bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Mutation and Genetic Background on Drug Resistance in Mycobacterium tuberculosis
Authors: Fenner Lukas , Egger Matthias , Bodmer Thomas , Altpeter Ekkehardt , Zwahlen Marcel , Jaton Katia , Pfyffer Gaby E. , Borrell Sonia , Dubuis Olivier , Bruderer Thomas , Siegrist Hans H. , Furrer Hansjakob , Calmy Alexandra , Fehr Jan , Stalder Jesica Mazza , Ninet Béatrice , Böttger Erik C. , Gagneux Sebastien ,   for the Swiss HIV Cohort Study and the Swiss Molecular Epidemiology of Tuberculosis Study Group
Published: April 2012

Bacterial factors may contribute to the global emergence and spread of drug-resistant tuberculosis (TB). Only a few studies have reported on the interactions between different bacterial factors. We studied drug-resistant
Mycobacterium tuberculosis
isolates from a nationwide study conducted from 2000 to 2008 in Switzerland. We determined quantitative drug resistance levels of first-line drugs by using Bactec MGIT-960 and drug resistance genotypes by sequencing the hot-spot regions of the relevant genes. We determined recent transmission by molecular methods and collected clinical data. Overall, we analyzed 158 isolates that were resistant to isoniazid, rifampin, or ethambutol, 48 (30.4%) of which were multidrug resistant. Among 154 isoniazid-resistant strains,
katG
mutations were associated with high-level and
inhA
promoter mutations with low-level drug resistance. Only
katG
(
S315T
) (65.6% of all isoniazid-resistant strains) and
inhA
promoter −15C/T (22.7%) were found in molecular clusters.
M. tuberculosis
lineage 2 (includes Beijing genotype) was associated with any drug resistance (adjusted odds ratio [OR], 3.0; 95% confidence interval [CI], 1.7 to 5.6;
P
< 0.0001). Lineage 1 was associated with
inhA
promoter −15C/T mutations (OR, 6.4; 95% CI, 2.0 to 20.7;
P
= 0.002). We found that the genetic strain background influences the level of isoniazid resistance conveyed by particular mutations (interaction tests of drug resistance mutations across all lineages;
P
< 0.0001). In conclusion,
M. tuberculosis
drug resistance mutations were associated with various levels of drug resistance and transmission, and
M. tuberculosis
lineages were associated with particular drug resistance-conferring mutations and phenotypic drug resistance. Our study also supports a role for epistatic interactions between different drug resistance mutations and strain genetic backgrounds in
M. tuberculosis
drug resistance.
LINKED ${\mathcal{PT}}$-SYMMETRY TO SUPERSYMMETRY IN A CLASS OF NON-HERMITIAN HAMILTONIANS
Authors: SHALABY ABOUZEID M.
Published: April 2012

We introduce and study a class of non-Hermitian Hamiltonians which have velocity dependent potentials. Since stability cannot be advocated directly from the classical potential, we show that the energy spectra are real and bounded from below which proves the stability of the spectra of all members in the class. We find that the introduced class of non-Hermitian Hamiltonians do have a corresponding superpartner class of non-Hermitian Hamiltonians. We were able to introduce supercharges which in conjunction with the corresponding super Hamiltonians constitute a closed super algebra. Among the introduced Hamiltonians, we show that non-[Formula: see text]-symmetric Hamiltonians can be transformed into their corresponding superpartner Hamiltonians via a specific canonical transformation while the [Formula: see text]-symmetric ones failed to be mapped to their corresponding superpartner Hamiltonians via the same canonical transformation. Since canonical transformations preserve the spectrum, we conclude that non-[Formula: see text]-symmetric Hamiltonians out of the introduced class of Hamiltonians have the same spectrum as the corresponding superpartner Hamiltonians and thus supersymmetry (Susy) is broken for such Hamiltonians. This kind of intertwining of [Formula: see text]-symmetry and Susy is new as all the so far discussed cases concentrate on Hamiltonians of broken [Formula: see text]-symmetry that have broken Susy too while we showed that Susy can be also broken for non-[Formula: see text]-symmetric and non-Hermitian Hamiltonians.
RECOGNITION OF THE FACE IMAGES WITH OCCLUSION AND EXPRESSION
Authors: SHERMINA J. , VASUDEVAN V.
Published: April 2012

Face recognition, a kind of biometric identification, researched in several fields such as computer vision, image processing, and pattern recognition is a natural and direct biometric method. Face Recognition Technology has diverse potential over applications in the fields of information security, law enforcement and surveillance, smart cards, access control and more. Face recognition is one of the diverse techniques used for identifying an individual. Generally the image variations because of the change in face identity are less than the variations among the images of the same face under different illumination and viewing angle. Illumination and pose are the two major challenges, among the several factors that influence face recognition. After pose and illumination, the main factors that affect the face recognition performance are occlusion and expression. So in order to overcome these issues, we proposed an efficient face recognition system based on partial occlusion and expression. The similar blocks in the face image are identified and occlusion can be recovered using the block matching technique. This is combined with expression normalized by calculating the Empherical Mode Decomposition feature. Finally, the face can be recognized by using the PCA. From the implementation result, it is evident that our proposed method based on the PCA technique recognizes the face images effectively.
WAVE PROPAGATION MODELING IN HIGHLY HETEROGENEOUS MEDIA BY A POLY-GRID CHEBYSHEV SPECTRAL ELEMENT METHOD
Authors: SERIANI GÉZA , SU CHANG
Published: April 2012

A wide range of applications requires the modeling of wave propagation phenomena in media with variable physical properties in the domain of interest, while highly accurate algorithms are needed to avoid unphysical effects. Spectral element methods (SEM), based on either a Chebyshev or a Legendre polynomial basis, have excellent properties of accuracy and flexibility in describing complex models, outperforming other techniques. In the standard SEM approach the computational domain is discretized by using very coarse meshes and constant-property elements, but in some cases the accuracy and the computational efficiency may be seriously reduced. For instance, a finely heterogeneous medium requires grid resolution down to the finest scales, leading to an extremely large problem dimension. In such problems the wavelength scale of interest is much larger but cannot be exploited in order to reduce the problem size. A poly-grid Chebyshev spectral element method (PG-CSEM) can overcome this limitation. In order to accurately deal with continuous variation in the properties, or even with small scale fluctuations, temporary auxiliary grids are introduced which avoid the need of using any finer global grid, and at the macroscopic level the wave field propagation is solved maintaining the SEM accuracy and computational efficiency.
SYNTHESIS AND CHARACTERIZATION OF NICKEL DOPED CdS NANOPARTICLES
Authors: RAO B. SRINIVASA , REDDY V. RAJAGOPAL , KUMAR B. RAJESH , RAO T. SUBBA
Published: April 2012

In the present work, conventional chemical co-precipitation method was employed for the preparation of Nickel (2, 4, 6, 8 and 10 at.% of Ni ) doped CdS nanoparticles. The crystallite size and lattice parameters for each sample are determined from X-ray diffraction (XRD) analysis. From XRD patterns the broadening of the diffraction peaks indicates the nanostructure nature of the samples. Surface morphology of the samples was studied by scanning electron microscope (SEM). UV-Visible absorption spectra for prepared samples are monitored for the optical properties of quantum sized particles. All nanoparticles formed lie in the size quantization regime and exhibit good crystallinity. Optical properties have been observed via UV-Vis spectroscopy and Photoluminescence spectra (PL) spectra. Ni doping in CdS is found to modify the luminescence properties by creating shallow acceptor states.
THE ROLE OF POTENTIAL FUNCTIONS IN THE MECHANICAL BEHAVIOR OF THE SINGLE WALL CARBON NANOTUBES
Authors: TALUKDAR KEKA , MITRA APURBA KRISHNA
Published: April 2012

Carbon nanotubes have been identified as the promising agents in reinforcing composite materials to achieve desired mechanical properties. In this study, three different types of single wall carbon nanotubes (SWCNTs) are subjected to molecular dynamics simulation to investigate their mechanical properties taking different interatomic potential functions. With unmodified Brenner's 2nd generation potential, a brittle fracture for all the SWCNTs is observed. But in tight-binding approach, the chiral and armchair SWCNTs exhibit somewhat extended plastic flow region before failure. With unmodified Brenner's potential, high tensile strength and ductility are observed for the armchair and chiral tubes. Y value of these two tubes is less than 1 TPa but more than 1 TPa for a zigzag tube. Much decrease of tensile strength and strain are noticed when we apply smoothing of the Brenner's potential at cut-off region. Failure stresses are dropped to much lower values for the three tubes. Ductility of the armchair and chiral tubes are also affected considerably by the choice of potential. Applying smoothing in the cut-off region to conserve the energy, the results show better agreement with the experimental findings.
Improving System Energy Efficiency with Memory Rank Subsetting
Authors: Ahn Jung Ho , Jouppi Norman P. , Kozyrakis Christos , Leverich Jacob , Schreiber Robert S.
Published: April 2012

VLSI process technology scaling has enabled dramatic improvements in the capacity and peak bandwidth of DRAM devices. However, current standard DDR
x
DIMM memory interfaces are not well tailored to achieve high energy efficiency and performance in modern chip-multiprocessor-based computer systems. Their suboptimal performance and energy inefficiency can have a significant impact on system-wide efficiency since much of the system power dissipation is due to memory power. New memory interfaces, better suited for future many-core systems, are needed. In response, there are recent proposals to enhance the energy efficiency of main-memory systems by dividing a memory rank into subsets, and making a subset rather than a whole rank serve a memory request.

We holistically assess the effectiveness of rank subsetting from system-wide performance, energy-efficiency, and reliability perspectives. We identify the impact of rank subsetting on memory power and processor performance analytically, compare two promising rank-subsetting proposals, Multicore DIMM and mini-rank, and verify our analysis by simulating a chip-multiprocessor system using multithreaded and consolidated workloads. We extend the design of Multicore DIMM for high-reliability systems and show that compared with conventional chipkill approaches, rank subsetting can lead to much higher system-level energy efficiency and performance at the cost of additional DRAM devices. This holistic assessment shows that rank subsetting offers compelling alternatives to existing processor-memory interfaces for future DDR systems.
Voluntary facial activations regulate physiological arousal and subjective experiences during virtual social stimulation
Authors: Vanhala Toni , Surakka Veikko , Courgeon Matthieu , Martin Jean-Claude
Published: April 2012

Exposure to distressing computer-generated stimuli and feedback of physiological changes during exposure have been effective in the treatment of anxiety disorders (e.g., social phobia). Here we studied voluntary facial activations as a method for regulating more spontaneous physiological changes during virtual social stimulation. Twenty-four participants with a low or high level of social anxiety activated either the
corrugator supercilii
(used in frowning) or the
zygomaticus major
(used in smiling) facial muscle to keep a female or a male computer character walking towards them. The more socially anxious participants had a higher level of skin conductance throughout the trials as compared to less anxious participants. Within both groups, short-term skin conductance responses were enhanced both during and after facial activations; and
corrugator supercilii
activations facilitated longer term electrodermal relaxation.
Zygomaticus major
activations had opposite effects on subjective emotional ratings of the less and the more socially anxious. In sum, voluntary facial activations were effective in regulating emotional arousal during virtual social exposure.
Corrugator supercilii
activation was found an especially promising method for facilitating autonomic relaxation.
Enhancing visuospatial map learning through action on cellphones
Authors: Ziat Mounia , Au Carmen , Abolhassani Amin Haji , Clark James J.
Published: April 2012

The visuospatial learning of a map on cellphone displays was examined. The spatial knowledge of human participants was assessed after they had learned the relative positions of London Underground stations on a map via passive, marginally active, or active exploration. Following learning, the participants were required to answer questions in relation to the spatial representation and distribution of the stations on the map. Performances were compared between conditions involving (1) without auditory cues versus continuous auditory cues; (2) without auditory cues versus noncontinuous auditory cues; and (3) continuous auditory cues versus noncontinuous auditory cues. Results showed that the participants perfomed better following active and marginally-active explorations, as compared to purely passive learning. These results also suggest that under specific conditions (i.e., continuous sound with extremely fast tempo) there is no benefit to spatial abilities from active exploration over passive observation; while continuous sound with moderate to fast tempo is effective for simple actions (i.e., key press).
Delay optimal event detection on ad hoc wireless sensor networks
Authors: Karumbu Premkumar , Prasanthi Venkata K. , Kumar Anurag
Published: April 2012

We consider a small extent sensor network for event detection, in which nodes periodically take samples and then contend over a
random access network
to transmit their measurement packets to the fusion center. We consider two procedures at the fusion center for processing the measurements. The Bayesian setting, is assumed, that is, the fusion center has a prior distribution on the change time. In the first procedure, the decision algorithm at the fusion center is
network--oblivious
and makes a decision only when a complete vector of measurements taken at a sampling instant is available. In the second procedure, the decision algorithm at the fusion center is
network--aware
and processes measurements as they arrive, but in a time-causal order. In this case, the decision statistic depends on the network delays, whereas in the network--oblivious case, the decision statistic does not. This yields a Bayesian change-detection problem with a trade-off between the random network delay and the decision delay that is, a higher sampling rate reduces the decision delay but increases the random access delay. Under periodic sampling, in the network--oblivious case, the structure of the optimal stopping rule is the same as that without the network, and the optimal change detection delay decouples into the network delay and the optimal decision delay without the network. In the network--aware case, the optimal stopping problem is analyzed as a partially observable Markov decision process, in which the states of the queues and delays in the network need to be maintained. A sufficient decision statistic is the network state and the posterior probability of change having occurred, given the measurements received and the state of the network. The optimal regimes are studied using simulation.
On the use of greedy shapers in real-time embedded systems
Authors: Wandeler Ernesto , Maxiaguine Alexander , Thiele Lothar
Published: April 2012

Traffic shaping is a well-known technique in the area of networking and is proven to reduce global buffer requirements and end-to-end delays in networked systems. Due to these properties, shapers also play an increasingly important role in the design of multiprocessor embedded systems that exhibit a considerable amount of on-chip traffic. Despite the growing importance of traffic shapping in this area, no methods exist for analyzing shapers in distributed embedded systems and for incorporating them into a system-level performance analysis. Until now it was not possible to determine the effect of shapers on end-to-end delay guarantees or buffer requirements in such systems. In this work, we present a method for analyzing greedy shapers, and we embed this analysis method into a well-established modular performance analysis framework for real-time embedded systems. The presented approach enables system-level performance analysis of complete systems with greedy shapers, and we prove its applicability by analyzing three case study systems.
Screening for Hypoglycemic Activity on the Leaf Extracts of Nine Medicinal Plants: In-Vivo Evaluation
Authors: Arya Aditya , Abdullah Mahmood Ameen , Haerian Batoul Sadat , Mohd Mustafa Ali
Published: April 2012

The traditional use of certain plants by the tribal community in central India involves using the young leaves for several ailments, including hyperglycaemia; this study was performed to evaluate the effects of the leaf extracts from 9 such plants in the management of diabetes. Initially, hypoglycemic screening was performed on normal rats whose blood glucose levels were measured before and after oral or intraperitoneal (i.p.) administration of the extracts at different periods. The plants were screened at doses of 250 mg/kg i.p. or 500 mg/kg orally. Of these, only Centratherum anthelminticum (Asteraceae), Cissus quadrangularis (Vitaceae), and Woodfordia fruticosa Kurz (Lythraceae) significantly reduced postprandial blood glucose levels in normal glycemic rats (P < 0.001), with slight reductions effected by Sida acuta Burm F. (P = 0.002) and Parthenium hysterophorus L. (P = 0.017). The extracts that reduced postprandial blood glucose levels both orally and i.p. in the hypoglycemic screening tests were evaluated for glucose challenge in glucose tolerance tests with i.p and oral administration in overnight‐fasted normal rats. The results of these tests potentiate the screening data in the management of diabetes mellitus, which requires further studies on the plants that yielded positive results to determine the active compounds in the different plant parts that are responsible for the activity.
Temperature Dependent Ultrasonic Study in Scandium Antimonide Semiconductor
Authors: Gupta A. K. , Srivastava S. , Thapa K. B.
Published: April 2012

In this paper analysis of wave propagation of elastic wave in scandium antimonide semiconductor was investigated. In scandium antimonide semiconductor, NaCl structure was found. Ultrasonic properties like ultrasonic attenuation, sound velocities, acoustic coupling constants, and thermal relaxation time have been investigated in cubic scandium antimonide semiconductor. Second and third order elastic constant have been computed for the evaluation of above said ultrasonic properties. Second and third elastic constant was studied at the various temperatures. Longitudinal and shear velocity was calculated by using the elastic constant. Longitudinal and shear velocity increase with increase the temperature. Ultrasonic attenuation either from longitudinal or shear wave propagation in cubic materials increase with increase the temperature.
Crescentic Glomerulonephritis with Anti-GBM and p-ANCA Antibodies
Authors: Javed Tariq , Vohra Parag
Published: April 2012

We are presenting a case of renal failure with anti-GBM and p-ANCA antibodies positive. Patients with dual antibodies are considered to be a vasculitis-variant of anti-GBM antibody nephritis. These patients may have atypical presentation and it may delay diagnosis and treatment. Recurrence rate is higher in these patients. We reviewed the literature of cases and studies on cresenteric glomerulonephritis with anti-GBM and p-ANCA positive patients. We recommend that patients suspected with pulmonary-renal syndrome should be checked for anti-GBM and p-ANCA antibodies, should undergo renal biopsy and should should have close long term follow up to watch for recurrence.
Synthesis and Antimicrobial Activity of 2‐[4‐(Substituted Benzylidenamino)‐5‐(Substituted Phenoxymethyl)‐4H‐1,2,4‐Triazol‐3‐yl thio] Acetic Acid Derivatives
Authors: Hunashal R. D. , Satyanarayana D. , Maddi V. S.
Published: April 2012

2‐[4‐(substituted benzylidenamino)‐5‐(substituted phenoxymethyl)‐4H‐1,2,4‐triazol‐3‐yl thio] acetic acid (3a‐j) derivatives have been synthesized by the reaction between 4‐(substituted benzylidenamino)‐5‐(substituted phenoxymethyl)‐2H‐1,2,4‐triazol‐3(4H)‐thiones (2a‐j) and chloroacetic acid containing catalytic amount of pyridine. All these compounds were screened for antimicrobial activity. The compounds 3h and 3j exhibited good antifungal activity against A. niger, C. Neoformans, and A. fumigatus at MIC of 0.25 μg/ml compared to standard drug fluconazole at MIC of 1 μg/mL.
Staminate Flower of Cocos Nucifera as Green Inhibitor for Mild Steel in HCl Medium
Authors: Rajalakshmi R. , Safina A. S.
Published: April 2012

Corrosion control methods, especially the use of inhibitors, have gained monumental importance in the present scenario of expunging corrosion and the quest for eco‐friendly reasons continues. To arrive at an inexpensive non‐toxic, eco‐friendly inhibitor formulations the present study on the use of Staminate Flower extract of Cocos Nucifera has been carried out by the classical weight loss measurements and electrochemical polarization measurements. The acid extract could bring out a maximum of 97.3% inhibition of mild steel corrosion in 1M HCl. Thermodynamic parameters of the corrosion process were calculated from temperature study. The adsorptive behaviour of Staminate Flower extract in acid solution may be approximated both by Langmuir and Temkin type isotherms. The results obtained by Tafel, Linear polarization resistance, and impedance spectroscopy have been correlated with the classical weight loss measurements. Values of Tafel constant ba and bc confirmed that the Staminate Flower extract acts like mixed type inhibitor. Examination of the surface of the metal in the presence of the inhibitor confirmed the deposition of inhibitor on the metal surface. The Staminate Flower extract in HCl medium efficiently inhibits the corrosion and proved to be zero cost inhibitor, eco‐friendly, non‐toxic, and highly economical.
Synthesis, Characterization and Antimicrobial Activity of Imidazole Derivatives Based on 2‐chloro‐7‐methyl‐3‐formylquinoline
Authors: Parab R. H. , Dixit B. C.
Published: April 2012

A series of oxazole and thereof imidazole derivatives were prepared from 2‐chloro‐7‐methyl‐3‐formyl quinoline. The structures of all synthesized compounds were elucidated by elemental, IR, 1HNMR, 13CNMR spectra. Supplementary to these, they were assayed in vitro for their antimicrobial activity; it was revealed that some synthesized derivatives were exhibiting competent biological activity against both gram negative and gram positive bacterial species and fungal microorganisms.
Determination of Benzalkonium Chloride in Nasal Drops by High‐Performance Liquid Chromatography
Authors: Kostić Danijela A. , Mitić Snezana S. , Nasković Danijela Č. , Zarubica Aleksandra R. , Mitic Milan N.
Published: April 2012

A high‐performance liquid chromatography (HPLC) system was used in the reversed phase mode for the determination of benzalkonium chloride (BKC) in nosal drops. A Chromolit RP‐18e, 100 x 4.6, (UM6077/035) column was used at 40 °C. The mobile phase, optimized through an experimental design, was a 70:30 (v/v) mixture of 0.057M Na‐heksansulphonate potassium, dihydrogen orthophosphate buffer (pH 2.9) and acetonitrile, pumped at a flow rate of 1.75 mL/min at maintaining column temperature at 40 °C. Maximum UV detection was achieved at 215 nm. The method was validated in terms of selectivity, linearity, repeatability, precision and accuracy. The method was successfully applied for the determination of BKC in a pharmaceutical formulation of nasal drop solution without any interference from common excipients and drug substance. All the validation parameters were within the acceptance range, concordant to ICH guidelines.
Microwave‐Assisted, One‐Pot Three Component Synthesis of 2‐Phenyl H‐imidazo[1,2‐α]pyridine
Authors: Motevalli Kourosh , Yaghoubi Zahra , Mirzazadeh Roghieh
Published: April 2012

A novel synthesis of 2‐phenylH‐imidazio[1,2‐α] pyridines is described from a one‐pot, three‐component reaction between pyridine, guanidine (urea or thiourea) and α‐bromoketones under microwave irradiation and solvent‐free conditions in excellent yields.
Development of Immunopathogenesis Strategies to Treat Behçet’s Disease
Authors: Köse Osman
Published: April 2012

Behçet disease is a chronic relapsing vasculitis with unclear etiology and immunopathogenesis. Antigenic stimuli, antigen presenting cells, T cells, monocyte, and neutrophil and endothelial cells are major parts of the pathology of the disease. Understanding of the new pathogenic mechanisms based on molecular structure of the disease helps us in improving the novel therapeutic modalities. These drugs target specific and nonspecific inhibition of the immun system. These therapies include biologic agents, new topical and systemic immunosuppressants, tolerizing agents, and immunoablation. Novel treatment will be promising to treat the especially recalcitrant cases to conventional therapy. In this paper, new aspect of the immunopathogenesis of Behçet’s diseases and novel treatment modalities will be discussed.
Use of Hg-Electroplated-Pt Ultramicroelectrode for Determining Elemental Sulphur in Naphtha Samples
Authors: de Andrade Carlos Eduardo , de Souza Flávia C. , Fernandes Daniella R. , Machado Sérgio A. S. , D'Elia Eliane
Published: April 2012

This paper describes the applicability of a Hg-electroplated-Pt ultramicroelectrode in the quantification of elemental sulphur in naphtha samples by square-wave voltammetry. A reproducible deposition methodology was studied and is reported in this paper. This methodology is innovative and relies on the quality of the mercury stock solution to obtain reproducible surfaces required for the analytical methodology. All analyses were performed using a Hg-electroplated-Pt ultramicroelectrode (Hg-Pt UME) due to the low sensibility of such devices to ohmic drops in resistive solutions. The responses of the peak areas in voltammetric experiments were linear in all of the range studied. The method developed here is accurate and reproducible, with a detection limit of 0.010 mg L−1and a good recovery range for both standard solutions of elemental sulphur (85 to 99%) and real naphtha sample (79%). These results attest to the potential for the application of this electroanalytical methodology in determining elemental sulphur in naphtha samples containing mercaptans and disulphides.
Pneumoperitoneum in a Micropremie: Not Always NEC
Authors: Khan Ahmed , de Waal Koert
Published: April 2012

Pneumoperitoneum in the newborn is an acute surgical emergency requiring immediate surgical intervention to ensure survival. It refers to radiological evidence of rupture of an air-containing viscus with resultant soiling of the peritoneal cavity. A female baby was born preterm at 29 weeks with birth weight of 650 grams. She developed abdominal distension on day 6, and abdominal radiography revealed presence of free air in the peritoneum. She proceeded for a laparotomy, and intraoperative findings revealed blood in the peritoneum with an area of inflammation and a small perforation. About 5 cm of the inflamed bowel was resected, and an end to end anastomosis performed. The histopathology of the specimen was consistent with Meckel's diverticulum. Symptomatic Meckel's diverticulum is usually seen in the first two years of life, and perforation is a rare presentation. Perforated Meckel's diverticulum in a premature newborn is very rare, and a review of literature reveals only one other reported case. Newborn Meckel's perforation cases often mimic necrotizing enterocolitis, although many present without any feature of peritonitis. Establishing a preoperative diagnosis of perforated Meckel's is difficult and may not be essential as the treatment remains the same. However, prompt surgical intervention confers a good prognosis in neonates with isolated perforated Meckel's diverticulum.
A Facile Solvent Free Synthesis of 3‐arylidenechroman‐4‐ones Using Grinding Technique
Authors: Kumar Suresh , Makrandi Jagdish K.
Published: April 2012

An efficient method for the synthesis of 3‐arylidenechroman‐4‐ones has been developed under solvent free conditions using grinding technique. Grinding of variously substituted chroman‐4‐ones with aromatic aldehydes in presence of anhydrous barium hydroxide at room temperature give 3‐arylidenechroman‐4‐ones in high yield (75‐92%). Products are obtained by just acidification of the reaction mixture in ice cold water. Reaction in solid state, with enhanced rate, high selectivity and manipulative simplicity are the attractive features of this environmentally benign protocol. The chroman‐4‐one derivatives required for the reaction have been obtained by polyphosphoric acid (PPA) catalysed cyclisation of phenoxypropanoic acids under microwave irradiations.
Determination of Capsaicin and Dihydrocapsaicin in Some Chilli Varieties using Accelerated Solvent Extraction Associated with Solid‐Phase Extraction Methods and RP‐HPLC‐Fluorescence
Authors: Chanthai Saksit , Juangsamoot Jureerat , Ruangviriyachai Chalerm , Techawongstien Suchila
Published: April 2012

Reversed phase‐HPLC with fluorescence detection of two major capsaicinoids was described. Isocratic elution using a ratio of methanol and deionized water (66:34, v/v) as mobile phase was used at a flow rate of 0.9 mL/min with well achieved separation within 6 min. Under optimum conditions, their analytical figures of merit for the HPLC method were validated. The linearity was in the range of 1.0‐25.0 μg/mL with multiple determination coefficients of higher than 0.995. The limit of detection was ranged of 0.008‐0.01 μg/mL. The repeatability and reproducibility of the retention time and peak area for these compounds were in good precision with their relative standard deviations (RSDs) lower than 1% and 5%, respectively. Both capsaicin and dihydrocapsaicin were extracted using an accelerated solvent extraction (ASE) of methanol as an extraction solvent for 5 min static time with 3 cycles. The methanolic extracts were subjected to clean up with C18 solid‐phase extraction (SPE) with its recoveries ranking of 90.2‐98.0%. The method recoveries of real samples were found to be 60.7‐98.6%. The optimized extraction method were applied for the determination of the two capsaicinoids in ten vareities of hot chilli pepper samples. Total contents of capsaicinoids were found in the range of 2,307.0‐9047.3 μg/g DW with their corresponding Scoville heat unit (SHU) of 34,600‐135,700. Additionally, the contents of capsaicinoids using external calibration method comparing with those of standard addition were not significantly different, indicating accuracy of the method. Mostly, the contents of capsaicin found in these real samples were rather higher than those of dihydrocapsaicin.
Synthesis and Characterization of a Novel Class of Lewis Acid Doped Tetraaniline
Authors: Basavaiah K. , Rao A. V. Prasada
Published: April 2012

Boron trifluoride (BF3) doped tetraaniline with novel structure were successfully synthesized via two step method. In the first step, emeraldine base form tetraaniline was synthesized via oxidative chemical polymerization of N‐phenyl‐1, 4‐phenylenediamine using ammonium persulphate as oxidant. In the second step involves control BF3 doping of tetraaniline using boron trifluoride etherate. As synthesized BF3 doped tetraaniline have been well characterized by UV‐Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction patterns (XRD), and scanning electron microscopy (SEM) and thermogravimetry. Thermogravimetry studies revealed that the BF3 doping improved the thermal stability of tetraaniline.
Comparison of Nondestructive Testing Methods on Detection of Delaminations in Composites
Authors: Cheng Liang , Tian Gui Yun
Published: April 2012

Delamination is one of the most common defects in carbon fibre reinforced plastic (CFRP) components, such as those used in aircraft and wind turbine blades. To detect delaminations, different NDT methods such as ultrasonic (UT), eddy current (EC) scanning, flash thermography, and recent developed pulsed-eddy-current-(PEC-) simulated thermography are conducted for comparison and evaluation of the new developed PEC thermography system at Nanjing University of Aeronautics and Astronautics (NUAA), China through UK-China collaboration. A PEC-stimulated thermography system is built at NUAA, extended from previous joint work between Newcastle and Bath Universities. Using these NDT systems, man-made, dedicated delaminations with varied diameters and depths are investigated and studied. Through this comparison, PEC-stumilated and flash thermography show relatively good indications of the shape of delaminations. The joint studies also show that PEC-stimulated thermography has unique advantage for fibre orientation evaluation.
Viscoelastic Flow through an Axisymmetric Contraction Using the Grid‐by‐Grid Inversion Method
Authors: Park H. M.
Published: April 2012

The newly developed algorithm called the grid‐by‐grid inversion method is a very convenient method for converting an existing computer code for Newtonian flow simulations to that for viscoelastic flow simulations. In this method, the hyperbolic constitutive equation is split such that the term for the convective transport of stress tensor is treated as a source which is updated iteratively. This allows the stress tensors at each grid point to be expressed in terms of velocity gradient tensor at the same location, and the set of stress tensor components is found after inverting a small matrix at each grid point. To corroborate the robustness and accuracy of the grid‐by‐grid inversion method, we apply it to the 4 : 1 axisymmetric contraction problem. This algorithm is found to be robust and yields accurate results as compared with other finite volume methods. Any commercial CFD packages for Newtonian flow simulations can be easily converted to those for viscoelastic fluids exploiting the grid‐by‐grid inversion method.
Optimizing a Hybrid Two‐Step Method for the Numerical Solution of the Schrödinger Equation and Related Problems with Respect to Phase‐Lag
Authors: Simos T. E.
Published: April 2012

We use a methodology of optimization of the efficiency of a hybrid two‐step
method for the numerical solution of the radial Schrödinger equation and related problems with
periodic or oscillating solutions. More specifically, we study how the vanishing of the phase‐lag
and its derivatives optimizes the efficiency of the hybrid two‐step method.
Evaluation of the White Test for the Intraoperative Detection of Bile Leakage
Authors: Leelawat Kawin , Chaiyabutr Kittipong , Subwongcharoen Somboon , Treepongkaruna Sa-ad
Published: April 2012

We assess whether the White test is better than the conventional bile leakage test for the intraoperative detection of bile leakage in hepatectomized patients. This study included 30 patients who received elective liver resection. Both the conventional bile leakage test (injecting an isotonic sodium chloride solution through the cystic duct) and the White test (injecting a fat emulsion solution through the cystic duct) were carried out in the same patients. The detection of bile leakage was compared between the conventional method and the White test. A bile leak was demonstrated in 8 patients (26.7%) by the conventional method and in 19 patients (63.3%) by the White test. In addition, the White test detected a significantly higher number of bile leakage sites compared with the conventional method (Wilcoxon signed-rank test; ). The White test is better than the conventional test for the intraoperative detection of bile leakage. Based on our study, we recommend that surgeons investigating bile leakage sites during liver resections should use the White test instead of the conventional bile leakage test.
Synthesis and Characterization of Salicylate Derivatives of Dibutyl Sn(IV)‐Ti(IV)‐μ‐Oxoisopropoxide
Authors: Kumar Rajesh
Published: April 2012

New Salicylate derivatives of organoheterobimetallic‐μ‐oxoisopropoxide [Bu2SnO2Ti2(OPri)6] have been synthesized by the thermal condensation of μ‐oxoisopropoxide compound with different salicylates in different molar ratios (1:1‐1:4) yielded the compounds of the type [Bu2SnO2Ti2(OPri)6-n(RSal)n] (where n is 1‐4 and RSal = Salicylate anion) respectively. The μ‐oxoisopropoxide derivative has been characterized by elemental, liberated isopropanol, and spectral analysis (IR, 1H, 13C, and 119Sn NMR).
1,3‐Dibromo 5,5‐dimethylhydantoin (DBH)‐Catalyzed Solvent‐Free Synthesis of 2‐arylbenzimidazoles under Microwave Irradiation
Authors: Forouzani Mehdi , Ghasemnejad-Bosra Hassan
Published: April 2012

An expeditious synthesis of 2‐aryl‐benzimidazoles by the condensation of o‐phenylenediamine with various arylaldehydes is described. This greener protocol is catalyzed by 1,3‐Dibromo 5,5‐dimethylhydantoin (DBH), and proceeds efficiently in the absence of any organic solvent under thermal condition and microwave irradiation in high yields.
Effects of Composition and Calcination Temperature on Photocatalytic Evolution over from Glycerol and Water Mixture
Authors: Fan Cancan , Wang Xitao , Sang Huanxin , Wang Fen
Published: April 2012

A series of sulfide coupled semiconductors supported on SiO2, (), was prepared by incipient wet impregnation method. The photocatalysts were characterized by XRD, XPS, TPR, and UV/Vis DRS. Characterization results show that the chemical actions between ZnS and CdS resulted in the formation of solid solutions on the surface of the support and the formation of them is affected by the molar ratio of ZnS/CdS and calcination temperature. Performance of photocatalysts was tested in the home made reactor under both UV light and solar-simulated light irradiation by detecting the rate of the photocatalytic H2evolution from glycerol solution. The hydrogen production rates are related to the catalyst composition, surface structure, photoabsorption property, as well as the amount of solid solution. The maximum rate of hydrogen production, 550 μmol·h−1under UV light irradiation and 210 μmol·h−1under solar-simulated light irradiation, was obtained over Cd0.8Zn0.2S/SiO2solid solution calcined at 723 K.
Synthesis of High‐Quality Carbon Nanotube Arrays without the Assistance of Water
Authors: Luo Yongfeng , Wang Xinjun , He Mengdong , Li Xi , Chen Hong
Published: April 2012

Long and high‐quality carbon nanotube (CNT) arrays have been synthesized through a chemical vapor deposition process. The Fe/Al2O3 on silicon was used as the catalyst, ethylene as the carbon source, and a gas mixture of Ar and H2 gases as the carrying gas. It is found for the first time that the high‐quality and superlong carbon nanotube array can be improved by varying the content of hydrogen and carbon source.
Propofol-Remifentanil Combination for Management of Electroconvulsive Therapy in a Patient with Neuroleptic Malignant Syndrome
Authors: Arasteh Modabber , Shami Shoaleh , Nasseri Karim
Published: April 2012

Electroconvulsive therapy can be effective in severe or treatment resistant neuroleptic malignant syndrome patients. Anesthesia and use of muscle relaxant agents for electroconvulsive therapy in such patients may encounter anesthesiologists with specific challenges. This case report describes successful management of anesthesia in 28-year-old male patient undergoing eight electroconvulsive therapy sessions for treatment of neuroleptic malignant syndrome.
Synthesis, Spectral and Antimicrobial Studies of Some Co(II), Ni(II) and Cu(II) Complexes Containing 2‐Thiophenecarboxaldehyde Moiety
Authors: Mishra A. P. , Tiwari A. , Gupta S. K. , Jain Rajendra
Published: April 2012

Some new Schiff base metal complexes of Co(II), Ni(II) and Cu(II) derived from 3‐chloro‐4‐fluoroaniline (HL1) and 4‐fluoroaniline (HL2) with 2‐thiophenecarboxaldehyde have been synthesized and characterized by elemental analysis, FT‐IR, FAB‐mass, molar conductance, electronic spectra, ESR and magnetic susceptibility. The complexes exhibit coordination number 4 or 6. The complexes are colored and stable in air. Analytical data revealed that all the complexes exhibited 1:2 (metal: ligand) ratio. FAB‐mass data show degradation pattern of the complexes. The Schiff base and metal complexes show a good activity against the bacteria; B. subtilis, E. coli and S. aureus and fungi A. niger, A. flavus and C. albicans. The antimicrobial results also indicate that the metal complexes are better antimicrobial agents as compared to the Schiff bases.
Platinum(II) Complexes with Tetradentate Schiff Bases as Ligands: Synthesis, Characterization and Detection of DNA Interaction by Differential Pulse Voltammetry
Authors: Li Lijun , Tian Chao , Wang Cheng , Wang Guangyuan , Wang Lianzeng , Du Jianlong
Published: April 2012

Five sterically hindered platinum(II) complexes with tetradentate schiff bases as ligands, [Pt(L)] (L= N,N′‐bisalicylidene‐1,2‐ethylenediamine (L1), N,N′‐bisalicylidene‐1,2‐cyclohexanediamine (L2), N,N′‐bis(5‐hydroxyl‐salicylidene)‐1,2‐cyclohexanediamine (L3), N,N′‐bisalicylidene‐1,2‐diphenyl‐ethylenediamine (L4) and N,N′‐bis(3‐tert‐butyl‐5‐methyl‐salicylidene)‐1,2‐diphenylethylenediamine (L5) ) have been synthesized and characterized by IR spectroscopy and elemental analysis. The sterical hindrance of antitumor drug candidates potentially makes them less susceptible to deactivation by sulphur containing proteins and helping to overcome resistance mechanisms. The interaction of these metal complexes with fish sperm single‐stranded DNA (ssDNA) was studied electrochemically based on the oxidation signals of guanine and adenine. Differential pulse voltammetry was employed to monitor the DNA interaction in solution by using renewable pencil graphite electrode. The results indicate that ligands with different groups can strongly affect the interaction between [Pt(L)] complexes and ssDNA due to sterical hindrances and complex [Pt(L1)] has the best interaction with DNA among the five complexes.
Ocular Symptomatology, Management, and Clinical Outcome of a Giant Intracranial Aneurysm
Authors: Terzidou Chryssa , Dalianis Georgios , Zacharaki Fani
Published: April 2012

Giant aneurysms of the anterior intracranial circulation are rare, slowly progressive vascular abnormalities, often presenting with neuro-ophthalmological symptoms before they rupture. This is a case of a 55-year-old woman with a double aneurysm of the anterior intracranial circulation, part of which was giant, diagnosed exclusively on the basis of ocular manifestations. We also describe successful management of the case throughout a long follow-up period.
Mounier-Kuhn Syndrome: Anesthetic Experience
Authors: Ushakumari Deepu Sasikumaran , Grewal Navneet , Green Michael
Published: April 2012

Mounier Kuhn syndrome, or congenital tracheobronchomegaly, is an under diagnosed clinical entity with peculiar anatomical and physiological features making anesthetic care challenging. A 58-year-old chronic smoker with history of recurrent pneumonia and bronchiectasis presented for septoplasty. Thoracic imaging revealed a dilated trachea and main bronchi, tracheal and bronchial diverticuli, and chronic bronchiectasis with mediastinal lymphadenopathy. An 8.5 cuffed endotracheal tube (ETT) proved too big for his glottic aperture. An 8.0 cuffed ETT with wet gauze packing yielding an adequate seal. Postoperative continuous positive airway pressure to prevent airway collapse followed awake extubation. Anesthetic concerns include grossly enlarged and weakened airways, inefficient cough mechanisms, presence of tracheal diverticuli, and post operative tracheal collapse. Anesthetic planning includes management of endotracheal cuff size. Small size yields air leak and ineffective ventilation. Large size may lead to mucosal damage. Tube dislodgement, copious secretions, chance of expiratory collapse due to the abnormally dilated and thin airways, and post operative monitoring all must be considered.
Study of Molecular Interactions in Binary Liquid Mixtures by Acoustical Method at 303K
Authors: Divakar P. Paul , Rao B. V. , Samatha K.
Published: April 2012

Ultrasonic velocity and density measurements were made in two binary liquid mixtures Isopropyl acetate (IPA) and Isobutyl acetate (IBA) with cyclohexanone (CY) as a common component at 303K, at fixed frequency of 2MHz using single crystal variable path interferometer and specific gravity bottle respectively. The experimental data have been used to calculate the acoustic impedance, adiabatic compressibility, inter molecular free length and molar volume. The excess thermodynamic parameters have been evaluated and discussed in the light of molecular interactions.
Regulation of Hepatic Paraoxonase-1 Expression
Authors: Fuhrman Bianca
Published: April 2012

Serum paraoxonase-1 (PON1) is a member of the paraoxonases family (PON1, PON2, and PON3). PON1 is synthesized and secreted by the liver, and in circulation it is associated with HDL. PON1 has antioxidative properties, which are associated with the enzyme’s capability to decrease oxidative stress in atherosclerotic lesions and to attenuate atherosclerosis development. Epidemiological evidence demonstrates that low PON1 activity is associated with increased risk of cardiovascular events and cardiovascular disease and is an independent risk factor for coronary artery disease. Therefore, pharmacological modulation of PON1 activity or PON1 gene expression could constitute a useful approach for preventing atherosclerosis. A primary determinant of serum PON1 levels is the availability of the enzyme for release by the liver, the principal site of PON1 production. Together with the enzyme secretion rate, enzymatic turnover, and protein stability, the level of PON1 gene expression is a major determinant of PON1 status. This paper summarizes recent progress in understanding the regulation of PON1 expression in hepatocytes.
Ain’t No Sunshine When She’s Gone: Pseudohypoparathyroidism Discovered in an Adult
Authors: van Rooijen C. R. , Kok M. B. , Simsek S. , Stam F.
Published: April 2012

An 18-year-old negroid woman presented with progressive cramps in both hands. She was Jamaican and had moved to The Netherlands 8 months before. On physical examination Trousseau’s sign was positive. Laboratory analysis showed severe hypocalcaemia (1.17 mmol/L) and hyperphosphatemia (2.0 mmol/L). Urinary excretion of both calcium (0.8 mmol/day) and phosphate (5 mmol/day) was low, as is seen in hypoparathyroidism. However, the PTH level was increased (22.1 pmol/L), whereas 25-(OH)-vitamin D was low (31 nmol/L). An Ellsworth-Howard test showed only a fivefold increase in urinary phosphate excretion after administration of synthetic PTH, supporting the diagnosis pseudohypoparathyroidism. Upon treatment with calcium supplementation and alfacalcidol, her symptoms disappeared. Pseudohypoparathyroidism (PHP) is a rare hereditary disorder resembling hypoparathyroidism, although plasma PTH levels are elevated. PHP is caused by alterations in the PTH receptor, inducing target tissue resistance to PTH. This results in hypocalcaemia and hyperphosphatemia, while PTH levels are elevated. The diagnosis is confirmed by the Ellsworth-Howard test, which will show a 100-fold increase in phosphate excretion if the PTH receptor functions properly. Treatment is lifelong supplementation of calcium and alfacalcidol. In our patient, symptoms were probably evoked by the lack of sunlight in Dutch winter, decreasing vitamin D levels and thereby aggravating hypocalcaemia.