cssi/SciSciGPT-SciSciNet huggingface dataset:
Cold Pre-Compression Treatment of Gas Diffusion Electrode for PEM Fuel Cells

In a PEM fuel cell, it has been shown that the compression under the land area is the main reason for the observed higher performance than that under channel areas. If the area under the channel can also benefit from such a compression the overall performance of the cell will increase. Since the areas under the channel are not directly compressed in an assembled fuel cell, it is the objective of this study to determine if a cold pre-compression treatment of the gas diffusion electrode (GDE) may have a significant positive effect on the overall performance of the cell. First, the GDE is cold pre-compressed to a level similar to the compression that would be experienced by the land areas in an assembled fuel cell. Then the pre-compressed GDE is assembled in a regular test fuel cell and the performances under various operating conditions are studied. Finally, the cell performance results are compared with the results obtained from a fuel cell with a regular GDE. The experimental results show that cold pre-compress of the GDE has significantly improved the overall performance of the fuel cell. Further experiments have also been conducted with five different levels of cold pre-compression to determine if there exists an optimal compression and its value if it exists. The experimental results show that the performance of the fuel cell first increases with the level of cold pre-compression, reaching a maximum and then decreases with the level of compression. These results clearly indicate that there indeed exists an optimal level of compression. Further studies using both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) have further corroborated the cell performance findings as well as the underlying mechanism. The results of EIS indicate that the ohmic resistance is hardly affected by the cold pre-compression, while the charge transfer resistance is significantly affected, especially in high current density region. The CV results show that the electro-chemical area (ECA) is higher with the cold pre-compressed GDE and there is an optimal compression that results in the maximum ECA. Therefore, the experimental results have shown that (a) the cold pre-compression treatment of the GDE is an effective and simple technique to increase PEM fuel cell performances; (b) there exists an optimal compression level at which the cell reaches its maximum performance; and (c) the increased performance is due to the increase of ECA resulting from the cold pre-compression treatment.Copyright © 2011 by ASME
Encapsulation of a porcine dermis pubovaginal sling.

Porcine dermis is one of several tissues available for use as a graft in pubovaginal sling surgery. Short-term success rates using this material approach those of autologous fascia, and no adverse events relating directly to the material itself have yet been described. Porcine dermis reportedly functions as a scaffold for ingrowth of the native tissue, and histological animal studies have confirmed prompt remodeling and neovascularization following implantation. However, to our knowledge no studies have investigated the eventual fate of the material in humans. We report a case of removal of a porcine dermis pubovaginal sling. CASE REPORT A 42-year-old female presented in complete urinary retention 4 months after undergoing porcine dermis pubovaginal slingplasty. According to records she was unable to urinate in the immediate postoperative period, and required indwelling and intermittent catheterization after failing several voiding trials. The patient was catheterizing up to 5 times per day following surgery. Physical examination revealed a fixed urethra and a small cystocele. There was a ridging effect at the bladder neck, which was confirmed with cystoscopy. Videourodynamics demonstrated an absence of unstable detrusor contractions and was suggestive of outlet obstruction. At urethrolysis the intact porcine sling was found encased in a well-defined capsule (fig. 1). The sling was easily removed in toto and the ridging effect resolved. The patient voided immediately after surgery and continues to empty efficiently 3 months after surgery. She remains continent. Pathological analysis showed a completely intact acellular porcine dermis sling without evidence of human tissue proliferation (fig. 2). Analysis of the capsule revealed benign fibrous tissue with evidence of chronic inflammation.
Angiotensin II rapidly modulates the renal peripheral benzodiazepine receptor.

The effects of acute exposure to angiotensin II (AII) on the renal peripheral benzodiazepine receptor were studied in rats. As little as 37.5 micrograms of AII injected s.c. over an 80 min period caused immediate reductions in [3H]Ro5-4864 binding. Scatchard analysis revealed that the reduction in [3H]Ro5-4864 binding induced by AII was due to a drop in receptor density or Bmax. The influence of AII on the peripheral benzodiazepine receptor is similar to that of stress.
ARGININE THERAPY OF ARGININOSUCCINASE DEFICIENCY

Abstract Argininosuccinic acid (A.S.A.) contains the two waste nitrogen atoms later excreted in urea in healthy people, and it has a renal clearance similar to the glomerular filtration-rate. Therefore, argininosuccinic acid might provide a vehicle for the excretion of waste nitrogen in patients with argininosuccinase deficiency, providing that stoichiometric amounts of ornithine are available. When two infants with no, or very little, erythrocyte argininosuccinase activity who were in neonatal hyperammonaemic coma were treated with supplementary arginine (4-5 mmol/kg/day) plasma ammonium, glutamine, and alanine concentrations became normal. One infant grew and developed normally during the first month of life on a protein intake of 2 g/kg/day. The other infant had sustained lethal brain damage before arginine therapy was tried and she died aged 17 days. Arginine supplementation may be effective therapy for argininosuccinase deficiency because it promotes A.S.A. synthesis and hence excretion of waste nitrogen. The effects of high plasma-A.S.A. concentrations are unknown.
Radiology Physician Extenders and Their Perspective in Their Own Words

Physician assistants have been previously studied to evaluate their satisfaction with their vocation. A recent evaluation of physician assistants demonstrated common themes that indicated job satisfaction and dissatisfaction. Provider satisfaction increases the likelihood of provider retention in any practice. Physician extenders provide an enlarging portion of radiology services. Understanding the motivations, expectations, and needs of this group of midlevel care providers as perceived by these providers will allow radiology practices to better address these issues and retain these needed practitioners. Previous evaluations have been performed on the physician assistant community at large rather than on radiology extenders, a relatively new position. Therefore, the authors sought to assess the factors that influence vocational satisfaction in radiology extenders at their institution to identify issues specific to these providers. The use of qualitative data analysis allowed the physician extenders to speak for themselves.
Degradations in the electrical and structural characteristics of Schottky diodes and ohmic contacts to GaAs due to thermal aging

Abstract The reliability of GaAs microwave devices is directly related to the integrity of Schottky and ohmic contacts for Schottky barrier devices and metal/semiconductor field effect transistor devices. The interface analysis of these device structures using surface analysis techniques has become extremely important in the study of the degradation of these devices. The research reported here focuses on three different metallic systems, namely Au/In, Au-12 wt.% Ge and Ni/AuGe, for both Schottky and ohmic contacts. The three metallic systems were evaporated onto 〈100;〉- oriented GaAs substrates ( N D =3×10 17 cm -3 ) in an ultrahigh vacuum system. These samples were thermally aged by keeping them at 150°C for 500h. Current-voltage and capacitance-voltage measurements were made on as-deposited and thermally aged samples. The ideality factor decreased in all the samples. There was an apparent large increase in barrier height in AuGe/GaAs and Ni/AuGe/GaAs Schottky diodes. There was an insignificant change in the contact resistivity of ohmic contacts after thermal aging. The changes in the electrical characteristics of these device structures are explained on the basis of the formation of an oxide layer after thermal aging. A comparison of the Auger depth profiles of the as-deposited and the thermally aged samples substantiates the electrical observations. However, Au/In/GaAs Schottky diodes do not show the existence of an oxide layer at the interface. The out-diffusion of indium to the surface might have removed the oxygen from the interface to result in an Au-GaAs interface in the thermally aged sample. A slight increase in the barrier height of this sample is due to the Au-GaAs interface rather than the In-GaAs interface.
Detection and classification of individual airborne microparticles using laser ablation mass spectroscopy and multivariate analysis

We are developing a method for the real-time analysis of airborne microparticles based on laser-ablation mass spectroscopy. Airborne particles enter an ion trap mass spectrometer through a differentially pumped inlet, are detected by light scattered from two continuous-wave (CW) laser beams, and sampled by a 10-ns excimer laser pulse at 308 nm as they pass through the center of the ion trap electrodes. Following the laser pulse the stored ions are mass analyzed with the use of conventional ion trap methods. In this work thousands of positive and negative ion spectra were collected for 18 different samples: six species of bacteria, six types of pollen, and six types of particulate matter. The data were averaged and analyzed with the use of the multivariate patch algorithm (MPA), a variant of traditional multivariate analysis. The MPA successfully differentiated between all of the average positive ion spectra and 17 of the 18 average negative ion spectra. In addition, when the average positive and negative spectra were combined the MPA correctly identified all 18 types of particles. Finally, the MPA is also able to identify the components of computer-synthesized mixtures of spectra from the samples studied. These results demonstrate the feasibility of using a less-specific real-time analytical monitoring technique to detect substantial changes in the background concentration of environmental organisms, indicating that a more selective assay should be initiated. © 2000 John Wiley & Sons, Inc. Field Analyt Chem Technol 4: 31–42, 2000
Spin-Orbit Coupling in the Alpha-Model of Light Nuclei

If light nuclei are approximated by the alpha-model, with the particles localized in clusters of four (or less), the particle with uncompensated spin is accelerated by the relatively weak attraction of alphas, or by the difference of the attractions of two clusters. Then the Thomas relativistic term is not in general larger than the Larmor magnetic term in the spin-orbit coupling in contrast to the result of the central model, wherein the acceleration may be attributed to unsaturated forces toward one center. The relative magnitudes of these terms are estimated for the alpha-model of ${\mathrm{Li}}^{7}$ and ${\mathrm{C}}^{13}$, two of the few nuclei to which it is here considered that the model might apply. The magnetic moment consistent with the Larmor-Thomas coupling in the alpha-model of ${\mathrm{B}}^{11}$ is found to be considerably larger than the experimental value. The quadrupole moment of the deuteron implies a spin-orbit coupling arising directly from angle-dependent nuclear forces. The appropriate "spin-orbit-spin" angle dependence suggested by the meson theory causes no first-order coupling in the alpha-model of ${\mathrm{Li}}^{7}$, however, and a rough estimate of the second-order doublet splitting shows that it may be considerably smaller than that due to the Larmor and Thomas terms.
Demyelination and remyelination in anatomically distinct regions of the corpus callosum following cuprizone intoxication.

Multiple sclerosis is a chronic demyelinating disease of the central nervous system. Spontaneous remyelination during early disease stages is thought to preserve and partially restore function. However, this process ceases in later stages despite the presence of pre-oligodendrocytes. Cuprizone-induced demyelination is a useful model with which to study the remyelination process. Previous studies have demonstrated heterogeneities in demyelination in individual animals. Here we investigated regional differences in demyelination and remyelination within the corpus callosum. C57BL/6 mice were fed 0.2% cuprizone for 5 weeks to induce demyelination. Remyelination was examined 2–5 weeks after cuprizone withdrawal. Immunohistochemistry and electron microscopy were used to quantify regional differences in demyelination, gliosis, and remyelination. We found that, while demyelination was limited in the rostral region of corpus callosum, nearly complete demyelination occurred in the caudal callosum, beginning at approximately −0.5 mm from bregma. Astrogliosis and microgliosis were correlated with demyelination and differed between the rostral and caudal callosal structures. Remyelination upon cessation of cuprizone ensued at different rates with splenium remyelinating faster than dorsal hippocampal commissure. Our data show anatomical differences of cuprizone-induced demyelination and remyelination in the corpus callosum and the importance of examining specific callosal regions in myelin repair studies using this model.
Laminar forced convection heat transfer in microcapsulated phase change material suspensions

An experimental study using a suspension of n-eicosane microcapsules in water was conducted in order to evaluate the heat transfer characteristics of phase change material suspensions. Experiments were done for laminar, hydrodynamically fully developed flows in a circular duct with a constant wall heat flux. The temperature of the suspension entering the test section was maintained at or below the melting point of the phase change material. The primary parameters in the study were the bulk Stefan number and the volumetric concentration. In addition, a few experiments were conducted to evaluate the effect of particle diameter and degree of homogeneity of the suspension. The heat fluxes chosen for the experiments were typical of low temperature applications (below 60°C). Results show that use of phase change material suspensions can reduce the rise in wall temperature by up to 50% as compared to a single phase fluid for the same non-dimensional parameters. The most dominant parameter influencing the heat transfer was found to be the bulk Stefan number. The effect of concentration was found to be insignificant by itself, though its influence is felt indirectly through the bulk Stefan number. An increase in particle diameter by a factor of 2.5 was found to further reduce the wall temperature rise by 15%. The degree of homogeneity of the suspension had no observable effect on the wall temperatures.
Deuterium permeation through oxidized fecralloy

Abstract Deuterium permeabilities were determined for a series of 19 samples of Fecralloy A (an iron-chromium-aluminum alloy) oxidized in air at temperatures from 900°C to 1150°C for times from 4 hours to 192 hours. Permeability reductions of 10 to 500 times were observed with practically all of the samples falling in the 10 to 100 range. By depositing palladium over some of the oxidized samples it was determined that a significant part of the observed permeability reduction was due to surface effects related to defects in the oxide and the rest was due to protection of a large fraction of the surface by an essentially impermeable layer of aluminum oxide.
Marital and Family Satisfaction as a Function of Work–Family Demands and Community Resources Individual- and Couple-Level Analyses

This study uses individual- and couple-level analyses to examine the influence of work–family demands and community resources on marital and family satisfaction within a sample of dual-earner parents with dependent children (N = 260 couples, 520 individuals). Total couple work hours were strongly negatively associated with marital satisfaction for both fathers and mothers. Work hours may be best studied as a couple-level demand, and working shorter combined hours, if possible, may be a central component of a broader adaptive strategy. Negative work-to-family spillover was negatively associated with parents’ family satisfaction, but for mothers this relationship was mediated by negative affect and (marginally) by couple disagreements. Finally, fathers’ neighborhood friends emerged as an important resource for both fathers and mothers, suggesting gender differences in the role of community in the work–family interface and highlighting the need for further research of community-level resources.
The Concept of Black Power: Its Continued Relevance:

Black studies as an institutional discipline emerged out of the many sacrifices of passionate, youthful advocates of Black power in the mid- to late 1960s. Today, the term Black power seems almost ...
The Many Faces of Elite Power in the "System of 1896"

We formalize and test arguments originating with Schattschneider and Burnham about elite control of the governing process in the “system of 1896.” To do so, we draw upon classic elite theory and contemporary public policy theory to specify the particular ways elite power might have operated and to deduce a series of hypotheses about such power at various stages in the policy process. Our empirical tests of the resultant propositions—for the controversy over direct democracy reform adoptions in individual American states—offer notable evidence for elite influence over the active agenda status of direct democracy proposals, as well as over the adoption, scope of adoption, and speediness of adoption of such reforms.
The ability of positive transcription elongation factor B to transactivate human immunodeficiency virus transcription depends on a functional kinase domain, cyclin T1, and Tat.

The transcriptional transactivator Tat from human immunodeficiency viruses (HIV-1 and HIV-2) and simian immunodeficiency virus is a highly conserved and unique transcriptional activator in that it binds to RNA rather than to DNA to increase rates of elongation rather than initiation of transcription (17). Its RNA target, the transactivation response element (TAR), forms a stable stem-loop at the 5′ end of all viral transcripts (17). Tat is absolutely essential for viral replication and has been a major focus of research on new anti-HIV therapeutic strategies (10). For example, dominant negative Tat proteins (5), TAR decoys (19), new phenothiazines (16), and kinase inhibitors (22) have all been demonstrated to decrease the ability of Tat to function on the viral promoter, the 5′ long terminal repeat (HIV-1 LTR). Tat binds to TAR via its RNA-binding domain in the C-terminal half of the protein (17). Additionally, Tat exists in multiprotein complexes in cells. One of these comprises the RNA polymerase II (RNAPII) holoenzyme (7, 11), which contains up to 100 polypeptides and can initiate transcription from promoters in the presence of general transcription factors TFIID and TFIIB (7). In the holoenzyme complex, Tat interacts with TFIIH and activates CDK7, a cyclin H-dependent serine/threonine kinase that is known to phosphorylate the C-terminal domain (CTD) of RNAPII (7, 12, 27, 35). The conversion from a nonphosphorylated CTD (RNAPIIa) to a phosphorylated CTD (RNAPIIo) is a hallmark of the transition from initiation to elongation of transcription (26). Tat also exists in a second complex, which contains CDK9, which, together with cyclin T1, hyperphosphorylates the CTD (22, 34, 38). Transcriptionally active CDK9 is a component of the positive transcription elongation factor b (P-TEFb), which was defined first in in vitro transcription systems from Drosophila melanogaster (23). Cyclin T1 also binds to Tat, increases the affinity of Tat for TAR in vitro, and rescues the block to Tat transactivation in rodent cells (33). Tat-TFIIH and Tat–P-TEFb complexes might function independently and sequentially, such that the activation of CDK7 leads to promoter clearance and the recruitment of CDK9 for efficient elongation, or dependently, such that CDK7 directly or indirectly modifies the activity of CDK9 or vice versa. Given these data, several critical questions remained. Which of these Tat complexes can interact with TAR, and which kinase can function via RNA to transactivate the HIV-1 LTR? In this study, we demonstrate that CDK9 can function via RNA but only when its kinase domain is intact. Cyclin T1 is also required for the function of CDK9. Finally, we demonstrate that the Tat–P-TEFb complex interacts specifically with TAR in a manner that depends on the 5′ bulge and central loop of TAR. We conclude that Tat–P-TEFb complexes are functional at TAR and suggest that Tat-TFIIH complexes act at an earlier step, such as promoter clearance.
Recombinant Factor VII Is Associated With Worse Survival in Complex Cardiac Surgical Patients

Background Recombinant activated factor VII (rFVIIa) decreases requirements for allogeneic blood transfusion and chest reexploration in patients undergoing cardiac surgery. Whether rFVIIa increases the risk of postoperative adverse events is unclear. We tested whether rFVIIa administration was associated with increased mortality and neurologic and renal morbidity in patients undergoing cardiac surgery. Risk of thromboembolic complications and the dose-response of rFVIIa on mortality and morbidity were also evaluated. Methods Of 27,977 patients who had complex cardiac surgery, 164 patients (0.59%) received rFVIIa perioperatively. Using propensity-matching techniques, patients were matched to a maximum of 3 control patients. Patients who received rFVIIa were compared with control patients on risk of mortality, neurologic and renal morbidity, and thromboembolic complications, including a composite of myocardial infarction, pulmonary embolism, and deep venous thrombosis. A corresponding dose-response analysis using multivariable logistic regression was also performed. Results Propensity techniques successfully matched 144 patients (88%) with 359 control patients. Of patients who received rFVIIa, 40% experienced in-hospital mortality compared with 18% of control patients (odds ratio, 2.82; 98.3% confidence interval, 1.64 to 4.87; p p = 0.002); however, neurologic morbidity and thromboembolic complications were not different among groups. High-dose rFVIIa (>60 μg/kg) did not increase the risk for mortality compared with treatment with low-dose rFVIIa ( Conclusions Administration of rFVIIa is associated with increased mortality and renal morbidity in patients undergoing cardiac surgery.
Prenatal development of excitability in cat retinal ganglion cells: action potentials and sodium currents

The development of precise retinofugal projections is dependent on activity-mediated events, but as yet nothing is known about the ontogeny of excitable membrane properties in retinal ganglion cells (RGCs). In order to begin to understand how functional maturity is attained in these neurons, whole-cell patch-clamp recordings were obtained from acutely dissociated RGCs of fetal and postnatal timed- pregnant cats. Current-clamp recordings revealed a pronounced developmental increase in the proportion of RGCs capable of generating action potentials. At embryonic day 30 (E30), 5 weeks before birth and during a time when RGCs are still being generated, electrical stimulation elicited spikes in only a third of the cells. None of these neurons were capable of multiple discharges in response to maintained depolarization. The proportion of spiking neurons increased during ontogeny, such that by E55 all RGCs could be induced to generate action potentials, with the majority manifesting repetitive spiking patterns. Application of tetrodotoxin abolished spike activity of all fetal RGCs, indicating that sodium-mediated action potentials are present very early in development. At the same time, voltage-clamp recordings revealed significant ontogenetic modifications in several key properties of the sodium currents (INa). These were (1) a twofold increase in Na current densities; (2) a shift in the voltage dependence of both activation and steady state inactivation: with maturity, sodium currents activate at more negative potentials, while steady state inactivation of INa occurs at less negative potentials; and (3) a decrease in decay time constants of the Na current, at membrane potentials negative to -15 mV. These developmental changes were largely restricted to the period of axon ingrowth (E30-E38), suggesting that maturation of INa is not the limiting factor for the onset of activity- dependent restructuring of retinofugal projections.
The Best Shape for a Crossdock

Within both retail distribution and less-than-truckload transportation networks crossdocks vary greatly in shape. Docks in the shape of an I, L, or T are most common, but unusual ones may be found, including those in the shape of a U, H, or E. Is there a best shape? We show that the answer depends on the size of the facility and on the pattern of freight flows inside. Our results suggest that many large crossdocks in practice suffer from poor design that increases labor costs on the dock.
Counting problems in Apollonian packings

An Apollonian circle packing is a classical construction which is made by repeatedly inscribing circles into the triangular interstices in a Descartes configuration of four mutually tangent circles. Remarkably, if the original four circles have integer curvature, all of the circles in the packing will have integer curvature, making the packings of interest from a number theoretic point of view. Many of the natural arithmetic problems have required new and sophisticated tools to solve them. The reason for this difficulty is that the study of Apollonian packings reduces to the study of a subgroup of GL4(Z) which is thin in a sense that we describe in this article, and arithmetic problems involving thin groups have only recently become approachable in broad generality. In this article, we report on what is currently known about Apollonian packings in which all circles have integer curvature and how these results are obtained. This survey is also meant to illustrate how to treat arithmetic problems related to other thin groups.
Versatile 3-channel high-voltage power supply for microchip capillary electrophoresis

The fabrication of a battery operated 3-channel high voltage power supply for microchip capillary electrophoresis is described. The power supply consists of two positive and one negative DC–DC converters, a microprocessor controlled timer, a battery and a transformer to recharge the battery and feed the high voltage relays. This arrangement allows the possibility to control the potentials applied in the 0 to ±4000 V range to a variety of microchip setups. It can also be easily adapted to perform either gated or pinched injection. The inclusion of a rechargeable battery was adopted to feed the DC–DC converters to reduce noise levels and achieve portability.
ON STABILIZERS OF SOME TEICHMÜLLER DISKS IN POINTED MAPPING CLASS GROUPS

We prove that for each Riemann surface of finite analytic type (p, n) with p ≥ 2, there exist uncountably many Teichmuller disks Δ in the Teichmuller space T(S), where S = - {a point a}, with these properties: (1) the natural projection j: T(S) → T() defined by forgetting a induces an isometric embedding of each Δ into T(); and (2) the stabilizer of each Teichmuller disk Δ in the a-pointed mapping class group of S is trivial.
Pharmacogenetic considerations in the treatment of psychiatric disorders.

Importance of the field: Despite continued efforts to optimize pharmacological treatment for individuals with psychiatric disorders, efficacy and tolerability of medication remains highly variable. In addition to clinical heterogeneity, diagnostic uncertainty, environmental, social factors, and genetic factors have been identified as playing an important role in the interindividual differences in therapeutic and toxic drug effects.Areas covered in this review: This article describes recent developments in the field of psychiatric pharmacogenetics and focuses on antidepressant, antipsychotic, anticonvulsant, and mood-stabilizing drugs.What the reader will gain: Recent findings from pharmacogenetic clinical trials are reviewed and clinical implications are discussed.Take home message: Although current data are too sparse to allow the development of guidelines for using pharmacogenetic testing in routine clinical practice, the field of psychiatric pharmacogenetics is rapidly developing and identification of ...
Human-centered socially assistive robotics for rehabilitation: Is it time for a robot coach?

Human-robot interaction (HRI) for socially assistive applications is a growing research area at the intersection of robotics, health science, psychology, social and cognitive science. Assistive robotics has the potential to enhance quality of life for large user populations. Individuals in rehabilitation therapy are potential beneficiaries of socially assistive technology, both for improved mobility and for improved outcomes in recovery. Socially assistive robotics (SAR) focuses on assisting through social, not physical, interaction (D. Feil-Seifer and M.J. Mataric, 2005). SAR can offer cost-effective methods for aiding recovery by maximizing the patient motivation both during and after structured rehabilitation. We are developing a general and affordable technology that can provide supplemental therapy, supervision, and encouragement of functional practice for individuals with impaired movement capability in an effort to significantly augment in- and out-of clinic care. This creates a critical niche for SAR, wherein human-robot interaction can be used not to replace physical or occupational therapists, but to augment human care as a readily available individualized rehabilitation aid.
A digital micro-mirror device-based system for the fabrication of microfluidic tissue array

Micro-Electro-Mechanical Systems (MEMS) technologies demonstrate the potential for applications in the field of tissue engineering, regenerative medicine, and life sciences. The development of a successful model would require investigations of the targeted organ. Computer tomography (CT) and magnetic resonance imaging (MRI) allow for biomodeling of the targeted organ. The Digital Micro-mirroring Microfabrication system (DMM) would utilize its dynamic micro mirrors to fabricate the developed tissue construct according to its desire design and characteristics. The DMM has the capabilities to fabricate many advantageous devices, amongst them; microfluidics systems have the most tissue engineering, regenerative medicine, and life sciences applications to develop in vitro tissue models. Unlike many microfabrication techniques and or devices available to fabricate tissue model, this system eliminates the need for mask by incorporating a dynamic maskless fabrication technique. Since the system can develop models on a micro-scale level, this would make many investigation more economic; requiring less reagents, cells, and above all; it will allow for consistency in experimental analysis to due limited interactions with the end user.
Hugoniot equation of state of anorthite glass and lunar anorthosite

Twenty-one Hugoniot experiments were conducted on an amorphous material of anorthite composition, in the pressure range 8–120 GPa, using both routine and new methods. Two Hugoniot measurements at about 120 GPa were made on lunar gabbroic anorthosite (Apollo 15, 418). Theoretical Hugoniots are constructed for both materials assuming they are disproportionate to their component oxides. These accurately predict the P-ρ behaviour of the lunar anorthosite Hugoniot at 120 GPa and the anorthite glass Hugoniot above 50 GPa, but overestimate the shock temperatures of anorthite glass. The mixed oxide model fails to predict the release paths of either material. We conclude that the mixed oxide model is a good description of the bulk properties of the high-pressure phases of anorthite, but does not represent the actual phases. A significant enrichment of calcic refractory material in the Earth's lower mantle is not precluded by the bulk properties of the anorthite high-pressure phases.
Considerations related to the effusional separation of equilibrium components of high temperature water—the separation of helium-argon mixtures

Abstract Stage separation efficiencies and gains achieved by the effusional separation of helium-argon mixtures by thin filters having pores which go straight through the filters have been measured at Knudsen numbers of 25, 10, and 5. The experimental results are compared with the analytical treatment of Present and de Bethune for the purpose of providing information which will be useful in predicting constraints which are likely to be encountered in the high temperature effusional separation of the equilibrium components of water.
Cut Resistance of High-strength Yarns

The cut resistance of three high-strength yarns under tension-shear loading conditions was measured by pressing a knife blade transversely at a constant rate against a yarn gripped at its ends. The load-deflection relation and the energy required to cut through the yarn were determined for Kevlar (aramid), Spectra (polyethylene), and Zylon (polybenzobisoxazole, or PBO). The cut energy and strain to initiate cutting were highest for Zylon, least for Kevlar, and depended on the slicing angle, the sharpness of the blade, and the pre-tension in the yarn. The dependencies are explained by changes in failure mode of the fibers within the yarn. The test provides input needed for computational simulations of ballistic response of fabrics to sharp fragments and should be useful in designing slash-resistant gloves and clothing.
A 24GHz, +14.5dBm fully-integrated power amplifier in 0.18 /spl mu/m CMOS

A 24 GHz, +14.5 dBm fully-integrated power amplifier with 50 /spl Omega/ input and output matching is fabricated using 0.18 /spl mu/m CMOS transistors. To enable this, a shielded-substrate coplanar waveguide transmission line structure is used to achieve low loss and small area. The power amplifier achieves a power gain of 7 dB and a maximum single-ended output power of +14.5 dBm with a 3 dB bandwidth of 3.1 GHz, while drawing 100 mA from a 2.8 V supply. The chip area is 1.26 mm/sup 2/.
Hyperparathyroidism after radioactive iodine therapy.

Abstract Background Radioactive iodine (RAI) treatment has been suggested to cause primary hyperparathyroidism (HPT). We describe a series of patients with HPT and a history of RAI exposure. Methods Patient demographic and clinical information was evaluated, including the latency time to the development of HPT after RAI exposure. Results We treated 11 patients with HPT and a history of RAI exposure. RAI treatment was administered for benign thyroid disease in 9 (82%) cases. Thirty-six cases of HPT after RAI exposure in the English literature were compiled for further analysis. In this collective experience, the average latency time to the development of HPT after RAI treatment was 13.5 ± 9.1 years and was found to be inversely correlated with age at RAI exposure. Conclusions Patients who undergo RAI treatment are at risk of developing HPT, and this risk appears to increase in elderly patients. Serum calcium surveillance is recommended for patients who have undergone RAI treatment.
Anatomy of a Real-Time Intrusion Prevention System

Host intrusion prevention systems for both servers and end-hosts must address the dual challenges of accuracy and performance. Researchers have mostly focused on addressing the former challenge, suggesting solutions based either on exploit- based penetration detection or anomaly-based misbehavior detection, but yet stopping short of comprehensive solutions that leverage merits of both approaches. The second challenge, however, is rarely addressed; doing so comprehensively is important since these systems can introduce substantial overhead and cause system slowdown, more so when the system load is high. We present Rootsense, a holistic and real-time intrusion prevention system that combines the merits of misbehavior- based and anomaly-based detection. Four principles govern the design and implementation of Rootsense. First, Rootsense audits events within different subsystems of the host operating system and correlates them to comprehensively capture the global system state. Second, Rootsense restricts the detection domain to root compromises only; doing so reduces run-time overhead and increases detection accuracy (root behavior is more easily modeled than user behavior). Third, Rootsense adopts a dual approach to intrusion detection - a root penetration detector detects activities that exploit system vulnerabilities to penetrate the security perimeter, and a root misbehavior detector tracks misbehavior by root processes. Fourth, Rootsense is designed to be configurable for overhead management allowing the system administrator to tune the overhead characteristics of the intrusion prevention system that affect foreground task performance. A Linux implementation of Rootsense is analyzed for both accuracy and performance, using several real-world exploits and a range of end-host and server benchmarks.
ZigBee-based Wireless Intra-oral Control System for Quadriplegic Patients

A human-to-computer system that includes a wireless intra-oral module, a wireless coordinator and distributed wireless controllers, is presented. The state-of-the-art ZigBee protocol is employed to achieve reliable, low- power and cost-efficient wireless communication between the tongue, computer and controllers. By manipulating five buttons on the wireless intra-oral module using the tongue, the subject can control cursors, computer menus, wheelchair, lights, TV, phone and robotic devices. The system is designed to improve the life quality of patients with stroke and patients with spinal cord injury.
Modeling Input Motion Boundary Conditions for Simulations of Geotechnical Shaking Table Tests

This paper discusses the effects of using different input-motion-boundaryconditions on the sensitivity of numerical simulations results to errors in material properties of a specimen tested on a shaking table. In the flexibleactuator-prescribed-force-boundary-condition, input is specified by a force across an actuator element that connects the shaking table to a reaction mass. In the prescribed-displacement-boundary-condition, the measured shaking table motion in the experiment is prescribed in the simulation. The flexibleactuator-prescribed-force approach yielded smaller, almost constant sensitivity of simulation results to input properties. The prescribeddisplacement approach yielded larger and more variable sensitivities. The sensitivity of results depends on the how the boundary conditions are handled has further implications: the assessment of a comparison between a simulation and an experimental result should be performed with due consideration to the effect of the boundary conditions on the comparison, and numerically determined sensitivities may not be physically meaningful if the boundary condition is not accurately modeled. DOI: 10.1193/1.3383214
MOLECULAR AND GENETIC INSIGHTS INTO T CELL ANTIGEN RECEPTOR SIGNAL TRANSDUCTION

T lymphocytes are relatively quiescent cells, poised in the G0 stage of the cell cycle, until they encounter antigen. The initiation of an immune response by T cells requires the recognition of antigen by the T cell antigen receptor (TCR) and the conversion of this recognition event into biochemical signals that can induce a cellular response. This cellular response leads to the clonal expansion of antigen-specific differentiated effector T cells.
Security Breaches, Privacy Intrusions, and Reporting of Computer Crimes

AbstractComputer crimes, in their true sense, typically involve unauthorized access, sabotage, theft of data, or theft of services. The occurrence of such crimes and other information security breaches continue at a fast pace, but there is much more criminal activity occurring in cyberspace than organizations are willing to report. The purpose of this paper is to identify current trends in computer security intrusions, to determine why they are not being fully reported, and to discuss one of the primary sources of United States criminal law that is available to law enforcement authorities for the punishment of computer crimes.
Editorial Note: From the Neocolonial ‘Transitional’ to Indigenous Formations of Justice

It may seem odd that I am responding to the honor of the editors’ invitation to write this editorial note by questioning the premise of the current conception of the field of ‘transitional justice’ itself. The implied assumption of this field, it seems to me, is that the ‘developing’ society under examination is in transition from the state of being A, which we know, to becoming B, which we can predict. The precise question or theme of the study may vary, but the underlying inquiry seems to be whether that society can still maintain an acceptable level of what we, the ‘international community,’ recognize as justice during transition. I am not saying that this is true of every scholar or social actor in the field, but the explicit or implicit purpose of those whose work is informed by this conception of transitional justice seems to be as follows: Let us promote an intermediate level or degree of ‘justice,’ as we know or accept it to be, until the situation is ready for the next phase toward the ultimate goal of fulfillment of our vision of justice as it should be practiced everywhere in the world. Another possible purpose of scholars or social actors is to promote an ‘appropriate’ conception of justice for issues that are particular to ‘transition,’ such as finding an acceptable compromise on accountability for atrocities committed during a conflict in order to facilitate the process of ‘peacebuilding.’ In these or other similar scenarios, preference is given to a standard of justice that is mandated by the international community over indigenous or ‘traditional’ practices that are unacceptable because they are inconsistent with ‘universal’ human rights norms, as proclaimed by the international community. It seems to me that this external mandate is so much the presumed standard that even the possibility of an indigenous alternative conception of justice is not taken seriously at a theoretical or empirical level. If or to the extent that what I am saying is true, transitional justice scholarship and strategies are neocolonial because they view indigenous conceptions of justice as a distraction from the grand ‘modernizing’ mission of North Atlantic societies, 1 in the guise of the so-called ‘international community’ this time. I am using
Nonlinear elastic response of strong solids: First-principles calculations of the third-order elastic constants of diamond

Accurate theoretical calculations of the nonlinear elastic response of strong solids (e.g., diamond) constitute a fundamental and important scientific need for understanding the response of such materials and for exploring the potential synthesis and design of novel solids. However, without corresponding experimental data, it is difficult to select between predictions from different theoretical methods. Recently the complete set of third-order elastic constants (TOECs) for diamond was determined experimentally, and the validity of various theoretical approaches to calculate the same may now be assessed. We report on the use of density functional theory (DFT) methods to calculate the six third-order elastic constants of diamond. Two different approaches based on homogeneous deformations were used: (1) an energy-strain fitting approach using a prescribed set of deformations, and (2) a longitudinal stress-strain fitting approach using uniaxial compressive strains along the [100], [110], and [111] directions, together with calculated pressure derivatives of the second-order elastic constants. The latter approach provides a direct comparison to the experimental results. The TOECs calculated using the energy-strain approach differ significantly from the measured TOECs. In contrast, calculations using the longitudinal stress-uniaxial strain approach show good agreement with the measured TOECs and match the experimental values significantly better than themore » TOECs reported in previous theoretical studies. Lastly, our results on diamond have demonstrated that, with proper analysis procedures, first-principles calculations can indeed be used to accurately calculate the TOECs of strong solids.« less
Phorbol ester-induced augmentation and inhibition of epinephrine-stimulated adenylate cyclase in S49 lymphoma cells

The effects of 4-beta phorbol 12-myristate 13-acetate (PMA) on hormone and forskolin-stimulated adenylate cyclase were evaluated in S49 lymphoma cells. Treatment of wild type (WT) S49 cells with PMA caused stimulation, inhibition or had no effect on epinephrine stimulation of cAMP accumulation. The effect observed was dependent on the length of PMA treatment, the concentration of PMA and the concentration of hormone (or forskolin) used to stimulate cAMP accumulation. Longer treatment times with PMA and higher PMA concentrations favored the inhibitory effects. Pretreating WT with 0.5 microM PMA for 18 min caused an increase in the EC50 and maximal levels for epinephrine stimulation of cAMP accumulation. Thus inhibition was seen at relatively low epinephrine concentrations and augmentation with high concentrations. The inhibitory effects of PMA on epinephrine-stimulated adenylate cyclase activity were observed only at low free Mg++ concentrations (0.75 mM). The effects of PMA on PGE1-stimulated cAMP accumulation were similar to those observed for epinephrine. In S49 WT cells 100 nM PMA augmented 5 microM forskolin-stimulated cAMP accumulation; however with 100 microM forskolin, PMA effects were minimal. PMA also attenuated Gi-mediated Gpp(NH)p inhibition of forskolin-stimulated adenylate cyclase in both WT and cyc- membranes, resembling the effects of pertussis toxin. The effects of various phorbol analogues on epinephrine-stimulated cAMP accumulation were as follows: 4 beta-phorbol 12,13-didecanoate had similar effects to PMA, 4 alpha-phorbol 12,13-didecanoate had no effects and 1-oleoyl, 2-acetylglycerol augmented epinephrine-stimulated cAMP accumulation at concentrations greater than or equal to 5 microM. Our results are consistent with a dual mechanism of PMA action on adenylate cyclase involving protein kinase C-mediated phosphorylation of Gi and of the beta-adrenergic receptor, the former leading to augmentation and the latter to inhibition of hormone-stimulated adenylate cyclase.
Reactive removal of 2-chloroethyl ethyl sulfide vapors under visible light irradiation by cerium oxide modified highly porous zirconium (hydr) oxide

Abstract Highly porous cerium oxide modified Zr(OH) 4 samples were synthesized using a simple one stage urea precipitation method. The amorphicity level of zirconium hydroxide did not change upon addition of cerium oxide particles. A unique aspect of the cerium oxide-modified materials is the presence of both the oxide (CeO 2 ) and hydroxide (Zr(OH) 4 ) phases resulting in a unique microporous structure of the final material. Extensive characterization using various chemical and physical methods revealed significant differences in the surface features. All synthesized materials were microporous and small additions of cerium oxide affected the surface chemistry. These samples were found as effective catalysts for a decontamination of mustard gas surrogate, 2-chloroethyl ethyl sulfide (CEES). Cerium oxide addition significantly decreased the band gap of zirconium hydroxide. Ethyl vinyl sulfide and 1,2-bis (Ethyl thio) ethane were identified as surface reaction products.