cssi/SciSciGPT-SciSciNet huggingface dataset:
Laser performance operations model (LPOM): a tool to automate the setup and diagnosis of the National Ignition Facility

The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory (LLNL) is a stadium-sized facility containing a 192-beam, 1.8 MJ, 500-TW, 351-nm laser system together with a 10-m diameter target chamber with room for nearly 100 experimental diagnostics. When completed, NIF will be the world's largest laser experimental system, providing a national center to study inertial confinement fusion and the physics of matter at extreme energy densities and pressures. The first four beamlines (a quad) have recently been commissioned, and operations on the first bundle (units of eight beamlines) will begin in Summer 2005. A computational system, the Laser Performance Operations Model (LPOM) has been developed and deployed to automate the laser setup process, and accurately predict laser energetics. For each shot on NIF, the LPOM determines the characteristics of the injection laser system required to achieve the desired main laser output, provides parameter checking for equipment protection, determines the required diagnostic setup, and supplies post-shot data analysis and reporting.
Vacuum Process Evaluation

Vacuum process evaluation is a new technique to (1) Determine the outgassing occurring within a vacuum system as a continuous function of time, and (2) Analyze the resulting curve to obtain information as to the source and nature of the outgassing. The report describes this technique and its application in determining the optimum combination of such parameters as temperature, time, materials, restrictions, and pumps on such processes as hermetic volume exhaust and cellulose dehydration. Vacuum process evaluation has also been used to study such phenomena as the outgassing characteristics of insulating materials and vacuum gages, the flow of gases through orifices and short tubes, and the gettering action of various materials. A digital computer and data reduction facilities have been incorporated to eliminate the detailed hand calculations and plotting. This has resulted in a rapid and inexpensive method for the study of vacuum engineering problems.
USING SCORE EQUITY ASSESSMENT TO EVALUATE THE EQUATABILITY OF THE HARDEST HALF OF A TEST TO THE TOTAL TEST

In an article published in the spring 2003 issue of Harvard Educational Review, Roy Freedle stated that the SAT® is both culturally and statistically biased. Freedle proposed a solution to this bias, which involved using a half-test made up of the most difficult items culled from complete SAT examination. His claims, which garnered national attention, were based on serious errors in his analysis. In Dorans and Zeller (2004), we demonstrated that the effects Freedle reported are reduced substantially when the data are analyzed correctly. Here, we describe a sound way of assessing whether the current SAT scoring procedure is fair, and we examine what happens when we subject the Freedle's hard half-test to a score-equity assessment.
Purification to Apparent Homogeneity and Properties of Pig Kidneyl-Fucose Kinase

Abstract l-Fucokinase was purified to apparent homogeneity from pig kidney cytosol. The molecular mass of the enzyme on a gel filtration column was 440 kDa, whereas on SDS gels a single protein band of 110 kDa was observed. This 110-kDa protein was labeled in a concentration-dependent manner by azido-[32P]ATP, and labeling was inhibited by cold ATP. The 110-kDa protein was subjected to endo-Lys-C digestion, and several peptides were sequenced. These showed very little similarity to other known protein sequences. The enzyme phosphorylated l-fucose using ATP to form β-l-fucose-1-P. Of many sugars tested, the only other sugar phosphorylated by the purified enzyme wasd-arabinose, at about 10% the rate ofl-fucose. Many of the properties of the enzyme were determined and are described in this paper. This enzyme is part of a salvage pathway for reutilization of l-fucose and is also a valuable biochemical tool to prepare activated l-fucose derivatives for fucosylation reactions.
Botulinum Toxin for the Treatment of Sialorrhea: A Meta-analysis

ObjectivesBotulinum toxin has emerged as an effective approach for the management of sialorrhea. This study presents a critical literature review and meta-analysis to determine the impact of botulinum toxin on drooling severity in patients with sialorrhea.Data SourcesOvid MEDLINE and the Cochrane databases.Review MethodsThe above sources were searched to identify studies examining botulinum toxin for the treatment of sialorrhea. Included studies were randomized, placebo-controlled trials. Excluded studies failed to report quantifiable outcome measures of drooling severity at 4 weeks postintervention.ResultsEight studies involving 181 patients (83 placebo; 98 active) were included in the analysis. Botulinum toxin was found to significantly decrease the severity of drooling in patients with sialorrhea (standardized mean difference [SMD], −1.54; 95% confidence interval [CI], −2.05 to −1.04; P = .06; I2 = 48%) when compared with placebo control using random effects models. The effect was significant in both a...
The inhibition of chick embryo cell growth by medium obtained from cultures of Rous sarcoma cells

Abstract Rous sarcoma cells even in large numbers grow poorly when spread on the surface of a tissue culture dish unless normal cells are present in the majority. The Rous sarcoma cells can however grow to a much greater extent than normal cells when suspended in soft agar. Conditioned medium obtained from normal cells can support the growth of Rous sarcoma cells. For the first few days after infection the cells continue to release a substance as they had before infection, which enhances the growth of small numbers of normal chick embryo cells. When the infected cells undergo transformation however, they release a substance which, at high concentrations, inhibits the growth of small numbers of normal cells. They also continue to produce the growth enhancing substance, but its presence can only be detected when the effect of the inhibitory material is removed by dilution.
Modular Structure in Developmentally Eliminated DNA in Tetrahymena may be a Consequence of Frequent Insertions and Deletions

The work reported here describes insertion-deletion (Indel) polymorphisms in two internally eliminated sequences (IESs, that are deleted during development in Tetrahymena): a 1.8 kb Indel at one end of the 1.1 kb H1 IES and a 0.5 kb Indel inside the 1.4 kb calmodulin (C) IES. These two IESs are located in the proximity of the H1 histone and calmodulin genes, respectively, and are among the ten IESs that have been fully sequenced out of an estimated total of 6000. Three hundred base-pairs of the 1.8 kb H1 Indel are retained in the macronucleus. Both the +Indel and the -Indel variants of the H1 and C IESs that occur in different strains are eliminated during development. Thus, a drastic change involving over half of the deleted sequence and 300 bp of flanking sequence does not disable developmental elimination of the H1 IES, which may indicate a lack of requirement for specific sequences on the Indel side of the IES. The H1 Indel is a composite of three sequence elements: a unique segment and two other sections containing members of different repeat families. One of these, a 0.5 kb repetitive component, is 75% similar to another 0.5 kb sequence that constitutes the C Indel, a sequence present in the middle of the calmodulin IES in some strains, but not in others. Therefore, the C Indel sequence is likely to have been part of a mobile unit, even though it has no obvious features of a transposon. However, sequences similar to the C Indel are present in about 100 copies in the genome. The results suggest that IESs may consist, at least in part, of relatively short modules of repeated sequences that are the source of insertion-deletion polymorphisms among strains of Tetrahymena thermophila.
Effect of molecular symmetry on melting temperature and solubility

Molecular symmetry has a pronounced effect on the melting properties and solubility of organic compounds. As a general rule, symmetrical molecules in crystalline form have higher melting temperatures and exhibit lower solubilities compared with molecules of similar structure but with lower symmetry. Symmetry in a molecule imparts a positive amount of residual entropy in the solid phase (i.e., more possible arrangements leading to the same structure). This means that the entropy of a crystal of symmetric molecules is greater than the entropy of crystal of a similar, but non-symmetric molecule. An analysis is presented relating the enthalpy, entropy and temperature of melting for an idealised system of structural isomers of different molecular symmetries. The analysis presented helps explain why often, yet not always, the crystal of a more symmetric molecule, which has greater entropy to start (closer to that of the liquid), also exhibits a greater gain in entropy upon melting, compared with the crystal of a less symmetrical molecule. The residual entropy due to molecular symmetry has the direct effect of reducing the entropy gain upon melting (a negative effect). However, molecular symmetry also exerts indirect effects on both the entropy and enthalpy of melting. These indirect effects, imposed by the condition of equilibrium melting, are positive, such that it is the balance between the direct and indirect effects what determines the value observed for the entropy of melting of the symmetric molecules. When the indirect effect of molecular symmetry is greater than its direct effect, the observed entropy gain upon melting of the more symmetrical molecule is greater than that of a less symmetrical one.
Flexible manufacturing systems: a primer on enhancing productivity while controlling cost

Discusses flexible manufacturing systems (FMS) and measures the benefits of substituting production flexibility for inventory. Compares the trade‐offs that arise in balanced operations, graphical models and some of the associated risks of flexible manufacturing implementation, operation and management. Also addresses the question of selecting flexibility over other techniques as well as benefits which flexibility provides. Examines a brief comparison between traditional and flexible manufacturing. Examples include illustrations of the benefits of FMS and cost flexibility, plus a view of the future role of FMS.
Changes in the Phytochemical Composition and Profile of Raw, Boiled, and Roasted Peanuts

Peanuts are consumed mostly as processed products. Although the effect of processing on isoflavone composition of legumes has been extensively studied, there has been no such study on peanuts. The objective of this study was to evaluate the effect of processing (boiling, oil- and dry-roasting) on the phytochemical composition of peanuts. Boiling had a significant effect on the phytochemical composition of peanuts compared to oil- and dry-roasting. Boiled peanuts had the highest total flavonoid and polyphenol content. The biochanin A and genistein content of boiled peanut extracts were two- and fourfold higher, respectively. trans-Resveratrol was detected only in the boiled peanuts, with the commercial product having a significantly (p ≤ 0.05) higher concentration. Ultraviolet and mass spectrometry chromatograms for the boiled peanut extracts show the presence of four additional peaks that were not observed in the raw peanut extracts.
Dynamic Headspace Analyses of Volatile Compounds of Cheddar and Swiss Cheese during Ripening

The volatile compounds of Cheddar and Swiss cheeses during ripening for 9 wks at 11 o C and 21 o C, respectively, were analyzed by a dynamic headspace analyzer/gas chromatograph every week. The compounds were identified by a combination of retention times and mass spectra. The volatile compounds of Cheddar increased 5.6 and Swiss cheese 15 times as ripening increased from 0 to 9 wks. The amount of volatile compounds of Swiss cheese was 2.6 times greater than that of Cheddar cheese during ripening. The volatile compounds were ketones, alcohols, aldehydes, esters, acids, sulfur compounds, benzenes, and hydrocarbons. Ketones and alcohols accounted for 92% of volatiles from Cheddar cheese and 88% of those from Swiss cheese
Evaluating the Effect of Image Preprocessing on an Information-Theoretic CAD System in Mammography

Rationale and Objectives In our earlier studies, we reported an evidence-based computer-assisted decision (CAD) system for location-specific interrogation of mammograms. A content-based image retrieval framework with information theoretic (IT) similarity measures serves as the foundation for this system. Specifically, the normalized mutual information (NMI) was shown to be the most effective similarity measure for reduction of false-positive marks generated by other prescreening mass detection schemes. The objective of this work was to investigate the importance of image filtering as a possible preprocessing step in our IT-CAD system. Materials and Methods Different filters were applied, each one aiming to compensate for known limitations of the NMI similarity measure. The study was based on a region-of-interest database that included true masses and false-positive regions from digitized mammograms. Results Receiver-operating characteristics (ROC) analysis showed that IT-CAD is affected slightly by image filtering. Modest, yet statistically significant, performance gain was observed with median filtering (overall ROC area index A z improved from 0.78 to 0.82). However, Gabor filtering improved performance for the high-sensitivity portion of the ROC curve where a typical false-positive reduction scheme should operate (partial ROC area index 0.90 A z improved from 0.33 to 0.37). Fusion of IT-CAD decisions from different filtering schemes markedly improved performance (A z = 0.90 and 0.90 A z = 0.55). At 95% sensitivity, the system's specificity improved by 36.6%. Conclusions Additional improvement in false-positive reduction can be achieved by incorporating image filtering as a preprocessing step in our IT-CAD system.
Changing indications for penetrating keratoplasty in Southern California, 1994–1998

Over the 50 years, penetrating keratoplasty (PKP) has progressed from a rare procedure with marginal success to one of the most common and most successful tissue transplants. We review the changing indications for PKP between 1994 and 1998. In decreasing order, the six most common indications were: pseudophakic corneal edema, regraft, unspecified scar, unspecified ulcer, keratoconus, and Fuchs endothelial dystrophy.
Micromodel Study of Surfactant Foam Remediation of Residual Trichloroethylene

A remediation technique involving surfactant foam (SF) was investigated by using a micromodel with a view toward improved contaminant displacement. A residual trichloroethylene (TCE) saturation was emplaced in an otherwise water-saturated micromodel. Air flow was introduced to a surfactant solution flow (Sodium C14-16 olefin sulfonate 2%(w)) commonly utilized in surfactant flushing to obtain the SF. Conventional remediation strategies, surfactant flushing, water flooding, and gas flooding were also employed for comparison to the SF flooding. The removal efficiency was quantified by directly measuring the remaining TCE blob area with an image analyzer. The micromodel visualization showed that the SF is capable of displacing a higher amount of TCE as compared to surfactant solution alone. The SF flooding removed 99% of the residual TCE, while surfactant flushing removed 41% with 25 pore volumes of the same surfactant solution. Based on micromodel visualization, the resulting enhanced removal of TCE blobs du...
Diffusion on a self-assembled monolayer: molecular modeling of a bound + mobile lubricant.

The diffusion of tricresyl phosphate molecules on an octadecyltrichlorosilane self-assembled monolayer (SAM) was characterized using molecular dynamics simulations. The simulations predict that when placed on the top of a close-packed SAM, the molecules remain mobile on the surface with an isotropic diffusion activation energy of ∼9 kJ/mol. In contrast, an anisotropic barrier that results from chain tilt within the SAM is predicted for diffusion into a defect created by reducing the alkane chain length within a cylinderical region of the surface. Once in the defect, the molecules become trapped by embedding part of the molecule into the side of the SAM.
Cloning and Characterization of Human TAF20/15 MULTIPLE INTERACTIONS SUGGEST A CENTRAL ROLE IN TFIID COMPLEX FORMATION

TFIID is a multiprotein complex that plays a central role in the initiation and regulation of class II transcription. Transcription factor IID (TFIID) nucleates transcription initiation complex formation by direct core promoter binding and mediates the action of transcriptional activators, in part via direct interactions with them. Molecular studies of the TFIID complex have identified multiple subunits whose potential interactions can be recapitulated in vitro with recombinant polypeptides. Here we report the cloning of human TATA box binding protein (TBP)-associated factor 20 (TAF20) and the consequent identification of an additional, related TFIID subunit, human TAF15 (hTAF15). Multiple TAF20/15 interactions have been detected within native TFIID preparations and further analyzed with recombinant subunits. Along with the demonstration of a high affinity association between TAF20/15 and TBP, the present results suggest that hTAF20/15 may complement hTAF250 in directing the association of TAFs with TBP to form a TFIID complex. Finally, we present detailed mutagenesis studies that reveal multiple, distinct interaction surfaces on the presumed globular domain of hTAF20/15 and may be used, in conjunction with structural data, to model the architecture of the TFIID multiprotein complex.
An evidence-based approach to treating otitis media

More than 20 years ago, a shrewd clinician remarked, "There is little evidence that those antimicrobial agents which hypothetically or in vitro are more effective ... are superior in the treatment of otitis when compared to penicillin alone." Several hundred clinical trials later, the advantages of broad spectrum drugs remain unproved, and questions remains as to whether antibiotics are required for most episodes of AOM. Further, antibiotics have been demoted to the status of optional therapy for OME. This situation is unlikely to change as new studies with new antibiotics proliferate. What is clear, however, is that accelerated patterns of bacterial resistance mandate an evidence-based approach to managing otitis media. Bacteria have an uncanny ability to learn new mechanisms of antibiotic resistance. A large part of bacterial "education" has undoubtedly been fueled by antibiotic prescriptions from well-intentioned physicians, with unrealistic expectations of drug efficacy. A judicious approach to antibiotic treatment of otitis media can result only from knowing the spontaneous course of the disorder and incremental effect of antibiotics on clinical outcomes. In this article, a series of unifying concepts are developed to help practicing clinicians with an evidence-based approach to managing otitis media. Critical review of the published evidence suggests that the most favorable outcomes from medical treatment will occur if practitioners: appreciate the favorable natural history of untreated otitis media realize that OME may take months to resolve following a single AOM episode modify risk factors to improve the odds of spontaneous resolution use pneumatic otoscopy and confirmatory tympanometry to diagnose OME recognize the limited impact of antibiotic therapy on treatment and prevention balance the benefits of antibiotics against the risk of accelerated bacterial resistance avoid repetitive, prolonged, or prophylactic antibiotic treatment of chronic OME avoid ineffective therapy, such as antihistamine/decongestant preparations An important aspect of management is helping caregivers understand the natural history of otitis media and the impact of medical treatment on shortterm and long-term outcomes. Realistic expectations on the part of all involved parties should facilitate rational decisions about watchful waiting, medical therapy, and the need for surgical intervention.
Interaction of absences and grades in a college course.

Summary The validity of four causal models of the relationship between absences and grades was tested in 496 undergraduate psychology students. As predicted, absences were negatively correlated with grades; the results are consistent with two causal models of this relationship. Absence from class appeared to cause lower grades but low grades also appeared to cause more frequent absences from class. These findings were interpreted as suggesting that absences and grades can interact to produce a spiral of declining academic achievement in some students.
Variable effects of symbiotic snapping shrimps on their sponge hosts

Mutualistic relationships are ubiquitous in tropical coral reefs, but the costs and benefits to partner species are often poorly known. In Caribbean coral reefs, several species of snapping shrimp (Synalpheus spp.) dwell exclusively in marine sponges, which serve as both habitat and food source. A paired experimental design was used to examine the effects of Synalpheus occupancy on predation, morphology, and growth of their sponge host Lissodendoryx colombiensis in Bocas del Toro, Panama (9.351°N, 82.258°W) in June 2009. Shrimp occupancy significantly decreased consumption of sponges by a predatory sea star (Oreaster reticulatus) and also affected sponge morphology; sponges grown without shrimps decreased in canal size, in both the laboratory and the field. Shrimp occupancy had more ambiguous effects on sponge growth. In laboratory experiments, shrimp occupancy benefited sponge growth, although all sponges experienced overall decreases in mass. In field experiments, there were no significant differences in growth between occupied and empty sponges. However, the benefits of shrimp occupancy on sponge growth were negatively correlated with overall increases in sponge size; sponges that decreased in mass during the experiment benefited more from shrimp occupancy than sponges that increased in mass. These costs and benefits suggest that Synalpheus has variable effects on sponges: positive effects on sponges in the presence of predators, and/or when sponges are decreasing in mass (e.g., during periods of physical stress), but a negative effect on sponges during periods of active sponge growth.
An Overview of QA/QC Requirements in Present NPP Projects

The paper analyses the Quality Assurance/Quality Control requirements imposed by various regulations concerning actual NPP projects and discusses the status of different codes in front of such provisions. Taking the example of several countries, the paper starts with a general view on regulations applicable to conventional pressure equipment, and covers in a second stage nuclear pressure equipment. It identifies for manufacturer and third parties, the right QA/QC questioning, before to begin any new nuclear pressure equipment project.Copyright © 2009 by ASME
Thermal osmosis near a buried heat source

Abstract Phenomenological equations for fluxes of heat and volume and balance equations for mass, temperature and pressure are stated for a water-saturated porous medium near a heat source. Previous work is discussed, and the behavior of the system is examined, in the light of the correct governing equations.
Serum chromogranin A: Early detection of hormonal resistance in prostate cancer patients

We monitored both chromogranin A (CgA) and neuron specific enolase (NSE) in serial serum specimens from 14 patients with prostate cancer (CAP patients) showing resistance to hormonal treatment. Elevated serum CgA was detected in 10 out of these 14 patients (71%) during treatment, and an early appearance of elevated serum CgA was found in 6 of 14 (43%) of these patients when serum tPSA levels were still in the normal range. If patients with radical prostatectomy were not included, the percentage of patients showing an early appearance of elevated serum CgA would have been much higher. Elevated serum CgA levels also were found in patients not subject to hormonal therapy. Serial specimens from two out of three prostate cancer patients, randomly selected, contained elevated serum CgA. Serum NSE was not detectable in any of the serial specimens we studied, suggesting that CgA, not NSE, should be used as a marker for neuroendocrine differentiation. We also compared the serum CgA in random serum specimens between patients with BPH (benign prostate hyperplasia) and with prostate cancer in the concentration range of serum tPSA between 3–15 ng/mL. Although serum CgA concentrations in BPH patients overlapped considerably with those levels in patients with prostate cancer, levels > 100 ng/mL should suggest prostate cancer. The early appearance of elevated serum CgA allows an early change of therapy to be made and can lead to the effective prevention of any further development of metastases. J. Clin. Lab. Anal. 12:20–25, 1998. © 1998. Wiley-Liss, Inc.
Microfibrils in glomerulopathies of children: An ultrastructural study

Extracellular microfibrils were found in 47 per cent. of 360 renal biopsies performed in children with a variety of nephropathies. They were observed in the mesangial matrix and basal lamina. They are 17 to 35 nm in diameter and a few show cross-striations with a periodicity of about 10 nm. They are different from fibrin or interstitial collagen. Their close association with thinner filaments in the mesangial matrix and basal lamina suggests that they are derived from such filaments.
Is There an Afro-American Cognitive Style? An Exploratory Study

This study examined the possibility of a unique Afro- American cognitive style. One hundred seventy-eight ninth grade students stratified by race, sex, and achievement level were administered three cognitive style tasks. Results re vealed a significant difference between Afro-and Euro- American students in their perceptual orientation to the environment. It is suggested that this difference may influ ence the performance patterns reported on nonverbal mea sures.
Structural Determinants of DNA Binding by a P. falciparum ApiAP2 Transcriptional Regulator

Putative transcription factors have only recently been identified in the Plasmodium spp., with the major family of regulators comprising the Apicomplexan Apetala2 (AP2) proteins. To better understand the DNA-binding mechanisms of these transcriptional regulators, we characterized the structure and in vitro function of an AP2 DNA-binding domain from a prototypical Apicomplexan AP2 protein, PF14_0633 from Plasmodium falciparum. The X-ray crystal structure of the PF14_0633 AP2 domain bound to DNA reveals a β-sheet fold that binds the DNA major groove through base-specific and backbone contacts; a prominent α-helix supports the β-sheet structure. Substitution of predicted DNA-binding residues with alanine weakened or eliminated DNA binding in solution. In contrast to plant AP2 domains, the PF14_0633 AP2 domain dimerizes upon binding to DNA through a domain-swapping mechanism in which the α-helices of the AP2 domains pack against the β-sheets of the dimer mates. DNA-induced dimerization of PF14_0633 may be important for tethering two distal DNA loci together in the nucleus and/or for inducing functional rearrangements of its domains to facilitate transcriptional regulation. Consistent with a multisite binding mode, at least two copies of the consensus sequence recognized by PF14_0633 are present upstream of a previously identified group of sporozoite-stage genes. Taken together, these findings illustrate how Plasmodium has adapted the AP2 DNA-binding domain for genome-wide transcriptional regulation.
Misalignment in imaging multifibers.

A statistical approach is used to characterize image transmission through misaligned multifibers, i.e., differently arranged at the input and output faces, leading to a spatially invariant line spread function. The resulting MTF is the product of the MTF for the aligned system and a function characterizing stochastic departures from alignment. The case of circular fibers with Gaussian misalignment is treated theoretically and is found to account satisfactorily for experimentally observed results.
Developing a strategic profile: the pre‐planning phase of strategic management

Purpose – The purpose of this article is to assist strategic planners and managers in developing and utilizing a strategic profile of the firm in order to conduct a SWOT analysis and therein apply its results appropriately.Design/methodology/approach – How are the objectives achieved? This objective is achieved by developing a seven‐step procedure, with templates that assist planners and managers in creating a strategic profile of the firm and then utilizing that profile as a filtering mechanism for a SWOT analysis. The article covers the topics of competitive approach, competitive strategy, organizational structure, leadership, and organizational culture.Findings – The profile may not only be employed as a method for centering a firm's strategic planning and implementation, it may also be used for creating a competitive profile of the firm's competitors.Practical implications – The practical implications of the article indicate the need to attach a pre‐planning stage to the typical strategic management p...
Therapy of viral hepatitis.

Worldwide viral hepatitis is the most common cause of jaundice, chronic liver disease cirrhosis and hepatocellular carcinoma. While important advances have been made in prevention of viral hepatitis,
RECENT DEVELOPMENTS IN THE THEORY OF RULES VERSUS DISCRETION

policymaker. This perspective on rules versus discretion was changed by Kydland and Prescott (1977), who looked at rules as a form of commitment. A commitment amounts to a binding contract, which specifies in advance the actions that someone will take, possibly contingent on some exogenous variables that everyone can observe. In contrast, under discretion, a person promises only to take those future actions that will best further his objectives later on. (Such promises are easy to keep!) Thus, discretion is the special case of a rule or contract in which none of today's provisions restrict a person's future actions. In the area of private business dealings, it is natural to think about optimal forms of contracts, which would not usually be pure discretion. Similarly, for public policy, the perspective becomes the optimal form of rules or prior restrictions - even the smart, benevolent policymaker is likely to desire and use
Enduring changes in brain and behavior produced by chronic amphetamine administration: A review and evaluation of animal models of amphetamine psychosis

Some people who repeatedly use stimulant drugs, such as amphetamine (AMPH), develop an AMPH-induced psychosis that is similar to paranoid schizophrenia. There has been, therefore, considerable interest in characterizing the effects of chronic stimulant drug treatment on brain and behavior in non-human animals, and in developing an animal model of AMPH psychosis. A review of this literature shows that in non-human animals chronic AMPH treatment can produce at least two different syndromes, and both of these have been proposed as animal models of AMPH psychosis. The first syndrome is called 'AMPH neurotoxicity', and is produced by maintaining elevated brain concentrations of AMPH for prolonged periods of time. AMPH neurotoxicity is characterized by what has been termed 'hallucinatory-like' behavior, which occurs in association with brain damage resulting in the depletion of striatal DA and other brain monoamines. The second syndrome is called 'behavioral sensitization', and is produced by the repeated intermittent administration of lower doses of AMPH. Behavioral sensitization is characterized by a progressive and enduring enhancement in many AMPH-induced behaviors, and is not accompanied by brain damage or monoamine depletion. It is argued that the changes in the brain and behavior associated with the phenomenon of behavioral sensitization provide a better 'model' of AMPH psychosis than those associated with AMPH neurotoxicity. Much of the review involves a critical analysis of hypotheses regarding the biological basis of behavioral sensitization. Research on this question has focused on mesotelencephalic DA systems, and suggestions that behavioral sensitization is accompanied by: an increase in postsynaptic DA receptors; an increase in DA synthesis; an increase in DA utilization and/or release; and a decrease in DA autoreceptors, are evaluated. It is concluded that there is not convincing evidence for an increase in postsynaptic DA receptors or in DA synthesis in animals sensitized to AMPH. In contrast, there is strong evidence to support the notion that behavioral sensitization is due to enhanced mesotelencephalic DA release, especially upon re-exposure to the drug. The evidence that this enhancement in DA release is due to autoreceptor subsensitivity was found to be equivocal, and therefore other hypotheses should be entertained. Lastly, evidence is discussed in support of the idea that behavioral sensitization is not unique to the psychopharmacology of stimulant drugs, but may be produced by many environmental stimuli that directly or indirectly activate brain catecholamine systems.(ABSTRACT TRUNCATED AT 400 WORDS)
Dynamical electron-phonon interaction and conductivity in strongly disordered metal alloys

A theory of transport in random metal alloys is presented which focuses on certain model-independent features of the electron-phonon dynamics which have been previously neglected. It is found that in the low-resistivity limit the adiabatic-phonon approximation is valid and the disorder associated with phonons increases the resistivity. In the high-resistivity limit where the weak-scattering approximation breaks down due to incipient Anderson localization, the adiabatic-phonon assumption also fails, and phonons actually assist the mobility, producing an anomalous negative temperature coefficient of resistivity. Model analytical and numerical calculations suggest that this mechanism could be the source of the Mooij correlation between the resistivity and its temperature coefficient. The connection between these results and recent scaling theories of localization is discussed.
Association of patient demographics on quality of life in a sample of adult patients with cardiac arrhythmias.

Identify predictors of quality of life (QOL) in patients with any form of cardiac arrhythmia (CA). Data from the Medical Panel Expenditure Survey were analyzed from 2004 to 2009. Patients aged ≥18 with any form of CA (identified via ICD-9-CM codes) were included. Primary outcomes included the physical and mental component scores (PCS and MCS) of the Short-Form 12 version 2 (SF-12) and EuroQoL-5D (EQ-5D) utility scores (US version). Patient demographics included insurance status, urban status, geographical region, federal poverty level, education, comorbidities, and disease-related risk factors of CA. Approximately 5,750,440 individuals had CA. Non-Hispanic Whites had the highest SF-12 MCS (mean 50.9; p < 0.001 across racial groups) and utility scores (mean 0.76; p < 0.001 across racial groups). Patients with both private and public insurance had significantly higher PCS (p = 0.001) and MCS (p < 0.001) in comparison with patients only covered by public insurance. Patients on antiarrhythmic agents had higher SF-12 MCS (51.4 vs. 48.4; p < 0.001) compared to individuals not on antiarrhythmic agents. Significantly lower QOL existed in specific subpopulations (e.g., patients with only public health insurance, racial/ethnic minorities, and those not exposed to antiarrhythmic agents) within the CA population.
Comparison of clinical and electrophysiologic features of preexcitation syndromes in patients presenting initially after age 50 years with those presenting at younger ages

Although patients may develop arrhythmias due to preexcitation syndromes at any time from the prenatal period to late adulthood, presentation in late adulthood is considered uncommon and has not been well studied. From June 1981 to June 1989, 73 patients were documented to have preexcitation syndromes on the basis of electrophysiologic studies. Those whose initial arrhythmias appeared at an age greater than 50 years (group 1, n = 13) were compared with the remaining 60 patients (group 2). All group 1 patients presented in the setting of acute medical or surgical diseases (n = 7), or chronic cardiac disease (n = 6) commonly associated with middle age and often with atrial arrhythmias; only 13 group 2 patients had underlying illnesses (p = 0.0001). Almost two-thirds of group 2 patients were evaluated because of narrow complex orthodromic tachycardia or palpitations and electrocardiographic evidence of preexcitation. Wide complex tachycardia was more often a reason for referral of older patients (7 of 13 vs 11 of 60, p less than 0.05), among whom atrial fibrillation/flutter also tended to be more frequent (4 of 13 vs 11 of 60, difference not significant). The PR and QRS intervals of group 1 patients were within the normal range and differed significantly from those of group 2 patients (PR, 0.15 +/- 0.04 vs 0.11 +/- 0.03 second, p less than 0.001; QRS, 0.09 +/- 0.01 vs 0.12 +/- 0.03 second, p less than 0.001), making electrocardiographic identification of preexcitation more difficult in group 1. Several factors likely contributed.(ABSTRACT TRUNCATED AT 250 WORDS)
Plasma-induced sputtering of an atmosphere

Magnetospheric ions, solar wind ions, and locally produced pick-up ions can impact the atmospheres of objects in the solar system, transferring energy by collisions with atmospheric atoms and molecules. This can result in an expansion of the atmospheric corona with a fraction of the energetic atoms or molecules being lost (sputtered) from the atmosphere. The expanded corona presents a larger target to the incident plasma, which in turn enhances pick-up ion formation and collisional ejection. In this manner a significant flux of atoms or molecules can be lost from an atmosphere, affecting its long-term evolution. This has been shown to be an important process for the dynamics and evolution of the atmosphere of lo, which is bombarded by the Jovian magnetospheric plasma, and for loss of atmosphere from Titan. Sputtering by pick-up ion bombardment has been shown to remove material from the atmosphere of Mars affecting the observed isotope ratios, and energetic O+ precipitation affects the Earth's thermosphere. The physics of ion bombardment of a gas which leads to atmospheric sputtering is described here. Analytic expressions derived from transport equations are shown to be useful for estimating the sputtering rate. These are compared to results from transport and Monte-Carlo calculations.
Role Of Membrane Cholesterol Content In The Activity Of Cyclooxygenase-2 (COX-2) In MCF-7 Human Breast Cancer Cells

Cyclooxygenase-2 (COX-2) and its product PGE2 are known to increase both angiogenesis and resistance to apoptosis (promoting tumor growth) and to enhance the penetration of cancer cells into adjacent tissues (causing metastasis). Thus, knowing how the activity of COX2 is regulated at the cellular level has implications for breast cancer therapeutic strategies. The goal of this research is to unravel a new molecular mechanism for regulating the activity of COX-2. The proposed molecular mechanism may be elucidated by using the sterol superlattice model. In plasma membranes, arachidonic acid (AA) is released by phospholipase A2 (PLA2). Cyclooxygenase then converts AA to prostaglandins (e.g., PGE2). The activity of PLA2 is known to vary with membrane cholesterol content in an alternating manner, showing a local minimum at critical sterol mole fractions (Cr) for maximal superlattice formation. Hence, it is logical to hypothesize that the activity of COX (including the isoform COX-2) also varies with cholesterol content in a biphasic manner. In this study, the cholesterol content in MCF-7 human breast cancer cells was decreased systematically by using methyl-beta-cyclodextrin. A biphasic change in COX-2 activity, as monitored by the Cayman COX-2 assay with minor modifications, was observed at certain cell cholesterol content Crcell. The cholesterol content near Crcell could serve as a fine-tuning mechanism to regulate COX-2 activity and PGE2 production, and consequently, cancer cell growth and metastasis. (supported by DOD, NSF and PDOH)
ATP Depletion Affects the Phosphorylation State, Ligand Binding, and Nuclear Transport of the 4 S Polycyclic Aromatic Hydrocarbon-binding Protein in Rat Hepatoma Cells

In the rat, cytochrome P4501A1 gene expression is thought to be regulated by several trans-acting factors including the 4 S polycyclic aromatic hydrocarbon (PAH)-binding protein. Phosphorylation and dephosphorylation have been suggested to influence the function of many cytosolic receptors and transcription factors. The ATP level within H4IIE rat hepatoma cells could be depleted by treatment with sodium azide or 2,4-dinitrophenol; restoration of the original ATP levels occurred with addition of glucose to the cell culture. ATP depletion reduced the phosphate content of the 4 S protein by approximately 25-30%, which lowered the binding of benzo[a]pyrene (B[a]P) to the 4 S protein by >60%. This effect could not be reversed by the addition of ATP to the binding reaction mixtures. Alkaline phosphatase treatment of the purified 4 S protein in a cell-free system also reduced the B[a]P binding to the protein. Cells treated with a protein phosphatase inhibitor, okadaic acid, and a protein kinase inhibitor, staurosporin, affected the B[a]P binding of the 4 S protein positively and negatively, respectively. These data suggested that phosphorylation is involved in the interaction of the 4 S protein with the PAH. The nuclear translocation of the predominantly cytosolic binding protein has been investigated after ligand binding. Western blots with the immunopurified 4 S PAH-binding protein from cytosolic and nuclear lysates showed significant differences in the distribution of the 4 S receptor between cytosolic and nuclear compartments in control and ATP-depleted cells. Ligand binding stimulated the movement of the receptor into the nucleus, which was completely blocked by reducing the intracellular ATP concentration. These findings provide new information on the role of ATP and phosphorylation on the interaction of B[a]P with 4 S PAH-binding protein and its nuclear translocation.
Measuring Abuse Sequelae: Validating and Extending the Trauma Symptom Checklist–40

This study used the Trauma Symptom Checklist–40 (TSC–40) to index both childhood sexual abuse (CSA) and childhood physical abuse (CPA) in a college student sample of both men and women (N = 441). Although the TSC–40 was designed as a measure of CSA trauma, this study concludes the measure is appropriately reliable for indexing the traumatic sequelae of CPA as well as CSA in nonclinical samples. This study also explored the effects of gender and abuse severity on resulting symptomatology, finding that women and severely abused individuals report the most negative sequelae. Both CSA and CPA emerged as significant explanatory variables in TSC–40 scale scores beyond gender, supporting its validity for indexing traumatic sequelae in nonclinical samples. Tess M. S. Neal is now at the Department of Psychiatry, University of Massachusetts Medical School and Department of Psychology, Worcester State Hospital.
COMPARISON OP ANTIGEN DETECTION METHODS IN A PRIMATE MODEL OF HEMOPHILUS MEMINGITIS

An infant primate model of H. influenzae b (HIB) infection was employed to compare the sensitivity of two rapid methods to detect infection. Latex particle agglutination (LPA) and CIE assays developed in this laboratory detect 0.5 and 1.0 ng/ml of HID antigen, respectively. Serial quantitative cultures were performed on 19 monkeys with bacteremia and meningitis and corresponding samples tested for antigen. Both assays detected antigen in the serum of all 19 bacteremic animals, with detection a function of duration and density of infection. LPA became positive earlier:70% of animals were LPA+ after 8 hrs of bacteremia and 100% after 36 hrs, compared with 10% and 60% using CIE. After 80 hrs, 84% of sera were CIE+. LPA detected fewer bacteria in blood:after 30 hrs of constant-density bacteremia, 6/6 animals with 102 - 103 cfu/ml were LPA+ while 1/6 was CIE+. CIE became reliable at bacterial concentrations ≥ 104/ml of blood; at 36 hrs, 8/9 such samples were CIE+. CSF was obtained from 18 monkeys within 24 hrs of meningitis onset (mean bacterial conc. 1.4 × 104 cfu/ml CSF). LPA was positive in 15/17 samples, detecting 4/6 containing 102 cfu/ml and all 11 with > 103/ml. CIE was positive in 9/18 samples, detecting 3/12 containing 102 - 103 cfu/ml but 6/6 with > 104/ml. 24 hrs later, LPA was positive in all CSF samples and CIE in 16/18 (84%). We conclude that LPA is superior to CIE, detecting antigen earlier and with fewer bacteria (102 -103 bacteria/ml of serum or CSF).
An examination of the effects of adult age on explicit and implicit learning of figural sequences.

Memory for previously learned figural sequences and item-to-item covariations within figural sequences was examined under explicit and implicit instructional conditions in three age groups: young adults (17–23 years); middle-aged adults (35–45 years); and older adults (55–65 years). In Phase 1 of the experiment, the acquisition phase, half the subjects in each age group learned sequences of three to eight items in which the item-to-item changes conformed to an artificial grammar, and the other half of the subjects in each age group learned strings in which the item-to-item changes were nongrammatical. In Phase 2, the implicit/explicit test phase, subjects made forced-choice judgments about parts of the strings that they learned in Phase 1, under either explicit or implicit instructions. Analyses of Phase 2 data revealed that subjects in both instructional conditions used item-to-item covariations in making decisions about grammatical strings. However, use of previously learned covariations as well as the number of correct judgments about previously learned strings was greater in the explicit condition than in the implicit condition. An age-related deficit was found for explicit recognition of grammarfollowing sequences.
Why are the chemical compositions of living organisms so similar

The partition of elements between seawater and the marine solid phases (organisms and pelagic clays) is basically controlled by the same surface adsorption mechanisms as between soil pore water and the land solid phases (plants and soils). However, the elements in living organisms are separated into ‘biophile’ and ‘biophobe’ groups.