bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Ag Wire and Cu Wire in Memory Package
Authors: Liqun Gu , Qiang Chen , Juanjuan Li , Zhengrong Chen , Jianwei Zhou , Maohua Du , Chung Myungkee
Published: March 2013

Recently, there is growing interest in other bonding wire material alternative to Au, because the cost of Au has dramatically increased. In these studies, Cu wire is the most popular candidate due to its cost savings, better electrical and mechanical properties. But the high hardness of Copper is the ineluctable and fatal problem in it, which will limit the ball bonding process and the applications of Cu wire. Therefore, as another alternative choice to Au wire, Ag wire is investigated.Ag wire and Cu wire were evaluated on the Aluminum pad of memory device. The interface was characterized and the bondability was compared. Pad crack has been observed in Cu wire, which induced leakage fail in electrical test. Contrastively, in case of Ag wire, good interface and bondablity could be got. Reliability behaviors were also examined, especially uHAST (85%RH, 130’C) and HTS (150’C) test. After reliability test, the interfaces were characterized by FIB, TEM and EDS. The characterization of IMC was verified. The founds show that degradation of reliability is caused by IMC corrosion and the corrosion can be suppressed significantly by increased Pd content .The improved Ag wire can pass uHAST 480h and HTS 1000h. From this study, Ag bonding wire, as the low cost wire, is proposed as an alternative to Cu wire on fragile Aluminum pad in memory device.
Yellowing Mechanism and Solution for Chip Card Module
Authors: Jun Chen , QuanRong Zhu , XiaoJun Yang , Minqiang Miao , Haimerl Alfred , Song Cui , Weimin Chen
Published: March 2013

Mold process needs a degating and post curing steps which result in yellowing dots of products on ISO side. Analysis of FTIR, TGA, DSC, SEM, EDX were done on the yellowing dots and root cause was found. Nitrogen protection was introduced to prevent yellowing dots and nitrogen flow should be larger than 2000 liter/h to ensure enough concentration of nitrogen, result is positive and yellowing dots issue were not happened for the following production.
Advanced Test Solution for Data Dependent Jitter Characterization of Hsio on ATE
Authors: Lu Ming , Jose Moreira
Published: March 2013

Jitter is the core testing spec in HSIO device characterization phase. Normally peak-to-peak jitter is measured with spec search method on ATE. But it is not sufficient due to some advanced processors require to get the knowledge of sources of deterministic jitter, especially the Data dependent jitter. In this paper, an approach for measuring the DDJ on Advantest 93K test platform is introduced, and the correlation data with bench instrumentation is shown.
Demodulation Test for WCDMA RF-SOC in ATE
Authors: Xian Li
Published: March 2013

Today more and more chips include most complex combining RF/IF functions with digital, analog and DSP functions, which are called System-on-chip (SOC). Usually, these consuming SOCs are electrically test with Automatic Test Equipment (ATE). In test strategies, error vector magnitude (EVM) is often used to evaluate the actual ability of SOC device to perform properly in the system. In this paper, brief introduction to EVM test is given, and test methodologies in ATE system V93000 is introduces. A new test method for EVM using equalization function to optimize RF source signal is proposed to compensate interference in test system. Using this method, device performance is better characterized and also improves the yield in production test.
Application of Self-Diagnosis on Automation Bench Test Platform
Authors: Yang Xian , Qin Weijun
Published: March 2013

This article is to introduce a novel concept in IC bench test with automation. A test platform was setup to perform the FPGA test. All the tests were automated controlled using python code with GPIB protocol. Self-diagnosis and adjusting method was introduced in the test. A Lattice FPGA device was used in the experiment. The result shows 94.9% failure can be identified using this platform. The fast bug identification and test adjust has been achieved. Meanwhile the self-adjust makes the 99.5% test pass rate without manually tuning which has reduced the retest time significantly.
OCD Measurement with the Illuminated Light Spot Size Being Larger than the Grating Region
Authors: Zhang ZhenSheng , Wang Xin , Dang JiangTao , Li HaiTao , Shi Yaoming , Yang Feng , Xu Yiping
Published: March 2013

This work studied the case that the illumination light spot size is larger than the grating region during optical critical dimension (OCD) measurement. The analysis is based on Mueller matrix formulism. The total Mueller matrix output is the combination of both the grating Mueller matrix contribution and the surrounding film Mueller matrix contribution. The spectroscopic reflectometry (SR) and spectroscopic ellipsometry (SE) outputs are calculated from total Mueller matrix elements. The measurements with different ratios of illuminated grating area to illuminated film area are carried out. The measured spectra coincide well with the simulated ones. The work will be useful for IC industry, as the measurement pad size becomes even smaller.
New Design of SPC Control Limit Setting Flow for Super Large Amount of Engineering Data
Authors: Kang Sheng Randy , Ma Jinyi Jenny , Ji Xinyuan Serena
Published: March 2013

SPC (Statistic Process Control) Control charts are widely used to establish and maintain statistical process control in many domains for process performance shift detection. But the assumption of process data distribution is a potential risk to cause unexpected alarm ratio when we use inadequate control limit setting method. In manufactory practice, we found many engineering data are not following normal distribution. So one by one to analyzes and data transmit is hard to execute in practice, special for large amount of engineering data in semiconductor manufactory. Therefore, in this paper we propose to use different control methods or control chart for the different data types. Basically, 4 types of data distribution are mainly focused: fix valued data (just only one constant value occurs in normality), discrete distribution, normal distribution and continuous non-normal distribution. We design to use data level counts and normal distribution test to split them base on some statistical methods. Depending on the result of classification, we assign the suitable quality control method or control chart type for each class. Of course, the false alarm rate is considered to balance all data types into comparable level.
Simulation and Analysis of High Breakdown Voltage AlGaN/GaN MOSHEMTs with TiO2/Al2O3 Gate Dielectric
Authors: Li Xiaoping , Wang Jinyan , Cai Jinbao , Liu Yang , Yang Zhen , Zhang Bo , Wang Maojun , Yu Min , Xie Bing , Wu Wengang , Zhang Jincheng , Ma Xiaohua
Published: March 2013

Recently we have demonstrated the thermal oxidized TiO2/Al2O3 as gate dielectric for AlGaN/GaN metal-oxide-semiconductor high-electron-mobility-transistors (MOS-HEMTs) with enhanced breakdown voltage of 490 V compared with 60-100 V breakdown voltage for normal HEMTs. The characteristics of GaN-based MOS-HEMTs with TiO2/Al2O3 gate dielectrics are measured and simulated using Sentaurus Device Software. The significant improvement of breakdown voltage of MOS-HEMTs with TiO2/Al2O3 gate oxide was analyzed. It is shown that the effect of TiO2 on surface electric potential distribution results in the improvement of breakdown voltage. This work will represent a solid basis for improvement of breakdown voltage and enhancement of the device reliability.
An On-Chip EMI Sensor Array
Authors: Su Tao , Huang Yaren , Wang Zixin
Published: March 2013

This paper presents a design of the sensor array that helps to determine the location of the failed circuit on the chip when external EMI is applied to an IC. A scheme of the feedback signal for the failure location detection is developed. The transistor circuit of the sensor cell is designed. The functionality of the design is verified through transistor level simulation.
(Keynote) X-ray Metrology for Advanced Technology Nodes
Authors: Vigliante Assunta , Lin Wayne J.
Published: March 2013

Latest innovations in high brightness X-ray sources, more efficient X-ray detectors combined to the intrinsic capability of X-rays to probe materials at sub nanometer scale are opening new opportunities for the characterization of new materials and structures like FINFETs at the advanced technology nodes. The metrology challenges at 22 nm node and below (ie, shrinking size, thinner films, introduction of new material and 3 D structures) will also results in the development of a new generation of metrology tools and methods for process control. Moreover the transition to 450 mm wafer manufacturing will add challenges related to throughput. As stated by G450C in Albany, the throughput at 450mm for a given metrology has to match the equivalent one at 300mm. For X-ray metrology this requirement will translates in brighter X-ray sources, more efficient optics and detectors in order to speed up the measurements and meet the specifications. In this paper we will discuss new high brightness X-ray sources and the most important applications for X-ray metrology for the next five years.
Path to Better CD-SEM Condition Control for Advanced Technology Nodes
Authors: Cai Bo-Xiu , Huang Yi , Lin Yi-Shih , Li Wen-Hui , Yang Si-Yuan Frank
Published: March 2013

For the past decade in semiconductor manufacturing, technology of critical dimension (CD) metrology hasn’t been advancing as fast as CD downscales. As we reach the verge where metrology uncertainty rather than process capability start to be the bottleneck against tighter CD control, a thorough revisit on metrology tool condition control becomes crucial. CD-SEM in particular is on top of this list due to its complex and delicate physics, multiple-folds interaction with sample, destructive nature and its unique role in critical process development step such as OPC model calibration. In this work we focus on the characterization, evaluation and control of CD-SEM condition drifting aiming to keep current generation tool up with the higher metrology standard.
OCD Sensitivity Study and Parameter Optimization for Oxide-Nitride Spacer Etched Poly
Authors: Wang Xin , Zhang Zhen Sheng , Shi Yaoming , Liu Zhijun , Li Hai Tao , Zhan Yan Kun , Xu Yiping , Lee Charles , Huang Yi
Published: March 2013

Optical critical dimension (OCD) measurement has been widely demonstrated as an essential metrology method for advanced IC process monitoring at 90 nm node and beyond. However, aggressive IC industry scaling requirements and sharply increased process control complexity motivated the development of metrology tools. Oxide - Nitride spacer etched poly, abbreviated as ON-spacer-etch, correlated tightly with channel drive current and leakage control. In this work, the spectroscopic ellipsometry diffraction on ON-spacer-etch gratings was simulated by rigorous coupled wave algorithm (RCWA) method. The sensitivity analysis provided optimal light incident direction and step size for the selected geometric parameters to be used in the practical measurement and spectral library generation. The after-etching inspection (AEI) measurement on ON-spacer-etch targets was taken. The dynamic repeatability and long-term stability tests were conducted to make an evaluation on the tool, while the correlation with reference data and machine noise was discussed in detail. CD extraction demonstrated in this work will help for ramping up yield and controlling cost in high volume manufacturing (HVM).
Endpoint Detection in Plasma Etching Using FFT and SVM
Authors: Han Yi Seul , Shin Sung Hwan , Park Young Kook , Hong Sang Jeen , Han Seung Soo
Published: March 2013

As semiconductor devices are highly integrated, etching control is much more difficult in semiconductor industry. Plasma etching has better performance than wet etching especially in small open area etching. In semiconductor manufacturing industry, the optical emission spectroscopy (OES) is widely used to collect data from plasma chamber. The enormous OES data need to be transformed for accutate endpoint detection. There are some research results regarding endpoint detection in plasma etching using various methods such as Principal Component Analysis (PCA), Partial Least Squares (PLS), etc. In this paper a new approach is proposed for endpoint detection of small open area wafers in plasma etching. The new approach utilizes a Fast Fourier Transform (FFT), which is an efficient algorithm to detect frequency changes in signal, and this property is applied to OES data to detect endpoint in etching process. By applying FFT, noise is reduced compared to PCA data. The data after FFT is used to detect endpoint using Support Vector Machine (SVM). The combination of FFT and SVM performs excellent in terms of endpoint detection, and the performance of proposed FFT/SVM algorithm is compared to the performance of PCA/SVM algorithm.
Development of a Predictive and Preventive Maintenance Demonstration System for a Semiconductor Etching Tool
Authors: Lee Jay , Siegel David , Lapira Edzel Racsa
Published: March 2013

Increasing yield, eliminating unexpected downtime, and reducing maintenance costs are some of the potential benefits that a predictive monitoring system can provide for semiconductor manufacturing. Prior to the implementation of a predictive based condition monitoring approach for critical semiconductor equipment and components, the technology requires further development and validation. A systematic approach for developing a predictive monitoring system is presented, including several key steps that include data pre-processing, feature extraction and selection, health assessment, and component lifetime prediction. The approach is demonstrated on a LAM 2300® Kiyo® conductor etch product, in which data was collected over an 8-month period from a GlobalFoundries Fab in Dresden, Germany. The methodology and predictive health models are demonstrated for an example component from the etching tool, the electrostatic chuck. Both trace signals and metrology data are evaluated for developing the health and prediction models for the electrostatic chuck. The health monitoring models provide a clear and increasing trend, in which the electrostatic health value can be tracked quite well over time. The systematic development framework shows promise and future works looks to further validate the prediction models, and in addition develop commercially viable implementation software from this work.
Defect Losses under Different Processes, Stress, Recovery, and Anneal Conditions
Authors: Duan M. , Zhang Jian Fu , Ji Z. , Zhang W.
Published: March 2013

It is well known that degradation limits device lifetime. Early works were focused on defect generation and it is generally believed that, once a defect is created, it will be there forever. Although some defects can be neutralized after stress, they will recharge when the stress is resumed. Recently, we show that the generated defects themselves are not stable and can be lost. In this work, we investigate defect losses on samples fabricated under different conditions and the loss after different stress, recovery, and anneal conditions. It is found that the defect losses are a generic phenomenon and occur in both plasma SiON and ALCVD SiON/HfSiON stack. It will be shown that the defect losses are insensitive to the level of neutralization during the anneal. The losses have been observed at a temperature as low as 125 oC.
Characterization of Random Telegraph Noise in Scaled High-κ/Metal-Gate MOSFETs with SiO2/HfO2 Gate Dielectrics
Authors: Li Meng , Wang Runsheng , Zou Jibin , Huang Ru
Published: March 2013

In the paper, random telegraph noise (RTN) in high-k/metal-gate MOSFETs is investigated. The RTN in high-k MOSFETs is found different compared to that in SiON MOSFETs, and faces challenges in characterization. Therefore, the characterization method is improved based on clustering and Hidden Markov Model, which greatly enhances the ability to extract RTN with non-negligible “ghost noise” in high-k MOSFETs. The RTN signal and “ghost noise” in devices fabricated by two SiO2/HfO2 stack processes with two different formation methods are compared. It is found that the real RTN signal in SiO2/HfO2 MOSFETs originates from the oxide defects in the HfO2 layer, while the “ghost noise” originates from the SiO2 interfacial layer and has strong dependence on the quality and formation process of interfacial layer.
Effect of Low-Temperature on Endurance Characteristics of SONOS Memory
Authors: Liu Lijuan , Shen Guofei , Cao Gang , Zhang Shunbin , Shi Yanling
Published: March 2013

The endurance characteristics of SONOS nonvolatile memory are investigated in a temperature range from -40°C to 85°C. The erase/program speed is sensitive to the temperature. Low-temperature severely degrades the performance of the SONOS due to its slower program/erase speed and smaller initial voltage. The critical effect is the insufficient Vte in the low-temperature. In this paper, various process improvements and operational optimizations have been proposed to improve the Vte. The experimental results clearly prove that longer Erase/Program(E/P) time and higher voltage can increase the memory window. Smaller channel implant dose and Idac can effectively trade off the program Vtp and erase Vte. Finally, the SONOS memory can be successfully used in the industry application with good reliability and high speed performance.
(Invited) Technological Approaches Towards High Voltage, Fast Switching GaN Power Transistors
Authors: Würfl Joachim , Hilt Oliver , Bahat-Treidel Eldad , Zhytnytska Rimma , Klein Kirill , Kotara Przemyslaw , Brunner Frank , Knauer Arne , Krüger O. , Weyers Markus , Tränkle Günther
Published: March 2013

Approaches towards fast switching GaN devices for applications in power electronics are discussed. First, an overview on the most prominent techniques towards increased breakdown voltage will be given for devices grown on SiC and Si substrates. These tech-niques will then be set in relation to dynamic switching properties at different bias voltage levels. Dynamic switching properties are still lagging behind competing devices, especially if switching at high bias levels is considered. The switching properties are usually expressed by the so-called dynamic on-state resistance. It signifi-cantly depends on technological parameters such as epitaxial layer design and crystalline quality of the buffer layer, passivation layers and, last but not least the lateral device designs (e.g. field plate ar-rangements). A balanced trade-off between all these influencing quantities is shown and correlated to current state of GaN high voltage switching devices.
Electrical Properties and Conduction Mechanism of RRAM With Al/WOX/Cu Structure
Authors: Tao Lu , Kailiang Zhang , Fang Wang , Kuo Sun , Wenxiang Sun , Jinshi Zhao
Published: March 2013

The electrical properties and conduction mechanism of the WOx-based RRAM were investigated in this work. The WOx layer was formed by DC reactive magnetron sputtering on Cu/Ti/SiO2/Si substrate at room temperature. And then RTP was done under 300oC for 30 seconds in oxygen atmosphere. The programming, reading, and reliability behaviors of the device cells were characterized detailedly. The results show that the low programming voltages for SET (1.1 V) and RESET (-0.9 V) process were achieved. The good endurance (>1000) and retention time (104 s) had been demonstrated. In addition, the device is immune to read disturb. The conduction mechanism both in ON and OFF state are oxygen vacancy conductive filament.
Resistive Switching Characteristics of Zinc Oxide Resistive RAM Doped with Nickel
Authors: Wenxiang Sun , Kailiang Zhang , Fang Wang , Kuo Sun , Yinping Miao , Jinshi Zhao
Published: March 2013

Resistive switching characteristics of zinc oxide thin films with nickel doped were investigated in this paper. A device cell with the structure of TiN/ZnO/Ni/ZnO/Pt/substrate was fabricated by radio frequency magnetron sputtering. The cells showed stable bipolar with an on/off ratio of ~104 at a set voltage of 2V. Comparing with TiN/ZnO/Pt RRAM structure, I-V curve results of Ni-doped samples demonstrated that the electrical properties of ZnO films changed, especially Ni significantly decreased the reset current of ZnO films. The influence of annealing was also investigated, the results showed that annealing was helpful to reduce reset current and avoid a high-voltage forming process, and annealing with 400oC is the optimal condition for this structure.
The Optimization of Thermal Flow Field in a Large-Size MOCVD Reactor
Authors: Hu Chih-Kai , Li Tomi T , Lin Yi-Jiun
Published: March 2013

In this paper, the effects of operating conditions in a large-size, vertical and close-spaced reactor for metalorganic chemical vapor deposition are investigated and described by simulation and analysis. The parameters are involved such as space between gas inlet and susceptor (11-20 mm), reactor wall temperature (50-200℃), gas inlet temperature (50-200℃),and chamber pressure (100-760 torr). These listed parameters show that an optimization ideal stagnation flow can be achieved in a large-size close-spaced reactor.
Gate-Modulated Photoresponse in Graphene Field-Effect Transistors
Authors: Wei Zijun , Wang Zhigang , Zhao Huabo , Ye Tianyang , Ren Liming , Guo Jian , Jia Yuehui , Zhang Zhaohui , Fu Yunyi , Huang Ru , Zhang Xing
Published: March 2013

In this paper, we have investigated the photoresponse in a graphene field-effect transistor (FET). We find that significant photocurrents can be detected when the device is illuminated by a laser beam (λ = 633nm). The back-gate can effectively modulate the magnitude and direction of the photocurrent. The possible reasons have been qualitatively analyzed. Our results will provide a better understanding of the electric field distribution in graphene devices, and may also be helpful to find a new way to realize the graphene-based photodetectors.
(Keynote) Smart Systems for a Better Life
Authors: Gessner T. , Vogel M. , Nestler J. , Hiller K. , Kurth S. , Otto T.
Published: March 2013

Micro systems exist as part of daily life almost anywhere - and largely unnoticed. They have also mostly unnoticed, beginning through the last two decades a rapid development, starting from miniaturized single-functional system more and more to a complex system containing an integrated functional diversity. Smart systems with their steadily increasing functional diversity are with their capabilities far beyond such already known (and broadly used) microsystems, only designed and able for the measurement of a single physical, biological or chemical parameter, but already combined with signal processing and actuating abilities. Smart systems integration addresses the demand for miniaturized multifunctional devices and specialized connected and interacting solutions. Multidisciplinary approaches featuring devices for complex solutions and making use of shared and, increasingly, self-organizing resources are among the most ambitious challenges. Thereby the progressive development of smart systems is characterized by their increasing autonomy due to two main effects: the increasing self-sufficient in energy requirements and the less reliant upon external supervision and control.
(Keynote) Solid-State Nanopore Fabrication with Conventional Process
Authors: Liu Zewen , Deng Tao , Chen Jian
Published: March 2013

In this paper, the progress of solid-state nanopores fabrication is reviewed after a brief summary of the basic principle of the new DNA sequencing technology based on solid-state nanopores. The pore-size shrinking technique for the pores with a diameter below 10 nm is highlighted. Based on an analysis on the current works, it can be concluded that the conventional micro-nano processing technology combination with the pore-size shrinking technique are an effective way for mass fabrication of the solid-state nanopores.
(Keynote) Chinas Markets - No Option for German SMEs
Authors: Hippler Heinz-Peter
Published: March 2013

China has reached the champions’ league for export. Today China is one of the most important markets worldwide. From Europe and Germany big global companies are already settled in China. But the German economy is driven by small and medium sized enterprises mainly. Over 90% of all German companies are SMEs with less than 500 employees. Many high tech evolutions are coming from small start-ups. These have much more difficulties to go to China then big players. Chinese business needs all-time presence. SMEs who want to get a food in the Chinese market door have to invest in a branch office at least. Even more efficient is a production subsidiary. Strengths and weaknesses as well as opportunities and risks of the company and the management should be evaluated. For SMEs focused on realistic expectations it is possible to plan the business for short, middle and long term run. In some points Chinese business works like somewhere else in the world: The right technique at the right spot at the right time. Quality is very welcome in China. Strong price discussions signaling high interest and are an honor to a strong partner. China is open for small and medium-sized companies. Province and city government supports foreign investors and potential business partners. Once a partnership is established on equal level for both parties operating with respect and trust, the mutual benefit will succeed.
An Optimization Procedure for Coil Design in a Dual Band Wireless Power and Data Transmission System
Authors: Li Wuxi , Yuan Hang , Xu Wei , Geng Kunling , Wang Guoxing
Published: March 2013

Biomedical implanted electronic devices such as retinal prosthesis and artificial cochlea commonly use coupling inductive coils for power and data transmission. With many parameters to be considered, exhaustive sweeping of these parameters is impractical in physical verification. This paper presents an applicable optimization procedure for coils design in a dual band transmission system proposed by our group. This procedure focuses on the optimization of two pairs of coils based on an overlapping structure which minimizes power-to-signal interference in the data transmission. We applied the optimization procedure to a practical design case, and the result showed that our semi-automatic optimization procedure can achieve both optimal power transmission efficiency and high signal to interference ratio.
A CMOS Potentiostat Circuit for Parallel Direct DNA Sensing
Authors: Dai Tianjun , Zhang Lei , Li Mengwei , Wu Cinan , Liu Zewen
Published: March 2013

An on-chip CMOS potentiostat, including a triangle wave signal generator, a small current signal detector and a potential controller, and its auxiliary circuits are presented for deoxyribonucleic acid (DNA) sensing applications. A fully differential transimpedance amplifier (TIA) with reconfigurable resistors was used for wide range current measurements. An 8×8 pixel array consisting of a 64-pixel rectangular working electrode array with an optimized reference and counter electrode structure is proposed for testing purposes. The design is based on 0.18 μm CMOS technology with a 1.8 V supply. Post-verification measurements show that the scanning signal generator can generate a triangle wave with a tunable frequency when the voltage changes from 300 mV to 1.69 V. The circuit also achieves a large dynamic range of up to 100 dB, and shows very good linearity from 90 pA to 9 μA.
Differentiation of cerebral representation of occlusion and swallowing with fMRI
Authors: Mihai Paul G. , von Bohlen und Halbach Oliver , Lotze Martin
Published: March 2013

Early work on representational specificity and recent findings on temporomandibular joint (TMJ) movement representation raise doubts that a specific swallow representation does exist. Additionally, during cortical stimulation TMJ movements and swallowing show a high overlap of representational areas in the primary motor cortex. It has thus been hypothesized that they overall might share the same neural structures. To differentiate these two movements, we performed a functional MRI (fMRI) study that enabled a direct comparison of functional representation of both actions in the same subject group. Effort during these tasks was controlled by skin conductance response. When balancing effort, we found a comparable neural representation pattern for both tasks but increased resources necessary to perform swallowing in direct comparison between tasks. For the first time, with the usage of fMRI, we demonstrated a representation in the brainstem for swallowing and occlusion. Increased activation for swallowing was observed in bilateral sensorimotor cortex, bilateral premotor and supplementary motor cortex, motor cingulate, thalamus, cerebellar hemispheres, left pallidum, bilateral pons, and midbrain. Peaks of activation in primary motor cortex between both conditions were about 5 mm adjacent. Brainstem activation was found corresponding to the sensory nucleus of the trigeminal nerve, the solitary nucleus for swallowing, and the trigeminal nucleus for occlusion. Our data suggest that cerebral representation of occlusion and swallowing are spatially widely overlapping, differing predominantly with respect to the quantity of neural resources involved. Both brainstem and primary motor representation differ in location with respect to somatotopy and contribution of cranial nerve nuclei.
Acute on chronic exposure to endotoxin is associated with enhanced chemoreflex responses in preterm fetal sheep
Authors: Booth Lindsea C. , Drury Paul P. , Muir Cameron , Jensen Ellen C. , Gunn Alistair J. , Bennet Laura
Published: March 2013

There is increasing evidence that exposure to infection can sensitize the fetus to subsequent hypoxic injury. However, it is unclear whether this involves compromise of the fetal cardiovascular adaptation to acute asphyxia. Chronically instrumented 103-day-old (0.7 gestational age, term is 147 days) fetal sheep in utero were randomized to receive either gram-negative lipopolysaccharide (LPS) as a continuous low-dose infusion for 120 h plus boluses of 1 μg LPS at 48, 72, and 96 h with asphyxia at 102 h (i.e., 6 h after the final LPS bolus) induced by umbilical cord occlusion for 15 min (LPS treated, n = 8), or the same volume of saline plus occlusion (saline treated, n = 7). Fetuses were killed 5 days after occlusion. LPS was associated with a more rapid fall in fetal heart rate at the onset of occlusion ( P < 0.05) and with minimally lower values during occlusion ( P < 0.05). The LPS-treated fetuses had lower fetal mean arterial blood pressure (BP) and greater carotid artery blood flow (CaBF) before occlusion ( P < 0.05) but showed an increase in BP and fall in CaBF to similar values as saline controls during occlusion. There were no differences between the groups in femoral blood flow before or during occlusion. Contrary to our initial hypothesis, acute on chronic exposure to LPS was associated with more rapid cardiovascular adaptation to umbilical cord occlusion.
Investigation of wild-type and mycolactone-negative mutantMycobacterium ulceranson skeletal muscle: IGF-1 protects against mycolactone-induced muscle catabolism
Authors: Dufresne Sébastien S. , Frenette Jérôme
Published: March 2013

Buruli ulcer (BU), which is caused by Mycobacterium ulcerans (MU), is an endemic and neglected tropical disease that affects mostly subcutaneous tissues. Skeletal muscle under infected skin is also subject to serious dysfunctions and contractures. The goal of this study was to investigate the effects of an infection with the wild-type M. ulcerans (WT-MU) or the mycolactone-negative Mycobacterium ulcerans (Mneg-MU) mutant strains on myotubes or fully differentiated skeletal muscles. WT-MU infection decreased by 22% and 29% the maximal muscle force at days 7 and 42 postinfection, respectively, while Mneg-MU induced no decrease at day 7 postinfection and a small but significant 13% decrease in muscle force at day 42. A 13.2-fold and 4.3-fold increase in neutrophil and macrophage concentrations, respectively, was observed on day 42 following the injection of WT-MU. However, the increases in neutrophil and macrophage concentrations were 2.4-fold and 5.5-fold in Mneg-MU. Myoblast proliferation decreased by 20%, myotube diameter by 45%, MyHC levels by 32%, while MuRF-1 levels increased by 22.8% when C2C12 cells and WT-MU were cocultured for 48 h at a multiplicity of infection of 5:1. In contrast, Mneg-MU had no significant effect. Interestingly, the addition of 1,000 ng/ml of IGF-1 to the WT-MU/C2C12 coculture significantly improved all of these biological parameters. The present investigation clearly established that muscle dysfunction and chronic inflammation in the presence of WT-MU are largely caused by the release of mycolactone, and the addition of recombinant IGF-1 was sufficient to alleviate some of the antiproliferative and atrophic effects of mycolactone.
Active muscle regeneration following eccentric contraction-induced injury is similar between healthy young and older adults
Authors: Buford Thomas W. , MacNeil R. Gavin , Clough Launa G. , Dirain Marvin , Sandesara Bhanuprasad , Pahor Marco , Manini Todd M. , Leeuwenburgh Christiaan
Published: March 2013

Repair of skeletal muscle after injury is a key aspect of maintaining proper musculoskeletal function. Studies have suggested that regenerative processes, including myogenesis and angiogenesis, are impaired during advanced age, but evidence from humans is limited. This study aimed to compare active muscle regeneration between healthy young and older adults. We evaluated changes in clinical, biochemical, and immunohistochemical indices of muscle regeneration at precisely 2 (T2) and 7 (T3) days following acute muscle injury. Men and women, aged 18-30 and ≥70 years, matched for gender and body mass index, performed 150 unilateral, eccentric contractions of the plantar flexors at 110% of one repetition maximum. Data were analyzed using analysis of covariance, adjusted for gender, habitual physical activity, and baseline level of the outcome. A total of 30 young ( n = 15; 22.5 ± 3.7 yr) and older ( n = 15; 75.8 ± 5.0 yr) adults completed the study. Following muscle injury, force production declined 16% and 14% in young and older adults, respectively, by T2 and in each group, returned to 93% of baseline strength by T3. Despite modest differences in the pattern of response, postinjury changes in intramuscular concentrations of myogenic growth factors and number of myonuclear (4′,6-diamidino-2-phenylindole+ and paired box 7+) cells were largely similar between groups. Likewise, postinjury changes in serum and intramuscular indices of inflammation (e.g., TNF-α and monocyte chemoattractant protein-1) and angiogenesis (e.g., VEGF and kinase insert domain receptor) did not differ significantly between groups. These findings suggest that declines in physical activity and increased co-morbidity may contribute to age-related impairments in active muscle regeneration rather than aging per se.
Antibody and CD8+ T cell memory response to influenza A/PR/8/34 infection is reduced in treadmill-exercised mice, yet still protective
Authors: Warren Kristi , Thompson Nicholas , Wannemuehler Michael , Kohut Marian
Published: March 2013

Moderate exercise may decrease the severity of influenza infection and reduce lung viral load. The possibility that an exercise-associated reduction in lung viral load early in infection could contribute to decreased serum antibody and reduced memory response were investigated. BALB/c mice exercised for 8 wk and were then infected with influenza A/PR/8/34 (intranasal route). Influenza-specific serum antibody was assessed for 6 mo post primary infection, at which time mice were infected again with influenza A/PR/8/34. After primary infection, exercise reduced morbidity/mortality, attenuated lung cytokines, and decreased serum anti-influenza IgG and IgG2a from day 14 to day 180 post primary infection. After secondary infectious challenge, exercised mice did not show any signs of illness, but had reduced serum anti-influenza IgG and IgG2a, increased IgG1, and reduced influenza-specific recruited and resident CD8+ granzyme B+ T cells within the lungs. When influenza virus was administered by an intraperitoneal route during primary infection, exercise did not alter serum anti-influenza IgG, IgG1, or IgG2a, suggesting the exercise effect was specific to the lung environment. Exercise-induced enhancement of respiratory host defense to primary influenza infection results in decreased serum antibody and lung CD8+ T cell memory response, but does not compromise resistance to secondary infectious challenge.
A Novel Method for Classifying Body Mass Index on the Basis of Speech Signals for Future Clinical Applications: A Pilot Study
Authors: Lee Bum Ju , Ku Boncho , Jang Jun-Su , Kim Jong Yeol
Published: March 2013

Obesity is a serious public health problem because of the risk factors for diseases and psychological problems. The focus of this study is to diagnose the patient BMI (body mass index) status without weight and height measurements for the use in future clinical applications. In this paper, we first propose a method for classifying the normal and the overweight using only speech signals. Also, we perform a statistical analysis of the features from speech signals. Based on 1830 subjects, the accuracy and AUC (area under the ROC curve) of age- and gender-specific classifications ranged from 60.4 to 73.8% and from 0.628 to 0.738, respectively. We identified several features that were significantly different between normal and overweight subjects (P<0.05). Also, we found compact and discriminatory feature subsets for building models for diagnosing normal or overweight individuals through wrapper-based feature subset selection. Our results showed that predicting BMI status is possible using a combination of speech features, even though significant features are rare and weak in age- and gender-specific groups and that the classification accuracy with feature selection was higher than that without feature selection. Our method has the potential to be used in future clinical applications such as automatic BMI diagnosis in telemedicine or remote healthcare.
Microwave-Assisted Extraction Studies of Target Analyte Artemisinin from Dried Leaves of Artemisia annua L.
Authors: Misra Himanshu , Mehta Darshana , Mehta B. K. , Jain D. C.
Published: March 2013

Artemisia annua L. (Asteraceae) is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. Conventional methods for the extraction of artemisinin from A. annua including solvent extraction, Soxhlet extraction, and heat reflux extraction are characterized by long extraction times and the consumption of large volume of solvents. A simple, rapid, and precise microwave-assisted extraction process was optimized for fast sample preparation for the faster quantitative determination of artemisinin, potential new generation antimalarial drug, from dried leaves of Artemisia annua L. A simple experiment was designed for the optimization of the appropriate solvent under same extraction conditions. The selected appropriate solvent was then standardized for various different extraction variables. The major parameters studied showed effects on extraction efficiency including processing time, strength of microwave, moisture content, volume and nature of the solvent. The most favorable conditions were obtained by using plant material of 25 mesh (particle size) extracted with acetone for 120 seconds at 160 W (i.e., 20% of total power). Quantitative analysis was performed using thin-layer chromatography coupled with a densitometer (TLC densitometry). The results showed that MAE can be used as an efficient and rapid method for the extraction of the active components from plants.
Some Properties of the -Extension of the -Adic Gamma Function
Authors: Menken Hamza , Körükçü Adviye
Published: March 2013

We study the -extension of the -adic gamma function . We give a new identity for the -extension of the -adic gamma in the case . Also, we derive some properties and new representations of the -extension of the -adic gamma in general case.
Parental Factors Associated with Mexican American Adolescent Alcohol Use
Authors: Mogro-Wilson Cristina
Published: March 2013

The purpose of this study is to further the understanding of how parenting and the relationship between the parent and the youth influence adolescent alcohol use in Mexican American families, with particular attention to acculturation. Results indicated that parental warmth is a strong factor in predicting adolescent alcohol use among Mexican adolescents. The parent-youth relationship played an important role in lowering alcohol use for Mexican American youth. Acculturation has an impact on the level of warmth, control, and the parent-youth relationship for Mexican American families. Findings indicate that there are unique family mechanisms for Mexican American families that should be considered when developing prevention and treatment options.
Mechanism of and Therapeutic Strategy for Atrial Fibrillation Associated with Diabetes Mellitus
Authors: Lin Yubi , Li Hairui , Lan Xianwu , Chen Xianghui , Zhang Aidong , Li Zicheng
Published: March 2013

Diabetes mellitus (DM) is one of the most important risk factors for atrial fibrillation (AF) and is a predictor of stroke and thromboembolism. DM may increase the incidence of AF, and when it is combined with other risk factors, the incidence of stroke and thromboembolism may also be higher; furthermore, hospitalization due to heart failure appears to increase. Maintenance of well‐controlled blood glucose and low levels of HbA1c in accordance with guidelines may decrease the incidence of AF. The mechanisms of AF associated with DM are autonomic remodeling, electrical remodeling, structural remodeling, and insulin resistance. Inhibition of the renin‐angiotensin system is suggested to be an upstream therapy for this type of AF. Studies have indicated that catheter ablation may be effective for AF associated with DM, restoring sinus rhythm and improving prognosis. Catheter ablation combined with hypoglycemic agents may further increase the rate of maintenance of sinus rhythm and reduce the need for reablation.
Osteosarcoma in Adult Patients Living with HIV/AIDS
Authors: Marais Leonard C. , Ferreira Nando
Published: March 2013

Background. HIV infection has reached epidemic proportions in South Africa, with an estimated prevalence of 21.5% in adults living in the province of KwaZulu-Natal. Several malignancies have been identified as part of the spectrum of immunosuppression-related manifestations of HIV infection. Very few reports, however, exist regarding the occurrence of non-AIDS-defining sarcomas in the extremities or limb girdles. Methods. A retrospective review was performed on all adult patients, between the ages of 30 and 60 years, with histologically confirmed osteosarcomas of the appendicular skeleton referred to a tertiary-level orthopaedic oncology unit. Results. Five out of the nine patients (62.5%) included in the study were found to be HIV positive. The average CD4 count of these patients was 278 (237–301) cells/mm3, indicating advanced immunological compromise. Three of the malignancies in HIV-positive patients occurred in preexisting benign or low-grade tumours. Conclusion. A heightened index of suspicion is required in HIV patients presenting with unexplained bone and joint pain or swelling. Judicious use of appropriate radiological investigation, including magnetic resonance imaging of suspicious lesions and timely referral to an appropriate specialized orthopaedic oncology unit, is recommended.
Retrograde Approach to a Diverticular Kidney Stone through a Vesicoureteral Cohen's Reimplantation: A Novel Surgical Technique
Authors: Khalil Fahd , Tligui Mohamed , Traxer Olivier
Published: March 2013

Cohen's technique is the standard treatment of vesicoureteral reflux in children. Its disadvantage is still the classic difficulty in subsequent retrograde ureteral access, requiring the use of percutaneous techniques in the treatment of kidney stones. We describe a novel surgical technique for retrograde catheterization of an adult ureter by a flexible ureterorenoscope, thereby facilitating the treatment of a symptomatic diverticular kidney stone. We compare our technique to other methods described in the literature.
Supplementation with High Doses of Vitamin D to Subjects without Vitamin D Deficiency May Have Negative Effects: Pooled Data from Four Intervention Trials in Tromsø
Authors: Jorde Rolf , Strand Hutchinson Moira , Kjærgaard Marie , Sneve Monica , Grimnes Guri
Published: March 2013

Data were pooled from four randomized clinical trials with vitamin D performed in Tromsø with weight reduction, insulin sensitivity, bone density, and depression scores as endpoints. Serum lipids, glycated hemoglobin (HbA1c), and high sensitivity C-Reactive Protein, (HS-CRP) were measured at baseline and after 6–12 months of supplementation with vitamin D 20 000 IU–40 000 IU per week versus placebo. A total of 928 subjects who completed the interventions were included. At baseline the mean serum 25-hydroxyvitamin D (25(OH)D) level in those given vitamin D was 55.9 (20.9) nmol/L and the mean increase was 82.4 (40.1) nmol/L. Compared with the placebo group there was in the vitamin D group at the end of the studies a slight, but significant, increase in HbA1c of 0.04%, an increase in HS-CRP of 0.07 mg/L in those with serum 25(OH)D < 50 nmol/L, and in those with low baseline HDL-C and serum 25(OH)D < 50 nmol/L a slight decrease serum HDL-C of 0.08 mmol/L (P<0.05). No serious side-effects were seen. In conclusion, in subjects without vitamin D deficiency, there is no improvement in serum lipids, HbA1c, or HS-CRP with high dose vitamin D supplementation. If anything, the effect is negative.
Evaluation ofIn VitroAnti-Inflammatory Activities and Protective Effect of Fermented Preparations of Rhizoma Atractylodis Macrocephalae on Intestinal Barrier Function against Lipopolysaccharide Insult
Authors: Bose Shambhunath , Kim Hojun
Published: March 2013

Lipopolysaccharide (LPS), a potent inducer of systemic inflammatory responses, is known to cause impairment of intestinal barrier function. Here, we evaluated thein vitroprotective effect of an unfermented formulation of Rhizoma Atractylodis Macrocephalae (RAM), a traditional Chinese herbal medicine widely used in the treatment of many digestive and gastrointestinal disorders, and two fermented preparations of RAM, designated as FRAM-1 (prepared in Luria-Bertani broth) and FRAM-2 (prepared in glucose), on intestinal epithelial cells (IECs) against LPS insult. In general, fermented formulations, especially FRAM-2, but not unfermented RAM, exerted an appreciable protective effect on IECs against LPS-induced perturbation of membrane resistance and permeability. Both fermented formulations exhibited appreciable anti-inflammatory activities in terms of their ability to inhibit LPS-induced gene expression and induced production of a number of key inflammatory mediators and cytokines in RAW 264.7 macrophage cells. However, in most cases, FRAM-2 exhibited stronger anti-inflammatory effects than FRAM-1. Our findings also suggest that suppression of nuclear factor-κβ(NF-κβ) activity might be one of the possible mechanisms by which the fermented RAM exerts its anti-inflammatory effects. Collectively, our results highlight the benefits of using fermented products of RAM to protect against LPS-induced inflammatory insult and impairment in intestinal barrier function.