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Single- and dual-cathode DC magnetron sputtering was used to produce TiB 2 coatings and CN x /ZrN multilayers, respectively, with hardness exceeding 40 GPa. The composition, structure, topography, and mechanical properties were determined by various techniques, including Auger electron spectroscopy, X-ray diffraction, high-resolution electron microscopy, atomic force microscopy, and nanoindentation. An optimum combination of the sputtering pressure and substrate bias results in the production of ultrasmooth TiB 2 coatings with hardness up to 50 GPa and excellent wetting properties. The rationale for studying the CN x /ZrN system is that ZrN(111) provides excellent lattice match to the hypothetical β-C 3 N 4 (0001) face (β-C 3 N 4 was predicted to have mechanical properties comparable to diamond). Using a dual-cathode sputtering system, we produced crystalline multilayers of CN x /ZrN with bilayer thickness of 1-2 nm. Using various combinations of nitrogen partial pressure, target powers, and substrate bias, we found that the hardness of these coatings correlates very strongly with the occurrence of (111) texture of ZrN, consistent with the lattice-match strategy. Even with a ZrN volume fraction of 70 percent, such multilayer coatings have been synthesized with hardness in the 50 GPa regime.

Objective To present our experience with liver fine needle aspiration (FNA) diagnosis based on Riu's stain. Study design We reviewed a total of 322 liver fine needle aspirates from 286 patients seen in a seven-year period from April 1990 to April 1997 at Koo Foundation Sun Yat-Sen Cancer Center, Taipei. Surgical and/or clinical follow-up was available for confirmation in 292 aspirates. Results The cytologic diagnosis was categorized into four groups: benign in 81 cases, suspicious in 13, malignant in 225, and inadequate specimen in 3 cases. There were 16 false negative and no false positive diagnoses. Two suspicious aspirates were negative. Our results showed a sensitivity of 93.3% and a specificity of 100% for the detection of malignancy. If suspicious cases were considered positive, the specificity decreased to 95.1%, while the sensitivity increased to 93.6%. Among 87 hepatocellular carcinomas (HCCs) in our series, correct FNA diagnosis was made in 84 cases with an accuracy of 96.6%. Out of 135 cases of non-HCCs, 1 was incorrectly diagnosed. The accuracy of identifying a liver malignancy as non-HCC was 99.3%. Conclusion Cytologic features of HCC are well demonstrated by Riu's stain, with high accuracy in identifying them. Liver FNAs using Riu's stain combined with cell block study and clinicopathologic correlation can achieve very high sensitivity and specificity in the detection of hepatic malignancies.

Titanium diboride has many interesting physical and chemical properties that make it attractive as a tribological coating material. We focus our study on the relationship between hardness, crystal structure and processing parameters for TiB2 thin films produced by conventional and ionized magnetron sputtering. When synthesized by conventional magnetron sputtering, TiB2 films with the highest degree of crystallinity have the highest hardness and are obtainable at an optimum combination of argon pressure and substrate bias. The films also show strong (0001) texture. Such high degree of crystallinity can be obtained without substrate bias by ionized magnetron sputtering, in which enhanced ionization of the plasma is obtained by inductively coupling RF power in the region between the magnetron target and the substrate.

In power electronic module (PEM), IGBT (Isolated Gate Bipolar Transistor) is a high electrical power device and control wide power range from micro-voltage-ampere to mega-voltage-ampere. In addition, IGBT device usually operates in high-temperature environment, such as engine of automobile. As a result, the thermal problem is one of main concern regardless of the influence from dissipated power or environmental temperature. This paper discusses temperature distribution and mechanical behavior of wire bonding in IGBT based on finite element method. The purpose of this research would focus on the interface of wire bonding and connection substrate. Because the material of wire and substrate are different, it would result in CTE mismatch. Due to thermal damage, it could cause failure in the interface, e.g. wire bond lift off and heel crack. Among these, wire bond lift off is a critical failure and even lead to the degradation of IGBT. In order to simulate electro-thermal-mechanical behavior, two analytical methods are adopted in this research, one is electro-thermal analysis; the other is thermal-mechanical analysis. In this paper, we would use ANSYS software to analyze electro-thermal-mechanical behavior of wire bonding structure, furthermore, the wire bonding structure we build up is symmetrical, so only half of model is analyzed to save more time and reduce computational complexity. In electro-thermal analysis, we would show the temperature distribution in wire bonding structure when electric current is applied to wire. Furthermore, the natural convection and forced convection are taken into consideration in order to correspond to the realistic operational situation. The temperature change is dominated by Joule heating caused by the magnitude of electric current. For the purpose of obtaining the relation between temperature and electric current, nonlinear transient finite element simulation is proposed in this research. The analytical results show that the temperature would change along electric current and there is nearly temperature distribution in wire bonding structure after stopping applying electric current for a period of time. In thermal-mechanical analysis, we would adopt indirect coupling method, that is, use the results obtained from electro-thermal analysis as thermal load to thermal-mechanical analysis. According to analysis, the maximum von-Mises stress occurs in the heel of wire bonding due to CTE mismatch and high Joule heating. Besides, the displacement of wire bonding structure has upward direction, namely, the warpage phenomenon would occur due to temperature change. Under continuing of temperature change, it would bring fatigue failure in the interface of wire bonding and connection substrate. The objective in this research is to improve and increase the mechanical strength of wire bonding by discussing the relation of electro-thermal-mechanical behavior.

Telomeres are repeated GC rich sequences at the end of chromosomes, and shorten with each cell division due to DNA end replication problem. Previously, reprogrammed somatic cells of cloned animals display variable telomere elongation. However, it was reported that the cloned animals including Dolly do not reset telomeres and show premature aging. In this study, we investigated telomere function in cloned or transgenic cloned pigs, including the cloned Northeast Min pigs, eGFP, Mx, and PGC1α transgenic cloned pigs, and found that the telomere lengths of cloned pigs were significantly shorter than the nuclear donor adult fibroblasts and age-matched noncloned pigs (P0.05), indicating that nuclear reprogramming did not restore cellular age of donor cells after somatic cell nuclear transfer (SCNT). Trichostatin A (TSA), an inhibitor of histone deacetylase, has proven to enhance the efficiency of nuclear reprogramming in several species. In order to test whether TSA also can effectively enhance reprogramming of telomeres, TSA (40 nmol/L) was used to treat porcine cloned embryos at 1-cell stage for 24 h. Consistent with previous reports, the developmental rate of SCNT embryos to the blastocyst stage was significantly increased compared with those of the control group (16.35% vs. 27.09%, 21.60% vs. 34.90%, P0.05). Notably, the telomere length of cloned porcine blastocysts was also significantly elongated (P0.05). Although TSA did not improve the cloning efficiency (1.3% vs. 1.7%, TSA vs. control), the telomere lengths of cloned pig-lets were significantly longer compared with those of the control group and the donor fibroblasts (P0.05). In conclusion, telomeres have not been effectively restored by SCNT in pigs but TSA can effectively lengthen the telomere lengths of cloned pigs.

DNA damage response and repair pathways are important barriers to carcinogenesis. Here, we show that promyelocytic leukaemia (PML, also known as TRIM19), involved in sensing DNA damage and executing homologous recombination repair, is down-regulated in non-tumour liver cells surrounding hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). No PML mutation or deletion was found in HBV-infected liver or HCC cells. Immunohistochemical analysis of liver biopsies from patients with breast or liver cancer and HBV reactivation after chemotherapy revealed PML up-regulation and HBV exacerbation in normal liver tissue in response to DNA damage (functional PML), PML down-regulation in HCC peritumour cells associated with high HBsAg accumulation and low HBV replication activity (suppressive PML), and heterogeneous nuclear PML expression in HCC cells that lost HBV DNA and HBsAg and were non-reactive to DNA damage (dysregulated PML). Loss of PML in HBsAg-transgenic mice promoted chromosome breaks in liver cells and accelerated the accumulation of body and liver fat and the development of a liver steatosis-dysplasia-adenoma-carcinoma sequence in an inflammation-independent and male-predominant manner, compared to PML knock-out or HBsAg-transgenic mice during the same time period. These results indicate that PML deficiency facilitates genomic instability and promotes HBsAg-related hepatocarcinogenesis, which also involves androgen and lipid metabolism. These findings uncover a novel PML link between HBV-related tumourigenesis, DNA repair, and metabolism.

Thanks to the advancement of Ball Grid Array (BGA) technology, microelectronic packaging has become smaller, thinner and of a higher density and resilience than traditional packing technology. Ball Grid Array plays an important role in this technology and is utilized in many packages, such as Chip Scale Packaging (CSP), Wafer Level Packaging (WLP), Flip Chip (FC), and so on. Due to the requirements for miniaturization and the low cost, BGA has been widely applied in many applications. However, the solder joint fatigue life diminishes during mechanical loading. As microelectronic packaging is becoming more and more miniaturized, the solder joint fatigue life is getting worse in the strategy environment. It is therefore necessary to find a solution to this problem. In this study, a simulation-based design optimization methodology was developed for improving solder joint fatigue life in microelectronic packaging.

In the wake of the recent dramatic advances made in electronic products, product size has become smaller and smaller. As a result of this, electronic components will be affected easily by environmental factors such as humidity, pressure, and temperature. This paper discusses the flip chip packaging, which is affected by changes in temperature. Because the electronic components often failed by thermo-mechanical loadings, which leads solder joints to crack and separate with HIC (Hybrid Integrated Circuit) and PCB (Printed circuit board). Solder joints are the interconnections of the flip chip assemblies, and they are also responsible for transferring signals. Thus, they are the most important components in the flip chip assemblies. Hence, this paper mainly analyzes the largest stresses that occur in the solder joints, and establishes the relationship of the geometries and the material properties. Then, possible ways of changing flip chip parameters to improve the reliability of the flip chip structure are discussed. This research uses ANSYS software, which is based on finite element theory in order to reduce time used and save money, as finite element simulation provides results more quickly and cheaply than experiments. Besides, it can also predict the reliability of the flip chip. Finally, presenting the simulation results and contrasting these with the theoretical results provides good accuracy. The simulation results are able to provide the optimal design of flip chip assemblies.

The influences of thermo-mechanical loadings on BGA's solder joint are discussed in this paper. Since the thermo-mechanical loading caused by mismatch of coefficient of thermal expansion between different materials is a very common and unavoidable phenomenon in electronic packaging. Many products like mobile phones, PC suffer from this loading. It goes without saying that it's a problem, especially in a rapid changing temperature cycle, needed to be solved and conquered. The major objectives of this paper is to build up an analytic thermo-mechanical model which is capable of analyzing solder joint's behaviors such as forces, bending moments and present the results from this model in an effort to provide design reference. The comprehension of solder joint can contribute to make assembly more reliable. The finite element model (FEM) program is chosen as the computational method. What's more, the method of simulation is equipped with the advantages, including saving time, low costs and so on. We can even predict the reliability of products by a proper model prior to mass production. In general, the solder joint is the key aspect in the whole packaging's structure. In addition, the difference between lead and lead-free solder joint are also discussed and compared in this paper due to the fact that the demand of environment concerns has been highly considered for the past decades. In this paper, through using the finite element analysis, the model has been established, and the results acquired from analytical model should be applied to FEM predictions.

Amniotic fluid stem cells (AFSCs) are multipotent stem cells that may be used in transplantation medicine. In this study, AFSCs established from amniocentesis were characterized on the basis of surface marker expression and differentiation potential. To further investigate the properties of AFSCs for translational applications, we examined the cell surface expression of human leukocyte antigens (HLA) of these cells and estimated the therapeutic effect of AFSCs in parkinsonian rats. The expression profiles of HLA-II and transcription factors were compared between AFSCs and bone marrow-derived mesenchymal stem cells (BMMSCs) following treatment with γ-IFN. We found that stimulation of AFSCs with γ-IFN prompted only a slight increase in the expression of HLA-Ia and HLA-E, and the rare HLA-II expression could also be observed in most AFSCs samples. Consequently, the expression of CIITA and RFX5 was weakly induced by γ-IFN stimulation of AFSCs compared to that of BMMSCs. In the transplantation test, Sprague Dawley rats with 6-hydroxydopamine lesioning of the substantia nigra were used as a parkinsonian-animal model. Following the negative γ-IFN response AFSCs injection, apomorphine-induced rotation was reduced by 75% in AFSCs engrafted parkinsonian rats but was increased by 53% in the control group after 12-weeks post-transplantation. The implanted AFSCs were viable, and were able to migrate into the brain's circuitry and express specific proteins of dopamine neurons, such as tyrosine hydroxylase and dopamine transporter. In conclusion, the relative insensitivity AFSCs to γ-IFN implies that AFSCs might have immune-tolerance in γ-IFN inflammatory conditions. Furthermore, the effective improvement of AFSCs transplantation for apomorphine-induced rotation paves the way for the clinical application in parkinsonian therapy.

This paper will focus on the fast assessment methodology of FBGA fatigue life through simulation and physics of failure (PoF) analysis under thermal cycle. The structure of fine pitch ball grid array (FBGA) that has been investigated, and been modeled by ANSYS to compare with experimental data. There are two temperature cycling will be used, one is used to verify FEA model, and the other one is used to do failure analysis. The aim of this paper is fist discussing the ability of finite element analysis (FEA) in executing the virtual thermal cycling reliability analyzing the reliability of solder joints fatigue life in local modeling. FBGA packages can warp due to local and global mismatch of the coefficients of thermal expansion and the asymmetric package geometry. Temperature cycling condition including dwell time and ramp rate is an important factor that will affect the solder joins reliability. This paper will identify the critical parameters that influence by using a Design of Experiments (DoE) approach using simulation results from ANSYS. Two types of analyses include the physics-based analysis and the statistical-based analysis. The paper presents the physics-based analysis, three steps, uses by DoE tool. The first step we have to select the parameters, such as PCB thickness, PCB Young's modulus, PCB coefficient of temperature expansion (CTE), solder joints height, die thickness, mold compound thickness, and so on. The second step is to find important factors. And the final step is going to DoE, in this paper used response surface methodology (RSM). The use of DOE and ANOVA to identify the critical parameters and a response surface to generate a functional form will be discussed. In this study, we will concentrate on the approach of deformation information to the critical stress. The critical stress is then fed into a fatigue damage model, which outputs life, or cycles to failure. Throughout the work, DoE and ANOVA techniques will be used to determine the key parameters and help in the development of a fast assessment model of FBGA fatigue life through simulation and physics of failure (PoF) analysis under thermal cycle.

In the multilayered printed circuit board (PCB), the signal transmission between different layers occurs by way of through hole structure. The geometry of a through hole consists of traces, pads and a perfectly conducting hollow cylinder. Conductive Anodic Filament (CAF) generated easily in PCB when board size is decreased. CAF produced will lead to leakages or short circuit. Many reasons cause the phenomenon of the CAF, one of them is the voltage. In these situations, the signal transmission integrity is concerned. The excessive capacitance is generated near the through hole structure. Such capacitance influences the signal transmission between different layers. A number of factors can cause excessive capacitance, for example: geometry of transmission line, pad of through hole and the interaction of different layers. However, recent application of the multilayered printed circuit board such as cell phones and note books, have decreased the broad size for easy to carry or load more equipment. Decreasing the size of PCB, the excessive capacitance near the through hole structure is inevitable. It is more important to design the complexity of the layout and the geometry of structure. The quick and efficient prediction of the performance is concerned when manufacturing process become more complicated. The simulation model and problem discussion are the subject of this paper. In this study, we demonstrate that the geometry of the transmission line near the through hole may affect the transmission of the signal by excessive capacitance. By using ANSYS 12 to simulate the high frequency electromagnetism, and simulate the transmission line with different shapes near the through hole and extract the Scattering-parameters from the simulation results. Scattering-parameters are used to describe the electrical behavior of linear electrical network. The parameters are helpful for us to design electrical engineering, electronics engineering, and communication systems, and especially for microwave engineering. By comparing Scattering-parameters of different structures, we can understand the signal transmission and reflectivity between two layers. We also analyze the electric field and magnetic field of the structure, and use a method based on the quasi-static approximation to compute the excessive capacitance of the through hole structure. Using the concept of equivalent circuit to convert the original model into the RLC circuit. Equivalent circuit is divided into multiple series parts. Many parameters such as resistance, capacitance, inductance and characteristic impedance will be discussed, then compare these value changes between different shapes of the transmission line near the through hole. The ANSYS model is proposed to simulate the high-frequency electromagnetic of the structure. By these model, we want to predict the signal transmission performance of the through hole structure.

Quality and microstructure of materials are strongly affected by the shapes of pores in solids, which are encountered in almost all the packaging, micro-electro-mechanical systems (MEMS), and manufacturing fields. This study theoretically analyzes the mechanisms of an entrapped micro-bubble as a pore in the solid. A phase diagram, as introduced previously to be satisfied by interfacial normal stress balance, can be used to control and delineate the growing path and final shape of a pore. The predicted pore shape agrees with experimental results.

Uncompleted epigenetic reprogramming is attributed to the low efficiency of producing transgenic cloned animals. Histone modification associated with epigenetics can directly influence the embryo development and transgene expression. Trichostatin A (TSA), as an inhibitor of histone deacetylase, can change the status of histone acetylation, improve somatic cell reprogramming, and enhance cloning efficiency. TSA prevents the chromatin structure from being condensed, so that transcription factor could binds to DNA sequence easily and enhance transgene expression. Our study established the optimal TSA treatment on porcine donor cells and cloned embryos, 250 nmol/L, 24 h and 40 nmol/L, 24 h, respectively. Furthermore, we found that both the cloned embryo and the donor cell treated by TSA resulted in the highest development efficiency. Meanwhile, TSA can improve transgene expression in donor cell and cloned embryo. In summary, TSA can significantly improve porcine reconstructed embryo development and transgene expression.

This paper summarizes the force calculation at each pitch position for the structure, where a component (overmold, die, and BT) is attached to a PCB (printed circuit board) through an array of solder joints with an external bending moment applied at the ends of PCB. In this paper, the results from the model proposed by E. Suhir [1] are summarized with corrections in the derivation of the equations. Details of the new model will be described including the methodology, the formulation and the simulated results. Comparisons between the two models will be made with discussions. In this new model, each solder joint between the component and the PCB is replaced by a spring with spring constant. Benefiting from the symmetry of the structure, only half of the structure needs to be considered which simplifies the formulation of the problem and saves the computation time dramatically. The variables (unknowns) to be solved are the forces exerted on each spring due to applied external bending moment. In the subsections to come, detailed derivations will be given followed by numerical results. The setup of the new model and it is essentially the same as the Cantilever-intermediate load problem. The forces exerted on each spring will be solved through a system of linearly independent equations governed by the following conditions. All the listed formulas above are for the case when the number of leads is odd. Basically, similar formulas will be used for the case when the number of leads is even. The goal in this paper will be as follows: (a) Suhir's model deals with continuous case. It is clearly seen from the simulation results of Suhir's model that all the curves are smooth no matter how many number of solder joints are involved. The only parameter that is related to the number of joints as defined by Suhir is the spring constant of the elastic attachment. In the new model, we will solve for the force at each position in a discrete sense. That is why the curves are not that smooth when the number of solder joints is small. As the number of the solder joints becomes large (or in other words, the pitch size is small), the two models yield exactly the same results. (b) Mathematically, the new model is simpler and straightforward. The only math involved is solving the linearly independent system of equations. In Suhir's model, however, the solution process starts from solving the 4th order differential equations. Although analytical solutions can be obtained, special attention has to be paid in imposing proper boundary conditions, which might not be trivial.

The global model uncertainty analysis is to estimate the error due to input data approximations rather than sensitivities associated with finite element modeling. In this paper, estimates will be made on the amount of sensitivity in the global modeling which basically involves the sensitivity in the value of the material properties, input loadings, and geometries. Assume the model structure is corrected, how do we estimate a physics of failure (PoF) and predict time to failure or cycle to failure? Identifying an approach for quantifying the combination of input and uncertainty would enable the determination of more realistic confidence limits on Physics of Failure (PoF) predictions. The physics-of-failure (PoF) approach to reliability utilizes knowledge of the life-cycle load (thermal, vibration, mechanical, electrical, photonics, and so on) profile package architecture and material properties to identify potential failure mechanisms and to prevent operational failures through robust design and manufacturing practices. We can decompose the elements of any mathematical model into the physical parameters used in forming equations, such as material properties or geometric dimensions and the model structure, which results from simplifications, assumptions and approximations. Variability in the physical parameters can be addressed by existing stochastic methods, which are designed to propagate probability distributions on the parameters through a fixed model structure in order to estimate the statistics of interest on the model response quantities.

Microelectronic devices are often subjected to environmental and power cycling thermal loads. Thermal cycling and the shear forces lead to many failures in microelectronic devices. The most common failure is an open in one or more of the input/output (I/O). The open is the result of a cracked or damaged interconnects, whether it is a lead-free solder joint. Thermal cycling can occur for a device being turned on and off, a system containing the device being turned on and off, an environmental load, and so on. The most important issue that must be addressed in order to the critical issue is the magnitude of the shear force on the lead-free solder joint under thermal loading, in other words, how many cycles can a microelectronic device survive before a failure occurs. The shear forces are often caused by the global coefficient of thermal expansion (CTE) mismatch between the component and the printed circuit board (PCB). This can be a cyclic load when the microelectronic device is repeatedly subjected to a range of temperatures. Shear forces in the lead-free solder joints are an important aspect of the microelectronic package failure problem because the shear force is directly related to the microelectronic device life. A failure model can be used to predict the fatigue life of a microelectronic device in terms of cycles to failure. The Vandevelde analytic model [1] for determining shear forces in the lead-free solder joints of electronic devices, which is based on elastic strength of materials principles, is critiqued in this paper. This analytic model is then used to gain insightful information regarding interconnect shear force behavior. The results from this new model were compared to finite element model results to assure the analytic model was accurately capturing the behavior of the forces in the lead-free solder joints. The results from the investigations must be qualified by stating that the assumptions of constant pitch, homogeneous component, and linear elastic materials were utilized. The completion of this new model leads to a more comprehensive solution to the problem of accurately and efficiently characterizing shear forces in the lead-free solder joint of microelectronic packages and ultimately predicting the life of the packages. Conclusions are made concerning the influence of the number of the lead-free solder joints, device geometry, and material properties on the resulting shear forces. Rapid assessment methodologies for efficiently designing a successful microelectronic package are presented in this paper, which can save both time and money in the design process.

Solder joint fatigue life models will be used for analysis in this paper. Identifying an approach for quantifying the combination of input and uncertainty would enable the determination of more realistic confidence limits on PoF predictions. Variability in the physical parameters can be addressed by existing stochastic methods, which are designed to propagate probability distributions on the parameters through a fixed model structure in order to estimate the statistics of interest on the model response quantities. This paper focuses on uncertainly analysis, that is, how the input data uncertainly affects the output data uncertainly. We are assuming the model is correct and are only dealing with uncertainties due to variations in inputs. Output uncertainty, uncertainly in the correction factor, is determined by Monte Carlo simulation.

A carbon nitride phase with primarily sp3-bonded carbon is stabilized in CNx/ZrN superlattice coatings. Rutherford backscattering spectrometry measurements give a N/C atomic ratio ∼1.3 for the CNx layers. High-resolution transmission electron microscopy and Z-contrast imaging from the superlattice show a well-defined layer structure. Raman and near-edge x-ray absorption fine structure spectroscopy results reveal the formation of sp3-bonded carbon atoms in short-period CNx/ZrN superlattices.

Semiconductor component manufacturers supply to different products in a wide range of market segments, and therefore the end use conditions may not always be known. Qualifying a semiconductor component or demonstrating that it can operate reliably under use conditions can therefore be a challenging task. The goal of this paper is to describe the challenges in semiconductor component qualification and demonstrate how use conditions and product configuration can influence reliability and therefore qualification test selection. Industry practices on component qualification are summarized and an ideal component qualification plan that takes into account end use conditions and product configuration is described.

Liver receptor homolog-1 (LRH-1; NR5A2) is an orphan member of the nuclear receptor superfamily, mainly expressed in endoderm-derived tissues and in the ovary. In ovarian granulosa and luteal cells, LRH-1 regulates the expression of genes associated with ovarian steroidogenesis. LRH-1 can be transported to transcriptionally inactive nuclear bodies after conjugation with small ubiquitin-related modifier (SUMO). In the present study, we investigated the effects of SUMO modification at five lysine residues of LRH-1 in rat granulosa cells. Lysine 289 could be conjugated with SUMO-1 in vitro, and the mutation K289R increased transcriptional activity of LRH-1, suggesting that SUMO conjugation is associated with transcription repression. Coexpression of SUMO-1 targets LRH-1 to the dot-like nuclear bodies, but the effect of lysine mutations on blocking subnuclear localization depended on the cell type. In COS-7 cells, mutation of either K173 or K289 prevented SUMO-1-mediated translocation of LRH-1 into nuclear bodies and also reduced the conjugation by SUMO-1, suggesting that K289 and K173 are two important sites involved in SUMO-1 modification. In granulosa cells, three or more altered lysine residues were required for nucleoplasm retention. This result suggests that multiple lysine residues are targets for SUMO conjugation in vivo and granulosa cells are more sensitive to SUMO-1-mediated LRH-1 localization to nuclear bodies. Nuclear body localization of LRH-1 was suppressed by forskolin and cholera toxin. Forskolin treatment obviously influences the expression of members involved in the SUMO pathway. The results obtained in the present study suggest that cAMP signaling could change the dynamic process of sumoylation and repress LRH-1 targeting to nuclear speckles in rat granulosa cells.

The developmental potential of reconstructed embryos varied according to the source of donor cells, it was thought that the donor cells capabilities to be reprogrammed were different. We established the method of culturing porcine bone marrow mesenchymal stem cells (pMSCs), identified and observed the growth characteristics of pMSCs, and determined pMSCs reprogramming potential as donor cells for nuclear transfer (SCNT). We found that the method of gradient centrifugation to isolate pMSCs from porcine bone marrow was better than the method of anchoring culture; the number of pMSCs achieved peak at day 6, the adhesive rate of cultured cells was 78.50% at 10h and the division index of cultured cells was 24.00 per thousand at day 4. The developmental competence were compared among three kinds of embryos, reconstructed embryos with PF and pMSCs, Parthenogenetic. The blastocysts rate and total cell number of blastocysts were 15.07%, 14.63% vs 30.91% and 24.1 +/- 6.5, 30.67 +/- 17.7 vs 25.8 +/- 11.4. These results indicated that pMSCs could be high proliferation and stable growth characters in vitro, and were suitable donor cells type for nuclear transfer.

Ball Grid Array BGA packages are a relatively new package type and have newly become the package style of choice. Much high density, high I/O count semiconductor devices are now only offered in this package style. Designers are naturally concerned about the robustness of BGA packages in a vibration environment when their experience base is with products using more traditional compliant gull or J leaded surface mount packages. Because designers simply do not have the experience, tools are needed to assess the vibration fatigue life of BGA packages during early design stages and not have to wait for product qualification testing, or field returns, to determine if a problem exists. The new assessment methodology proposes in this paper.

Natural killer (NK) cells are important effectors of the innate immune system, which exhibits cytolytic activity against infectious agents and tumor cells. NK cells are derived from CD34(+) hematopoietic stem cells (HSCs). Human umbilical cord blood (UCB) has been recognized as a rich source of HSCs. Previously, we have reported an optimized serum-free medium for ex vivo expansion of CD34(+) cells from UCB. In this study, the serum-free, expanded CD34(+) cells were tested to differentiate into NK cells and their induction kinetics. After 5 weeks of induction, the induced NK cells were characterized by analysis of surface antigens, IFN-gamma secretion, and cytotoxicity against K562 cells. The results indicated that NK cells derived from the serum-free, expanded CD34(+) cells exhibited both characteristics and functions of NK cells. Furthermore, the serum-free, expanded CD34(+) cells showed a significantly higher NK cell differentiation potential than freshly isolated CD34(+) cells. NK cells induced from serum-free, expanded CD34(+) cells showed a higher concentration of IFN-gamma secretion and ability of cytotoxicity than those from freshly isolated CD34(+) cells. Therefore, ex vivo-expanded CD34(+) cells in optimized serum-free medium could differentiate into NK cells and provided a promising cell source for immunotherapeutic approaches.

With glucose as co-substrate, anaerobic degradation kinetics of 2,4-dinitrophenol (2,4-DNP) were investigated in batch culture. The results show that 2,4-DNP and glucose can be degraded by the bacteria simultaneously. Although the effect of COD on 2,4-DNP degradation was minimal, addition of 2,4-DNP effected COD degradation obviously. The rate of 2,4-DNP degradation increased with increasing initial 2,4-DNP concentrations up to 225 mg/L. Further increase in initial 2,4-DNP concentrations caused decrease in the rate of degradation because of substrate inhibition. Uncompetitive inhibition equation is proposed to describe the degradation of 2,4-DNP. With non-linear regression technology, the kinetic model parameter q(max), K(s) and K(i) are found to be 3.24 mg/(h x g), 196.23 mg/L and 165.91 mg/L respectively. The experimental data verification for the model equation is satisfactory.

To study the relationship between aldehyde dehydrogenase (ALDH) gene polymorphism and alcoholic liver disease, and investigate the genetic pathogenesis of alcoholic liver disease (ALD).PCR, restriction endonuclease and electrophoresis were used, to detect the genotypes and alleles frequencies of ALDH gene in patients in the control group, alcohol dependent group and ALD group, and each group contained 20 patients.The frequencies of ALDH2*1 and ALDH2*2 allele had statistic significance between control group and ALD group (x2=4.80, P0.05), and no statistic significance between control group and alcohol dependent group. ALDH2*1/*1 was predominant in alcohol dependent group and ALD group, while ALDH2*2/*2 was not detected.The gene polymorphism of ALDH is close to ALD. The allele of ALDH2*2 may be a negative risk factor for the developing of ALD

Over the past 30 years, the beneficial therapeutic effects of selected low energy, time varying electromagnetic fields (EMF) have been documented with increasing frequency to treat therapeutically resistant problems of the musculoskeletal system. However, the underlying mechanisms at a cellular level are still not completely understood. In this study, the effects of extremely low frequency pulsed electromagnetic fields (ELF-PEMF) on osteoclastogenesis, cultured from murine bone marrow cells and stimulated by 1,25(OH)(2)D(3), were examined. Primary bone marrow cells were cultured from mature Wistar rats and exposed to ELF-PEMF stimulation daily for 7 days with different intensities of induced electric field (4.8, 8.7, and 12.2 micro V/cm rms) and stimulation times (0.5, 2, and 8 h/day). Recruitment and authentication of osteoclast-like cells were evaluated, respectively, by determining multinuclear, tartrate resistant acid phosphatase (TRAP) positive cells on day 8 of culture and by the pit formation assay. During the experiments, cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin 1-beta (IL-1beta), and prostaglandin-E(2) (PGE(2)) were assayed using the enzyme linked immunosorbent assay (ELISA). These findings suggest that ELF-PEMF can both enhance (approximately 50%) and suppress (approximately 27%) the formation of osteoclast-like cells in bone marrow culture, depending on the induced electric field intensity. In addition, consistent correlations were observed between TNF-alpha, IL-1beta, and osteoclast-like cell number after exposure to different induced electric field intensities of ELF-PEMF. This in vitro study could be considered as groundwork for in vivo ELF-PEMF clinical applications on some osteoclast-associated bone diseases.

A tryptophan catabolizer, indoleamine 2,3-dioxygenase (IDO) is highly expressed in the placenta and plays an essential role in maternal tolerance. Recent data have shown that the administration of an IDO inhibitor blocked not only maternal tolerance but also liver allograft tolerance. However, little is known about the induction of IDO in liver allografts, although a gene specific for tryptophan 2,3-dioxygenase (TDO) is believed to be expressed in the liver. In the present study, we investigated whether IDO is induced in liver allografts. Synthetic oligonucleotide primers based on the mouse IDO cDNA sequence were used to amplify RNA derived from livers of donor, syngeneic or allogeneic OLT rats. RNA encoding IDO was induced in the rat allogeneic liver after orthotopic liver transplantation (OLT), but not in syngeneic OLT. The rat nucleotide sequence of the RT-PCR products obtained from OLT livers revealed identities of 89% homology to the mouse IDO and of 68% to the human IDO. This study demonstrated the presence of RNA encoding IDO in allogeneic OLT livers, which may be involved in the immune response after liver transplantation.

The results of the experimental study of CoX/Pd multilayer based recording layers for perpendicular recording media are presented. The perpendicular magnetic recording media with multilayer recording layers and high moment soft underlayers were deposited by magnetron sputtering. It is shown how a favorable microstructure of the multilayer films can be achieved by the use of the appropriate buffer layers. The effects of boron addition to the cobalt layer in a multilayer recording layer is described. The feasibility of the aging process that leads to the reduced exchange coupling in the multilayer recording layer, is demonstrated. It is shown that boron addition to the cobalt layer accelerates the aging process.

The propagation of elastic waves in one-dimensional (1D) phononic crystals (PCs) with functionally graded materials (FGMs) is studied using the spectral finite elements and transfer matrix methods. FGMs typically treat the graded interlayer as a system of discrete layers, and the material properties are varied according to a well-known rule, such as the power law. The 1D PCs are composed of both FGMs and isotropic materials, and their band gaps can be changed with different FGM compositions and geometry parameters. By selecting the appropriate parameters, the desired filters can be designed.

Vibration loading has become very important in the reliability assessment of modern electronic systems. The objective of this paper is to develop a rapid assessment methodology that can determine the solder joint fatigue life of ball grid array (BGA) and chip scale packages (CSP) under vibration loading. The current challenge is how to execute the vibration fatigue life analysis rapidly and accurately. The approach in this paper will involve global (entire printed wiring board (PWB)) and local (particular component of interest) modeling approaches. In the global model approach, the vibration response of the PWB will be determined. This global model will give us the response of the PWB at specific component locations of interest. This response is then fed into a local stress analysis for accurate assessment of the critical stresses in the solder joints of interest. The stresses are then fed into a fatigue damage model to predict the life. The goal is to retain as much accuracy and physical insight as possible while retaining computation efficiency.

In this paper, we study the defect bands of a 1D phononic crystal consisting of aluminum (Al) and polymethyl methacrylate (PMMA) layers with a dielectric elastomer (DE) defect layer. The plane wave expansion (PWE) method and supercell calculation are used to calculate the band structure and the defect bands. The transmission spectra are obtained using the finite element method (FEM). Since the thickness of the dielectric elastomer defect layer is controlled by applying an electric voltage, the frequencies of the defect bands can be tuned. A narrow pass band filter can be developed and designed by using the dielectric elastomer.

This study investigates the nondiffractive propagation of sound waves in two-dimensional sonic crystals consisting of rectangular rods with a slit. The plane wave expansion method is used to calculate the equifrequency surfaces of sonic crystals with a square lattice. At certain frequencies, straight contour lines in the equifrequency surfaces are found. That frequency is strongly dependent on the geometric sizes of the rectangular rods. Further, the nondiffractive propagation of the sound wave can be realized for omnidirectional incident angles, and the properties can be applied to design novel acoustic devices.

The occurrence of profound hypoglycemia in a patient with metastatic adenocarcinoma of the pancreas is reported. In contrast to the four previously reported cases, no suggestion of excess insulin production was found. Metabolic studies in this patient suggest both increased peripheral glucose utilization and decreased hepatic glucose production as contributing factors which promoted the hypoglycemia.