cssi/SciSciGPT-SciSciNet huggingface dataset:
Global Asymptotic Stability in a Non-autonomous Difference Equation

Non-autonomous first order difference equation of the form \(x_{n+1}=x_n+a_nf(x_n), n\in \mathbf{N}_0,\) is considered where \(f:\,\mathbf{R}\rightarrow \mathbf{R}\) is a continuous function satisfying the negative feedback assumption \(x f(x)<0, x\ne 0,\) and \(a_n\ge 0\) is a non-negative sequence. Sufficient conditions for the global asymptotic stability of the zero solution are derived in terms of the attractivity of the fixed point \(x_*=0\) under the iterations of distinct maps of the family of one-dimensional maps \(F_{\lambda }(x)=x+\lambda f(x), \lambda \ge 0.\) The principal motivation for consideration of the difference equation and the corresponding family of interval maps comes from a problem of asymptotic behavior in differential equations with piece-wise constant argument (DEPCA).
Examining the Preliminary Effects of a Summer Social Emotional Learning Program for Young Children

This quasi-experimental pilot study examined the use of the Preschool Promoting Alternative Thinking Strategies (PATHS) curriculum during the summer prior to kindergarten entry for preschool-age ch...
A Quality Improvement Project Studying the Integration of a Proposed Diagnostic Algorithm on Inpatient Encephalitis into the Electronic Medical Record and its Impact on Length of Hospital Stay (P4.9-023)

Objective: To establish and study a diagnostic algorithm and inpatient order set for improved evaluation of suspected encephalitis on the neurology inpatient service. Background: Encephalitis is a complex and challenging neurologic disease. Over one hundred viruses can cause encephalitis, along with more newly recognized autoimmune and paraneoplastic etiologies. Given the high morbidity and mortality associated with encephalitis, rapid and accurate diagnosis is important. Design/Methods: We developed a diagnostic algorithm that incorporates CSF and serum testing, MRI findings, travel exposure, seasonality, immunological status, and clinical factors to streamline diagnostic testing in an efficient manner. We built the inpatient diagnostic order set into the EMR and provided educational training to the Neurology Department. The primary outcome measure of this interim analysis was clinical length of stay. Results: 113 patients with encephalitis were identified in this non-implementation patient set with an average clinical length of stay of 26.4 days with a median length of stay of 14.9 days. As of this interim analysis, the order set was used 40 times since it was implemented over a 6 month time period. Of these patients, 15 (35%) had a primary ICD-10 diagnosis associated with encephalitis at the time of discharge. The average clinical length of stay for this patient set was 12.3 days (p value 0.098) with a median length of stay of 4.6 days (p value .0058). Conclusions: This interim analysis demonstrates a statistically significant decrease in the median clinical length of stay (10.3 less days, p value 0.0058). There was also an observed decrease in the average clinical length of stay (14.1 less days), however not statistically significant at the time of this interim analysis due to the number of cases utilizing the order set. There will be ongoing analysis over the next 6 months. Disclosure: Dr. Kaplan has nothing to disclose. Dr. Kresser has nothing to disclose. Dr. Galli has nothing to disclose. Dr. Cho has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Optum. Dr. Clardy has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Adivo Associates (
Condition-Dependent Pd Speciation and NO Adsorption in Pd/Zeolites

Metal ions exchanged on zeolites represent a unique bridge between heterogeneous solid materials and homogeneous inorganic chemistry. The complexing of exchanged metal ions with H2O or NO, is of pa...
Surgical Correction of the "Gummy Smile"

The delineation of excessive gingival display and review of current treatment options. Discussion over periodontal and prosthetic treatments, mucosal stripping procedures, myotomies, Botox therapy, and orthognathic procedures for correction of the "gummy smile."
PuzzledSolutions and sources

Last month (February 2009, p. 104) we posed a trio of brain teasers concerning algorithm termination. Here, we offer some possible solutions. How did you do?
Editorial: A Vision of a Fair and Efficient, Diverse and Inclusive, Cumulative Science of Child Development in the Best and Worst of Times

If you have come here in search of the submission requirements at Child Development, this is perhaps not the editorial you are looking for. Consider visiting instead our revised instructions to authors. Nor does this essay simply detail the priorities of the incoming board and the initiatives we will be implementing over the next 6 years, though these are summarized in Table 1. Rather, this editorial was written to articulate clearly the scientific values underlying current plans and policies at the journal in support of publishing the highest quality and highest impact research on child development. I emphasize two interrelated themes: (a) our plans for continuing to emphasize and enhance diversity and inclusion in research on child development and (b) our policies that remove impediments to cumulative developmental science. Discussion focuses primarily on how we are incentivizing efforts to achieve these widely held yet too often neglected goals, taking as its point of departure emerging challenges to a fair and efficient editorial process at the journal. In so doing, I mean to highlight the essential work of continuously cultivating editorial structures that firmly embed in developmental science fundamental scientific values, principles that make it possible for research on child development to flourish in both the best and worst of times.
Quantitative Investigation of the Process Parameters of Electrohydrodynamic Direct-Writing and Their Effects on Fiber Morphology and Cell Adhesion

Electrohydrodynamic direct-writing (EHD-DW), a "near-field" electrospinning process, is considered as a promising technique to generate nanofibers in a non-contact, continuous, and controllable manner. However, the effect of process parameters on EHD-DW fibers' structures and the effect of fibers' structures on their properties have not yet been fully investigated. In this work, polycaprolactone (PCL) solution was used to fabricate EHD-DW fibers for investigating the process-structure-property correlations of EHD-DW. Three working modes of the electrospinning process and their corresponding regions in the process parameter space were studied. The surface roughness of EHD-DW fibers fabricated at different process parameters was measured. The impact of the surface roughness on the number and morphology of human mesenchymal stem cells (hMSCs) attached to the EHD-DW fibers was investigated. The results suggest that the surface roughness, which can be controlled by the process parameters of EHD-DW, can significantly affect the attachment of hMSCs. The cell density upon seeding can be largely improved by tuning the process parameters to achieve a favorable surface roughness. This work revealed the process-structure-property correlations of EHD-DW technology. Guidelines for controlling the morphology and cellular adhesion of EHD-DW fibers are provided based on the results of this study.
Impact of COVID-19 Pandemic on the Mental Health of Students From 2 Semi-Rural High Schools in Georgia.

Background Concerns have been raised about the consequences of the COVID-19 pandemic on the mental health of adolescents during an important developmental and social period in their lives. This study examines the mental health impact of the pandemic on high school students shortly after closure of public schools in spring 2020, and whether this impact varies by sex, race/ethnicity, socioeconomic status (SES), and grade level. Methods A cross-sectional, one-time online survey was completed by racial/ethnically and socioeconomically diverse students in 9th through 12th grade at 2 semi-rural Georgia public high schools (N = 761). Results Overall, almost one-fourth of high school students were extremely or very worried about the pandemic, with higher rates of worry among students who are racial/ethnic minorities, lower SES, female and in older grades. Results indicated a concerning impact on the stress, anxiety, depression, and loneliness that students are feeling, particularly among girls and those in older grades. Students of color and low SES, who are already disproportionately impacted by COVID-19, are also more likely to experience mental health challenges. Conclusions Findings highlight important demographic differences of the impact of COVID-19 on the mental health of high school students and have implications for schools with addressing these needs.
Short-term volatility forecasting with kernel support vector regression and Markov switching multifractal model

In volatility forecasting literature, Markov switching multifractal (MSM) models are well known for capturing many important stylized facts such as long memory and fat tails. MSM delivers stronger ...
The effects of well damage and completion designs on geoelectrical responses in mature wellbore environments

ABSTRACTWell integrity is one of the major concerns in long-term geologic storage sites due to the potential risk of well leakage and groundwater contamination. Evaluating changes in electrical res...
A comparative study of the genotype profiles of high-risk human papillomavirus infection in male and female HIV-positive patients and their correlation with anal cytology and biopsy.

Introduction: Although anal cancer is more common in women, most of the studies on the role of high-risk human papillomavirus (hrHPV) infection in anal squamous lesions have focused on high-risk male patients. Therefore, we compared the genotype profile and clinicopathologic correlation of hrHPV infection in human immunodeficiency virus-positive (HIV+) men and women. Materials and methods: We retrospectively analyzed 2254 HIV+ patients (1931 men and 323 women) who had undergone anal Papanicolaou tests at our institution; 1189 of them also had follow-up biopsy data available. HPV genotyping was performed using the Roche Cobas system and correlated with the cytologic and histologic diagnosis. Results: Compared with the HIV+ men, the HIV+ women had a significantly lower rate of hrHPV infection (67.5% versus 78.5%; P Conclusions: Although both HIV+ men and HIV+ women have an increased risk of hrHPV infection, HIV+ women have different hrHPV genotype profiles and higher rates of high-grade lesions. Coinfection with different genotypes of hrHPV can significantly increase the risk of HSILs or AIN2-3 in both genders and could requires vigilant clinical and laboratory follow-up.
Plant-predominant eating patterns - how effective are they for treating obesity and related cardiometabolic health outcomes? - a systematic review.

Context The obesity epidemic is a main driver of the chronic disease epidemic; however, present treatment approaches have suboptimal efficacy. Objectives To assess the efficacy of plant-predominant (vegan, vegetarian, plant-based whole foods [PBWFs]) diets in treating obesity and its main cardiometabolic sequelae: hyperlipidemia (HLD); indices of insulin resistance, glycemic control, and diabetes mellitus type 2 (DM2); and cardiovascular disease (CVD), including hypertension (HTN). Data sources A systematic search of multiple databases was conducted for articles published between November 2019 and February 2020; databases searched included: PubMed, Medline (Ovid), Cochrane, CENTRAL, and CINAHL. Data extraction and analysis All interventional trials (randomized controlled trials [RCTs] and trials of non-randomized experimental design) that met the inclusion criteria (English language, duration of at least 4 weeks, primary end point congruent with above objectives, no major flaws in research design that would prevent interpretation) were included in the review. A total of 3135 articles were scanned and 84 were selected. The articles were collated and summarized in 2 evidence tables. Risk of bias for RCTs was assessed using the Cochrane Risk-of-Bias tool 2 as a guide. For non-randomized trials, higher risk of bias was assumed, and the JBI Critical Appraisal tool was used as a guide to determine inclusion. Results Plant-based diets, in general, demonstrated improved weight control and cardiometabolic outcomes related to lipids, cardiovascular end points, blood pressure, insulin sensitivity, A1C, and fasting glucose, and a lower risk of diabetes compared with usual diets and in some cases standard health-oriented diets such as the American Heart Association (AHA), American Diabetic Association (ADA), and Mediterranean diets. Preliminary studies suggest plant-predominant diets practiced as part of healthy lifestyle interventions may stabilize or even reverse DM 2 and CVD. The acceptability and sustainability of plant-predominant diets where measured were generally similar to other health-oriented diets. Conclusion Plant-predominant diets can play a major role in reversing the obesity and chronic disease epidemics. In the setting of sustained lifestyle intervention programs, they may arrest or even reverse DM2 and CVD. Further higher-level RCTs are needed to confirm and expand on these findings.
Effect of a Flipped Classroom Compared With a Traditional Lecture on Physician Assistant Students' Exam Performance.

PURPOSE The purpose of this study was to retrospectively compare the exam performance of physician assistant (PA) students given asthma instruction in a flipped classroom with PA students in a traditional lecture setting while controlling for students' previous academic performance and clinical asthma experience. METHODS Three cohorts of PA students (n = 146) from the years 2017 (traditional-lecture setting) and 2018 and 2019 (flipped-classroom setting) were included in the study. Academic performance across cohorts was compared using answers to 11 exam questions reflective of the asthma content. RESULTS Findings demonstrated significantly greater performance in the flipped classroom compared with traditional lecture. The 2018 and 2019 cohorts scored 9.4% and 13.2% higher, respectively, compared with the 2017 cohort. Exam performance of students with a low likelihood of clinical exposure to asthmatic patients before PA school was similar to those with a high likelihood. CONCLUSION This study found improved exam performance with a flipped classroom. The flipped classroom represents a potential opportunity to maximize similar performances by both less experienced students and more experienced students.
Phase I study of combination of pasireotide LAR + gemcitabine in locally advanced or metastatic pancreatic cancer

Pasireotide LAR (SOM230 LAR) is a cyclohexapeptide engineered to bind to multiple somatostatin receptor subtypes to mimic the action of naturally occurring somatostatin with higher affinity to these receptors than octreotide and is a potent inhibitor of insulin-like growth factor-1 (IGF-1). Somatostatin receptors and IGF receptors are highly expressed in pancreatic cancer, thereby potentially making it a valuable target. This phase I study evaluated safety, tolerability and preliminary tumor response of pasireotide LAR in combination with gemcitabine in locally advanced or metastatic pancreatic cancer. Patients with previously untreated metastatic pancreatic cancer were included. A 3 + 3 dose-escalation design was used. Patients received gemcitabine on days 1, 8 and 15 and pasireotide LAR IM monthly in a 28-day cycle. Two dose levels of pasireotide LAR were planned: 40 mg IM and 60 mg. Cohort was expanded by ten more patients at the highest tested dose to further assess the safety and efficacy. Twenty patients were consented on this trial, and 16 patients were evaluable for safety and efficacy. No dose-limiting toxicities were observed. Two out sixteen patients (12 %) had partial response, and nine of sixteen (56 %) had stable disease as best response. Median progression-free survival was 4.1 months (range 1–16 months), and median overall survival was 6.9 months (range 1–25 months). Most common grade 3 or 4 toxicities were hyperglycemia (n = 5), hyperbilirubinemia (n = 1) and thrombocytopenia (n = 2). Median baseline IGF-1 level was lower in patients with stable disease than in those with progressive disease (63 vs 71 ng/ml). Pasireotide in combination with gemcitabine was well tolerated with disease control rate of 68 %. Larger trials are needed in the future to establish its efficacy in the treatment of pancreatic cancer. NCT01385956.
Performance evaluation of FDDI network and interconnected heterogeneous networks

Interconnected heterogeneous networks are presented and their performance analyzed. The interconnected networks consist of token ring, fiber distributed data interface (FDDI), and carrier sense multiple access with collision detection (CSMA/CD) networks, each of which connects a large population of users. In the interconnected networks, the local users on the token ring send intra- or internetwork packets. The internetwork packets are transmitted to the CSMA/CD network via gateways and the FDDI network. In the meantime, the local users on the FDDI and CSMA/CD networks generate intranetwork packets. Since the maximum packet sizes of these networks are different, packet fragmentation and reassembly are sometimes necessary. These functions are performed by gateways. The model focuses on the end-to-end delay between two end users on the token ring and CSMA/CD network. Analytic models for calculating the delays for the FDDI network and the interconnected networks are presented, and the measurements from the models are compared with that from the simulation models, validating the analytic models. >
Metabolism of nitrilotriacetate by cells of Pseudomonas species.

A Pseudomonas species was isolated from soil which could degrade nitrilotriacetate (NTA) to CO2, H2O, NH3, and cellular constituents without the accumulation of significant quantities of intermediates either in the presence or absence of several inhibitors. After extensive gas chromatography analysis, small quantities of aspartate, glycine, and aconitate were the only detectable compounds to accumulate during NTA degradation, and these compounds were not excreted from the cells. Manometric studies indicated that iminodiacetate, glycine, and glyoxylate are possible intermediates, whereas N-methyliminodiacetate, sarcosine, and acetate are not. The data are consistent with an oxidative cleavage of the C—N bond of NTA as the initial degradation step.
Nonlinear dynamics of connected vehicle systems with communication delays

In this paper, we investigate effects of communication delays on the nonlinear dynamics of connected vehicle systems. Our modeling framework incorporates communication delays, which arise from the intermittency and packet drops in wireless vehicle-to-vehicle communication. Plant stability and string stability are used to characterize the system-level performance of vehicle networks. Delay-dependent stability conditions are derived based on the Lyapunov-Krasovskii theorem and then visualized by using stability diagrams. Numerical simulations are used to validate the stability diagrams and to demonstrate that bistability can be avoided by utilizing the nonlinear stability analysis presented in this paper.
Healthy Worker Effect

Epidemiologic studies of occupationally exposed cohorts are useful in identifying and quantifying environmental risks because workers are generally exposed to higher levels of toxic materials than the general population. Although higher exposures make it easier to detect and characterize modest elevations in risk, such studies are plagued by a particularly pervasive form of selection bias, referred to as the healthy worker effect (HWE). The HWE is reflected in better health status of exposed workers relative to the general population. This bias arises from two sources: (i) workers were initially healthy enough to be hired, whereas the general population includes persons unfit for work, and (ii) workers who stay healthy (survivors) remain exposed, whereas less healthy coworkers reduce exposure via time off work, job transfer, or early termination. Unlike standard methods, G-estimation has been shown to reduce healthy worker survivor bias. Keywords: selection bias; G-estimation; occupational health; statistical methods; time-varying confounders; feedback
Bond graphs, modeling, and simulation in industry: some examples where costly mistakes could have been avoided

In order to develop new concepts into prototypes and ultimately into products, physical system modeling is virtually a necessity. At the concept stage, low order models are needed to understand the interactive dynamics of complex systems, and, as development proceeds into prototyping and manufacture, more sophisticated models may be needed to size components, determine fatigue life, plus more. As the product becomes more and more defined the modeling depends more and more on special purpose software packages that evaluate stress and strain, magnetic circuit design, fluid flow fields, etc. These packages require that the product is near final form, as the input files for these programs require details about the system that would not be known in the concept development stage. The modeling discussed in this paper is specifically directed to the concept development of mechatronic systems. These systems typically involve multiple energy domains where electro-mechanical,pneumatic, and -hydraulic devices are involved. Since the device or system is not well defined at this stage, the modeling must be handled by the inventors using physical principles, and assembling the various pieces of the model into an overall dynamic model that can be simulated. Bond graphs are particularly well suited for concept development of multi-energy domain systems. This is demonstrated here using several examples where modeling at an early stage of development would have avoided some very costly mistakes.
Multi-agent Systems and Distributed Data Mining

Multi-agent systems offer an architecture for distributed problem solving. Distributed data mining algorithms specialize on one class of such distributed problem solving tasks—analysis and modeling of distributed data. This paper offers a perspective on distributed data mining algorithms in the context of multi-agents systems. It particularly focuses on distributed clustering algorithms and their potential applications in multi-agent-based problem solving scenarios. It discusses potential applications in the sensor network domain, reviews some of the existing techniques, and identifies future possibilities in combining multi-agent systems with the distributed data mining technology.
Restricted Maximum Likelihood: Introduction†

Restricted maximum likelihood estimation (REML) aims to maximize likelihood over a restricted parameter space. In a general linear model with multivariate normal error distribution, REML leads to unbiased estimators. Transformation of the data enables the log- likelihood to be split so that variances are estimated from error contrasts. There is a connection with Bayesian methods. The method has been applied to a random-coefficients model for longitudinal data, and to situations where the parameters satisfy order restrictions. Keywords: general linear model; random effects; Bayesian; isotonic; unbiased
Board Structure, Mergers and Shareholder Wealth: A Study of the Mutual Fund Industry

We study mutual fund mergers between 1999 and 2001 to understand the role and effectiveness of fund boards. Some fund mergers - typically across-family fund mergers - benefit target shareholders but are costly to target fund directors. We examine whether certain governance structures relate to whether target boards approve these mergers. Fund mergers of this kind are more likely when funds underperform and when their boards are composed of a larger fraction of independent trustees. This strong interaction effect is consistent with more independent boards exhibiting a lower tolerance of poor performance before initiating across-family mergers. This effect is most pronounced when all of the fund's directors are independent, not at the 75% level of independence required by the SEC. Moreover, while boards approve across-family mergers that lead to substantial reductions in their own compensation, more highly paid target fund boards are less likely to approve these mergers. Other structural board characteristics (in particular, board size and independent chairs) are not strongly related to fund merger likelihoods and board structure is unrelated to post-merger performance.
Efficient Interpolation of High-Fidelity Geopotentials

With a goal of efficiently trading higher-memory footprints for faster runtimes, a high-fidelity interpolation method is presented for approximating a scalar quantity and associated gradients in the global three-dimensional domain external to a sphere. The new “Fetch” interpolation model uses the Junkins weighting function strategy to achieve continuity and smoothness. An overlapping grid strategy ensures a singularity-free domain while minimizing associated memory costs. Local interpolating functions are judiciously chosen with a new adaptive order-based selection of local polynomials that minimizes coefficient storage subject to a radially mapped residual tolerance. Analytic inversions of the normal equations associated with each candidate polynomial allow for rapid solutions to the least-squares process without resorting to the conventional numerical linear system solvers. The gradient and higher-order partial derivatives are computed directly with no memory cost, and they are smooth and continuous to ...
Genes Affecting the Expression of Cytochrome c in Yeast: Genetic Mapping and Genetic Interactions

The four mutant genes, cyc2, cyc3, cyc8 and cyc9, that affect the levels of the two iso-cytochromes c in the yeast Saccharomyces cerevisiae have been characterized and mapped. Both cyc2 and cyc3 lower the amount of iso-1-cytochrome c and iso-2-cytochrome c; whereas, cyc8 and cyc9 increase the amount of iso-2-cytochrome c. The cyc2, cyc3, cyc8 and cyc9 genes are located, respectively, on chromosomes XV, I, II and III, and are, therefore, unlinked to each other and unlinked to CYC1, the structural gene of iso-1-cytochrome c and to CYC7, the structural gene of iso-2-cytochrome c. While some cyc3 mutants are completely or almost completely deficient in cyotchromes c, none of the cyc2 mutants contained less than 10% of parental level of cytochrome c even though over one-half of the mutants contain UAA or UAG nonsense mutations. Thus, it appears as if a complete block of the cyc2 gene product still allows the formation of a residual fraction of cytochrome c. The cyc2 and cyc3 mutant genes cause deficiencies even in the presence of CYC7, cyc8 and cyc9, which normally cause overproduction of iso-2-cytochrome c. We suggest that cyc2 and cyc3 may be involved with the regulation or maturation of the iso-cytochromes c. In addition to having high levels of iso-2-cytochromes c, the cyc8 and cyc9 mutants are associated with flocculent cells and other abnormal phenotypes. The cyc9 mutant was shown to be allelic with the tup1 mutant and to share its properties, which include the ability to utilize exogenous dTMP, a characteristic flocculent morphology, the lack of sporulation of homozygous diploids and low frequency of mating and abnormally shaped cells of α strains. The diverse abnormalities suggest that cyc8 and cyc9 are not simple regulatory mutants controlling iso-2-cytochrome c.
Lateral Pressure Dependence of the Phospholipid Transmembrane Diffusion Rate in Planar-Supported Lipid Bilayers

The dependence of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) flip-flop kinetics on the lateral membrane pressure in a phospholipid bilayer was investigated by sum-frequency vibrational spectroscopy. Planar-supported lipid bilayers were prepared on fused silica supports using the Langmuir-Blodgett/Langmuir-Schaeffer technique, which allows precise control over the lateral surface pressure and packing density of the membrane. The lipid bilayer deposition pressure was varied from 28 to 42 mN/m. The kinetics of lipid flip-flop in these membranes was measured by sum-frequency vibrational spectroscopy at 37°C. An order-of-magnitude difference in the rate constant for lipid translocation (10.9 × 10−4 s−1 to 1.03 × 10−4 s−1) was measured for membranes prepared at 28 mN/m and 42 mN/m, respectively. This change in rate results from only a 7.4% change in the packing density of the lipids in the bilayer. From the observed kinetics, the area of activation for native phospholipid flip-flop in a protein-free DPPC planar-supported lipid bilayer was determined to be 73 ± 12 A2/molecule at 37°C. Significance of the observed activation area and potential future applications of the technique to the study of phospholipid flip-flop are discussed.
The Eye in Bone Marrow Transplantation: I. Clinical Study

• A prospective study of 45 patients undergoing bone marrow transplantation included full ocular examination and pretransplant and posttransplant conjunctival biopsies. The major finding was the development of a severe keratoconjunctivitis sicca syndrome that developed in 20 of the 45 patients and closely correlated with the occurrence of acute graft-v-host disease (GVHD). An acute pseudomembranous conjunctivitis in the fulminant stage of acute GVHD developed in six patients. A further ten patients made up a retrospective assessment of bone marrow transplantation and confirmed these clinical findings.
Effect of allogeneic bone marrow on lethally irradiated thymectomized mice.

SummaryThymectomized and sham-thymectomized mice were lethally X-irradiated and given syngeneic and allogeneic bone marrow. Whereas the irradiated syngeneic chimeras failed to reject allogeneic skin grafts in the absence of the thymus, a secondary graft-versus-host disease developed with equal rapidity in both thymectomized and sham-thymectomized allogeneic chimeras. The possibility that bone marrow precursors of lymphoid tissue differentiate via different routes in irradiated syngeneic and allogeneic chimeras is suggested.
Hemispheric asymmetries in the activation and monitoring of memory errors.

Previous research on the lateralization of memory errors suggests that the right hemisphere’s tendency to produce more memory errors than the left hemisphere reflects hemispheric differences in semantic activation. However, all prior research that has examined the lateralization of memory errors has used self-paced recognition judgments. Because activation occurs early in memory retrieval, with more time to make a decision, other memory processes, like strategic monitoring processes, may affect memory errors. By manipulating the time subjects were given to make memory decisions, this study separated the influence of automatic memory processes (activation) from strategic memory processes (monitoring) on the production of false memories. The results indicated that when retrieval was fast, the right hemisphere produced more memory errors than the left hemisphere. However, when retrieval was slow, the left hemisphere’s error-proneness increased compared to the fast retrieval condition, while the right hemisphere’s error-proneness remained the same. These results suggest that the right hemisphere’s errors are largely due to activation, while the left hemisphere’s errors are influenced by both activation and monitoring.
Order of accuracy of QUICK and related convection-diffusion schemes

This report attempts to correct some misunderstandings that have appeared in the literature concerning the order of accuracy of the QUICK scheme for steady-state convective modeling. Other related convection-diffusion schemes are also considered. The original one-dimensional QUICK scheme written in terms of nodal-point values of the convected variable (with a 1/8-factor multiplying the 'curvature' term) is indeed a third-order representation of the finite volume formulation of the convection operator average across the control volume, written naturally in flux-difference form. An alternative single-point upwind difference scheme (SPUDS) using node values (with a 1/6-factor) is a third-order representation of the finite difference single-point formulation; this can be written in a pseudo-flux difference form. These are both third-order convection schemes; however, the QUICK finite volume convection operator is 33 percent more accurate than the single-point implementation of SPUDS. Another finite volume scheme, writing convective fluxes in terms of cell-average values, requires a 1/6-factor for third-order accuracy. For completeness, one can also write a single-point formulation of the convective derivative in terms of cell averages, and then express this in pseudo-flux difference form; for third-order accuracy, this requires a curvature factor of 5/24. Diffusion operators are also considered in both single-point and finite volume formulations. Finite volume formulations are found to be significantly more accurate. For example, classical second-order central differencing for the second derivative is exactly twice as accurate in a finite volume formulation as it is in single-point.
Evaluation of Pull-Off Tests as a FRP–Concrete Bond Testing Method in the Laboratory and Field

The direct tension pull-off test has gained popularity as a test method used in the laboratory and especially in the field to assess the quality of bond between externally bonded fiber-reinforced polymer (FRP) repair materials and concrete owing to its low cost and simple procedure. However, the small scale and localized nature of the test can lead to high variability in the results. Furthermore, the test does not load the bond in a way that is representative of service conditions. Because of these limitations, satisfactory interpretation of results can be difficult. This paper examines the challenges that may be encountered when analyzing the data obtained during testing, including the high variances. Past research efforts using pull-off tests, and results of recent field and laboratory testing by the authors, are discussed to evaluate the benefits and weaknesses of pull-off tests as a quality control and research tool. The authors conclude that pull-off tests have many drawbacks, and if they are used, great care is needed in their application. It is recommended that if this method is to be used as a quality control procedure in the field, pull-off tests on the concrete alone should be conducted to obtain baseline values, and supplementary tests such as acoustic sounding also be used. For laboratory conditions, it is advised that alternative testing procedures be considered and large sample sizes be used to make statistical validation possible.
The applicability of Beer's law for a broad spectral bandpass

Abstract In this note we show that, by a judicious selection of the wavelength at which absorption measurements are conducted, the familiar Beer's law relation may be properly applied for continuum-type absorbers, in spite of large changes in the absorption coefficient over the range of spectral isolation.
Arsenic encapsulation using Portland cement with ferrous sulfate/lime and Terra-Bond™ technologies - Microcharacterization and leaching studies.

Abstract This work reports the results of an investigation on the treatment and encapsulation of arsenic-containing materials by Portland cement with ferrous sulfate and lime (PFL) and Terra-Bond™, a commercially available patented technology. The arsenic materials included: chromated copper arsenate (CCA)-treated wood materials; scorodite-rich mine tailings from the La Trinidad Mine in California; and a soil/smelter dust mixture from the Anaconda Superfund site spiked with monosodium methyl arsenate (MSMA) to simulate an organoarsenic soil material. SEM/EDS and XRD spectra of PFL treated samples showed similarity across all three waste materials while Terra-Bond treated samples showed predominance of elemental sulfur. SEM/EDS of PFL treated samples showed that calcium was imbedded in the structure while micrographs of Terra-Bond treated samples showed the appearance of an epoxy material on the surface. The epoxy material appears to be responsible for encapsulating and reducing the leachability of arsenic. XANES spectra for the PFL treatment of CCA-containing samples showed that arsenic has a predominant pentavalent form (As + 5), and the PFL treatment process did not alter the arsenic oxidation state. But, distinct differences were observed for XANES spectra of untreated and PFL treated scorodite-rich mine tailing which changed the arsenic coordination structure from a mixture of As (+ 3/+ 5) to exclusively As (+ 5). Both S/S techniques reduced the amount of arsenic released in the leaching tests. Most cases show lower amounts of arsenic released from wastes treated by the Terra-Bond™ technique when compared to the PFL technique. The pH of the solution significantly affected the leachability, with the amount of arsenic released increasing with pH. Sequential extraction results indicate that sodium hydroxide was favorable in releasing arsenic in the mine tailings. This is due to ligand displacement reactions of hydroxyl ions with arsenic species and high pH conditions that prevent the readsorption of arsenic.
Characterization of malignant colon tumors with 31P nuclear magnetic resonance phospholipid and phosphatic metabolite profiles.

Background. To further characterize selected pathologic features on a biochemical level, the authors analyzed the nuclear magnetic resonance metabolite and phospholipid spectra of 30 malignant colon tumors using 31P magnetic resonance spectroscopy. Methods. Eleven individual generic phospholipids were identified in the spectra of 17 phospholipid extracts, and 31 individual phosphatic metabolites were identified in the spectra of 13 perchloric acid extracts. The metabolites and lipids were quantified for statistical intergroup comparisons based on tumor stage, lymph node status, differentiation, mucin production, blood vessel invasion (BVI), and lymphatic vessel invasion (LVI). Results. Significant elevations in the relative concentration of α-glycerol phosphate were noted when comparing AJCC tumor classification (T3 vs. T2, 0.92 ± 0.14 vs. 0.46 ± 0.11, P < 0.009), tumor differentiation (moderately vs. well differentiated, 0.92 ± 0.14 vs. 0.46 ± 0.11, P < 0.009), and BVI (presence vs. absence, 1.03 ± 0.04 vs. 0.68 ± 0.10, P < 0.028) by elastic tissue stain. Among the tissue phospholipids analyzed, the relative concentration of a choline phospholipid was significantly different when comparing moderately and poorly differentiated tumors (6.26 ± 0.56 vs. 3.29 ± 0.30, P < 0.001), T2 and T3 tumors (3.90 ± 0.45 vs. 6.31 ± 0.56, P < 0.009), and mucin-positive vs. mucin-negative tumors (4.46 ± 0.56 vs. 6.83 ± 0.76, P < 0.028). Differences in lymph node status of the cases analyzed in this study (lymph node positive vs. lymph node negative) were noted for tumors with elevated levels of sphingomyelin (8.13 ± 0.40 vs. 6.88 ± 0.16, P < 0.02), diminished levels of phosphatidylinositol (5.25 ± 0.27 vs. 6.38 ± 0.34, P < 0.02), elevated levels of beta-glycerol phosphate (5.30 ± 0.70 vs. 1.20 ± 0.06, P < 0.05), and elevated levels of glycerol 3-phosphoserine (0.48 ± 0.01 vs. 0.23 ± 0.02, P< 0.002). Conclusions. The characteristic differences in the phospholipid and intermediate phosphate metabolite profiles identified through magnetic resonance spectroscopic and histopathologic analysis may provide important information regarding the nature of tumor and cell membrane metabolism. Differences in these profiles may identify markers useful for biologic behavior, provide prognostic information, and characterize the impact of the pathologic features of colon cancer. Cancer 1995; 76:1715–23.
USE OF HABITAT DURING DROUGHT BY THE COMMON MUSKRAT (ONDATRA ZIBETHICUS) IN SOUTHWESTERN OKLAHOMA

Status of the common muskrat (Ondatra zibethicus) in the southern High Plains and western Rolling Plains has remained uncertain due to a scarcity of records. I examined diversity of riparian habitats, frequency of occurrence of habitats, availability of habitats, and use of habitats by muskrats within an irrigation drainage system in southwestern Oklahoma during prolonged drought. Six major habitats were supported in 31 km of drainage channels. These included, in order of descending frequency, emergent cattails, prairie sedge meadow, cattail-forested transition, forest, turf grass, and pioneer mudflat. Of habitats in drainage systems, 60% were available for muskrats as defined by presence of water. Availability differed among habitats; prairie sedge meadow had highest availability and emergent cattails was the lowest in availability. Use of habitats differed significantly among habitats and was driven by availability. RESUMEN—El estatus de las ratas almizcleras (Ondatra zibethicus) en las altiplanicies meridionales y las planicies ondulantes occidentales se ha mantenido incierto debido a la escasez de registros. Examinel a diversidad de habitats riberenos, la frecuencia de ocurrencia de habitats, la disponibilidad de habitats, y el uso de habitats por las ratas almizcleras dentro de un sistema de drenaje de irrigacion en el suroeste de Oklahoma durante un pero ´odo de sequo ´a prolongado. Treinta y un kilometros de canales de drenaje sosteno ´an seis tipos principales de habitat, incluyendo en orden de frecuencia descendiente: anea emergente, juncia de prado, anea en transicion a forestacion, bosque, cesped y marisma pionera. El 60% de los habitats del sistema de drenaje fue clasificado como disponible para las ratas almizcleras de acuerdo a la presencia de agua. La disponibilidad difirioentre los tipos de habitats; la juncia de prado tuvo la disponibilidad mas alta mientras que la anea emergente tuvo la mas baja. El uso de los habitats por las ratas almizcleras variosignificativamente entre los tipos de habitats, y fue determinado por su disponibilidad.
Reflections on Kant’s concept (and intuition) of space

Abstract In this paper, I investigate an important aspect of Kant’s theory of pure sensible intuition. I argue that, according to Kant, a pure concept of space warrants and constrains intuitions of finite regions of space. That is, an a priori conceptual representation of space provides a governing principle for all spatial construction, which is necessary for mathematical demonstration as Kant understood it.
Liquid Precursor Route for Hetero‐epitaxy of Zr(Y)O2 Thin Films on (001) Cubic Zirconia

ZrO[sub 2]-3 mol% Y[sub 2]O[sub 3] single-crystal thin films with multiple variants were epitaxially formed on (100) cubic zirconia substrates. The films were prepared by spin-coating an aqueous zirconium acetate/yttrium nitrate solution onto the cubic zirconia substrates and subsequently heat-treated at temperatures between 1,100 and 1,400C. Electron diffraction and dark-field TEM observations showed that the film has tetragonal symmetry and consists of 50-100 nm variants with their c-axes aligned with one of the three substrate cube axes. Unrelaxed strain energy estimates indicate that the two variants with their c[sub t]-axis parallel to the substrate/thin film interface are energetically favorable.
Characterization of NADPH oxidase 5 expression in human tumors and tumor cell lines with a novel mouse monoclonal antibody

Reactive oxygen species generated by NADPH oxidase 5 (Nox5) have been implicated in physiological and pathophysiological signaling pathways, including cancer development and progression. However, because immunological tools are lacking, knowledge of the role of Nox5 in tumor biology has been limited; the expression of Nox5 protein across tumors and normal tissues is essentially unknown. Here, we report the characterization and use of a mouse monoclonal antibody against a recombinant Nox5 protein (bp 600-746) for expression profiling of Nox5 in human tumors by tissue microarray analysis. Using our novel antibody, we also report the detection of endogenous Nox5 protein in human UACC-257 melanoma cells. Immunofluorescence, confocal microscopy, and immunohistochemical techniques were employed to demonstrate Nox5 localization throughout UACC-257 cells, with perinuclear enhancement. Tissue microarray analysis revealed, for the first time, substantial Nox5 overexpression in several human cancers, including those of prostate, breast, colon, lung, brain, and ovary, as well as in malignant melanoma and non-Hodgkin lymphoma; expression in most nonmalignant tissues was negative to weak. This validated mouse monoclonal antibody will promote further exploration of the functional significance of Nox5 in human pathophysiology, including tumor cell growth and proliferation.
In vitro assays used to measure the activity of topoisomerases.

Topoisomerase assays have evolved from simple catalytic assays such as relaxation and supercoiling to those which help to determine the structure-activity relationships of inhibitory agents such as quinolones and some antitumor agents. Topoisomerase assays have found further use in the detection of enzyme fractions during the purification of topoisomerases as well as in studies of mechanisms of antibacterial, antiparasitic, and antitumor agents
Response of the medalist

IN ACCEPTING this fine gold medal commemorating a distinguished electrical engineer, Benjamin G. Lamme, I am gratefully aware both of the fortunate circumstances which time and again led me down an interesting trail of professional effort and of my enormous indebtedness to others — my associates, teachers, and students at Brooklyn Polytechnic Institute, Columbia, and especially MIT, where I have been privileged to work for nearly 30 years. I am indebted, as well, to a vast historical background of science and engineering, sparkling with such names as Thales of Miletus, Von Guericke, Faraday, and Roentgen.
Thermal stability and electrical characteristics of ultrathin hafnium oxide gate dielectric reoxidized with rapid thermal annealing

Dielectric properties of ultrathin hafnium oxide reoxidized with rapid thermal annealing (RTA) have been investigated. Capacitance equivalent oxide thickness (CET) of 45 A hafnium oxide was scaled down to ∼10 A with a leakage current less than 3×10−2 A/cm2 at −1.5 V (i.e., ∼2 V below VFB). Leakage current increase due to crystallization was not observed even after 900 °C rapid thermal annealing (RTA), but CET did increase after high temperature RTA due to the interfacial layer growth and possible silicate formation in the HfO2 film.
Was Nicolaus the Sophist a Christian

In Progymnasmata 45.9-21, Nicolaus the Sophist uses the Christian word παιδοφόρος (“boy-corrupter”) in its typically Christian pairing with µοιχός (“adulterer”) to express what seems to be a Christian sentiment about avoiding detailed discussion of wicked acts. This suggests that he was a Christian, a possibility that previous scholars have considered but were unable to find evidence for.
Cross-hatching at Silver Spur.

DIAMOND-SHAPED patterns formed by the intersection of two sets of lineaments were reported near the promontory Silver Spur on Hadley Delta, about 20 km south of the Apollo 15 landing site1 (Fig. 1). In discussing possible causes of such patterns, the earlier suggestion2 of hypersonic gas flow was not mentioned by Swann et al.1. Here we point out that omission and also observe that O'Keefe's proposal has recently been put on a more sound basis by Rehfuss's3 calculations on transient lunar winds caused by meteorite impact-vaporization.