bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Oxidation Resistance of Tool Materials for Machining Superalloy
Authors: Wang Teng Da , Liu Er Liang , Li Zhen
Published: January 2016

The high temperature oxidation phenomenon will occur on the tool-workpiece contact area when machining the superalloy. Two kinds of cemented carbide tools (YG6X, YG8) are selected, the coated carbide tool and coated ceramic tool which are suitable for machining superalloy are selected. The resistance furnace is used for heating tool material, and the oxidation resistance experiments are carried out. The results show that: WC which is included in the cemented carbide tool is oxidized to WO3 and the Co is oxidized to Co3O4, Ti which is included in the coated carbide tool is oxidized to TiO2. The grain of the tool is smaller, the oxidation resistance is better. The oxidation resistant of coated carbide tool is better than the non-coated tools. The coated ceramic tool is not substantially oxidized in high temperature situation. The merits order of the oxidation resistant properties is that: coated ceramic tool>coated carbide tool > YG6X>YG8.
Experimental Research on Chemical Mechanical Sharpening of CVD Diamond Micro Tool
Authors: Xia Yi , Hao Xiu Qing , Li Liang , He Ning
Published: January 2016

This Research is Focused on the Chemical Mechanical Sharpening of CVD Diamond Micro Tool, which has High Strength and Good Wear Resistance. the Diamond Grinding Wheels were Usually Used for Sharpening, but this Method could Not get High Quality Surface of the Diamond Efficiently and Small Cutting Edge Radius. in Order to Seek a Better Mode for Sharpening, the Copper Based Tungsten Carbide Disc and Abrasive were Used for Grinding. for Better Understanding the Effects of Different Parameters on the Grinding Process and Optimizing them, the Orthogonal Method was Used to Design the Experiments. Grinding Direction, Feed Rate and the Grinding Velocity were Investigated to Obtain Sharper Cutting Edge and Smooth Flank Face. Analysis of Range was Also Introduced to Evaluate the Contribution of each Parameter in Orthogonal Experiment. the Results Showed that down Grinding, Medium Feed Rate and Low Velocity could Achieve a Better Sharpening Result.
Application of Different Cooling Strategies in Drilling of Metal Matrix Composite (MMC)
Authors: Sadik M. Ibrahim , Grenmyr Gustav
Published: January 2016

Conventional cutting fluids are known for being expensive, polluting and a non-sustainable part of modern manufacturing processes. Global industrial trends are leaning towards environmental and health friendly technologies. CO2 cooling is an innovative and sustainable method, capable of replacing conventional oil-based cutting fluids under various conditions. The current study intends to cover the indexable insert drilling of aluminium-silicon carbide (Al-SiC) metal matrix composite (MMC) using different diamond coated carbide inserts. Al-SiC composite containing 20% wt. of SiC was used as workpiece material under different cooling strategies. Response Surface Methodology (RSM) and SEM analysis were incorporated to evaluate the tool performance and to understand the wear development in drilling of MMC. Performance tests were carried out at various cutting data and cooling strategies (external CO2, external emulsion, internal CO2 and internal emulsion) in order to study the output in terms of tool life, surface finish and diameter difference of the holes. The results revealed an advantage in the favour of CO2 cooling concerning tool life, precision and surface finish. Drilling with internal supply of CO2 significantly improves the tool life. The internal supply of CO2 generated the best precision and surface finish compared to the other cooling strategies. The test results clearly indicate that the tool failure for internal CO2 is governed by the flaking of the diamond coating in contrast to a combination of flank wear and flaking for emulsion. The results from the external cooling strategy show that there is no significant difference between emulsion and CO2 while the internal cooling strategy shows that CO2 provides the best results. Since the shape and the surface of the hole are generated by the cutting edge of the periphery insert, the wear development on the periphery insert is the main factor which governs the tool life, surface finish and the diameter difference. This can be explained by the internal CO2 strategy that protects the periphery insert.
Research on the Tool Wear Mechanism of Cemented Carbide Ball End Mill Machining Titanium Alloy
Authors: Zhang Yu Hua , Yang Shu Cai , Feng Chuang
Published: January 2016

In order to achieve the high efficiency machining of titanium, the cutting force model is verified through the cutting experimental platform in machining cant and curved surface with ball end milling. And then the influence of cutting parameters and surface curvature on cutting force and tool wear are investigated. Finally, the prediction model of tool wear is established based on the orthogonal test and the least square method. This study proposes that the tool wear and each tooth feeding have a major impact on cutting force and that the convex surface from a small curvature to larger and the concave surface from a large curvature to smaller can effectively improve the life of tool in machining curved surface.
Lightweight Design of the Welded Beam of Machining Center Based on Topology Optimization
Authors: Sun Qin , Li Zuo Li , Yu Hui , Liu Yang , Zhang Jin Sheng
Published: January 2016

From the perspective of statics, the deformation of welded beam under the action of gravity and cutting force was studied in the paper. During the actual machining process, vibration of welded beam and even the machine can be caused due to the change of cutting condition and interference from the outside. To avoid the natural frequency, and prevent the occurrence of resonance phenomena, welded beam modal was further analyzed; the first six natural frequencies and mode shapes of the beam were achieved. Statics and modal analysis are the basis of lightweight design of the welded beam based on topology optimization. The topology optimization model of maximum stiffness design and eigenvalue problem structural dynamics was established. Finite element model of beam and its components was established in hypermesh, and the optimization objective function, constraint function and boundary conditions were also set. Compared with the structure before optimization, the weight of the beam was reduced 10%, the lightweight design of the welded beam was achieved and the comprehensive performance of the beam was significantly improved.
Experimental Research of Milling Force and Cutting Temperature of TB2 Titanium Alloy in Liquid Nitrogen Cooling
Authors: Liu Jing Jing , Chen Chong , Yang Yin Fei , Li Liang , Zhao Wei
Published: January 2016

Titanium alloy is becoming increasingly employed in the aerospace industries due to its good mechanical and chemical properties. As a typical difficult-to-machine material, there are problems of fast tool wear and poor stability of the processing quality in the machining process. Therefore, experiments of high feed milling of TB2 titanium alloy in liquid nitrogen cooling were carried out to measure the cutting force and the cutting temperature. The experimental results showed that under some parameters, liquid nitrogen could decrease the cutting force and cutting temperature in comparison with dry cutting. What’s more, the tool life as well as the surface quality was improved.
Parameter Analysis of Placement Function for the Rectangular Packing Problem Based on GA
Authors: Zhu Yan Hua
Published: January 2016

Rectangle part is the foundation of irregular part layout, about which domestic and overseas scholars have studied a lot and have put forward many algorithms. Based on a careful study of these algorithms in the paper, it is determined to solve the rectangle packing problem with genetic algorithm analysis. Different from the formerly used the genetic algorithm optimization layout, the algorithm of this paper stresses optimization localization rule in order to solve layout problem with the advantages of global searching ability of genetic algorithm. This algorithm sets the utilization ratio of the maximum area of capacity as the goal, after confirming the priority of deposition sequence of rectangle, in view of the locating rule of rectangle packing, based on feasible region and by introducing the method of attractive factors, optimizing the calculation for each parameter of placement function by utilizing genetic algorithm.Positioning function of the structure of this paper by changing the parameter value can cover the previous golden horn strategy, the lower left corner strategy, down the steps such as positioning method. Use VC programming to realize automatic two dimensional rectangular layout systems, the algorithm and example verification, the precision of parameter on the result of layout, the number of attractor for layout results, and the influence of parameter values for different rectangular piece of regularity. According to different rectangular block configuration, layout scheme can be better and faster.
Study on Plunge Milling Cutter Design with Finite Element Analysis
Authors: Zhai Yuan Sheng , Song Hong Li , Hu Jing Shu
Published: January 2016

Plunge milling cutter withstanding greater loads in heavy milling can cause tool breakage, cutting vibration, even chatter. Firstly, geometric model of plunge milling cutter on various combinations of axial rake angle and radial rake angle are established. Secondly, with combination different axial rake angle and radial rake angle of plunge milling cutter under static load, the amount of deformation plunge milling cutter are calculated by finite element analysis. Finally, the plunge milling cutter first six natural frequencies are given in plunge milling cutter modal analysis with finite element analysis. The results show that minimum total deformation of plunge milling cutter is given with the axial rake angle 5° and radial rake angle-5 ° of the cutter and when the tool working at frequencies up to 10012HZ has caused vibration within the XY plane.
Heat Transfer Model for Pulse Laser Assisted Machining of ZrO2
Authors: Lu Huan , Wang Shu Long , He Ning , Li Liang , Hao Xiu Qing
Published: January 2016

Laser assisted machining (LAM) is one important solution for machining difficult-to-machine materials. The heat transfer model of quasi steady state in laser assisted micro machining is built, and the simulation software for temperature distribution measurement is developed based on MATLAB. The simulated temperature distribution of the ZrO2 ceramic heated by pulse laser shows a good agreement of tendency with the corresponding experimental results through the infrared temperature measurement method, while the simulated temperature is consistently overestimated. This difference maybe results from the neglect of the heat loss caused by the heat radiation and the heat convection in the model. The proposed model in this paper could provide reference for the selection of optimal process parameters and improve the machining quality, which are closely related to the temperature distribution.
Finite Element Simulation of High Speed Machining of Ti6Al4V Alloy and the Corresponding Experimental Study
Authors: Meng Long Hui
Published: January 2016

Finite element simulation of high speed machining of Ti6Al4V alloy was carried out based on the software of Abaqus. The Johnson-Cook constitutive model was chosen for the material of Ti6Al4V, the parameters of the model were obtained through the SHPB (Split Hopkinson Pressure Bar) experiment. The similarity of the chips obtained from the simulation and that obtained from the experiment indicated that the parameters of the Johnson-Cook constitutive model for Ti6Al4V alloy were reliable. Different cutting parameters and different tool geometric parameters were used in the simulations to find out their effects to the simulation results. Also a comparison was made between the results got form the simulations results and the experimental results, a good agreement between them indicated that the finite element simulation of high speed machining of Ti6Al4V is reliable, so it can be concluded that the finite element simulations of high speed machining can be widely used in practice to study the more about the machining process and reduce the experimental expenses.
Finite Element Simulation of Ultrasonic Incremental Forming
Authors: Li P.Y. , Liu Qiang , An Wu Run , Li Shu Juan
Published: January 2016

This paper briefly describes the principle of the ultrasonic single point incremental forming of the sheet metal. In which we established the finite element model and finished the finite simulation with ABAQUS. According to the simulation result, we analyzed the influence law of vibration frequency of the axis on the distribution of the stress and strain of the sheet metal, the thickness, and the axial force in the process of ultrasonic single point incremental forming of the sheet metal. The result shows that the influence on the stress and thickness of the sheet metal is minimal, and the influence on the strain follows the law of cosines in which the strain is minimum when the vibration frequency is equal to 15kHZ.The influence on the axial force is that when the frequency is f=0kHz～40kHz the axial force decreases with the increase of the frequency. However, the axial force increased dramatically with the increase of the frequency when the frequency is above 40kHz.
Microstructural Effect on Crack Propagation Behavior of Ceramic Tool Materials via Cohesive Zone Modeling
Authors: Li Zuo Li , Zhao Jun , Wang Fu Zeng , Li An Hai , Tian Xian Hua
Published: January 2016

A systematic and parametric study of the effect of grain size and volume fraction of secondary phase on crack propagation behavior of Al2O3 based ceramic tool materials was carried out. Two-dimensional centroid V toughness oronoi tessellations were generated with random grain orientations. Cohesive Zone Method (CZM) was utilized to simulate crack propagation behavior. Zero-thickness cohesive elements were embedded on grain boundaries and inside grains. Crack initiation and propagation in ceramic tool materials microstructure were simulated without predefined crack. Simulation results revealed that crack initiated at the maximum stress position and propagated along the direction perpendicular to external load. Decreasing the grain size or increasing the volume fraction of secondary phase can improve the fracture stress of Al2O3 ceramic tool materials.
Orthogonal Variable Thickness Cutting Modeling of Surface Milling and Physical Fields Simulation
Authors: Zhang Wei , Du Chang Jian , Cheng Xiao Liang , He Feng Shun
Published: January 2016

When milling the complex surface with the ball-end milling cutter, the cutting thickness always changes in ball-end milling process. At present, many milling models are actually simplified with unchanged cutting thickness, which ignores the ball-end milling cutting with complex tool-work piece relationship. According to the characteristics of the ball-end milling, orthogonal variable thickness cutting model is established based on the study of three-dimensional contact relationship of tool-work piece. The simulation of the stress field and the temperature field in hardened steel Cr12MoV orthogonal variable thickness cutting process is conducted, and comparative analysis of stress and temperature field distribution of high-speed milling and conventional milling is made. The cutting model of orthogonal variable thickness cutting can reflect the characteristics of surface milling accurately, which can be further used in the study of changing characteristics of physical fields and the optimization of cutting and tool parameters to improve the machining efficiency and quality.
Study on the High Speed Cutting Experiment of Micro Deformation Zone Based on the Theory of Dislocation
Authors: Fu Xiu Li , An Zeng Hui , Pan Yan An , Lin Wen Xing , Qiao Yang
Published: January 2016

The dislocation theory is applied to study plastic deformation in high-speed cutting to show the formation characteristics of the micro scale deformation zone in high-speed cutting. Through the quick stoppage experiment of aluminum alloy 7050-T7451 in high-speed cutting and the further research of inclined cutting chip formation mechanism and deformation of shear zone in plastic mechanics and dislocation theory respect .The stress, the strain state and microstructure near the front edge of the rake face edge is analyzed. Effective flow stress, effective strain distribution and variation in shear deformation zone is simulated. According to the experimental and simulation results and from the microscopic respect, the traditional cutting deformation zone is reclassified, the deformation zone of the front edge and dislocations compression zone is increased to achieve a more accurate description of the deformation zone and provide a theoretical basis for the study of high-speed cutting deformation mechanism.
The Design of Automatic System for the Calibration of Testing Temperature Cutter with Thin Film Thermocouple
Authors: Cui Yun Xian , Qi Yang , Guo Li Ming , Zhang Qi Xiang , Jia Ying
Published: January 2016

In order to get an accurate online measurement for the transient cutting temperature in precision, in an ultra-precision cutting process,a temperature measuring device should be assessed whether it can obtain precise magnitude readings and variables of which are measured accurately. The just produced thin-film thermocouple used to measure tool cutting temperature must be correctly calibrated[3,4] , however traditional calibrating process problems rely on manual operation completely with lots of problems such as low efficiency, high labor intensity and large error. this paper proposes an automatic calibration system for thin-film thermocouple by using temperature measuring furnace, data acquisition card and computer-based software. The system makes an automatically and intelligently calibration process. By using a high-precision data acquisition card and precision amplifier circuit, eight thermocouples can be calibrated at the same time automatically which effectively shortens the calibration time and improves the accuracy. Use temperature metering furnace to control data acquisition. Secondary error from using standard thermocouple and other methods to collect the temperature metering furnace real-time temperature is eliminated. The system software modules consist of data reading, data processing, data display, database operation, data query and report generation module. The experimental results show that nonlinear fitting error is less than 0.6% within the temperature measurement range, which meets the requirement of the secondary precision of thermocouple error. This paper intends to provide a new calibration method for thermocouple temperature measurement tool development and production[7].
Time Dependent Behavior Analysis of Inconel 718 in High Speed Grinding Process
Authors: Zhi Geng , Li Xue Kun , Rong Yi Ming
Published: January 2016

The time dependent behavior of grinding is expressed as the change of process output measures as a function of time during grinding. Although the wheel capability will be restored by dressing, the time dependent behavior of grinding during one dressing skip is determinant on the grinding quality variation in terms of surface integrity and workpiece geometric accuracy. Therefore, understanding of grinding time dependent behavior in relation with the wheel-workpiece microscopic interaction is critical for wheel and process development to achieve stable grinding processes. In this paper, the high speed grinding of inconel 718 with cBN grinding wheels is carried out. The time dependent behavior is recorded to represent the characteristic features. And the microscopic wheel topography is measured under SEM throughout the whole grinding process so as to reveal the root cause for the time dependent behavior and its impact on the workpiece quality variation.
Chip Formation of S790 Hardned Steel under High Speed Dry Milling Condition
Authors: Yu Dong Hai , Wang Hao , Wang Cheng Yong , Yuan Yao Hui , Ding Feng
Published: January 2016

In this paper, the chip morphologies and sizes of hardened PM steel S790 (68 HRC) using four types coated end mills (TiAlN TiCrAlN TiSiN and TiAlSiN) under different cutting parameters in dry milling condition were studied. During the process of high speed milling hardened steel S790, the chip morphologies change from continuous strip to sawtooth with the increase of cutting speeds. When cutting speed reaches 100 m/min, obvious shear slip occoured on the top surface of the chips, which are formed by multilayer metal unit piled by shear slip plane segmentation. The bottom of the chips, which squeeze and slid with rake face of end mills, show shiny smooth surface. TiAlSiN and TiSiN coatings are more suitable for high speed milling than TiAlN and TiCrAlN coatings. With the increase of cutting parameters such as cutting speed, feed rate and axial cutting depth, the chips morphology of S790 change from continuous strips to trapezoidal and triangle sawtooth, and the chips trend easy separation.
Time Domain Simulation of Milling Chatter Stability
Authors: Ma Ying Chao , Wan Min , Zhang Wei Hong
Published: January 2016

In this paper, time domain simulation has been carried out to study the chatter stability of milling process. Dynamic chip thickness is calculated by analyzing the kinematics of the cutter, and thus dynamic governing equation revealing the dynamic behaviors between the cutter and workpiece is established. Solving framework is constructed by using the Simulink module and S-Function of Matlab software, and dynamic deflection is achieved with the four-order Runge-Kutta algorithm. With the simulated cutting forces, a criterion for the construction of the stability lobe is suggested. At the same time, algorithm for the prediction of the surface topography involving the dynamic response of the machining system is developed.
Human Host Defense Cathelicidin Peptide LL-37 Enhances the Lipopolysaccharide Uptake by Liver Sinusoidal Endothelial Cells without Cell Activation
Authors: Suzuki Kaori , Murakami Taisuke , Hu Zhongshuang , Tamura Hiroshi , Kuwahara-Arai Kyoko , Iba Toshiaki , Nagaoka Isao
Published: January 2016

The liver is a major organ that removes waste substances from the blood, and liver sinusoidal endothelial cells (LSECs) are professional scavenger cells, which incorporate and degrade various endogenous and exogenous molecules including pathogenic factor LPS. Mammalian cells express a number of peptide antibiotics that function as effectors in the innate host defense systems. LL-37, a human cathelicidin antimicrobial peptide, has a potent LPS-neutralizing activity and exhibits protective actions on various infection models. However, the effect of LL-37 on the LPS clearance has not been clarified. In this study, to further understand the host-protective mechanism of LL-37, we evaluated the effect of LL-37 on the LPS clearance in vitro. LL-37 enhanced the LPS uptake by human LSECs. Of interest, LL-37 was similarly incorporated into LSECs both in the presence and the absence of LPS, and the incorporated LPS and LL-37 were colocalized in LSECs. Importantly, the uptake of LPS and LL-37 was inhibited by endocytosis inhibitors, heparan sulfate proteoglycan analogs, and glycosaminoglycan lyase treatment of the cells. Moreover, the uptake of LL-37-LPS did not activate TLR4 signaling in both MyD88-dependent and -independent pathways. In addition, the incorporated LL-37-LPS was likely transported to the lysosomes in LSECs. Together these observations suggest that LL-37 enhances the LPS uptake by LSECs via endocytosis through the complex formation with LPS and the interaction with cell-surface heparan sulfate proteoglycans, thereby facilitating the intracellular incorporation and degradation of LPS without cell activation. In this article, we propose a novel function of LL-37 in enhancing LPS clearance.
Image Gently: A campaign to promote radiation protection for children worldwide
Authors: Applegate Kimberly
Published: January 2016

With the goal of raising awareness and developing stakeholder educational tools for the appropriate imaging of children, the Image Gently campaign was launched in 2007. This campaign is a product of a multidisciplinary alliance with international representation which now numbers nearly 100 medical and dental professional societies and organisations, and includes regulatory organisations. The alliance focuses on increasing awareness and developing education materials that support the protection of children worldwide from unnecessary radiation in medicine. The alliance members work with agencies and regulatory bodies to improve standards and measures that are specific to children. The campaign has produced open source modules for all stakeholders regarding CT, fluoroscopy, nuclear medicine, interventional radiology, digital radiography and dental imaging. The philosophy of the Image Gently steering committee is to collaborate, to share information freely, to keep messaging simple and to commit to lifelong learning. Many healthcare practitioners may not understand how to decrease children’s radiation exposure; the goal of Image Gently is to increase all stakeholders’ understanding of both the benefits and the risks and to encourage radiation reduction strategies. This article summarises the rationale and goals of the global campaign to date.
The clinical development process for a novel preventive vaccine
Authors: Singh K , Mehta S
Published: January 2016

Each novel vaccine candidate needs to be evaluated for safety, immunogenicity, and protective efficacy in humans before it is licensed for use. After initial safety evaluation in healthy adults, each vaccine candidate follows a unique development path. This article on clinical development gives an overview on the development path based on the expectations of various guidelines issued by the World Health Organization (WHO), the European Medicines Agency (EMA), and the United States Food and Drug Administration (USFDA). The manuscript describes the objectives, study populations, study designs, study site, and outcome(s) of each phase (Phase I-III) of a clinical trial. Examples from the clinical development of a malaria vaccine candidate, a rotavirus vaccine, and two vaccines approved for human papillomavirus (HPV) have also been discussed. The article also tabulates relevant guidelines, which can be referred to while drafting the development path of a novel vaccine candidate.
Human epidermal growth factor receptor 2/neu overexpression in urothelial carcinoma of the bladder and its prognostic significance: Is it worth hype?
Authors: Kumar Santosh , Prajapati Omprakash , Vaiphei Kim , Parmar Kalpesh Mahesh , Sriharsha A. S. , Singh S.K
Published: January 2016

Aims: In urothelial tumors of the urinary bladder, human epidermal growth factor receptor 2 (HER-2)/neu expression has been reported over 10 years, but there is no clear correlation between prognosis and recurrence rate. The present study evaluates prognostic implication of HER-2/neu expression. Subjects and Methods: In this study, 100 formalin-fixed paraffin-embedded specimens of primary transitional cell carcinoma of the bladder were processed. HER-2/neu monoclonal antibody immunohistochemistry staining procedure used for the study. Results: A total of 70 (70%) patients were positive for overexpression of HER-2/neu. HER-2/neu was positive in patients with 42 (70%) superficial tumor, 28 (70%) muscle invasive tumor, 41 (75.9%) high-grade tumor, 29 (63%) low grade tumor, 31 (68.9%) recurrent tumor, and 6 (66.6%) had positive lymph nodes. Conclusions: Human epidermal growth factor receptor 2/neu over expression was not correlated with the tumor stage, lymphnode metastasis or recurrence of the disease. HER-2/neu overexpression was statistically insignificantly correlated with the differentiation grade (P < 0.161) as compared to previous studies. Future studies on HER-2 expression with chemo-sensitivity and efficacy of HER-2-targeted therapies in urothelial carcinomas is needed.
Fertility preservation in young patients with cancer
Authors: Suhag Virender , Sunita B. S. , Sarin Arti , Singh A. K. , S. Dashottar
Published: January 2016

Infertility can arise as a consequence of treatment of oncological conditions. The parallel and continued improvement in both the management of oncology and fertility cases in recent times has brought to the forefront the potential for fertility preservation in patients being treated for cancer. Many survivors will maintain their reproductive potential after the successful completion of treatment for cancer. However total body irradiation, radiation to the gonads, and certain high dose chemotherapy regimens can place women at risk for acute ovarian failure or premature menopause and men at risk for temporary or permanent azoospermia. Providing information about risk of infertility and possible interventions to maintain reproductive potential are critical for the adolescent and young adult population at the time of diagnosis. There are established means of preserving fertility before cancer treatment; specifically, sperm cryopreservation for men and in vitro fertilization and embryo cryopreservation for women. Several innovative techniques are being actively investigated, including oocyte and ovarian follicle cryopreservation, ovarian tissue transplantation, and in vitro follicle maturation, which may expand the number of fertility preservation choices for young cancer patients. Fertility preservation may also require some modification of cancer therapy; thus, patients’ wishes regarding future fertility and available fertility preservation alternatives should be discussed before initiation of therapy.
Human Trypanosomiasis in the Eastern Plains of Colombia: New Transmission Scenario
Authors: Angulo-Silva Victor Manuel , Castellanos-Domínguez Yeny Zulay , Flórez-Martínez Mónica , Esteban-Adarme Lyda , Pérez-Mancipe William , Farfán-García Ana Elvira , Luna-Marín Katherine Paola
Published: January 2016

Characteristics of Trypanosoma cruzi infection were studied in a rural area of the eastern plains of Colombia. Using enzyme-linked immunosorbent assay and indirect fluorescent-antibody tests, the infection was determined in 11.6% of the inhabitants of 142 dwellings. During 6 months of community surveillance, in 42.3% dwellings, 609 triatomines were collected (597 Rhodnius prolixus and seven, three, one, and one of Panstrongylus geniculatus, Psammolestes arturi, Eratyrus mucronatus, and Triatoma maculata, respectively). Rhodnius prolixus was found in 80% peridomiciliary Attalea butyracea palms examined with baited traps, and its infection with T. cruzi was 30% and 38.5% in dwellings and palms, respectively. Trypanosoma cruzi was isolated in five of 35 triatomines and in one of 24 dogs. The blood of domestic and wild animals was identified in triatomines collected in the intradomicile and in palms. These results support the extension of the wild cycle of T. cruzi to human dwellings and the characterization of a new scenario for transmission in Colombia.
Determining Barriers and Facilitators Associated With Willingness to Use a Personal Health Information Management System to Support Worksite Wellness Programs
Authors: Neyens David M. , Childers Ashley Kay
Published: January 2016

Purpose.

To determine the barriers and facilitators associated with willingness to use personal health information management (PHIM) systems to support an existing worksite wellness program (WWP).

Design.

The study design involved a Web-based survey.

Setting.

The study setting was a regional hospital.

Subjects.

Hospital employees comprised the study subjects.

Measures.

Willingness, barriers, and facilitators associated with PHIM were measured.

Analysis.

Bivariate logit models were used to model two binary dependent variables. One model predicted the likelihood of believing PHIM systems would positively affect overall health and willingness to use. Another predicted the likelihood of worrying about online security and not believing PHIM systems would benefit health goals.

Results.

Based on 333 responses, believing PHIM systems would positively affect health was highly associated with willingness to use PHIM systems (p < .01). Those comfortable online were 7.22 times more willing to use PHIM systems. Participants in exercise-based components of WWPs were 3.03 times more likely to be willing to use PHIM systems. Those who worried about online security were 5.03 times more likely to believe PHIM systems would not help obtain health goals.

Conclusions.

Comfort with personal health information online and exercise-based WWP experience was associated with willingness to use PHIM systems. However, nutrition-based WWPs did not have similar effects. Implementation barriers relate to technology anxiety and trust in security, as well as experience with specific WWP activities. Identifying differences between WWP components and addressing technology concerns before implementation of PHIM systems into WWPs may facilitate improved adoption and usage.
Light-Intensity Physical Activity and All-Cause Mortality
Authors: Loprinzi Paul D.
Published: January 2016

Purpose.

Research demonstrates that moderate-to-vigorous physical activity (MVPA) is associated with a reduced risk of all-cause mortality. Few studies have examined the effects of light-intensity physical activity on mortality. Therefore, the purpose of this study was to examine the association between objectively measured light-intensity physical activity and all-cause mortality risk.

Design.

Longitudinal.

Setting.

National Health and Nutrition Examination Survey 2003–2006 with follow-up through December 31, 2011.

Subjects.

Five thousand five hundred seventy-five U.S. adults.

Measures.

Participants wore an accelerometer for at least 4 days and completed questionnaires to assess sociodemographics and chronic disease information, with blood samples taken to assess biological markers. Follow-up mortality status was assessed via death certificate data from the National Death Index.

Analysis.

Cox proportional hazard model.

Results.

After adjusting for accelerometer-determined MVPA, age, gender, race-ethnicity, cotinine, weight status, poverty level, C-reactive protein, and comorbid illness, for every 60-minute increase in accelerometer-determined light-intensity physical activity, participants had a 16% reduced hazard of all-cause mortality (hazard ratio = .84; 95% confidence interval: .78–.91; p < .001).

Conclusion.

In this national sample of U.S. adults, light-intensity physical activity was inversely associated with all-cause mortality risk, independent of age, MVPA, and other potential confounders. In addition to MVPA, promotion of light-intensity physical activity is warranted.
A 2015 Survey of Forensic Economists: Their Methods, Estimates, and Perspectives
Authors: Luthy Michael R. , Brookshire Michael L. , Rosenbaum David , Schap David , Slesnick Frank L.
Published: January 2016

In January 2015, 590 e-mail invitations to complete an electronic survey were sent to NAFE (National Association of Forensic Economics) members. The response rate was approximately 33%, almost nine percentage points higher than the last paper survey administered in 2003. The survey covered many of the major topics included in earlier surveys, such as values of important economic variables (e.g., discount rates), trends in the practice of forensic economics (e.g., personal sources of earnings), and open-ended questions concerning ethics and reactions to the survey instrument. On the 2015 Survey instrument there were several new questions concerning such matters as how forensic economists perceive the role of vocational (rehabilitation) experts, the effects of the Affordable Care Act on loss estimates, how members charge for their services, and the size of respondents' practices.
A Comment on “Employee Tenure and Economic Losses in Wrongful Termination Cases”
Authors: Coleman Nicholas
Published: January 2016

In the April 2013 issue of the Journal of Forensic Economics, Charles L. Baum II develops a model to estimate the annual probability of a worker remaining with a particular employer and applies his results to estimates of economic losses resulting from wrongful termination. Baum's adjustment for job survival is based only on forecast experience in the job held at the time of the termination. This method seems inconsistent with Baum's own findings that early years in any job are associated with much higher hazard rates. In this comment we apply Baum's survival coefficients in a model that incorporates the probability of termination and survival in both the original job and the replacement job.
Employee Tenure and Economic Losses in Wrongful Termination Cases: A Reply to Nicholas Coleman
Authors: Baum Charles L.
Published: January 2016

In this issue of the Journal of Forensic Economics, Nicolas Coleman provides a critique of the model I developed (and presented in a recent issue of this journal) to predict the annual probabilities a worker would have stayed with a terminating employer absent the termination and its subsequent application. He then proposes an alternative approach, referred to as the Job-Specific Survival Method, when calculating economic losses in employment termination cases. In this note, I respond on Coleman’s critique.
ARTES VISUAIS E EAD: UM APRENDIZADO POSSÍVEL?
Authors: Lopes Andry Marcia , Vieira Fábia Magali Santos
Published: January 2016

Este trabalho tem como objetivo apresentar os dados de uma pesquisa desenvolvida durante o curso de especialização lato sensu em Didática e Metodologia do Ensino Superior na Universidade Estadual de Montes Claros (Unimontes). Esta pesquisa teve como objetivo compreender o processo de ensino-aprendizagem da disciplina Desenho em um curso de graduação em Artes Visuais a distância, identificando as dificuldades encontradas pelo docente e pelos discentes, bem como as estratégias didáticas utilizadas. As informações foram levantadas através de entrevistas e de pesquisa documental com portfólios de Desenho e análise das salas virtuais. Ao fim da pesquisa concluiu-se que é possível aprender o desenho em um curso a distância se houver na instituição uma estrutura que atenda às necessidades desta disciplina.
O HIBRIDISMO TECNOLÓGICO DIGITAL NA CONFIGURAÇÃO DO ESPAÇO DIGITAL VIRTUAL DE CONVIVÊNCIA: FORMAÇÃO DO EDUCADOR
Authors: Backes Luciana
Published: January 2016

O artigo aborda a formação do educador por meio das tecnologias digitais emergentes. A pesquisa contempla dois aspectos: contexto do hibridismo tecnológico digital; configuração dos espaços digitais virtuais de convivência. A reflexão ocorreu nos cursos de formação inicial do educador, desenvolvidos no Brasil e na França, no contexto do hibridismo tecnológico digital composto por: Ambiente Virtual de Aprendizagem; Comunicador Instantâneo; Blog e Metaverso. Por meio da metodologia de Estudo de Caso, evidenciamos que o espaço digital virtual de convivência se configura quando: os seres humanos representam a sua percepção em espaços digitais virtuais; a partir da representação de cada ser humano se instaura a perturbação, pois o outro é legítimo; há a necessidade de compensar a perturbação configurando um espaço comum, numa perspectiva de coexistência e de emergência.
CHIRONOMIDS OF THE YUCATÁN PENINSULA
Authors: Vinogradova Evgenia M. , Riss H. Wolfgang
Published: January 2016

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PALEOLIMNOLOGICAL EVIDENCE CONFIRMS THAT PAROCHLUS STEINENII (GERKE) IS
Authors: Agius Janelle T. , Gibson John A.E. , Rico Eugenio , Quesada Antonio
Published: January 2016

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Chironomidae and the tree of life
Authors: Ekrem Torbjørn
Published: January 2016

Editorial
CHIRONOMUS SAMOENSIS IS A COMPLEX OF SPECIES
Authors: Martin Jon
Published: January 2016

Chironomus samoensis, as currently recognised, is not a single species but a complex of more or less closely related species.  C. samoensis Edwards 1928 is redescribed from additional material, and considered to occur only in the Pacific region.  Reasons for excluding material from other areas are given.  C. flaviplumus Tokunaga 1940 is confirmed as the correct name for the Japanese material, the Indian material described by Chattopadhyay et al. (1991) is given the new name C. indiaensis, and new names are required for material from Australia and additional species from India.
Non-destructive DNA extraction from Chironomidae, including of fragile pupal exuviae, extends analysable collections and enhances vouchering
Authors: Krosch Matthew N , Cranston Peter S.
Published: January 2016

To be entered
Regeneration of old slide specimens mounted in Hoyer’s medium
Authors: Kobayashi Tadashi
Published: January 2016

An old, crystallized holotype mounted in Hoyer's medium was successfully regenerated with a method here described.
Chironomus Newsletter on Chironomidae Research
Authors: Ekrem Torbjørn , Langton Peter H , Anderson Alyssa M.
Published: January 2016

Whole issue
Differential efficiencies of dip-net sampling versus sampling surface-floating pupal exuviae in a biodiversity survey of Chironomidae
Authors: Ferrington Jr Leonard Charles , Coffman William P.
Published: January 2016

Relative efficiencies of standard dip-net sampling (SDN) versus collections of surface-floating pupal exuviae (SFPE) were determined for detecting Chironomidae at catchment and site scales and at subfamily/tribe-, genus- and species-levels based on simultaneous, equal-effort sampling on a monthly basis for one year during a biodiversity assessment of Bear Run Nature Reserve. Results showed SFPE was more efficient than SDN at catchment scales for detecting both genera and species. At site scales, SDN sampling was more efficient for assessment of a first-order site. No consistent pattern, except for better efficiency of SFPE to detect Orthocladiinae genera, was observed at genus-level for two second-order sites. However, SFPE was consistently more efficient at detecting species of Orthocladiinae, Chironomini and Tanytarsini at the second order sites. SFPE was more efficient at detecting both genera and species at two third-order sites. The differential efficiencies of the two methods are concluded to be related to stream order and size, substrate size, flow and water velocity, depth and habitat heterogeneity, and differential ability to discriminate species among pupal exuviae specimens versus larval specimens. Although both approaches are considered necessary for comprehensive biodiversity assessments of Chironomidae, our results suggest that there is an optimal, but different, allocation of sampling effort for detecting Chironomidae across stream orders and at differing spatial and taxonomic scales.Article submitted 13. August 2014, accepted 31. October 2014, published 22. December 2014.
A new Thalassosmittia Strenzke and Remmert, 1957 out of the sea: T. amazonica n. sp. from the Amazon rainforest, Brazil (Diptera: Chironomidae, Orthocladiinae)
Authors: Andersen Trond , Pinho Luiz Carlos
Published: January 2016

The orthoclad Thalassosmittia amazonica n. sp. is described based on a male collected in a light trap in the Amazon rainforest. The species is easily separated from its congeners as it has a strongly reduced palp with only a single palpomere.Article submitted 12. October 2014, accepted 10. November 2014, published 22. December 2014.
Lived Experiences of Iranian Nurses Caring for Brain Death Organ Donor Patients: Caring as “Halo of Ambiguity and Doubt”
Authors: Keshtkaran Zahra , Sharif Farkhondeh , Navab Elham , Gholamzadeh Sakineh
Published: January 2016

BACKGROUND: Brain death is a concept in which its criteria have been expressed as documentations in Harvard Committee of Brain Death. The various perceptions of caregiver nurses for brain death patients may have effect on the chance of converting potential donors into actual organ donors.

Objective: The present study has been conducted in order to perceive the experiences of nurses in care-giving to the brain death of organ donor patients.

METHODS: This qualitative study was carried out by means of Heidegger’s hermeneutic phenomenology. Eight nurses who have been working in ICU were interviewed. The semi-structured interviews were recorded bya tape-recorder and the given texts were transcribed and the analyses were done by Van-Mannen methodology and (thematic) analysis.

RESULTS: One of the foremost themes extracted from this study included ‘Halo of ambiguity and doubt’ that comprised of two sub-themes of ‘having unreasonable hope’ and ‘Conservative acceptance of brain death’. The unreasonable hope included lack of trust (uncertainty) in diagnosis and verification of brain death, passing through denial wall, and avoidance from explicit and direct disclosure of brain death in patients’ family. In this investigation, the nurses were involved in a type of ambiguity and doubt in care-giving to the potentially brain death of organ donor patients, which were also evident in their interaction with patients’ family and for this reason, they did not definitely announce the brain death and so far they hoped for treatment of the given patient. Such confusion and hesitance both caused annoyance of nurses and strengthening the denial of patients’ family to be exposed to death.

CONCLUSION: The results of this study reveal the fundamental perceived care-giving of brain death in organ donor patients and led to developing some strategies to improve care-giving and achievement in donation of the given organ and necessity for presentation of educational and supportive services for nurses might become more evident than ever.
Why Do Some First Nations Communities Have Safe Water and Others Not? Socioeconomic Determinants of Drinking Water Risk
Authors: Brown Brandon , Wachowiak-Smolíková Renata , Spence Nicholas D. , Wachowiak Mark P. , Walters Dan F.
Published: January 2016

Securing safe and adequate drinking water is an ongoing issue for many Canadian First Nations communities despite nearly 15 years of reports, studies, policy changes, financial commitments, and regulations. The federal drinking water evaluation scheme is narrowly scoped, ignoring community level social factors, which may play a role in access to safe water in First Nations. This research used the 2006 Aboriginal Affairs and Northern Development Canada First Nations Drinking Water System Risk Survey data and the Community Well-Being Index, including labour force, education, housing, and income, from the 2006 Census. Bivariate analysis was conducted using the Spearman’s correlation, Kendall’s tau correlation, and Pearson’s correlation. Multivariable analysis was conducted using an ordinal (proportional or cumulative odds) regression model. Results showed that the regression model was significant. Community socioeconomic indicators had no relationship with drinking water risk characterization in both the bivariate and multivariable models, with the sole exception of labour force, which had a significantly positive effect on drinking water risk rankings. Socioeconomic factors were not important in explaining access to safe drinking water in First Nations communities. Improvements in the quality of safe water data as well as an examination of other community processes are required to address this pressing policy issue.
Effect of defocusing on laser ablation plume observed by laser-induced fluorescence imaging spectroscopy
Authors: Oba Masaki , Miyabe Masabumi , Akaoka Katsuaki , Wakaida Ikuo
Published: January 2016

We used laser-induced fluorescence imaging with a varying beam focal point to observe ablation plumes from metal and oxide samples of gadolinium. The plumes expand vertically when the focal point is far from the sample surface. In contrast, the plume becomes hemispherical when the focal point is on the sample surface. In addition, the internal plume structure and the composition of the ablated atomic and ionic particles also vary significantly. The fluorescence intensity of a plume from a metal sample is greater than that from an oxide sample, which suggests that the number of monatomic species produced in each plume differs. For both the metal and oxide samples, the most intense fluorescence from atomic (ionic) species is observed with the beam focal point at 3–4 mm (2 mm) from the sample surface.