bluuebunny/crossref_metadata_2025 huggingface dataset:
Tolerance Design for Optimal Dimensional Quality of Machine Parts
Authors: Frumuşanu Gabriel , Epureanu Alexandru
Published: June 2016

The mechanical systems consist of assembled parts, between which diverse interactions take place. Tolerance analysis purpose is to study the effects of part geometric deviations on assembly functional requirements. In the current approaches from this field, the part geometrical deviations are toleranced without considering the evolution of the geometrical deviations during product exploitation. As consequence, between two parts identical as type but with different values of their geometrical features, inside the designed tolerance zones, any difference is made despite they might have significantly different life cycles or manufacturing costs. This paper presents a new conceptual approach concerning parts tolerance design, based on a new criterion, namely the dimensional quality, defined by two important features: life cycle and manufacturing cost. The main issue of this approach is the optimal relation between the manufacturing tolerance zones and the acceptable functional deviation domain. The new concept implementation is sampled in the case of an articulated arm.
Six Links Passive Modular Group Applied to the Inverse Structural Model of the Bi-Mobile Leg Mechanisms
Authors: Comanescu Adriana , Zaleschi Claudiu , Ungureanu Liviu , Dugaesescu Ileana , Alionte Cristian
Published: June 2016

The structural synthesis of bi-mobile mechanisms has some particularities. The effector of such systems must have the motion dependent on two independent parameters, the selection of the basis and the effector in the linkage being made through the inverse structural model. The active pair placement in the linkage is imposed by the conditions settled to the system by its direct structural model. Due to the theoretical difficulties of mathematical models the passive complex modules with six links are rarely met in construction and design of mechanisms. The relevance of the paper is given by the possibility to create new original structures applying six links passive modular groups.
Design and Analysis of Multi-Point System for Forming Three Dimensional Free-Form Surfaces
Authors: Kadhim Abdul Kareem Jalil , Neama Ragad Aziz
Published: June 2016

Multi-point Sheet metal forming is a flexible technique in which a discrete punches are used to generate the continuous 3-D surface . The proposed die comprises a set of matrices of a closely stacked discrete punches arranged to form a cavity in which a free form surface can be formed .The working surface of the multi-point die are modeled by a uniform B-spline and constructed by adjusting the height of each punch manually. Finite element simulation for the process was performed to study the effect of punch number on the shape error and thickness variation. Experimental work include the building of multi-point die to form the aluminum sheets. The effect using rubber interpolators on dimpling defect were also studied . The results revealed that thickness variation error between the numerical and experimental results is equal to 5% .
The Potential of Renewable Energy in the Republic of Moldova: A Case Study
Authors: Lakatos Elena Simina , Greenley Matthew , Bacali Laura , Boscoianu Mircea , Vaida Razvan
Published: June 2016

This article presents evidence to support the Republic of Moldova’s foreign energy dependence by providing information related to their current energy situation, energy imports and associated costs.The article places a specific emphasis on locating the primary origins and effects of Moldova’s energy dependency and examines the potential of renewable energy sources to diminish this energy dependency. In order to conduct the research for this article, data was collected through semi-structured interviews that were carried out in Moldova. Various energy experts and other officials and practitioners were interviewed. Information was also retrieved from a variety of sources that included the Moldova Country Report on Moldova’s Energy Sector and from the United Nations Development Program’s Moldova Energy and Biomass Project. The article shows that Moldova is in a position of energy dependence but there is potential from renewable energy sources to decrease this dependency.
Study the Strength of Material and Composite Structures of Belly-Landing Mini UAV
Authors: Soetanto Maria Fransisca , Tritjahjono Rachmad Imbang
Published: June 2016

This paper consists of the design and analysis of the strength of material composite of the fuselage of a Belly-Landing Mini Unmanned Aerial Vehicle (UAV). A belly landing UAV occurs when an UAV lands without its landing gear and uses its underside, or belly, as its primary landing device. Belly landings carry the risk that the UAV may flip over, disintegrate, or catch fire if it lands too fast or too hard [1], so the more important designs parameters for materials used are the specific strength and specific stiffness. Specific strength is defined as the ultimate tensile strength divided by material density, and specific stiffness is defined as Young’s modulus of the material divided by density [Franklin, 2010]. The aim of this Belly Landing Mini UAV is for used in situations where manned flight is considered too risky or difficult and no runway for take-off or landing, such as fire fighting surveillance, while the term 'mini’ means the design of this UAV has a launch mass greater than 100 grams but less than 100 kilograms [2], the objective of this project is the development and design of materials fuselage of a mini UAV with two layer sandwich structures made from composite materials and epoxy resin. For that purposes, 3 variations of the composite materials tensile test specimens have been manufactured in accordance with ASTM D3039 standard and tested its strength. The results showed that the fibre glass and fibre carbon composite with resin epoxy has the maximum tensile strength and Young’s modulus, so that the fabrication and manufacturing of the fuselage component is made by using that material composite. The Von Mises stress is used to predict yielding of materials under any loading condition from results of simple uniaxial tensile tests by using software Autodesk Inventor 2012. The results show that the design is safe caused the strength of material is greater than the maximum value of Von Mises stress induced in the material. The results of flight tests show that this small UAV has successfully manoeuvred to fly, such as take off, some acrobatics when cruising and landing smoothly, which means that the calculation and analysis of structure and material used on the fuselage of the Mini UAV was able to be validated.
A Study on Hovercraft Resistance Using Numerical Modeling
Authors: Phan Anh Tuan
Published: June 2016

Hovercraft operates on multi-terrains such as on water surface, on roads, on mud, on non-flat surfaces... it is used popular on the world. With the ability of operating on multi-terrains at high speed, hovercraft is used for many purposes, such as on surveying and rescues missions on areas that are not reachable by normal vehicles, on military missions and traveling... Currently, methods for estimating hovercraft resistance are not accurate enough due to many experiential formulae and coefficients involved during calculating process. This paper presents a method for calculating hovercraft resistance using computational fluid dynamics (CFD) tools. This research method is used popular and modern research method on the world. The method was applied for calculating resistance of a 7 meters length hovercraft model. The modelling results give us suggestions in selecting engine power and operating speeds for minimizing fuel consumption.
Design Optimization of Rotor Lock Disc for Horizontal Axis Wind Turbine Generator
Authors: Augusto Gerardo Lumagbas , Culaba Alvin B. , Gan Lim Laurence A. , Maglaya Archie B.
Published: June 2016

This study presents design optimization of rotor lock disc in the generator rotor which was analyzed by applying the respective lateral force taken from machine load calculation for a 2.5 MW permanent magnet direct-drive wind turbine generator. The machine load calculation result was derived from GH Bladed software output. The maximum tensile stress, internal stresses such as von Misses, maximum displacement and corresponding safety factor were calculated in terms of theoretical stress concentration factor due to discontinuity or change in cross-section in the region where the rotor lock is present. The rotor lock disc configuration was optimized to satisfy a safety factor of unity using exhaustive search method and Cosmos works software. Calculation results indicated that the safety factor of rotor lock disc with 40 mm thickness failed when design lateral force taken from the extreme load of rotor locking torque was used. However, the safety factor of the optimized rotor lock disc with 60 mm thickness has been improved when the inner radius and the total arc subtended angle are properly identified.
Estimation of Lateral/Directional Static Stability Characteristics of a Turboprop Aircraft at one Engine Inoperative Condition
Authors: Wandini Ratna Ayu , Mulyanto Taufiq , Muhammad Hari
Published: June 2016

Twin engines turboprop aircraft provides the most beneficial solution to meet the needs of short distance flight due to high fuel efficiency [1]. One of the emergency conditions which has to be considered for this type of the aircraft when one engine is out operating or one engine inoperative because it involves the safety of flight. Furthermore, a safe flight with one engine inoperative is regulated by FAR/CASR Part 25 and has to be complied during certification .Stability and control characteristics of a turboprop aircraft will change significantly if one engine inoperative condition occurs during cruise phase. The rudder and/or aileron deflections to counter the yawing and rolling moments due to the thrust of the operating engine must satisfy. Recognizing the importance of that consideration, this research will estimate the stability and control characteristics of lateral/directional in one engine inoperative condition on new turboprop 80-pax aircraft design concept.This paper presents procedures for estimating the lateral/directional static stability characteristics of a 80-pax turboprop aircraft during the conceptual design phase. The size of the rudder and aileron have to be iterated to fullfil the requirements at a condition when one engine is not operative. The rudder and the aileron deflections are estimated as functions of airspeed, roll angle, side slip angle and thrust setting. It will be shown in this paper that the required rudder deflection as well as aileron deflection can satisfy to balance the forces and moments due to asymmetrical thrust condition and the minimum control speed of the aircraft can be maintained as well.
Estimation of Acoustic Energy and Performance Characterization of Acoustic Concentrator
Authors: Thein Min Htike , Lim Kian Meng
Published: June 2016

Among many methods of particle concentration in liquid, acoustic concentrator uses ultrasonic standing wave to concentrate microparticles in liquid. In order to determine its performance on particle concentration, estimation of acoustic energy density inside the concentrator is important since energy density is the main contributing factor in calculating the primary acoustic radiation force acting on the particles. The balance between the primary radiation force and hydrodynamic force acting on the particles inside the acoustic concentrator determine the performance of the acoustic concentrator. Therefore, this study focuses on the measurement of acoustic energy density inside the h-shaped acoustic concentrator and characterization of performance of the concentrator. First, energy density is estimated by curve-fitting the experimental particle position in the ultrasonic field with one-dimensional theoretical position. Second, two-dimensional acoustic and hydrodynamic fields are determined using two-dimensional simulation model in COMSOL Multiphysics. Integrating the governing equation for particle motion in the balance of acoustic and hydrodynamic forces result in the particle trajectory and it is compared with the experimental observation. The results would provide deeper insight into the operation of acoustic concentrator and the detailed phenomenon of particle motions inside the concentrator.
Preparation for Capturing Human Skills during Tooling Tasks Using Redundant Markers and Instrumented Tool
Authors: Gia Hoang Phan , Asif H. , Campolo Domenico
Published: June 2016

In recent years, robots have found extensive applications in automating repetitive, defined, position dependent tasks such as painting and material handling. However, continuous contact type tasks (such as finishing, deburring and grinding) that require both position and force control are still carried out manually by skilled labor. Majorly, because it is difficult to program experienced user skills in a robotic setup without having clear knowledge of underlying model used by the operators. In this paper we present a preparation for capturing human operator’s dynamics using an instrumented hand-held tool and a motion capture setup. We first present the design of an instrumented tool and later present a method for reliably capturing kinematics using redundant markers removing effects of marker occlusions, and effect of gravity caused by the tool's mass. Kinematic information is used for deriving the forces/torques on the tool end effector.
Mathematical Approach for Geometric Error Modeling of Three Axis CNC Vertical Milling Machine
Authors: Kwintarini Widyanti , Wibowo Agung , Martawirya Yatna Yuwana
Published: June 2016

The aim of this paper overviews about to find out the errors that come from three axis CNC vertical milling machine. The errors come from, the CNC milling machine can be modelled into mathematical models and later on these error models will be used to analyse the errors in the measured data. Many errors from CNC machine tools have given significant effects toward the accuracy and repeatability of manufacturing process. There are two error sources come from CNC machine tools such as tool deflection and thermal distortions of machine tool structure. These errors later on will contribute to result in the geometrical deviations of moving axis in CNC vertical milling machine. Geometrical deviations of moving axis such as linear positioning errors, roll, pitch and yaw can be designated as volumetric errors in three axis machine tool. Geometrical deviations of moving axises happen at every axis in three axis CNC vertical milling machine. Geometrical deviations of moving axises in linear and angular movement has the amount of errors up to twenty one errors. Moreover, this geometrical errors play the major role in the total amount of errors and for that particular reason extra attention towards the geometrical deviation errors will be needed along machining process. Each of geometrical error of three axes vertical machining center is modeled using a homogeneous transformation matrix (HTM). The developed mathematical model is used to calculate geometrical errors at each axis and to predict the resultant error vector at the interface of machine tool and workpiece for error compensation.
An Object-Oriented Modelling of Production Scheduling for Flexible Manufacturing System
Authors: Setiawan Ari , Qashmal Luthfan , Wangsaputra Rachmawati , Martawirya Yatna Yuwana , Halim Abdul Hakim
Published: June 2016

This paper presents an object-oriented modelling approach to production scheduling for FMS. The purpose of this study is to prepare a simulation tool to try a method of production scheduling that allocates jobs to the machines and cutting tools in an FMS. This model is developed by using Pharo as the language software for object-oriented programming through UML system design. This model consists of three types of classes. The first type is the Equipment-class, which related to the physical equipment in the FMS, for example machining-centers, cutting tools, pallet stocker, stacker crane. The second type is the Product-class that related to the information how to process the product. This class has sub-class such as process plan, machining operation and required cutting tools. The third class is the Production Planning and Controlling (PPC) class, which related to create the schedule to equipment. The PPC-class has sub-classes such as the daily order or job, job sequence, job allocation on machine and scheduling methods. A numerical example is provided in this paper to show that the object-oriented model for FMS and production scheduling is verified. The FMS consist of four identical machining centers and eight jobs. Each job has a process plan that requires some specific cutting tool types. The method for production scheduling in this model is Shortest Processing Time (SPT). The production scheduling performance is measured in this model.
Maintenance on Job Shop Industry: Review and Analysis
Authors: Budi Harja Herman , Prakosa Tri , Martawirya Yatna Yuwana
Published: June 2016

This paper presents overviews about reliability and maintainability of equipment especially for job-shop manufacturing systems. The job shop industry has the characteristics of a more dynamic production than flow shop industries, where products with a variety of great but small amounts. Its dynamic condition certainly contributes directly to the failure rate and reliability growth of equipment. Therefore, proper maintenance should be done as the reliability improvement. Stages of reliability improvement are reliability modeling, reliability analysis and maintenance optimization. This stage is based on reliability growth of equipment that is indicated the deterioration process of failure components, it can be build from maintenance data history or condition data monitoring.. Cost is often considered in points of a maintenance schedule. This cost was affected by minimizing the negative effects of maintenance and maximizing the benefit of production. The attention at reliability and maintenance optimization is a well researches area until now. This paper presents a brief review of existing reliability and maintenance research. Several reliable methods in this area are discussed and maintenance on job-shop industry as future prospects is investigated. It is shown in this paper that some aspect in the area of maintenance on job-shop industry steel needs to be deeply developed.
An Object-Oriented Modelling for Simulating Workshop Consisted of Machining Center, Pallet Stocker and Stacker Crane
Authors: Hartono Rachmad , Raharno Sri , Martawirya Yatna Yuwana
Published: June 2016

This paper described a methodology to simulate production activities by using object-oriented programming language. Simulation of production to be modeled are the production activities in a workshop. The first step of modelling was defining objects that constitute the main part of a machining center. The main part of machining-center which was being modeled are column spindle, pallet fixture, pallet changer and tool magazine. From these objects can be created a new object that was an object of machining center. The next step was modeling pallet stocker and stacker crane. Pallet Stocker is a container used to store the workpiece or product on the pallet. A stocker crane is a device used to move a workpiece from the pallet stocker to a machining center or vice versa. The final step was modeling a workshop in which there are some machining centers, pallet stocker and stocker crane. Object modeled can be used to simulate a workpiece transfer activity undertaken by stacker crane from the pallet stocker to the machining center.
The Influence of Eco Maintenance on Power Consumption of the Lathe Machines
Authors: Cahyati Sally , Triyono  , Annas M. Sjahrul , Sumpena Ade
Published: June 2016

Generally, a maintenance process of a machine tool is oriented to maintain its reliability and availability in a relation of its productivity. This productivity will make a direct impact on the economic aspect of its plant. Ecomaintenance is a maintenance concept which sees maintenance in a different perspective. There is another effect on a machine that is maintained well on the environmental aspect beside its benefit of technology and economic aspects. If a machine is maintained with a proper maintenance, it will have a performance suitable with its age design condition. A machine with a good maintenance generally has a minimum rate of pollutant and waste which is possible emerging from the machining process. Then, if it uses for a machining process, it will produce a good quality product on its surface roughness and dimension accuracy. The electrical energy consumption of the machine also can be saved. It means that the GHG which usually emerges from the process of electrical energy generation in the power plant can be minimized, also the coal as fuel can be saved. The result of experiment has proven that the machine with bad maintenance will consume the electrical power higher in range 10%-60.81% than the machine with a good maintenance.
Development and Characterization of Porous Biphasic Calcium Phosphate Bone Graft from Natural Biological Origin Raw Material for Biomedical Application
Authors: Herliansyah Muhammad Kusumawan , Anshory Muhammad Irfan
Published: June 2016

Hydroxyapatite (Ca10(PO4)6(OH2), HA has similarities with human bone mineral composition and morphology, bioactive, and non-toxic. However, HA has a weakness in the decay of material, so it can inhibit the growth of new bone tissue. The other materials used as biodegradable bone substitute are Tri Calcium Phosphate (TCP). It has the reception of the body is almost as good as HA but it have fast decay time, so that the material has been discharged before the newly formed tissue. This study aimed to developed a Biphasic Calcium Phosphate (BCP) which is a combination of the properties of HA and TCP, it makes the decay time can be in accordance with the growth of new bone tissue. Calcination method was used in this study. Four groups of bovine bone samples were calcined at four different temperatures ranging from 1000oC to 1300oC using the electric furnace. The heating rate during calcination process was 5oC/minute and dwell time of 2 hours. The calcined bioceramics samples are being examined to determine the characterization of materials. XRD testing to determine the chemical compounds, FTIR performed to determine the ionic bonds that exist in materials and SEM to determine the microstructure of the material calcination results. The current investigation confirms the possibility of producing porous BCP bone graft from porous bovine bone cube, without any important impurities as indicated by XRD and FT-IR techniques. The partially decomposition of HA into TCP was started when bovine bone samples were heated at 1200oC.
Vickers Microhardness Dependence Load and Determining of Tensile Strength of HQ 705 Steel from Microhardness Curves
Authors: Malau Viktor , Arifudin Latif
Published: June 2016

Vickers microindentation hardness test has been applied for a long time to determine the mechanical properties of a small volume of samples. The procedure of this hardness test consists of using a constant load on a rigid indenter and measuring the dimensions of the indenter residual impression (indentation imprint) on the surface of the sample tested after loading and unloading. The objective of this research is to characterize the mechanical properties and material constants of HQ (High Quality) 705 alloy steel mainly its VHN (Vickers Hardness Number) and tensile strength before and after quenching and tempering heat treatments. The characterization is based on Vickers microhardness dependence load curves.Quenching treatment was performed in a furnace by heating the samples at austenite temperature of 850 o C with holding time of two hours and then the samples were rapidly cooled in oil bath. Tempering processes were conducted by heating again the quenching samples to temperatures of 150, 200, 250, 300, 350, 400, 450, 500, 550 and 600 o C with holding time of two hours for each sample. Finally, all samples were slowly cooled in atmospheric temperature. The mechanical properties of samples were characterized by using Vickers microhardness dependence load curves.The results show that VHN (Vickers Hardness Number) depends on indentation load and VHN increases with increment of load for indentation load lower than 5 N. VHN is almost constant for indentation load greater than 5 N. The raw material (without heat treatment) has the VHN and tensile strength of 3413 MPa and 1050.61 MPa respectively and the quenched samples have the VHN and tensile strength of 5407 and 1861 MPa respectively. The Vickers hardness and tensile strength decrease with the increment of tempering temperatures. The higher tempering temperature produces lower hardness and tensile strength. The raw material tensile strength of 1058.8 MPa obtained by tensile test is comparable to its tensile strength of 1050.61 MPa obtained by Vickers indentation. This result indicates that Vickers microindentation is valid to use for evaluating the tensile strength of HQ 705 alloy steel.
Portable Desalination Chamber Utilizing Water Permeable Polyethersulfone (PES) Membrane
Authors: Yanto Restu Andri , Anugrah Anggi Putra , Sriani Tutik , Prihandana Gunawan Setia
Published: June 2016

This paper presents design and fabrication of portable desalination chamber utilizing water permeable polyethersulfone (PES) membrane. The chamber has four stages of desalination process. Each stage has a membrane clamped by filter plate to desalinate sea water and an outlet to qualify the desalinated water from each stage. The chamber works without electrical power, hence desalination process can be carried out in remote areas where electricity source is difficult to find. The water stream is used to test the pumping system of the chamber to pump the water from the water container. The test shows that the pumping system of the chamber is working properly in delivering water to each stage of the chamber without any leakage. The membrane used in each chamber is a modified PES membrane which has high water permeability. Water permeability of the membrane will guarantee that the salt water will permeate easily through the membrane porous during desalination process, hence results in producing fresh water at the final outlet.
Determination of Lead Contamination in Urban Soil, Yogyakarta City, Indonesia
Authors: Zaw Aye Saw Aung , Hendrayana Heru , Eka Putra Doni Prakasa , Sato Tsutomu
Published: June 2016

Lead (Pb) is one of common heavy metal that has been shown to be very useful tracers of environmental pollution. The consequences of urbanization process can cause not only economic growth but also negatively impact on the quality of water and soil. Therefore the objective of this research is to know the potential contamination of lead in soil of urban area. The soil samples were conducted by batch leaching experiment. In surface soil, lead in soil of Pakem area varies from 2.01ppm to 5.13 ppm with average value of 3.02 ppm and Merapi area ranges from 1.84 ppm to 3.41ppm with average value of 2.42 ppm. In urban area, lead varies from 4.18 to 14.88 ppm with average of 9.93 ppm. Lead in urban soil is higher than Pakem and Merapi soil. The potential contamination of lead in urban soil is occurred with respect to urbanization and human activities. The value of lead is shown with the average of 3 ppm for Caturtunggal, Depok District, 6.53 ppm in Mantrijeron District and 9.82 ppm for Kotagede District in Yogyakarta city. The result of lead distribution in Kotagede District is the highest concentrated and it is followed by Mantrijeron District and Caturtunggal, Depok District.
Stress-Distribution around Pin-Loaded Hole for Orthotropic Laminates
Authors: Hidayat Syarif , Hadi Bambang K. , Syamsudin Hendri , Mihradi Sandro
Published: June 2016

Stresses were calculated for orthotropic laminate plate loaded by a frictionless pin in a circular hole of the same diameter. These calculations were based on finite-element analysis for five laminates; 00, [±450]s, [00/900]s,[00/±450]s, and quasi-isotropic [00/±450/900]s. stress distribution, based on nominal bearing stress, were determined for wide ranges of the ratios of width to diameter and edge distance to diameter. Orthotropic had a significant influence on both the magnitude and location of the maximum tensile stress concentration on the boundary of the hole. The laminates with 00 plies developed the peak tensile stress near the ends of the pin-hole contact arc. But the ±450 laminates had peaks where ply fiber were tangent to the hole. The finite width and edge distances strongly influenced the tensile stress concentration. In contrast, the finite widths and edge distances had little effect on bearing stress concentration. For the practical range w/d = 2, the peak tensile stresses were as much as 50 percent larger than the infinite-laminate value. For e/d=1, these stresses were greater 60 percent than infinite-laminate value. In contrast, the finite width and edge distance had little effect on bearing stress concentrations.
Cytokine-Independent Detection of Antigen-Specific Germinal Center T Follicular Helper Cells in Immunized Nonhuman Primates Using a Live Cell Activation-Induced Marker Technique
Authors: Havenar-Daughton Colin , Reiss Samantha M. , Carnathan Diane G. , Wu Jennifer E. , Kendric Kayla , Torrents de la Peña Alba , Kasturi Sudhir Pai , Dan Jennifer M. , Bothwell Marcella , Sanders Rogier W. , Pulendran Bali , Silvestri Guido , Crotty Shane
Published: June 2016

A range of current candidate AIDS vaccine regimens are focused on generating protective HIV-neutralizing Ab responses. Many of these efforts rely on the rhesus macaque animal model. Understanding how protective Ab responses develop and how to increase their efficacy are both major knowledge gaps. Germinal centers (GCs) are the engines of Ab affinity maturation. GC T follicular helper (Tfh) CD4 T cells are required for GCs. Studying vaccine-specific GC Tfh cells after protein immunizations has been challenging, as Ag-specific GC Tfh cells are difficult to identify by conventional intracellular cytokine staining. Cytokine production by GC Tfh cells may be intrinsically limited in comparison with other Th effector cells, as the biological role of a GC Tfh cell is to provide help to individual B cells within the GC, rather than secreting large amounts of cytokines bathing a tissue. To test this idea, we developed a cytokine-independent method to identify Ag-specific GC Tfh cells. RNA sequencing was performed using TCR-stimulated GC Tfh cells to identify candidate markers. Validation experiments determined CD25 (IL-2Rα) and OX40 to be highly upregulated activation-induced markers (AIM) on the surface of GC Tfh cells after stimulation. In comparison with intracellular cytokine staining, the AIM assay identified >10-fold more Ag-specific GC Tfh cells in HIV Env protein–immunized macaques (BG505 SOSIP). CD4 T cells in blood were also studied. In summary, AIM demonstrates that Ag-specific GC Tfh cells are intrinsically stingy producers of cytokines, which is likely an essential part of their biological function.
Development of an SiC Multichip Phase-Leg Module for High-Temperature and High-Frequency Applications
Authors: Chen Zheng , Yao Yiying , Zhang Wenli , Boroyevich Dushan , Ngo Khai , Mattavelli Paolo , Burgos Rolando
Published: June 2016

This article presents a 1,200-V, 120-A silicon carbide metal-oxide-semiconductor field-effect transistor (SiC MOSFET) phase-leg module capable of operating at 200°C ambient temperature. Paralleling six 20-A MOSFET bare dice for each switch, this module outperforms the commercial SiC modules in higher operating temperature and lower package parasitics at a comparable power rating. The module's high-temperature capability is validated through the extensive characterizations of the SiC MOSFET, as well as the careful selections of suitable packaging materials. Particularly, the sealed-step-edge technology is implemented on the direct-bonded-copper substrates to improve the module's thermal cycling lifetime. Though still based on the regular wire-bond structure, the module is able to achieve over 40% reduction in the switching loop inductance compared with a commercial SiC module by optimizing its internal layout. By further embedding decoupling capacitors directly on the substrates, the module also allows SiC MOSFETs to be switched twice faster with only one-third turn-off overvoltages compared with the commercial module.
Monitoring and use of antimycotic (micafungin) for systemic use provided by the pharmacy of Marsala Hospital, Italy
Authors: Venturella Fabio , Tumbarello Maria Cristina , Navarra Laura , Martorana Simona
Published: June 2016

Micafungin is an antimycotic drug and represents an important addition to the available therapies for the treatment of systemic fungal infections. Micafungin is used: in the treatment of invasive candidiasis, oesophageal and prophylaxis of Candida infections. It inhibits, in a non-competitive way, the synthesis of 1,3-β-D-glucan, a component of fungal cell wall and is rapidly distributed into the tissues. It has a high-rate respectful bond with plasma protein, which is independent from the concentration of the drug. It is metabolized through the liver, being not subject to intense metabolic transformations until the excretion. There is no evidence of systemic accumulation after repeated use. The steady-state is reached in 4-5 days. Medical records examined at the pharmacy of Marsala Hospital highlight that, from 01/06/2014 to 01/08/2014, in this hospital 12 vials were used by the hospitalized patients in the Department of Intensive Care: 8 patients between 75 and 83 years old had a body weight (BW) higher than 40 kg; 3 patients between 40 and 60 years of age had a BW higher than 40 kg, and one 17 year-old patient had a BW of 40 kg. Two patients needed a dose increase, while for the other 10 patients the first dose resulted sufficient. Mycamine® was used for the treatment of hypovolemic post-operative shock. The most recorded adverse reactions were anemia, hypokalemia, hypomagnesemia, phlebitis, nausea, liver problems. Given the different weight of the subjects, the dosage was different.
Biodiversity of microcrustaceans (Cladocera, Copepoda) in a lowland river ecosystem
Authors: Karpowicz Maciej
Published: June 2016

This study presents comprehensive research on microcrustacean diversity in different types of aquatic environments in the Upper Narew Valley over five years. A total of 559 samples were analyzed, and 74 species of crustacean zooplankton were identified. Metacyclops planus (Gurney, 1909) is a new species for the fauna of Poland and was found in oxbow lakes and tributary streams. The results of the study suggest that oxbow lakes, with more than 80% of all recorded species, may significantly contribute to the regional biodiversity of floodplain rivers. The highest crustacean community diversity was observed in the semi-lotic oxbow lakes, which emphasizes the role of intermediate disturbance in enhancing biodiversity of water bodies in river valleys. Generally, more “heterogeneous” habitats, such as small oxbow lakes and tributary streams, had higher crustacean species richness. However, a sampling station that was quite “homogeneous”, the Narew River upstream the Siemianówka Reservoir, had high crustacean species richness. The species accumulation curves revealed that approximately 50 - 100 zooplankton samples taken from different environments of river valley are required to establish crustacean species richness. These data could be important for river catchment management and could act as pilot survey data for monitoring plans.
A rib abnormality mimicking pulmonary nodule: a pitfall in the plain chest x-ray
Authors: Akturk Yeliz , GÃ¼nes Serra Ozbal , Hekimoglu Baki
Published: June 2016

The ribs show a wide range of normal and pathologic radiographic appearences as well as congenital variations. Intrathoracic ribs are isolated and rare anomalies. They are usually super-numerary, more often right-sided, and involve the middle part of the thorax. We describe a case with intrathorasic rib abnormality mimicking a peripheral metastatic lung nodule in the plain chest x-ray and emphasize the use of coronal and sagittal reformatted images in thorasic imaging.Â  Utilisation of multiplanar reformatted images in chest computerised tomography increase diagnostic quality.
Multum non multa: airway distensibility by forced oscillations
Authors: Mermigkis Charalampos , Schiza Sophia E. , Panagou Panagiotis
Published: June 2016

Airway distensibility although appears to be unaffected by airway smooth muscle tone probably related to airway remodelling, after bronchodilator treatment is significantly increased in subjects with asthma. We assessed airway distensibity and its first moment derivative in two patients with mild intermittent asthma and normal spirometry. The increase in airway distensibility after bronchodilation measured at the tidal volume range during quiet breathing by forced oscillations was not accompanied by a change in its first moment, while the latter showed a significant increase in a second patient after anti-inflammatory treatment. It appears that airway distensibility is sensitive to reduction of bronchial smooth muscle tone after bronchodilation, but in addition its first moment might provide information on a change of both bronchial smooth muscle tone and small airways inflammation.
Endobronchial Watanabe Spigot in the treatment of bronchobiliary fistula
Authors: Ã–zdemir Cengiz , SÃ¶kÃ¼cÃ¼ Sinem Nedime , AkbaÅŸ AyÅŸegÃ¼l , Altay Sezin , Karasulu Ahmet Levent , Dalar Levent
Published: June 2016

Bronchobiliary fistula (BBF) is a rare condition in which an abnormal communication exists between the bile ducts and the bronchial tree. Malignancy is the most common etiology of BBF, although many others are possible. A 74-year-old male patient with an inoperable Klatskin tumor presented with a complaint of yellow-green sputum and cough; the patient underwent fiber-optic bronchoscopy based on a preliminary diagnosis of bronchobiliary fistula. Using fiber-optic rigid bronchoscopy, the laterobasal segment of the lower right lung lobe was occluded using three pieces of 5-mm Endobronchial Watanabe Spigot. Bile drainage subsequently ceased. A bronchoscopic approach provides an alternative option for BBF treatment, particularly in patients who choose not to undergo surgery, or for whom surgery is not an option due to their underlying general condition.
A review of the classification of nonstrabismic binocular vision anomalies
Authors: Darko-Takyi Charles , Khan Naimah Ebrahim , Nirghin Urvashni
Published: June 2016

There are conflicting and confusing ideas in literature on the different types of accommodative and vergence anomalies as different authors turn to classify them differently. This paper sought to review literature on the different classifications and types of nonstrabismic binocular vision anomalies and harmonize these classifications. Search engines, namely Google scholar, Medline, Cinahl and Francis databases, were used to review literature on the classification of accommodative and vergence dysfunctions using keywords like binocular vision dysfunctions, classification of nonstrabismic binocular vision disorders or anomalies, accommodative disorders/anomalies classification and vergence disorders/anomalies classifications, and included works that described these anomalies. Nonstrabismic binocular vision anomalies are classified as accommodative and vergence anomalies. There are three different major types of accommodative anomalies, namely accommodative insufficiency, accommodative infacility (accommodative inertia), and accommodative excess (accommodative spasm), and seven different types of vergence anomalies (convergence insufficiency, convergence excess, divergence insufficiency, divergence excess, basic esophoria, basic exophoria and fusional vergence dysfunctions), which are functional in origin. Functionally, there is a commonly reported interaction between accommodative and convergence insufficiency referred to as pseudoconvergence insufficiency. Accommodative paralysis (subtype of accommodative insufficiency) and vergence anomalies – i.e., convergence paralysis, convergence spasm and divergence paralysis – are non-functional in origin with underlying systemic disease etiologies. Systemic convergence insufficiency, associated with subnormal accommodation, is a non-functional interaction between the accommodative and convergence insufficiency. The classification of nonstrabismic binocular vision anomalies is based on the description of the clinical signs and the underlying etiology either functional or non-functional in origin. Proper diagnosis and management involves investigation of the underlying etiology in addition to the battery of binocular vision test procedures.
Systemic lupus erythematosus presenting as fulminant lupus pneumonitis: a rare case report
Authors: Aggarwal H.K. , Jain D. , Mittal A. , Rao A. , Yadav R.K. , Jain P.
Published: June 2016

We report a case of 19 year-old female patient diagnosed as systemic lupus erythematosus (SLE) presented with fever and diffuse cutaneous lesions. During the hospital stay she had acute pneumonia, pleural effusion and respiratory failure, which required intensive care unit (ICU) care and mechanical ventilator support. A fulminant course of the disease, decreased values of complement levels and positive antinuclear antibodies (ANA) in pleural fluid and repeated negative sputum for acid-fast bacillus, blood cultures enabled diagnosis of fulminant lupus pneumonitis. Fulminant lupus pneumonitis is a rare but potentially life threatening complication of SLE. Management requires involvement of multiple specialties and rigorous efforts in reviving the patient.
Gitelman syndrome disclosed by calcium pyrophosphate deposition disease: early diagnosis by ultrasonographic study
Authors: Zabotti A. , Della Siega P. , Picco L. , Quartuccio L. , Bassetti M. , De Vita S.
Published: June 2016

Gitelman’s syndrome is a rare autosomal-recessive tubular disorder characterized by hypomagnesemia and hypocalciuria associated to hypokalemia. The clinical spectrum is wide and usually characterized by chronic fatigue, cramps, muscle weakness and paresthesiae. We describe a case of a 43 year-old male patient with early onset of knee arthritis and no other symptoms. Ultrasound revealed diffuse and confluent hyperechoic deposits in cartilage, fibrocartilage of the menisci and synovium and calcium pyrophosphate crystals were observed in the synovial fluid of the knee. The concomitant presence of hypomagnesemia, hypocalciuria and hypokalemia made clear the diagnosis of Gitelman’s syndrome associated with chondrocalcinosis.
Higher order aberrations of the eye: Part one
Authors: Oberholzer Marsha , Gillan Wayne D.H. , Rubin Alan
Published: June 2016

This article is the first in a series of two articles that provide a comprehensive literature review of higher order aberrations (HOAs) of the eye. The present article mainly explains the general principles of such HOAs as well as HOAs of importance, and the measuring apparatus used to measure HOAs of the eye. The second article in the series discusses factors contributing to variable results in measurements of HOAs of the eye.Keywords: Higher order aberrations; wavefront aberrations; aberrometer
Role of Biomarkers in the Diagnosis, Risk Assessment, and Management of Pulmonary Hypertension
Authors: Rameh Vanessa , Kossaify Antoine
Published: June 2016

Pulmonary hypertension is a severe and debilitating disease with no definite cure, and the domain of targeted therapies is a promising field for better management of this severe condition. The disease comprises pulmonary arterial remodeling, hypoxia, endothelial dysfunction, and inflammation, with subsequent organ damage including right heart and liver dysfunction. Biomarkers have a valuable role at different levels of the disease, from diagnosis to risk assessment and management, in order to decrease the burden of the disease in terms of both morbidity and mortality.
A case study of the radiative effect of aerosols over Europe: EUCAARI-LONGREX
Authors: Esteve Anna R. , Highwood Eleanor J. , Ryder Claire L.
Published: June 2016

Abstract. The radiative effect of anthropogenic aerosols over Europe during the 2008 European Integrated Project on Aerosol Cloud Climate and Air Quality Interactions Long Range Experiment (EUCAARI-LONGREX) campaign has been calculated using measurements collected by the Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 aircraft and radiative transfer modelling. The aircraft sampled anthropogenically perturbed air masses across north-western Europe under anticyclonic conditions with aerosol optical depths ranging from 0.047 to 0.357. For one specially designed “radiative closure” flight, simulated irradiances have been compared to radiation measurements for a case of aged European aerosol in order to explore the validity of model assumptions and the degree of radiative closure that can be attained given the spatial and temporal variability of the observations and their measurement uncertainties. Secondly, the diurnally averaged aerosol radiative effect throughout EUCAARI-LONGREX has been calculated. The surface radiative effect ranged between −3.9 and −22.8 W m−2 (mean −11 ± 5 W m−2), whilst top-of-the-atmosphere (TOA) values were between −2.1 and −12.0 W m−2 (mean −5 ± 3 W m−2). We have quantified the uncertainties in our calculations due to the way in which aerosols and other parameters are represented in a radiative transfer model. The largest uncertainty in the aerosol radiative effect at both the surface and the TOA comes from the spectral resolution of the information used in the radiative transfer model (∼ 17 %) and the aerosol description (composition and size distribution) used in the Mie calculations of the aerosol optical properties included in the radiative transfer model (∼ 7 %). The aerosol radiative effect at the TOA is also highly sensitive to the surface albedo (∼ 12 %).
Total atmospheric mercury deposition in forested areas in South Korea
Authors: Han Jin-Su , Seo Yong-Seok , Kim Moon-Kyung , Holsen Thomas M. , Yi Seung-Muk
Published: June 2016

Abstract. In this study, mercury (Hg) was sampled weekly in dry and wet deposition and throughfall and monthly in litterfall, and as it was volatilized from soil from August 2008 to February 2010 to identify the factors influencing the amount of atmospheric Hg deposited to forested areas in a temperate deciduous forest in South Korea. For this location there was no significant correlation between the estimated monthly dry deposition flux (litterfall + throughfall – wet deposition) (6.7 µg m−2 yr−1) and directly measured dry deposition (9.9 µg m−2 yr−1) likely due primarily to Hg losses from the litterfall collector. Dry deposition fluxes in cold seasons (fall and winter) were lower than in warmer seasons (spring and summer). The volume-weighted mean (VWM) Hg concentrations in both precipitation and throughfall were highest in winter, likely due to increased scavenging by snow events. Since South Korea experiences abundant rainfall in summer, VWM Hg concentrations in summer were lower than in other seasons. Litterfall fluxes were highest in the late fall to early winter, when leaves were dropped from the trees (September to November). The cumulative annual Hg emission flux from soil was 6.8 µg m−2 yr−1. Based on these data, the yearly deposition fluxes of Hg calculated using two input approaches (wet deposition + dry deposition or throughfall + litterfall) were 6.8 and 3.6 µg m−2 yr−1, respectively. This is the first reported study which measured the amount of atmospheric Hg deposited to forested areas in South Korea, and thus our results provide useful information to compare against data related to Hg fate and transport in this part of the world.