cssi/SciSciGPT-SciSciNet huggingface dataset:
Augmentation by naloxone of efflux of LRF from superfused medial basal hypothalamus

The effects of naloxone and β-endorphin (β-EP) on the efflux of luteinizing hormone releasing factor (LRF) from superfused rat medial basal hypothalamus (MBH) were determined. After an equilibration period of 2.5 hrs with Medium 199 at 37°C 0.5 ml fractions were collected. Infusion of medium containing 150 mM KCl for 10 min produced a prompt 4-fold rise in LRF efflux. Injection of naloxone, but not medium alone, into the system significantly increased the effluent concentration of LRF from female (N = 6) MBH's by 177% (P < 0.01) and from male (N = 5) MBH's by 108% (P < 0.05). Administration of β-EP did not significantly alter LRF efflux. However, β-EP did nullify the LRF-stimulating effect of naloxone, when an equimolar mixture of β-EP and naloxone was injected. We conclude that naloxone-sensitive opiate receptors exert a tonic inhibitory effect on tuberoinfundibular LRF neurons. This action does not require the intermediation of brain centers outside the MBH.
Properties of the lectin from the hog peanut (Amphicarpaea bracteata).

Abstract An N-acetyl- d -galactosamine-specific lectin has been isolated from the two seed forms of the hog peanut (Amphicarpaea bracteata) using an affinity support containing the synthetic type A blood group trisaccharide α- d -GalNAc-(1,3)-[α- l -Fuc-(1,2)]-β- d -Gal (Synsorb A). The affinity-purified lectin appears to be identical in both seed types. Gel filtration on Sephadex G-200 gives a single symmetrical peak corresponding to Mr 135,000. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis shows four subunit forms, each of which contains carbohydrate. Limited amino terminal sequencing indicates heterogeneity in two of the first 10 residues. The lectin contains no cysteine. There are four equivalent, noninteracting GalNAc binding sites per 135,000-Da molecule, having an association constant for methyl N-acetyl-α- d -galactosaminide of 4.0 × 104 m −1. Precipitin and hapten inhibition studies show the lectin to be specific for terminal, nonreducing d -GalNAc units, with a preference for the α-anomer and enhanced specificity for the disaccharide, GalNAcα1,3GalNAc. There is also a single adenine binding site per Mr 135,000 lectin molecule with an association constant of 1.3 × 106 m −1.
Gender, Memory, and Hippocampal Volumes: Relationships in Temporal Lobe Epilepsy

Previous research has suggested bilateral hippocampal support for verbal memory in women with early left-hemisphere injury and that women experience better verbal memory outcome following anterior temporal lobectomy (ATL). The present study investigated two issues: (1) Do women have better verbal memory outcome following ATL compared with men? (2) Are verbal memory abilities differentially supported by the right and left hippocampus in males and females? Verbal memory performance [Wechsler Memory Scale: Logical Memory (LM) savings score] was assessed in 70 patients who underwent ATL. MRI volumetric measurements of the left and right hippocampus were performed. No LM savings score difference was found between groups preoperatively although a statistically significant gender effect (P < 0.04) was found for postoperative LM savings scores. Females displayed better postoperative memory performance, regardless of side of surgery. Preoperative verbal memory performance was not associated with right or left hippocampal volumes in either left or right ATL females, although the right hippocampus was positively associated with memory performance for left ATL males. Hippocampal volumes were not associated with postoperative LM savings scores for any group. Results suggest that prose recall was only modestly influenced by gender and that bilateral hippocampal support for prose recall was not present in our female patients.
Towards the architecture of the chromosomal architects.

MukBEF, the bacterial prototype of eukaryotic condensins and cohesins, has a key role in the global chromosomal organization of Escherichia coli and its close relatives. The recent report of the crystal structure of the MukB head domain in complex with its accessory subunits MukEF clearly demonstrates that MukBEF functions as a macromolecular assembly rather than a set of individual molecules and offers clues on how ATP and MukEF regulate the architecture of this complex.
Characterization of Surfaces Presenting Covalently Immobilized Oligopeptides Using Near-Edge X-ray Absorption Fine Structure Spectroscopy

This study addresses the need for methods that validate the surface chemistry leading to the immobilization of biomolecules and provide information about the resulting structural configurations. We report on the use of near edge x-ray absorption fine structure spectroscopy (NEXAFS) to characterize a widely employed immobilization chemistry that leads to the covalent attachment of a biologically relevant oligopeptide to a surface. The oligopeptide used in this study is a kinase substrate of the epidermal growth factor receptor (EGFR), a protein that is a common target for cancer therapeutics. By observing changes in the π* and σ* orbitals of specific nitrogen and carbon atoms (amide, imide, carbonyl) we are able to follow the sequential reactions leading to immobilization of the oligopeptide. We also show that it is possible to use NEXAFS to extend this characterization method to sub-monolayer densities that are relevant to biological assays. Such an element-specific chemical characterization of small peptides on surfaces fills an unmet need and establishes NEXAFS as useful technique for characterizing the immobilization of small biomolecules on surfaces.
Planet migration and disc destruction due to magneto-centrifugal stellar winds

This paper investigates the influence of magneto-centrifugally driven or simply magnetic winds of rapidly rotating, strongly magnetized T Tauri stars in causing the inward or outward migration of close-in giant planets. The azimuthal ram pressure of the magnetized wind acting on the planet tends to increase the planet's angular momentum and cause outward migration if the star's rotation period P * is less than the planet's orbital period Pp. In the opposite case, P * > Pp, the planet migrates inward. Thus, planets orbiting at distances larger (smaller) than 0.06 au (P * /5 d) 2/3 tend to be pushed outward (inward), where P * is the rotation period of the star assumed to have the mass of the Sun. The magnetic winds are likely to occur in T Tauri stars where the thermal speed of the gas close to the star is small, where the star's magnetic field is strong, and where the star rotates rapidly. The time-scale for appreciable radial motion of the planet is estimated as ∼2-20 Myr. A sufficiently massive close-in planet may cause tidal locking and once this happens the radial migration due to the magnetic wind ceases. The magnetic winds are expected to be important for planet migration for the case of a multipolar magnetic field rather than a dipole field where the wind is directed away from the equatorial plane and where a magnetospheric cavity forms. The influence of the magnetic wind in eroding and eventually destroying the accretion disc is analysed. A momentum integral is derived for the turbulent wind/disc boundary layer and this is used to estimate the disc erosion time-scale as ∼1-102 Myr, with the lower value favoured.
Sensitization by annular surrounds: Spatial summation properties

Abstract Westheimer (1965) has shown that the rod threshold at the center of a 45′ adapting disk can be lowered by adding light to the surrounding annular region. In the present experiment, the total flux within the annular region was held constant, while its spatial distribution was varied. The flux was shown to be less effective in lowering the threshold when concentrated in part of the annular area than when distributed homogeneously over it.
Three-dimensional simulation of optical lithography

A 3-D optical lithography simulator has been developed based on a new ray-string algorithm for dissolution etch-front advancement. This simulator, SAMPLE-3D, integrates a number of process simulators on a workstation while also providing display and print capabilities. SAMPLE-3D has been used to look at 3D resist profiles from 2-dimensional mask patterns, including isolated contacts, isolated islands, and elbow patterns. Simulations have been performed on both positive and negative photoresists, and the effects of resist contrast and surface rate retardation were explored. The correlation between the 2D aerial image and the 3D developed resist profile has been investigated. This includes applications to the printability of defects where the nonvertical resist dissolution effects play a strong role.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Postaudit Study of DBCP and EDB Contamination in the Pearl Harbor Aquifer

A simulation of the transport of dibromochloropropane (DBCP) and ethylene dibromide (EDB) in the vadose zone and ground water was conducted in the Mililani area of central Oahu, Hawaii to revisit the ground water contamination predictions made by researchers at the University of Hawaii in 1988 for selected wells of the Honolulu Board of Water Supply. Examination of sampled DBCP results in these wells indicated a large discrepancy between the observed and predicted concentrations in 1988. Therefore, a postaudit study was initiated in the same area to assist in better defining projected concentrations of contaminants in well waters in the future. With the new data, different modeling approaches were undertaken for simulating flow and contaminant transport in both the vadose and saturated zones. The new simulations indicate travel times of 14–32 years for contaminants to reach the water table, depending on the location. The approximate recovery time of wells in the study area is expected to occur after the y...
The combination of growth hormone with hepatocyte growth factor alters the acute phase response.

Recombinant human growth hormone (rhGH) and hepatocyte growth factor (HGF) have both been shown to individually modulate hepatic acute phase reactant proteins and cytokine expression following trauma through different pathways. Recombinant hGH has also been shown to decrease serum and hepatic HGF concentrations after a thermal injury. We hypothesized that the combination of rhGH plus HGF improves the burn-induced acute phase response. Fifty-six male Sprague-Dawley rats received a 60% TBSA third-degree scald burn and were randomly divided to receive either rhGH (2.5 mg/kg/day sc.) plus HGF (200 microg/kg i.v. every 12 h) or placebo (saline). Rats were sacrificed on post-burn days 1, 2, 5, or 7 and serum constitutive and acute phase proteins, TNF-alpha, IL-1beta, IL-6 and liver total protein measured. Hepatic cytokine gene expression, triglyceride concentration, and hepatocyte proliferation were also measured. In rats receiving rhGH/HGF, serum albumin increased on days 5 and 7 and transferrin on day 7 after burn compared to placebo (P<0.05). Haptoglobin decreased 5 days after burn compared to placebo (P<0.05). RhGH/HGF increased serum TNF-alpha on day 2 after burn, while it decreased serum IL-1beta on day 1 after burn compared with placebo (P<0.05). RhGH/HGF had no effect on hepatic cytokine gene expression compared with placebo. Liver total protein content and hepatocyte proliferation increased on days 1, 2, 5, and 7 after burn with rhGH/HGF treatment (P<0.05). These findings indicate that rhGH in combination with HGF exert additive effects on constitutive hepatic proteins and partial inhibitory effects on acute phase protein and cytokine expression. RhGH/HGF has a strong mitogenic effect on hepatocytes.
Local formulae for Stiefel-Whitney classes

We construct an explicit Cech cocycle representing the k-th Stiefel-Whitney class of a vector bundle. This construction involves only the transition functions of the bundle. We also give local formulae for the secondary Stiefel-Whitney classes. These may be useful in determining whether the Stiefel-Whitney numbers of a flat bundle are zero.
WE-C-I-611-02: Composite Fluorographic System Evaluation

This presentation explores methods for the assessment of total fluorographic system performance as related to typical clinical tasks. Many quantitative imaging system analyses focus on separately evaluating the characteristics of the individual system components. Although there is a place for such individualized characterization in product specification and troubleshooting, image quality depends on the interaction of a number of factors including the focal spot characteristics, the projection geometry of the object of interest, scattered radiation, and the image receptor. To determine how the system will perform requires a composite evaluation that includes the net effect of all components impacting image quality under clinical conditions. This is the intent of the NEMA XR 21–2000 Standard that specifies a procedure and phantom “to benchmark cardiac fluoroscopic and fluorographic performance.” This standard provides a qualitative method of evaluation that is dependent on “trained human observers.” For a quantitative analysis, a generalized systems approach has been developed to determine the GMTF, GNNPS, GNEQ and GDQE. This presentation reviews the mechanics of these methods and explores the advantages as well as limitations of composite system evaluation as opposed to component evaluation. Educational Objectives: 1. To provide an understanding of those factors that influence the image quality of fluorographic systems 2. To describe methods of total system performance evaluation 3. To explore the usefulness and limitations of the NEMA XR 21 standard 4. To review the steps in the determination of the generalized system parameters of GMTF, GNNPS, GNEQ, and GDQE. Partially supported by: NIH Grants R01EB002873 and R01NS43924, Toshiba Medical Systems Corp., and the UB Foundation.
Phage lambda gene Q antiterminator recognizes RNA polymerase near the promoter and accelerates it through a pause site

The positive regulator encoded by phage lambda gene Q is a transcription antiterminator that affects RNA polymerase initiating at the phage late gene promoter, but not at other promoters. We show that this nucleotide-sequence-specific interaction of Q protein and RNA polymerase can occur while the enzyme is pausing after 16 nucleotides of the late gene transcript have been made. Furthermore, Q protein chases RNA polymerase from this early pause site, so that it both recognizes the enzyme and changes its transcription properties at this site. We suggest that the ability of Q-modified RNA polymerase to escape this pause reflects the change that allows it to go through terminators. We also show that NusA protein is required for efficient Q protein activity in vitro.
Nutritional supplements, COX-2 and IGF-1 expression in men on active surveillance for prostate cancer.

Background Nutritional factors are associated with reduced risk of prostate cancer progression, yet mechanisms remain unclear. We examined the effects of lycopene and fish oil supplements versus placebo on the normal prostate microenvironment, among men pursuing active surveillance for low-burden prostate cancer. We hypothesized that lycopene or fish oil supplements would down-regulate insulin-like growth factor-1 (IGF-1) and cyclooxygenase 2 (COX-2) gene expression, respectively, reflecting putative proliferation (IGF-1) and inflammatory (COX-2) pathways relevant to carcinogenesis.
Application of Femtosecond Laser Surgery for the Treatment of Glaucoma

Femtosecond laser pulses can be used to create partial thickness scleral channels that drain aqueous humor into the sub-conjunctival space, showing potential for the treatment of glaucoma. Treatment techniques and in vivo results are discussed.
Collimation of asymmetric laser diode at 450 nm using multimode fiber for speckle reduction through diffractive diffusers

Advancements in laser diode technology have lead to the utilization of lasers in pico-projector systems. These proposed devices would need to take full advantage of the coherent source, while still providing full RGB color. Previous work has been completed analyzing 532 nm green diodes in conjunction with hadamard-matrix diffusers for reducing the disruptive speckle noise caused by coherent sources. In addition to the speckle, many small form factor laser diodes have aspheric or nonsymmetric beam shapes upon excitation. Non-circular beam shapes are difficult, if not impossible, to collimate properly. Collimation and beam symmetry is vital in order to keep the bulk of the sources power in the lower order diffractive modes that form from beam shaping optics such as diffusers and micro-lens arrays. Because of these requirements and unique diode structure, generic spherical lenses will not suffice, leading to new techniques for beam collimation. This paper looks at creating the proper beam shape through the use of multimode fiber optics. The output wave from the fiber is then passed through a diffuser. Speckle contrast measurements will be analyzed for both rotating and stationary instances of the diffuser. In addition, other techniques for creating more functional beam shapes will be evaluated in comparison with a fiber optic setup.
Modeling methodology for supply chain synthesis and disruption analysis

The concept of an integrated or synthesized supply chain is a strategy for managing today's globalized and customer driven supply chains in order to better meet customer demands. Synthesizing individual entities into an integrated supply chain can be a challenging task due to a variety of factors including conflicting objectives, mismatched incentives and constraints of the individual entities. Furthermore, understanding the effects of disruptions occurring at any point in the system is difficult when working toward synthesizing supply chain operations. Therefore, the goal of this research is to present a modeling methodology to manage the synthesis of a supply chain by linking hierarchical levels of the system and to model and analyze disruptions in the integrated supply chain. The contribution of this research is threefold: (1) supply chain systems can be modeled hierarchically (2) the performance of synthesized supply chain system can be evaluated quantitatively (3) reachability analysis is used to evaluate the system performance and verify whether a specific state is reachable, allowing the user to understand the extent of effects of a disruption.
Comparison of Tyrosine Hydroxylase and Preproenkephalin Expression in Rat Adrenal Medullary Explants in Vitro and Transplanted into Subarachnoid Space

When adrenal medullary cells are cultured in vitro, tyrosine hydroxylase (TH) mRNA, preproenkephalin (PPEnk) mRNA, and methionine enkephalin (Mek) immunoreactivity was markedly increased compared with intact adrenal medullary cells in situ, suggesting an increased biosynthesis of catecholamines and enkephalin-containing peptides. In transplanted adrenal medullary cells in vivo, TH mRNA and TH immunoreactivity are still apparent for at least 1 year after transplantation, indicating continued capacity for catecholamine biosynthesis. PPEnk mRNA levels in surviving adrenal medullary grafted cells increased, particularly in the first week after transplantation, and remained above levels found in the intact adrenal gland for at least 1 year after transplantation. These results support other studies in our laboratory, suggesting that adrenal medullary transplants reduce pain by synthesis and secretion of both catecholamines and enkephalin-containing peptides. The differences in expression of TH mRNA and PPEnk mRNA in the adrenal medulla in situ, in explants in culture and in transplants in the spinal subarachnoid space, indicate that the mechanisms regulating the expression of neurohumoral factors depend upon environmental factors extrinsic to the medullary cells themselves.
Doing business in the age of conscious capitalism

Purpose – The purpose of this paper is to describe the concept of “Conscious Capitalism,” which refers to a new, more enlightened approach to business purpose and management.Design/methodology/approach – The paper describes how the context for business has changed in fundamental ways in the past two decades, calling for a new approach to business that reflects rising levels of consciousness among customers and employees as well as multiple and deepening challenges facing the world today. It is imperative that business gets on the right side of society rather than continuing to add to societal burdens, as is too often the case. Conscious capitalism is not synonymous with corporate social responsibility (CSR); since society is recognized as an important, even the primary stakeholder, the core business itself must by definition be socially responsible. A conscious approach to business is based on the adoption of a higher purpose that transcends profits, a stakeholder rather than shareholder orientation, and ...
AN INVESTIGATION OF THE RELATIONSHIPS AMONG LEADER AND FOLLOWER PSYCHOLOGICAL CAPITAL, SERVICE CLIMATE, AND JOB PERFORMANCE

Using a sample of 79 police leaders and their direct reports (264 police followers), this study investigated the relationships of leader and follower psychological capital, service climate, and job performance. Hierarchical linear modeling (HLM) results revealed that leader psychological capital was positively related to follower performance, with this relationship mediated by follower psychological capital. We also found that the follower psychological capital-performance relationship was moderated by service climate such that the relationship was stronger when service climate was perceived to be high versus low. Finally, exploratory HLM analyses indicated that leader and follower psychological capital interacted to positively predict rated performance. We discuss implications of these findings, limitations, and directions for future research.
Hybrid method for stress analysis of finite three-dimensional elastic components

Abstract A new hybrid experimental–analytical/numerical method for stress analysis of a finite three-dimensional elastic component is developed in this paper. It uses the experimentally measured surface stresses and a Green's function method to determine the displacement field (and thus strain and stress fields) in the interior of the component. The method is based on a displacement formulation in three-dimensional elasticity. It is first demonstrated that solving the elasticity problem can be reduced to solving two kinds of Dirichlet problems of Laplace and Poisson equations when the surface stresses become known. These Dirichlet problems are then solved by using Green's function method in potential theory. The solutions are derived in integral forms in terms of the Green function, which is unique for given shape of the engineering component. Green's functions for three typical shapes of a rectangular prism, a solid cylinder and a solid sphere are provided. A sample problem is analyzed to demonstrate applications of the new method. The present method differs from the known boundary integral equation method in elasticity theory. In addition, it can be directly applied to actual engineering components, unlike the model-based photoelasticity method.
Pericarditis Mimicking Tricuspid Valvular Disease

A patient with rheumatoid disease initially had the physical findings of isolated tricuspid stenosis. Postmortem examination demonstrated adhesive pericarditis with localized hemopericardium which compressed the atrioventricular groove in the area of the tricuspid valve. Historical, physical, electrocardiographic, and cardiac catheterization features which suggested the diagnosis are discussed.
Parameter dependence of vortex interactions on a two-dimensional plunging plate

The structure and dynamics of the flow field created by a plunging flat-plate airfoil are investigated at a chord Reynolds number of 10,000 while varying plunge amplitude and Strouhal number. Digital particle image velocimetry measurements are used to characterize the shedding patterns and the interactions between the leading- and trailing-edge vortex structures (LEV and TEV), resulting in the development of a wake classification system based on the nature and timing of interactions between the leading- and trailing-edge vortices. The streamwise advancement of the LEV during a plunge cycle and its resulting interaction with the TEV is primarily dependent on reduced frequency; however, for Strouhal numbers above approximately 0.4, significant changes are observed in the formation of vortices shed from the leading and trailing edges, as well as the circulation of the leading-edge vortex. The functional form of the relationship between leading-edge vortex circulation and Strouhal number suggests that the Strouhal number dependence is more specifically a manifestation of the effective angle of attack. Comparison with low-Reynolds-number studies of plunging airfoil aerodynamics reveals a high degree of consistency and suggests applicability of the classification system beyond the range examined in the present work.
Sorption/desorption of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane(4,4′-DDT) on a sandy loam soil

1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane(4,4′-DDT) is a pesticide well-known for its negative health and environmental effects. Despite being banned by a majority of world countries more than 30 years ago, its persistence in the environment is a continuing problem even today. The objective of the study was the investigation of sorption/desorption behavior of 4,4′-DDT in sandy loam soil. The impact of contaminant concentration and age was observed with three different experiments. The sorption percentages at the end of the short time step (8 h) were 50 and 92 %, for initial concentrations 2.26 and 5.28 mg/L, respectively. When freshly spiked soil was subjected to a conventional sorption study, 82 to 99.6 % of the initial aqueous DDT concentrations were sorbed within 24 h. When modeled with a Freundlich isotherm, the log K f was found to be 3.62. After six consecutive 24 h desorption steps, 33 to 96.6 % still remained in the soil. This was more pronounced for soils that had been aged for 60 days. After seven consecutive 24 h desorption steps of aged soil, the percent remaining sorbed to the soil were 44, 64, and 77 %, for 25, 250, and 500 mg/kg, respectively. All results show that 4,4-DDT has a tendency of sorbing to the soil rapidly and showing resistance to desorption. When comparing desorption values, aged soils were seen to desorb less than non-aged soils. This result was attributed to stronger binding to soil with increased contact time.
Norepinephrine Stimulates Apoptosis in Adult Rat Ventricular Myocytes by Activation of the β-Adrenergic Pathway

Background—Myocardial sympathetic activity is increased in heart failure. We tested the hypothesis that norepinephrine (NE) stimulates apoptosis in adult rat ventricular myocytes in vitro. Methods and Results—Myocytes were exposed to NE alone (10 μmol/L), NE+propranolol (2 μmol/L), NE+prazosin (0.1 μmol/L), or isoproterenol (ISO, 10 μmol/L) for 24 hours. NE and ISO decreased the number of viable myocytes by ≈35%. This effect was completely blocked by the β-adrenergic antagonist propranolol but was not affected by the α1-adrenergic antagonist prazosin. NE increased DNA laddering on agarose gel electrophoresis and increased the percentage of cells that were stained by terminal deoxynucleotidyl transferase–mediated nick end-labeling from 5.8±1.0% to 21.0±2.3% (P<0.01; n=4). NE likewise increased the percentage of apoptotic cells with hypodiploid DNA content as assessed by flow cytometry from 7.8±0.7% to 16.7±2.2% (P<0.01; n=6), and this effect was abolished by propranolol but not prazosin. ISO and forskolin ...
Use of Polymerase Chain Reaction for Successful Identification of Asymptomatic Genital Infection with Herpes Simplex Virus in Pregnant Women at Delivery

The polymerase chain reaction was adapted to the amplification of a herpes simplex virus (HSV) DNA sequence, common to HSV types 1 and 2 (HSV-1, HSV-2). The amplified product was detectable by ethidium-bromide staining or Southern hybridization of gels and by dot hybridization. The HSV polymerase chain reaction detected HSV DNA in samples obtained from eight patients with genital lesions from which HSV-2 was isolated in tissue culture and from four patients with labial lesions from which HSV-1 was isolated. The HSV polymerase chain reaction identified HSV in clinical specimens obtained from 11 women who had asymptomatic genital HSV infections at delivery. None of 11 samples obtained at delivery from women who had antibodies to HSV-2, but whose delivery cultures were negative, were positive by polymerase chain reaction and no false-positive reactions were obtained when the reaction mixture contained human cell DNA or varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, or human papillomavirus DNA.
MOLECULAR DYNAMICS MODEL FOR LASER ABLATION AND DESORPTION OF ORGANIC SOLIDS

A breathing sphere model is developed for molecular dynamics simulations of laser ablation and desorption of organic solids. An approximate representation of the internal molecular motion permits a significant expansion of the time and length scales of the model and still allows one to reproduce a realistic rate of the vibrational relaxation of excited molecules. We find that the model provides a plausible description of the ablation of molecular films and matrix-assisted laser desorption. An apparent threshold fluence has been found to separate two mechanisms for the ejection of molecules: surface vaporization at low laser fluences and collective ejection or ablation at high fluences. Above threshold the laser-induced high pressure and the explosive homogeneous phase transition lead to the strongly forwarded emission of ablated material and high, from 500 up to 1500 m/s, maximum velocities of the ejected plume expansion. Large analyte molecules get axial acceleration from an expanding plume and move along with the matrix molecules at nearly the same velocities. Big molecular clusters are found to constitute a significant part of the ejected plume at fluences right above the ablation threshold. The processes in the plume are found to have a strong influence on the final velocities of ejected molecules and molecular clusters.
The Bayesian Covariance Lasso

Estimation of sparse covariance matrices and their inverse subject to positive definiteness constraints has drawn a lot of attention in recent years. The abundance of high-dimensional data, where the sample size (n) is less than the dimension (d), requires shrinkage estimation methods since the maximum likelihood estimator is not positive definite in this case. Furthermore, when n is larger than d but not sufficiently larger, shrinkage estimation is more stable than maximum likelihood as it reduces the condition number of the precision matrix. Frequentist methods have utilized penalized likelihood methods, whereas Bayesian approaches rely on matrix decompositions or Wishart priors for shrinkage. In this paper we propose a new method, called the Bayesian Covariance Lasso (BCLASSO), for the shrinkage estimation of a precision (covariance) matrix. We consider a class of priors for the precision matrix that leads to the popular frequentist penalties as special cases, develop a Bayes estimator for the precision matrix, and propose an efficient sampling scheme that does not precalculate boundaries for positive definiteness. The proposed method is permutation invariant and performs shrinkage and estimation simultaneously for non-full rank data. Simulations show that the proposed BCLASSO performs similarly as frequentist methods for non-full rank data.
Hermitian Curvature and Plurisubharmonicity of Energy on Teichmüller Space

Let M be a closed Riemann surface, N a Riemannian manifold of Hermitian non-positive curvature, f : M → N a continuous map, and E the function on the Teichmuller space of M that assigns to a complex structure on M the energy of the harmonic map homotopic to f. We show that E is a plurisubharmonic function on the Teichmuller space of M. If N has strictly negative Hermitian curvature, we characterize the directions in which the complex Hessian of E vanishes.
The artificial leaf

To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially separated electron–hole pairs. The holes of this wireless current are captured by the oxygen evolving complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin–NADP+ reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole fuel-forming water-splitting reaction under benign conditions and under 1 su...
Use of a self-administered questionnaire for detection of transient cerebral ischemic attacks: I. Survey of elderly persons living in retirement facilities.

A self-administered questionnaire designed to identify people with transient cerebral ischemia (TIA) in large population groups was distributed to approximately 10,000 elderly persons living in public and private retirement facilities in the United States. The population resided in eight cities, and 74% completed the survey. Transient focal neurological symptoms compatible with a diagnosis of TIA within the previous year were reported by 6.4% of the respondents. Uncertain manifestations of TIA, i.e., dizziness, light-headedness, or loss of balance, were noted by an additional 15.4% the remaining 78.2% had no manifestations of this disorder. A clinical history for TIA was taken by a neurologist in a sample of 1,712 respondents to determine the validity of the questionnaire responses. Thirty (7.1%) of 423 persons presumed by the questionnaire to have TIA met the standard clinical criteria for the diagnosis. An additional 8 cases of TIA were found by the neurologist among the 1,289 interviewed persons presumed by the questionnaire to have uncertain TIA or no evidence of the disorder. The twelve-month period prevalence of TIA was estimated to be 8.2 per 1,000 in the total respondent population and 5.8 per 1,000 among those without a history of prior completed stroke. Despite the high proportion of false-positive neurological symptoms of TIA elicited by the questionnaire, this survey instrument nevertheless screened out for further study the 6% of the population in whom 55% of the TIAs occurred.
Mars: Gravity data analysis of the Crater Antoniadi

Topography and gravity information for this 370-km crater are analyzed to determine a depth of compensation with an Airy isostatic model. A least squares fit to the gravity profile gives an estimate of 115 km for the depth of compensation. It is noted that Antoniadi is the only large Martian crater for which both topographic and gravity data are available for analysis. The goal here is to reduce these geophysical data for additional information on the internal structure of Mars. The results show that if Antoniadi had fully isostatically adjusted, the additional mass material would have been about 100 km below the surface. This is regarded as another data point for geophysicists developing the internal structure of Mars.
Causes and consequences of inhomogeneous dose distributions in radiation therapy

Reasons for delivering a non-uniform dose to the target volume are discussed. These include deliberate tailoring of dose to a non-uniform tumor burden or to a non-uniform expectation of the presence of disease, and undesired but unavoidable non-uniformities due to: technical factors; set-up uncertainty; and the need to avoid sensitive organs abutting the target volume. The consequences of non-uniform dose distributions are reviewed and it is suggested that: tumor control may be better characterized by the mean rather than the minimum target absorbed dose when the dose non-uniformity is not too great; modest dose deficits to small sub-volumes of the target volume may not be too deleterious; and modest dose increments to substantial sub-volumes of the target volume may be advantageous. Further modeling, and animal experiments in which tumors are non-uniformly irradiated are required to validate these hypotheses.
Quantum Theory of Electron Stimulated Desorption

The process of electron stimulated desorption of adsorbates from metal surfaces is investigated within the framework of quantum mechanical scattering theory. The Born-Oppenheimer adiabatic approximation is assumed to be valid for the adsorbate motion. The transition amplitude for desorption via the resonant excitation of excited states of the adsorbate then can be factorized into an electronic excitation amplitude and a Franck-Condon factor. The Franck-Condon factor is more complicated than in molecules. The continuum of substrate excitations coupling to the adsorbate gives rise to an absorptive part of the Born-Oppenheimer potential governing the motion of the adsorbate in the excited state. This absorptive part leads to a considerable reduction of the desorption cross section. Explicit quantum mechanical expressions for the corresponding reduction factor are given.
Avalanche injection and second breakdown in transistors

A rapid type of second breakdown observed in silicon n+-p-n-n+transistors is shown to be due to avalanche injection at the collector n-n+junction. Localized thermal effects, which are usually associated With second breakdown, are shown to play a minor role in the initiation of the transition to the low voltage state. A useful tool in the analysis of avalanche injection is the n+-n-n+diode, which exhibits negative resistance at a critical voltage and current. A close correspondence between the behavior of the diode and the transistor (open base) is established both theoretically and experimentally. Qualitative agreement with the proposed model is obtained for both directions of base current flow. It is shown that transistors having thin, lightly doped collector regions are particularly susceptible to avalanche injection, which suggests that some compromise may be necessary in the design of high-frequency power transistors.
From Taboo to the Negotiable: The Israeli New Historians and the Changing Representation of the Palestinian Refugee Problem

In the last round of the Israeli-Palestinian peace talks at the Taba Conference (January 2001), Israeli negotiators went where no Israeli officials went before: they considered the right of return of Palestinian refugees, and a quasi-statement that acknowledges the Palestinian tragedy and Israel's share of historical responsibility. This paper argues that at least in part this shift in the negotiations' framework can be traced back to the public debate instigated by the work of Israeli New Historians.Michal Ben-Josef Hirsch is a Ph.D. candidate in the Department of Political Science at the Massachusetts Institute of Technology (michal@mit.edu). She thanks Boaz Atzili, Naomi Chazan, Orit Gal, Eran Kaplan, Daniel Levy, Ran Levy, Gil Merom, Clair Moon, Melissa Nobles, Jeremy Pressman, Stephen Van Evera, Amos Zehavi, and two anonymous reviewers for their insightful and helpful comments and suggestions. She also thanks Kezia Avieli-Tabibyan from the Center of Educational Technology (MATAH, Israel) for her valuable assistance with Israeli history textbooks.
Maturation of airway occlusion evoked arousals in sleeping infants: relevance for Sudden Infant Death Syndrome ♦ 1780

Maturation of airway occlusion evoked arousals in sleeping infants: relevance for Sudden Infant Death Syndrome ♦ 1780
Social support and adjustment to university life: A comparison of african-american and white freshmen

The present study assesses patterns of social support of African-American and White freshmen attending a predominantly White university, and the relationship of support to measures of adjustment to university life. African-American students reported significantly less support available than White students, but this difference disappeared when family income was used as a covariate. African-American and White students did not differ in adequacy of social support. Even with family income and prior academic performance covaried, African-American students' college GPAs were significantly lower than White students'. No differences in well-being were found. An understanding of minority students' adjustment to university life necessitates adopting a multidimensional perspective involving social and academic variables and their dynamic interaction.
Tonic vergence and vergence adaptation.

ABSTRACT:In the absence of an adequate visual stimulus, the eyes are typically converged by approximately 0.25 to 0.75 meter angles (MA). This vergence response (VR) was believed to reflect the level of tonic innervation to the extraocular muscles, and accordingly has been termed tonic vergence (TV)
TETHERED CORD IN CHILDREN: A CLINICAL CLASSIFICATION WITH URODYNAMIC CORRELATION

ABSTRACTPurpose: Tethered cord was classified based on clinical presentation and correlated with urodynamic and uroradiographic findings.Materials and Methods: A total of 54 children underwent cord...
My life as an applied social psychologist

I want to describe a personal odyssey that interweaves my career with three main areas of my work: social psychology, program evaluation, and mental health services research. This essay is a personal reflection on the many social, personal, and random factors that influenced the research paths that I followed. The organization is primarily chronological and I pick up the threads that run though my professional life in no particular order. Writing a professional autobiography is by its very nature an egocentric activity. Some who know me will think that this should pose no challenge to me.
Preference for diazepam, but not buspirone, in moderate drinkers.

The purpose of the present study was to determine the preference for buspirone, an anxiolytic predicted to have minimal abuse potential, in comparison with diazepam in moderate drinkers. Preference for diazepam and buspirone was assessed in 55 moderate drinkers using a seven-session procedure consisting of four sampling sessions followed by three choice sessions. On each sampling session subjects ingested five capsules, one every 30 min. Color-coded capsules contained placebo on two sessions and drug on two sessions. Each drug capsule contained diazepam (4 mg) for 30 subjects and buspirone (5 mg) for 25 subjects. On choice sessions subjects chose whichever of the two color-coded capsules, i.e., drug or placebo, they wished to take. After ingesting one capsule, every 30 min they had the option of ingesting another capsule of the same color and content, for a maximum of seven capsules over the session (maximum of 28 mg diazepam or 35 mg buspirone). In the diazepam group 70% of subjects chose diazepam over placebo on at least two of the three choice sessions, whereas in the buspirone group only 24% of subjects chose buspirone over placebo on at least two sessions. Both diazepam and buspirone increased measures of sedation. Only diazepam increased ratings of liking and impaired performance, whereas only buspirone decreased ratings of feeling Friendly. These results replicate previous findings indicating that diazepam has reinforcing effects in moderate drinkers. Further, these results demonstrate the pharmacological specificity of this effect by showing that buspirone did not function as a reinforcer under these same conditions.
A new tool for an old job : Using fixed cell scanning calorimetry to investigate dilute aqueous solutions

Abstract The development of fixed twin cell temperature scanning calorimeters has enabled the more efficient determination of heat capacities of dilute aqueous solutions with a precision comparable to that of the Picker flow heat capacity calorimeters developed nearly 40 years ago. Experiments require less than 0.5 cm 3 of solution, and results can be obtained routinely over the temperature range (278 to 395) K at pressures up to a few bars. Multiple scanning of samples by both increasing and decreasing temperature allows assessment of instrument drift, solute stability, and reproducibility of results. Chemical calibration is essential to take full advantage of the precision and sensitivity of the calorimeters. The calorimetric output is a direct measure of the difference in heat capacity per unit volume of a solution and of a reference liquid, usually water. Thus, densities of the solution and reference liquid are needed to transform the results into heat capacities per unit mass of solution. Examples of solutes that have been investigated include a variety of inorganic and organic compounds that dissolve to give simple ionic or neutral species, or that produce complexes or species that exist in equilibrium distributions that can change as the temperature is scanned. Appropriate selection of the results from experiments on combinations of solutes allows calculation of standard state (zero concentration) thermodynamic quantities for chemical processes and reactions over the ranges of temperature scanned at the solution compositions investigated. Results for a few specific systems are presented and discussed for some representative classes of solutes that have been investigated in our laboratory since 1998.
Synthetic Multinuclear Chromium Assembly Activates Insulin Receptor Kinase Activity: Functional Model for Low-Molecular-Weight Chromium-Binding Substance

The biologically-active form of chromium, low-molecular-weight chromium-binding substance (LMWCr), activates the insulin-dependent tyrosine protein kinase activity of insulin receptor (IR). The sit...
Continuous high-flux monovelocity atomic beam based on a broadband laser-cooling technique

We report application of Hoffnagle's broadband cooling concept to cool Na atoms in an atomic beam. The rms velocity spread of the cooled atoms is 0.75\ifmmode\pm\else\textpm\fi{}0.05 m/s (1.5\ifmmode\pm\else\textpm\fi{}0.2 mK) with a flux of (9.5\ifmmode\pm\else\textpm\fi{}1.0)\ifmmode\times\else\texttimes\fi{}${10}^{8}$ atoms/s. 1D broadband optical molasses is also demonstrated. Potential applications of the cooling scheme are discussed.
Thiol activation of a model O2-aryl diazeniumdiolate prodrug in phospholipid vesicle media.

Abstract Thiolysis of the model diazeniumdiolate prodrug, O2-(2,4-dinitrophenyl) 1-(N,N-diethylamino)diazen-1-ium-1,2-diolate (DNP-DEA/NO, 1), by glutathione (GSH), cysteine (CYSH) and 1-heptanethiol (heptylmercaptan, HM) has been examined in anionic (DOPG), neutral (DPPC, DOPE) and cationic (DOTAP) vesicle media and in glycine buffered aqueous solutions. DOTAP vesicles accelerate the bimolecular reaction with glutathione, cysteine and 1-heptanethiol by factors of 81, 8.2 and 4630, respectively, while reaction is inhibited 5- to 10-fold in the presence of neutral and anionic vesicles. The intrinsic nucleophilicity of the thiols has been compared through the second-order rate constants, 22.9, 5.24 and 43.1 M−1 s−1, for nucleophilic attack on 1 by GS−, CYS− and M−, respectively, obtained in buffered aqueous media. Analysis of the catalysis by DOTAP vesicles, using pseudophase ion-exchange formalism, suggests that the rate increase is due to reactant concentration in the bilayer and interfacial region coupled with enhanced dissociation of the thiol at the vesicle surface. Some contribution from enhanced nucleophilic reactivity at the vesicle interface may also contribute to the greater catalysis by HM. Inhibition of the thiolysis reaction by phospholipid liposomes is attributed to repulsion of the thiolate anions by the negatively charged acyl phosphate of the lipid head group. DOPG = 1,2-dioleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)], DPPC = 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DOPE = 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, DOTAP = 1,2-dioleoyl-3-trimethylammonium-propane.