bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Accelerated Convergence of Genetic Algorithm Using GPU Parallel Operations
Authors: Li Cheng-Chieh , Liu Jung-Chun , Lin Chu-Hsing , Lo Winston
Published: July 2015

The genetic algorithm plays a very important role in many areas of applications. In this research, the authors propose to accelerate the evolution speed of the genetic algorithm by parallel computing, and optimize parallel genetic algorithms by methods such as the island model. The authors find that when the amount of population increases, the genetic algorithm tends to converge more rapidly into the global optimal solution; however, it also consumes greater amount of computation resources. To solve this problem, the authors take advantage of the many cores of GPUs to enhance computation efficiency and develop a parallel genetic algorithm for GPUs. Different from the usual genetic algorithm that uses one thread for computation of each chromosome, the parallel genetic algorithm using GPUs evokes large amount of threads simultaneously and allows the population to scale greatly. The large amount of the next generation population of chromosomes can be divided by a block method; and after independently operating in each block for a few generation, selection and crossover operations of chromosomes can be performed among blocks to greatly accelerate the speed to find the global optimal solution. Also, the travelling salesman problem (TSP) is used as the benchmark for performance comparison of the GPU and CPU; however, the authors did not perform algebraic optimization for TSP.
Recognition of Handwritten Hindi Text Using Middle Region of the Words
Authors: Garg Naresh Kumar , Kaur Lakhwinder , Jindal M. K.
Published: July 2015

Offline handwritten Hindi text recognition is a very tedious task. In this paper, a novel method using middle region of the words for recognition of handwritten Hindi text is proposed. A segmentation based approach is used for recognition. Although many efforts have been made to recognize isolated characters and words, a little work has been done to recognize the offline handwritten Hindi text by segmenting the sentences into lines and lines into words. The uniqueness of this approach lies in the fact that many of the commonly used words can be recognized by matching all the characters in the middle zone even by ignoring the upper modifiers, lower modifiers and half characters. Another advantage is that it is not word specific i.e. any number of words can be added to the list to be recognized. Topological features are used for recognition of characters and efforts are made to correctly extract the features. Results obtained with the proposed technique are very challenging.
Human Cognition in Automated Truing Test Design
Authors: Nayeem Mir Tafseer , Akand Mamunur Rashid , Sakib Nazmus , Kabir Wasi Ul
Published: July 2015

Nowadays, many services in the internet including Email, search engine, social networking are provided with free of charge due to enormous growth of web users. With the expansion of Web services, denial of service (DoS) attacks by malicious automated programs (e.g., web bots) is becoming a serious problem of web service accounts. A HIP, or Human Interactive Proofs, is a human authentication mechanism that generates and grades tests to determine whether the user is a human or a malicious computer program. Unfortunately, the existing HIPs tried to maximize the difficulty for automated programs to pass tests by increasing distortion or noise. Consequently, it has also become difficult for potential users too. So there is a tradeoff between the usability and robustness in designing HIP tests. In their propose technique the authors tried to balance the readability and security by adding contextual information in the form of natural conversation without reducing the distortion and noise. In the result section, a microscopic large-scale user study was conducted involving 110 users to investigate the actual user views compare to existing state of the art CAPTCHA systems like Google's reCAPTCHA and Microsoft's CAPTCHA in terms of usability and security and found the authors' system capable of deploying largely over internet.
Compatibility of Endurance Limit and Fatigue Crack Growth Parameters in Evaluation of Low Alloyed Steel Welded Joint Behaviour
Authors: Čamagić Ivica , Vasić Nemanja , Živković Predrag , Radović Aleksandar , Sedmak Tamara , Burzić Meri , Burzić Zijah
Published: July 2015

Analysis of fracture toughness of high-strength low alloyed steel, Nionikral-70, welded joint constituencies, subjected to variable load is given in this paper, using two parameters. Crack initiation resistance is determined by testing of endurance limit and by designing of Wöhler curves. Crack propagation resistance is determined by testing of crack growth rate, and accordingly determination of Paris equation parameters. Analysis of fracture toughness is given based on testing results, comparing obtained values for base metal, weld metal and heat affected zone.
Mechanical Hardening and Resistance to Cavitation Erosion of the Austenitic Stainless Steels with Varying Proportions of Delta Ferrite
Authors: Salcianu Cornelia Laura , Bordeasu Ilare , Mitelea Ion , Micu Lavinia Madalina
Published: July 2015

The paper analyzes, comparative, the resistance to the cavitation erosion for the X5CrNi18-10 classic steel, with that provided by two another steels, processed experimental, with approx. 0.1 % C, 24% Cr, 18 % , approx. 10% Ni and wich was mechanically hardened by vibro rolling. Cavitation tests were performed on a vibrating device with piezoelectric crystal, in the Laboratory of Hydraulic Machines in Timisoara ( LMHT ), determining the characteristic curves of the variation in time of the mean depth erosion, MDE (t ) and mean depth erosion rate, MDER (t). By mechanical tests and by metallographic investigation is warranted increased erosion resistance after cold plastic deformation and minimization the effect of reduction its to higher proportions of delta ferrite , due to higher chromium content. Conclusions detached, after the investigations, serve designers and processors by stainless steel to chemical composition optimization and to manufacturing processes, in order to increase the lifetime of hydromechanical equipment, such as hydraulic turbines, pumps and throttle butterfly valves on pipelines forced, etc.Keywords: mechanical hardening, characteristic curves, resistance to cavitation, microstructure, chemical elements, mechanical properties
Reduction of Cavitation Erosion of the Bronze CuAl10Ni5Fe2.5Mn1 by Laser Remelting Treatment
Authors: Oancă Octavian Victor , Mitelea Ion , Bordeasu Ilare , Ghera Cristian
Published: July 2015

The paper presents a new procedure for bronze surface hardened by using intensive heating with laser beams (over 103 °C/s) which superficially melts the material. Afterwards the whole mass of the piece is subjected to blast cooling. For the used experimental conditions it was obtained a fine quenching microstructure with high harnesses, till 350 HV 0.5. The resulted structure has extremely fine grains which give an excellent resistance to cavitation erosions, because the dislocations movemement was heavily suppressed. Secondary, the residual compression tensions existing in the superficial layer delay the initiation of the cracks. Tertiary, the effects of bubble implosions are attenuated as a result of the holes realized on the surface by the laser beams treatment. Finally, the power of the laser beams upon the increase of the cavitation resistance was put into evidence.
Evaluation of Secondary Hardening and Microstructure in the Real T24 Steel Weld Joint
Authors: Sondel Martin , Koukal Jaroslav , Schwarz David , Schwarz Drahomir
Published: July 2015

Development of new steels with higher creep resistance must be based on detailed knowledge of strengthening and degradation processes, structural stability at high temperature exposure and their welding. This paper is concerned with the real weld joint hardness and microstructure of progressive low alloy creep resistance T24 steel. These steel is widely used in many power-plant constructions all over the Europe. Welding the T24 steels components is one of the most important technological procedures. The aim of the performed investigation is to evaluate the hardness and microstructure in the heat affected zone (HAZ) and the weld metal. Results of the secondary hardening in the real weld joints after low temperature post weld heat treatment (460°C/48h) and without post weld heat treatment at service temperature are described in this paper. Obtained results are compared to the hardness values of the weld joint post weld heat treated at recommended temperature (740°C). The microstructure of the real weld joints was analysed by transmission electron microscopy (TEM) in order to identify minority phases - MX nanoparticles and/or coarse (M23C6) particles. Secondary hardening of the not heat treated and low temperature heat treated T24 weld joint was proved.
Stresses and Strains in Main Gas Pipelines due to Ramifications
Authors: Pintilie Alexandru , Bormambet Melat , Rădoiu Viorel Bogdan
Published: July 2015

In this paper is presented a study of stresses and strains due ramification to consumers of main gas pipeline. It's numerically analyzed the influence of main pipe's ramification due to modification of mechanical and geometrical parameters.
Modeled loads are based on evaluation of internal forces of thin shell and induced loads by circular weld thermal field. The study of stresses and strain it's made using finite elements method by a static tri dimensional analysis performed both for evaluation of stresses and strains in presence and absence of internal pressure.
The obtained results represent a comparative factor for technical regulation in the safety assessment in operation of natural gas pipelines.
Evaluation of Fracture Toughness for P355NH Steel Subjected to Thermal Cycles Simulation
Authors: Galaţanu Sergiu Valentin , Pascu Romulus , Faur Nicolae
Published: July 2015

The thermal cycles simulator of welding is a complex equipment that reproduces in a specimen thermal cycles of the type caused in the HAZ by welding processes.In this paper, it is presented a comparison between the results obtained by welded joints and thermal cycle simulator specimens, from the material P355NH of 22 mm thickness for pressure vessels. Two types of thermal cycle simulator specimens were used: one specimen without post-simulation heat treatment and one specimen with post-simulation heat treatment.For the welded specimens Mn3Ni1CrMo filler material was used.This paper offers information about the impact energy of specific areas of the welded joints, both for butt welding and thermal cycle simulator specimens.A good correlation was observed between the results of thermal cycle simulation with post-simulation heat treatment and the results obtained by welding.
Structural Connections of Steel Building Frames under Extreme Loading
Authors: Dinu Florea , Dubină Dan , Marginean Ioan , Neagu Calin , Petran Ioan
Published: July 2015

Resistance to progressive collapse under extreme loading is a measure of the structural robustness, and relies primarily on resistance of key elements, continuity between elements and ductility of elements and their connections. In case some hazards occur simultaneously or consecutively in a very short period of time, e.g. fire after explosion or impact, the capacity of the members and connections can be exceeded and this can initiate the progressive collapse of the structure. The paper presents the results of a research program that focused on the ultimate capacity of connection macro-components under large deformation demands and different loading rates. The specimens were extracted from extended end plate bolted beam-to-column connections with different strength and stiffness ratios to the beams.
Design by Qualification Testing of Reduced Beam Section Welded Connections
Authors: Dinu Florea , Dubină Dan , Vulcu Cristian , Neagu Calin
Published: July 2015

Steel moment frames are common systems in multi-storey buildings. Even the relatively low stiffness of the system limits the applicability, they remain popular in seismic applications due to the good dissipation capacity. Considered deemed-to-comply in seismic applications, welded beam to column connections experienced serious damages and even failures during strong seismic earthquakes. These failures included fractures of the beam flange-to-column flange groove welds, cracks in beam flanges, and cracks through the column section. To reduce the risk of brittle failure of welded connections, beam weakening near the ends became popular. To assure the desired behavior, i.e. the development of plastic deformations in the reduced beam section zones rather than at the face of the column, proper detailing and sizing is necessary. Today design provisions are limited to long beams, where the effect of shear stresses may be neglected. The application of the same rules for short beams might be non-conservative, and therefore qualification testing is necessary.
The study presents the qualification testing of reduced beam sections welded connections of short beams. Both monotonic and cyclic tests were performed and numerical models were validated based on the test data.
Optimization of Laser Beam Cutting Process Parameters of Austenitic Materials
Authors: Petronić Sanja , Grujic Biljana , Milovanovic Dubravka S. , Jovicic Radomir
Published: July 2015

Austenitic materials have high demand in modern manufacturing industries due to their improved technological characteristics such as high mechanical strength and hardness, corrosion resistance, heat resistance and wear resistance. Some applications of austenitic materials include elevated pressure and temperature, and require stringent design requirements and close tolerances in manufactured products. Laser cutting is one of the non-conventional cutting processes, used to obtain complex shapes and geometries. In this paper, laser cutting was performed on austenitic material. The laser cutting process parameters are varied with the aim to obtain the optimal process parameters. The geometric and metallurgical characteristics of the cut parts are investigated and compared to the conventional cutting methods of austenitic materials.
Failure Analysis of Ni Based Superalloys Welded Joints
Authors: Buzdugan Ramona Monica , Farbas Nicolae , Crăciunescu Corneliu Marius
Published: July 2015

Ni-based super alloys are used in a wide field of applications like chemical, nuclear, petrochemical and furnace industries, where extreme temperatures, mechanical stresses and corrosive environments are encountered. The paper presents the failure analysis of an assembly used in a petrochemical plant after 40000 functioning hours at high temperatures. The assembly is composed of a catalyst tube made of KHR 35CT and a weldolet made of INCOLOY 800HT welded by GTAW process using INCONNEL 82 as filler material. SEM and EDX analysis were carried out and it was found that the fracture occurred by the weldolet detachment, following the fusion zone. The fracture surface presents grain boundaries precipitations and no major plastic deformations.
Joining of Y2O3-Doped Aluminum Nitride with High Density Graphite by Spark Plasma Sintering
Authors: Tsakiris Violeta , Kappel Wilhelm , Velciu Georgeta , Seitan Cristian , Talpeanu Dorinel , Clicinschi Florentina , Hajdu Carmen , Marinescu Virgil
Published: July 2015

High density graphite disks and aluminum nitride ceramics powders have been utilized to obtain joints by Spark Plasma Sintering technique. The joining was carried out in vacuum, at temperatures of 1700°C, 1800°C and 1900°C, under the pressure of 50 MPa with a constant dwelling time of 5 minutes The AlN ceramics to be joined were also synthesized by ceramic technology standard route by using AlN powders and 2.5 % wt.Y2O3 powders as sintering additive, which were added in order to increase densification rate and by thus, thermal conductivity. The joining of AlN/C was performed both without and with the aid of a ceramic powder composite AlN+Y2O3+C film, as interlayer. Besides the crystalline phases (AlN and C), the Al5Y3O12 compounds with a cubic crystallographic structure were identified by X-ray diffraction. The optical microscopy images revealed that all samples, both without and with film as interlayer, had strong joined areas, without any defects and discontinuities at interfaces. The Vickers microhardness and Young Modulus values measured by nanoindentation have shown that using of the film as intermediary layer was leading to the highest values of mechanical properties (HV = 8 – 23 GPa and E= 227-512 GPa) at the AlN/C joints interfaces.
Investigations on Structural Integrity of a Petrochemical Component
Authors: Murariu Alin Constantin
Published: July 2015

Petrochemical equipment and installations are vital components of a National energy system. Age and their wear, uncertainty related to their technical status, lack of automation and monitoring systems slows the implementation process of the risk management system in the context of the new regulations on safety in operation and environmental protection requirements. The paper presents an inspection, related to structural integrity of a petrochemical plant component. As a complementary technique, of the classical mechanical tests, an advanced method of examination SEM was used. Combining the results led to highlighting and a comprehensive understanding of the failure mechanisms of the tested materials, impacting on the confidence of the risk level and the safety in operation of inspected components.
Transformation Reactions by TIG Welded Joints of the Alloyed Steels Used for Endless Saw Blades
Authors: Mitelea Ion , Uţu Ion Dragoş , Ochian Daniel , Burca Mircea
Published: July 2015

Butt welding by TIG method using a low alloyed steel wire with solid state transformation point, G3Si1, having 1 mm diameter is a feasible solution for both unique and small series production and for saw blades reshuffling made of dissimilar steels (rapid steel HS 2-10-1-8 for the active part and X32CrMoV4-1 steel for the tool holder).This paper analyses the structural and chemical composition modifications occurred in the heterogeneous welded joints areas by endless saw blades. The phenomena which manage the continuous evolution of the weld chemical composition are highlighted by Energy Dispersive X-Ray Analysis (EDX) and Scanning Electron Microscopy (SEM).
Advanced Metallic Materials with Amorphous Structure Used for Resistance Brazing Joints
Authors: Codrean Cosmin , Magda Aurelian , Burca Mircea , Buzdugan Dragoş
Published: July 2015

In this paper will be presented experimental researches on development advanced alloys with amorphous structures based on Ni and Cu for resistance brazing joints. The main advantages of these amorphous alloys in shape of ribbons are their ductility and flexibility. These ribbons are obtained by ultra-rapid cooling of the melt. Using resistance brazing process, were obtained brazing joints of stainless steel and copper strips. The joints were mechanical and structural analysed. It was performed mechanical shear test on the brazed joints to establish the shear strength of the joints, and also it was performed structural investigation to emphasize the microscopic structure and the structural transformations that take place in the base material and brazing alloys during the brazing process.
Reconditioning of Crankshaft in the Automotive Industry by Using TIG Welding
Authors: Chivu Vîrlan Oana Roxana , Rontescu C. , Cicic Dumitru Titi , Vasile Mihai
Published: July 2015

It is well known that, due to their working under severe conditions, the crankshafts in the automotive industry yield in the area of the crankpin journals and that buying a new crankshaft means high costs. Due to these reasons, various welding processes are frequently used for repairs. Certain welding processes are difficult to apply because the heat energy introduced into the parts during the welding process is very high and will lead to deformations and residual stresses and to structural changes. The paper contains the experimental results related to the effect of applying the WIG welding process to certain characteristics of the deposit layer: hardness, heat affected zone, structure etc.
The Evaluation of Different Types of Welding in the Orthodontic Expanders
Authors: Szuhanek Camelia , Fleșer Traian
Published: July 2015

The purpose of our paper was to evaluate the effect of different methods of welding in the laboratory procedures of orthodontic expanders. The results of flame, ultrasound, resistance and laser welding methods were evaluated by means of mechanical testing. Metallographic investigations were also used in order to compare the results of different welding testing. A combination of techniques which offer optimum mechanical, biological, physical and chemical properties must be selected. New results are presented in comparison to previous research with published results.
Structure and Mechanical Properties of AlSi10Mg Fabricated by Selective Laser Melting Additive Manufacturing (SLM-AM)
Authors: Rosenthal Idan , Nahmany Moshe , Stern Adin , Frage Nachum
Published: July 2015

Additive manufacturing (AM) of metals is a relatively novel fabrication approach with growing interests in many industries. The AM process is based on building products originating from 3-D computer models, through localized melting of powder in a layered structure. The present research focused on the metallurgical investigation of AM AlSi10Mg parts fabricated by SLM-AM. The macrostructure of the product is a collage of solidified track segments, which were remelted several times by the adjacent neighboring tracks. The microstructure consists of fine cellular dendrites, which reflect high thermal gradients and rapid progression of the scanning laser during the AM process. The building strategy is crucial for the successful layer by layer additive process and the properties of the components. It was established that AM products yield higher mechanical properties than that for the parts fabricated by casting. Feasibility of AM parts joining by Electron Beam Welding (EBW) method is discussed.
Diffusion Bonding of Ceramics by Spark Plasma Sintering (SPS) Apparatus
Authors: Aroshas Ron , Kalabukhov Sergey , Stern Adin , Frage Nachum
Published: July 2015

Alumina, Silicon Carbide, Boron Carbide and Magnesium Aluminate Spinel were directly joined by a Spark Plasma Sintering (SPS) apparatus. The optimal parameters for joining (temperature, holding time and applied pressure) were experimentally found. The joined regions were investigated using scanning electron microscopy (SEM) ultrasonic and micro hardness testing. Alumina, Boron Carbide and Silicon Carbide parts were successfully joined at 1300, 1800 and 1900°C, respectively, for 30 min under argon atmosphere (10- 2 torr) and 40 MPa uniaxial pressure. Spinel parts were successfully joined at 1300°C for 60 min. Micro hardness of the interfacial regions were similar to those of the bonded specimens. The effect of a prolonged heat treatment on the microstructural evolution of the joined regions was investigated and the grain growth mechanism was discussed.
Impact of umbilical cord cleansing with 4% chlorhexidine on rate of omphalitis and separation time among newborns in Khartoum state, Sudan
Authors: Kheir Abdelmoneim E.M. , Mustafa Amna M.A. , Osman Awatif A.
Published: July 2015

Infection of the umbilical cord remains high in developing countries with subsequent increase in neonatal mortality rates. This may be due to the practice of applying potentially harmful substances to the freshly cut cord. The aim of this study was to assess the impact of umbilical cord care with 4% chlorhexidine on the rate of omphalitis and separation time among newborns in Khartoum State. This was a quasi-experimental research design that was carried out in the main maternity hospitals of Khartoum state between February and August 2012. One hundred mothers and their respective babies were selected by convenience sampling and were divided equally into intervention and control groups. The tools used for data collection were a questionnaire and an observational checklist. The data were analyzed using Statistical Package for Social Sciences version 17 for descriptive and inferential statistics. Umbilical cord training was effective in enhancing mothers’ knowledge and skills in the intervention group. The result showed that the omphalitis rate was reduced significantly in the intervention group; also the intervention group had a shorter separation time (mean=5.02) compared to the control group (mean=7.24). In conclusion, the application of 4% chlorhexidine on the freshly cut umbilical cord stump, significantly reduces omphalitis rate. This inexpensive and simple intervention can save a significant number of newborn lives in developing countries.
Paulus as vredemaker. Oor die resepsie van die Brief aan Filemon in die vierde en vyfde eeu n.C.
Authors: Tolmie D. Francois
Published: July 2015

Paul, the peacemaker. On the reception of the Letter to Philemon in the 4th and 5th centuries AD. By means of his letter to Philemon Paul attempted to make peace between Philemon and his slave, Onesimus. The theological aspects of this endeavour have been discussed often in academic circles, but thus far little attention has been given to what the practical implications of this would have been for Philemon’s household. In this article, this issue is addressed from a particular perspective, namely how this aspect was interpreted by Christians in the 4th and 5th centuries CE. The interpretations of the Letter to Philemon by Ambrosiaster, Jerome, John Chrysostom, Pelagius, Theodore of Mopsuestia and Theodoret of Cyrus are then investigated systematically in order to determine what their views were in this regard. It is shown that they all agreed that Philemon would (or would have no choice but to) forgive Onesimus, and that Onesimus would have turned into a better slave. All of these interpreters agreed that there would not be any drastic social changes in Philemon’s household although it does seem as if one of them, Ambrosiaster, realised that what Paul expected of Philemon could have had serious consequences for the relationship between Philemon and Onesimus.
Linkage map construction and quantitative trait loci (QTL) mapping using intermated vs. selfed recombinant inbred maize line (Zea maysL.)
Authors: Khanal R. , Navabi A. , Lukens L.
Published: July 2015

Khanal, R., Navabi, A. and Lukens, L. 2015. Linkage map construction and quantitative trait loci (QTL) mapping using intermated vs. selfed recombinant inbred maize line (Zea mays L.). Can. J. Plant Sci. 95: 1133–1144. Intermating of individuals in an F2population increases genetic recombination between markers, which is useful for linkage map construction and quantitative trait loci (QTL) mapping. The objectives of this study were to compare the linkage maps and precision of QTL detection in an intermated recombinant inbred line (IRIL) population and a selfed recombinant inbred line (RIL) population. Both, IRIL and RIL, populations were developed from Zea mays inbred lines CG60 and CG102. The populations were grown in two environments to evaluate traits, and inbred lines from each population were genotyped with SSR and SNP markers for linkage map construction and QTL identification. In addition, we simulated RIL and IRIL populations from two inbred parents to compare the precision of QTL detection between simulated RIL and IRIL populations. In the empirical study, the linkage map was longer in RIL as compared with IRIL, and the average QTL support interval was reduced by 1.37-fold in the IRIL population compared with the RIL population. We detected 16 QTL for flowering time, plant height, leaf number, and stay green in at least one recombinant inbred line population. Two out of 16 QTL were shared between two recombinant inbred line populations. In the simulation study, the QTL support interval was reduced by 1.66-fold in the IRIL population as compared with the RIL population and linked QTL were identified more frequently in IRIL population as compared with RIL population. This study supports the utility of intermated RIL populations for precise QTL mapping.
Pintail general purpose winter wheat
Authors: Salmon D. F. , Helm J. H. , Graf R. J. , Albers S. , Aljarrah M. , Xi K. , Oro M. , Lohr S. , Bergen C.
Published: July 2015

Salmon, D. F., Helm, J. H., Graf, R. J., Albers, S., Aljarrah, M., Xi, K., Oro, M., Lohr, S. and Bergen, C. 2015. Pintail general purpose winter wheat. Can. J. Plant Sci. 95: 1271–1276. Pintail is an awnless hard red winter wheat (Triticum aestivum L.) cultivar that was registered in 2012 and is eligible for grades of Canada Western General Purpose (CWGP) wheat. It was developed using wheat × maize-pollen doubled haploid techniques. Evaluated across western Canada from 2008 to 2010 relative to CDC Harrier, CDC Falcon and CDC Ptarmigan, Pintail expressed grain yield ranging from 98.6 to 105.8% of these CWGP wheat checks. Its area of greatest adaptation was in the parkland and semi-arid prairie regions of Alberta and western Saskatchewan, where cold tolerance is a primary concern. Pintail exhibited excellent winter survival, intermediate maturity, medium height and strong straw. Test weight was within the range of the checks, and kernel weight was lower than all of the checks. Pintail displayed moderate resistance to stripe rust, moderate susceptibility to stem and leaf rust, and susceptibility to common bunt and Fusarium head blight. The high yield and awnless spike of Pintail should make it particularly attractive in various livestock feed and forage applications.
Characterization of Leishmania (Leishmania) waltoni n.sp. (Kinetoplastida: Trypanosomatidae), the Parasite Responsible for Diffuse Cutaneous Leishmaniasis in the Dominican Republic
Authors: Shaw Jeffrey , Pratlong Francine , Floeter-Winter Lucile , Ishikawa Edna , El Baidouri Fouad , Ravel Christophe , Dedet Jean-Pierre
Published: July 2015

Leishmania parasites isolated, between 1979 and 1988 by the late Bryce Walton, from Dominican Republic (DR) patients with diffuse cutaneous leishmaniasis, were characterized using a panel of 12 isoenzymes, 23 monoclonal antibodies, small subunit ribosomal DNA (SSu rDNA), and multilocus sequence analysis (MLSA). The isoenzyme and monoclonal antibody profiles and the MLSA results showed that the Dominican Republic parasites were distinct from other described Leishmania species. This new species belongs to the mexicana complex, which is distributed in central and parts of northern South America. It is suggested that the parasites uniqueness from other members of the mexicana complex is related to it being isolated on an island for millions of years. If Leishmania (Leishmania) waltoni fails to adapt to some imported mammal, such as the house rat, it will be the only Leishmania to be classified as an endangered species. The excessive destruction of habitats on Hispaniola threatens the survival of its vectors and presumed natural reservoirs, such as the rodent hutias and the small insectivorous mammal solenodon. The concept of Leishmania species is discussed in the light of recent evaluations on criteria for defining bacterial species.
Quantification of Human Norovirus GII on Hands of Mothers with Children Under the Age of Five Years in Bagamoyo, Tanzania
Authors: Mattioli Mia Catharine M. , Davis Jennifer , Mrisho Mwifadhi , Boehm Alexandria B.
Published: July 2015

Human noroviruses are the most common cause of viral gastroenteritis worldwide and one of the leading causes of viral diarrhea in children under the age of 5 years. Hands have been shown to play an important role in norovirus transmission. Norovirus outbreaks tend to exhibit strong seasonality, most often occurring during cold, dry months, but recently have also been documented during hot, dry winter months in the southern hemisphere. Other research suggests that rainfall is an important factor in norovirus outbreaks. This study examines the prevalence and concentration of human norovirus GII on the hands of mothers in Bagamoyo, Tanzania, during the rainy and dry seasons. Norovirus GII was detected in approximately 5% of hand rinse samples during both the rainy and dry seasons. Fecal indicator bacteria levels, Escherichia coli and enterococci, in hand rinse samples were not associated with norovirus hand contamination. Turbidity of the hand rinses was found to be associated with norovirus presence on mothers' hands; however, this relationship was only observed during the rainy season. The results suggest mothers' hands serve as a source of norovirus exposure for young children in Tanzanian households, and further work is needed to determine better indicators of norovirus contamination in these environments.
Human and Animal Fecal Contamination of Community Water Sources, Stored Drinking Water and Hands in Rural India Measured with Validated Microbial Source Tracking Assays
Authors: Schriewer Alexander , Odagiri Mitsunori , Wuertz Stefan , Misra Pravas R. , Panigrahi Pinaki , Clasen Thomas , Jenkins Marion W.
Published: July 2015

We examined pathways of exposure to fecal contamination of human and animal origin in 24 villages in Odisha, India. In a cross-sectional study during the monsoon season, fecal exposure via community water sources (N = 123) and in the home (N = 137) was assessed using human- and nonhuman-associated Bacteroidales microbial source tracking (MST) markers and fecal coliforms (FCs). Detection rates and marker concentrations were examined to pinpoint pathways of human fecal exposure in the public and domestic domains of disease transmission in study communities. Human fecal markers were detected much more frequently in the domestic domain (45% of households) than in public domain sources (8% of ponds; 4% of groundwater drinking sources). Animal fecal markers were widely detected in both domains (74% of ponds, 96% of households, 10% of groundwater drinking sources), indicating ubiquitous risks of exposure to animal feces and zoonotic pathogens. This study confirms an often suggested contamination link from hands to stored water in the home in developing countries separately for mothers' and children's hands and both human and animal fecal contamination. In contrast to MST markers, FCs provided a poor metric to assess risks of exposure to fecal contamination of human origin in this rural setting.
Concurrent Pneumonia in Children Under 5 Years of Age Presenting to a Diarrheal Hospital in Dhaka, Bangladesh
Authors: Leung Daniel T. , Das Sumon K. , Malek M. A. , Qadri Firdausi , Faruque A. S. G. , Chisti Mohammod J. , Ryan Edward T.
Published: July 2015

Respiratory and gastrointestinal infections are the top killers of children worldwide, and their co-occurrence is reported but not well understood. Our aim was to determine the risk factors for concurrent presentation of diarrhea and pneumonia (DP) in a resource-limited setting in Bangladesh. We used data from the Diarrheal Disease Surveillance System of the icddr,b Dhaka Hospital to identify children < 60 months of age with diarrhea and concurrent pneumonia, defined as a history of cough, an abnormal lung examination, and tachypnea. For the years 1996–2007, out of total 14,628 diarrheal patients surveyed, there were 607 (4%) patients who satisfied criteria for pneumonia. Those with DP had a higher mortality rate (4% versus 0.05%, odds ratio [OR] = 86, 95% confidence interval [CI] = 26–286) and a longer hospital stay (mean 84 versus 26 hours, difference 58 hours, 95% CI = 52–64 hours) than those with diarrhea (D) only. In multivariable logistic regression comparing cases (N = 607) with controls matched for month and year of admission at a ratio of 1:3 (N = 1,808), we found that DP was associated with younger age, male gender, severe acute malnutrition (SAM), less maternal education, lower family income, and lack of current breast-feeding history.
Two Generations of “Gold Standards”: The Impact of a Decade in Hepatitis E Virus Testing Innovation on Population Seroprevalence
Authors: Kmush Brittany L. , Labrique Alain B. , Dalton Harry R. , Ahmed Zabed B. , Ticehurst John R. , Heaney Christopher D. , Nelson Kenrad E. , Zaman Khalequ
Published: July 2015

Hepatitis E virus (HEV) is a global pathogen responsible for approximately 20 million infections every year in developing countries, yet remains under-recognized. In this population-based cohort study, 1,025 randomly selected participants were enrolled from Matlab, Bangladesh (2004–2005). All participants were tested for HEV antibodies and total immunoglobulin (Ig), using an in-house enzyme immunoassay developed by Walter Reed Army Institute of Research (WRAIR). In 2014, we retested the banked sera of 1,009 of those participants using the Wantai anti-HEV IgG enzyme-linked immunosorbent assay (ELISA). The WRAIR assay estimated the overall population seroprevalence as 26.6% (95% confidence interval [CI]: 24.0, 29.5), whereas the Wantai assay produced significantly higher estimated seroprevalence, 46.7% (95% CI: 43.5–49.8) (P < 0.001). However, the two tests give nearly identical findings in those 5 years and under (N = 94) with a 98% agreement between the tests. Retesting populations with modern assays is necessary to establish better population-level estimates of disease burden.
Commentary on "An intermediate state between the kagome-ice and the fully polarized state in Dy$_2$Ti$_2$O$_7$"
Authors: Perfetti Mauro
Published: July 2015

A Commentary on the paper by S A Grigera et al. [Pap. Phys. 7, 070009 (2015)]. Received: 25 June 2015,  Accepted: 25 June 2015; Edited by: A. Vindigni; DOI: http://dx.doi.org/10.4279/PIP.070010Cite as: M Perfetti, Papers in Physics 7, 070010 (2015)This paper, by M. Perfetti, is licensed under the Creative Commons Attribution License 3.0.
Teaching Lifelong Research Skills in Residency: Implementation and Outcome of a Systematic Review and Meta-Analysis Course
Authors: Himelhoch Seth , Edwards Sarah , Ehrenreich Mark , Luber M. Philip
Published: July 2015

Background

There is rising concern that fundamental scientific principles critical to lifelong learning and scientific literacy are not sufficiently addressed during residency.

Objective

We describe the development, implementation, and evaluation of a systematic review and meta-analysis course designed to improve residents' research literacy.

Intervention

We developed and implemented a novel, interactive, web-enhanced course for third-year psychiatry residents to provide the theoretical and methodological tools for conducting and reporting systematic reviews and meta-analyses. The course is based on Bloom's learning model, and established criteria for reporting systematic reviews and meta-analyses. Eight sequential learning objectives were linked to 8 well-specified assignments, with the objectives designed to build on one another and lead to the creation of a scientific manuscript.

Results

From 2010–2014, 54 third-year psychiatry residents (19 unique groups) successfully completed the course as part of a graduation requirement. The majority rated the course as being good or very good, and participants reported a statistically significant increase in their confidence to conduct systematic reviews (χ2 = 23.3, P < .05) and meta-analyses (Fisher exact test, P < .05). Estimated total dedicated resident and faculty time over a period of 36 weeks was 36 to 72 hours and 60 hours, respectively. Residents' academic productivity included 11 conference presentations and 4 peer-reviewed published manuscripts, with 2 residents who were awarded honors for their projects.

Conclusions

A formal training course in systematic reviews and meta-analyses offers a valuable learning experience, which enhances residents' research skills and academic productivity in a feasible and sustainable approach.
GME Concentrations: A Collaborative Interdisciplinary Approach to Learner-Driven Education
Authors: Nagler Alisa , Chudgar Saumil M. , Rudd Mariah , Whicker Shari A. , Gagliardi Jane P. , Narayan Aditee , Heflin Mitchell T. , Gordon David C. , Andolsek Kathryn M.
Published: July 2015

Background

Graduate medical education (GME) programs may struggle to provide the knowledge, skills, and experiences necessary to meet trainee career interests and goals beyond a clinical focus. Sponsoring institutions can partner with programs to deliver content not included in typical clinical experiences of GME programs.

Objective

To perform a needs assessment and to develop, implement, and measure acceptability and feasibility of an institution-wide GME Concentrations curriculum.

Methods

In response to the needs assessment, GME leadership developed 4 concentrations: (1) Resident-as-Teacher; (2) Patient Safety and Quality Improvement; (3) Law, Ethics, and Health Policy; and (4) Leaders in Medicine. We formed advisory committees that developed curricula for each concentration, including didactics, experiential learning, and individual project mentoring. Participants completed pre- and postassessments. We assessed feasibility and evaluated participant presentations and final projects.

Results

Over the course of 3 years, 91 trainees (of approximately 1000 trainees each year) from 36 GME programs (of 82 accredited programs) have participated in the program. The number of participants has increased each year, and 22 participants have completed the program overall. Cost for each participant is estimated at $500. Participant projects addressed a variety of education and health care areas, including curriculum development, quality improvement, and national needs assessments. Participants reported that their GME Concentrations experience enhanced their training and fostered career interests.

Conclusions

The GME Concentrations program provides a feasible, institutionally based approach for educating trainees in additional interest areas. Institutional resources are leveraged to provide and customize content important to participants' career interests beyond their specialty.
Implementation of a Novel, Resident-Led, Nocturnal Curriculum
Authors: Golbus Jessica R. , Manly David A. , Wonneberger Katherine A. , Hanff Thomas C. , Murphy Kathleen M. , Wang Daniel S. , McKee Steven G. , Bellini Lisa
Published: July 2015

Background

Duty hour restrictions for resident physicians have led to radical changes in graduate medical education, including a shift to more night float rotations. These rotations have been viewed by residents as predominantly service focused with little opportunity for formalized education.

Objective

To develop and deliver a resident-driven, nocturnal curriculum to enhance the educational content and value of night float rotations.

Methods

The Hospital of the University of Pennsylvania is a 695-bed, tertiary care academic medical center. Upper-level internal medicine residents developed and peer-reviewed case-based scripts designed to be delivered in 15- to 20-minute teaching sessions. We evaluated the quality of teaching using anonymous, free-response surveys.

Results

Twenty-four scripts were developed that explored the differential diagnoses, diagnostic pitfalls, and management of clinical problems that interns frequently encounter on night float rotations. Of 83 eligible residents, 45 (54%) responded to the survey. Teaching occurred an average of 4 nights per week and was uniformly viewed as high yield and topical by night float interns.

Conclusions

A resident-driven, nocturnal curriculum was implemented through the use of case-based teaching scripts, allowing for delivery of a standardized curriculum that capitalizes on the teaching opportunities afforded by the night shift. This intervention may serve as a model for nocturnal education in other departments and institutions.
Retrospective Analysis of Etiology, Incidence and Management of Facial Trauma Over 5 Years in North India: A Clinical Audit
Authors: Sharma Rohit , Esht Vandana , Goomer Pallvi
Published: July 2015

Aim

To analyze etiology, incidence and management of facial trauma over a period of 5 years in a tertiary care center in North India.

Materials and methods

Records of 195 patients with 274 facial fractures were analyzed retrospectively from 2009 to 2013. Fractures were classified according to anatomical area involved (zygoma, maxilla, mandible, teeth), and etiology was divided into road traffic accidents (RTAs), falls, sports injuries and assaults. It was found that RTA was most common etiologic factor for facial trauma, followed by falls, assaults and sports injuries. Mandibular fractures were most common, followed by midface fractures and dental injuries. Various treatment options were also evaluated.

Results

Mandibular fractures were more common than midface fractures. Most common line of treatment was open reduction and internal fixation with mini-plate fixation. Mandible reconstruction was done in one case of bone defect following a gun-shot injury. Coronoidectomy had to be performed in one case of zygoma fracture.

Conclusion

Patient's best interest, affordability and general well being should be kept in mind while managing trauma of maxillofacial region. Surgeon should utilize his knowledge to the best possible level as any injury to this region has a direct impact on psyche as well as general well being of patient.

How to cite this article

Sharma R, Esht V, Goomer P. Retrospective Analysis of Etiology, Incidence and Management of Facial Trauma Over 5 Years in North India: A Clinical Audit. J Postgrad Med Edu Res 2015;49(2):59-61.
Hearing Loss with Amphotericin B Therapy in Patients with Rhinocerebral Aspergillosis: Is it a Reality?
Authors: Mohindra Satyawati , Mohindra Sandeep , Gupta Karan , Gupta Bhumika , Singh Dharamveer
Published: July 2015

Context

Study carried out to investigate the relationship of amphotericin B (AmB) therapy with hearing loss developing in patients with rhinocerebral aspergillosis during prolonged AmB therapy.

Aim

To study the effect of prolonged AmB therapy on the hearing acuity of patients suffering from invasive fungal sinusitis. Setting and design: Nonrandomized prospective study carried in Department of Otolaryngology and Head and Neck Surgery from January, 2010 to June, 2013.

Materials and methods

High frequency pure tone audiometry (PTA) and cold caloric test (CCT) were done for all patients before starting of therapy with AmB. Both tests were repeated at 500 mg, 1 and 2 gm of AmB administration. Follow-up was done for all patients at 3 and 6 months after completion of therapy.

Results

Twenty-four patients of invasive fungal sinusitis included. On prolonged AmB therapy some patients had deterioration in hearing. But these changes were not statistically significant. The changes were mild and shift was one grade above or below. It was also seen that the hearing complaints were reported in the middle of the therapy although all these patients had baseline hearing loss.

Conclusion

Amphotericin B does cause some change in hearing pattern; although not statistically significant. A further study is required with more number of patients so as to say definitively that AmB causes a change in hearing. Though these patients have numerous factors which can affect hearing in many ways, a systematic study is required to go a long way in clearing the doubts attached to AmB therapy.

Key message

Amphotericin related hearing loss has not been reported in English literature till date. Our study focuses on the effect of AmB on hearing. Amphotericin B does cause some change in hearing pattern, although not statistically significant. All the patients complained of hearing deterioration while some showed improvement on audiogram (though not significant) showing a paradoxical feature.

How to cite this article

Mohindra S, Gupta B, Mohindra S, Gupta K, Singh D. Hearing Loss with Amphotericin B Therapy in Patients with Rhinocerebral Aspergillosis: Is it a Reality? J Postgrad Med Edu Res 2015;49(2):66-69.