cssi/SciSciGPT-SciSciNet huggingface dataset:
Association of a Workplace Sales Ban on Sugar-Sweetened Beverages With Employee Consumption of Sugar-Sweetened Beverages and Health.

Importance Reductions in sugar-sweetened beverage (SSB) intake can improve health, but are difficult for individuals to achieve on their own. Objectives To evaluate whether a workplace SSB sales ban was associated with SSB intake and cardiometabolic health among employees and whether a brief motivational intervention provides added benefits to the sales ban. Design, Setting, and Participants This before-after study and additional randomized trial conducted from July 28, 2015, to October 16, 2016, at a Northern California university and hospital assessed SSB intake, anthropometrics, and cardiometabolic biomarkers among 214 full-time English-speaking employees who were frequent SSB consumers (≥360 mL [≥12 fl oz] per day) before and 10 months after implementation of an SSB sales ban in a large workplace, with half the employees randomized to receive a brief motivational intervention targeting SSB reduction. Interventions The employer stopped selling SSBs in all workplace venues, and half the sample was randomized to receive a brief motivational intervention and the other half was a control group that did not receive the intervention. This intervention was modeled on standard brief motivational interventions for alcohol used in the workplace that promote health knowledge and goal setting. Main Outcomes and Measures Outcomes included changes in SSB intake, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and measures of abdominal adiposity. The primary associations tested were the correlation between changes in SSB intake and changes in HOMA-IR. Results Among the 214 study participants, 124 (57.9%) were women, with a mean (SD) age of 41.2 (11.0) years and a baseline mean (SD) body mass index of 29.4 (6.5). They reported a mean daily intake of 1050 mL (35 fl oz) of SSBs at baseline and 540 mL (18 fl oz) at follow-up—a 510-mL (17–fl oz) (48.6%) decrease (P Conclusions and Relevance This study’s findings suggest that the workplace sales ban was associated with a reduction in SSB intake and a significant reduction in waist circumference among employees within 10 months. The randomized clinical trial portion of this study found that targeting those at high risk with a brief motivational intervention led to additional improvements. Workplace sales bans may offer a promising new private-sector strategy for reducing the health harms of SSB intake. Trial Registration ClinicalTrials.gov identifier:NCT02585336
Integrated management model for clinical rescue of severe HFMD patients

The Hand, Foot, Mouth Disease (HFMD) is an infectious disease posing a severe threat to infant/children's health and even life in the worst case. Guangdong province takes a proactive stand in exploring the paths and measures to generally upgrade the clinical cure capabilities. In doing so,the province mobilizes resources of the entire province to normalize the rescue and treatment of severe HFMD cases, gradually lowering the fatality rate of the disease in the province. Key words: HFMD; Clinical cures Integrated management; Training
Blocking zero forcing processes in Cartesian products of graphs

Abstract In a zero forcing process, an initial vertex coloring of a graph is updated iteratively according to the following conversion rule: an uncolored vertex becomes colored if it is the only uncolored neighbor of some colored vertex. In this process, a zero forcing set is an initial set of colored vertices such that all the remaining vertices will ultimately change from uncolored to colored, and the zero forcing number is the minimum cardinality of a zero forcing set. We investigate two related concepts: a zero blocking set is the complement of a set which is not a zero forcing set, and the zero blocking number is the minimum cardinality of a zero blocking set. We provide a tight upper bound for the zero blocking number of Cartesian products of two arbitrary graphs. Exact values that are smaller than this general upper bound are also established when one of the graphs in the product is a cycle and the other is a path with at least as many vertices as the cycle.
The gridded retarding ion drift sensor for the petitSat cubeSat mission

The Gridded Retarding Ion Drift Sensor (GRIDS) is a small sensor that will fly on the 6 U petitSat CubeSat. It is designed to measure the three-dimensional plasma drift velocity vector in the Earth’s ionosphere. The GRIDS also supplies information about the ion temperature, ion density, and the ratio of light to heavy ions present in the ionospheric plasma. It utilizes well-proven techniques that have been successfully validated by similar instruments on larger satellite missions while meeting CubeSat-compatible requirements for low mass, size, and power consumption. GRIDS performs the functions of a Retarding Potential Analyzer (RPA) and an Ion Drift Meter (IDM) by combining the features of both types of instruments in a single package. The sensor alternates RPA and IDM measurements to produce the full set of measurement parameters listed above. On the petitSat mission, GRIDS will help identify and characterize a phenomenon known as plasma blobs (or enhancements).
Patient Misidentification Events in the Veterans Health Administration: A Comprehensive Review in the Context of High-Reliability Health Care

Objectives The Veterans Health Administration maintains national patient safety event reporting and root cause analysis (RCA) databases. These were reviewed to understand the prevalence of and provide insight into patient misidentification. The results were compared with a high-reliability health care framework. Methods We reviewed patient safety reports and RCA reports to identify and categorize patient identification-related events from October 1, 2016, to September 30, 2018. We analyzed 3232 patient safety reports and 67 RCAs, aggregated the findings, and compared them against The Joint Commission's High Reliability Health Care Maturity Model. Results Patient misidentification occurred in both inpatient and outpatient settings, for which the ratio of adverse events to close calls was similar. The ratio of adverse events to close calls varied for specific care areas. The most common RCA event characteristic was Two identifiers not used (39%). The most common failure mode was Procedure performed on wrong patient (31%). Issues related to policy and processes accounted for 42% of the root causes. Actions taken were primarily related to policy, process, and staff training/education (56%); these actions were rated as effective by the reporting facilities. Conclusions Patient misidentification is prevalent in both the inpatient and outpatient settings. However, specific care areas reported more close calls, an indicator of good safety culture. There were associations between policy and process issues, consistent use of 2 identifiers, and misidentification events. This review provides insight from the Veterans Health Administration national databases that health care institutions can use to improve their systems.
Existence and stability of some nonlinear ψ-Hilfer partial fractional differential equation

Abstract The main objective of this paper is to study properties of ψ -Hilfer partial fractional differential equations which are useful in modeling variety of phenomena in physical sciences. The existence, uniqueness, approximate solution and stability properties of solution are studied. The technique used for study is fixed point theorem and Gronwall inequality. Ulam–Hyers–Rassis stability of the solution is also investigated.
Childhood Material Hardship and Adolescent Mental Health

Adolescent mental health has implications for current and future wellbeing. While a link exists between poverty and mental health, little is known about how experiencing material hardship, such as ...
Preferential DNA-protein cross-linking by NiCl2 in magnesium-insoluble regions of fractionated Chinese hamster ovary cell chromatin.

Abstract Intracellular nickel ions (Ni 2+ ) have been shown to cause single-strand breaks in DNA, that were rapidly repaired, and DNA-protein cross-links, that persisted for at least 24 h following removal of extracellular ionic nickel. In this study, we have used the techniques of alkaline elution, chromatin fractionation, and sodium dodecyl sulfate:polyacrylamide gel electrophoresis to examine the DNA-protein cross-linking induced by NiCl 2 in Chinese hamster ovary cells. Continuous treatment of logarithmically growing Chinese hamster ovary cells with 2.5 mm NiCl 2 in complete medium resulted in DNA single-strand breaks within 1 h, followed by a time-dependent increase in the induction of DNA-protein cross-links at 2, 3, and 6 h. Since the entry of nickel into cells was maximal within 2 h of exposure, the time delay for the formation of DNA-protein cross-links was not limited by metal uptake. The nickel-induced DNA-protein cross-linking appeared to require active cell cycling, since single-strand breaks but no cross-linking could be detected in confluent cells treated with 1, 2.5, or 5 mm NiCl 2 for 3 h. DNA-protein cross-linking induced by nickel occurred in late S phase of the cell cycle. High-molecular-weight nonhistone chromatin proteins and possibly histone H1 migrating at the M r 30,000 range became cross-linked to DNA after treatment of cells with NiCl 2 . All nickel-cross-linked proteins were concentrated in the magnesium-insoluble regions of fractionated chromatin and were stable to urea, 2-mercaptoethanol, and Nonidet P-40. Some proteins ( M r 48,000, 52,000, 55,000, 70,000, and 95,000), the association of which with DNA was also stable to Sarkosyl, salt, and EDTA, were detectable in DNA rigorously fractionated from untreated cells. Nickel therefore appeared to cause the cross-linking of proteins that normally reside in close association with DNA. Alterations of the normal association of these proteins with DNA by nickel may be an early event in the nickel transformation process.
Application-Level Fault Tolerance as a Complement to System-Level Fault Tolerance

As multiprocessor systems become more complex, their reliability will need to increase as well. In this paper we propose a novel technique which is applicable to a wide variety of distributed real-time systems, especially those exhibiting data parallelism. System-level fault tolerance involves reliability techniques incorporated within the system hardware and software whereas application-level fault tolerance involves reliability techniques incorporated within the application software. We assert that, for high reliability, a combination of system-level fault tolerance and application-level fault tolerance works best. In many systems, application-level fault tolerance can be used to bridge the gap when system-level fault tolerance alone does not provide the required reliability. We exemplify this with the RTHT target tracking benchmark and the ABF beamforming benchmark.
Crystal structure of the Campylobacter jejuni CmeC outer membrane channel

As one of the world's most prevalent enteric pathogens, Campylobacter jejuni is a major causative agent of human enterocolitis and is responsible for more than 400 million cases of diarrhea each year. The impact of this pathogen on children is of particular significance. Campylobacter has developed resistance to many antimicrobial agents via multidrug efflux machinery. The CmeABC tripartite multidrug efflux pump, belonging to the resistance-nodulation-cell division (RND) superfamily, plays a major role in drug resistant phenotypes of C. jejuni. This efflux complex spans the entire cell envelop of C. jejuni and mediates resistance to various antibiotics and toxic compounds. We here report the crystal structure of C. jejuni CmeC, the outer membrane component of the CmeABC tripartite multidrug efflux system. The structure reveals a possible mechanism for substrate export.
Views of Graham Challenged

In Reply.— Dr Christoffel and her colleagues would have been correct if they had surmised that the author9s intent was to promote discussion of the way in which public policy has been and is made in such important matters as the nutritional status and health of our children, as well as the prevention of low birth weight and its associated morbidity and mortality. If they are regular readers of Pediatrics they know that the journal has long had a "Letters" section in which readers have the opportunity to comment on published material.
Gender, Race, and the Writing of Empire: The concentration camps controversy and the press

Still reeling from the series of setbacks in December 1899 that came to be known as Black Week, the British army by March 1900 had settled on a new strategy to try to finish the war in South Africa – the war that General Lord Roberts had said would be over by Christmas. Searching for a way to cut off Boer fighters in the field from food and supplies, the British, under the command of Lord Roberts, began to burn the homes and crops of the South African men who were away on commando duty. The farm-burning policy became systematic under Lord Kitchener, who succeeded Roberts as commander-in-chief of the British forces in South Africa in December 1900. Many African settlements and crops in the Orange Free State and the South African Republic (the Transvaal) were added to the list of what was to be “cleared,” and Kitchener was left with the problem of what to do with all the noncombatants thus displaced. In September of that year General John Maxwell had formed camps for surrendered burghers in Bloemfontein and Pretoria, and on 20 December 1900 Kitchener officially proclaimed a South Africa-wide policy whereby surrendered burghers and their families would be housed and fed in such camps, courtesy of the British military.
CD40 ligation triggers COX-2 expression in endothelial cells: evidence that CD40-mediated IL-6 synthesis is COX-2-dependent

Objective: To investigate whether CD40-CD154 interactions on HUVEC can trigger COX-2 synthesis as well as PGE2 and PGI2 secretion in vitro and explore whether the CD40-triggered prostanoids provide costimulatory signals for IL-6 secretion in this cell type.¶Materials and Methods: COX-2 protein expression was examined in HUVEC using Western blot analysis. ELISAs were employed to assess PGE2, PGI2 and IL-6 synthesis.¶Results: We found that COX-2 expression is upregulated when HUVEC are cultured with CD154+ D1.1 cells but not CD154– B2.7 cells. This effect was specifically inhibited by anti-CD154 mAb, and was amplified by the presence of IFNγ. Analysis of cell supernatants showed a concomitant rise in PGE2 and PGI2 secretion triggered by CD154+ D1.1 cells, or rsCD154. Use of selective (NS-398) and non-selective (ibuprofen) COX-2 inhibitors effectively inhibited prostanoid synthesis triggered by CD40 ligation. Reduction in prostanoid levels by NS-398 was accompanied by a reduction in IL-6 secretion levels triggered by CD40 ligation. Furthermore, exogenously added PGE2 triggered a dose-dependent IL-6 secretion, which was unaffected by NS-398.¶Conclusions: These studies demonstrate that CD40 ligation upregulates HUVEC COX-2 expression and function. Moreover, the data strongly suggest that CD154-induced IL-6 secretion in HUVEC is dependent on COX-2 activity.
Doxycycline pharmacokinetics in the absence of renal function.

Doxycycline pharmacokinetics in the absence of renal function. Doxycycline is a new tetracycline that is now in widespread clinical use. It differs from the other tetracycline drugs in many important respects including small daily dosage schedules, essentially complete upper gastrointestinal absorption and excretory characteristics that are independent of renal function. Our studies demonstrate that in anephric patients and patients with varying degrees of renal function the plasma t½ of biologically active doxycycline is not significantly extended and that in such a clinical situation the usual therapeutic regimen of the drug is necessary. Clearance rate of the compound from the systemic circulation by hemodialysis is only 10ml/min or less. In addition, our investigations identify the importance of the nonhepatic gastrointestinal pathway of elimination of doxycycline from the systemic circulation. Doxycycline therefore appears to be unique among the tetracyclines in that it may be utilized as a drug of choice for the therapy of systemic infections when a tetracycline compound is indicated in the clinical setting of impaired renal function. Pharmacocinetique de la doxycycline en l'absence de fonction renale. La doxycycline est une nouvelle tetracycline dont l'usage clinique est maintenant largement repandu. Elle differe des autres tetracyclines a plusieurs egards importants parmi lesquels la faible posologie quotidienne, l'absorption totale dans la partie haute du tractus digestif et des modalites d'excretion independantes de la fonction renale. Notre travail demontre que chez les sujets anephriques et les malades atteints d'insuffisance renale de severite variable la demie vie de la doxycycline biologiquement active n'est pas significativement allongee et que dans ces situations cliniques les modalites therapeutiques habituelles sont necessaires. La clearance du compose observee au cours de l'hemodialyse est egale ou inferieure a 10 ml/min. De surcroit nos travaux identifient l'importance de la voie d'elimination hepatique non intestinale de la doxycycline. La doxycycline apparait donc etre unique parmi les tetracyclines en ce sens qu'elle peut etre utilisee comme une drogue de choix pour le traitment des infections systemiques quand une tetracycline est indiquee et qu'il existe une alteration de la fonction renale.
Primary and secondary structure of black beetle virus RNA2, the genomic messenger for BBV coat protein precursor

Abstract The nucleotide sequence of black beetle virion (BBV) RNA2 has been determined. RNA2 is 1399 b long. Its 5' terminus is capped. Its 3' terminus has an unidentified moiety that renders the RNA resistent to polyadenylation and ligation. The first AUG codon at base 23 is followed by an open reading frame for a protein 407 amino acids long, the predicted size of coat protein precursor. A second open reading frame for a putative protein 72 amino acid residues long begins at base 1110. No other large open reading frames exist. The 5' half of the RNA can be folded into a long, imperfect hairpin of high predicted stability. The 3' half of the RNA can fold into a complex set of multiply bifurcated stem and loop regions.
Selective cleavage of kinetoplast DNA minicircles promoted by antitrypanosomal drugs.

Abstract Pentamidine, diminazene aceturate (Berenil), isometamidium chloride (Samorin), and ethidium bromide, which are important antitrypanosomal drugs, promote linearization of Trypanosoma equiperdum minicircle DNA (the principal component of kinetoplast DNA, the mitochondrial DNA in these parasites). This effect occurs at therapeutically relevant concentrations. The linearized minicircles are protease sensitive and are not digested by lambda exonuclease (a 5' to 3' exonuclease), indicating that the break is double stranded and that protein is bound to both 5' ends of the molecule. The cleavage sites map to discrete positions in the minicircle sequence, and the cleavage pattern varies with different drugs. These findings are characteristic for type II topoisomerase inhibitors, and they mimic the effects of the antitumor drug etoposide (VP16-213, a semisynthetic podophyllotoxin analog) on T. equiperdum minicircles. However, the antitrypanosomal drugs differ dramatically from etoposide in that they do not promote detectable formation of nuclear DNA-protein complexes or of strand breaks in nuclear DNA. Selective inhibition of a mitochondrial type II topoisomerase may explain why these antitrypanosomal drugs preferentially disrupt mitochondrial DNA structure and generate dyskinetoplastic trypanosomes (which lack mitochondrial DNA).
Digital Volume Correlation for Study of the Mechanics of Whole Bones

Full-field measurement of deformation in biological structures such as bones is a promising experimental approach for study of the spatial heterogeneity in mechanical behavior. With the advent of high-resolution, 3-D imaging, digital volume correlation (DVC) allows for the measurement of spatially heterogeneous, 3-D deformation fields throughout entire volumes. For bones such as the vertebra, use of DVC to detect the onset and progression of failure is of direct relevance to the study of osteoporotic fractures. Application of DVC to whole bones, as opposed to machined specimens of bone tissue, involves additional challenges such as the irregular geometry, large data sets, and decreased signal-to-noise ratio. These challenges are addressed in this paper, and the DVC method that results is used to examine yield and post-yield deformations in vertebral compression experiments.
Brass Balls: Masculine Communication and the Discourse of Capitalism in David Mamet's Glengarry Glen Ross:

David Mamet has referred to his Pulitzer Prize-winning play, Glengarry Glen Ross, as a “gang comedy about men, work, and unbridled competition.” This essay explores this imbrication of masculinity ...
Development and In Vitro - In Vivo Evaluation of Fenretinide-Loaded Oral Mucoadhesive Patches for Site-Specific Chemoprevention of Oral Cancer

Purpose To develop fenretinide oral mucoadhesive patch formulations and evaluate their in vitro and in vivo release performance for future site-specific chemoprevention of oral cancer.
Individual differences in anger and sad expressions during extinction: Antecedents and consequences.

This experiment examined individual differences in 2-to 8-month-olds' emotional expression during a contingency learning task consisting of three phases: learning, extinction, and relearning. Infants who had learned to pull to activate an audiovisual display showed anger and/or sadness during extinction. This differential negative reaction had different consequences for infants' subsequent emotional expression during relearning. Anger during extinction led to maintained or renewed interest, whereas sadness led to decreased enjoyment. These different patterns suggest individual differences in affective processing which may be precursors to later dimensions of personality.
Nanoscale 3D Dynamics of Optically Trapped Spheres Interacting with Adherent Cell Lamellae

We demonstrate an optical trap instrument and experimental methodology for reporting the nanoscale dynamics of binding individual cell-surface receptors and the cyto-mechanical responses initiated by bi-directional outside-in and inside-out signals. The probe, a 1-μm diameter chemically labeled glass sphere held in the trap, is positioned above the lamella of an adherent motile cell (cf. figs. A-B), and tracked in 3D at a framing rate of ∼100/s. In addition to a lateral precision of 2nm in 2D tracking, we have developed a practical approach to incorporate a comparable 4-6 nm precision in vertical tracking of the trapped sphere. We apply a novel Brownian analysis of vertical probe fluctuations in soft contact with the cell lamella to determine the apparent rigid boundary of the cell surface and elastic compliance of the glycocalyx. The adherent motile leukocytic (Jurkat) cells were spread on coverglass coated with the α4β1-integrin ligand VCAM-1 in isotonic Ca2+ and/or Mg2+ buffers. Spheres were conjugated with fibronectin fragments to demonstrate the nanoscale dynamics of integrin ligation and release (cf. figs. C-D), the measurement of bond-surface separation and extensional compliance, plus intriguing transient subsurface movements triggered by bond formation.View Large Image | View Hi-Res Image | Download PowerPoint Slide
A physical representation for scattering matrices employing complex normalization

Scattering matrix problems requiring complex normalization can be converted to real normalization problems. This letter shows how this may be accomplished by defining a new port voltage applicable to a simple modification of the original network being considered.
A Simple Modification to Add Strength to the Roeder Knot

The Roeder knot is commonly used during laparoscopic suturing because it may be tied extracorporeally and slid down to the target tissue with a single pass of a knot pusher. However, it is significantly weaker than extracorporeally tied knots with several throws. We compared the usual Roeder knot to one that was modified by adding a fourth loop around the standing end of the suture and a second half-hitch to the completed knot. The modified knot (26.6 newtons +/- 15.3) was significantly stronger (p <0.05) than the standard Roeder knot (18.0 newtons +/- 12.1). If a single-pass extracorporeal knot is to be used, we recommend a modified Roeder knot when ligating pedicles at laparoscopy.
Necessary, But Not Sufficient: The Importance of Family and School for Youth at Risk of Heavy Episodic Drinking

Adolescent heavy episodic drinking is of significant concern to social workers. This secondary analysis uses the 2007 National Survey on Drug Use and Health to explore the relationship of family and school factors to adolescent heavy episodic drinking. The sample included 17,727 adolescents between the ages of 12 and 17. The findings indicate that family and school factors are protective on the bivariate level. Yet, the hypotheses were only partially supported on the multivariate level, demonstrating that risk is cumulative. The data suggest that social work interventions must be sustained, implemented within multiple environments, and begun prior to adolescence.
THE DESIGN OF BUNCHING MAGNETS

Abstract The design of a bunching magnet of the type suggested by Mobley and Van de Graaff has been investigated. A relationship between the magnetic flux and the difference in length of the extreme paths is presented. The properties of a uniform-field sector magnet with fringing-field focusing were investigated in detail. It was found that the divergence of the initial beam from an electrostatic accelerator could be expected to limit the maximum attainable bunching ratio (ratio of input acceptance time to output pulse width) when sinusoidal deflection is used. A slightly more complex deflection system increased the maximum attainable bunching ratio.
Limitations of the Chemical Potential

tion of transport by diffusion. A typical example of this concept is illustrated by a quote from Salisbury and Ross
Hybrid Ventricular Decompression in Pulmonary Atresia With Intact Septum

Initial palliation for pulmonary atresia with intact ventricular septum continues to evolve in the face of significant early and late morbidity. In patients with suitable anatomy, decompression of the right ventricle may be the first step in treatment. A hybrid approach to right ventricular decompression, combining surgery and interventional catheterization techniques is described. Direct access to the right ventricle through a subxiphoid incision with transventricular sheath placement is used to provide optimum catheter position for radiofrequency perforation of membranous pulmonary atresia followed by balloon dilation. The technique may address key limitations of the traditional surgical and interventional approaches.
Editorial on “Simultaneous resections of colorectal cancer and synchronous liver metastases: a multi-institutional analysis”

Liver resection has become the standard treatment for metastatic colorectal cancer.1 Such procedures are now justified by the increasing safety of hepatic resections and by documentation of long-term disease-free survival.1,2 Metastatic disease confined to the liver is now routinely resected as part of a potentially curative strategy. When patients present with liver metastases synchronous with a colorectal primary, however, the timing of surgical treatment remains controversial. In studies published as late as the 1990s, prohibitive perioperative mortality was reported when combining major liver resections with resection of the colorectal primary. An operative mortality as high as 17% was reported for such simultaneous resections.3 Because of this and other reports, many centers have been reluctant to perform simultaneous resections, but rather have favored resecting the primary and liver metastases at two separate operations. The report in the current issue by Reddy and his colleagues presents the experience of simultaneous resections from three centers over a 20-year period4; these results add to an emerging literature suggesting simultaneous resections to a safe surgical strategy.
The principle of indirect means in language use and language structure

Abstract The study proposes that in some languages, there exists a principle according to which indirect rather than direct means of expression are used whenever the goals of speech involve certain functional domains. We call this the Principle of Indirect Means. Direct means are those that grammatically or lexically encode a given function without dependence on contextual knowledge. Indirect means are those that although they code function A within the grammatical system of the language, are deployed for the coding of function B. The principle allows us to provide a unified explanation for certain phenomena in language use and language structure that in the past received unrelated explanations. The Principle of Indirect Means, a principle of language use, exerts a powerful force on language change. It creates a major motivation for grammaticalization and results in a richness of means of expression in the domains to which it applies. The Principle of Indirect Means is also a major motivation for the creation of metaphors. The present study defines the principle, provides the evidence for its existence, and describes the implication of the principle for language use, language structure, and language change. The study also posits several typological questions. The argumentation in this study is based on cross-linguistic data.
The (n, n)-disconjugacy of a 2nth order linear difference equation

Abstract We give a formulation of generalized zeros and (n, n) disconjugacy for even order formally self-adjoint scalar difference equations. Positive definiteness of an associated quadratic functional is shown to imply (n, n) disconjugacy. This study is motivated by the open question of existence of a Reid roundabout theorem for singular discrete linear Hamiltonian systems.
Subcompact free-electron laser

The far-infrared portion of the electromagnetic spectrum has remained largely unexplored, partially as a consequence of a lack of suitable sources. The Stanford Far-Infrared Free- Electron Laser has recently demonstrated lasing at 86 micrometers . With component costs, space, shielding requirements, and complexity reduced by up to an order of magnitude from conventional designs, this places the far-infrared free-electron laser within the reach of an individual researcher or a research department. Results from the most recent experimental run are presented. The accelerator section is currently undergoing redesign to make it more suitable for free-electron laser use.
Activation Parameters for the Carbon−Cobalt Bond Homolysis of Coenzyme B12 Induced by the B12-Dependent Ribonucleotide Reductase from Lactobacillus leichmannii

The temperature dependence of the kinetics of the rapid, reversible cleavage of the carbon−cobalt bond of 5‘-deoxyadenosylcobalamin (AdoCbl, coenzyme B12) catalyzed by the ribonucleotide triphosphate reductase (RTPR) of Lactobacillus leichmannii has been studied by stopped-flow spectrophotometry. At a given temperature and constant concentration of AdoCbl, the observed rate constants, kobs, are essentially independent of the initial concentration of RTPR, but the spectral change, and hence the amount of cob(II)alamin formed at equilibrium, shows a hyperbolic dependence on [RTPR]0. This is interpreted as being a consequence of the known relatively weak binding of AdoCbl to the enzyme so that increasing enzyme concentration drives the binding equilibrium toward enzyme−coenzyme complex. Fitting the absorbance change data to a binding isotherm gives values of the binding equilibrium constant, Kb, and the maximal absorbance change obtainable when the coenzyme is “saturated” with enzyme. From the latter value a...
Evaluation of similarity models for expected utility violations

A body of work proposes a decision cost argument to explain expected utility (EU) violations based on pair similarity. These similarity models suggest various measures over the risky pairs that define decision costs and benefits. This paper assesses the empirical modeling success of these similarity measures in explaining risky choice patterns showing EU independence violations. We also compare model fit for these similarity models relative to EU and to a selected generalized EU model. Although the candidate models exhibit some degree of substitutability, our results indicate support for models that use relatively simple measures as instruments for similarity.
Validation of domain-referenced test items.

Studies of validation of domain-referenced tests (DRT) focus almost exclusively on content validation, while eminent researchers caution against neglecting construct validity. This paper discusses issues re lated to construct validation and reports the validation results for a DRT. Specifically, this study evaluates the substantive construct validity of DRT items. Items for objectives in clinical dietetics were administered to a national sample of students. An index of item response homogeneity was used as an indicator of substantive construct validity. Results suggest evidence for that type of validity.
Single-crystal elasticity of pyrope and MgO to 20 GPa by Brillouin scattering in the diamond cell

The single-crystal elastic properties of synthetic pyrope (Mg3Al2Si3O12) and periclase (MgO) have been measured by Brillouin scattering in a diamond anvil cell (DAC) up to 20 GPa. A 16:3:1 mixture of methanol–ethanol–water was used as a pressure-transmitting medium. Above the freezing pressure of this medium (∼14 GPa), heat treatment and accompanying stress relaxation produces quasi-hydrostatic conditions. An analysis of geometric errors associated with the DAC indicates that the DAC introduces an additional uncertainty in velocity of ≤0.5% (as compared to measurements in air), if there is no vignetting of the incident and scattered beams. The nonhydrostaticity caused by freezing of the pressure-transmitting medium results in lower velocities and elastic moduli than are obtained under hydrostatic conditions, and this leads to an overestimation of the second pressure derivatives of the elastic moduli. Fitting our hydrostatic data to finite-strain equations of state yields the following adiabatic bulk (KS) and shear (μ) moduli and their pressure derivatives: KS=163.2(10), K′=3.96(10), Kʺ=−0.044(20), μ=130.2(10), μ′=2.35(10), μʺ=−0.040(20) for MgO and KS=171.2(20), K′=4.1(3), μ=93.7 (20), μ′=1.3(2) for pyrope, where primes indicate pressure derivatives of moduli. Our results for MgO are in excellent agreement with previous ultrasonic measurements performed at lower pressures, and in particular the values of K′ agree to within a few percent. Our data are in good agreement with recent compression measurements on pyrope to pressures exceeding 20 GPa, suggesting that Brillouin scattering is an accurate method for high-pressure density and elastic moduli measurements. Pyrope is nearly elastically isotropic at ambient conditions and remains isotropic over the pressure range studied here. In contrast, the elastic anisotropy of MgO is observed to decrease dramatically with increasing pressure, becoming elastically isotropic at ∼21.5 GPa.
The performance of push and pull systems: a simulation and comparative study

Ideally the just-in-time (pull system) production system holds no buffer inventory so that the production is ‘just in time’. This is achieved only when the stage's operation times are constant and equal; but realistically the variability of operator performance and/or the unequal distribution of task times precludes such an ideal situation. As a result, the production line experiences problems. In this paper we investigate the effects of these variabilities on the performance of push and pull systems and how the manager can decide which production technique to adopt. The implication of the simulation results are reported and openings for future research are identified.
Comparison Of Four Methods Of Interferogram Reduction And Interpretation

This paper will address the problem of accurate reduction and interpretation of interferograms. Peak-to-valley wavefront deformation will be the main criterion of evaluation. Interferograms containing power, spherical aberration, coma, and astigmatism will be evaluated using four different methods. These methods will be (1) visual interpretation using a ''harp,'' (2) manual interpretation, (3) automatic digitization (Zygo Zapp), and (4) computer interpretation (fringe). The strengths and weaknesses of these methods, including cost, time, accuracy, and repeatability, will be discussed. Reference will be made to ''Optical Interferograms-Reduction and Interpretation'' an ASTM publication. 2 refs., 5 figs.
Bidirectional reflectance factors of agricultural targets: A comparison of ground-, aircraft-, and satellite-based observations

Abstract The bidirectional reflectance factor (BRF) of most natural surfaces exhibits substantial departure from lambertian behavior, yet the magnitude of its effect in off-nadir imagery from the SPOT satellite remains mostly undocumented. Field investigations were conducted at the Maricopa Agricultural Center in Arizona to explore this phenomenon using three wavelength intervals (green, 0.50-0.59 μm; red, 0.61-0.68 μm; and NIR, 0.79-0.89 μm). During 1988 and 1989 observations spanned two consecutive days during which the SPOT radiometer viewing angles differed by 34°. Ground-based BRFs were obtained for nadir and off-nadir viewing angles over replicated transects in cultivated soil, cotton, and wheat fields using radiometers mounted on a backpack. Aircraft data were measured from flight lines about 150 m above ground level with a nadir-oriented radiometer. SPOT digital imagery was converted to ground equivalent BRFs using specific calibration factors for the sensor, estimates of exoterrestrial radiation, solar zenith angles, and measurements of atmospheric optical depths. Reflectance factors varied with sensor, target, wavelength interval, and viewing and illumination geometry. Ground data were a strong function of solar zenith angle, revealing systematic differences in BRF behavior of each cover type. Good agreement was found between ground- and aircraft-based observations collected with nadir-pointed radiometers. For each wavelength interval, linear regression yielded R 2 > 0.99 and regression slopes averaging 0.96. Ground and aircraft data also revealed negligible changes in day-to-day reflectance from cultivated soil, cotton, and wheat targets. However, large differences were observed in SPOT imagery acquired on consecutive days. As expected, correlations between nadir aircraft observations and off-nadir satellite data were relatively poor ( 0.66 2 ) partially due to differences in sensor viewing angles. Off-nadir satellite and off-nadir ground data were better correlated ( 0.91 2 ). However, satellite-based BRFs were nearly double the ground-based values at low levels of reflectance (visible bands over dense vegetation). Possible reasons for discrepancies between satellite and ground off-nadir measurements include systematic bias in surface reflectance measurements, inadequate atmospheric correction of satellite data, adjacency effect from nearby surfaces, and inaccurate satellite sensor calibration.
High-resolution dating of granite petrogenesis and deformation in a lower crustal shear zone: Athabasca granulite terrane, Western Canadian Shield

Abstract The Athabasca granulite terrane represents > 20,000 km 2 of continental lower crust exposed in the hanging wall of the ca. 1.85 Ga thrust–sense Legs Lake shear zone in the western Canadian Shield. The terrane and the thrust zone are cut by the Grease River shear zone. The structure hosts a syn-tectonic granite dike with a high-precision ID-TIMS zircon 207 Pb/ 206 Pb crystallization age of 1922.6 ± 0.4 Ma (MSWD = 3.1, 2 σ ). Detailed textural analysis and in situ electron probe microanalysis (EPMA) of monazite in the dike indicate three discrete episodes of strain accumulation, each corresponding to syn-kinematic growth of monazite. The results provide evidence for a previously unrecognized > 100 m.y. episodic record of sub-horizontal NW–SE shortening and dextral shear strain along the Grease River shear zone. High-Ca domains in ca. 1.92–1.90 Ga monazite are linked to protracted high- T strain (ca. 650–700 °C) at lower crustal depths (ca. 1.0 GPa) and correlated with indentation of the Slave craton along the Great Slave Lake shear zone. Syn-kinematic overgrowths of low-Ca monazite + apatite are interpreted as products of deformation-enhanced dissolution and re-precipitation of monazite at 1846 ± 9 Ma (MSWD = 1.1, 2 σ ). The third generation of syn-kinematic monazite yield ca. 1.8 Ga ages. The dataset constrains, for the first time, coeval movement along the strike–slip Grease River shear zone and the thrust–sense Legs Lake shear zone during ca. 1.85 Ga dextral transpression and uplift of continental lower crust to middle crustal levels (ca. 0.5 GPa). Circa 1.8 Ga syn-kinematic monazite domains in dynamically recrystallized feldspars support brittle–ductile reactivation along the Grease River shear zone at shallower crustal levels, coincident with intra-continental strike–slip strain during culmination of the Trans-Hudson orogeny.
Alternative representations of time, number, and rate.

Abstract Three facts of time perception are described based upon a temporal generalization task for rats (the peak procedure) in which food reinforcement is derivered on half the trials following the first lever-press response after some fixed interval after signal onset. (1) The mean response rate as a function of time is a smooth, slightly asymmetric, function with a maximum near the time of reinforcement; (2) the response rate on individual trials is characterized by an abrupt change from a state of low responding to a state of high responding and finally another state of low responding (break-run-break pattern); and (3) the mean response rate in 12-s and 20-s peak procedures is similar when plotted against time relative to the time of reinforcement (superposition). An information-processing version of scalar timing theory is described and compared to an alternative connectionist version of scalar timing theory that involves multiple oscillators and an autoassociation network. Psychological, mathematical and biological descriptions of the two versions are described and some possible extensions of the connectionist version are proposed to deal with perception of number, rate, and spatial orientation.
A Numerical Study of Strong Katabatic Winds over Antarctica

Abstract Certain coastal sections of Antarctica, most notably Adelie Land and Terra Nova Bay, experience anomalously intense, persistent katabatic winds. The forcing of such katabatic outflow is believed to originate several hundred kilometers upslope in the interior of the continent where cold air drainage currents from a large area converge into a relatively narrow zone focused on the steeply-sloping ice terrain near the coastline. Numerical simulations with a three-dimensional hydrostatic model incorporating terrain features representative of Adelie Land reveal a significant topographical channeling of the surface airflow. Katabatic wind speeds as depicted by the model are greatly enhanced downslope of the convergence channel. These results emphasize the importance of topography in the continental interior in shaping the character of coastal katabatic flow.
Toward consistent snapshot of the digitized battlefield

A battlefield can be viewed as a collection of entities, enemy and friendly, during combat, each entity scans its surrounding with local sensors to be aware of the current situation. Through digitation of the battlefield, it is possible to share this locally sensed information among all the friendly entities. Significant war-fighting advantages can be realized, if this shared information is consistent. During one of the soldier-in-the-loop simulation exercises invovling ground-based enemy and friendly entities, it was found that achieving consistent snapshot at each friendly node is not a trivial problem. A few contributing factors are: suitable method for combining individual perspective to a global one, mode of communication, movement of all entities, different local perspective of each entity, sensor calibration, fault, and clock synchronization. At the US Army VETRONICS Technology Center, we are in the process of developing a family of algorithms capable of obtaining a consistent global picture invovling one of the critical properties, ground position of entities. In the first stage we have established that for point to point communicating entities, a vector clock based scheme uses fewer number of messages and arrives at the global picture earlier. However, this result does not scale to broadcast situations.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Toward a Platinum Standard for Evidence-Based Assessment by 2020

The authors argue for a scientifically rigorous, contextually valid, practically relevant, and stakeholder-inclusive Platinum Standard for evidence-based assessment to improve public administration and third-party governance in the twenty-first century. The Platinum Standard would encompass two contending gold standards. The first gold standard, based on experimental methods, counterfactuals, and average causal effects, is better known and more institutionalized in practice. The second gold standard, based on case studies, comparative methods, triangulation, and causal mechanisms, is less known. The Platinum Standard incorporates both sets of standards and provides a framework for integrating them in practice. It recognizes the wide array of goals and methodologies that are appropriate for assessing the performance of public administration and third-party governance initiatives in a dynamic and globalizing world. The two gold standards currently compete for prominence in the field of evidence-based assessment. By 2020, these gold standards should be part of a more inclusive Platinum Standard.
Retrospective utility of bronchoscopy after hematopoietic stem cell transplant

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is thought to be the procedure of choice to evaluate pulmonary infiltrates in hematopoietic stem cell transplant (HSCT) recipients. We retrospectively reviewed 91 bronchoscopies performed on 190 in-patient HSCT recipients admitted or treated for pneumonia from January 1994 to December 2004. These yielded a diagnosis 49% of the time with an overall survival of 35 days post-bronchoscopy. We were unable to detect any survival benefit from an addition to the treatment regimen after a positive result from analysis of the BAL fluid or transbronchial biopsy. The most common bacteria isolated was Pseudomonas that was often resistant to the patient's current antibiotics, suggesting that in lieu of this diagnostic procedure, changes to better cover resistant Gram-negative bacteria are reasonable. Although transbronchial biopsies provided an additional diagnosis in one out of 21 biopsies performed, six of the seven complications in our series were directly related to the transbronchial biopsy. With approximately a 50% yield from a bronchoscopy, additional treatment given after only 20% of all bronchoscopies, and no detectable survival benefit with a bronchoscopy that yielded a diagnosis, the utility of a bronchoscopy in this patient population is questioned by these data.