bluuebunny/crossref_metadata_2025 huggingface dataset:
Tribological Aspects in Aperture Shaping Process
Authors: Nachimowicz Jerzy , Jabłoński Dariusz
Published: March 2013

The article presents tribological aspects in the process of aperture shaping using trepan drills. These tools, also known as trepan cutters, are used for performing port apertures. Due to their structure, only peripheral part (ring) of the aperture is influenced by the milling process, in contrast to milling the whole volume when using twist drills. Due to such method of performing aperture, the power and processing time are significantly reduced. The results of this process are chips and the core that can be used to produce other element, particularly if the material is expensive or if it can be used to examine properties and quality of the material. Trepan drills contain at least four cutting edges and their number increases with the diameter of the tool. This results in forming many chips that interact with the tool and working material during their movement along the chip grooves. During operation of these tools, the tool makes contact with the core and working material. Above effects cause the increase of milling torque and axial force with increasing penetration of the tool into working material and may affect the quality of the created aperture (roughness, microhardness, chemical composition, shape tolerance). In the extreme cases they may also cause the stoppage of device used to drilling or destruction of the milling tool. The article presents also the structure of research station that was used for examination and obtaining sample results of the milling torque and axial force occurred during drilling using trepan drills. Additionally, the values of milling torque and axial force calculated on the basis of theoretical equations are presented. Physical model of the friction process describes, besides effects that occur in the milling area, also other factors that influence the course of the drilling process. The result of drill penetrating the working material is the increase of milling forces, axial forces and temperature. The cause of this effect is the friction between internal and external tool surfaces and the working material, as well as the friction between formed chips and the tool and working material during their movement along the chip grooves. Physical model was the output element to create mathematical model that includes, besides milling force, also forces occurring as a result of interaction among the tool, working material and chips. Additionally, the model includes forces that occur when pressing guide pin to working material.
Application of Hybrid Vision Method for the Hot Aluminium Surface Inspection
Authors: Giesko Tomasz , Garbacz Piotr
Published: March 2013

The paper presents the possibilities of a hybrid vision method based on simultaneous analysis of infrared and vision images for surface inspection of hot aluminium in a manufacturing process. The system consists of a NIR/SWIR camera and a high resolution visual camera, and a computer based image analysis system. The simultaneous analysis of infrared and vision images will enable surface inspection for detecting defects in temperature range from 200°C to 600°C. Thermal images present temperature distribution on the surface, and contain information about the manufacturing process. The analysis of thermograms enables to find areas of temperature irregularity caused by increased friction loads, as well as areas of inhomogeneous emissivity caused by surface defects. Furthermore, information captured by the vision camera is used to detect surface defects. The software developed enables the overlaying of images. The proposed simultaneous thermovision and vision imaging can be applied in industry for in-line monitoring of aluminium extrusion processes.
Application of the 'Iterative Closest Point' Algorithm for Determination of Rotation Axis of a Turntable
Authors: Wróbel Ireneusz
Published: March 2013

Reverse engineering [ is a field of technology which has been under rapid development for several recent years. Optic scanners are basic devices used as reverse engineering tools. Point cloud describes the shape of a scanned object. Automatic turntable is a device which enables a scanning process from different viewing angles. In the paper, the algorithm is described which has been used for determination of rotation axis of a turntable. The obtained axis constitutes the base for an aggregation of particular point clouds into single resultant common cloud describing the shape of the scanned object. Usability of this algorithm for precise scanning of mechanical parts was validated, precision of shape replication was also evaluated.
Influence of Flexible Body Contact Deformation on the Linear Dimension Measurement Precision
Authors: Avišāne Anita , Rudzitis Janis , Upītis Gunārs , Vilcāns Janis
Published: March 2013

The common measurement error when measuring the component geometrical dimensions using universal contact measurement instruments is caused by different factors, such as error of the measurement instrument, personal reading errors, effect of surface roughness on the measuring line deviation, influence of contact deformation measurement force, and others. The present article examines one of these factors, i.e. contact deformations under the influence of measurement force. To make precise measurements it is essential to find out the effect of roughness of measured components. High roughness creates additional measurement errors. It is particularly important in the measurement of thin components, flexible materials and films, as well as for components with nanocoating. Flexible bodies in the meaning of this article are components of different shape and sizes made of rubber or soft plastic. This article studies principles of error formation based on the deformation of surface roughness and basic material.
Identification of Operational Damages of Air-Turbine Engines Using Visual Diagnostics
Authors: Szczepankowski Andrzej , Szymczak Janusz
Published: March 2013

The paper presents various types of compressor and turbine scoops damages that are being found in the operating process of air turbine engines. When dividing them, having in mind a genesis of their origin, a special attention has been paid to corrosion and high-temperature erosion, often being a reason for destruction of the entire unit.
Influence of Heat Treatment on Stress-Corrosion Resistance of EN AW-AIZn5Mg1,5CuZr Alloy
Authors: Kyzioł Lesław , Czapczyk Kazimierz
Published: March 2013

The aim of this study is to determine mechanical properties and stress-corrosion resistance of EN AW-AIZn5Mg1,5CuZr alloy from the aspect of microstructure changes depending on the applied heat treatment. Stress corrosion is caused by the effect of corrosion environment parallel to mechanical stress. It occurs when cracks appear in the metal which is exposed to a corrosion environment and static stretching stresses. The effect of the corrosion environment and stresses on the metal surface cause cracks which are placed perpendicularly to the direction of stretching stresses and may be intercrystalline, intracrystalline or mixed. Stress cracking observations show that distinct cracks are often preceded by the incubation phase. The intensity of microcracks in this phase can be determined by examining changes in mechanical properties caused by changes in alloy structures after various time intervals of the stress-corrosion experiment. This study outlines changes in mechanical properties and resistance of the aluminium alloy in question depending on the heat treatment parameters. Changes in mechanical and corrosion properties are reflected in the structural changes of EN AW-AIZn5Mg1,5CuZr alloy. In order to enhance stress-corrosion resistance and obtain good mechanical properties in Al-Zn-Mg alloys (Zn+Mg>5%), a special heat treatment with cooling with a stop is used. This publication shows suitable heat treatment parameters which guarantee good mechanical properties and high stress-corrosion resistance.
Physical Simulations of the Controlled Rolling Process of Plate X100 with Accelerated Cooling
Authors: Knapiński Marcin , Dyja Henryk , Kawałek Anna , Kwapisz Marcin , Koczurkiewicz Bartosz
Published: March 2013

The research presented in the current paper was carried out for the experimental steel designed for plate which meets the requirements for grade X100 according to API5L. Physical modeling of the rolling process was carried out using the GLEEBLE 3800 simulator. The tested steel is fine-grained constructional steel for making tubes for gas pipelines with the working pressure higher than 15 MPa. The fine-grained structure guarantees excellent plastic properties as well as high impact toughness. After rolling the steel should obtain the minimal yield point of 690 MPa and tensile strength over 760 MPa.
Mining for Knowledge to Build Decision Support System for Treatment of Plano-Valgus
Authors: Dardzińska-Głębocka Agnieszka , Pauk Jolanta
Published: March 2013

Most children with plano-valgus have flexible arches. There is a lot of controversy regarding the results of treatment with foot orthosis, corrective exercises, etc. We hypothesized that data mining and action rule discovery help to understand the relationships among the treatment factors and measurements in order to better understand plano-valgus treatment and gain new knowledge for predicting treatment success. Sixty eligible plano-valgus children and 50 age-matched control children were recruited for this study. The authors developed a flexible temporal feature retrieval system based on grouping the patients of similar visiting frequencies with connection to an action-rules engine, which consists of four modules: a data grouping device, a temporal feature extraction engine, a decision tree classification device, and an action rules generation device.
The Active Thermography Method as Used to Assess the Bearing of Temperature on Thermophysical Properties of Superalloy of a Gas-Turbine Blade
Authors: Błachnio Józef , Kułaszka Artur
Published: March 2013

The method of active thermography is an innovative NDT technology that was developed over the recent years to investigate microstructure condition of machinery components, including components of gas turbines. The essence of the method consists is examination of the thermal response of a material as a function of time to simulation by means of an external heat pulse. When the microstructure contains areas that differ in thermophysical properties, such differences entail alteration of the diffusion velocity. Therefore monitoring of the temperature field that spreads on the surface area of a workpiece that is being cooled down makes it possible to find locations of such different areas. The paper outlines initial results of investigations, carried out with use of the active thermography, how the temperature affects onto thermophysical properties demonstrated by superalloys used for construction of gas turbines. These investigations enabled to find out variations of thermophysical properties of these superalloys as a function of temperature. Eventually they laid down the fundamentals to undertake broader research studies in that domain. The core objective of the studies was to find out the relationships between variations of the thermal impact and corresponding amendments in the response signal received from the investigated material and to detect the correlations that have not yet been defined with sufficient accuracy. The described relationships and liaisons may contribute to development of fundamentals for the new NDT thermographic method suitable to evaluate the overheating status of gas turbine blades.
The Basic Research of Experimental Steels for Pipelines
Authors: Knapiński Marcin , Koczurkiewicz Bartosz , Dyja Henryk , Kawałek Anna , Kwapisz Marcin
Published: March 2013

The requirement for curde oil and natural gas is still increasing. It was observed a growing of interested in the exploration and exploatation of unconventional fuels, including shate gas. There is about 3 to 5 trilion cubic meters resources of that type of gas in Poland. The latest data predicts that in addition to gas in the shale is also petroleum. The development of this branch of mining in our country can cause a significant increase in demand for pipes. The results of basic research of experimental steels for pipe line are presented in this article. Analyse of published materials about steels for pipe line was done. The chemical composition of two types of new steels meeting the requirements for X80 and X100 grade plates according API 5L norm were developed. The heat tratment using dilatometer DIL 805A/D were carried out. The influnce of heat temperature before rolling proces on structure of austenite was defined. The heating schemes were proposed for obtaining a high yield, while not allowing the dissolution of the alloying elements inhibit austenite grain overdevelopment. For samples after tests the structure of primary austenite and the size of former austenite grains were determined. The influence of deformation cinditions on structure were determinated, too. The results obtained from the examinations will be used to develop a technology for rolling sheets of pipelines in the category of X80 and X100 according to the API.
Changes of Free Radical Content in Exposed to Electrons GUR1020 and GUR1050 Polyethylene Types Intended for Endoprosthesis Acetabular Cups
Authors: Czaja Piotr , Maszybrocka Joanna , Michniowski Jacek , Cybo Jerzy , Barylski Adrian
Published: March 2013

The paper presents the results of the EPR examination of free radical content in GUR1020 and GUR1050 polyethylenes which were irradiated with an electron beam. Changes in the amount of radicals in the period of 12 months in the UHMWPE cross-linked with a dose of 26-156 kGy were analysed. Spectra registered 90 days after irradiation show a hyperfine structure. An image consisting of 7 characteristic lines is the most similar pattern that can be used to analyse this spectrum. Subsequent measurements (255 and 372 days after irradiation) produce images consisting of one resonance line. Alkyl and allyl radicals generated during the irradiation are the source of the EPR signal. The influence of atmospheric oxygen causes further changes of the radicals mentioned above, which leads to the formation of peroxyl radicals. The content of radicals in the polymer and its changes over time were calculated. The amount of radicals increases as the absorbed dose grows, but decreases over time. Comparative measurements of the material subjected to thermal processing at the temperature of 423 K have shown that in this case, no resonance lines are present, which testifies to the effective elimination of free radicals by means of UHMWPE recrystallisation.
Evaluation of the Possibility of Mucin Adsorption onto Implantation Materials
Authors: Mystkowska Joanna , Suder Piotr , Drabik Anna , Bodzoń-Kułakowska Anna , Silberring Jerzy , Dąbrowski Jan Ryszard
Published: March 2013

The aim of the work was the assessment of adsorption capabilities of selected animal mucins. In this work two animal mucins (mucin porcine stomach, type II and III), which were dissolved in phosphate buffered saline were evaluated. The tested materials, where the adsorption of glycoproteins takes place, were surfaces of two implantation materials: titanium alloy (Ti-6Al-4V) and 316L steel. The standardized samples of materials were immersed in solution of mucin II and solution of mucin III aseptically prepared) for: 10 minutes, 120 minutes, 1 day and 5 days. The UV spectrophotometry method was used for analysis of the mucin concentrations as a simple and effective technique. The obtained results clearly indicate that the tested surfaces are covered by the mucins used for experiments. However, quantitative analyses of adsorbed mucins did not show significant differences, both between tested materials, and mucins.
Tribological Properties of Selected Self-Made Solutions of Synthetic Saliva
Authors: Mystkowska Joanna , Jałbrzykowski Marek , Dąbrowski Jan Ryszard
Published: March 2013

The present paper describes the results of tests on the influence of selected self-made solutions of synthetic saliva on tribological characteristics of implant materials on the example of the Co-Cr-Mo alloy. The used saliva substitutes were prepared on the basis of gums (xanthan, guar, arabic and carob bean) dissolved in saline buffer. Analysis of the values of the coefficient of friction and the wear of the tested dental alloy in tested solutions was performed. Different values of the coefficient of friction were observed for friction pairs tested in individual solutions. Its lowest values were achieved during tests using xanthan gum with SDS (sodium dodecyl sulfate) addition, and the highest values were achieved for xanthan gum. As regards wear analysis, its lowest value was registered during lubrication with natural saliva. Among saliva substitutes, the lowest value of mass wear of dental alloy was observed in solution of xanthan gum, and the highest value was registered for carob bean gum. After friction tests, elements of the friction pair were subjected to microscope analysis using the Olympus BX61 optical microscope.
Axisymmetric Heat Conduction Problem for a Half-Space Covered with a Laminated Coating of Periodic Structure
Authors: Kołodziejczyk Waldemar , Kulchytsky-Zhyhailo Roman
Published: March 2013

The paper deals with a stationary heat conduction problem for a microperiodic, two-layered coating on a homogeneous half-space. The distribution of temperature and heat fluxes are obtained within the frame of the homogenized model with microlocal parameters [1,2, and within the framework of the classical heat conduction problem for a periodically layered structure. The influence of number of layers in the coating on the heat flux and temperature is analyzed.
High Power Diode Laser Cladding of Wear Resistant Metal Matrix Composite Coatings
Authors: Janicki Damian Michał
Published: March 2013

The paper describes the application of high power direct diode laser (HPDDL), with a rectangular laser beam spot of size 1.8x6.8 mm, for the cladding of Ni-based alloy (NiSiB)+WC composite coatings. The laser cladding process was carried out with a direct injection of cladding powder into the melt pool. The influence of parameters, such as laser power beam (heat input) and WC particles size in the cladding powder on the coatings microstructure and wear properties was investigated. The microstructure and morphology of the coatings were assessed by optical and scanning electron microscopy. Wear properties of the coatings were investigated using abrasive and erosive wear tests. The results showed that a proper selection of laser cladding parameters provides non-porous coatings with excellent metallurgical bonding and a homogeneous distribution of WC particles. The dissolution of WC particles increases with the size of WC particles decreasing in the cladding powder and increasing the laser power level (heat input). The coatings containing WC particles in size range of 100-200 µm provide the highestwear resistance under erosive and abrasiveconditions.
Partition of the Optimality Problems in Mechatronics
Authors: Tarnowski Wojciech
Published: March 2013

In the paper two examples of division of the mathematical model for optimization are presented: a drive composed of an electric motor and mechanical transmissions, and an electromagnetic multi-coil linear drive. The first example shows that each step of the mechanical transmission may be optimized separately, if an overall power efficiency and a mass are taken as the optimality criteria for the whole drive, provided the adequate coordination variables are adopted, and these are ratios of the gears. In the other example it is demonstrated that the whole problem may be divided into three sub-problems, accordingly to the computing environment: ordinary differential equations are applied to model a mechanical part, and partial differential equations are modelling an electromagnetic field and a voltage distribution, with the moving core. The transient position of the core is the coordination variable. Finally, methodological suggestions on the systematic way of decomposing a design problem into sub-problems are proposed.
The Method of Assessment of Suitability of the Bearing System Based on Parameters of Technical and Adjustment State
Authors: Lindstedt Paweł , Sudakowski Tomasz
Published: March 2013

In the operation process, a complex method evaluating technical condition and regulatory status (activities) of the bearing system is used. The method of determination of technical parameters and operating status is known. This is achieved through the interaction of two coupled equations and [2, 3, 7]. It was demonstrated that, on the basis of waveform parameters of technical condition and operating status (respectively), the identification of parametric and momentary damage can be carried out. During the identification process of parametric and momentary damage, it is assumed that damage arises when a parameter threshold value at the time of operation is greater than current permissible value. It is shown how the threshold value of the parameter and its current permissible value, taking into account the number of measurements, are determined.
The Multilevel Prognosis System Based on Matrices and Digraphs Methods
Authors: Hetmańczyk Mariusz Piotr
Published: March 2013

The author of this article considers new approach based on operational reliability models, written in the form of matrices and digraphs methods. At a core of the method the author used the theory of systems and their decomposition consistent with the FMEA methodology [, that allows a simplification of the distribution of elements within the system into smaller parts having a greater susceptibility to the error analysis and forecasting of their states. The method mainly refers to decentralized systems, linked via reciprocal relationships (that can be applied to manufacturing work centres, transport lines, etc.), containing subsystems that use the control, power, noise and mass flows streams. Article includes also main assumptions of described method, realizability studies, application areas and significant restrictions.
The Reliability Model of AC-Asynchronous Drive Based on the Multilevel Prognosis System Supported by Matrices and Digraphs Methods
Authors: Hetmańczyk Mariusz Piotr
Published: March 2013

Author of this article presents an authorship reliability model of a AC-asynchronous drive written in accordance with assumptions of the multilevel prognosis system based on matrices and digraphs methods. Described model take advantage of knowledge gathered from specialists on the basis of their experience. It is worth to stress that parameters of the reliability model of the AC-drive meet the requirements of units utilized in case of distributed drives. Each change of its application range requires a modification of internal parameters, but the functional structure remains without any variations, because presented reliability model has been based on the functional structure. An intention of the author is focused on an elaboration of a collection of reliability models [ of distributed drives components, prepared in accordance with the multilevel system of prognosis based on matrices and digraphs methods. The model has been specified to the level of the independent subsystem. This approach allows the use of this model in the analysis of complex systems, consisting of separated drive subsystems, which meet the requirements of the method. Using multilevel prediction models should be possible in all applications of electric drives, regardless of purpose functions.
Harmonic Balance Analysis for the Rigid Finite Element Model of the Rotating Cracked Shaft
Authors: Kulesza Zbigniew
Published: March 2013

The paper presents a multi-dimensional harmonic balance analysis utilized to study the vibration responses of the cracked rotor subject to gravity, unbalance and an additional lateral harmonic force generated by an active magnetic bearing. The nonlinear terms resulting from the shaft crack are included via an alternating frequency/time domain (AFT) method. The example addressed in this paper is a simple rotor modeled by using the rigid finite element (RFE) approach. Combination frequencies are recognized as evident symptoms of the shaft crack.
Review of Aflibercept for the Treatment of Neovascular Age-Related Macular Degeneration
Authors: Stewart Michael W.
Published: March 2013

The treatment of exudative age-related macular degeneration (AMD) has been completely transformed by the development of drugs that bind vascular endothelial growth factor (VEGF). The antibody-based VEGF inhibitors bevacizumab and ranibizumab usually prevent the enlargement of choroidal neovascular membranes, reduce vascular permeability, and improve visual acuity. The newest VEGF inhibitor, aflibercept, is a soluble fusion protein that binds all isoforms of VEGF-A, VEGF-B, and placental growth factor with high affinity. Preclinical studies demonstrated aflibercept's ability to prevent experimental neovascularization and tumor growth in animal models. In phase 3 trials for exudative AMD, patients who received aflibercept avoided moderate vision loss and experienced improved visual acuity comparable to those who received ranibizumab. Additionally, patients who were treated with aflibercept 2 mg every 8 weeks (after 3 monthly loading doses) had similar visual results to those treated every 4 weeks. When treated as needed during the second year of the trials, patients were able to last an average of 3 months between aflibercept injections. Since its regulatory approval, aflibercept has also been found to perform well as a salvage therapy for eyes that respond incompletely to ranibizumab and bevacizumab. Because aflibercept can be administered less frequently than ranibizumab, it promises to decrease the frequency of patients’ visits to physicians’ offices in addition to the overall cost of AMD therapy.
A mathematically assisted reconstruction of the initial focus of the yellow fever outbreak in Buenos Aires (1871)
Authors: Fernández M. L. , Otero M. , Schweigmann N. , Solari H. G.
Published: March 2013

We discuss the historic mortality record corresponding to the initial focus of the yellow fever epidemic outbreak registered in Buenos Aires during the year 1871 as compared to simulations of a stochastic population dynamics model. This model incorporates the biology of the urban vector of yellow fever, the mosquito Aedes aegypti, the stages of the disease in the human being as well as the spatial extension of the epidemic outbreak. After introducing the historical context and the restrictions it puts on initial conditions and ecological parameters, we discuss the general features of the simulation and the dependence on initial conditions and available sites for breeding the vector. We discuss the sensitivity, to the free parameters, of statistical estimators such as: final death toll, day of the year when the outbreak reached half the total mortality and the normalized daily mortality, showing some striking regularities. The model is precise and accurate enough to discuss the truthfulness of the presently accepted historic discussions of the epidemic causes, showing that there are more likely scenarios for the historic facts. Received: 9 October 2012,  Accepted: 1 March 2013; Edited by: G. Mindlin; DOI: http://dx.doi.org/10.4279/PIP.050002Cite as: M L Fernández, M Otero, N Schweigmann, H G Solari, Papers in Physics 5, 050002 (2013)
Prevalence of Head and Neck Cancer in the State of Meghalaya: Hospital-based Study
Authors: Shunyu Neizekhotuo Brian , Syiemlieh Judita
Published: March 2013

In India, 20 to 40% of all cancer arises in the head and neck region. The highest rate is seen in the eastern and southern regions of our country. The alarming high prevalence of head and neck cancer (HNC) in this region has prompted us to undertake this retrospective study. This study is to give the picture on the prevalence of HNC in the region, as such studies are lacking, till date. This is a 5 years retrospective study of cancer patients from 2007 to 2011 who have been registered in Civil Hospital, Shillong. The period of study is short as registry before 2007 was not properly recorded, but the high prevalence of cancer especially HNC warranted the need to undertake this retrospective study. During the 5-year period, there were a total of 3,123 cancer patients, registered in Civil Hospital, Shillong. In this study, HNC and esophageal cancer constitute 2,207 (70.67%) cases of the total body malignancy (TBM) which is much higher than other studies done in other parts of the country. Fourth decade is the most common age group comprising of 471 cases which accounts for 32.72% of all HNC. This high prevalence of HNC in the young population of the region is alarming and hence needs a comprehensive afford to meet this challenge.

This paper, therefore, is an attempt to quantify the spectrum of HNC in the region hoping that this paper will help the health professionals to understand the burden of HNC in the region, so as to generate strategies for future planning.

How to cite this article

Shunyu NB, Syiemlieh J. Prevalence of Head and Neck Cancer in the State of Meghalaya: Hospital-based Study. Int J Head and Neck Surg 2013;4(1):1-5.
Electromyographic Assessment of Accessory Nerve Function Following Nerve Sparing Neck Dissection
Authors: Raj Sagaya , Merchant Shuaib , Mohiyuddin Azeem , LNU Oomen , Kottaram Philip John
Published: March 2013

Aims

To assess preoperative and postoperative shoulder function by electromyography (EMG) in spinal accessory nerve (SAN) sparing neck dissections in head and neck cancers.

Materials and methods

A prospective study was done on 50 patients (51 shoulders) with histopathologically proven head and neck cancers with N0 or N1 neck who underwent nerve sparing neck dissections. Patients were assessed preoperatively and postoperatively at 3 weeks and 3 months by needle EMG and muscle strength tests of upper trapezius.

Results

and interpretation: At 3 weeks postoperatively, 11 shoulders (39.3%) in FND group and four shoulders (33.3%) in modified radical neck dissection (MRND) group showed severely abnormal EMG, while in supraomohyoid neck dissection (SOHND) group only two (18.2%) shoulders showed severely abnormal EMG. All patients who underwent nerve sparing neck dissections showed improvement in at least one category on the second electromyogram at 3 months. This could be attributed to neuropraxia or transient devascularization of the accessory nerve. In our study, 11 patients in FND group showed severely abnormal EMG finding, but they did not have as great a degree of shoulder dysfunction as would be expected. This could be due to factors like preoperative condition of other synergistic shoulder girdle muscles, postoperative exercises, etc.

Conclusion

SAN injuries are common in all types of nerve sparing neck dissections requiring aggressive physiotherapy for an improved shoulder function. To conclude, in patients in whom it is oncologically sound, nerve sparing neck dissections offers significant benefit in terms of shoulder function.

How to cite this article

Mohiyuddin A, Raj S, Merchant S, Oomen, Kottaram PJ. Electromyographic Assessment of Accessory Nerve Function Following Nerve Sparing Neck Dissection. Int J Head and Neck Surg 2013;4(1):19-23.
Interesting Clinical Presentation of Myxoid Liposarcoma of Oropharynx
Authors: Raj Sagaya , Merchant Shuaib , Mohiyuddin Azeem , Arun P
Published: March 2013

Aims

To describe an unusual presentation of myxoid liposarcoma of oropharynx and a brief review of literature.

Introduction

Liposarcomas of head and neck are very rare. Its treatment and prognosis mainly depends on the site and the histologic pattern of the tumor.

Case presentation

The present case report describes a 65-year-old male with complaints of dysphagia, dyspnea, and a peculiar complaint of mass in the throat which turned out to be a low-grade myxoid liposarcoma arising from right lateral wall of oropharynx extending intraluminal in the esophagus, compressing posterior wall of trachea. The mass was successfully excised surgically and postoperative period was uneventful and patient was asymptomatic 4 months after surgery.

Conclusion

Myxoid liposarcoma is a rare tumor in head and neck and surgical excision with adequate margin is the treatment of choice.

How to cite this article

Mohiyuddin A, Raj S, Merchant S, Arun P. Interesting Clinical Presentation of Myxoid Liposarcoma of Oropharynx. Int J Head and Neck Surg 2013;4(1):57-58.
Molecular Characterization of Some Genetic Factors Controlling Spermatogenesis in Egyptian Patients with Male Infertility
Authors: Fayez Alaaeldin Gamal , El-Sayed Amr Saad , El-Desouky Mohamed Ali , Zarouk Waheba Ahmed , Kamel Alaa Khalil , Fahmi Ibrahim Mohamed , El-Ruby Mona Omar
Published: March 2013

Men with severe infertility suffer a high risk of Y chromosome deletion, hence screening for these cases is recommended prior to treatment with assisted reproduction. Our study aimed to investigate and detect the azoospermia factor (AZF) region deletion, rearrangement and deleted azoospermia (DAZ) gene copy number variations in Egyptian azoospermic infertile men. This was tested on 54 Egyptian nonobstructive azoospermic (NOA) infertile men, with age ranged from 21 to 45 years (mean: 31.4 ± 6.1 years), by STS ± multiplex PCR using a set of 14 sequence tagged sites (STSs) from three different regions of the Y chromosome: AZFa, AZFb, AZFc and sY587/DraI PCRRFLP assay to determine DAZ copy number variations. The results revealed a significant prevalence of AZFc subtypes deletion and reduced DAZ gene dosage in Egyptian azoospermic cases affecting Y chromosome deletions. To our knowledge, this study is the first one to investigate AZFc subtypes deletion and DAZ gene dosage in Egyptian infertile men. We concluded that DAZ genes deletion is a risk factor for spermatogenic damage.

How to cite this article

Fayez AG, El-Sayed AS, El-Desouky MA, Zarouk WA, Kamel AK, Fahmi IM, El-Ruby MO. Molecular Characterization of Some Genetic Factors Controlling Spermatogenesis in Egyptian Patients with Male Infertility. Int J Infertility Fetal Med 2012;3(3):69-77.
A Rare Case of Vaginal Dermoid Cyst: A Case Report and Review of Literature
Authors: Sharma Richa , Nagraj Shashikala
Published: March 2013

Vaginal dermoid cyst is a rare condition. Ultrasound is the investigative tool and treatment is surgical through a transvaginal approach.

How to cite this article

Sharma R, Rao KA, Nagraj S. A Rare Case of Vaginal Dermoid Cyst: A Case Report and Review of Literature. Int J Infertility Fetal Med 2012;3(3):102-104.
Iodine monoxide in the Western Pacific marine boundary layer
Authors: Großmann K. , Frieß U. , Peters E. , Wittrock F. , Lampel J. , Yilmaz S. , Tschritter J. , Sommariva R. , von Glasow R. , Quack B. , Krüger K. , Pfeilsticker K. , Platt U.
Published: March 2013

Abstract. A latitudinal cross-section and vertical profiles of iodine monoxide (IO) are reported from the marine boundary layer of the Western Pacific. The measurements were taken using Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) during the TransBrom cruise of the German research vessel Sonne, which led from Tomakomai, Japan (42° N, 141° E) through the Western Pacific to Townsville, Australia (19° S, 146° E) in October 2009. In the marine boundary layer within the tropics (between 20° N and 5° S), IO mixing ratios ranged between 1 and 2.2 ppt, whereas in the subtropics and at mid-latitudes typical IO mixing ratios were around 1 ppt in the daytime. The profile retrieval reveals that the bulk of the IO was located in the lower part of the marine boundary layer. Photochemical simulations indicate that the organic iodine precursors observed during the cruise (CH3I, CH2I2, CH2ClI, CH2BrI) are not sufficient to explain the measured IO mixing ratios. Reasonable agreement between measured and modelled IO can only be achieved if an additional sea-air flux of inorganic iodine (e.g., I2) is assumed in the model. Our observations add further evidence to previous studies that reactive iodine is an important oxidant in the marine boundary layer.
Temperature-dependent accumulation mode particle and cloud nuclei concentrations from biogenic sources during WACS 2010
Authors: Ahlm L. , Shakya K. M. , Russell L. M. , Schroder J. C. , Wong J. P. S. , Sjostedt S. J. , Hayden K. L. , Liggio J. , Wentzell J. J. B. , Wiebe H. A. , Mihele C. , Leaitch W. R. , Macdonald A. M.
Published: March 2013

Abstract. Submicron aerosol particles collected simultaneously at the mountain peak (2182 m a.s.l.) and at a forested mid-mountain site (1300 m a.s.l.) on Whistler Mountain, British Columbia, Canada, during June and July 2010 were analyzed by Fourier transform infrared (FTIR) spectroscopy for quantification of organic functional groups. Positive matrix factorization (PMF) was applied to the FTIR spectra. Three PMF factors associated with (1) combustion, (2) biogenics, and (3) vegetative detritus were identified at both sites. The biogenic factor was correlated with both temperature and several volatile organic compounds (VOCs). The combustion factor dominated the submicron particle mass during the beginning of the campaign, when the temperature was lower and advection was from the Vancouver area, but as the temperature started to rise in early July, the biogenic factor came to dominate as a result of increased emissions of biogenic VOCs, and thereby increased formation of secondary organic aerosol (SOA). On average, the biogenic factor represented 69% and 49% of the submicron organic particle mass at Whistler Peak and at the mid-mountain site, respectively. The lower fraction at the mid-mountain site was a result of more vegetative detritus there, and also higher influence from local combustion sources. The biogenic factor was strongly correlated (r~0.9) to number concentration of particles with diameter (Dp)> 100 nm, whereas the combustion factor was better correlated to number concentration of particles with Dp<100 nm (r~0.4). The number concentration of cloud condensation nuclei (CCN) was correlated (r~0.7) to the biogenic factor for supersaturations (S) of 0.2% or higher, which indicates that particle condensational growth from biogenic vapors was an important factor in controlling the CCN concentration for clouds where S≥0.2%. Both the number concentration of particles with Dp>100 nm and numbers of CCN for S≥0.2% were correlated to temperature. Considering the biogenic influence, these results indicate that temperature was a primary factor controlling these CCN concentrations at 0.2% supersaturation.
Ground-based stratospheric O3 and HNO3 measurements at Thule, Greenland: an intercomparison with Aura MLS observations
Authors: Fiorucci I. , Muscari G. , Froidevaux L. , Santee M. L.
Published: March 2013

Abstract. In response to the need for improving our understanding of the evolution and the interannual variability of the winter Arctic stratosphere, in January 2009 a ground-based millimeter-wave spectrometer (GBMS) was installed at the Network for the Detection of Atmospheric Composition Change (NDACC) site in Thule (76.5° N, 68.8° W), Greenland. In this work, stratospheric GBMS O3 and HNO3 vertical profiles obtained from Thule during winters 2010 (HNO3 only), 2011 and 2012 are characterized and intercompared with co-located Aura MLS measurements. Using a recently developed algorithm based on Optimal Estimation, we find that the GBMS O3 retrievals show good sensitivity (> 80%) to atmospheric variations between ~ 17 and ~ 50 km, where their 1σ uncertainty is estimated to be the larger of ~ 11% or 0.2 ppmv. Similarly, HNO3 profiles can be considered for scientific use between ~ 17 and ~ 45 km altitude, with a 1σ uncertainty that amounts to the larger of 15% or 0.2 ppbv. Comparisons with Aura MLS version 3.3 observations show that, on average, GBMS O3 mixing ratios are biased low with respect to MLS throughout the stratosphere, with differences ranging between ~ 0.3 ppmv (8%) and 0.9 ppmv (18%) in the 17–50 km vertical range. GBMS HNO3 values display instead a high bias with respect to MLS up to 26 km, reaching a maximum of ~ 1 ppbv (10%) near the mixing ratio profile peak. O3 and HNO3 values from the two data sets prove to be well correlated at all altitudes, although their correlations worsen at the lower end of the altitude ranges considered. Column contents of GBMS and MLS O3 (from 20 km upwards) and HNO3 (from 17 km upwards) correlate very well and indicate that GBMS measurements can provide valuable estimates of column interannual and seasonal variations for these compounds.
Distribution of ultraphytoplankton in the western part of the North Pacific subtropical gyre during a strong La Niña condition: relations with the hydrological conditions
Authors: Girault M. , Arakawa H. , Barani A. , Ceccaldi H. J. , Hashihama F. , Kinouchi S. , Gregori G.
Published: March 2013

Abstract. The distribution of ultraphytoplankton was investigated in the western North Pacific Subtropical Gyre (NPSG) during La Niña, a cold phase of El Niño Southern Oscillation (ENSO). Observations were conducted along a 141.5° E transect (33.6° N–13.25° N) in order to study the ultraplankton assemblages in various oligotrophic conditions. Analyses were performed at the single cell level by analytical flow cytometry. Five ultraphytoplankton groups (Prochlorococcus, Synechococcus, picoeukaryotes, nanoeukaryotes and nanocyanobacteria) defined by their optical properties were enumerated in three different areas visited during the cruise: the Kuroshio region, the subtropical Pacific gyre and a transition zone between the subtropical Pacific gyre and the Warm pool. Prochlorococcus outnumbered the other photoautotrophs in all the investigated areas. However in terms of carbon biomass, an increase in the relative contribution of Synechococcus, picoeukaryotes and nanoeukaryotes was observed from the centre of the subtropical gyre to the Kuroshio area. In the Kuroshio region, a peak of abundance of nanoeukaryotes observed at the surface suggested an increase in nutrients likely due to the vicinity of a cold cyclonic eddy. In contrast, in the salinity front (35) and anticyclonic eddy located around 22.83° N, the mainly constant distribution of Prochlorococcus from the surface down to 150 m characterized the dominance by these microorganisms in high salinity and temperature zone. Results suggested that distribution of nanocyanobacteria is also closely linked to the salinity front rather than low phosphate concentration. The maximum abundance of ultraphytoplankton was located above (> 100 m) the SubTropical Counter Current (STCC) where higher nutrient concentrations were measured. Finally, comparison of the ultraphytoplankton concentrations during El Niño (from the literature) and La Niña (this study) conditions seems to demonstrate that La Niña conditions lead to higher concentrations of Synechococcus in the Subtropical gyre and a lower abundance of Synechococcus in the Kuroshio region. Our results suggest that the west part of NPSG is a complex area, where different water masses, salinity fronts and eddies lead to an heterogeneous distribution of ultraphytoplankton assemblages in the upper layer of the water column.
The influence of food supply on the response of Olympia oyster larvae to ocean acidification
Authors: Hettinger A. , Sanford E. , Hill T. M. , Hosfelt J. D. , Russell A. D. , Gaylord B.
Published: March 2013

Abstract. Increases in atmospheric carbon dioxide drive accompanying changes in the marine carbonate system as carbon dioxide (CO2) enters seawater and alters its pH (termed "ocean acidification"). However, such changes do not occur in isolation, and other environmental factors have the potential to modulate the consequences of altered ocean chemistry. Given that physiological mechanisms used by organisms to confront acidification can be energetically costly, we explored the potential for food supply to influence the response of Olympia oyster (Ostrea lurida) larvae to ocean acidification. In laboratory experiments, we reared oyster larvae under a factorial combination of pCO2 and food level. High food availability offset the negative consequences of elevated pCO2 on larval shell growth and total dry weight. Low food availability, in contrast, exacerbated these impacts. In both cases, effects of food and pCO2 interacted additively rather than synergistically, indicating that they operated independently. Despite the potential for abundant resources to counteract the consequences of ocean acidification, impacts were never completely negated, suggesting that even under conditions of enhanced primary production and elevated food availability, impacts of ocean acidification may still accrue in some consumers.
Snow on the Ross Ice Shelf: comparison of reanalyses and observations from automatic weather stations
Authors: Cohen L. , Dean S.
Published: March 2013

Abstract. An analysis of precipitation from the ECMWF ERA-Interim and NCEP/NCAR Reanalysis-2 datasets is developed using snow accumulation measurements from Automatic Weather Stations (AWS) around the Ross Ice Shelf (RIS), Antarctica. The high temporal resolution of the AWS snow accumulation measurements allow for a new, event-based comparison of reanalyses precipitation to in-situ observations. Snow accumulation records from nine AWS provide multiple years of accumulation data between 2008–2012 over a relatively large, homogeneous region of Antarctica and provide the basis for a statistical evaluation of accumulation events. The analysis shows that ERA-Interim reproduces significantly more precipitation events than NCEP-2 and these events correspond to an average 8.2% more precipitation. Correlations between reanalyses and AWS event sizes are seen at several stations (at > 90% significance levels) and show that ERA-Interim consistently produces larger precipitation events than NCEP-2. The significant and complex effects of wind on snow accumulation (which can both limit and enhance accumulation) make determining biases in the reanalyses data not possible with the AWS data, however the analysis does illustrate significant and important differences between ERA-Interim and NCEP-2 precipitation.
The Basis CL Cemented Femoral Stem: Results after 8.9 Years Follow-up
Authors: Mai Sabine , Golla Matthias , Siebert Werner E.
Published: March 2013

This prospective study was conducted to demonstrate that the matte-finish Basis CL cemented endoprosthetic stem delivers good qualitative results after 10 years. Between January and December 1999, 205 consecutive hips (201 patients; 74.5 ± 6.8 years at surgery) underwent primary total hip arthroplasty with the Basis CL and the same acetabular cup (RM Classic cup) at a single institution. Follow-up data at 10 years was available for 120 hips (average follow-up of 8.9 years, ±2.9). Mean Harris Hip Score improved from 39.5 ± 16.8 at baseline to 75.9 ± 16.7 at 10-year follow-up (p<0.001). Four hips required revision during the study: three for infection and one for pain. There were no cases of aseptic loosening, implant migration, or stem fracture. Cumulative survival at 10 years was 97.4% with the endpoint of revision for any reason. In conclusion, results with the matte-finish cemented Basis CL indicated that it was safe and effective after medium-term follow-up.