cssi/SciSciGPT-SciSciNet huggingface dataset:
Toxins that affect voltage-dependent calcium channels.

At this time, there are five potential candidates for calcium channel specific toxins. All five of these toxins appear to affect the function of voltage-dependent calcium channels. Atrotoxin, beta-leptinotarsin-h and maitotoxin activate channels, whereas both taicatoxin and omega-conotoxin are inhibitors. Neither maitotoxin nor omega-conotoxin alters the binding of dihydropyridines to membranes derived from the cells upon which the toxins exert their effects. In contrast, both atrotoxin and taicatoxin inhibit the binding of dihydropyridines to ventricular membranes. It is not currently known whether beta-leptinotarsin-h affects the binding. The effects of maitotoxin and atrotoxin are blocked by dihydropyridines and verapamil. Direct binding studies with radiolabeled toxins have been performed only with omega-conotoxin, and the binding site density for this toxin appears to be at least one order of magnitude greater than the density of dihydropyridine binding sites in synaptosomes. Studies to examine the third and fourth criteria which we have listed (i.e. that the effects are not via a second messenger, or an enzyme activity) have not been reported for either beta-leptinotarsin-h or omega-conotoxin. Atrotoxin and taicatoxin, added outside a patch pipette, have no effects on calcium channels within the patch and are, therefore, probably not affecting calcium channels via a second messenger. Maitotoxin, however, affects the formation of inositol phosphates and, hence, could be affecting the channel indirectly. The fractions containing the toxic components atrotoxin and taicatoxin have no phospholipase or protease activity, and this is presumably true also for omega-conotoxin since it has been purified to homogeneity. Although all of the toxins have the potential to be important tools with which to study calcium channel structure and function, a number of experiments remain to be done in order to establish conclusively that these five toxins bind specifically to the voltage-dependent calcium channel. In conclusion, we would like to briefly mention why so much effort is being devoted to the search for these calcium channel specific toxins. Such a toxin would provide a very valuable tool in the study of calcium channels for a number of reasons. First, the toxin would be another ligand for the channel and, as such, would provide an alternative to organic ligands such as the dihydropyridines which are lipophilic and, in many tissues, have more than one binding site.(ABSTRACT TRUNCATED AT 400 WORDS)
Thin film surface treatments for lowering dust adhesion on Mars Rover calibration targets

The current generation of calibration targets on Mars Rover serve as a color and radiometric reference for the panoramic camera. They consist of a transparent silicon-based polymer tinted with either color or grey-scale pigments and cast with a microscopically rough Lambertian surface for a diffuse reflectance pattern. This material has successfully withstood the harsh conditions existent on Mars. However, the inherent roughness of the Lambertian surface (relative to the particle size of the Martian airborne dust) and the tackiness of the polymer in the calibration targets has led to a serious dust accumulation problem. In this work, non-invasive thin film technology was successfully implemented in the design of future generation calibration targets leading to significant reduction of dust adhesion and capture. The new design consists of a μm-thick interfacial layer capped with a nm-thick optically transparent layer of pure metal. The combination of these two additional layers is effective in burying the relatively rough Lambertian surface while maintaining diffuse properties of the samples which is central to the correct operation as calibration targets. A set of these targets are scheduled for flight on the Mars Phoenix mission.
Zinc(II) complexation with bis(1,4,7-triazacyclononane) ligands containing polymethylene linker groups. An equilibrium and structural study

Abstract The stoichiometry and stability of a series of zinc(II) complexes of bis(1,4,7-triazacyclononane) ligands containing from two- to eight-membered polymethylene bridging chains have been studied by pH potentiometry. Equilibrium modeling of the data indicates that stable 1:1 complexes form when the linker group contains only two or three C atoms. Ligands comprising longer bridging chains form stable 1:1 and 2:1 Zn(II)–L complexes. The stability trends observed for the 1:1 complexes follow those of the Cu(II) complexes where the ligands with the shorter bridging groups form the most stable 1:1 complexes. The 2:1 complexes show virtually no variation in stability throughout the series. The X-ray structures of two monomeric complexes, [Zn(EM2)][ZnCl3ONO2] (1) and [Zn(EM3)][ZnBr4] (2), and a dimeric complex, [Zn2(EM5)(μ-Cl)3]2(ClO4)2·4H2O (3), containing a face shared bioctahedral Zn(μ-Cl)3Zn cluster are determined. The structure of the [ZnCl3ONO2]2− anion has not previously been reported.
Validating a DEA-based menu analysis model using structural equation modeling

Abstract While a restaurant's menu is known as the cornerstone of the operation, research aimed at optimizing it has not radically evolved. This is problematic in that traditional menu management and analysis models share the common and irremediable shortcoming of variable interdependency, in which the central intersection between vectors in a matrix is dictated by the means for the associated variables. In other words, changes to a single menu item alter the means of the related variables and artificially alter the position of other menu items. Moreover, the limited number of inputs, which typically ignore labor and labor costs, casts suspicion on any conclusions that are drawn. More recent models, such as those that integrate non-parametric statistics including data envelopment analysis (DEA), promise greater utility but have gone largely untested. This paper extends the more holistic model made possible by applying DEA and then tests the resulting archetype using structural equation modeling (SEM). The results suggest that DEA models are valid and that even more complex models are possible. For managers, the findings illustrate the inadequacy of earlier, simplistic models and call for a broader understanding of menu optimization approaches.
Infrared reflection–absorption properties of platinum nanoparticle films on metal electrode substrates: control of anomalous optical effects

Abstract A simple method is described for preparing ultrathin films of carbon-supported platinum nanoparticles on gold and other substrates for examination by electrochemical infrared reflection–absorption spectroscopy (EC-IRAS) in which the anomalous “anti-absorbance” properties commonly observed for metal particle arrays can be minimized as well as controlled. The tactic involves physical deposition as an aqueous suspension, followed by drying and thorough rinsing. The Pt monolayer-level films prepared by this means exhibit largely positive unipolar absorbance bands for CO adlayers, whereas an anomalous inverted band component appears for thicker films, especially those featuring high Pt nanoparticle loadings. These findings demonstrate the value of the film preparation tactic for exploring the electrocatalytic properties of C/Pt materials by using combined electrochemical and EC-IRAS measurements.
Role of Fixed Coefficients and Exponents in the Prediction of Human Drug Clearance: How Accurate are the Predictions from One or Two Species?

Pharmacokinetic (PK) interspecies scaling is generally conducted using PK data from at least three animal species but three animal species may not be always available. In a recent manuscript, Tang et al. have described the methods to predict human drug clearance using one or two animal species. The authors claim that their proposed methods are better than the rule of exponents (ROE) which uses at least three animal species for the prediction of human drug clearance. A thorough examination of Tang et al.'s manuscript indicates that the data analysis may not be accurate. Considering that Tang et al.'s method may be of value, the objective of this study was to extend Tang et al.'s proposed methods for drugs given both intravenously and orally. The results of this study indicate that human drug clearance cannot be predicted with reasonable accuracy for most of the drugs by Tang et al.'s proposed methods and the accuracy of the prediction obtained from the ROE remains more accurate (based on average fold-error) than the one or two-species methods. This manuscript also clarifies some incorrect views regarding ROE presented by Tang et al. in their manuscript.
An insider's view

It is no accident that Earth scientists devote so much attention to the parts of our planet that are nearby. The data are voluminous, the supporting experiments are easier and the issues are well-defined, pressing and still often unresolved. The deep interior, and especially the core, has usually been most attractive to those who like their science unencumbered by too many awkward facts or richness of detail.
Fractional Reserve Banking, Client Collaboration, and Fraud

This paper traces the recent debate over the legitimacy of maturity mismatching and fractional reserve banking. It shows that there is common ground between Bagus and Howden (Journal of Business Ethics, 90(3):399–406, 2009, 106:295–300, 2012) on the one hand and Evans (Journal of Business Ethics, 2013) on the other regarding contractual arrangements that lead to fractional reserve banking, while both agree that fractional reserve banking that arises out of a bailment or storage contract constitutes fraud. Block and Barnett (Journal of Business Ethics, 88(4):711–716, 2009, 100:229–238, 2011) stress the illegitimacy of fractional reserve banking for creating more money substitutes than there is actual money. While it is true that fractional reserve banks are capable of creating money, this activity still cannot be regarded as fraudulent using a common law definition of fraud for it can only take place with requisite client collaboration that makes it impossible to identify a victim.
Effect of molecular weight of amine end-modified poly(β-amino ester)s on gene delivery efficiency and toxicity

Amine end-modified poly(β-amino ester)s (PBAEs) have generated interest as efficient, biodegradable polymeric carriers for plasmid DNA (pDNA). For cationic, non-degradable polymers, such as polyethylenimine (PEI), the polymer molecular weight (MW) and molecular weight distribution (MWD) significantly affect transfection activity and cytotoxicity. The effect of MW on DNA transfection activity for PBAEs has been less well studied. We applied two strategies to obtain amine end-modified PBAEs varying in MW. In one approach, we synthesized four amine end-modified PBAEs with each at 15 different monomer molar ratios, and observed that polymers of intermediate length mediated optimal DNA transfection in HeLa cells. Biophysical characterization of these feed ratio variants suggested that optimal performance was related to higher DNA complexation efficiency and smaller nanoparticle size, but not to nanoparticle charge. In a second approach, we used preparative size exclusion chromatography (SEC) to obtain well-defined, monodisperse polymer fractions. We observed that the transfection activities of size-fractionated PBAEs generally increased with MW, a trend that was weakly associated with an increase in DNA binding efficiency. Furthermore, this approach allowed for the isolation of polymer fractions with greater transfection potency than the starting material. For researchers working with gene delivery polymers synthesized by step-growth polymerization, our data highlight the potentially broad utility of preparative SEC to isolate monodisperse polymers with improved properties. Overall, these results help to elucidate the influence of polymer MWD on nucleic acid delivery and provide insight toward the rational design of next-generation materials for gene therapy.
Saw-tooth refractive lens for high energy x-ray focusing

Saw-tooth refractive lens (SRL) provides a comparatively attractive option for X-ray focusing. An SRL assembly consists of two parts, each with an array of triangular structures (prisms), set tilted symmetrically with respect to the incoming beam. Its main advantage is a simple, continuous tunability in energy and focal length. SRLs can be used for both long and short focal length focusing. Long focal distance focusing of an SRL can accurately be predicted using simple analytical relations. However, the focus size at short focal distances focusing may deviate appreciably from the expected demagnified source size when: (1) the length of the SRL is comparable with the focusing distance, (2) the incident beam is not monochromatic, and (3) and the distance between adjacent prism tips, the tip step, is large . The first factor was considered in a previous work while the other two are addressed is this paper. This preliminary work is aimed at a better understanding of the SRL lenses for focusing an undulator beamline at the Advanced Photon Source (APS).
Abstract 729: Norleual a hepatocyte growth factor/c-Met inhibitor blocks malignant phenotypes in cancerous cells

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA The primary purpose of this study was to demonstrate that the hepatocyte growth factor (HGF) antagonist norleual is capable of attenuating the cellular responses of cancer cells to HGF. The angiotensin IV analog norleual [Nle-Tyr-Ile-ψ-(CH2-NH2)3-4-His-Pro-Phe] exhibits structural homology with the hinge (linker) region of HGF and acts to block HGF dimerization, a process required for its activation. Norleual competitively inhibited the binding of a H3-Hinge peptide sequence to the HGF, and binds directly to HGF with a Ki = 3.6x10-12M. Predictably, norleulal is able to block the cellular responses due to HGF activation in multiple cell types at concentrations in the picomolar range including HGF/c-Met sensitive pancreatic cancer cells. Norleual's ability to inhibit the growth and survival of several cell lines including pancreatic cancer cells was evaluated using viability testing and cell sorting tags to identify living, dead and apoptotic cells. HGF/c-Met activation increases the invasive potential of the pancreatic cancer cells, which provides a mechanistic basis for the ability of c-Met to support pancreatic tumor metastasis. In this regard norleual as an HGF antagonist was able to block the migration and invasion of cancer cells through collagen gels in a transwell chamber. Over-activation of the growth factor system HGF/c-Met is a critical contributor to cancer's ability to disseminate rapidly and its refractoriness to standard chemotherapy. Norleual, which is a representative of a “first-in-class” group of molecules that blocks the activation step of HGF, represent a novel therapeutic approach to the treatment of HGF/Met sensitive cancers including pancreatic cancer. Citation Format: Leen H. Kawas, Kevin J. Church, Malte Lange, Michelle Mcmicheal, Brent Yamamoto, Joseph W. Harding. Norleual a hepatocyte growth factor/c-Met inhibitor blocks malignant phenotypes in cancerous cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 729. doi:10.1158/1538-7445.AM2014-729
Cloned poliovirus complementary DNA is infectious in mammalian cells

A complete, cloned complementary DNA copy of the RNA genome of poliovirus was constructed in the Pst I site of the bacterial plasmid pBR322. Cultured mammalian cells transfected with this hybrid plasmid produced infectious poliovirus. Cells transfected with a plasmid which lacked the first 115 bases of the poliovirus genome did not produce virus.
Solution structure of a small protein containing a fluorinated side chain in the core.

We report the first high-resolution structure for a protein containing a fluorinated side chain. Recently we carried out a systematic evaluation of phenylalanine to pentafluorophenylalanine (Phe → F5-Phe) mutants for the 35-residue chicken villin headpiece subdomain (c-VHP), the hydrophobic core of which features a cluster of three Phe side chains (residues 6, 10, and 17). Phe → F5-Phe mutations are interesting because aryl–perfluoroaryl interactions of optimal geometry are intrinsically more favorable than either aryl–aryl or perfluoroaryl–perfluoroaryl interactions, and because perfluoroaryl units are more hydrophobic than are analogous aryl units. Only one mutation, Phe10 → F5-Phe, was found to provide enhanced tertiary structural stability relative to the native core (by ∼1 kcal/mol, according to guanidinium chloride denaturation studies). The NMR structure of this mutant, described here, reveals very little variation in backbone conformation or side chain packing relative to the wild type. Thus, although Phe → F5-Phe mutations offer the possibility of greater tertiary structural stability from side chain–side chain attraction and/or side chain desolvation, the constraints associated with the native c-VHP fold apparently prevent the modified polypeptide from taking advantage of this possibility. Our findings are important because they complement several studies that have shown that fluorination of saturated side chain carbon atoms can provide enhanced conformational stability.
Lack of Correlation Between Microvascular Density and Pathological Features and Outcomes in Sinonasal and Oral Mucosal Melanomas

Unlike its cutaneous counterpart, prognostic markers for primary mucosal malignant melanoma have not been well elucidated. It has been recently demonstrated that microvascular density (MVD) in cutaneous malignant melanoma has a significant negative correlation with survival; however, this has not been well-studied in mucosal malignant melanoma of the head and neck. This study explores the potential association between MVD, various histological parameters, and the outcome of a series of sinonasal and oral mucosal melanomas. Nineteen such cases were immunostained with CD31 and the MVD was calculated by using Bioquant Image Analysis Software (R and M Biometrics, Nashville, TN). These cases included 16 sinonasal and 3 oral cavity tumors. The 1, 2, 3, 4 and 5 years overall survival rates were 75, 57, 61, 46 and 46%, respectively. The MVD of the tumors ranged from 25.7 to 732 vessels/mm2 (mean 142.8 vessels/mm2; median 84.7 vessels/mm2). There was no significant correlation between the MVD and the different clinicopathological features seen within the tumors. There was also no correlation between the MVD and relapse free and overall survival. The results of this study suggest that MVD does not correlate with outcome in mucosal melanoma of the head and neck as seen in cutaneous melanomas. Further larger studies are needed to identify predictive and prognostic markers in such melanomas.
Asymptomatic wide complex tachycardia: a case report

Wide complex tachycardias are a commonly encountered entity in coronary care units, intensive care units and emergency departments. Though, these arrhythmias are potentially fatal, they need to recognized first and treated appropriately. Associated physical signs are helpful in this. We present a case of a 54-year-old-female who recently underwent placement of an implantable cardioverter-defibrillator for cardiomyopathy and developed tachycardia.
Non-Steady-State Creep Behavior in Tube Gas Forming

A steady-state creep equation is commonly used in the analysis of superplastic forming or other elevated temperature forming processes. However, in Hot Metal Gas Forming of tubes, the effective stress increases as tube diameter expands and wall thickness decreases, and a steady-state creep condition does not exist. Thus, non-steady-state creep behavior of materials becomes important. This paper presents some experimental results on transient creep behavior of a magnesium alloy, and provides an analysis on transient creep behavior and its application in tube forming mechanics. It is verified that non-steady-state creep plays important role in the gas tube forming at elevated temperatures.
Membrane transport by macrophages in suspension and adherent to glass

We have compared membrane transport of lysine and adenosine by rabbit lung macrophages in suspension and adherent to glass cover slips. The rapid sampling techniques employed permitted measurements to be made over intervals as short as 10 seconds. Suspended cells transported both nutrients at a faster rate, although the Km values for the two transport systems remained unchanged. Colchicine, cytochalasin B and adenosine did not interfere with the enhancement.
Some Children See Him ...: Political Participation and the Black Christ

This paper explores the role that membership in a politicized church and believing in a black Christ have on the political mobilization and participation of African Americans. Using data from the 1993–94 National Black Politics Study (NBPS), the authors conclude that imagining a black Christ is a radicalizing force on political participation. Hearing politicizing messages in a place of worship and believing that Christ is black appears to shift African Americans from relatively conservative or traditional forms of political participation, such as contacting officials, to more non-traditional political protest. Further, it appears that imagining a black Christ is distinct from other aspects of a racial belief system and while it has political implications, it clearly has religious roots that separate it from other racial beliefs.
Pastoral Nomadism and Tribal Power

The nomadic tribes of Iran have long attracted interest, yet despite many descriptive accounts there have been few critical studies of them. Major obstacles to analysis have been a romanticization of nomadism, a dichotomization that emphasizes the differences between nomadism and agriculture, and a disregard for the historical setting and change. Discussions have tended to obscure important economic and social relationships between nomadic and sedentary society, and within the tribal structure itself; moreover, it has often been assumed that an organic or deterministic, link between pastoralitm and tribal political structures exists.
Repeat triage in disaster relief: Questions from Haiti

During a mass casualty disaster, the acute imbalance between need for treatment and capacity to supply care poses difficult rationing problems. It is common to assume that such disasters call for "utilitarian" procedures that deliberately prioritize saving the most lives over other considerations. A group of medical responders to the 2010 Haitian earthquake faced particular challenges in determining how to allocate limited treatment, time and other resources between existing patients and potential patients not yet under care. We identified that rationing dilemmas points occurred at three points: when care had to be limited, when care had to be completed prematurely, and when care had to be withdrawn. "Repeat triage" refers to rationing challenges occurring at all these points, where the allocation of care is between existing and potential patients. By contrast, "initial triage" designates the allocation of access to treatment among new arrivals, all of whom are potential patients. Repeat and initial triage differ significantly. Several considerations make repeat triage special by supporting limited priority to existing patients, in transgression of pure "utilitarian" procedures: (1) Pragmatically, often it is more efficient to complete treatment on existing patients, for whom prognosis can be established with greater certainty and without added time, than to attempt to save new patients; (2) A fiduciary trust relationship has been formed between care-giver and existing patients, which may make the moral obligation towards them somewhat stronger than the one to potential patients; (3) Existing patients will have often arrived earlier, so when needs are equal, the "first come, first served" principle prioritizes them for care; (4) Withdrawal of care during repeat triage may constitute active rather than passive harm, and more often a serious transgression of patient autonomy; (5) Health providers should normally not be asked to behave in ways that profoundly violate their personal and professional integrity, and abandoning existing patients may do so. For these reasons, responders can permissibly give a degree of priority to existing patients over newcomers in disaster.
Lattice Trapping of Cracks in Fe Using an Interatomic Potential Derived from Experimental Data and Ab Initio Calculations

A recent approach which combines first-principles and experimental data to produce highly accurate and reliable interatomic potentials is tested for the case of bcc and fcc Fe. The Embedded-Atom-like potential accurately reproduces the basic equilibrium properties of bcc Fe, including elastic constants, phonon properties, and vacancy formation energies, as well as the correct relative stability of structures with coordination numbers ranging from 12 to 4. This potential was used in a simulation study of lattice trapping effects during the cleavage fracture of bcc Fe. A strong directional anisotropy for crack propagation was observed due to lattice trapping effects. The strongest trapping effects were observed for cleavage along the 110 planes and it was found that lattice trapping strongly favors cleavage along the 100 planes.
The collisional drift mode in a partly-ionized plasma

The structure of the drift instability was examined in several density regimes. Let sub e be the total electron mean free path, k sub z the wave-vector component along the magnetic field, and the ratio of perpendicular ion diffusion to parallel electron streaming rates. At low densities (k sub z lambda 1) the drift mode is isothermal and should be treated kineticly. In the finite heat conduction regime square root of m/M k sub z Lambda sub 1) the drift instability threshold is reduced at low densities and increased at high densities as compared to the isothermal threshold. Finally, in the energy transfer limit (k sub z kambda sub e square root of m/M) the drift instability behaves adiabatically in a fully ionized plasma and isothermally in a partially ionized plasma for an ion-neutral to Coulomb collision frequency ratio.
THEORY OF LAMINAR COLLISIONLESS SHOCKS.

A theory is derived which qualitatively and quantitatively explains the similarity between numerical simulations for electrostatic and perpendicular magnetic collisionless shocks for zero ion temperature and no anomalous resistance.
Migrating Alone or Rejoining the Family? Implications of Migration Strategies and Family Separations for Latino Adolescents

This qualitative study examined how adolescent migrants experience family separations following two different migration strategies: migrating to reunify with the family (serial migration) versus migrating alone as an adolescent (independent adolescent migration). Participants were 30 immigrant adolescents, ages 14 to 19 residing in the United States between 3 months to 7 years. For serial migrants, surrogate caregivers played an important role in normalizing their separation from their parents, although they experienced difficulty during reunification. Independent adolescent migrants accounts highlighted their adaptation to work, school, and changes in their family roles and obligations.
Receptors for pituitary adenylate cyclase-activating polypeptide Comparison with vasoactive intestinal peptide receptors

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a new member of the secretin glucagon-vasoactive intestinal peptide (VIP) family of peptides, being most homologous to VIP. PACAP exists in two amidated forms with 38 residues (PACAP38) and 27 residues (PACAP27), respectively. PACAP38 is the major form in tissues. There are two types of high-affinity receptors for PACAP: type I, which specifically binds to both PACAPs, and type II, which is shared with VIP. Type I PACAP receptors appear to have two subtypes: type IA, which binds to both PACAP38 and PACAP27, with slight preference for the latter, and type IB, with greater preference for PACAP38. Distribution of the type I PACAP receptor is different from that of VIP, and it is found in high concentrations in brain, spinal cord, anterior pituitary, adrenal medulla, spermatogonia at certain stages, mature spermatozoa, and some cell lines. Type II PACAP receptors are found in lung, liver, intestine, and other tissues, and their distribution is similar to that of the VIP receptor. Type II PACAP receptor might be similar to or identical with the VIP receptor.
Panel estimates of a two‐tiered earnings frontier

This paper uses panel data to estimate a two-tiered instead of a one-tiered frontier model. The innovation is to develop a two-step maximum likelihood procedure yielding consistent estimates of inefficiency, while at the same time accounting for heterogeneity. The model is applied by estimating a ‘two-tiered’ earnings function to obtain indices of worker and firm incomplete labour market wage information using panel data from the Panel Study of Income Dynamics (1969–84). The estimation preserves the traditional quadratic age-earnings profile, but measures the extent to which employers often pay more than necessary to hire a worker (incomplete employer information), while at the same time, employees often accept wages less than they could otherwise command (incomplete employee information). The results indicate that employees acquire less information than employers. © 1996 John Wiley & Sons, Ltd.
Analysis of the Scale Effect for Microscale Machine Tools

Miniaturization of conventional machine tools has been initiated due to inherent technical and economical advantages. To support further development in this area, a systematic design scheme must be developed on a quantitative basis to reduce the subjective design of miniaturized machine tools. The present work is the size optimization of the miniaturized milling machine on the basis of the proposed design strategy. This design strategy includes individual mathematical computations of key parameters such as volumetric error, machine working space, static, thermal, and dynamic stiffness. This mathematical modeling is established by using analytical methods followed by experimental validation. Individual computations based on the mathematical modeling are carried out to produce the penalty function of the miniaturized milling machine which is then used to find out the optimal dimension. In addition to this, the sensitivity of weighing factors is discussed to find out which weighing factor is more effective to an optimal solution. This study will eventually contribute to the development of more precise miniaturized machine tools.Copyright © 2007 by ASME
The importance of mechanical twinning in the stress-strain behavior of swaged high purity fine-grained titanium below 424°K

Zone-refined iodide titanium specimens, swaged and annealed at different temperatures to give a range of grain sizes from 2.4 to 22 μ, were deformed to fracture between 77° and 424°K. A metallographic study of the fractured specimens revealed that mechanical twinning is an important factor in the plastic deformation of this grade of titanium at subambient temperatures. In all cases, the volume fraction of twins increased steadily with strain as well as with decreasing deformation temperature. At 77°K and at a grain size of 22 μ, the twin volume fraction was greater than 0.5 at a strain of 0.5. Furthermore, each of the 77°K stress-strain curves showed a linear work-hardening character with an associated high ductility similar to that originally reported by Wasilewski for commercial purity titanium. The nearly linear stress-strain curve in this latter case has been rationalized earlier in terms of deformation twinning. The present results are in good agreement with this point of view.
Benefits of prophylactic continuous infusion of furosemide after the maze procedure for atrial fibrillation

Abstract Objectives: One of the most significant complications seen after the maze procedure for atrial fibrillation is excessive fluid retention, with subsequent pulmonary complications. To address this problem we recently started treating all patients prophylactically with a continuous infusion of furosemide starting immediately after the operation. Methods: Seventy-five consecutive patients with statistically similar demographic characteristics were divided into two groups. In the continuous infusion group (n = 36) furosemide was given intravenously as a continuous infusion at a dose of 2 to 15 mg/h for the first 48 hours after the operation, and in the bolus dose group (n = 39) furosemide was administered in bolus doses (50-100 mg) to maintain a targeted daily urinary output of 25 to 50 mL/kg. Hemodynamic data, urinary output, fluid balance, daily weights, and pulmonary complications were recorded during the first 48 hours after the operation. Results: The mean postoperative urinary output was higher, the total furosemide dose was lower, and the pulmonary complications were fewer in the continuous infusion group than in the bolus dose group. Three patients in the bolus dose group were reintubated after the operation, whereas none in the continuous infusion group were reintubated. Supplemental oxygen requirements were greater in the bolus dose group (7 vs 4 patients, P P Conclusion: Despite a smaller total dose relative to bolus infusion, prophylactic continuous furosemide infusion decreased the adverse pulmonary complications associated with excessive fluid retention in patients undergoing the maze procedure for atrial fibrillation.
Mixed culture enrichment of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica, and Yersinia enterocolitica

Abstract Rapid methods for testing foods for the presence of pathogenic bacteria typically suffer from poor sensitivity and therefore require large concentrations of the bacteria to be present for detection. Food contaminated with pathogenic bacteria may often contain only a very small number of the microorganisms making their direct detection very challenging even with existing state-of-the-art methods. Therefore prior to detection, it may be of pertinence to increase the number of potentially present pathogenic bacteria through growth in an appropriate culture medium. Furthermore, multiplexed testing for the presence of different bacteria in food samples necessitates the ability to simultaneously increase, through growth/culture, the concentration of each targeted bacterial pathogen to a detectable level. We have evaluated several commercially available and custom media preparations for their ability to support the simultaneous growth of the following bacteria: Escherichia coli O157:H7, Listeria monocytogenes , Salmonella enterica , and Yersinia enterocolitica . Growth conditions (primarily enrichment media formulation and incubation temperature) that resulted in multiplication of all four pathogens to ca. 1 × 10 5 cells/mL within 24 h or less were considered sufficient as a culture enrichment step prior to testing with most rapid methods. Axenic culture enrichment of all the bacteria for 18 h readily yielded concentrations significantly greater than 1 × 10 5 cells/mL for each of 5 different growth media. Mixed culture enrichment of the bacteria in pristine culture media and ground pork slurries indicated that several of the tested conditions appeared to be suitable for the growth of the selected bacteria to the targeted detection level, with the exception of L. monocytogenes in the ground meat (inoculated at 1.1 CFU/mL).
Onset of sidewise instability and cell–dendrite transition in directional solidification

Abstract The transition from cellular to dendritic microstructure in directional solidification is investigated in succinonitrile (SCN)–camphor alloys. This transition is found not to be sharp, but occurs locally over a range of velocities or thermal gradients, and the diffuseness of the transition is related to the existence of a range of primary spacing. Within the transition zone, critical cell spacing λ cd is present where a cell just develops sidewise perturbations. An expression for the critical spacing for the onset of sidewise perturbation is obtained, and it is used to establish the conditions for the start and end of the transition. The results of the present study are then synthesized with those in the SCN–acetone system to incorporate the effect of system parameters on the onset of sidewise instability.
A Simple, Similarity-based Model for Selectional Preferences

We propose a new, simple model for the automatic induction of selectional preferences, using corpus-based semantic similarity metrics. Focusing on the task of semantic role labeling, we compute selectional preferences for semantic roles. In evaluations the similarity-based model shows lower error rates than both Resnik’s WordNet-based model and the EM-based clustering model, but has coverage problems.
The power of conventions: A theory of social preferences

Abstract People often act as if they care about others’ welfare as well as their own (i.e. have “social preferences”). One plausible assumption is that people have preferences for social implications of their actions, determined by exogenous “conventions”, in addition to the material consequences of actions. I construct games with conventions using the psychological games framework developed in Geanakoplos et al. [Geanakoplos, J., Pearce, D., Stacchetti, E., 1989. Psychological games and sequential rationality. Games and Economic Behavior 1, 60–79]. With a notion of distributional convention combining efficiency and fairness, I show equilibrium behavior reflects social preferences. The model yields tight and testable predictions consistent with a large body of experimental results, is parsimonious, and is suggestive of further studies, both experimentally and theoretically.
Pattern representations and syntactic classification of radar measurements of commercial aircraft

A syntactic pattern recognition system is evaluated for applications to radar signal identification. Three different level-crossing-based pattern representation algorithms are considered. The utility of the resulting symbolic pattern representations is assessed by evaluating the performance of a maximum-likelihood classifier when the observed symbol strings are used as inputs to the decision algorithm. A syntax analysis algorithm is derived from the likelihood function classifier. Performance results of simulated classification experiments for both maximum-likelihood and language-theoretic classifiers are presented. >
Fine balance in the regulation of DnaB helicase by DnaC protein in replication in Escherichia coli.

The DnaC protein of Escherichia coli is essential for replication in vivo and in vitro. In the initiation of replication of a minichromosome at its origin, DnaC delivers the DnaB helicase from a DnaB.DnaC complex to the future replication fork and then departs. However, if an excess of DnaC was present in subsequent steps, it severely inhibited replication by slowing the DnaB helicase at the replication fork. When DnaB was present at a level equimolar with the excess DnaC, the inhibition was relieved, implying that the ratio of DnaC to DnaB is critical for achieving optimal replication activity and avoiding inhibition by DnaC. In vivo, overproduction of DnaC slowed cell growth. This slowing was alleviated by overproducing DnaB at the same time. E. coli strains with a dnaCts gene defective in chromosomal initiation were complemented by the wild-type gene in trans. On the other hand, strains with an elongation-defective dnaCts gene were not complemented by the wild-type dnaC gene. The dominance of the mutant protein suggests that it remains tightly complexed with DnaB at the replication fork, inhibiting elongation even in the presence of the wild-type DnaC.
Drag force in AdS/CFT

The AdS/CFT correspondence and a classical test string approximation are used to calculate the drag force on an external quark moving in a thermal plasma of N=4 super-Yang-Mills theory. This computation is motivated by the phenomenon of jet-quenching in relativistic heavy ion collisions.
Measurements of Form and Frictional Drags over a Rough Topographic Bank

Pressuredifferencesacrosstopographygenerateaform dragthatopposestheflow in the watercolumn,and viscous and pressureforcesacting on roughnesselements of the topographic surface generatea frictionaldrag on the bottom. Form drag and bottom roughness lengths were estimated over the East Flower Garden Bank (EFGB) in the Gulf of Mexico by combining an array of bottom pressure measurements and profiles of velocity and turbulent kinetic dissipation rates. The EFGB is a coral bank about 6km wide and 10km long located at the shelf edge that rises from 100-m water depth to about 18m below the sea surface. The average frictional drag coefficient over the entire bank was estimated as 0.006 using roughness lengths that ranged from 0.001cm for relatively smooth portions of the bank to 1‐10cm for very rough portions over the corals. The measured form drag over the bank showed multiple time-scale variability. Diurnal tides and lowfrequency motions with periods ranging from 4 to 17 days generated form drags of about 2000Nm 21 with average drag coefficients ranging between 0.03 and 0.22, which are a factor of 5‐35 times larger than the average frictional drag coefficient. Both linear wave and quadratic drag laws have similarities with the observed form drag. The form dragis an important flow retardation mechanismevenin the presence of the large frictional drag associated with coral reefs and requires parameterization.
Efficiency, capacity, compensation, maintenance, plasticity: emerging concepts in cognitive reserve

Cognitive reserve (CR) is a concept meant to account for the frequent discrepancy between an individual's measured level of brain pathology and her expected cognitive performance. It is particularly important within the context of aging and dementia, but has wider applicability to all forms of brain damage. As such, it has intimate links to related compensatory and neuroprotective concepts, as well as to the related notion of brain reserve. In this article, we introduce the concept of cognitive reserve and explicate its potential cognitive and neural implementation. We conclude that cognitive reserve is compatible and complementary with many related concepts, but that each much draw sharper conceptual boundaries in order to truly explain preserved cognitive function in the face of aging or brain damage.
Design of low-voltage CMOS continuous-time filter with on-chip automatic tuning

A technique for designing a low-voltage continuous-time active filter is presented in this paper. In this technique, current sources are added to the inverting or noninverting op-amp terminals such that the op-amp input common-mode voltages can be set close to one of the supply rails to allow low-voltage operation. An automatic frequency and Q tuning technique is proposed for tuning the active filter using programmable capacitor arrays (PCAs). The proposed tuning technique does not require any peak detectors, which are difficult to implement at a low supply voltage. Instead, it uses a few analog comparators, a digital comparator, and a few binary counters to adjust the PCAs. To demonstrate the proposed techniques, a 1-V 1-MHz second-order filter fabricated in a conventional 1.2-/spl mu/m CMOS process is presented. For a 5-kHz input signal, the filter achieves a THD of -60.2 dB for a peak-to-peak output voltage of 600 mV. The frequency tuning range is between 585 kHz and 1.325 MHz. The measured power consumption for the filter alone consumes about 0.52 mW and for the entire system consumes about 1.6 mW for a supply voltage of /spl plusmn/0.5 V.
A High-Frequency Transconductor Using a Robust Nonlinearity Cancellation

This brief deals with the design of a linear operational transconductance amplifier (OTA) intended for high-frequency continuous-time filters. Three source-degenerated differential pairs are used to reduce the third-order distortion components regardless of process parameter tolerances and bias current. Experimental results for an OTA fabricated in the TSMC 0.35-mum CMOS process are presented and compared with recently reported topologies. Draining 2.8 mA from a single supply voltage of 3.3 V, the transconductor achieves IM3<-70 dB for a two-tone input signal of 1.3 Vpp measured at 70 MHz. The input referred noise density is only 7 nV/radicHz, leading to an SNR of 75 dB
Molecular analysis of Drosophila melanogasterAdhnLA405 confirms reliability of DNA-sequencing methodology

An alcohol dehydrogenase (ADH) null mutant of Drosophila melanogaster (AdhnLA405) originally recovered following X-ray irradiation of mature sperm (Aaron, 979) is analyzed by Southern blotting, Western blotting, and DNA sequencing. The genetic, immunologic, and nucleic acid sequence data are consistent with the hypothesis that a cross-over event, independent of X-irradiation, between parental chromosomes is responsible for the ADH null phenotype of AdhnLA405. By DNA-sequence analysis we show that molecular cloning of this locus (i.e., propagation in prokaryotic hosts) apparently does not introduce any spurious changes (substitutions, additions, deletions, or rearrangements) within the DNA.
Management of equine orthopedic pain

Pain management is an extremely vital part of equine orthopedic surgery. Providing optimum analgesia for the patient will decrease recovery time, decrease physiologic stress on the animal, and provide maximum comfort during the post-operative period. The major analgesic drug categories and routes covered are nonsteroidal anti-inflammatory drugs, local anesthetics, intra-articular drugs, and epidurals.
Late Adolescent Girls’ Sexual Experiences and Sexual Satisfaction

This study presented and tested a model of sexual satisfaction for late adolescent girls. In this model, sexual self-concept and approach sexual motives were tested as predictors of adolescent girls’ sexual satisfaction with their most recent experience of sexual intercourse. A total of 116 girls in 12th grade (ages 16-19) completed measures of sexual self-concept and sexual experiences. A smaller number of girls (n = 70) with intercourse experience completed measures of their motives for engaging in sex and their sexual satisfaction with their most recent intercourse experience. Results showed that both sexual self-concept and approach sexual motives were associated with greater sexual experience across a broad range of sexual behaviors. Furthermore, sexual self-concept and approach sex motives predicted higher sexual satisfaction at most recent intercourse. The importance of investigating positive factors in girls’ developing sexuality is discussed.