cssi/SciSciGPT-SciSciNet huggingface dataset:
The administration of 5-fluorouracil by mouth.

When 5-fluorouracil was administered by mouth, concentrations of the drug in blood and urine were comparable to and more sustained than those achieved after parenteral treatment in four of seven subjects. This finding serves as evidence that the same precautions against drug side effects are indicated with oral as with parenteral treatment. Patients with metastases to the bowel or congestive heart failure had poorer absorption of 5-fluorouracil. The findings are evidence that intravenous and oral administration of the drug can result in different levels of 5-fluorouracil in blood. It may be worthwhile evaluating the relationship among blood levels, different patterns of absorption, and therapeutic response as a means of determining the optimal mode of therapy. One patient who failed to respond to intravenous 5-fluorouracil responded to oral 5-fluorouracil. Objective regression of hepatic and other metastases were observed in four patients treated with 5-fluorouracil by mouth.
New trends in e-Business: from B2B to web services

Today the term e-business is often used for describing attempts of using Internet for improving business efficiencies and introducing innovative new business models. Until recently, the major focus of e-business has been around replacing the traditional communication means such as telephone and fax by Internet-based electronic data interchange. The introduction of new standards such as XML (Extensible Markup Language), SOAP (Simple Object Access Protocol), and UDDI (Universal Description, Discovery, and Integration) opened new opportunities for dynamically integrating business processes across corporate boundaries on demand. This architecture is called Web Services, and being pursued by major software vendors such as IBM and Microsoft. Web Services can also be considered as a new component-based, distributed computing architecture. This paper discusses the background of this new trend and explains the individual technologies including XML, SOAP, and UDDI that comprise the basis of Web Services.
Impact of Hurricane Ike on Texas poison center calls.

On September 13, 2008, Hurricane Ike made landfall in Texas, resulting in the mandatory evacuation of 8 counties before landfall and the declaration of disaster areas in 29 counties afterward. This study evaluated whether Hurricane Ike affected the pattern of Texas poison center calls. Texas poison center calls received from the disaster area counties were identified for 3 time periods: August 12 to September 10, 2008 (preevacuation), September 11 to 13, 2008 (evacuation and hurricane landfall), and September 14 to 30, 2008 (postevacuation). For selected types of calls, the mean daily call volume during time periods 2 and 3 was compared with a baseline range (BR) derived from the mean daily call volume during time period 1. During the evacuation and landfall period, gasoline exposure calls were higher than expected (mean 3, BR -1 to 2). During the postevacuation period, higher than expected numbers of calls were observed for gasoline exposures (mean 5, BR -1 to 2) and carbon monoxide exposures (mean 3, BR -1-1). During an evacuation, certain calls such as those involving gasoline exposures may increase. After a hurricane, calls such as those involving carbon monoxide and gasoline exposures may increase. Language: en
Observations on an outbreak of pulmonary Aspergillosis

An account is presented of an illness affecting several persons working in a laboratory. The source of the disorder was traced to a massive growth ofAspergillus fumigatus within the air conditioning system. It could not be determined whether the cases described represent infection by or allergy to the fungus.
Synthesis of Colloidal PbSe/PbS Core−Shell Nanowires and PbS/Au Nanowire−Nanocrystal Heterostructures

The oriented attachment of PbSe nanocrystals results in single-crystalline colloidal PbSe nanowires. The addition of different surfactants allows tailoring nanowire morphology, choosing between straight, zigzag, helical, and branched nanowires. In this work, we studied the formation of coaxial PbSe/PbS core−shell heterostructures and observed Stranski−Krastanov growth regime of PbS shell on PbSe nanowires at low reaction temperature (150 °C) that switched to layer-by-layer epitaxial growth above 180 °C. The protection of PbSe nanowires with a PbS shell substantially improves the nanowire stability against oxidation. We also developed a technique for controllable decoration of colloidal PbSe nanowires with Au nanoparticles and found that the morphology of nanowire template had a strong effect on nucleation and growth of gold nanoparticles.
Sequence analysis of the Candida albicans ADE2 gene and physical separation of the two functionally distinct domains of the phosphoribosylaminoimidazole carboxylase.

An ADE2 genomic clone from the pathogenic fungus, Candida albicans, was isolated by complementation of an Escherichia coli purK mutant and the gene was analysed by DNA sequencing. A 1707 bp open reading frame was identified encoding a polypeptide of 569 amino acids with significant homology to all the known yeast ADE2 genes. Sequence homology to both the E. coli purE and purK genes suggests that the C. albicans ADE2 gene is the result of an evolutionary fusion. The amino-acid sequence comparison showed that the N-terminal domain of the Ade2 protein has a 52·5% identity to PurK, whereas the C-terminal domain has a distinct 64·3% identity to PurE. In order to establish the functional relationship of these two regions, deletion mutants of the Ade2 protein were prepared by recombinant expression of the functional domains, which were tested by complementation of their respective E. coli auxotrophs. The sequence described in this paper has been deposited in the EMBL data library under the Accession Number U69606. © 1997 John Wiley & Sons, Ltd.
Determination of the Refractive Indices of Soot Particles from the Reflectivities of Compressed Soot Pellets

Abstract Abstract-Measurements of the polarized components of the reflectivity of a compressed propane soot pellet are presented which demonstrate that, for wavelengths in the infrared, the reflection is specular and is described by the Fresnel equations. By matching these equations to the full angular variations of the specular reflectivities, an effective refractive index of the soot/air mixture is determined at each wavelength. To deduce the refractive indices of the particles themselves, theories for the optical properties of composites are considered and a new relationship based upon the effective medium theory is introduced. The void fraction near the surface of the pellet must be known. A technique is presented for measuring this voidage by performing image analyses of scanning electronmicrographs of the pellet surface. This value of void is found to be substantially less than the bulk void. The inferred indices of the particles are seen to be sensitiveto the value of the void fraction but somewhat...
The products of ribbon and raw are necessary for proper cell shape and cellular localization of nonmuscle myosin in Drosophila.

Abstract Mutations in the genesribandrawcause defects in the morphology of a number of tissues in homozygous mutant embryos. A variety of tubular epithelial tissues adopt a wide, round shape in mutants and dorsal closure fails. Cells of the normal tubular epithelia are columnar and wedge-shaped, and cells of the epidermis become elongated dorsoventrally as dorsal closure occurs. However, the cells of mutants are round or cuboidal in all of the tissues with mutant phenotypes, consistent with the hypothesis that the products of these genes are required for proper cell shape. Cytoskeletal defects, in particular, defects in myosin-driven contraction of the cortical actin cytoskeleton, could be responsible for the lack of specific cell shapes in mutant embryos. This possibility is supported by our observation that the intracellular localization of nonmuscle myosin to the leading edge of the dorsally closing epidermis is absent or reduced inribandrawmutant embryos. In contrast, the band of actin that is also located at the leading edge is neither eliminated nor interrupted by eitherriborrawmutations. Furthermore, mutations ofzipper,the gene encoding the nonmuscle myosin heavy chain, exhibit mutant phenotypes in most of the same tissues affected byribandraw,and many of the phenotypes are similar to those ofribandraw.Therefore, the products ofribandrawmay be required for proper myosin-driven contraction of the actin cytoskeleton.
Decline in age‐dependent, MK801‐induced injury coincides with developmental switch in parvalbumin expression: Somatosensory and motor cortex

MK801-induced activation of caspase-3 is developmentally regulated, peaking at postnatal day (P) 7 and decreasing with increasing postnatal age thereafter. Further, at P7, cells displaying activation of caspase-3 lack expression of calcium binding proteins (CaBPs). To further explore this relationship, we investigated postnatal expression of calbindin (CB), calretinin (CR) and parvalbumin (PV) in two brain regions susceptible to MK801-induced injury, the somatosensory cortex (S1) and layer II/III of motor cortex (M1/M2). Expression of CB and especially PV was low to absent prior to P7 but substantially increased from P7 through to P21 and adulthood. In contrast, CR expression was more variable at early developmental ages, stabilized to lower levels after P7 and showed a marked decline by P21. The results suggest that not only does calcium buffering capacity increase developmentally but acquisition of enhanced buffering may be one mechanism by which neurons survive agent-induced alterations in calcium homeostasis.
Policy: NIH to balance sex in cell and animal studies

Janine A. Clayton and Francis S. Collins unveil policies to ensure that preclinical research funded by the US National Institutes of Health considers females and males.
An operating system architecture for network processors

Network devices have become significantly more complex in recent years, with the most sophisticated current devices incorporating one or more general-purpose CPUs as part of their hardware. The need for such processing capability is motivated by the desire to move greater amounts of functionality, of ever-increasing complexity, from the host CPU to the network device itself. A significant challenge in doing so is managing the complexity of the software running on the network device. We believe that the complexity of this software has reached the point where it is now on a par with many general-purpose systems, and thus requires the same management infrastructure - an operating system for network processors. In this paper we describe an architecture for such an OS, presenting the features most relevant to network processors and describing similarities to and differences from a general- purpose OS. We present a prototype implementation using an SMP system as a virtual network processor, and show how our prototype was used to evaluate a novel user-space interface to a network device.
Beryllium-7 deposition at Fayetteville, Arkansas, and excess polonium-210 from the 1980 eruption of Mount St. Helens.

Radiochemical measurements of 7Be were carried out for a total of 246 individual rain and snow samples collected at Fayetteville (36°N, 94°W), Arkansas, during the period between September 1979 and December 1984. A sharp increase in the 210Po/7Be ratio in rain observed during the winter and spring months of 1980-1981 was attributed to the fallout of excess 210Po from the May 1980 eruption of Mount St. Helens.
Adolescents and death on television: a follow-up study

Abstract The television viewing habits and perceptions of television violence and death of 712 academically heterogeneous students, grades 6 through 12, from three urban and three rural schools in north Florida were surveyed using a TV questionnaire revised from a prior study. The survey indicated that adolescents enjoy watching violent TV programs but are ambivalent about allowing younger children to watch them, and that two fifths of the deaths occurring on the adolescents' favorite programs were violent. Three fifths of the adolescents reported that death is “often or always” on the news and almost three fourths reported that death in the news is violent. While many of them believe that violence on television is true to life and hence educational, they typically vastly overestimated the number of murders that actually occur in a society. Most of the adolescents preferred not to discuss death with either parents or peers. Some form of death education to alleviate or lessen death-related fears is indicat...
A Statistical Approach to Reduce Hospital-Associated Infections

﻿Development of an effective means to control hospital-associated infections remains a major concern to the healthcare industry. Although statistical process control techniques have been used to monitor these infections, no effort has been made to syste..
Role of Precipitation Chemistry Versus Other Watershed Properties in Wisconsin Lake Acidification

Data for over 100 watershed properties, including aspects of topography, hydrology, geology, soils, vegetation, lake morphometry and input precipitation chemistry, have been developed since 1980 for 316 watersheds in northern Wisconsin. The hypothesis being evaluated for this lake population is that the observed water chemistry, can be accounted for as a function of antecedent water and chemical inputs, after considering exchange processes in the lake and watershed and the lake/groundwater interactions. The variables found by regression analysis to explain observed variability in color, sulfate, and acid neutralizing capacity (ANC) levels in Wisconsin lakes are: for color, vegetative characteristics, mean depth, and water renewal times; for sulfate, precipitation concentration of sulfur, evaporative concentration, and lake water renewal time; ANC appears to be controlled by the size of the watershed, lake depth or water renewal time, and the intensity of anthropogenic inputs and cultural developments in the watershed. These results differ from previous studies in Wisconsin and nearby areas of Michigan and Minnesota by indicating that in some lakes acidity may not be in equilibrium with current precipitation chemistry.
Mediterranean neo‐democracies and the opinion‐policy nexus

This article empirically evaluates the previously unresearched relationship between mass public opinion and public policy in the Mediterranean neo‐democracies. By studying almost 250 issues over the last decade, the nature of contemporary democracy in Spain, Portugal and Greece is revealed in relation to the overall consistency between majority preferences and government action. In addition, the opinion‐policy nexus is explored in regard to the potential impact of alternative institutional structures, landslide majorities, different categories of issues (e.g., redistributive, foreign policy), and the partisan composition of the government (i.e., socialist versus non‐socialist).
Images in clinical medicine. Pellegrini-Stieda syndrome.

This 38-year-old man had an incomplete spinal cord injury due to a diving accident some years earlier. He reported new pain in the left knee.
Landing, perching and taking off from vertical surfaces

An approach is presented whereby small, unmanned aircraft can land on walls. The approach is demonstrated with a plane that uses an ultrasonic sensor to initiate a pitch-up maneuver as it flies toward a wall. The plane contacts the wall with spines that engage asperities on the surface. A non-linear suspension absorbs the kinetic energy while keeping the spines attached. A planar dynamic model is used to evaluate pitch-up maneuvers and determine suspension parameters that satisfy constraints on the contact forces for a range of flight velocities. Simulations conducted using the model are compared with data obtained using high-speed video and a force plate embedded in a wall.
Mathematical models to evaluate retention and transport of chromium (VI) in soil

Abstract Modeling the transport of reactive heavy metals in soils requires a mathematical description of the kinetics of various sorption processes. A family of models has been developed that can potentially describe the retention and transport of heavy metals in soils. These models include MRM (a multireaction model applicable to batch studies that includes parallel, reversible, nonlinear kinetic and equilibrium retention reactions), MRTM (MRM incorporated into the convection-dispersion equation for solute transport in soils under steady-state water flow), and SOTS (a two-site model applicable to batch and column studies that includes two parallel, reversible, second-order kinetic retention reactions). All the models include an irreversible, first-order kinetic reaction. Batch kinetic and column transport studies were conducted to evaluate the ability of these models to describe the retention and transport of Cr(VI) in three soils. Both MRM and SOTS described kinetic Cr(VI) retention data from batch experiments equally well. However, MRM rate coefficients from batch experiments could not be used to predict Cr(VI) breakthrough curves (BTCs) from column transport experiments when the soil retained a significant amount of solute. This was because MRM rate coefficients were pseudo rate coefficients that varied with initial solute concentration. SOTS rate coefficients from batch experiments could be used to approximate BTCs for Cr(VI). The second-order kinetic model, which accounts for the concentrations of reaction sites in soils, is a more realistic description of apparent retention processes. However, differences in mass transfer processes between batch and column studies will continue to limit the usefulness of batch-derived rate coefficients in predicting transport of reactive solutes in soils.
Ethylene-tetrafluoroethylene (ETFE) cotelomer iodides and their transformation to surface protection intermediates

Abstract A new class of fluorotelomers was synthesized via the cotelomerization of ethylene and tetrafluoroethylene (TFE) with 1H,1H,2H,2H-perfluoroalkyl iodides. The telomerization led to ethylene-tetrafluoroethylene (ETFE) cotelomer iodides with the incorporation of ethylene and TFE in the cotelomer chain in an alternating fashion. By controlling the reaction parameters such as total pressure, temperature, feed ratio of the monomers, initiator feed, and conversion rate, eight-carbon cotelomer iodide or higher cotelomers could be produced preferably. The ETFE cotelomer iodides were transformed to a variety of intermediates such as alcohols, azides, amines and thiols, precursors useful to make surface modification agents.
Posttraumatic stress symptoms and brain function during a response-inhibition task: an fMRI study in youth.

Youth who experience interpersonal trauma and have posttraumatic stress symptoms (PTSS) can exhibit difficulties in executive function and physiological hyperarousal. Response inhibition has been identified as a core component of executive function. In this study, we investigate the functional neuroanatomical correlates of response inhibition in youth with PTSS. Thirty right-handed medication-naive youth between the ages of 10 and 16 years underwent a 3-Tesla Functional Magnetic Resonance Imaging scan during a response-inhibition (Go/No-Go) task. Youth with PTSS (n = 16) were age and gender matched to a control group of healthy youth (n = 14). Between-groups analyses were conducted to identify brain regions of greater activation in the No/Go-Go contrasts. PTSS and control youth performed the task with similar accuracy and response times. Control subjects had greater middle frontal cortex activation when compared with PTSS subjects. PTSS subjects had greater medial frontal activation when compared with control subjects. A sub-group of youth with PTSS and a history of self-injurious behaviors demonstrated increased insula and orbitofrontal activation when compared with those PTSS youth with no self-injurious behaviors. Insula activation correlated positively with PTSS severity. Diminished middle frontal activity and enhanced medial frontal activity during response-inhibition tasks may represent underlying neurofunctional markers of PTSS. Depression and Anxiety 0:1–13, 2007. Published 2007 Wiley-Liss, Inc.
Word length and lexical activation: Longer is better.

Many models of spoken word recognition posit the existence of lexical and sublexical representations, with excitatory and inhibitory mechanisms used to affect the activation levels of such representations. Bottom-up evidence provides excitatory input, and inhibition from phonetically similar representations leads to lexical competition. In such a system, long words should produce stronger lexical activation than short words, for 2 reasons: Long words provide more bottom-up evidence than short words, and short words are subject to greater inhibition due to the existence of more similar words. Four experiments provide evidence for this view. In addition, reaction-time-based partitioning of the data shows that long words generate greater activation that is available both earlier and for a longer time than is the case for short words. As a result, lexical influences on phoneme identification are extremely robust for long words but are quite fragile and condition-dependent for short words. Models of word recognition must consider words of all lengths to capture the true dynamics of lexical activation.
LES of turbulent square jet flow using an MRT lattice Boltzmann model

In this paper we consider the application of multiple-relaxation-time (MRT) lattice Boltzmann equation (LBE) for large-eddy simulation (LES) of turbulent flows. The implementation is discussed in the context of 19-velocity (D3Q19) MRT-LBE model in conjunction with the Smagorinsky subgrid closure model. The MRT-LBE-LES is then tested in the turbulent square jet flow case. We compare MRT-LBE-LES results with (a) single-relaxation-time (SRT) or BGK LBE results and (b) experimental data. Computed results include the distribution of centerline mean streamwise velocity, jet spread, and spanwise profiles of mean streamwise velocity in the near-field region. The phenomenon of axis switching is investigated. The advantages of MRT over SRT are demonstrated. Reasonable agreement between our numerical results and experimental data demonstrate that the MRT-LBE is a potentially viable tool for LES of turbulence.
The evolution of a contemporary academic health care system.

The story I wish to tell today is of the emergence, over the last two centuries, of an integrated academic health care delivery system from the foundations of this country's fourth medical school, New Hampshire's first major hospital, and a multidisciplinary practice group, unique in its time. I will trace the convergence of each of these into a system that we offer as an answer to the contemporary puzzle of how to provide the best available care at value and still support the academic missions of education and research. We believe this to be the current dilemma of American medicine, and while our answer may not be either successful or universally applicable, we are committed to the attempt. As background, let me provide some perhaps familiar details of the growth of these Hanover [NH] and Lebanon [NH] institutions. DARTMOUTH MEDICAL SCHOOL The remarkable story of the career of Nathan Smith,
Isolation of Oligomannose-Type Glycans from Bean Glycoproteins

Abstract We have isolated individual oligosaccharyl-asparagine derivatives from the total soluble glycoproteins from kidney beens ( Phaseolus vulgaris ) and from lima beans ( Phaseolus limensis ). The protein/glycoprotein mixture was digested exhaustively by pronase, and the glycan-containing fractions were separated from free amino acids and peptides by gel filtration. The oligosaccharyl-asparagine derivatives were finally fractionated on Dowex 50 (C. C. Huang, H. E. Meyer, and R. Montgomery, Carbohydr. Res. 13, 127-137, 1970), and the individual fractions were characterized by mass spectrometry, NMR, and ion exchange chromatography. With the procedures described, only oligomannose derivatives were obtained from the beans. In the case of kidney beans, six different derivatives were observed and characterized, Man 9 GlcNAc 2 Asn, two positional isomers of Man 8 GlcNAc 2 Asn, two positional isomers of Man 7 GlcNAc 2 Asn, and Man 6 GlcNAc 2 Asn. Under identical conditions the lima beans yielded primarily the Man 9 GlcNAc 2 Asn derivative along with a small amount of the two Man 8 GlcNAc 2 Asn derivatives. The oligomannose structures can be isolated in reasonable quantities (2-20 mg) from about 200 g of dry beans.
An in vitro evaluation of the growth of human periodontal ligament fibroblasts after exposure to a 4-META-containing methacrylate-based endodontic sealer.

Abstract Introduction In this study we evaluated the cytotoxic effects of MetaSEAL, a 4-META–containing meth-acrylate-based endodontic sealer, on human periodontal ligament (HPDL) fibroblasts. There are a limited number of studies on the cytotoxic effects of MetaSEAL, and there are no studies on the cytotoxic effects of MetaSEAL on cells it might come into contact with in vivo . Methods MetaSEAL concentrations of 25, 50, 100, 200, 400, and 800 μg/mL were exposed to HPDL fibroblast cultures and evaluated at 1, 3, 7, 14, and 21 days. Controls included untreated cells and cells treated with ethanol, the vehicle for MetaSEAL suspension. Crystal violet staining in 24-well plates and the fluorescence-based CyQUANT Cell Proliferation Assay in 96-well plates assessed fibroblast viability. Results Significant cytotoxicity against HPDL growth by MetaSEAL was both time- and concentration-dependent. At day 1 there were no significant cytotoxic effects, whereas by day 3, 800 μg/mL concentration, by day 7, 200, 400, and 800 μg/mL concentrations, and by day 14, 50, 100, 200, 400, and 800 μg/mL concentrations were significantly cytotoxic. By day 21, all concentrations were significantly cytotoxic. These findings were confirmed by both the crystal violet and CyQUANT assays. Conclusions MetaSEAL endodontic sealer has increasing HPDL cytotoxicity with both concentration and time exposure.
Actual working mechanisms of smart metamaterial structures

Here we present methods for modeling, analysis, and design of metamaterial beams for broadband vibration absorption/isolation. The proposed metamaterial beam consists of a uniform isotropic beam with many small spring-mass- damper subsystems integrated at separated locations along the beam to act as vibration absorbers. For a unit cell of an infinite metamaterial beam, governing equations are derived using the extended Hamilton principle. The existence of stopband is demonstrated using a model based on averaging material properties over a cell length and a model based on finite element modeling and the Bloch-Floquet theory for periodic structures. However, these two idealized models cannot be used for finite beams and/or elastic waves having short wavelengths. For finite metamaterial beams, a linear finite element method is used for detailed modeling and analysis. Both translational and rotational absorbers are considered. Because results show that rotational absorbers are not efficient, only translational absorbers are recommended for practical designs. The concepts of negative effective mass and stiffness and how the spring-mass-damper subsystems create a stopband are explained in detail. Numerical simulations reveal that the actual working mechanism of the proposed metamaterial beam is based on the concept of conventional mechanical vibration absorbers. It uses the incoming elastic wave in the beam to resonate the integrated spring-mass-damper absorbers to vibrate in their optical mode at frequencies close to but above their local resonance frequencies to create shear forces and bending moments to straighten the beam and stop the wave propagation. This concept can be easily extended to design a broadband absorber that works for elastic waves of short and long wavelengths. Numerical examples validate the concept and show that, for high-frequency waves, the structure’s boundary conditions do not have significant influence on the absorbers’ function. However, for absorption of low-frequency waves, the boundary conditions and resonant modes of the structure need to be considered in the design. With appropriate design calculations, finite discrete spring-mass- damper absorbers can be used, and hence expensive micro- or nano-manufacturing techniques are not needed for design and manufacturing of such metamaterial beams for broadband vibration absorption/isolation.
Mutagenesis and functional analysis of the Escherichia coli tRNA(1Leu) promoter.

Summary The leuV promoter which produces tRNALeu1 in Escherichia coli has been extensively mutagenized in order to determine the effects of altered sequences on promoter efficiency (strength) and on growth-rate-dependent regulation (GDR). Each mutant promoter was ligated with a β-galactosidase reporter gene into the chromosome of a host cell by phage lambda lysogenization. Reporter gene activities were measured for cells growing in selected media at various growth rates. Sequences which flank the −10 consensus region, when altered, caused remarkable up-promoter effects, increasing efficiency in some cases almost 10-fold. One up mutation which had five successive T residues in the‘discriminator’region completely abolished GDR, whereas several mutations with single base changes in the discriminator had little or no effect on GDR. Another mutation which changed one base in the −35 region to bring it to consensus increased promoter strength 18-fold and sharply reduced GDR. Chimaeric promoters in which segments of leuV were replaced by segments of the his operon showed that only when the discriminator of leuV is replaced by the his discriminator was GDR-disturbed. AM upstream sequences which were replaced by his sequences had little effect on GDR. Overall, there appeared to be little correlation between promoter efficiency and GDR.
Blending of human and obstacle avoidance control for a high speed mobile robot

Humans remain in the loop in teleoperation because they have some knowledge that the robot they are controlling does not. At the same time teleoperated robots can be programmed to be very good at many tasks, such as avoiding obstacles. Therefore, sharing control between a human and semi-autonomous behaviors on a robot has great potential. This paper presents a model predictive control (MPC) shared control framework for blending human inputs with autonomous behavior inputs. This work adds consideration of how the human input differs from that of an autonomous controller in addition to threat of collision. The framework is applied to a high speed differential drive robot moving through an obstacle field. Preliminary tests by the authors compared the MPC shared control framework to switching obstacle avoidance on/off and the proposed MPC shared control gives the human up to 26% more control with a 35% reduction in collision penalty. Compared to pure human control, MPC shared control demonstrated a 66% reduction in collision penalty. Results show promise for increased user control with better performance.
The investigation of transport properties of mesoscopic graphite in high magnetic field

Abstract The electrical transport properties of mesoscopic graphite have been investigated in a gate voltage configuration. Few layer graphene structures made from Kish graphite exhibit Shubnikov-de Haas (SdH) oscillations in magnetic fields up to 33 T, with a strong gate voltage dependence. A two band model can be used to explain the linear dependence of the SdH frequency on the gate voltage. The temperature dependence of the SdH oscillation amplitude allows the determination of the effective masses of the carriers, which remain comparable between mesoscopic and bulk graphite samples. However, mesoscopic graphite thinner than 130 nm does not exhibit the field induced charge density wave transition seen in bulk samples above 25 T at low temperatures.
Response Surface Methodology Applied to Toll Plaza Design for the Transition to Electronic Toll Collection

This paper describes experiments in which a simulation model of a typical toll plaza with varying mixes of vehicle types and tollbooth allocations was used to aid in the design of automated toll collection toll booths. Data for four output measures were derived from the experiments. These include: vehicle volume, average queue length average waiting time, and tollbooth utilization. In order to fit response surfaces for each measure, multiple linear regression analysis was employed. The response surfaces were able to provide the optimum tollbooth allocation. The paper describes how two decision rules were evaluated for their ability in specifying near-optimum tollbooth allocations for varying mixes of vehicle types using vehicle volume as the output measure.
Composition of steam in the system NaCl-KCl-H2O-quartz at 600°C

Abstract In the system NaCl-KCl-H 2 O, with and without α-quartz present, steam was equilibrated in a large-volume reaction vessel with brine and/or precipitated salt at 600°C and pressures ranging from about 100 to 0.4 MPa. Episodically, steam was extracted for chemical analysis, accompanied by a decrease in pressure within the reaction vessel. In the absence of precipitated salt, within the analytical uncertainty stoichiometric quantities of Cl and total alkali, metals (Na + K) dissolve in steam coexisting with chloriderich brine. In contrast, in the presence of precipitated salt (in our experiments halite with some KCl in solid solution), significant excess chloride as associated hydrogen chloride (HCl 0 °) dissolves in steam. The HCl 0 is generated by the reaction of steam with solid NaCl(s), producing solid NaOH(s) that diffuses into halite, forming a solid solution. In our quasistatic experiments, compared to dynamic flow-through experiments of others, higher initial ratios of H 2 O/NaCl have apparently resulted in higher model fractions of NaOH(s) in solid solution in halite. This, in turn, resulted in incrementally higher concentrations of associated NaOH o dissolved in steam. Addition of quartz to the system NaCl + KC1 + H 2 O resulted in an order of magnitude increase in the concentration of HCl 0 dissolved in steam, apparently as a consequence of the formation of sodium disilicate by reaction of silica with NaOH(s). The measured dissolved silica in steam saturated with alkali halides at 600°C in the pressure range 7–70 MPa agrees nicely with calculated values of the solubility of α-quartz obtained using the equation of Fournier and Potter (1982), corrected for dissolved salt by the method of fournier (1983). Na K ratios in steam at 600°C tend to be slightly greater than in coexisting brine. When precipitated halite is present, larger mole fractions of NaOH(s) in solid solution in that halite apparently result in even larger Na K ratios in coexisting steam. Precipitation of more halite as a consequence of repeated depressurization episodes results in decreased Na K ratios in both the brine and coexisting steam phases, indicating that the lower pressures begin to favor K over Na in the vapor. When steam is in contact with precipitated salts in the absence of brine, the Na K ratio in the steam is less than that of the bulk composition of the salt-H 2 O system.
Combining alprazolam with systematic desensitization therapy for dental injection phobia

To determine whether a benzodiazepine facilitates systematic desensitization, 144 subjects with dental injection phobia received systematic desensitization in combination with placebo or one of two doses of alprazolam (0.5mg or 0.75mg). Systematic desensitization therapy included computer-controlled presentation of digitized video segments followed by in vivo exposure segments, culminating in an actual dental injection. Subjects advanced to the next hierarchy segment when low anxiety was reported during a segment. Alprazolam and placebo groups progressed at the same rate. The 0.75mg group had elevated heart rates while watching video segments compared with placebo. In a subsequent behavioral avoidance test (during which subjects were randomized to a new drug condition), there was no indication that state-dependent learning had occurred. Dental fear was reduced similarly in all groups for 1 year after study completion. No advantage was found to combining alprazolam with systematic desensitization for dental injection phobia.
Derivatives of 17a-Aza-D-homo-5-androsten-3β-ol

The synthesis of several types of N-substituted derivatives of 17a-aza-D-homo-5-androsten-3β-ol as potential antimicrobial agents is reported. Methyl and propyl groups were added by reductive alkylation, and β-dialkylaminoethyl and γ-dialkylaminopropyl groups were introduced by the reaction of dimethylamine or piperidine with the appropriate 17a-(ω-chloroacyl) derivative of VI. None of these derivatives exhibited significant antibacterial or antifungal activity.
Production and standing crop patterns of giant cutgrass (Zizaniopsis miliacea) in a freshwater tidal marsh.

Growth cycles and production of aboveground and belowground giant cutgrass (Zizaniopsis miliacea (Michx.) Doell and Asch.) were studied in a freshwater tidal marsh along the lower Savannah River near Savannah, Georgia, USA. Minimum aboveground live standing crop (142 g/m2) occurred in March with a steady increase thereafter to an October maximum (1,039 g/m2) followed by a rapid decline. Giant cutgrass aboveground net primary production was approximately 1,530 g/m2/yr. Rhizomes (358 g/m2/yr) and roots (160 g/m2/yr) yielded an annual belowground production of 518 g/m2/yr. Total above and belowground annual net production was estimated at 2,048 g/m2/yr.
Demagnetizing fields in the de Haas-van Alphen effect

A description of magnetic interaction, including demagnetizing effects and the vector nature of the magnetization, is presented. Demagnetizing factors appropriate for the second-order approximation for cubic and cylindrical sample shapes are explicitly calculated. A technique for measuring absolute amplitudes based on the weak interaction of two frequencies is proposed.
Retinoic Acid Is a Negative Regulator of the Neuropeptide Y/Peptide YY Y1 Receptor Gene in SK-N-MC Cells

Abstract: To identify effectors of neuropeptide Y Y1 receptor gene expression predicted by putative regulatory elements in its 5′ flanking region, we examined the effects of several transcriptionally active agents on Y1 receptor mRNA levels and 125I-peptide YY binding capacity in SK-N-MC cells. Phorbol ester caused a rapid, transient 2.6-fold increase in Y1R mRNA levels. However, all trans-retinoic acid caused a rapid, sustained decrease in Y1 receptor mRNA levels (to 25% of control). Cycloheximide pretreatment did not attenuate the maximal inhibitory effect of retinoic acid, but it prolonged the time to achieve maximal efficacy. The retinoic acid effect was secondary to both a significant decrease in Y1 receptor mRNA stability and a decreased Y1 receptor gene transcription rate. Y1 receptor binding capacity was also significantly decreased after retinoic acid treatment (368 ± 25 vs. 496 ± 28 fmol/mg of protein for control). These data support a role for retinoic acid as an important agent regulating Y1 receptor gene expression and mediating Y1 receptor down-regulation.
The Orbiting Astronomical Observatory

OAO-Copernicus, launched August 21, 1972, is in its third year of successful operation. Its contributions to scientific knowledge are contained in over 37 scientific papers. Princeton University Observatory has expanded the Guest Investigator Program to include 56 programs by a total of 66 astronomers from 23 countries. Observing time is currently scheduled for twelve months in advance. The engineering features of the Perkin-Elmer-built telescope are surveyed in this paper. A digest of the scientific results and a bibliography of OAO-C related papers is given, and the nature of the investigations planned at the time of writing (September 1974) is summarized.
The role of global cities in land grabs

Key trends link a globally connected urban archipelago and its hinterlands, warranting new studies of power in its most contemporary forms. This article locates land power and where that power is exercised – looking at the burgeoning global land rush from the perspective of cities. Urbanisation continues to drive vast political transitions, uprooting longstanding agrarian modes of living while creating myriad inequalities within cities. Are the world’s most powerful agglomerations active agents in this transformation? Answering affirmatively, the article reframes urbanisation as a vast, global geopolitical transfer of power from rural to urban. Leading global cities like New York, London, Hong Kong, Chicago and Singapore are not merely impressive collections of factor endowments. They are also sites of concentrated power with coercive influences beyond municipal boundaries. The article asks how cities project power in the contemporary global system. Juxtaposing data on global connectivity with the locatio...
Picosecond triplet state dynamics and photodissociation in 2- and 9-iodoanthracene

Abstract Picosecond-resolved transient absorption spectra of iodoanthracenes excited in the S1 manifold with about 3000 cm−1 excess energy, combined with earlier fluorescence studies and analyses of photoproducts from the 366 nm dissociation of the CI bond in benzene and cyclohexane solution, give kinetic evidence for the specific intersystem crossing (ISC) and internal conversion (IC) processes which proceed and compete with photodissociation. Since ISC is heavy atom accelerated to the picosecond domain in iodoanthracenes, intramanifold vibrational relaxation as well as triplet-triplet IC can be monitored with approximately 10 ps resolution. The vibrationless T1 state at about 12 000 cm−1 lies below the energy threshold for dissociation so that the quantum efficiency for CI homolysis is diminished by triplettriplet IC processes leading to T1. 354 nm excitation of 9-iodoanthracene in cyclohexane is followed by rapid vibrational thermalization within the S1 manifold prior to thermally activated ISC to a triplet state Tn of higher energy than S1. In a subsequent decay scenario consistent with our 432 nm Tn←T1 transient absorption rise time and T1 formation quantum yield, Tn branches into IC (ultimately leading to a long-lived T1 state) and photodissociation into R· + I(2P 3 2 ) with efficiencies of about 0.2 and 0.8 respectively. The T1 formation rise time of about 50 ps matches the S1→S0 fluorescence lifetime within experimental scatter for 9-iodoanthracene in cyclohexane at about 25°C, implying a non-radiative decay rate of greater than about 1011 s−1 for Tn in our kinetic model.
Long-Range Proton-Nitrogen Spin Coupling Constants via Polarization-Enhanced Two-Dimensional 15N NMR

Presentation d'une nouvelle methode RMN de transformee de Fourier a deux dimensions pour l'observation et l'attribution des constantes de couplage 15 N- 1 H par une methode selective
Effects of magnetic clouds on the occurrence of geomagnetic storms: The first 4 years of Wind

[1] We investigate geomagnetic activity associated with magnetic clouds as well as some aspects of the clouds' magnetic field structure (e.g., magnetic field distributions of the clouds). Thirty-four magnetic cloud events observed by Wind over the years 1995–1998 are investigated in this study. Magnetic clouds are a principal source of strong, long-lasting, interplanetary, negative Bz fields (in solar magnetospheric coordinates) and hence are a major source of geomagnetic activity (Dst < −50 nT). The region just upstream of a cloud may be a significant source of southward fields instead of, or as well as, the cloud itself. We call this upstream region a “sheath” if it is bounded by a shock (or a pressure pulse) and the cloud. This study helps to identify the major sources (regions of southward Bz following shock passages or within the magnetic clouds) that are most dominant in the generation of geomagnetic storms. It is found that a geomagnetic storm can be induced by (1) a sheath, (2) the leading (i.e., front part) region of a cloud, (3) the trailing part of a cloud, and (4) both sheath and cloud regions. (Because of this complexity a storm with a multistep main phase can occur.) The related occurrence percentages of storms were 17.6% (six events), 44.1% (15 events), 5.9% (two events), and 20.6% (seven events), and the averaged storm intensities (minimum Dst) were −60, −85, −92, and −58 nT, respectively. For the remaining four events (11.8%), there were no storms. The occurrence timing of storm intensity is highly correlated with the occurrence timing of minimum Bz (maximum VBs or ϵ) for a magnetic cloud with the field rotating from southward to northward.
Distributive Effect of State Subsidy to Undergraduate Education: The Case of Illinois.

Abstract An assessment is made of the distributive effects of state subsidies to undergraduate education in public universities and community colleges in Illinois during 1989. The main finding is that the existing system of public subsidy to undergraduate education favors lower-income and middle-income groups. Public subsidies lead to redistribution of income from higher-income to lower-income and middle-income families, with the most significant transfer being from the highest-income group to families with income of less than $40 000 per year. A comparison of the patterns for universities and community colleges indicates that middle-income groups are the major beneficiaries of community colleges; the net transfer from the highest-income group is larger, and the net gain of the poorest group is smaller, in community colleges than in universities. [JEL I22, H7]
Probabilistic search optimization and mission assignment for heterogeneous autonomous agents

This paper presents an algorithmic framework for conducting search and identification missions using multiple heterogeneous agents. Dynamic objects of type “neutral” or “target” move through a discretized environment. Probabilistic representation of the current level of situational awareness - knowledge or belief of object locations and identities - is updated with imperfect observations. Optimization of search is formulated as a mixed-integer program to maximize the expected number of targets found and solved efficiently in a receding horizon approach. The search effort is conducted in tandem with object identification and target interception tasks, and a method for assignment of these missions among agents is developed. The proposed framework is demonstrated in simulation studies, and an implementation of its decision support capabilities in a recent field experiment is reported.