cssi/SciSciGPT-SciSciNet huggingface dataset:
Learning from the Scatter in Type Ia Supernovae

Type Ia Supernovae are standard candles so their mean apparent magnitude has been exploited to learn about the redshift-distance relationship. Besides intrinsic scatter in this standard candle, additional scatter is caused by gravitational magnification by large scale structure. Here they probe the dependence of this dispersion on cosmological parameters and show that information about the amplitude of clustering, {sigma}{sub s}, is contained in the scatter. In principle, it will be possible to constrain {sigma}{sub s} to within 5% with observations of 2000 Type Ia Supernovae. They identify three sources of systematic error--evolution of intrinsic scatter, baryon contributions to lensing, and non-Gaussianity of lensing--which will make this measurement difficult.
The scheduling of economic lot sizes on volume flexible production systems

Abstract Previous efforts on solving the classical economic lot scheduling problem (ELSP) assume pre-determined and inflexible production rates. Production rates in many cases, such as orders filled by a machine, can be changed. Moreover, unit production cost of an item depends on its production rate. In this paper, we extend the ELSP model to cases where production rates are decision variables. Unit production cost for each item becomes a function of its production rate. We propose an algorithm to find a solution to the modified economic lot scheduling problem for special unit production cost functions and illustrate the results with numerical examples.
Decentralized risk sharing in teams of unmanned vehicles

We investigate the problem of planning for a team of unmanned agents in the presence of constraints. The agents are allowed some probability of violating the constraints, a quantity defined as “risk”. The total risk allowed for the team must be allocated among the constituent agents, and in this work we propose an auctioning mechanism through which agents can bid for risk. Whether a particular bid results in a team performance improvement or not is decided by the agents through consensus. Simple examples suggest a significant improvement in performance, as measured by a reward model, when compared to fixed risk allocations. Monte Carlo simulation results are presented showing an improvement in team performance particularly in environments with tight constraints.
Centers for Disease Control and Prevention growth charts versus breastfeeding

To the Editor .— The 2000 Centers for Disease Control and Prevention growth charts, as described by Ogden et al,1 may unwittingly undermine the national goals for 2010 of having 50% of mothers breastfeeding at 6 months and 25% at 1 year. This will be avoided only if health care providers specifically warn breastfeeding mothers that these charts do not apply to them. Practitioners should use anticipatory guidance to inform parents at 1-, 2-, and 4-month-old well-child visits that these growth charts are based primarily on bottle-fed infants and that their exclusively breastfed infants should be expected to be leaner on the growth chart at their upcoming 6-, 9-, and 12-month visits. These charts do not reflect infant feeding practices today. They are based on NHANES II and III, during which approximately 50% of infants were ever …
Phosphorylation Primes Vinculin for Activation

Vinculin phosphorylation has been implicated as a potential mechanism for focal adhesion growth and maturation. Four vinculin residues—Y100, S1033, S1045, and Y1065—are phosphorylated by kinases during focal adhesion maturation. In this study, phosphorylation at each of these residues is simulated using molecular dynamics models. The simulations demonstrate that once each phosphorylated vinculin structure is at equilibrium, significant local conformational changes result that may impact either vinculin activation or vinculin binding to actin and PIP2. Simulation of vinculin activation after phosphorylation shows that the added phosphoryl groups can prime vinculin for activation. It remains to be seen if vinculin can be phosphorylated at S1033 in vivo, but these simulations highlight that in the event of a S1033 phophorylation vinculin will likely be primed for activation.
Mass Spectrometric Characterization of the Affinity-Purified Human 26S Proteasome Complex†

The 26S proteasome is a multisubunit complex responsible for degradation of ubiquitinated substrates, which plays a critical role in regulating various biological processes. To fully understand the function and regulation of the proteasome complex, an important step is to elucidate its subunit composition and posttranslational modifications. Toward this goal, a new affinity purification strategy has been developed using a derivative of the HB tag for rapid isolation of the human 26S proteasome complex for subsequent proteomic analysis. The purification of the complex is achieved from stable 293 cell lines expressing a HB-tagged proteasome subunit and by high-affinity streptavidin binding with TEV cleavage elution. The complete composition of the 26S proteasome complex, including recently assigned new subunits, is identified by LC-MS/MS. In addition, all known proteasome activator proteins and components involved in the ubiquitin-proteasome degradation pathway are identified. Aside from the subunit composition, the N-terminal modification and phosphorylation of the proteasome subunits have been characterized. Twelve novel phosphorylation sites from eight subunits have been identified, and N-terminal modifications are determined for 25 subunits, 12 of which have not been previously reported in mammals. We also observe different N-terminal processing of subunit Rpn2, which results in identification of two different N-termini of the protein. This work presents the first comprehensive characterization of the human 26S proteasome complex by affinity purification and tandem mass spectrometry. The detailed proteomic profiling obtained here is significant to future studies aiming at a complete understanding of the structure-function relationship of the human 26S proteasome complex.
Keeping Up with the Jones': Decentralization, Policy Imitation, and Industrial Development in China

Abstract Decentralization is often hailed as a means of improving economic policy because it improves the flexibility of policy-making. This article explains why arguments in favor of decentralization, and in particular, theories of market-preserving federalism, may be overstated in this respect. Although economic decentralization may change the incentives of local officials overnight, the impact of local-center relations on the political and economic institutions of a locality is cumulative. The article uses the Chinese auto sector to demonstrate how local institutional arrangements hinder policy change despite decentralization. Local obstacles to change were only overcome by increased international competition.
Egomotion and Vection in Young and Elderly Adults

Background: Elderly people tend to rely upon their visual input more than upon that from other sensory systems due to age-related declines. This reliance upon vision places older adults at risk for falls because they are often not aware of the magnitude of their body motion. Objective: The purpose of this prospective study was to determine the influence of stationary anchors and vection upon egomotion in young, young-old and old adult age groups using the moving room paradigm. Methods: Forty-five healthy participants separated into 3 age groups (young, 18–20 years; young-old, 60–69 years; old, 70–79 years) were tested. Participants stood on a force platform in front of an oscillating virtual moving room. Optical flow fields were presented to the central and peripheral areas of the retina, individually and jointly. Postural motion was assessed through center of pressure (COP). There were 5 room conditions used to evaluate the role of central and peripheral vision upon postural motion. Participants rated their vection, perceived amount of motion, and the magnitude of the visual scene motion following each condition. Results: In all optical flow conditions, old adults produced more postural motion than the young and young-old adults. Participants were quite accurate at rating their postural motion and vection with their COP displacement; however, young adults rated their vection higher, yet produced significantly less COP displacement than the older adults. Postural responses were also decreased in both age groups when portions of the visual scene were occluded in central or peripheral vision. These findings indicate visual sensitivity to visual scene motion as a function of age when information is available to all areas of the retina. Static images in the visual scene provide a reference point which was found to assist in the stabilization of body position, decreasing fall risk. Conclusions: Older adults exhibited increased egomotion, yet decreased vection in response to visual scene motion. It is likely that the reduction in proprioceptive feedback due to healthy aging induces greater COP motion in the older adults before they perceive visual scene motion, placing them at an increased risk for incurring falls.
Productive Efficiency During Transition: Evidence from Bulgarian Panel Data

New and unusually rich panel data for Bulgarian companies during late communism and early transition were used to investigate the determinants of productive efficiency. Compared to conventional production functions, stochastic frontier models were found to be the preferred specifications. Typically, enterprise performance was found to be unaffected by several factors, including the extent of exports, joint venture status, labor management relations and unionization. However, business efficiency was enhanced by incentive compensation arrangements. Compared to fading communism, the determinants of productive efficiency were found not to have changed much during early transition. Average firm efficiency was also investigated and found to be quite low—between 0.603 and 0.720. This dispersion has grown during early transition.J. Comp. Econom.,September 1998, 26(3), pp. 446–464. Hamilton College, Clinton, New York 13323; University of Southern Mississippi, Hattiesburg, Mississippi 39406; Rollins College, Winter Park, Florida 32789.
An experimental determination of the heat of formation of C2 and the CH bond dissociation energy in C2H

Abstract The rotational cutoff levels of C 2 (B′ 1 Σ + g , ν″ = 1,2), produced in the multiphoton dissociation of jet-cooled acetylene at 193 nm, have been measured using laser-induced fluorescence. This data is used to calculate the values Δ H f,0 (C 2 ) = 194.8 ± 0.5 kcal/mol and D 0 (CCH) = 112.0 ± 0.8 kcal/mol, in excellent agreement with the latest theoretical calculations.
Does the Chicago School Need to Expand Its Curriculum

There is much debate among economists and other social scientists about the merits of the "Chicago School" approach to explaining and assessing the operation of legal regimes and other social institutions. In these debates the Chicago School label is rather indiscriminately applied to a quite diverse group of scholars. There is some justification for the use of this term; the persons so described do generally share certain characteristics. They all apply basic microeconomic principles in a relatively rigorous fashion in their analyses of legal questions, and they use much the same basic descriptive categories, behavioral assumptions, and core normative premises. However, within these general contours of agreement there is still significant diversity of outlook and approach. Moreover, few if any Chicago School scholars resemble in any way the pejorative popular caricature of the zealot analyst who uncritically applies basic price theory to describe and evaluate real-world situations without regard to unique local conditions and complexities and without regard to normative principles other than efficiency. Law and Economics: New and Critical Perspectives, a collection edited by Robin Paul Malloy and Christopher Braun, presents a baker's dozen short
Sensitivity to foot shock in autoimmune NZB × NZW F1 hybrid mice

Abstract Prior studies have demonstrated deficits in active avoidance learning in young (12-week-old) mice that develop lupus-like autoimmunity. Because foot shock is the motivating stimulus in this task, sensitivity to foot shock was assessed in autoimmune NZB × NZW F1 hybrid (B/W) and nonautoimmune NZW female mice. Responses to shock at levels ranging from 0.05 to 1.6 mA were recorded twice during the development of autoimmunity. At 12 weeks of age, B/W mice did not differ from NZW mice in sensitivity to shock. Howver, at 24 weeks of age, when antibody levels were elevated, sensitivity to foot shock decreased in B/W mice at low shock levels and increased at high shock levels. A neurological battery revealed no deficits that could account for these effects. However, IgM anti-DNA antibody levels were positively correlated with responsiveness to high levels of shock. The change in the pattern of sensitivity at 24 weeks may be due to a combination of disease-related sensory impairment at low shock levels and hyperalgesia at high shock levels. The response to high levels of shock may also be an indication of enhanced emotionality, an interpretation consistent with reports in other lupus-prone strains and affective disorders in humans with lupus.
High-pressure crystallization and melting of polyethylene in n-pentane

Abstract The fluid–solid phase separation and crystallization in relatively dilute solutions of polyethylene in n -pentane at high pressures were studied using time- and angle-resolved laser light scattering techniques. Majority of the experiments were carried out by cooling (crystallization) or heating (melting) while holding the pressure constant at selected pressures in the range from 10 to 54 MPa. Crystallizations were also carried out via two other pathways: (1) cooling without pressure adjustment and (2) first crossing the L–L phase boundary via pressure reduction at constant temperature followed by cooling. Crystallization and melting transitions were assessed from the variations of the transmitted light intensity or the scattered light intensity (averaged over all angles) with temperature. Kinetics of phase separation during both the crystallization and the melting were followed by the time evolution of the angular distribution of the scattered light intensities. The kinetics were typical of nucleation and growth processes. From the time evolution of the light scattering patterns the mean particle radii and their evolution were also followed. The polymer particles that form upon crystallization were collected and characterized using a field emission scanning electron microscope (FESEM) and differential scanning calorimetry (DSC). The results show that the PE crystals that form from these high-pressure conditions display a plate-like morphology, which tend to aggregate into ellipsoid-shape structures. DSC studies show that the PE crystals show higher crystallinity compared to the original polyethylene sample and display multiple melting peaks during the first heating scan, which however collapse to a single melting transition peak after the initial heating scan. The crystals that formed from the experiments in which L–L phase boundary was crossed first were found to display two distinct particle groups. These were attributed to crystals that form from polymer-rich and polymer-lean phases that form when L–L phase boundary is crossed.
Organics: Evidence of Health Benefits Lacking

Many consumers cite “health and nutritional concerns” as the primary reason for purchasing organic food ([ 1 ][1]). There are several hypotheses to explain why organic foods might be nutritionally superior to conventionally produced foods, including (i) the idea that nutrient uptake is enhanced
Disseminated intravascular coagulation: A review

Disseminated intravascular coagulation (DIC) results from activation of the blood coagulation cascade by various disease processes. DIC may occur with blunt head trauma and, with severe head trauma, may reflect brain parenchymal injury. Oral and maxillofacial surgeons who treat traumatized patients should be aware of the implications of DIC with regard to patient management, diagnosis, and surgical considerations.
The effects of participatory programmes on productivity in selected multinational organisations

This study examines the potential for increasing productivity through the use of participatory programmes in multinational organisations in Saudi Arabia. Three hundred and forty middle managers selected randomly from 100 Saudi Arabian based multinational companies were surveyed. From a total response of 236, 184 usable questionnaires were obtained. Two published, validated instruments on organisational characteristics were used in the study. The findings show that by using participatory programmes and activities, such as team-building and employee participation in decision making and problem solving often increase organisational productivity. Sixty two percent of the respondents expressed an over-whelming support for participative group management system rather than other management approaches.
Nonparabolic subgroups of the modular group

In this paper we shall discuss maximal nonparabolic and maximal normal nonparabolic subgroups of the modular group Г = 〈ω, φ; ω 2 =φ 3 = 1〉. The modular group may also be defined as the group of fractional linear transformations w = ( az+b )/( cz+d ), where a, b, c, d are rational integers with ad − bc = 1. Here, a maximal nonparabolic subgroup of Г is a subgroup that contains no parabolic elements and any proper subgroup of Г which contains S contains parabolic elements. Similarly, a maximal normal nonparabolic subgroup is a normal nonparabolic subgroup of Г which is not contained in any larger normal nonparabolic subgroup of Г.
Efficient numerical simulation for long range wave propagation

We develop an efficient algorithm for simulating wave propagation over long distances with both weak and strong scatterers. In domains with weak heterogeneities the wave field is decomposed into forward propagating and back scattered modes using two coupled parabolic equations. In the region near strong scatterers, the Helmholtz equation is used to capture the strong scattering events. The key idea in our method is to combine these two regimes using a combined domain decomposition and wave decomposition method. A transparent interface condition is derived to couple these two regions together. Numerical examples show that the simulated field is close to the field obtained using the full Helmholtz equation in the whole domain.
Blood Pressure Is Regulated by an α1D-Adrenergic Receptor/Dystrophin Signalosome

Hypertension is a cardiovascular disease associated with increased plasma catecholamines, overactivation of the sympathetic nervous system, and increased vascular tone and total peripheral resistance. A key regulator of sympathetic nervous system function is the α1D-adrenergic receptor (AR), which belongs to the adrenergic family of G-protein-coupled receptors (GPCRs). Endogenous catecholamines norepinephrine and epinephrine activate α1D-ARs on vascular smooth muscle to stimulate vasoconstriction, which increases total peripheral resistance and mean arterial pressure. Indeed, α1D-AR KO mice display a hypotensive phenotype and are resistant to salt-induced hypertension. Unfortunately, little information exists about how this important GPCR functions because of an inability to obtain functional expression in vitro. Here, we identified the dystrophin proteins, syntrophin, dystrobrevin, and utrophin as essential GPCR-interacting proteins for α1D-ARs. We found that dystrophins complex with α1D-AR both in vitro and in vivo to ensure proper functional expression. More importantly, we demonstrate that knock-out of multiple syntrophin isoforms results in the complete loss of α1D-AR function in mouse aortic smooth muscle cells and abrogation of α1D-AR-mediated increases in blood pressure. Our findings demonstrate that syntrophin and utrophin associate with α1D-ARs to create a functional signalosome, which is essential for α1D-AR regulation of vascular tone and blood pressure.
Left ventricular systolic torsion and early diastolic filling by echocardiography in normal humans.

Abstract This study describes a novel 2-dimensional echocardiographic technique to measure left ventricular (LV) systolic twist in humans and relates this measure to early ventricular filling. LV twist is the counterclockwise rotation of the left ventricle during systole when viewed from the apex. The effect of ventricular twist has been postulated to store potential energy, which ultimately aids in diastolic recoil, leading to ventricular suction. The generated negative early diastolic pressures may augment early ventricular filling. We measured ventricular twist in 40 patients with normal transthoracic echocardiograms. End-systolic twist was determined by measuring rotation of the anterolateral papillary muscle about the center of the ventricle. LV filling was assessed by analysis of transmitral Doppler flow velocities. The mean value obtained was 9 ± 7° of rotation. Twist measurements were highly reproducible with an intraobserver correlation coefficient of r = 0.881, p
Determinants of contractile forces generated in disorganized actomyosin bundles

Actomyosin machinery is a fundamental engine consisting mostly of actin filaments, molecular motors, and passive cross-linkers, generating mechanical forces required for biological processes of non-muscle cells such as cell migration, cytokinesis, and morphogenesis. Although the molecular and physical properties of key elements in the actomyosin machinery have been characterized well, it still remains unclear how macroscopic force buildup and dissipation in actomyosin networks and bundles depend on the microscopic properties of individual cytoskeletal components and their local interactions. To bridge such a gap between macroscopic and microscopic scales, we have developed a three-dimensional computational model of actomyosin bundles clamped to an elastic substrate with minimal components: actin filaments, passive cross-linkers, and active motors. Our model accounts for several key features neglected by previous studies despite their significance for force generation, such as realistic structure and kinetics of the motors. Using the model, we systematically investigated how net tension in actomyosin bundles is governed via interplay between motors and cross-linkers. We demonstrated motors can generate large tension on a bundle in the absence of cross-linkers in a very inefficient, unstable manner. Cross-linkers help motors to generate their maximum potential forces as well as enhance overall connectivity, leading to much higher efficiency and stability. We showed further that the cross-linkers behave as a molecular clutch with tunable friction which has quite distinct effects on net tension depending on their cross-linking angles. We also examined the source of symmetry breaking between tensile and compressive forces during tension generation process and discussed how the length and dynamics of actin filaments and the stiffness of the elastic substrate can affect the generated tension.
Dopamine manipulation alters immediate-early gene response of striatal parvalbumin interneurons to cortical stimulation.

Abstract Cortical projections provide the major excitatory inputs to the striatum. In addition to innervating medium spiny cells, these axons contact striatal interneurons that are parvalbumin-immunoreactive (PV-ir). PV-ir interneurons make synaptic connections with many medium spiny cells, and thus can modulate striatal output. The striatum also receives dopaminergic projections from the substantia nigra, but it has been challenging to study the impact of dopamine (DA) cell injury on corticostriatal activity in vivo due to limitations in the methods used to induce cortical activity. Using epidural application of the GABA A antagonist picrotoxin, which produces a topographically restricted region of striatal immediate-early gene expression, we have investigated the effect of DA cell injury or DA receptor antagonism on immediate-early gene (IEG) expression in striatal medium spiny cells and PV-ir interneurons. Epidural application of picrotoxin to the rat's M1 motor cortex induced Fos in ipsilateral dorsolateral striatum. Animals previously given 6-hydroxydopamine (6-OHDA) injections into the ascending DA pathways had greater total numbers of cortical stimulation-induced striatal Fos-ir cells but fewer Fos-ir/PV-ir cells, compared to sham-operates. In a separate experiment, rats given cortical stimulation and treated with the DA D 2 -class antagonist eticlopride (0.10 mg/kg) exhibited fewer Fos-ir/PV-ir cells than did vehicle-treated rats. Taken together, these results indicate that DA may importantly control striatal output via influences on PV-ir interneurons. Possible mechanisms for these influences are discussed.
The role of sucrose-sensitive neurons in ingestion of sweet stimuli by hamsters

Abstract The relationship between sweet preference and activity in sucrose-sensitive chorda tympani nerve fibers was investigated in hamsters (Mesocricetus auratus) . Without exception, hamsters increased consumption of aqueous solutions of nonsweet 0.1 M NaCl, 0.001 M quinine·HCl, 0.01 M citric acid, 0.001 M dithiothreitol, 0.01 M pyridine, 0.01 M 2-phenylethanol, 0.005 M i-amyl acetate, 0.01 M vanillin, half-saturated l-menthol and 0.033 mM capsaicin if they were made sweet by adding 0.5 M sucrose. Since sucrose activates chorda tympani S fibers, activity in these nerve fibers may be sufficient for increased preference. To determine if S-fiber activity is necessary for preference, equally preferred sweet stimuli were presented to the tongue while recording responses of single chorda tympani fibers. S fibers were clearly activated by 0.03 M sucrose, 0.001 M Na saccharin, 0.01 M D-phenylalanine, 0.1 M glycine, 0.005 M dulcin and 0.03 M Na 2-mercaptoethanesulfonate but not by 0.01 M Ca cyclamate and 0.003 M Na 3-nitrobenzenesulfonate. Ca cyclamate weakly activated H fibers and Na 3-nitrobenzenesulfonate weakly activated N fibers. Thus, S-fiber chorda tympani activity may be sufficient but not necessary for sweet preference, which may be influenced by activity in fibers of other taste nerves.
Faraday Rotation for the F Band in KCI

The Faraday rotation was measured in uncolored and colored KCl crystals using a dynamical method. The plane polarized light from a monochromator is focused on the sample that is at the center of a 50-kilogauss superconducting solenoid in a liquid helium Dewar. The transmitted light passes through a rotating polarizer and is detected by a photomultiplier. The resulting alternating signal is compared with a reference signal using an amplitude- independent phase meter, and any change in the plane of polarization is observed as a phase shift. (R.E.U.)
Production and Income Performance of White Leghorn Layers Feed Restricted at Various Stages of Production

Abstract Four feeding programs were conducted to evaluate the effects of feed restriction initiated at different stages of production on performance and economic returns of White Leghorn layers. Program 1 consisted of full feeding from 20 weeks of age. Feeding Programs 2, 3, and 4 consisted of feeding 105 g/bird/day starting at 28, 38, and 45 weeks of age, respectively. Information on production performance and egg grade distributions were collected and used to compare egg returns over feed costs for feed costs of 140, 160, and $180/ton and egg prices of 52, 50, 48 and 26¢ for extra-large, large, medium, and small sizes of eggs. Prices for mediums varied from −2 to −8¢ under large. Early feed restriction (Program 2) resulted in reduced egg production, feed usage, body weights, and average egg weights. Restriction from 38 and 45 weeks (Programs 3 and 4) resulted in levels of egg production comparable to the full-fed hens. Significantly (P
Adult human glial cells can present target antigens to HLA-restricted cytotoxic T-cells.

Abstract T-lymphocyte recognition of antigen either on antigen-presenting cells (APC) necessary for the generation of an immune response or on target cells during the effector phase of a cellular immune response requires expression of HLA molecules. Although immune mechanisms operate in many disease processes of the central nervous system (CNS), cells of the CNS generally express low levels of HLA molecules. In this study, the potential for upregulation of HLA molecules on adult human glial cells was examined. Moreover, the functional implication of this upregulation was assessed by the capacity of glial cells to process and present target antigens to HLA class I-restricted influenza-specific and class II-restrict myelin basic protein (MBP)-specific CTL lines. Glial cells cultured from adult human surgical brain specimens or cells from established glioblastoma multiforme cell lines were studied. Lysis by antigen-specific CTLs was dependent on treatment of the target cell with interferon-γ. The lysis was HLA restricted and antigen specific. The results indicate that adult human glial cells can process and present antigen to HLA-restricted CTLs but require the upregulation of HLA molecules. These findings have implications for infectious and autoimmune diseases of the CNS.
Initial Construction and Validation of the Pathological Narcissism Inventory

The construct of narcissism is inconsistently defined across clinical theory, social-personality psychology, and psychiatric diagnosis. Two problems were identified that impede integration of research and clinical findings regarding narcissistic personality pathology: (a) ambiguity regarding the assessment of pathological narcissism vs. normal narcissism and (b) insufficient scope of existing narcissism measures. Four studies are presented documenting the initial derivation and validation of the Pathological Narcissism Inventory (PNI). The PNI is a 52-item self-report measure assessing 7 dimensions of pathological narcissism spanning problems with narcissistic grandiosity (Entitlement Rage, Exploitativeness, Grandiose Fantasy, Self-sacrificing Self-enhancement) and narcissistic vulnerability (Contingent Self-esteem, Hiding the Self, Devaluing). The PNI structure was validated via confirmatory factor analysis. The PNI correlated negatively with self-esteem and empathy, and positively with shame, interpersonal distress, aggression, and borderline personality organization. Grandiose PNI scales were associated with vindictive, domineering, intrusive, and overly-nurturant interpersonal problems, and vulnerable PNI scales were associated with cold, socially avoidant, and exploitable interpersonal problems. In a small clinical sample, PNI scales exhibited significant associations with parasuicidal behavior, suicide attempts, homicidal ideation, and several aspects of psychotherapy utilization.
Optimizing Methods to Recover Absolute FRET Efficiency from Immobilized Single Molecules

Microscopy-based fluorescence resonance energy transfer (FRET) experiments measure donor and acceptor intensities by isolating these signals with a series of optical elements. Because this filtering discards portions of the spectrum, the observed FRET efficiency is dependent on the set of filters in use. Similarly, observed FRET efficiency is also affected by differences in fluorophore quantum yield. Recovering the absolute FRET efficiency requires normalization for these effects to account for differences between the donor and acceptor fluorophores in their quantum yield and detection efficiency. Without this correction, FRET is consistent across multiple experiments only if the photophysical and instrument properties remain unchanged. Here we present what is, to our knowledge, the first systematic study of methods to recover the true FRET efficiency using DNA rulers with known fluorophore separations. We varied optical elements to purposefully alter observed FRET and examined protein samples to achieve quantum yields distinct from those in the DNA samples. Correction for calculated instrument transmission reduced FRET deviations, which can facilitate comparison of results from different instruments. Empirical normalization was more effective but required significant effort. Normalization based on single-molecule photobleaching was the most effective depending on how it is applied. Surprisingly, per-molecule γ-normalization reduced the peak width in the DNA FRET distribution because anomalous γ-values correspond to FRET outliers. Thus, molecule-to-molecule variation in gamma has an unrecognized effect on the FRET distribution that must be considered to extract information on sample dynamics from the distribution width.
Photochromism of o-Nitrotoluenes

THE crystals of 2-(2′,4′-dinitrobenzyl)-pyridine (I), which are colourless when kept in the dark, turn blue when exposed to light1. Hardwick, Mosher and Passailaigue1 by using a cryoscopic technique have demonstrated that the change in colour is not confined to the crystals but occurs in dilute solutions as well. A similar change in colour has also been observed with 4-(2′,4′-dinitrobenzyl)-pyridine (II)2.
An experimental study of baseline reproducibility and its effect on high-speed sedimentation equilibrium data☆

Abstract Baseline variability is an important source of error in molecular weight determination with the high-speed sedimentation equilibrium method when Rayleigh interference optics are employed. Using Yphantis-style six-channel cell assemblies (1), we have measured this variability under several conditions at 32,000 rpm and below. These measurements have led to the conclusion that the baseline for speeds up to at least 32,000 rpm should be measured from a picture taken at low speed at the end of the high-speed experiment.
Field testing a rapid method for estimating alfalfa quality

Predictive equations for alfalfa quality (PEAQ) based on height of the tallest stem and maturity stage of the most mature stem in a sample were developed to estimate neutral-detergent fiber (NDF) and acid-detergent fiber (ADF) concentrations in alfalfa (Medicago saliva L.). Field testing of these equations is limited outside the state of Wisconsin where they were developed. Our objectives were to test these equations for estimating alfalfa NDF and ADF across a wide geographic area and to evaluate the performance of PEAQ on a whole-field basis by using within-field subsampling. Alfalfa samples varying in height and maturity were collected throughout the growing season from fields in New York (n = 28), Pennsylvania (n = 23), Ohio (n = 48), California (n = 45), and Wisconsin (n = 48) in 1994 to 1996. Additional samples were collected in Ohio and Wisconsin from producer-managed fields in which 5 to 10 subsamples per field were taken on each sampling date (n = 296 subsamples from 51 fields). Observed NDF and ADF values were regressed on estimated values. The accuracy of PEAQ in other states was at least equal to that observed in Wisconsin. Across all states, regression equations for NDF and ADF were slightly biased (b ¬= 1.0 and/or y-intercept ¬= 0 at P < 0.01); however, prediction errors were sufficiently low to allow use of PEAQ as a preharvest management tool. Root mean square error values ranged from 19.1 to 23.9 g kg -1 for NDF and 15.0 to 19.0 g kg -1 for ADF. Prediction errors were 16.2 g kg -1 for NDF and 13.2 g kg -1 for ADF across Ohio and Wisconsin when regressing observed means on estimated means of five subsamples per field-sampling date combination. We conclude that predictive equations for alfalfa quality based on a combination of stem height and maturity were robust across a wide range of environments.
Generation of 8-Epiprostaglandin F by Human Monocytes DISCRIMINATE PRODUCTION BY REACTIVE OXYGEN SPECIES AND PROSTAGLANDIN ENDOPEROXIDE SYNTHASE-2

F2-isoprostanes are free radical-catalyzed products of arachidonic acid. One of these compounds, 8-epiprostaglandin F2alpha (8-epi-PGF2alpha), is a mitogen and vasoconstrictor. We have shown that 8-epi-PGF2 alpha, unlike other F2-isoprostanes, is a minor product of the prostaglandin endoperoxide synthase-1 (PG G/H S-1) expressed in human platelets (Pratico, D., Lawson, J. A., and Fitzgerald, G. A. (1995) J. Biol. Chem. 270, 9800-9808). Human monocytes express PG G/H S-1 constitutively and exhibit regulated expression of PG G/H S-2. Induction of PG G/H S-2 by concanavalin A, the phorbol ester, phorbol 12-myristate 13-acetate, and bacterial lipopolysaccharide was confirmed with a specific antibody in monocytes pretreated with aspirin to inhibit PG G/H S-1. Induction of PG G/H S-2 by all three stimuli coincided with increased formation of prostaglandin E2 (PGE2), thromboxane B2 (TxB2), and 8-epi-PGF2 alpha, but not of other F2-isoprostanes. Confirmation of PG G/H S-2 as the source of 8-epi-PGF2 alpha formation was obtained by down-regulating the enzyme with dexamethasone; preventing protein synthesis with cycloheximide; and preventing synthesis of PGE2, TxB2, and 8-epi-PGF2 alpha with the specific PG G/H S-2 inhibitor, L 745,337. Monocytes also exhibit the facility to generate 8-epi-PGF2 alpha in a free radical-dependent manner. Thus, stimulation with opsonized zymosan or coincubation with low density lipoprotein was unassociated with product formation. However, coincubation of low density lipoprotein with zymosan-stimulated human monocytes resulted in marked formation of 8-epi-PGF2alpha, but not of PGE2 or TxB2. Production of 8-epi-PGF2 alpha coincided with that of thiobarbituric acid-reactive substances and lipid hydroperoxides, but was unaccompanied by PG G/H S-2 induction. Pretreatment of monocytes with the antioxidant, butylated hydroxytoluene or with superoxide dismutase, but not with L 745,337, suppressed formation of 8-epi-PGF2alpha, thiobarbituric acid-reactive substances, and lipid hydroperoxides. In conclusion, human monocytes may form bioactive 8-epi-PGF2alpha either via free radical- or enzyme-catalyzed pathways. 8-Epi-PGF2alpha is a more abundant product of monocyte PG G/H S-2 than of platelet PG G/H S-1. Formation by inducible PG G/H S-2 must be considered as a source of this compound in vivo.
Implicit Motives and Sexual Conservatism as Predictors of Sexual Behaviors

This study was designed to provide an assessment of the relationship between the two most important implicit motives and the most frequently studied sexual behaviors. A community sample of 102 men and 92 women completed measures of implicit power and affiliation-intimacy motives, sexual conservatism, social desirability, and sexual behavior. For men, high power motivation was positively associated with the number of sexual partners and the frequency of sex. There was an interaction between sexual conservatism and power motivation in women. For women low in sexual conservatism, high power motivation was positively associated with the number of sexual partners and with earlier initiation to intercourse and oral sex. There were few associations between affiliation-intimacy motivation and sexual behaviors; however, women high in this motive reported later initiation to oral sex.
Lanthanide porphyrin probes of heme proteins. Insertion of ytterbium (III) mesoporphyrin IX into apomyoglobin.

Abstract Apomyoglobin has been reconstituted with the lanthanide porphyrin complex, ytterbium(III)mesoporphyrin IX. The reconstituted material exhibits absorption and magnetic circular dichroic spectra significantly different from those of the ytterbium porphyrin itself. The sizeable, positive extrinsic Cotton effect in the Soret band of Yb-mesoporphyrin IX induced by the interactions with the globin indicates that the lanthanide porphyrin complex occupies the heme crevice.
Polypropylene fiber–matrix bonds in cementitious composites

It is known that for creating advanced polyolefin/cement-based composites the polymer surface should be converted into a layer which is compatible with the inorganic component. In this respect, plasma chemistry offers additional solutions to the wet chemistry approach. It has been demonstrated during the last decade that cold plasma-mediated reactions are suitable for etching and surface functionalizing even the most inert polymeric substrates, including Teflon, polypropylene (PP), and polyethylene (PE). In this paper composite preparations from SiCl4-cold plasma and chromic acid-treated fibrillated PP substrates and cement are described. The nature of plasma- and wet chemistry-induced surface functionalization and etching processes was monitored using survey and high-resolution X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), and dynamic water contact angle measurements. It has been demonstrated that th...
The first structure of an aldehyde dehydrogenase reveals novel interactions between NAD and the Rossmann fold.

The first structure of an aldehyde dehydrogenase (ALDH) is described at 2.6 A resolution. Each subunit of the dimeric enzyme contains an NAD-binding domain, a catalytic domain and a bridging domain. At the interface of these domains is a 15 A long funnel-shaped passage with a 6 × 12 A opening leading to a putative catalytic pocket. A new mode of NAD binding, which differs substantially from the classic β-α-β binding mode associated with the ‘Rossmann fold’, is observed which we term the β-α,β mode. Sequence comparisons of the class 3 ALDH with other ALDHs indicate a similar polypeptide fold, novel NAD-binding mode and catalytic site for this family. A mechanism for enzymatic specificity and activity is postulated.
Contested canon: Simmel scholarship at Columbia and the new school

The history of sociology exhibits what might be called, after Gallie (1956), an “essentially contested “ canon. The key figures, sacred texts, and central ideas that constitute the sociological tradition are inherently in dispute. This essay examines the “contested canon “ within a historical framework to provide at least a partial explanation for the restricted interpretation of Georg Simmel as a structuralist sociologist. The sites of this contest are two New York City institutions, Columbia University and the New School for Social Research, both of which offered mid-century readings of Simmel’s works. At Columbia in the mid-1950s, Robert K. Merton advanced a structural reading of Simmel’s work. During the same broad period, the New School’s Albert Salomon championed a phenomenological reading of Simmel in his classes and seminars. Despite penetrating insights into Simmel’s links to the phenomenological tradition, Salomon’s interpretation has had less salience than the approach advanced by Merton. The differential success of these competing interpretations is explained in large measure by the institutionalization and dominance of Merton’s research tradition relative to Salomon’s.
Structure-based statistical thermodynamic analysis of T4 lysozyme mutants: structural mapping of cooperative interactions☆

The recent development of a structural parameterization of the energetics of protein folding has permitted the incorporation of the functions that describe the enthalpy, entropy and heat capacity changes, i.e. the individual components of the Gibbs energy, into a statistical thermodynamic formalism that describes the distribution of conformational states under equilibrium conditions. The goal of this approach is to construct with the computer a large ensemble of conformational states, and then to derive the most probable population distribution, i.e. the distribution of states that best accounts for a wide array of experimental observables. This analysis has been applied to four different mutants of T4 lysozyme (S44A, S44G, V131A, V131G). It is shown that the structural parameterization predicts well the stability of the protein and the effects of the mutations. The entire set of folding constants per residue has been calculated for the four mutants. In all cases, the effect of the mutations propagates beyond the mutation site itself through sequence and three-dimensional space. This phenomenon occurs despite the fact that the mutations are at solvent-exposed locations and do not directly affect other interactions in the protein. These results suggest that single amino acid mutations at solvent-exposed locations, or other locations that cause a minimal perturbation, can be used to identify the extent of cooperative interactions. The magnitude and extent of these effects and the accuracy of the algorithm can be tested by means of NMR-detected hydrogen exchange.
Upper limit of grafting conversion and phase homogeneity: cellulose acetate/poly(styrene-co-maleic anhydride) grafting reaction system

Abstract Reactive polymers each bearing large numbers of reactive groups are important for new compatibilized blends with the graft copolymers generated in situ . Potential of gelation and phase homogeneity are two important issues. A case study on cellulose acetate and poly(styrene- co -maleic anhydride) (SMA) was reported here to demonstrate the two issues. It was found that phase homogeneity appears when the grafting conversion of SMA exceeds around 50% for the dispersed SMA phase. There is a relatively narrow range of SMA grafting conversion for the formation of compatibilized ternary mixtures with a homogeneous phase size and a reasonable weight-average molecular weight. The study shows the importance of polydispersity in promoting phase homogeneity due to the weighting towards more grafting of higher-molecular-weight fraction of the reactive polymers.
APCOL: A programming system for computer-controlled psychology laboratories

The development of on-line computer systems can be facilitated by higher-level programming languages that are more powerful and easier to learn than machine-level Assembly languages. In general, it is not possible to speak ofa programming language without also describing the operating system and functional problem domain of the small computer system for which it is intended. This is because of the great variety in the architecture and configuration of small computers. However, it is possible to state more general requirements and design criteria for on-line computer languages in psychology. APCOL is an example of an integrated programming system. One of the important distinguishing features of the system is that it is implemented both on the small-scale laboratory computer and on a large general-purpose computer linked to the smaller machine via a high-speed communications network. This arrangement permits firsthand access to interactive program construction with immediate test of program function by using the on-line implementation as well as access to the text-editing and mass storage facilities of the large-scale machine.
Fast Algorithm and Efficient Architecture for Integer and Fractional Motion Estimation

Motion estimation in H.264/AVC, is done in two parts --- integer motion estimation, and fractional motion estimation. Hardware reuse for both parts is inefficient due to the differences between them. In this paper we address the hardware reuse problem by proposing a, fast motion estimation algorithm as well as a pipelined FPGA-based, field programmable system-on-chip (FPSoC), for integer and fractional motion estimation. Our results show that the rate-distortion loss of our algorithm is insignificant when compared to full search in H.264/AVC. Its average Y-PSNR loss is 0.065 dB, its average percentage bit rate increase is 5 %, and its power consumption is 76 mW. Our FPSoC is hardware-efficient, even out-performing some state-of-the-art ASIC implementations. It can support up to high definition 1280?×?720p video at 24Hz. Thus, our proposed algorithm and architecture is suitable for delivery of high quality video on low power devices and low bit rate applications which typically use H.264/AVC baseline profile@levels 1---3.1.