cssi/SciSciGPT-SciSciNet huggingface dataset:
Properties of poly(ethylene terephthalate) prepared by high-pressure extrusion in a capillary die

The procedure of Southern and Porter has been used to prepare poly(ethylene terephthalate) segments by high-pressure extrusion in an Instron capillary rheometer at temperatures from 245° to 265°C. X-Ray measurements of crystalline orientation along the axis of long-growth segments showed that segment properties were controlled by the time-dependent crystallization of polymer melt in the rheometer reservoir. During the initial stage of extrusion, a highly oriented, translucent segment was generated by flow-induced crystallization. However, formation of the translucent morphology eventually stopped, and thereafter a poorly oriented, opaque segment was generated by solid-state extrusion. From wide- and small-angle x-ray scattering, differential scanning calorimetry, and density measurements, it was determined that the most perfect morphologies were prepared at an extrusion temperature of 265°C. In addition to having the highest degree of crystalline orientation, translucent segments extruded at 265°C have a peak melting point of 267°C and a crystallinity value of 62%. Hot-stage optical microscopy showed that the translucent segments contained axially aligned fibrous crystals whose birefringence persisted to 290°C. The exceptional thermal stability of the segments was corroborated by the results of shrinkage tests at temperatures near the melting point; even after 1 hr at 260°C, the shrinkage did not exceed 7%. The accumulated evidence suggests that the translucent segments contain an extended-chain component.
Multiple Contexts, Multiple Methods: A Study of Academic and Cultural Identity among Children of Immigrant Parents.

Multiple methods were used to examine the academic motivation and cultural identity of a sample of college undergraduates. The children of immigrant parents (CIPs, n = 52) and the children of non-immigrant parents (non-CIPs, n = 42) completed surveys assessing core cultural identity, valuing of cultural accomplishments, academic self-concept, valuing of academics, and feelings of belonging at the university. Survey results revealed that CIP's placed a greater emphasis on their cultural identity than non-CIPs. In addition, core cultural identity was associated with all three of the motivation scales for CIPs, but only with valuing of academics for the non-CIPs. Implicit association tests revealed that CIPs and non-CIPs both associated success with Caucasians more strongly than with Hispanics, a result that was true even for the Hispanic participants in the study. Finally, a sub-group of 11 CIPs were interviewed to gain additional insights regarding the association between cultural identity and academic motivation. The influence of the multiple contexts in which CIPs operate is used to interpret these results.
On the difference between quantum beats in impulsive stimulated raman scattering and resonance Raman scattering

Abstract Recent femtosecond transient absorption measurements in triphenylmethane dyes have shown quantum beats in the absorption recovery. A measurement of the phase of the quantum beats as a function of the probe wavelength indicates that the beats have significantly different character than those seen in impulsive stimulated Raman scattering. A possible explanation for the variation of the phase with wavelength is presented.
Phantom study for volume-of-interest breast imaging using differential phase contrast cone beam CT (DPC-CBCT)

Differential phase contrast (DPC) imaging is reported to be able to deliver higher contrast-to-noise ratio (CNR) compared to attenuation-based x-ray imaging technologies. Due to the nature of attenuation contrast, the conventional cone beam CT (CBCT) technology has limitations in characterizing breast lesions with sufficiently high contrast and spatial resolution. As an alternative, the grating-based DPC-CBCT technology is potentially a powerful tool for breast imaging. However, limited by current grating fabrication techniques, a full field-of-view (FOV) that covers the whole breast is not practical at present. Previously by our group, a volume-of-interest (VOI) imaging method, which incorporates DPC-CBCT into a dedicated attenuation-based CBCT imaging system, was presented. In the method, the CBCT scan was performed to localize the suspicious volume and then a VOI scan by DPC-CBCT characterized the suspicious volume with higher contrast and resolution. In this work, we investigated the performance of DPC-CBCT VOI imaging by performing a phantom study using our bench-top DPC-CBCT system with a hospital-grade X-ray tube. A cylinder water phantom with a size of over twice of the FOV of our DPC-CBCT system was designed. The phantom contains four different materials and it was scanned at four different dose levels. In thick object scanning, phase wrapping errors cause artifacts for DPC-CBCT VOI imaging. A low-pass filter was designed to reduce the artifacts. In order to compare the DPC-CBCT VOI with attenuation-based CBCT, the scanning data were used to reconstruct both phase coefficient image and attenuation coefficient image. The reconstructed images will be quantitatively and visually evaluated with regards to contrast, noise level and artifacts.
Reactivity of the molybdenacarbaborane anion [2,2,2,2-(CO)4-closo-2,1-MoCB10H11]−: metal oxidation versus cage substitution

In CH2Cl2 solutions, the MoII salt [N(PPh3)2][2,2,2,2-(CO)4-closo-2,1-MoCB10H11] 1 is oxidized by iodine (1 equiv.) in the presence of CNBut (4 equiv.) affording the MoIV complex [2,2,2,2-(CNBut)4-2-I-closo-2,1-MoCB10H11], the structure of which was established by X-ray diffraction. In contrast, under similar conditions the corresponding tungsten salt yields a mixture of [2,2,2-(CNBut)3-2-CO-2-I-closo-2,1-WCB10H11] and [2,2-(CNBut)2-2,2-(CO)2-2-I-closo-2,1-WCB10H11]. Treatment of 1 with iodine in tetrahydrofuran yields the MoII species [N(PPh3)2][2,2,2-(CO)3-2-I-7-{O(CH2)4}-closo-2,1-MoCB10H10], the structure of which was also confirmed by X-ray diffraction. The latter with iodine and S(CH2)4 gives [2,2,2-(CO)3-2-I-3-{S(CH2)4}-11-{O(CH2)4}-closo-2,1-MoCB10H9]. Using CH2Cl2 as solvent, 1 reacts with thioethers L [L = S(CH2)4, cyclo-1,4-S2(CH2)4, cyclo-1,4,7-S3(CH2)6, cyclo-1,4,7,10-S4(CH2)8] and iodine to form [2,2,2-(CO)3-2,3-μ-I-n-L-closo-2,1-MoCB10H9] (isomers, n = 7 and 11) and [2,2,2-(CO)3-2-I-3,11-L2-closo-2,1-MoCB10H9] [except L = cyclo-1,4,7,10-S4(CH2)8]. The molecular structures of [2,2,2-(CO)3-2,3-μ-I-7-{cyclo-1,4,7-S3(CH2)6}-closo-2,1-MoCB10H9] and [2,2,2-(CO)3-2-I-3,11-{cyclo-1,4-S2(CH2)4}2-closo-2,1-MoCB10H9] were determined by X-ray diffraction, confirming both to have doubly B-substituted cages and the former to contain a novel iodide bridge between molybdenum and a cage-boron atom.
All-atom Models For RNA And Proteins: Simulating Folding And Function

The energy landscapes of RNA and protein folding are inextricably linked to biological function. Using All-atom structure-based models, we seek to determine the physical properties that govern folding and function of biopolymers. With these models we have studied folding, conformational rearrangements and ligand binding for a variety of protein and RNA systems. In one application of the model, we have characterized the complete folding/unfolding landscape of the SAM-1 riboswitch. Riboswitches are structured RNA fragments that alter their conformation in response to elevated concentrations of specific metabolites. To better understand the role and mechanism of ligand binding, we simulated the RNA in a bath of ligands. Key findings include the identification of the rate limiting step in SAM-1 folding and that ligand binding specifically targets this step. These results illustrate the close link between folding and function in this riboswitch. For protein function, results from Adenylate Kinase will be presented. Adenylate Kinase is an enzyme that undergoes large scale conformational rearrangements during catalysis. Using our All-atom models we have been able to quantify the free energy barriers associated with these rearrangements and identify key structural components that regulate these motions.
Understanding the cross section for isolated prompt photon production

Abstract We describe the proper evaluation in perturbation theory of the cross section for prompt photon production with an isolation cut. It is convenient to separate the cross section into two components: a purely perturbative piece and a nonperturbative piece. If the opening angle (δ) of the photon isolation cone is not too small, the isolation cut on the nonperturbative fragmentation functions can be handled by proper choice of the fragmentation scale. For the pertutbative component, we show that as long as the energy resolution parameter (ϵ) is a finite number, the isolated cross section is infrared finite. From an explicit next-to-leading order calculation, we find that the leading soft gluon correction for the isolated cross section is proportional to sin 2 ( 1 2 δ)( α s π ) ln ( 1 ϵ ) times the leading order contribution. If ϵ is too small, the anomalous soft gluon contributio can be resummed.
Electrostatic control of the tryptophan radical in cytochrome c peroxidase.

Previously a K+-binding site, analogous to that found in ascorbate peroxidase (APX), was engineered into cytochrome c peroxidase (CcP) to test the hypothesis that the bound K+ influences the stability of the Trp191 cation radical formed during the CcP catalytic cycle (Bonagura et al., (1996) Biochemistry 35, 6107 and Bonagura et al., (1999) Biochemistry 38, 5528). Characterization of this mutant, designated CcPK2, showed that the stability of the Trp191 cation radical is dependent on the occupancy of the engineered K+ site and that the Trp191 radical was much less stable in this mutant than in wild-type CcP. The mutations Met230Leu, Met231Gln, and Met172Ser have now been constructed on the CcPK2 mutant template to test if the Met residues also contribute to the stabilization of the Trp191 cation radical. Crystal structures show that the mutations affect only the local structure near the sites of mutation. Removal of these electronegative residues located less than 8 A from the Trp radical results in a fur...
Facilitation of learning performance by posttrial etherization

House mice of inbread strains C57BL/6J and DBA/2J were given brief posttrial exposures to vapor of liquid diethyl ether at an average room temperature of 24°C. Mean duration of exposure was 9 see. The procedure did not produce loss of the righting response. The behavioral effect was to enhance foot-shock escape learning performance of DBA/2J mice, but not of C57BL/6J mice. These results continue to confirm a difference between these strains in the behavioral consequences of posttrial etherization and are consistent with the notion that low posttrial doses of ether produce facilitation or no effect upon learning performance.
Nurse competence in aging overview

This article provides an overview of the Nurse Competence in Aging (NCA) project. Specifically, it reviews demographics, articulates the need to increase the gerontology presence within specialty nursing, and analyzes the way in which NCA is addressing that need in partnership with specialty associations.
Structure of the iso form of colchicine. Demethylisothiocolchicine.

Abstract Demethylisothiocolchicine forms monoclinic crystals, space group P2 1 , a = 11.906, b = 8.713, c = 10.004 A; β = 89.44°; Z = 2. The crystal and molecular structure was determined from 1911 independent x-ray reflections and refined to R = 0.04. The molecule has the same overall shape as active colchicine derivatives but one methoxy group has a different conformation from that found in other compounds.
Design of ultrathin nanostructured polyelectrolyte-based membranes with high perchlorate rejection and high permeability

Abstract The presence of perchlorate in drinking water sources is an issue of overwhelming concern in United States. Commercial reverse osmosis (RO) membranes show high rejection of perchlorate ions but with very low water permeability. We propose the modification of commercial nanofiltration (NF) membranes by layer-by-layer (LbL) assembly in order to enhance the ion rejection of these membranes to the same level as commercial RO membranes, but with much higher permeability. Poly allylamine hydrochloride (PAH) and poly acrylic acid (PAA) were the two polyelectrolytes used for surface modification. We found that, when both these polyelectrolytes were deposited on a NF 90 membrane at a pH of 6.5 and crosslinked with glutaraldehyde, we were able to achieve around 93% perchlorate rejection at a pressure of 5 bar with 10 ppm feed concentration. This was almost equal to the rejection offered by SW 30 membrane and higher than a BW 30 membrane under the same conditions of pressure and feed concentration. Most importantly, the modified membranes had 1.5 times the permeability of BW 30 membrane and 6 times that of SW 30. These membranes, therefore, had much superior permselectivity than the commercial membranes. In fact, this was one of the highest values of permselectivity reported so far for a PEM-based RO membrane targeting monovalent ion removal. Only 3 bilayers, with an overall thickness of just 20 A, were sufficient to achieve such a high rejection. The mechanism of ion rejection by these modified membranes was based on size-based exclusion rather than charge-based separation.
Non-protein amino acid-insect interactions—I. Growth effects and symptomology of l-canavanine consumption by tobacco hornworm, Manduca sexta (L.)

Abstract 1. 1. Incorporation of l -canavanine, a naturally occurring structural analogue of arginine, into the artificial diet of the tobacco hornworm larvae, Manduca sexta (L.), produced severely toxic effects. 2. 2. The toxic effects included enhanced larval mortality, decreased larval growth rates and malformed pupae and adults. 3. 3. Larval response to canavanine was concentration dependent at least over a range of 3–45 mM. 4. 4. Diets supplemented with arginine, ornithine, glycine and lysine were not toxic to fifth instar hornworms.
Prevalence of arrhythmias during exercise stress testing in patients with congenital heart disease and severe right ventricular conduit dysfunction.

The utility of cardiopulmonary exercise testing (CPET) to define the risks of arrhythmia and sudden death in postoperative patients with congenital heart disease (CHD) remains uncertain. As part of the US Melody valve trial, prospective standardized CPET, along with echocardiography, cardiac magnetic resonance imaging, and cardiac catheterization, were performed in 170 CHD patients with right ventricular outflow tract conduit dysfunction before Melody valve implantation. Ventricular premature complexes (VPC) occurred in 75 patients (44%) and were common during all phases of CPET (13% baseline, 24% exercise, and 23% recovery). Although no subjects had sustained arrhythmias, 2 had nonsustained ventricular tachycardia and 3 had nonsustained supraventricular tachycardia during recovery. There were no statistically significant differences between patients with or without VPCs in echocardiographic, cardiac magnetic resonance imaging, or catheterization measures of cardiac function. However, clinical parameters of age, New York Heart Association functional class ≥II, and ≥3 cardiac surgical procedures were correlated with VPCs. Persistent ventricular ectopy during all exercise stages was present in 11 patients (6.5%), including 3 of the 4 patients who died during follow-up. In conclusion, VPCs were common during CPET, although they were not correlated with various measures of hemodynamic impairment; conversely, increased age, functional class, and number of surgeries were correlated with an increased prevalence of VPCs. CPET appears to be of minimal risk for sustained arrhythmia provocation in CHD patients with right ventricular outflow tract conduits and various degrees of advanced subpulmonary ventricular dysfunction.
A high-level programming environment for packet trace anonymization and transformation

Packet traces of operational Internet traffic are invaluable to network research, but public sharing of such traces is severely limited by the need to first remove all sensitive information. Current trace anonymization technology leaves only the packet headers intact, completely stripping the contents; to our knowledge, there are no publicly available traces of any significant size that contain packet payloads. We describe a new approach to transform and anonymize packet traces. Our tool provides high-level language support for packet transformation, allowing the user to write short policy scripts to express sophisticated trace transformations. The resulting scripts can anonymize both packet headers and payloads, and can perform application-level transformations such as editing HTTP or SMTP headers, replacing the content of Web items with MD5 hashes, or altering filenames or reply codes that match given patterns. We discuss the critical issue of verifying that anonymizations are both correctly applied and correctly specified, and experiences with anonymizing FTP traces from the Lawrence Berkeley National Laboratory for public release.
Techniques for Metric Photography

Three techniques for metric photography are described. In the first, missile position-time data are obtained from measurement of photographs of the virtual image produced in a precision-ground sphere by a timed stroboscopic point-source lamp. In the second, a rotating circular film disc is covered with sector-shaped exposures using a timed stroboscopic lamp. In the third, the previously described techniques are combined to obtain data simultaneously.
MANAGEMENT OF TREATMENT-RESISTANT UNIPOLAR AND CHRONICALLY DEPRESSED PATIENTS

Although "treatment-resistant depression" is a widely used and empirically useful concept, varying interpretations of its operational definition in the literature and an absence of well-designed placebo-controlled trials have resulted in a confusing landscape in which the direction to be taken in an individual case is likely to be influenced as much by anecdote or theoretic speculation as by published data. Treatment resistance is most simply defined as the persistence of clinically meaningful depressive symptoms after 6 weeks of antidepressant treatment, given at therapeutic dosages and taken by the patient as prescribed. More stringent definitions require a similar lack of response to one or more subsequent structurally different antidepressants, and some investigators have suggested that no patient should be considered resistant until a course of electroconvulsive therapy (ECT) has been administered. 2,6,9,22,34 The definition of outcome, like that of an adequate pharmacologic trial, has varied. In some studies, it is dependent on a percentage change from baseline in objective behavioral ratings of mood, whereas in others, it is linked to global assessments of overall functional ability and complete remission. 37,43,85,86 Most early attempts at definition of treatment resistance presumed a homogenous population; more recently, investigators such as Nierenberg and others 76,77 have suggested that treatment resistance might best be defined in the context of a continuum in which the degree of treatment resistance is ascertained by taking into account such things as the total number of antidepressant trials and their quality, the number of failed treatments, and the degree of lack of response.
The Dual Effect of Rac2 on Phospholipase D2 Regulation That Explains both the Onset and Termination of Chemotaxis

We document a biphasic effect of Rac2 on the activation and inhibition of PLD2. Cells overexpressing Rac2 and PLD2 simultaneously show a robust initial ( 30 min) greatly diminished over PLD2-only controls. The first phase is due to the presence of a Rac2-PLD2 positive-feedback loop. To explain the mechanism for the Rac2-led PLD2 inhibition (the second phase), we used leukocytes from wild-type (WT) and Rac2 / knockout mice. Rac2 / cells displayed an enhanced PLD2 (but not PLD1) enzymatic activity, confirming the inhibitory role of Rac2. Late inhibitory responses on PLD2 due to Rac2 were reversed in the presence of phosphatidylinositol 4,5-bisphosphate (PIP 2) both in vitro (purified GST-PH-PLD2, where GST is glutathione S-transferase and PH is pleckstrin homology) and in vivo. Coimmunoprecipitation and immunofluorescence microscopy indicated that PLD2 and Rac2 remain together. The presence of an “arc” of Rac2 at the leading edge of leukocyte pseudopodia and PLD2 physically posterior to this wave of Rac2 was observed in late chemotaxis. We propose Rac-led inhibition of PLD2 function is due to sterical interference of Rac with PLD2’s PH binding site to the membrane and deprivation of the PIP 2. This work supports the importance of functional interactions between PLD and Rac in the biological response of cell migration.
Static digital telepathology: a model for diagnostic and educational support to pathologists in the developing world.

Background: The practice of pathology in the developing world presents challenges in terms of limited resources, shortages of trained personnel, and lack of continuing education programs. Telepathology holds promise as a means of diagnostic and educational support. Methods: We donated multiheaded teaching microscopes equipped with digital cameras to four hospitals in Eastern Africa and trained local pathologists on their use. Static images of challenging cases were posted on a web-based telepathology platform. A U.S.-based pathologist reviewed images in consultation with subspecialist colleagues. Results: Over a period of 40 months, 109 cases were submitted for second opinion consultation, including 29 dermatopathol- ogy cases (26.6%), 14 hematopathology cases (12.8%), and 13 cases each (11.9%) in cytopathology and bone and soft tissue pathology. Static images enabled a complete or partial diagnosis in 100/109 cases (91.7%). Factors precluding a definitive diagnosis included absence of confirmatory immunophenotyping, technical issues, or lack of clinical history. Case responses included a diagnosis and discussion, including differential diagnosis, references, and treatment recommendations. Conclusion: Static digital telepathology is a simple, cost-effective, reliable and efficient means to provide diagnostic and educational support to pathologists in the developing world. Additional training may help overcome technical factors precluding a definitive diagnosis in certain cases.
PD/SOI SRAM performance in presence of gate-to-body tunneling current

This paper presents a detailed study on the effects of gate-to-body tunneling current on partially depleted silicon-on-insulator (PD/SOI) CMOS SRAM. It is shown that the presence of gate-to-body tunneling current changes the strength of individual cell transistor in the quiescent (standby) state, thus affecting subsequent write/read operations. The degradation in the "write" performance is shown to be more significant than the degradation in the "read" performance, and the effect is more pronounced at lowered temperature. For the beneficial side, the presence of the gate-to-body tunneling current reduces the initial cycle parasitic bipolar disturb from unselected cells on the same bitline during write/read operation.
Design preference elicitation, derivative-free optimization and support vector machine search

In design preference elicitation, we seek to find individuals’ design preferences, usually through an interactive process that would need only a very small number of interactions. Such a process is akin to an optimization algorithm that operates with point values of an unknown function and converges in a small number of iterations. In this paper, we assume the existence of individual preference functions and show that the elicitation task can be translated into a derivative-free optimization (DFO) problem. Different from commonly-studied DFO formulations, we restrict the outputs to binary classes discriminating sample points with higher function values from those with lower values, to capture people’s natural way of expressing preferences through comparisons. To this end, we propose a heuristic search algorithm using support vector machines (SVM) that can locate near-optimal solutions with a limited number of iterations and a small sampling size. Early experiments with test functions show reliable performance when the function is not noisy. Further, SVM search appears promising in design preference elicitation when the dimensionality of the design variable domain is relatively high.Copyright © 2010 by ASME
Mammary epithelial cells of PR-A transgenic mice exhibit distinct alterations in gene expression and growth potential associated with transformation.

Expression of the ‘A’ and ‘B’ forms of progesterone receptor (PR), in an appropriate ratio is critical for normal mammary development. As such, mammary glands of PRA transgenic mice, carrying additional ‘A’ form of PR as transgene, exhibit morphological and histological characteristics associated with transformation. Accordingly, in the present studies, we analyzed these mammary glands for the presence of transformed epithelial cells by examining for alterations in gene expressions and growth potential, known to be associated with different stages of transformation. These studies reveal that, in the aberrant mammary epithelial structures, there is a decrease in p21 expression, an increase in cyclin D1 expression accompanied by an increase in cell proliferation, and a decrease in estrogen receptor alpha (ERα). In mammary ducts with normal histology, there is a decrease in p21 expression without an elevation in cyclin D1 expression or cell proliferation or a decrease in ERα expression. Treatment of PR-A transgenics with anti-progestin, mifepristone, has no effect on cell proliferation, cyclin D1 or ERα expression in the aberrant epithelial structures. In contrast, mifepristone restored the loss of p21 expression in the epithelial cells of both the ducts with normal histology and aberrant structures. Parallel studies reveal no apparent differences between the mammary glands of wild-type and PR-B transgenic mice, which carry additional PR ‘B’ form. Accordingly, we conclude that (i) mammary glands of PR-A transgenics contain at least two distinct populations of transformed epithelial cells, (ii) the epithelial cell population in the ducts with normal histology contain presumptive immortalized cells, indicative of early stages of transformation, (iii) the aberrant epithelial structures contain later stages of transformation associated with hyperplasias/pre-neoplasias and (iv) the transformation of mammary epithelial cells in PR-A transgenics might be due to a misregulation in progesterone action resulting from overexpression of PR ‘A’ form.
HIV-1 and HIV-2 Reverse Transcriptases: Different Mechanisms of Resistance to Nucleoside Reverse Transcriptase Inhibitors

As anti-HIV therapy becomes more widely available in developing nations, it is clear that drug resistance will continue to be a major problem. The related viruses HIV-1 and HIV-2 share many of the same resistance pathways to nucleoside reverse transcriptase inhibitors (NRTIs). However, clinical data suggest that while HIV-1 reverse transcriptase (RT) usually uses an ATP-dependent excision pathway to develop resistance to the nucleoside analog zidovudine (AZT), HIV-2 RT does not appear to use this pathway. We previously described data that suggested that wild-type (WT) HIV-2 RT has a much lower ability to excise AZT monophosphate (AZTMP) than does WT HIV-1 RT and suggested that this is the reason that HIV-2 RT more readily adopts an exclusion pathway against AZT triphosphate (AZTTP), while HIV-1 RT is better able to exploit the ATP-dependent pyrophosphorolysis mechanism. However, we have now done additional experiments, which show that while HIV-1 RT can adopt either an exclusion- or excision-based resistance mechanism against AZT, HIV-2 RT can use only the exclusion mechanism. All of our attempts to make HIV-2 RT excision competent did not produce an AZT-resistant RT but instead yielded RTs that were less able to polymerize than the WT. This suggests that the exclusion pathway is the only pathway available to HIV-2.
Xenopus Embryonic Spinal Neurons Express Potassium Channel Kvβ Subunits

Developmental regulation of voltage-dependent delayed rectifier potassium current ( I Kv) of Xenopus primary spinal neurons regulates the waveform of the action potential. I Kv undergoes a tripling in density and acceleration of it activation kinetics during the initial day of its appearance. Another voltage-dependent potassium current, the A current, is acquired during the subsequent day and contributes to further shortening of the impulse duration. To decipher the molecular mechanisms underlying this functional differentiation, we are identifying potassium channel genes expressed in the embryonic amphibian nervous system. Potassium channels consist of pore-forming (α) as well as auxiliary (β) subunits. Here, we report the primary sequence, developmental localization, and functional properties of two Xenopus Kvβ genes. On the basis of primary sequence, one of these (xKvβ2) is highly conserved with Kvβ2 genes identified in other species, whereas the other (xKvβ4) appears to identify a new member of the Kvβ family. Both are expressed in developing spinal neurons during the period of impulse maturation but in different neuronal populations. In a heterologous system, coexpression of xKvβ subunits modulates properties of potassium current that are developmentally regulated in the endogenous I Kv. Consistent with xKvβ4's unique primary sequence, the repertoire of functional effects it has on coexpressed Kv1α subunits is novel. Taken together, the results implicate auxiliary subunits in regulation of potassium current function and action potential waveforms in subpopulations of embryonic primary spinal neurons.
The Impact of Groundfish Imports on the United States Fishing Industry: An Empirical Analysis

This paper presents an economic analysis of the issue of United States-Canadian groundfish trade. Using an econometric model the parameters of consumer demand for United States domestic and imported groundfish products are estimated. The model is then used to evaluate the potential impact of countervailing duties leveled against imported fish products. It is found that while such duties would likely increase consumer prices for fish in the United States the fisherman's prices would not increase proportionately. The net protective effect to the United States harvesting sector of such tariffs thus seems minimal.
Dynamin and its Role in Membrane Fission

Dynamin, a 100-kDa GTPase, is an essential component of vesicle formation in receptor-mediated endocytosis, synaptic vesicle recycling, caveolae internalization, and possibly vesicle trafficking in and out of the Golgi. In addition to the GTPase domain, dynamin also contains a pleckstrin homology domain (PH) implicated in membrane binding, a GTPase effector domain (GED) shown to be essential for self-assembly and stimulated GTPase activity, and a C-terminal proline-rich domain (PRD), which contains several SH3-binding sites. Dynamin partners bind to the PRD and may either stimulate dynamin's GTPase activity or target dynamin to the plasma membrane. Purified dynamin readily self-assembles into rings or spirals. This striking structural property supports the hypothesis that dynamin wraps around the necks of budding vesicles where it plays a key role in membrane fission. The focus of this review is on the relationship between the GTPase and self-assembly properties of dynamin and its cellular function.
Microbial symbionts of marine invertebrates: opportunities for microbial biotechnology.

Marine invertebrates are sources of a diverse array of bioactive metabolites with great potential for development as drugs and research tools. In many cases, microorganisms are known or suspected to be the biosynthetic source of marine invertebrate natural products. The application of molecular microbiology to the study of these relationships will contribute to basic biological knowledge and facilitate biotechnological development of these valuable resources. The bryostatin-producing bryozoan B. neritina and its specific symbiont “Candidatus Endobugula sertula” constitute one promising model system. Another fertile subject for investigation is the listhistid sponges that contain numerous bioactive metabolites, some of which originate from bacterial symbionts.
Translational attenuation differentially alters the fate of disease-associated fibulin proteins

Mutations in fibulin proteins that cause cellular secretion deficiencies are linked to a variety of diseases, ranging from retinopathies to cutis laxa (CL). One secretion-deficient fibulin mutant, R345W fibulin-3, causes the macular dystrophy malattia leventinese by increased endoplasmic reticulum retention and/or extracellular misfolding. Herein, we report that small-molecule activation of the PERK arm of the unfolded protein response partially rescues R345W secretion deficiencies through translational attenuation mediated by eIF2α phosphorylation. Enhanced mutant fibulin-3 secretion can also be achieved by activation of a PERK-independent eIF2α kinase through arsenite treatment and is independent of activating transcription factor 4 signaling and protein translation. However, this translational attenuation strategy was unsuccessful for enhancing the secretion deficiencies of fibulin-5 mutants associated with age-related macular degeneration or CL. While lowered growth temperature enhanced the secretion ...
Automated Generation of Robust Error Recovery Logic in Assembly Systems Using Genetic Programming

Abstract Automated assembly lines are subject to unexpected failures, which can cause costly shutdowns. Generally, the recovery process is done “on-line” by human experts or automated error recovery logic controllers embedded in the system. However, these controller codes are programmed based on anticipated error scenarios and, due to the geometrical features of the assembly lines, there may be error cases that belong to the same anticipated type but are present in different positions, each requiring a different way to recover. Therefore, robustness must be assured in the sense of having a common recovery algorithm for similar cases during the recovery sequence. The proposed approach is based on three-dimensional geometric modeling of the assembly line coupled with the genetic programming and multi-level optimization techniques to generate robust error recovery logic in an “off-line” manner. The approach uses genetic programming's flexibility to generate recovery plans in the robot language itself. An assembly line is modeled and from the given error cases an optimum way of error recovery is investigated using multi-level optimization in a “generate and test” fashion. The obtained results showed that with the improved convergence gained by using multi-level optimization, the infrastructure is capable of finding robust error recovery algorithms. It is expected that this approach will require less time for the generation of robust error recovery logic.
Honey Ant based cooperative data accumulation in wireless sensor networks

Wireless Sensor Networks have found wide acceptance in a range of user applications, due to their ability to monitor ambient conditions without human supervision. These networks typically consist of a large number of densely deployed, low-cost, low-power, multi-functional sensor nodes that interact with each other using wireless links. Despite several limitations in their individual resources, it is well known that, cooperation among sensor nodes can result in large and powerful ad-hoc computing systems. Towards this end, we need to consider among other characteristics, the storage capacity of individual nodes as it is usually very limited, compared to the amount of data that a node generates. Limited storage capability, coupled with temporal availability of sink nodes and varying importance of collected data mean that, the generated data needs to be stored locally, in the network, for later retrieval. To achieve this, we introduce a cooperative storage mechanism that is based on the behavior of Honey Ants in the real world. The proposed technique is based on the concept of data migration and relies on migratory transportation units called Ant Agents to seek out spare storage resources within the network. Simulation results for the proposed model demonstrate that cooperative data accumulation is indeed beneficial for storage constrained nodes in wireless sensor networks.
Fuzziness of Inclusion/Exclusion in Networks

This article addresses the concept of fuzziness of inclusion/exclusion in networks. It argues that the conceptualization of inclusion/exclusion is more complex than a static, binary dichotomy of in/out and requires that we take a viewpoint that examines the changes in the dynamics of power among the stakeholders. With this viewpoint we begin to examine the balance of power between gatekeepers and gated (the entity subjected to gatekeeping). The power dynamics are manifest through processes by which transient elites (gatekeepers) emerge and mature. Contrary to traditional thinking about gatekeepers controlling the whole process, we argue that the collective patterns of behavior of the gated have a crucial role in the emergence and sustainability of gatekeepers. Fuzziness is essential to the dynamics of these processes. Fuzziness from a Bird’s Eye View This article discusses how the power dynamics among stakeholders in networks are changing. Essential to understanding these changes is the concept of fuzziness of inclusion/exclusion in networks. Fuzziness is defined as ambiguity about, and uncertainty of, an entity being “in” or “out” of a network. The fuzziness is caused by new processes by which the gated designate (crown) gatekeepers who act as transient elites, actors of transient empowerment and domination. Once the gated (and the gates) have determined the gatekeepers, the latter control these gates and the structure of the network in an attempt 1
Qualification of Polyimide Based Coverlays for 900 MHz and 2.40 GHz Microstrip Antenna Applications

Organic coverlays are required to protect microstrip circuits in most applications. The presence of coverlay can potentially influence the performance of microstrip antennas. This paper describes the qualification of polyimide based coverlays for microstrip antennas both in 900 MHz and 2.50 GHz frequency bands. An Inverted F-shaped antenna fabricated on FR-4 dielectric is used as the test vehicle and two different coverlay materials are tested with respect to key parameters like resonant frequency, S11 bandwidth, antenna gain, frequency detuning, and radiation pattern. The data presented in this paper clearly indicates polyimide materials are well suited to cover microstrip antenna circuits with minimal impact on performance.
Brachytherapy-based Accelerated Partial Breast Irradiation Provides Equivalent 10-Year Outcomes to Whole Breast Irradiation: A Matched-Pair Analysis.

Introduction:Although whole breast irradiation (WBI) represents the standard radiotherapy technique in breast conserving therapy, accelerated partial breast irradiation (APBI) has emerged as an option to reduce treatment duration with comparable clinical outcomes. The purpose of this analysis is to
Thermal and Mechanical Modeling of Metal Foams for Thermal Interface Application

We present a study on the apparent thermal resistance of metal foams as a thermal interface in electronics cooling applications. Metal foams are considered beneficial for several applications due to its significantly large surface area for a given volume. Porous heat sinks made of aluminum foam have been well studied in the past. It is not only cost effective due to the unique production process but also appealing for the theoretical modeling study to determine the performance. Instead of allowing the refrigerant flow through the open cell porous medium, we instead consider the foam as a thermal conductive network for thermal interfaces. The porous structure of metal foams is moderately compliant providing a good contact and a lower thermal resistance. We consider foam filled with stagnant air. The major heat transport is through the metal struts connecting the two interfaces with high thermally conductive paths. We study the effect of both porosity and pore density on the observed thermal resistance. Lower porosity and lower pore density yield smaller bulk thermal resistance but also make the metal foam stiffer. To understand this tradeoff and find the optimum, we developed analytic models to predict intrinsic thermal resistance as well as the contact thermal resistance based on microdeformation at the contact surfaces. The variants of these geometries are also analyzed to achieve an optimum design corresponding to maximum compliance. Experiments are carried out in accordance with ASTM D5470 standard. A thermal resistance between the range 17 and 5 K cm2/W is observed for a 0.125 in. thick foam sample tested over a pressure range of 1–3 MPa. The results verify the calculation based on the model consisting the intrinsic thermal conductivity and the correlation of constriction resistance to the actual area of contact. The area of contact is evaluated analytically as a function of pore size (5–40 PPI), porosity (0.88–0.95), orientation of struts, and the cut plane location of idealized tetrakaidecahedron (TKDH) structure. The model is developed based on assumptions of elastic deformations and TKDH structures which are applicable in the high porosity range of 0.85–0.95. An optimum value of porosity for minimizing the overall interface thermal resistance was determined with the model and experimentally validated.
Examining the Influence of Team Project Design Decisions on Student Perceptions and Evaluations of Instructors

Although there is an increasing focus on the importance of incorporating team projects into business curricula, the way team projects are implemented varies significantly among instructors. Student...
Heterophile Antibodies Developed During Prophylactic Rabies Immunization

SummaryHeterophmc antibodies developed during rabies-immunization differ from the heterophilic antibody developed in true serum sickness and from the heterophilic antibodies present in cases of infectious mononucleosis.
The Anatomy and Histology of the Proventriculus of Ips Radiatae Hopkins (Coleoptera: Scolytidae)

Ips radiatae Hopkins is one of the minor species of a large group of bark beetles commonly found in coniferous trees. It breeds under the bark of various species of pine, notably in weakened and recently felled Monterey pine ( Pinus radiata D. Don.)—a non-commercial tree species native to the coastal region of California. Although not economically important, Ips radiatae is probably anatomically similar to the better known and more destructive members of the genus. This report of investigations on the anatomy and histology of the proventriculus of the adult bark beetle is therefore presented with the expectation that it will be of interest in connection with similar studies on other species.
Pediatric Hospitalist Co-Management of Surgical Patients Improves Safety Outcomes

Pediatric inpatient units care for increasing proportions of medically complex surgical patients at risk for adverse events. Hospitalist surgical co-management has been identified as a potential safety strategy to decrease this risk. We sought to determine the impact of a pediatric hospitalist co-management program on length of stay (LOS), mortality, and medical errors. This retrospective cross-sectional study compared patients who received hospitalist co-management from 2005-2012, with historical control patients admitted to the surgical services from 2000-2005 at the Johns Hopkins …
Oral ganciclovir for patients with cytomegalovirus retinitis treated with a ganciclovir implant

Background The intraocular ganciclovir implant is effective for local treatment of cytomegalovirus retinitis in patients with the acquired immunodeficiency syndrome (AIDS), but it does not treat or prevent other systemic manifestations of cytomegalovirus infection. Methods Three hundred seventy-seven patients with AIDS and unilateral cytomegalovirus retinitis were randomly assigned to one of three treatments: a ganciclovir implant plus oral ganciclovir (4.5 g daily), a ganciclovir implant plus oral placebo, or intravenous ganciclovir alone. The primary outcome measure was the development of new cytomegalovirus disease, either contralateral retinitis or biopsy-proved extraocular disease. Results The incidence of new cytomegalovirus disease at six months was 44.3 percent in the group assigned to the ganciclovir implant plus placebo, as compared with 24.3 percent in the group assigned to the ganciclovir implant plus oral ganciclovir (P=0.002) and 19.6 percent in the group assigned to intravenous ganciclovir ...
Post-Packaged Measurement of MEMS Gap, Displacement, Force, Stiffness, Mass, Damping, and Quality Factor

What is presented: We present a practical MEMS metrology technology that can be used to extract system stiffness, mass, damping, and excitation force after a MEMS is packaged. Presently the technology applies to planar MEMS with comb drives. Our method is quick, accurate, and precise. Why important: Our technology will likely be important for manufacture, accuracy, and controllability. During manufacture, MEMS metrology can be 30% to 40% of the cost. This high cost is due to factory testing tools that are impractical and not optimized for batch fabrication. The tools often apply an external disturbance that the MEMS are electronically tuned to. Accuracy is a critical problem area in MEMS. Often MEMS are more sensitive and precise than the tools used to calibrate them. And there are no ASTM standards in MEMS for measuring stiffness, mass, damping, and force. Since there is a lack of standards, high cost in metrology, and low return on measurement due to large uncertainties, it has been difficult for manufa...
Titanium in biotite from metapelitic rocks: Temperature effects, crystal-chemical controls, and petrologic applications

An extensive natural biotite data set from western Maine constrains the temperature and crystal-chemical controls on the saturation Ti levels in biotites from metapelites. The geologically and petrologically well-characterized metamorphic terrain associated with the M3 metamorphism of the Acadian Orogeny of western Maine is ideal for this approach in that metamorphism occurred at roughly isobaric conditions of 3.3 kbar, and chemical equilibrium was closely approached. The data set from these metapelites exhibits systematic variations in Ti contents over a continuum of metamorphic grades (garnet through sillimanite-K-feldspar zones), mineral assemblages, and bulk compositional ranges. Samples were selected so that competing substitutions are restricted to those in metapelites with quartz, aluminous phases (chlorite, staurolite, or sillimanite), Ti phases (ilmenite or rutile), and graphite. Due to crystal-chemical factors, in any given metamorphic zone, an inverse linear relationship exists between Ti and Mg contents. Decreasing octahedral Ti and increasing tetrahedral Si in Mg-rich biotite helps alleviate size disparity between octahedral and tetrahedral sheets. For a biotite with a given Mg content, Ti most dramatically increases above staurolite zone conditions. Our constrained data set allows us to calculate a Ti saturation surface for natural biotite as a function of temperature and Mg content at 3.3 kbar. The Ti saturation surface can be used to establish several important metamorphic features in similar metamorphic settings. These include a general approach to equilibrium, local and/or subtle departures from equilibrium due to minor alteration to chlorite, and relative and absolute geothermometry based on Ti in biotite inclusions in refractory minerals and in matrix biotite.
The National Ambulatory Medical Care Survey: PAs and NPs in outpatient surgery

ABSTRACTBackground:This study aimed to determine the prevalence and occupational characteristics of physician assistants (PAs) and nurse practitioners (NPs) in outpatient surgical subspecialty clinics.Methods:The 2007 and 2008 National Ambulatory Medical Care Survey (NAMCS) databases were queried fo