bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing frequency of gram‐positive cocci and gram‐negative multidrug‐resistant bacteria in spontaneous bacterial peritonitis
Authors: Alexopoulou Alexandra , Papadopoulos Nikolaos , Eliopoulos Dimitrios G. , Alexaki Apostolia , Tsiriga Athanasia , Toutouza Marina , Pectasides Dimitrios
Published: March 2013

Background

Spontaneous bacterial peritonitis (SBP) is historically caused by Gram‐negative bacteria (GNB) almost exclusively Enterobacteriaceae. Recently, an increasing rate of infections with Gram‐positive cocci (GPC) and multidrug‐resistant (MDR) microorganisms was demonstrated.

Aims

To assess possible recent changes of the bacteria causing SBP in cirrhotic patients.

Methods

We retrospectively recorded 47 cases (66% males) during a 4‐year‐period (2008–2011).

Results

Twenty‐eight (60%) patients had healthcare‐associated infections while 15 (32%) received prophylactic quinolone treatment. GPC were found to be the most frequent cause (55%). The most prevalent organisms in a descending order were Streptococcus spp (n = 10), Enterococcus spp (n = 9), Escherichia coli (n = 8), Klebsiella pneumonia (n = 5), methicillin‐sensitive Staphylococcus aureus (n = 4) and coagulase‐negative Staphylococcus spp (n = 3). Nine of the isolated bacteria (19%) were MDR, including carbapenemase‐producing K. pneumonia (n = 4), followed by extended‐spectrum beta‐lactamase‐producing E. coli (n = 3) and Pseudomonas aeruginosa (n = 2). MDR bacteria were more frequently isolated in healthcare‐associated than in community‐acquired infections (100% vs 50%, P = 0.006), in patients receiving long‐term quinolone prophylaxis (67% vs 24%, P = 0.013) and in those with advanced liver disease as suggested by higher MELD score (28 vs 19, P = 0.012). More infections with GNB than GPC were healthcare‐associated (81% vs 42%, P = 0.007). Third‐generation cephalosporin resistance was observed in 49% and quinolone resistance in 47%.

Conclusions

GPC were the most frequent bacteria in culture‐positive SBP and a variety of drug‐resistant microorganisms have emerged. As a result of high rates of resistance in currently recommended therapy and prophylaxis, the choice of optimal antibiotic therapy is vital in the individual patient.
TAM Split Ergativity, Part II
Authors: Coon Jessica
Published: March 2013

This article surveys empirical and theoretical work on Tense‐Aspect‐Mood (‘‘TAM’’) based split ergativity, and offers an account for how it arises. While these splits are typically assumed to represent a unified phenomenon, I demonstrate that non‐ergative portions of split systems exhibit different patterns. I argue that these patterns reflect at least two different triggers of split ergativity: (i) non‐perfective aspects are more likely to be built on complex auxiliary constructions, and (ii) imperfectivity is associated with demoted objects or lower transitivity. Both causes trigger the same result: in the ‘‘split’’ portions of the grammar the transitive subject is not marked with ergative case because it is not a transitive subject. This structural account of split ergativity allows us to avoid positing variable feature inventories on the same functional head (cf. Ura 2006), and also provides a straight‐forward account of the so‐called ‘‘counter‐universal’’ splits (Gildea and de Castro Alves 2010), which cause problems for purely functionalist accounts (e.g. DeLancey 1981). Furthermore, it is shown that the factors which trigger these splits are not limited to ergative languages, but are present cross‐linguistically—they are not visible in nominative‐accusative systems because (by definition) there is no visible difference between transitive and intransitive subjects. The prevalence of splits in ergative systems is thus not taken to reflect any deep instability of ergativity.
Resistance of Arabidopsis thaliana to the green peach aphid, Myzus persicae, involves camalexin and is regulated by microRNAs
Authors: Kettles Graeme J. , Drurey Claire , Schoonbeek Henk‐jan , Maule Andy J. , Hogenhout Saskia A.
Published: March 2013

Small RNAs play important roles in resistance to plant viruses and the complex responses against pathogens and leaf‐chewing insects. We investigated whether small RNA pathways are involved in Arabidopsis resistance against a phloem‐feeding insect, the green peach aphid (Myzus persicae).

We used a 2‐wk fecundity assay to assess aphid performance on Arabidopsis RNA silencing and defence pathway mutants. Quantitative real‐time polymerase chain reaction was used to monitor the transcriptional activity of defence‐related genes in plants of varying aphid susceptibility. High‐performance liquid chromatography‐mass spectrometry was employed to measure the accumulation of the antimicrobial compound camalexin. Artificial diet assays allowed the assessment of the effect of camalexin on aphid performance.

Myzus persicae produces significantly less progeny on Arabidopsis microRNA (miRNA) pathway mutants. Plants unable to process miRNAs respond to aphid infestation with increased induction of PHYTOALEXIN DEFICIENT3 (PAD3) and production of camalexin. Aphids ingest camalexin when feeding on Arabidopsis and are more successful on pad3 and cyp79b2/cyp79b3 mutants defective in camalexin production. Aphids produce less progeny on artificial diets containing camalexin.

Our data indicate that camalexin functions beyond antimicrobial defence to also include hemipteran insects. This work also highlights the extensive role of the miRNA‐mediated regulation of secondary metabolic defence pathways with relevance to resistance against a hemipteran pest.
The long pentraxin PTX3: a paradigm for humoral pattern recognition molecules
Authors: Mantovani Alberto , Valentino Sonia , Gentile Stefania , Inforzato Antonio , Bottazzi Barbara , Garlanda Cecilia
Published: March 2013

Pattern recognition molecules (PRMs) are components of the humoral arm of innate immunity; they recognize pathogen‐associated molecular patterns (PAMP) and are functional ancestors of antibodies, promoting complement activation, opsonization, and agglutination. In addition, several PRMs have a regulatory function on inflammation. Pentraxins are a family of evolutionarily conserved PRMs characterized by a cyclic multimeric structure. On the basis of structure, pentraxins have been operationally divided into short and long families. C‐reactive protein (CRP) and serum amyloid P component are prototypes of the short pentraxin family, while pentraxin 3 (PTX3) is a prototype of the long pentraxins. PTX3 is produced by somatic and immune cells in response to proinflammatory stimuli and Toll‐like receptor engagement, and it interacts with several ligands and exerts multifunctional properties. Unlike CRP, PTX3 gene organization and regulation have been conserved in evolution, thus allowing its pathophysiological roles to be evaluated in genetically modified animals. Here we will briefly review the general properties of CRP and PTX3 as prototypes of short and long pentraxins, respectively, emphasizing in particular the functional role of PTX3 as a prototypic PRM with antibody‐like properties.
Getting away with murder: how does the BCL‐2 family of proteins kill with immunity?
Authors: Renault Thibaud T. , Chipuk Jerry E.
Published: March 2013

The adult human body produces approximately one million white blood cells every second. However, only a small fraction of the cells will survive because the majority is eliminated through a genetically controlled form of cell death known as apoptosis. This review places into perspective recent studies pertaining to the BCL‐2 family of proteins as critical regulators of the development and function of the immune system, with particular attention on B cell and T cell biology. Here we discuss how elegant murine model systems have revealed the major contributions of the BCL‐2 family in establishing an effective immune system. Moreover, we highlight some key regulatory pathways that influence the expression, function, and stability of individual BCL‐2 family members, and discuss their role in immunity. From lethal mechanisms to more gentle ones, the final portion of the review discusses the nonapoptotic functions of the BCL‐2 family and how they pertain to the control of immunity.
Reverse vaccinology in the 21st century: improvements over the original design
Authors: Donati Claudio , Rappuoli Rino
Published: March 2013

Reverse vaccinology (RV), the first application of genomic technologies in vaccine research, represented a major revolution in the process of discovering novel vaccines. By determining their entire antigenic repertoire, researchers could identify protective targets and design efficacious vaccines for pathogens where conventional approaches had failed. Bexsero, the first vaccine developed using RV, has recently received positive opinion from the European Medicines Agency. The use of RV initiated a cascade of changes that affected the entire vaccine development process, shifting the focus from the identification of a list of vaccine candidates to the definition of a set of high throughput screens to reduce the need for costly and labor intensive tests in animal models. It is now clear that a deep understanding of the epidemiology of vaccine candidates, and their regulation and role in host‐pathogen interactions, must become an integral component of the screening workflow. Far from being outdated by technological advancements, RV still represents a paradigm of how high‐throughput technologies and scientific insight can be integrated into biotechnology research.
Wiskott‐Aldrich syndrome: a comprehensive review
Authors: Massaad Michel J. , Ramesh Narayanaswamy , Geha Raif S.
Published: March 2013

Wiskott‐Aldrich syndrome (WAS) is a rare X‐linked primary immunodeficiency characterized by microthrombocytopenia, eczema, recurrent infections, and an increased incidence of autoimmunity and malignancies. The disease is caused by mutations in the WAS gene expressed exclusively in hematopoietic cells. WAS protein (WASp) is a multidomain protein that exists in complex with several partners that play important roles in its function. WASp belongs to a family of proteins that relay signals from the surface of the cell to the actin cytoskeleton. Mutations in the WAS gene have various effects on the level of WASp, which, in turn, correlates with the severity of the disease. In addition to WAS, mutations in the WAS gene can result in the mild variant X‐linked thrombocytopenia, or in X‐linked neutropenia, characterized by neutropenia with myelodysplasia. The absence of functional WASp leads to a severe clinical phenotype that can result in death if not diagnosed and treated early in life. The treatment of choice with the best outcome is hematopoietic stem cell transplantation, preferably from a matched related donor.
COMMAND AND MOTIVATION: HOW THE PERCEPTION OF EXTERNAL INTERVENTIONS RELATES TO INTRINSIC MOTIVATION AND PUBLIC SERVICE MOTIVATION
Authors: JACOBSEN CHRISTIAN BØTCHER , HVITVED JOHAN , ANDERSEN LOTTE BØGH
Published: March 2013

Motivated employees are crucial to organizations, but external interventions such as command systems and financial incentives may decrease motivation. If these external interventions are perceived to be controlling, they are expected to crowd out intrinsic motivation. This may also apply to other types of autonomous motivation such as public service motivation. The perception of external interventions is thus expected to be pivotal. This article investigates how the perception of a specific command system (obligatory student plans) is associated with intrinsic motivation and public service motivation. Using a dataset consisting of 3230 schoolteachers in Denmark, a structural equation model shows that the perception of obligatory student plans as controlling is negatively associated with all of the investigated types of employee motivation, supporting the idea that motivation crowding can occur.
Protein C deficiency as the major cause of thrombophilias in childhood
Authors: Ohga Shouichi , Ishiguro Akira , Takahashi Yukihiro , Shima Midori , Taki Masashi , Kaneko Masatoki , Fukushima Kotaro , Kang Dongchon , Hara Toshiro ,   Japan Childhood Thrombophilia Study Group
Published: March 2013

Genetic predisposition of thromboembolism depends on the racial background. Factor V Leiden (G1691A) and factor II mutation (G20210A) are the leading causes of inherited thrombophilias in Caucasians, but are not found in Asian ancestries. Protein S (PS), protein C (PC) and antithrombin (AT) activity are reportedly low in 65% of adult Japanese patients with deep vein thrombosis. Approximately half of the patients with each deficiency carry the heterozygous mutation of PS (PROS1; 20%), PC (PROC; 10%), and AT genes (SERPINC1: 5%). Recently, several studies have revealed an outline of inherited thrombophilias in Japanese children. Congenital thrombophilias in 48 patients less than age 20 years consisted of 45% PC deficiency, 15% PS deficiency and 10% AT deficiency, along with other causes. All PS‐ and AT‐deficient patients had a heterozygous mutation of the respective gene. On the other hand, PC‐deficient patients were considered to carry the homozygous or compound heterozygous mutation in 50%, the heterozygous mutation in 25%, and unknown causes in the remaining 25% of patients. Half of unrelated patients with homozygous or compound heterozygous PROC mutations carried PC‐nagoya (1362delG), while their parents with its heterozygous mutation were asymptomatic. Most of the PC‐deficient patients developed intracranial lesion and/or purpura fulminans within 2 weeks after birth. Non‐inherited PC deficiency also conveyed thromboembolic events in early infancy. The molecular epidemiology of thrombosis in Asian children would provide a clue to establish the early intervention and optimal anticoagulant therapy in pediatric PC deficiency.
Genes and growth performance in crustacean species: a review of relevant genomic studies in crustaceans and other taxa
Authors: Jung Hyungtaek , Lyons Russell E. , Hurwood David A. , Mather Peter B.
Published: March 2013

Global aquaculture has expanded rapidly to address the increasing demand for aquatic protein needs and an uncertain future for wild fisheries. To date, however, most farmed aquatic stocks are essentially wild and little is known about their genomes or the genes that affect important economic traits in culture. Biologists have recognized that recent technological advances including next generation sequencing (NGS) have opened up the possibility of generating genome wide sequence data sets rapidly from non‐model organisms at a reasonable cost. In an era when virtually any study organism can ‘go genomic’, understanding gene function and genetic effects on expressed quantitative trait locus phenotypes will be fundamental to future knowledge development. Many factors can influence the individual growth rate in target species but of particular importance in agriculture and aquaculture will be the identification and characterization of the specific gene loci that contribute important phenotypic variation to growth because the information can be applied to speed up genetic improvement programmes and to increase productivity via marker‐assisted selection (MAS). While currently there is only limited genomic information available for any crustacean species, a number of putative candidate genes have been identified or implicated in growth and muscle development in some species. In an effort to stimulate increased research on the identification of growth‐related genes in crustacean species, here we review the available information on: (i) associations between genes and growth reported in crustaceans, (ii) growth‐related genes involved with moulting, (iii) muscle development and degradation genes involved in moulting and (iv) correlations between DNA sequences that have confirmed growth trait effects in farmed animal species used in terrestrial agriculture and related sequences in crustacean species. The information in concert can provide a foundation for increasing the rate at which knowledge about key genes affecting growth traits in crustacean species is gained.
Sustainability issues related to feeding salmonids: a Canadian perspective
Authors: Sarker Pallab Kumer , Bureau Dominique P. , Hua Katheline , Drew Murray D. , Forster Ian , Were Keith , Hicks Brad , Vandenberg Grant W.
Published: March 2013

The issue of sustainability of salmonid culture has been the focus of considerable media coverage and debate between environmental activists and aquaculture industry stakeholders, particularly regarding the use of ingredients derived from wild fisheries (fishmeal and fish oil) in salmonid feeds. This study attempts to summarize recent data and to calculate the conversion efficiency of feed resources by Canadian farmed salmon in order objectively to assess the sustainability of this industry in this regard. Using updated information regarding domestic aquafeeds this review reports advances that have been made in diet formulation, fish in–fish out (FIFO) and feed conversion ratios (FCR) and demonstrates that production efficiency of farmed salmonids has significantly improved over time due to continued innovations in the aquafeed sector. The results suggest that the Canadian salmon aquaculture industry efficiently converts wild fish resources into high‐value fish products.
A review of the nutrition and feeding management of farmed tilapia throughout the culture cycle
Authors: Ng Wing‐Keong , Romano Nicholas
Published: March 2013

Tilapia is the second most farmed fish group worldwide and over the past decade has quadrupled in production, largely due to their many characteristics conducive to aquaculture conditions as well as to the high marketability and relatively stable market prices. To keep pace with this rapid expansion, tilapia aquaculture will rely increasingly on more sustainable practices, but this must not be at the expense of decreased productivity, increased cost or compromised product quality. Since feed constitutes the major operating cost of tilapia farming, understanding their nutritional requirements, factors that may influence these requirements and implementing the most appropriate feeding management strategy is essential for the continued sustainability and scalability of the global tilapia industry. This review addressed these concerns by providing an overview of published nutrient requirement data and offered practical recommendations to the nutrition and feeding management of farmed tilapia, from broodstock to finishing feeds. The first section of this review extensively discusses the dietary protein/amino acids, lipids/fatty acids, carbohydrates, vitamin and mineral requirements of tilapia. Alternatives to marine‐based ingredients, which are used increasingly in tilapia feeds, are also discussed. This is followed by discussing practical feed management aspects at the commercial farm level including feed formulations, feed types and feeding rates/frequency throughout the culture cycle. Recent research indicating significant differences in nutrient requirements and utilization efficiencies of improved tilapia strains versus non‐improved strains are highlighted. This review aims to provide a comprehensive overview of tilapia nutrition and thus contributes to the continued global expansion of tilapia farming and the demand for their products.
Physician‐performed ultrasound can accurately screen for a vulnerable intercostal artery prior to chest drainage procedures
Authors: Salamonsen Matthew , Dobeli Karen , McGrath David , Readdy Craig , Ware Robert , Steinke Karin , Fielding David
Published: March 2013

Background and objective

Laceration of the intercostal artery during pleural procedures is a rare but serious complication. This study evaluates the utility of thoracic ultrasound (US) to screen for a vulnerable vessel compared with the gold standard computed tomography (CT).

Methods

Before undergoing contrast‐enhanced CT chest, thoracic US was performed on 50 patients with a high‐end and portable machine, and an attempt made to visualize the vessel at three positions across the back to the axilla. These positions were labelled with radio‐opaque fiducial markers. On both US and CT images, the location of the vessel at each position, relative to the overlying rib, was calculated and compared.

Results

The vessel was unshielded by a rib according to CT in 114 of the 133 positions. The sensitivity, specificity and negative predictive value of portable US to image the vessel, when it was within the intercostal space on CT, was 0.86, 0.30 and 0.27 respectively. The performance of a high‐end machine was not significantly different. The median time required for a pulmonologist to locate the vessel was 42 s and 18 s for the portable and high‐end US respectively.

Conclusions

US can be used to screen for a vulnerable vessel prior to pleural procedures, in a time amenable to use in clinical practice. Further, it is achievable by a pulmonologist using a portable US machine. If thoracentesis or chest tube insertion is being performed on a patient at increased risk of bleeding, screening for a vulnerable vessel with US prior to beginning the procedure is recommended.
Climate and Skin Function: An Overview
Authors: Singh Babu , Maibach Howard
Published: March 2013

Background

Climates of the world are diverse and produce changes in skin integrity and functioning. Evidence on skin and its response to severe climates is limited, but information can be inferred from data characterizing skin under controlled climate conditions using noninvasive bioengineering techniques.

Methods

A literature search was conducted on the effects on major climate conditions on skin integrity and function.

Results

Exposure of murine skin to low humidity promotes a hyperproliferative and proinflammatory response, which can be prevented with topical agents or occlusion. Transepidermal water loss (TEWL) and average skin temperature (Tsk) is highly sensitive to climate or ambient temperature (Tambient). High altitudes leave skin more susceptible to UV radiation and even brief exposures cause surface changes. Pollution can result external skin aging and may be a risk factor for exacerbation of dermatoses.

Conclusion

Further research is needed to understand skin properties and functioning in harsh climates to provide insight into optimal skin care for individuals living in such conditions.
Nailfold capillaroscopy in systemic sclerosis: Is there any difference between videocapillaroscopy and dermatoscopy?
Authors: Dogan Sibel , Akdogan Ali , Atakan Nilgün
Published: March 2013

Background

Vasculopathy is known to destroy nailfold capillary pattern (NCP) in systemic sclerosis (SSc). There are several methods for the evaluation of NCP of which the most common are dermatoscopy and videocapillaroscopy (VCAP). No study has been reported in the literature comparing these two techniques for their diagnostic value.

Objective

To compare the diagnostic value of dermatoscopy and VCAP which are widely used to determine changes in the NCP in SSc patients.

Methods

A total of 382 nailfolds were visualized. NCP was evaluated in 39 SSc patients using dermatoscopy and VCAP. Defined dermatoscopic groups were matched with early, active and late phase NCP groups determined by VCAP for comparisons.

Results

Both dermatoscopy and VCAP demonstrated distinct NCP of SSc efficiently. According to dermatoscopic NCP, capillary dilatation, giant capillaries and disrupted vascular configuration were able to be visualized. VCAP revealed early phase NCP in N = 8 (20,5%), active phase in N = 18 (46,2%) and late phase NCP in N = 13 (33.3%) of the patients. Statistical evaluation of grouped data resulted a Cohen kappa value (K) = 0,527. Although VCAP was able to facilitate a more detailed evaluation of NCP, there was no difference between dermatoscopy and VCAP for the identification of distinct NCP in SSc.

Conclusion

We suggest that dermatoscopy is efficient enough to identify pathognomonic changes in NCP in SSc as well as VCAP and find dermatoscopy as a very easy applicable and convenient method than VCAP although VCAP facilitates a more detailed evaluation of NCP.
Flow Structures in the Tip Region for a Transonic Compressor Rotor
Authors: Du Juan , Lin Feng , Chen Jingyi , Nie Chaoqun , Biela Christoph
Published: March 2013

Numerical simulations are carried out to investigate flow structures in the tip region for an axial transonic rotor, with careful comparisons with the experimental results. The calculated performance curve and two-dimensional (2D) flow structures observed at casing, such as the shock wave, the expansion wave around the leading edge, and the tip leakage flow at peak efficiency and near-stall points, are all captured by simulation results, which agree with the experimental data well. An in-depth analysis of three-dimensional flow structures reveals three features: (1) there exists an interface between the incoming main flow and the tip leakage flow, (2) in this rotor the tip leakage flows along the blade chord can be divided into at least two parts according to the blade loading distribution, and (3) each part plays a different role on the stall inception mechanism in the leakage flow dominated region. A model of three-dimensional flow structures of tip leakage flow is thus proposed accordingly. In the second half of this paper, the unsteady features of the tip leakage flows, which emerge at the operating points close to stall, are presented and validated with experiment observations. The numerical results in the rotor relative reference frame are first converted to the casing absolute reference frame before compared with the measurements in experiments. It is found that the main frequency components of simulation at absolute reference frame match well with those measured in the experiments. The mechanism of the unsteadiness and its significance to stability enhancement design are then discussed based on the details of the flow field obtained through numerical simulations.
Uncertainty Quantification and Conjugate Heat Transfer: A Stochastic Analysis
Authors: Montomoli F. , D’Ammaro A. , Uchida S.
Published: March 2013

Conjugate heat transfer is gaining acceptance for predicting the thermal loading in high pressure nozzles. Despite the accuracy nowadays of numerical solvers, it is not clear how to include the uncertainties associated to the turbulence level, the temperature distribution, or the thermal barrier coating thickness in the numerical simulations. All these parameters are stochastic even if their value is commonly assumed to be deterministic. For the first time, in this work a stochastic analysis is used to predict the metal temperature in a real high-pressure nozzle. The domain simulated is the high pressure nozzle of an F-type Mitsubishi Heavy Industries gas turbine. The complete coolant system is included: impingement, film, and trailing edge cooling. The stochastic variations are included by coupling uncertainty quantification methods and conjugate heat transfer. Two uncertainty quantification methods have been compared: a probabilistic collocation method (PCM) and a stochastic collocation method (SCM). The stochastic distribution of thermal barrier coating thickness, used in the simulations, has been measured at the midspan. A Gaussian distribution for the turbulence intensity and hot core location has been assumed. By using PCM and SCM, the probability to obtain a specific metal temperature at midspan is evaluated. The two methods predict the same distribution of temperature with a maximum difference of 0.6%, and the results are compared with the experimental data measured in the real engine. The experimental data are inside the uncertainty band associated to the CFD predictions. This work shows that one of the most important parameters affecting the metal temperature uncertainty is the pitch-wise location of the hot core. Assuming a probability distribution for this location, with a standard deviation of 1.7 deg, the metal temperature at midspan can change up to 30%. The impact of turbulence level and thermal barrier coating thickness is 1 order of magnitude less important.
The Design Space Boundaries for High Flow Capacity Centrifugal Compressors
Authors: Rusch Daniel , Casey Michael
Published: March 2013

A methodology has been derived allowing a fast preliminary assessment of the design of centrifugal compressors specified for high specific swallowing capacity. The method is based on one-dimensional (1D) design point values using classical turbomachinery analysis to determine the inlet geometry for the maximum mass flow function. The key results are then expressed in a series of diagrams which draw out the nature of the conflicting boundary conditions of the design. In particular, it is shown how the inlet casing relative Mach number causes the design flow coefficient to decrease with the total pressure ratio and determines the inlet eye diameter. Physically based boundaries of operation are added to the diagrams giving guidelines for the proper choice of specification values to the designer. In addition, links are given to some well-known impeller efficiency correlations, so that a preliminary estimate of the performance can be made. Comparisons are made with a range of compressor data which supports the approach. The derived methodology allows any given specifications to be checked rapidly for feasibility and development risk or can be used to define a challenging specification for the design of a new product.
Experimental Investigation of a New Grid Cathode Design Method in Electrochemical Machining
Authors: Yonghua Lu , Dongbiao Zhao , Kai Liu
Published: March 2013

This paper focuses on the grid cathode design in electrochemical machining (ECM) in order to develop a new cathode design method for realizing a breakthrough: one cathode can produce different workpieces with different profiles. Three types of square cells, 2.5 mm × 2.5 mm, 3 mm × 3 mm, and 4 mm × 4 mm in size and three types of circular cells, with diameters of 1.5, 2.0, and 2.5 mm are utilized to construct the plane, slant, and blade grid cathode. The material of the cathode and anode is CrNi18Ti9 and the ingredients of the electrolyte are 15% NaCl and 15% NaNO3. A large number of experiments are conducted by using different grid cathodes to analyze the effects of the shape and size of the grid cell on the machining process. In addition, we compare the workpiece quality and machining error between using the grid cathode and the unitary cathode and discuss the reasons for the errors in order to obtain a better surface quality of the workpiece. Our research supports the conclusions that the grid cathode can be used to manufacture workpieces with complex shapes, the workpiece quality is better if the square cell is smaller and, for the same equivalent area, the circular grid cathode produces a better quality workpiece than the square grid cathode.
Effects of a low- or a high-carbohydrate diet on performance, energy system contribution, and metabolic responses during supramaximal exercise
Authors: Lima-Silva Adriano E. , Pires Flavio O. , Bertuzzi Romulo , Silva-Cavalcante Marcos D. , Oliveira Rodrigo S.F. , Kiss Maria Augusta , Bishop David
Published: March 2013

The purpose of the present study was to examine the effects of a high- or low-carbohydrate (CHO) diet on performance, aerobic and anaerobic contribution, and metabolic responses during supramaximal exercise. Six physically-active men first performed a cycling exercise bout at 115% maximal oxygen uptake to exhaustion after following their normal diet for 48 h (∼50% of CHO, control test). Seventy-two hours after, participants performed a muscle glycogen depletion exercise protocol, followed by either a high- or low-CHO diet (∼70 and 25% of CHO, respectively) for 48 h, in a random, counterbalanced order. After the assigned diet period (48 h), the supramaximal cycling exercise bout (115% maximal oxygen consumption) to exhaustion was repeated. The low-CHO diet reduced time to exhaustion when compared with both the control and the high-CHO diet (−19 and −32%, respectively, p < 0.05). The reduced time to exhaustion following the low-CHO diet was accompanied by a lower total aerobic energy contribution (−39%) compared with the high-CHO diet (p < 0.05). However, the aerobic and anaerobic energy contribution at the shortest time to exhaustion (isotime) was similar among conditions (p > 0.05). The low-CHO diet was associated with a lower blood lactate concentration (p < 0.05), with no effect on the plasma concentration of insulin, glucose and K+ (p > 0.05). In conclusion, a low-CHO diet reduces both performance and total aerobic energy provision during supramaximal exercise. As peak K+ concentration was similar, but time to exhaustion shorter, the low-CHO diet was associated with an earlier attainment of peak plasma K+ concentration.
Impact and damage to structures during the 27 February 2010 Chile tsunami
Authors: Palermo Dan , Nistor Ioan , Saatcioglu Murat , Ghobarah Ahmed
Published: March 2013

Damage to structures and infrastructure due to the Chile tsunami of 27 February 2010, is presented. Robust, modern engineered structures performed well during this tsunami and, generally, damage only to non-structural components was evident. The majority of damage was sustained by non-engineered residential homes located within the inundation zone. These dwellings consisted of either light timber frame construction or concrete frame construction with brick masonry infill walls. Many of the dwellings incorporated sheet metal as exterior cladding or roofing. The hydrodynamic (drag) forces, impulsive loading, hydrostatic forces, buoyant forces, and debris impact loading were probable sources during the tsunami causing the observed damage. Failures included punching of brick masonry infill walls, partial and complete collapse of load bearing elements such as columns, and sliding and unseating failures of second storey levels and roofs. A discussion of the state of the art in tsunami design practice is also provided.
Collision-induced spectra and current astronomical research
Authors: Abel Martin , Frommhold Lothar
Published: March 2013

Collision-induced spectra are the spectra of complexes of two or more atoms or molecules in a “fly-by” collisional encounter. Collision-induced absorption (CIA) has been observed in many dense gases and gas mixtures, in most cases at infrared frequencies in the form of quasi continua, and also in liquids and solids. CIA spectra of several binary complexes have been computed using modern quantum chemical methods, combined with molecular scattering theory, which couples the collisional complex to the radiation field as usual in other spectroscopic work. Binary collisional systems, such as H2 interacting with another H2 molecule, or with a helium or hydrogen atom, are first candidates for such computational work, owing to their small number of electrons and the astrophysical interest in such systems. The computed CIA spectra are found to be in close agreement with existing laboratory measurements of such spectra. Laboratory measurements exist at a limited selection of temperatures around 300 K and lower, but theory currently also provides CIA data for temperatures up to 9000 K and for higher frequencies (well into the visible), on a dense grid of temperatures and frequencies. For such calculations, detailed potential energy surfaces (PES) of the supermolecular complexes, along with the induced dipole surfaces (IDS), are needed so that the rotovibrational matrix elements of PES and IDS may be computed for the molecules involved, which may be highly rotovibrationally excited. Modern astronomical research needs opacity tables for analyses of the atmospheres of “cool” objects, such as cool white dwarfs, solar and extrasolar planets and their big moons, cool main sequence stars, and “first” stars, which are briefly described in a concluding section.
Effects of tempol on endothelial and vascular dysfunctions and insulin resistance induced by a high-fat high-sucrose diet in the rat
Authors: Bourgoin Frédéric , Bachelard Hélène , Badeau Mylène , Larivière Richard , Nadeau André , Pitre Maryse
Published: March 2013

We investigated the effects of treatment with tempol (an antioxidant) on vascular and metabolic dysfunction induced by a high-fat high-sucrose (HFHS) diet. Rats were randomized to receive an HFHS or chow diet with or without tempol treatment (1.5 mmol·(kg body mass)−1·day−1) for 4 weeks. Blood pressure, heart rate, and blood flow were measured in the rats by using intravascular catheters and Doppler flow probes. Insulin sensitivity and vascular responses to insulin were assessed during a euglycemic–hyperinsulinemic clamp. In-vitro studies were performed to evaluate vascular reactivity and endothelial and inducible nitric oxide synthase (eNOS; iNOS) expression in vascular and muscle tissues. Endothelin, nitrotyrosine, and NAD(P)H oxidase expressions were determined in vascular tissues, and glucose transport activity and glucose transporter 4 (GLUT4) expression were examined in muscles. Tempol treatment was found to prevent alterations in insulin sensitivity, glucose transport activity, GLUT4 expression, and vascular reactivity, and to prevent increases in plasma insulin, blood pressure, and heart rate noted in the untreated HFHS-fed rats. These were associated with increased levels of eNOS expression in vascular and muscle tissues, but reductions in nitrotyrosine, endothelin, NAD(P)H oxidase, and iNOS expressions. Therefore, oxidative stress induced by a relatively short-term HFHS diet could contribute to the early development of vascular and metabolic abnormalities in rats.
THE CLASSICAL LIMIT OF REPRESENTATION THEORY OF THE QUANTUM PLANE
Authors: IP IVAN C. H.
Published: March 2013

We showed that there is a complete analogue of a representation of the quantum plane [Formula: see text] where |q| = 1, with the classical ax+b group. We showed that the Fourier transform of the representation of [Formula: see text] on [Formula: see text] has a limit (in the dual corepresentation) toward the Mellin transform of the unitary representation of the ax+b group, and furthermore the intertwiners of the tensor products representation has a limit toward the intertwiners of the Mellin transform of the classical ax+b representation. We also wrote explicitly the multiplicative unitary defining the quantum ax+b semigroup and showed that it defines the corepresentation that is dual to the representation of [Formula: see text] above, and also correspond precisely to the classical family of unitary representation of the ax+b group.
ELECTRONIC PROPERTIES OF A HYDROGENIC IMPURITY IN A QUANTUM WIRE WITH V-SHAPED CROSS-SECTION: SPIN-ORBIT COUPLING, RELATIVISTIC CORRECTION AND CONDUCTANCE
Authors: KHORDAD R. , BAHRAMIYAN H.
Published: March 2013

The effects of spin-orbit coupling (SOC) and relativistic correction (RC) on the energy levels of a hydrogenic impurity in a GaAs/Ga 1-x Al x As quantum wire are studied. The quantum wire has a V-shaped cross-section and the impurity located in its center. Our numerical calculations have done using a variational procedure within the effective mass approximation. Our results show that (i) the splitting due to the SOC decreases with increasing the wire width, (ii) the SOC and RC increase when the concentration increases, (iii) the SOC is zero for l = 0 (l is angular momentum) and nonzero for l ≠ 0, (iv) for a given wire width, the RC is different for l = 0 and l = 1 due to expectation values of [Formula: see text] and [Formula: see text] (r is distance between the electron and impurity). We also computed the conductance of the quantum wire with and without impurity.
ON THE ENERGY–MOMENTUM FLUX IN GÖDEL-TYPE MODELS
Authors: ULHOA S. C. , SANTOS A. F. , AMORIM R. G. G.
Published: March 2013

In this paper, we work in the context of Teleparallelism Equivalent to General Relativity (TEGR) in order to construct the energy–momentum flux for Gödel-type solutions of Einstein's equations. We use an stationary observer, which is settled by the tetrad choice, to obtain the gravitational pressure for each direction of space in cartesian coordinates. Then, we write down the total pressure for each direction in terms of the pressure of the fluid, thus we are able to identify the role of the gravitational pressure.
AMORPHOUS COPPER DISELENIDE THIN FILMS DOPED WITH GALLIUM AND INDIUM BY LASER-INDUCED DOPING
Authors: KIM NAM-HOON , JEON JI EUN , CHO GEUM-BAE , LEE WOO-SUN , CHOI DONG-YOU
Published: March 2013

The laser-induced doping of amorphous copper diselenide (α- CuSe 2) thin film with gallium (Ga) and indium (In) was performed to control/improve their electrical and optical properties. The CuSe 2 thin films sputtering-deposited using a CuSe 2 alloy target were amorphous and remained amorphous after doping with Ga/In . Doping of group-III-elements enhanced the absorption ability of the α- CuSe 2 thin films in the near-infrared spectral regions (800–1500 nm). The insufficient laser-irradiation time to Ga attributed the nonuniform distribution of Ga content around the surface of the α- CuSe 2 thin films, which prevented the incident light from transiting through the thin film, particularly in the visible spectral region (400–800 nm). Consequently, the absorption coefficient increased with the nonuniformly distributed specimen in the visible and near-infrared spectral regions, which improved the mean absorbance of the α- CuSe 2 thin films from 1.03 to 1.66 by decreasing the optical band gap energy from 2.50 eV to 2.10 eV in the same spectral region. The resistivity, carrier concentration and carrier mobility of the α- CuSe 2 thin films were in 3.76×10-4- 3.83×10-3 Ω cm, 1.41×1020-2.00×1021 cm -3 and 9.9–19.4 cm2/Vs, respectively, regardless of doping, making these films suitable as a wide spectral range absorber layer in photovoltaic applications.
KERNEL SUPERVISED DISCRIMINANT PROJECTION AND ITS APPLICATION FOR FACE RECOGNITION
Authors: WANG JIANGUO
Published: March 2013

Subspace analysis is an effective approach for face recognition. In this paper, a novel subspace method, called kernel supervised discriminant projection (KSDP), is proposed for face recognition. In the proposed method, not only discriminant information with intrinsic geometric relations is preserved in subspace, but also complex nonlinear variations of face images are represented by nonlinear kernel mapping. Extensive experiments are performed to test and evaluate the new algorithm. Experimental results on three popular benchmark databases, FERET, Yale and AR, demonstrate the effectiveness of the proposed method, KSDP.
ACTIVE CONTROL OF A MACHINE SUSPENSION SYSTEM SUPPORTED ON A CYLINDRICAL SHELL
Authors: LIU X. , JIN G. , WANG Y. , SHI Y. , FENG X.
Published: March 2013

A numerical study on the active control of a machine suspension system supported on a cylindrical shell aiming to reduce the sound radiation is presented in this paper. In this system, a rigid-body machine is supported on a simply-supported elastic cylindrical shell through four active isolators. A theoretical model is employed and four types of active control strategies including kinetic energy minimization strategy, power flow minimization strategy, squared acceleration minimization strategy and acoustic power minimization strategy are considered, with corresponding active control force obtained by linear quadratic optimal method. Numerical simulations are conducted and detailed results were presented. Active control performance under these four control strategies is compared and analyzed in terms of radiated sound power, and the effect of the number of active actuators is discussed by numerical analysis. The results show that acoustic power minimization strategy has the best performance to reduce the sound power radiated from supporting shell in general. Through numerical simulations, some comprehensive design principles of active control system are discussed at the end.
MODELING BONE CONDUCTION OF SOUND IN THE HUMAN HEAD: II. SIMULATION RESULTS
Authors: GATTO P. , DEMKOWICZ L.
Published: March 2013

We investigate bone conduction of sound in the human head through a fully coupled model based on the fluid–structure interaction. The model was simulated via hp-finite element approximation employing our latest finite element library. The transmission of acoustic energy through non-airborne pathways to the cochlea, the receptor that converts the mechanical signal into electric impulses sent to the brain, is still not fully understood. We believe that our methodology and presented numerical results provide an insight into this fundamental, long standing research problem.
ASSESSMENT OF RPIM SHAPE PARAMETERS FOR SOLUTION ACCURACY OF 2D GEOMETRICALLY NONLINEAR PROBLEMS
Authors: BOZKURT O. YAVUZ , KANBER BAHATTİN , AŞIK M. ZÜLFÜ
Published: March 2013

This study discussed the effects of shape parameters on the radial point interpolation method (RPIM) accuracy in 2D geometrically nonlinear problems. Four finite deformation problems with compressible Neo-Hookean material are numerically solved with the RPIM algorithm using the multi-quadric (MQ) radial basis function. Both regular and irregular node distributions are used. Their displacements and Cauchy stresses are compared for different values of shape parameters and monomial basis. It is found that the shape parameters proposed for linearly elastic problems (q = 1.03, αc = 4) can still be applicable to 2D geometrically nonlinear problems but careful selections should be made for the calculation of stress. For example, when q is used as 1.75 with irregular node distributions, stresses can be calculated more precisely.
TSALLIS ENTROPY COMPOSITION AND THE HEISENBERG GROUP
Authors: KALOGEROPOULOS NIKOS
Published: March 2013

We present an embedding of the Tsallis entropy into the three-dimensional Heisenberg group, in order to understand the meaning of generalized independence as encoded in the Tsallis entropy composition property. We infer that the Tsallis entropy composition induces fractal properties on the underlying Euclidean space. Using a theorem of Milnor/Wolf/Tits/Gromov, we justify why the underlying configuration/phase space of systems described by the Tsallis entropy has polynomial growth for both discrete and Riemannian cases. We provide a geometric framework that elucidates Abe's formula for the Tsallis entropy, in terms the Pansu derivative of a map between sub-Riemannian spaces.
RURAL MICROFINANCE AND CLIENT RETENTION: EVIDENCE FROM MALAWI
Authors: EPSTEIN MARC J. , YUTHAS KRISTI
Published: March 2013

Microfinance institutions (MFIs) have largely focused on urban markets, leaving the rural poor underserved. The high costs of serving rural markets has often been identified as the key impediment to serving these markets, resulting in saturation and heavy competition in urban markets while poor rural clients remain unserved. In this paper, we provide evidence from a sample of over 10,000 microfinance loans in Malawi, that the cost argument has an important flaw. Results show that client retention, a critical aspect of financial sustainability, is significantly higher in rural markets. In addition to being a key financial indicator in an industry where annual client exit rates can exceed 50 percent, client retention is also a key measure of social impact. By operating in rural markets, MFIs may be able to increase both social impact and financial performance.