chains of the HCMW pairs are described for different included-angle cases and the HCMW group is produced by combining HCMW pairs. Finally, a polyhedral HCMR is designed with a single input shaft and multiple output shafts, with an adjustable gear box, for which a trial version was produced. The polyhedral HCMR has good application prospects because of its compact structure, high design flexibility, and low cost.
Dynamic Model of Variable Speed Process for Herringbone Gears Including Friction Calculated by Variable Friction Coefficient
Authors: Liu Changzhao , Qin Datong , Liao Yinghua
Published: January 2014

A dynamic model that includes friction and tooth profile error excitation for herringbone gears is proposed for the dynamic analysis of variable speed processes. In this model, the position of the contact line and relative sliding velocity are determined by the angular displacement of the gear pair. The translational and angular displacements are chosen as generalized coordinates to construct the dynamic model. The friction is calculated using a variable friction coefficient. The tooth profile error excitation is assumed to depend on the position along the contact line and to vary with the angular displacement of the driving gear. Thus, the proposed model can be used in the dynamic analysis of the variable speed process of a herringbone gear transmission system. An example acceleration process is numerically simulated using the model proposed in this paper. The dynamics responses are compared with those from the model utilizing a constant friction coefficient and without friction in cases where the profile error excitations are included and ignored.
Development of Boiling Water Reactor Steam Dryer Loading Evaluation Methods Through Scale Model Tests Under Actual Steam Conditions
Authors: Takahashi Shiro , Okuyama Keita , Tamura Akinori , Mabuchi Yasuhiro , Kubota Teppei , Yoshikawa Kazuhiro
Published: January 2014

Previous plant measurements and scale model tests have demonstrated that intense fluctuating pressure acted on the steam dryer in boiling water reactors (BWRs) at higher velocity flows than in normal operation. The cause of the dryer loading was considered as flow-induced acoustic resonance at the stub pipes of safety relief valves (SRVs) in the main steam lines (MSLs). Acoustic resonance was considered to be generated by the interaction between the sound field and the unstable shear layer across the opening of the side branches of the SRV stub pipes. Some air scale tests have been conducted and they are useful for evaluation of occurrence of acoustic resonance in SRV stub pipes and characteristics of fluctuating pressure in MSLs. However, it is possible that differences in pressure conditions and fluid properties may cause the dryer loading to be underestimated. In the present study, we conducted scale tests under actual steam conditions to evaluate the scale model test methods for BWR dryer loading estimation. The test apparatus consisted of a steam dryer, steam dome and 4 MSLs with 20 SRV stub pipes. We demonstrated that acoustic resonance occurred in the SRV stub pipes and the fluctuating pressure which propagated from the SRVs to the dryer caused fluctuating stress on the steam dryer at the SRV resonance frequency. Acoustic resonance started when Strouhal number decreased below 0.6 in both the scale model air and steam tests. The onset of resonance due to the single vortex mode was not influenced by pressure conditions and fluid properties. The increase of fluctuating pressure due to the double vortex mode which occurred at Strouhal number values from 0.8 to 0.9 could be clearly seen in the scale model steam tests unlike in the air tests. The results showed that the self-excited acoustic resonance was affected by the static pressure and fluid properties for the scale model air tests. However, no significant influence from steam pressure was seen at pressure higher than 3 MPa. Normalized fluctuating pressure was almost the same regardless of pressure. We verified that normalization by dynamic pressure in the main pipe was a reasonable approach for evaluation of fluctuating pressure in the SRV stub pipes. Increase of fluctuating pressure due to the double vortex mode was clearly distinguished in SRV stub pipes but not strong in the MSL pipes and had insignificant impact on the dryer loading.
Aeroacoustic Source Distribution in an Inline Tube Array With a Pitch Ratio of 3
Authors: Meskell Craig , Finnegan Shane L.
Published: January 2014

The flow induced acoustics in an inline tube bank (P/d = 3) subject to cross flow, indicative of a generic heat exchanger geometry, are examined over a range of flow velocities using particle image velocimetry (PIV) coupled with acoustic modal analysis using finite element analysis (FEA). The objective is twofold: to determine if the method originally developed for tandem cylinders is applicable to more geometrically complex configurations, with more restricted optical access; and hence to investigate the spatial distribution of acoustic sources within the tube array. The spatial and temporal aeroacoustic source distribution has been successfully obtained experimentally for the case of Strouhal acoustic coincidence (i.e., fa = fv). It is found that the acoustic sources are most intense behind the first row due to the spatial compactness of the vortices. However, a strong negative source (i.e., a sink) is also present in this location, so that the net contribution of the first row wake is small. In subsequent rows, the sources are weaker and more dispersed, but the sink is reduced dramatically. The result is that after the first row the remaining rows of the array contributes energy to the acoustic field. It is noted that, for the coincidence case in the tube bundle studied here, the spatial distribution of sources in the region around the first and second row is similar to the precoincidence regime found for tandem cylinders. This apparent contradiction requires further investigation. Nonetheless, it is concluded that the method of combining PIV with FEA to determine the source distribution can be applied to more complex geometries than previously reported.
Long-Period Pressure Pulsation Estimated in Numerical Simulations for Excessive Flow Rate Condition of Francis Turbine
Authors: Shingai Kenji , Okamoto Nobuaki , Tamura Yuta , Tani Kiyohito
Published: January 2014

A series of numerical simulations for a Francis turbine were carried out to estimate the unsteady motion of the cavity in the draft tube of the turbine under a much larger flow rate condition than the swirl-free flow rate. The evaporation and condensation process was described by using a simplified Rayleigh–Plesset equation. A two-phase homogeneous model was adopted to calculate the mixture of gas and liquid phases. Instantaneous pressure monitored at a point on the draft tube formed long-period pulsations. Detailed analysis of the simulation results clarified the occurrence of a uniquely shaped cavity and the corresponding flow pattern in every period of the pressure pulsations. The existence of a uniquely shaped cavity was verified with an experimental approach. A simulation without rotor-stator interaction also obtained long-period pulsations after an extremely long computational time. This result shows that the rotor-stator interaction does not contribute to the excitation of long-period pulsations.
Modeling Squeeze Films in the Vicinity of High Inertia Oscillating Microstructures
Authors: Diab Nadim A. , Lakkis Issam
Published: January 2014

This work investigates the effect of various assumptions proposed by the classical Reynolds lubrication equation. In particular, a microplate oscillating at high frequencies (beyond cutoff) and high velocities leading to appreciable displacement within the film gap is studied. An analytical model is derived with special emphasis on the fluid's inertia effect on the fluid/solid interface. By implementing the direct simulation Monte Carlo (DSMC) method, a numerical method for modeling rarefied gas flow, the analytically based model is adjusted for the force exerted by the gas on the oscillating micro-structure to capture various significant effects related to the fluid's inertia, compressibility, stiffness, and damping.
Probabilistic Solutions of Stochastic Oscillators Excited by Correlated External and Parametric White Noises
Authors: Guo Siu-Siu
Published: January 2014

The stationary probability density function (PDF) solution of random oscillators with correlated additive and multiplicative Gaussian excitations is investigated in this paper. The correlation between additive and multiplicative Gaussian excitations is taken into account. As a result, the generalized Fokker-Planck-Kolmogorov (FPK) equation is expressed with the independent part and the correlated part, which can be solved by the exponential-polynomial closure (EPC) method. The linear and nonlinear oscillators under correlated additive and multiplicative Gaussian white noise excitations are investigated. Two cases of different correlated additive and multiplicative excitations are considered. Compared with the results in the case of independent external and parametric excitations, unsymmetrical PDFs and nonzero means of system responses can be obtained.
Sulfur Effects on High-Temperature Creep and Fracture Behavior of 25Cr35Ni–Nb Alloys
Authors: Chen Tao , Chen Xuedong , Ye Juan
Published: January 2014

Centrifugal cast 25Cr35Ni–Nb alloy furnace tubes with different contents of S are selected to investigate effects of S addition on creep and fracture behavior. Rupture tests in air at 1100 °C and 17 MPa and slow rate tensile tests at 850 °C showed that the presence of S decreased the creep rupture life and elevated temperature ductility of 25Cr35Ni–Nb alloy obviously. Scanning electron micrographs (SEM) of the fracture and energy dispersive X-ray spectroscopy (EDS) analysis results indicated that S was the important element to control creep rupture life and elevated temperature ductility. S segregated to grain boundaries at elevated temperatures, and blocky fine sulfide particles with smooth surface distribute on the grain boundaries. The presence of sulfides became effective nucleation sites for intergranular creep cavities. Micro cracks occurred by linking up cavities at elevated temperatures due to local stress concentration. Eventually, early failure happened.
ROMO1 Is an Essential Redox-Dependent Regulator of Mitochondrial Dynamics
Authors: Norton Matthew , Ng Andy Cheuk-Him , Baird Stephen , Dumoulin Ariane , Shutt Timothy , Mah Nancy , Andrade-Navarro Miguel A. , McBride Heidi M. , Screaton Robert A.
Published: January 2014

ROMO1 links the oxidative state of the cell to changes in mitochondrial shape and function.
A Peptide Finds Its Receptor
Authors: Hines Pamela J.
Published: January 2014

A signaling system important in the regulation of plant cell size during development is identified.
New Chemical Scaffolds for Human African Trypanosomiasis Lead Discovery from a Screen of Tyrosine Kinase Inhibitor Drugs
Authors: Behera Ranjan , Thomas Sarah M. , Mensa-Wilmot Kojo
Published: January 2014

Human African trypanosomiasis (HAT) is caused by the protozoan
Trypanosoma brucei
. New drugs are needed to treat HAT because of undesirable side effects and difficulties in the administration of the antiquated drugs that are currently used. In human proliferative diseases, protein tyrosine kinase (PTK) inhibitors (PTKIs) have been developed into drugs (e.g., lapatinib and erlotinib) by optimization of a 4-anilinoquinazoline scaffold. Two sets of facts raise a possibility that drugs targeted against human PTKs could be “hits” for antitrypanosomal lead discoveries. First, trypanosome protein kinases bind some drugs, namely, lapatinib, CI-1033, and AEE788. Second, the pan-PTK inhibitor tyrphostin A47 blocks the endocytosis of transferrin and inhibits trypanosome replication. Following up on these concepts, we performed a focused screen of various PTKI drugs as possible antitrypanosomal hits. Lapatinib, CI-1033, erlotinib, axitinib, sunitinib, PKI-166, and AEE788 inhibited the replication of bloodstream
T. brucei
, with a 50% growth inhibitory concentration (GI
50
) between 1.3 μM and 2.5 μM. Imatinib had no effect (i.e., GI
50
> 10 μM). To discover leads among the drugs, a mouse model of HAT was used in a proof-of-concept study. Orally administered lapatinib reduced parasitemia, extended the survival of all treated mice, and cured the trypanosomal infection in 25% of the mice. CI-1033 and AEE788 reduced parasitemia and extended the survival of the infected mice. On the strength of these data and noting their oral bioavailabilities, we propose that the 4-anilinoquinazoline and pyrrolopyrimidine scaffolds of lapatinib, CI-1033, and AEE788 are worth optimizing against
T. brucei
in medicinal chemistry campaigns (i.e., scaffold repurposing) to discover new drugs against HAT.
Sensitive Deep-Sequencing-Based HIV-1 Genotyping Assay To Simultaneously Determine Susceptibility to Protease, Reverse Transcriptase, Integrase, and Maturation Inhibitors, as Well as HIV-1 Coreceptor Tropism
Authors: Gibson Richard M. , Meyer Ashley M. , Winner Dane , Archer John , Feyertag Felix , Ruiz-Mateos Ezequiel , Leal Manuel , Robertson David L. , Schmotzer Christine L. , Quiñones-Mateu Miguel E.
Published: January 2014

With 29 individual antiretroviral drugs available from six classes that are approved for the treatment of HIV-1 infection, a combination of different phenotypic and genotypic tests is currently needed to monitor HIV-infected individuals. In this study, we developed a novel HIV-1 genotypic assay based on deep sequencing (DeepGen HIV) to simultaneously assess HIV-1 susceptibilities to all drugs targeting the three viral enzymes and to predict HIV-1 coreceptor tropism. Patient-derivedgag-p2/NCp7/p1/p6/pol-PR/RT/IN- andenv-C2V3 PCR products were sequenced using the Ion Torrent Personal Genome Machine. Reads spanning the 3′ end of the Gag, protease (PR), reverse transcriptase (RT), integrase (IN), and V3 regions were extracted, truncated, translated, and assembled for genotype and HIV-1 coreceptor tropism determination. DeepGen HIV consistently detected both minority drug-resistant viruses and non-R5 HIV-1 variants from clinical specimens with viral loads of ≥1,000 copies/ml and from B and non-B subtypes. Additional mutations associated with resistance to PR, RT, and IN inhibitors, previously undetected by standard (Sanger) population sequencing, were reliably identified at frequencies as low as 1%. DeepGen HIV results correlated with phenotypic (original Trofile, 92%; enhanced-sensitivity Trofile assay [ESTA], 80%; TROCAI, 81%; and VeriTrop, 80%) and genotypic (population sequencing/Geno2Pheno with a 10% false-positive rate [FPR], 84%) HIV-1 tropism test results. DeepGen HIV (83%) and Trofile (85%) showed similar concordances with the clinical response following an 8-day course of maraviroc monotherapy (MCT). In summary, this novel all-inclusive HIV-1 genotypic and coreceptor tropism assay, based on deep sequencing of the PR, RT, IN, and V3 regions, permits simultaneous multiplex detection of low-level drug-resistant and/or non-R5 viruses in up to 96 clinical samples. This comprehensive test, the first of its class, will be instrumental in the development of new antiretroviral drugs and, more importantly, will aid in the treatment and management of HIV-infected individuals.
GAPO syndrome with pansutural craniosynostosis leading to intracranial hypertension
Authors: Goyal Nishant , Gurjar Hitesh , Sharma Bhawani Shankar , Tripathi Manjari , Chandra P Sarat
Published: January 2014

GAPO syndrome stands for growth retardation (G), alopecia (A), pseudoanodontia (P) and optic atrophy (O). To date, only about 35 cases of this extremely rare syndrome have been reported. Craniosynostosis/craniostenosis is a condition with an abnormal head shape due to premature fusion of the calvarial sutures and can be either non-syndromic or syndromic. Overall, craniosynostosis has an incidence of about 1 in 2500 live-births. We present a patient with GAPO syndrome in association with craniosynostosis along with intracranial hypertension, which was the cause of her headache. To the best of our knowledge, this is the first such association in the literature.
Cervical epidural abscess following anEscherichia coliurinary tract infection
Authors: O'Neill Shane C , Baker Joseph F , Ellanti Prasad , Synnott Keith
Published: January 2014

A previously healthy 64-year-old man developed anEscherichia colispinal epidural abscess (SEA) isolated to the cervical vertebrae posturinary tract infection 9 days previously. He subsequently underwent emergent surgical decompression followed by a prolonged course of intravenous antibiotics. He is symptom free at 1-year follow-up. SEA is an uncommon condition. Even with modern surgical techniques and antimicrobial agents, the mortality remains significant. Intravenous drug use, spinal procedures and medical conditions such as diabetes, Crohn's disease and chronic renal failure are all known risk factors for SEA and the majority of cases are associated with at least one of these risk factors. The case report highlights the importance of maintaining a high index of suspicion for this condition even in patients without established risk factors who present with red flag symptoms: back pain, fever and neurological deficit, as the consequences of a delayed diagnosis can be severe.
Pulmonary inflammatory myofibroblastic tumour after Hodgkin's lymphoma
Authors: Ilic Vesna , Dunet Vincent , Beck-Popovic Maja , Boubaker Ariane
Published: January 2014

Positron emission tomography (PET)/CT plays a major role in staging, assessing response to treatment and during follow-up of paediatric Hodgkin's lymphoma (HL). Owing to high sensitivity to detect viable tumoural tissue, negative PET/CT is highly predictive of survival. However,18F-FDG is not specific for malignant disease and may concentrate in numerous benign/inflammatory lesions that may cause ‘false-positive’ results and follow-up PET/CT studies should be interpreted with caution. We report a case of pulmonary inflammatory myofibroblastic tumour, which developed during follow-up in a young patient with complete remission of a stage IIB HL and was fully treated with surgical resection.
Population-based cohort study of warfarin-treated patients with atrial fibrillation: incidence of cardiovascular and bleeding outcomes
Authors: Gallagher Arlene M , van Staa Tjeerd P , Murray-Thomas Tarita , Schoof Nils , Clemens Andreas , Ackermann Diana , Bartels Dorothee B
Published: January 2014

Objectives

Atrial fibrillation (AF) is the most common cardiac rhythm disorder with a significant health burden. The aim of this study was to characterise patients with recently diagnosed AF and to estimate the rates of comorbidities and outcome events requiring hospitalisation in routine clinical practice.

Design

Pharmacoepidemiological cohort study using observational data.

Methods/setting

This study included 16 513 patients with a first diagnosis of AF between 1 January 2005 and 28 February 2010 (newly diagnosed patients) using data from the UK Clinical Practice Research Datalink (CPRD) linked to Hospital Episode Statistics (HES) and the Office for National Statistics mortality data. Exposure was stratified by vitamin K antagonist (VKA) exposure (non-use, current, recent and past exposure) based on prescriptions and/or international normalised ratio measurements, and followed for outcome events of interest based on diagnosis codes in the databases, that is, vascular outcomes, bleeding events and others. The main focus of the study was on outcome events requiring hospitalisation using the HES data.

Results

The incidence of vascular outcome hospitalisations (myocardial infarction (MI), stroke or systemic arterial peripheral embolism) was 3.8 (95% CI 3.5 to 4.0)/100 patient-years. The incidence of stroke was 0.9 (0.8 to 1.1) during current VKA exposure, 2.2 (1.6 to 2.9) for recent, 2.4 (1.9 to 2.9) for past and 3.4 (3.1 to 3.7) during non-use. MI incidence was 0.7 (0.6 to 0.9) for current VKA exposure, 0.7 (0.4 to 1.2) for recent, 1.1 (0.8 to 1.5) for past and 1.9 (1.7 to 2.1) during non-use. The incidence of bleeding event hospitalisations was 3.8 (3.4 to 4.2) for current VKA exposure, 4.5 (3.7 to 5.5) for recent, 2.7 (2.2 to 3.3) for past and 2.9 (2.6 to 3.2) during non-use; 38% of intracranial bleeds and 6% of gastrointestinal bleeds were fatal.

Conclusions

This population-based study from recent years provides a comprehensive characterisation of newly diagnosed patients with AF and incidence estimates of common outcomes with a focus on hospitalised events stratified by VKA exposure. This study will help to place future data on new oral anticoagulants into perspective.
Role of faecal occult bloods in the diagnosis of iron deficiency anaemia
Authors: Chowdhury A T M Dilshad , Longcroft-Wheaton Gaius , Davis Andrew , Massey David , Goggin Patrick
Published: January 2014

Objective

To determine whether faecal occult blood (FOB) testing in patients with iron deficiency anaemia (IDA) can predict the presence of gastrointestinal cancer.

Design

Cohort study.

Settings

Single secondary care hospital UK.

Patients

All individuals aged 20 years and older referred for the investigation for IDA.

Interventions

Data was collected from all the patients regarding haemoglobin (Hb), mean corpuscular volume, age, sex, symptomatology and medication. All patients had FOB tests using laboratory guaiac and haemocell methods, and then underwent gastroscopy and colonoscopy.

Main outcome measures

Accuracy, sensitivity and specificity of FOBs for identifying cancer in the upper or lower gastrointestinal tract.

Results

In total, 292 patients completed the study; 37 patients were diagnosed with carcinoma (colon 34, gastro-oesophageal 3). Using an optimal combination of lab guiaic and haemocell test resulted in just one colorectal cancer being missed, a sensitivity of 97%, specificity of 49% and negative predictive value of 99%. The test was less effective for upper gastrointestinal cancer, with 2/3 tumours missed by the tests.

Conclusions

Patients who have negative FOB tests are very unlikely to have a colorectal cancer, and the benefits to further colonic investigation is limited. This should be carefully considered in patients with significant comorbidities, where the risks of investigation may outweigh the benefits.
Quantifying the potential impact of measurement error in an investigation of autism spectrum disorder (ASD)
Authors: Heavner Karyn , Newschaffer Craig , Hertz-Picciotto Irva , Bennett Deborah , Burstyn Igor
Published: January 2014

The Early Autism Risk Longitudinal Investigation (EARLI), an ongoing study of a risk-enriched pregnancy cohort, examines genetic and environmental risk factors for autism spectrum disorders (ASDs). We simulated the potential effects of both measurement error (ME) in exposures and misclassification of ASD-related phenotype (assessed as Autism Observation Scale for Infants (AOSI) scores) on measures of association generated under this study design. We investigated the impact on the power to detect true associations with exposure and the false positive rate (FPR) for a non-causal correlate of exposure (X2, r=0.7) for continuous AOSI score (linear model) versus dichotomised AOSI (logistic regression) when the sample size (n), degree of ME in exposure, and strength of the expected (true) OR (eOR)) between exposure and AOSI varied. Exposure was a continuous variable in all linear models and dichotomised at one SD above the mean in logistic models. Simulations reveal complex patterns and suggest that: (1) There was attenuation of associations that increased with eOR and ME; (2) The FPR was considerable under many scenarios; and (3) The FPR has a complex dependence on the eOR, ME and model choice, but was greater for logistic models. The findings will stimulate work examining cost-effective strategies to reduce the impact of ME in realistic sample sizes and affirm the importance for EARLI of investment in biological samples that help precisely quantify a wide range of environmental exposures.
Anthropogenic and habitat correlates of hybridization between hatchery and wild brook trout
Authors: Harbicht Andrew B. , Alshamlih Mohammed , Wilson Chris C. , Fraser Dylan J.
Published: January 2014

Human activities are breaking down barriers to interpopulation hybridization with results that range from populations that resist introgression to populations at serious risk of genetic extinction, particularly between wild and hatchery fish because of the routine stocking of lakes and streams containing wild populations. We investigated whether specific human actions and (or) habitat characteristics were associated with the extent of hybridization between hatchery and wild brook trout (Salvelinus fontinalis) occupying lakes in Algonquin Park, Ontario, Canada. Hatchery and wild trout tended to hybridize more in lakes (i) supporting smaller populations (i.e., having lower pH and situated at higher elevations), (ii) stocked earlier in the season, and (iii) with greater exposure to other human activities (fishing). Our results highlight how particular human activities may interact with specific habitat conditions to elicit hybridization in wild populations. Hence, the use of readily available habitat and land use data may provide an economical means of anticipating hybridization or identifying indigenous populations with minimal introgression.
TRACE ELEMENT ANALYSIS OF AEROSOL SAMPLES USING PIXE TECHNIQUE
Authors: OSWAL MUMTAZ , KAUR RAJBIR , KUMAR A. , SINGH K. P. , KUMAR SUNIL , MOHANTY B. P. , KUMAR SANJIV
Published: January 2014

The present study was carried out with the aim to determine the level of 82Pb in the environment by analyzing the aerosol samples. In our experiment, the aerosol samples were collected from Chandigarh city which is also named as “The City Beautiful”. Particle induced X-ray emission (PIXE) technique developed at CCCM, Hyderabad has been used for the detection of trace elements in the aerosol samples
Semen Cassiae Attenuates Myocardial Ischemia and Reperfusion Injury in High-Fat Diet Streptozotocin-Induced Type 2 Diabetic Rats
Authors: Fu Feng , Tian Fei , Zhou Heping , Lv Weifeng , Tie Ru , Ji Lele , Li Rong , Shi Zhenwei , Yu Liming , Liang Xiangyan , Xing Wenjuan , Xing Jinliang , Yu Jun , Sun Lijun , Zhu Hailong , Zhang Haifeng
Published: January 2014

Obese patients with type 2 diabetes mellitus (T2DM), which is characterized by hyperglycemia, are liable to more severe myocardial infarction. Semen Cassiae is proven to reduce serum lipid levels. This study investigated whether the Semen Cassiae extract (SCE) reduces myocardial ischemia and reperfusion (MI/R) injury with or without diabetes and the underlying mechanisms. The high-fat diet-fed streptozotocin (HFD-STZ) rat model was created as a T2DM model. Normal and DM rats received SCE treatment orally (10 mg/kg/day) for one week. Subsequently these animals were subjected to MI/R. Compared with the normal animals, DM rats showed increased plasma total cholesterol (TC) and triacylglycerol (TG), and more severe MI/R injury and cardiac functional impairment. SCE treatment significantly reduced the plasma TC and TG, improved the instantaneous first derivation of left ventricle pressure and reduced infarct size, decreased plasma creatine kinase and lactate dehydrogenase levels, and apoptosis index at the end of reperfusion in diabetic rats. Moreover, SCE treatment increased the antiapoptotic protein Akt and ERK1/2 phosphorylation levels. Pretreatment with a PI3K inhibitor wortmannin or an ERK1/2 inhibitor PD98059 not only blocked Akt and ERK1/2 phosphorylation respectively, but also inhibited the cardioprotective effects of SCE. However, SCE treatment did not show any effects on the MI/R injury in the normal rats. Our data suggest that SCE effectively improves myocardial function and reduces MI/R-induced injury in diabetic but not normal animals, which is possibly attributed to the reduced TC/TG levels and the triggered cell survival signaling Akt and ERK1/2.
Withania somniferaAttenuates Acid Production, Acid Tolerance and Extra-Cellular Polysaccharide Formation ofStreptococcus mutansBiofilms
Authors: Pandit Santosh , Song Kwang-Yeob , Jeon Jae-Gyu
Published: January 2014

Withania somnifera (Ashwagandha) is a plant of the Solanaceae family. It has been widely used as a remedy for a variety of ailments in India and Nepal. The plant has also been used as a controlling agent for dental diseases. The aim of the present study was to evaluate the activity of the methanol extract of W. somnifera against the physiological ability of cariogenic biofilms and to identify the components of the extract. To determine the activity of the extract, assays for sucrose-dependent bacterial adherence, glycolytic acid production, acid tolerance, and extracellular polysaccharide formation were performed using Streptococcus mutans biofilms. The viability change of S. mutans biofilms cells was also determined. A phytochemical analysis of the extract was performed using TLC and LC/MS/MS. The extract showed inhibitory effects on sucrose-dependent bacterial adherence (≥ 100 μg/ml), glycolytic acid production (≥ 300 μg/ml), acid tolerance (≥ 300 μg/ml), and extracellular polysaccharide formation (≥ 300 μg/ml) of S. mutans biofilms. However, the extract did not alter the viability of S. mutans biofilms cells in all concentrations tested. Based on the phytochemical analysis, the activity of the extract may be related to the presence of alkaloids, anthrones, coumarines, anthraquinones, terpenoids, flavonoids, and steroid lactones (withanolide A, withaferin A, withanolide B, withanoside IV, and 12-deoxy withastramonolide). These data indicate that W. somnifera may be a potential agent for restraining the physiological ability of cariogenic biofilms.
Red Cabbage (Brassica oleraceaL.) Mediates Redox-Sensitive Amelioration of Dyslipidemia and Hepatic Injury Induced by Exogenous Cholesterol Administration
Authors: Al-Dosari Mohammed S.
Published: January 2014

The widely used culinary vegetable, red cabbage (Brassica oleracea L. Var. capitata f. rubra), of the Brassicaceae family contains biologically potent anthocyanins and a myriad of antioxidants. Previous studies have shown that the pharmacological effects of red cabbage in vivo are redox-sensitive. The present study explored whether red cabbage modulates various histopathological and biochemical parameters in rats administered with a cholesterol-rich diet (CRD). To this end, prolonged administration of a lyophilized-aqueous extract of red cabbage (250 and 500 mg/kg body weight) significantly blunted the imbalances in lipids, liver enzymes and renal osmolytes induced by the CRD. The effects of red cabbage were compared to simvastatin (30 mg/kg body weight) treated rats. Estimation of malondialdehyde and non-protein sulfhydryls revealed robust antioxidant properties of red cabbage. Histopathological analysis of livers from rats administered with red cabbage showed marked inhibition in inflammatory and necrotic changes triggered by CRD. Similarly, in vitro studies using a 2′,7′-Dichlorofluorescein-based assay showed that red cabbage conferred cytoprotective effects in cultured HepG2 cells. In conclusion, the present study discloses the potential therapeutic effects of red cabbage in dyslipidemia as well as hepatic injury, that is at least, partly mediated by its antioxidant properties.
THE STATIC STRING
Authors: GIARDINO SERGIO
Published: January 2014

In this paper, the quantum fluctuation of a rigid and static string is reported to be identical to a free quantum particle. Solutions similar to this static string have already been found in the semiclassical quantization of pulsating strings, and our results show that the semiclassical quantization of pulsating strings is, in some cases, a perturbation of static strings. We also interpret the energy of the static string as a lower bound for the pulsating string and speculate about a description of quantum mechanics in terms of semiclassical string theory.
BCS-BEC CROSSOVER WITHOUT APPEAL TO SCATTERING LENGTH THEORY
Authors: MALIK G. P.
Published: January 2014

BCS-BEC (an acronym formed from Bardeen, Cooper, Schrieffer and Bose–Einstein condensation) crossover physics has customarily been addressed in the framework of the scattering length theory (SLT), which requires regularization/renormalization of equations involving infinities. This paper gives a frame by frame picture, as it were, of the crossover scenario without appealing to SLT. While we believe that the intuitive approach followed here will make the subject accessible to a wider readership, we also show that it sheds light on a feature that has not been under the purview of the customary approach: the role of the hole–hole scatterings vis-à-vis the electron–electron scatterings as one goes from the BCS to the BEC end. More importantly, we show that there are critical values of the concentration (n)and the interaction parameter (λ) at which the condensation of Cooper pairs takes place; this is a finding in contrast with the view that such pairs are automatically condensed.
China's New Foreign Policy Team
Authors: GORE Lance L P
Published: January 2014

The new foreign policy team is more professional and with an Asian focus than its older counterpart. Although still fragmented, it may have stronger leadership and better coordination. This is critically important because China is at a defining moment as to its international role. Xi Jinping's closer ties with the military and his hands-on style may encourage assertive nationalism and more active role of the military in foreign affairs.
Xi Jinping's First Overseas Foray: Objectives, Outcomes and Implications
Authors: LYE Liang Fook
Published: January 2014

Xi made his first overseas state visits to Russia, Tanzania, South Africa and the Republic of Congo, and attended the fifth BRICS leaders' summit shortly after becoming China's president in March 2013. The visits show Xi's confident grip on power and China's emphasis on building ties with its giant neighbour and developing countries. To some extent, this is China's response to a US rebalance in the Asia-Pacific region that appears directed at China.
Formal and Informal Financial Channels in China
Authors: WANG Lihong
Published: January 2014

China has achieved remarkable growth despite weak legal protection of investors and an underdeveloped financial system. Other financing channels have played a significant role in the growth of the non-state sector. However, informal financial organisations do not have mechanisms that guard against financial risks and lack a reserve and deposit insurance system. Recent measures seem inadequate in accelerating the development of China's financial market. More and bolder reforms are needed.
China's Increasing Environmental Awareness and its Broad Implications
Authors: CHEN Gang
Published: January 2014

In most days of January 2013, many Chinese cities including Beijing and Shanghai were in an unprecedented smog crisis that saw air pollution indicators reaching hazardous and off-the-chart levels. The government was more tactful this time and reported candidly on the pollution. The new leaders played an important role in the data disclosure. The smog reinforces the government's resolve to de-emphasise GDP growth in its development strategy.
Chinese Democratisation: The Nature and Role of the Middle Class
Authors: HU Xiaobo
Published: January 2014

Rapid economic development and a rising middle class have given hope to China's political development. The democratisation history around the world provides clues to the possible directions China's new middle class might be heading in politics. The conservative Chinese middle class is predicted to make China's democratisation more stable than volatile, more gradual than radical. China may experience a long but steady path towards democratisation just like other major democratised countries.
The Clash of Nationalism Between China and Japan in the 21st Century
Authors: YANG Lijun
Published: January 2014

This article seeks to explain the sources of rising nationalism in China and Japan by focusing on the following questions: What is the main agenda of Chinese and Japanese nationalism? What is the main feature of Chinese and Japanese nationalism and how are they presented with respect to one another? What are the similarities and differences between Chinese and Japanese nationalism?
Anti-Poverty in China: Minimum Livelihood Guarantee Scheme
Authors: QIAN Jiwei
Published: January 2014

“Di Bao” or Minimum Livelihood Guarantee Scheme is a national means-tested programme to provide cash transfers to the poor based on a locally set minimum income level. In 2011, the outlay of “Di Bao” reached RMB134 billion and more than 70 million people were covered. Issues to be addressed for the “Di Bao” programme include low financial coverage, fragmented management, mistargeting as well as incentive compatibility of the scheme.
Post-Myitsone Relations Between China and Myanmar – More Continuity than Change?
Authors: COOK Alistair D B
Published: January 2014

While the world's media has centred on the opening up of Myanmar and the removal of sanctions by the West, less attention has been focused on Myanmar's relations with China. Can this relationship be ignored within the context of the Sino-American rivalry in the Asia-Pacific? This policy article focuses on the recent evolution of China-Myanmar relations and Chinese interests in and perceptions of Myanmar in transition.
Camera selection for tracking in distributed smart camera networks
Authors: Tessens Linda , Morbee Marleen , Aghajan Hamid , Philips Wilfried
Published: January 2014

Tracking persons with multiple cameras with overlapping fields of view instead of with one camera leads to more robust decisions. However, operating multiple cameras instead of one requires more processing power and communication bandwidth, which are limited resources in practical networks.

When the fields of view of different cameras overlap, not all cameras are equally needed for localizing a tracking target. When only a selected set of cameras do processing and transmit data to track the target, a substantial saving of resources is achieved. The recent introduction of smart cameras with on-board image processing and communication hardware makes such a distributed implementation of tracking feasible.

We present a novel framework for selecting cameras to track people in a distributed smart camera network that is based on generalized information-theory. By quantifying the contribution of one or more cameras to the tracking task, the limited network resources can be allocated appropriately, such that the best possible tracking performance is achieved.

With the proposed method, we dynamically assign a subset of all available cameras to each target and track it in difficult circumstances of occlusions and limited fields of view with the same accuracy as when using all cameras.
Adaptive instantiation of the protocol interference model in wireless networked sensing and control
Authors: Zhang Hongwei , Che Xin , Liu Xiaohui , Ju Xi
Published: January 2014

Interference model is the basis of MAC protocol design in wireless networked sensing and control, and it directly affects the efficiency and predictability of wireless messaging. To exploit the strengths of both the physical and the protocol interference models, we analyze how network traffic, link length, and wireless signal attenuation affect the optimal instantiation of the protocol model. We also identify the inherent trade-off between reliability and throughput in the model instantiation. Our analysis sheds light on the open problem of efficiently optimizing the protocol model instantiation. Based on the analytical results, we propose the physical-ratio-K (PRK) interference model as a reliability-oriented instantiation of the protocol model. Via analysis, simulation, and testbed-based measurement, we show that PRK-based scheduling achieves a network throughput very close to (e.g., 95%) what is enabled by physical-model-based scheduling while ensuring the required packet delivery reliability. The PRK model inherits both the high fidelity of the physical model and the locality of the protocol model, thus it is expected to be suitable for distributed protocol design. These findings shed new light on wireless interference models; they also suggest new approaches to MAC protocol design in the presence of uncertainties in network and environmental conditions as well as application QoS requirements.
Optimal nonuniform deployment of sensors for distributed detection in wireless sensor networks
Authors: Kapnadak Vibhav , Coyle Edward J.
Published: January 2014

We determine the optimal nonuniform spatial density of nodes in a single-hop Wireless Sensor Network (WSN) whose task is the distributed detection of a target within its sensing field. The optimization approach accounts for such factors as the Medium Access Control (MAC) protocol being used, the wireless channel's propagation characteristics, a randomized sleep/wake-up scheduling protocol, network coverage constraints, the energy consumed, the time to reach a decision, and the number of nodes in the network. The node density that minimizes the average Decision Error Probability (DEP) when a node at the center of the network serves as the Cluster Head (CH) is shown to be a function of the distance from this CH. The solution of this optimization problem and simulations demonstrate both the significant performance improvement provided by nonuniform spatial densities and the trade-offs that are possible amongst energy, network lifetime, detection performance, and time to reach a decision.
Maximum likelihood analysis of conflicting observations in social sensing
Authors: Wang Dong , Kaplan Lance , Abdelzaher Tarek F.
Published: January 2014

This article addresses the challenge of truth discovery from noisy social sensing data. The work is motivated by the emergence of social sensing as a data collection paradigm of growing interest, where humans perform sensory data collection tasks. Unlike the case with well-calibrated and well-tested infrastructure sensors, humans are less reliable, and the likelihood that participants' measurements are correct is often unknown a priori. Given a set of human participants of unknown trustworthiness together with their sensory measurements, we pose the question of whether one can use this information alone to determine, in an analytically founded manner, the probability that a given measurement is true. In our previous conference paper, we offered the first maximum likelihood solution to the aforesaid truth discovery problem forcorroborating observationsonly. In contrast, this article extends the conference paper and provides the first maximum likelihood solution to handle the cases where measurements from different participants may beconflicting. The article focuses on binary measurements. The approach is shown to outperform our previous work used for corroborating observations, the state-of-the-art fact-finding baselines, as well as simple heuristics such as majority voting.
Troubleshooting interactive complexity bugs in wireless sensor networks using data mining techniques
Authors: Khan Mohammad Maifi Hasan , Le Hieu Khac , Ahmadi Hossein , Abdelzaher Tarek F. , Han Jiawei
Published: January 2014

This article presents a tool for uncovering bugs due to interactive complexity in networked sensing applications. Such bugs are not localized to one component that is faulty, but rather result from complex and unexpected interactions between multiple often individually nonfaulty components. Moreover, the manifestations of these bugs are often not repeatable, making them particularly hard to find, as the particular sequence of events that invokes the bug may not be easy to reconstruct. Because of the distributed nature of failure scenarios, our tool looks for
sequences
of events that may be responsible for faulty behavior, as opposed to localized bugs such as a bad pointer in a module. We identified several challenges in applying discriminative sequence mining for root cause analysis when the system fails to perform as expected and presented our solutions to those challenges. We also present two alternative schemes, namely, two-stage mining and the progressive discriminative sequence mining to address the scalability challenge. An extensible framework is developed where a front-end collects runtime data logs of the system being debugged and an offline back-end uses frequent discriminative pattern mining to uncover likely causes of failure. We provided several case studies where we applied our tool successfully to troubleshoot the cause of the problem. We uncovered a kernel-level race condition bug in the LiteOS operating system and a protocol design bug in the directed diffusion protocol. We also presented a case study of debugging a multichannel MAC protocol that was found to exhibit corner cases of poor performance (worse than single-channel MAC). The tool helped to uncover event sequences that lead to a highly degraded mode of operation. Fixing the problem significantly improved the performance of the protocol. We also evaluated the extensions presented in this article. Finally, we provided a detailed analysis of tool overhead in terms of memory requirements and impact on the running application.
Coverage quality and smoothness criteria for online view selection in a multi-camera network
Authors: Mavrinac Aaron , Chen Xiang , Tan Yonghong
Published: January 2014

The problem of online selection of monocular view sequences for an arbitrary task in a calibrated multi-camera network is investigated. An objective function for the quality of a view sequence is derived from a novel task-oriented, model-based instantaneous coverage quality criterion and a criterion of the smoothness of view transitions over time. The former is quantified by a priori information about the camera system, environment, and task generally available in the target application class. The latter is derived from qualitative definitions of undesirable transition effects. A scalable online algorithm with robust suboptimal performance is presented based on this objective function. Experimental results demonstrate the performance of the method—and therefore the criteria—as well as its robustness to several identified sources of nonsmoothness.
Education, always
Authors: McGettrick Andrew
Published: January 2014

In a recent issue of
Communications
, ACM President Vinton Cerf gave an excellent account of what ACM is doing to help reform K--12 education (August 2013, p. 7).