cssi/SciSciGPT-SciSciNet huggingface dataset:
Ab initio study of ascorbic acid conformations

The STO-3G optimized structures of nine different staggered conformers of ascorbic acid are presented. The largest energy difference between the nine local minima is 5.1 kcal/mol. Comparison of the relative energies of the fully optimized structures of ascorbic acid conformers with those of nonoptimized conformers shows that full optimization is essential to obtain meaningful results. However, optimization of the ring structure is almost independent of optimization of the side-chain structure. One of the STO-3G optimized gas phase conformers is very close to the X-ray structure of the crystal.
National and supranational Spanish: Complexities of production and migration in literary translation

This study broadly considers textual and extra-textual factors involved in producing and disseminating Spanish translations, dimensions that may be linguistic, socio-linguistic, cognitive, economic, cultural, or legal. Sociolect and regionalect are considered in the translation traffic into Spanish, particularly in their relations to aesthetic verisimilitude or market acceptability. The phenomenon of what has been called textual mobility is traced. According to De Clercq et al. (2006), textual mobility may include translation policy, translator-publisher negotiations, printing industry conditions, copyright considerations, and other power matrices, including censorship and patronage. Censorship’s historical effects on translation policy are borne out in light of translational contraband and distribution. Variants of Spanish are shown to be involved in dynamics of writing from the margins, perceptions of language correctness, including the hybridity and its implications for identity, and the attendant issu...
Predicting Regional-Scale Soil Variability using a Single Calibrated Apparent Soil Electrical Conductivity Model

Multi-field/multi-season approaches used to calibrate apparent soil electrical conductivity (EC a ) models for predicting soil spatial variability across large landscapes are time-consuming. In this study an alternative calibration approach was evaluated. The study was conducted on an agricultural watershed in Texas with the objectives of (i) assessing the contribution of different soil properties to EC a variability; and (ii) evaluating the feasibility of using a single calibration approach to predict soil variability across different fields. Of the soil properties measured, clay content contributed the greatest to EC a variability. The single calibration approach was used to calibrate an EC a -clay model using data from a designated calibration area (CA). When the calibrated model was used to predict clay content in four validation fields, prediction accuracies were between 2 and 4% clay. Accuracies were comparable with other methods indicating that the single-calibration approach was a suitable alternative to multi-field/multi-season calibration approaches.
Chronically administered morphine, circadian cyclicity, and intake of an alcoholic beverage

Subsequent to 22 hr of deprivation of water, 40 male rats were given daily access to water and a sweetened ethanol solution for 2 hr each day for 24 days. Twenty of the rats had this opportunity to take fluids during the light-phase of the circadian cycle while the other twenty were given it during the dark. Prior to the 24 days, some rats (half of each group) were implanted subcutaneously with osmotic pumps giving them constant infusions of morphine (0.6 mg/kg/hr). Across daily sessions, all rats gradually increased their intakes of ethanol with the greatest increases among those having morphine and taking fluids during the light-phase. The rats which drank during the dark gained more weight than the others and the most marked gains in weight were by those receiving no morphine. The data support the conclusion that some general disruption resulting from the schedule of presentation of fluids during the day qualifies as a setting condition for heightened intake of ethanol.
Variational study of ordinary and superconducting cosmic strings

A variational approach is used to study Abelian vortices, both the ordinary and bosonic superconducting variety. Accurate results are presented for the energy per length. For superconducting strings the parameter space of solutions is mapped out, the critical current is quantified, the quench transition is studied, and the possibility of static solutions is investigated where electromagnetic stresses balance the string tension. 13 refs., 2 figs.
A Discrete Model for the Bi-Carleson Operator

We prove Lp estimates for the Walsh model of the maximal bi-Carleson operator defined below. The corresponding estimates for the Fourier model will be obtained in the sequel [MTT4] of this paper.
The regulation and role of neuronal gap junctions during neuronal injury

In the mammalian CNS, excessive release of glutamate and overactivation of glutamate receptors are responsible for the secondary (delayed) neuronal death following neuronal injury, including ischemia, traumatic brain injury (TBI) and epilepsy. The coupling of neurons by gap junctions (electrical synapses) increases during neuronal injury. In a recent study with the use of in vivo and in vitro models of cortical ischemia in mice, we have demonstrated that the ischemic increase in neuronal gap junction coupling is regulated by glutamate via group II metabotropic glutamate receptors (mGluR). Specifically, we found that activation of group II mGluRs increases background levels of neuronal gap junction coupling and expression of connexin 36 (Cx36; neuronal gap junction protein), whereas inactivation of group II mGluRs prevents the ischemia-mediated increases in the coupling and Cx36 expression. Using the analysis of neuronal death, we also established that inactivation of group II mGluRs or genetic elimination of Cx36 both dramatically reduce ischemic neuronal death in vitro and in vivo. Similar results were obtained using in vitro models of TBI and epilepsy. Our study demonstrated that mechanisms for the injury-mediated increase in neuronal gap junction coupling are part of the mechanisms for glutamate-dependent neuronal death.
Perturbation of coupling matrices and its effect on the synchronizability in arrays of coupled chaotic systems

Abstract In a recent paper, wavelet analysis is used to perturb the coupling matrix in an array of identical chaotic systems in order to improve its synchronization. When the coupling matrix is symmetric, the synchronization criterion is determined by the second smallest eigenvalue λ 2 of the coupling matrix and the problem is reduced to studying how λ 2 of the coupling matrix changes with perturbation. In the aforementioned paper, a small percentage of the wavelet coefficients are modified. However, this results in a perturbed matrix where every element is modified and nonzero. The purpose of this Letter is to present some results on the change of λ 2 due to perturbation. In particular, we show that as the number of systems n →∞, perturbations which only add local coupling will not change λ 2 . On the other hand, we show that there exists perturbations which modify an arbitrarily small percentage of matrix elements, each of which is changed by an arbitrarily small amount and yet can make λ 2 arbitrarily large. These results give conditions on what the perturbation should be in order to improve the synchronizability in an array of coupled chaotic systems. This analysis allows us to justify and explain some of the synchronization phenomena observed in a recently studied network where random coupling is added to a locally connected array. We propose to classify various classes of coupling matrices such as small world networks and scale free networks according to their synchronizability in the limit. Finally, we briefly discuss the case of time-varying coupling.
Mechanistic model of myocardial energy metabolism under normal and ischemic conditions.

A moderate reduction in coronary blood flow results in decreased myocardial oxygen consumption, accelerated glycolysis, decreased pyruvate oxidation, and lactate accumulation. To quantitatively understand cardiac metabolism during ischemia, we have developed a mechanistic, mathematical model based on biochemical mass balances and reaction kinetics in cardiac cells. By numerical solution of model equations, computer simulations showed the dynamic responses in glucose, fatty acid, glucose-6-phosphate, glycogen, triglyceride, pyruvate, lactate, acetyl-CoA, and free-CoA as well as CO2, O2 phosphocreatine/creatine, nicotinamide adenine dinucleotide (reduced form)/nicotinamide adenine dinucleotide (oxidized form) NADH/NAD+, and adenosine diphosphate/adenosine triphosphate (ADP/ATP). When myocardial ischemia was simulated by a 60% reduction in coronary blood flow, the model generated myocardial concentrations, uptakes, and fluxes that were consistent with experimental data from in vivopig studies. After 60 min of ischemia the concentrations of glycogen, phosphocreatine, and ATP were decreased by 60%, 75%, and 50%, respectively. With the onset of ischemia, myocardial lactate concentration increased and the myocardium switched from net consumer to net producer of lactate. Our model predicted a rapid 13-fold increase in NADH/NAD but only a twofold increase in the ratio of acetyl-CoA to free-CoA. These findings are consistent with the concept that pyruvate oxidation is inhibited during ischemia partially by the rise in NADH/NAD+. © 2002 Biomedical Engineering Society. PAC2002: 8717Aa
Derivative studies in hartree-fock and møller-plesset theories

The complete spin-orbital formulation of the analytical first and second derivatives of the Hartree-Fock (HF) energy as well as the analytical first derivative of the correlated second-order Moller-Plesset perturbation energy (MP2) is presented. Some features of an efficient computational method to calculate these derivatives are described. The methods are applied to calculate the harmonic vibrational frequencies of ethylene, and the results are compared with experiment.
A Multi-Dimensional Analysis of the Concept of Burnout

The use of the term "burnout" is traced in the literature and the lack of consensus on the meaning of the phenomenon under study is identified. A multidimensional perspective is suggested and is utilized as the framework for a study of the staff of a large human service organization. The study collected information on perceptions of organizational dynamics; small group and social supports; job satisfaction; job descriptions and job functions; demographic characteristics; and burnout indicators. The burnout indicators provide the source of data analyzed in this phase of the study. Using factor analytic procedures, the writers identify a six factor solution, suggesting that the phenomenon described as "burnout" may be, in fact, at least six, or more, variations, or combinations of the potential burnout indicators. Implications for intervention are discussed.
Combined Tbet and IL12 Gene Therapy Elicits and Recruits Superior Antitumor Immunity In Vivo

We have recently shown that intratumor (i.t.) injection of syngenic dendritic cells (DC) engineered to express the transcription factor Tbet (TBX21) promotes protective type-1 T cell-mediated immunity via a mechanism that is largely interleukin (IL)-12p70-independent. Since IL-12 is a classical promoter of type-1 immunity, the current study was undertaken to determine whether gene therapy using combined Tbet and IL-12 complementary DNA (cDNA) would yield improved antitumor efficacy based on the complementary/synergistic action of these biologic modifiers. Mice bearing established subcutaneous (s.c.) tumors injected with DC concomitantly expressing ectopic Tbet and IL12 (i.e., DC.Tbet/IL12) displayed superior (i) rates of tumor rejection and extended overall survival, (ii) cross-priming of Tc1 reactive against antigens expressed within the tumor microenvironment, and (iii) infiltration of CD8+ T cells into treated tumors in association with elevated locoregional production of CXCR3 ligand chemokines. In established bilateral tumor models, i.t. delivery of DC.Tbet/IL12 into a single lesion led to slowed growth or regression at both tumor sites. Furthermore, DC.Tbet/IL12 pulsed with tumor antigen-derived peptides and injected as a therapy distal to the tumor site prevented tumor growth and activated robust antigen-specific Tc1 responses. These data support the translation use of combined Tbet and IL-12p70 gene therapy in the cancer setting.
Relationship between perceptions about neighborhood environment and prevalent obesity: data from the dallas heart study

Objectives: Although psychosocial stress can result in adverse health outcomes, little is known about how perceptions of neighborhood conditions, a measure of environment-derived stress, may impact obesity. The association between perceptions of neighborhood environment and obesity (defined as body mass index [BMI] ≥ 30 kg/m2) among 5,907 participants in the Dallas Heart Study, a multi-ethnic, probability-based sample of Dallas County residents was examined. Design and Methods: Participants were asked to respond to 18 questions about perceptions of their neighborhood. Factor analysis was used to identify three factors associated with neighborhood perceptions: neighborhood violence, physical environment, and social cohesion. Logistic regression analyses were performed to determine the relationship between each factor (higher quintile = more unfavorable perceptions) and the odds of obesity. Results: Decreasing age, income, and education associated with unfavorable overall neighborhood perceptions and unfavorable perceptions about specific neighborhood factors (P trend <0.05 for all). Increasing BMI was associated with unfavorable perceptions about physical environment (P trend <0.05) but not violence or social cohesion. After adjustment for race, age, sex, income, education, and length of residence, physical environment perception score in the highest quintile remained associated with a 25% greater odds of obesity (OR 1.25, [95% CI 1.03-1.50]). Predictors of obesity related to environmental perceptions included heavy traffic (OR 1.39, [1.17-1.64]), trash/litter in neighborhood (OR 1.27, [1.01-1.46]), lack of recreational areas (OR 1.21, [1.01-1.46]), and lack of sidewalks (OR 1.25, [95% CI 1.04-1.51]). Conclusions: Thus, unfavorable perceptions of environmental physical conditions are related to increased obesity. Efforts to improve the physical characteristics of neighborhoods, or the perceptions of those characteristics, may assist in the prevention of obesity in this community.
Variation compensation and analysis on diaphragm curvature analysis for emphysema quantification on whole lung CT scans

CT scans allow for the quantitative evaluation of the anatomical bases of emphysema. Recently, a non-density based geometric measurement of lung diagphragm curvature has been proposed as a method for the quantification of emphysema from CT. This work analyzes variability of diaphragm curvature and evaluates the effectiveness of a compensation methodology for the reduction of this variability as compared to emphysema index. Using a dataset of 43 scan-pairs with less than a 100 day time-interval between scans, we find that the diaphragm curvature had a trend towards lower overall variability over emphysema index (95% CI:-9.7 to + 14.7 vs. -15.8 to +12.0), and that the variation of both measures was reduced after compensation. We conclude that the variation of the new measure can be considered comparable to the established measure and the compensation can reduce the apparent variation of quantitative measures successfully.
Using Administrative Data for Longitudinal Substance Abuse Research

The utilization of administrative data in substance abuse research has become more widespread than ever. This selective review synthesizes recent extant research from 31 articles to consider what has been learned from using administrative data to conduct longitudinal substance abuse research in four overlapping areas: (1) service access and utilization, (2) underrepresented populations, (3) treatment outcomes, and (4) cost analysis. Despite several notable limitations, administrative data contribute valuable information, particularly in the investigation of service system interactions and outcomes among substance abusers as they unfold and influence each other over the long term. This critical assessment of the advantages and disadvantages of using existing administrative data within a longitudinal framework should stimulate innovative thinking regarding future applications of administrative data for longitudinal substance abuse research purposes.
Event-triggered output feedback stabilization of networked systems with external disturbance

This paper addresses the problem of output feedback stabilization of continuous-time networked systems that are also perturbed by persistent external disturbances. An augmented state observer is designed in order to estimate both the state of the system and the external disturbance. Conditions for observability of the augmented system are provided based on the given system parameters. Stabilization of the output feedback networked system is achieved by means of event-triggered control strategies which reduce the number of feedback updates. A strictly positive lower-bound on the inter-event times is also provided which avoids Zeno behavior. Finally, this framework is extended to consider the existence of network induced delays. Similarly, conditions for stability and bounds on the inter-event times are presented.
Layout rule trends and effect upon CPU design

The trends in layout rules and the affect these rules have upon design are described. The slow improvement in resolution has created a need for litho-friendly design. The problems caused by LFD and the increase in number and complexity of rules are shown. Issues in implementing LFD are discussed.
Hypersonic boundary-layer transition on ablating and nonablating cones

Ablation effects on transition Reynolds number of hypersonic boundary layer on slender cones
The role of the olfactory system in avoidance learning and activity.

Abstract Male rats with bilateral ablations of the olfactory bulbs were tested on several activity measures and in passive and active avoidance situations. They were difficult to handle and more active in an open field than sham operates, were significantly poorer at passive avoidance acquisition, and significantly better at active avoidance. The results were discussed in terms of possible alterations in limbic function leading to hyperreactivity toward external stimulation.
SU(2) instantons with boundary jumps and spin tunneling in magnetic molecules.

Coherent state path integrals are shown in general to contain instantons with jumps at the boundaries, i.e., boundary points lying outside classical phase space. Inclusion of these instantons is shown to resolve the ``missing quench paradox'' in the magnetic molecule ${\mathrm{Fe}}_{8}$, i.e., the fact that the tunneling between the ground Zeeman states of this molecule is quenched at only four magnetic field values, instead of the ten that would be expected from the topological Berry phase between interfering instantons. An approximate formula is found for the location of the four remaining quenches.
Epilepsy, Schizophrenia, and the Extended Amygdala

Propagation and prolongation of rapid neuronal discharge underlies the epilepsies. However, episodic focal rapid neuronal discharges limited to discrete nuclei and pathways of the amygdala-hippocampal-septal-hypothalamic networks are the language of physiologic message systems for endocrine regulation and reproductive activities vital to the survival of the organism and the species. To prevent prolongation and propagation of physiologic pulsed excitation to areas outside specific networks and resultant epileptic seizures, these discharges must be limited in extent and time by powerful inhibitory processes. The nucleus accumbens, a unit of the extended amygdala, and the monoamines and GABA are components of the inhibitory networks that restrict physiologic rapid discharge in duration and in location. In parallel to the relationship of excessive neuronal excitation to epilepsy, evidence will be presented that excessive inhibition via one or more components of these inhibitory networks or diminished excitation underlies development of some psychoses, including schizophrenia.
Mass profiles of galaxy cluster cores

Abstract We present mass profiles for the cores of a sample of relaxed galaxy clusters. We determine if the core plasma in each cluster contains multiple phases, and derive non-parametric baryon density and temperature profiles. We use these to construct total gravitating mass profiles and calculate their core logarithmic density slopes. We find that the cores are roughly consistent with the predictions of Λ CDM; −1 ≲ d log( ρ )/d log ( r ) ≲ −2.
Spectroscopic characterization and mechanistic investigation of P-methyl transfer by a radical SAM enzyme from the marine bacterium Shewanella denitrificans OS217.

Abstract Natural products containing carbon–phosphorus bonds elicit important bioactivity in many organisms. l -Phosphinothricin contains the only known naturally-occurring carbon–phosphorus–carbon bond linkage. In actinomycetes, the cobalamin-dependent radical S-adenosyl- l -methionine (SAM) methyltransferase PhpK catalyzes the formation of the second C–P bond to generate the complete C–P–C linkage in phosphinothricin. Here we use electron paramagnetic resonance and nuclear magnetic resonance spectroscopies to characterize and demonstrate the activity of a cobalamin-dependent radical SAM methyltransferase denoted SD_1168 from Shewanella denitrificans OS217, a marine bacterium that has not been reported to synthesize phosphinothricin. Recombinant, refolded, and reconstituted SD_1168 binds a four-iron, four-sulfur cluster that interacts with SAM and cobalamin. In the presence of SAM, a reductant, and methylcobalamin, SD_1168 surprisingly catalyzes the P-methylation of N-acetyl-demethylphosphinothricin and demethylphosphinothricin to produce N-acetyl-phosphinothricin and phosphinothricin, respectively. In addition, this enzyme is active in the absence of methylcobalamin if the strong reductant titanium (III) citrate and hydroxocobalamin are provided. When incubated with [methyl-13C] cobalamin and titanium citrate, both [methyl-13C] and unlabeled N-acetylphosphinothricin are produced. Our results suggest that SD_1168 catalyzes P-methylation using radical SAM-dependent chemistry with cobalamin as a coenzyme. In light of recent genomic information, the discovery of this P-methyltransferase suggests that S. denitrificans produces a phosphinate natural product.
The first decade of personal computers

The first decade of personal computers is characterized by three generations of these man-made devices. During the last six years alone, the number of personal computers purchased has increased by two orders of magnitude. This rapid growth has been catalyzed by innovations in computing and communication technology and by the advent of systems with friendlier human-machine interfaces geared towards individual needs. As the microelectronics revolution progresses and better software methodologies evolve, the personal computer will find widespread use in nontraditional application areas involving computing operations on information of many different types. This paper discusses the key features of contemporary personal computers. Four different market niches are delineated and their characteristics analyzed.
Thiol oxidase activity of copper, zinc superoxide dismutase stimulates bicarbonate-dependent peroxidase activity via formation of a carbonate radical

Here, we investigated the effect of bicarbonate anion (HCO3-) on the peroxidase activity stimulated by the thiol oxidase activity of copper, zinc superoxide dismutase (SOD1) using electron spin res...
A prototype for convective margin shifts

[1] Regional precipitation anomalies under El Nino or global warming scenarios manifest considerable spatial variability, especially in the vicinity of tropical deep convective zones. Using a simplified set of equations, we develop an analytic prototype of convective margins for tropical land regions subject to inflow from adjacent ocean regions. The approach yields an expression for the location of the convective margin from which it is straightforward to deduce how climate perturbations impact the margin. We compare the results of the prototype to full model simulations of the equatorial South American precipitation response to El Nino forcing and find general agreement. Analysis of the observations supports the convective inflow margin prototype's applicability to appropriately simple basic state configurations.
HOW DO PATIENTS WITH INTERSTITIAL CYSTITIS PRESENT

Purpose: We determined how interstitial cystitis progresses from initial symptoms to diagnosis.Materials and Methods: We retrospectively analyzed the records of 45 patients to determine the dates of symptom onset and diagnosis, and sequence of urgency/frequency, nocturia and pain. We also documented alternate and previous diagnoses, and previous surgical treatments.Results: Of the patients 89% presented with only 1 symptom. Median time from the initial symptom to all symptoms was 2 years (mean 5.5). The most common previous diagnoses were urinary infection in 19 cases, a gynecologic diagnosis in 14 and urethral diagnoses in 6. A previous urinary infection was documented in only 1 of 19 patients, while 11 had undergone hysterectomy and 5 diagnosed with endometriosis had no pathological documentation available.Conclusions: Early interstitial cystitis presents variably and usually with only a single symptom of urgency/frequency, nocturia or pain. Clinicians may fail to appreciate the symptoms of early inters...
Solution by recursion of the N-body electrostatic schrödinger equation.

Abstract A generalized partial wave expansion of atomic wavefunctions has been shown to allow exact solution of the many-electron Schrodinger equation. This solution is constructed here by an algebraic recursion method, and several analytical properties of such wave-functions are easily obtained. Eigenstates of the atom correspond to such solutions which satisfy certain boundary conditions for infinite extension of the system. A method of locating these states is presented.
Concentration of metallothionein in major organs of rats after administration of various metals

The effect of various metals (Cd, Cr, Fe, Pb, Mn, Hg, Ni, Zn) at maximum tolerated doses on metallothionein (MT) concentrations in major organs (brain, heart, intestine, kidney, liver, lung, pancreas, spleen, stomach, and testes) of rats was measured by the Cd-radioassay technique. Zn produced the most dramatic changes in MT, increasing concentrations 260-, 86-, 44-, and 14-fold over control for pancreas, intestine, liver, and kidney, respectively. Zn increased MT in every organ examined except brain. Cd was also effective in increasing MT levels, elevating concentrations in all organs except brain and testes. Testes was the only organ in which a metal decreased MT levels, where Cd produced a 90% decrease. Cr, Fe, Pb, and Mn increased MT concentrations only in hepatic tissue, while Hg and Ni increased MT in liver, kidney, and pancreas. Results indicate that Zn is the most effective inducer of MT synthesis in several tissues and that liver appears to be the most responsive organ to increased MT synthesis following exposure to a number of metals.
Barrier heights and electric-field-induced barrier shifts in doped tunnel junctions

$\mathrm{A}\mathrm{l}\ensuremath{-}\mathrm{Al}{\mathrm{O}}_{x}\ensuremath{-}M$ tunnel junctions with Pb and Ag electrodes have been doped with a series of aromatic compounds and with C and Si. An electric-field-induced shift in the $I\ensuremath{-}\mathrm{v}\mathrm{s}\ensuremath{-}V$ curves is observed for application of bias voltages above a specific threshold value. This field-induced shift is proportional to the maximum voltage applied and has been analyzed in terms of an effective lowering of the barrier height. The barrier shift is stable indefinitely at 4.2 K but can be completely reversed by a short anneal at 300 K. For the aromatic compounds the magnitude of the barrier shift and the threshold voltage are systematically correlated with the $\ensuremath{\pi}$-delocalization and resonance energy. Molecules having the largest calculated resonance energy and reactivity indices induce the largest electric field effects. The initial effective barrier height of the doped junction is also correlated with the resonance energy of the molecule. Substitution of Ag for Pb as the cover electrode systematically lowers both the effective barrier height and the threshold voltage while enhancing the electric-field-induced barrier shift. Doping $\mathrm{Al}{\mathrm{O}}_{x}$ with Si or C produces a strong reduction in effective barrier height, and large electric-field-induced shifts can be observed for both Pb and Ag electrodes. These large changes in electron affinity at the barrier-electrode interface can be associated with hydrogen bonding which involves the charged OH groups on the $\mathrm{Al}{\mathrm{O}}_{x}$ surface. Analysis of model barriers and the effects on inelastic tunneling spectroscopy are discussed.
Linear Probability Models of Undergraduate Student Attitudes toward Economic Regulation

Abstract This study examined the role of student attributes and activities (at the college undergraduate level) in shaping the student's attitudes toward economic regulation. By employing a linear probability model and information gathered from a student questionnaire, several factors were tested that convey many of the empirical ideas revealed previously by academic economists such as Stigler (1971) and Peltzman (1976). By relying on agent attributes such as those developed in the formative years of college, these models may provide the ability to predict future regulatory decisions or appointments to regulatory posts at organizations such as the EPA or the SEC.
You Say You Want A Revolution: Information Technology and Growth

The information technology (IT) revolution has arrived, but how much will it change the world? It has been established that IT is contributing to labor productivity growth through both increases in the levels of IT capital per worker and total factor productivity (TFP) growth in the production of IT equipment. The main outstanding issue is whether IT is contributing to TFP growth more generally. Using data on IT expenditure and production for a broad sample of countries, we find a positive, large, and significant effect of IT expenditure on the acceleration in TFP in the late 1990s and a smaller -and significant- effect of IT production. We also find evidence that the impact of IT expenditure on TFP growth increases over time, suggesting that spillovers materialize gradually. Our results suggest that the increase in IT expenditure across industrial countries during 1995-2000 will eventually lead to an average increase in TFP growth of about one-third of 1 percent per year.
The association of elevated percent bands on admission with failure and complications of interval appendectomy.

Abstract Background/Purpose: The routine use of interval appendectomy for the treatment of perforated appendicitis, with or without abscess, remains controversial. The purpose of this study is to confirm the efficacy of this approach and to identify factors associated with failures and complications. Methods: All patients (n = 101) with their clinical diagnosis of perforated appendicitis confirmed with imaging were treated prospectively with fluids and intravenous antibiotics (clindamycin, ceftazidime) and were discharged home on oral fluids and analgesics regardless of fever. Intravenous antibiotics were continued at home until the patients were afebrile for 48 hours, and their white blood cell and differential counts were normal. Patients were readmitted at 8 to 12 weeks for an interval appendectomy. Failure to improve by 72 hours of antibiotic therapy mandated an early appendectomy. P values were determined by χ 2 analysis and Student's t test. Results: The 79 patients (78%) successfully treated with interval appendectomy had an overall 6.3% complication rate, and total hospitalization averaged 5.2 days. The treatment in 21 of 22 patients (22%) requiring early appendectomy failed because of a clinical picture suggesting small bowel obstruction. The patients with the failed procedures had a complication rate of 50% and were hospitalized an average of 12.8 days. The overall complication rate for the 101 patients was 15.8%, and the overall total hospitalization was 6.9 days. Patients requiring early appendectomy had a more frequent finding resembling a small bowel obstruction on their initial x-ray (50% v 13%, P =.004) and a higher percent band count on their initial differential blood cell count (22.6% v 7.6%, P Conclusions: Interval appendectomy without complications is successful in the majority of patients with perforated appendicitis. An elevated initial band count ≥15% is associated with an increased likelihood of failure and complications. J Pediatr Surg 36:165-168. Copyright © 2001 by W.B. Saunders Company.
The AMS program at LLNL

Livermore will have an operational accelerator mass spectrometer (AMS) by mid-1989 as part of its new Multi-user Tandem Laboratory. The spectrometer was designed primarily for applications in archaeology and the geosciences and was co-funded by the University of California Regents. Radiological control for personnel protection, ion sources and injection systems, the tandem and all beam handling hardware are operated with a distributed processor computer control system. The tandem is the former University of Washington injector FN which has been upgraded with Dowlish tubes, pelletron charging and SF6 gas. Design goals for the AMS system, computer aided operation, automated measurement capability, initial results and some of our intended applications will be presented.
Recent MTI experiments using ARL's synchronous impulse reconstruction (SIRE) radar

The Army Research Laboratory (ARL) has recently developed the ground-based synchronous impulse reconstruction (SIRE) radar - a low-frequency radar capable of exploiting both a real antenna array and along-track integration techniques to increase the quality of processed imagery. We have already demonstrated the system's utility by imaging static scenes. In this paper we address the moving target indication (MTI) problem, and we demonstrate the impulse-based system's ability to both detect and locate slowly moving targets. We begin by briefly describing the SIRE system itself as well as the system configuration utilized in collecting the MTI data. Next we discuss the signal processing techniques employed to create the final MTI image. Finally, we present processed imagery illustrating the utility of the proposed method.
IMPLEMENTING MEMRISTOR BASED CHAOTIC CIRCUITS

This paper provides a practical implementation of a memristor based chaotic circuit. We realize a memristor using off-the-shelf components and then construct the memristor along with the associated chaotic circuit on a breadboard. The goal is to construct a physical chaotic circuit that employs the four fundamental circuit elements — the resistor, capacitor, inductor and the memristor. The central concept behind the memristor circuit is to use an analog integrator to obtain the electric flux across the memristor and then use the flux to obtain the memristor's characterstic function.
Mapping the magnetic mayhem in the heliosheath

[1] When Voyager 1 passed into the heliosheath in 2004, it became the first human-made object to explore the remote edge of the Sun's magnetic influence. The heliosheath, between 1.5 and 15 billion kilometers thick and starting roughly 14 billion kilometers from the Sun, is where the outgoing flows of solar wind start to be pushed back by interstellar particles and magnetic fields that are heading toward the solar system. While passing through the heliosheath, Voyager 1 experienced many sudden and drastic changes in the surrounding magnetic field driven by structures called current sheets. Using Voyager 1's ongoing measurements of the magnetic field, Burlaga and Ness identified three distinct types of current sheets. The structures, appearing as proton boundary layers (PBLs), magnetic holes or humps, or sector boundaries, were identified by characteristic fluctuations in either magnetic field strength or direction as the spacecraft crossed nearly 500 million kilometers of heliosheath in 2009. PBLs are defined by a rapid jump in magnetic field strength, with one observed event resulting in a doubling of the field strength in just half an hour. Passing through a sector boundary led to a sudden change in direction of the magnetic field. Magnetic holes saw the field strength drop to near zero before returning to the original background strength. Magnetic humps consisted of a sudden spike in strength and then a return to initial levels. (Journal of Geophysical Research-Space Physics, doi:10.1029/2010JA016309, 2011)
CVC syllables for investigating the phonetic sensitivity of Mandarin and English speakers.

Although many individual speech contrasts pairs have been studied within the cross-language literature, no one has created a comprehensive and systematic set of such stimuli. This article justifies and details an extensive set of contrast pairs for Mandarin Chinese and American English. The stimuli consist of 180 pairs of CVC syllables recorded in two tokens each (720 syllables total). Between each CVC pair, two of the segments are identical, whereas the third differs in that a segment drawn from a “native” phonetic category (either Mandarin, English, or both) is partnered with a segment drawn from a “foreign” phonetic category (normative to Mandarin, English, or both). Each contrast pair differs by a minimal phonetic amount and constitutes a meaningful contrast among the world’s languages (as cataloged in the UCLA Phonological Segment Inventory Database of 451 languages). The entire collection of phonetic differences envelops Mandarin and English phonetic spaces and generates a range of phonetic discriminability. Contrastive segments are balanced through all possible syllable positions, with noncontrastive segments being filled in with other “foreign” segments. Although intended to measure phonetic perceptual sensitivity among adult speakers of the two languages, these stimuli are offered here to all for similar or for altogether unrelated investigations.
The determination of plasma fibrinogen by turbidity with ammonium sulfate.

Abstract A method of fibrinogen analysis by turbidity with (NH4)2SO4 is described, and its potential diagnostic value is indicated.
College Students' Preferences for Psychotherapy Across Depression, Anxiety, Relationship, and Academic Problems

The present study examined differences in college students' preferences for processes of change across four kinds of problems: academic, relationship, depression, and anxiety. Two hundred eighteen undergraduates were randomly assigned to complete either an academic problems, relationship problems, depression, or anxiety Processes of Change Questionnaire along with the Attitudes Toward Seeking Professional Psychological Services Scale. Results revealed significant differences for preferred processes of change as a function of problem type. Generally, processes of change were more preferred for depression, anxiety, and relationship problems than for academic problems. Results may assist clinicians in selecting psychotherapeutic interventions to which college students will be most receptive.
A model for the molecular requirements of immunoglobulin heavy chain class switching

Heavy chain immunoglobulin gene expression requires two independent DNA recombination systems1–3. The first DNA rearrangement event (V–D–J recombination) involves the formation of a complete variable region (VH) gene in pre-B lymphocytes3–6. The second series of recombination events allows for a switch in heavy chain constant region class from μ to either γ3, γ1, γ2b, γ2a, ɛ or α1–3. These recombination events occur in intervening sequences but do not alter or generate new coding information which is a common feature of V–D–J unions1–3. Tandemly repeated DNA sequences, spanning ∼2–5 kilobases (b), are localized ∼1.5 kilobase pairs 5′ of each CH gene and have been termed CH switch (S) regions.2,7. Two short, simple sequences that are shared by all switch region repeats (GAGCT and GGGGT) have been proposed to facilitate CH switching by homologous DNA recombination8. Unlike other switch regions, a large portion of the Sμ region (3 kb) consists of essentially pure tandem repeats of GAGCT which are occasionally interrupted by a GGGGT8. However, the precise sites of switch-recombination in Sμ are generally located considerably 5′ of this genetically unstable stretch9,10 of GAGCT repeats (Fig. 1). We now report the properties of a novel CH S region sequence, YAGGTTG, which is 5′ of switch recombination sites and preferentially repeated in S regions.
Light Scattering by Nonspherical Particles: A Laboratory Study

The concept of dividing the light scattered by nonspherical particles into three components—diffracted, refracted and reflected—is discussed here, using a set of measured phase functions, for the case of monodisperse aerosol particles. A logical scheme is developed that allows a simple representation of the light scattering properties of classes of nonspherical particles in a region where geometric optics is not expected to be valid. In the limits of this analysis, it appears that the equations developed can be applied to larger varieties of problems where there is a need to infer the optical properties of nonspherical particles.
Detection of small surface-breaking fatigue cracks in steel using scattering of Rayleigh waves

The long-wavelength (Rayleigh) scattering of a 5 MHz ultrasonic pulse propagating at the surface of a sample under cyclic tensile loading is used to monitor the growth of small surface-breaking cracks. The scattered signals are used to detect the presence of cracks as small as 80 μm in length, in the specimens made of AISI 4130 steel, even in the presence of strong curvature of the surface in the path of the Rayleigh waves. Ultrasonic data is recorded as a function of the number of cycles and compared with crack length measured optically with a microscope. Experiments indicate that the rms amplitude of the scattered signal is proportional to the square of the crack radius measured optically. On specimens with rougher surfaces, ultrasonic detection occurs before optical detection of the cracks. Results also indicate that the short-time Fourier transform (STFT) may be useful to determine whether a single crack (high cycle fatigue) or a distribution of cracks (low cycle fatigue) is present.
Low cost computer graphics in engineering education

Abstract The Apple II is a personal computer which provides 6 color, raster graphics via a 280 h × 192 v frame buffer. A user-programmable MOS Technology 6502 CPU addresses 48 K bytes of RAM, 12 K of ROM. and 4 K of memory-mapped I/O. This system has been evaluated in a variety of applications for which one normally assumes higher resolution, higher cost graphics devices are needed. Examples were drawn from computer aided design, color microfilm previewing, cartography, and aircraft synthesis. The results were encouraging: low resolution raster scan graphics is surprisingly effective for a wide range of applications. As a result, a computer graphics laboratory, with a cluster of 10 Apples as its nucleus, was formed and has been functioning successfully for 4 terms.
A bibliography of monographic works on biomaterials and biocompatibility : Update

This bibliography includes monographs published from 1996 to 1998 and serves to update two previous bibliographies by the same title that together covered the years 1973 to 1995. All three bibliographies are indexed as a combined work by conference titles, series titles, and names of associated corporate bodies including professional society, research institute, and government agency names.
Biogeographic anomaly or human introduction: a cryptogenic population of tree skink (Reptilia: Squamata) from the Cook Islands, Oceania

Archaeological and molecular data have revealed that the present day faunas of many island groups in Melanesia, Polynesia, and Micronesia are not representative of the biodiversity generated within this region on an evolutionary timescale. Erroneous inferences regarding the mechanisms of speciation and the significance of long distance dispersal in shaping the present diversity of these island systems have resulted from this incomplete diversity and distributional data. The lizard fauna east of Samoa has been suggested to derive entirely from human-mediated introductions, a distribution congruent with biogeographic patterns for other Pacific species. Distinguishing between introduced populations and those that result from natural colonization events is difficult, although molecular data provide a useful means for elucidating population history and identifying the likely sources of introductions. We use molecular data (1726 bp of mitochondrial DNA and 286 bp of nuclear DNA) to evaluate a population of arboreal lizards from the Cook Islands and to determine whether this arboreal skink population is the sole endemic component of the lizard fauna east of Samoa or the result of human-mediated introduction. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 318–328.
Pretzels with a Purpose: The Role of Christianity in the Auntie Anne's Brand

Auntie Anne's pretzel company began in 1988 as a single stall in a Pennsylvania farmer's market. Founder and owner Anne Beiler grew up in a Lancaster County Amish­Mennonite community and sought to embed her religious values within the business. Once FOCUS Brands Inc., an affiliate of Roark Capital Group, purchased the company in 2010, the business maintained success through the perception that the Auntie Anne's brand had a higher purpose beyond profit. This business performs as an example of Christianbased companies that can expand successfully in the United States and abroad by projecting an altruistic image. Auntie Anne's marketing materials and employee opportunities imply that working for or buying their products contributes to ethical and Christian consumption. But the company does not clearly abide by Christian principles in all aspects of business. Instead, the benevolence of Auntie Anne's is created by its executives rather than represented through tangible actions. Bread products are laden with religious associations. According to many scholars, "Food has long ceased to be merely about sustenance and nutrition. It is packed with social, cultural, and symbolic meanings."[1] Bread is important to Christians as the figurative body of Jesus. Muslims eat bread at the celebration following the month­long fast of Ramadan. Jews have challah for Shabbat and matzo for Passover. In this way, Auntie Anne's utilized the pre­existing connotations of bread to create spiritual significance in their pretzel product.
New Deal Regulation and the Revolution in American Farm Productivity. A Case Study of the Diffusion of the Tractor in the Corn Ielt, 1920–1940

Based on the cost savings of tractors relative to horses, nearly twice as many farmers in the Corn Belt should have invested in tractors as actually did so in the 1920s. During the Great Depression, however, the proportion of farmers owning tractors jumped from 25 to 40 percent. I argue that financial barriers explain farmers' reluctance to buy this expensive invention during the 1920s, while two New Deal regulatory agencies altered farmers' investment climate and spurred the adoption of capital equipment.