cssi/SciSciGPT-SciSciNet huggingface dataset:
Low temperature trapping mechanisms in molecular solids using PMDR spectroscopy. III. molecular aggregation and the formation of hexachlorobenzene triplet excimer

The triplet of hexachlorebenzene (HCB) at 1.6 K is found to form only at the defect sites of the crystal lattice. These defects can be created by introducing chemical impurities of higher field energies that of HCB, e.g., other chlorinated or methylated benzene derivatives, or by applying external pressure. The Phosphorescence-Microwave Double Resonance (PMDR) technique is used to study this broad “excimer” type emission. The followin conclusions are made: 1. Since the emission has zf transitions of energies and decay characteristics that are independent of the manner by which the defects are created, it is concluded that the emission must be due to a species involving HCB itself. 2. Since the emission is not observed in undoped pure HCB crystals and its emission intensity is independent of the UV radiation exposure time, it is believe that the emissions is not originated from photochemical products. 3. The observed band width of the zf absorptions and the chlorine quadrupole splittings are similar to those found for the monomer species of HCB and other chlorobenzenes, suggesting that the excited triplet state is not dissociative. The observed diffuseness of the optical spectrum is thus explained in terms of a repulsive ground state potential, thus supporting the assignment of an “excimer” type species. Temperature effects of the HCB triplet excimer emission spectra have been examined from 1.6 to 65 K. The following results are obtained: 1. At temperature higher than 8 K, two new emission maxima appear, replacing the old one in the optical spectrum. This is explained in terms of either the formation of two new excimers of different configurations or emission from vibrationally excited excimer. 2. The intensity of the excimer emission is found to decrease as the temperature increases with an activation energy of 20 cm−1 (which is of magnitude of the frequency of some lattice vibrations). 3. The fact that the emission lifetime decreases at a much slower rate than the emission intensity suggests that the decrease in intensity with temperature is a result of annealing the chemically induced defects and thus decreasing the rate of formation of the excimer. Polarization and lifetimes of the phosphorescence from the individual magnetic sublevels of HCB triplet excimer are determined experimentally. The polarization is predicted group theoretically for both types of excimers made of the translationally “equivalent” and “inequivalent” HCB molecules in the crystal. The results are consistent with an excimer formed from translationally equivalent HCB molecules in the crystal. Using phosphorescence microwave photoexcitation spectroscopy, it was further concluded that the excimer is formed as a result of trapping HCB triplet-rather than singlet-excitons.
A simple and sensitive ribonucleotide reductase assay

Ribonucleotide reductase (RR) is a key regulatory enzyme in the DNA synthesis pathway and is the target of the cancer chemotherapeutic agent hydroxyurea. The study of RR is significantly hindered by the tedious and labor-intensive nature of enzymatic assay. In this report, we present a novel RR assay in which detection of the deoxyribonucleotides produced by RR occurs via coupling to the DNA polymerase reaction, and is enhanced by using RNase to degrade endogenous RNA. Cell extracts from various cell lines were treated with RNase and then reacted with ATP and radioactive ribonucleotide diphosphate as the substrate. Incorporation of the radioactive substrate [14C]CDP into DNA was linear over 30 min and was linear with the amount of extract, which provided RR activity. The reaction was inhibited by hydroxyurea and required Mg2+ and ATP, suggesting that the assay is specific to RR activity. While RR activities determined by our method and by a conventional method were comparable, this novel method proved to be simpler, faster, more sensitive and less expensive. In addition, assay of the RR activity for multiple samples can easily be performed simultaneously. It is superior to other RR assays in all aspects.
SU‐FF‐T‐292: Inter‐Institution Comparison of Patient Quality Assurance Analysis for Tomotherapy

Purpose: HiArt Tomotherapy unit has been used in the clinics for a couple of years. However, the patient‐specific intensity modulated radiotherapy(IMRT)quality assurance (QA) methods vary from center to center. The purpose of this investigation is to analyze and compare the patient specific QA results for the HiArt TomoTherapy between two different institutions. Method and Materials: A patient‐specific IMRT QA procedure was developed and implemented in two different institutions. Once a QA plan is calculated, the dose to a phantom is measured using ion chamber and film. The ion chamber is placed 5 mm below the film which in turn is placed in the equator of a cylindrical solid water phantom. After the plan is delivered to the phantom, the point dose is recorded and the film is processed. Dosimetric analysis is performed after the film and planar dose are co‐registered in the TomoTherapy planning station. In total, sixty‐three patient QA from one center and fifty‐four patients QA from the other were analyzed. Results: For 52.99% of QA measurements done, the difference between measured and calculated doses was less than 1%. In both centers, the patient specific QA tolerance is set to 3%. In total, 92.31% of patient specific QA can pass the QA. Failure to pass the QA can be attributed to: (1) setup uncertainty (2) resolution differences in scanned QA phantom (3) the machine output fluctuation. Conclusions: A comprehensive patient QA program has been developed and the results of 117 patients from two different centers are analyzed in this paper. Given the novel approach of TomoTherapy towards IMRT, it is important to see that for the majority of the patients the deviation between planned and delivered doses is less than 3%.
Growth of dislocation-free ZnSe single crystal by CVT method

Abstract ZnSe single crystals with a diameter of 12 mm and a length of 28 mm were grown by the CVT method using iodine as a transport agent. The ampoule wall, which has direct contact with the crystal during growth, was formed of pBN. The seed crystal, which was the CVT grown ZnSe single crystal with a reduced dislocation density (EPD) of less than 1×10 4 cm −2 , was used. The seed crystal was protected against thermal stress from the ampoule end wall by inserting the undoped polycrystalline ZnSe between the back of the seed crystal and the ampoule end wall. The EPD of the grown ZnSe crystal was less than 1×10 4 cm −2 even near the seed crystal, and reduced to 0 at the tail part of the crystal. The shallow pits were found to exist on the etched surface of dislocation-free part. The dislocation-free part was annealed in Zn atmosphere, and crystallographic, electrical and optical characterizations were evaluated in relation to the annealing conditions.
Bounded cascade models as nonstationary multifractals

We investigate a class of bounded random-cascade models which are multiplicative by construction yet additive with respect to some but not all of their properties. We assume the multiplicative weights go to unity as the cascade proceeds; then the resulting field has upper and lower bounds. Two largely complementary multifractal statistical methods of analysis are used, singular measures and structure functions yielding, respectively, the exponent hierarchies ${\mathit{D}}_{\mathit{q}}$ and ${\mathit{H}}_{\mathit{q}}$. We study in more detail a specific subclass of one-dimensional models with weights 1\ifmmode\pm\else\textpm\fi{}(1-2p)${\mathit{r}}_{\mathit{n}\mathrm{\ensuremath{-}}1}^{\mathit{H}}$ at relative scale ${\mathit{r}}_{\mathit{n}}$=${2}^{\mathrm{\ensuremath{-}}\mathit{n}}$ after n cascade steps. The parameter Hg0 regulates the degree of nonstationarity; at H=0, stationarity prevails and singular ``p-model'' cascades [Meneveau and Sreenivasan, Phys. Rev. Lett. 59, 1424 (1987)] are retrieved. Our model has at once large-scale stationarity and small scale nonstationarity with stationary increments. Due to the boundedness, the ${\mathit{D}}_{\mathit{q}}$ all converge to unity with increasing n; the rate of convergence is estimated and the results are discussed in terms of ``residual'' multifractality (a spurious singularity spectrum due to finite-size effects). The structure-function exponents are more interesting: ${\mathit{H}}_{\mathit{q}}$=min{H,1/q} in the limit n\ensuremath{\rightarrow}\ensuremath{\infty}. We further focus on the cases q=1, related to the fractal structure of the graph, q=2, related to the energy spectrum, and q=1/H, the critical order beyond which our multiplicative (and multiscaling) bounded cascade model can be statistically distinguished from fractional Brownian motion, the corresponding additive (and monoscaling) model. This bifurcation in statistical behavior can be interpreted as a first-order phase transition traceable to the boundedness, itself inherited from the large-scale stationarity. Some geophysical applications are briefly discussed.
Anxiolytic effects of buspirone and gepirone in the fear-potentiated startle paradigm

Fear potentiation of the acoustic startle reflex was produced by eliciting startle responses in the presence of a light that had been previously paired with a shock. Buspirone (0.6–5.0 mg/kg) and gepirone (1.25–10.0 mg/kg), but not their common metabolite, 1-PP (0.5–40 mg/kg), produced a dose-dependent reduction of fear-potentiated startle. These doses of buspirone and gepirone slightly increased baseline startle levels. Reduction of fear-potentiated startle appears to involve supraspinal sites of action, since intraventricular but not intrathecal administration of buspirone (200 μ;g) reduced fear-enhanced startle. Both buspirone and gepirone were highly efficacious in this model compared to other animal tests that are used to study anxiolytic compounds.
Insights from theoretical calculations on structure, dynamics, phase behavior and hydrogen sorption in nanoporous metal organic frameworks

Abstract Metal organic framework (MOF) materials are gaining lot of interest because of their potential as hydrogen storage materials. Due to their nanosize, understanding hydrogen sorption behavior, structural flexibility, phase behavior, etc. is difficult to study by experimental methods. In this situation, various levels of theoretical calculations have provided us with invaluable insights about these materials. However, applying a general theory may not work for these materials due to their complex chemical environment. Thus, modification to the existing theory, developing new potential, and parameterization of force field has been a focus for theoreticians working in this area. In this review we have summarized these theories and the specific requirements that have been instrumental in studying hydrogen sorption in MOFs and their physicochemical properties and present the current knowledge about these materials. We also provide various physical chemical aspects to achieve high hydrogen sorption capacity in MOF materials.
Adenylate cyclase: its probable localization in sarcoplasmic reticulum as well as sarcolemma of the canine heart.

Abstract Cardiac microsomes prepared by two different methods were compared in terms of Ca-binding and Ca-uptake, believed to represent markers for fragmented sarcoplasmic reticulum, and the (Na+ + K+)-activated ATPase activity considered to be a marker for the plasma membrane. Microsomes prepared in dilute buffer (H2O-microsomes) contain two to four times the activity of sarcoplasmic reticulum markers when compared to microsomes prepared in 10% sucrose (suc-microsomes). Conversely, the plasma membrane marker was present in greater amounts in the suc-microsomes. Basal, epinephrine-stimulated and NaF-stimulated adenylate cyclase activities were slightly higher in H2O-microsomes, as was the degree of stimulation by the β-adrenergic agonist. These findings provide evidence that both β-receptor and adenylate cyclase activities may be present in the heart's sarcoplasmic reticulum, as well as in the sarcolemma.
Prenatal ethanol exposure fails to affect stimulus reactivity in the rat

Three groups of male Long-Evans rats, that were the offspring of dams maintained throughout pregnancy on a liquid diet in which 35% of the calories were derived from ethanol, pair fed an isocaloric liquid diet that had maltose-dextrin substituted for the ethanol, or maintained on lab chow and water were used as subjects. All subjects were nursed by foster mothers maintained on lab chow and water throughout pregnancy and lactation. The groups were not found to differ on open field activity or number of approaches to four stimulus objects in an open field at 26–30 days of age, on spontaneous alternation at 50–55 days of age or on response to a novel alley at 55 days of age. It was concluded that in the rat, prenatal ethanol exposure does not result in demonstrable changes in responsivity to stimuli in rats tested after 26 days of age.
An insurance and investment portfolio model using chance constrained programming

Abstract An insurance and investment portfolio model is here formulated in terms of the ‘P-Models’ of Chance Constrained Programming, which is then related to the ‘satisficing concepts’ of Simon. For a given insurers' aspiration level of return on equity and risk levels of violating minimum requirements on return and on cash and liquid assets, we propose a method to maximize the insurers' probability of achieving their aspiration level, subject to two chance constraints and other regulatory and institutional constraints. An empirical example is given, based on the industry's aggregated data for a twenty year period.
Dynamic Performance of C-Block Array Architectures

Abstract The lack of adequate actuators has often been cited as the limiting factor in practical applications of smart structures. C-blocks are a building block actuation architecture that addresses the stroke limitations of stack architectures and the force limitations of bender architectures. Because these actuators are based upon piezoelectric materials, they are well suited for high bandwidth dynamic applications. This paper presents an investigation of the dynamic behavior of a generic C-block array architecture using analytical models derived from a unique transfer matrix method and experiments using four distinctly different types of prototypes. To gain insight into the dynamic behavior of the actuation architecture, a parameter analysis based upon both the models and experiments is given. The behavior of long series is found to display both bending and extensional type of behaviors, which can be well approximated with an appropriate equivalent straight bender model. For shorter series, the performance is more complex and the full analytical model is required. From the analytical models derived in this paper along with the insight gained from the straight bender and parameter analysis, it is possible to design and predict the dynamic performance of a generic C-block actuator for a given application which requires a midrange piezoelectric actuator.
Work Separation Demands and Spouse Psychological Well‐Being

Using family resilience and ecological theories, we examine the relationship between partner work-required travel separations and spouse psychological well-being. The study examines the role of work-organization-provided supports for families and of informal support networks, including marital satisfaction, as factors that can reduce the risks for indicators of poor well-being. The data come from a probability sample survey of 8,056 female spouses of U.S. Army personnel, with considerable variation in the amount of travel-related separations. Findings indicate risks for poor psychological well-being are greater for spouses who experience more frequent work-related separations. Findings also indicate that both work organization support and informal support network connections are significant protective factors for spouses experiencing these separations.
Simultaneous Occurrence of Idiopathic Lipemic Tears and Massive Seborrhea

• A 42-year-old man had idiopathic lipemic tears and massive seborrhea. Recent investigations have shown that cholesterol and other lipids occasionally found in tears are produced by meibomian rather than lacrimal glands. The finding in this patient of hypersecretion by both sebaceous glands and meibomian glands, a sebaceous gland variant, suggests that a common mechanism may regulate secretory control of both of these glands. ( Arch Dermatol 1985;121:112-114)
Caveolae and Vesiculo-Vacuolar Organelles in Bovine Capillary Endothelial Cells Cultured with VPF/VEGF on Floating Matrigel-collagen Gels:

In situ vascular endothelium is characterized by many cytoplasmic vesicles (caveolae) and vacuoles. In venules these are organized into prominent clusters called vesiculo-vacuolar organelles or VVOs. VVOs provide an important pathway for plasma protein extravasation in response to vasoactive mediators. In contrast, cultured endothelial cells isolated from many sources lack VVOs and generally have few caveolae. Our goal was to preserve VVOs in cultured endothelium. Bovine adrenal microvascular endothelial cells (BCEs) cultured on floating Matrigel-collagen Type I gels with vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) exhibited typical VVOs by electron microscopy. Both in vivo and in culture VVOs were caveolin-positive by immunoelectron microscopy. On the basis of caveolin immunostaining, VVOs could also be detected by light (confocal) microscopy. When BCEs were cultured without VPF/VEGF, caveolin staining was finely punctate and electron microscopy confirmed the near absence of VVOs. BCE VVOs were sensitive to N-ethylmaleimide. Other types of endothelium cultured on Matrigel-collagen gels with or without VPF/VEGF exhibited few caveolae and no VVOs. Therefore, preservation of VVOs in cultured endothelium required a specific combination of endothelial cells (BCEs), surface matrix (Matrigel-collagen), and growth factor (VPF/VEGF). These endothelial cells should be useful for in vitro studies of trans-endothelial transport.
Review: nuclear structure and DNA replication.

Abstract DNA replication is a highly conserved process among eukaryotes where it occurs within a unique organelle—the nucleus. The importance of this structure is indicated by the fact that assembly of prereplication complexes on cellular chromatin is delayed until mitosis is completed and a nuclear structure has formed. Although nuclear structure is dispensable for DNA replication in vitro, it does appear to play a role in vivo by regulating the concentration of proteins required to initiate DNA replication, by facilitating the assembly or activity of DNA replication forks, and by determining where in the genome initiation of DNA replication occurs.
Evidence for a δ-class opioid receptor on cells of the immune system

Abstract Opioid receptors have been reported to be present on cells of the immune system. Both opioid receptor-ligand interactions which are reversible by naloxone (classical) and those interactions which are irreversible by naloxone (nonclassical) appear to alter various immunologic parameters through the ligand-receptor interactions. In an effort to characterize opioid receptors (which operate with classical interactions) on cells of the immune system, we employed the δ-class opioid receptor-specific ligand, cis -(+)-3-methylfentanylisothiocyanate (SUPERFIT). We herein report the specific labeling of a protein with a molecular weight of 70,000 Da under reducing conditions (58,000 Da under nonreducing conditions) from both B and T cell-enriched murine splenocytes and peripheral blood lymphocytes. Similar results are demonstrated by human peripheral blood lymphocytes and plastic-adherent (monocyte-enriched) leukocytes.
Morphology of Spitzer 24 μm Detected Galaxies in the UDF: The Links between Star Formation and Galaxy Morphology

We have studied the morphologies of infrared-luminous galaxies at 0.3 ≤ z 1011 L☉]. We find that the high-redshift samples are dominated by galaxies with concentrations similar to local late-type disk galaxies; however, they are significantly more asymmetric than most local galaxies but are similar in both regards to local LIRGs. On average, the high-redshift infrared-active galaxies are slightly more asymmetric than the less active ones, although they do include a significantly higher portion of highly asymmetric (merging?) systems and a lower portion of more concentrated, symmetric ones. The morphological similarity of infrared-active and typical infrared-inactive galaxies at high redshift suggests that they may be from the same parent population, but are in different stages of an episodic star formation process. The similarity between high redshift and local LIRGs suggests that a certain level of asymmetry is generally associated with LIRG-level activity.
Early Surgery in Patients With Mitral Regurgitation Due to Flail Leaflets A Long-term Outcome Study

Background The optimal timing for surgery in patients with mitral regurgitation is disputed. Because of the frequency of left ventricular dysfunction, which is difficult to predict, early surgery has been recommended, but its potential benefits have not been demonstrated. Methods and Results The outcomes of 221 patients (mean age, 65±13 years; 71% males) with flail leaflets diagnosed with two-dimensional echocardiography between 1980 and 1989 who were eligible for operation were analyzed. Group I comprised 63 patients who had early mitral valve surgery (within 1 month after diagnosis). Group II comprised 158 patients initially treated conservatively (80 of whom were operated on later). Group I patients were younger (P=.009), had more symptoms (P<.0001), and were more frequently in atrial fibrillation (P=.023) than group II patients. There was no difference in ejection fraction between the groups. The early surgery strategy was followed by an improved overall survival rate (P=.028) and a lower incidence of...
High rates of daytime respiration in three streams: Use of δ18OO2 and O2 to model diel ecosystem metabolism

Photosynthesis and respiration determine the carbon and oxygen (O-2) balance of ecosystems. Current methods used to estimate ecosystem respiration (ER) do not include diel ER fluctuations, which li ...
Inspissation of secretion, dilatation of the ducts and acini, atrophy and fibrosis of the pancreas in infants

Summary A note is presented on the clinical manifestations of thirty-five infants in whom an advanced lesion of the pancreas was found at necropsy. The lesion is characterized by inspissation of secretion, dilatation of the ducts and acini, atrophy and fibrosis. The need for further information concerning the absorption of fat and especially nitrogen, as well as pancreatic enzymes, as an aid to diagnosis, is suggested.
Implementation of an Activity-Based Costing System in a Small Manufacturing Company

This paper describes the implementation of an Activity-Based Costing (ABC) system in a small, high-technology medical device manufacturing company. We have made an attempt to discuss the problems faced in this endeavour and possible solutions to those problems. This paper demonstrates the benefits derived by implementation of an ABC system in a small manufacturing company. It is also shown that even for a small business producing a low volume of products, there is a possibility of distortions in the true product costs should traditional costing methods be used. We believe that the methodology used can be applied in a wide range of industries with similar characteristics. We also believe that the methodology described can be used by mid-size and large companies. The only difference will be in the scope and complexity of the system.
Chordoid Glioma: A Case Report and Molecular Characterization of Five Cases

Chordoid gliomas are rare, slow-growing neoplasms of the anterior third ventricle. We reported a case of chordoid glioma in a 41-year-old man with obstructive hydrocephalus. Histologically, the tumor consisted of polygonal epithelioid cells admixed with elongated cells in a myxoid stroma. A prominent lymphoplasmacytic infiltrate was present. The tumor cells expressed glial fibrillary acidic protein (GFAP), epithelial membrane antigen (EMA), vimentin, CD31, CD34, epidermal growth factor receptor (EGFR) and S100 but were negative for pankeratin and E-cadherin. The percentage of Ki67 positive cells was approximately 3%. Weak p53 immunoreactivity was seen in less than 10% of the cells. Array comparative genomic hybridization performed on this case, as well as on four other archived cases, showed losses at several loci. Fluorescence in situ hybridization (FISH) confirmed consistent genetic alterations at 9p21 and 11q13. These are the fifth through ninth reported cases of chordoid gliomas with molecular characterization suggesting a distinct genetic origin from other gliomas.
Mutator versus antimutator activity of a T4 DNA polymerase mutant distinguishes two different frameshifting mechanisms.

Classical “antimutator” DNA polymerases of bacteriophage T4 were examined for their effects upon frameshift mutation rates at a number of positions within rII cistrons. Their antimutagenic activities reduced frameshift frequencies at a number of sites, but at other sites the opposite occurred: the mutant polymerases exhibited clear mutator activities. This dichotomy reveals the operation of two distinct mechanisms of frameshift mutagenesis that are correlated with the DNA sequences at the frameshift sites. Frameshift mutants subject to the antimutator effects of the mutant polymerase lie in A:T-run DNA sequences, where mutations presumably arise by means of the interstrand DNA misalignments postulated by classical theory. The frameshift mutants produced by the mutator activity of these same polymerases lie in quasipalindromic DNA sequences, where mutations are postulated to arise by aberrant metabolism of DNA secondary structures such as hairpins.
Reliability and Validity of a Brief Version of Levenson's Locus of Control Scale:

A 9-item locus of control scale was constructed from Levenson's (1974) 24-item locus of control scale. Principal components and second-order factor analyses of responses from 129 undergraduates indicated satisfactory reliability and construct validity of the reduced scale. Structural equation analysis using a scaled measure of perceived risk supported the predictive validity of the reduced scale.
Pyongyang's Survival Strategy: Tools of Authoritarian Control in North Korea

Speculation about the future of the North Korean regime has been intense for nearly two decades. In the 1990s, economic crises and famine led to predictions of the Kim regime's imminent downfall. Today analysts highlight impending famine as well as threats to the regime's position brought by eroding information control. Several theories of authoritarian control help to explain how Kim Jong-il and his family have remained in power and how this might change over time. The Kim regime has employed a variety of authoritarian “tools” to protect itself both from popular revolt and from internal coups. Its social policies, reliance on certain ideas and nationalism, and use of force prevent the onset of revolution. Through numerous other tools (elite co-optation, manipulation of foreign governments for financial aid, and the “coupproofing” of domestic institutions), the regime protects itself from coups d'etat and elite unrest. This framework not only helps to explain the past resilience of the regime, but it sugg...
Transient Transfection with Glutamate-Cysteine Ligase (GLCL) cDNA Attenuates tert-Butyl Hydroperoxide (tBuOOH) Toxicity in Chinese Hamster Ovary (CHO) Cells

Transient Transfection with Glutamate-Cysteine Ligase (GLCL) cDNA Attenuates tert-Butyl Hydroperoxide (tBuOOH) Toxicity in Chinese Hamster Ovary (CHO) Cells
Spectro-isotopic assay of lithium.

The isotope spectrum shift in the 6707.8A resonance line of lithium has been used for the assay of the isotopes Li 6 and Li 7. A hollow cathode source loaded with 4 mg of Li2SO4 is excited at 35 ma using purified helium at about 2- to 3-mm pressure as support gas. Characteristics, such as tube geometry, pressure, sample life, flow rate of gas, current, and anode-cathode spacing have been studied to give reproducible line intensity ratios. Precision of the method based on a 95 percent confidence interval is about 6 percent of the Li 6 content or, by difference, about 0.5 percent of the Li 7 content in natural material.Spectra are obtained with a 21-foot, 30,000 lines per inch grating spectrograph using first order for which the Li 6–Li 7 isotope shift of 0.159A is readily separated. A multiplier phototube (1P28) set on the 4603A lithium line is used in an integrating circuit as an exposure meter.
Effect of pyrolyzation temperature on wood-derived carbon and silicon carbide

The structure of carbon and silicon carbide produced through the pyrolyzation of wood and the subsequent melt-infiltration with silicon was studied as a function of initial carbon pyrolyzation temperature. Scanning electron microscopy, transmission electron microscopy, mercury intrusion porosimetry, X-ray diffraction and Raman spectroscopy were used to characterize material derived from initial carbon pyrolyzation temperatures in the range of 300–2400 °C. It was determined that, although structural differences abound in carbon pyrolyzed at different temperatures, the resulting silicon carbide is independent of the initial temperature of carbon pyrolyzation.
The Influence of Microstructure on the Magnetic Properties in Nanostructured Copt L10 Thin Films

We have applied the Neel’s spin pair potential model to model the dependence of magnetocrystalline anisotropy on the long range order parameter. We have produced CoPt nanoscale thin films, with and without an immiscible second phase, by RF and DC magnetron sputtering. These thin films showed a shoulder in their magnetic hysteresis, indicative of a disordered soft magnetic phase for samples annealed above 600 °C while it was barely detectable in 500-600 °C annealed samples. A (111) texture is observed in as-deposited and annealed films is identified as one of the possible contributions to the lower coercivity squareness S* and perpendicular magnetic properties. Micromagnetic calculations confirmed a poor exchange interaction, identified rotational energy barriers and inferred that the ordered region was not fully ordered. The initial stage of ordering clearly showed a discontinuous type transformation.
Reimagining the Retention Problem: Moving Our Thinking from End-Product to By-Product:

Michael J. Siegel suggests an institutional focus on retention as a natural by-product of student learning and success rather than an end in and of itself.
Issues and Opinions---Those to Whom IT Matters Most: Perspectives of IT Faculty on Curricula, Courses, and Class Materials

This paper presents quantitative and qualitative results from a conference on IT teaching held in May of 2006 in Boston. Participants completed a survey in advance, and the conference consisted of presentations and interactive panel discussions. The conference revealed both heterogeneity and convergence across participants' course offerings, and grounds for both optimism and concern about the health and future of IT curricula within business schools. This paper highlights these tensions, synthesizes and extends data and discussions from the conference, and suggests open questions for faculty who teach IT.
Axiomatic Justification for a Geometric Quality Aggregation Function

A central issue in many decision-making situations is the need to consider multiple factors. A special case of multifactor modeling is the quality aggregation problem, which is to derive an overall quality measurement from a set of component quality measurements. Although much research has been published regarding the components of a quality construct, alternative methods for aggregating quality components have been largely ignored. The function generally used for this aggregation is an arithmetic weighted average. This article proposes four axioms that are intuitively desirable in a quality aggregation function. Concepts are drawn from related disciplines such as utility theory, decision theory, and microeconomics. Empirical evidence is presented to support the axioms. The arithmetic weighted average function is found to be inconsistent with all four axioms. A geometric, or multiplicative, function form is presented as a superior alternative, consistent with the four axioms. Model specification issues and other implications are discussed.
Data‐processing levels and thought disorder in schizophrenia

Abstract It is argued that most experimental studies purporting to demonstrate “thought disorder” in schizophrenia are ambiguous as to interpretation since they fail to distinguish between the various levels of information‐processing at which break‐down can occur. Evidence from various sources is presented which suggests that thought disorder is secondary to a primary slowness in processing information, which in turn leads to continuous loss of information from the short‐term memory system. A technique for testing the theory is suggested. Other theories of thought‐disorder are discussed and it is suggested that these theories relate to phenomena which result from the primary defect.
Target angle optimization for minimum energy spread

Abstract The conditions are examined under which the energy spread in outgoing particles from a nuclear reaction due to finite target thickness is minimized. Physical restrictions on the angle of incidence and emission are explicitly considered and it is shown that the minimum in energy spread does not always occur at the limits. Targets are considered both in transmission and in reflection.
Optimally conditioned Vandermonde matrices

We discuss the problem of selecting the points in an (n×n) Vandermonde matrix so as to minimize the condition number of the matrix. We give numerical answers for 2?n?6 in the case of symmetric point configurations. We also consider points on the non-negative real line, and give numerical results forn=2 andn=3. For generaln, the problem can be formulated as a nonlinear minimax problem with nonlinear constraints or, equivalently, as a nonlinear programming problem.
Neurochemical and neurobehavioral effects of neonatal administration of β-N-methylamino-L-alanine and 3,3,-iminodipropionitrile

Abstract Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that is characterized by a loss of motor neurons in the spinal cord, brain stem, and cortex. The present study examined the neurochemical and neurobehavioral consequences of the neonatal administration of IDPN and BMAA, two neurotoxins previously considered as experimental models of ALS. Sprague–Dawley rat pups (male and female) were injected SC with IDPN or BMAA. The following treatment groups ( n = 5–14 per group) were studied: IDPN [100 mg/kg on postnatal days (PNDs) 2, 4, and 6], BMAA-A (500 mg/kg PND 5 only), BMAA-B (500 mg/kg PND 2 and 5), and BMAA-C (100 mg/kg PND 2 and 5). Neurobehavioral testing was performed and the rats were sacrificed at 101 days of age. Monoamine and amino acid content was measured by HPLC in brain regions and the spinal cord. IDPN treatment impaired the righting reflex and decreased forepaw suspension times. BMAA-A and BMAA-B males exhibited an increase in open field behavior. The hindlimb splay of BMAA-A females was increased. Other significant behavioral and endocrine effects were also seen with neonatal IDPN or BMAA treatment. IDPN females had increased spinal cord content of norepinephrine (NE), serotonin, and 5-hydroxyindoleacetic acid (5-HIAA). IDPN males had no alterations in spinal cord content of NE or Glu, but serotonin and 5-HIAA content were increased. BMAA-A and BMAA-B males also had elevated spinal cord 5-HIAA content whereas females were unaffected. Glu and Asp content in the spinal cord was elevated in the female BMAA-C group. Monoamines were also altered in the cerebellum, mediobasal hypothalamus, and hippocampus by IDPN and BMAA treatment. α 2 -Adrenergic binding sites were increased in the spinal cord by IDPN and in the cerebellum by BMAA treatment. The results of this study clearly demonstrated that both IDPN and BMAA given neonatally can produce changes in motor function and spinal cord neurochemistry, although the pattern of the effects is both treatment and sex dependent. Neonatal exposure to either IDPN or BMAA resulted in permanent changes in adult neurochemistry that may be related to reorganizational effects induced by toxin-mediated neuroplasticity in developing neurons.
Pathological gambling: A review with recommendations

Abstract Pathological gambling is recognized as a mental disorder with explicit diagnostic signs and symptoms. It is a condition widely prevalent and one likely to increase in incidence in the future. The literature is reviewed as to diagnostic signs and symptoms, sub-varieties, epidemiology, and psychometric analysis, as well as psychodynamic, behavioral, group, self-help, and programmatic therapy. Specific recommendations for future research are offered.
Cloning and Expression of the HumanN-Acetylneuraminic Acid Phosphate Synthase Gene with 2-Keto-3-deoxy-d-glycero- d-galacto-nononic Acid Biosynthetic Ability

Abstract Sialic acids participate in many important biological recognition events, yet eukaryotic sialic acid biosynthetic genes are not well characterized. In this study, we have identified a novel human gene based on homology to the Escherichia colisialic acid synthase gene (neuB). The human gene is ubiquitously expressed and encodes a 40-kDa enzyme. The gene partially restores sialic acid synthase activity in a neuB-negative mutant of E. coli and results inN-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-d-glycero-d-galacto-nononic acid (KDN) production in insect cells upon recombinant baculovirus infection. In vitro the human enzyme usesN-acetylmannosamine 6-phosphate and mannose 6-phosphate as substrates to generate phosphorylated forms of Neu5Ac and KDN, respectively, but exhibits much higher activity toward the Neu5Ac phosphate product.
Stealth and cunning: hepatitis B and hepatitis C viruses.

Collectively, the results summarized in this review suggest that HBV acts like a stealth virus early in infection, remaining undetected and spreading until the onset of the adaptive immune response several weeks later. We suspect that the relative invisibility of HBV to the innate sensing machinery of the cells reflects its replication strategy, which sequesters the transcriptional template in the nucleus, entails the production of capped and polyadenylated viral mRNAs that resemble the structure of normal cellular transcripts, and the replicating viral genome is sheltered within viral capsid particles in the cytoplasm and, therefore, does not elicit a response. In contrast, HCV activates a strong intracellular antiviral response in the liver, presumably because it replicates via a dsRNA intermediate in the cytoplasm, where it can readily induce the cellular dsRNA sensing apparatus and initiate the signaling cascade. In turn, this results in the induction of many genes, such as the 2′,5′-oligoadenylate synthetase Mx1, that have known antiviral activity (reviewed in references 128 and 141); TRIM14 and 22, members of the same gene family as TRIM5, which has been shown to be part of the host defense against retroviruses (reviewed in reference 11); and ISG15, which has recently been proposed to have a role in innate immunity (124). Impressively, however, HCV cunningly manages to spread through the liver despite induction of these genes, presumably because its E2, NS3, and NS5A proteins can defeat them. On the other hand, both viruses can be controlled when CD8+ T cells enter the liver, recognize antigen, kill whatever infected cells they encounter, and secrete IFN-γ, which triggers a broad-based cascade that amplifies the inflammatory process and has antiviral activity, at least in HBV-transgenic mice and the HBV and HCV cell culture systems. The unexpected finding that HBV does not modulate host cellular gene transcription and apparently does not induce an innate immune response when spreading through the liver raises the possibility that HBV, unlike HCV and other viruses, has evolved to evade innate immunity by not inducing it rather then actively counteracting it; this, in turn, might leave HBV very sensitive to intracellular antiviral mechanisms when they are induced by the adaptive immune system or an unrelated viral infection. Although we suggest that HBV and HCV infections can be inhibited noncytopathically by the cellular genes that are induced during this process, the identities of those genes, the antiviral mechanisms they elicit, and the unique evasion strategies of each virus remain to be determined, marking a new starting point in the quest to understand the cellular and molecular immunobiology of these viral infections.
Guidelines on the cost-effectiveness of larval control programs to reduce dengue transmission in Puerto Rico.

In developing countries, the lack of a closed water system and adequate refuse disposal has often resulted in a proliferation of water containers that are ideal larval habitats for Aedes ae
An economic model for sustainable harbor trucking

Truck emissions at a port may have a severe impact on neighbors, resulting in a politically sensitive sustainability issue for the port management. Strict emissions controls may adversely affect throughput whereas the lack of strict controls will be unacceptable to local citizens and environmental interests. We develop an economic model minimizing cost of truck emissions control and collateral production changes and apply it to decision making for a port seeking to meet a throughput goal while also attempting to satisfy an emissions constraint. Outcomes predicted by the model allow informed decisions about the impact of controls.
Effects of public opinion on abortion policies and use in the American states.

Ample evidence exists to link public opinion and public policy in regard to health issues and abortion in the US. In order to determine the impact of policies (which reflect public preferences) on citizen behavior research was undertaken to test the following hypotheses: 1) in the presence of public support for abortion policy-makers will impose fewer restrictions; 2) in the presence of public support for abortion and fewer restrictions access will be greater; 3) in the presence of public support fewer restrictions and improved access more abortions will occur; and 4) the impact of public preferences on policies will retain its significance when controls are applied to socioeconomic (and metropolitan) and religious variables. Data were analyzed from a 1993 abortion survey with the ratio of abortions/1000 live births in each state in 1992 serving as the dependent variable. State policies were ranked on a nine-point scale of restrictiveness. Public opinion was measured using 1988 and 1990 responses to National Election Series Senate Panel Studies. Access was measured according to the percentage of counties in a state with abortion providers in 1992. Regression analysis of the data resulted in qualified support of all four of the hypotheses. It was found that religious fundamentalism influences abortion attitudes whereas states with large Catholic populations show an influence of the church on public policy. Further research is warranted into the relationship which exists among public preferences public policy and corresponding public behavior.
Cancer-associated thrombosis.

Purpose of reviewVenous thromboembolic disease (VTE) is an important source of morbidity and mortality in patients with cancer. Activation of coagulation pathways may be a central mechanism for tumor spread and development of aggressive disease. This review will focus on novel risk factors and predi
THE GENETICS AND BIOCHEMISTRY OF FLORAL PIGMENTS

Three major groups of pigments, the betalains, the carotenoids, and the anthocyanins, are responsible for the attractive natural display of flower colors. Because of the broad distribution of anthocyanins (synthesized as part of the flavonoid pathway) among the flowering plants, their biosynthesis and regulation are best understood. However, over the past few years, significant progress has been made in understanding the synthesis and participation of carotenoids (derived from isoprenoids) and betalains (derived from tyrosine) in flower pigmentation. These three families of pigments play important ecological functions, for example in the attraction of pollinating animals. Anthocyanins in particular have also been the target of numerous biotechnological efforts with the objective of creating new, or altering the properties of existing, coloring compounds. The focus of this review is to examine the biosynthesis, regulation, and contribution to flower coloration of these three groups of pigments.
Comparison of Interface Formation for GaAs-on-Si and ZnSe-on-Si

A comparison is made between the interface formed when GaAs is grown heteroepitaxially on Si(100) substrates with that formed for ZnSe-on-Si(100) growth. Results of core level photoemission spectroscopy show that the Si(100) surface reacts with As atoms to form a stable monolayer, but reacts with Se atoms to form the compound SiSe2. Annealing treatments can also give rise to a submonolayer coverage of Se atoms on Si(100). The SiSe2 compound is also seen at the interface between ZnSe and Si. Island formation appears to occur at the beginning of growth for both GaAs-on-Si and ZnSe-on-Si
Prenatal sonographic diagnosis of intracranial haemorrhage: Report of a case with a sinusoidal fetal heart rate tracing, and review of the literature

The sinusoidal fetal heart rate pattern has been described in association with severe fetal anaemia, with fetal hypoxaemia, and with the administration of parenteral narcotics. Here, we report a case of decreased fetal movement in which a sinusoidal tracing was recorded. The sonographic diagnosis of a massive fetal intracranial haemorrhage was made. A non-interventive approach was taken and the fetus died soon after in utero. We review 28 previous cases in which the prenatal sonographic diagnosis of fetal intracranial haemorrhage was made, including the underlying maternal and fetal factors and neonatal outcomes. We propose that the sinusoidal tracing in this case was due to the intracranial bleed and suggest that fetal intracranial haemorrhage be considered in the sonographic evaluation of the fetus with a sinusoidal pattern.
On chip monitoring of via degradation

The delays of paths in a chip can be monitored to detect via voiding. This work relates the probability of failure of individual vias to an increase in delay for monitors of the system using data for 65nm technology. The sensitivity of the trigger point as a function of the failure distribution parameters and the path length has been investigated. A circuit has been designed to detect the onset of chip failure due to via voiding.
Regulation and Function of the Peg3 Imprinted Domain

A subset of mammalian genes differ functionally between two alleles due to genomic imprinting, and seven such genes (Peg3, Usp29, APeg3, Zfp264, Zim1, Zim2, Zim3) are localized within the 500-kb genomic interval of the human and mouse genomes, constituting the Peg3 imprinted domain. This Peg3 domain shares several features with the other imprinted domains, including an evolutionarily conserved domain structure, along with transcriptional co-regulation through shared cis regulatory elements, as well as functional roles in controlling fetal growth rates and maternal-caring behaviors. The Peg3 domain also displays some unique features, including YY1-mediated regulation of transcription and imprinting; conversion and adaptation of several protein-coding members as ncRNA genes during evolution; and its close connection to human cancers through the potential tumor suppressor functions of Peg3 and Usp29. In this review, we summarize and discuss these features of the Peg3 domain.