cssi/SciSciGPT-SciSciNet huggingface dataset:
CONTEXT: a CONstrainT EXplanation Tool

Abstract Encapsulation is an important concept within the object-oriented paradigm. A problem with encapsulation in an object-oriented database, however, is that important semantic information may be hidden within database operations, stripping the database system of information needed for intelligent database activities such as query processing or the ability to reason about objects. This paper describes the functionality of a constraint explanation tool known as CONTEXT. CONTEXT was developed to be used within an environment where database semantics are expressed in a declarative manner, rather than encapsulating constraints within database operations. The database system is therefore responsible for managing information about constraints and checking constraints at execution time. CONTEXT provides a way of sharing information about constraints with the designer at the time database operations are formed, explaining how constraints affect operations and assisting the designer in specifying propagation actions for responding to constraint violations. As a result, operations on objects encapsulate information about how to respond to constraints (in the form of rules), rather than encapsulating information about constraints themselves. The internal processing required to support the explanation of constraints and the identification of alternative propagation actions for transforming constraints to rules is described.
Evaluation of the implementation of the H1N1 pandemic influenza vaccine in local health departments (LHDs) in North Carolina.

Abstract Introduction Effective conduct of vaccination campaigns by public health authorities can reduce morbidity and mortality associated with influenza. The emergence of the pandemic H1N1 influenza in April 2009 resulted in an unprecedented vaccination campaign in the US during the 2009–2010 influenza season. The variety of methods local health departments (LHDs) utilized to cope with a mismatch between public demand and supply and ever-changing guidelines have gone unexamined thus far. The purpose of this research is to identify and share lessons learned related to H1N1 influenza vaccination activities at LHDs. Methods In April 2010, a comprehensive survey was developed to evaluate 2009-10 LHD H1N1 vaccination practices and document lessons learned. A stratified random sample was selected from NC's 85 LHDs. Interviews were conducted with key personnel involved in LHD vaccination campaigns. Results were analyzed to identify quantitative trends and qualitative themes. Results Twenty-five of 26 LHDs (96% response rate) participated in our survey. Each LHD utilized a different approach to address the challenges they faced during their H1N1 vaccination campaign. Variation between LHDs was found in terms of the types of vaccine-dispensing methods implemented and in the selection of outside organizations LHDs partnered with to assist with vaccinations. Conclusion Having a Continuity of Operations Plan (COOP) and pandemic influenza plan, hiring temporary staff, building on existing community partnerships, implementing a variety of vaccination strategies and using a variety of sites are strategies that will help LHDs deal more effectively with challenges posed by future pandemics.
Neutron transmutation doping of a-Si:H

Abstract Neutron transmutation doping of a-Si:H has been reexamined, and found unsuitable for practical application. Changes under anneal near the deposition temperature of both NTD and gas-phase doped films raise basic questions about the concept of doping efficiency.
Effect of dietary fatty acid manipulation upon the inducibility of hepatic tyrosine aminotransferase by cortisol

Summary The present study clearly shows that, by feeding rats a semi-synthetic diet of known composition enriched with fatty acids of varying degrees of saturation, the inducibility of the hepatic cytosolic enzyme tyrosine aminotransferase by cortisol is markedly altered. In animals fed a diet enriched with saturated fatty acids (as coconut oil), cortisol, injected intraperitoneally, showed a much lower ability to induce tyrosine amino-transferase synthesis than in animals fed a diet enriched with polyunsaturated fatty acids (as safflower oil). Enzyme synthesis in response to cortisol injection in animals fed a diet rich in corn oil showed an intermediate response relative to that in the animals fed either coconut oil or safflower oil. Potential mechanisms for this phenomenon are discussed.
Durability of new squamous epithelium after endoscopic reversal of Barrett's esophagus.

Abstract Background: Endoscopic reversal of Barrett’s esophagus with multipolar electrocoagulation and high-dose omeprazole has been previously described but long-term results are not available. The aim of this study was to follow patients after endoscopic reversal and to perform a detailed analysis of the “new” squamous mucosa. Methods: After reversal, patients with Barrett’s esophagus were maintained on high-dose omeprazole and underwent interval endoscopy, and large biopsies were obtained of the former Barrett’s epithelium. Results: Nine of 11 patients were men; the mean age was 62 years. The mean length of Barrett’s mucosa was 4.4 cm; the mean dose of omeprazole used was 49 mg/day. All patients had an initial complete response to treatment—no evidence of Barrett’s endoscopically and histologically. Three patients had intestinal metaplasia underlying the new squamous mucosa in the latest follow-up biopsies. In these 3 patients, only 0.4%, 2%, and 8% of the total biopsy area had intestinal metaplasia. All but 4 patients had underlying intestinal metaplasia at variable times during the study period. Patients have been followed for a mean of 36 months (range 19 to 53 months). Conclusions: New squamous mucosa is durable and resembles normal squamous tissue. Underlying glands of intestinal metaplasia are intermittently found. Because the significance of this residual intestinal metaplasia is unclear, surveillance endoscopy with biopsies of the treated segment is recommended even after reversal therapy. (Gastrointest Endosc 1999;50:159-64.)
Dynamic Range Studies Of The RCA Streak Tube In The LLL Streak Camera

As indicated by tests on several cameras, the dynamic range of the Lawrence Livermore Laboratory streak-camera system appears to be about two orders of magnitude greater than those reported for other systems for 10- to 200-ps pulses. The lack of a fine mesh grid in the RCA streak tube used in these cameras probably contributes to a lower system dynamic noise and therefore raises the dynamic range. A developmental tube with a mesh grid was tested and supports this conjecture. Order-of-magnitude variations in input slit width do not affect the spot size on the phosphor or the dynamic range of the RCA tube.
Temperature-Dependent Histotypic Changes in Walker Carcinosarcoma in the Chorioallantois

Solid tumors grew in the chorioallantois of chick embryos after the topical inoculation of ascites tumor cells. The microscopic character of the growth varied depending on the temperature of incubation. At 32.5°C a sarcomatous appearance was prominent; at 37.5°C carcinomatous structure in several alveolar patterns predominated; at 42.5°C growth was that of a "giant cell" carcinoma.
ROLE OF VIRUL SPECIFIC Ige IN THE RELEASE OF LEUKOTRIENE C4 (LTC4) IN NASOPHARYNGEAL SECRETIONS (NPS) OF INPANTS WITH RESPIRATORY SUNCYTIAL VIRUS (RSV) INFECTION

Samples of NPS from groups of infants with bronchiolitis or upper respiratory illness alone during infection with RSV were analyzed for LTC4 content using a reverse-phase high-pressure liquid chromatography (HPLC) assay and confirmed by radioimmunoassay. Titers of RSV-specific IgE in NPS specimens were determined using an ELISA assay. LTC4 was present in 67% of samples obtained in the first week after the onset of illness and was detectable in progressively lower concentrations in samples obtained up to 27 days after the onset of illness, but not beyond. LTC4 was detectable in samples of NPS obtained in the acute phase of illness from 73% of infants with bronchiolitis due to RSV, and in about 30% of samples of NPS obtained during the same interval from infants with upper respiratory illness alone, significantly, however, quantities of LTC4 measured in NPS could be directly correlated with the magnitude of the peak RSV-IgE response in secretions (r=0.557, p<0.02). LTC4 was not detected in NPS specimens from any of the patients who did not develop an RSV-IgE response. These studies lend support to previous investigations suggesting that severe bronchiolitis due to RSV results from IgE-mediated hypersensitivity reactions to viral antigens, with release of chemical mediators of airway obstruction. Their implications should be considered in new approaches to therapy for RSV bronchiolitis.
On a stability criterion for continuous slow adaptation

Abstract A self-contained proof is given of a stability criterion for slow adaptation. The proof is based on a novel open-loop representation of the parameter adjustment feedback.
Instantaneous pressure gradient: A simultaneous doppler and dual catheter correlative study

To more precisely measure the beat to beat and instantaneous pressure gradients across outflow stenotic lesions, simultaneous Doppler and dual catheter pressure gradient measurements were performed in 95 patients (mean age 42 years, range 1.5 to 85). There were 38 right ventricular and 62 left ventricular outflow obstructive lesions. Forty-nine patients also had a nonsimultaneous Doppler study performed within 7 days before catheterization. The simultaneous pressure waveforms and Doppler spectral velocity profiles were digitized at 10 ms intervals deriving maximal, mean and instantaneous gradients (mm Hg). For simultaneous maximal Doppler and catheter gradient measurements, the correlation coefficient (r) was 0.95 (SEE = 10mm Hg), for Doppler and catheter mean gradients it was 0.94 (SEE = 8 mm Hg) and for maximal Doppler and peak to peak catheter gradients it was 0.92 (SEE = 13 mm Hg). The correlation of maximal and mean Doppler gradients with the respective catheter gradients was similarly high when the right and left ventricular outflow lesions were analyzed separately. However, the maximal Doppler gradient was significantly higiter than the peak to peak catheter gradient. This was more evident with left ventricular outflow stenotic lesions. The correlation of the outpatient maximal Doppler and catheter gradients (r = 0.80, SEE = 17 mm Hg) was significantly lower than the simultaneous correlation (r = 0.96, SEE =10 mm Hg) in the 49 patients with two Doppler studies. Continuous wave Doppler echocardiography accurately measures the instantaneous pressure gradient across both left and right ventricular outflow obstructive lesions. The maximal Doppler gradient should not be equated with the peak to peak catheter gradient. As Doppler echocardiography measures instantaneous pressure gradients, it should not be directly compared with nonsimultaneous events.
Turning primary care providers' attention to child behavior: A review of the literature

Twenty-five years ago, writers first drew the nation's attention to the "new morbidities"--problems that were biosocial or developmental in nature and were induced or complicated by social or environmental factors. The American Academy of Pediatrics responded by urging primary care providers to spend more time counseling parents on behavioral issues. Recent violent episodes in schools have renewed concern and prompted child health advocates to ask how well primary care providers are doing in attending to problematic childhood behavior. A review of the literature was conducted to examine the role the primary care provider plays in attending to childhood behavior.
Translational imaging endpoints to predict treatment response to novel targeted anticancer agents

Response Evaluation Criteria in Solid Tumors (RECIST) and World Health Organization (WHO) Criteria have been traditionally used for the evaluation of therapeutic response to chemotherapeutic treatment regimens. They determine anatomic criteria for patients response to anti-cancer therapy based on morphological measurements of each target lesion. While this assessment is justified for cytotoxic (chemotherapeutic) drugs, it is now recognized that morphological imaging protocols are poorly suited to the evaluation of the efficacy of novel signal transduction inhibitors (STIs) which exhibit cytostatic rather than cytotoxic properties. New imaging technologies are now designed to evaluate, in a functional manner, modifications in tumor metabolic activity, cellularity, and vascularization before a reduction in tumor volume can be detected. Introduction of physiological imaging end-points, derived from dynamic contrast-enhanced (DCE) imaging protocols--including magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US)--allow for early assessment of disruption in tumor perfusion and permeability for targeted anti-angiogenic agents. Diffusion-weighted MRI (DWI) provides another physiological imaging end-point since tumor necrosis and cellularity are seen early in response to anti-angiogenic treatment. Changes in glucose and phospholipid turnover, based on metabolic MRI and positron emission tomography (PET), provide reliable markers for therapeutic response to novel receptor-targeting agents. Finally, novel molecular imaging techniques of protein and gene expression have been developed in animal models followed by a successful human application for gene therapy-based protocols.
Estimation of invasive pneumococcal disease dynamics parameters and the impact of conjugate vaccination in Australia

Pneumococcal diseases, or infections from the etiological agent Streptococcus pneumoniae, have long been a major cause of morbidity and mortality worldwide. Recent advances in the development of vaccines for these infections have raised questions concerning their widespread and/or long-term use. In this work, we use surveillance data collected by the Australian National Notifiable Diseases Surveillance system to estimate parameters in a mathemat- ical model of pneumococcal infection dynamics in a population with partial vaccination. The parameters obtained are of particular interest as they are not typically available in reported literature or measurable. The calibrated model is then used to assess the impact of the recent federally funded program that provides pneumococcal vaccines to large risk groups. The results presented here suggest the state of these infections may be changing in response to the programs, and warrants close quantitative monitoring.
Role of ephrin B2 in human retinal endothelial cell proliferation and migration

This study was designed to determine the presence of Eph B4 or ephrin B2 in human retinal endothelial cells (REC) and their signal transduction. Human retinal endothelial cells were stimulated with an Eph B4/Fc chimera and probed for phosphorylation of phosphatidylinositol-3-kinase (PI3K), Src, and mitogen-activated protein kinase (MAPK) pathways. Proliferation and migration were investigated after Eph B4/Fc stimulation in the presence of various pathway inhibitors. Human retinal endothelial cells express ephrin B2, with little expression of Eph B4. Treatment with EphB4/Fc chimera resulted in activation of PI3K, Src, and MAPK pathways. Eph B4-stimulated endothelial cell proliferation was mediated via PI3K, nitric oxide synthase, and extracellular signal-regulated kinase 1/2 (ERK1/2). Blockade of Src-PI3K pathways produced significant attenuation of Eph B4/Fc-stimulated migration. These results demonstrate for the first time that ephrin B2 is present in human retinal endothelial cells. Additionally, it appears that vascular growth may be modulated in the retina through activation of the PI3K pathway and its downstream components.
Ligand-regulated Internalization, Trafficking, and Down-regulation of Guanylyl Cyclase/Atrial Natriuretic Peptide Receptor-A in Human Embryonic Kidney 293 Cells

Abstract We examined the kinetics of internalization, trafficking, and down-regulation of recombinant guanylyl cyclase/natriuretic peptide receptor-A (NPRA) utilizing stably transfected 293 cells expressing a very high density of receptors. After atrial natriuretic peptide (ANP) binding to NPRA, ligand-receptor complexes are internalized, processed intracellularly, and sequestered into subcellular compartments, which provided an approach to examining directly the dynamics of metabolic turnover of NPRA in intact cells. The translocation of ligand-receptor complexes from cell surface to intracellular compartments seems to be linked to ANP-dependent down-regulation of NPRA. Using tryptic proteolysis of cell surface receptors, it was found that ∼40–50% of internalized ligand-receptor complexes recycled back to the plasma membrane with an apparent t = 8 min. The recycling of NPRA was blocked by the lysosomotropic agent chloroquine, the energy depleter dinitrophenol, and also by low temperature, suggesting that recycling of the receptor is an energy- and temperature-dependent process. Data suggest that ∼70–80% of internalized 125I-ANP is processed through a lysosomal degradative pathway; however, 20–25% of internalized ligand is released intact into the cell exterior through an alternative mechanism involving an chloroquine-insensitive pathway. It is implied that internalization and processing of bound ANP-NPRA complexes may play an important role in mediating the biological action of hormone and the receptor protein. In retrospect, this could occur at the level of receptor regulation or through the initiation of ANP mediated signals. It is envisioned that the endocytotic pathway of ligand-receptor complexes of ANP-NPRA would lead to termination and/or diminished responsiveness of ANP in target cells.
RNA processing: Pocket guides to ribosomal RNA

Abstract The functional role of a recently identified class of small nucleolar (sno)RNAs has been elucidated: the ‘box H/ACA' snoRNAs act as guide RNAs, specifying the position of evolutionarily conserved pseudouridines in ribosomal (r)RNA via an rRNA–snoRNA base-pairing interaction that forms a ‘pseudouridine pocket'.
Temperature-Aware Scheduling for Embedded Heterogeneous MPSoCs with Special Purpose IP Cores

Many embedded heterogeneous MPSoCs integrate general purpose cores along with special purpose cores. The power states of these cores are usually controlled by an internal hardware controller rather than the central operating system. In this paper, we propose a thermal management technique which reduces the performance penalty of central thermal management by considering these special purpose cores and the performance requirements of the tasks running on them. Our experimental results show that for the workloads with high priority special purpose tasks, our technique can reduce the occurence of thermal violations by at least 3X while improving the weighted execution time by up to 24\%.
Talin regulates moesin-NHE-1 recruitment to invadopodia and promotes mammary tumor metastasis.

Invadopodia are actin-rich protrusions that degrade the extracellular matrix and are required for stromal invasion, intravasation, and metastasis. The role of the focal adhesion protein talin in regulating these structures is not known. Here, we demonstrate that talin is required for invadopodial matrix degradation and three-dimensional extracellular matrix invasion in metastatic breast cancer cells. The sodium/hydrogen exchanger 1 (NHE-1) is linked to the cytoskeleton by ezrin/radixin/moesin family proteins and is known to regulate invadopodium-mediated matrix degradation. We show that the talin C terminus binds directly to the moesin band 4.1 ERM (FERM) domain to recruit a moesin–NHE-1 complex to invadopodia. Silencing talin resulted in a decrease in cytosolic pH at invadopodia and blocked cofilin-dependent actin polymerization, leading to impaired invadopodium stability and matrix degradation. Furthermore, talin is required for mammary tumor cell motility, intravasation, and spontaneous lung metastasis in vivo. Thus, our findings provide a novel understanding of how intracellular pH is regulated and a molecular mechanism by which talin enhances tumor cell invasion and metastasis.
Oral versus Written Recollections of Prose.

After reading prose passages, undergraduate students retrieved and reported information in either the oral mode or written mode of production. Current information processing models indicate that superordinate concepts are recalled better than subordinate ideas from a text. Thus, dependent variables were number of superordinate concepts recalled, number of subordinate ideas recalled, number of readergenerated elaborations, and time taken to respond in each mode. Recalls were scored against an outline, for presence or absence of superordinate, subordinate, and reader-generated ideas contained in the passages. Total number of superordinate concepts, subordinate ideas, or reader-generated elaborations yielded no differences across modes of reporting. However, initial or ending position of information in the original text produced significantly different results when subjects recalled in the oral mode versus the written mode." For end position topics reported in the oral mode, when one level of concept was recalled without the other, it was always the subordinate concept that was recalled alone. These results have valuable implications for generative learning. According to contemporary language theorists (Adams & Collins, 1979; Anderson, 1984; Goodman, 1967), a spoken or written text does not in itself carry meaning. Rather, a text only provides directions for a listener or reader about how meaning should be constructed from one's own background of knowledge. How the reader uses a text to construct meaning in memory is a question that drives significant research on reading comprehension. In particular, one question was addressed in the present research: Does the expressed memory of a text differ if it is rendered orally rather than in writing? Because of different task demands on work
The epidemiology of college alcohol and gambling policies

This article reports the first national assessment of patterns of drinking and gambling-related rulemaking on college campuses (e.g., punitive versus recovery oriented). Analyses relating school policies to known school rates of drinking or gambling identified potentially influential policies. These results can inform and encourage the development of guidelines, or "best practices," upon which schools can base future policy. The college policy information was collected from handbooks, Web sites and supplemental materials of 119 scientifically selected colleges included in the fourth (2001) Harvard School of Public Health College Alcohol Study (CAS). A coding instrument of 40 items measured the scope and focus of school alcohol and gambling policies. This instrument included items to measure the presence of specific policies and establish whether the policies were punitive or rehabilitative. A total of 11 coders followed a process of information extraction, coding and arbitration used successfully in other published studies to codify policy information. Although all schools had a student alcohol use policy, only 26 schools (22%) had a gambling policy. Punitive and restrictive alcohol policies were most prevalent; recovery-oriented policies were present at fewer than 30% of schools. Certain alcohol and gambling policies had significant relationships with student binge drinking rates. The relative lack of college recovery-oriented policies suggests that schools might be overlooking the value of rehabilitative measures in reducing addictive behaviors among students. Since there are few college gambling-related policies, schools might be missing an opportunity to inform students about the dangers of excessive gambling.
Understanding the role of facial asymmetry in human face identification

Face recognition has important applications in forensics (criminal identification) and security (biometric authentication). The problem of face recognition has been extensively studied in the computer vision community, from a variety of perspectives. A relatively new development is the use of facial asymmetry in face recognition, and we present here the results of a statistical investigation of this biometric. We first show how facial asymmetry information can be used to perform three different face recognition tasks--human identification (in the presence of expression variations), classification of faces by expression, and classification of individuals according to sex. Initially, we use a simple classification method, and conduct a feature analysis which shows the particular facial regions that play the dominant role in achieving these three entirely different classification goals. We then pursue human identification under expression changes in greater depth, since this is the most important task from a practical point of view. Two different ways of improving the performance of the simple classifier are then discussed: (i) feature combinations and (ii) the use of resampling techniques (bagging and random subspaces). With these modifications, we succeed in obtaining near perfect classification results on a database of 55 individuals, a statistically significant improvement over the initial results as seen by hypothesis tests of proportions.
Novel local evanescent field detection waveguide multianalyte biosensor

A novel waveguide sensor capable of sensing multiple analytes directly and in real time with label-free, local detection has been investigated. Numerical simulations agree with analytical calculations of the sensor sensitivity. The waveguide parameters including detector to core distance, adlayer length, and surface roughness have been extensively analyzed. Initial experimental realization efforts are summarized.
Replication of ocular isolates of human adenovirus is serotype-dependent in rabbit corneal organ culture.

The goal of the present in vitro study was to determine the ability of unadapted human adenoviral ocular isolates to replicate in the rabbit cornea. Rabbit corneas grown in organ culture (24 well plate) were inoculated topically with 50 ul (5 ul 105 pfu) of different ocular adenoviral serotypes (ATCC and clinical isolates). Control wells (no cornea present) were inoculated in a similar fashion. Viral replication was determined by serial aliquots titrated on A549 cells. We demonstrated sustained viral replication over time of all isolates (100%) of Adl, 2, 5, 6, 8, 9, 11 and 37 tested. No isolates (0%) of Ad3, 7A, 19, and 4 demonstrated replication in our model. Peak titers varied among successful serotypes from 102 pfu/ml (Adll) to 105 PFU/ml (Ad5), and among different isolates of a given serotype. We conclude that the ability of unadapted human Ad serotypes to replicate in rabbit corneas was serotype-dependent, and that subgroup C (Adl, 2, 5, and 6) appeared to be the most successful subgroup.
Alginate encapsulation and hepatic differentiation of embryonic stem cells

The emergence of cell based clinical technologies has been limited by the need for large cell masses (>10/sup 11/ cells). Embryonic stem cells are a promising solution to this cell source limitation because they are highly proliferative, renewable and pluripotent. Although many investigators have described techniques to effectively differentiate stem cells into a variety of mature cell lineages, these fall short in a number of ways including: 1) low yields of fully differentiated cells, 2) absence of large scale processing considerations and 3) ineffective downstream enrichment. Thus, a tissue culture microenvironment is required that may be modified to increase regulation of embryonic stem cell differentiation, and scaled to increase differentiated cell yield. Microencapsulation provides a vehicle for the discrete control of key cell culture parameters such as cell seeding density, rigidity, and substrate surface microarchitecture. In order to assess the feasibility of directing stem cell differentiation via microenvironment regulation, we have developed a murine embryonic stem cell (ES) alginate poly-L-lysine microencapsulation differentiation system. Our results indicate that the alginate microenvironment is biocompatible, is conductive to ES cell differentiation, and maintains differentiated cellular function. In addition, changes in alginate concentration and cell seeding density have proven effective in modulating differentiation as well as mature hepatic function.
Animal Viruses, Bacteria, and Cancer: A Brief Commentary

Animal viruses and bacteria are ubiquitous in the environment. However, little is known about their mode of transmission and etiologic role in human cancers, especially among high-risk groups (e.g., farmers, veterinarians, poultry plant workers, pet owners, and infants). Many factors may affect the survival, transmissibility, and carcinogenicity of these agents, depending on the animal-host environment, hygiene practices, climate, travel, herd immunity, and cultural differences in food consumption and preparation. Seasonal variations in immune function also may increase host susceptibility at certain times of the year. The lack of objective measures, inconsistent study designs, and sources of epidemiologic bias (e.g., residual confounding, recall bias, and non-randomized patient selection) are some of the factors that complicate a clear understanding of this subject.
Bloodstream Infection Caused by Nontoxigenic Corynebacterium diphtheriae in an Immunocompromised Host in the United States

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.
Evolution of indocyanine green dye choroidal angiography

During the past three years, indocyanine green (ICG) fluorescence angiography has enjoyed an increasing popularity, especially among clinicians who treat age-related macular degeneration. Although the basic methodology for performing ICG angiography was developed and demonstrated in the early 1970s, nearly 20 years passed before the technology became commercialized for widespread clinical use. The developmental evolution of ICG choroidal angiography and its future clinical uses are discussed.
Effect of interfacial bonding on the strength of adhesion of elastomers. I. Self-adhesion

Two partially gelled (crosslinked) layers of elastomer were pressed into intimate contact and the gelation reaction was then taken to completion. By varying the extent of initial gelation, the degree of chemical interlinking was varied from zero, when two fully reacted sheets were pressed together, up to a level characteristic of the final density of molecular linking within each layer, when they were brought together before any reaction had occurred. The strength of adhesion between the layers was measured under threshold conditions, i.e., at low rates of peel, at high temperatures, and, in some instances, with the layers swollen with a compatible liquid. Linear relations were obtained between the threshold work of detachment per unit of interfacial area and the amount of chemical interlinking, deduced from the kinetics of molecular linking within each layer. At any degree of interlinking, ranging from zero to the fully interlinked state, the work of detachment was lower for networks composed of shorter molecular chains, in accordance with the Lake–Thomas theory for the threshold strength of elastomer networks. By extrapolation to the fully interlinked state, the strength of adhesion corresponding to cohesive rupture was inferred. These values agreed with measured tear strength for polybutadiene gelled by a free-radical process. For a sulfur crosslinking system, and for both free-radical and sulfur crosslinking of poly(ethylene-co-propylene), the threshold tear strength of the elastomer was found to be much higher than the extrapolated value from adhesion measurements. This discrepancy is ascribed to roughness of the tear plane in relatively strong elastomers, in contrast to the smooth separation of flat adhering layers. Adhesion of fully crosslinked sheets was generally low, 1–2 J/m2. Higher values, 5–25 J/m2, were found with sulfur crosslinking systems, especially those yielding a high proportion of polysulfidic crosslinks. Interlinking via polysulfide crosslink interchange reactions is suggested in these cases.
Multiple selection pressures influence Trinidadian guppy (Poecilia reticulata) antipredator behavior

Animals alter their behavior to avoid a variety of different types of predators. Trinidadian guppies (Poecilia reticulata) have been an important system for examining the evolution of antipredator behavior because geographically isolated populations experience different amounts of aquatic predation. Although the influence of aquatic predators has been well documented, selective pressures from other types of predators are less well understood. We examined the response of wild-caught individuals from upstream and downstream populations to an aquatic predator and a simulated aerial predator. As previously documented, fish from the downstream population responded more strongly to the aquatic predator than did fish from the upstream population, inspecting for longer periods of time. Guppies also exhibited a strong behavioral response to the potential aerial predator. Although both populations displayed a similar magnitude of response, they differed in the specific behaviors used. Upstream fish tended to freeze on the tank bottom, whereas downstream fish tended to hide under shelter. Field observations suggest that these strategies are related to habitat features specific to each site. The behaviors used against aerial predators differed substantially from the behaviors used against aquatic predators, suggesting that different types of predators exert conflicting selection pressures. This research demonstrates the importance of considering multiple selection pressures acting on an organism when trying to understand the evolutionary history of behavioral and morphological traits. Key words: aerial predators, aquatic predators, fish, guppy. [Behav Ecol 15:673–678 (2004)]
A modern pollen rain study from the central Andes region of South America

Aim To provide a greater understanding of the modern pollen rain for the central Andes region of South America, thus laying the groundwork for future pollen studies and the derivation of pollen-climate transfer functions and response surfaces.
A comment on fermionic tachyons and poincaré representations

Abstract We extend Wigner's work on the wave equations for integer-spin particles to the spinorial case. A recent suggestion that the neutrino might be a fermionic tachyon is examined. We point out that a four-component Dirac equation cannot describe a fermionic tachyon.
Interaction of monodisperse anionic amphiphiles with the i-face of secreted phospholipase A2.

Pancreatic IB phospholipase A2 (PLA2) forms aggregates of defined size with monodisperse alkyl sulfates in the premicellar concentration range. As an extension of the interfacial kinetic paradigm, results are interpreted in terms of a model in which several amphiphile molecules bind along their polar headgroup to the interface binding region (i-face) of PLA2. The resulting complex, E # , has a half-micellar structure, and it acts as an "amphiphile" in the aqueous phase. E # not only self-aggregates but also binds hydrophobic probes and interacts with hydrophobic surfaces. As expected, resonance energy transfer from the tryptophan donor in PLA2 to an acceptor probe partitioned in E # shows a biphasic dependence as the probe coexisting with PLA2 is diluted at higher alkyl sulfate concentrations. The gel-permeation behavior of PLA2 at premicellar alkyl sulfate concentrations is also biphasic. For example, above 1.2 mM decyl sulfate (CMC ) 3.5 mM) PLA2 elutes as a single sharp peak, presumably the self-aggregate of E # with apparent molecular mass of 120-150 kDa. At 0.4-1 mM decyl sulfate the retention volume is even larger than that for the 14 kDa PLA2. This anomalous retention is attributed to the interaction of the hydrophobic region of E # with the hydrophobic patches on the gel-permeation matrix. Elution behavior of the self-aggregated E # form of site-directed mutants in dodecyl sulfate suggests that certain substitutions in the conserved hydrogen-bonding network have a significant effect on the aggregate size. These results suggest a role for the network in the amphiphile binding along the i-face of PLA2, presumably through a change in the anion coordination ligands.
Hormonal Control of Collateral Circulation

The possible regulatory effects of growth hormone and of cortisone on the development of pulmonary collateral vessels after ligation of one pulmonary artery were investigated in the rat. The weights of the animals were regulated so that they did not differ significantly in the control and experimental groups at the end of the experiment. The extent of the collateral circulation was judged by visual inspection and by weighing the casts. Animals injected with cortisone acetate intramuscularly in doses of 5 mg daily for two weeks and then maintained on an average dose of 15 mg weekly, had less development of collateral circulation at four and eight weeks than did controls. Animals injected with growth hormone in doses of 0.1 mg daily, had significantly larger collaterals than did controls at eight but not at four weeks, as determined by the visual ranking method. These results indicate 1) that there can be chemical control of collateral circulation, and 2) that cortisone and growth hormone can influence the development of collateral vessels in part by mechanisms other than an effect on body weight.
Peach orchard studies utilizing fluidized bed material

Abstract Fluidized bed material (FBM, a coal/limestone combustion byproduct) was used as a lime substitute prior to establishment of a peach (Prunus persia L.) orchard. Growth and nutrition of the trees were generally unaffected by applied FBM, either broadcasted or incorporated, at rates up to three times the soil lime requirement. Leaf and fruit Ca concentration were not significantly effected by FBM additions when compared to limestone or a fertilized control. Minor differences between treatments were noted for some elements. The applied FBM was found to be a suitable substitute for limestone in establishing a peach orchard from the aspects of tree nutrition and expected effects in the soil; elevated pH and higher extractable Ca status.
Information-theoretic algorithms in bioinformatics and bio-/medical-imaging: A review

Information-theoretic notion of entropy (in Shannon sense) is a versatile avenue in analyzing bioinformatic details as well as in mining data pertinent to molecular biology. Also, the informatics of bio- and medical-imaging can be comprehended via entropy considerations. Presented in this paper is a comprehensive review on salient methods, newer techniques and open-questions on unexplored efforts vis-a-vis the entropy principles cast on bioinformatic computations and bio-/medical-image informatics. Supplementing energetics algorithms are indicated
A STRUCTURALLY BASED ANALYTIC MODEL OF GROWTH AND BIOMASS DYNAMICS IN SINGLE SPECIES STANDS OF CONIFERS

A theoretically based analytic model of plant growth in single species conifer communities based on the species fully occupying a site and fully using the site resources is introduced. Model derivations result in a single equation simultaneously describes changes over both, different site conditions (or resources available), and over time for each variable for each species. Leaf area or biomass, or a related plant community measurement, such as site class, can be used as an indicator of available site resources. Relationships over time (years) are determined by the interaction between a stable foliage biomass in balance with site resources, and by the increase in the total heterotrophic biomass of the stand with increasing tree size. This structurally based, analytic model describes the relationships between plant growth and each species' functional depth for foliage, its mature crown size, and stand dynamics, including the self-thinning. Stand table data for seven conifer species are used for verification of the model. Results closely duplicate those data for each variable and species. Assumptions used provide a basis for interpreting variations within and between the species. Better understanding of the relationships between the MacArthur consumer resource model, the Chapman-Richards growth functions, the metabolic theory of ecology, and stand development resulted.
The phonology of the velar glide in Axininca Campa

Three important strands of research characterise modern phonological theory; (i) the cyclic interaction of morphology and phonology; (ii) prosodic structure as it is built from segments into moras, syllables, feet and ultimately the phonological word; and (iii) the precise internal structure of segments, including feature geometry, how these features may reside on autosegmental tiers, and how they may be underspecified.
Chapter 7 Applications of Judgment Analysis and Cognitive Feedback to Medicine

Publisher Summary This chapter describes some of the striking results of application of social judgment theory (SJT) to medical judgment. Clinical judgment traditionally has been considered an intuitive process whereby the physician combines patient history, new observations, and test results to form a diagnosis or plan of treatment. Medical judgments are characterized by uncertainty, subtle clues, and soft data. Judgment can be studied in different areas of medicine, the diagnosis, and in management of depression. Judgment in psychiatry is often thought to involve a high degree of the “art” of medicine, and as such, is a fertile ground for studying variation in physician judgment. One of the contributions of social judgment theory to medical judgment research has been to identify factors important to physicians in making clinical decisions. Policy capturing may identify heavily weighted clinical variables that would not have been found had the investigators relied on clinicians self reports. In many judgment settings, it is difficult if not impossible to determine the correct outcome of a given case.
Quinone Anion Bands in A1−/A1 FTIR Difference Spectra Investigated Using Photosystem I Particles with Specifically Labeled Naphthoquinones Incorporated into the A1 Binding Site

Time-resolved step-scan Fourier transform infrared difference spectroscopy (TRSS FTIR DS) has been used to produce A1 −/A1 FTIR difference spectra for menB photosystem I (PS I) particles from Synechocystis sp. 6803 (S6803) that have a 2-methyl naphthoquinone (2MNQ) occupying the A1 binding site. 2MNQ is the same as phylloquinone (PhQ) except that the phytyl chain is replaced with a hydrogen atom. We have also obtained spectra for PS I particles containing 2MNQ that is 18O labeled, and specifically 13C1 or 13C4 labeled. These spectra allow a demarcation between bands associated with the quinone and bands associated with other molecular groups in the binding site. To aid spectral interpretation we have also obtained FTIR absorption spectra for all labeled and unlabeled quinones, and have used density functional methods to calculate the FTIR absorbance and “anion minus neutral” absorbance difference spectra for all of the quinones studied.
Grapevine Xylem Development, Architecture, and Function

Secondary xylem vessel elements within the stems of grapevine (Vitis vinifera L.) mature over several weeks and stems maintain a large proportion of living vessel elements throughout most of the growing season. Only approximately one-third of secondary vessels within current-year growth are active at any single time. Once hydraulically active, the vessels of grapevine are highly susceptible to cavitation, consistent with the physiological response of most grapevine varieties to water stress. Nonconductive vessels may become blocked with either gels or tyloses. Large seasonal changes in both cavitation resistance and hydraulic conductivity occur in V. vinifera and may also be found along the length of a single stem, suggesting that the xylem may be able to dynamically respond throughout the season as growing conditions change. The high proportion of living vessels may be one of the reasons why interpretation of in situ imaging for grapevine has been difficult. Examination of the decline in the proportion of active vessels in response to water stress using traditional staining techniques confirms the high susceptibility of grapevine vessels to water stress and highlights the need for continued histological study of Vitis as new imaging technologies are developed.
Towards a Verified Artificial Pancreas: Challenges and Solutions for Runtime Verification

In this paper, we briefly examine the recent developments in artificial pancreas controllers, that automate the delivery of insulin to patients with type-1 diabetes. We argue the need for offline and online runtime verification for these devices, and discuss challenges that make verification hard. Next, we examine a promising simulation-based falsification approach based on robustness semantics of temporal logics. These ideas are implemented in the tool S-Taliro that automatically searches for violations of metric temporal logic (MTL) requirements for Simulink(tm)/Stateflow(tm) models. We illustrate the use of S-Taliro for finding interesting property violations in a PID-based hybrid closed loop control system.
Transnational Comparative Analysis of Balancing Competing Interests in Counter-Terrorism

Finding a balance between national security and the rights of individuals is the most significant issue faced by liberal democratic nations in developing their counter-terrorism strategy. Without a balance between these two tensions, democratic societies lose the very ethos for which they fight. As Benjamin Franklin once said, "those who would give up essential liberty, to purchase a little temporary safety, deserve neither liberty nor safety." Indeed, it is imperative for democracies to avoid infringing on political freedoms and civil liberties. Yet, the ultimate responsibility of government is to protect its citizenry. The struggle to balance competing interests is the fundamental dilemma confronting democracies today. Balancing will be addressed by analyzing how each of the five nations surveyed in this article (US, Israel, Russia, Spain and India) respond to major terror attacks. Balancing legitimate national security needs against the rights of those individuals living in the nation is a true test of a nation's adherence to democratic values. How each of the five surveyed nations balance will be the focus of this article. The discussion focuses on one particular issue in each of the reviewed countries, demonstrating how each of the five societies surveyed in this article balances national security and individual rights. Each issue is used as an example of how that nation balances. Liberal democratic societies that unilaterally decide on "self-imposed restraints," inherently limit their responses to terrorism. Unlike regimes which act with impunity and disregard norms, the surveyed nations understand that there are limits to power.
Penalized spaces: The ghetto as prison and the prison as ghetto

Even for those who have been following Loic Wacquant's work over the last decade, and for whom Urban Outcasts may offer no surprises, the publication of this intense, eloquent, timely and damning b...
Host Defenses Associated with Fruit Infection by Colletotrichum Species with an Emphasis on Anthracnose of Blueberries

Abstract Defense mechanisms in fruit against invasion by fungal pathogens fall into several categories, including fruit physiological factors, passive defense responses, and active defense response...