bluuebunny/crossref_metadata_2025 huggingface dataset:
Endpoint Detection for Single Layer Plasma Etch Using Hybrid Fuzzy Inference Systems
Authors: Shin Sung-Hwan , Noh Ho-Taek , Kim Dong-Ill , Park Young-Kook , Han Seung-Soo
Published: March 2014

The need for the accurate endpoint detection (EPD) technique in plasma etching process is increasing in the semiconductor industry for yield improvement and higher device performance. To monitor and analyze plasma process, the one of the most popular sensor is optical emission spectroscopy (OES). The OES can collect optical data emitted from plasma in the processing chamber and these data can be used in diverse methods for monitoring and analyzing plasma status. In this paper, a fuzzy inference system is applied for the endpoint detection using OES data. The fuzzy inference system is an interpretation method of uncertain data set. The normal etching stage and over-etching stage is classified by the fuzzy inference system using OES data. The proposed method successfully detected endpoint of silicon oxide film etching. The performance comparison between fuzzy inference system with linear regression method and with polynomial regression method is also investigated.
Spectral Sensitivity Analysis of OCD Tool for Sub 40 Nm Process
Authors: Wang Xin , Gao Fu , Huang Kun , Zhang Zhen sheng , Shi Yaoming , Xu Yiping
Published: March 2014

Since the measurement precision of OCD (Optical Critical Dimension) technology highly depends on the optical hardware configuration, spectra types, and inherently interactions between the incidence of light and various materials with various geometrical structures, here a method is introduced for seeking the most sensitive measurement configuration to enhance the metrology precision and to reduce the noise impact to the greatest extent. In seeking the best mode and spectrum type for data collection, system noise of tools were estimated based on hardware precision. All spectrum types (e.g. SE, SR, Mueller matrix) were normalized for comparability. The sensitivity of different normalized spectra modes with several hardware configurations of incidence angles and azimuth angles were investigated. The optimal hardware measurement configuration and spectrum parameter can be identified. The minimum parameter tolerance of a given model can be retrieved by theoretical simulations. Poly-silicon (P2-ET) models of 28 nm nodes were constructed to validate the algorithms. The best measurement mode was selected. This method can provide guidance to the measurement precision before measuring actual device CDs.
A Study on Average-Range G.R.R Method Application on Wafer Field Metrology
Authors: Cao Yan , Gong Tai. Cheng , Yu Yan. Ju , Chang Kai. Yuan , Chien Wei. Ting.
Published: March 2014

Gauge Repeatability and Reproducibility (Gauge R&R , G.R.R) is of great importance for checking measurement system precision, traditional average-range G.R.R test involves equipment variation (EV) and appraiser variation (AV), which is not appropriate for current modern automatic measurement tools. In this paper, we designed different test experiments on film thickness (THK) and critical dimension (CD) metrology and statistically analyzed different variances impact on G.R.R. From THK G.R.R experiment ANOVA analysis, it can be seen that time interval and measurement process have no significant effect on G.R.R result, and the equipment repeatability variation is the major variation source. From CD G.R.R experiment ANOVA analysis, it can be checked that, G.R.R has significant time dependence of data collection due to test wafer changed. As a conclusion, not only appraiser’s variation but also time interval has less impact on metrology G.R.R of semiconductor wafer manufacturing process.
Integrating the Quadrupole Mass Spectrometer, Optical Emission Spectroscopy and Langmuir Probe as a Plasma Characterization Tools for ECR-CVD with a-Si:H
Authors: Hu L.C. , Wang C. J. , Lin Y. W. , Wei T. C. , Lee C.C. , Chang J. Y. , Chen I.C. , Li Tomi T.
Published: March 2014

We present the application of quadrupole mass spectrometer (QMS), optical emission spectroscopy (OES), and Langmuir probe (LP) as an integrated technique for plasma characterization of the process during electron cyclotron resonance chemical vapor deposition (ECR-CVD) of hydrogenated amorphous silicon (a-Si:H). The main aim of this study was to investigate the use of QMS to determine the relationship between plasma and thin film characteristics, in particular microstructure parameter (R*) and hydrogen content (CH). The OES was used to assist the QMS in measuring the light and simple radicals, such as the H, Si and SiH, and the associated physical plasma properties which include electron density (Ne), electron energy (Te) and sheath potential (Vs) would be studied with the Langmuir probe. The effects of the two ECR-CVD parameters, namely the power density (1 ~ 4 w/cm2) and hydrogen dilution ratio (H2/SiH4, 0 ~ 25) were discussed. The results indicated that there is a very obvious difference in QMS analysis between plasma and gas, and it is due to the fact that the QMS analysis of plasma is accompanied with the vapor and surface reactions. Therefore, the consumption of parent molecule (SiH4) needed to be considered. The TIMS (Threshold ionization mass spectrometry) method which is usually applied to estimate the relative density trends of the ground-state silane radicals (SiHx, x < 4) was used in this study. It was found that increasing power density and hydrogen dilution ratio would lead to higher electron density and more SiH2 generated in the plasma. Furthermore, when comparing with the TIMS analysis reported by other authors, we found the ratio of SiH2 to SiH3 from QMS could be considered as a better indicator of film quality for R*.
Investigation of Current Density and Hotspot Temperature Distribution Effects on P-Channel LDMOSFET Unclamped Inductive Switching (UIS) Test
Authors: Kurniawan Erry Dwi , Pramudyo Antonius Fran Yannu , Kumar Ankit , Yang Shao-Ming , Sheu Gene
Published: March 2014

Unclamped Inductive Switching (UIS) is a very high stress test used for characterizing the ruggedness in terms of the maximum avalanche energy can be handled by the device. Optimizing the design for better reliability and ruggedness of power MOSFET was studied. In this paper, we investigated effects of current density and hotspot temperature distribution during unclamped inductive switching (UIS) test for P-channel LDMOSFET. It is shown that the simulation results are found to be in good correlation between the maximum avalanche energy handling capability and identification of the mechanism of device-failure (current density distribution effects and hotspot temperature location). Uniformity of current density in each finger of the device can help to improve the maximum avalanche energy handling capability. If current density distribution and temperature hotspot region effects can be suppressed more uniform in each finger of the critical regions, the device is expected to sustain higher avalanche energy during stress.
The Single-Electron Transfer in Polysilicon-Oxide-Nitride-Oxide-Silicon Devices
Authors: Sheng Yingxiao , Guo Yuhan , Ji Xiaoli , Liao Yiming , Yan Feng
Published: March 2014

In this study, the low voltage CHEI program is used to achieve single electron injection in nitride layer of nano-scaled SONOS (polysilicon-oxide-nitride-silicon) devices. By investigating various CHEI conditions and different temperature, the best single electron transfer condition is determined. Under this condition, the single electron induced current steps are in good agreement with theoretical result.
Capacitance-Voltage Characteristics of Symmetric Stacked Bonding Structure in 3D Integration
Authors: Li Man , Guo Yufeng , Lin Hong , Ji Xincun , Xia Xiaojuan , Wang Bin
Published: March 2014

Stacked bonding is one of the most promising approaches to realize three-dimensional integration. In this paper, an analytical model is proposed for the low frequency and high frequency capacitance-voltage characteristics of the symmetric stacked bonding structure. The model is verified by the agreements between the analytical results and numerical simulation results using MEDICI, a two-dimensional semiconductor device simulator. Then, the influence of the doping concentration, oxide thickness and flat-band voltage on the capacitance-voltage characteristics under various bias conditions is researched. This work carries on an approach for the non-destructive characterization of the symmetric stacked bonding structure in three-dimensional integration.
Modeling of Subthreshold Characteristics for Double Gate MOSFET Using Neural Networks and Genetic Algorithm
Authors: Cho Edward Namkyu , Shin Yong Hyeon , Moon Pyung , Yun Ilgu
Published: March 2014

As the metal-oxide-semiconductor field-effect transistor (MOSFET) technology has been developed, the short-channel effects become significant. To overcome these limitations, double gate (DG) MOSFET has been considered and predicting the device characteristics according to device parameters has been important. In this paper, we present the neural networks (NNET) modeling methodology to predict subthreshold characteristics such as threshold voltage (V

TH
) and subthreshold swing (SSUB
) for DG MOSFET. After the NNET model is established, the genetic algorithm (GA) is used to find the device parameters’ design space.
(Invited) SiC and GaN High Voltage Power Devices and Fabrication Processes
Authors: Chow Tat-Sing Paul
Published: March 2014

The present status of the development and commercialization of SiC and GaN power devices for power electronics applications is presented. The fabrication processes for vertical SiC power MOSFETs and lateral GaN power HEMTs are also discussed.
An Increasing High Resistance State Phenomenon in Al/VOx/Cu Resistive Switching Device
Authors: Sun Kuo , Zhang Kailiang , Wang Fang , Sun Wenxiang , Lu Tao , Wang Baolin , Cheng Wenke
Published: March 2014

In this paper, we reported increasing high resistance state (HRS) phenomenon of Al/VOx/Cu resistive random access memory (RRAM). The current of HRS became lower in current-voltage (I-V) curves and resistance of HRS gradually increased from a lower pristine sate to a higher HRS during cycling operation. Schottky emission theory was employed to investigate the HRS conduction. We found that the slope of HRS I-V curves on ln(J) and sqrt(V) plot decreased after cycling operation. According to Schottky emission theory, we concluded that generation of AlOx layer between Al electrode and VOx film was the cause of increasing HRS resistance. We finally verify the conclusion by data retention under constant voltage stress.
Bipolar Uniformity in Al/TiOx/Al Resistive Switching Memory
Authors: Shao Xing Long , Chen Ran , Zhou Li Wei , Chen Chang Jun , Wang Jian Yun , Jiang Hao , Zhang Xue Mei , Liang Yuan , Zhang Kailiang , Zhao Jinshi
Published: March 2014

Bipolar resistive switching property was studied in Al/TiOx/Al structure. This structure exhibits uniform high resistance and low resistance among cell-to-cell test. The switching mechanism ascribes to space-charge-limited conduction. On the other hand, Al/TiOx/Cu sample was deposited as a reference. This structure shows non-uniform variation. The reasons for uniformity of Al/TiOx/Al sample and non-uniformity of Al/TiOx/Cu sample were demonstrated in this work.
(Invited) Passivation of Al2O3/n, p-In0.53Ga0.47 as Interfaces: Influence of Plasma Enhanced Atomic Layer Deposition Aluminum Nitride with Various Plasma Powers
Authors: Chang Edward Yi , Luc Q H , Trinh H D , Lin Y C
Published: March 2014

Plasma enhanced atomic layer deposition (PEALD) aluminum nitride (AlN) is attracting great interests as an advanced technique for high-k/III-V interfacial passivation. In this study, we demonstrate the effects of PEALD-AlN layer deposition plasma powers on the electrical properties of both n-type and p-type In0.53Ga0.47As based metal oxide semiconductor capacitors (MOSCAPs). By using PEALD-AlN as interfacial passivation layer (IPL) at the Al2O3/n, p-In0.53Ga0.47As interface, noticeable enhancement of electrical characteristics including small capacitance-voltage (C-V) hysteresis, small frequency dispersion values, and low interface state densities (Dit) have been observed. After performing 5 cycles of PEALD-AlN IPL at optimized plasma power of 150 W, multifrequency C-V responses exhibit excellent behaviors for both n-type and p-type Al2O3/AlN/In0.53Ga0.47As MOSCAPs. The Dit values are extracted to be 5.3 × 1011 – 1.2 × 1012 cm-2 eV-1 and 1.6 × 1011 - 2.7 × 1011 cm-2 eV-1 at the trap energy level of 0.47 – 0.4 eV and 0.2 – 0.26 eV above the edge of valence band (EV) for n-type and p-type MOSCAPs, respectively. X-ray photoelectron spectroscopy (XPS) analysis reveals that the enhancement of Dit values cannot be fully explained by the reduction of native oxides at the InGaAs surfaces. The original reason of interface defects states is attributed to the surface dangling bonds that were passivated by the polycrystalline PEALD-AlN passivation layer as illustrated in the high resolution transmission electron microscopy (HRTEM) image.
Absorption of Optical Microcavity in the Infrared Spectral Region
Authors: Lv Yufei , Jiang Wenjing , Ou Wen , Chen Tao
Published: March 2014

This paper describes an air Fabry-Perot (FP) cavity which is used in the infrared (IR) detector. When the distance of the FP cavity is wavelength-sized, it can store photons for almost a millisecond while they bounce up and down between the mirrors. Compared with another filled material, the air cavity not only gets high IR absorption when the cavity thickness is quarter wavelength, but also has much smaller thermal capacity and thermal time, which can improve the responsivity and detectivity of the IR detectors. An air FP cavity has been fabricated, with a thick metal mirror at bottom and a special sandwich film in the top served as absorption layer and semitransparent reflector. The materials and thickness are tested to optimize the absorption. According to the results, the best structure has been obtained, and the test results show that the IR absorption of this structure can reach to 85%.
(Invited) Tunable RF MEMS and Its Applications
Authors: Liu Zewen , Liu Huiliang , Sarrazin Julien
Published: March 2014

With fast development of mobile communication technology, the increasingly complex communicating environment and the crowded spectrum have raised stringent requirements on the RF front-end performance. In this paper, the influence of human body on the communication performance is analyzed. In particular, it is shown that the antenna input impedance faces huge variation in the frame of body-centric devices. Consequently, automatic impedance matching appears to be crucial to improve the performance withstand the inconstant environment. The investigation of key tunable components of RF MEMS is therefore presented. A variable capacitor with symmetric balanced structure is designed to achieve a large capacitance tuning ratio and a remarkable linearity of the C-V response. The proposed RF MEMS variable capacitor was modeled and simulated. The results show a linearity factor of 99.82% in C-V response and a large tuning ratio of 480% in a low actuation voltage range from 0V to 16.3V.
(Invited) The Journey of the DMD Pixel Design Evolution
Authors: Gong Cuiling
Published: March 2014

The Digital Micromirror Device (DMD) has enabled the world’s top display products ranging from large cinema projectors to small pico projectors that can fit in smartphones. This paper will walk through the journey of the DMD pixel design evolution from the original digital micromirror concept to the most popular FTP pixel design. The motivations, challenges and impacts of major design changes of four generations of DMD pixels will be discussed including pixel size shrink from 17μm pixel to 10.8μm pixel and tilt angle increase from 10 to 12 degrees.
(Invited) Reliability Aspects of Advanced IC Technology with ESD and Anti-Radiation Capabilities
Authors: Hu David Yu , Chen C Z
Published: March 2014

Today's IC design squeezes millions of gates and 100s ofproven blocks into a single SoC chip, huge efforts have ever been put together into aftermath chip verifications, testing and debugging processes. Failure analysis such as ESD damages, and/or together with SEU (single event upset) by outer space radiations has also become rather impractical. Killer issues arising from intrinsic and extrinsic charge built ups can no longer be prevented by embedded ESD devices of I/O circuit itself. This work will first summaries the rising trend of ESD damages other than human body model (HBM) and machine model (MM) from external sources, also the intrinsic defects from the silicon materials and the associated malfunctions caused by design and backend integrations, then it intends to address a much overlooked 'design for reliability' in line with the DFM and DFY on 65nm technology and below with focus on the less reported CDM (charged device model) ESD damages. Capabilities of anti-radiation effect will be discussed in this work.
Challenges and Novel Solutions for SoC Verification
Authors: Oddone Riccardo , Chen Liang
Published: March 2014

Hundred million gates SoC designs are all over the place with the trend of doubling the scale in up-coming years. Meanwhile time-to-market makes the situation even more difficult. More and more effort has been allocated onto SoC verification in order to tackle the challenges, including the improvement of software-based verification performance, formal verification, hardware acceleration as well as unified verification. But innovation is still needed, as the existing solution won’t be able to handle efficiently of the increasing design size. This paper will first try to address all major issues which would challenge the SoC verification execution as well as quality. At the second part of this paper, we will discuss how Cadence addresses these challenges including, but not limited to, early software development, metric driven verification, formal verification application, Hardware/Software integrated validation and low power. Through close partnership with major industry leaders, Cadence’s solution has been proven to provide a substantial turn-around time reduction while maintaining high quality of result for various SoC projects.
Top Level Bus Estimation for Hierarchical Design
Authors: He Ou , Pu Suoming , Guo Yao
Published: March 2014

As technology advanced into deep sub-micron era, hierarchical design is employed more and more to overcome the growing complexity. Top level timing is a key challenge in deciding the chip performance and time to market. Data bus talks between sub-modules are considered as the bottleneck for top physical designer. An early estimation on these buses will provide good evidence for pipelining in front-end design and buffering in back-end design and also guide the later-on routing for the related nets. This paper proposed a fast estimation algorithm to model the routing of bus talks between sub-modules. First, a grading step is used to decide the criticality for each data talk, according to their bus width and timing criticality. Then, a new connection model is put forward to simplify routing channels on top level without losing too much accuracy. After the simplification, an undirected graph will be built to describe all the routing blockages. Therefore, finding a point-to-point path avoiding blockages on top level becomes polynomial time complexity and the optimum is achievable. Congestion is considered as well. Compared with recent grid-based work which also approximates path finding problem, the proposed graph is smaller and thus faster. Using the path finder, all the data talks will be dynamically estimated one by one at last. Taking practical designs as benchmarks, the algorithm runs steady and fast for the current design scale. Moreover, the undirected graph in this work can be extended to solve other issues as well.
Efficient and Robust Synthesis of Phase-Shifting Masks in Optical Lithography
Authors: Lv Wen , Wei Haiqing , Liu Shiyuan
Published: March 2014

Phase-shifting masks (PSMs) are extensively used in semiconductor industry to push the limit of optical lithography. Their synthesis is generally performed via an optimization method under the nominal process condition, and the synthesis process is time-consuming. In this work, we apply a statistical strategy to optimize the average performance with respect to process fluctuations to enhance the robustness of the synthesized PSM pattern, and employ a cascadic multigrid algorithm to improve its computational efficiency. Moreover, we investigate and discuss the impact of the initial pattern on the synthesized result.
The Neurology of Proverbs
Authors: Van Lancker Diana
Published: March 2014

Although proverb tests are commonly used in the mental status examination surprisingly little is known about either normal comprehension or the interpretation of proverbial expressions. Current proverbs tests have conceptual and linguistic shortcomings, and few studies have been done to investigate the specific effects of neurological and psychiatric disorders on the interpretation of proverbs. Although frontal lobes have traditionally been impugned in patients who are “concrete”, recent studies targeting deficient comprehension of non literal language (e.g. proverbs, idioms, speech formulas, and indirect requests) point to an important role of the right hemisphere (RH). Research describing responses of psychiatrically and neurologically classified groups to tests of proverb and idiom usage is needed to clarify details of aberrant processing of nonliteral meanings. Meanwhile, the proverb test, drawing on diverse cognitive skills, is a nonspecific but sensitive probe of mental status.
Biological and Quantitative Issues in Neuropsychiatry
Authors: Berrios G. E. , Dening T. R.
Published: March 2014

During the recent resurgence of interest in neuropsychiatry, rapid technological advances have outpaced developments in the underlying theoretical framework. Neurophilosophy has tended to overlook clinical problems. This paper aims to redress the balance by examining a number of conceptual issues. Two groups of problems are considered: those related to brain functioning and psychiatric symptoms, and those related to the measurement of symptoms and their statistical analysis. It is emphasized that psychiatric symptoms appear to reflect the modular organization of the brain; and the particular psychiatric symptomatology associated with individual neurological diseases may be more distinct than is generally assumed, both cross-sectionally and over time.
Varieties of Pathological Self-Mutilation
Authors: Favazza Armando R. , Rosenthal Richard J.
Published: March 2014

Pathological self-mutilation appears as a non-specific symptom as well as a specific syndrome. Since psychotic persons may commit horrifying acts, such as enucleation of an eye or amputation of a body part, identification of high risk patients is crucial. Stereotypical self-mutilation, such as head banging and biting off of fingertips, is associated with mental retardation and with the syndromes of Lesch-Nyhan, deLange, and Tourette. This type of self-mutilation is the focus of biological research or endorphins and on dopamine receptors. Skin cutting and burning, the most common type of self-mutilation, is often associated with personality disorders, post-traumatic stress disorder, and multiple personality disorder. When cutting and burning become established as responses to disturbing psychological symptoms on environmental events, a specific Axis I impulse disorder known as Repetitive Self Mutilation may be diagnosed. Patients with this newly identified syndrome may alternate their direct acts of self-mutilation with eating disorders and episodic alcoholism.
Motor Habits in Visuo-manual Tracking: Manifestation of an Unconscious Short-Term Motor Memory?
Authors: Hufschmidt Andreas , Deuschl Günther , Locking Carl Hermann
Published: March 2014

Normal subjects were tested in short, repetitive trials of a tracking task, with an identical shape of target movement being used throughout one session. Analysis of the net error curves (pursuit minus target movement) revealed that subjects regularly exhibit a remoteness effect: neighbouring trials were more similar than distant ones. The effect is demonstrated to be stronger in the absence of visual cues, and was found to be absent in a patient with complete loss of proprioception when he was performing without visual feedback as well. The results are discussed in terms of a short term memory store contributing to unconscious movement habits in tracking. This may represent part of the motor learning process working together with conscious visuo-motor control mechanisms. Its function is probably related to the acquisition of automatic movements.
The Categorical Organization of Semantic and Lexical Knowledge in the Brain
Authors: Gainotti Guido
Published: March 2014

In recent years several papers have shown that different verbal and non-verbal semantic categories can be selectively disrupted by brain damage and that consistent anatomical localizations correspond to each category-specific semantic disorder. This paper aims to suggest that the brain regions typically damaged in a given type of category-specific semantic disorder might be critically involved in processing the kind of information which mainly contributes to organizing that semantic category and to distinguishing among its members. This general hypothesis is discussed taking into account: (a) comprehension and production of object names (nouns) and of action names (verbs) in agrammatic and in anomic aphasic patients; (b) verbal and non-verbal identification of body parts; (c) verbal and non-verbal identification of living beings and of man made artefacts.
Metabolic Characteristics of Oxcarbazepine (®Trileptal) and their Beneficial Implications for Enzyme Induction and Drug Interactions
Authors: Faigle Johann W. , Menge Guenter P.
Published: March 2014

Hepatic oxygenases of the cytochrome P-450 family play a major role in the clearance of various anti-epileptic drugs. These enzymes are susceptible both to induction and to inhibition. Phenytoin, carbamazepine (CBZ), primidone, and phenobarbitone, for instance, are potent enzyme inducers. Other drugs, such as chloramphenicol, propoxyphene, verapamil, and viloxazine, inhibit cytochrome P-450. Pharmacokinetic behaviour is thus often altered, especially in combined medication, so that the dosage has to be re-adjusted if an optimum therapeutic outcome is to be ensured. Oxcarbazepine (OXC) is a keto analogue of CBZ. In the human liver the keto group is readily reduced, and the resulting monohydroxy metabolite is cleared by glucuronidation. The two enzymes mediating these reactions, i.e. aldo-keto reductase and UDP-glucuronyltransferase, do not depend on cytochrome P-450. The monohydroxy metabolite is the major active substance in plasma. Its elimination is not enhanced by OXC. Moreover, OXC seems to have little effect on cytochrome P-450. Aldo-keto reductases and glucuronyltransferases are in general less sensitive to induction and inhibition than are P-450 dependent enzymes. On the whole, OXC possesses very little potential for metabolic drug interactions, and thus differs favourably from other anti-epileptic drugs.
Pharmacokinetics of Anti-Epileptic Drugs and their Clinical Significance
Authors: Johannessen Svein I.
Published: March 2014

The serum concentration achieved and maintained following the administration of a fixed drug dosage is a direct consequence of the interactions of a wide variety of interrelated processes, including drug absorption, distribution, metabolism, and excretion, and the physiological status of the patient. These interrelationships are reviewed with specific reference to the major anti-epileptic drugs, phenobarbitone, phenytoin, sodium valproate, and carbamazepine, as well as a new first-line antiepileptic, oxcarbazepine. Both older drugs, such as phenobarbitone and phenytoin, and newer drugs, such as carbamazepine (CBZ) and sodium valproate, have been studied extensively over the past years giving valuable information for drug treatment. An important feature of oxcarbazepine (OXC) , which was developed through minimal changes in the structure of CBZ in order to improve on the tolerability of CBZ without sacrificing efficacy, is that its metabolites do not include the 11-epoxide which has been implicated in the side-effects of CBZ. In man, OXC is metabolized to a monohydroxy derivative which has independent anti-epileptic properties. OXC seems to lack several disadavantageous pharmacokinetic properties common to other major anti-epileptic drugs. OXC does not influence its own metabolism after repeated administration, in contrast to the auto-induction displayed by CBZ. The metabolism of OXC is not influenced by anti-epileptic co-medication and does not influence the kinetics of other anti-epileptic drugs – or if it does, then to a lesser extent than CBZ.
Association between Hlaantigens and Progression of HIV Infection in Greek Haemophiliacs
Authors: Papasteriades Chr. , Economidou J. , Pappas H. , Psarra K. , Kapsimali V. , Karafoulidou K. , Mandalaki T. , Papaevangelou G.
Published: March 2014

The frequencies of HLA antigens in 33 HIV seronegative and in 88 HIV seropositive haemophiliacs, who have been followed for at least 6 years since seroconversion or first HIV positive test. were evaluated in relation to disease susceptibility and disease progression. A high frequency of HLA‐A2 and ‐DR2 antigens and a low frequency of HLA‐A9 were found to characterize HIV seropositive patients (p<0.05). Progressors to symptomatic CDC stage IV had a higher frequency of HLA‐A9 (p<0.01) and DR3. Rapid decline of CD4+ T cells in these patients was associated with HLA‐A9, ‐DR I and DR3. Our data suggest that HLA antigens may contribute to susceptibility to HIV infection and disease progression in Greek haemophiliacs.
TaqI Digestion of PCR Product Increases the Informativity of St14 Vntr for the Diagnosis of Hemophilia A
Authors: Saksova L. , Gecz J. , Kadasl L. , Ferak V.
Published: March 2014

Recently, a pair of PCR primers have been described that make it possible to amplify a highly polymorphic VNTR locus DX552 (St14). PCR products range in size from approximately 650 to 3000 bp. Ninety X chromosomes from unrelated Caucasian subjects were investigated. Digestion of the PCR products with TaQI revealed the presence of a polymorphic TaQI restriction site within the product 200 bp from the end. This restriction site is present on 60% and absent on 40% of all alleles, but the absence is confined solely to the alleles 1690 bp (39%) and 2100 bp (1%). Thus, there is a strong allelic association between the most frequent 1690 bp allele and the absence of the TaQI restriction site. Determination of this polymorphisms within the St 14 VNTR region increases the expected heterozygosity at the DXS52 locus from 72% to 80%. This increases the fraction of hemophilia A families where this marker is informative for indirect prenatal diagnosis and carrier identification.
A Note on the Solutions of Some Nonlinear Equations Arising in Third-Grade Fluid Flows: An Exact Approach
Authors: Aziz Taha , Mahomed F. M.
Published: March 2014

In this communication, we utilize some basic symmetry reductions to transform the governing nonlinear partial differential equations arising in the study of third-grade fluid flows into ordinary differential equations. We obtain some simple closed-form steady-state solutions of these reduced equations. Our solutions are valid for the whole domain [0,∞) and also satisfy the physical boundary conditions. We also present the numerical solutions for some of the underlying equations. The graphs corresponding to the essential physical parameters of the flow are presented and discussed.
Fluoxetine Dose and Administration Method Differentially Affect Hippocampal Plasticity in Adult Female Rats
Authors: Pawluski Jodi L. , van Donkelaar Eva , Abrams Zipporah , Houbart Virginie , Fillet Marianne , Steinbusch Harry W. M. , Charlier Thierry D.
Published: March 2014

Selective serotonin reuptake inhibitor medications are one of the most common treatments for mood disorders. In humans, these medications are taken orally, usually once per day. Unfortunately, administration of antidepressant medications in rodent models is often through injection, oral gavage, or minipump implant, all relatively stressful procedures. The aim of the present study was to investigate how administration of the commonly used SSRI, fluoxetine, via a wafer cookie, compares to fluoxetine administration using an osmotic minipump, with regards to serum drug levels and hippocampal plasticity. For this experiment, adult female Sprague-Dawley rats were divided over the two administration methods: (1) cookie and (2) osmotic minipump and three fluoxetine treatment doses: 0, 5, or 10 mg/kg/day. Results show that a fluoxetine dose of 5 mg/kg/day, but not 10 mg/kg/day, results in comparable serum levels of fluoxetine and its active metabolite norfluoxetine between the two administration methods. Furthermore, minipump administration of fluoxetine resulted in higher levels of cell proliferation in the granule cell layer (GCL) at a 5 mg dose compared to a 10 mg dose. Synaptophysin expression in the GCL, but not CA3, was significantly lower after fluoxetine treatment, regardless of administration method. These data suggest that the administration method and dose of fluoxetine can differentially affect hippocampal plasticity in the adult female rat.
Identifying Potential Clinical Syndromes of Hepatocellular Carcinoma Using PSO-Based Hierarchical Feature Selection Algorithm
Authors: Ji Zhiwei , Wang Bing
Published: March 2014

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. Clinical symptoms attributable to HCC are usually absent, thus often miss the best therapeutic opportunities. Traditional Chinese Medicine (TCM) plays an active role in diagnosis and treatment of HCC. In this paper, we proposed a particle swarm optimization-based hierarchical feature selection (PSOHFS) model to infer potential syndromes for diagnosis of HCC. Firstly, the hierarchical feature representation is developed by a three-layer tree. The clinical symptoms and positive score of patient are leaf nodes and root in the tree, respectively, while each syndrome feature on the middle layer is extracted from a group of symptoms. Secondly, an improved PSO-based algorithm is applied in a new reduced feature space to search an optimal syndrome subset. Based on the result of feature selection, the causal relationships of symptoms and syndromes are inferred via Bayesian networks. In our experiment, 147 symptoms were aggregated into 27 groups and 27 syndrome features were extracted. The proposed approach discovered 24 syndromes which obviously improved the diagnosis accuracy. Finally, the Bayesian approach was applied to represent the causal relationships both at symptom and syndrome levels. The results show that our computational model can facilitate the clinical diagnosis of HCC.
Antioxidant Capacity and Proanthocyanidin Composition of the Bark of Metasequoia glyptostroboides
Authors: Chen Fengyang , Zhang Lin , Zong Shuling , Xu Shifang , Li Xiaoyu , Ye Yiping
Published: March 2014

Metasequoia glyptostroboides Hu et Cheng is the only living species in the genus Metasequoia Miki ex Hu et Cheng (Taxodiaceae), which is well known as a “living fossil” species. In the Chinese folk medicine, the leaves and bark of M. glyptostroboides are used as antimicrobic, analgesic, and anti‐inflammatory drug for dermatic diseases. This study is the first to report the free radical scavenging capacity, antioxidant activity, and proanthocyanidin composition of the bark of M. glyptostroboides. We observed total of six extracts and fractions, which were easily obtained by water‐ethanol extraction and followed by a further separation with D101 resin column chromatography, had significant DPPH radical, superoxide anion radical, and hydroxyl radical scavenging capacity, total antioxidative capacity (T‐AOC), lipid peroxidation inhibitory activity, and metal ions chelating capacity. The fraction MGEB, which was obtained by 60% ethanol extraction and followed by a further separation with D101 resin column chromatograph, possessed the highest proanthocyanidin content and the highest free radical scavenging and antioxidant activities. Furthermore, MGEB could significantly protect against CCl4 induced acute liver injury through inhibition of oxidative stress in mice. In addition, ten proanthocyanidins were isolated from MGEB, and six of them were firstly reported from this plant.
Association of Single Nucleotide Polymorphisms in Estrogen Receptor Alpha Gene with Susceptibility to Knee Osteoarthritis: A Case-Control Study in a Chinese Han Population
Authors: Dai Xiaoyu , Wang Chao , Dai Jin , Shi Dongquan , Xu Zhihong , Chen Dongyang , Teng Huajian , Jiang Qing
Published: March 2014

Osteoarthritis (OA) is the most prevalent form of arthritis and its multifactorial nature has been increasingly recognized. Genetic factors play an important role in OA etiology and estrogen receptor alpha (ESR1) gene polymorphisms may be involved. This study tried to explore whether the ESR1 gene single nucleotide polymorphisms (SNPs) were associated with primary knee OA in the Chinese Han population. Two SNPs, rs2234693 and rs9340799, were genotyped in 469 cases and 522 controls. Rs2234693 was associated with knee OA in the dominant genetic model (TT + TC versus CC)(P=0.025)and a higher T allele frequency existed(P=0.047)among females. The combined genotype (TT + TC)(P=0.025)and T allele(P=0.016)were related with mild knee OA only. For rs9340799, A allele was associated with knee OA in all subjects(P=0.031)and females(P=0.046). Statistical differences were detected in the dominant genetic model (AA + AG versus GG) among females(P=0.030). The combined genotype (AA + AG)(P=0.036)and A allele(P=0.039)were merely correlated with mild knee OA. ESR1 gene is considerably associated with knee OA etiology in the Chinese Han population.
Protective Effect of Danhong Injection on Acute Hepatic Failure Induced by Lipopolysaccharide and D‐Galactosamine in Mice
Authors: Wang Ying , Gao Li-Na , Cui Yuan-Lu , Jiang Heng-Li
Published: March 2014

Acute hepatic failure (AHF), which leads to an extremely high mortality rate, has become the focus of attention in clinic. In this study, Danhong injection (DHI) was investigated to evaluate the preventive and protective effect on AHF induced by lipopolysaccharide (LPS) and D‐galactosamine (GalN) in mice. For AHF induction, ICR mice were intraperitoneally injected with D‐GalN (700 mg/kg) and LPS (20 μg/kg). DHI was administrated twice, at 12 and 1 h, respectively, before D‐GalN/LPS injection. After stimulation with D‐GalN/LPS for 1 and 6 h, serum and livers were collected for analysis. We found that mice administrated with DHI displayed a higher survival rate, lower serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil), glutathione S‐transferase (GST), and tumor necrosis factor (TNF)‐α. DHI inhibited the elevations of hepatic lipid peroxidation (malondialdehyde), caspase‐8 activity, and mRNA expression levels of inflammatory cytokines (interleukin‐1β and interleukin‐6) increased by D‐GalN/LPS in the liver. Furthermore, liver histopathological analysis indicated that the DHI group showed markedly fewer apoptotic (TUNEL positive) cells and less pathological changes than those in the AHF model group. These results provide a novel insight into the pharmacological actions of DHI as a potential candidate for treating AHF.
Compact Dual-Band Dipole Antenna with Asymmetric Arms for WLAN Applications
Authors: Chiu Chung-Hsiu , Lin Chun-Cheng , Huang Chih-Yu , Lin Tsai-Ku
Published: March 2014

A dual-band dipole antenna that consists of a horn- and a C-shaped metallic arm is presented. Depending on the asymmetric arms, the antenna provides two −10 dB impedance bandwidths of 225 MHz (about 9.2% at 2.45 GHz) and 1190 MHz (about 21.6% at 5.5 GHz), respectively. This feature enables it to cover the required bandwidths for wireless local area network (WLAN) operation at the 2.4 GHz band and 5.2/5.8 GHz bands for IEEE 802.11 a/b/g standards. More importantly, the compact size (7 mm × 24 mm) and good radiating performance of the antenna are profitable to be integrated with wireless communication devices on restricted RF-elements spaces.
Total Positivity of the Cubic Trigonometric Bézier Basis
Authors: Han Xuli , Zhu Yuanpeng
Published: March 2014

Within the general framework of Quasi Extended Chebyshev space, we prove that the cubic trigonometric Bézier basis with two shape parametersλandμgiven in Han et al. (2009) forms an optimal normalized totally positive basis forλ,μ∈(-2,1]. Moreover, we show that forλ=-2orμ=-2the basis is not suited for curve design from the blossom point of view. In order to compute the corresponding cubic trigonometric Bézier curves stably and efficiently, we also develop a new corner cutting algorithm.
The Generalized Bisymmetric (Bi-Skew-Symmetric) Solutions of a Class of Matrix Equations and Its Least Squares Problem
Authors: Ke Yifen , Ma Changfeng
Published: March 2014

The solvability conditions and the general expression of the generalized bisymmetric and bi-skew-symmetric solutions of a class of matrix equations(AX=B,XC=D)are established, respectively. If the solvability conditions are not satisfied, the generalized bisymmetric and bi-skew-symmetric least squares solutions of the matrix equations are considered. In addition, two algorithms are provided to compute the generalized bisymmetric and bi-skew-symmetric least squares solutions. Numerical experiments illustrate that the results are reasonable.
Identification of LTI Time‐Delay Systems with Missing Output Data Using GEM Algorithm
Authors: Yang Xianqiang , Karimi Hamid Reza
Published: March 2014

This paper considers the parameter estimation for linear time‐invariant (LTI) systems in an input‐output setting with output error (OE) time‐delay model structure. The problem of missing data is commonly experienced in industry due to irregular sampling, sensor failure, data deletion in data preprocessing, network transmission fault, and so forth; to deal with the identification of LTI systems with time‐delay in incomplete‐data problem, the generalized expectation‐maximization (GEM) algorithm is adopted to estimate the model parameters and the time‐delay simultaneously. Numerical examples are provided to demonstrate the effectiveness of the proposed method.
New Enlightenment of Skin Cancer Chemoprevention through Phytochemicals:In VitroandIn VivoStudies and the Underlying Mechanisms
Authors: Singh Madhulika , Suman Shankar , Shukla Yogeshwer
Published: March 2014

Skin cancer is still a major cause of morbidity and mortality worldwide. Skin overexposure to ultraviolet irradiations, chemicals, and several viruses has a capability to cause severe skin-related disorders including immunosuppression and skin cancer. These factors act in sequence at various steps of skin carcinogenesis via initiation, promotion, and/or progression. These days cancer chemoprevention is recognized as the most hopeful and novel approach to prevent, inhibit, or reverse the processes of carcinogenesis by intervention with natural products. Phytochemicals have antioxidant, antimutagenic, anticarcinogenic, and carcinogen detoxification capabilities thereby considered as efficient chemopreventive agents. Considerable efforts have been done to identify the phytochemicals which may possibly act on one or several molecular targets that modulate cellular processes such as inflammation, immunity, cell cycle progression, and apoptosis. Till date several phytochemicals in the light of chemoprevention have been studied by using suitable skin carcinogenicin vitroandin vivomodels and proven as beneficial for prevention of skin cancer. This revision presents a comprehensive knowledge and the main molecular mechanisms of actions of various phytochemicals in the chemoprevention of skin cancer.
Statistical Prediction of Summer Rainfall and Vegetation in the Ethiopian Highlands
Authors: Jury Mark R.
Published: March 2014

Year-to-year fluctuations of Ethiopia climate are investigated to develop statistical predictions at one-season lead time. Satellite vegetation data from NASA and rainfall from ARC2 are the basis for analysis. The “target” seasons are May–July and August–October, while “predictors” are December–February and March–May, respectively. Global fields of surface temperature, sea level air pressure, and upper and lower level zonal winds are employed in point-to-field correlations. After step-wise multivariate regression, the leading predictors are: surface temperature across Europe (cold-favourable), 850 mb zonal winds over the tropical Atlantic (easterly-favourable), and surface temperature in the tropical Indian Ocean (cold-favourable). Predictive algorithms for early and late rainfall exhibit a consistentr2fit of ~0.50, while those for vegetation reach ~0.65 in late summer, indicating that fluctuations in food resources could be forewarned.
Attainability Analysis for Entry Vehicles Based on Differential Evolution
Authors: Chang Songtao , Wang Yongji , Liu Lei , Wei Xing
Published: March 2014

Attainable region provides crucial information on mission planning of entry vehicles. In order to obtain it, a series of
nonlinear optimal control problems which have similar formulations are needed to be solved. However, it is difficult
to compute due to severe nonlinearity of the dynamics and various constraints. In this paper, a novel method is
established to generate the attainable region at the end of the entry phase. It utilizes the parallel feature of differential
evolution (DE) and the high accuracy of Chebyshev polynomial interpolation. By using the Chebyshev polynomial
interpolation, the original problem is transformed to several nonlinear programming problems to facilitate employing
DE. Each individual in DE’s population represents a candidate point on the boundary of the attainable region. In order
to lead the population to the boundary simultaneously, a scheme is devised by exploiting the parallel feature of DE.
Different from conventional methods which generate one point of the boundary in each run, our proposed method
generates one side of the boundary of the attainable region. A scenario is presented to evaluate the designed method
and some analyses are conducted to evaluate the influence of the vehicle’s design parameters on the attainable region.
An Improved Mathematical Model for Computing Power Output of Solar Photovoltaic Modules
Authors: Jakhrani Abdul Qayoom , Samo Saleem Raza , Kamboh Shakeel Ahmed , Labadin Jane , Rigit Andrew Ragai Henry
Published: March 2014

It is difficult to determine the input parameters values for equivalent circuit models of photovoltaic modules through analytical methods. Thus, the previous researchers preferred to use numerical methods. Since, the numerical methods are time consuming and need long term time series data which is not available in most developing countries, an improved mathematical model was formulated by combination of analytical and numerical methods to overcome the limitations of existing methods. The values of required model input parameters were computed analytically. The expression for output current of photovoltaic module was determined explicitly by Lambert W function and voltage was determined numerically by Newton-Raphson method. Moreover, the algebraic equations were derived for the shape factor which involves the ideality factor and the series resistance of a single diode photovoltaic module power output model. The formulated model results were validated with rated power output of a photovoltaic module provided by manufacturers using local meteorological data, which gave ±2% error. It was found that the proposed model is more practical in terms of precise estimations of photovoltaic module power output for any required location and number of variables used.