cssi/SciSciGPT-SciSciNet huggingface dataset:
“Measure Your Gradient”: A New Way to Measure Gradients in High Performance Liquid Chromatography by Mass Spectrometric or Absorbance Detection

The gradient produced by an HPLC is never the same as the one it is programmed to produce, but non-idealities in the gradient can be taken into account if they are measured. Such measurements are routine, yet only one general approach has been described to make them: both HPLC solvents are replaced with water, solvent B is spiked with 0.1% acetone, and the gradient is measured by UV absorbance. Despite the widespread use of this procedure, we found a number of problems and complications with it, mostly stemming from the fact that it measures the gradient under abnormal conditions (e.g. both solvents are water). It is also generally not amenable to MS detection, leaving those with only an MS detector no way to accurately measure their gradients. We describe a new approach called "Measure Your Gradient" that potentially solves these problems. One runs a test mixture containing 20 standards on a standard stationary phase and enters their gradient retention times into open-source software available at www.measureyourgradient.org. The software uses the retention times to back-calculate the gradient that was truly produced by the HPLC. Here we present a preliminary investigation of the new approach. We found that gradients measured this way are comparable to those measured by a more accurate, albeit impractical, version of the conventional approach. The new procedure worked with different gradients, flow rates, column lengths, inner diameters, on two different HPLCs, and with six different batches of the standard stationary phase.
Service and its association with matching into a primary care residency

BACKGROUND AND OBJECTIVES There is a shortfall in the primary care workforce, and an effort is needed in learning more about what motivates students to work as generalists. There is enthusiasm about service as a potential motivator. The objective is to determine whether there is an association between high participation in service and selection of a primary care residency. METHODS This is a retrospective cohort analysis. The service award was used to delineate two groups, recipients and non-recipients, with the recipients considered high service participators. This was associated with residency match data using test of proportions to examine relationships between service and selection of a primary care residency and other secondary factors. RESULTS Of award recipients, 57.3% matched in primary care, compared to 52.8%, though this did not reach statistical significance. Service was linked with induction into Alpha Omega Alpha honor society (23.3% versus 14.6%) and induction into the Gold Humanism Honor Society (22.6%. versus 10.4%), with statistical significance. CONCLUSION This was an unsuccessful attempt to find a link between service and a primary care career choice, though there is a trend in the direction. The association with induction into the humanism honor society suggests that service is linked with development and/or retention of positively viewed qualities in medical students.
MARKET POWER AND HOSPITAL PRICING : ARE NONPROFITS DIFFERENT?

ABSTRACT: Dramatic changes in hospitals’ operating environments are leading to major restructuring of hospital organizations. Hospital mergers and acquisitions are increasing each year, and convers...
The improving prospects for yield increase by genetic engineering in antibiotic-producing Streptomycetes.

Molecular genetics has spawned a dramatic expansion of the biotechnology industry in the direction of the products of single genes. On the other hand, antibiotics—some of the classical products of biotechnology—result from the concerted action of many genes, and it is therefore less straightforward to apply the new techniques to antibiotic production. Studies of cloned genes for antibiotic biosynthesis are now providing information that should allow the application of a combination of traditional and recombinant DNA methodology to the improvement of yield in antibiotic-producing Streptomyces species.
Development and Implementation of Shape Comparison of 3D CAD Models

With the advancements of 3D modeling software, the use of CAD in design has become a standard practice. In recent years development in computer hardware and improvements in user friendliness of the CAD software has allowed designers to quickly and easily modify the CAD models. This modification capability allows CAD to be an integral part of the design process. Due to the increase in global competition, companies have become increasingly interested in fast and efficient design processes. One way to achieve improved efficiency is through better collaboration among designers working in common or similar projects and disciplines. A large design problem often requires specialized knowledge from several fields. Collaboration among the designers from these fields will ensure efficient design. Interaction among the designers can prevent redesign of similar components/subsystems, which requires the ability to share their designs. With the increase of collaboration, designers can now get access to large databases of 3D CAD models. But the challenge lies in search capabilities to identify common models from a large database. These considerations suggest that in the near future a challenge in 3D CAD industry will be how to find models of similar components and products. This paper presents an approach and its implementation to measure the similarity among a number of CAD models. The approach is based on the extraction and organization of information from the CAD models, which is followed by the suitable selection of commonality index and calculation of the commonality among a set of CAD models. A set of Vacuum cleaners are modeled and then compared to demonstrate the application of the approach.Copyright © 2009 by ASME
Generalized Theory of Convective Heat Transfer in a Free-Molecule Flow

The theoretical analysis of convective heat transfer in a freemolecule flow with Maxwellian velocity distribution is generalized by reducing all relationships to a form common to all gases irrespective of their molecular structure. A simplified computingprocedure is set up, and the heat-transfer characteristics of a flat plate, cylinder, and sphere are presented and correlated graphically. A method of applying these results to a cone and to compound shapes is described. NOMENCLATURE cp Cv D E e erfs erfcs F = specific heat capacity at constant pressure, (ft.lbs.)/(lb.sec./ft.)°F„ = specific heat capacity at constant volume, (ft.lbs.)/(lb.sec./ft.)°F. = reference diameter, (ft.) = molecular energy transport rate, (ft.lbs./sec.) = molecular energy transport rate per unit surface area, (ft.lbs./ft.sec.) = base of natural logarithms 2.7183 error function ' dx, (dimensionless) = complementary error functions, 1 — erfs, (dimensionless) = average surface integral defined by Eq. (2.13), if/ erage s h his) f dS, (see Q) = average surface integral defined by Eq. (2.14), : dS, (see Q) -Taw), = heat-transfer coefficient, Q/(TW (ft.lbs./ft.sec. °F.) = modified Bessel function of first kind and zeroth order, / ^ ^ o s ^ d , (dimensionless) Jo Ii(s) = modified Bessel function of first kind and first order, -s cos 0 c o s ^ ^ (dimensionless) ierfcs = integral of the complementary error function, erf ex dx, (dimensionless) "Jo i: J k M N Nu = number of degrees of freedom, (dimensionless) = Boltzman constant 5.66.10~ 4 (ft.lb./molecule°F.) = Mach Number (dimensionless) = number of molecules per unit volume (molecules/ft.) = Nusset Number JID/K (dimensionless) Received May 21, 1952. * This work was done as part of an Office of Naval Research contract with the Department of Engineering, University of California at Berkeley. f Assistant Professor of Mechanical Engineering. Pr Q
The modeling of pool profiles, temperature profiles and velocity fields in ESR systems

Through the simultaneous statement of Maxwell’s equations, the turbulent Navier-Stokes equations and the differential thermal energy balance equations a mathematical model has been developed to represent the pool profiles, the velocity fields and the temperature profiles in an ESR system. The major advance over earlier modeling efforts is the fact that the model is capable of predicting the pool profiles from first principles. The theoretically predicted pool profiles and temperature fields were found to be in reasonable agreement with experimental measurements reported by Mellberg for a laboratory scale system. The model is used to investigate the interdependence of key process parameters, with the power input, fill ratio, amount of slag used and the position of the electrode as the independent variables and the casting rate, pool depth, velocity and temperature fields as the dependent variables.
NF-κB-Mediated Regulation of Osteoclastogenesis.

Osteoclasts are multinucleated cells formed mainly on bone surfaces in response to cytokines by fusion of bone marrow-derived myeloid lineage precursors that circulate in the blood. Major advances in understanding of the molecular mechanisms regulating osteoclast formation and functions have been made in the past 20 years since the discovery that their formation requires nuclear factor-kappa B (NF-κB) signaling and that this is activated in response to the essential osteoclastogenic cytokine, receptor activator of NF-κB ligand (RANKL), which also controls osteoclast activation to resorb (degrade) bone. These studies have revealed that RANKL and some pro-inflammatory cytokines, including tumor necrosis factor, activate NF-κB and downstream signaling, including c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), and inhibition of repressors of NFATc1 signaling, to positively regulate osteoclast formation and functions. However, these cytokines also activate NF-κB signaling that can limit osteoclast formation through the NF-κB signaling proteins, TRAF3 and p100, and the suppressors of c-Fos/NFATc1 signaling, IRF8, and RBP-J. This paper reviews current understanding of how NF-κB signaling is involved in the positive and negative regulation of cytokine-mediated osteoclast formation and activation.
Public Private Not-for-profit Partnerships: Delivering Public Services to Developing Countries☆

Abstract International organizations, Non-Governmental Organizations (NGOs), governments and the private sector have not found a long-term solution to public service delivery. (1) (2) The paper establishes a framework that makes Public Private Partnerships (PPP) more accessible to developing countries. A partnership between government, NGOs, and the private sector in order to allocate risk to the one who is able to avoid or mitigate them and responsibilities to the most capable in order to have a sustainable service delivery to the beneficiaries in an financially sound way.
Hyperfine fields in ordered lithium ferrite

Abstract The experimental 57 Fe spectra of Doroshev et al. are explained in terms of dipole-like fields.
Phonon renormalization and Raman spectral evolution through amorphous to crystalline transitions in Sb2Te3 thin films

A symmetry specific phonon mode renormalization is observed across an amorphous to crystalline phase transformation in thin films of the topological material Sb2Te3 using Raman spectroscopy. We present evidence for local crystalline symmetry in the amorphous state, eventhough, the q = 0 Raman selection rule is broken due to strong structural disorder. At crystallization, the in-plane polarized (Eg2) mode abruptly sharpens while the out-of-plane polarized (A1g) modes are only weakly effected. This effect unique to the Eg symmetry is exceptional considering that polarized spectra and comparison of the single phonon density of states between the amorphous and crystalline phases suggest that short range order of the amorphous phase is, on the average, similar to that of the crystalline material while electrical transport measurements reveal a sharp insulator-to-metal transition. Our findings point to the important role of anisotropic disorder affecting potential applications of topological and phase-change based electronics.
On the measurements of the radial temperature distribution in an extruder channel

In single-screw extrusion it is not unusual to encounter large temperature variations within the screw channel, especially at high pumping rates. These temperature variations result in nonhomogeneities that affect the quality of the final product. Although there have been numerous efforts aiming at the simulation of the flow in the channel of a single-screw extruder, and the prediction of important flow quantities, there is hardly any published work in which the temperature distribution in the screw channel was actually measured. Such measurements, if available, would provide data by which computer simulations could be validated. In the present study, a fast-response, cam-driven thermocouple system was developed and used to measure the radial temperature distribution in the screw channel. The measurements are carried out on a well-controlled, custom-built, single-screw extruder. Temperature profiles in the centerline of the screw channel were obtained for various operating conditions of the machine. The data obtained revealed interesting features of the flow as well as the dominant heat transfer mechanisms. The system as developed here can be improved to accommodate larger industrial applications. © 1994 John Wiley & Sons, Inc.
Biochemical characterization of a mutant recBCD enzyme, the recB2109CD enzyme, which lacks χ-specific, but not non-specific, nuclease activity

Abstract RecBCD enzyme of Escherichia coli is a DNA helicase which also possesses ATP-dependent nuclease activities. We have purified a mutant recBCD enzyme, designated recB2109CD enzyme, and have examined the nuclease activities of this protein in vitro to determine whether any alteration in these activities is responsible for the recombination-deficient phenotype of the recB2109 strain. The recB2109CD enzyme possesses all of the non-specific nuclease activities (dsDNA exonuclease and ssDNA exo- and endonuclease) associated with wild-type recBCD enzyme although they are reduced ∼ 2 to 3-fold relative to the wild-type enzyme. The ATP -dependent dsDNA exonuclease activity of recB2109CD enzyme requires significantly higher ATP concentrations for optimal activity when compared to the wild-type enzyme. The ATP-independent ssDNA endonuclease activity of the two enzymes is similar, but the ATP-stimulated ssDNA endonuclease and ATP-dependent ssDNA exonuclease activities of the mutant enzyme are reduced relative to those of wild-type recBCD enzyme. Despite its ability to degrade linear dsDNA non-specifically, recB2109CD enzyme lacks sequence-specific nicking activity at χ sites, which are hotspots for genetic recombination. Since this interaction with χ significantly attenuates the non-specific dsDNA exonuclease activity of wild-type recBCD enzyme, these results suggest that the non-specific dsDNA exonuclease activity of the mutant enzyme cannot be attenuated, with the consequence that a DNA substrate which is suitable for recombination is not produced.
Mentoring At‐Risk Youth in Schools: Can Small Doses Make a Big Change?

The impact of length of the match and age of the child was evaluated in a site‐based mentoring program. At‐risk children ranging in age from 7 to 12 were matched with an adult mentor and met approximately once a week at school during the academic year. Results indicated that neither the length of the match nor the age of the child influenced the impact of mentoring. Pre/post analyses of several psychological variables indicated that children liked school better (p = .002, η2 = .11), behaved better in the classroom (p = .021, η2 = .07), got along better with their peers (p < .001, η2 = .25), and had increased self‐esteem (p < .001, η2 = .14) at the end of mentoring. No improvement in grades was found. The results indicate that matches that are relatively short in duration can have an important impact on at‐risk children. In addition, the results indicate that at‐risk children who are both younger and older can have positive outcomes from mentoring.
Measurement of optical fiber diameter using the fast Fourier transform

The variation of the fringe spacing of the far zone scattered intensity of an illuminated optical fiber has been plotted vs the scattering angle, theoretically and experimentally. A method for measuring fiber diameters by taking the Fourier transform of the scattering intensity is described. Theoretical and experimental results have been compared at various angles for different fiber diameters.
PROTEUS: network performance forecast for real-time, interactive mobile applications

Real-time communication (RTC) applications such as VoIP, video conferencing, and online gaming are flourishing. To adapt and deliver good performance, these applications require accurate estimations of short-term network performance metrics, e.g., loss rate, one-way delay, and throughput. However, the wide variation in mobile cellular network performance makes running RTC applications on these networks problematic. To address this issue, various performance adaptation techniques have been proposed, but one common problem of such techniques is that they only adjust application behavior reactively after performance degradation is visible. Thus, proactive adaptation based on accurate short-term, fine-grained network performance prediction can be a preferred alternative that benefits RTC applications. In this study, we show that forecasting the short-term performance in cellular networks is possible in part due to the channel estimation scheme on the device and the radio resource scheduling algorithm at the base station. We develop a system interface called PROTEUS, which passively collects current network performance, such as throughput, loss, and one-way delay, and then uses regression trees to forecast future network performance. PROTEUS successfully predicts the occurrence of packet loss within a 0.5s time window for 98% of the time windows and the occurrence of long one-way delay for 97% of the time windows. We also demonstrate how PROTEUS can be integrated with RTC applications to significantly improve the perceptual quality. In particular, we increase the peak signal-to-noise ratio of a video conferencing application by up to 15dB and reduce the perceptual delay in a gaming application by up to 4s.
Source routing in computer networks

As plans for network interconnection develop, the problems of internet routing and addressing become increasingly important. In one popular model of internet addressing, a hierarchical form of network and local (within network) address is used, with the source providing only the destination address while the intermediate network(s) and/or Gateways between networks take care of routing packets to that destination by various paths. This and related techniques requiring some form of routing table and knowledge at intermediate nodes are more fully discussed in [1,2,3].This paper considers another technique for internet routing in which the source of internet packets specifies the complete internet route. When the entire route accompanies each internet packet, no routing decisions or tables are required at Gateways, but the packet format is complicated and overhead increases. In particular, the packet must carry a varying number of intermediate addresses depending on the path and destination [4]. This overhead may be reduced by setting up a fixed route with connection tables [1] when a connection is established.
Site-directed mutations in the transmembrane domain M3 of human connexin37 alter channel conductance and gating.

Abstract Connexin37 (Cx37) is expressed principally in endothelial cells. We have introduced individual point mutations (Cx37-V156D or Cx37-K162E) in the putative pore lining segment M3 of a polymorphic human Cx37 (Cx37-S319) and expressed them in N2A and RIN cells. RT-PCR and immunofluorescence microscopy were used to confirm the expression of the proteins. Stably transfected cells were subjected to electrophysiological studies. Experiments were performed on cell pairs using the dual whole cell patch-clamp method. Single channel records showed that both mutants display a variety of conductive states (Cx37-V156D, 47-250 pS; Cx37-K162E, 58-342 pS) in contrast to the typical high conductance of 340–375 pS and subconductive state of 60–80 pS reported for Cx37-S319. Analysis of the macroscopic data for Cx37-K162E revealed a broadened Vo indicating the influence of the mutation on voltage gating. Our data indicate that substitution of a conserved residue with a charged residue could cause changes in the main state and/or in the size of the pore. It is possible that these particular residues in the M3 domain interact electrostatistically with several of the other domains in the Cx37 protein.
Looking around: 35 years of oculomotor modeling

Eye movements have attracted an unusually large number of researchers from many disparate fields, especially over the past 35 years. The lure of this system stemmed from its apparent simplicity of description, measurement, and analysis, as well as the promise of providing a "window in the mind." Investigators in areas ranging from biological control systems and neurological diagnosis to applications in advertising and flight simulation expected eye movements to provide clear indicators of what the sensory-motor system was accomplishing and what the brain found to be of interest. The parallels between compensatory eye movements and perception of spatial orientation have been a subject for active study in visual-vestibular interaction, where substantial knowledge has accumulated through experiments largely guided by the challenge of proving or disproving model predictions. Even though oculomotor control has arguably benefited more from systems theory than any other branch of motor control, many of the original goals remain largely unfulfilled. This paper considers some of the promising potential benefits of eye movement research and compares accomplishments with anticipated results. Four topics are considered in greater detail: (i) the definition of oculomotor system input and output, (ii) optimization of the eye movement system, (iii) the relationship between compensatory eye movements and spatial orientation through the "internal model," and (iv) the significance of eye movements as measured in (outer) space.
Predictions of MSMA Response Under Bi-Axial Mechanical Loading

Magnetic shape memory alloys (MSMAs) are materials commonly used for actuation, sensing, and/or power harvesting applications. To date, these applications have primarily been explored under a magnetic field and/or a compressive stress, with the stress and the field acting along directions perpendicular to each other. However, other applications may be envisioned, and existing applications may be optimized, with alternate load configurations. The alternate load configuration to be explored in this work is the application of bi-axial compressive stresses. This configuration could be used in actuation or power harvesting applications. A constitutive model, proposed by LaMaster et al. [1], is simplified and used to predict the response of the material under bi-axial compressive stresses. Model predictions are compared with experimental data from the literature.Copyright © 2014 by ASME
Self-regulation strategies used by student musicians during music practice

Individual music practice is a vital aspect of a student's development as a musician. Research indicates that expert music performers utilise substantial planning and a systematic approach to practice sessions, including problem identification, strategy planning and evaluation (Hallam 2001b), all of which are components of self-regulated thinking. The purpose of this study was to discover what self-regulating strategies adolescent instrumental musicians’ use during music practice. Sixteen middle school instrumental musicians were videotaped as they practiced a new piece of music. Immediately following the practice session, the student and researcher viewed the videotape of the session, and the student explained the strategies used during practice. Examination of the concurrent verbal report and music practice data revealed that repetition was referred to or used more frequently than other strategies. It is hoped that this study will aid in a better understanding of the self-regulation capabilities of stud...
Problem-Solving Skills, Locus of Control, and the Contraceptive Effectiveness of Young Women.

It was proposed that the lack of insight into the risk-taking behavior of many sexually active women who do not want to get pregnant may reflect the lack of an adequate framework from which to investigate the problem. The purpose of this study was to examine the relationships between contraceptive effectiveness and several cognitive factors. The sample consisted of 155 single women, 15.3-25.7 years of age, from a Planned Parenthood clinic and an abortion clinic. Contraceptive effectiveness, operationally defined as the number of unplanned pregnancies in a woman's history, was significantly and negatively related to means-ends problem-solving ability and a belief in internal control and significantly and positively related to a belief in chance control. It was suggested that these results support the utility of a cognitive, problem-solving approach to the study of contraceptive behavior.
Reversible and irreversible effects of alkaline pH on Photosystem II electron-transfer reactions.

Abstract Incubation of highly active, O 2 -evolving PS II preparations at alkaline pH inhibits donor side electron-transfer reactions in two distinct fashions, one reversible the other irreversible. In both cases, O 2 evolution is inhibited, with concomitant loss of the light-induced multiline and g = 4.1 EPR signals and an increased steady-state level of EPR Signal II induced by continuous illumination. However, the inhibition that is observed between pH 7.0 and 8.0 is readily reversible by resuspension at low pH, while above pH 8.0 the effect is irreversible. In addition, under repetitive flash conditions the ms decay kinetics remains largely unchanged at pH ≤ 8.0 but shows about a 2-fold increase in amplitude and is slowed at pH above 8.0. The irreversible component of inhibition most likely can be attributed to the loss of Mn and the 16, 24 and 33 kDa proteins. The reversible component may be mediated by displacement of Cl − from an anion-binding site by OH − or by titration of ionizable groups on the protein(s) associated with water-splitting. We propose that the reversible inhibition blocks electron transfer between the O 2 -evolving complex and an intermediate which serves as the direct donor to Signal II, while the irreversible inhibition blocks the reduction of Signal II by this intermediate donor species.
Locating an obnoxious facility

Abstract We demonstrate that a formulation of the obnoxious single facility location problem is equivalent to the complex moment problem. The equivalence is understood in the sense that the critical points of the potential function defining the location problem are equal to the zeros of the function defining the complex moment problem.
Assessment of the technical performance of the flexible 19-gauge EUS-FNA needle

Background A needle made of nitinol has been developed with enhanced flexibility to overcome the limitations of the currently available 19-G EUS-FNA needles. Objective Evaluate the ability to perform transduodenal FNAs, procure histologic specimens, and undertake therapeutic interventions using the flexible 19-G needle. Design Prospective cohort study. Setting Tertiary-care academic medical center. Patients Consecutive patients with subepithelial masses, pancreatic head or uncinate lesions, or lesions adjacent to the pancreatic head, and patients undergoing therapeutic intervention. Interventions Perform tissue acquisition and interventions with the flexible 19-G FNA needle. Main Outcome Measures Evaluate the ability to perform transduodenal passes with the flexible 19-G FNA needle. Also, assess the utility of the needle to yield both cytologic and histologic samples and to perform therapeutic interventions. Results Of the 50 patients enrolled, tissue acquisition was undertaken in 38 and therapeutic intervention in 12. Of 38 patients from whom tissue was procured, 32 tissue samples were from pancreatic head/uncinate or peripancreatic masses and 6 were from subepithelial masses. Tissue acquisition, which included transduodenal passes, was successful and adequate for cytologic assessment in all 38 patients (100%). Satisfactory histologic specimens were procured from 36 of 38 (94.7%) patients. An onsite diagnosis was established in 35 of 38 (92.1%) patients. In 3 patients with indeterminate/suspicious lesions, a definitive diagnosis was established at histology. A mean of 1.45 ± 0.79 passes per patient was performed. All 12 therapeutic interventions were successful (100%) and included pseudocyst drainage in 5, pelvic abscess drainage in 2, fiducial placement in 2, celiac plexus neurolysis in 2, and cholangiogram in 1. Needle dysfunction or procedural complications were not encountered. Limitations Single-center study with limited power. Conclusions Preliminary data suggest that the flexible 19-G needle can be used for procuring cytologic aspirates and histologic specimens and to undertake therapeutic interventions even by the transduodenal route. Confirmatory studies are required in a larger cohort of patients with varied pathologic conditions to validate these findings.
Electric dipole moments of pendular molecules

Abstract External electric fields can halt the rotation of polar molecules and produce pendular states in which the molecular dipole μ is confined to librate over a limited angular range about the space-fixed direction of the external field. The pendular eigenfunctions are hybrids of field-free rotor states, (J,K,M) with indefinite (for K ≠ 0) or alternating (for K = 0) parities; this renders the parity of the hybrid wavefunctions indefinite for any values of the good quantum numbers K or M. As a result, the parity selection rule for the matrix elements of tensor operators in the pendular basis, notably the electric dipole moment, is lifted. We give the expectation values of the space-fixed dipole moment operator and of the orientation cosine of the figure axis and illustrate the lifting with field strength of the parity selection rule for prototype hybrid states of polar molecules. The symmetry properties of the pendular Hamiltonian are used to sort the eigenstates according to the sign of the product of...
Oral histories in meteoritics and planetary science—XXV: Vagn F. Buchwald

Vagn Buchwald (Fig. 1) was born in Copenhagen where he attended school and college. Then after 18 months of military service, he assumed a position at the Technical University of Copenhagen. A few years later, he was presented with a piece of the Cape York meteorite, which led to an interest in iron meteorites. Through a campaign of informed searching, Vagn found the 20 ton Agpalilik meteorite (part of the Cape York shower) on 31st July 1963 and by September 1967 had arranged its transport to Copenhagen. After sorting and describing the Danish collection, which included application of the Fe-Ni-P phase diagram to iron meteorite mineralogy, Vagn was invited to sort and describe other iron meteorite collections. This led to a 7 yr project to write his monumental Handbook of Iron Meteorites. Vagn spent 3 yr in the United States and visited most of the world's museums, the visit to Berlin being especially important since the war had left their iron meteorites in bad condition and without labels. During a further decade or more of iron meteorite research, he documented natural and anthropomorphic alterations experienced by iron meteorites, discovered five new minerals (roaldite, carlsbergite, akaganeite, hibbingite, and arupite); had a mineral (buchwaldite, NaCaPO4) and asteroid (3209 Buchwald 1982 BL1) named after him; and led expeditions to Chile, Namibia, and South Africa in search of iron meteorites and information on them. Vagn then turned his attention to archeological metal artifacts. This work resulted in many papers and culminated in two major books on the subject published in 2005 and 2008, after his retirement in 1998. Vagn Buchwald has received numerous Scandinavian awards and honors, and served as president of the Meteoritical Society in 1981–1982.
IDENTIFICATION OF A MATHEMATICS CORE IN VOCATIONAL PROGRAMS AT 2‐YEAR COLLEGES

Fifty‐seven faculty across 26 vocational program areas at Odessa College in Odessa, Texas, were surveyed during the 1991 fall semester. A core of 38 mathematic competency skills from a list of 70 previously developed mathematic competencies were identified as being necessary for students to be successful in vocational program areas. A comparison of these mathematic competency skills with those reported in a Vernon Regional Junior College study indicated similar results. The 38 mathematic competencies identified in the study were combined into five mathematic areas: whole numbers, fractions, decimals, mixed operations involving converting mixed numbers to decimal fractions and decimal fractions to mixed numbers, and measurement and calculation (metric and English systems). Stephanie Kern (PhD in higher education administration from the University of North Texas) is an associate professor of mathematics at Odessa College. Her specialty is mathematics education. Randall E. Schumacker (PhD in educational psyc...
T cell expansion is regulated by activated Gr-1+ splenocytes

Abstract CD4 + T cell proliferation depends on the balance between NO and extra-cellular superoxide (O 2 − ). By reducing NO bio-availability, O 2 − promotes splenic T cell proliferation and immune response intensity. Here, we show that spleen cells from naive mice produced neither NO nor O 2 − during T cell activation, but Gr-1 + splenocytes from primed mice regulated Ag-specific T cell expansion via production of both molecules. Purified splenic Gr-1 + cells included mostly granulocytes at various stages of maturation, as well as monocytes. Activation or recruitment of regulatory Gr-1 + cells was dependent on immunization with CFA. Importantly, these regulatory cells were not detected in draining lymph nodes. These data suggest that innate Gr-1 + splenic cells regulate adaptive immunity.
Low-intensity limit of the laser cooling of a multistate atom

We adapt an earlier semiclassical theory of laser cooling of an arbitrary multistate atom [J. Javanainen, Phys. Rev. A 44, 5857 (1991)] to the limit of low light intensity. The formal theory is implemented analytically on a computer using mathematica. Expressions of light-pressure force and diffusion are provided for ${\mathit{j}}_{1}$=1/2\ensuremath{\rightarrow}${\mathit{j}}_{2}$=3/2 and ${\mathit{j}}_{1}$=1\ensuremath{\rightarrow}${\mathit{j}}_{2}$=2 atoms in a one-dimensional optical confinement area in which the pair of counterpropagating waves has orthogonal polarizations. In our models the cooling temperature decreases as the level degeneracy increases.
Adolescent drug use in three small rural communities in the Rocky Mountain region.

Anonymous surveys of drug use were administered to eighth- and twelfth-grade students in three small rural communities and one mid-sized community in the Rocky Mountain region. Differences were found between the three small towns in both lifetime prevalence and the frequency of occurrence of different types of drug users, indicating that small rural communities are likely to develop idiosyncratic patterns of drug use. These differences were more evident among eighth-grade than among twelfth-grade students. Minimal differences were found between the combined small community sample and the urban sample. Use by small town youth, for some drugs, may even exceed that of students in urban communities, suggesting that youth from small communities no longer have lower use rates, at least in this region. Differences of use between seniors in the Rocky Mountain region (small town and urban communities combined) and the national senior survey [1] are relatively small, but significant, perhaps reflecting a regional p...
Understanding the complexities of group perception: broadening the domain

Recent developments in the study of group perception have been guided by four concepts: homogeneity, essentialism, agency, and entitativity. Research on these topics has broadened the scope of questions asked, issues studied, and explanatory mechanisms that are important in the perception of groups. This article summarizes each concept, discusses its contribution to understanding group perception, and highlights unresolved questions that need investigation. Possible conceptual interpretations of the relations among these concepts and their relationship to stereotyping are then discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Structure-dependent phytotoxicity of fumonisins and related compounds in a duckweed bioassay

Abstract Fumonisins A1, A2, B2, B2, and B3 are a series of secondary metabolite analogues produced by Fusarium moniliforme. The A series fumonisins differ from B series by possession of a N terminal acetyl group. Hydrolytic removal of the propanetricarboxylic acid moieties from fumonisins B1, and B2 yields the aminoalcohols HB1, and HB2, respectively. AAL-toxin is a chemically related phytotoxin (only one propanetricarboxylic acid) produced by Alternaria alternata. In a duckweed (Lemna pausicostata) bioassay, AAL-toxin and the B series fumonisins at 1,μM caused pronounced cellular leakage of electrolytes and photodegradation of chlorophylls. These four compounds also caused the most marked reductions in duckweed growth. HB1, at 1 μM was a moderate growth inhibitor and caused a low level of cellular leakage. The other compounds were inactive at this concentration. Significant effects on cellular leakage were measured at 0.04 μM for both AAL-toxin and fumonisin B1, the two most active analogues. The propanetricarboxylic acid groups of fumonisins and AAL-toxin are necessary for significant herbicidal activity of this series of compounds, whereas acetylation of the terminal amine group greatly reduces their activity. The structurally related sphingolipids, phytosphingosine and sphingosine, were about two orders of magnitude less phytotoxic than fumonisin B1; however, the phytotoxicity symptoms were similar.
Ginger Compound [6]-Shogaol and Its Cysteine-Conjugated Metabolite (M2) Activate Nrf2 in Colon Epithelial Cells in Vitro and in Vivo

In this study, we identified Nrf2 as a molecular target of [6]-shogaol (6S), a bioactive compound isolated from ginger, in colon epithelial cells in vitro and in vivo. Following 6S treatment of HCT-116 cells, the intracellular GSH/GSSG ratio was initially diminished but was then elevated above the basal level. Intracellular reactive oxygen species (ROS) correlated inversely with the GSH/GSSG ratio. Further analysis using gene microarray showed that 6S upregulated the expression of Nrf2 target genes (AKR1B10, FTL, GGTLA4, and HMOX1) in HCT-116 cells. Western blotting confirmed upregulation, phosphorylation, and nuclear translocation of Nrf2 protein followed by Keap1 decrease and upregulation of Nrf2 target genes (AKR1B10, FTL, GGTLA4, HMOX1, and MT1) and glutathione synthesis genes (GCLC and GCLM). Pretreatment of cells with a specific inhibitor of p38 (SB202190), PI3K (LY294002), or MEK1 (PD098059) attenuated these effects of 6S. Using ultra-high-performance liquid chromatography–tandem mass spectrometry,...
Dynamics and fluctuation spectra of electrostatic resistive interchange turbulence

The saturation mechanism for density and potential fluctuation spectra that evolve from linearly unstable electrostatic resistive interchange modes are investigated using particle simulations. Detailed comparisons of the nonlinear evolution, saturation levels, and resultant spectra between two‐ and three‐dimensional sheared magnetic field configurations are made. Significant differences appear. The single rational surface, quasilinear‐dominated evolution, fluctuation spectrum is adequately described using a density convection model. For the multiple rational surface case, the potential fluctuations are adequately represented by a balance between the nonlinearly modified source (curvature drive) and linear sink (parallel resistive field line diffusion). An accurate description of the density spectrum requires a mode coupling theory based on the two‐point density correlation evolution equation.
The structure of glassy metallic alloys

Abstract It has been found possible to produce relatively stable amorphous metallic solids from many noble or transition metal-metalloid alloys in the vicinity of 80 at. % metal. Detailed consideration is given to a proposed structural model for these glasses. The structural model focuses on the role of composition in these alloys and successfully predicts the composition range for which glasses are most readily obtained. It also agrees well with experimentally determined radial distribution functions and densities and provides an understanding of the origin of the excess entropy of mixing of these alloys in the liquid state.
Temperature gradients and frictional energy dissipation in the sliding of hydroxylated α-alumina surfaces

The dynamics of friction and energy dissipation of a small nanoscale hydroxylated alumina surface sliding across a large identical surface were investigated by molecular dynamics (MD) simulations. The energy released into both the sliding and stationary surfaces and the energy transfer from the sliding interface to the bulk were investigated by monitoring the temperature of the surfaces and their sublayers. Steady state temperature gradients are found for the sublayers of each surface as a result of the balance between the heat released from the sliding friction and heat transfer to the bulk. The MD simulations show periodic friction energy release from the interface to the surfaces, giving rise to periodic changes in the temperature of the surface sublayers. This temperature depends on the sliding velocity. The periodicity in the friction energy release arises from the periodic unit cell structures of the surfaces. Atomic-level vibrational motions and interdigitation of the surface atoms give rise to the frictional energy of the sliding surfaces. Velocity distributions are determined for atoms within different surface layers and they become more Boltzmann-like the further the layers are from the interface and if the sliding is fast and not in the stick–slip regime. Tribological properties for continuous sliding across the same regime of the bottom surface, by using periodic boundary conditions, differ from those for sliding across a large bottom surface.
Group Technology Applications In Material Handling

The selections of material handling equipment for different manufacturing components are largely dependent on the characteristics of the component to be manipulated. The tasks of designing or selecting material handling equipment are usually dependent on the experience of the engineer and the equipment available. In this research, the group technology concept is applied to record and organize the material handling information. Expressions related to material handling, such as the weight, size, configurations of the component, etc., are included in a general purpose group technology classification and coding system. Components can be grouped into part families according to their material handling properties. Material handling equipment can then be designed for a group of components or can be selected based on the similarities of a group of parts. In addition, a multi-objective clustering method, which is based on a goal programming theory, is utilized for more effective information searching. This approach assists the engineer in designing the material handling equipment or selecting the available one. Industrial application shows that this approach reduces the design time cycle for material handling equipment and increases in utilization of the available facilities.
Iontophoretic studies of histamine and histamine antagonists in the feline vestibular nuclei.

Abstract The activity of single neurons in the vestibular neuronal complex of midcollicular decerebrate, decerebellectomized cats were recorded and their responsiveness to iontophoretically applied histamine while 24% were excited by this agent. Neurons exhibiting inhibitory responses were widely distributed throughout the four vestibular nuclei and adjacent reticular formation whereas excitatory responses to histamine were obtained mainly in the region of the lateral vestibular nucleus. The H 2 -receptor blocking agents metiamide and cimetidine were examined as to their actions on spontaneously firing cells and cells affected by histamine. Metiamide was selective in blocking histamine-induced inhibition but not excitation while cimetidine was ineffective in blocking either response. These results suggest that histamine has both inhibitory and excitatory actions on brain stem neurons and metiamide is an effective antagonist of histamine-induced inhibition.
KnowItNow: Fast, Scalable Information Extraction from the Web

Numerous NLP applications rely on search-engine queries, both to extract information from and to compute statistics over the Web corpus. But search engines often limit the number of available queries. As a result, query-intensive NLP applications such as Information Extraction (IE) distribute their query load over several days, making IE a slow, offline process.This paper introduces a novel architecture for IE that obviates queries to commercial search engines. The architecture is embodied in a system called KnowItNow that performs high-precision IE in minutes instead of days. We compare KnowItNow experimentally with the previously-published KnowItAll system, and quantify the tradeoff between recall and speed. KnowItNow's extraction rate is two to three orders of magnitude higher than KnowItAll's.
Facilitating Self-Initiated Proto-Declaratives and Proto-Imperatives in Prelinguistic Children with Developmental Disabilities:

This study tested the effects of 2 prelinguistic communication interventions on generalized use of communication for two major pragmatic functions: proto-imperatives and proto-declaratives. Outcome...
Sinogram resolution recovery using information gained through detector motion

Positron emission tomography (PET), as a biomedical imaging modality, is unique in its ability to provide quantitative information regarding biological function in a living subject. Unfortunately, its use has been hampered by the poor spatial resolution of the images produced, resulting primarily from the relatively large detectors used to acquire the tomographic measurements. In this paper, we show that by applying signal recovery to the data obtained by moving the detection system during the course of the measurement process, dramatic improvement in image quality can be obtained when detector size is, indeed, the factor limiting spatial resolution. The method of projections onto convex sets is used to recover (deblur) the sinogram, from which the image is reconstructed by conventional filtered backprojection. By making use of filtered backprojection in the reconstruction step, the computational burden commonly associated with iterative signal recovery is avoided; the proposed method adds only a few seconds to the total processing time. Simulation results demonstrate that the method is robust to misspecification of the point spread functions of the detection system as well as to the high levels of quantum noise inherent in PET.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The use of electrical current in the treatment of nonunions.

This article reviews the basic electrophysiology of normal and injured bone. Indications and contraindications for the use of electrostimulation in the treatment of fracture nonunions are discussed, as is the instrumentation necessary for this purpose.