cssi/SciSciGPT-SciSciNet huggingface dataset:
Memristor system properties and its design applications to circuits such as nonvolatile memristor memories

Novel nonvolatile universal memory technology is essential for providing required storage for nano-computing. As a potential contender for the next-generation memory, the recently found “the missing fourth circuit element”, memristor, has drawn a great deal of research interests. In this paper, by starting from basic memristor device equations that assumes constant ion mobility, we develop a comprehensive set of properties and design equations for memristor based memories. Our analyses are specifically targeting key electrical memristor device characteristics relevant to, but not limited to, memory operations. However, like many nano devices, a small voltage drop across the memristor will yield an enormous electric field, which may produce significant highly nonlinear ionic transport that the linear drift assumption no longer holds for realistic memristors. Issues such as how to design circuits facing such nonlinear drift will be discussed. In addition, issues such as how to sense the memory states and perturbations during sensing will be addressed. In this paper, we demonstrate that we can successfully use the derived properties based on the linear drift model to design read and write circuits and analyze important data integrity and noise-tolerance issues for realistic nonlinear drift models.
Price Reporting in Experimental Markets

The spatial oligopoly model has been proposed as a method of explaining behavior in food markets, particularly in response to retail food price reporting systems. This paper presents an analysis of the effects of price reporting in experimental spatial duopoly markets with controlled buyer behavior. The experiments are designed to evaluate the impact of a changed information flow on the price decisions of oligopolistic sellers. The short-run theoretical predictions of the spatial model are largely consistent with experimental market results. Thus, the spatial oligopoly model is not rejected as an explanation of seller response to changed price information Rows. Le modele oligopolistique spatial a deja ete propose pour expliquer le comportement des marches alimentaires, tel que determine en particulier par les systemes d'inforrnation sur les prix au detail des aliments. Nous presentons une analyse des effets du systeme d'information sur les prix dans des marches duopolistiques spatiaux expermentaux dans lesquels le comportement des acheteurs est controle. Ces experiences sont conpes pour evaluer I'incidence d'un changement dans la transmission des informations sur les decisions des vendeurs oligopolistiques concernant les prix. Les previsions theoriques a court terme du modele spatial sont largement en accord avec les rksultats experimentaux. Ainsi, le modele oligopolistique spatial peut he retenu pour expliquer la reaction des vendeurs e des chan-gements sumenus dans la transmission des informations sur les prix.
Pin1 modulates the dephosphorylation of the RNA polymerase II C-terminal domain by yeast Fcp1

The reversible phosphorylation of serine and threonine residues N-terminal to proline (pSer/Thr–Pro) is an important signaling mechanism in the cell. The pSer/Thr–Pro moiety exists in the two distinct cis and trans conformations, whose conversion is catalyzed by the peptidyl–prolyl isomerase (PPIase) Pin1. Among others, Pin1 binds to the phosphorylated C-terminal domain (CTD) of the largest subunit of the RNA polymerase II, but the biochemical and functional relevance of this interaction is unknown. Here we confirm that the CTD phosphatase Fcp1 can suppress a Pin1 mutation in yeast. Furthermore, this genetic interaction requires the phosphatase domain as well as the BRCT domain of Fcp1, suggesting a critical role of the Fcp1 localization. Based on these observations, we developed a new in vitro assay to analyze the CTD dephosphorylation by Fcp1 that uses only recombinant proteins and mimics the in vivo situation. This assay allows us to present strong evidence that Pin1 is able to stimulate CTD dephosphorylation by Fcp1 in vitro, and that this stimulation depends on Pin1’s PPIase activity. Finally, Pin1 significantly increased the dephosphorylation of the CTD on the Ser5–Pro motif, but not on Ser2–Pro in yeast, which can be explained with Pin1’s substrate specificity. Together, our results indicate a new role for Pin1 in the regulation of CTD phosphorylation and present a further example for prolyl isomerization-dependent protein dephosphorylation.
Maximum likelihood estimator for report-to-track association

A widely used estimator for multi-target tracking, conventionally referred to as a maximum likelihood estimator, is analyzed. For the problem of locating closely spaced fixed, untagged objects using a noiseless sensor, the conventional estimator's mean and variance estimates are inconsistent, i.e. asymptotically biased. We propose an alternative maximum likelihood estimator that corrects this problem. This estimator uses a coherent sum over report to track associations to evaluate the track likelihood function. The resulting estimator is efficient in the sense that it achieves the Cramer-Rao lower bound (CRLB) on the variance asymptotically. A novel feature of this approach is that it entails estimation of track error correlations in addition to the variance estimates generated in the usual Kalman filter based methods. These motions are used to develop a filter for a pair of uncorrelated Brownian walkers. It successfully estimates the error correlations that must be present in an optimal filter.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Gateway to wellness: an occupational therapy collaboration with the national multiple sclerosis society.

SUMMARYOccupational therapy is well equipped to build wellness for people with disabilities, particularly when partnering with community agencies or organizations. This article describes the collaborative relationship with the National Multiple Sclerosis Society for the development of Gateway to Wellness, A Program for Individuals with Multiple Sclerosis. Using the metaphor of a journey, issues relating to the collaborative relationship include language and power, paths and directions, the model design and evaluation, and negotiating expansion. The authors conclude with a summary of recommendations for positive partnering between occupational therapy and organizations that serve persons with disabling conditions.
PI-control of dual duct systems: manual tuning and control loop interaction

Abstract Good HVAC control schemes in buildings help reduce energy use and maintain occupant comfort. To this end, PID (proportional integral derivative) controllers are widely used in commercial buildings to keep variables, such as temperature and pressure, at predefined setpoints. These controllers, when they do not include an autotune feature, must be carefully tuned. Also, interactions occurring among the control loops must be considered during the first fine-tuning phase, so one loop response is not improved to the detriment of another. This study concentrates on PI (proportional integral) control of dual duct systems. Three tuning methods were selected and tested on a small scale dual duct system with four decentralized control loops. Each controller was tuned according to the best performing set of tuning parameters, and the system was then operated under design conditions to observe the interactions among the control loops. The effects of interactions were examined through a poorly tuned controller in each loop, one controller at a time.
Low positive predictive value of the oral brush biopsy in detecting dysplastic oral lesions.

BACKGROUND: The authors evaluated the effectiveness of the oral brush biopsy technique as a diagnostic tool in detecting dysplastic oral lesions. METHODS: In this cross-sectional study, pathologic reports (n = 152) from the scalpel biopsies (tissue samples) in patients who previously tested either “positive” (n = 3) or “atypical” (n = 149) for dysplasia by brush biopsy (OralCDx) were evaluated. Information on the age and sex of the patient, the site of the lesion, the brush biopsy results, and the histopathologic diagnosis of the scalpel biopsy was collected. The positive predictive values (PPVs) for “abnormal,” “atypical,” and “positive” brush biopsies were determined. RESULTS: Overall, the PPV of an abnormal brush biopsy was only 7.9% (95% confidence interval [CI], 4.2%-13.4%), and the PPV of an “atypical” brush biopsy was 7.4% (95% CI, 3.7%-12.8%). Of the 3 positive brush biopsies, only 1 was identified as dysplastic. The proportion of false-positive biopsy results was as high as 92.1% (95% CI, 86.6%-95.9%). CONCLUSIONS: The OralCDx technique overestimated dysplastic lesions and produced a high number of false-positive results. Cancer 2009. © 2009 American Cancer Society.
Social ideologies and gifted education in today's schools

The myth that children are born gifted and therefore can make it on their own is the belief that most affects the perceptions of the public regarding the gifted student and, too often, the actions of educators. From such a belief comes much of the antagonism toward providing differentiated learning experiences for gifted students and the notion that excellence and equity are separate and contradictory concepts. As a result, the limits to support for gifted learners reflect a lack of accurate knowledge, not a lack of commitment to children. Members of society and even educators still hold beliefs and attitudes that result in actions that are often damaging to the optimal growth of bright children. Data relevant to these beliefs suggest a view that is more in keeping with current biological and genetic research. It is this perception—the interactive and dynamic development of intelligent—that provides the basis for this article. The issues of equity, democratic ideals, and human rights must be reemphasized ...
Learning and nuclear safety: New reactors and US regulation

Abstract Gathering and analyzing data from operating reactors has become part of government and industry programs to improve performance in plants already on line and to inform development of future reactors. In the United States, however, early development and certain other factors combined to encourage a bias in learning. Regulation and learning from operational data intersect in ways that limit participation, data collection, and positive response to findings. Past learning has shown the advantage of simpler more standard designs with passive or inherent safety features. However, even designs incorporating these past lessons are apt to face tough regulatory tests and much criticism as operating experience is gathered. Only the operational success of new standardized reactors is apt to help rationalize regulation.
Flow Cytometry Protocols, 2nd edition. Methods in Molecular Biology, Volume 263. Teresa S. Hawley and Robert G. Hawley, editors. Totowa, NJ: Humana Press, 2004, 448 pp, $99.50, softcover. ISBN 1-588-29-235-5.

This is a well-updated second edition that has been designed and organized for both the novice and experienced cytometrist. The majority of the chapters are aimed primarily for the experimentalist with minimal experience with flow cytometric procedures, although a few discuss relatively advanced topics and specific methodologies such as fluorescence resonance energy transfer (FRET) and fluorescence in situ hybridization analysis by flow cytometry. The introductory chapter by Alice Givan provides a good general description of theoretical and practical aspects, and this overview is well supplemented by a chapter by Carleton and Sigrid Stewart on light and fluorescence scatter displays, gating analyses, and multicolor acquisitions. Several chapters address the analysis of intracellular constituents. A chapter by Perez et al. discusses methods for analyzing phosphoproteins, specifically kinase signaling cascades. Presentation of the different protocols for fixation and permeabilization will be especially helpful to the inexperienced reader. The figures display some of the differences that can be observed, but data in some figures may not be adequately …
Molybdoproteomes and evolution of molybdenum utilization

The trace element molybdenum (Mo) is utilized in many life forms, and it is a key component of several enzymes involved in nitrogen, sulfur, and carbon metabolism. With the exception of nitrogenase, Mo is bound in proteins to a pterin, thus forming the molybdenum cofactor (Moco) at the catalytic sites of molybdoenzymes. Although a number of molybdoenzymes are well characterized structurally and functionally, evolutionary analyses of Mo utilization are limited. Here, we carried out comparative genomic and phylogenetic analyses to examine the occurrence and evolution of Mo utilization in bacteria, archaea and eukaryotes at the level of (i) Mo transport and Moco utilization trait, and (ii) Mo-dependent enzymes. Our results revealed that most prokaryotes and all higher eukaryotes utilize Mo whereas many unicellular eukaryotes including parasites and most yeasts lost the ability to use this metal. In addition, eukaryotes have fewer molybdoenzyme families than prokaryotes. Dimethylsulfoxide reductase (DMSOR) and sulfite oxidase (SO) families were the most widespread molybdoenzymes in prokaryotes and eukaryotes, respectively. A distant group of the ModABC transport system, was predicted in the hyperthermophilic archaeon Pyrobaculum. ModE-type regulation of Mo uptake occurred in less than 30% of Moco-utilizing organisms. A link between Mo and selenocysteine utilization in prokaryotes was also identified wherein the selenocysteine trait was largely a subset of the Mo trait, presumably due to formate dehydrogenase, a Mo- and selenium-containing protein. Finally, analysis of environmental conditions and organisms that do or do not depend on Mo revealed that host-associated organisms and organisms with low G+C content tend to reduce their Mo utilization. Overall, our data provide new insights into Mo utilization and show its wide occurrence, yet limited use of this metal in individual organisms in all three domains of life.
Life change, health status and life satisfaction: A reconsideration

Recent research has suggested that life changes may be unrelated to health status indices and to overall satisfaction with life. Yet research has also reported that life changes appear to be related to measures of psychological distress. To attend further to clarification of the role of life change as a predictor of health status and life satisfaction, this paper examines the relationship between negative life change self-reports and indices of health status and life satisfaction. The data come from a survey of 1423 Northwestern Wisconsinites interviewed in 1974 by the Wisconsin Survey Research Laboratory. The findings indicate that self-reports of negative life changes were related to overall life satisfaction, controlling for health status, feelings of alienation/attachment, and personal disruption. Implications of the findings are discussed in conclusion.
Electrographic diagnosis of perforation of the heart by pacing catheter electrode.

Abstract The diagnosis of catheter perforation of the heart was strongly suspected in 6 patients with permanent implanted pervenous pacemakers. The diagnosis was confirmed in 2 cases by recording characteristic sequential electrograms from the electrode tip during the withdrawal of the catheter from the extracardiac position. In all cases ventricular pacing was reinstituted by the withdrawal and repositioning of the catheter without untoward effects. This method of treatment, which carries a small but definite risk of hemopericardium and cardiac tamponade, should preferably be performed where adequate facilities for immediate pericardiocentesis and thoracotomy are available.
Anger effects on driver situation awareness and driving performance

Research has suggested that emotional states have critical effects on various cognitive processes, which are important components of situation awareness Endsley, 1995b. Evidence from driving studies has also emphasized the importance of driver situation awareness for performance and safety. However, to date, little research has investigated the relationship between emotional effects and driver situation awareness. In our experiment, 30 undergraduates drove in a simulator after induction of either anger or neutral affect. Results showed that an induced angry state can degrade driver situation awareness as well as driving performance as compared to a neutral state. However, the angry state did not have an impact on participants' subjective judgment or perceived workload, which might imply that the effects of anger occurred below their level of conscious awareness. One of the reasons participants showed a lack of compensation for their deficits in performance might be that they were not aware of severe impacts of emotional effects on driving performance.
The effect of futures trading on price variability in the market for onions

This paper is in part a study of the operation of futures markets. The empirical evidence presented suggests that futures markets do reduce price fluctuations of traded commodities. Despite these facts, Congress eliminated futures trading in onions at the request of onion growers and shippers. As is often the case with political actions, the losses from the law are spread over a large number of individuals who do not have the incentive to become informed or to lobby on the matter, while the gains accrue to a smaller group with sufficient interest to lobby. Thus, in addition to shedding some light on the operation of futures markets, this paper is also a new illustration of an old maxim in political economy. Over 200 years ago, Adam Smith [11, p. 128] noted, “People of the same trade seldom meet together, even for merriment and diversion, but the conversation ends in a conspiracy against the public, or in some contrivance to raise prices.” With the government becoming a larger and larger influence on the economy, producers are finding it to be more in their interest to organize with the assistance of the legislature.
SEXUAL PRECOCITY CAUSED BY OVARIAN FOLLICULAR CYSTS: SPONTANEOUS REGRESSION AND RECURRENCE WITH PREPUBERTAL GONADOTROPIN LEVELS

Although small follicular ovarian cysts are common in asymptomatic prepubertal girls, larger ones may be associated with sexual precocity which can regress after cyst removal. We report 1 patient with recurrent functional ovarian cysts and another who had a presumptive single episode of cyst formation that regressed spontaneously. Patient 1 developed breasts at 3 years and vaginal bleeding at 4-10/12. Plasma estradiol (E2) was 180 pg/ml and LRF response was prepubertal (LH 0.4-0.8 ng/ml LER-960). E2 levels fell within 6 weeks to <10 pg/ml and remained low until 5-3/12 when bleeding recurred with E2 796 pg/ml. A 4×3 en ovarian follicular cyst with partial luteinization was removed from the left ovary. Cyst fluid contained 70,300 pg/ml E2; 21,600 pg/ml E1-Post-op the LRF test remained prepubertal when E2 was <10 pg/ml. At 5-5/12 E2 was 500 pg/ml and vaginal bleeding recurred. Treatment was begun with medroxyprogesterone acetate; during 20 months of therapy E2 has gradually fallen to <10 pg/ml and gonadotropin response to LRF remains prepubertal (LH 0.7-1.8 ng/ml). Patient 2 presented at 3-11/12 with breast development and E2 279 pg/ml. E2 fell to <10 pg/ml within 1 month and remained low for 2 years. At 6 years (BA 7-10/12) E2 was 13 pg/ml and the LRF test was pubertal. In sum 1) Markedly elevated E2 levels can occur in functional ovarian cysts as well as tumors. 2) Sporadic ovarian cyst formation may underlie some instances of premature thelarche or arrested sexual precocity.
Autophagy and Heart Failure: A Possible Role for Homocysteine

Autophagy is a process used for intracellular digestion of organelles and proteins and has special relevance to the long-lived cardiomyocytes in heart disease. The pathway for autophagy and all its mediators remain to be elucidated, but involve such proteins as Atg, Beclin-1, LAMP-2, BH3, Bcl2, PI3K Kinase as well as a plethora of others. It is still not entirely clear whether autophagy is destructive or beneficial to the cell; evidence suggests that the answer is case-specific. For instance, autophagy appears to preserve cell life under cases of ischemia in I/R injury, but is detrimental during reperfusion. High levels of homocysteine (Hcy), a sulfur-containing amino acid, have been shown to be an independent risk factor for chronic heart failure. There are several links to induction and repression of autophagy and Hcy; the following connections to Hcy and autophagy have been made: intracellular nitrous oxide production, intracellular calcium production, and reactive oxygen species production. Further work remains to be elucidated concerning the specific mechanisms under which autophagy occurs and possible Hcy-mediated connections. Moreover, the therapeutic implications might be of some promise to patients.
pH scales and proton-transfer reactions in saline media such as sea water

Abstract The three approaches to defining pH scales for use in sea water: the N.B.S. scale, the pH(SWS) or ‘total’ hydrogen ion concentration scale and the ‘free’ hydrogen ion concentration scale are described, and it is shown how these arise as a direct consequence of alternative experimental procedures for determining practical acidity constants. The advantages of conceptual simplicity and of experimental precision inherent in the use of concentration products to describe proton-transfer reactions in saline media are emphasised. In addition, the problems of theoretical interpretation and of reproducibility which result from the conventional nature of the N.B.S. pH scale are described, and the effect on the corresponding ‘apparent’ constants outlined. Insofar as it is concentration products rather than ‘apparent’ constants that are amenable to prediction using models for activity coefficients, the deliberate use of a ‘free’ hydrogen ion concentration scale should be applicable to many areas of aqueous geochemistry in addition to marine chemistry.
The metabolism of hydroxychlorpromazines by rat liver microsomes

Abstract The metabolism of a series of chlorpromazine derivatives was studied with a fortified preparation of rabbit liver microsomes. All of the monohydroxylated derivatives underwent mono-N-demethylation as the principal metabolic pathway. In addition, these hyaroxychlorpromazines were shown to undergo further hydroxylation to form ortho-dihydroxychlorpromazines, which were then mono-O-methylated. Thus, 7-hydroxychlorpromazine, a major metabolite of chlorpromazine, was apparently converted with this system to a mono-O-methylated 7,8-dihydroxychlorpromazine, which represents a new metabolic pathway.
READING REPLICATIONS: ROMAN RHETORIC AND GREEK QUOTATIONS

Adolf Furtwangler's concept of Roman copies and lost Greek originals has been largely dismantled in recent scholarship. Nevertheless, Romans created a sophisticated visual vocabulary which included direct quotations of Greek models, as well as allusions to styles associated with particular periods or individual Greek artists. The art-historical consciousness of Roman artists, patrons and visually literate viewers was not limited to the elite, but also pervaded works of private funerary art which often employed recognizably Greek compositions and body types for rhetorical effect in order to access abstract concepts of heroism, virtue and apotheosis. Ultimately, sculptural quotations and replications from the Greek are not symptomatic of a derivative and imitative artistic culture, but rather reveal a highly original and particularly Roman aesthetic of hybridity.
The Simultaneous Clustering of Point Defects during Irradiation

The simultaneous clustering of irradiation produced vacancies and interstitials in metals is investigated using the rate theory approach. Rate equations are used to describe the time-dependent concentrations of point defect clusters. Size-dependent bias factors and self-consistent reaction rate constants are used to evaluate the feed-back effects between the evolving vacancy cluster and interstitial loop populations. It is found that the concurrent presence of vacancy clusters depletes the free vacancy population and thereby reduces mutual point defect recombination. This has the effect of enhancing interstitial loop formation; increasing loop concentration, nucleation rate, average size, and growth speed of the average size. In 316 stainless steel, a diinterstitial binding energy of 1.19 eV results in a substantial decrease in loop concentrations at high temperatures, which is in qualitative agreement with experimental data. Es wird die gleichzeitige Clusterbildung von durch Strahlung erzeugten Leerstellen und Zwischengitterstorstellen mit der Methode der Ratengleichungen untersucht. Bilanzgleichungen werden benutzt, um die zeitabhangigen Konzentrationen der Punktdefektcluster zu beschreiben. Grosenabhangige Vorfaktoren und selbstkonsistente Reaktionskonstanten werden benutz, um die Ruckkopplungseffekte zwischen den sich entwickelnden Leerstellencluster und den Besetzungen der Interstitialschleifen zu berechnen. Es wird gefunden, das die konkurrierende Anwesenheit von Leerstellencluster die Besetzung freier Leerstellen verringert und dabei die gegenseitige Punktdefektrekombination verringert. Dies fuhrt zu einer Erhohung der Zwischengitterschleifenbildung und vergrosert die Schleifenkonzentration, Keimbildungsrate, mittlere Grose und die Wachstumsgeschwindigkeit der mittleren Ausdehnung. In rostfreiem 316-Stahl fuhrt eine Bindungsenergie von 1,19 eV der Di-Interstitials zu einer betrachtlichen Verringerung der Schleifenkonzentration bei hohen Temperaturen, die in qualitati er Ubereinstimmung mit experimentellen Ergebnissen ist.
Platelet-derived growth factor-BB-mediated activation of Akt suppresses smooth muscle-specific gene expression through inhibition of mitogen-activated protein kinase and redistribution of serum response factor.

Platelet-derived growth factor (PDGF) inhibits expression of smooth muscle (SM) genes in vascular smooth muscle cells and blocks induction by arginine vasopressin (AVP). We have previously demonstrated that suppression of SM-α-actin by PDGF-BB is mediated in part through a Ras-dependent pathway. This study examined the role of phosphatidylinositol 3-kinase (PI3K)y and its downstream effector, Akt, in regulating SM gene expression. PDGF caused a rapid sustained activation of Akt, whereas AVP caused only a small transient increase. PDGF selectively caused a sustained stimulation of p85/p110α PI3K. In contrast, p85/110β PI3K activity was not altered by either PDGF or AVP, whereas both agents caused a delayed activation of Class IB p101/110γ PI3K. Expression of a gain-of-function PI3K or myristoylated Akt (myr-Akt) mimicked the inhibitory effect of PDGF on SM-α-actin and SM22α expression. Pretreatment with LY 294002 reversed the inhibitory effect of PDGF. Expression of myr-Akt selectively inhibited AVP-induced activation of c-Jun N-terminal kinase and p38 mitogen-activated protein kinases, which we have shown are critical for induction of these genes. Nuclear extracts from PDGF-stimulated or myr-Akt expressing cells showed reduced serum response factor binding to SM-specific CArG elements. This was associated with appearance of serum response factor in the cytoplasm. These data indicate that activation of p85/p110α/Akt mediates suppression of SM gene expression by PDGF.
Evidence for GABAB-mediated mechanisms in experimental generalized absence seizures.

Experimental absence seizures are characterized by the fact that they are exacerbated by both direct and indirect GABA agonists. To date most of the studies that have examined this phenomenon have utilized GABAA agonists. We assessed the effect of a GABAB agonist, baclofen and a specific GABAB antagonist in two pharmacologic models of absence seizures in rodent after using either γ-hydroxybutyrate or pentylenetetrazole to induce the bilaterally synchronous spike wave discharges that typify absence seizures in rodent. Baclofen markedly prolonged and the GABAB antagonist attenuated or blocked the experimental absence seizures in both models. These data suggest a role for GABAB-related mechanisms in the pathogenesis of generalized absence seizures and raise the possibility that GABAB antagonists may have therapeutic potential as antiabsence drugs.
Obstacles to the flow of requirements verification

The process of developing technical requirements and subsequently documenting adherence to those requirements is a primary task for Systems Engineering. Disciplined validation and verification of requirements helps assure that the product system will be successful as designed and gives the program a fighting chance to achieve its goals. But commitment and adherence to a process of thorough validation and verification is not always sufficient. Unforeseen technical constraints and logical inconsistencies often spring up at the last minute to block requirements verification for complex systems. By recognizing weaknesses in the structure and definition of requirements that are likely to interfere with the verification flow, the systems engineer can create a more manageable hierarchy of requirements and more effectively redirect the verification process when difficulties arise. © 2008 Wiley Periodicals, Inc. Syst Eng
Mathematical model of an air-to-air heat pump equipped with a capillary tube

Abstract This paper described in general a computer model for simulation of steady-state performance of a split, residential, air-to-air heat pump. Organization of the model is discussed and approach to modelling of main heat pump components is explained. The modelling effort emphasis was on the local phenomena to be described by fundamental thermodynamic, heat transfer and fluid mechanic relationships. The model has been verified in a wide range of operating conditions from high temperature cooling to low temperature heating.
AN URBAN SCHOOLS–UNIVERSITY PARTNERSHIP THAT PREPARES AND RETAINS QUALITY TEACHERS FOR “HIGH NEED” SCHOOLS

This article describes a full-time teaching internship program, where, in lieu of student teaching, interns serve as classroom teachers in urban area schools. Through a partnership between a university and participating school districts, all interns received intensive mentoring and induction during their first year. Among the program results, were a 100% retention rate of interns in the teaching profession, significant growth in teaching interns' confidence, readiness, and self-efficacy regarding their abilities to teach successfully. In addition, school administrators consistently rated interns as proficient teachers using a state-approved evaluation instrument. Implications for continuing the internship program are presented.
Methotrexate and erythro-9-(2-hydroxynon-3-yl) adenine therapy for rat adjuvant arthritis and the effect of methotrexate on in vivo purine metabolism

Abstract The objectives were: (1) to test the association of methotrexate (MTX) efficacy in rat adjuvant arthritis (rat AA) with interference of purine biosynthesis and adenosine metabolism and (2) to test the efficacy of erythro-9-(2-hydroxynon-3-yl) adenine (EHNA), an inhibitor of adenosine deaminase, and the efficacy of aminoimidazolecarboxamide (AICA) riboside plus MTX in rat AA. Radiographic and histologic examinations of the hind limbs were measures of efficacy. Urinary excretions of AICA and adenosine were makers of AICA ribotide transformylase inhibition (i.e., blockage of purine biosynthesis) and interference with adenosine metabolism, respectively. AICA and adenosine excretions increased during the day of MTX dosing (treatment day) compared to the previous baseline day in animals responding well to MTX (i.e., low radiographic and histologic scores). Based on radiographic and histologic scores, adjuvant injected rats were separated into two disease categories (i.e., no/mild and moderate/severe). Only AICA excretion was significantly elevated on the treatment day in rat AA with no/mild disease (i.e., those responding well to MTX therapy). AICA (not adenosine) excretion was significantly correlated with the above scores. EHNA was not efficacious, even at toxic levels, while AICA riboside potentiated the efficacy of MTX. The data suggests that efficacious MTX therapy in rat AA (1) blocks purine biosynthesis; (2) increases in in vivo AICA levels. Also adenosine accumulation and blockage of adenosine deaminase (i.e., by EHNA) appear to be less critical to MTX efficacy. Increased levels of AICA metabolites may suppress the immune response in rat AA.
Angular distributions in the photoelectron spectroscopy of SF6

Abstract The photoelectron angular distributions of SF 6 have been obtained using 584 A light. The assignments of the photoelectron bands to the corresponding orbitals are based on the trends in the asymmetry parameters β and other theoretical and experimental data.
In vivo and in vitro response of corpus cavernosum to phosphodiesterase-5 inhibition in the hypercholesterolaemic rabbit.

OBJECTIVE To investigate the effects of hypercholesterolaemia (HC) on rabbit corpus cavernosa in vivo and in vitro, and evaluate the efficacy of vardenafil and sildenafil in normal and HC rabbits, as the phosphodiesterase-5 (PDE-5) inhibitors vardenafil and sildenafil are widely used for treating erectile dysfunction (ED) and most organic causes of ED are associated with vascular risk factors like HC. MATERIALS AND METHODS Male New Zealand White rabbits were randomly divided into two groups; 11 HC rabbits were fed a 2% cholesterol diet, and 12 age-matched control rabbits received a regular diet. After 12-14 weeks, erectile responses to intravenous sodium nitroprusside (SNP) and PDE-5 inhibitors were evaluated for 2 h in conscious rabbits. Penile length was measured and the area under the curve calculated. Relaxant responses of corpus cavernosal strips to electrical-field stimulation (EFS) were measured before and after exposure to PDE-5 inhibitors and the nitric oxide synthase inhibitor N'-nitro-L-arginine methyl ester. RESULTS HC rabbits had a lower erectile response to SNP than controls; in both control and HC rabbits there was a greater erectile response after simultaneous exposure to SNP and vardenafil, or SNP and sildenafil. However, the responses of the HC rabbits were still significantly less than those of the controls. Corpora from control rabbits responded to EFS with greater relaxations at all frequencies, except 1 Hz. Corpora from both HC and control rabbits had greater responses to EFS after exposure to vardenafil and sildenafil; N'-nitro-L-arginine methyl ester diminished the response to EFS. CONCLUSIONS There was a significantly lower in vivo and in vitro erectile response in HC rabbits than in controls; erectile function measured in conscious rabbits can be used to assess quantitatively the efficacy of different agents, e.g. sildenafil and vardenafil, in pathological animals. In addition, both agents improve in vitro responses of erectile tissue from HC rabbits to EFS.
The DG/VMS Method for Unified Turbulence Simulation

The high cost of wind tunnel testing and the ongoing reduction in national wind tunnel facilities are forcing the aerospace engineering community to increasingly rely on computational fluid dynamics (CFD) to predict the performance of new aircraft designs. However, most aerospace applications are characterized by flows that exhibit large-scale unsteady turbulence and the accurate prediction of these flows is often critical to predicting overall performance. Unfortunately, the turbulence modeling approaches used in existing industrial CFD simulation tools often do not accurately predict large-scale turbulent flows which limits their utility. This paper introduces a new paradigm, called the DG/VMS method, for CFD that is specifically designed to accurately and efficiently predict complex flows dominated by large-scale turbulence. Here, the DG/VMS formulation is presented along with results for several laminar validation tests. Our future work will apply the DG/VMS to turbulent flows.
Neurodevelopmental outcome of children with evidence of periventricular leukomalacia on late MRI

Abstract Fifteen children, 8 months of age or older, from a neonatal follow-up program underwent magnetic resonance imaging and neurologic, cognitive, and language evaluations. Magnetic resonance imaging findings in all children included increased white matter signal on T 2 -weighted images and ventricular enlargement adjacent to regions of abnormal white matter. The extent and degree of abnormal white matter signal and the degree of sulcal prominence were variable. Twelve children had cerebral palsy; 5 children, 4 of whom had cerebral palsy, manifested significant sensory impairments. The median score on cognitive testing was 89; only 2 children exhibited severe-to-profound cognitive disability. Cognitive scores were stable on retesting. The degree of motor disability was correlated with the extent of white matter signal abnormality; however, cognitive outcome was not related to the extent and degree of white matter signal abnormality or to the degree of sulcal prominence. Despite the association of a major handicapping condition and periventricular leukomalacia, cognitive and language functioning may be relatively spared.
Changes in the orbital periods of close binary stars

A number of close binary stars show erratic changes in their orbital periods on time scales of order 5-10 yr. Recently it has been proposed that the period changes are the result of changes in the quadrupole moment of one star, caused in turn by an alteration of the internal structure of that star. Magnetic pressure, which either distorts the shape of the star or changes its tidally induced quadrupole moment, is suggested as the driving force behind the alteration. Here, the amount of energy required to distort one component of a binary and match the observed period changes is estimated. The rate at which energy is produced or lost is governed by the thermal time scale of the star, and the estimates indicate that the observed period changes would take at least 1000 yr for the tidal quadrupole mechanism, and of order 60 yr to match a period change in V471 Tau which took only 4 yr.
The magnetic moment of the electron

Abstract The spin magnetic dipole moment of the electron is computed to fourth order in perturbation theory. The procedure is to consider a system of one electron moving in a constant external magnetic field. The Green's function and mass operator for the electron are computed as functions of this field. The expectation value of the mass operator is the self-energy of the electron and the magnetic moment is identified from that part of the self-energy linear in the external field. The techniques used are illustrated in a calculation of the second-order moment. The derivation of the fourth-order moment is sketched. It is found to be μ(4) = −0.328 ( (α π) 2 in Bohr magnetons, where α is the fine-structure constant. This differs from the result of a previous calculation.
An efficient method to calculate resonance Raman amplitudes via polynomial propagation

Abstract An accurate and efficient method is suggested for calculating the resonance Raman spectrum. This approach, based on Chebyshev propagation, bears close resemblance to the time-dependent theory of resonance Raman scattering due to Heller and co-workers [S.-Y. Lee, E.J. Heller, J. Chem. Phys. 71 (1979) 4777; D.J. Tannor, E.J. Heller, J. Chem. Phys. 77 (1982) 202; E.J. Heller, R.L. Sundberg, D.J. Tannor, J. Phys. Chem. 86 (1982) 1822]. However, it makes no reference to time and requires no approximation of the propagator. Since Raman amplitudes can be expressed in this method as a discrete Fourier transform of cross-correlation functions, no integration error is introduced. In addition, the propagation of the excited-state wave packet can be restricted to real space, further reducing computational costs. Numerical testing of the method is carried out with a two-dimensional methyl iodide model.
Facilitation of dopamine release in vivo by serotonin agonists: studies with microdialysis.

Using microdialysis, changes in extraneuronal levels of dopamine (DA), and the metabolites of DA and serotonin (5-HT), were monitored concurrent with perfusion of 5-HT1 agonists into the anterior striata of anesthetized rats. Perfusion of 5-HT facilitated DA release in a dose dependent manner, and to a greater extent than any other agonist tested. Extraneuronal DA levels increased 34% with perfusion of 0.04 nmol 5-HT and 18-fold with perfusion of 4.0 nmol 5-HT. Perfusion with multiple doses of either 1-(m-chlorophenyl)piperazine (m-CPP) or trifluoromethylphenylpiperazine (TFMPP) also resulted in a dose-dependent facilitation of DA release with a 40% increase in extracellular DA produced by either 0.4 nmol m-CPP or 10.0 nmol TFMPP. A 50-fold increase in DA followed 40.0 nmol m-CPP, while 160 nmol TFMPP enhanced DA 11-fold. Local application of either 5-methoxy-3(l,2,3,6-tetrahydro-4-pyridinyl)-lH indole succinate (RU24969) or 8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT) (2.0 nmol perfused over 20 min) increased extracellular DA by 300 and 40%, respectively. RU24969 (2.0 nmol) also facilitated DA release following systemic pretreatment with 8-OH-DPAT (100 μg/kg). Perfusion with fenfluramine to release endogenous 5-HT also increased extraneuronal DA in a dose-dependent manner, and this facilitation was prevented by pretreatment with the 5-HT reuptake inhibitor fluoxetine. The facilitation of DA release by 0.4 nmol 5-HT was reduced by pretreatment with the 5-HT1 antagonist pindolol (4.0 nmol). These results suggest that serotonergic innervation of the anterior striatum may exert a facilatory influence on DA release.
Morphological analysis of surface immunoglobulin biosynthesis in mouse B lymphoid cells using immunoelectron microscopy.

Abstract Immunoelectron microscopic techniques were employed to investigate the biosynthesis of surface immunoglobulin (sIg) molecules in murine splenic B lymphocytes. In addition, cryoultramicrotomy was used due to its unique ability to retain antigenicity and provide good accessibility of external immunolabeling reagents to the cellular interior. In order to induce the biosynthesis of sIg, preexisting surface molecules were first removed completely by treatment with antibody and chymotrypsin. And the cells were then allowed to regenerate the expression of sIg molecules in culture. Our results clearly indicate that cytoplasmic immunoglobulin (cIg) exists in a close association with endoplasmic reticulum, Golgi, and vesicle structures within the cytoplasm as early as 15–30 min after antibody/enzyme treatment. After approximately 60 min, intracellular cIg molecules were observed to be incorporated into the plasma membrane through the fusion of cIg containing vesicles with the surface membrane. Reexpression of sIg reaches about 50% of its original level at 6 hr and 90% of its original level at 20 hr of incubation. Both the intracellular appearance of Ig-positive structures and reexpression of sIg on the cell surface are found to be inhibited by both puromycin and tunicamycin which suggest that both protein synthesis and glycosylation are required for sIg synthesis and reexpression. To our knowledge these studies have provided the first morphological analysis of the biosynthesis of membrane glycoproteins with intact whole cells.
Review of LCA methods for ICT products and the impact of high purity and high cost materials

This paper expands upon previously published work aimed at more fully assessing the lifecycle impacts of semiconductor manufacturing and product use. Specific focus is placed on energy and CO 2 impacts associated with bringing materials to the high purity grade required for semiconductor manufacturing.
A deterministic computational model for the two dimensional electron and photon transport

A deterministic (non-statistical) two dimensional (2D) computational model describing the transport of electron and photon typical of space radiation environment in various shield media is described. The 2D formalism is casted into a code which is an extension of a previously developed one dimensional (1D) deterministic electron and photon transport code. The goal of both 1D and 2D codes is to satisfy engineering design applications (i.e. rapid analysis) while maintaining an accurate physics based representation of electron and photon transport in space environment. Both 1D and 2D transport codes have utilized established theoretical representations to describe the relevant collisional and radiative interactions and transport processes. In the 2D version, the shield material specifications are made more general as having the pertinent cross sections. In the 2D model, the specification of the computational field is in terms of a distance of traverse z along an axial direction as well as a variable distribution of deflection (i.e. polar) angles θ where −π/2<θ<π/2, and corresponding symmetry is assumed for the range of azimuth angles (0<φ<2π). In the transport formalism, a combined mean-free-path and average trajectory approach is used. For candidate shielding materials, using the trapped electron radiation environments at low Earth orbit (LEO), geosynchronous orbit (GEO) and Jupiter moon Europa, verification of the 2D formalism vs. 1D and an existing Monte Carlo code are presented.
Digital approximation by point-by-point state matching with higher-order holds†

This paper considers the problem of approximating a continuous-data system by a sampled-data model. The approximation is achieved by comparison of the states of the systems at each sampling period, It is shown that it is possible to match all the states if a hold device of sufficiently high order is utilized after the sampler. The order of the hold device necessary depends on the ratio of the number of states and the number of controls of the system. An example is presented to illustrate the procedure. The method is useful when an existing analogue system is to be converted into a digital system with minimal changes in performance.
Spin-torque ac impedance in magnetic tunnel junctions

Subjecting a magnetic tunnel junction (MTJ) to a spin-transfer torque and/or electric voltage-induced magnetic anisotropy induces magnetic precession, which can reciprocally pump current through the circuit. This results in an ac impedance, which is sensitive to the magnetic field applied to the MTJ. Measurement of this impedance can be used to characterize the nature of the coupling between the magnetic free layer and the electric input as well as a readout of the magnetic configuration of the MTJ.
Development of a new finite element formulation for the elasto-plastic analysis of fiber-reinforced composites

Abstract An analysis model is presented for the elasto-plastic analysis of continuous fiber-reinforced composite structures. The model uses the material properties of each constituent separately instead of the smeared global properties obtained from the lamination theory. Both fiber and matrix stresses are computed using the analysis model. Thus, the elasto-plastic deformation of a metal-matrix composite, composed of elastic fibers and elasto-plastic matrix, can be analyzed using the yield function and the flow rule suitable for each constituent. If each constituent is homogeneous and isotropic, then the usual von Mises yield function and the Prandtl-Reuss flow rule can be used. There is no need to obtain the global elasto-plastic material properties using the rule of mixtures. The formulation for the finite element matrix equation is given for the analysis model. Some numerical examples are solved using the method.