bluuebunny/crossref_metadata_2025 huggingface dataset:
Design to Succeed: Integrated MEMS Development
Authors: Finch Nora
Published: June 2008

Designers of Micro-Electro-Mechanical Systems (MEMS) face many challenges by being forced to meet product specifications within the limitations of processing and thin-film material parameters. To create a successful MEMS product, there must be collaboration between experts in the target industry and MEMS experts in processing, materials, and other relevant technologies. The use of an integrated CAD for MEMS™ tool by all parties involved can greatly reduce the number of design and fabrication iterations required to successfully commercialize the product. Leveraging Corning IntelliSense’s over ten years of experience in the development of MEMS, IntelliSuite® provides a unified development platform for process development, thin-film material engineering, mask layout, and device and package analysis. Here we will outline a proven strategy for cost-effective, rapid product development.
Residual Stress Analysis of Silicon-Aluminum-Glass Bonding Processes
Authors: Bystrom Delney , Lin Liwei
Published: June 2008

This paper presents a residual stress analyses based on two bonding systems, silicon-aluminum-glass and silicon-aluminum-quartz, for MEMS packaging applications: The predicted residual stress generated in the Pyrex glass bonding system is 60 to 74 GPa that is close to the fracture strength of Pyrex glass at 69 GPa. In the quartz bonding system, the predicted residual stress is 100 to 207 GPa that far exceeds the fracture strength of Quartz at 48 GPa. Experimental results are consistent with analytical predictions that small cracks are found in the glass bonding system and big fracture lines are observed in the quartz bonding system. As such, this residual stress analysis model serves as an excellent tool to assist the development of new bonding systems in the areas of material selection, geometrical design of the bonding area and the dimensions of the bonding solders.
Linear Programming Performance Bounds for Markov Chains With Polyhedrally Translation Invariant Probabilities and Applications to Unreliable Manufacturing Systems and Enhanced Wafer Fab Models
Authors: Morrison James R. , Kumar P. R.
Published: June 2008

Our focus is on a class of Markov chains which have a polyhedral translation invariance property for the transition probabilities. This class can be used to model several applications of interest which feature complexities not found in usual models of queueing networks, for example failure prone manufacturing systems which are operating under hedging point policies, or enhanced wafer fab models featuring batch tools and setups or affine index policies. We present a new family of performance bounds which is more powerful both in expressive capability as well as the quality of the bounds than some earlier approaches.
Numerical Study of Operability of Combustor With Inflow Oscillations
Authors: Su K. , Zhou C. Q.
Published: June 2008

Numerical study of gas turbine combustion with the inflow oscillation has been conducted using KIVA-3V code. The simulation was based on the solution of Navier-Stokes equations with a time-marching method and models of turbulence and sprays, and a simplified kinetic mechanism of 17-species and 23-step. The transient inflow was assumed by specifying the pressure oscillation in a form of sinusoidal function. Effects of three flow patterns, i.e. quasi-steady, transition and steady patterns corresponding to the oscillation frequency ranges of n ≤ 80, 80 ≤ n ≤ 320 and n ≥ 320 Hz, on combustion performance were investigated. It is found that for the flow in quasi-steady pattern, combustion is in quasi-steady state with flow and combustion properties dependent of time and the analytical approaches for steady combustion can be applied; for the flow in steady pattern, combustion can be treated as if in steady state and the influence of oscillation can be ignored; and in transition pattern, the combustion behaves in-between. Finally, the operability of combustor with inflow oscillation was analyzed, which is useful for the analysis of combustion performance under irregular inflow conditions.
Numerical Simulation of Combustion Air Systems for Large Industrial Boilers
Authors: Jorgensen Kris L. , Wessel Richard A. , Strempek Joseph R.
Published: June 2008

Combustion air systems are an important aspect of the performance of industrial boilers and are increasingly being used as an integral means of reducing emissions. With the wide range of unique air system designs presently deployed, traditional methods of analyzing performance, based on experience, have become more difficult and less reliable. Numerical simulations are currently being used as a tool to analyze the operation and design of these air systems and how they relate to boiler performance and emission control. A proprietary CFD combustion code has been applied to a wide range of industrial boilers. Recent results from three selected studies are presented. These case studies demonstrate the benefits of using numerical simulation to: 1) analyze and optimize an existing air system, 2) validate an upgrade design, and 3) design and develop a new air system concept.
Aspheric Micro-Lens-Array Fabricated by Excimer Laser Dragging
Authors: Wang Gou-Jen , Cheng Wei-Leun , Yang Jauh-Jung , Pan Cheng-Tang
Published: June 2008

This article investigates the fabrication processes of the three-dimensional microstructure by using excimer laser dragging method. To systematic control the dimensions and shape of the ablation depth and reduce the time-consuming parameter tuning labors, b both the linear regression and the nonlinear neural network approaches are employed by adapting the preliminarily experimental data to model the fabrication process. Further experiments are then conducted to verify the established fabrication models. Finally, the relationship between the controlled parameters such as height of the mask, moving speed of the mask, energy of the laser pulse and the ablation depth of the work piece are elaborately investigated.
Analysis and Design of Multistage Electrostatically-Actuated Micro Vacuum Pumps
Authors: Astle Aaron , Paige Anthony , Bernal Luis P. , Munfakh Jennifer , Kim Hanseup , Najafi Khalil
Published: June 2008

A new concept for a MEMS-fabricated micro vacuum pump is proposed. The pump is designed to operate in air and can be easily integrated into MEMS-fabricated micro fluidic systems. The pump consists of a series of pumping cavities with electrostatically actuated membranes interconnected by electrostatically actuated microvalves. A thermodynamic model of the micropump has been developed and used to determine the pump performance. It is shown that volume ratio plays an important role in the operation of the pump. For a fixed number of stages, at high volume ratio, pumping action is uniformly distributed among the stages. In contrast, at low volume ratio most of the pumping takes place in the latter stages of the pump. Detailed calculations of the flow through key components of the micropump are also reported. In particular the flow through a checkerboard microvalve and electrode perforations is discussed, and new correlations for the pressure loss in these components are proposed.
Analysis of a Composite Piezoelectric Circular Plate With Initial Stresses for MEMS
Authors: Wang Guiqin , Sankar Bhavani V. , Cattafesta Louis N. , Sheplak Mark
Published: June 2008

The paper presents a mechanical analysis of the multi-layer circular composite plate For MEMS devices. Each layer of the plate is assumed to have different radius, material properties and initial stresses. Governing equations for the composite plate are derived based on the classical laminated plate theory, and analytical soultions have been developed for static deflection of the initially stressed plate due to transverse pressure loading as well as for a given electric field in the piezoelectric layer. A nonlinear finite elernent analysis of the plate is also performed. The analytical result match the FE results for the range of parameters used in the microphone design. The analytical model will be useful in the design and optimization of MEMS devices containing circular piezoelectric composite plates and diaphragms.
Thermal Finite Difference Analysis of Threshold Heating for Nanoscale Machining
Authors: Trinkle Chris A. , Smith Phil , Vallance R. Ryan , Wong Basil T. , Mengu¨c¸ M. Pinar
Published: June 2008

We are investigating a new manufacturing process utilizing Threshold Heating and Emission from Nanotubes (THEN) to remove clusters of atoms from workpiece surfaces. A pulsed laser will locally heat a workpiece to the threshold temperature, and then electrons emitted from nanotube tips will create nanoscale features within the heated zone. This paper concentrates on modeling the temperature distribution in the workpiece caused by radiation and conduction transfer. Our finite difference model considers a Gaussian laser beam radiating through a transparent substrate onto a metallic workpiece layer. The finite difference model will eventually be integrated with thermal models of electron emission and absorption to achieve a complete model of the THEN process.
Fabrication of a Two-Way Pressure Regulation Micro Valve With the Anti-Siphon Effect
Authors: Lee Sang Wook , Yoon Hyeun Joong , Yang Sang Sik
Published: June 2008

This paper presents the fabrication and the test of an implantable two-way pressure regulation micro valve with the anti-siphon effect for the hydrocephalus patients. This micro valve consists of a silicone rubber membrane and a valve seat to enable the opening pressure control as well as the anti-siphon behavior. The two-way pressure regulation and the anti-siphon effect of the micro valve are shown experimentally for various sizes of membranes and valve seats.
Deformation Fields in Woven Composite Plates Under Impact
Authors: Bahei-El-Din Y. A. , Zikry M. A. , Rajendran A.
Published: June 2008

The deformation fields and kinematics of woven composite material systems due to impact loads are analyzed and characterized for various structural parameters. Target plates comprised of woven composites with 3D preforms are considered. The analysis examines fully consolidated as well as cellular systems and simulates actual experiments. Solution of the nonlinear dynamic/contact problem was obtained by a meso-mechanics based finite element model. The results quantify experimental observations, which reveal distinct behavior under impact among nonporous and porous systems. It was found that wave propagation effects at incident energies in the order of 500 J are significant and lead to penetration at the impact face. Localized shear damage in the 3D woven system precede penetration in both the nonporous and the porous systems. The porous system is capable of dissipating more energy prior to penetration due to containment of local damage, which emanates from the void boundaries, within subsurface locations.
Nonlinear Deformation of Woven Fabrics
Authors: Taban Faruk , Luo Shen-Yi
Published: June 2008

The large deformation of plain-weave fabrics consist of bundle yarns under biaxial loading is examined by a sinusoidal model. The nonlinear properties, flattening and transverse shear effects of the bundle yarn, as well as the yarn’s crimp interchanges are considered in this study. The constitutive equations are derived from the energy method. Comparison is made with the uniaxial experimental result, and the biaxial behaviors of the fabric are predicted and discussed.
Stress Analyses and Structural Modifications of Fabric Composite Seams
Authors: Tang Wenzhong , Keefe Michael
Published: June 2008

An adhesively bonded seam is a common method of joining coated fabrics in the manufacturing of inflatables. In this paper, Nylon and Polyester seams are studied both experimentally and numerically. In the numerical analyses, the seam components are described with layered models containing fabric composite layers. The in-plane and out-of-plane elastic constants of the fabric composite layers are derived using the crimp model and a stacked model respectively. An existing finite element code, ANSYS 5.7 is used to perform two-dimensional stress analyses of the seams under tension. In the analyses, a stress concentration factor is defined to evaluate the strength of the seams in comparison with their base fabric laminates. Numerical data show that Nylon seams are almost as strong as their base laminate but there is strength degradation in Polyester seams, which agrees well with test results. Finally, two structural modifications are proposed to improve the strength of the Polyester seams. The modifications are evaluated by both simulations and tests.
Investigation of Yarn Twist Propagation in Rotor Spinning
Authors: Xu BinGang , Tao XiaoMing
Published: June 2008

This paper proposed an integrated mechanical approach for yarn dynamics in rotor spinning, especially the twist propagation in the yarn forming process from fibers collected in a rotor groove to the twisted yarn at the twist stopper. Equations of dynamic equilibrium in different yarn forming regions were established, and further, expressed in terms of dimensionless variables. Then the yarn tension and twist distribution, considering the dynamic coupling effects between different regions under the steady spinning conditions, were numerically simulated, in which influences of various dimensionless parameters of rotor spinning on the yarn tension and twist distributions were discussed in details.
Evaluating the Assembly of Mirrored Large High-Density BGA Packages
Authors: Chu Joe , Chen Maosen , Chen Wyeman
Published: June 2008

The continued emphasis on higher-density (smaller) and better-performance (faster) on electronics system design makes the board (PCB layout) design become more complex and usually will challenge the DFM guidelines currently applied by the industry. For example, the design of mirrored BGAs on double-sided board, which is not recommended by current industry DFM guidelines, due to the real estate constraint. In fact, there are several successful design applying low pin count mirrored or staggered BGAs or CSPs for certain applications, such as memory modules.
Effects of Room Temperature Storage Time on the Shear Strength of PBGA Solder Balls
Authors: Lee S. W. Ricky , Tsui Yat-Kit , Hunag Xingjia , Yan Eric C. C.
Published: June 2008

This paper presents an experimental investigation on the solder ball shear strength of plastic ball grid array (PBGA) packages. The emphasis is placed on showing the effect of room temperature aging on the degradation of solder ball shear strength. The specimens under investigation are standard commercial PBGA packages with 63Sn-37Pb eutectic solder balls. The specimens are subject to various lengths (up to 72 hours) of room temperature aging after the reflow. Afterwards, ball shear tests are performed to evaluate the solder ball shear strength. The experimental results show that the solder ball shear strength may drop up to 10% within 3 days of room temperature aging. The outcome of the present study may give a general guideline for the meaningful comparison of solder ball shear strength.
Understanding the Interaction Between an Impeller and Its Inlet Guide Vanes
Authors: Hill D. Lee , Liu Zheji
Published: June 2008

Industrial turbocompressors often experience a wide range of operation. The dynamic interaction between stage components has long been recognized as an important effect that impacts both range and performance of the machine. The non-integral blade count between stationary and rotating blades has forced researchers to develop alternative numerical techniques to avoid full 360-degree sliding-mesh calculations. The relative low number of impeller blade used on a compressor, however, makes the full 360-degree simulation just as practical. This study focuses on the dynamic interaction between the inlet guide vanes and a shrouded centrifugal impeller. The primary parameter varied is the inlet guide blade count. The results between the different configurations are used to study performance implications as well as dynamic loading on the impeller itself.
Deterministic and Statistical Reliability of Surface Mount Components
Authors: Qian Zhengfang , Wu Xiaohua , Tomase Joe
Published: June 2008

This paper is to investigate both deterministic and statistical aspects of thermal reliability of solder joints of surface mount leadless components (SMLCs). The emphasis is on bridging deterministic with statistical reliability prediction. A reliable methodology has been established to predict the failure rate at accelerated life tests (ALTs) and field failed rate in terms of key statistical parameters of design, environmental condition, and material selection due to the uncertainty from the component manufacturing/assembly, temperature profile of ALTs and field environmental conditions, and material property. Analytical equations and solutions of inelastic strain range and fatigue life for simplified joint geometry have been developed from deterministic approach. They are furthermore utilized to obtain the failure functions of thermal fatigue caused by both crack initiation and crack propagation from multivariable distributions. First Order Reliability Model (FORM) has been extended by combining Taylor series in technique with central limit theorem (CLT). An important outcome is that the statistical fatigue life is a lognormal distribution in which its parameters can be analytically evaluated by the approximate method with satisfactory accuracy for small COVs (COV=mean/deviation) of random variables (RVs). Specifically, SMLCs have been investigated on inelastic strain distribution, fatigue life distribution, failure and reliability functions, and failure rate prediction based on the statistical distributions of the solder joint height, solder paste size, temperature profile, and the experimental property of the eutectic solder alloy. Moreover, the component failure under two failure modes, i.e., both crack initiation and crack propagation, has been performed to illustrate the significance of failure criteria selection and address the data collection in field. Additionally, the simulation of realistic solder joint geometry and damage-based failure processes will be also presented. The developed methodology can be directly used for the board-level reliability prediction of advanced electronic packages such as BGAs, CSPs, QFPs, and Flip-chips.
On Partially Corrugated Ducts in Heat Exchangers
Authors: Sunden Bengt
Published: June 2008

In this paper the concept of partially corrugated ducts for heat exchanger applications is discussed. The main idea is that using partially corrugated ducts instead of ducts with continuous corrugation provides a method to achieve a better balance between heat transfer enhancement and increased pressure drop penalty. The origin of the work stems from rotary regenerative heat exchangers. The present paper focuses on this matter and numerical results (based on CFD) as well as preliminary experimental heat transfer data (overall), available mass transfer results are used to support the discussions and conclusions. It is found that partially corrugated ducts might be an alternative to ducts with continuous corrugation in some cases and then present a way to control the thermal hydraulic balance. How to take advantage of the increased pressure drop is discussed briefly.
Raised Floor Computer Data Center: Effect on Rack Inlet Temperatures When High Powered Racks are Situated Amongst Lower Powered Racks
Authors: Schmidt Roger , Cruz Ethan
Published: June 2008

This paper focuses on the effect on inlet rack air temperatures when high-powered racks are situated amongst lower powered racks in a raised floor data center. Only the above floor (raised floor) flow and temperature distributions were analyzed for various flowrates exhausting from the perforated tiles and with one or two high powered racks placed at various locations amongst the lower powered racks. A Computational Fluid Dynamic (CFD) model was generated for the room with electronic equipment installed on a raised floor with particular focus on the effects on rack inlet temperatures of these high powered racks. Forty racks of data processing (DP) equipment were arranged in rows in a data center cooled by chilled air exhausting from perforated floor tiles. The chilled air was provided by four A/C units placed inside a room 12.1 m wide × 13.4 m long. Since the arrangement of the racks in the data center was symmetric only one-half of the data center was modeled. The numerical modeling was performed using a commercially available finite control volume computer code called Flotherm (Trademark of Flomerics, Inc.). The flow was modeled using the k-e turbulence model. Results are displayed to provide some guidance on the design and layout of a data center.
Fatigue Strength Evaluation for Sn-Zn-Bi Lead-Free Solder Joints
Authors: Yu Qiang , Kim Doseop , Jin Jaechul , Takahashi Yasuhiro , Shiratori Masaki
Published: June 2008

In this paper, the authors have investigated mechanical fatigue strength of Sn-Zn-Bi lead-free solder joints. The use of Sn-Zn-Bi solder is increasing for the advantage of low cost and low melting point. Therefore, it becomes important to ensure the fatigue strength of Sn-Zn-Bi solder joint. However, when the Sn-Zn-Bi solder was used as a solder material, there is serious problem that the fatigue crack is easy to generate at the interface between intermetallic compound layer and the solder matrix, and it makes the fatigue life of solder joint lower. Because the yield strength of Sn-Zn-Bi solder is high, and the difficulty of deformation causes high stress level concentrating at the corner of the interface between solder joint and substrate/package. It seems that the crack become easy to generate at the interface between intermetallic compound layer and solder matrix by this high stress concentration. The authors have found if Sn-Zn-Bi is used with another Pb-free solder material, a kind of composite structure can be built during the reflowing processes. In this study, the mechanical fatigue strength of this kind of Sn-Zn-Bi solder joint was studied. Based upon the results of mechanical shear fatigue test and FEM (Finite Element Method) analysis, it was found that if SnZn-Bi was used as reflow solder with Sn-Ag-Cu ball, the CSP solder joints are as reliable as thc pure Sn-Ag-Cu CSP. This is because Sn-Zn-Bi solder paste and Sn-Ag-Cu solder ball did not melt together completely and formed two-layer structure, and this two-layer structure reduces the stress concentration at the joint corners, and prevents successfully the occurrence of the interface cracks. As a result the fatigue life of Sn-Zn-Bi/Sn-Ag-Cu CSP is equivalent to that of Sn-Ag-Cu joints.
Examining pacing profiles in elite female road cyclists using exposure variation analysis
Authors: Abbiss C R , Straker L , Quod M J , Martin D T , Laursen P B
Published: June 2008

Objective

In this study, the amplitude and time distribution of power output in a variety of competitive cycling events through the use of a new mathematical analysis was examined: exposure variation analysis (EVA).

Design

Descriptive field study.

Setting

Various professional road cycling events, including; a 5-day—eight-stage tour race, a 1-day World Cup event and the Australian National Individual Time Trial Championships.

Participants

9 elite female cyclists (mean (SD), mass = 57.8 (3.4) kg, height = 167.3 (2.8) cm, Vo2peak = 63.2 (5.2) ml kg−1min−1).

Interventions

None.

Main outcome measurements

The variation in power output and the quantification of the total time and acute time spent at various exercise intensities during competitive professional cycling were examined. Predefined levels of exercise intensity that elicited first ventilation threshold, second ventilation threshold and maximal aerobic power were determined from a graded exercise test performed before the events and compared with power output during each event.

Results

EVA exposed that power output during the time trial was highly variable (EVASD= 2.81 (0.33)) but more evenly distributed than the circuit/criterium (4.23 (0.31)) and road race events (4.81 (0.96)).

Conclusion

EVA may be useful for illustrating variations in the amplitude and time distribution of power output during cycling events. The specific race format influenced not only the overall time spent in various power bands, but also the acute time spent at these exercise intensities.
Effect of continuous positive airway pressure therapy on hypothalamic-pituitary-adrenal axis function and 24-h blood pressure profile in obese men with obstructive sleep apnea syndrome
Authors: Carneiro Gláucia , Togeiro Sônia Maria , Hayashi Lílian F. , Ribeiro-Filho Fernando Flexa , Ribeiro Artur Beltrame , Tufik Sérgio , Zanella Maria Teresa
Published: June 2008

Obstructive sleep apnea syndrome (OSAS) increases the risk of cardiovascular events. Sympathetic nervous system and hypothalamic-pituitary-adrenal (HPA) axis activation may be the mechanism of this relationship. The aim of this study was to evaluate HPA axis and ambulatory blood pressure monitoring in obese men with and without OSAS and to determine whether nasal continuous positive airway pressure therapy (nCPAP) influenced responses. Twenty-four-hour ambulatory blood pressure monitoring and overnight cortisol suppression test with 0.25 mg of dexamethasone were performed in 16 obese men with OSAS and 13 obese men controls. Nine men with severe apnea were reevaluated 3 mo after nCPAP therapy. Body mass index and blood pressure of OSAS patients and obese controls were similar. In OSAS patients, the percentage of fall in systolic blood pressure at night ( P = 0.027) and salivary cortisol suppression postdexamethasone ( P = 0.038) were lower, whereas heart rate ( P = 0.022) was higher compared with obese controls. After nCPAP therapy, patients showed a reduction in heart rate ( P = 0.036) and a greater cortisol suppression after dexamethasone ( P = 0.001). No difference in arterial blood pressure ( P = 0.183) was observed after 3 mo of nCPAP therapy. Improvement in cortisol suppression was positively correlated with an improvement in apnea-hypopnea index during nCPAP therapy ( r = 0.799, P = 0.010). In conclusion, men with OSAS present increased postdexamethasone cortisol levels and heart rate, which were recovered by nCPAP.
Insulin acts at different CNS sites to decrease acute sucrose intake and sucrose self-administration in rats
Authors: Figlewicz Dianne P. , Bennett Jennifer L. , Aliakbari Sepideh , Zavosh Aryana , Sipols Alfred J.
Published: June 2008

Findings from our laboratory and others have demonstrated that the hormone insulin has chronic effects within the CNS to regulate energy homeostasis and to decrease brain reward function. In this study, we compared the acute action of insulin to decrease intake of a palatable food in two different behavioral tasks—progressive ratios sucrose self-administration and mu opioid-stimulated sucrose feeding—when administered into several insulin-receptive sites of the CNS. We tested insulin efficacy within the medial hypothalamic arcuate (ARC) and paraventricular (PVN) nuclei, the nucleus accumbens, and the ventral tegmental area. Administration of insulin at a dose that has no chronic effect on body weight (5 mU) into the ARC significantly suppressed sucrose self-administration (75 ± 5% of paired control). However, although the mu opioid DAMGO, [d-Ala2,N-MePhe4,Gly5-ol]-enkephalin acetate salt, stimulated sucrose intake at all four CNS sites, the ventral tegmental area was the only sensitive site for a direct effect of insulin to antagonize acute (60 min) mu opioid-stimulated sucrose feeding: sucrose intake was 53 ± 8% of DAMGO-induced feeding, when insulin was coadministered with DAMGO. These findings demonstrate that free feeding of sucrose, and motivated work for sucrose, can be modulated within unique sites of the CNS reward circuitry. Further, they support the interpretation that adiposity signals, such as insulin, can decrease different aspects of ingestion of a palatable food, such as sucrose, in an anatomically specific manner.
Determinants of Laser-Evoked EEG Responses: Pain Perception or Stimulus Saliency?
Authors: Iannetti G. D. , Hughes N. P. , Lee M. C. , Mouraux A.
Published: June 2008

Although laser-evoked electroencephalographic (EEG) responses are increasingly used to investigate nociceptive pathways, their functional significance remains unclear. The reproducible observation of a robust correlation between the intensity of pain perception and the magnitude of the laser-evoked N1, N2, and P2 responses has led some investigators to consider these responses a direct correlate of the neural activity responsible for pain intensity coding in the human cortex. Here, we provide compelling evidence to the contrary. By delivering trains of three identical laser pulses at four different energies, we explored the modulation exerted by the temporal expectancy of the stimulus on the relationship between intensity of pain perception and magnitude of the following laser-evoked brain responses: the phase-locked N1, N2, and P2 waves, and the non-phase-locked laser-induced synchronization (ERS) and desynchronization (ERD). We showed that increasing the temporal expectancy of the stimulus through stimulus repetition at a constant interstimulus interval 1) significantly reduces the magnitudes of the laser-evoked N1, N2, P2, and ERS; and 2) disrupts the relationship between the intensity of pain perception and the magnitude of these responses. Taken together, our results indicate that laser-evoked EEG responses are not determined by the perception of pain per se, but are mainly determined by the saliency of the eliciting nociceptive stimulus (i.e., its ability to capture attention). Therefore laser-evoked EEG responses represent an indirect readout of the function of the nociceptive system.
Localization of genetic loci controlling hydronephrosis in the Brown Norway rat and its association with hematuria
Authors: Kota Lalitha , Schulz Herbert , Falak Samreen , Hübner Norbert , Osborne-Pellegrin Mary
Published: June 2008

The aim of this study was to investigate the genetic basis of congenital hydronephrosis (HN), a poorly defined pathological entity, with a rat model. The Brown Norway (BN) strain spontaneously presents a high incidence of apparently asymptomatic HN, whereas the LOU strain does not. A backcross was established between these two strains [BN × (BN × LOU)] and a genomewide scan was performed with 193 microsatellite markers on 121 males and 118 females of this population, which had been phenotyped and scored for HN severity (defined as degree of renal pelvic dilation), followed by linkage analysis with Mapmaker/QTL software. Bilateral HN score was significantly linked to a locus on chromosome 6 ( Z scores 4.4 and 4.8 for all rats and for females, respectively). Suggestive loci were identified on chromosomes 2 (for only right-sided HN) and 4. This is the first study in rats to identify genetic loci for HN. Three candidate genes present in these loci were sequenced and insertions detected in Id2 and Agtr1b genes in BN, which did not, however, lead to modified expression as measured by quantitative PCR. Production of a congenic line for part of the chromosome 6 locus confirmed its involvement in HN, but the phenotype was mild. Evidence of hematuria was observed in 9.6% of the backcross rats, mostly males and only in kidneys with HN, but not necessarily in the most severely affected. Hematuria also occurs in the BN colony used here, where it is due to papilloma-like lesions involving pelvic epithelial proliferation, but not in the LOU rat.
SOX17 directly activatesZfp202transcription during in vitro endoderm differentiation
Authors: Patterson Ethan S. , Addis Russell C. , Shamblott Michael J. , Gearhart John D.
Published: June 2008

SOX17 is a SRY-related high-mobility group (HMG) box transcription factor that is necessary for endoderm formation in multiple species. Despite its essential function during endoderm formation and differentiation, few direct targets of SOX17 are known. To identify targets of SOX17, we isolated SOX17 binding sites with a chromatin immunoprecipitation (ChIP)-cloning screen. SOX17-ChIP identified zinc finger protein 202 ( Zfp202) as a direct target of SOX17 during endoderm differentiation of F9 embryonal carcinoma cells. A sequence in the first intron of Zfp202 activated transcription in differentiated F9 cells, and overexpression of Sox17 increased the transcriptional activity of this sequence. SOX17 binds to a site within this sequence in electrophoretic mobility shift assays, and mutation of this site decreases the transcriptional activation. Zfp202 is induced concomitantly with Sox17 during endoderm differentiation of F9 cells. We also show that ZFP202 represses Hnf4a, which has been reported for the human ortholog ZNF202. Identifying targets of SOX17 will help to elucidate the molecular basis of endoderm differentiation and may provide a better understanding of the role of endoderm in patterning the other germ layers.
The Recidivism Patterns of Previously Deported Aliens Released From a Local Jail: Are They High-Risk Offenders?
Authors: Hickman Laura J. , Suttorp Marika J.
Published: June 2008

Previously deported aliens are a group about which numerous claims are made but very few facts are known. Using data on male deportable aliens released from a local jail, the study sought to test the ubiquitous claim that they pose a high risk of recidivism. Using multiple measures of recidivism and propensity score weighting to account for preexisting group differences, the authors find consistent support for the assertion that previously deported aliens are a high recidivism risk. Relative to similarly situated deportable aliens with no record of deportation, previously deported aliens are more likely to be rearrested, to be rearrested more quickly, and to be rearrested more frequently in a 1-year follow-up period.
Elder Physical Abuse and Failure to Report Cases
Authors: Payne Brian K.
Published: June 2008

Treated initially as a social problem, elder abuse has only recently been criminalized. The criminalization of elder abuse involves penalizing offenders for actively abusing offenders as well as for violating mandatory reporting laws. Mandatory reporting laws exist to encourage professionals to report suspected cases of elder abuse. In this study, attention is given to the way that failure to report elder abuse cases are adjudicated in comparison to elder physical abuse cases. Content analysis was performed on a sample of case descriptions of elder physical abuse cases and failure to report cases. Results suggest that mandatory reporting offenses are adjudicated slightly differently than physical abuse cases, and the dynamics surrounding the two offense types vary as well. Implications including the need for broader penalties and better training of human services professionals are suggested.
Functional Analysis and Treatment of Nail Biting
Authors: Dufrene Brad A. , Steuart Watson T. , Kazmerski Jennifer S.
Published: June 2008

This study applied functional analysis methodology to nail biting exhibited by a 24-year-old female graduate student. Results from the brief functional analysis indicated variability in nail biting across assessment conditions. Functional analysis data were then used to guide treatment development and implementation. Treatment included a simplified habit reversal package that was modified based on results of the functional analysis. Following treatment implementation, nail biting decreased as evidenced by consistent nail growth and participant self-recorded data. Results are discussed in terms of treatment utility of functional analysis methodology for novel populations and response topographies.
Spousal Violence in Bangladesh as Reported by Men
Authors: Johnson Kiersten Blair , Das Maitreyi Bordia
Published: June 2008

To study risk factors for perpetration of spousal violence among men in Bangladesh, self-reported Demographic and Health Surveys data from 2,780 married men using bivariate and multivariate techniques are analyzed. Of the respondents, 74% report having ever been violent toward their wives; 37% report violence in the past year. Nonnormative behaviors increase the risk for violence: Men who marry more than once, men who use drugs, and men who are unfaithful to their wives are all significantly more likely to report violence against their spouses. Egalitarian attitudes toward women do not decrease the risk for violence. However, attitudes explicitly about wife-beating are the strongest predictor of violence: Men who believe wife-beating is acceptable are more than 4 times as likely to report recent violence against their wives. While men's self-reports of spousal violence indicate that wife-beating is prevalent in Bangladesh, the results indicate opportunities for programmatic intervention.
Guided Team Self-Correction
Authors: Smith-Jentsch Kimberly A. , Cannon-Bowers Janis A. , Tannenbaum Scott I. , Salas Eduardo
Published: June 2008

This research investigated the effects of guided team self-correction using an empirically derived expert model of teamwork as the organizing framework. First, the authors describe the process used to define this model. Second, they report findings from two studies in which the expert model was used to structure the process of guided team self-correction. Participants were U.S. Navy command and control teams (25 in Study 1, 13 in Study 2). Results indicated that teams debriefed using the expert model-driven guided team self-correction approach developed more accurate mental models of teamwork (Study 1) and demonstrated greater teamwork processes and more effective outcomes (Study 2) than did teams debriefed using a less participative and chronologically organized approach that is more typical for these teams.
Interdisciplinarity as Teamwork
Authors: Fiore Stephen M.
Published: June 2008

This essay discusses interdisciplinary research in the context of science policy and the practice of science. Comparisons between interdisciplinary research and other forms of cross-disciplinary research are made, and a brief discussion of the development of the concept of interdisciplinarity is provided. The overarching thesis of this essay is that interdisciplinary research is team research, that is, research conducted by a team. This notion is developed via recent policy discussions of team science and the need to understand interdisciplinary research in action. The author shows how it may be possible to consider the implementation of principles from teamwork and team training to improve interdisciplinary research and the practice of team science.
Learning and Knowledge Sharing in Virtual Communities of Practice: Motivators, Barriers, and Enablers
Authors: Ardichvili Alexandre
Published: June 2008

The problem and the solution . Virtual (online) communities of practice (VCoPs; when community members share and cocreate knowledge in online discussions and other forms of knowledge exchange) are increasingly viewed as important vehicles of collective learning in the workplace. Currently, factors leading to successful online knowledge sharing are not well understood. This article is based on an extensive review of online learning, knowledge management, and online communication literature, and proposes a framework for understanding motivators, barriers, and enablers for successful online knowledge sharing and learning. The framework includes key motivational factors, such as utilitarian considerations, value-based considerations, and sense of community and belonging; barriers to online knowledge sharing, including interpersonal factors, procedural and/or use of technology-related factors, and cultural norms; and enablers of VCoP knowledge sharing, including supportive organizational culture, presence of personal knowledge-based trust, and availability of adequate tools. The article concludes with specific recommendations for promoting and supporting vibrant and productive VCoPs.
Essential role of nuclear factor-κB for NADPH oxidase activity in normal and anhidrotic ectodermal dysplasia leukocytes
Authors: Luengo-Blanco Marcos , Prando Carolina , Bustamante Jacinta , Aragão-Filho Walmir Cutrim , Pereira Paulo Vitor Soeiro , Rehder Jussara , Padden Carolyn , Casanova Jean-Laurent , Newburger Peter E. , Condino-Neto Antonio
Published: June 2008

This work investigated the functional role of nuclear factor–κB (NF-κB) in respiratory burst activity and in expression of the human phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase genes CYBB, CYBA, NCF1, and NCF2. U937 cells with a stably transfected repressor of NF-κB (IκBα-S32A/S36A) demonstrated significantly lower superoxide release and lower CYBB and NCF1 gene expression compared with control U937 cells. We further tested Epstein-Barr virus (EBV)-transformed B cells from patients with anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID), an inherited disorder of NF-κB function. Superoxide release and CYBB gene expression by EDA-ID cells were significantly decreased compared with healthy cells and similar to cells from patients with X-linked chronic granulomatous disease (X910 CGD). NCF1 gene expression in EDA-ID S32I cells was decreased compared with healthy control cells and similar to that in autosomal recessive (A470) CGD cells. Gel shift assays demonstrated loss of recombinant human p50 binding to a NF-κB site 5′ to the CYBB gene in U937 cells treated with NF-κB inhibitors, repressor-transfected U937 cells, and EDA-ID patients' cells. Zymosan phagocytosis was not affected by transfection of U937 cells with the NF-κB repressor. These studies show that NF-κB is necessary for CYBB and NCF1 gene expression and activation of the phagocyte NADPH oxidase in this model system.
Id2 intrinsically regulates lymphoid and erythroid development via interaction with different target proteins
Authors: Ji Ming , Li Huajie , Suh Hyung Chan , Klarmann Kimberly D. , Yokota Yoshifumi , Keller Jonathan R.
Published: June 2008

Inhibitors of DNA binding (Id) family members are key regulators of cellular differentiation and proliferation. These activities are related to the ability of Id proteins to antagonize E proteins and other transcription factors. As negative regulators of E proteins, Id proteins have been implicated in lymphocyte development. Overexpression of Id1, Id2, or Id3 has similar effects on lymphocyte development. However, which Id protein plays a physiologic role during lymphocyte development is not clear. By analyzing Id2 knock-out mice and retroviral transduced hematopoietic progenitors, we demonstrated that Id2 is an intrinsic negative regulator of B-cell development. Hematopoietic progenitor cells overexpressing Id2 did not reconstitute B-cell development in vivo, which resembled the phenotype of E2A null mice. The B-cell population in bone marrow was significantly expanded in Id2 knock-out mice compared with their wild-type littermates. Knock-down of Id2 by shRNA in hematopoietic progenitor cells promoted B-cell differentiation and induced the expression of B-cell lineage–specific genes. These data identified Id2 as a physiologically relevant regulator of E2A during B lymphopoiesis. Furthermore, we identified a novel Id2 function in erythroid development. Overexpression of Id2 enhanced erythroid development, and decreased level of Id2 impaired normal erythroid development. Id2 regulation of erythroid development is mediated via interacting with transcription factor PU.1 and modulating PU.1 and GATA-1 activities. We conclude that Id2 regulates lymphoid and erythroid development via interaction with different target proteins.
GMDD: a database of GMO detection methods
Authors: Dong Wei , Yang Litao , Shen Kailin , Kim Banghyun , Kleter Gijs A , Marvin Hans JP , Guo Rong , Liang Wanqi , Zhang Dabing
Published: June 2008

Background

Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed.

Results

GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the information on endogenous genes, certified reference materials, reference molecules, and the validation status of developed methods is included in this database. Furthermore, registered users can also submit new detection methods and sequences to this database, and the newly submitted information will be released soon after being checked.

Conclusion

GMDD contains comprehensive information of GMO detection methods. The database will make the GMOs analysis much easier.
A randomised trial of a 5 week, manual based, self-management programme for hypertension delivered in a cardiac patient club in Shanghai
Authors: Xue Feng , Yao Wen , Lewin Robert J
Published: June 2008

Background

In Shanghai there are 1.2 million people with hypertension, many of whom have difficulty in affording medical treatment. Community based, anti-hypertensive clubs have been created to provide health education but education alone is often ineffective. Lifestyle change programmes have shown some potential for reducing blood pressure but in previous trials have required specialist staff and extensive contact. We have previously demonstrated that self-management programmes delivered by health professionals, such as a nurse who has had short training in self-management techniques can change health behaviour and reduce symptoms. This study was designed to evaluate the benefits of a simple, cognitive-behavioural, self-management programme for hypertension based around a hypertension manual and delivered in the setting of a community anti-hypertensive club in Shanghai.

Method

The method was a pragmatic randomised controlled trial with an intention-to-treat analysis. Adult patients with mild-to-moderate primary hypertension, waiting to join a neighbourhood anti-hypertension club, were randomised to the self-management programme or to an information only control procedure. They attended the group treatment sessions on 4 occasions over 5 weeks for education combined with goal setting for lifestyle change and an introduction to exercise. The main outcome measures were: changes in blood pressure; blood total cholesterol; diet; activity level and health related quality of life 1 month and 4 months after the end of treatment.

Results

A total of 140 adults with mild-to-moderate primary hypertension took part. All of the main outcomes showed beneficial changes. Four months after the end of treatment the mean blood pressure differences between groups were systolic 10.15 mm Hg (P < 0.001, 95% CI 7.25–13.05), and diastolic 8.29 mmHg (P < 0.001, 95% CI 6.71–9.88). Patients in the intervention group also had significantly reduced weight, lowered blood total cholesterol, increased physical activity and improved quality of life.

Conclusion

Patients with mild-to-moderate primary hypertension attending a 5 week, group and manual based, cognitive-behavioural self-management programme, delivered through a voluntary club in Shanghai experienced a significant reduction in blood pressure.

Trial registration

Current Controlled Trials ISRCTN73114566