bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral Optimization of Fan Rotation Noise Based on Vector Composition Method
Authors: Wang Yuan Wen , Dong Da Wei , Xie Xiao , Yan Bing , Sun Yu Hua
Published: September 2013

In order to optimize the rotation noise spectrum of vehicle alternator cooling fan, a Vector Composition Method was proposed. Based on this method, the relative sound pressure level (RSPL) variations were calculated, which were then used as parameters in the optimization of spectral structure. In this article, the sound pressure level (SPL) variations of the 12thand 18thorder (of rotation frequency) who had the most prominent fan rotation noises were set as optimization targets, the blade distribution angles were optimized to ameliorate the spectral structure and the distribution of spectral energy. Calculations showed that, the RSPL in orders 12 and 18 were decreased by 9.3dBA and 10.5dBA respectively, comparing with experiment results, the errors were 3.9% and 4.11% respectively. Results suggested that the rotation noise of target orders had been significantly diminished, so the objective of optimizing spectral structure was reached. This method has a guiding significance to the design of blade distribution angles.
The Research of Chaos Time Series on Chatter Signal Recognition
Authors: Jiang Yong Xiang , Du Bing , Zhang Pan , Deng San Peng , Qi Yu Ming
Published: September 2013

The online detecting of chatter is the key technology to improve the machining quality. Based on the nonlinear chaos control theory in discrete dynamic system, the processing vibration signal discrete time series is taken as system nonlinear input, the C-C algorithm and correlation integral was used to determine appropriate embedding dim m and time delay τ. Then the phase space is reconstructed by discrete vibration signal. In milling chatters experiment, the time series analysis method is used to get the phase diagram before and after chatter. The chatter phase chart shows the characteristics of chaos and recognized the milling chatter.
Correction of Low Frequency Component in Spectrum Analysis Based on Hilbert Transform
Authors: Wang Jun Jie , Xie Zhi Jiang , Chen Ping
Published: September 2013

Because of the serious interference coming from the negative frequency in low frequency correction, the traditional correction methods no longer work. This paper proposes an improved ratio method to correct the frequency, phase and amplitude of spectrum peak when the spectral line locates near the left end in spectrum. The Hilbert Transform is used to diminish the impact of interference of the mirror frequency. The barycenter of two spectral lines is used to obtain the correcting value. A new formula is developed when the frequency is less than the frequency resolution. One of the spectral lines is located in the main lobe and the other is in the first side lobe. Furthermore, the direct current has nearly no impact on this new method theoretically which is a key problem in low frequency correction. The simulation shows that the frequency, phase and amplitude of a theoretical low frequency can be corrected satisfactorily. The result of the correction improves a lot compared with the traditional method. However, this method could not correct the spectrum with multiple components of low frequency.
The Design of the Drive System of the Crank Underdrive Quick Presses
Authors: Xiao Mao Hua , Yang Fei , Ke Zun Mang , Zhu Si Hong , Xiao Deng Song
Published: September 2013

Based on production needs, a main transmission mechanism of underdrive speed press was designed in this paper. The design of the main transmission mechanism is the improvements and alternative of sine institutions slider-crank mechanism made. Underdrive and dual slider mechanism were designed, in order to achieve the presses punching process. The nominal pressure angle and the nominal torque were calculated. A preliminary calculation and design of the crankshaft, bearings, slider of the main drive mechanism. Ensure reliable operation and to provide a basis for the optimization design.
The Ultrasonic Honing of Amplitude Transformer's Optimal Design Based on VB Platform
Authors: Wen Yi Fang , Chen Xin , Zhang Feng Nian
Published: September 2013

Based on VB, start from the performance requirements of ultrasonic honing for the amplitude transformer, and derive the amplitude transformer wave equation and boundary conditions. Then, establish a resonance frequency equation, programming iterating the critical size of the Amplitude transformer. To get the optimal solution, verified the results of optimal design by experiment. Experiments show that the optimal design is feasible, fast and accurate, possess of great practical value. It has played a prominent effect for further optimal design and processing applications of ultrasonic honing.
Research on the Teaching Numerical Lathe Machine Based on Mach3
Authors: Wang Ying Jie , Zhao Wei , Wang Zhi Ping
Published: September 2013

According to the demands of teaching, it is designed and manufactured that a new visual model of CNC turning lathe with assembles the horizontal bed and inclined bed in one. As it can display the structure of CNC lathe directly and intuitively, the model can be used for the teaching of CNC courses. The model has micro-switch, which can be used to control the movement of the workplace, and the automatic feed strokes of the tool, thus avoiding the collisions during manufacturing. Meanwhile, the test proved that it can cut the nylon, wood, engineering plastics and so on, so this model can satisfy the demands of teaching.
Rotary Combined Ultrasonic and Electrochemical Machining Device of Small Holes and its Test Study
Authors: Liu Ze Xiang , Kang Min , Fu Xiu Qing
Published: September 2013

Discussing the technology of small holes processing and the development of the combined ultrasonic and electrochemical machining, the technology of combined ultrasonic and electrochemical Machining was studied and its device was designed. By the preliminary tests, the impacts of various factors on the processing of small holes by combined ultrasonic and electrochemical machining were analyzed and some problems were found, which provided a basis for the future research.
Fatigue Cracking Processes of a Thick-Walled Component of a Chemical Pipeline
Authors: Cieśla Marek , Mutwil Kazimierz
Published: September 2013

At present, there are no generally accepted and widely recognized procedures to determine condition of material of devices subject to complex long-term thermo-mechanical loads. Condition of pipeline material usually changes when subjected to the conditions of long-term operation. Its structure changes and, consequently, so do its mechanical properties, including fatigue characteristics and crack resistance. Therefore, the durability of a component operating under thermal and mechanical loads cannot be discussed separately from its current material properties. This applies in particular to changes that take place in the material micro-structure and to their connection with mechanical properties. This paper covers analyses of stress in the material of a selected pipeline component – pipe tee that is used in chemical plants. Thermo-mechanical interactions determining stress distribution in the component have been taken into account in the calculations. Morphology and location of the cracks indicated that a fatigue-like nature of impacts was the cause of material destruction. Loads of this type occur mainly in conditions of start-up and shut-down. For these reasons, condition of the material in the above-mentioned unstable conditions was subjected to numerical stress analysis. Due to geometric complexity of the pipeline, the distribution of stress in the T-pipe was calculated in two stages: the object was modeled from a global and local perspective. The resulting stress distributions helped to determine factors affecting durability of the tested object. Metallurgy tests were also conducted in order to ascertain factors determining the degradation of material structure and processes of crack formation and development. As a result of research one ascertained that the process of T-pipe cracking under operating conditions was a combined effect of thermo-mechanical and chemical actions determined by the course of intercrystalline corrosion. Synergic interaction of corrosion processes and variable thermal and mechanical loads caused nucleation and propagation of cracks. The crack systems in T-pipe areas subject to the highest stress showed courses characteristic for thermal fatigue of material. The results obtained will identify degradation mechanism of materials used in chemical installations.
A Description of Local Material Properties Close to a Butt Weld
Authors: Hutař Pavel , Ševčík Martin , Lach Ralf , Knésl Zdeněk , Náhlík Luboš , Grellman Wolfgang
Published: September 2013

The paper presents a methodology for the lifetime assessment of welded polymer pipes. A fracture mechanics analysis of a butt-welded joint is performed by simulating radial crack growth in the nonhomogenous region of the pipe weld. It was found that the presence of material nonhomogeneity in the pipe weld caused by the welding procedure leads to an increase in the stress intensity factor of the radial crack and changes the usual failure mode of the pipe system. This can lead to a significant reduction in the lifetime of the pipe system.
Creep Modified Structural Relaxation of Fe-Based Amorphous Alloy
Authors: Juríková Alena , Csach Kornel , Miškuf Jozef
Published: September 2013

Structural relaxation an creep strain recovery of the amorphous metallic glass Fe40Ni41B19 after the longtime loading at different annealing temperatures below the glass transition temperature have been studied using anisothermal differential scanning calorimetry (DSC) and dilatometry (TMA). It has been demonstrated that structural relaxation effects depend on the stress-annealing temperature of the amorphous ribbon. The influence of the stress-annealing temperature on the rearrangement of deformation defects in the amorphous alloy Fe-Ni-B was analyzed. The properties of local disordering in flow defects were analyzed by means of their activation energy spectra. In the samples stress-annealed at higher temperatures, only the relaxation centers favourably oriented to the external stress contribute to the creep strain recovery process.
Effect of Welding Parameters on the Quality of Spot Welds Combining AHSS Steel and HSLA Steel
Authors: Kaščák Ľuboš , Spišák Emil
Published: September 2013

The resistance spot welding of dissimilar materials is generally more challenging than that of similar materials due to differences in the physical, chemical and mechanical properties of the base metals. Advanced high strength steels and high strength low alloy steels are utilized in automotive industry to reduce weight of the vehicle body and consequently lowering the fuel consumption to achieve the lowest possible fuel consumption, high active and passive safety of passengers while decreasing the amount of emission. The influence of the primary welding parameters, especially welding current, microhardness and tensile shear load bearing capacity of dissimilar welds between TRIP 40/70 as an Advanced High Strength Steel and H220PD as a High-Strength Low-Alloy steel has been investigated in this paper.
Material Testing of Natural Stones Used in Historical Buildings Based on Scanning Electron Microscopy and Nanoindentation
Authors: Koudelka Petr , Kytýř Daniel , Koudelková Veronika , Lukeš Jaroslav , Doktor Tomáš , Valach Jaroslav
Published: September 2013

In the case of material parameters required for evaluation of built heritage preservation state, knowledge of the least possible volume of removed sample is essential in order to minimize damage accumulation to the buildings. These requirements lead to determination of representative volume element (RVE) that was in this paper calculated using combination of image and signal processing techniques. Then, a detailed map of material properties was created using nanoindentation to evaluate local characteristics of the material. Furthermore, atomic composition of samples was quantified by energy dispersive spectrometry (EDX) detector for scanning electron microscopy (SEM) device. Presented method based on combination of SEM, EDX and nanoindentation techniques demonstrates possibility of effective testing in the field of historical buildings preservation.
On the Indentation Modulus of Sintered Materials
Authors: Kupková Miriam , Kupka Martin
Published: September 2013

When the depth-sensing (nano)indentation is applied to sintered samples, measured properties, which are expected to represent the material of an individual grain, seem to depend on the overall porosity of the macroscopic sample. To understand such a result, it is assumed that while the nanoindenter penetrates into the surface grain and probes the properties of its material, the grain itself serves as another, larger indenter indenting the rest of sample and probing the properties that represent the bulk of material rather than individual grains. Load vs. displacement curve reflects the synergetic response of these two “indenters” and so it contains information about the sample’s mechanical properties at both microscopic and macroscopic scales. Obtained theoretical results agree qualitatively with the experimental data (the dependence of the indentation modulus on the porosity of sample; the indentation size effect).
Efect of Cyclic Heat Treatment on Cast Structure of TiAl Alloy
Authors: Petrenec Martin , Vraspírová Eva , Němec Karel , Heczko Milan
Published: September 2013

The subject of the article is focused on the refining of the cast structure of gamma TiAl–2Nb alloy using cyclic heat treatment and on the analysis of the grain refining mechanism. Microstructure evolution after applied cycles of heat treatment was characterized using light, laser and electron microscopy and using microhardness tests. Application of five heat treatment cycles during which two phase transformations (eutectoid and alfa-recrystallization reactions) repeatedly took place resulted αin refining of the cast columnar structure. The mean grain-lamellar colony size 0.512 mm was transformed to fully lamellar structure containing gamma and alfa2 phases having the mean grain size 0.229 mm. Lamellae thickness of gamma was not changed while the thickness of alfa2 phase decreased to 78 nm. Refining of alfa2 phase resulted in the increase of the microhardness by 20 %. The recrystallized cast structure obtained by cyclic heat treatment and the knowledge on the mechanisms of the refining the structure were compared and discussed with the literature data.
Local Changes of Microhardness in Dissimilar Weld Joints after High Temperature Exposure
Authors: Sohaj Pavel , Jan Vít
Published: September 2013

The paper presents results obtained during evaluation of dissimilar weld joints of creep-resistant steels. During high temperature exposure of dissimilar weld joints, alloying elements were redistributed across the weld interface. These diffusion effects can cause local changes of microstructure and have a direct effect on local mechanical properties in weld interface area. Carbon and nitrogen have the strongest influence on changes of mechanical properties of steels. . These local changes of mechanical properties have a strong influence on the reliability and the service live of the whole welded structures. The dissimilar joints of the austenitic steel/martenzitic steel type was studied. Laboratory weld joints were prepared and annealed at different temperatures for different time periods. Microhardness profiles across the weld interface were measured and the influence of long-term, high temperature exposure on the changes of local microhardness was evaluated. Results were compared with pseudo-binary phase diagrams and with the literature.
Mechanical Properties of Single and Double-Layered PVA Nanofibers
Authors: Tesárek Pavel , Ryparová Pavla , Rácová Zuzana , Králík Vlastimil , Němeček Jiří , Kromka Alexander , Nežerka Václav
Published: September 2013

Multi-layered nanofiber textiles can be utilized in many applications. In such case the individual layers are laid in more stages and the question arises whether the connection is perfect. Two kinds of samples of PVA nanotextiles having the weight of 1.3 g/m2 (single-layered, AI) and 2.8 g/m2 (double-layered, AII), respectively. It was shown that mechanical properties, in particular the average tensile strength (24 N/mm for AI and 51 N/mm for AII) and stiffness (950 N/mm for AI and 1600 N/mm for AII), are independent of the number of layers, only their weight per unit area matters. This indicates that the bond between the individual layers is perfect.
Indentation Size Effects in Ductile and Brittle Materials
Authors: Menčík Jaroslav , Elstner Martin
Published: September 2013

Indentation hardness of homogeneous materials should be constant. However, at very small depths, the apparent hardness often increases with decreasing imprint size. The paper discusses various cases of this indentation size effect in metals and ceramics and explains the extrinsic and intrinsic reasons.
Mechanical Properties of Aluminum Alloys by Instrumented Indentation: Case Study on Almigo Hard
Authors: Nohava Jiri , Haušild Petr , Axelson David Gichangi , Bolloré Gwenaél
Published: September 2013

This paper presents a case study of instrumented indentation for assessment of mechanical properties of a specific Almigo Hard aluminium alloy. It shows that conventional microhardness is not suitable for local testing of this material and that instrumented indentation can reveal significantly more information about the tested material such as Young’s modulus and elastic-plastic characteristics. The study compares mechanical and elastic-plastic properties of the Almigo Hard, aircraft Al alloy and reactor vessel ferritic steel by single peak load and cyclic indentations in order to demonstrate superior properties of the Almigo Hard alloy.
Failure Initiation in Dual-Phase Steel
Authors: Ramazani Ali , Schwedt Alexander , Aretz Anke , Prahl Ulrich
Published: September 2013

This research work aims to model the failure initiation in dual-phase (DP) steel. A microstructure based approach by means of representative volume elements (RVE) is employed to evaluate the microstructure deformation and the failure initiation on the mesoscale. In order to determine cohesive parameters for martensite cracking, a two level approach has been performed experimentally. First, in-situ bending test in SEM with EBSD measurements before and after the test showed that the crack initiation occurs in martensite islands. Then, mini tensile tests with DIC technique were carried out to identify macroscopic failure initiation strain values. RVE modeling combined with extended finite element method (XFEM) was utilized to model martensite cracking on mesoscale. The identified parameters were validated by comparing the predictions with the experimental results.
Design and Verification of Sandwich Structures for High Speed Trains
Authors: Rusnáková Soňa , Žaludek Milan , Fojtl Ladislav , Rusnák Vladimír
Published: September 2013

Sandwich construction is a composite material structure combining low weight, high strength and good dynamic properties. Typically a sandwich composite consists of three main parts: two thin, stiff and strong facing layers separated by a thick, light and weaker inner core. The faces are adhesively bonded to the core to obtain a load transfer between the components. By this way the properties of each separate component is utilized to the structural advantage of the whole assembly leading to a very high stiffness-to-weight and high bending strength-to-weight ratio. As a result sandwich components achieve the same structural performance as conventional materials with less weight. The material characterization described in the paper is aimed at the structural design of the end cub for a high speed train made of composite sandwich materials. A sandwich structure was considered, made of glass fibber polyester face sheets with a polymeric foam core. Initially, the material properties and the rate sensitivity of the skin and core materials were investigated through a series of static and quasi-static tests. Static and dynamic impact tests were then run on the sandwich structure. For all materials tested, no significant strain-rate effects were observed over the range of test conditions investigated in the study. Results show that the structural response of the sandwich depends primarily on the strength properties of the foam core material. Sandwich peel test is intended for determining the comparative peel resistance of adhesive bonds between facing and cores of sandwich constructions tested under specified test conditions. One method, the climbing drum peel method, is most applicable when the peeled facings are relatively thin, but it can not be applicable in tested composite structures. Peel resistance was tested by modified experimental setup.
Change in Mechanical Properties of Weld Claddings after Cyclic Thermal Loading
Authors: Brezinová Janette , Guzanová Anna , Balog Peter , Viňáš Ján
Published: September 2013

This contribution deals with the analysis of the renovation layer quality of continuous casting steel rollers, developed through the submerged arc surfacing method (SAW). The continuous casting roller was analysed through the degradation phenomena which act during the operation. Four kinds of filler materials were used for the renovation of the worn roller. Surfacing was carried out as a three-layer in order to eliminate the need for intermediate layer formation. The quality of weld deposits was evaluated in terms of the structure and microhardness after thermal cyclic loading. The best properties showed newly developed filler material W8-WLDC8 from point of view of the microhardness.
Dung beetles (Coleoptera: Scarabaeidae) associated with cattle dung on native grasslands of southern Alberta, Canada
Authors: Floate K.D. , Kadiri N.
Published: September 2013

Surveys of dung beetles establish the dominance of exotic taxa associated with cattle dung on native grasslands in southern Alberta, Canada. Of the 12 species recovered, eight were of European origin and comprised 92.2% of the total catch of 187 963 beetles. Most common wereChilothorax distinctus(Müller),Onthophagus nuchicornis(Linnaeus), andColobopterus erraticus(Linnaeus) (Coleoptera: Scarabaeidae). The abundance ofC. distinctushas been known in the region since the 1920s, whereas that ofO. nuchicornisonly was first reported in the 1990s. The abundance ofC. erraticushas not previously been observed in the region and identifies the species as the newest addition to the endemic fauna. The diversity of native species on pastures in southern Canada and adjacent states is depauperate, such that the establishment of European taxa has appreciably increased levels of bioturbation in pasture ecosystems. The success of these exotic species on northern pastures may reflect a level of cold-tolerance greater than that of most native species.
BACTERIAL PROFILE, ANTIBIOTIC SENSITIVITY AND RESISTANCE OF LOWER RESPIRATORY TRACT INFECTIONS IN UPPER EGYPT
Authors: Agmy Gamal , Mohamed Sherif , Gad Yaser , Farghally Essam , Mohammedin Hamdy , Rashed Hebba
Published: September 2013

BACKGROUND: Lower respiratory tract infections (LRTI) account for a considerable proportion of morbidity and antibiotic use. We aimed to identify the causative bacteria, antibiotic sensitivity and resistance of hospitalized adult patients due to LRTI in Upper Egypt. METHODS: A multicentre prospective study was performed at 3 University Hospitals for 3 years. Samples included sputum or bronchoalveolar lavage (BAL) for staining and culture, and serum for serology. Samples were cultured on 3 bacteriological media (Nutrient, Chocolate ,MacConkey's agars).Colonies were identified via MicroScan WalkAway-96. Pneumoslide IgM kit was used for detection of atypical pathogens via indirect immunofluorescent assay. RESULTS: The predominant isolates in 360 patients with CAP were S.pneumoniae (36%), C. pneumoniae (18%), and M. pneumoniae (12%). A higher sensitivity was recorded for moxifloxacin, levofloxacin, macrolides, and cefepime. A higher of resistance was recorded for doxycycline, cephalosporins, and β-lactam-β-lactamase inhibitors. The predominant isolates in 318 patients with HAP were, methicillin-resistant Staphylococcus aureus; MRSA (23%), K. pneumoniae (14%), and polymicrobial in 12%. A higher sensitivity was recorded for vancomycin, ciprofloxacin, and moxifloxacin. Very high resistance was recorded for β-lactam-β-lactamase inhibitors and cephalosporins. The predominant organisms in 376 patients with acute exacerbation of chronic obstructive pulmonary diseases (AECOPD) were H. influnzae (30%), S. pneumoniae (25%), and M. catarrhalis(18%). A higher sensitivity was recorded for moxifloxacin, macrolides and cefepime. A higher rate of resistance was recorded for aminoglycosides and cephalosporinsCONCLUSIONS: The most predominant bacteria for CAP in Upper Egypt are S. pneumoniae and atypical organisms, while that for HAP are MRSA and Gram negative bacteria. For acute exacerbation of COPD,H.influnzae was the commonest organism. Respiratory quinolones, macrolides, and cefepime are the most efficient antibiotics in treatment of LRTI in our locality.
PROTEOLYTIC PROCESSING OF VON WILLEBRAND FACTOR BY ADAMTS13 AND LEUKOCYTE PROTEASES
Authors: Lancellotti Stefano , Basso Maria , De Cristofaro Raimondo
Published: September 2013

ADAMTS13 is a 190 kDa zinc protease encoded by a gene located on chromosome 9q34.   This protease specifically hydrolyzes von Willebrand factor (VWF) multimers, thus causing VWF size reduction. ADAMTS13 belongs to the A Disintegrin And Metalloprotease with ThromboSpondin type 1 repeats (ADAMTS) family, involved in proteolytic processing of many matrix proteins. ADAMTS13 consists of numerous domains including a metalloprotease domain, a disintegrin domain, several thrombospondin type 1 (TSP1) repeats, a cysteine-rich domain, a spacer domain and 2 CUB (Complement c1r/c1s, sea Urchin epidermal growth factor, and Bone morphogenetic protein) domains. ADAMTS13 cleaves a single peptide bond (Tyr1605-Met1606) in the central A2 domain of the VWF molecule. This proteolytic cleavage is essential to reduce the size of ultra-large VWF polymers, which, when exposed to high shear stress in the microcirculation, are prone to form with platelets clumps, which cause severe syndromes called thrombotic microangiopathies (TMAs). In this review, we a) discuss the current knowledge of structure-function aspects of ADAMTS13 and its involvement in the pathogenesis of TMAs, b) address the recent findings concerning proteolytic processing of VWF multimers by different proteases, such as the leukocyte-derived serine and metallo-proteases and c) indicate the direction of future investigations
PREVALENCE OF HPV HIGH-RISK GENOTYPES IN THREE COHORTS OF WOMEN IN OUAGADOUGOU (BURKINA FASO)
Authors: Zohoncon Theodora M. , Simpore Jacques
Published: September 2013

The development of cervical cancer is ​​associated with high-risk Human papilloma viruses (HPV-HR). In sub-Saharan Africa cervical cancer is the most common cancer among women and the leading cause of death attributed to malignant tumors. This study aims to identify HPV genotypes within the 30'S and 50'S HPV families found in two previous studies from our laboratory, and to determine the prevalence of twelve HPV-HR genotypes in a population of women in Ouagadougou. The twelve HPV-HR genotypes were determined by real-time multiplex PCR, in 180 samples from the general population and among a group of HIV-1 infected women. The most common genotypes found were HPV 35 (29.4%) and HPV 31 (26.1%) of the 30’S family, and HPV 52 (29.4%) and HPV 58 (20.6%) of the 50'S family. Multiple infections of HPV-HR were observed in 78.03% of infected women. The frequencies of HPV genotypes from the 30'S and 50'S families were higher, while the genotypes HPV-16 and18 were lower among the women in our study.
Management and Protection of Coastal Area, the Importance of Coastal Processes during the Planning Phase
Authors: Barbaro Giuseppe
Published: September 2013

Coastal processes should be one of the main issues in coastal zone management; ignoring it could lead to wrong decisions which, in turn, could lead to environmental disaster. This letter shows some examples of coastal structures that are built without taking into account coastal processes, and discusses their impact on the environment, with the hopes that the examples provided can serve as a warning for any future decisions. The analyzed zone is the coast of the Calabria Region in southern Italy. The coast is being studied as part of an agreement between the Mediterranea University of Reggio Calabria and the Calabria Basin Authority, concerning the redaction of the Coastal Erosion Risk Mitigation Plan. All data and results are obtained from a preliminary study of the coastal processes in Calabria. Calabria, with more than 700 km of coasts, is affected by coastal erosion, so the proper management and protection of the coastal zone represents an important issue that cannot be avoided.
Live Birth from Previously Vitrified Oocytes, after Trophectoderm Biopsy, Revitrification, and Transfer of a Euploid Blastocyst
Authors: Grifo Jamie A. , Hodes-Wertz Brooke , Lee Hsiao Ling , Ampeloquio Esmeralda , Clarke-Williams Melicia , Adler Alexis , Munné Santiago , Berkeley Alan S.
Published: September 2013

Our objective is to describe a successful live birth from oocyte vitrification followed by thaw, fertilization, blastocyst culture, trophectoderm biopsy, vitrification, and subsequent thaw. Fifteen mature oocytes were frozen from a patient with uterine factor infertility. Thirteen oocytes survived the thaw, and five underwent trophectoderm biopsy and were refrozen. Three euploid embryos were obtained. A single euploid embryo was transferred in the second thaw cycle to a known recipient leading to the delivery of a normal male infant. This case report is proof of the concept that preimplantation screening and diagnosis is an option for fertility preservation patients.
The Challenges of Publishing on Health Informatics in Developing Countries
Authors: Paton C. , Malik M. , Househ M.
Published: September 2013

The Journal of Health Informatics in Developing Countries was established to meet a perceived need for Health Informaticians in developing countries to be able to share the results of their research in an affordable and easy-to-access online publication. The journal was developed using the open source platform “Open Journal System,” and has now published 67 articles across 13 issues. A collaborative editorial approach has been established to address the problems of limited research budgets, difficulties with translating to English and other problems specific to authors from developing countries. The journal faces many challenges including ensuring future financial sustainability and inclusion in journal indexing systems. However, the continuing support of an international body of Associate Editors and Editorial Board Members has enabled a wide range of useful and informative health informatics research to be disseminated across the developing world.
Changes in Vertical Dimension of Complete Dentures due to Rebasing with Different Techniques
Authors: Mohammed Shammas , Alla Rama Krishna , Devarhubli Achut , Shakeel SK
Published: September 2013

Dental literature is devoid of information in respect of altered incisal pin relation due to compression molding in a single denture. It is to be reckoned that in rebasing technique, the entire segment of teeth remain fixed through a matrix of set polymethylmethacrylate that binds all the teeth. Thus, the artificial teeth do not remain as individual but act as a single unified unit of all the teeth. In view of lack of information in change in vertical dimension due to rebasing procedures and with the aim of determining the method of rebasing that result in minimal changes in occlusal discrepancy, the study was undertaken to evaluate the changes in vertical dimension of occlusion after rebasing using two different methods.

How to cite this article

Mohammed S, Alla RK, Devarhubli A, Shakeel SK. Changes in Vertical Dimension of Complete Dentures due to Rebasing with Different Techniques. World J Dent 2013;4(2):96-99.
Microleakage: Apical Seal vs Coronal Seal
Authors: Amlani Harsh
Published: September 2013

Microorganisms can reach the dental pulp through the open cavity, dentinal tubules, gingival sulcus, periodontal ligament through a broken occlusal seal or faulty restoration of tooth previously treated by endodontic therapy or extension of a periapical infection from adjacent infected teeth. During operative procedures, these possible paths must be considered to prevent ingress. While endodontic therapy is being performed, these paths must be blocked to avoid contamination during and after the treatment. Well treated tooth might also fail if microorganisms reach the periradicular tissues. After root canal obliteration, care must be taken to ensure maintenance of the coronal as well as apical seal from contaminants.

How to cite this article

Amlani H, Hegde V. Microleakage: Apical Seal vs Coronal Seal. World J Dent 2013;4(2):113-116.
Craniofacial Anomalies: A Proactive Approach for the Dental Practitioner
Authors: Umasankar K , Jawaharlal Nagalakshmi
Published: September 2013

Congenital malformations have seen a steep increase over recent years. Facial defects too have increased five-fold as a consequence. As dentists grapple with treating such defects, a simple model for prenatal identification of potential risks and counseling coupled with referral and a communication model is presented. With no start-up costs and zero investment in terms of money, such sensitization is expected to be the platform for reduction in congenital facial defects due to education and optimized treatment. Teledentistry, internet and clinical research are cited as tools for effective reduction in birth defects.

How to cite this article

Jawaharlal N, Umasankar K. Craniofacial Anomalies: A Proactive Approach for the Dental Practitioner. World J Dent 2013;4(2):126-130.
Noninvasive Management of Rhesus Alloimmunization
Authors: Agarwal Nirmala , Balani Sweta , Arya Subhash , Puri Ratna Dua
Published: September 2013

Rhesus alloimmunization causes fetal hemolysis, anemia and hydrops leading to stillbirth, neonatal morbidity or mortality. We describe successful management of two cases of Rh alloimmunization with high anti-D titers, by the ultrasound Doppler measurement of their peak systolic velocity in the middle cerebral artery (PSV-MCA) and multiple maternal administrations of intravenous immunoglobulin (IVIg).

How to cite this article

Agarwal N, Balani S, Arya S, Puri RD. Noninvasive Management of Rhesus Alloimmunization. Int J Infertility Fetal Med 2013;4(2):59-61.
Live Birth following Single Embryo Transfer derived from Vitrified Oocyte and Surgically Retrieved Frozen Sperm in a Poor Responder Patient
Authors: Kottur Anu , Kaur Mandeep , Deepika K , Kamath Anuja
Published: September 2013

We report a live birth following transfer of a single embryo derived from vitrified and thawed oocyte in a 30-year-old poor responder patient. Intracytoplasmic sperm injection was done with frozen thawed sperm obtained surgically, as the male partner was suffering from anejaculation and was a poor candidate for other non-surgical methods in view of his medical comorbidities.

How to cite this article

Kaur M, Mittal M, Kamath A, Deepika K, Kottur A, Rao KA. Live Birth following Single Embryo Transfer derived from Vitrified Oocyte and Surgically Retrieved Frozen Sperm in a Poor Responder Patient. Int J Infertility Fetal Med 2013;4(2):62-65.
Effect of Trichloroacetic Acid Hydrogel on Self-Etch Adhesive Bond Strength to Dental Tissues
Authors: Khoroushi Maryam , Fathpour Kamyar
Published: September 2013

Introduction

Trichloroacetic acid (TCA) is a soft tissue cauterizing agent applied to gingival margins prior to cervical tooth-colored restorations. The presentin vitrostudy evaluated the effects of two different concentrations of TCA hydrogel as a hemostatic/preconditioning agent on the shear bond strength (SBS) of a self-etch adhesive to tooth structures.

Materials and methods

Thirty-six flat enamel and 36 flat dentin surfaces were prepared using human molars; each group was subdivided into three subgroups (n = 12). The groups were made ready as follows: In groups 1 (E1 and D1), the enamel (E) and dentin (D) surfaces were designated as control groups and remained intact. In groups 2 (E2 and D2), 35% TCA gel was applied to enamel and dentin surfaces for 30 seconds. In groups 3 (E3 and D3), 50% TCA gel was applied to enamel and dentin surfaces for 30 seconds. Clearfil SE Bond and Z100 composite resin were applied to the surfaces according to manufacturers¡¦ instructions. After 24 hours of incubation and thermocycling, the composite cylinders underwent an SBS test in a DARTEC test machine. Data were analyzed using the ANOVA and Scheffé's test (α = 0.05).

Results

The mean SBS ± SD in the study groups were 34.73 ± 5.66, 35.32 ± 7.3, 23.75 ± 9.67, 20.94 ± 9.84, 19.32 ± 6.20, 23.50 ± 6.63 MPa in the E1, E2, E3, D1, D2 and D3 groups, respectively. ANOVA revealed significant differences between the SBS values of enamel groups (p = 0.001). There were no significant differences between the dentin groups (p = 0.425).

Conclusion

Application of 35 and 50% concentrations of TCA to dentin had no detrimental effect on the bond produced by two-step self-etch adhesive under study; however, application of only 35% TCA to enamel did not result in a detrimental effect on the same adhesive.

How to cite this article

Fathpour K, Khoroushi M. Effect of Trichloroacetic Acid Hydrogel on Self-Etch Adhesive Bond Strength to Dental Tissues. J Contemp Dent Pract 2013; 14(3):375-380.
A Double Blind Study on the Efficacy of Local Application of Hemocoagulase Solution in Wound Healing
Authors: Aslam Sachin , Francis PG , Rao BHS , Ummar M , Issac JK , Nair RB
Published: September 2013

Aim

The present double blind study has been designed to evaluate the efficacy of local application of hemocoagulase solution as compared to a placebo in wound healing following dental extraction.

Materials and methods

A total of 20 patients who required dental extraction for orthodontic intervention were included. The hemocoagulase solution and a placebo were locally applied to the extraction sockets and the efficacy of the solution in terms of bleeding control, anti-inflammatory responses, its antiseptic properties and efficacy in wound healing were evaluated.

Results

The mean time required to achieve hemostasis was found to be 1.37 minutes in side A (test) and 2.33 minutes in side B (control) indicating that side A achieved faster hemostasis when compared to side B. At the 6th hour postoperatively, bleeding was not evident on either sides, and the amount of pain in side A was found to be less compared to side B. The number of RBCs, polymorphs, chronic inflammatory cells were not different in both the groups, whereas at 3rd postoperative day epithelial cells were greater in side A (test) compared to side B (control). Biopsy reports on the 12th postoperative day indicated that the number of fibroblasts, epithelial cells, collagen count was found to be greater in side A (test) compared to side B (control).

Conclusion

The topical hemocoagulase solution may be advocated in the field of oral and maxillofacial surgery, as a hemostatic agent and promoter of wound healing. However, further studies, with large number of cases and different clinical situations should be considered to authenticate the efficacy of this hemocoagulase solution in the practice of oral and maxillofacial surgery.

Clinical significance

Wound healing plays an important role in the success of any surgical procedure, such as extractions, and the hemocoagulase system may act as a hemostatic agent and a promoter of wound healing.

How to cite this article

Aslam S, Francis PG, Rao BHS, Ummar M, Issac JK, Nair RB. A Double Blind Study on the Efficacy of Local Application of Hemocoagulase Solution in Wound Healing. J Contemp Dent Pract 2013;14(3):394-400.
Relationship between Amazon biomass burning aerosols and rainfall over La Plata Basin
Authors: Camponogara G. , Silva Dias M. A. F. , Carrió G. G.
Published: September 2013

Abstract. High aerosol loads are discharged into the atmosphere by biomass burning in Amazon and Central Brazil during the dry season. These particles can interact with clouds as cloud condensation nuclei (CCN) changing cloud microphysics and radiative properties and, thereby, affecting the radiative budget of the region. Furthermore, the biomass burning aerosols can be transported by the low level jet (LLJ) to La Plata Basin where many mesoscale convective systems (MCS) are observed during spring and summer. This work proposes to investigate whether the aerosols from biomass burning may affect the MCS in terms of rainfall over La Plata Basin during spring. Since the aerosol effect is very difficult to isolate because convective clouds are very sensitive to small environment disturbances, detailed analyses using different techniques are used. The binplot, 2D histograms and combined empirical orthogonal function (EOF) methods are used to separate certain environment conditions with the possible effects of aerosol loading. Reanalysis 2, TRMM-3B42 and AERONET data are used from 1999 up to 2012 during September-December. The results show that there are two patterns associated to rainfall-aerosol interaction in La Plata Basin: one in which the dynamic conditions are more important than aerosols to generate rain; and a second one where the aerosol particles have a role in rain formation, acting mainly to suppress rainfall over La Plata Basin.
Wind shear over the Nice Côte d'Azur airport: case studies
Authors: Boilley A. , Mahfouf J.-F.
Published: September 2013

Abstract. The Nice Côte d'Azur international airport is subject to horizontal low-level wind shears. Detecting and predicting these hazards is a major concern for aircraft security. A measurement campaign took place over the Nice airport in 2009 including 4 anemometers, 1 wind lidar and 1 wind profiler. Two wind shear events were observed during this measurement campaign. Numerical simulations were carried out with Meso-NH in a configuration compatible with near-real time applications to determine the ability of the numerical model to predict these events and to study the meteorological situations generating an horizontal wind shear. A comparison between numerical simulation and the observation dataset is conducted in this paper.
Beyond multifractional Brownian motion: new stochastic models for geophysical modelling
Authors: Lévy Véhel J.
Published: September 2013

Abstract. Multifractional Brownian motion (mBm) has proved to be a useful tool in various areas of geophysical modelling. Although a versatile model, mBm is of course not always an adequate one. We present in this work several other stochastic processes which could potentially be useful in geophysics. The first alternative type is that of self-regulating processes: these are models where the local regularity is a function of the amplitude, in contrast to mBm where it is tuned exogenously. We demonstrate the relevance of such models for digital elevation maps and for temperature records. We also briefly describe two other types of alternative processes, which are the counterparts of mBm and of self-regulating processes when the intensity of local jumps is considered in lieu of local regularity: multistable processes allow one to prescribe the local intensity of jumps in space/time, while this intensity is governed by the amplitude for self-stabilizing processes.
Epistemic Cross Talk:
Authors: Hays Priya Venkatesan
Published: September 2013

This article considers the roles of interdisciplinarity as both scholarly activity and social process and their implications for both academia and society. In addressing the interdisciplinarity between the sciences and humanities, rather than emphasizing antagonism, the article asserts that as science grows and expands, so will the humanities, because they both ask and answer separate sets of questions that have distinct intellectual significance and fulfill distinct social needs, which are not necessarily transposed onto neat hierarchical categories, disciplinary or otherwise. These distinctions between the sciences and the humanities are maintained through disciplinary programs emphasizing the epistemic foundations of science and the rhetorical basis of the humanities. In other words, it comes down to episteme. The article also considers the disciplinary confines of science studies and the interdisciplinary program of bioethics and suggests similar epistemic cross talk between the two. It concludes by stating that pursuing interdisciplinarity meets both scholarly and social needs more than would be achieved through solely disciplinary specialization.
International Creation:
Authors: Krug Matthias
Published: September 2013

For Whom the Bell Tolls by Ernest Hemingway is analyzed in this article from a cognitive literary perspective, keeping in mind recent advances in the field of creative cognition.1 Employing the “wave method of cognitive literature analysis” (a “wave theory” was previously employed in linguistic contexts by Bailey), a procedural methodology developed by the writer of this article, it attempts to display the importance of cross-cultural influences in transforming fiction from the first cognitive impulses of the writer to the final linguistic end product.2 In calling for a cognitive incorporation of the reader into the analytical process—what is referred to here as the “writer-reader dynamic”—various linguistic aspects with a solid foundation in linguistic paradigms such as blending theory are examined for their impact on the “creative spaces” of the prototype reader.3 In doing so, this analysis finds Hemingway's creativity deeply entrenched in cross-cultural influences, specifically those of the Spanish Civil War, during which he was a reporter, as well as pointing to the artistic influences of the French painter Paul Cezanne as being of crucial importance in shaping linguistic choices. Hence, Stockwell's assertion that an interaction takes place between texts and humans in the reading of literature is built upon in this article.4
Lymphoepithelioma-like carcinoma of the renal pelvis: Pathological and therapeutic implications
Authors: Modi Hemel , Beckley Ian , Bhattarai Selina , Spencer John , Cartledge Jon
Published: September 2013

A 75-year-old woman presented with a presumed urothelial carcinoma of the right renal pelvis. A radical nephroureterectomy was carried out and histological analysis of the specimen revealed lymphoepithelioma-like carcinoma. This is the seventh reported case of this normally nasopharyngeal tumour found in the renal pelvis. These tumours have a distinct histological appearance comprising sheets of undifferentiated syncytial cells on a background of lymphoid stroma. We review the pathological features of lymphoepithelioma-like carcinoma and make arguments for managing these tumours in a similar way to urothelial carcinoma.
Spontaneous regression of metastatic pulmonary renal cell carcinoma in the setting of sarcomatoid differentiation of the primary tumour
Authors: Chan Brian PH , Booth Christopher M , Manduch Marosh , Touma Naji J
Published: September 2013

We present a case of spontaneous regression of pulmonary metastases from renal cell carcinoma (RCC) with sarcomatoid differentiation, prior to intervention. The patient presented with conventional type RCC with Furhman Grade 4/4 and sarcomatoid differentiation, complicated by pulmonary metastases. Palliative systemic therapy was planned, but prior to the onset of treatment, serial computed tomography scans demonstrated regression of metastatic disease. Spontaneous regression of metastases is rare, but well-documented in conventional clear cell RCC. To the best of our knowledge, this has not previously been described in the setting of sarcomatoid differentiation of the primary tumour.