cssi/SciSciGPT-SciSciNet huggingface dataset:
Does vancomycin prescribing intervention affect vancomycin-resistant enterococcus infection and colonization in hospitals? A systematic review

Vancomycin resistant enterococcus (VRE) is a major cause of nosocomial infections in the United States and may be associated with greater morbidity, mortality, and healthcare costs than vancomycin-susceptible enterococcus. Current guidelines for the control of VRE include prudent use of vancomycin. While vancomycin exposure appears to be a risk factor for VRE acquisition in individual patients, the effect of vancomycin usage at the population level is not known. We conducted a systematic review to determine the impact of reducing vancomycin use through prescribing interventions on the prevalence and incidence of VRE colonization and infection in hospitals within the United States. To identify relevant studies, we searched three electronic databases, and hand searched selected journals. Thirteen studies from 12 articles met our inclusion criteria. Data were extracted and summarized for study setting, design, patient characteristics, types of intervention(s), and outcome measures. The relative risk, 95% confidence interval, and p-value associated with change in VRE acquisition pre- and post-vancomycin prescription interventions were calculated and compared. Heterogeneity in study results was formally explored by stratified analysis. No randomized clinical trials on this topic were found. Each of the 13 included studies used a quasi-experimental design of low hierarchy. Seven of the 13 studies reported statistically significant reductions in VRE acquisition following interventions, three studies reported no significant change, and three studies reported increases in VRE acquisition, one of which reported statistical significance. Results ranged from a reduction of 82.5% to an increase of 475%. Studies of specific wards, which included sicker patients, were more likely to report positive results than studies of an entire hospital including general inpatients (Fisher's exact test 0.029). The type of intervention, endemicity status, type of study design, and the duration of intervention were not found to significantly modify the results. Among the six studies that implemented vancomycin reduction strategies as the sole intervention, two of six (33%) found a significant reduction in VRE colonization and/or infection. In contrast, among studies implementing additional VRE control measures, five of seven (71%) reported a significant reduction. It was not possible to conclusively determine a potential role for vancomycin usage reductions in controlling VRE colonization and infection in hospitals in the United States. The effectiveness of such interventions and their sustainability remains poorly defined because of the heterogeneity and quality of studies. Future research using high-quality study designs and implementing vancomycin as the sole intervention are needed to answer this question.
Learning, multiple equilibria, and the state: Agriculture’s role

This article will argue that the state must learn to pursue productivity enhancing rather than predatory policies if rapid long-run development is to occur in poor countries. These productivity enhancing strategies will most likely involve investment coordination. However, such coordination of investment in manufacturing is likely to fail in less developed countries as a result of low productivity in the traditional, agricultural sector. More importantly, investment coordination in agriculture is more likely to be successful especially if this is a broad based investment strategy involving the bulk of the population. In this context, the state will learn effective policies for coordinating development. Alternatively, if the agricultural sector is ignored and productivity here remains low, investment coordination in manufacturing will likely fail, and the state will learn to become a predator.
IMPROVED PROBE‐BASED ASSAY FOR THE QUANTIFICATION OF STAPHYLOCOCCUS AUREUS VIRULENCE REGULATOR, RNAIII, BOTH IN VITRO AND IN VIVO

Accessory gene regulator, a quorum-sensing operon, plays a key role in the Staphylococcus aureus pathogenesis by altering the expression of virulence determinants through its effector molecule, RNAIII. Several methods for RNAIII quantification have been described. However, methods that involve a signal amplification process are necessary to evaluate the contribution of RNAIII to the coordinate regulation of these virulence factors in specific niches, in vivo. Here, we described the development and validation of a specific probe-based reverse transcription quantitative PCR for the quantification of RNAIII that improves upon previously published methods. Using the 2−ΔΔCt algorithm, we demonstrated the necessity for matching the efficiencies of the primer/probe sets used, as lack of this prerequisite could lead to inaccuracy in quantification with subsequent misjudging of the role of different virulence determinants in disease pathogenesis. The RNAIII expression was evaluated in both laboratory strain and clinical isolate under in vitro/in vivo conditions to verify the robustness of the technique. PRACTICAL APPLICATIONS RNAIII is a global regulator that is involved and plays a key role in Staphylococcus aureus virulence. Quantifying RNAIII should be useful to understand the disease mechanisms of S. aureus in different animal models. Also, it would be useful for the screening of potential antivirulence drugs that can inhibit RNAIII-dependent virulence determinants. Together with reverse transcription quantitative PCR assays developed for other determinants, based on the strategy adopted here, this could provide a more detailed view of the signaling pathways that control S. aureus virulence.
Humane Intelligence: A Human Factors Perspective for Developing Intelligent Cockpits

A human factors perspective for creating intelligent cockpits is described and explained. A conceptualized interface among the pilots, mental models, and human information technologies is proposed wherein knowledge concerning human cognition is meshed with the capabilities and limitations of artificial intelligence (AI). Necessarily, a different way of looking at the pilot's role in the intelligent cockpit is developed.
Characterizing the Phenotypic Response of Endothelial Cells Cultured on Pro-Angiogenic In Vitro Tumor Mimics

Despite the 200 billion dollars invested in cancer therapy research and development since 1971, only 5% of new drugs entering clinical trials successfully obtain FDA approval [1, 2]. There is a growing concern in the cancer research community that this slow movement in progress stems from the need for improved preclinical models for testing new therapeutic agents [1]. A burgeoning interface between cancer research and tissue engineering is transforming how tumor development is being studied in vitro. As a result, complex 3D cancer cell culture models are beginning to be developed with phenotypes representative of in vivo cancer progression [3].Copyright © 2012 by ASME
An examination of the differential sensitivity to ketolide antibiotics in ermB strains of Streptococcus pyogenes and Streptococcus pneumoniae.

Several reports in the literature have described a differential sensitivity to ketolide antibiotics in ermB strains of Streptococcus pyogenes and Streptococcus pneumoniae resistant to erythromycin. Strains of S. pyogenes and S. pneumoniae carrying different erm gene alleles were examined for their susceptibility to the ketolide antibiotics cethromycin (ABT-773) and telithromycin. The effect of the antibiotics on cell growth and viability was assessed as were effects on protein synthesis and 50S ribosomal subunit formation. The susceptibility of wild-type strains of both organisms was compared with effects in strains containing the ermA and ermB methyltransferase genes. A wild-type antibiotic-susceptible strain of S. pyogenes was comparable to an ermA strain of the organism in its ketolide sensitivity, with IC50 values for 50% inhibition of protein synthesis and 50S ribosomal subunit formation of 10 ng/mL for cethromycin and 16 ng/mL for telithromycin. An S. pneumoniae strain with the ermB gene and an S. pyogenes strain with the ermA gene were also similar in their sensitivity to ketolide inhibition. IC50 values for inhibition of translation and subunit formation in S. pneumoniae (ermB) were 30 ng/mL and 55 ng/mL and for the ermA strain of S. pyogenes they were 15 ng/mL and 35 ng/mL respectively. By contrast, an S. pyogenes ermB strain was significantly more resistant to both ketolides, with IC50 values for inhibition of 50S synthesis of 215 and 380 ng/mL for the two ketolides. Experiments were conducted to examine ribosome synthesis and translational activity in the two ermB strains at intervals during growth in the presence of each antibiotic. Cell viability and 50S subunit formation were dramatically reduced in the S. pneumoniae strain during continued growth with either drug. By contrast, the ketolides had little effect on the S. pyogenes strain growing with the antibiotics. The results indicate that ketolides have a reduced inhibitory effect on translation and 50S subunit synthesis in S. pyogenes with the ermB gene compared with the other strains examined.
Atomic scale study of polar Lomer–Cottrell and Hirth lock dislocation cores in CdTe

Dislocation cores have long dominated the electronic and optical behaviors of semiconductor devices and detailed atomic characterization is required to further explore their effects. Miniaturization of semiconductor devices to nanometre scale also puts emphasis on a material's mechanical properties to withstand failure due to processing or operational stresses. Sessile junctions of dislocations provide barriers to propagation of mobile dislocations and may lead to work-hardening. The sessile Lomer-Cottrell and Hirth lock dislocations, two stable lowest elastic energy stair-rods, are studied in this paper. More specifically, using atomic resolution high-angle annular dark-field imaging and atomic-column-resolved X-ray spectrum imaging in an aberration-corrected scanning transmission electron microscope, dislocation core structures are examined in zinc-blende CdTe. A procedure is outlined for atomic scale analysis of dislocation junctions which allows determination of their identity with specially tailored Burgers circuits and also formation mechanisms of the polar core structures based on Thompson's tetrahedron adapted to reactions of polar dislocations as they appear in CdTe and other zinc-blende solids. Strain fields associated with the dislocations calculated via geometric phase analysis are found to be diffuse and free of `hot spots' that reflect compact structures and low elastic energy of the pure-edge stair-rods.
Study of Unrecovered Strain and Critical Stresses in One-Way Shape Memory Nitinol

Unique thermomechanical properties of Nitinol known as shape memory and superelasticity make it applicable for different fields such as biomedical, structural, and aerospace engineering. These unique properties are due to the comparatively large recoverable strain, which is being produced in a martensitic phase transformation. However, under certain ranges of stresses and temperatures, Nitinol wires exhibit unrecovered strain. For cyclic applications, it is important to understand the strain behavior of Nitinol wires. In this study, the unrecovered strain of different Nitinol wire diameters was investigated using constant stress experiment. Uniaxial tensile test has been also performed to find the range of critical stresses. It was observed that the unrecovered strain produced in the first loading-unloading cycle affects the total strain in the subsequent cycles. Moreover, a critical range of stress was found beyond which the unrecovered strain was negligible while the wires heated up to the range of 70-80°C, depending on the wire diameters. The unrecovered strain of wire diameters of 0.19 mm and less was found to be sensitive to the critical stress. On the other hand, for wire diameters bigger than 0.19 mm this connection between the unrecovered strain and the critical stress was not observed for the same range of heating temperature.
Quantifying myosin light chain phosphorylation in single adherent cells with automated fluorescence microscopy

In anchorage dependent cells, myosin generated contractile forces affect events closely associated with adhesion such as the formation of stress fibers and focal adhesions, and temporally distal events such as entry of the cell into S-phase. As occurs in many signaling pathways, a phosphorylation reaction (in this case, phosphorylation of myosin light chain) is directly responsible for cell response. Western blotting has been useful in measuring intracellular phosphorylation events, but cells are lysed in the process of sample preparation for western blotting, and spatial information such as morphology, localization of the phosphorylated species, and the distribution of individual cell responses across the population is lost. We report here a reliable automated microscopy method for quantitative measurement of myosin light chain phosphorylation in adherent cells. This method allows us to concurrently examine cell morphology, cell-cell contact, and myosin light chain diphosphorylation in vascular smooth muscle cells. Paraformaldehyde fixation and Triton X-100 permeabilization preserved cell morphology and myosin light chain phosphorylation better than the alternative fixation/permeabilization methods tested. We utilized automated microscopy methods to acquire three color images, determine cell spread area, and quantify the intensity of staining within each cell with anti-phospho-MLC antibody. Our results indicate that A10 rat aortic smooth muscle cells exhibit a re producible non-Gaussian distribution of MLC phosphorylation across a population of unsynchronized genetically identical cells. Adding an inhibitor of Rho kinase, Y27632, or plating cells on a low density of fibronectin, reduced phospho-myosin light chain signal as expected. On the other hand, adding calyculin A, an activator of contractility, increased myosin light chain phosphorylation. The IC50 for myosin light chain phosphorylation using Y27632 was determined to be 2.1 ± 0.6 micrometers. We observed a positive linear relationship between cell area and myosin light chain diphosphorylation, which is consistent with what has been reported in the literature using other methods. Our results show that using proper specimen fixation techniques and background subtraction methods, imaging cytometry can be used to reliably measure relative myosin light chain phosphorylation in individual adherent cells. Importantly, the ability to make this measurement in adherent cells allows for simultaneous measurement of and correlation with other parameters of cellular topography such as morphology and cell-cell proximity. This assay has potential application in screening for drug development.
Bifurcation and Stability of Stationary Solutions of the Fitz-Hugh-Nagumo Equations

The Fitz-Hugh-Nagumo equations have been of some interest to both mathematicians and theoretical biologists for several years. The reason for this stems from the fact that they can be considered as a simpler model for the celebrated Hodgkin-Huxley equations, in that they exhibit many of the features of this latter system. Indeed, mathematicians have studied them because their structure is different from the usually encountered equations in physics, and they therefore admit solutions with less familiar properties: homoclinic travelling waves, threshold effects, etc. The equations can be written as
Measurement of nitrogen evolution in a staged oxy-combustion coal flame

Abstract Oxy-combustion is a technology attracting a significant amount of attention because it enables CO 2 capture from the products of coal combustion. Understanding the potential for NO X reduction is a key factor in the economic analysis and design of oxy-combustion systems. In order to better understand NO X formation and destruction in oxy-combustion, measurements of major gas species and nitrogen containing species, NH 3 and HCN, were obtained in a down-fired, premixed, staged, laboratory reactor. The near-burner region was fuel-rich and reducing followed by the addition of burnout oxidizer in order to simulate the staged combustion process of a full-scale boiler. In the vicinity of the burner, gas species measurements were obtained at a resolution of 25 mm. The data show that nitrogen from the coal is rapidly converted to NO X in the first 50–100 mm of the reactor followed by a reduction of NO X in the fuel-rich, near-burner region. NO X increases at the point where burnout oxidizer is added and then remains constant. A slight increase in NO X which is potentially the result of the thermal mechanism in air combustion does not occur in oxy-combustion. In the fuel-rich, near-burner region, stoichiometric ratio (S.R.) = 0.75, oxy-fuel combustion produces more hydrocarbons, NH 3 , and HCN suggesting reburning reactions are more prevalent. Air combustion can be made to produce a similar NO X profile to oxy-combustion by lowering the S.R. (deeper staging) of the fuel-rich region. The minimum NO X achievable is approximately the same for air and oxy-combustion, but the oxy-combustion minimum NO X occurs at a higher S.R. in the fuel-rich zone which allows oxy-combustion to achieve higher carbon conversion for the same NO X reduction. The higher concentrations of NH 3 and HCN seen at a given fuel-rich zone equivalence ratio also suggest recycled NO X may be reduced more efficiently in oxy-combustion than would be expected for air combustion.
POST‐PRISON SUCCESS PREDICTION A Preliminary Florida Study

This preliminary study attempts to prepare the foundations for obtaining a valid predictive measure for the chance of “success” for a prisoner leaving the Florida penal system. A random sample of 200 Florida prison system releases is analyzed from several vantage points Parolee versus expvee popubtion differences are studied and a variant of the California Base Expectancy Scale is constructed for Florida. To overcome the weakness of utilizing the same predictive model for a broad spectrum of prisoners, an attempt is made to describe homo geneous subpopulations. Through the use of cluster analysis, one such subpopulation is identified and predictive ability for this group is shown to be greatly increamd.
The borderline or weakly positive Hybrid Capture II HPV test: A statistical and comparative (PCR) analysis

Abstract Objectives Recent studies have hypothesized that laboratory contamination may influence interpretation of Hybrid Capture II (HCII) human papillomavirus (HPV) detection assay values. Study design To test this hypothesis, 572 consecutive HCII samples were statistically evaluated to test the null hypothesis that cross-well contamination was not present. In addition, 874 consecutive paired samples from patients followed by both HCII and polymerase chain reaction (PCR) analysis were compared. Results A Kendall's tau measure of association among adjacent wells yielded a P value of .016, rejecting the null hypothesis of no contamination. Analysis of relative light unit values between 0.8 and 1.5 rejected the null hypothesis at P = .077. Moreover, PCR positivity was significantly higher for samples with HCII values above 1.5 vs 0.8 to 1.5 (P = .001). Conclusion Cross-well contamination of samples occurs during processing, and may influence interpretation of some borderline positives. The proportion of cases at risk is low (
The impact of substance user treatment participation on legal employment and income among probationers and parolees.

Employment is essential for recovery. But treatment could conflict with work schedules, and employment gains could be short lived. This study examined how employment and income varied during and after treatment, what aspects of treatment impacted on employment, and whether treatment improved income. Baseline and follow-up data were analyzed for 760 probationers and parolees in 11 US cities that participated in the 1992–1995 Drug Abuse Treatment Outcomes Study. Results showed that only residential/inpatient treatment was associated, temporarily, with employment. Retention, compliance, and self-efficacy were correlated to posttreatment employment. However, treatment had no impact on income, which was determined by education and work history.
Direct Governmental Involvement in Defence Contracting: Total-Cycle-Time Effects

ABSTRACT The objective of this research is to assess whether direct governmental involvement has significant effects on Total Cycle Time (TCT) in the defence industry. A major US government defence contractor was chosen for this study, with a replication study at another defence contractor. A network and simulation model was used to test the significance of the data collected. The results of this study will serve as a possible guide to future contractual agreements between government and defence contractors.
Healthy Beginnings Plus: An innovative approach to prenatal care

This article describes an innovative prenatal program developed by the Pennsylvania Depart ment of Public Welfare. The program, Healthy Beginnings Plus, offers an array of educational and counseling services to pregnant women in an effort to improve birth outcomes. The feature element of Healthy Beginnings Plus is the care coordinator, who provides the client with health promotion teaching, home assessments/visitation, and a variety of counseling services. The ar ticle describes the operation of the Healthy Beginnings Plus Program at the Lancaster General Hospital Family Health Service. It further suggests that this full service program may be a cre ative, cost-saving model that other states could replicate to help improve infant outcomes. Key words: prenatal education, maternal child outreach
A comparative study of the observations of high clouds and simulations by an atmospheric general circulation model

The importance of clouds in the upper troposphere (cirrus) for the sensitivity of the Earth's climate e.g., requires that these clouds be modeled accurately in general circulation model (GCM) studies of the atmosphere. Bearing in mind the lack of unambiguous quantitative information on the geographical distribution and properties of high clouds, the simulated distribution of upper tropospheric clouds in a spectral GCM is compared with several satellite-derived data-sets that pertain to high clouds only, for both winter and summer seasons. In the model, clouds are assumed to occupy an entire gridbox whenever the relative humidity exceeds 99%: otherwise the grid box is assumed to be free of cloud. Despite the simplicity of the cloud prediction scheme, the geographical distribution of the maxima in the model's upper tropospheric cloud cover coincides approximately with the regions of the observed maxima in the high cloud amount and their frequency of occurrence (e.g., intertropical convergence zone and the monsoon areas). These areas exhibit a minimum in the outgoing longwave radiation (OLR; Nimbus-7) and are also coincident with regions of heavy precipitation. The model, with its relatively simple cloud formation scheme, appears to capture the principal large-scale features of the tropical convective processes that are evident in the satellite and precipitation datasets, wherein the intense, upward motion is accompanied by condensation and the spreading of thick upper tropospheric layers of high relative humidity and cloudiness in the vicinity of the tropical rainbelt regions.
Ifosfamide in pediatric malignant solid tumors

Ifosfamide/mesna was given to 97 patients who had malignant solid tumors diagnosed before they were 21 years of age. Patients received 1.6 g/m2 ifosfamide daily x 5, given i.v. over 15 min, followed by 400 mg/m2 i.v. mesna at 15 min and 4 and 6 h after ifosfamide. Responses were noted in patients with osteosarcoma, Ewing's sarcoma, rhabdomyosarcoma and other soft-tissue sarcomas, rhabdoid tumor, neuroblastoma, Wilms' tumor, primitive neuroectodermal tumor, retinoblastoma, germ-cell tumors, and B-cell lymphoma. Toxicity included mild to moderate nausea and vomiting, transient, reversible myelosuppression, transient elevations of serum blood urea nitrogen (BUN) and creatinine and liver enzymes, infections, and self-limiting neurotoxicity characterized by changes in mental status, motor dysfunction, cranial nerve palsy, cerebellar dysfunction, and seizures. Neurotoxic symptoms were generally seen in patients who had previously received cisplatin. Ifosfamide is an important alkylating agent that should be combined with other agents in phase II and III trials. Alternate dose schedules should also be investigated.
Mandatory Open Access Publishing for Electronic Theses and Dissertations: Ethics and Enthusiasm.

Abstract This article argues against policies that require students to submit theses and dissertations to electronic institutional repositories. The article counters a variety of arguments often used to justify this practice. In addition, the article reports on the results of an examination of electronic thesis and dissertation policies at more than 150 university libraries and graduate schools, offering a system of criteria and scoring for ranking these policies according to their respect for student copyright and intellectual property.
Radiometry before World War II: measuring infrared and millimeter-wave radiation 1800-1925

I sketch some of the highlights of the neglected early history of radiometry. The only unifying theme is the measurement of infrared and millimeter-wave radiation, with an emphasis on the personalities involved. Although there were virtually no strictly commercial applications of radiometry during the period (unless one counts the making of scientific instruments), many of the investigators also tried their hands at applied research and inventions, with mixed results. However, the first researcher we consider was a good example of the eighteenth-century "gentleman scientist:" William Herschel
Enhancing the Mechanical Properties of Articular Cartilage Through Enzyme-Mediated Collagen Crosslinking as Regulated by Low Oxygen Tension

The poor ability of articular cartilage to repair following disease and injury makes the tissue a key target for reparative and regenerative medicine strategies. It has been shown that human knee joint resides under hypoxic conditions. Oxygen tension in healthy human synovium is between 7 and 11% and in articular cartilage may therefore be as low as 1–2.5% [1].© 2012 ASME
Theory of deliquescence and modified Köhler curves

Abstract The conventional Kohler theory, which describes the equilibrium sizes of hygroscopic aerosol particles in humid air, is modified by considering the solubility limitation so that the deliquescence and hysteresis processes can also be explained. A set of modified Kohler curves was constructed based on the modified theory. The deliquescence, dehydration, and spontaneous crystallization points (relative humidities) that are the characteristics of the aerosol particles can be identified on the modified Kohler curve diagram. These characteristic relative humidities were derived analytically. The relationships between the equilibrium (wet) size, dry size, and the corresponding solute concentration of ammonium sulfate particles were also established for various ambient relative humidities.
TH-E-M100J-03: Early Tumor Response Assessment of Advanced Head and Neck Cancer Using DCE MRI

Purpose: This study investigates whether changes in dynamic contrast enhanced (DCE) MR imaging during the early course of radiation therapy (RT) are correlated with local tumorcontrol in patients with advanced head and neck (H/N) cancer. We hypothesize that an early decrease in tumor perfusion or vascular permeability would be an indicator of early tumor response to RT. Methods: Patients who had newly diagnosed extracranial head and neck cancer and underwent a 7‐week course of definitive chemo‐RT participated in an IRB approved pilot study. Patients had three DCE MRI scans prior to RT, after 2 weeks of RT, and 3 months after the completion of RT. Perfusion parameters of the Gd‐DTPA transfer constant (K represents a combination of blood flow and vascular permeability) and the fractional blood volume (Vp) were estimated using the modified Toft model. Local tumor response was assessed clinically. The association between the changes in perfusion parameters of the tumor during the early course of RT and local tumor responses was analyzed. Results: For the patients in whom complete response was achieved, K in the tumor had the largest reduction, approximately 30%, after 2 weeks of RT compared to prior to RT. However, for the patients whose tumors failed to respond to or partially responded to RT, K in the tumor either increased by ∼80%, or decreased slightly. In contrast, changes in tumor Vp after 2 weeks of radiation were less specific for non‐responders compared to the changes in the tumor K. Conclusion: Preliminary data of this on‐going study suggest that DCE might have potential for early assessment of tumor response to radiation and chemo therapy in advance head and neck cancers.
A Brief Broadband System for Screening Children at Risk for Academic Difficulties and Poor Achievement Test Performance: Validity Evidence and Applications to Practice

The Brief Academic Competence Evaluation Screening System (BACESS) is a broadband universal screening instrument with three increasingly stringent phases for the identification of children at risk for academic and related behavior difficulties. The development of the BACESS involved two samples of students: K–5 students (n = 827) from the standardization sample of the Academic Competence Evaluation Scales (J. C. Diperna & S. N. Elliott, 2000) and a sample of 584 students in Grades 2–5 in 2 South Carolina schools. A total of 29 teachers completed 1 or more phases of the BACESS. The BACESS ratings and students’ year-end standardized achievement test scores were the primary predictor variables in the analyses. The results indicated that the BACESS “Phase 1: Nominations” and “Phase 2: Brief Ratings” correlated significantly with large-scale achievement test results. Phase 1 of the BACESS was a better predictor than Phase 2 across various linear regression models. Teachers perceived BACESS as an effective stru...
A new iterative least-squares method for the extraction of NMR parameters from nonideal powder patterns

Abstract A new approach to fitting powder patterns via nonlinear least-squares analysis is described. This fitting method is designed to be particularly sensitive to the frequencies of important features and insensitive to discrepancies in intensity between calculated and observed spectra. A description of an optimized powder pattern calculation routine is given with a discussion of the calculation of chemical-shift, dipole-coupled chemical-shift, and nonaxially symmetric quadrupolar powder spectra. Examples of fits of chemical-shift and dipole-coupled chemical-shift powder patterns are shown. The potential applications and limitations of the technique are discussed.
Acquisition of avoidance running in the rat

Normative data on avoidance learning of rats in a straight runway are presented. The two-element model of avoidance conditioning is evaluated.
Induction and repression of a puff in Chironomus tentans

Abstract In salivary glands of Chironomous tentans two puffs, I-18-C and IV-2-B, seem to be controlled by the concentration of ecdysone. Toward the end of the molting periods, IV-2-B regresses while I-218-C still is of maximal size. Injection of ecdysone into old prepupae does not reinduce IV-2-B, whereas this locus in larvae of all other stages rapidly responds to the hormone. Hemolymph from old prepupae without IV-2-B induces puffs I-18-C and IV-2-B when injected into last instar intermolt larvae, and thus simulates the effect of injected ecdysone. This ability is not lost by heating the hemolymph to 80°C. Hemolymph from intermolt larvae does not have any effect, whereas hemolymph from very young last instar larvae and from young prepupae apparently has a slight effect on I-18-C, but no effect on IV-2-B. Treatment with cycloheximide results in the reappearance of IV-2-B in old prepupae, although it has no effect on puffing at this locus in larvae of other stages. The effect is prevented by actinomycin D. It is concluded that the titer of ecdysone is high at the end of the pupal molt. This implies that there is an antagonistically acting factor present at this stage which represses IV-2-B. The apparent relationship of this factor to protein syntehsis is considered.
The effects of combinations of heavy metals, hypoxia and salinity on oxygen consumption and carbohydrate metabolism in Crangon crangon (L.) & Carcinus maenas (L.)

The effects of sublethal Cu and Zn levels on the oxygen consumption and carbohydrate metabolism of Crangon crangon (L.) and Carcinus maenas (L.) have been investigated, in combination with the envi...
Further Observations on the Chromosome Morphology of Some Solidago Species

The author presents the chromosome numbers and detailed chromosome morphology of 7 species of the genus Solidago (Asteraceae), the majority of which were collected from the Province of Nova Scotia in Eastern Canada.The somatic chromosomes of Solidago are uniformly characterized by small size (range in length: 2.02 to 2.93 microns) and possess predominantly sub-median to median types of centromeres. The karyotype is generally of the asymmetrical type in which chromosome form a graded series without exhibiting a marked break.Meiotic chromosomes show a regular bivalent formation during diakinesis and at other stages and a normal disjunction at anaphase, suggesting a lack of, or a low degree of interbreeding among these and related species of Solidago. The high degree of pollen fertility observed in these species corroborates this statement.It is concluded that owing to its general uniformity, chromosome morphological data is likely to be of greater value in clarifying the taxonomic status of the higher categories of the family Asteraceae than in differentiating related diploid or polyploid species.
Bridging the Knowledge Gap between Secondary and Higher Education

This article suggests several intersections for possible collaboration among different educational levels and disciplines. It describes some of the collaborative work between a physics teacher and a librarian at a high school level. In particular, science-integrated information literacy competencies have been selected that may easily be mapped to, and extended for, higher education. The paper concludes with directions for further study and a crossover between information literacy standards for secondary schools and colleges.
A virtual vehicle probe model for time-dependent travel time estimation on signalized arterials

Abstract Estimation of time-dependent arterial travel time is a challenging task because of the interrupted nature of urban traffic flows. Many research efforts have been devoted to this topic, but their successes are limited and most of them can only be used for offline purposes due to the limited availability of traffic data from signalized intersections. In this paper, we describe a real-time arterial data collection and archival system developed at the University of Minnesota, followed by an innovative algorithm for time-dependent arterial travel time estimation using the archived traffic data. The data collection system simultaneously collects high-resolution “event-based” traffic data including every vehicle actuations over loop detector and every signal phase changes from multiple intersections. Using the “event-based” data, we estimate time-dependent travel time along an arterial by tracing a virtual probe vehicle. At each time step, the virtual probe has three possible maneuvers: acceleration, deceleration and no-speed-change. The maneuver decision is determined by its own status and surrounding traffic conditions, which can be estimated based on the availability of traffic data at intersections. An interesting property of the proposed model is that travel time estimation errors can be self-corrected, because the trajectory differences between a virtual probe vehicle and a real one can be reduced when both vehicles meet a red signal phase and/or a vehicle queue. Field studies at a 11-intersection arterial corridor along France Avenue in Minneapolis, MN, demonstrate that the proposed model can generate accurate time-dependent travel times under various traffic conditions.
A replication cycle for viroids and other small infectious RNA's

Experimental data concerning viroid-specific nucleic acids accumulating in tomato plants establish, together with earlier studies, the major features of a replication cycle for viroid RNA in plant cells. Many features of this pathway, which involves multimeric strands of both polarities, may be shared by other small infectious RNA's including certain satellite RNA's and "virusoid" RNA's which replicate in conjunction with conventional plant viruses. The presence, in host plans, of an elaborate machinery for replicating these disease agents suggests a role for endogenous small RNA's in cellular development.
The Complex Viral Etiology of St. Augustine Decline

St. Augustine decline is a viral disease of St. Augustinegrass, a turfgrass grown in the Gulf Coast region of the United States. Analyses of 204 plants in two locations in southeast Texas indicate that the disease is caused by an infection with panicum mosaic virus (PMV), alone or in any combination with satellite panicum mosaic virus (SPMV) and/or its satellite RNAs (satRNAs). This is the first report of the incidence of PMV satRNAs in field samples of St. Augustinegrass. Leaf symptoms of plants collected from the field ranged from severe bleaching to a mild chlorotic mottle, but after 5 months in the greenhouse, the plants had a relatively homogeneous chlorotic mottle phenotype, suggesting that environmental conditions have a significant influence on the development of this disease.
Collaborative Learning Comes of Age.

them. I started creating all sorts of exercises for the seminar when I taught it again. It was fun for me and fun for the students. They seemed to be more involved and learning more. So I just kept doing it with my graduate courses. But I never talked to anyone about it. Then when I started teaching undergraduates at the Residential College (RC), a small innovative college at Michigan, I tried using groups with undergraduates. The students took to working together immediately, especially in a course I taught on social science research methods. RC students
Amperometric titration of albumin in blood serum by copper(II)

Abstract Determination of the albumin content of blood surum by amperometric titration with copper(lI) in ammoniacal buffer of pH 9 2 yields values in essential Agreement with, but in general somewhat lower than, those obtained by precipitation in 28% sodium sulfite solution. While the amperometric titration method gives reproducible results of the right order of magnitude, comparison of results with a large number of electrophoretically analyzed samples would be desirable.
A Study of the Relationship between Gender and Online Social Presence

CMC has been considered a â€œdemocratizingâ€ technology; however, research indicates that CMC does not automatically result in social equality, and points to the importance of social and cultural factors surrounding the adoption of technology. Research suggests that CMC may impose a disadvantage to females, demonstrating lower levels of social presence. This study assesses the predictive relationship between gender and online social presence. A total of 395 graduate students participated by responding to the Computer-Mediated Communication Questionnaire. Quantitative research designs and analyses were applied. This study concluded that online social presence is not related to gender; therefore, gender cannot serve as an effective predictor for online social presence. A femaleâ€™s online social presence can be as high as a maleâ€™s. Effective strategies to improve online social presence for both genders are suggested. Additionally, this study raises the importance on gender equity in emerging social media.
Iterative Stable Alignment and Clustering of 2D Transmission Electron Microscope Images

Summary Identification of homogeneous subsets of images in a macromolecular electron microscopy (EM) image data set is a critical step in single-particle analysis. The task is handled by iterative algorithms, whose performance is compromised by the compounded limitations of image alignment and K-means clustering. Here we describe an approach, iterative stable alignment and clustering (ISAC) that, relying on a new clustering method and on the concepts of stability and reproducibility, can extract validated, homogeneous subsets of images. ISAC requires only a small number of simple parameters and, with minimal human intervention, can eliminate bias from two-dimensional image clustering and maximize the quality of group averages that can be used for ab initio three-dimensional structural determination and analysis of macromolecular conformational variability. Repeated testing of the stability and reproducibility of a solution within ISAC eliminates heterogeneous or incorrect classes and introduces critical validation to the process of EM image clustering.
Mechanism of Photosynthesis Decrease by Verticillium dahliae in Potato

Young, visually symptomless leaves from potato (Solanum tuberosum) plants infected with Verticillium dahliae exhibited reduced carbon assimilation rate, stomatal conductance, and intercellular CO2, but no increase in dark respiration, no change in the relationship between carbon assimilation rate versus intercellular CO2, and no change in light use efficiency when intercellular CO2 was held constant. Therefore, the initial decrease in photosynthesis caused by V. dahliae was caused by stomatal closure. Errors in the intercellular CO2 calculation caused by uneven distribution of carbon assimilation rate across the leaf were tested by 14CO2 autoradiography. Patchiness was found at a low frequency. Low stomatal conductance was correlated with low leaf water potentials. Infection did not affect leaf osmotic potentials.
Increase in the urinary excretion of histamine after SRBC immunization of rats

Summary The twenty-four hour urinary excretion of histamine was determined daily in five rats for nine days after sheep red blood cell (SRBC) immunization. Our prior and current studies in rats have shown an increase in splenic and gastric histamine formation by elevated histidine decarboxylase activity after SRBC immunization. The twenty-four urinary excretion of histamine was elevated throughout the period of study with the peak elevation at six days post immunization. These findings after a humoral immune stimulus, as well as prior observations on cellular immunity, suggest the potential value of this noninvasive technic of monitoring urinary histamine in daily estimations of the total body level of histamine formation and release in laboratory and clinical situations in which this type of information may be of value. The increase in the production and release of histamine in immune challenge situations may be an important factor in the increased incidence of gastrointestinal bleeding in patients with renal transplantation, extensive burns with sepsis, and septic shock.
Removal of the vomeronasal organ disrupts the activation of reproduction in female voles

The reproductive system of female prairie voles remains quiescent in the absence of stimulation from males; however, chemosignals from males are capable of at least partially activating female reproduction. In other species, the vomeronasal system mediates some of the reproductive responses of females to males. We found that surgical removal of the vomeronasal organ (VNX) from adult female prairie voles impeded reproductive activation in response to pairing with stud males: ovarian and uterine weights of VNX females paired with stud males for 24 or 60 hours were significantly less than those of normal (NORMAL) or sham-operated (SHAM) females. Furthermore, 8 of 9 NORMAL, 10 of 13 SHAM, but only 4 of 9 VNX females paired with stud males for 60 hours mated. VNX females, however, were still able to use chemosensory cues to locate food. Behavioral observations of females encountering stud males were similar for VNX, SHAM and NORMAL females. We conclude that vomeronasal chemoreception may be a primary component of reproductive activation in female prairie voles, presumably by mediating neuroendocrine responses to chemosignals.
Metal-Dependent Intramolecular Chiral Induction: The Zn(2+) Complex of an Ethidium-Peptide Conjugate.

Ethidium bromide is an aromatic organic dye that for many years has been known to bind via intercalation to the minor groove of DNA. When the ethidium cation binds to DNA, the chirality of the right-handed double helix is imposed upon ethidium (Et), producing induced circular dichroism (ICD). Other examples of ICD have been observed in the heme group of hemoglobin and myoglobin as well as synthetic porphyrin assemblies, and in host−guest assemblies. In every case, an ICD spectrum is produced as a result of the close association of an achiral chromophore with a chiral moiety (e.g., a biopolymer). During the course of our ongoing research into artificial hydrolytic nucleases, we prepared an ethidium−peptide conjugate that displays metal-dependent ICD. Here we report the synthesis and spectroscopic characterization of a metal−peptide assembly which may represent a first example of metal-dependent intramolecular chiral induction.
Microbial degradation of penoxsulam in flooded rice field soils.

The degradation of penoxsulam {2-(2,2-difluoroethoxy)-N-5,8-dimethoxy[1,2,4]triazolo[1,5-C]pyrimidin-2-yl-6-(trifluoromethyl)benzene-sulfonamide} was studied in flasks simulating flooded rice field...
488 IN VITRO SYNTHESIS OF 1,25 DIHYDROXYVITAMIN D3 (1,25) AND 24,25 DIHYDROXYVITAMIN D3, (24,25) BY FETAL (F) AND MATERNAL (M) SHEEP KIDNEYS

Near term ovine pregnancy is characterized by F:M transplacental plasma gradients of 1,25 [70+7 (F) v 48±4 (M) pg/ml. n=19, p<0.001] and 24,25 [1261±189 (F) v 839±74 (M) pg/ml, n=10, p<0.05]. The relative contributions of placental transfer, placental synthesis and fetal synthesis to fetal plasma levels of these metabolites are presently unclear. To further elucidate the role of fetal synthesis, homogenates of fetal and maternal renal cortex were incubated in vitro with 3H-25 hydroxyvitamin D3 (25 OHD3) to assess 25 OHD3-hydroxylase enzyme activities. Products were identified by co-migration on HPLC with authentic 1,25 and 24,25. All data is expressed as mean ± SEM. The predominant metabolite formed by both fetal and maternal tissue was 1,25. There were no differences between fetal and maternal synthesis rates for either 1,25 or 24,25. However, these synthesis rates, when extrapolated to account for differences in 1) maternal and fetal renal mass and 2) maternal and fetal plasma volume, could wholly account for the fetal plasma levels and transplacental gradients of these metabolites observed in vivo.
ALTERNATIVE POLICIES FOR FOREIGN INVESTMENT IN THE PRESENCE OF TARIFF DISTORTIONS

This paper examines two alternative policies for a small, tariff-distorted country hosting foreign investment. One policy is to allow foreign firms to operate behind the tariff wall; the other is to confine them in a free-trade area. Using a specific factor model, the author shows that confining foreign firms in a free-trade area is superior. Furthermore, under that setting, a subsidy to foreign firms on the use of capital is an optimal policy if they can be prevented from paying domestic workers with their own products. Copyright 1985 by Blackwell Publishers Ltd/University of Adelaide and Flinders University of South Australia