cssi/SciSciGPT-SciSciNet huggingface dataset:
National Evaluation of Mileage-Based Charges for Drivers: Initial Results

This paper presents initial results and conclusions from the National Evaluation of a Mileage-Based Road User Charge, a 2-year field study conducted by the University of Iowa Public Policy Center. The study, which evaluates technical feasibility and user acceptance of mileage-based charging as a potential replacement for the current motor fuel tax, was authorized by the 2005 Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users, which reauthorized federal transportation funding. This study is the first to examine road user charges on a national and multijurisdictional scale. Approximately 2,650 volunteers from 12 areas throughout the country participated in the study, which concluded in July 2010. The system mileage charges were totaled and apportioned to the federal, state, and local levels with the use of onboard computers installed in participants' vehicles. The onboard computers contained Global Positioning System (GPS) receivers with an associated geographic database to...
Tumour Suppressor Genes

Tumour suppressor genes are a group of genes whose loss contributes to malignancy. The original hypothesis surrounding tumour suppressor genes defined a ‘two-hit’ requirement for mutagenesis; however, it is now known that deletion, silencing or downregulation of one or more genes may lead to cancer formation. There is a growing list of putative tumour suppressor genes, and recently several new candidates were added. Research into apoptosis, or programmed cell death, continues to expand. As pathways for which tumour suppressor genes are responsible become clearer, so do potential therapeutics to capitalise on these targets. A summary of the mechanisms by which tumour suppressor genes may act, the mutations which lead to tumourigenesis, and the clinical implications of these phenomena are presented. Key Concepts: Tumour suppressor genes prevent mutagenesis. Perturbation of tumour suppressor gene function may lead to cancer formation. The first tumour suppressor gene identified was the Rb gene, and mutations in the gene lead to the childhood cancer known as retinoblastoma. Although many tumour suppressor genes require two mutations to cause a loss-of-function, in some cases, downregulation of a single tumour suppressor gene may lead to cancer. The p53 gene is involved in a complex pathway of cell death and cell arrest, and mutations in p53 or other genes in the pathway can lead to the development of cancer. There are several other modulators of tumour formation, including telomeres, adhesion molecules and microRNA, that may function like tumour suppressor genes. Identification of tumour suppressor genes has lead to the development of anticancer therapeutic agents targeted to specific pathways that take advantage of this knowledge. Keywords: oncogene; cancer; tumour; tumour suppressor; p53; apoptosis
Coordination of Earnings, Regulatory Capital and Taxes in Private and Public Companies

This study investigates whether the form of ownership in the life insurance industry (i.e., public, private or mutual) affects the pursuit of capital, earnings, and tax management goals between 1975 and 1991. Results indicate that differences resulting from ownership structure are most pronounced in the area of tax planning. Private stock companies use both policy reserves and reinsurance to manage taxes while public companies, on average, do not appear to manage taxes. I investigate whether the tax planning differences observed appear to be induced by compensation schemes used to control agency costs in public firms, or concerns with stock market interpretations, by studying the tax planning behavior of mutual firms. These firms have diffuse ownership structures, similar to those of public companies, and thus face similar agency problems. But since mutual firms are owned by their policyholders, they are not subject to the stock market concerns that affect public companies. If both private stock and mutual firms manage taxes more aggressively than public companies, the inference is that stock market concerns create the behavioral differences. However, if only private stock companies are aggressive tax managers, differences are more likely to stem from agency costs. My results indicate that mutual firms, like public companies, do not, on average, manage taxes. This outcome is consistent with incentive compensation contracts, designed to control agency costs, at least partly inducing differences in tax management behavior between private and public stock companies. I find support for capital management in all ownership structures. However, the specific tools employed vary across firm type. Private stock companies are more likely to manage capital through adjusting dividends while public companies and mutual firms are more likely to vary reinsurance levels. Mutual firms also used realized gains and losses to manage capital. All firm types appear to use policy reserves and reinsurance to smooth earnings.
An oral communication curriculum for health science professionals

This paper describes an oral communication curriculum developed at Massachusetts College of Pharmacy and Health Sciences for future health care professionals whose first language is not North American English. The paper discuss how the MCPHS curriculum helps these students improve their oral communication proficiency, by assessing the oral skills and threshold proficiency level required to succeed, by measuring the students' oral skills with a specialized rubric, and by using specific exercises adapted from the health sciences curriculum to help these students achieve the level of oral proficiency required of health care professionals.
Biological Conditions and Economic Development: Nineteenth-Century Stature on the U.S. Great Plains.

Average stature is now a well-accepted measure of material and economic well-being in development studies when traditional measures are sparse or unreliable, but little work has been done on the biological conditions for individuals on the nineteenth-century U.S. Great Plains. Records of 14,427 inmates from the Nebraska state prison are used to examine the relationship between stature and economic conditions. Statures of both black and white prisoners in Nebraska increased through time, indicating that biological conditions improved as Nebraska’s output market and agricultural sectors developed. The effect of rural environments on stature is illustrated by the fact that farm laborers were taller than common laborers. Urbanization and industrialization had significant impacts on stature, and proximity to trade routes and waterways was inversely related to stature.
Psychosocial Factors That Contribute to HIV/AIDS Risk Behaviors Among Young Black College Women

African American women are disproportionately burdened by human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). Though African Americans represent only 12% of the population in the United States, more than 54% of HIV-positive women in the United States are of African American descent (Centers for Disease Control and Prevention [CDC], 2003). The bulk of HIV/AIDS research focuses on prevention for high-risk minority women and men who have sex with men, whereas young black college women are ignored as a risk group. Though this group may not have some of the common risk factors associated with HIV/AIDS such as poverty, injection drug use, or low levels of education, they still engage in behaviors that place them at risk for contracting HIV. This article examines risk factors that may explain young black college women's decisions to engage in unsafe sexual practices. It also provides an intellectual context for empirically based and theory-supported interventions geared toward this ...
Predictors of reduced tacrolimus dose and trough level through 36 months post-transplant among 578 adult primary kidney transplant recipients

Background A multivariable linear regression model including baseline and immunosuppression-related predictors of the post-kidney transplant tacrolimus dose/day required for achieving a target tacrolimus trough level of 4–8 ng/mL (currently accepted reduced tacrolimus dosing strategy) would provide a practical guide to clinicians. Methods Using our prospectively followed cohort of 578 adult primary kidney transplant recipients assigned to receive reduced tacrolimus dosing as part of maintenance therapy, we determined the significant predictors of absolute tacrolimus dose (mg), tacrolimus trough level (ng/mL), and dose-adjusted tacrolimus trough level (%/L) during the first 36 months post-transplant. Results Two demographic variables were associated with a significantly higher tacrolimus dose at each post-transplant time analyzed: African American recipient (p < 0.000001) and younger recipient age (p ≤ 0.00009). Use of maintenance corticosteroids was also associated with a significantly higher tacrolimus dose but only during the first 12 months post-transplant (p ≤ 0.002). None of the other baseline variables (or use of sirolimus) were predictive of tacrolimus dose, and none of these factors were associated with the tacrolimus trough level (thus, effective therapeutic drug monitoring was achieved). Results for dose-adjusted tacrolimus trough level were inversely related to the tacrolimus dose findings. Conclusions Significantly higher tacrolimus dosing to achieve the target tacrolimus trough level (lower bioavailability) was required, but only among African Americans, younger recipients, and those receiving maintenance corticosteroids.
Can Afghanistan avoid the Natural Resource Curse

Recent discoveries of significant mineral deposits offer Afghanistan the opportunity to attain a level of economic development sufficient to stabilize that country's volatile security situation while providing Afghans with a reasonable standard of living. Much, however, depends on whether Afghanistan can avoid the “Natural Resource Curse,” an inter-related set of economic and social pathologies that often bedevil resource-endowed countries. In this article, the authors describe the Natural Resource Curse, evaluate the obstacles it raises for Afghan economic development, and offer a strategy to minimize the risks Afghanistan faces in its efforts to exploit its mineral wealth for the benefit of the population.
'[Non] è una somala': Deconstructing African femininity in Italian film

(2009). '[Non] e una somala': Deconstructing African femininity in Italian film. The Italianist: Vol. 29, Film Issue, pp. 175-198.
Covalent DNA modification and the regulation of Mutator element transposition in maize

Analyses of the multiple genomic Mu transposable elements in active Mutator lines with several C-methylation sensitive restriction enzymes indicate that Mu elements are undermodified compared with total maize nuclear DNA. Intercrossing of diverse Mutator lines leads to a discrete hypermodification of the Mu elements in a particular plant concurrent with a loss of mutagenic and transpositional potential. The modification events observed appear to be methylation of cytosine at the 5 position in the sequences 5′-CG-3′ and 5′-CNG-3′. Some potential C-methylation sites in Mu elements show a higher degree of methylation than others. Once established, the modified Mu state, like the loss of Mutator activity, is stable on outcrossing. Crosses between active Mutator lines with unmodified Mu elements and Mutator-loss lines with modified Mu elements show partial maternal dominance for the modification event. Mutator activity may also be lost thorugh outcrossing in a mechanism not associated with any detected modification events.
Recursive Quantum Functions, Avoidable Points, & Shadow Points in Recursive Analysis

Abstract In this paper we summarize our approach and findings in a point-free setting for recursive topology and recursive analysis. Recursive analysis has received intensive attention recently and our approach, while differing from those of other schools, does have connections to them. Here, we also present some of our findings on quantum and total recursive functions on the reals, introduce our classification of nonrecursive points, and remark on the connections between our work and the works of others.
Gab Adapter Proteins as Therapeutic Targets for Hematologic Disease

The Grb-2 associated binder (Gab) family of scaffolding/adaptor/docking proteins is a group of three molecules with significant roles in cytokine receptor signaling. Gabs possess structural motifs for phosphorylation-dependent receptor recruitment, Grb2 binding, and activation of downstream signaling pathways through p85 and SHP-2. In addition, Gabs participate in hematopoiesis and regulation of immune response which can be aberrantly activated in cancer and inflammation. The multifunctionality of Gab adapters might suggest that they would be too difficult to consider as candidates for “targeted” therapy. However, the one drug/one target approach is giving way to the concept of one drug/multiple target approach since few cancers are addicted to a single signaling molecule for survival and combination drug therapies can be problematic. In this paper, we cover recent findings on Gab multi-functionality, binding partners, and their role in hematological malignancy and examine the concept of Gab-targeted therapy.
Caecal metabolites and microbial populations in chickens consuming diets containing a mined humate compound

The objectives of this study were to compare the short-chain fatty acid (SCFA) concentrations, amino acid concentrations and key carbohydrate-fermenting anaerobic bacterial populations in the caeca of chickens consuming either control diets or a mined humate compound (MH; Menefee HumateTM). Dietary MH at concentrations of 0, 5 or 10 g kg−1 did not affect (P ⩾ 0·05) the caecal concentrations of SCFA and amino acids. Regardless of treatment, acetate was found to be the predominant SCFA in the caecum followed by propionate (P < 0·05). MH had no effect on the caecal concentrations of 17 amino acids compared with control birds but, when analysed across treatments, glutamate was found to be the predominant free amino acid in the caecum, followed by alanine (P < 0·05). MH did not significantly influence any of the anaerobic microbial populations but Escherichia coli populations from birds receiving either 10 or 50 g kg−1 MH were between 10 and 100 times greater than control birds (P < 0·05). It appears that MH does not influence concentrations of fermentation acids or amino acids in the caecum but may influence levels of individual microbial populations. © 1998 SCI.
Test of first-principle calculations of charge transfer and electron-hole distribution in oxide superconductors by precise measurements of structure factors

We use an approach in electron diffraction, based on quantitative analysis of diffraction intensity of many reflections as a function of sample thickness, to determine Fourier components of the electron distribution in crystals. For short reciprocal vectors our measured accuracy of the Fourier components is, to our knowledge, far beyond previous achievements. This technique is used to study charge transfer and electron-hole distributions in the high-temperature superconductors ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\mathrm{\ensuremath{\delta}}}$ and ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}.$ Our experimental results agree well with electronic structure calculations.
Technical note : strain-measurement error in a constant-stress rheometer

We describe an error in the strain measurement capability of our Rheometrics Stress Rheometer (RSR). This problem may be common to other constant stress rheometers, and calibrations should be carried out to enable compensation in data analysis. With the RSR a shear stress is applied by a rotating fixture and the resulting shearing motion is measured and recorded
Instability of inhibited replication forks in E. coli

Inhibiting the progress of replication forks in E. coli makes them susceptible to breakage. Broken replication forks are evidently reassembled by the RecBCD recombinational repair pathway. These findings explain a particular pattern of DNA degradation during inhibition of chromosomal replication, the role of recombination in the viability of mutants with displaced replication origin, and hyper-recombination observed in the Terminus of the E. coli chromosome in rnh mutants. Breakage and repair of inhibited replication forks could be the reason for the recombination-dependence of inducible stable DNA replication. A mechanism by which RecABCD-dependent recombination between very short inverted repeats may help E. coli to invert an operon, transcribed in the direction opposite to that of DNA replication, is discussed.
SOME ASPECTS OF X-RAY FLUORESCENCE SPECTROMETERS FOR TRACE ELEMENT ANALYSIS.

Abstract The application of pulsed-light feedback to low energy X-ray spectrometers is discussed with respect to the energy resolution and counting rate performance. The use of a guard-ring detector and appropriate circuits to reduce background counts and thereby enhance sensitivity of X-ray fluorescence analysis is also discussed.
Absorption of fluoride through the oral mucosa of rats

Abstract The oral cavity of rats was isolated by means of ligating the oesophagus. Blood was withdrawn from one group of rats via a carotid catheter and the plasma fluoride concentration was determined before and for 2 hr after the application of sodium fluoride or sodium chloride solutions to their oral mucosa. A marked rise in the plasma fluoride level was noted with the maximum concentration reached within 30–60 min. A second group of rats was used for urinary excretion studies. Urine was collected for 24 hr prior to surgery and the application of the test solutions and for 24 hr after. These animals also had their tracheas cannulated. The amount of urinary fluoride for the 24 hr period was 6–7-fold greater in the fluoride-treated rats than that in the saline controls. The study indicated that fluoride ions from sodium fluoride solutions can be absorbed through rat oral mucosa, but probably at a relatively slow rate.
The Leadership of an Industrial Society

THERE IS NOT A SINGLE AREA of modern society which does not have its clinics. But even if one were alone in pointing to the danger spots of our civilization, the very sensing of a drift in human values in a particular direction should have a bearing upon the reactions of thinking people. For the enduring power of any society is after all in its human values: whatever happens to them is the key to the future of every other aspect of the culture. The ubiquitous clinics of our society point to a problem of action, a problem which has to do with nothing less than the permanence of the industrial culture. This statement of issues differs, of course, in many important ways from that of a number of writers on industrialism. One would expect it to contrast sharply with that of the fanatics of industrialism who think in terms of continuing technological expansion, or of stream-lined markets, or of human ingenuity, or of some other phrase which belongs to the golden days of classic industrialism. One would not expect this statement to diverge widely, however, from that of the socialist movement. For socialists of all fifty-seven varieties speak ominously of the collapse of "the system" and of its replacement by a "new order." But their "new order," whether communist, nationalist or gradualist, involves little change in the basic structure of massed mechanization; in fact, that structure is assumed: the changes, if any, are political and imposed upon it. Thus, Marxian socialism states its case very largely in terms of individual income distribution,
Porous metal–organic framework based on a macrocyclic tetracarboxylate ligand exhibiting selective CO2 uptake

A two-fold interpenetrating microporous metal–organic framework, MMCF-1, has been constructed via the self-assembly of a custom-designed macrocyclic tetracarboxylate ligand and Cd(II), and it exhibits interesting selective uptake of CO2 over N2.
Electric pulse-induced fusion of 3T3 cells in monolayer culture

Swiss mouse 3T3-C2 fibroblasts, grown to confluence in monolayer culture, are shown to fuse when exposed to electric fields. Exposure to five repetitive electric pulses of about 1 kilovolt per centimeter with a duration of 50 microseconds caused approximately 20 percent of the cells to become fused (multinucleate) when 1 millimolar magnesium was present in the medium. The effects of minimum thresholds of field strength, pulse duration, and number of pulses were determined. Cell disruption was observed when the electric field exceeded 2.0 kilovolts per centimeter or the pulse was of longer duration than 120 microseconds.
Percolation segregation of binary mixtures under periodic movement

Three strain rates of 1.0, 0.5, and 0.25 Hz were selected for studying percolation segregation in binary mixtures of urea (spherical) and potash (angular). Mixed binary samples prepared from three mean coarse sizes with their corresponding three and two fines sizes for potash and urea, respectively. Herein, three coarse mean sizes 3675, 3075, and 2580 µm and three mean fine sizes 2180, 1850, and 1550 µm were selected for tests. Percolation segregation in mixed binary sample was quantified using the primary segregation shear cell (PSSC-II). Based on experimental results, the segregated fines mass, normalized segregation rate (NSR) and segregation rate of fines for binary mixtures increased with increasing strain rate from 0.25 Hz to 1.0 Hz. The NSR decreased with decreasing strain rate from 1.0 Hz > 0.5 Hz > 0.25 Hz for size ratios 1.7, 2.0, and 2.4 (p < 0.05). At these three strain rates, for size ratio 2.0, the NSR of coarse size 3675 µm with fines size 1850 µm was smaller than the NSR of coarse size 3075 µm with fine size 1550 µm in the binary mixtures (p < 0.05). At three strain rates of 1.0, 0.5, and 0.25 Hz, the NSR for potash was higher (53%, 56%, and 46%) than the NSR for urea for the same size ratio (p < 0.05).
Suicide and the Jail Environment: An Evaluation of Three Types of Institutions

A sample of 321 jail administrators identified their facilities as being either linear intermittent; podular, indirect supervision; or podular, direct supervision. Logistic regression analysis was ...
Cause of the memory effect in “nickel” electrodes

Abstract Several types of commercial batteries employ the H2NiO2–HNiO2 (or Ni(OH)2–NiOOH) reaction in their positive electrodes. Such batteries often exhibit a so-called “memory effect” in which the available capacity at useful voltages noticeably decreases if they are used under conditions in which they are repeatedly only partially discharged before being recharged. However, if such cells are deeply discharged, the apparently lost capacity can be recovered. It is shown that these phenomena can be rationally explained by considering the reactions in the “nickel electrode” in terms of the thermodynamics of the ternary H–Ni–O system.
Lattice location of implanted As and Sb in silicon after pulsed laser annealing

The substitutional fractions for As and Sb implanted into silicon and subjected to pulsed laser annealing have been determined using ion channeling techniques. Substitutional fractions of 98 to 99% are achieved by laser annealing for both of these dopants at doses up to approximately 1.4 x 10/sup 16//cm/sup 2/. Channeling results are also presented showing the effect of different laser energy densities on the removal of lattice damage and the incorporation of As into substitutional lattice sites.
Differential transcriptional regulation by the α- and γ-catalytic subunit isoforms of cAMP-dependent protein kinase☆

Abstract The Cγ and Cα isoforms of the cAMP-dependent protein kinase (PKA) share 83% identity including all critical catalytic and substrate-binding residues defined to date. Compared to Cα, Cγ has a different substrate specificity and a selective pseudosubstrate specificity, exhibiting inhibition by regulatory subunits, but not by the protein kinase inhibitor. In these studies, Cγ-mediated gene transcription regulation was compared with that of Cα in four cell lines using transient transfection/dual luciferase assays. As compared to Cγ, Cα more efficiently activated a cAMP-response element (CRE)-regulated fragment of the human α-glycoprotein hormone promoter which was coupled to a firefly luciferase reporter gene (pGHα-fluc). This occurred in Cos7, Y1, and Kin8 adrenal cells by 23-, 6.5-, and 1.4-fold, respectively. In contrast, Cγ, but not Cα, activated the Sp1RE-regulated herpes simplex virus thymidine kinase promoter which was coupled to a Renilla luciferase reporter (pTK-rluc). In Sp1-deficient Sf9 cells, pGHα-fluc expression was maintained for both isoforms, but cotransfection with an Sp1 expression plasmid was necessary and sufficient for activation of pTK-rluc expression by Cγ. In all cell lines, cotransfection with a PDK1 expression plasmid enhanced the transcriptional activation of both Cα and Cγ (1.5- to 3-fold), while a catalytically inactive PDK1 mutant (PDK·KD) did not. These results suggest that both Cα and Cγ can activate CRE-responsive genes; however, Cα does so with better efficiency than Cγ. In contrast to Cα, Cγ activates transcription of genes containing pTK-like Sp1RE sites. Activation of different C subunit isoforms can provide a means to diversify cAMP-mediated transcription, possibly affecting cell phenotype.
Collagenolytic activity of snake venom: the absence of collagenolytic activity in the trypsin-like enzyme from Crotalus atrox venom.

Abstract 1. 1. Proteolytic activity in Crotalus atrox venom includes collagenolytic and trypsin-like enzymatic activities. Venom trypsin-like enzyme was purified free from collagenolytic activity by a pH step followed by electrofocusing. 2. 2. Venom trypsin-like enzyme prepared by electrofocusing neither caused a reduction in specific viscosity of collagen solutions nor catalyzed the degradation of the polypeptide chains of collagen. 3. 3. The results demonstrate that individual venom proteases are responsible for the trypsin-like and collagenolytic activity.
Accounting and Litigation Risk: Evidence from Directors' & Officers' Insurance Pricing

We study whether and how financial reporting concerns are priced by insurers that sell Directors’ and Officers’ (D&O) insurance to public firms. As D&O insurers typically assume the liabilities arising from shareholder litigation, the premiums they charge for D&O coverage reflect their assessment of a company’s litigation risk. Using a sample of public firms in the 2001-2004 Tillinghast D&O insurance surveys, we document that firms with lower earnings quality or prior accounting restatements pay higher premiums after controlling for other factors impacting litigation risk. In addition, insurers’ concerns about financial reporting are most evident for firms with restatements that are not revenue or expense related, are greater in the period following the passage of the Sarbanes-Oxley Act of 2002, and are greater for firms with financial reporting problems that linger. Our results are consistent with past restatements being viewed as evidence of chronic problems with a firm’s financial statements. By analyzing archival data, we can also quantify the effects of other determinants of D&O premiums (such as business risk, corporate governance, etc.) identified by Baker and Griffith (2007a) through interviews regarding the D&O underwriting process.
Evolving aspects of liver transplantation for nonalcoholic steatohepatitis.

Purpose of reviewNonalcoholic steatohepatitis (NASH), obesity, and the metabolic syndrome are highly prevalent. NASH, a rare indication for liver transplantation in the early 1990s, is now the third most common indication. This review considers key aspects of the liver transplantation for NASH.Recen
A Sp1 Binding Site of the Tumor Necrosis Factor α Promoter Functions as a Nitric Oxide Response Element

Regulation of gene transcription is an incompletely understood function of nitric oxide (NO). Human leukocytes produce increased amounts of tumor necrosis factor α (TNF-α) in response to NO. This effect is associated with decreases in intracellular cAMP, suggesting that NO might regulate gene transcription through promoter sequences sensitive to cAMP such as cAMP response elements (CRE) and Sp1 binding sites. Here we report that a Sp1 binding site in the TNF-α promoter conveys NO responsiveness. Human U937 cells were differentiated for TNF-α production with phorbol 12-myristate 13-acetate. NO donors and H89, an inhibitor of cAMP-dependent protein kinase increased, while dibutyryl cAMP (Bt2cAMP) decreased TNF-α promoter activity. Deletion or mutation of the proximal Sp1 site, but not the CRE site, abolished the activating effects of NO donors and H89. Further, NO- and H89-mediated increases in TNF-α promoter activity were associated with decreased Sp1 binding. The insertion of Sp1 sites into a minimal cytomegalovirus promoter conferred NO responsiveness, an effect blocked by Bt2cAMP. Mutation of these inserted Sp1 sites prevented this heterologous promoter from responding to NO, H89 and Bt2cAMP. These results identify the Sp1 binding site as a promoter motif that allows NO to control gene transcription.
Interdisciplinary teaching: introductory programming via creative writing

Seizing and retaining student interest in programming is a difficult task. Many students find programming to be a dry and tedious task doable only by students gifted with strong analytical skills. Teaching introductory programming via creative writing begins by connecting the planning, organizing, and detailing of writing a story to the programming process. Creative concepts are taught first and then connected to an equivalent programming concept. Group-oriented activities using art, "Mad-Libs"", "Potato Heads"", and "Legos"" allow students to actively make the connections among the creative concepts, analytical concepts, and programming skills. Students work in pairs. Student pairings are assigned by matching a student with analytical tendencies with a student majoring in one of the humanities disciplines. The pairs apply the concepts and skills by creating stories, designing an animation, and implementing the animation using the Alice programming system. This research recognizes the creative nature of programming, invites students who would not consider studying programming to potentially identify an unrecognized talent, and attempts to develop a new approach for teaching introductory programming. This research and teaching is sponsored by a NSF Grant [11].
A 4-GHz frequency-domain fluorometer with internal microchannel plate photomultiplier cross-correlation.

Abstract We have developed and tested a multifrequency phase/modulation fluorometer based on the Hamamatsu Model R2024U gatable microchannel plate photomultiplier (MCP-PMT), using internal MCP-PMT cross-correlation. This internal mixing is accomplished by biasing and modulating the gating mesh which is located 0.2 mm behind the photocathode. Near the photocathode center, no high-frequency photocurrent modulation was achieved. Within a circular area near the photocathode edge, however, the R2024U allows accurate phase shift and demodulation measurements up to at least 4.5 GHz, the frequency limit of our PMT-modulation amplifier. By mixing immediately after the photocathode, there is no decrease in the time resolution due to transit time spread, and the MCP has to process only low-frequency signals. This means no low-level high-frequency signal voltages have to be handled in this fluorometer, and the problems of RF shielding become much less critical. Also, the effective output impedance of the PMT has been increased, resulting in a 43-dB increase in the PMT output signal power. In principle, more MCPs could be built into the PMT, allowing an improved fluorescence detection limit. We have used the method of reference fluorophores in order to compensate for pronounced PMT color effects, a wavelength-dependent modulation, and a wavelength-dependent time shift. No color correction is required in the case of time-dependent depolarization. The performance of the instrument was verified by measurements of the intensity decay of perylene, which showed a single-exponential decay, and by measurements of the decay of tryptophan in water, which showed a double-exponential decay, as expected. Additionally, we measured a 231-ps decay time for rose bengal in a methanol:water mixture (50:50), and a 183-ps correlation time. This method of detection and mixing could be of particular usefulness in studies of time-dependent photon migration in tissues, which require high modulation frequencies, but do not require the detector to be free of color effects.
Chemical modification of positronium formation at metal surfaces.

We have studied the chemical modification of surface charge using positron charge capture. The positronium energy, intensity, and fraction were determined for oxidation of surfaces of Al(111) and Ni(100) at various oxide coverages. We found that increased positronium production at low oxygen coverage results from pickup of electrons from oxygen orbitals at the surface. From the energy of the extra positronium, the energy of the electron state can be determined relative to the Fermi energy.
Radiometric measurements on non-destructive assay standards fabrication for WIPP Performance Demonstration Program

The Inorganic Elemental Analysis Group of LANL has prepared several different sets of working reference materials (WRMs). These WRMs are prepared by blending quantities of nuclear materials (plutonium, americium, and enriched uranium) with diatomaceous earth. The blends are encapsulated in stainless steel cylinders. These WRMs are being measured as blind controls in neutron and gamma based non-destructive assay (NDA) instruments. Radiometric measurements on the blending homogeneity and verification on a set of sixty-three plutonium based WRMs are discussed in this paper.
Proton magnetic resonance spectroscopy ( 1 H-MRS) in ALS

Establishing the presence of upper motor neuron (UMN) pathology is essential for an accurate and definite diagnosis of ALS. However, clinical identification of UMN dysfunction can be difficult in early disease or if lower motor neuron signs are prominent. A routine technique such as magnetic resonance imaging is usually normal and non-specific. Proton magnetic resonance spectroscopy ( 1 H-MRS) is a non-invasive neuroimaging technique that has successfully demonstrated evidence of neuronal abnormalities in motor regions of the brain in ALS. This review discusses the advantages and limitations of employing 1 H-MRS as an investigative tool in the diagnosis of ALS. (ALS 2000; 1(suppl 2): S7-S16)
The isolation of 2-(2-hydroxy-7-methoxy-1,4-benzoxazin-3-one)β-D-glucopyranoside from Zea mays

Abstract A previously unknown compound, identified as a 1,4-benzoxazinone derivative, was isolated from the roots of corn plants. By comparison with other known 1,4-benzoxazinones and the use of infrared, mass, nuclear magnetic resonance and ultraviolet spectrophotometry and synthetic procedures the newly discovered compound was identified as 2-(2-hydroxy-7-methoxy-1,4-benzoxazin-3-one)β- D -glucopyranoside.
Cell cycle-dependent repair of double-strand DNA breaks in a γ-ray-sensitive Chinese hamster cell

A Chinese hamster cell mutant has been isolated which is extremely sensitive to killing by γ-irradiation in the G1, and early S phases of the cell cycle (LD50 of 20 vs. 250 rads for parent), but which has nearly normal resistance in late S. The mutant cell is able to repair single-stranded DNA breaks introduced by γ-radiation. However, in comparison to its parental cell, the mutant is deficient in the repair of double-stranded DNA breaks produced by γ-irradiation during the sensitive G1-early S period, while in the resistant late S period, the repair is nearly the same for both cell types. This correlation between γ-ray sensitivity and repair strongly suggests that an inability to repair double-strand DNA breaks in G1 is the basis for the hypersensitivity of the mutant to killing by γ-rays in this phase of the cell cycle. It also provides direct evidence in mammalian cells that the ability to repair double-strand DNA breaks induced by ionizing radiation is an important biochemical function in cell survival and supports the hypothesis that unrepaired double-strand breaks are a major lethal lesion in mammalian cells. A plausible explanation for the appearance of the cell cycle phenotype of the mutant is that in normal cells there are at least two pathways for the repair of double-strand breaks, one of which functions primarily in late S phase, and the other, either throughout the cell cycle or only in the G1 and early S phases.
Further Remarks Apropos of the 'Ba'-rom-pa and the Tanguts

The 'Ba'-rom-pa subsect of the Tibetan Buddhist Bka'-brgyud-pa sect played an instrumental role in establishing the cult of Mahākāla at the court of the last Tangut emperors. The cult was a major element in ritual Tibetan Buddhist practices utilised to empower these Tangut emperors in the mundane world. It is from this tradition that the practice of propitiating Mahākāla came to be adopted by the Tangut state's Mongol conquerors. Over the last several years, a number of new sources have become available that detail aspects of the 'Ba'-rom-pa role at the Tangut court. Using them allows for a deeper understanding of the life of Ti-shrī Ras-pa, the last Tibetan imperial preceptor at that court, and of his place in the transmission of teachings that included the explicitly power-oriented Mahākāla instructions transmitted by Rtsa-mi lo-tsā-ba. These sources also cast new light on the existing accounts of the Mongol siege of the Tangut capitol, from a Tibetan perspective, and permit us to make some reasonable i...
Numerical simulations of air–water cap-bubbly flows using two-group interfacial area transport equation

Abstract Knowledge of cap-bubbly flows is of great interest due to its role in understanding of the flow regime transition from bubbly to slug or churn-turbulent flows. One of the key characteristics of such flows is the existence of bubbles in different sizes and shapes associated with their distinctive dynamic natures. This important feature is, however, generally not well captured by many available two-phase flow modeling approaches. In this study, a modified two-fluid model, namely a three-field, two-fluid model, is proposed. In this model, bubbles are categorized into two groups, i.e., spherical/distorted bubbles as Group-1 while cap/churn-turbulent bubbles as Group-2. A two-group interfacial area transport equation (IATE) is implemented to describe dynamic changes of interfacial structure in each bubble group, resulting from intra- and inter-group interactions and phase changes due to evaporation and condensation. Attention is also paid to appropriate constitutive relations of the interfacial transfers due to mechanical and thermal non-equilibrium between the different fields. The proposed three-field, two-fluid model is used to predict the phase distributions of adiabatic air–water flows in a confined rectangular duct. Good agreement between the simulation results from the proposed model and relevant experimental data indicates that the proposed model is promising as an improved computational tool for two-phase cap-bubbly flow simulations in rectangular flow ducts.
The relationship between urban form and station boardings for Bogota's BRT

Abstract Despite emerging evidence about the association between the built environment and travel behavior, the relationship between bus transit demand and urban form remains largely unexplored. By relying on primary and secondary data analyzed with a geographic information system, this paper examines the built environment characteristics related to stop-level ridership for Bogota’s successful bus rapid transit system. After accounting experimentally and statistically for the simultaneity between transit supply, transit demand, and the built environment, we find evidence of the importance of the built environment in BRT station boardings. Specifically, environmental supports for walking and personal and environmental barriers to car use were related to higher BRT boardings. Our results underscore the importance of urban environmental interventions to support transit use.
The stability of host-pathogen interactions of plant disease in relation to biological weed control

Abstract A theoretical analysis was conducted to investigate the dynamics of plant-pathogen interactions for biological weed control. Computer simulation showed that the dynamics of plant-pathogen interactions can be determined by the properties of the pathogen. Pathogens with high levels of virulence may exist in nature in low frequencies due to high extinction rates. Pathogens of this type are suitable for the mycoherbicide strategy. Pathogens with a low level of virulence are frequent and may coexist stably with their host. Good candidates for the classical strategy may be the pathogens with intermediate pathogenicity, which maintain a stable interaction and a high control efficiency. The probability of extinction of a pathogen increases when pathogenicity is greater than a critical value at the intermediate range. The regulation of plant populations through reducing host reproductivity and increasing host mortality has similar results.
Protonic Structure of Molecules. I. Ammonia Molecules

The ammonia molecule is treated in this calculation with the nitrogen fixed and with the electrons and protons described by Slater orbitals. The Hamiltonian includes the kinetic-energy operators of the protons. One minimal basis configuration was used for the electrons, and twenty configurations involving six orthogonal spin orbitals constructed from the $s$, ${p}_{x}$, ${p}_{y}$, and ${p}_{z}$ basis orbitals were used for the protons. Proton delocalization was found to be significant, and the kinetic energies of the protons were found to be about 3 kcal/mole. The calculation yielded a protonic spectrum similar to the electronic spectrum. A ground-state energy of -55.44 hartrees was obtained.
Measurements of the noise spectral power density of photosensitive materials at high spatial frequencies.

A new method of measuring the scattered light to determine the noise spectral power density is described. The technique is shown to be useful at the high spatial frequencies used in holography, beyond the range of the former methods of noise power measurement. Measurements of the grain noise of several photographic emulsions used for holography are presented; they are consistent with a model of emulsions characterized by a transmission correlation length. The measured correlation length of several of the emulsions fit experimentally observed spatial frequency responses. Data on noise power of several other photosensitive materials suitable for holography are also presented.
Jeopardy!: an innovative approach to teach psychosocial aspects of pediatrics.

Abstract Objective Medical educators have used Jeopardy! © game to teach medical knowledge. None has reported using it to teach psychosocial aspects of medicine. Methods As part of a cross-cultural communication curriculum for residents in an urban, medically underserved area, we piloted “Bronx Jeopardy! © ” to teach psychosocial aspects of the surrounding community. We applied the same rules used in the popular game show. Participants were asked to complete a survey to rate the content and format of the training. Results Thirty-four residents participated; 30 (88%) completed the survey. Most reported that the information was new. Almost all reported increased understanding of community diversity, desire to learn more about it, and raised awareness of its challenges and resources. All believed that the session helped dispel negative stereotypes. Regarding format, all participants reported that it built collegiality, stimulated interest, was a fun and effective way to learn, and helped retain information. Conclusion Bronx Jeopardy! © was a fun and effective way to learn about psychosocial aspects of pediatrics. Practice implications Using a gaming format, Bronx Jeopardy! © demonstrated an application of Adult Learning Theory. With an expanding questions bank, the tool can be adapted for teaching this topic in other residency programs.
Inequality in mutation rates of the two strands of DNA.

As the mechanisms for replicating the two strands of duplex DNA differ1 it is, in principle, possible for the mutation rates to differ depending on which strand is being copied. In the absence of selection this would lead to a difference in the measured rate of a particular base substitution, such as T to C, depending on which DNA strand was analysed to determine the rate. Thus a change such as T to C on one DNA strand results from either a direct T-to-C mutation on that strand or an A-to-G mutation on the complementary strand; for the other strand the situation is reversed, and it can be seen that different processes are responsible for the two cases, allowing for asymmetry in substitution rate. We have tested whether such asymmetry indeed occurs by studying equivalent sequences from the β-globin complexes of six species of primate. Our results reveal an asymmetry in substitution rates consistent with predictions based on strand-inequalities in mutation rates. Our sequence comparisons also allow us to make predictions about the positions of replication origins and the replication error rates of one strand relative to the other.
Calcium‐dependence and antagonism of responses to α1‐ and α2‐adrenoceptor agonists in vascular tissues from hypertensive and normotensive rats

Inhibition by D600 (methoxyverapamil) of responses to an alpha 2-adrenoceptor selective agonist, B-HT 920, (6-allyl-2-amino-5, 6, 7, 8-tetrahydro-4H-thiazolo [4, 5-d] azepin dihydrochloride), an alpha 1-adrenoceptor selective agonist, phenylephrine (PE), and a nonselective agonist, noradrenaline (NA), was studied in isolated preparations of the aortae and carotid arteries obtained from young (5-7 weeks) and old (15-17 weeks) hypertensive (SHR) and normotensive (WKY) rats. Maximum responses of WKY tissues to B-HT 920 were the most sensitive, PE-induced responses the least sensitive and maximum responses to NA were intermediate in their sensitivity to inhibition by D600. Sub-maximal responses to NA and PE were not different in their sensitivity to inhibition by D600, but were less sensitive than the responses to B-HT 20. Sub-maximal responses to PE were significantly more sensitive to D600 inhibition than were the maximal responses to this agonist. NA-induced responses of tissues from older SHR were less sensitive to inhibition by D600 when compared to responses in WKY rats. Responses to B-HT 920, in tissues suspended in calcium-free solutions, showed the largest decline compared to NA- and PE-induced responses. We conclude that responses to B-HT 920 largely utilize extracellular calcium. PE- and NA- induced responses mobilize extracellular calcium to varying degrees depending upon the concentration of the agonist employed to elicit the response.
A model of excitation and adaptation in bacterial chemotaxis

Bacterial chemotaxis is widely studied because of its accessibility and because it incorporates processes that are important in a number of sensory systems: signal transduction, excitation, adaptation, and a change in behavior, all in response to stimuli. Quantitative data on the change in behavior are available for this system, and the major biochemical steps in the signal transduction/processing pathway have been identified. We have incorporated recent biochemical data into a mathematical model that can reproduce many of the major features of the intracellular response, including the change in the level of chemotactic proteins to step and ramp stimuli such as those used in experimental protocols. The interaction of the chemotactic proteins with the motor is not modeled, but we can estimate the degree of cooperativity needed to produce the observed gain under the assumption that the chemotactic proteins interact directly with the motor proteins.