bluuebunny/crossref_metadata_2025 huggingface dataset:
Increase the Space Trajectory Precision by Using the Proper Assisted Research Method for Inverse Kinematics Problem
Authors: Olaru Adrian , Olaru Serban , Mihai Niculae
Published: September 2015

Inverse kinematics model of the industrial robot is used in the control of the end-effecter trajectory. The solution of the inverse kinematics problem is very difficult to find, when the degree of freedom increase and in many cases this is impossible. In these cases is used the numerical approximation or other method with diffuse logic. The paper showed one new method for optimization of the inverse cinematic solution by applying the proper assisted Iterative Pseudo Inverse Jacobian Matrix Method coupled with proper Sigmoid Bipolar Hyperbolic Tangent Neural Network with Time Delay and Recurrent Links Method (IPIJMM-SBHTNN-TDRLM). In the paper was shown one case study to obtain one space circle curve by using one arm type robot and the proposed method. The errors of the space coordinates of the circle, after applying the proposed method, was less than 0.001. The study has contained the determining the internal coordinates corresponding to the external coordinates of the circle space curve, by solving the inverse kinematics with the proposed method and after that, by applying the forward kinematics to this coordinates, were obtained the external coordinates, what were compared with the theoretical one. The presented method is general and it can be used in all other robots types and for all other conventional and unconventional space curves.
Modelling of the Human's Leg as a Switched Linear System
Authors: Babiarz Artur , Czornik Adam , Niezabitowski Michał , Zawiski Radosław
Published: September 2015

This article describes the alternative mathematical modelling of a human's leg by means of switched system approach. The leg is considered three joints connected by a rotational link. The novelty of each of the links being represented as a rectangular prism changing shape during motion introduces new possibilities of model application. Each of the links is represented as a rectangular prism which's shape depends on the three state coordinates - the angular displacements q1, q2 and q3. A design process is then made on the basis of switched system theory. In several steps we show the transition from the general equation of the three-link leg dynamics to the switched linear system where the switching rule depends on the state vector. A switching method is presented in schematics.
The Effects of Melt Compounding Method on the Ambient and In Vitro Mechanical Properties of EVA/MMT Nanocomposites
Authors: Osman Azlin Fazlina , Hong Tew Wei , Alakrach Abdulkader M.
Published: September 2015

The in vitro biostability of ethyl vinyl acetate (EVA) nanocomposite incorporating the organically modified montmorillonite (organo-MMT) was investgated as a new material for biomedical applications. The effects of compounding process and filler loadings on the ambient and in vitro (exposed in oxidizing condition, 37°C) mechanical properties were studied. We have observed that, the melt compounded EVA copolymer by internal mixer (Brabender plasticoder) achieved the highest ambient and in vitro mechanical properties at low nanofiller content (1wt% organo-MMT). In contrast, the melt compounded EVA copolymer by twin screw extruder achieved the highest ambient and in vitro mechanical properties at high nanofiller content (5wt% organo-MMT). We suggest that this was due to the capability of the twin screw extruder to provide greater shear force for the exfoliation and dispersion of the high content organo-MMT as compared to internal mixer (Brabender plasticoder). However, compounding by twin screw extruder caused more severe reduction in tensile toughness of the EVA containing 5 wt% organo-MMT, after this material was exposed to oxidative agent, 37°C. These studies show that the melt compounding method may bring significant effect to both the ambient and in vitro mechanical performance of the EVA nanocomposites, and hence further investigation towards optimization should be pursued.
Simulation-Based Analysis of a Linear Switched System Based on Human Arm’s Dynamics
Authors: Babiarz Artur , Klamka Jerzy , Niezabitowski Michał , Zawiski Radosław
Published: September 2015

The article outlines the process of developing a mathematical model of the human arm. The model arm consists of two joints connected by the rotational link. Each of them is represented as a truncated cone prism which changes its shape during motion. The shape change instant depends on the two-state coordinates being the angular displacements q1 and q2. Based on the analysis of the arm motion a mathematical model is proposed. The design process is made on the basis of switched systems theory. We present a transition from the general equation of a two-link arm’s dynamics to the state equation for stationary linear models. Based on previous step a mathematical model is presented as a switched linear system. The article also shows that the dependency of the switching rule on the two components of the state vector.
Cooling Performance Analysis of the Permanent Magnet Motor
Authors: Liu Wan , Zou Hai Rong , Tang Shou Jie , Wang Peng
Published: September 2015

This paper built 3D motor model by SolidWorks, using finite element software Fluent to simulate the temperature field and fluid field of the permanent magnet motor. The cooling effect of “C” type structure with different radiating rib was analyzed in this paper. Simulation analysis of motor temperature rise was carried out under different inlet flow. It provides a reference for the further study of motor shell optimization design.
Design on Electric Vehicle Battery Management System with FlexRay Bus
Authors: Peng Jian Kun , He Hong Wen , Pan Deng
Published: September 2015

FlexRay bus is considered as a more promising bus in the future with the performance of real-time, scalable, and fault-tolerant. In this paper we will design an electric vehicle battery management system (BMS) based on FlexRay bus, including the hardware design, the SoC estimation method, FlexRay protocol design and software development. The test bench experiment results show the system design is reasonable and feasible.Keywords- FlexRay, BMS, Li-ion battery,SoC, Design
A Unifying Model for Mechatronic Systems Specification
Authors: Al-Fedaghi Sabah , Abdullah Ahmed
Published: September 2015

Over the years, mechatronic systems have witnessed an increase in complexity. To address this issue, a model-based approach has been utilized to produce coherent system specification. In model-based engineering, a system is depicted graphically and textually at various levels of granularity and complexity. For this purpose, Systems Modeling Language (SysML) is designed to support development stages in systems, including specification, analysis, design, and validation, and to generate specifications in a single language for use by heterogeneous development teams. Nevertheless, an underlying tool is lacking that would express the totality of a system’s processes and concepts, including mechanical, electrical, and informational aspects. SysML introduces a variety of diagrams and tools that are heterogeneous in notation and terms, e.g., use cases, blocks, activities, components, parameters, sequence, and so forth. This paper proposes a diagrammatic methodology to specify a unified conceptual map for mechatronic systems that can play the role of blueprint for a whole system at different stages of development. The paper focuses on using the proposed methodology as a specification tool, offering a new model that captures the dynamic behaviors of the system. The claim is that this proposed model for specification provides a nontechnical map of the system without a multiplicity of representations as in SysML. To demonstrate the viability of the model, it is applied to a case study of an airport baggage handling system.
Data Cluster Detection for Low Power Embedded Memory Subsystems
Authors: Park Dae Jin , Cho Jeong Hun , Cho Doo San
Published: September 2015

This work proposes a technique for optimizing data placement of application-wide reused data so that it resides in scratchpad memory of processing elements in multiprocessor system on chips. The proposed technique identifies data elements with fine granularity that can profitably be placed in the scratchpad memories to maximize performance and energy gains. We present a heuristic approach that efficiently exploits the scratchpad memories using memory access footprint. Our experimental results indicate that our approach is able to reduce energy consumption by 30% over cache based memory subsystems.
Fractional Order Modeling and Analysis of Buck-Boost Converter
Authors: Yi Li Feng , Zhang Kai Ru , Liu Jun
Published: September 2015

Considered the theoretical foundation of fractional order, the fractional mathematical model of the Buck-Boost converter in continuous conduction mode operation is built and analyzed in theory. Based on the improved Oustaloup fractional calculus for filter algorithm, the simulation model is framed by using the Matlab/Simulink software. And the simulation results are compared with that of integer order. It proves the correctness of the fractional order mathematical model and the theoretical analysis.
The Turning Speed of Stability Control in Electric Learner-Driven Vehicle Driving
Authors: Chen Xi , Ma You Liang , Cheng Yan Zhi
Published: September 2015

This paper analyzes the differences between electric learner-driven vehicle and fuel cars in the process of turning, and establish a multiple parameter control model from the fuzzy control method, to determine driving resistance changes, and using PWM regulating motor armature voltage to control the rotate speed’s change, at the same time, we use the measured speed as feedback signal to regulate the armature voltage again. Realize the electric motor speed steady in the process of turning, make the electric learner-driven vehicle have the similar driving feeling with the fuel learner-driven vehicle.
Innovative Algorithm and Software for Three-Dimension Topography Evaluation in Laser-Micro Machining
Authors: Guo Li Bin , Yao Feng Long , Zhang Zhi Hang , Duan Yun Fei
Published: September 2015

Innovative algorithms and software evaluating the three-dimension topography in laser micro-machining are developed in this paper. First according to the features of the three-dimension surface consisted of micro peaks and pits, Gaussian curve parameters are presented and used to form a evaluation system with 22 parameters for three-dimension topography. Based on this, to completely and precisely evaluate the three-dimension topography,an assessment module for power spectral density is designed and implemented. Through integrating this module with the 22 parameters, a complete and precise evaluation system is built, which can evaluate the performance not only in vertical direction but also in horizontal is obtained. In software, through using MATLAB/GUI latest interface to implement integration, the following functions are implemented: surface three-dimension topography rebuilding, signal noise reducing, assessment data extracting, roughness calculating, and two-dimensional frequency domain analyzing. Furthermore, with this software, through comparing the parameters and spectrum, it is easy to determine the frequency affecting the roughness,thus providing some clues on how to further reduce the surface roughness. Test results show that this software system can provide more accurate assessment for the surfac three-dimension topography, and can be used to ultra-precision machining surface assessment.
Finite Element Analysis on Vibration of a Piezoelectric Micro Pump
Authors: Huang Bo Wun , Tseng Jung Ge , Chang Chien Hua
Published: September 2015

Due to the rise of biological and MEMS technology in recent years, some micro flow system components have been paid attentions to developed by many investigators. The importance of micro-pumps manufactured is higher than the other part of micro flow system since it is the power source of the entire micro-flow system and responsible for driving working fluid in the microfluidic system. In actual operation, the instability and bad dynamic characteristics of the micro-pump will cause larger fluid flow mobility error, such as transport behavior and response procedures failure, etc., and even damage the microfluidic system. Therefore, to investigate the stability and dynamic characteristics of a micro pump is necessary. The miniature piezoelectric film micro-pump, made by Microjet Technology Co., Ltd., is employed to study in this work. The computer graphics software SolidWorks is used to build the model of the micro pump. Then, The Finite element analysis (FEA), ANSYS Workbench, is also employed to analyze the dynamic characteristics of this micro pump.
Control Strategy and Deterministic Optimization Research for Parallel Compound Braking System
Authors: Lu Bing , He Hong Wen , Wang Qun Ce
Published: September 2015

Through the design way of reducing dimension, a control algorithm of the parallel compound braking is put forwarded. The flow of reducing dimension is designed, the sampling which is based on the Design of Experiment (DOE) and off-line deterministic optimization are accomplished. The reducing dimension of dual-motor coordinate coefficient is designed and the prediction model of parallel compound braking is constructed, which are based on the data of deterministic optimization. The analysis of reliability shows that the algorithm has a higher reliability and the energy recovery efficiency of the vehicle regenerative braking is improved under the condition of well braking stability.
Predictive Functional Control for a Pneumatic Cylinder
Authors: Hashimoto Yusuke , Satoh Toshiyuki , Nagase Jun Ya , Saga Norihiko
Published: September 2015

Japan is becoming a super-aging society, with a population decrease and a shortage of young workers. Mechanisms using pneumatic cylinders are therefore expected to be useful to perform tasks such as day-to-day work support for elderly people. However, pneumatic cylinder includes large dead time. Thereby, traditional control system is complex, such as adding Smith compensation. Therefore, we use Predictive Functional Control (PFC). This control system is not complex even if plant includes dead time. This study evaluates the performance of force and position control systems using a pneumatic cylinder and PFC. We compare the PFC scheme with the PID control and show that PFC achieves better performance than PID control.
Development and Implementation of an Automated Car Parking System
Authors: Mohammed Thabit Sultan , Al-Khairi Waleed K. , Al-Jubouri Aamer T. , Shamas Omar S.
Published: September 2015

The problems related to shortages in car parking spaces in dense populated cities and areas is addressed, and the categories of automated advanced car parking systems based on their different technologies is presented. The concept of an automatic car parking system is also introduced and demonstrated through the development process of a prototype using a PIC microcontroller. Simulation for the system's circuits is done with the aid of Proteus software. The hardware circuits, which are built on printed circuit boards (PCB) are interfaced with actuators and sensors for automation purposes. The hardware is assembled to automatically open entry gates for cars while there are still some unoccupied parking spaces. The entry gate will not be opened, however as long as the car parking facility is full. Proper messages are displayed on a screen to reflect the status of the car parking facility.
Estimation of Unknown Disturbances in Gimbal Systems
Authors: Kürkçü Burak , Kasnakoğlu Coşku
Published: September 2015

This paper presents a method for the estimation of unknown disturbances for high precision gimbal systems. Alternative to the classical methods of model inversion and filtering, we employ an asymptotically stabilizing controller which achieves the estimation process even in the presence of unstable zeros. The architecture provides an input equivalent disturbance which can be thought to capture all real disturbances in the system as well as virtual ones such as unmodelled dynamics and nonlinearities. The proposed method is illustrated on a 2-axis gimbal system where system identification is followed by the design on an integral linear quadratic regulator as the stabilizing controller which forms the base of the disturbance observer. It is seen that a random unknown disturbance is estimated successfully in the presence of additional gyro noise.
Tire Force Control Strategy for Semi Active Magnetorheological Damper Suspension System Using Quarter Heavy Vehicle Model
Authors: Sulaiman Syabillah , Samin Pakharuddin Mohd , Jamaluddin Hishamuddin , Rahman Roslan Abd , Abu Bakar Saiful Anuar
Published: September 2015

This paper proposed semi active controller scheme for magnetorheological (MR) damper of a heavy vehicle suspension known as Tire Force Control (TFC). A reported algorithm in the literature to reduce tire force is Groundhook (GRD). Thus, the objective of this paper is to investigate the effectiveness of the proposed TFC algorithm compared to GRD. These algorithms are applied to a quarter heavy vehicle models, where the objective of the proposed controller is to reduce unsprung force (tire force). The simulation model was developed and simulated using MATLAB Simulink software. The use of semi active MR damper using TFC is analytically studied. Ride test was conducted at three different speeds and three bump heights, and the simulation results of TFC and GRD are compared and analysed. The results showed that the proposed controller is able to reduced tire force significantly compared to GRD control strategy.
Independent Control of Force & Displacement Using Shape Memory Alloy Tactile Display
Authors: Alalem Hussein Mohammed
Published: September 2015

This paper proposes one of the possible techniques for interacting for shape memory alloy (SMA) actuator based tactile display, which can act as demonstrator devices. This work is focused on developing a model of a pair of antagonistic high strain SMA tension actuators with independent control of force and displacement. The technology employed utilizes two Flexinol 100 micron heat actuated wires of Titanium-Nickel (NiTi) shape-memory alloy which contract when heated under pre-stress and produces up to 5% strain recovery. This phenomenon, which provides a unique mechanism for actuation, is associated with the unique interaction between the martensite and austenite crystal structures of the SMA. Physical measurements of the behaviour of the actuator elements were performed using a laser displacement sensor to verify the fidelity of response to software commands, and to measure step response to pulse-width modulated (PWM) current control at different frequencies and duty cycles. Results yielded high accuracy across a wide range of frequencies and duty cycles, proving the SMA actuation technique has potential to present and convey useful tactile information of surface deformation for virtual environment applications.
A Grating Monopole Antenna on Metamaterial Using MSRR for DVB-T Application
Authors: Zebiri C. , Lashab Mohamed , Benabdelaziz Fatiha , Abd-Alhameed R.A. , Elmegri Fauzi
Published: September 2015

This work presents a novel broadband monopole antenna for digital video broadcasting-terrestrial (DVB-T) application. The proposed antenna consists of a grating patch and a concave rectangular ground plane with defected ground plane, and the Multiple Split-Ring Resonator (MSRR). The added part in the ground plane and the meta-material are used to enable the antenna height reduction for fixed ranges of operating frequency. The antenna can operate from 468 MHz to 894 MHz frequency range corresponding to 62.5% of impedance bandwidth for |S11|<-7.5 dB. Details of the proposed antenna designs and experimental results of the constructed prototypes are presented and discussed.
Preparation and Properties Investigation of Polyetherimide/Bamboo Charcoal Composites with High Dielectric Constant
Authors: Wu Chia Ching , Diao Chien Chen , Yang Cheng Fu , Huang Ying Pin , Tzou Gow Yi
Published: September 2015

The physic and dielectric properties of the polyetherimide/bamboo charcoal (PEI/BC) composites were studied by using bamboo charcoal as the conductive filler. The PEI/BC composites are fabricated using PEI, dispersant, solvents, and BC powder (BCP). The effects of the content of BCP on the physical and dielectric properties of PEI/BCP composites are studied in this research. Two different electric conductivity of BCP (BCP1 and BCP2) were used as the filler mixing with the polyetherimide, and the electric conductivity of BCP1 is higher than the BCP2. As the content of BCP1 and BCP2 increases from 10 to 70 wt%, the dielectric constants of PEI/BC1 and PEI/BC2 composites at 1 MHz increases from 5.06 to 19.73 and 4.7 to 18.9, respectively. All loss tangents of PEI/BC1 and PEI/BC2 composites are less than 0.04 at measured frequencies from 1 kHz to 1 MHz.
Constant Pressure Control for Energy Efficient Lathe Turret
Authors: Renn Jyh Chyang , Hsu Wen Jen , Li Yun Ruei
Published: September 2015

Hydraulic system plays an important role in many power systems such as excavator, braking system of vehicle and machine tool. Generally speaking, hydraulic control system can be divided into two different driving concepts. The first one is the well-known valve-controlled system and the second one is the pump-controlled system. The former possesses the feature of fast dynamic response. However, the poor energy-saving performance is its major fault. On the contrary, the pump-controlled system has the significant advantage of energy-saving which meets the current demand in modern machine design, but has the disadvantage of slower dynamic response. With the advancement of electric-motor system, however, this disadvantage has been greatly improved. In this paper, the simulation analysis of a newly developed energy-efficient hydraulic CNC lathe turret based on constant pressure control scheme is presented. Instead of the conventional fixed displacement hydraulic pump, the new energy-efficient system utilizes an internal gear pump together with an AC servo motor as its driving power source. In addition, a closed-loop control scheme using PID control is adopted. From simulation results, the new energy-efficient design can reduce the waste of the output flow-rate of the pump through the relief valve that generally happens in conventional hydraulic lathe and then achieve the purpose of designing an energy-efficient hydraulic lathe.
Interference of Die Equipment for Hexagonal Flange Nut Forming Process
Authors: Chou Yu Tuan , Hsia Shao Yi , Shih Po Yueh
Published: September 2015

Most cold forging die insert materials are powder sintered tungsten steel materials, which can hardly bear the circumferential tension and stress that the die insert longitudinal fracture is easily caused. For this reason, this study intends to investigate effects of die insert pre-stress resulted from shrink fit interference on the die to prevent the product accuracy and service life from being reduced due to the die failure in the forging process. The die effective stress distribution is also calculated in this study, and the interference is added between tungsten steel die inserts and cases to prevent tungsten steel from being damaged by the circumferential stress. The die stress distribution caused by common shrink fit interference in the industry is also investigated. The optimal interference acquired under the design criteria of decreasing equivalent stress presents 0.4%, 0.2%, 0.1%, 0.8%, and 0.1% at different stages. The research results could be the reference to select the optimal parameter for the die design and further shorten the product development effectiveness and reduce the costs.
The Effects of Grain Size and Lubrication on Micro Curl Forming Process of Metallic Thin Sheet
Authors: Chen Chang Cheng , Ho Huey Lin
Published: September 2015

This article aims at the discussion of deformation behavior considering size effect on curl forming process of sheet metal. In this study, the test specimens were made by phosphor bronze sheets for curl forming test. The specimens with different thickness were firstly heated at different temperatures for obtaining the objective grain sizes. And the mechanical properties of specimen were acquired by using tensile test. Through the curl forming test with a curl forming machine, the curled angles, springback and curling load were measured and analyzed for investigating the grain size effect of the chamfer and carbon lubricant during the curl forming process.
Influence of blanching on antioxidant, nutritional and physical properties of bamboo shoot
Authors: Badwaik L. S. , Gautam G. , Deka S. C.
Published: September 2015

Quality of bamboo shoots gets deteriorate rapidly during storage and transportation due to enzymatic browning and microbial attack. Therefore, effect of blanching temperature (75, 85 and 95°C) and time (5, 10, 15, 20, 25 and 30 min) on different physic-chemical properties of bamboo shoot cubes were assessed. Blanching time and temperature have significantly influenced the nutrients like protein, carbohydrate and reducing sugar contents. The highest changed in values of protein, carbohydrate and reducing sugar were reported from 3.42 to 2.24, 4.08 to 2.25, 1.33 to 0.87 g/ 100 g, respectively. The influence was less on ash and crude fiber. Retention of ascorbic acid, total phenolics and antioxidants were higher in 75°C and/or short time blanching (5- 10 min) which were gradually reduced at 85 and 95°C and/or long time blanching (20-30 min). The higher blanching temperature decreases in lightness value and long time blanching deteriorate the texture of bamboo shoot. Low temperature short time blanching was shown to result in better product quality with respect to physical properties besides nutrient retention.The Journal of Agricultural Sciences, vol.10, No 3, September 2015, pp.140-150
Genetic variability and interrelationships among quantitative traits in rapeseed (Brassica napus l.) advanced lines
Authors: Rameeh V.
Published: September 2015

Improvement of the new rapeseed (Brassica napus L.) cultivars requires efficient tools to monitor traits relationship in a breeding program. Thirty six rapeseed genotypes were evaluated based on randomized complete block design with three replications at Baykola Agricultural Research Station during 2010-11 and 2011-12 growing seasons. Significant genotypes effects were exhibited for phenological traits, plant height, yield components, seed and oil yields, indicating significant genetic differences among the genotypes. Broad sense heritability values were greater for days to flowering (0.98), pods per plant (0.71) and seeds per pod (0.77), indicating that these traits are controlled mainly by genetic effects and therefore selection of these traits may be effective for improving seed yield. Pods per plant and seeds per pod were significant positive correlated with seed yield and the results of stepwise regression analysis indicated that these traits explained 73% of total yield variation. On the basis of cluster analysis, all the genotypes were classified in three groups, and the group with high mean values of plant height, pods per plant and seeds per pod had also high mean values of seed and oil yields. The Journal of Agricultural Sciences, vol.10, No 3, September 2015, pp.158-167
Assessment of Transfer of Cocoyam Technologies in Anambra State, Nigeria
Authors: Olatunji S. O. , Nwakor F. N. , Asumugha G. N.
Published: September 2015

Agricultural transformation can be achieved in Nigeria in the presence of an effective, well-designed and well executed system of technology development and transfer. Multistage random sampling procedure was employed to select a sample of 36 EAs from the population of all Extension Agents (EAs) in Anambra State Agricultural Development Project (ADP). Research data were collected with the aid of structured questionnaire while data were analyzed using descriptive statistics (mean, percentage, ranks) and inferential statistics (multiple regression analysis). The results of data analyses revealed low percentage of young Extension Agents and low percentage of female EAs. A few academically unqualified EAs were on the roll of Anambra State ADP. The transfer of cocoyam technologies in the State has exceeded 73% of its target even as 17 out of 23 cocoyam technologies under study have been transferred to farmers. The major constraints to cocoyam technologies transfer relates to poor conditions of service for EAs, lack field vehicles, poor funding of extension activities, rejection of technologies by farmers on the basis of incompatibility of technologies to farmers’ local practices, inadequate number EAs and poor linkage among Research/Extension/ Farmer/Input Agencies. It was recommended that vigorous efforts be put in place to transfer 6 other cocoyam technologies which were yet to be transferred to the farmers. Also, more young and female EAs should be recruited. The conditions of service of EAs should be improved and that the ideal Training and Visit system of agricultural extension be implemented while research adapt cocoyam technologies to farmers’ local conditions and practices. The Journal of Agricultural Sciences, vol.10, No 3, September 2015, pp.168-176
Courtship sequence and evidence of volatile pheromones inPhasgonophora sulcata(Hymenoptera: Chalcididae), a North American parasitoid of the invasiveAgrilus planipennis(Coleoptera: Buprestidae)
Authors: Roscoe Lucas E. , Lyons D. Barry , Ryall Krista L. , Smith Sandy M.
Published: September 2015

Phasgonophora sulcataWestwood (Hymenoptera: Chalcididae) is a North American parasitoid now usingAgrilus planipennisFairmaire (Coleoptera: Buprestidae) as a novel host, and may prove useful in biocontrol. Unfortunately, information is lacking regarding mating and the presence of pheromones, which may be important when attempting to exploit this parasitoid within a management context. Herein we used olfactometer assays and behavioural observations to determine the courtship and mating sequences ofP. sulcata.A significantly higher proportion of males oriented towards females over the control arm containing filtered air in an olfactometer regardless of the age classes of females or males examined. We also observed four pre-copulatory behaviours that were consistent in all mating pairs. Our results indicate that courtship may be mediated by male perception of female-produced pheromones. Understanding the courtship sequence may be useful in rearing laboratory populations, while the putative pheromones may be useful in detection and retention ofP. sulcatapopulations.
Targeting Breast Cancer Metastasis
Authors: Jin Xin , Mu Ping
Published: September 2015

Metastasis is the leading cause of breast cancer-associated deaths. Despite the significant improvement in current therapies in extending patient life, 30–40% of patients may eventually suffer from distant relapse and succumb to the disease. Consequently, a deeper understanding of the metastasis biology is key to developing better treatment strategies and achieving long-lasting therapeutic efficacies against breast cancer. This review covers recent breakthroughs in the discovery of various metastatic traits that contribute to the metastasis cascade of breast cancer, which may provide novel avenues for therapeutic targeting.
Engaging Medical Students in the Basic Science Years with Clinical Teaching
Authors: Burgess Annette , Mellis Craig
Published: September 2015

Education of future medical practitioners involves the stewarding of knowledge and skills, and the development of values required for responsible practice. Students must not only master a vast amount of knowledge and theory but also understand how to apply it. A key challenge for medical educators is to approach this in a balanced and integrated manner, particularly within the basic science years of the medical program. The purpose of this article is to consider how the clinical environment, teaching methods, assessment, and feedback impact on the engagement of junior medical students.
Transition Networks in a Cohort of Patients with Congestive Heart Failure
Authors: Sheehan B. M. , Carley K. M. , Stetson P. D. , Merrill J. A.
Published: September 2015

Background: Unnecessary hospital readmissions are one source of escalating costs that may be reduced through improved care coordination, but how best to design and evaluate coordination programs is poorly understood. Measuring patient flow between service visits could support decisions for coordinating care, particularly for conditions such as congestive heart failure (CHF) which have high morbidity, costs, and hospital readmission rates.

Objective: To determine the feasibility of using network analysis to explore patterns of service delivery for patients with CHF in the context of readmissions.

Methods: A retrospective cohort study used de-identified records for patients 18 years with an ICD-9 diagnosis code 428.0–428.9, and service visits between July 2011 and June 2012. Patients were stratified by admission outcome. Traditional and novel network analysis techniques were applied to characterize care patterns.

Results: Patients transitioned between services in different order and frequency depending on admission status. Patient-to-service CoUsage networks were diffuse suggesting unstructured flow of patients with no obvious coordination hubs. In service-to-service Transition networks a specialty heart failure service was on the care path to the most other services for never admitted patients, evidence of how specialist care may prevent hospital admissions for some patients. For patients admitted once, transitions expanded for a clinic-based internal medicine service which clinical experts identified as a Patient Centered Medical Home implemented in the first month for which we obtained data.

Conclusions: We detected valid patterns consistent with a targeted care initiative, which experts could understand and explain, suggesting the method has utility for understanding coordination. The analysis revealed strong but complex patterns that could not be demonstrated using traditional linear methods alone. Network analysis supports measurement of real world health care service delivery, shows how transitions vary between services based on outcome, and with further development has potential to inform coordination strategies.

Citation: Merrill JA, Sheehan BM, Carley KM, Stetson PD. Transition networks in a cohort of patients with congestive heart failure: a novel application of informatics methods to inform care coordination. Appl Clin Inform 2015; 6: 548–564

http://dx.doi.org/10.4338/ACI-2015-02-RA-0021
Modelaje del cambio de uso del suelo y la deforestación futura en dos escalas espaciales
Authors: Cruz-Huerta Carmina , González-Guillén Manuel J. , Martínez-Trinidad Tomás , Escalona-Maurice Miguel J.
Published: September 2015

En este estudio se determinó el cambio de uso de suelo en la región de Chignahuapan-Zacatlán, Puebla, mediante un análisis bitemporal entre 1986 y 2011; la evaluación se hizo también para cada municipio. El cambio de uso de suelo se detectó mediante el manejo de imágenes Landsat. Los usos predominantes a nivel regional son el agrícola (49.7 %) y el forestal (46.1 %). En el caso de Chignahuapan, el uso agrícola representa la actividad principal con 58.9 % del territorio, mientras que en Zacatlán predomina el uso forestal con 57.3 %. A nivel regional y para el municipio de Zacatlán, el cambio de uso del suelo forestal se correlacionó significativamente (P ≤ 0.05) con 21 variables independientes, mediante un modelo probabilístico; en el caso de Chignahuapan, el modelo consideró 16 variables. A nivel regional, la probabilidad de cambio de uso de suelo forestal varió de 5 a 90 % y a nivel municipal de 7 a 99.8 %. Finalmente, la proyección para el año 2030 estima que el riesgo de deforestación a nivel regional y en los municipios de Chignahuapan y Zacatlán será de 13,063.8, 10,966.6 y 4,405.5 ha, respectivamente.
Efecto del gradiente altitudinal sobre la variación morfométrica y la simetría foliar de Platanus mexicana Moric
Authors: Galván-Hernández Dulce Ma. , Lozada-García J. Armando , Flores-Estévez Norma , Galindo-González Jorge , Vázquez-Torres S. Mario
Published: September 2015

La variación morfométrica y simetría foliar de una población de Platanus mexicana se caracterizaron en un gradiente altitudinal ripario del estado de Veracruz. Ocho caracteres morfométricos se evaluaron en 1,800 hojas provenientes de 15 individuos por sitio (70, 200, 600 y 1,700 m de altitud). Las diferencias morfométricas entre sitios (F(24, 5189) = 21.1, P < 0.05) se determinaron con un análisis de funciones discriminantes. Los caracteres relacionados con el largo y ancho de las hojas determinaron diferencias significativas (P ≤ 0.05) a nivel intrapoblacional. Con base en las distancias de Mahalanobis, el sitio ubicado a 70 m de altitud es el más distante morfométricamente. El análisis de conglomerados mostró 10 grupos foliares diferentes entre sí a lo largo del gradiente altitudinal. Existen diferencias en el tamaño foliar de mayor a menor altitud, indicando que hay hojas más grandes a 70 m. El índice de simetría foliar de P. mexicana no mostró diferencias significativas (P > 0.05) entre sitios del gradiente altitudinal del río Colipa. Los resultados fueron útiles para determinar la capacidad de respuesta de P. mexicana ante la heterogeneidad ambiental a lo largo del gradiente altitudinal del río Colipa.
Modelado de cambios de cobertura y uso del suelo: escenarios prospectivos en el Estado de México. Estudio de caso Amanalco de Becerra
Authors: Camacho-Sanabria José M. , Juan-Pérez José I. , Pineda-Jaimes Noel B.
Published: September 2015

El presente estudio tiene como propósito evaluar la dinámica y los procesos de transformación ocurridos en el municipio de Amanalco de Becerra, Estado de México, mediante la construcción de un modelo espacialmente explicativo de cambios de cobertura y uso del suelo (CCUS). El proceso de modelado se realizó con la herramienta DINAMICA EGO, utilizando como insumos cartográficos los mapas de uso de suelo y vegetación de los años 1989, 1997 y 2009, y algunas variables explicativas de proximidad, físico-geográficas, ambientales y de explotación de la tierra. Los CCUS se modelaron para el año 2020 bajo dos escenarios: tendencial y agropastoril. El escenario tendencial supone que las tasas anuales de cambio del periodo 1997-2009 se mantienen, mientras que el agropastoril presume que las tasas anuales de deforestación aumentan a causa de la apertura, establecimiento y desarrollo de actividades agropecuarias. El análisis de los valores absolutos de la categoría bosque, para cada año, muestra tendencia hacia la pérdida de la cobertura forestal; por lo contrario, las tasas anuales de cambio de esta misma cobertura tienden hacia procesos relacionados con la recuperación-revegetación-reforestación, producto de la implementación de programas ambientales gubernamentales.
Atmospheric chemistry of nitrogenous aerosols in northeastern Asia: biological sources and secondary formation
Authors: Pavuluri C. M. , Kawamura K. , Fu P. Q.
Published: September 2015

Abstract. To better understand the sources of nitrogenous aerosols, particularly water-soluble organic nitrogen (WSON) and water-insoluble organic nitrogen (WION), in northeastern Asia, we measured total nitrogen (TN) and water-soluble total nitrogen (WSTN) as well as nitrogen isotope ratios (δ15N) of TN (δ15NTN) and WSTN (δ15NWSTN) in the total suspended particulate (TSP) samples collected from Sapporo, northern Japan, for a 1-year period. In general, WION was more abundant (126 ± 117 ng m−3), whereas WSON was 89.7 ± 80.6 ng m−3, accounting for 14 ± 11 % and 9.2 ± 7.3 % of TN, respectively. WSON peaked in late autumn to winter (maximum 288 ng m−3) and WION peaked in mid-spring to early summer (454 ng m−3). δ15NTN (21.9 ± 4.1 ‰) and δ15NWSTN (25.8 ± 8.2 ‰) showed peaks in summer with relatively high ratios in late autumn. Based on the seasonal variations in WSON and WION together with organic tracers, fossil fuel combustion and biomass burning are found to be two major sources of WSON, whereas emissions of biological particles and secondary formation by reactions of biogenic secondary organic species (carbonyls) with NH3 are suggested as an important source of WION. The seasonality of δ15NTN and δ15NWSTN, together with the comparisons to literature values, implies that chemical aging (including gas–particle partitioning) and biomass burning are the causes of the enhanced values in summer and autumn, respectively. This study demonstrates that contributions of aerosol N from fossil fuel combustion and biomass burning dominate in autumn and/or winter, whereas emission of terrestrial biological particles and secondary formation from biogenic hydrocarbons and subsequent chemical aging in the atmosphere are important in spring and/or summer in northeastern Asia.
A new method for estimating emission ratios in the urban atmosphere: examples of ratios to CO2, CO and volatile organic compounds in Paris
Authors: Ammoura L. , Xueref-Remy I. , Vogel F. , Gros V. , Baudic A. , Bonsang B. , Delmotte M. , Té Y. , Chevallier F.
Published: September 2015

Abstract. We propose a new approach to estimate urban emission ratios that takes advantage of the enhanced local urban signal in the atmosphere at low wind speed. We apply it to estimate monthly ratios between CO2, CO and some VOCs from several atmospheric concentration measurement datasets acquired in the centre of Paris between 2010 and 2014. We find that this approach is little sensitive to the regional background level definition and that, in the case of Paris, it samples all days (weekdays and weekends) and all hours of the day evenly. A large seasonal variability of the ΔCO/ΔCO2 ratio in Paris is shown, with a difference of around 60 % between the extreme values and a strong anti-correlation (r2 = 0.75) with atmospheric temperature. The comparison of the ratios obtained for two short measurement campaigns conducted in two different districts and two different periods (fall and winter) shows differences ranging from −120 to +63 %. A comparison with a highly resolved regional emission inventory suggests some spatial variations of the ratio within the city, although most of these differences seem to be rather driven by the seasonal variability.
Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides
Authors: Degrendele C. , Okonski K. , Melymuk L. , Landlová L. , Kukučka P. , Audy O. , Kohoutek J. , Čupr P. , Klánová J.
Published: September 2015

Abstract. This study presents a comparison of seasonal variation, gas-particle partitioning and particle-phase size distribution of organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in air. Two years (2012/2013) of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. The timing and frequencies of detection of CUPs related to their legal status, usage amounts and their environmental persistence, while OCPs were consistently detected throughout the year. Two different seasonal trends were noted: certain compounds had higher concentrations only during the growing season (April–September) and other compounds showed two peaks, first in the growing season and second in plowing season (October–November). In general, gas-particle partitioning of pesticides was governed by physicochemical properties, with higher vapor pressure leading to higher gas phase fractions, and associated seasonality in gas-particle partitioning was observed in nine pesticides. However, some anomalous partitioning was observed for fenpropimorph and chlorpyrifos suggesting the influence of current pesticide application on gas-particle distributions. Nine pesticides had highest particle phase concentrations on fine particles (< 0.95 μm) and four pesticides on coarser (> 1.5 μm) particles.
On the characteristics of aerosol indirect effect based on dynamic regimes in global climate models
Authors: Zhang S. , Wang M. , Ghan S. J. , Ding A. , Wang H. , Zhang K. , Neubauer D. , Lohmann U. , Ferrachat S. , Takeamura T. , Gettelman A. , Morrison H. , Lee Y. H. , Shindell D. T. , Partridge D. G. , Stier P. , Kipling Z. , Fu C.
Published: September 2015

Abstract. Aerosol-cloud interactions continue to constitute a major source of uncertainty for the estimate of climate radiative forcing. The variation of aerosol indirect effects (AIE) in climate models is investigated across different dynamical regimes, determined by monthly mean 500 hPa vertical pressure velocity (ω500), lower-tropospheric stability (LTS) and large-scale surface precipitation rate derived from several global climate models (GCMs), with a focus on liquid water path (LWP) response to cloud condensation nuclei (CCN) concentrations. The LWP sensitivity to aerosol perturbation within dynamic regimes is found to exhibit a large spread among these GCMs. It is in regimes of strong large-scale ascend (ω500 < −25 hPa d−1) and low clouds (stratocumulus and trade wind cumulus) where the models differ most. Shortwave aerosol indirect forcing is also found to differ significantly among different regimes. Shortwave aerosol indirect forcing in ascending regimes is as large as that in stratocumulus regimes, which indicates that regimes with strong large-scale ascend are as important as stratocumulus regimes in studying AIE. It is further shown that shortwave aerosol indirect forcing over regions with high monthly large-scale surface precipitation rate (> 0.1 mm d−1) contributes the most to the total aerosol indirect forcing (from 64 to nearly 100 %). Results show that the uncertainty in AIE is even larger within specific dynamical regimes than that globally, pointing to the need to reduce the uncertainty in AIE in different dynamical regimes.