cssi/SciSciGPT-SciSciNet huggingface dataset:
Dislocation sub-boundary arrays in oriented thin-film bicrystals of gold

Abstract A technique for producing any type of planar dislocation sub-boundary in thin-film bierystal specimens of gold under controlled conditions is described. Single crystal thin films of the desired orientations are first grown epitaxially on appropriate substrates from the vapour phase. Two films, while still on their substrates, are then welded together face-to-face at any desired mis-orientation to produce a thin-film bierystal containing a planar dislocation array at the welded interface. The substrates are then dissolved away to allow examination of the sub-boundary at normal incidence by transmission electron microscopy. The technique is applied to the study of pure twist sub-boundaries on (001) and (111) planes in gold. Features of the structures of these boundaries are described. Further possible applications are discussed.
The Automorphism group of an [18,9,8] quaternary code

Abstract An [18,9,8] extremal self-dual code over GF(4) and related [17,4,12], [17,8,8], [17,9,7], [17,13,4] codes are investigated. Simple coordinates are given for these codes, and their minimal weight codewords and automorphism groups are determined. The groups are all isomorphic to 3 x (PSL2(16).4).
Is there a Future for Cyclo-Oxygenase Inhibitors in Alzheimer’s Disease?

Several epidemiological studies have indicated that the long-term use of NSAIDs, most of which are cyclo-oxygenase (COX) inhibitors, may reduce the risk of Alzheimer’s disease. For this reason, anti-inflammatory COX-inhibiting NSAIDs have received increased attention in experimental and therapeutic trials for Alzheimer’s disease. However, several recent efforts attempting to demonstrate a therapeutic effect of NSAIDs in Alzheimer’s disease have largely failed. Clinicians and scientists currently believe that this lack of success may be attributable to two key problems: (i) clinical trials of NSAIDs have been conducted in patients with late-stage Alzheimer’s disease, wherein advanced neurodegeneration may be refractory to anti-inflammatory drug treatment; and (ii) it is not known which of the large family of NSAIDs (i.e. COX-1, COX-2 or mixed inhibitors) is most efficacious in preventing Alzheimer’s disease. The wide list of putative functions for COX in the brain, and the significant functional heterogeneity of NSAIDs, which appear to influence the β-amyloid (Aβ) neuropathology associated with Alzheimer’s disease via both COX-dependent and COX-independent pathways, complicate the interpretation of the mechanisms through which COX-inhibiting NSAIDs may beneficially influence Alzheimer’s disease. As discussed in this review, for patients at high risk of developing Alzheimer’s disease (e.g. those with mild cognitive impairment), preventative treatment with COX-inhibiting NSAIDs may ultimately represent a viable strategy in the management of clinical Alzheimer’s disease. However, the recent evidence showing an increased risk of major cardiovascular events among patients treated with certain COX-1 and COX-2 inhibitors leaves many questions unanswered. We suggest that further investigation into the physiological role(s) of COXs in normal health and in disease conditions, and the identification of safer and better tolerated COX inhibitors, will provide renewed impetus to the application of anti-inflammatory strategies for the prevention and treatment of Alzheimer’s disease.
Mortality from cancers of major sites in female radium dial workers

The female radium dial workers have now experienced significant mortality from cancers other than the bone sarcomas and head carcinomas long known to be radium induced. The relationships of radium exposure to mortality from cancers of the stomach, pancreas, colon, rectum, liver, lung, breast, cervix, and corpus uteri, and from leukemia were studied in 1,285 pre-1930 dial workers. Mortality was compared with that expected from rates for US white females, with and without adjustment for local area mortality rates, and with mortality in dial workers exposed from 1930 to 1949. For the 693 cases whose body content of radium has been measured since 1955, dose-response relationships of cancer to systemic intake of radium and duration of employment were examined. Liver, pancreatic, cervical, and uterine cancers were clearly unrelated to radium exposure. Other cancers of the digestive tract appeared to be indirectly, if at all, associated with work in radium facilities. Lung cancer requires further investigation; inhalation exposures of the dial workers were reviewed. Analyses of the breast cancer data uncovered several observations inconsistent with the previously suggested causal association with radium exposure. Multiple myeloma was also reviewed. A threefold excess risk of death due to multiple myeloma has occurred, but is more closely correlated with duration of employment (a surrogate for external gamma radiation) than with radium intake.
Methodological problems in conditioning the headturning response of newborn infants.

Abstract Forty newborn infants received tactile stimulation to the cheek, followed by glucose solution which was either contingent (Experimental S s) or noncontingent (Control S s) upon an ipsilateral headturn. Treatment groups were subdivided into No-Drug or Drug groups, on the basis of medication given to mothers in the 4-hr period preceding delivery. Results indicated no main effect of maternalmedication. There was a main effect of Treatment, with Experimental S s responding with more headturning than Control S s. The Experimental S s did not maintain their increased responding throughout trials, but tended to return to the Control group's level of responding toward the end of conditioning. When S s were categorized into subgroups on the basis of state of wakefulness when entering the experimental room, “awake” S s proved to be significantly more responsive than did “asleep” S s. All S s had experienced a wake-up procedure in order to control for arousal state at the beginning of conditioning. However, those S s spontaneously awake showed more headturning throughout the session than did those S s initially rated asleep, but rated awake after the wake-up procedure. In discussing the discrepancies between this study and previous conditioned headturning studies by Siqueland and Lipsitt (1966) , the authors noted that S s in the earlier work had all been spontaneously awake, and that a smaller headturn was reinforced than in the present study.
Preterm labor: One syndrome, many causes

Preterm birth is associated with 5 to 18% of pregnancies and is a leading cause of infant morbidity and mortality. Spontaneous preterm labor, a syndrome caused by multiple pathologic processes, leads to 70% of preterm births. The prevention and the treatment of preterm labor have been long-standing challenges. We summarize the current understanding of the mechanisms of disease implicated in this condition and review advances relevant to intra-amniotic infection, decidual senescence, and breakdown of maternal-fetal tolerance. The success of progestogen treatment to prevent preterm birth in a subset of patients at risk is a cause for optimism. Solving the mystery of preterm labor, which compromises the health of future generations, is a formidable scientific challenge worthy of investment.
Adapted waveform analysis as a tool for modeling, feature extraction, and denoising

We describe the development of adapted waveform analysis (AWA) as a tool for fast processing of the various identification tasks involved in medical diagnostics and automatic target recognition. Such tasks consist of steps: representing the signal as a superposition of component functions, choosing to retain some of the components and discard the others, then reconstructing a new, approximate signal from what was kept. AWA provides tools for each of these steps, accelerating the decomposition and reconstruction computations, providing new functions for analysis and modeling, and extracting new features for recognition and classification. AWA extends Fourier analysis by providing new libraries of standard waveforms with properties akin to windowed sines and cosines, and it extends principal component analysis and eigen-function expansions by adapting the standard functions to individual operators. The cost of representing a function can be measured by how many components must be superposed to obtain a desired degree of approximation, and this cost can be minimized by a fast search through the library of representations. The analysis can be iterated to sift coherent signals from noise. We consider applications to signal and image compression, feature detection, and medical image denoising.
Three dozen papers on online algorithms

This column contains a summary of last year's research on online algorithms presented at the STOC, FOCS, ICALP, ESA, and STACS conferences. Unfortunately, due to space constraints, the report could not be entirely exhaustive, and results from other conferences or journal articles are not covered. We hope that all readers will find in the survey something of interest, to fill those long winter evenings. The papers in the report are organized roughly by applications.
Improving the quality of online journals: Follow-up study of Elsevier's backfiles image rescanning project

A previous study by the author of 35 titles in Elsevier's Earth and Planetary Sciences digital back file package revealed that 73.6% of the 6,038 issues published before digital format was available had at least one figure with unacceptable quality. During 2006–2009 Elsevier conducted a rescanning project to improve the quality of the images in their backfile packages for issues published prior to 1995. The author conducted a follow-up study to determine the effectiveness of Elsevier's rescanning project. Although the project corrected many problems, a noticeable number of line drawings are still unacceptable, as well as images in issues published during the 1995–1998 time period.
Dual-Layer Asymmetric Microporous Silica Membranes

We report a novel sol-gel dip-coating process to form dual-layer microporous silica membranes with improved membrane performance and reproducibility. First, we deposit a surfactant-templated silica (STS) intermediate layer on top of a commercial {gamma}-alumina support both to improve its ''surface finish'' and to prevent a subsequently deposited microporous overlayer from penetrating into the support. Second, membranes are processed under clean room conditions to avoid dust contamination and, third, membranes are vacuum-calcined to promote further pore shrinkage and impart surface hydrophobicity. The resulting asymmetric membrane exhibits a gradual change in pore diameter from 50{angstrom} ({gamma}-alumina support layer) to 10-12{angstrom} (STS intermediate layer), and then to 3-4{angstrom} (30nm thick, ultramicroporous silica top-layer). Compared to a single-layer process using only the microporous overlayer, the dual-layer process improves both flux and selectivity. For the industrially important problem of natural gas purification, the combined CO{sub 2} flux [(3{approx} 0.5) x 10{sup {minus}4} cm{sup 3}(STP)/(s{center_dot}cm{sup 2}{center_dot}cm-Hg)] and CO{sub 2}/CH{sub 4} separation factors [200{approx}600] are superior to all previously reported values for separation of a 50/50 (v/v) CO{sub 2}/CH{sub 4} gas mixture. In addition, the membrane selectively separated hydrogen from a simulated reformate from partial oxidation of methanol as evidenced by a high concentration of hydrogen recovery.
Monitoring land cover change in urban and peri-urban areas using dense time stacks of Landsat satellite data and a data mining approach

Abstract Given the pace and scale of urban expansion in many parts of the globe, urban environments are playing an increasingly important role in daily quality-of-life issues, ecological processes, climate, material flows, and land transformations. Remote sensing has emerged as a powerful tool to monitor rates and patterns of urban expansion, but many early challenges – such as distinguishing new urban land from bare ground – remain unsolved. To deal with the high temporal and spatial variability as well as complex, multi-signature classes within settlements, this paper presents a new approach that exploits multi-seasonal information in dense time stacks of Landsat imagery using a multi-date composite change detection technique. The central premise of the approach is that lands within/near urban areas have distinct temporal trajectories both before and after change occurs, and that these lead to characteristic temporal signatures in several spectral regions. The method relies on a supervised classification that exploits training data of stable/changed areas interpreted from Google Earth images, and a ‘brute force’ approach of providing all available Landsat data as input, including scenes with data gaps due to the Scan Line Corrector (SLC) problem. Three classification algorithms (maximum likelihood, boosted decision trees, and support vector machines) were tested for their ability to monitor expansion across five time periods (1988–1995, 1996–2000, 2001–2003, 2004–2006, 2007–2009) in three study areas that differ in size, eco-climatic conditions, and rates/patterns of development. Both the decision trees and support vector machines outperformed the maximum likelihood classifier (overall accuracy of 90–93%, compared to 65%), but the decision trees were superior at handling missing data. Adding transformed features such as band metrics to the Landsat data stack increased accuracy 1–4%, while experiments with a reduced number of features (designed to mimic noisy or missing data) led to a drop in accuracy of 1–9%. The methodology also proved particularly effective for monitoring peri-urbanization outside the urban core, capturing > 98% of village settlements.
An architecture for a multimedia teleconferencing system

We present an object-oriented architecture for a computer-based, real-time, multimedia conferencing system. This architecture divides the system into five functional areas: a multimedia shared workspace, a user interface, conference management, communications, and an information base. The structure and operation of the first four areas are modeled with object-based concepts that address design requirements identified during the development of a proof-of-concept prototype, that preceded the architecture specification.The shared workspace, the most important component, is thoroughly discussed; the other components support its realization. The modeling of workspace entities emphasizes their aggregation into composed entities and the homogeneous handling of several data media. The user interface manages uniformly the man-machine interaction for both local and remote user actions. Conference management deals with session establishment, participation, and control of multiple media floors. The communication functions replicate user actions over workspace objects in all hosts participating in a conference, matching traffic types with transmission services in the process.
Visual imagery versus visual experience of familiar individuals

Subjects rated the physical similarity of familiar individuals from photographs and mental images. Multidimensional scaling and hierarchical clustering techniques revealed little difference between photographs and mental images in the subjects’ similarity ratings. This result implies that people’s preexisting imaginal representations derived from direct experience are functionally equivalent to their visual percepts of human beings.
Kinetic Mechanism and Intrinsic Isotope Effects for the Peptidylglycine α-Amidating Enzyme Reaction†

The bifunctional peptidylglycine α-amidating enzyme catalyzes the C-terminal amidation of glycine-extended peptides. The first enzyme activity, peptidylglycine α-hydroxylating monooxygenase, catalyzes the oxygen-, ascorbate-, and copper-dependent formation of α-hydroxyglycine derivatives. These are substrates for the second enzyme activity, peptidylamidoglycolate lyase, which catalyzes their breakdown to the corresponding C-terminal amidated peptide and glyoxylate as final products. Kinetic and isotope effect studies were carried out with N-benzoylglycine as a substrate at pH 6.0 using monofunctional and bifunctional monooxygenase activities. Kinetic data indicate an equilibrium ordered mechanism, with hippuric acid binding first followed by oxygen. A potentially important difference between the two monooxygenase activities is that product release occurs more slowly from the bifunctional enzyme, indicating an influence of the lyase domain on release of α-hydroxyglycine product to solution. Intrinsic isoto...
Abstract 4611: Multimodal activation of apoptosis by a hydrocarbon-stapled PUMA BH3 helix.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC The BH3 domain of BCL-2 family proteins is a critical interaction motif that mediates the crosstalk among anti- and pro-death members. We have applied hydrocarbon stapling to restore alpha-helical structure to synthetic BH3 domain peptides, recapitulating the architecture observed in the native context and/or when bound to their physiologic targets. By generating Stabilized Alpha-Helices of BCL-2 domains (SAHBs) modeled after the BID and BIM BH3 domains, we previously detected direct, quantifiable, and functional binding interactions with both anti- and pro-apoptotic BCL-2 family proteins. Like BIM BH3, PUMA BH3 is well known to broadly engage the variety of anti-apoptotic targets. However, the ability of PUMA BH3 to directly bind and activate BAX remains unresolved. Here, we report the synthesis of PUMA SAHB, a structurally-stabilized PUMA BH3 helix that, in addition to targeting the complete spectrum of anti-apoptotic proteins, directly binds to BAX. Structural analysis revealed that PUMA SAHB engages the α1/α6 trigger site of BAX in a manner analogous to the BIM BH3 helix. PUMA SAHB binding triggers functional BAX activation as reflected by dose-responsive and sequence-dependent BAX-mediated liposomal and mitochondrial release. Importantly, biotin-PUMA SAHB and Flag-PUMA protein pull-downs from cellular lysates confirm binding to the corresponding native multidomain anti- and pro-apoptotic targets. As PUMA has been implicated in driving apoptosis of a variety of neuronal cell types, we explored the therapeutic potential of PUMA SAHB activity in the context of neuroblastoma. Treatment of a variety of neuroblastoma cell lines, including SH SY5Y, Kelly and IMR5, induced dose-responsive caspase 3/7 activation and cell death. To confirm the on-target effects of PUMA SAHB, genetically modified cells lacking BAX and BAX were similarly treated, but no caspase 3/7 activation or viability effects were observed. Thus, we find that a stapled PUMA BH3 helix is a dual anti-apoptotic inhibitor and pro-apoptotic direct activator that may serve as an effective pharmacologic trigger of apoptosis in cancers of neural origin. This work was supported by NIH grant R01 CA050239 to L.D.W. and an NSF Graduate Research Fellowship to A.L.E. Citation Format: Amanda L. Edwards, Evripidis Gavathiotis, James L. LaBelle, Craig R. Braun, Kwadwo Opoku-Nsiah, Gregory H. Bird, Loren D. Walensky. Multimodal activation of apoptosis by a hydrocarbon-stapled PUMA BH3 helix. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4611. doi:10.1158/1538-7445.AM2013-4611
A hybrid channel allocation algorithm with priority to handoff calls in mobile cellular networks

This paper proposes and investigates a novel analytical model of a hybrid channel allocation algorithm within wireless cellular networks. Each cell of the network consists of a predesigned fixed number of channels and the network may approve the request for extra channels for both new and handoff calls if all predesigned channels are occupied. This approval depends on the types of new and handoff calls, as well as the number of approved additional channels in the cell. If a request is denied for the arriving new call, this call will be blocked and cleared from the system. However, if a request is denied for an arriving handoff call, this call will not be blocked immediately but rather put on hold in a buffer with finite space. The implication behind this is to give priority to handoff calls. For this proposed hybrid channel allocation scheme, we first obtain the stationary distribution of each cell when there are i calls connecting to the system and j calls holding on in the buffer. We then derive new and handoff call blocking probabilities, the average number of borrowed channels, and the average delay period of handoff calls. The numerical results show that the proposed hybrid algorithm is more efficient than other approaches, specifically, in comparison with methods without a borrowing capability for new calls and those without a reserved buffer priority for handoff calls. The idea and results presented in this paper are expected to provide guidelines for field data processing within current wireless and mobile network design and performance evaluation.
Stimulation of platelet serotonin transport by substituted 1,4-naphthoquinone-induced oxidant stress

Abstract The effect of oxidant stress produced by redox cycling of substituted 1,4-naphthoquinones on the activity of platelet (Na + -K + )ATPase and the active transport of serotonin (5-HT) was studied. 2-Methy1-1,4-naphthoquinone (menadione) produced a concentration-dependent (0–100 μM) and time-dependent (2–20 min) stimulation of platelet 5-HT transport. Exogenous Superoxide dismutase (250 units) and/or catalase (500 units) failed to block the stimulation. Fluoxetine, an inhibitor of the platelet 5-HT transporter, blocked menadione-induced stimulation of 5-HT uptake as did ouabain, an inhibitor of platelet (Na + -K + )ATPase. The structure-activity relationship of select 1,4-naphthoquinones suggested that stimulation was due to redox cycling and not arylation. The kinetics of 5-HT transport revealed that menadione markedly increased the maximal rate of 5-HT transport ( V max control = 20.6 ± 2.0 pmol/10 8 platelets/4 min vs V max menadione = 46.4 ± 3.9 pmol/10 8 platelets/4 min) but did not significantly alter the K m values. The activity of (Na + K + )ATPase was determined by measuring the uptake of 86 Rb + into intact platelets. Menadione produced a concentration-dependent and time-dependent stimulation of platelet 86 Rb + uptake. These changes in platelet (Na + -K + )ATPase activity paralleled the changes observed in 5-HT transport and were inhibited in a concentration-dependent manner by ouabain. The data have shown that the redox cycling of 1,4-naphthoquinones caused an increase in (Na + -K + )ATPase activity that resulted in the stimulation of the rate of platelet 5-HT transport.
Characterization of a nucleolar residue fraction that specifically transcribes preribosomal RNA

Abstract Treatment of isolated nucleoli with Sarkosyl (2%) dissociated 99.5% of the proteins. The residual DNA-protein complex contained the endogenous transcriptional activity which had a high fidelity of RNA synthesis. Electron microscopic analysis of this residue fraction showed the presence of 150–200 A diameter protein globules present along the length of some of the DNA fibers. SDS-polyacrylamide gel electrophoretic analysis of the proteins of the complex indicated that the subunits of purified RNA polymerase I were only a minor component of this complex. Associated with the complex were the U3 and 5S RNA.
The Extracellular Domain of Receptor Activity-modifying Protein 1 Is Sufficient for Calcitonin Receptor-like Receptor Function

A functional calcitonin gene-related peptide (CGRP) receptor requires dimerization of calcitonin receptor-like receptor (CRLR) with receptor activity-modifying protein 1 (RAMP 1). To determine the function of the three domains (extracellular, ECD; transmembrane, TM; and tail domains) of human RAMP 1, three mutants were constructed: RAMP 1 without the cytoplasmic tail, a chimera consisting of the ECD of RAMP 1 and the TM and tail of the platelet-derived growth factor receptor, and the ECD of RAMP 1 alone. These RAMP 1 mutants were examined for their ability to associate with CRLR to effect CGRP-stimulated cAMP accumulation, CGRP binding, CRLR trafficking, and cell surface expression. All RAMP 1 mutants were able to associate with CRLR with full efficacy for CGRP-stimulated cAMP accumulation. However, the RAMP 1/platelet-derived growth factor receptor chimera demonstrated a 10-fold decrease in potency for CGRP signaling and binding, and the RAMP 1-ECD mutant had a 4000-fold decrease in potency. In conclusion, the ECD of RAMP 1 is sufficient for normal CRLR association and efficacy. The presence of a TM domain and the specific sequence of the RAMP 1 TM domain contribute to CGRP affinity and potency. The C-terminal tail of RAMP 1 is unnecessary for CRLR function.
Central neck dissection for infected or recurrent thyroglossal duct cysts

Recurrence of clinically apparent thyroglossal duct cysts removed using the classic Sistrunk procedure exceeds 4%, even in skilled hands. When a thyroglossal duct cyst is infected at the time of surgery, the Sistrunk operation is unsuccessful in 40% of children. En bloc central neck dissection can reduce the risk of initial failure in difficult cases and adequately treat recurrent lesions.
Rapid development of translation tools: application to Persian and Turkish

The Computing Research laboratory (CRL) is developing a machine translation toolkit that allows rapid deployment of translation capabilities. This toolkit has been used to develop several machine translation systems, including a Persian-English and a Turkish-English system, which will be demonstrated. We present the architecture of these system as well as the development methodology.
Bio-Volatilization of Polonium: Results from Laboratory Analyses

Polonium, like other elements in the Group VI Oxygen series (S, Se, Te), has the potential to form volatile alkyl derivatives. This may be evident in its pervasive radioactive excesses in the atmosphere and coastal waters, and its deficiency in surface open ocean waters. We present evidence for the formation of volatile polonium species. The first evidence comes from duplicating experiments that proved the existence of volatile tellurium, its Group VI congener. Cultures of bread mold at room temperature spiked with polonium tracers showed a significant and reproducible loss of about 0.5% per day of volatile polonium species. In another set of experiments, between 30–50% loss of210Po was observed from Floridan groundwater when nitrogen was bubbled through it over durations of 5–30 minutes. Polonium volatility is highly relevant for biogeochemical studies because it may provide a natural radiochemical tracer for recycling of similar volatile sulfur and other Group VI metal species between the geosphere, atmosphere, and hydrosphere.
Hydrogen in compound semiconductors

Phenomena associated with hydrogen in compound semiconductors include the formation of complexes with both dopant impurities and deep-level defects, the generation of hydrogen-related deep-level defects, and the migration of isolated hydrogen as a charged species. In addition to reviewing these phenomena, this paper describes the depletion-layer technique for determining thermal dissociation energies of hydrogen-impurity complexes and presents an updated tabulation of the parameters that have thus far been obtained from experimental studies to quantitatively describe hydrogen-dopant complexes and hydrogen migration in GaAs.
From vision to reality: The emerging information professional

What will it mean to be an information professional in coming decades? How can we shape the public perception of our slice of the economy? How will job opportunities change? This panel session shares the insights from two recent conferences that brought together thought leaders from around the country to envision the future of information professionals. Panelists who are on the front lines of recruitment and who hire information professionals in different environments – biomedical, industry, and government – will then share their perspectives about information professionals. Following initial presentations, the attendees will be encouraged to pose questions to the panelists in an interactive discussion.
Growth and sugar uptake of excised root and callus of tomato

Abstract Excised root and callus of tomato (Lycopersicon esculentum cv. Rutgers) differed in their requirements for carbon. While roots strongly preferred sucrose over glucose and fructose, callus grew well in sucrose and glucose and only slightly less well in fructose. Roots cultured in sucrose were found to have higher levels of sucrose and reducing sugars than those cultured in glucose and fructose. In contrast, the levels of sucrose and reducing sugars of callus cultures maintained in sucrose, glucose and fructose did not differ as much. Glucose and fructose were taken up at lower rates than sucrose by callus and at much lower rates by excised tomato roots. It appears that inability of excised tomato roots to take up glucose and fructose efficiently was the cause of the failure of these two sugars to support growth of excised tomato roots.
Texas Principals--Implications for Perceived Roles.

How the role of principal is viewed by teachers and principals was the subject of the study on which the following article is based. The study was conducted in Texas, but the findings should have meaning for readers everywhere.
Conformational sampling with Poisson–Boltzmann forces and a stochastic dynamics/Monte Carlo method: Application to alanine dipeptide

We apply a combination of stochastic dynamics and Monte Carlo methods (MC/SD) to alanine dipeptide, with solvation forces derived from a Poisson–Boltzmann model supplemented with apolar terms. Our purpose is to study the effects of the model parameters, such as the friction constant and the size of the electrostatic finite difference grid, on the rate of conformational sampling and on the accuracy of the resulting free energy map. For dialanine, a converged Ramachandran map is produced in significantly less time than what is required by stochastic dynamics or Monte Carlo alone. MC/SD is also shown to be faster, per timestep, than explicit methods. © 1997 John Wiley & Sons, Inc. J Comput Chem18: 1750–1759, 1997
Stellar scintillation and the atmosphere’s vertical turbulence profile

The relationship between stellar scintillation in the strong-focusing regime and the atmosphere’s vertical turbulence profile is investigated with numerical simulation. For two distinct atmospheric profiles, the irradiance variance at a point on a telescope aperture is evaluated as a function of the weighted path-integrated turbulence (i.e., Rytov variance). Additionally, we compute the aperture-averaged irradiance variance and the log-amplitude correlation across the aperture as functions of the Rytov variance. For one atmospheric profile, scintillation is dominated by turbulence in the tropopause; for the other, scintillation arises from turbulence in both the tropopause and the lower troposphere. The numerical results indicate that (1) stellar scintillation depends on the actual profile of atmospheric turbulence and not just on its weighted integral and (2) in the strong-focusing regime the irradiance variance is determined primarily by an optical wave’s coherence length as it passes through the tropopause.
THE MFAMOSING LIMESTONE IN SE NIGERIA: OUTCROP-SUBSURFACE CORRELATION AND RESERVOIR DEVELOPMENT

Key sequence-stratigraphic markers define intervals recognised in outcrops and wells in the Aptian-Albian Mfamosing Limestone Formation in SE Nigeria. These markers aid in outcrop-to-subsurface correlation. The influx of siliciclastics and sea-level fluctuations controlled carbonate production. Peritidal, lagoonal and reefal carbonates rim the igneous Oban Massif and reflect an initial relative sea-level highstand. Subsequent sea level fall was accompanied by the progradation of carbonates away from the exposed, siliciclastic-shedding hinterland, and maximal carbonate production took place during a sea-level lowstand, when an open-marine carbonate shelf and a mixed carbonate siliciclastic shoal co-existed side by side. In the Ituk area, wave action abraded the sea floor which was occasionally exposed, and hardgrounds and leached horizons were formed. Bed- and matrix-selective dorag dolomitisation improved the reservoir potential of the carbonates in certain intervals.
Specification of production functions for analyzing technical change and factor inputs in agricultural development

Abstract This paper focuses on some vital issues involed in specifying the number of variables to be included in agriculture's production function and on the functional form that the agricultural production function should assume in the context of a computable general equilibrium model. When land and intermediate inputs (seeds and fertilizers) as well as capital and labor are included, modeling the agricultural sector can best be done in a more disaggregated format than simple Cobb-Douglas or CES specifications. After examining the transcendental logarithmic production function, the paper proposes to adopt ‘nested’ CES specifications on the basis of empirically observed elasticities of substitution.
Structural conservation of distinctive N-terminal acetylation-dependent interactions across a family of mammalian NEDD8 ligation enzymes

Little is known about molecular recognition of acetylated N termini, despite prevalence of this modification among eukaryotic cytosolic proteins. We report that the family of human DCN-like (DCNL) co-E3s, which promote ligation of the ubiquitin-like protein NEDD8 to cullin targets, recognizes acetylated N termini of the E2 enzymes UBC12 and UBE2F. Systematic biochemical and biophysical analyses reveal 40- and 10-fold variations in affinities among different DCNL-cullin and DCNL-E2 complexes, contributing to varying efficiencies of different NEDD8 ligation cascades. Structures of DCNL2 and DCNL3 complexes with N-terminally acetylated peptides from UBC12 and UBE2F illuminate a common mechanism by which DCNL proteins recognize N-terminally acetylated E2s and how selectivity for interactions dependent on N-acetyl-methionine are established through side chains recognizing distal residues. Distinct preferences of UBC12 and UBE2F peptides for inhibiting different DCNLs, including the oncogenic DCNL1 protein, suggest it may be possible to develop small molecules blocking specific N-acetyl-methionine-dependent protein interactions.
Changes in factors influencing consumer debt among Scottish families, 1984—1987

The major objective of this study was to determine socio-economic and debt management factors causing debt problems among Scottish families. Data for this study were collected from the records of the debt counselling segment of the Citizens Advice Bureau in Glasgow, Scotland, during 1984–87. The final sample consisted of 404 cases selected at random. Variables selected for the study included the following socio-economic characteristics: sex, household size, marital status, employment status, sources of income, and total income. Debt variables included in the study were total debt, sources of debt, amount of debt from each source, and total monthly debt payment. Total debt owed by debtors increased by 283% over the 4 year period from 295,113 in 1984 to 836,409 in 1986. The majority of the households had debt to income ratio of 0.50 and on the average owed on eight different types of loans. The largest proportion of debtors (87%) borrowed from finance companies and the largest sums of total debt were also owed to finance companies (52%). Finance companies consistently held this position over the 4 year period. The analysis of variance (ANOVA) results indicate that employment status, number of sources of borrowing, marital status and sex significantly explained the variation in total debt burden. The number of sources is an important factor in debt management. As the numbers of sources of borrowing increases, not only the management of transactions gets complicated and one can easily lose sight of total debt burden, but it also indicates that people start borrowing from high cost sources of borrowing, such as store credit and finance companies. Educators need to emphasize the importance of the variation in cost of borrowing related to various sources in their materials, and these educational efforts should be targeted to females, singles and those who are recently separated and divorced.
Velocity and Timing of Multiple Spherically Converging Shock Waves in Liquid Deuterium

The fuel entropy and required drive energy for an inertial confinement fusion implosion are set by a sequence of shocks that must be precisely timed to achieve ignition. This Letter reports measurements of multiple spherical shock waves in liquid deuterium that facilitate timing inertial confinement fusion shocks to the required precision. These experiments produced the highest shock velocity observed in liquid deuterium (U(s) = 135 km/s at ∼2500 GPa) and also the first observation of convergence effects on the shock velocity. Simulations model the shock-timing results well when a nonlocal transport model is used in the coronal plasma.
Molecular characterization of the borna disease agent

Abstract Borna disease (BD) is a neurologic syndrome characterized by profound disturbances in behavior and the accumulation of specific antigens in limbic system neurons. The potency of brain homogenates from animals with BD to cause disease in normal animals is reduced by exposure to detergents. We have recently described isolation and characterization of clones derived from the BD agent. Here we present evidence that suggests that the BD agent is a negativesense, single-strand RNA virus. The 8.5-kb genome of this virus appears to be associated with nuclei and encodes two major RNA transcripts of 2.1 and 0.8 kb.
A Silver-Coated Antimicrobial Barrier Dressing Used Postoperatively on Meshed Autografts: A Dressing Comparison Study

In an effort to optimize the management of freshly grafted burn wounds, a silver-coated, low-adherence dressing, Acticoat (Smith & Nephew Inc., Largo, FL), was compared with 5% sulfamylon-soaked Exu-Dry burn wound dressings. Twenty subjects admitted to the Loyola University Medical Center were randomized to either Acticoat dressings or 5% sulfamylon-soaked burn wound dressings. Dressings were applied immediately after grafting in the operating room. Acticoat dressings were left in place for 3 days and then changed every 3 days thereafter. Sulfamylon-soaked dressings were changed at 48 hours and then every day. Subjects continued to have dressing changes on a twice-daily basis to wounds that were not grafted managed. Subjects were assessed for graft take, time to wound healing, and the number of dressings required until healing. Hospital charges and labor costs were retrospectively tabulated, yielding an expense estimate for each group. There were no significant differences between the two groups with respect to age, %TBSA, %TBSA of the grafted test sites, graft take, time to graft healing, or infectious complications. The median number of dressing changes to the test site was significantly less in the Acticoat group (P < .05). The average expense per dressing change was not significantly different between the two groups; however, the average total expense per patient was significantly lower for the Acticoat group because of the reduced number of dressing changes. Acticoat and 5% sulfamylon-soaked burn wound dressings were equivalent with respect to wound healing and infectious complications. The use of Acticoat was found to be a safe alternative to the use of 5% sulfamylon as a postsurgical dressing in this group of subjects. Because of the reduced number of dressing changes, the use of Acticoat was a less expensive alternative to 5% sulfamylon dressing changes in this study.
PC anxiety: reliability and validity of a brief scale.

A brief six-item scale to measure confidence in the use of personal computers showed Cronbach α of .76 for internal reliability and construct validity (rpbs of −.16, −.18, −.22 for items of behavioral use).
Competitive physisorption: The interaction of CO and N2 with silica surfaces as studied by ir spectroscopy

Abstract The physical adsorption of N2 on silica surfaces containing isolated hyroxyl groups at 87 K. results in the formation of a hydrogen-bonded complex OH ⋯ N2 which exhibits νN2 = 2330 cm−1 (very weak in intensity), and νOH = 3710 cm−1. This is accompanied by the disappearance of the band due to the isolated OH surface groups at 3743 cm−1. The addition of N2(g) to a system containing the analogous OH ⋯ CO complex causes a reversible conversion to the OH ⋯ N2 surface complex and a displacement of the CO into the gas phase. Both N2 and CO surface complexes are thought to be terminally bound to hydroxyl groups.
Cellulose Nanocrystal Reinforced Alginate Fibers—Biomimicry Meets Polymer Processing

This research takes a biomimetic approach to the design of polymer nanocomposites and demonstrates structure-property relationships that are controllable via processing conditions. Cellulose nanocrystals (CNCs) measuring 130 nm (length) × 20.4 nm (width) × 6.8 nm (height) were isolated from cotton by sulfuric acid hydrolysis and were incorporated in an alginate fiber wet spinning dope solution. Incorporating CNCs within the alginate fiber enables a nearly two-fold increase in the apparent jet stretch (JA ), ratio of the linear draw speed to extrusion velocity. Fiber spinning at a constant JA resulted in an unexpected decrease in fiber modulus and increase in toughness. Alternatively, fiber spinning at the maximum JA resulted in modulus increases that are predicted by the Halpin-Tsai model and the Hui-Shia model. Wide-angle X-ray diffraction (WAXD) was used to elucidate the structure and orientation of cellulose nanocrystals (CNC) within the alginate nanocomposite fibers and provide correlations with mecha...
The Economic Importance of Human Capital in Modernization.

The full effects of human capital are difficult to observe. In addition to the internal effects which enhance the productivity of the individual in whom the investment has been made, there exist external effects—in particular the creation of new knowledge—which may have a large impact on economic growth. Since human capital invents new forms of physical capital, the former is the key to economic progress. Unlike physical capital, however, property rights in human capital—patents, copyrights, workplace safety rights—have often not been strong enough to encourage the most enterprising use of human capital resources.
An asymmetric outgassing model for cometary nongravitational accelerations

The standard nongravitation force model has been modified by allowing the water-vaproization curve to peak a certain number of days (DT) either before or after perihelion, and the modification is shown to often improve the data fit. The best fit to the astrometric data is generally achieved for a value of DT corresponding to the offset in the comet's visual light curve. The asymmetric model, which more accurately mimics the comet's outgassing history, suggests only weakly that the rotation direction of Comet Halley is direct, and it does not provide evidence that the rotation axis of Comet Kopff passed through its orbit plane in the early twentieth century. Approximate lag angles of 4 deg for Comet Halley and 10 deg for Comet d'Arrest are found using the asymmetric model, and it is noted that these values are lower than those obtained with the standard model.
Formal verification of content addressable memories using symbolic trajectory evaluation

In this paper we report on new techniques for verifying contentaddressable memories (CAMs), and demonstrate that these techniqueswork well for large industrial designs. It was shown in [Formal verification of PowerPC(TM) arrays using symbolic trajectory evaluation], that theformal verification technique of symbolic trajectory evaluation (STE)could be used successfully on memory arrays. We have extended thatwork to verify what are perhaps the most combinatorially difficultclass of memory arrays, CAMs. We use new Boolean encodings toverify CAMs, and show that these techniques scale well, in that spacerequirements increase linearly, or sub-linearly, with the various CAMsize parameters.In this paper, we describe the verification of two CAMs froma recentPowerPC microprocessor design, a Block Address Translation unit(BAT), and a Branch Target Address Cache unit (BTAC). The BATis a complex CAM, with variable length bit masks. The BTAC is a64-entry, 64-bits per entry, fully associative CAM and is part of thespeculative instruction fetch mechanism of the microprocessor. Webelieve that ours is the first work on formally verifying CAMs, and webelieve our techniques make it feasible to efficiently verify the varietyof CAMs found on modern processors.
Global existence of small solutions to nonlinear evolution equations

Abstract We study the global existence and asymptotic behaviour of “small” solutions of a large class of nonlinear partial differential equations. If the nonlinear terms are of high degree the solutions will be asymptotic to solutions of the linear equation.
On the energy-throughput tradeoffs for relay networks with transmit power control

In this paper we study the bandwidth efficiency (throughput) and energy efficiency of relay networks considering both the physical layer and the medium access control (MAC) layer. Due to the wireless signal power attenuation with transmission distance, adopting a relay for packet transmissions leads to more energy efficient wireless networking at the expense of requiring multi-hop transmissions. To understand benefits of using a relay, the energy-throughput tradeoff needs to be analyzed. In a decentralized wireless network, not only the physical layer but also the MAC layer should be considered because the physical layer affects the MAC layer and the MAC layer overhead is not negligible. However, the energy-throughput tradeoffs for relay networks considering both the physical layer and the MAC layer has not been studied yet. We analyze the energy consumption and the throughput of relay networks with transmit power control. We determine the conditions in which wireless communication using a relay has better energy efficiency or bandwidth efficiency than direct transmission.
Calibration of the Ring Model for the NSLS Rings

The mathematical model of an accelerator can be used to control its operation and also to simulate its behavior. Part of the model is the conversion between the computer controlled digital setpoints of the magnets and the actual field acting on the average particle in the magnet. We are using tune, dispersion and chronaticity measurements to calculate this conversion, thus calibrating the model rather than the magnets themselves. This is one way to include effects, not taken directly into account in the model. The model has to be calibrated at different beam momenta, and possibly at different beam intensities.