cssi/SciSciGPT-SciSciNet huggingface dataset:
Probability-based seismic response analysis

A procedure to account for the uncertainty in the characteristics of future ground motions during seismic response assessment is presented. In the proposed procedure, the probability of exceedance of structural response parameters conditioned to a given ground motion intensity is computed from a series of deterministic response history analyses at three loading intensity levels. The proposed procedure explicitly takes into account the variation of dispersion of the structural response with changes in the loading intensity. Regression analyses are conducted on the parameters of the conditional probability distribution in order to estimate the conditional probability of exceedance at other ground motion intensity levels. Results are then combined with probabilistic estimates of seismic loading in order to estimate the mean annual rates of exceedance of various structural response parameters. The proposed procedure is evaluated when applied to an existing seven-story reinforced concrete building. Results are also compared to those obtained with an existing simplified procedure. The effect of various simplifying assumptions made in the existing simplified solution are also evaluated. It is shown that neglecting variations in dispersion in some cases can lead to significant errors. It is concluded that the proposed procedure provides more accurate results than the simplified approach with only a minimum additional computational effort.
De-Academizing Early Childhood Research: Wanderings of a Chicana/Latina Feminist Researcher

In this article, I frame critical questions about discourse and power when centering marginalized populations in research. This critical Chicana feminist analysis of early childhood research illuminates (a) the bifurcation of the academy and the comunidad, (b) voice as ilusion, (c) research as colonization, and (d) the United States' cultural invention of universal needs. Destrenzando (unbraiding and unraveling) research foregrounds and interweaves the personal, political, historical, and cultural into a messy text. In this messy text, the initial subject of our gaze is the participants, but it ultimately ricochets back to the researcher, our research methods, and to questions of (de)colonization.
Distribution of phosphorylated GAP‐43 (neuromodulin) in growth cones directly reflects growth cone behavior

Phosphorylation of GAP-43 (neuromodulin) by protein kinase C (PKC) occurs at a single site, serine41. In vivo, phosphorylation is induced after initiation of axonogenesis and is confined to distal axons and growth cones. Within individual growth cones, phosphorylation is nonuniformly distributed. Here, we have used high-resolution video-enhanced microscopy of cultured dorsal root ganglia neurons together with immunocytochemistry with a monoclonal antibody that recognizes PKC-phosphorylated GAP-43 to correlate the distribution of phosphorylated GAP-43 with growth cone behavior. In "quiescent," nontranslocating growth cones, phosphorylated GAP-43 was confined to the proximal neurite and the central organelle-rich region, and was low in organelle-poor lamellae. However, levels in lamellae were elevated when they became motile. Conversely, levels of phosphorylated GAP-43 were low in either lamellae that were actively retracting or in the central organelle-rich region and proximal neurite of growth cones that had totally collapsed. The results suggest a mechanism whereby phosphorylation of GAP-43 by PKC, potentially in response to extracellular signals, could direct the functional behavior of the growth cone.
The association of coronal mass ejection transients with other forms of solar activity

Coronal mass ejection transients observed with the white light coronagraph on Skylab are found to be associated with several other forms of solar activity. There is a strong correlation between such mass ejection transients and chromospheric Hα activity, with three-quarters of the transients apparently originating in or near active regions. We infer that 40% of transients are associated with flares, 50% are associated with eruptive prominences solely (without flares), and more than 70% are associated with eruptive prominences or filament disappearances (with or without flares). Nine of ten flares which displayed apparent mass ejections of Hα-emitting material from the flare site could be associated with coronal transients. Within each class of activity, the more energetic events are more likely to be associated with an observable mass ejection.
Measurement of Firm Diversification: Is It Robust?

This study investigated the convergent validity of Rumelt’s categorical classification of types of business diversification across different data sources and variations from Rumelt’s method. The st...
Bullectomies for bullous sarcoidosis.

A 36-year-old woman presented with respiratory insufficiency due to cystic sarcoidosis. She had been previously treated with multiple courses of prednisone without improvement. Enlarging blebs involving both lower lobes impaired the function of the relatively spared upper lobes. Bilateral lower lobectomies were performed in one step via median sternotomy without complications, with prompt subjective and objective improvement of her respiratory status. One-stage bilateral upper-lobe bullec-tomy for bullous emphysema has been previously reported, but to our knowledge this is the first performance of one-stage bilateral lower-lobe bullectomies for cystic sarcoidosis. The immediate benefits were evident; long-term results will depend on the course of the underlying disease.
Modification of carboxyl groups in the active site of trypsin.

Abstract The chemical modification of carboxyl groups in chromatographically homogeneous bovine β-trypsin using the carbodiimide-nucleophile procedure resulted in complete loss of enzyme activity and the modification of 8 carboxyl groups. Under similar reaction conditions, the presence of a competitive inhibitor was found to decrease both the extent of modification and the loss of activity, giving a product with 7 carboxyls modified and 30% of the original activity. The carboxyl group protected to the largest extent was identified as Asp-177, with Asp-182 being protected to a lesser extent. Direct evidence is also presented indicating that residue 177 is indeed aspartic acid rather than asparagine.
Methamphetamine activates nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and induces human immunodeficiency virus (HIV) transcription in human microglial cells

Human immunodeficiency virus (HIV) primarily infects glial cells in the central nervous system (CNS). Recent evidence suggests that HIV-infected individuals who abuse drugs such as methamphetamine (METH) have higher viral loads and experience more severe neurological complications than HIV-infected individuals who do not abuse drugs. The aim of this study was to determine the effect of METH on HIV expression from the HIV long terminal repeat (LTR) promoter and on an HIV integrated provirus in microglial cells, the primary host cells for HIV in the CNS. Primary human microglial cells immortalized with SV40 T antigen (CHME-5 cells) were cotransfected with an HIV LTR reporter and the HIV Tat gene, a key regulator of viral replication and gene expression, and exposed to METH. Our results demonstrate that METH treatment induced LTR activation, an effect potentiated in the presence of Tat. We also found that METH increased the nuclear translocation of the nuclear factor kappa B (NF-κB), a key cellular transcriptional regulator of the LTR promoter, and the activity of an NF-κB-specific reporter plasmid in CHME-5 cells. The presence of a dominant-negative regulator of NF-κB blocked METH-related activation of the HIV LTR. Furthermore, treatment of HIV-latently infected CHME-5 (CHME-5/HIV) cells with METH induced HIV expression and nuclear translocation of the p65 subunit of NF-κB. These results suggest that METH can stimulate HIV gene expression in microglia cells through activation of the NF-κB signaling pathway. This mechanism may outline the initial biochemical events leading to the observed increased neurodegeneration in HIV-positive individuals who use METH.
High school student attitudes about physical education

This study examined attitudes of high school students toward fitness and sports activities taught in physical education, and the perceived effectiveness of their physical education curriculum for improving their fitness and skill levels. Students from six high schools and 17 intact physical education classes agreed to participate. Data were collected using a questionnaire completed by 515 students, 159 of whom participated in focus group interviews. Results indicated student preference for a wider variety in sport and fitness activities, an increase in level of challenge in physical education classes, and an increase in student motivation for participating in activities outside of school. Student attitudes were accepting or tolerant of participation in fitness activities due to known health benefits. Most students liked physical education class that included some form of game play. In addition, they stressed the need for adding interesting activities that included active participation while having fun. St...
Multiple positive and negative elements regulate human brain creatine kinase gene expression

We characterized the developmental expression of the brain creatine kinase (BCK) gene in the C2C12 myogenic cell line with the use of isoenzyme, Western blot, and Northern blot analyses. The results show that both BCK subunit protein and mRNA are upregulated early in myogenesis, and then downregulated in fully differentiated myotubes. To characterize the transcriptional regulatory mechanisms, a chimeric construct containing 1.2 kilobase pairs of 5'-flanking DNA from the human BCK gene placed upstream of the chloramphenicol acetyltransferase gene in the promoterless plasmid pSVOCAT was transiently transfected into C2C12 cells. In myoblasts and differentiating myotubes, the time course of expression of the constructs paralleled that of endogenous BCK mRNA. Additional constructs prepared by deleting 5'-flanking DNA were also transfected into C2C12 cells. All constructs were preferentially expressed in myoblasts relative to myotubes with absolute levels of expression increasing with deletion of 5'-flanking DNA. In nonmyogenic cells expression of the plasmids also increased with deletion of 5'-flanking DNA. An element from -1150 to -388 was isolated and found to be capable of suppressing expression of the BCK promoter and of heterologous promoters independent of orientation and position and hence to function as a silencer. Thus, BCK expression is mediated by sequences contained in the 5'-flanking DNA, including negative elements active in both C2C12 cells and nonmyogenic cells and elements that mediate the developmental expression of the BCK gene in C2C12 myogenic cells.
Natural codeswitching knocks on the laboratory door

This contribution discusses findings and hypotheses from empirical data of naturally-occurring codeswitching. The discussion is framed by some comparisons of the approaches of contact linguists and psycholinguists to bilingual production data. However, it emphasizes the relevance of naturally-occurring codeswitching to the theoretical questions asked by psycholinguists. To accomplish this, relevant grammatical structures in codeswitching are exemplified and analyzed. Analysis largely follows the Matrix Language Frame (MLF) model, but differing approaches are mentioned.
Long term antipsychotic treatment does not alter metabolite concentrations in rat striatum: An in vivo magnetic resonance spectroscopy study

Proton magnetic resonance spectroscopy (MRS) studies of schizophrenic patients generally reveal reduced levels of N-acetyl aspartate (NAA) when compared with healthy controls. Whether this reduction is due to the disease or to the drugs used for treatment remains an open question. Numerous human and animal studies have attempted to determine the effects of antipsychotics on NAA levels with mixed results. The majority of the animal studies were ex vivo, which may not accurately reflect the in vivo situation, and limitations of the human studies include previous or concomitant medications or other confounds. To overcome these limitations, we dosed 10 rats/group for six months via drinking water with 0.2 or 2 mg/kg/day haloperidol or 10 or 30 mg/kg/day clozapine. Control rats received unadulterated water. Proton MRS data were collected longitudinally over the six month period from a 64 μL voxel containing primarily the right striatum prior to and monthly during drug administration and used to estimate the concentrations of NAA, creatine, and choline. Ratios of NAA, choline, inositol and glutamate+glutamine to creatine were also calculated. Only the Cho/Cr ratio showed a significant time-by-treatment effect (p=0.0285). These results are in agreement with previous studies of the striatum. However, regional and disease-specific effects remain unresolved.
Development of stress/strain curves for 80In15Pb5Ag

Experimental studies relating stress to strain under large strain conditions were conducted for 80In15Pn5Ag, at strain rates of 0.21 × 10−3 s−1, 0.42 × 10−3 s−1, and 2.1 × 10−3 s−1; and at temperatures of −65, 0, 25, 75, 100, and 125°C. The ultimate tensile stress of 80In15Pb5Ag as a function of temperature and strain rate was plotted. Similar measurements were made using 63Sn37Pb as a baseline comparison. Tin/lead eutectic was found to have a maximum tensile stress which was 50% higher than 80In15Pb5Ag at 25°C, and approximately 100% higher than 80In15Pb5Ag at 100°C. Under the same conditions, the ductility of 80In15Pb5Ag is always greater than that of 63Sn37Pb.
EPIDEMIOLOGIC MODELING USING A MICROCOMPUTER SPREADSHEET PACKAGE

Epidemiologic modeling has provided both researchers and students with a means of studying complex disease processes as well as making intervention recommendations to decision makers. To develop more than the most elementary model, however, it has become necessary to be well versed in a computer programming language. While this has deterred many modelers in the past, with microcomputers it is now possible to develop even complex models without significant investment of time spent in learning a computer language. In addition to being affordable, many microcomputers offer "canned" spreadsheet packages which are readily adapted for epidemiologic modeling. To demonstrate this, two models were developed and run using a microcomputer spreadsheet package: 1) the classic Reed-Frost model, and 2) a modified Reed-Frost model with two intermixing subpopulations.
Thought by Description

It seems perfectly obvious that we all very frequently have thoughts that are directed upon or are about particular objects in the external world, including other persons as well as a vast number of types of ordinary physical thing. But the problem of what makes our thoughts and other cognitive attitudes about particular objects is extremely difficult. The problem received much attention from many skilled philosophers from the 1960s until the mid-1980s. But since then, the problem has received scant attention, even though I think no general consensus had been achieved regarding the form that a correct solution should take.1
Lithium discharges in a microwave resonant cavity ion source

Lithium-argon plasmas have been produced in a microwave resonant cavity ion source at the University of Michigan. Lithium has been introduced into the system in the solid forms of LiCl and Li/sub 2/CO/sub 3/, which is then heated by a background argon discharge allowing dissociation of the lithium. The dissociation is evidenced by the observation of strong Li I lines in the discharge using optical emission spectroscopy. Input microwave powers of 100-250 watts have been used and discharges have been established with background argon pressures of 5-20 mTorr. Double Langmuir probe studies have indicated ion densities 1-5/spl times/10/sup 10//cm/sup 3/ and electron temperatures of 3-3.5 eV. A comparison of discharges created with LiCl and Li/sub 2/CO/sub 3/ will be made. Behavior of the discharge with varying initial amounts of Li/sub 2/CO/sub 3/ and argon pressures will be shown. Discussion of its use as a lithium ion source for thin film deposition will be presented as well.
3D object reconstruction from multiple views using neural networks

Automatic determination of 3D information from digital images is a fundamental problem in digital photogrammetry and computer vision. The most difficult task in the problem is finding conjugate points in images. Despite the wealth information contained in stereo images, factors such as occlusions and discontinuities challenge several algorithms implemented to match conjugate points. On the other hand, multi-image matching has gained considerable attention recently since it accounts for changes in illumination conditions, camera positions, and surrounding features. Currently, a wide variety of techniques have been developed for multi-image matching. However, most of these techniques are based on one of two approaches: grouping outputs from stereo matching or looking for corresponding points in all views. The first approach results in scenarios where several false matches could be grouped. The second approach is limited to cases where points appear in all views with comparable intensity values. This paper introduces an alternative algorithm to match image points across several views. Our approach is based on locating all sets of corresponding points in all image triplets using neural networks then grouping those triplet sets that represent the same ground point. Radiometric and geometric properties are fed into a feedforward neural network designed to detect valid matches from invalid ones in all image triplets simultaneously. The detection rate of the neural network is more than 98 % and the false alarm rate is less than 2 %. Triplet matching sets are then combined if they share the same image point and their image rays have a valid intersection as measured through the colinearity equation. In order to assess the geometrical accuracy of the 3D points, the image coordinates are manually measured in the original images and object coordinates are computed and found comparable to those computed through the proposed algorithm.
Linking shore with the ocean floor in real time in archeological oceanography

In ocean exploration, physically transporting human beings in small numbers to remote regions of the world, and then taking them to the bottom of the ocean in very smaller numbers for short periods of time to explore short stretches of the sea floor, is clearly a costly and inefficient way to explore these vast regions of our planet. Recently, however, during an expedition to the Black Sea, lnternet2 and a high-bandwidth satellite link made it possible for scientists to work on the ocean floor without ever having to leave the comfort of their university laboratory Internet2 is a consortium of 206 universities working with industry and the government to develop and deploy an advanced Internet network that operates at 10 gigabits per second. Its future goal is to offer 100 megabits per second via its Abilene backbone to its user base (see www.internet2.edu/about).
A COMPARISON OF TABLE-LITTERING BEHAVIOR IN TWO SETTINGS:A CASE FOR A CONTEXTUAL RESEARCH STRATEGY☆

Nearly 2000 persons and 1100 table occupancies were observed in two settings. The settings differed in that table littering in one was nearly twice that of the other. In both settings males littered more than females and littering was more likely at tables greater distance from littering containers. Importantly, the relationship between table littering and the variables of group size and group gender mix differed in the two settings, owing to the operation of variables specific to each setting. Tentative explanations were offered for the interactions between these variables and the setting. These results were seen as supportive of Stokols' view that theory building is best done with a contextual research strategy.
Effect of dual-chamber pacing on systolic and diastolic function in patients with hypertrophic cardiomyopathy Acute doppler echocardiographic and catheterization hemodynamic study

Objectives. This study sought to evaluate prospectively the acute hemodynamic effect of dual-chamber pacing by using a combined hemodynamic approach of high fidelity pressure and Doppler velocity measurements. Background. Dual-chamber pacing has been proposed recently as an alternative in the symptomatic treatment of patients with hypertrophic obstructive cardiomyopathy. Although early reports documented a decrease in left ventricular outflow tract gradient and symptomatic improvement, questions remain about the hemodynamic effects of dual-chamber pacing on systolic and diastolic function. Methods. Twenty-nine patients with hypertrophic cardiomyopathy underwent a combined cardiac catheterization and Doppler echocardiographic study during normal sinus rhythm and P-synchronous pacing at various atrioventricular (AV) intervals. High fidelity pressure measurements of left ventricular inflow and left atrial pressures, ascending aortic pressure, thermodilution cardiac output and Doppler mitral flow velocity curves were obtained to evaluate both systolic and diastolic left ventricular function. Results. During AV pacing at the shortest delay of 60 ms, there was a significant decrease in cardiac output (p < 0.05) and peak positive dP/dt (p < 0.05), an increase in mean left atrial pressure (p < 0.05) and a prolongation of τ, the time constant of relaxation (p < 0.05), compared with that during normal sinus rhythm. During pacing at the optimal AV delay (longest AV interval with pre-excitation), there was a similar trend, with deterioration in both systolic and diastolic function variables but of lesser magnitude than that during pacing at the shortest AV intervals. The deterioration in both systolic and diastolic function was present in 21 patients with and 8 without left ventricular outflow obstruction. There was a modest decrease in left ventricular outflow tract gradient from 73.3 ± 45.0 (mean ± SD) to 61.3 ± 40.5 mm Hg (p = 0.03) during dual-chamber pacing at the optimal AV delay compared with that during normal sinus rhythm. Conclusions. The acute effect of pacing the right atrium and ventricle may be detrimental to both systolic and diastolic function of the left ventricle, particularly at the short AV intervals. Further studies of the long-term effects of dual-chamber pacing in carefully performed randomized studies are needed.
Budgeting information resources: Some alternative approaches

As concern over public sector efficiency and effectiveness has grown, attention has turned to budgetingressurces not heretofore budgeted well. This paper foctlses upon one such resource--the information resource--and examines implications for the improvement of public services and management decisions. In the pas:, managers have not viewed information as a resource to be managed as we have human and financial resources. With the rapid growth of information technology and its increasing use, we are becoming more aware of the costs of information and the need to budget for information services. We argue that information resources should be visible, traceable and chargeable. Alternative styles of decision making/budgeting are identified built around two methods of information use: one is called the input-oriented approach, the other, the output-oriented approach. The input-oriented approach is based upon the concept of incrementalism while the output-oriented approach reflects the rationalistic decision styl...
Cerebral Fat Embolism Syndrome from Penetrating Trauma: A Rare Cause-and-Effect

A 42 year-old male sustained an accidental rifle gunshot wound to his left foot, resulting in fracture deformities of the calcaneus, navicular, cuneiform, 1st and 2nd metatarsal bases, and talus. As he was transported to our trauma center, he developed progressive encephalopathy. Urgent external fixator placement under general anesthesia was postponed due to his encephalopathy of unknown etiology. Brain magnetic resonance imaging demonstrated a “starfield” pattern of infarcts, consistent with cerebral fat embolism syndrome. Subsequently, he underwent uneventful general anesthesia. The patient was managed supportively and continued to have persistent neurologic dysfunction two months after injury.
Stress-Induced Increase in Kynurenic Acid as a Potential Biomarker for Patients With Schizophrenia and Distress Intolerance

Importance Several lines of evidence have linked the endogenous neuromodulator kynurenic acid (KYNA) to schizophrenia. The pathophysiology of schizophrenia is commonly associated with stress, and stress plays a key regulatory role in the first, rate-limiting step of the kynurenine pathway, which produces KYNA. Objective To determine whether the level of KYNA changes following psychological stress and whether this change is associated with stress-related behavior. Design, Setting, and Participants The KYNA level was measured in saliva samples taken at baseline and at 2 times following a laboratory-based psychological stress challenge in 128 participants (64 patients with schizophrenia from outpatient clinics and 64 healthy controls from the community). Exposure Laboratory-based psychological stress challenge. Main Outcomes and Measures Quitting the stressful task early was used as a behavioral marker of distress intolerance. Results Patients with schizophrenia showed a significantly higher rate of distress intolerance compared with healthy controls ( P = .003). Salivary KYNA levels increased significantly between baseline and 20 minutes following the stress task in both patients and controls (mean [SEM], 6.72nM [0.65nM] vs 8.43nM [1.05nM], respectively; P = .007). Patients who were unable to tolerate the stressful tasks and quit early showed significantly higher levels of KYNA than patients who tolerated the psychological stressor ( P = .02) or healthy controls ( P = .02). In patients with distress intolerance, KYNA elevation significantly correlated with the severity of clinical symptoms (ρ = 0.64; P = .008). Conclusions and Relevance Distress intolerance is more common in patients with schizophrenia. Patients with this behavioral phenotype have elevated salivary KYNA levels. This stress response behavior–linked biomarker may aid heterogeneity reduction in schizophrenia and other stress-related psychiatric conditions.
Total synthesis of calicheamicin .gamma.1I. 1. Synthesis of the oligosaccharide fragment

The first total synthesis of the calicheamicin γ 1 I oligosaccharide fragment in the form of its methyl glycoside (62) has been achieved. The synthetic challenge of the B-ring was recognized and studied initially, resulting in a novel and unique solution to the stereochemical problems posed involving a [3,3]-sigmatropic rearrangement of an allylic thionoimidazolide (111). This chemistry was initially worked out on a model for the ABC-ring system (47) and then successfully applied to the real system. The success of this synthesis has enabled the completion of the first synthesis of the natural product itself, calicheamicin γ 1 I (I), as will be described in the following papers in this issue
The mechanistic role of enhancer elements in eukaryotic transcription

Enhancer elements are short stretches of nucleotides operationally defined by their cis-acting ability to increase the transcription of nearby genes. They function relatively independently of position, orientation, and distance. Some show narrow tissue specificity while others permit constitutive expression in many different cell types. Although the first enhancer was described for simian virus 40 (SV40) more than five years ago, its mechanism of action has remained unclear. This review describes some of the models proposed to explain the physical role of enhancers in eukaryotic transcription.
Tuberculosis, drug resistance, and HIV/AIDS: A triple threat

The worldwide epidemics of tuberculosis (TB) and HIV/AIDS have been joined by an insidiously developing third epidemic of TB drug resistance. Fueled by the disruption of TB control programs and the explosive growth of HIV/AIDS, the presence of TB drug resistance, particularly multiple drug resistance, is worldwide and threatens the gains made in the past decades in the treatment of both TB and HIV. Although treatment success is possible, the diagnosis and treatment of drug-resistant TB is difficult. Advances in TB diagnosis and treatment have been minimal in the past 40 years, and there is an urgent need for wider distribution of available diagnostic technology and for the development and testing of newer rapid molecular diagnostic techniques and therapeutic agents. This review discusses current information about the distribution of multiple drug-resistant and newer extensively drug-resistant TB as well as available diagnostic and therapeutic strategies with an emphasis on the relationship between TB drug resistance and HIV/AIDS.
Trans-synaptic stimulation of cortical acetylcholine and enhancement of attentional functions: a rational approach for the development of cognition enhancers.

Activation and restoration of cholinergic function remain major foci in the development of pharmacological approaches toward the treatment of cognitive dysfunctions associated with aging and dementia. Our research has been guided by the hypothesis that (re)activation of cortical cholinergic inputs is achieved as a result of trans-synaptic disinhibition of basal forebrain cholinergic neurons. This approach depends on the ability of benzodiazepine receptor (BZR) inverse agonists to reduce the potency of GABA to block neuronal excitation. BZR inverse agonists were found to augment cortical ACh efflux through interaction with cognition-associated activation of this system. Cortical cholinergic inputs have been implicated in the processing of behaviorally significant stimuli, i.e., attentional functions. Using a recently developed and validated task for the measurement of sustained attention, or vigilance, administration of BZR inverse agonists were found to selectively increase the number of false alarms in intact animals. However, in animals with a 50-70%, but not > 90%, loss of the cortical cholinergic inputs, treatment with BZR inverse agonists alleviated the lesion-induced impairment in sustained attention and enhanced activated cortical ACh efflux. A rational development of cognitive enhancers will benefit from experiments in which cognitive and neuropharmacological variables are assessed simultaneously, thus allowing the analysis of interactions between cognition-associated neuronal activity and the neuronal and cognitive effects of putative cognition enhancers.
A study on the role of Nb in melt-spun nanocrystalline Nd–Fe–B magnets

Abstract The effect of Nb substitution on the thermal stability of melt-spun powders with near stoichiometric 2:14:1 composition of Nd 12 Fe 82− x Nb x B 6 ( x =0, 1.5 and 3) has been investigated. It has been found that the thermal stability is significantly improved with 1.5 at% Nb substitution. As compared with the ternary Nd 12 Fe 82 B 6 , the Nb-substituted Nd 12 Fe 80.5 Nb 1.5 B 6 powder exhibits remarkably increased coercivity ( H ci ) over a wide temperature range of 22–180°C. The temperature coefficient of coercivity ( β ) is reduced from −0.36%/°C at x =0 to −0.32%/°C at x =1.5. As a result of improved coercivity and its temperature dependence, the irreversible flux aging loss ( δ irr ), measured on the epoxy bonded magnets after being exposed at 180°C for 100 h, is also significantly decreased from −13.7% at x =0 to −5.0% with x =1.5. Microstructure studies using X-ray diffraction and transmission electron microscopy have shown a significant microstructure refinement with Nb substitution. Nb substitution also increases the amount of α-Fe phase in the alloys. For x =0, the average grain size of the magnetically soft phase (α-Fe) is 15 nm, while the hard phase (Nd 2 Fe 14 B) has an average grain size of 30 nm. The soft and hard magnetically phases are reduced to x =1.5 and 3. Enriched Nb along the grain boundaries is believed to be the main reason for the observed improved thermal stability in Nb-substituted powders.
Preparing Reagents: Time Dependence of HCl(v =1, J) Alignment Following Pulsed Infrared Excitation

We discuss the use of photon absorption as a means of aligning reagents for studies of dynamical stereochemistry. A linearly polarized infrared beam from an optical parametric oscillator prepares HCl(v = 1, J = 1), and the alignment is monitored at subsequent times by (2+1) resonance-enhanced multiphoton ionization. The degree of alignment oscillates in time caused by hyperfine quantum beats. Experimental observations are well matched by calculations that account for the presence of unresolved hyperfine structure. Following reagent preparation by optical pumping, a cumulative hyperfine-depolarization coefficient can be used to describe the effective reagent alignment in a subsequent chemical reaction.
Global Transitions of Proteins Explored by a Multiscale Hybrid Methodology: Application to Adenylate Kinase

Efficient and accurate mapping of transition pathways is a challenging problem in allosteric proteins. We propose here a to our knowledge new methodology called collective molecular dynamics (coMD). coMD takes advantage of the collective modes of motions encoded by the fold, simultaneously evaluating the interactions and energetics via a full-atomic MD simulation protocol. The basic approach is to deform the structure collectively along the modes predicted by the anisotropic network model, upon selecting them via a Monte Carlo/Metropolis algorithm from among the complete pool of all accessible modes. Application to adenylate kinase, an allosteric enzyme composed of three domains, CORE, LID, and NMP, shows that both open-to-closed and closed-to-open transitions are readily sampled by coMD, with large-scale motions of the LID dominating. An energy-barrier crossing occurs during the NMP movements. The energy barrier originates from a switch between the salt bridges K136-D118 at the LID-CORE interface and K57-E170 and D33-R156 at the CORE-NMP and LID-NMP interfaces, respectively. Despite its simplicity and computing efficiency, coMD yields ensembles of transition pathways in close accord with detailed full atomic simulations, lending support to its utility as a multiscale hybrid method for efficiently exploring the allosteric transitions of multidomain or multimeric proteins.
Phase Composition and Compatibilities in the Bi‐Sr‐Ca‐Cu Quaternary Oxide System at 800°C in Air

Subsolidus phase relations in the system (Bi-Sr-Ca-Cu)-O at 800°C were investigated via powder X-ray diffraction and electron probe microanalysis of solid-state reaction products. Two recently reported (Bi-Sr-Ca)-O phases were detected in quaternary assemlages and had the approximate cation stoichiometries of 9115 and 825. The only truly quaternary compound detected is the superconducting phase with the cation stoichiometry 2212. Tie lines, tie triangles, and compatibility tetrahedra involving this phase and the 2201 superconducting phase were determined. Both superconducting compounds exhibit small but detectable Sr-to-Ca solubility and are Sr-deficient with respect to the “ideal” formulas.
Recombinant human erythropoietin treatment: investigational new drug protocol for the anemia of the acquired immunodeficiency syndrome. Overall results.

Background: Anemia associated with human immunodeficiency virus infection may be due to reduced erythropoiesis related to the disease itself or to concomitant medications (eg, zidovudine). Clinical studies have shown recombinant human erythropoietin (r-HuEPO) to be effective in correcting the anemia of zidovudine-treated patients infected with human immunodeficiency virus with baseline serum erythropoietin levels of 500 U/L or less. A treatment investigational new drug protocol that provided r-HuEPO to 1943 anemic patients with the acquired immunodeficiency syndrome was studied. Methods: Enrollment criteria included a clinical diagnosis of acquired immunodeficiency syndrome, serum erythropoietin level of 500 U/L or less, hematocrit less than 0.300, and age of 12 years or more. The initial r-HuEPO dosage was 4000 U subcutaneously for 6 days each week. On the basis of response, the r-HuEPO dosage could be increased sequentially to 8000 U subcutaneously for 6 days per week. This was an open-label multicenter treatment protocol. A total of 1943 patients were treated by 510 investigators. Efficacy evaluations were based on the effect of r-HuEPO on hematocrit levels and transfusion requirements relative to baseline. Adverse experiences that were considered by the investigator to be possibly related to r-HuEPO therapy were collected to assess safety. Results: Therapy with r-HuEPO resulted in an increase in mean hematocrit from a baseline of 0.280 to 0.331 at week 12 and 0.338 at week 24. This increase was sustained throughout the course of the study to week 54. Overall, 40% of patients (769/1943) required at least one transfusion in the 6-week interval immediately preceding study entry (baseline). After 12 and 24 weeks of r-HuEPO treatment, corresponding percentages were 22% (311/1387) and 18% (119/650), respectively. Response to therapy, defined as an increase of 0.060 from baseline in hematocrit, with no transfusions within 28 days before achieving that hematocrit, was observed in 44% of patients. Adverse experiences not clearly related to acquired immunodeficiency syndrome were reported by 11% of patients. Conclusion: In a study population of 1943 anemic patients with acquired immunodeficiency syndrome treated with r-HuEPO, the hematocrit increased and blood transfusion requirements decreased. Therapy with r-HuEPO was well tolerated. (Arch Intern Med. 1993;153:2669-2675)
Market equilibrium impacts of agricultural technology adoption

Abstract This paper presents a model of adoption for a technology which augments the quality of a fixed, heterogeneous asset. The extent of adoption is derived and it is shown how the level of adoption is influenced by economic parameters. Aggregate conditions are developed to illustrate the indirect equilibrium effects of adoption-induced changes in supply. A numerical example is presented to show the direct and indirect effects of output and income policies on output supply, output price, input use, and agricultural sector profitability.
Identifiability of a generalized mabkov-polya damage model

In the present paper, certain random damage models are examined, such as the generalized MARKOV-POLY A (GMP), the Quasi-Binomial, and the Quasi-Hypergeo-metric, in which an integer random variable N is reduced to B. Following JANAEDAN (1973 b) who has characterized the Multivariate Hypergeometric distribution in terms of the Multinomial, we have shown that under the GMP damage model, the distributions of N and B both belong to the family of the generalised POLYA-EGGENBERGER (GPE) distributions. We have also shown that the damage model can be uniquely identified as the GMPD given that B and N belong to the same GPE family. A physical interpretation of the result is given
Assessment of Prospectively Randomized Patients Receiving Propranolol Therapy before Coronary Bypass Operation

Abstract Fifty patients receiving propranolol were randomized into two groups of 25 patients each. One group received the last dose of propranolol within 4 hours of operation and were on a regimen of 160 mg daily. The second group had propranolol discontinued 24 to 48 hours prior to operation. Two nonrandomized control groups consisted of 25 patients who had never had propranolol and 15 patients who were on a regimen of 160 mg or more and who were operated on for unstable angina. Blood levels of propranolol were obtained just prior to incision. Several hemodynamic variables were assessed prior to anesthetic induction, at peak response during the early anesthetic period, and at the termination of cardiopulmonary bypass. Strict criteria were enforced for the administration of inotropic agents and the incidence of myocardial injury in the various groups was tabulated. Significant differences were present in the form of lower pressure-rate products in the patients maintained on propranolol therapy. The incidence of inotropic support, however, was also higher within the subgroups of patients who had propranolol immediately prior to operation. When examined further, increased inotropic requirements existed in patients having 320 to 480 mg of propranolol just before operation; this finding correlated with serum propranolol levels measured at the time of operation. This tightly controlled study supports the maintenance of propranolol for its beneficial perioperative hemodynamic effects but suggests that maintenance of doses of 320 to 480 mg per day are associated with a greater duration and extent of action that may transiently affect early postoperative hemodynamic performance.
Effects of streptozotocin-induced diabetes on phosphoglyceride metabolism of the rat liver

We have studied the effect of streptozotocin (SZ)-induced diabetes on fatty acyltransferase and phospholipase enzyme activities involved in the synthesis and degradation of rat liver phosphoglycerides. Neither mitochondrial nor microsomal acyl-CoA: glycerol 3-phosphate acyltransferase (GPAT) activity was altered, although insulin treatment stimulated mitochondrial GPAT activity. However, microsomal acyl-CoA: 1-acylglycerol 3-phosphate acyltransferase (1-acyl-GPAT) activity increased (24–33 per cent, p<0.01) in the diabetic animals using 3 different acyl-CoA donors: palmitoyl-CoA, oleoyl-CoA and linoleoyl-CoA. SZ-induced diabetes also increased acyl-CoA:1-acylglycerol 3-phosphorylcholine acyltransferase (GPCAT) activity (38–45 per cent, p<0.01) with 3 different acyl-CoA donors: oleoyl-CoA, linoleoyl-CoA and arachidonoyl-CoA. 1-acyl-GPAT and GPCAT activity returned to normal with insulin treatment. In contrast to the increased activity of the microsomal fatty acyltransferases 1-acyl-GPAT and GPCAT, SZ-induced diabetes decreased mitochondrial phospholipase A2 activity and lysophospholipase activity (49–70 per cent, p<0.01). Insulin treatment of the diabetic rats corrected the decreased lysophospholipase and stimulated phospholipase A2 activity 35 per cent higher than controls. Since microsomal 1-acyl-GPAT and GPCAT are known to have higher activity toward unsaturated fatty acyl-CoA donors, the increased GPCAT activity coupled with the decreased lysophospholipase activity and the increased 1-acyl-GPAT activity in diabetes would tend to increase the formation of newly synthesized phospholipids containing unsaturated fatty acids. This mechanism plus the decreased fatty acid desaturase (4) may be the factors which alter the fatty acid composition of phosphoglycerides in diabetic rat liver microsomes.
High frequency GaN device-enabled CubeSat EPS with real-time scheduling

This paper describes the hardware and software architectures and experimental results of a flexible and scalable electric power system (EPS) for CubeSat applications. The EPS has the three flexible battery charging modules (FBCM) to charge the battery and the four flexible digital point of load (FDPOL) converters to drive loads. It uses the maximum power point tracking (MPPT) algorithm to maximize output power from the solar arrays along with the battery state of health and state of charge determination algorithms to determine the health of the Li-ion batteries. This paper also evaluates converter performance with GaN devices driven at high frequencies in order to reduce the size of the filter components and provide better control of the converters. Analysis of a sample load's transients and its voltage regulation, using a real-time operating system (RTOS), is also discussed briefly in this paper.
SYNTHESIS AND CHARACTERIZATION OF SILOXY-SUBSTITUTED DIENE AND DIENYL COMPLEXES OF THE RU(C5ME5) FRAGMENT

Abstract The reaction of a 2-siloxy-4-methyl-1,3-pentadiene with the Ru(C 5 Me 5 )Cl tetramer was observed to lead first to an isolable Ru(C 5 Me 5 )(η 4 -diene)Cl complex, which subsequently was found to lose HCl readily, leading to the expected Ru(C 5 Me 5 )(η 5 -2-siloxy-4-methylpentadienyl) complex. Both species have been characterized spectroscopically and through X-ray diffraction studies.
Validation and Standardization of a Goal‐Oriented, Quick‐Screening Geriatric Scale*

: A quick-screening device for use with geriatric patients was validated and standardized. The population consisted of 150 geriatric patients at Arizona State Hospital. All were screened, and a stratified random sample of 40 patients was drawn for the study. Ratings were obtained on the Parachek Geriatric Behavior Rating Scale (the experimental device) and the Plutchik Geriatric Rating Scale (the shortest recognized geriatric screening device currently in use), before and after treatment. Correlation of the the Parachek scale with the recognized scale was −.88, validating the Parachek scale as a shorter alternate. Criterion validity was also checked when results were compared to the therapists' judgment. Expectancy tables yielded cutting scores for future use of the Parachek scale in classifying patients for treatment programs. These cutting scores predicted correct placement for 74.5 per cent of the subjects tested. This scale provides a basis for goal-oriented treatment plans, and also for long-term statistical records of geriatric patients.
Holocene peatland carbon dynamics in Patagonia

Abstract Patagonian peatland ecosystems have received very little attention in the scientific literature despite their widespread distribution in the regional landscape and the anthropogenic pressure they experience from the peat extraction industry. The functioning of these southern peatlands is strikingly similar to that of northern peatlands, but they have developed under very different climate boundary conditions. Therefore, studying these ecosystems provides a unique opportunity to test ideas and hypotheses about the sensitivity of carbon-rich peat accumulating ecosystems to climate change, in addition to filling significant data and knowledge gaps. Here we provide a synthesis of detailed peat accumulation records for southern Patagonia using a combination of new peat-core analysis (from 4 sites) and a data review from previously published studies (from 19 sites). We also present the modern climate space (temperature, precipitation, and seasonality ranges) of Patagonian peatlands on the basis of modern peatland distribution and gridded climate data to discuss climate controls of Patagonian peatlands at the present and in the past by inference. Results indicated that Patagonian peatlands occupy a distinct climatological niche that corresponds to an end-member of the northern peatland climate domain, with a mild mean annual temperature (from 3 to 9 °C) and very weak temperature seasonality. We also found that Patagonian peatlands have been efficient land carbon sinks since their initiation, with a mean soil carbon density of 168 kg C m−2 ± 10%. The total carbon pool for these ecosystems was estimated at 7.6 GtC. Modeled peat addition rates to the catotelm in Patagonian peatlands were significantly higher than what has been reported for northern peatlands, but decay coefficients were similar between these two high-latitude regions. These results support the idea that long, mild growing seasons promote peat formation in southern Patagonia. At the regional scale however, the lack of correlation between climatic parameters and peat accumulation indices suggests that autogenic controlling factors might be at play. Overall, southern peatlands provide a unique opportunity for studying peatland–carbon–climate linkages under a new set of climatic conditions.