cssi/SciSciGPT-SciSciNet huggingface dataset:
Factors in Lysis and Lysis Inhibition by Lambda Bacteriophage

Groman, Neal B. (University of Washington, Seattle). Factors in lysis and lysis inhibition by lambda bacteriophage. J. Bacteriol. 90:1563-1568. 1965.-Induced Escherichia coli strain K-12(lambda112) exhibited lysis inhibition at 37 C but lysed at 44 C when incubated in LB medium lacking NaCl [LB - (NaCl)]. In LB medium containing NaCl, the temperatures for lysis and lysis inhibition were reversed. In contrast, induced K-12(lambda) lysed under all of these conditions. At 37 C, the addition of NaCl to LB - (NaCl) at various times after induction of K-12(lambda112) restored lysis. The degree of lysis decreased the longer the addition was delayed, but partial restoration occurred as late as 150 min postinduction. At 44 C, the addition of salt at various times after induction restored lysis inhibition even after lysis had begun. An attempt was made to correlate the conditions for lysis and lysis inhibition with the behavior of lambda112 endloysin. The enzymatic activities of lambda and mutant lambda112 endolysins were compared under various salt-temperature conditions. Both endolysins were progressively and equally inhibited by increasing concentrations of Na(+), K(+), and Li(+) salts, and exhibited similar relative activities at 24 and 37 C. Both were stable at 37 C in the presence and absence of NaCl, and were inactivated at comparable rates at 44 C. The results indicate that the effect of salt and temperature on lysis and lysis inhibition cannot be explained by their direct effect on lambda112 endolysin.
The Criminal Threat to Democratic Consolidation in Latin America

Drawing on more than 200 original interviews in Guatemala and analysis of data from the LAPOP 2008 survey, I argue that high levels of violent crime may imperil democratic consolidation in Latin America. At the individual level, crime victimization and concern about crime are correlated with support for authoritarianism and heightened levels of political participation. At the elite level, public concern about crime provides rightist politicians an opportunity to re-empower militaries, to enact repressive policing measures, and to expand the military’s role in the provision of domestic security. And at the conceptual level, high levels of crime and pervasive impunity are contributing to a widespread delegitimization of the idea of human rights in Latin America. Should crime rates continue to increase in the region, anti-crime movements and parties could mobilize large numbers of Latin Americans while threatening the quality and durability of democracy in the region.
DNA Microarrays: A Practical Approach. Mark Schena, ed. Oxford: Oxford University Press, 1999, 209 pp., $55.00, paperback. ISBN 0-19-963777-8. Microarray Biochip Technology. Mark Schena, ed. Natick, MA: Eaton Publishing, 2000, 298 pp., $45.95. ISBN 1-881299-37-6. DNA Arrays: Methods and Protocols. Jang B. Rampal, ed. Totowa, NJ: Humana Press, 2001, 264 pp., $89.50. ISBN 0-89603-822-X.

Although all three texts address the topic of microarrays, each has a different focus. The first two are edited by Mark Schena, one of the pioneers in the field of DNA microarrays, whereas the last, and newest, text is edited by Jang Rampal of the Beckman Coulter microarray group. DNA Microarrays: A Practical Approach focuses on methods and procedures that would be used by someone just entering the field of DNA microarrays. It joins the well-known “Practical Approach Series” of publications familiar to many in biomedical sciences. By contrast, Microarray Biochip Technology discusses the technology behind the major instruments and procedures used for DNA microarray analysis and is from Eaton, the publisher of BioTechniques . Finally, DNA Arrays: Methods and Protocols is the most recent publication and joins a rapidly expanding series, “Methods in Molecular Biology”. Although this text contains both procedures and technology assessment, most chapters are not as extensive as those in the books edited by Schena. Although all three books offer insights into this rapidly expanding field, each provides the reader with a different perspective that would satisfy unique needs. Several workers who have made substantial advances in DNA microarrays contributed to this 10-chapter book. Its major theme is providing practical information (some in a recipe format) that illustrates how to perform DNA microarray analyses. The first chapter is an overview of selected techniques and recipes and is cowritten by the Editor and R.W. Davis, another pioneer in the use of microarrays. Chapter 2, authored by an early developer of confocal scanners, addresses issues with confocal laser fluorescence scanning of arrays prepared on glass slides. The next three chapters discuss less-recognized applications of microarrays, such as representational differential analysis, use of oligonucleotide arrays for detection of single nucleotide polymorphisms, and selection of antisense oligomers (the latter two …
Existing Screening Methods for Oral Cancer are Generally Acceptable to Patients in Non-dental Settings.

Article Title and Bibliographic Information A systematic review of patient acceptance of screening for oral cancer outside of dental care settings. Paudyal P, Flohr FD, Llewellyn CD. Oral Oncol 2014 50(10):956–62. Reviewer Virginia J. Dodd, PhD, MPH, RDH Purpose/Question To determine the acceptability of screening for oral cancer outside of dental settings Source of Funding Information not available Type of Study/Design Systematic review Level of Evidence Level 2: Limited quality, patient-oriented evidence Strength of Recommendation Grade Grade B: Inconsistent or limited-quality patient-oriented evidence
Viscous material-filled synthetic defects for vibrothermography

This paper describes a method to create viscous material-filled (VMF) synthetic defects for vibrothermography that, like cracks, delaminations, or disbonds, generate heat when exposed to vibration. Standard synthetic defects used in nondestructive evaluation, such as EDM notches and flat-bottom holes, are not suitable for vibrothermography since they do not generate a measurable amount of heat when vibrated. An array of viscous material-filled synthetic defects can be used to evaluate the vibration field in a structure due to a specific source to determine if local vibration amplitudes are sufficient to detect cracks or other defects in different locations in a structure. These synthetic defects can be used to resolve the long-standing problem of testing vibration coverage in a specimen for vibrothermography. Such defects can be manufactured in a wide range of materials and can aid in probability of detection studies.
A member of the Six gene family promotes the specification of P cell fates in the O/P equivalence group of the leech Helobdella

The lateral ectoderm of the leech embryo arises from the o and p bandlets, two parallel columns of blast cells that collectively constitute the O/P equivalence group. Individual blast cells within this equivalence group become committed to alternative O or P developmental pathways in accordance with their respectively ventrolateral or dorsolateral position (Weisblat and Blair, 1984). We here describe a novel member of the Six gene transcription factor family, Hau-Six1/2A, which contributes to the patterning of these cell fates in the leech Helobdella sp. (Austin). During embryogenesis Hau-Six1/2A expression is restricted to the dorsolateral column of p blast cells, and thus correlates with P cell fate over most of the body's length. Experimental manipulations showed that Hau-Six1/2A expression is induced in p blast cells by the interaction with the adjoining q bandlet. In addition, misexpression of Hau-Six1/2A in the ventrolateral o blast cells by injection of an expression plasmid elicited the dorsolateral P cell fates ectopically. These data imply that Hau-Six1/2A is a component of the molecular pathway that normally distinguishes O and P cell fates within this equivalence group. Genomic analysis revealed that the Six1/2 subfamily has expanded to a total of six genes in Helobdella. The pattern of Hau-Six1/2A expression during later embryogenesis suggested that this gene may have lost ancestral function(s) and/or acquired novel roles in association with the gene duplications that produced this expansion.
A data modeling approach to climate change attribution

Climate modeling and analysis of climate change have largely been based on forward simulation with physical models. We propose here a data centric approach to climate study based solely on the actual observed data. This novel approach utilizes a variety of relevant statistical modeling and machine learning techniques such as spatial-temporal causal modeling and extreme value modeling, and suggests multiple future research directions. We will describe preliminary results using data for North America from CRU, NOAA, NASA, NCDC, and CDIAC, as well as certain technical challenges encountered. It is hoped that this alternative perspective will help uncover new insights, improve aspects of simulation models with known uncertainties, and provide a useful complementary approach to climate study.
Molecular aspects of high polymer fracture as investigated by ESR-technique

The investigation of stress induced chain scission by the electron spin resonance (ESR) technique has led to detailed information on number, location, and production kinetics of molecular fracture points. These data are reported here. The possible impact of these ESR results on existing statistical, mechanical, kinetic, and continuum-mechanical fracture models is discussed.
The IDEA Assessment Tool: Assessing the Reporting, Diagnostic Reasoning, and Decision-Making Skills Demonstrated in Medical Students' Hospital Admission Notes

Construct: Clinical skills are used in the care of patients, including reporting, diagnostic reasoning, and decision-making skills. Written comprehensive new patient admission notes (H&Ps) are a ubiquitous part of student education but are underutilized in the assessment of clinical skills. The interpretive summary, differential diagnosis, explanation of reasoning, and alternatives (IDEA) assessment tool was developed to assess students' clinical skills using written comprehensive new patient admission notes. Background: The validity evidence for assessment of clinical skills using clinical documentation following authentic patient encounters has not been well documented. Diagnostic justification tools and postencounter notes are described in the literature1,2 but are based on standardized patient encounters. To our knowledge, the IDEA assessment tool is the first published tool that uses medical students' H&Ps to rate students' clinical skills. Approach: The IDEA assessment tool is a 15-item instrument t...
Localized Turbulence Suppression and Increased Flow Shear near the q=2 Surface during Internal-Transport-Barrier Formation

Broadband turbulent fluctuations in the plasma density are transiently suppressed when low-order rational q surfaces first appear in negative central magnetic shear plasmas on the DIII-D tokamak, which can lead to the formation of internal transport barriers. Increased localized flow shear is simultaneously observed. It transiently exceeds the measured turbulence decorrelation rate, providing a mechanism to trigger the formation of the transport barrier. This increased flow shear and turbulence suppression propagates radially outward, following the q=2 surface.
Using traceability to support model-based regression testing

Model-driven development is leading to increased use of models in conjunction with source code in software testing. Model-based testing, however, introduces new challenges for testing activities, which include creation and maintenance of traceability information among test-related artifacts. Traceability is required to support activities such as selective regression testing. In fact, most model-based testing automated approaches often concentrate on the test generation and execution activities, while support to other activities is limited (e.g. model-based selective regression testing, coverage analysis and behavioral result evaluation) To address this problem, we propose a solution that uses model transformation to create a traceable infrastructure of test-related artifacts. We use this infrastructure to support model-based selective regression testing.
Discontinuity-capturing finite element formulations for nonlinear convection-diffusion-reaction equations

Abstract Formulations which complement the streamline-upwind/Petrov-Galerkin procedure are presented. These formulations minimize the oscillations about sharp internal and boundary layers in convection-dominated and reaction-dominated flows. The proposed methods are tested on various single- and multi-component transport problems.
Effect of Eleven Years in Earth Orbit on a Mirror Surface

At NASA Lewis Research Center, micrometeoroid impact was simulated by accelerating micron-size particles to h> pervelocities. Any changes in the optical properties of surfaces exposed to this impact were then evaluated. The degradation of optical properties of polished metals and thin metallic films after exposure to this environment was determined as a function of impacting kinetic energy/area. A calibrated sensor, 2000 A Al/stainless steel, was developed to detect the micrometeoroid environment and to evaluate the degradation of the optical properties of thin aluminum films in space. This sensor was flown on OSO III and SERT II, satellites that were launched in 1967 and 1970, respectively. No changes in the optical properties of the highly reflective surface were measured during 11 years in space. The results, as determined by the accuracy of the sensor, indicate that highly reflective surfaces should lose less than 1% of their specular reflectance in near-Earth orbit during 11 years.
Vanishing prostate cancer on radical prostatectomy (RP) in the PSA era: incidence and follow-up data from a cohort of 1,060 patients between 1998 and 2010

Sir: There have been a few studies investigating the incidence and prognostic relevance of the “vanishing cancer” phenomenon in the radical prostatectomy specimen (RP), in particular, in the last decade [1, 2]. We undertook this study to determine incidence and prevalence of “vanishing prostatic adenocarcinoma” at our institution and to correlate the outcome of these patients with histopathology findings. We searched our institutional database and identified a total of 18 patients with no residual cancer out of 1,060 radical prostatectomies performed between 1998 and 2010. Four patients were excluded from the analysis due to preoperative hormonal therapy (three cases) and immunotherapy (one case). In the remaining 14 cases, clinical data including age and PSA levels with biopsy data (highest Gleason score, highest percentage of carcinoma, number of biopsy sites, number of positive biopsy sites, use of immunohistochemistry, and number of previous biopsies) and RP data (number of examined slides, highest Gleason score, percentage of carcinoma, and presence of high-grade prostatic intraepithelial neoplasia) were extracted. In all 14 cases, the radical prostatectomy specimens were submitted entirely. The incidence of the vanishing cancer phenomenon was 1.3% in our series (14/1,060 RPs). Among the 14 RPs studied, residual cancer was not identified in 11 patients despite careful and extensive sampling. Three cases showed microscopic foci of cancer involving less than 0.5% of the tissue. The mean age of the patients was 59.09 (44–75). The total number of biopsy sites ranged from 2 to 14 with a mean of 7. The mean PSA was 5.8 units (3.6–9.0). The Gleason score in
Methylthioadenosine phosphorylase (MTAP) in hearing: gene disruption by chromosomal rearrangement in a hearing impaired individual and model organism analysis.

Genes with a role in the auditory system have been mapped by genetic linkage analysis of families with heritable deafness and then cloned through positional candidate gene approaches. Another positional method for gene discovery is to ascertain deaf individuals with balanced chromosomal translocations and identify disrupted or disregulated genes at the site(s) of rearrangement. We report herein the use of fluorescence in situ hybridization (FISH) to map the breakpoint regions on each derivative chromosome of a de novo apparently balanced translocation, t(8;9)(q12.1;p21.3)dn, in a deaf individual. Chromosomal breakpoints were assigned initially by GTG-banding of metaphase chromosomes and then BAC probes chosen to map precisely the breakpoints by FISH experiments. To facilitate cloning of the breakpoint sequences, further refinement of the breakpoints was performed by FISH experiments using PCR products and by Southern blot analysis. The chromosome 9 breakpoint disrupts methylthioadenosine phosphorylase (MTAP); no known or predicted genes are present at the chromosome 8 breakpoint. Disruption of MTAP is hypothesized to lead to deafness due to the role of MTAP in metabolizing an inhibitor of polyamine synthesis. Drosophila deficient for the MTAP ortholog, CG4802, were created and their hearing assessed; no hearing loss phenotype was observed. A knockout mouse model for MTAP deficiency was also created and no significant hearing loss was detected in heterozygotes for Mtap. Homozygous Mtap-deficient mice were embryonic lethal. © 2007 Wiley-Liss, Inc.
The Global Stability of Walrasian Tâtonnement

Abstract The main result herein is that the Walrasian tâtonnement process for a class of economics that generalizes those studied by Scarf and Hirota is globally stable if and only if the usual boundary conditions are satisfied.
Geographic patterns of industrial innovation in China during the 1990s

This study uses a variety of indicators such as patent grants, new product sales and RD though expenditure on absorbing imported technologies has been marginal. Finally, enterprises are not well integrated with independent R&D institutes regarding their R&D efforts, which indicates that the national innovation system in China is still fragmented.
Review: medical therapy with calcium channel blockers or alpha blockers helps patients to pass urinary stones.

Source Citation Hollingsworth JM, Rogers MA, Kaufman SR, et al. Medical therapy to facilitate urinary stone passage: a meta-analysis. Lancet. 2006;368:1171-9. 17011944
A reversible photochemical alteration of uracil and uridine.

Various lines of evidence (1, 3, 4) have suggested that the primary effect of lethal and mutagenic doses of ultraviolet radiations upon living cells may be partially reversible, or at least compensated within the cell. In connection with a general study of the photochemistry of nucleic acid derivatives, we have discovered that, under certain conditions, the initial photodecomposition product of the pyrimidine, uracil, and the corresponding product of the ribose nucleotide, uridine, may spontaneously revert to the initial substances, uracil and uridine, respectively.
Home-birth emergencies in the US and Mexico: the trouble with transport.

Proponents of the global Safe Motherhood Initiative stress that primary keys to safe home birth include transport to the hospital in cases of need and effective care on arrival. In this article, which is based on interviews with American direct-entry midwives and Mexican traditional midwives, I examine what happens when transport occurs, how the outcomes of prior transports affect future decision-making, and how the lessons derived from the transport experiences of birthing women and midwives in the US and Mexico could be translated into improvements in maternity care. My focus is on home birth in urban areas in Mexico and the US. In both countries, biomedicine and home-birth midwifery exist in separate cultural domains and are based on distinctively different knowledge systems. When a midwife transports a client to the hospital, she brings specific prior knowledge that can be vital to the mother's successful treatment by the hospital system. But the culture of biomedicine in general tends not to understand or recognize as valid the knowledge of midwifery. The tensions and dysfunctions that often result are displayed in midwives' transport stories, which I identify as a narrative genre and analyze to show how reproduction can go unnecessarily awry when domains of knowledge conflict and existing power structures ensure that only one kind of knowledge counts. This article describes: (1) disarticulations that occur when there is no correspondence of information or action between the midwife and the hospital staff; and (2) fractured articulations of biomedical and midwifery knowledge systems that result from partial and incomplete correspondences. These two kinds of disjuncture are contrasted with the smooth articulation of systems that results when mutual accommodation characterizes the interactions between midwife and medical personnel. The conclusion links these American and Mexican transport stories to their international context, describing how they index crosscultural markers, and suggest solutions, for "the trouble with transport."
Endothelin-Converting Enzyme-1 Actions Determine Differential Trafficking and Signaling of Corticotropin-Releasing Factor Receptor 1 at High Agonist Concentrations

CRF receptor 1 (CRF(1)), a key neuroendocrine mediator of the stress response, has two known agonists corticotropin-releasing factor (CRF) and urocortin 1 (Ucn1). Here we report that endothelin-converting enzyme-1 (ECE-1) differentially degrades CRF and Ucn1; ECE-1 cleaves Ucn1, but not CRF, at critical residue Arginine-34/35', which is essential for ligand-receptor binding. At near K(D) agonist concentration (30 nm), both Ucn1- and CRF-mediated Ca(2+) mobilization are ECE-1 dependent. Interestingly, at high agonist concentration (100 nm), Ucn1-mediated Ca(2+) mobilization remains ECE-1 dependent, whereas CRF-mediated mobilization becomes independent of ECE-1 activity. At high agonist concentration, ECE-1 inhibition disrupted Ucn1-, but not CRF-induced CRF(1) recycling and resensitization, but did not prolong the association of CRF(1) with β-arrestins. RNA interference-mediated knockdown of Rab suggests that both Ucn1- and CRF-induced CRF(1) resensitization is dependent on activity of Rab11, but not of Rab4. CRF(1) behaves like a class A G protein-coupled receptor with respect to transient β-arrestins interaction. We propose that differential degradation by ECE-1 is a novel mechanism by which CRF(1) receptor is protected from overactivation by physiologically relevant high concentrations of higher affinity ligand to mediate distinct resensitization and downstream signaling.
Characterization of Interphase Regions Using Atomic Force Microscopy

The use of the atomic force microscope (AFM) to measure surface forces has been developed to optimize its operation as a surface imaging tool. This capability can potentially be extended to evaluate nanoscale material response to indentation. In this paper, a novel technique is used to probe local property changes in multi-component polymer systems. Changes in indentation response in interphase regions are investigated for an adhesive system involving a diffuse polymer-polymer bond and for two composite systems. To date, diamond-tipped probes with effective spring constants of 150 and 310 N/m have been used to investigate polyimide and epoxy resin matrices reinforced by carbon fibers.
Dual layer SrTiO3/HfO2 gate dielectric for aggressively scaled band-edge nMOS devices

We have fabricated TiN/Poly-Si gated MOS devices with SrTiO"3/HfO"2 dual layer gate dielectric. These gate dielectrics show EOT (Equivalent Oxide Thickness) scaling of less than 0.7 nm as well as large V"f"b shift in the nMOS direction after conventional gate first process. A sweet spot is observed for 0.5 nm SrTiO"3 where a band-edge effective work-function is obtained with improved EOT, reduced gate leakage and minimal hysteresis increase. But Sr diffuse into the interfacial layer leads to interface degradation. It is shown that proper PDA (post-deposition anneal) can improve interface quality while maintaining thinner EOT.
Comparative electron microscopic studies on Pseudomonas aeruginosa endotoxin

The endotoxin from Pseudomonas aeruginosa C9 was obtained by five standard methods of extraction for comparative electron microscopic studies. Observation of the five preparations demonstrated the presence of two major types of structures. The first of these was seen in endotoxins prepared by trichloroacetic acid, ethyl ether, hot water, and ethylenediamineteraacetate-lysozyme extraction, and consisted of discrete spherules containing smaller spherules within and having a homogeneous staining centre and rod-like border. The other morphologic type was seen only in preparations obtained by the aqueous phenol technique and consisted of pleomorphic staining material and rodlets. Preparations isolated by trichloroacetic acid extraction by phenol extraction. Loss in structural integrity was encountered upon exposure to polymxin B, colistin sulfate and carbenicillin, but not with other antibiotics tested.
Comparison Between Model Simulations and Field Results for In‐Situ Biorestoration of Chlorinated Aliphatics: Part 2. Cometabolic Transformations

A nonsteady-state model is presented and used in simulating the results of field experiments where chlorinated ethenes were cometabolically degraded by methanotrophic bacteria. In cometabolism, contaminants are degraded fortuitously by microbes growing on a primary substrate, which in this case is methane. The model includes microbial processes of microbial growth, utilization of the electron donor (methane) and the electron acceptor (oxygen), and the cometabolic transformation of the chlorinated ethenes coupled with the transport processes of advection, dispersion, and sorption onto the aquifer solids. Model simulations of the chlorinated ethenes biotransformation resulting from the biostimulation of methanotrophic bacteria agreed well with the field observations. A kinetic model for the cometabolic transformation that included the competitive inhibition by methane was required to match the field observations. The simulations duplicated the cyclic oscillations in concentration of the chlorinated ethenes that resulted from the pulse feeding of methane. Rate-limited sorption and desorption were also required in order to match the extended tailing in the concentration response that was observed along with the pulsed oscillations in the concentration due to competitive inhibition. The kinetic parameters for the cometabolic transformation, derived from model fits to the field observations, differed for the different chlorinated ethenes tested. Vinyl chloride (VC) and trans-dichloroethylene (t-DCE) had the highest biotransformation rate coefficients (k/Ks), which were in the range of methane itself, the primary substrate for methanotrophic growth. Cis-dichloroethylene (c-DCE) and trichloroethylene (TCE) were degraded at rates one and two orders of magnitude lower than methane, respectively. The transformation rate for TCE was consistent with laboratory-derived rates from microbes enriched and isolated from the test zone and grown under conditions that most represented those in the field. The kinetic model also permitted the activation and the deactivation of microbial mass towards the cometabolic transformation, which was based on cell growth and decay, and first-order deactivation.
Role of G(i)alpha2-protein in opioid tolerance and mu-opioid receptor downregulation in vivo.

Although opioid receptors are G-protein coupled, the role that specific G-protein subunits play in the development of opioid tolerance and the regulation of opioid receptor number is not well understood. In the present study, we used a Giα2 antisense oligodeoxynucleotide (ODN) to examine the contribution of Giα2 proteins to μ-opioid tolerance and receptor downregulation in the mouse. Mice were injected intracerebroventricularly (ICV) and into the spinal intrathecal space (IT) for 4–5 consecutive days (30 μg/site/day), with an antisense ODN or a mismatch ODN directed at mRNA for the Giα2 subunit of G-proteins. Controls were treated with dH2O. On the second day of ODN treatment continuous subcutaneous (SC) infusion of etorphine (200 μg/kg/day) or morphine (40 mg/kg/day + 25 mg pellet) was begun. Control mice were implanted with inert placebo pellets. Three days later, pumps and pellets were removed and mice were tested for morphine analgesia or μ-opioid receptor density was determined in whole brain. Etorphine produced significant tolerance (ED50 shift = ∼11-fold) and downregulation of μ-opioid receptors (≈25%). Morphine treatment produced significant tolerance (ED50 shift ≈9-fold), but no μ-opioid receptor downregulation. Antisense treatment reduced Giα2 protein levels in striatum and spinal cord by ∼25%. Giα2 antisense reduced the acute potency of morphine. Giα2 antisense blocked the development of tolerance to morphine treatment and reduced the development of tolerance to etorphine treatment. Antisense did not have any effect on etorphine-induced μ-opioid receptor downregulation. In another experiment, 7-day treatment with morphine or etorphine similarly increased Giα2 mRNA and protein abundance in spinal cord. Overall, these results support an important role for Giα2-protein in the acute effects of opioids and opioid tolerance. However, Giα2 is not required for agonist-induced μ-opioid receptor density regulation in vivo. Synapse 47:109–116, 2003. © 2002 Wiley-Liss, Inc.
Engineered approaches to the stem cell microenvironment for cardiac tissue regeneration

Micro- and nanoscale engineering approaches in medicine have the potential to recreate physiologically relevant stem cell microenvironments to enhance our understanding of stem cell behaviour and bring stem cell therapy closer to fruition. The realization of such advancements will impact a number of therapeutic applications, the most immediate of which may be the repair of heart tissue. Despite profound advances in creating physiologically relevant in vivostem cell niches through the control of biochemical regulatory factors, further synergism of innovative techniques promise to elucidate the impact of a number of physical cues such as stem cell differentiation into cardiac cells, the electromechanical coupling among these cells, and the formation of bioengineered cardiac tissue grafts. This review examines the recent physiologically relevant micro- and nanoengineering efforts that have been made to address these factors. In Sections II and III, we introduce the traditional focuses of stem cell derived cardiac tissue: differentiation directed by transcription factors and structural cues within the stem cell niche. However, the majority of this review, Sections IV–VII, endeavours to highlight innovative and unconventional microscale engineering techniques that have employed topographic, biomaterial, microfluidic, mechanical, electrical, and optical stimulation for stem cell based cardiac tissue engineering.
Workers’ Egalitarianism: ‘Social Contract’ and the Theory of Second-Best

How egalitarian are workers in eastern Europe? Jan Winiecki of the Institute for Labour Economics in Warsaw, argues that opposition to reform is based on fear that cosmetic reforms will only reinforce the inefficiencies of the current system rather than egalitarianism.
To provide or not to provide course PowerPoint slides? The impact of instructor-provided slides upon student attendance and performance

As PowerPoint has pervaded today's college classrooms, instructors have struggled with the issue of whether or not to provide students' with copies of course PowerPoint slides (instructor-provided slides). While students report that such slides assist them academically, many instructors have expressed concerns that these slides encourage absenteeism and classroom passivity. To help assess the academic impact of instructor-provided slides, the present study examined two semesters of students' progress in a communication theory course. Across these semesters, the study charted the relationship between access/use of various types of instructor-provided slides on class attendance and exam performance. In its key findings, the study found that instructor-provided slides had no impact on class attendance and an adverse impact on course performance for students using these slides in their notetaking process. We examined student progress across two semesters comparing three slide conditions: No vs. partial vs. full slides.We measured actual student attendance: Instructor-provided slides had no impact on actual class attendance.We examined student use of partial vs. full slides in class note-taking and studying for exams.Instructor-provided slides adversely impacted student course performance on exam items.There were no differences by academic group (high/med/low GPA) on use of slides.
MEMORY STRATEGIES REPORTED BY OLDER ADULTS FOR EXPERIMENTAL AND EVERYDAY LEARNING TASKS

Semistructured interviews were used to identify memory strategies used by 35 older adults. Five types of tasks were used: paired‐associate learning, free recall, serial recall, rule learning, and reading comprehension. For the first three tasks, two types of materials were developed: experimental and everyday. The nine memory activities were presented separately. Participants were asked to describe the strategies they would use for each activity. Order of presentation for the experimental and everyday materials was counterbalanced. Examination of the frequency data revealed differences in the number and type of strategies reported for the five types of learning tasks. An analysis of variance revealed that the group receiving the three everyday tasks first reported a significantly greater use of strategies on all tasks. These results indicate that the elderly may have limited repertoires of alternative memory strategies and that the types of materials used can significantly affect their performance.
Objective and multidimensional acculturation measures: implications for retailing to Hispanic consumers

Abstract Recent growth of ethnically diverse US and international populations makes these groups especially attractive to retailers. Although acculturation research suggests that Hispanics differ from other ethnic groups, little research has been conducted on such potential differences within the Hispanic community. This study examined acculturation measures as predictors of differences among Hispanic consumers with respect to shopping orientations, attitudes toward retailer attributes, and information source preferences. Compared to objective measures, multidimensional measures more effectively predicted culturally-related phenomenon; whereas, neither measure discerned disparities in global attitudes. Implications for retailers’ use of tailored versus mass market strategies related to Hispanic consumers are discussed.
Theoretical reaction kinetics of reversible polymerization

The kinetics of reversible polymerization of a polymer system without transfer and termination reactions is investigated theoretically. An analytic solution is obtained that enables one to predict the variation of monomer concentration with respect to time in a closed system. When the polymer system reaches equilibrium, three different relationships are derived between the equilibrium monomer concentration and the ceiling temperature under different conditions. The classical relationship by Dainton and Ivin is a special case of the three derived cases.
Covalent composition of collagen fibrils from the dermis of the sea cucumber, Cucumaria frondosa, a tissue with mutable mechanical properties

Abstract Intact collagen fibrils were isolated from the dermis of Cucumaria frondosa by a new method involving exposure to a divalent cation chelator followed by extraction in water. The fibrils have sulfated glycosaminoglycan moieties associated with their surfaces in the middle of the gap zones. The covalently associated constituents of the fibrils include collagen and three glycosaminoglycan-containing molecules. Two of the glycosaminoglycan-containing molecules are proteoglycans that are solubilized by disulfide bond reduction. The third, which is the most abundant of the three, is not solubilized by disulfide reduction, but is solubilized by proteolysis with bacterial collagenase. Molecular collagen was extracted from isolated fibrils by pepsin digestion followed by 1 M NaCl extraction at pH 8. The pepsin-digested collagen was insoluble in acid until it had been separated from the fibril-associated glycosaminoglycans. The purified collagen is an α1 trimer. Polyclonal antibodies to C. frondosa collagen do not cross-react with Eucidaris tribuloides or rat tail tendon collagen.
Growth in a natural population of largemouth bass, Micropterus salmoides Lacepede, as determined by physical measurements and [14C]‐glycine uptake by scales

Growth of largemouth bass, Micropterus salmoides, in Lake Rebecca, Minnesota began in July and was associated with increased food consumption. Decreased maintenance levels and increased food consumption combined to produce maximum growth in September. Body growth and in vitro [14C]-glycine uptake by scales varied similarly after the onset of growth; however, during the pre-growth period, fluctuations in glycine uptake may have reflected physiological changes that were not detected by measurement of scale and body growth, but did relate to feeding activity. Patterns of glycine uptake and scope for growth were positively correlated (r= 0.74, P<0.05), which suggested that uptake may be related to general nutritional state.
Finding semantically similar questions based on their answers

A large number of question and answer pairs can be collected from question and answer boards and FAQ pages on the Web. This paper proposes an automatic method of finding the questions that have the same meaning. The method can detect semantically similar questions that have little word overlap because it calculates question-question similarities by using the corresponding answers as well as the questions. We develop two different similarity measures based on language modeling and compare them with the traditional similarity measures. Experimental results show that semantically similar questions pairs can be effectively found with the proposed similarity measures.
Lithium Difluoro(oxalato)borate as Salt for Lithium-Ion Batteries

Lithium difluoro(oxalato)borate is reported as a salt for high-performance lithium-ion batteries with improved cycle life and power capability. The experimental results showed that lithium difluoro(oxalato)borate, LiC 2 O 4 BF 2 , can be reduced at about 1.7 V vs Li + /Li and forms a robust protective SEI film on the graphite surface, as lithium bis(oxalato)borate does. The lithium-ion cells using lithium difluoro(oxalato)borate-based electrolyte had very good capacity retention at 55°C. The lithium-ion cells using the lithium difluoro(oxalato)borate-based electrolyte had very low interfacial impedance. Therefore, lithium difluoro(oxalato)borate is a promising salt for advanced lithium-ion batteries with improved capacity retention and power capability.
Petrophysical analysis of modern reef rocks

On the basis of original fabric, modern reef rock can be divided into two kinds: 1. skeletal framework reef rock, and 2. particle reef rock. The factors that control the pore-system characteristics and their changes are different in the two kinds. In the skeletal framework reef rock the pore system and its development are mainly controlled by (1) the original skeletal pores, and if, with what, and how these pores are filled; and (2) the nature of cementation. In contrast, the pore system and development of the particle reef rock depends strongly upon the type of particles, form of support, and cementation.
Chromosomal location of genes for gliadin polypeptides in durum wheat Triticum turgidum L.

The chromosomal location of genes was determined for 19 of 30 gliadin bands extracted from seeds of a set of durum wheat (Triticum turgidum L. var. ‘durum’) aneuploids and durum cultivars. Individual bands were identified by their relative mobility on polyacrylamide gels. The gene(s) for gliadin band 45, which has been associated with strong gluten by several authors, was shown to be controlled by chromosome 1 B. A band with similar mobility (band 46) was controlled by ‘Chinese Spring’ chromosome 1D. Conventional breeding procedures coupled with the use of electrophoresis of gliadin polypeptides should result in rapid conversion of current weaker gluten durum cultivars to strong gluten cultivars.
Fatal aspergillosis: an unusual complication of steroid therapy for inflammatory bowel disease

Fatal aspergillosis: an unusual complication of steroid therapy for inflammatory bowel disease
Kynurenine in rat hair.

THE pelage of certain murine rodents contains substantial amounts of fluorescent tryptophan metabolites1. In the laboratory rat l-kynurenine2 is the principal compound present, with relatively small amounts of kynurenic acid, Nα-acetyl-l-kynurenine and other fluorescent compounds. It is interesting to know what drain this constitutes on the total tryptophan pool in the rat3,4; and since tryptophan has been suggested as a possible precursor of red hair pigment, phenomelanin5, how the amounts of kynurenine compare in the hair of rats with different coat colours.
Autokinetic Movement: Selective Manipulation of Directional Components by Image Stabilization

With the retinal image of a 35-minute circular target stabilized against horizontal eye movements, horizontal autokinesis is markedly reduced. It is suggested that this result is consistent with an eye movement interpretation of autokinetic movement, and further, that the response patterns reported here are similar to those that might be expected from recent work describing cortical single unit movement detectors.
Salmon calcitonin in the prevention and treatment of osteoporosis.

Abstract The principal calcitonins used therapeutically are porcine, human (synthetic), salmon (synthetic), and eel. Of these substances, salmon calcitonin is the most potent (Reginster 1991). Injectable forms of salmon calcitonin were first indicated for use in the treatment of Paget's disease in the United States and later received an indication for use in the treatment of postmenopausal osteoporosis. The injectable [intramuscular (IM) or subcutaneous (SC)] formulation of salmon calcitonin, however, has been associated with a high rate of noncompliance in elderly patients. The recently approved nasal-spray formulation has ameliorated the difficulties inherent in parenteral administration and is considered a suitable option as an alternative therapy in patients who are not appropriate candidates for estrogen replacement therapy . (Trends Endocrinol Metab 1997;8:89–92). © 1997, Elsevier Science Inc .
Patchwork: Poor Women’s Stories of Resewing the Shredded Safety Net

Today’s low-income families must patch together their own safety nets from disparate sources of assistance within a context of budget cuts and the growing need for services because of the impact of...
Isotope studies of dolomite formation under sedimentary conditions

Measurements of stable isotope abundances of the carbonate portion of the sediment in Deep Springs Lake, California, indicate the presence of at least three phases: a magnesian calcite, a primary sedimentary dolomite, and a detrital dolomite. The former two have isotopic compositions consistent with precipitation at isotopic equilibrium from waters of the lake area. The measured isotopic fractionation factor between sedimentary dolomite and its interstitial water is 1.0351, which is outside the range possible for calcite-water. This indicates that the dolomite has formed by direct crystallization from solution and not from a caloite precursor without further isotope exchange. Isotopic and X-ray evidence does not support the contention of Petersonet al. (1966) that Deep Springs Lake dolomite crystals grow by means of a calcite-like surface layer.
The risk for acute coronary syndrome associated with atrial fibrillation among ED patients with chest pain syndromes

Abstract Objective We sought to determine if atrial fibrillation is associated with an increased risk for an acute coronary syndrome (ACS) among emergency department (ED) patients with chest pain syndromes. Methods We performed a retrospective analysis of a prospectively collected database on ED patients with chest pain by selecting patients with atrial fibrillation and frequency-matched control subjects without atrial fibrillation. Measured outcomes were acute myocardial infarction (AMI), ACS, and unstable angina (UA). The relative risks of AMI, ACS, and UA associated with atrial fibrillation were calculated. Results One hundred forty patients with atrial fibrillation and 683 matched control subjects were identified. The rates of AMI for the atrial fibrillation and control groups were 11.4% and 10.8%, respectively; those of ACS were 27.9% and 26.7%, respectively; and those of UA were 16.4% and 15.8%, respectively. The relative risks of AMI and ACS did not increase in patients with atrial fibrillation: AMI, 1.05 (95% confidence interval [CI] = 0.63-1.75); ACS, 1.05 (95% CI = 0.78-1.40); and UA, 1.05 (95% CI = 0.6-1.7). Conclusion Among patients presenting to the ED with chest pain syndromes, atrial fibrillation is not associated with an increased risk for AMI, ACS, and UA.
Detection of toxic gases using cermet sensors

New technologies are needed for detection and identification of gaseous species in near-real time. Voltammetry, applied to cermet electrochemical cell microsensors, was shown in this study to be promising in its ability to discern and quantify gases. The miniature cermet cells were fabricated from ceramic, metallic, and metal oxide components, and reacted uniquely with gases and mixtures in the atmosphere. Neural net chemometrics algorithms were used to interpret the waveforms to extract information about the presence and concentration of constituent gases. Results to date have shown that these sensors can correctly identify more than thirty electroactive gases while showing a high tolerance for interferents. A single element sensor can determine gas concentrations from the part per million level to the percentage level while arrays provide even better detection and discrimination. This work focuses on four constituents of diesel exhaust: benzene, 1,3-butadiene, acrolein, and acetaldehyde. Voltammetric sensors demonstrated reproducible responses to four concentrations of each constituent spiked into diesel exhaust.
Quantifier problems beyond uniformity

Abstract An error in the work of W. H. Young is used to show how quantification problems still arose after uniformity was well understood.
Effect of a dietary copper deficiency on plasma fibrinolytic activity in male and female mice

To investigate the effects of a dietary Cu deficiency on plasma fibrinolytic activity, groups (n=16) of adult male and female Swiss-Webster mice were fed Cu-supplemented (8.4 mg Cu/kg) or Cu-deficient (0.3 mg Cu/kg) diets ad libitum with deionized water for 43–49 days. Animals were exsanguinated under pentobarbital anaesthesia; platelet-poor plasma was prepared and assayed for euglobulin clot lysis time (ECLT). Plasma protein C (PC) and antithrombin III (AT-III) activities also were determined. No statistically significant effect of Cu deficiency on either PC or AT-III activity was observed but a highly significant (P<0.001) ECLT prolongation in both male and female deficient mice clearly demonstrated that the physiological clot-lysing mechanism must be impaired in these animals. These results may help to explain the thrombotic sequelae of a dietary Cu deficiency in mice.
Deviation inequality for monotonic Boolean functions with application to the number of k-cycles in a random graph

Using Talagrand's concentration inequality on the discrete cube {0, 1}m we show that given a real-valued function Z(x) on {0, 1}m that satisfies certain monotonicity conditions one can control the deviations of Z(x) above its median by a local Lipschitz norm of Z at the point x. As one application, we obtain a deviation inequality for the number of k-cycles in a random graph.