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This paper, along with an earlier published paper as Part 1, provides a comprehensive review of the state of the art of high-power converters (above 1 MW) for adjustable-speed ac drives. In this highly active area, different converter topologies have been developed for various drive applications in the industry. Due to its extensive coverage, the subject is divided into two parts: multilevel voltage source and current source converter topologies. This paper is focused on the second part and covers the current source converter technologies, including pulsewidth-modulated current-source inverters (CSIs) and load-commutated inverters. In addition, this paper also addresses the present status of the direct converter, which is also known as cycloconverter (CCV). This paper focuses on the latest CSI and CCV technologies and an overview of the commonly used modulation schemes. It also provides the latest technological advances and future trends in CSI- and CCV-fed large drives. This paper serves as a useful reference for academic researchers and practicing engineers in the field of power converters and adjustable-speed drives. [ABSTRACT FROM AUTHOR]

A novel dc voltage detection technique, referred to as single multiple-voltage (SMV) detector, is developed to obtain dc capacitor voltages in the cascaded H-bridge (CHB) multilevel inverter-based static synchronous compensator (STATCOM). Based on the proposed SMV algorithm, the number of voltage sensors is substantially reduced. Only three voltage sensors are required to obtain dc capacitor voltages from the inverter output voltage. The paper also presents a new dc voltage balance control method that combines the phase shifting technique and sinusoidal pulsewidth modulation (SPWM) strategy for the control of H-bridge dc capacitor voltages. The performance of CHB inverter-based STATCOM system, the accuracy of the developed SMV detector and the effectiveness of the proposed dc voltage balance control are verified by simulations in Simulink environment and experiments based on the dSPACE prototype system. [ABSTRACT FROM AUTHOR]

An efficient Delaunay-Voronoi modeling of the power-ground planes suitable directly for SPICE compatibity is proposed to deal with the ground bounce noise and decoupling capacitors placement problems for the high-speed digital system designs. The model consists of virtual ports and triangular meshes with the lumped circuit elements, in which all the element values can be related to the mesh geometry shape by the analogy between the circuit equations and Maxwell's equations. Since the analogy fails to apply due to the singular fields near the input/output pins, the via effect of driving and sensing ports is not negligible and an analytical expression from the Hankel function is thus presented for the correction term. A simple rule has been investigated for the model with minimum lumped circuit elements to accurately represent the power-ground planes over the frequency range of interests. The full-wave simulation and measurement results verify the good correlations with the proposed models for the impedance responses of regular and defective plane shapes. [ABSTRACT FROM AUTHOR]

Two types of β-enaminoketone derivatives of 3-(2-oxo-2-arylethylidene)-3,4-dihydro-1H-quinoxalin-2-ones and 3-(2-oxo-2-arylethylidene)-3,4-dihydro-benzo[1,4]oxazin-2- ones were effectively and conveniently prepared in good to excellent yields under solvent-free conditions via the catalysis of sulfamic acid in the corresponding condensations of o-phenylenediamine and o-aminophenol with ethyl 2,4-dioxo-4-arylbutyrate respectively. The compounds were confirmed by IR, 1H NMR, and 13C NMR, and a representative was further determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Space vector pulsewidth modulation (PWM) schemes for the active front end of a high-power drive normally produce low-order and suborder harmonics due to the low switching frequency and the drifting of synchronization between the PWM waveform and the rectifier input frequency. To provide a synchronized PWM and achieve the best harmonic performance, different space vector sequences suitable for a current-source converter are investigated in this paper. Details on how to achieve the waveform symmetries with a minimum switching frequency for each sequence are discussed. A thorough comparison of the harmonic performance of different space vector sequences is carried out. An optimum space vector modulation method by switching between two best sequences is proposed to achieve the best line-current total harmonic distortion with reduced switching losses. In addition, two synchronization methods, namely a PWM frame regulation method and a direct digital phase-locked loop synchronization method, are proposed. Both methods are equally effective in providing tight synchronization of the PWM waveform with the rectifier input frequency. The work has been verified in simulation and experiment. [ABSTRACT FROM AUTHOR]

The article reports on results of a study of antifeedants against the insect species, Locusta migratoria from the Japanese cedar, Cryptomeria japonica II. A description of the experimental set-up and measurement methods is presented. The study showed that each compound separately showed weak activity. However, they showed intense activity against Locusta migratoria when they were combined.

To study the Schneider’s projection problem, Lutwak, Yang and Zhang recently introduced a new affine invariant functional U( P) for convex polytopes in R n . In the paper, we obtain the analytic expression of the affine-invariant U( P) defined on a specific subclass of origin-symmetric convex polytopes in R n and give an application of U( P) to the L p -Minkowski problem. [ABSTRACT FROM AUTHOR]

Background: Current analgesics have drawbacks such as delays in acquisition, lag-times for effect, and side effects. We recently presented a preliminary report of a new analgesic method involving a two-minute sciatic nerve press, which resulted in immediate short-term relief of pain associated with dental and renal diseases. The present study investigated whether this technique was effective for pain associated with other disease types, and whether the relief was effective for up to one hour. Methods: This randomized, placebo-controlled, parallel-group trial was conducted in four hospitals in Anhui Province, China. Patients with pain were sequentially recruited by participating physicians during clinic visits, and 135 patients aged 15-80 years were enrolled. Dental disease patients included those with acute pulpitis and periapical abscesses. Renal disease patients included those with kidney infections and/or stones. Tumor patients included those with nose, breast, stomach and liver cancers, while Emergency Room patients had various pathologies. Patients were randomly assigned to receive a "sciatic nerve press" in which pressure was applied simultaneously to the sciatic nerves at the back of both thighs, or a "placebo press" in which pressure was applied to a parallel region on the front of the thighs. Each fist applied a pressure of 11-20 kg for 2 minutes. Patients rated their level of pain before and after the procedure. Results: The "sciatic nerve press" produced immediate relief of pain in all patient groups. Emergency patients reported a 43.5% reduction in pain (p < 0.001). Significant pain relief for dental, renal and tumor patients lasted for 60 minutes (p < 0.001). The peak pain relief occurred at the 10-20th minutes, and the relief decreased 47% by the 60th minutes. Conclusion: Two minutes of pressure on both sciatic nerves produced immediate significant short-term conduction analgesia. This technique is a convenient, safe and powerful method for the short-term treatment of clinical pain associated with a diverse range of pathologies. Trial registration: Current Controlled Trials ACTRN012606000439549 [ABSTRACT FROM AUTHOR]

The article presents research on the global existence and extinction of weak solutions to a class of semiconductor equations with fast diffusion terms. It shows the existence result for general nonlinear diffusivities for the Dirichlet-Neumann mixed boundary value problem. It investigates the extinction phenomenon of weak solutions for homogeneous Dirichlet boundary problem. The p-Laplacian (Lp)-integral model estimate method a crucial lemma on differential inequality were employed to prove the result of sufficient conditions on the extinction and decay estimates of solutions. It notes that the technique has been successfully applied to the porous medium equation.

Abstract: Three dimensional Born and Kirchhoff inverse scattering methods are modified to convenient forms for a cylindrical specimen that includes three dimensional defect. One aluminum cylinder with flaw model is prepared and ultrasonic measurements are carried out. The measurement area in the modified methods is restricted in the plane perpendicular to the axis of cylindrical specimen. That is to say that the methods are modified to convenient form to use measured waveforms in the x 1–x 2 plane. The measured wave data are fed into the inversion method and cross-sectional images are obtained. Then, three dimensional shape reconstruction of flaw model in aluminum specimen is performed by piling up the cross-sectional images. [Copyright &y& Elsevier]

This paper presents a novel switching sequence design for the space-vector modulation of high-power multi- level converters. The switching sequences are optimized for the improvement of harmonic spectrum and the minimization of device switching frequency. Compared to other commonly used switching sequences, the output spectrum of the proposed design shows higher inverter equivalent switching frequency. Meanwhile, the device switching frequency is reduced by using a flexible switching pattern. The proposed switching sequence has been simulated and experimentally tested on a 5-level neutral point clamped H-bridge based inverter. The results from both simulations and experiments consistently verify the above-mentioned features. [ABSTRACT FROM AUTHOR]

Objectives: Hepatitis C virus (HCV) F protein is a newly identified protein encoded by an alternative open reading frame that +1 overlaps core-encoding gene. It has been found that regulation of c-myc and p53 genes by HCV core protein is involved in liver cancer genesis. We wondered whether HCV F protein exerts similar or adverse regulatory effects on the transcription of c-myc and p53 genes. Methods: HCV F gene-containing, plasmid pcDNA3.1-F and HCV core gene-containing pcDNA3.1-C were constructed and transiently transfected into HepG2 cells. Real-time quantitative PCR or Western blotting was used to determine the changes at transcription or translation levels of c-myc and p53 genes. Results: The transcription level of c-myc was much higher in pcDNA3.1-F transfected cells than those without plasmid transfected. Whereas the level of p53 transcription in pcDNA3.1-F transfected cells was lower than those in the parental cells. Moreover, levels of c-myc expression were up-regulated and those of p53 expression were down-regulated by HCV F protein. Conclusions: HCV F protein is of regulatory properties in cellular oncogene c-myc and anti-oncogene p53, which may be implicated in the formation of hepatocellular carcinoma. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We report the direct delivery and assembly of negatively charged gold colloidal particles atop positively charged amino-terminated silicon oxide surfaces using a nanofountain atomic force microscopy probe. The experimental results and fluid simulations indicate that the flow of nanoparticles is confined to the core tip region of the probe. This leads to the assembly of high-resolution submicron patterns (200 nm) on the substrate with feature sizes dependent on the tip−substrate contact time. A diffusion mechanism for the patterning is proposed and discussed. [ABSTRACT FROM AUTHOR]

An inductor-capacitor (LC) filter is normally required at the input of a pulse-width modulation (PWM) current source rectifier (CSR), to assist in the commutation of switching devices and to mitigate line current harmonics. To dampen the LC resonance introduced by the input filter, an effective damping method is proposed in this paper by using a hybrid combination of a virtual harmonic resistive damper and a three-step control signal compensator. The virtual harmonic resistor, which is immune to system parameter variations, can dampen the LC resonance caused by an external disturbance or control command changes without affecting the fundamental power flow. But the high-pass filter used for fundamental component elimination leads to poor dynamics. Therefore, a proposed three-step compensator is inserted into the DC current closed-loop control path which can effectively eliminate the resonance within the control loop by shaping the modulation signal. Compared to the two-step Posicast controller, the proposed three-step compensator has significant implementation advantages in medium voltage CSRs, where a low switching frequency is needed. By using a hybrid combination approach, dynamics of the virtual harmonic resistor can be improved with the transient overshoot mitigated by the three-step compensator. At the same time, the parameter sensitivity of the three-step compensator can be reduced, as any residual resonant oscillations can be dampened by the virtual resistor. Simulation and experimental results are provided to verify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: An elastodynamic solution for the stress wave propagation in spherical curved plates composed of functionally graded materials (FGM) is presented. Properties of materials are assumed to vary in the direction of the thickness according to a known radial variation law (gradient field). The formulation is based on the linear three-dimensional elasticity. The Legendre orthogonal polynomial series expansion approach is used for determining the guided waves dispersion curves in functionally graded spherical curved plates. Our results from a homogeneous anisotropic spherical curved plate are compared with those published earlier to confirm the accuracy and range of applicability of this polynomial approach. Guided wave dispersion curves for graded spherical curved plates with different gradient fields are calculated, and the effects of the gradient field on the characteristics of guided waves are illustrated. Finally, dispersion curves for graded spherical curved plates at different ratios of inner radius to thickness are calculated to discover the influences of that ratio on the wave characteristics. [Copyright &y& Elsevier]

A stable property continues to hold in an execution once it becomes true. Detecting arbitrary stable properties efficiently in distributed executions is still an open problem. The known algorithms for detecting arbitrary stable properties and snapshot algorithms used to detect such stable properties suffer from drawbacks such as the following: They incur the overhead of a large number of messages per global snapshot, or alter application message headers, or use inhibition, or use the execution history, or assume a strong property such as causal delivery of messages in the system. We solve the problem of detecting an arbitrary stable property efficiently under the following assumptions: P1) The application messages should not be modified, not even by timestamps or message coloring. P2) No inhibition is allowed. P3) The algorithm should not use the message history. P4) Any process can initiate the algorithm, This paper proposes a family of nonintrusive algorithms requiring 6(n - 1) control messages, where, is the number of processes. A three-phase strategy of uncoordinated observation of local states is used to give a consistent snapshot from which any stable property can be detected, A key feature of our algorithms is that they do not rely on the processes continually and pessimistically reporting their activity. Only the relevant activity that occurs in the thin slice during the algorithm execution needs to be examined. [ABSTRACT FROM AUTHOR]

Abstract: In ultrasonic nondestructive inspection of large-diameter pipes and curved plate, longitudinal cracks are detected more efficiently by using guided circumferential waves. In the present, the study of guided circumferential waves and their application in detecting longitudinal defect were relative adequate when pipe material is isotropic. Based on linear three-dimensional elasticity, an orthogonal polynomial series expansions approach is used for determining the guided circumferential waves dispersion curves in homogeneous infinitely long orthotropic hollow cylinders. Results are compared with those published earlier and with the finite element simulation to check up the accuracy and range of applicability of this polynomial approach. Through the analysis of the displacements distributions and finite element simulation, the mode conversion of guided circumferential waves by end-reflection in cylindrical curved plate is discovered. [Copyright &y& Elsevier]

Background: The small intestine is highly sensitive to ischaemia-reperfusion (I/R) induced injury which is associated with high morbidity and mortality. Apoptosis, or programmed cell death, is a major mode of cell death occurring during I/R induced injury. However, the mechanisms by which I/R cause apoptosis in the small intestine are poorly understood, p53 upregulated modulator of apoptosis (PUMA) is a p53 downstream target and a member of the BH3-only group of Bcl-2 family proteins. It has been shown that PUMA plays an essential role in apoptosis induced by a variety of stimuli in different tissues through a mitochondrial pathway. Aims: The role of PUMA in I/R induced injury and apoptosis in the small intestine was investigated. The mechanisms by which PUMA is regulated in I/R induced intestinal apoptosis were also studied. Methods: Ischaemia was induced by superior mesenteric artery occlusion in the mouse small intestine. Induction of PUMA in response to ischaemia alone, or ischaemia followed by reperfusion (I/R), was examined. I/R induced intestinal apoptosis and injury were compared between PUMA knockout and wild-type mice. The mechanisms of I/R induced and PUMA mediated apoptosis were investigated through analysis of caspase activation, cytosolic release of mitochondrial cytochrome c and alterations of the proapoptotic Bcl-2 family proteins Bax and Bak. To determine whether PUMA is induced by reactive oxygen species and/or reactive nitrogen species generated by I/R, superoxide dismutase (SOD) and N-nitro-ʟ-arginine methyl ester (L-NAME) were used to treat animals before I/R. To determine whether p53 is involved in regulating PUMA during I/R induced apoptosis, PUMA induction and apoptosis in response to I/R were examined in p53 knockout mice. Results: PUMA was markedly induced following I/R in the mucosa of the mouse small intestine. I/R induced intestinal apoptosis was significantly attenuated in PUMA knockout mice compared with that in wild-type mice. I/R induced caspase 3 activation, cytochrome c release, Bax mitochondrial translocation and Bak multimerisation were also inhibited in PUMA knockout mice. SOD or L-NAME significantly blunted I/R induced PUMA expression and apoptosis. Furthermore, I/R induced PUMA expression and apoptosis in the small intestine were not affected in the p53 knockout mice. Conclusions: Our data demonstrated that PUMA is activated by oxidative stress in response to I/R to promote p53 independent apoptosis in the small intestine through the mitochondrial pathway. Inhibition of PUMA is potentially useful for protecting against I/R induced intestinal injury and apoptosis. [ABSTRACT FROM AUTHOR]

The article discusses the identification of the antifeedants in Cryptomeria japonica against Locusta migratoria L. in a multi-component system requiring multiple components to exhibit its activity. The compounds, (1S,6R)-2,7(14),10-bisabolatrien-1-ol-4-one and (+)-7(14),10-bisaboladien-1-ol-4-one, strongly inhibited the feeding of Locusta migratoria only when they were combined, but each compound alone did not show any activity.

Background: Despite much research, an immediately available, instantly effective and harmless pain relief technique has not been discovered. This study describes a new manipulation: a "2-minute sciatic nerve press", for rapid short-term relief of pain brought on by various dental and renal diseases. Methods: This randomized, single-blind, placebo-controlled trial ran in three hospitals in Anhui Province, China, with an enrollment of 66 out of 111 solicited patients aged 16 to 74 years. Patients were recruited sequentially, by specific participating physicians at their clinic visits to three independent hospitals. The diseases in enrolled dental patients included dental caries, periodontal diseases and dental trauma. Renal diseases in recruits included kidney infections, stones and some other conditions. Patients were randomly assigned to receive the "2-minute sciatic nerve press" or the "placebo press". For the "2-minute sciatic nerve press", pressure was applied simultaneously to the sciatic nerves at the back of the thighs, using the fists while patients lay prone. For the "placebo press", pressure was applied simultaneously to a parallel spot on the front of the thighs, using the fists while patients lay supine. Each fist applied a pressure of 11 to 20 kg for 2 minutes, after which, patients arose to rate pain. Results: The "2-minute sciatic nerve press" produced greater pain relief than the "placebo press". Within the first 10 minutes after sciatic pressure, immediate pain relief ratings averaged 66.4% (p < 0.001) for the dental patients, versus pain relief of 20% for the placebo press, and, 52.2% (p < 0.01) for the renal patients, versus relief of 14% for the placebo press, in median. The method worked excellently for dental caries and periodontal diseases, but poorly for dental trauma. Forty percent of renal patients with renal colic did not report any pain relief after the treatment. Conclusion: Two minutes of pressure on both sciatic nerves can produce immediate significant conduction analgesia, providing a convenient, safe and powerful way to overcome clinical pain brought on by dental diseases and renal diseases for short term purposes. [ABSTRACT FROM AUTHOR]

Objective To investigate the value of in vivo proton magnetic resonance spectroscopy (MRS) in the assessment of hepatocellular carcinoma (HCC) and monitor its metabolic change shortly after transcatheter arterial chemoembolization (TACE). Methods In this prospective study, 28 consecutive patients with large HCC (⩾3 cm in diameter) confirmed by fine needle aspiration biopsy were recruited. The 1H MRS of all hepatic lesions and some uninvolved liver parenchyma were performed with 1.51 whole body MR scanner. Among them, 15 cases were evaluated again about one week after TACE. The main metabolites such as choline and lipid before and after interventional therapy were measured to assess the early response of the tumor. Results The technical success rate of 1H MRS in liver was high (33/41, 80% ) , closely related to breath motion, location of lesion, and size of voxel. In spectra, the choline compound peak of HCC elevated compared with uninvolved liver parenchyma. After TACE, both the amplitude and the area of choline resonance peak significantly descended (choline-to-lipid ratios from 0. 352 ± 0. 080 to 0. 167 ± 0. 030, P = 0. 026; from 0. 205 ± 0. 060 to 0. 070 ± 0. 020, P =0. 042, respectively); yet lipid resonance peak ascended. Conclusions In vivo `H MRS is technically feasible for the evaluation of large focal hepatic lesions, however, the reproducibility and stability are not as good as routine MR scan. 1H MRS can monitor the early stage metabolic changes of HCC after TACE but limitation like quantification still exists. [ABSTRACT FROM AUTHOR]

A multivariable self-tuning adaptive control scheme used to enhance power system stability in a multimachine environment is presented. The controller is implemented locally for individual generators with supplementary stabilizing signals through the AVR and governor. A discrete multivariable state space model is developed to represent the generator. The recursive subspace identification method based on the projection approximation subspace tracking approach is employed to update generator model parameters online. A generalized predictive control strategy with constraints on the control signals is used. Simulations studies carried out on a five-machine power system without infinite bus show that the proposed multivariable adaptive controller is effective in damping both local and interarea mode oscillations under small as well as large disturbances. The self-coordinating ability of the adaptive controller with the existing conventional controllers is also demonstrated. [ABSTRACT FROM AUTHOR]

Objective: To screen diagnostic markers of Deficiency-Cold syndrome by gene expression profile and to establish a discriminant mathematical milliliters model for the clinical diagnosis of this syndrome based on a support vector machine (SVM). Methods: A family suffering from Deficiency-Cold syndrome is chosen for this study. This family has 5 patients with Deficiency-Cold syndrome and 10 normal members. The peripheral blood samples for these 5 patients and 5 normal members are tested by using cDNA microarray with 18,816 clones to get their differential expression genes. These genes are further explored to understand their biological functions and pathways through existing databases. A SVM model for clinical diagnosis is then developed based on these differential expression genes. Results: A total of 83 differential expression genes were identified between patients and normal members, in which 21 genes were recorded in the FATIGO database and 16 genes were related to metabolism. Eight (8) pathways were sorted out in the KEGG database, and half pathways were associated with human metabolism. A discriminant mathematical model based on a support vector machine successfully predicted a normal person and a patient with heavy Deficiency-Cold syndrome based on their gene differential expression profiles. Thus, this model may classify the Deficiency-Cold syndrome. Conclusion: This work demonstrates that the differential expression genes can be used to identify normal persons and patients with Deficiency-Cold syndrome. Deficiency-Cold syndrome is mainly associated with the metabolism-related gene regulations. In addition, the discriminant mathematical model based on a support vector machine is applicable to the clinical diagnosis for Deficiency-Cold syndrome. [ABSTRACT FROM AUTHOR]

It has been widely recognized that the dynamic-range information of an application can be exploited to reduce the datapath bitwidth of either processors or application-specific integrated circuits and, therefore, the overall circuit area, delay, and power consumption. While recent proposals of analytical dynamic-range-estimation methods have shown significant advantages over the traditional profiling-based method in terms of runtime, it is argued here that the rather simplistic treatment of input correlation and system nonlinearity may lead to significant error. In this paper, three mathematical tools, namely Karhunen-Loève expansion, polynomial chaos expansion, and independent component analysis are introduced, which enable not only the orthogonal decomposition of input random processes, but also the propagation of random processes through both linear and nonlinear systems with difficult constructs such as multiplications, divisions, and conditionals. It is shown that when applied to interesting nonlinear applications such as adaptive filters, polynomial filters, and rational filters, this method can produce complete accurate statistics of each internal variable, thereby allowing the synthesis of bitwidth with the desired tradeoff between circuit performance and signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

To exploit the novel size-dependent mechanical properties of nanowires, it is necessary for one to develop strategies to control the strength and toughness of these materials. Here, we report on the mechanical properties of silver nanowires with a unique fivefold twin structure using a lateral force atomic force microscopy (AFM) method in which wires are held in a double-clamped beam configuration. Force-displacement curves exhibit super elastic behavior followed by unexpected brittle failure without significant plastic deformation. Thermal annealing resulted in a gradual transition to weaker, more ductile materials associated with the elimination of the twinned boundary structure. These results point to the critical roles of microstructure and confinement in engineering the mechanical properties of nanoscale materials. [ABSTRACT FROM AUTHOR]

Web prefetching is based on Web caching and attempts to reduce user-perceived latency. Unlike on-demand caching, Web prefetching fetches objects and stores them in advance, hoping that the prefetched objects are likely to be accessed in the near future and such accesses would be satisfied from the caches rather than by retrieving the objects from the Web server. This paper reviews the popular prefetching algorithms based on Popularity, Good Fetch, APL characteristic, and Lifetime, and then makes the following contributions: 1) The paper proposes a family of linear-time prefetching algorithms, Objective-Greedy prefetching, wherein each algorithm greedily prefetches those Web objects that most significantly improve the performance as per the targeted metric. 2) The Hit rate-Greedy and Bandwidth-Greedy algorithms are shown to be optimal for their respective objective metrics. A linear-time optimal prefetching algorithm that maximizes the I-I/B metric as the performance measure is proposed. 3) The paper shows the results of a performance analysis via simulations, comparing the proposed algorithms with the existing algorithms in terms of the respective objectives-the hit rate, bandwidth, and the H/B metrics. The proposed prefeching algorithms are seen to provide better objective- based performance than any existing algorithms. Further, H/B-Greedy performs almost as well as H/B-Optimal [ABSTRACT FROM AUTHOR]

Purpose: To optimize the use of fresh and frozen-thawed testicular biopsy specimens from patients with azoospermia. Methods: Fifty-one patients suffering from obstructive and non-obstructive azoospermia underwent testicular sperm extraction (TESE). The specimens were divided and used for either in vitro maturation or freezing for a future intracytoplasmic sperm injection (ICSI) cycle. Results: At initial testicular sperm extraction, very few motile spermatozoa were seen. After 24 h of in vitro maturation, sperm motility increased remarkably, with a maximum motility rate seen between 48 and 72 h of culture. Motile spermatozoa were observed up to 120 h in culture. In the 22 fresh ICSI cycles, a total of 294 oocytes were injected using motile sperm and 212 oocytes demonstrated normal 2PN formation (fertilization rate, 72.1%). In 36 frozen-thawed ICSI cycles, a total of 454 oocytes were injected and 302 oocytes became 2PN (66.5%). On day 3, high quality embryos were observed in 54.2% of fresh cycles and 54.1% of frozen cycles (P > 0.05). The clinical pregnancy rate did not show a significant difference between using fresh (59%) and frozen (55.5%) testicular biopsy sperm for ICSI (P > 0.05), but the embryo implantation rates did differ significantly between fresh (29.5%) and frozen-thawed (22.2%) cycles (P < 0.05). A total of 33 healthy babies have been born from 22 women, giving birth after 58 embryo transfer attempts (38%). Conclusion: The freezing and in vitro culturing of testicular biopsy tissue is a very reliable approach for the management of testicular biopsy specimens from azoospermic patients, and offers the possibility of several treatments of IVF/ICSI from a single sample. [ABSTRACT FROM AUTHOR]

Nanowires have attracted considerable interest as nanoscale interconnects and as the active components of both electronic and electromechanical devices. Nanomechanical measurements are a challenge, but remain key to the development and processing of novel nanowire-based devices. Here, we report a general method to measure the spectrum of nanowire mechanical properties based on nanowire bending under the lateral load from an atomic force microscope tip. We find that for Au nanowires, Young's modulus is essentially independent of diameter, whereas the yield strength is largest for the smallest diameter wires, with strengths up to 100 times that of bulk materials, and substantially larger than that reported for bulk nanocrystalline metals (BNMs). In contrast to BNMs, nanowire plasticity is characterized by strain-hardening, demonstrating that dislocation motion and pile-up is still operative down to diameters of 40 nm. Possible origins for the different mechanical properties of nanowires and BNMs are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a discrete-cosine transform (DCT)-based adaptive thresholding algorithm to achieve an effective binarization of video image for binary motion estimation (BME). The BME through the full search mechanism requires extremely low hardware complexity. Experimental results show that the proposed adaptive BME attains performance close to the 8-bit resolution ME for low motion sequences with full search strategy. Compared to the well-known single-layer BME, the pro- posed adaptive algorithm shows better peak signal-to-noise ratio performance and more robustness to complex images. Moreover, the proposed algorithm has a lower computational complexity that is suitable for VLSI implementation with a smaller hardware overhead. [ABSTRACT FROM AUTHOR]

The PdCl2-catalyzed cyclocarbonylation reaction of propargylic amines with CuCl2 and benzoquinone afforded (E)-α-chloroalkylidene-β-lactams in moderate to good yields. The formation of the corresponding Z-isomers or five-membered products was not observed. The reaction of the readily available optically active prop argylic amines provides a convenient synthesis of the corresponding (E)-α-chloroalkylidene-β-lactams with high ee values. The structure and the stereochemistry of the products were established by the X-ray single-crystal diffraction study of (E)-6d and (E)-6e, which indicates that the stereoselectivity in this reaction is different from what was observed with propargylic alcohols. A rationale for this reaction was proposed. [ABSTRACT FROM AUTHOR]

A good regio- and stereoselectivity was observed for the PdCl2-catalyzed cyclocarbonylation of 2-alkynols with CuCl2 affording (Z)-α-chloroalkylidene-β-lactones. The highly optically active (Z)-α-chloroalkylidene-β-lactones could be easily prepared from the readily available optically active prop argylic alcohols. The Pd(II)-catalyzed cyclocarbonylation of 2-alkynols with CuBr2 was also studied. Although the yields of (Z)-α-bromoalkylidene-β-lactones were low, due to the relatively higher activity of the C-Br bond, the coupling reactions of (Z)-α-bromoalkylidene-β-lactones were quite smooth to afford the corresponding products in high yields. A rationale for this reaction is discussed. [ABSTRACT FROM AUTHOR]

The mid-facet of a simplex in n-dimensional Euclidean space which was introduced quite recently is an important geometric element. An analytic expression for the mid-facet area of a simplex is firstly given. In order to obtain the expression, the exterior differential method was presented. Furthermore, the properties of the mid-facets of a simplex analogous to median lines of a triangle (such as for all mid-facets of a simplex, there exists another simplex such that its edge-lengths equal to these mid-facets area respectively, and all of the mid-facets of a simplex have a common point) were proved. Finally, by applying the analytic expression, a number of inequalities which combine edgelengths, circumradius, median line, bisection area and facet area with the mid-facet area for a simplex were established. [ABSTRACT FROM AUTHOR]

GPS meteorology is a new field in GPS applications, in which precise determination of zenith delay is a key component. A strong correlation exists between the vertical displacement caused by ocean tide and the zenith delay at a given GPS station, so the effect of ocean tide on the precise determination of the zenith delay can not be neglected. We have processed and analyzed the GPS data of the Crustal Motion Observation Network of China from Day 10 to Day 40 of 2001, and the result shows that such effect varies over a range of several millimeters. For example, it is ± 7mm for the coastal station at Shanghai and ±1 mm for the inland station at Wuhan at maximum. [Copyright &y& Elsevier]

We describe the effects of the overexpression of noggin, a bone morphogenetic protein (BMP) inhibitor, on osteoblast differentiation and bone formation. Cells of the osteoblast and chondrocyte lineages, as well as bone marrow macrophages, showed intense β-gal histo- or cytostaining in adult noggin[sup+/-] mice that had a LacZ transgene inserted at the site of noggin deletion. Despite identical BMP levels, however, osteoblasts of 20-month-old C57BL/6J and 4-month-old senescence-accelerated mice (SAM-P6 mice) had noggin expression levels that were approximately fourfold higher than those of 4-month-old C57BL/6J and SAM-R1 (control) mice, respectively. U-33 preosteoblastic cells overexpressing the noggin gene showed defective maturation and, in parallel, a decreased expression of Runx-2, bone sialoprotein, osteocalcin, and RANK-L. Noggin did not inhibit the ligandless signaling and prodifferentiation action of the constitutively activated BMP receptor type 1A, ca-ALK-3. Transgenic mice overexpressing noggin in mature osteocalcin-positive osteoblasts showed dramatic decreases in bone mineral density and bone formation rates with histological evidence of decreased trabecular bone and CFU-osteoblast colonies at 4 and 8 months. Together, the results provide compelling evidence that noggin, expressed in mature osteoblasts, inhibits osteoblast differentiation and bone formation. Thus, the overproduction of noggin during biological aging may result in impaired osteoblast formation and function and hence, net bone loss. [ABSTRACT FROM AUTHOR]

Presents a preliminary empirical test of a maximum likelihood approach to using relevance date for training information retrieval parameters. Use of hypothesized distributions for documents and queries; Motivation of a heuristic estimate of the maximum likelihood optimization. [ABSTRACT FROM AUTHOR]

Fusion driven subcritical nuclear system (FDS) is a multifunctional hybrid reactor, which could breed nuclear fuel, transmute long-lived wastes, producing tritium and so on. This paper presents an introduction of FDS plasma design. Several different advance equilibrium configurations have been proposed and a 1.5-D discharge simulation of FDS was also present. [Copyright &y& Elsevier]

In this paper, an adaptive postprocessor figured with discrete cosine transform (DCT)-based block classification to effectively remove the so-called blocky effect from compressed video sequences is proposed. The proposed DCT-based detection algorithms for both intraframes and interframes require much lower computation complexity than the spatial-domain approaches. In order to preserve the edge information, the adaptive postprocessor is also designed with a DCT-based edge detection mechanism such that a one-dimensional median filter can be adaptively adjusted to match with the edge orientation. Simulation results show that the proposed DCT-based detection algorithms accurately classifies smooth, edge, or nonsmooth blocks to help the adaptive postprocessor to effectively remove the blocky effect and sharply preserve the edge information. [ABSTRACT FROM AUTHOR]

A novel heteronuclear complex, [CoCe(CH[sub2]C(CH[sub3])COO)[sub5](phen)(C[sub2]H[sub5]OH)][sub2] (where phen=1,10-phenanthroline), has been prepared and its structure determined by X-ray diffraction methods. The complex crystallizes in the triclinic system with space group P1, a=12.0982(8), b=12.6068(9), c=14.4492(10)Å, α= 67.388(1), β= 70.816(1), γ= 64.480(1)°. The structure was refined to R=0.045 for 5987 observed reflections (1> 2θ-(I)). The complex is a discrete tetranuclear molecule bridged by α-methylacrylato groups. Magnetic properties of the complex were also measured and are discussed. [ABSTRACT FROM AUTHOR]

Presents a study which proposed a novel rectifier topology for high power current source based alternating current motor drives. Features of the proposed rectifier topologies; Characteristics of a two-level buck converter based rectifier; Discussion on the typical switching pattern.

The title complex has prepared by the reaction of TbL 3 , Cu(NO 3 ) 2 and phen in H 2 O/EtOH (where L = α-methylacrylato; phen = 1,10-phenanthroline) and its structure determined by X-ray diffraction methods. The complex crystallizes in the triclinic space group P ī with Z = 1, a = 11.569(2), b = 14.584(3), c = 11.479(2) Å, α = 101.03(2), β = 104.37(2), γ = 74.01(1)°, and the structure was refined to R = 0.041 for 6463 observed reflections. The structure contains a discrete tetranuclear CuTbTbCu molecule. Copper(II) and terbium(III) are bridged by three bidentate carboxyl groups with a Tb ··· Cu separation of 3.9059(9) Å. The Tb ion is eight coordinate and exhibits a distorted square antiprism. The Cu ion is five coordinate and has distorted pyramidal geometry. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated a space vector controlled channel state information (CSI) drive for multimotor applications. Principle of active damping control; Space vector switching pattern; Experimental results and discussion.

Evaluates the effectiveness of using partitioning alcohol tracers in characterizing hydrophobicity of high-equivalent alkane number light, non-aqueous phase liquids (LNAPL). Thermodynamic model for predicting additional contaminant properties; Partitioning coefficients of alkanes; Importance of LNPAL characterization in the selection of surfactant system.

Features a study which characterized the P2 receptor subtype on canine trachael epithelial cells responsible for stimulating inositol phosphate accumulation and calcium mobilization using a range of nucleotides. Mechanism of action of mucus glycoproteins and ATP receptors; Methodology and results; Analysis of the results.

Discusses the conceptual structure and implementation of an integrated, computer-aided manufacturing system design environment, known as integrated and open computer-aided manufacturing system design (I/O-CAMSD). Feasibility of developing an integrated CAMSD framework to support the complete cycle of manufacturing operations; Task-centered approach.

Abstract: The effluent from the pulping of E. urophylla by alkali sodium sulfite chemi-mechanical process (AS-CMP) was characterized for its biodegradability by photosynthetic bacteria (PSB). Chemical coagulation post-treatment of biotreated wastewater was also studied. One-month continuous treatment in the laboratory indicated that the COD[sub Cr], BOD[sub 5] and SS removals in biotreatment stages reached 56%, 83% and 89% respectively, and the CH[sub 2]Cl[sub 2] extractives decreased from 10.7 mg/L to 7.7 mg/L. In chemical coagulation post-treatment stage, the effects of process conditions, such as coagulant dosage, pH value and the coordinated coagulation-flocculation treatment of three kinds of coagulants on coagulation effectiveness were discussed. The optimum operating conditions were given. [ABSTRACT FROM AUTHOR]

Excessive pesticide residues on Chinese cabbage will be harmful to people's health. Therefore, an identification system was designed for qualitative analysis of lambda-cyhalothrin residues on Chinese cabbage leaves. In order to extract discriminant information from mid-infrared (MIR) spectra of Chinese cabbage effectively, fuzzy uncorrelated discriminant vector (FUDV) analysis was proposed by introducing the fuzzy set theory into uncorrelated discriminant vector (UDV) analysis. In this system, the Cary 630 FTIR spectrometer was used to scan four samples of Chinese cabbage with different concentrations of lambda-cyhalothrin. The MIR spectra were preprocessed by standard normal variable (SNV) and Savitzky-Golay smoothing (SG). Next, the high-dimensional MIR spectra were processed for dimension reduction by principal component analysis (PCA). Furthermore, UDV, FUDV, and some other discriminant analysis algorithms were used for feature extraction, respectively. Finally, the K-nearest neighbor (KNN) classifier was employed to classify the data. The experimental results showed that when FUDV was used as the feature extraction algorithm, the identification system reached the maximum classification accuracy of 100%. The results indicated that FUDV combined with MIR spectroscopy was an effective method to identify lambda-cyhalothrin residues on Chinese cabbage. [ABSTRACT FROM AUTHOR]

Primary hepatic non-Hodgkin's lymphoma (NHL) is an extremely rare disease that is commonly neglected as a possible diagnosis. The present study reports the case of a middle-aged male with chronic hepatitis B in which primary hepatic NHL and rectal cancer occurred simultaneously. A large solitary tumor in the left lobe of the liver was incidentally detected on routine examination prior to the laparoscopic resection of the rectal cancer. Laparoscopic resection of the rectal cancer and a liver biopsy were performed simultaneously. The pathology revealed that the hepatic tumor was NHL and that the rectal cancer was adenocarcinoma. Systemic staging revealed no evidence of nodal or bone marrow involvement, therefore, primary hepatic lymphoma (PHL) was diagnosed. PHL associated with rectal adenocarcinoma is extremely rare and to the best of our knowledge, has never been reported. At present, the cause and most effective therapy for the condition remain unclear. [ABSTRACT FROM AUTHOR]