cssi/SciSciGPT-SciSciNet huggingface dataset:
When is a single molecule heterogeneous? A multidimensional answer and its application to dynamics near the glass transition

Even for apparently simple condensed-phase processes, bulk measurements of relaxation often yield nonexponential decays; the rate appears to be dispersed over a range of values. Taking averages over individual molecules is an intuitive way to determine whether heterogeneity is responsible for such rate dispersion. However, this method is in fundamental conflict with ergodic behavior and often yields ambiguous results. This paper proposes a new definition of rate heterogeneity for ergodic systems based on multidimensional time correlation functions. Averages are taken over both time and molecules. Because the data set is not subdivided, the signal-to-noise ratio is improved. Moment-based quantities are introduced to quantify the concept of rate dispersion. As a result, quantitative statements about the fraction of the dispersion due to heterogeneity are possible, and the experimental noise is further averaged. The practicality of this approach is demonstrated on single-molecule, linear-dichroism trajectories for R6G in poly(cyclohexyl acrylate) near its glass transition. Single-molecule averaging of these data does not provide useful conclusions [C. Y. Lu and D. A. Vanden Bout, J. Chem. Phys. 125, 124701 (2006)]. However, full-ensemble, two- and three-dimensional averages of the same data give clear and quantitative results: the rate dispersion is 95% ± 5% due to heterogeneity, and the rate exchange is at least 11 times longer than the mean rotation time and possibly much longer. Based on these results, we suggest that the study of heterogeneous materials should not focus on “ensemble” versus “single-molecule” experiments, but on one-dimensional versus multidimensional measurements.
Revisiting positive Equality

This paper provides a stronger result for exploiting positive equality in the logic of Equality with Uninterpreted Functions (EUF). Positive equality analysis is used to reduce the number of interpretations required to check the validity of a formula. We remove the primary restriction of the previous approach proposed by Bryant, German and Velev [5], where positive equality could be exploited only when all the function applications for a function symbol appear in positive context. We show that the set of interpretations considered by our analysis of positive equality is a subset of the set of interpretations considered by the previous approach. The paper investigates the obstacles in exploiting the stronger notion of positive equality (called robust positive equality) in a decision procedure and provides a solution for it. We present empirical results on some verification benchmarks.
CRIMES AND OFFENSES Bail Jumping: Redefine Offenses

The Act expands the crime of misdemeanor bail jumping to include defendants charged with or convicted any misdemeanor who fail to appear as directed. In addition, the Act creates the new offense of out-of-state bail jumping and provides notice procedures applicable to felony, misdemeanor, and out-of-state bail jumping.
The “Hamburger Connection” as Ecologically Unequal Exchange: A Cross‐National Investigation of Beef Exports and Deforestation in Less‐Developed Countries

This study explores Norman Myers's concept of the "hamburger connection" as a form of ecologically unequal exchange, where more- developed nations are able to transfer the environmental costs of beef con- sumption to less-developed nations. I used ordinary least squares (OLS) regression to test whether deforestation in less-developed nations is associ- ated with the vertical flow of beef exports to more-developed nations. An interaction term also examines whether this relationship is more pronounced in Latin American nations, as posited by Myers. The sample includes all nondesert, less-developed nations for which there are available data across all indicators (N = 48). Overall, the results confirm the tested hypotheses. The findings also provide unique contextual support for ecologically unequal exchange theory by demonstrating that unequal trade relationships can operate at the level of a single commodity type. For several decades, the hamburger has been associated with the eradication of tropical forests. Norman Myers coined the phrase the "hamburger connection" in the early 1980s to argue that, "tropical defor- estatio n...w as due toNorth American demand for artificially cheap beef" (Myers 1981:3). Although Myers made this claim nearly 30 years ago, a report issued by the Center for International Forestry Research in 2004 shows that Brazil's growing success as an exporter of beef may be the single greatest cause of current forest loss. Other studies also link expan- sion of beef-export enterprises to increases in deforestation in Honduras, Peru, Costa Rica, Ecuador, El Salvador, Bolivia, and a variety of other nations (Bedoya and Klein 1996; DeWalt 1983; Koop and Tole 1997; Nations and Komer 1983; Wunder 2000). Despite the overwhelming case-study evidence exposing the environmental consequences of a ham- burger connection in particular nations, the current literature lacks a quantitative, cross-national examination of this phenomenon. Recent macro-level studies of deforestation focus on how forest degradation in less-developed nations often takes place through processes of ecologically unequal exchange (e.g., Jorgenson 2006;
Transactions Costs and Readership: An “Open” Letter to Our Readers

Introducing a new co-Editor, new (permanent) journal website, becoming an open access journal, indexing on RePEc, SRSA’s 50 th Anniversary, and more!
Gender‐Based Preferential Selection: Influences of Perceptions of Procedurally Unfair Advantage on Performance and Self‐Evaluations

Gender-based preferential selection is believed to affect self-perceptions of beneficiaries, but the mechanisms by which this occurs have not been fully investigated. An online experiment was conducted with male and female undergraduates (n = 509) in the midwestern United States in which method of selection and gender type of job were manipulated. Hypotheses regarding associations between independent variables, self-efficacy, perceptions of procedural fairness, performance, and self-evaluations were tested. Gender- vs. merit-based selection negatively affected procedural fairness; while procedural fairness perceptions related positively to post-hire self-evaluations, in part through performance. Job gender type interacted with applicant gender to affect pre-hire self-efficacy, but self-efficacy did not moderate the relationship between procedural fairness perceptions and post-hire performance. Implications for affirmative-action programs are discussed.
Organic Synthesis Using Metal-Mediated Coupling Reactions

This article provides an overview of the cross-coupling protocols most commonly used in organic synthesis. Particular emphasis is placed upon topics likely to be of interest to the inorganic chemist, namely, history, catalyst development, and mechanistic studies. While not a comprehensive review, this treatment is intended to provide the reader with a summary of some successful catalyst design strategies, methodological improvements, and mechanistic insights that have been achieved over the past 10 years. Keywords: cross coupling; catalysis; palladium; nickel; mechanism; methodology
Site Specific Controls on Wind and Wave Processes and Beach Mobility on Estuarine Beaches in New Jersey, U.S.A.

Data for eight low-energy meso-tidal sand beaches in developed communities on Raritan Bay and Delaware Bay estuaries in New Jersey. U.S.A., are compared to identify the influence of shoreline orientation, sheltering by adjacent headlands, slope and width of the low tide terrace, and human modification on beach processes and responses. Data on these controls, derived from charts and air photos, are used to explain statistically significant similarities and differences in wind and wave characteristics and beach mobility derived from field investigations. Wind conditions were similar on both bays, but processes and responses differed between sites. Shoreline orientation affects the degree to which refracted ocean waves alter the incident wave field, and sites farther from the ocean may have more conspicuous ocean wave influences than sites closer to the ocean. Site specific differences in the width and slope of the low tide terrace have pronounced effects on wave height and mobility of the upper foreshore. Sheltering by natural headlands appears to be less effective than human controls. Compartmentalization of 8 beach by structures can increase or decrease beach mobility, depending on position relative to the ends of a longshore drift compartment. Localized human impacts can have conspicuous effects on low-energy estuarine beaches that undergo limited profile change under natural conditions.
l-Amino acid oxidase. III. Substrate substituent effects upon the reaction of l-amino acid oxidase with phenylalanines☆

Abstract A study was made of the effect of electron withdrawing and donating substituents of a series of phenylalanine substrates on the component steps of the reduction of l -amino acid oxidase ( l -amino acid: O 2 oxidoreductase (deaminating), EC I.4.3.2) by substrate. As reported earlier, the reduction process involves a very rapid initial formation of a transient, spectrophotometrically distinct intermediate followed by the rapid decay of this intermediate into the fully reduced enzyme. Also observed was the slow intermediate decay reported earlier. The reaction was studied anaerobically by the combination of enzyme and substrate by stopped-flow techniques, and in turnover using a Clark oxygen electrode. The overall second-order rate constant for the reduction process in turnover gave a linear Hammett plot with a ϱ value of +0.2 for the phenylalanine substituents having σ values between −0.66 and +0.78. A similar ϱ value of +0.25 was obtained from a Hammett plot for the rapid decay of the transient intermediate into the fully reduced enzyme. The Hammett plot for the formation of the transient intermediate was biphasic in nature. The ascending segment of this Hammett plot gave a ϱ value of +0.7, whereas a negative curvature of the plot was observed for substituents with σ values greater than zero. The experimental results are consistent with the formation of the transient intermediate involving a proton transfer from the substrate α-position and electron transfer to the flavin. Earlier proposed mechanisms for flavin reduction processes are reviewed and discussed and a detailed mechanism for the enzymatic reduction process is proposed which is consistent with available experimental data.
Developmental expression and hormonal regulation of the nuclear 29 kDa juvenile hormone-binding protein in Manduca sexta larval epidermis

We have utilized a high specific activity photoaffinity analog of methoprene, [3H]-methoprene diazoketone (MDK), to study the developmental expression and hormonal regulation of the 29 kDa juvenile hormone (JH)-binding protein. The 29 kDa MDK-binding protein was detected in the epidermis of the feeding 4th and 5th instar larvae but decreased in abundance during the molts to the 5th instar and the pupa. This protein was also detected in day 1 pupal epidermis. Culturing of day 2 5th instar larval integument in the presence of 2 × 10−6 M 20-hydroxyecdysone (20HE) caused a threefold decrease in the 29 kDa MDK-binding protein. Presence of 3 × 10−6 M JH I prevented this loss. Allatectomy of molting 4th instar larvae after the critical period for JH for a larval molt resulted in the absence of the 29 kDa MDK-binding protein in epidermis isolated 25 hr later or from either day 1 5th instar larvae or day 1 pupae. Application of 5 μ of JH I or methoprene at the time of allatectomy and every 12 hr thereafter until dissection was necessary for the presence of this protein in day 1 5th instar larval epidermis. Application of 5 μg of JH I on the day of wandering and the next day caused the appearance of the 29 kDa MDK-binding protein in the epidermis of day 1 pupae formed by allatectomized larvae.
Integration of positive emotional experiences as part of a recreation program

Participants were children, aged 9–12, in a summer recreation program administered by a neighborhood settlement house. One group was given small group experiences to enhance self-acceptance and acceptance of others, while the other group participated in the usual recreation activities. Special experience participants demonstrated a significantly greater decrease on self-reported anxiety and impulsivity measures. There were no significant differences between the groups on measures on self-concept and ideal self, nor on social adjustment ratings made by the staff. Six months after the program ended, there were no differences between the groups on either the anxiety and impulsivity measures or the self-concept and ideal self measures. However, teacher's ratings at the follow-up favored the special experience group as regards the ability to get along well with others, exert self-control and assume responsibility for their work.
Peripheral arterial tonometry for risk stratification in men with coronary artery disease.

Background Coronary artery disease (CAD) risk is not fully revealed by traditional risk factors. Identification of a simple, noninvasive tool that allows for detection of high-risk CAD patients and can be applied in large populations and clinical settings would prove valuable. Hypothesis We sought to test the hypothesis that peripheral arterial tonometry (PAT) would be associated with residual risk in men with CAD. Methods In this study, finger PAT was used to measure pulse wave amplitude (PWA) during reactive hyperemia (RH) and taken as a measure of microvascular endothelial function in 42 men with stable CAD and well controlled low-density lipoprotein cholesterol (LDL-C) levels. Plasma levels of high-sensitivity C-reactive protein (hs-CRP) and lipoprotein-associated phospholipase A2 (Lp-PLA2) were measured and used to reclassify men into high-risk (elevated hs-CRP and Lp-PLA2), moderate-risk (either elevated hs-CRP or Lp-PLA2), or low-risk (low hs-CRP and Lp-PLA2) groups. Results PWA-RH was significantly lower in the high-risk group (1.3 ± 0.04) compared to the moderate-risk (1.6 ± 0.07, P < 0.05) and low-risk (2.0 ± 0.1, P < 0.05) groups. According to binary logistic regression, PWA-RH was a significant predictor of high-risk status among men with CAD (P < 0.05). Conclusion Measurement of peripheral microvascular endothelial function with PAT may be able to distinguish high-risk men from moderate- and low-risk men with stable CAD and well-controlled LDL-C levels and thus aid in residual risk stratification in this at risk cohort. Copyright © 2010 Wiley Periodicals, Inc.
Development of a Canadian large optical telescope

ABSTRACT This paper reviews Canadian involvement in the development of a 20 to 30-m large optical telescope. The history of Canadian Large Optical Telescope development is presented, from initial studies to replace the Canada France Hawaii Telescope (CFHT) on Mauna Kea, to the development of the Very Large Optical Telescope 20-m design, to the current partnership of Canada, the Association of Universities for Res earch in Astronomy (AURA), the California Institute of Technology, and the University of California in developing the Thirty Meter Telescope (TMT). Canadian technical studies are reviewed, including details of aerodynamic studies, enclosure and teles cope structural designs, optics, mirror coatings, adaptive optics and instrumentation, performance simu lations and integrated mode ling. The current status of technical developments in the TMT project is presented. Keywords: Large Optical Telescope, Canada, VLOT, TMT 1. INTRODUCTION Discussion of the next generation of op tical telescopes began worldwide in the mid 1990s. For Canada, the concept of a future optical telescope took shape in 1997 with the formation of the New Gene ration CFHT Committee. This group was asked to determine the type of ground-based facility that might succeed the current 3.6-m telescope in the 2010 decade, taking into account the planned array of new astronomical facilities. The report of this committee included a comprehensive assessment of planned poten tial facilities. Of the three op tions presented in its co nclusion, the preferred one was a telescope in the 25-m class
Structure of repaired sites in human DNA synthesized in the presence of inhibitors of DNA polymerases alpha and beta in human fibroblasts

Abstract Excision repair of ultraviolet damage in human fibroblasts was partially inhibited by drugs that block DNA polymerases α or β (cytosine arabinoside, aphidicolin and dideoxythymidine) causing a reduction in unscheduled synthesis and an accumulation of single-strand breaks. The strand breaks accumulated in the presence of aphidicolin could be resealed within 30 min after removal of the drug, but those accumulated by cytosine arabinoside took many hours. Digestion of repaired DNA with exonuclease III or S1 nuclease revealed that even the highest concentration of polymerase inhibitors, singly or in combination, that produced maximal accumulation of single-strand breaks only blocked 37–86% of repair sites. Use of single-strand break frequencies to measure the number of repair events can therefore be in error by as much as a factor of 3. The blocked patches with free 3′OH termini were, on average, 22% of normal length, corresponding to between 6 and 17 bases (assuming a normal patch of 25–75 bases in length). Patches that remained unsealed in vivo were also resistant to sealing by T4 ligase in vitro. The data are more consistent with a mechanism of repair in which long single-strand gaps are first made by excision enzymes and subsequently filled in by DNA polymerase α. Strand displacement or nick translation mechanisms seem unlikely.
Potassium canrenoate in the treatment of long-term digoxin-induced arrhythmias in conscious dogs

The effects of potassium canrenoate on arrhythmias induced by longterm progressive digoxin toxicity were studied in eight conscious beagle dogs. Sinus bradycardia and sinoatrial block, as well as atrioventricular (A-V) conduction disturbances, were consistently alleviated by administration of potassium canrenoate. Premature supraventricular (including junctional) and ventricular depolarizations as well as ventricular tachycardias were also suppressed. Although potassium canrenoate always terminated the digitalis-induced arrhythmias, it usually converted the rhythm to sinus arrhythmia rather than to normal sinus rhythm. Equimolar sodium canrenoate, but not potassium chloride, had similar reversal effects on arrhythmias induced by long-term digoxin intoxication. These data indicate that canrenoate, a diuretic agent with reported positive inotropic effects, may be useful in the treatment of digitalis-induced arrhythmias in man.
Casimir light: a glimpse.

Abstract Light emission produced by the reversible collapse of a cavity in a dielectric medium is given an initial, simplified treatment. The agreement between planar and spherical shapes indicates the volume nature of the effect.
Spatial factors in metacontrast

Different mask ring widths, intercontour distances, mask durations, and interstimulus intervals were varied in a parametric manner. Results show decreasing amounts of metacontrast with increases in intercontour distance, and no significant effects of mask width or mask duration. The results provide support for monotonic metacontrast functions with maximum metacontrast at the offset of the target.
Daytime variations of ozone eddy fluxes to maize

The vertical fluxes of ozone, momentum and heat in the atmospheric surface layer have been measured by eddy correlation above both mature and senescent maize canopies. Aerodynamic formulae are applied to find that the bulk canopy surface resistancerc to ozone uptake and destruction varies between 4.0 and 0.5 s cm−1 during the daytime. Apparently, surface properties tend to control the removal of ozone at the surface of the earth. For a lush canopy, the stomatal diffusion resistance is the most important property, while changes in surface temperature have little effect. Destruction at the soil and exterior plant surfaces appears to account for 20–50% of the total loss if leaf mesophyll resistances are assumed to be very small. Free water at leaf surfaces may at times inhibit ozone removal by both senescent and healthy plants.
Issues related to the practice of prescribing.

Prescribing a drug is intended to bring about a desired beneficial change in the health of an individual and has been practiced for centuries. The historical development, controls and regulations, and trends and issues in prescribing are provided to give nurses a strong foundation for practice. In almost all states, prescriptive authority has been expanded to include advanced practice nurses. An awareness of federal and state statutes and regulations can help nurses administer drugs in a safe, effective, and timely manner. JOGNN, 28, 513-519 1999.
The A and B loci of Nicotiana tabacum have non-equivalent effects on the mRNA levels of four alkaloid biosynthetic genes

The A and B loci of Nicotiana tabacum are the two major quantitative loci affecting nicotine levels. The A and B loci are thought to be regulatory genes because mutant alleles result in decreased nicotine accumulation and decreased enzyme levels of three nicotine biosynthetic activities. In this report, a combination of RNA gel blot and quantitative real time PCR analysis were performed to determine whether the steady state mRNA accumulation levels of four known multigene families involved in nicotine biosynthesis were also effected by the mutant a and b alleles. The absolute mRNA accumulation levels and relative fold-induction of each multigene family differed among the four multigene families. The homozygous mutant a genotype alone resulted in decreased mRNA accumulation of all four genes, whereas the single homozygous b genotype did not. However, the homozygous double mutant (aabb) showed lower mRNA accumulation levels than either the single homozygous mutant genotype alone, indicating that the mutant a and b gene products were acting synergistically to further decrease mRNA levels. These results demonstrate that the A and B loci are non-equivalent regulatory loci that decrease the steady state mRNA levels of at least four alkaloid biosynthetic genes.
Polarization dependence of Born effective charge and dielectric constant in KNbO3.

The Born effective charge ${\mathrm{Z}}^{\mathrm{*}}$ and dielectric tensor ${\mathrm{\ensuremath{\epsilon}}}_{\mathrm{\ensuremath{\infty}}}$ of ${\mathrm{KNbO}}_{3}$ are found to be very sensitive to the atomic geometry, changing by as much as 27% between the paraelectric cubic and ferroelectric tetragonal and rhombohedral phases. Subtracting the bare ionic contribution reveals changes of the dynamic component of ${\mathrm{Z}}^{\mathrm{*}}$ as large as 50%, for atomic displacements that are typically only a few percent of the lattice constant. ${\mathrm{Z}}^{\mathrm{*}}$, ${\mathrm{\ensuremath{\epsilon}}}_{\mathrm{\ensuremath{\infty}}}$, and all phonon frequencies at the Brillouin zone center were calculated using the ab initio linearized augmented plane-wave linear response method with respect to the reference cubic, experimental tetragonal, and theoretically determined rhombohedral ground-state structures. The ground-state rhombohedral structure of ${\mathrm{KNbO}}_{3}$ was determined by minimizing the forces on the relaxed atoms. In contrast to the cubic structure, all zone-center phonon modes of the rhombohedral structure are stable, and their frequencies are in good agreement with experiment. In the tetragonal phase, one of the soft zone-center modes in the cubic phase is stablized. In view of the small atomic displacements involved in the ferroelectric transitions, it is evident that not only the soft-mode frequencies but also the Born effective charge and dielectric constants are very sensitive to the atomic geometry. \textcopyright{} 1996 The American Physical Society.
The Role of Traditional Foods in Diabetes Prevention and Management among Native Americans

This article presents the historical and geopolitical context of the development of diabetes among Native people and the impact of dietary changes on Native American food culture. In the traditional Native American diet, farming and food were interwoven into a balanced lifestyle for maintaining life, celebrating and honoring culture, and fostering relationships in families and communities. Current trends focusing on families and communities, and strengthening and valuing tribal cultures may offer a blueprint for improving the health of Native people.
Ejection of glass rings during tightly focused femtosecond laser damage at a glass surface

We observe a discontinuity in the scaling between the size of damage and the pulse energy for femtosecond laser pulses tightly focused at a glass surface. This discontinuity corresponds to the threshold for formation and ejection of rings of material surrounding the focus center. The mechanism for the generation of these structures appears distinct from that of the central holes and is ascribed to subsurface absorption leading to thermal expansion and shock wave formation.
Optimization of peptide-based inhibitors of prostate-specific antigen (PSA) as targeted imaging agents for prostate cancer.

Prostate-Specific Antigen (PSA) is a serine protease biomarker that may play a role in prostate cancer development and progression. The inhibition of PSA’s enzymatic activity with small molecule inhibitors is an attractive and, as of yet, unexploited target. Previously, we reported a series of peptidyl aldehyde and boronic acid based inhibitors of PSA. In this study, the structural requirements in the P2 and P3 positions of peptide based PSA inhibitors are explored through the substitution of a series of natural and unnatural amino acids in these positions. This analysis demonstrated a preference for hydrophobic residues in the P2 position and amino acids with the potential to hydrogen bond in the P3 position. Using this information, a peptide boronic acid inhibitor with the sequence Cbz-Ser-Ser-Gln-Nle-(boro)-Leu was identified with a Ki for PSA of 25 nM. The attachment of a bulky metal chelating group to the amino terminal of this peptide did not adversely affect PSA inhibition. This result suggests that a platform of PSA-inhibitor chelates could be developed as SPECT or PET-based imaging agents for prostate cancer.
Tryptophan Metabolism in Bladder Cancer Patients from Copenhagen

Urinary excretion before and after a loading dose of tryptophan, plasma pyridoxal phosphate concentration and urinary excretion of 4-pyridoxic acid was studied in 44 male bladder cancer patients from Copenhagen. Six patients (14%) had abnormal tryptophan metabolism, decreased plasma pyridoxal phosphate concentration and in most cases low urinary excretion of 4-pyridoxic acid indicating decreased availability of vitamin B6 or decreased formation of pyridoxal phosphate from vitamin B6. It is concluded that abnormal tryptophan metabolism only plays a minor role for bladder cancer carcinogenesis in Copenhagen. It is, however, stressed that such studies do not rule out the possibility that the aromatic degradation products of tryptophan may be cocarcinogens or promotors as other studies have indicated.
Proton Radiation Therapy Offers Reduced Normal Lung and Bone Marrow Exposure for Patients Receiving Dose-Escalated Radiation Therapy for Unresectable Stage III Non-Small-Cell Lung Cancer: A Dosimetric Study

Abstract Introduction The purpose of this study was to determine the potential benefit of proton radiation therapy over photon radiation therapy in patients with unresectable stage III non-small-cell lung cancer. Materials and Methods Optimized 3-dimensional conformal photon (3DCRT), intensity-modulated radiation therapy (IMRT) and proton therapy (PT) plans were generated for 8 consecutive patients with unresectable stage III non–small-cell lung cancer using the same target goals and normal tissue constraints. The radiation exposure to non-targeted normal structures, including lung, bone marrow, esophagus, heart, and spinal cord, were compared. Photon doses are expressed in gray (Gy). Proton doses are expressed in cobalt gray equivalents (CGE). Results In all patients, 3DCRT, IMRT, and PT plans, achieved the dose goals for the target volumes. Compared with the 3DCRT plans, proton plans offered a median 29% reduction in normal lung V20 Gy (CGE), a median 33% reduction in mean lung dose (MLD), and a median 30% reduction in the volume of bone marrow receiving a dose of 10 Gy (CGE). Compared with the IMRT plans, the proton plans offered a median 26% reduction in normal lung V20 Gy (CGE), a median 31% reduction in MLD, and a median 27% reduction in the volume of bone marrow receiving a dose of 10 Gy (CGE). Conclusion By reducing the volumes of normal structures irradiated, protons can potentially improve the therapeutic index for patients with unresectable stage III non-small-cell lung cancer receiving combined radiation therapy and chemotherapy.
Zeno's Paradox of Immortality

Scientists who speculate on the future of human longevity have a broad range of views ranging from the promise of immortality, to radical life extension, to declines in life expectancy. Among those who contend that radical life extension is already here, or on the horizon, or immortality is forthcoming, elements of their reasoning appear surprisingly close, if not identical, to a famous mathematical paradox posed by the ancient Greek mathematician known as Zeno. Here we examine the underlying assumptions behind the views that much longer life expectancies are forthcoming or have already arrived, and place their line of reasoning within the context of a new Zeno paradox described here as The Paradox of Immortality.
Helping Professionals Understand Families.

Communication and collaboration between parents and professionals are vital. Pre- and inservice courses are one way of helping professionals develop communication and collaboration skills. A course at the University of New Hampshire attempts to provide this training. As a method of formative evaluation, pre-, post-, and follow-up questionnaires were distributed to students participating in the course during 1988, 1989, and 1990. Responses to the questionnaires indicated that attitudes of professionals and their interactions with parents changed. Greater empathy, increased respect, and significantly more parent collaboration and communication were reported in the follow-up questionnaires. Readings, interviews, and respite provision were some of the factors identified as influential in effecting increased positive interaction between parents and professionals.
Pilot study of a web-based antibiotic decision management guide.

Background Use of electronic medical information resources by health-care professionals is increasing. Portable handheld computers have facilitated access to medical knowledge at the point of patient care. Little is known about the impact of mobile medical information tools on physician learning or improvement in decision-making. Study design A 6-month prospective, randomized pilot study of 12 first-year trauma and critical care Fellows at the R Adams Cowley Shock Trauma Center was conducted from November 1, 2001 to May 31, 2002 at the University of Maryland. Six Fellows were randomized to use the Johns Hopkins Antibiotic Guide (JHABX) on the RIM Blackberry personal digital assistant (PDA) for 6 months of their clinical rotation. Six Fellows were randomized to the non-PDA−use arm. Three-month and 6-month examination raw scores on knowledge of infectious diseases management among Blackberry PDA users versus non-PDA users were obtained. Measurement of antibiotic decision accuracy by diagnosis at 3 and 6 months among Fellows randomized to use the JHABX on the RIM Blackberry PDA was also evaluated. Results PDA group demonstrated a considerable improvement in test scores over the 3-month time interval, compared with their baseline score (40.8 ± 2.3 versus 34.3 ± 4.6, p Conclusions Web-based handheld technology is highly effective for supplying information to support infectious disease clinical practice. In a hospital intensive care setting, results of this study demonstrate that resident physician knowledge and antibiotic decision selection accuracy improved among Fellows using the JHABX. Reasons for this difference can be multifold and not thoroughly evaluated from this small pilot study. Future studies on the impact of point-of-care technology on patient outcomes are warranted.
An in vitro three-dimensional coculture model of cerebral microvascular angiogenesis and differentiation

The microvasculature of the developing brain is plastic and responds differently to the many insults associated with preterm birth. We developed three-dimensional in vitro culture models for the study of the responses of the developing cerebral micro-vasculature. Beagle brain microvascular endothelial cells (BBMEC) were isolated by differential centrifugation from newborn beagle pups on postnatal Day 1 and placed in three-dimensional culture dispersed in a collagen gel. Alternatively, BBMEC were placed in a three-dimensional coculture with neonatal rat forebrain astrocytes. Cultures were analyzed for extracellular matrix components at 1 and 6 d, and total RNA was extracted for Northern analyses. Urokinase plasminogen activator activity was assayed in both mono- and cocultures of the two cell types. Studies of three-dimensional BBMEC/astrocyte cocultures demonstrated progressive tube formation with only low levels of endothelial proliferation. By 6 d in three-dimensional coculture, the BBMEC formed capillarylike tubes with a wrapping of glial processes, and basement membrane protein synthesis was noted. Urokinase plasminogen zymography suggested intercellular signaling by the two cell types. These data suggest that the three-dimensional beagle brain germinal matrix microvascular endothelial cell/neonatal rat astrocyte coculture provides a good model for the investigation of microvascular responses in the developing brain.
A Meta-analytic Investigation of Neurocognitive Deficits in Bipolar Illness: Profile and Effects of Clinical State

A meta-analysis of neuropsychological studies of patients with bipolar disorder comprised of 42 studies of 1,197 patients in euthymia, 13 studies consisting of 314 patients in a manic/mixed phase of illness, and 5 studies of 96 patients in a depressed state. Cohen d values were calculated for each study as the mean difference between patient and control group score on each neuropsychological measure, expressed in pooled SD units. For euthymia, results revealed impairment across all neuropsychological domains, with d values in the moderate-to-large range (d = .5 - .8) for the vast majority of measures. There was evidence of large effect-size impairment on measures of verbal learning (d = .81), and delayed verbal and nonverbal memory (d = .80 - .92), while effect-size impairment on measures of visuospatial function was small-to-moderate (d <or= .55). Patients tested during a manic/mixed or depressed phase of illness showed exaggerated impairment on measures of verbal learning, whereas patients tested during a depressed phase showed greater decrement on measures of phonemic fluency. These results suggest that bipolar illness during euthymia is characterized by generalized moderate level of neuropsychological impairment with particular marked impairment in verbal learning and memory. These results also show that a subset of these deficits moderately worsen during acute disease states.
Seasonal changes in avian song control circuits do not cause seasonal changes in song discrimination in song sparrows.

In seasonally breeding songbirds, brain nuclei of the song control system that act in song perception change in size between seasons. It has been hypothesized that seasonal regression of song nuclei may impair song discrimination. We tested this hypothesis in song sparrows (Melospiza melodia), a species in which males share song types with neighbors and must dis- criminate between similar songs in territorial interac- tions. We predicted that song sparrows with regressed song systems would have greater difficulty in discrimi- nating between similar songs. Sparrows were housed either on short days (SD) and had regressed song cir- cuits, or were exposed to long days and implanted with testosterone (LDT) to induce full growth of the song circuits. We conducted two experiments using a GO/ NO-GO operant conditioning paradigm to measure song discrimination ability of each group. Birds learned four (experiment 1) or three (experiment 2) pairs of song types sequentially, with each pair more similar in the number of shared song elements and thus more difficult to discriminate. Circulating T levels differed between the SD and LDT groups. The telencephalic song nuclei HVc, RA, and area X were larger in the LDT birds. The two groups of sparrows did not differ, however, in their ability to learn to discriminate between shared song types, regardless of the songs' similarity. These results suggest that seasonal changes in the song control system do not affect birds' ability to make difficult song
Bacterial contamination of saline nasal spray/drop solution in patients with respiratory tract infection

This study evaluated the potential for bacterial contamination of saline nasal spray/drop solution after 3 days of clinical use in patients. Twenty patients with upper respiratory infection used the saline as a spray, and 20 patients used the solution as drops. Bacterial growth was present in 18 (90%) solution containers of the spray group and in 3 (15%) solution containers of the drops group (P < .005). Twenty isolates were recovered from the spray group and 3 from the drops group. The pre- dominate isolates included Staphylococcus aureus, Staphylococcus epidermidis, alpha Streptococcus species, Pseudomonas aeruginosa, Escherichia coli, and Proteus spp. This study demonstrates the contamination of nasal saline-dispensing solution used as a spray with micro-organisms that are part of the normal skin and nasal flora and gram-negative organisms of poten- tial enteric origin. These data support the use of nasal saline-dispensing solution as drops, rather than as spray. They also illustrate the risk for crossinfection if a nasal solution is used by more than 1 patient. (Am J Infect Control 2002;30:246-7.)
Is Mentoring Enough? An Examination of the Mentoring Relationship in the Pilot Two-Year Kentucky Teacher Internship Program

This article examines a pilot program's mentoring component involving first-year interns and veteran teachers in relation to new teachers' needs and effects regarding support and professional development. Mentoring along with delayed work requirements and evaluation increased interns' adjustment to teaching. However, emotional and technical support through mentoring proved inadequate in meeting needs. Interns wanted structured professional development including information sharing, peer networking, and evidence of professional growth. The article increases our understanding of mentoring and has policy implications to promote effective induction for new teachers.
Bulky tris(mercaptoimidazolyl)borates: synthesis and molecular structures of the Group 12 metal complexes [TmtBu]MBr (M = Zn, Cd, Hg)

An improved preparation of the bulky tris(mercaptoimidazolyl)borate ligand [TmtBu]− is reported together with convenient high yield syntheses of the Group 12 metal derivatives [TmtBu]MBr (M = Zn, Cd, Hg). The molecular structures of the three new complexes have been determined by single-crystal X-ray diffraction and together constitute the first complete triad of TmR compounds in the periodic table to be structurally characterized. The isostructural complexes display in the solid state distorted tetrahedral structures, with the heavier members of the group exhibiting larger Br–M–S and smaller S–M–S angles.
The Edwards–Wilkinson model revisited: large-scale simulations of dynamic scaling in 2+1 dimensions

Abstract Using extensive simulations of surface growth in the 2+1 dimensional atomistic model of Edwards and Wilkinson (EW), we have calculated both interfacial width and the structure factor, to extract the dynamic exponent z. In contrast to theoretical expectations, finite-size scaling of the data for both surface properties is achieved using z∼1.63, instead of the predicted value of 2.0. A restricted variant of the EW model gives z∼2.0. Clarifying these non-trivial differences in dynamical correlations, now represents an intriguing theoretical challenge.
Wavelet-based signal processing and optics

Recent advances in mathematical theory related to the representation of signals and images by some limited-extent-wave functions have generated substantial interest in applications of waveforms that are localized in both time (space) and frequency (spatial frequency) domains to signal and image processing, pattern recognition, data compression, and neural networks. As a particularly useful model, the so-called wavelet transforms provide a variety of multiresolution signal (image) time-frequency or space-frequency decomposition tools. Digital parallel implementations of the wavelet transforms are computationally intensive both because of the nature of the coordinate dilation and erosion of these transforms and because of the large quantity of convolution/correlation operations accompanied. This paper is intended to outline some of the most useful properties of the wavelet transforms, their similarities, and differences to other known joint representations. The links between the wavelet transforms and optics also are discussed.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Recent Developments in the Surgical Management of Benign Prostatic Hyperplasia

A new era in the surgical management of benign prostatic hyperplasia (BPH) has emerged in the past decade. A variety of less invasive treatment modalities have been introduced and well-established surgical treatments are being reassessed. Although progress has been made in the management of BPH, the substantial economic burden to the healthcare system caused by BPH emphasizes the importance of cost-effective treatment. Open prostatectomy is the most efficient BPH treatment for relieving symptoms and improving uroflow, but it is also the most invasive and morbid. Transurethral resection of the prostate (TURP) is still the "gold standard" for treatment of BPH, but open prostatectomy has been reported to have a lower perioperative mortality than TURP, and low retreatment rates reduce the long-term cost. The morbidity associated with TURP, such as impotence or urinary incontinence, has been reduced in recent years while new features, such as performing TURP under local anesthesia and bipolar electrosurgical techniques, have been introduced. Transurethral electrovaporization of the prostate (TVP) is a recent modification of TURP that has rapidly gained popularity. TVP greatly reduces TURP syndrome, provides good hemostasis, and may reduce catheterization and hospitalization times. Transurethral incision of the prostate (TUIP) is another safe and inexpensive procedure that is well-documented and comparable to TURP in long-term efficacy. TUIP is an underused procedure with which the newer, less invasive treatments should be compared. Whereas the well-established surgical treatments primarily relieve obstruction by tissue ablation, some of the newer treatment modalities may ameliorate lower urinary tract symptoms (LUTS) with minimal urodynamic change. In some of the newer nonresection treatments, no major significant postoperative reduction in prostate volume can be demonstrated. Laser treatments are based on a broad variety of techniques, generators, and fibers, of which most have initially demonstrated promising results. Well-known techniques include visually laser-assisted prostatectomy (VLAP) and interstitial laser coagulation (ILC). The laser techniques are generally not as effective as TURP, but are safe under local anesthesia on an outpatient basis with low complication rates. Transurethral microwave thermotherapy of the prostate (TUMT) and radiofrequency transurethral needle ablation (TUNA) are minimally invasive, safe new therapies. There is some evidence that the procedures create long-term, alpha-adrenoceptor-like blockade. Complications, except for transient catheterization in up to 40% of patients, may be practically nonexistent. The cost is difficult to estimate and the long-term outcome is still to be assessed. If the newer, less invasive treatment modalities provide stable long-term results and competitive costs, they will be tempting alternatives to prostate resections and may also challenge medical therapy.
Pulses of tunable size near a subcritical bifurcation

We show that a nonlinear gradient term can be used to tune the width of pulse-like solutions to a generalized quintic Ginzburg-Landau equation. We investigate the dynamics of these solutions and show that weakly turbulent patches can persist for long times. Analogies with turbulent spots in plane Couette flows are discussed.
Hyperosmotic activation of transmitter release from presynaptic terminals onto retinal ganglion cells

A method for evoking neurotransmitter release without light stimulation has been developed and applied to a retinal slice preparation of the tiger salamander (Ambystoma Tigrum). This method utilizes a micropipette containing hyperosmotic levels of sucrose in Ringer, positioned within the inner plexiform layer (IPL) under visual control. Intermittent pressure (between 0.1 and 2 bars) applied to the pipette evoked release of neurotransmitters which were evaluated with whole-cell recording (WCR) techniques applied to cells in the ganglion cell layer. Pharmacological studies were used to characterize the properties of the hyperosmotic sucrose-evoked response (HSER) and in some cases, we compared the HSER with synaptic currents evoked by light stimulation. The HSER typically consisted of both inhibitory and excitatory components with a reversal potential in between that for chloride (approximately −60 mV) and non-specific cation channels (approximately 0 mV). Relatively pure inhibition or excitation could be revealed through pharmacological techniques by blocking the inhibition with picrotoxin/strychnine or by blocking the glutamatergic neurotransmission with D-AP7 (D-2-amino-7-phosphonoheptanoate) and NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo (F) quinoxaline). A comparison of lightevoked responses (LER) and the HSER suggested that they activate the same pool of releasable neurotransmitter.
Inventing one's "voice": The interplay of convention and self-expression in ASL narrative

Drawing on the work of Jean-Francois Lyotard and Mikhail Bakhtin, this study analyzes personal narratives created and performed in American Sign Language (ASL) by three Deaf college students. These narratives can be viewed as "boundary phenomena" in that they reflect themes common to the Deaf oral tradition, yet were deliberately poetically created, extensively rehearsed and publicly performed, based on fact, and created with a specific rhetorical purpose. The texts are examined for literary features and themes, as well as for the key elements of performance and social-cultural context. Discussion centers on the ways in which students' individual styles emerged from exposure to the thematic and stylistic techniques of professional Deaf artists. (American Sign Language, personal narrative, narrative pragmatics, speech genres, intertextuality)*