cssi/SciSciGPT-SciSciNet huggingface dataset:
Molecular epidemiology, biomarkers and cancer prevention

Molecular epidemiological studies within the field of cancer research provide the potential for elucidating the carcinogenic cascade at the molecular level. Identification of susceptible subsets of the population, based on polymorphisms in genes involved in carcinogenesis, has the potential to delineate more clearly those factors that might increase cancer risk among some, but not all, individuals. Rapid advances in human genomics are making it possible to develop detailed profiles of susceptible subgroups based upon genetic variants in multiple pathways. Here we discuss examples of recent susceptibility studies involving genes, such as those involved in carcinogen metabolism, DNA repair, cell cycle and immune status, that hold the promise of increasing our understanding of cancer etiology and possible prevention strategies.
Conducting Health Research in Korean American Churches: Perspectives from Church Leaders

Korean Americans experience many challenges to obtaining adequate health care coverage and access to needed services. Because a large proportion of Korean Americans attend churches on a regular basis, churches may be a promising venue where health programs can be delivered. In order to gain an in-depth understanding of Korean American churches with respect to conducting future health intervention research, we conducted exploratory interviews and focus groups with 58 leaders from 23 Korean American churches and three community organizations. From these interviews and focus groups, we found that Korean churches and church leaders seek to meet a variety of social and health needs of their congregation and their surrounding community. Several leaders have stated that assisting with social and medical needs of their members is an important component of their current ministry. They described profound health needs of their congregations and have suggested various ways in which the university can partner with the local churches to help address these needs through research. Additionally, they described various resources churches can provide to researchers such as: their personal assistance, church volunteer base, church facility, and church network and contacts. Our findings suggest that Korean churches have a high potential to serve an important role in the health of Korean Americans. On the basis of the promising results of the present study, we are planning to conduct a cross sectional survey of Korean church leaders and members in Los Angeles County to substantiate our findings in a larger representative sample.
More on “The Burdens of the New Curricularist”

The historical curriculum field in North America is a fairly well documented affair. As I indicated in "The Burdens of the New Curricularist," it is largely embodied in the work of a variety of thinkers who vied for some identification and influence in the experience of the public school. The participants largely were scholars who had theoretical ideas that had practical consequences in a project that was dedicated to using the school as an instrument for the advancement of society. The resulting struggle to shape the school curriculum has given us a legacy of thought that has come together to comprise the field of curriculum. The general thrust of the field was largely about doing curriculum work, not just thinking or writing about how it might be done. This is a historical position that is documented and debated, not simply proclaimed. Let me urge the readers to examine the work of Daniel Tanner and Laurel Tanner (1995) as they have made the case for an emerging paradigm in the curriculum field and to take a close look at some of the debate that exists on the topic (Barrow 1988; Jickling 1988; Tanner and Tanner 1998). The point of my original essay was that the field has a history we all inherit. The piece was not aimed at formulating the future of the field, notwithstanding my call for a restoration, and it certainly was not about articulating a model for curriculum development. It was a criticism targeted at a new generation of scholars that claims, as my colleague William Wraga once put it, to be in the field of curriculum without being of the field of curriculum. I tried to explain what I believe it means to be of the field, as it has taken shape historically. One might, of course, examine this history and conclude that it is time to completely alter the nature of the field's historic mission. But if such a proposition is to be undertaken, it has to be undertaken argumentatively, by confronting the issues and showing that the history of the field has been somehow misdirected or that the central tenets of the field, which I assert are centered around the issues of school practice and school design, are no longer viable. These are the burdens of the new curricularists, the historical weight that they refuse to carry and that they cavalierly discard. You have probably read how Pinar responded to my original piece. He ignored it. Presumably, the editors of Curriculum Inquiry put Pinar under no obligation to actually attend to my
Measurement invariance in training evaluation: Old question, new context

Technological advances that have been put to use by organizations have not escaped the training domain. With the shift towards computer-mediated surveys, training evaluations have been converted from traditional paper-and-pencil formats to Web-based environments. This begs the question as to whether or not these modalities are equivalent. Accordingly, this study examined the item functioning of parallel Web-based training evaluations and traditional paper-and-pencil evaluations of a training intervention. Item response theory (IRT) analyses revealed few differences between how an individual would respond to particular items (i.e., differential item functioning) regardless of the modality employed to complete a training evaluation. This provides evidence for the equivalence of paper-and-pencil and computer-mediated training evaluations.
Security automation considered harmful

End-users are often perceived as the weakest link in information security. Because of this perception, a growing body of research and commercial activity is focused on automated approaches to security. With these approaches, security decisions are removed from the hands of the users, and are placed instead in systems themselves, or in remote services or organizations that establish policies that are automatically enforced. We contend that although security automation is potentially beneficial in theory, in practice it is not a panacea for end-user information security. A number of technical and social factors mitigate against the acceptance and efficacy of automated end-user security solutions in many cases. In this paper, we present a discussion of the inherent limitations of automating security for end-users. We then discuss a set of design guidelines for choosing whether to automate end-user security systems. We conclude with a set of research directions focused on increasing the acceptance and efficacy of security solutions for end-users.
Amylase activity in sterile spoiled pudding

Ultrahigh temperature sterilized canned puddings occasionally exhibit spoilage in the form of a dramatic loss of viscosity or thinning. Studies on a concentrated fraction of spoiled pudding indicate that thinning was due to a heat-resistant amylase. The concentrate was obtained by centrifugation and ultrafiltration of the thinned pudding. Ultrafiltration characteristics of the active agent indicate a molecular weight of 1–30 × 104 daltons. The agent attacked starch with a decrease in iodine-binding capability and an increase in reducing units. Treatment of the concentrate with proteolytic enzymes decreased enzymatic activity by 50%; treatment with sodium ethylene diaminetetraacetate decreased activity by 80%. The levels of starch and pH of the spoiled puddings were suitable for action of the amylase, and the enzyme was quite active at normal and elevated room temperatures.
Galanin potentiates electrical stimulation and exogenous norepinephrine-induced contractions in the rat vas deferens.

Abstract In order to evaluate the mode of action of galanin (GAL) on the neuroeffector mechanism of peripheral sympathetic nerve fibers, the effects of this peptide were tested on the electrical stimulated and the unstimulated preparations of the isolated rat vas deferens in the presence of 10−7 M atropine. The contractile responses, which were mediated predominantly by activation of postganglionic noradrenergic nerve fibers were dose-dependently potentiated by GAL in concentrations ranging from 1 to 50 nM. The facilitatory action induced by GAL in high concentrations (> 10 nM) usually returned to the control level at 2–3 min and were tachyphylactic. The potentiating action of GAL was not modified by pretreatment with 10−7 M propranolol. Contractions produced by exogenous norepinephrine (NE) in the unstimulated preparations were not affected by pretreatment with low concentrations ( 10 nM) of GAL, which recovered 15 min after constant flow washout. Contractions developed by exogenous 5-hydroxytryptamine were not affected, or slightly inhibited, by GAL (1–50 nM). In some preparations without electrical stimulation, high concentrations of GAL caused a slight contraction, which was not blocked by pretreatment with 10−6 M phentolamine and 10−6 M tetrodotoxin. These results suggest that GAL receptors exist presynaptically in the rat vas deferens and that stimulation of the receptors by GAL potentiates the release of NE from the nerve terminals during postganglionic sympathetic nerve stimulation. Other mechanisms for GAL action, such as influence on neuronal uptake and catecholamine metabolism, cannot be ruled out.
The Distributional Impacts of Privatization in National Water-Quality Policy

This research addresses the role of privatization in a major national environmental program and the implications of that involvement on the ability of the program to meet national policy objectives. The study draws a distinction between "formal" and "informal" privatization and suggests that informal privatization may result in less desirable public outcomes. Using data from a 50-state study of the State Revolving Loan Fund program, a series of multivariate models are developed and tested to determine the effects of privatization on the distribution of loans to certain kinds of applicant communities. The study finds that private sector activity in the State Revolving Loan Fund program results in significantly different patterns of resource distribution in the program, in that states engaging in informal privatization are less likely to meet the national policy objectives of the program than those engaging in formal privatization.
Rheumatoid synovial cell hormone responses modulated by cell-cell interactions

Cellular interactions within the rheumatoid synovium are likely to be responsible for the destructive properties of this tissue. The responses to hormones which regulate connective tissue metabolism may also be influenced by these cell-cell interactions. To determine the effect of cellular interactions on responses to hormones, human peripheral blood mononuclear cells were cocultured with adherent rheumatoid synovial cells. Coculture resulted in a decrease in response to prostaglandin E2 as assessed by a reduction in the magnitude of the acute prostaglandin-induced cyclic AMP response. In contrast, coculture resulted in an increase in the magnitude of the acute parathyroid hormone-induced cyclic AMP response. The decrease in response to prostaglandin was reversed by the presence of indomethacin during the preincubation, whereas indomethacin had no effect on the cyclic AMP response to parathyroid hormone. Increases in endogenous synovial cell prostaglandin production (stimulated by soluble factors released by the mononuclear cells) accounted for the subsequent decrease in the response to exogenous prostoglandin. The increase in cyclic AMP response to parathyroid hormone could not be explained by a soluble factor and was independent of ambient prostaglandin levels.
Public support for emergency (anti‐terrorist) legislation in Northern Ireland: a preliminary analysis

Abstract Anti‐terrorist legislation in the United Kingdom is premised upon the assumption that the existence of special criminal procedures for terrorist offenses will not affect how citizens evaluate the legitimacy of the legal process and of legal institutions more generally. I examine the implications and question the plausibility of that assumption in this article. For my analysis, I shall rely upon public opinion data concerning the extent to which Roman Catholics and Protestants support the emergency legislation and special courts in Northern Ireland. My findings suggest, contrary to the assumptions upon which the emergency legislation is predicated, that certain aspects of the emergency legislation have seriously eroded public confidence in the administration of criminal justice in Northern Ireland. This finding has considerable significance for societies that hope to control political terrorism by relying upon modified versions of the rule of law.
MM2 Designing Computer Models to Convey Cost-Effectiveness Analyses Results

Results from economic analyses of the effectiveness of new therapeutic innovations determine whether a new product will be reimbursed by a managed care organization or government agency. Often, the results of these economic analyses are presented as formal empirical analyses in scientific journal articles. With the pace of medical innovations submitted for approval on a payers fee schedule or formulary list ever increasing, it is important to convey the results of analysis as effectively and efficiently as possible. In response, interactive computer models have been developed to present the key findings of an economic analysis. Ideally, these models allow a potential buyer to customize a scientific analysis to determine their own reservation price for a new product. The quality and costs of these software applications vary-geatly. Given the resources expended to develop these models and time to produce them, it useful to examine the features of cost-effective “laptop model” design. This workshop will review an inventory of the features of laptop models. Participants will gain an understanding of the development process and costs for developing these models from the conceptual development phase to production of a stand-alone software application. A checklist of critical ingredients for software development will be reviewed with a special focus on role of a multidisciplinary development team and the capital resources required. A review of the discordance between scientists, biomedical manufactrures, software applications developers and potential clients and methods to gain consensus to build the application will be discussed. Examples from Project HOPE's and other firms' software development initiatives will be demonstrated as successful applications currently in use. Participants with a basic knowledge of computer applications, cost-effectiveness methods, and systems analysis will likely gain the most from this workshop.
Segregation of cells that differentiated without cell movement from a single precursor population.

Abstract Previous studies have demonstrated that limb cartilage and limb muscle arise from the mesenchyme cells of the early limb bud without any detectable cell movement. In the present study, binary mixtures of these three cell types have been made in order to determine whether cells gain the ability to segregate as part of the differentiative process. Limb cartilage, limb muscle, and limb mesenchyme can each segregate from the other two cell types. Thus, the ability to segregate is, in this case, a differentiative characteristic.
PRODUCTION OF AORTIC THROMBOSIS IN RABBITS.

SummaryExposure of the abdominal wall to injured skeletal muscle produces thrombosis in 50% of old rabbits and young rabbits pretreated with large doses of vit. D. Young untreated rabbits are resistant to thrombus formation by this method.
Circadian rhythms in Neurospora crassa: the effects of point mutations on the proteolipid portion of the mitochondrial ATP synthetase.

Five oligomycin-resistant (oli r) mutant strains of Neurospora crassa were analyzed for their growth rate and for the periodicity of their circadian rhythm. The most resistant strains had periods of 18–19 h while the least resistant strain had a normal period of 21.0 h. There was a rough correlation between the in vivo degree of oligomycinresistance and the amount of change in the period. Several of the oli r mutations have been previously described by Sebald et al. (1977) in terms of known amino acid changes in the primary structure of the proteolipid, or DCCD-binding protein, found in the F0 membrane portion of the mitochondrial ATP synthetase. Amino acid changes in the structure of this protein are reported here for two other oli r mutations. The proteolipid isolation procedures were slightly modified to include a delipidation step, and an HPLC procedure was developed to separate the hydrophobic peptides of this protein. Analysis of heterocaryons carrying both the oli r and oli s markers indicated that the oli r and oli s mutations were codominant to each other in terms of period and growth rate. The changes in the primary structure of this DCCD-binding protein reported here are the first known examples of changes in the primary structure of a protein which alter the period of a circadian rhythm.
The RACE Open Services Architecture project

The specification and implementation of current telecommunication services tend to be intimately bound to a specific network architecture. Moreover, within the service software, interactions between the logical modules are not always explicit, accessible, or uniform, and tend to be optimized for a particular service. This is exemplified by the difficulty experienced in integrating equipment from multiple vendors, and has resulted in telecommunication systems that cannot rapidly exploit the advantages of new technology or respond to changing customer requirements. In addition, current telecommunication services tend not to be viewed as an integral whole, whereby user, control, and management aspects of a service are developed independently from one another. Separate development can lead to problems of inconsistency if shared data are not updated correctly. The RACE Open Services Architecture (ROSA) project was established to address these problems. This paper presents an overview of the approach taken in the ROSA project.
Photosensitization by synthetic diporphyrins and dichlorins in vivo and in vitro.

— A group of polycarboxylic diporphyrins, two dichlorins and a porphyrin-chlorin dimer, with rings linked by methylene groups, were examined to help identify structures which can mediate photodynamic tumor eradication in vivo. Among the features sought were short persistence of normal tissue photosensitization and substantial absorbance at wavelengths longer than 630 nm. Both objectives were achieved, with pertinent structure-activity relationships partly characterized. The relative hydrophobicity of the different sensitizers was an important determinant of their accumulation in cell culture, but not of in vivo effectiveness. These compounds showed affinity for protein and high-density lipoprotein components of serum. Their distribution may be mediated by a different mechanism than that which occurs with more hydrophobic sensitizers like hematoporphyrin derivative which have greater affinity for low-density lipoproteins and less for protein components of serum, as compared with the products examined in this study.
Further evidence that conditioned inhibition is not the mechanism of an extinction cue's effect: A reinforced cue prevents spontaneous recovery

Previous research has demonstrated that discrete cues presented during extinction of a conditioned response (extinction cues) subsequently reduce spontaneous recovery and the renewal effect. In order to assess whether an extinction cue’s effect is due to conditioned inhibition, the effect of pairing an extinction cue with food on the cue’s capacity to modulate spontaneous recovery was investigated in an appetitive conditioning experiment with rats. Conditioned inhibitors paired with the unconditioned stimulus lose their potential to inhibit responding. The food-paired extinction cue did not lose its potential to reduce spontaneous recovery. In fact, it reduced spontaneous recovery more than did an extinction cue that was not paired with food. The results indicate that extinction cues attenuate postextinction recovery of conditioned responding through a mechanism other than conditioned inhibition. The cue’s action appears to be similar to that of serial negative occasion setters. Theories of spontaneous recovery and the relationship of extinction cues to other modulatory stimuli are discussed.
Biological Ice Nucleation Activity in Lichen Mycobionts and Photobionts

Axenic cultures of lichen mycobionts and photobionts were assayed for biological ice nucleation activity (INA), a characteristic which has recently been discovered in some species of lichens collected from nature. Of 14 species of mycobionts, five showed nuclei active at −5°C or warmer, while none of the 13 photobionts tested had INA at that temperature. It appears that biological ice nuclei in lichens are produced primarily by the mycobiont. Rhizoplaca chrysoleuca had the greatest INA. Other lichen fungi showing warm temperature INA were Cladonia boryi, Cladonia rangiferina, Lecanora dispersa, and Pertusaria flavicans. Lichen INA may be involved in moisture uptake and/or frost protection.
Lectin-mediated agglutination of murine lymphoma cells. Cell surface deformability and reversibility of agglutination by saccharides.

Agglutination of S49 mouse lymphoma cells by Ricinus communis I agglutinin can be reversed by the competing haptenic saccharide, lactose, soon after agglutination, but after further incubation in the absence of lectin the agglutination reaction could not be reversed by lactose and the cells remained as multicell aggregates. The irreversibility of S49 cell agglutination was time, temperature and lectin concentration dependent and its onset correlated with ultrastructurally observed deformation of adjacent cell surfaces and an increase in the proportion of adjacent cell surface areas in close apposition within multicell aggregates. Pretreatment of S49 cells with cytochalasin B or cytochalasin B plus vinblastine enhanced R. communis I agglutinin-mediated agglutination, while vinblastine alone and fluoride plus azide had essentially no effect. When drug-treated cells were agglutinated and then incubated in lectin-free drug-containing media for various times prior to lactose addition, the drug effects were more pronounced. Cytochalasin B alone or with vinblastine inhibited lactose reversal of S49 cell agglutination compared to the drug-free controls, while fluoride plus azide enhanced hapten reversibility. Electron microscopic analysis revealed that the onset of agglutination irreversibility correlated with cell surface deformation in the drug-treated cells. Cell aggregates that were more readily reversible by lactose (fluoride plus azide) were unchanged or less deformed, while S49 aggregates treated with cytochalasin B plus vinblastine were more deformed compared to controls without drugs. These experiments suggest a role for cell surface deformability as an important secondary effect during lectin-mediated cell agglutination of 849 lymphoma cells.
Energy- and angle-differential yields of electron emission from thin carbon foils after fast proton impact

Proton-induced electron emission from sputter-cleaned thin carbon targets was investigated under ultrahigh vacuum conditions using time-of-flight energy analysis. These data emphasized the low-energy portion, e.g., {ital E}{sub {ital e}}{lt}20 eV, of the spectrum. Energy distributions of the emitted electrons were measured as a function of the emission angle, impact energy, and foil thickness. {copyright} {ital 1996 The American Physical Society.}
The one-pion-exchange potential in the three-body model of nucleon-nucleon scattering

Abstract We derive the one-pion-exchange potential in the three-body model of nucleon-nucleon scattering in which the nucleon is treated as a bound state of a pion and a nucleon, and show that it has the same form as the usual Yukawa OPEP derived from field theory, except that its range is energy dependent and it becomes complex above the pion-production threshold.
Prerecruitment organizational perceptions and recruitment website information processing

Despite the prevalent use of the Internet for recruitment purposes, little is known about how job seekers process presented information, particularly before organizations have actively recruited these job seekers. In this study, we examine the effects of prerecruitment perceptions of familiar organizations before exposure to information on organizational recruitment websites using a combination of undergraduate students and employees of a large university located in the southwestern USA (N = 75). Participants completed a three-part study that allowed us to investigate how these prerecruitment perceptions impact the reported time spent viewing recruitment websites and the ability to recall website information. We used two hierarchical moderated multiple regression models to test study hypotheses. Our results suggest that job pursuit intentions may influence processing of job and organizational information presented on recruitment websites, and this influence is moderated by subjective fit perceptions. Spec...
Endothelium-derived nitric oxide regulates systemic and pulmonary vascular resistance during acute hypoxia in humans

Abstract Objectives. This investigation sought to determine whether endothelium-derived nitric oxide contributes to hypoxia-induced systemic vasodilation and pulmonary vasoconstriction in humans. Background. Endothelium-derived nitric oxide contributes to basal systemic and pulmonary vascular resistance. During hypoxia, systemic vasodilation and pulmonary vasoconstriction occur. There are some data indicating that endothelium-derived nitric oxide mediates changes in vascular resistance during hypoxia, but much of it is contradictory, and none has been derived from normal humans. Methods. The hemodynamic effects of NG-monomethyl- L -arginine ( L -NMMA), a nitric oxide synthase inhibitor, were studied in healthy volunteers under normoxic and hypoxic conditions. A Swan-Ganz catheter and radial artery cannula were inserted to measure right atrial, pulmonary artery, pulmonary capillary wedge and systemic blood pressures. Cardiac output was measured by thermodilution. Systemic vascular resistance and pulmonary vascular resistance were calculated. The pharmacokinetics of L -NMMA (300 mg intravenously) was studied during normoxia in six subjects. Hypoxia was induced in eight subjects who inspired a mixture of nitrogen and oxygen through a gas blender adjusted to reduce the partial pressure of oxygen from (mean ± SE) 98 ± 4 to 48 ± 1 mm Hg. Results. During normoxia, L -NMMA increased systemic vascular resistance from 1,108 ± 74 to 1,705 ± 87 dynes·s·cm−5 and increased pulmonary vascular resistance from 60 ± 5 to 115 ± 9 dynes·s·cm−5 (p ≤ 0.01 for each). Peak effects occurred within 10 min of L -NMMA administration. Acute hypoxia alone decreased systemic vascular resistance from 1,209 ± 78 to 992 ± 58 dynes·s·cm−5 (p ≤ 0.05) and increased pulmonary vascular resistance from 92 ± 11 to 136 ± 4 dynes·s·cm−5 (p ≤ 0.01). While hypoxic conditions were maintained, infusion of L -NMMA increased systemic vascular resistance (to 1,496 ± 97 dynes·s·cm−5, p ≤ 0.01) and increased pulmonary vascular resistance further (to 217 ± 25 dynes·s·cm−5, p ≤ 0.01). Conclusions. Endothelium-derived nitric oxide contributes to systemic vasodilation and serves as a counterregulatory mechanism to attenuate pulmonary vasoconstriction during acute hypoxia in healthy human subjects.
Nanoindentation for measuring individual phase mechanical properties of lead free solder alloy

The elimination of lead from electronics due to its detrimental effects to environment and health is pushing component manufacturers to consider lead free solder alloys as the substitute. Application of such alloys requires a better understanding of their mechanical behavior at small volume size and at elevated temperatures. Such information is still lacking for both solder joints and bulk materials. In this study, nanoindentation technique was used to investigate the mechanical properties, namely the hardness and Young’s modulus, of the constituent phases in a near eutectic ternary SAC387 lead free solder alloy. The indentation-induced piling-up of the soft Sn phase was accounted for in the nanoindentation mechanical property calculations using a semi-ellipse method. The modified results agreed well with previous studies on similar alloys. Also, finite element simulation was used to estimate the effect of the complicated network between the eutectic Sn and the intermetallic phases on the mechanical properties acquired, which showed that the tested modulus of the intermetallic phase in the eutectic area exhibited considerable reduction. Vickers tests were also carried out at elevated temperatures, and the hardness of constituent phases dropped 35% from 25 °C to 85 °C.
Sampling of low molecular weight iron by microdialysis following spinal cord injury.

We combined the use of desferrioxamine as an iron chelator, microdialysis sampling, and iron analysis by atomic absorption spectroscopy to measure extracellular levels of low molecular weight (LMW) iron in vivo in the spinal cord. Low molecular weight iron is free iron plus iron bound to small molecules. We show that the extracellular LMW-iron concentration is not increased significantly in situ by trauma to the rat spinal cord, suggesting that an extracellular elevation in LMW-iron at the site of injury is not the major initiating factor for lipid peroxidation following spinal cord injury.
Treatment of Missing Data: Beyond Ends and Means

The ethical decision making process behind the treatment of missing data has yet to be examined in the research literature in any discipline. The purpose of the current paper is to begin to discuss this decision-making process in view of a Foucauldian framework. The paper suggests how the ethical treatment of missing data should be considered from the adoption of this theoretical framework.
Autonomic dysfunction in dementia with Lewy bodies

Objective: To assess autonomic function in patients with dementia with Lewy bodies (DLB). Methods: The authors compared data from 20 DLB patients evaluated from 1995 to 2000 to 20 age-matched multiple system atrophy (MSA) and Parkinson disease (PD) patients evaluated from 1999 to 2002. Analysis of variance, Fisher exact test, and Student t -test were applied to compare disease characteristics, autonomic symptoms, and function tests on the Composite Autonomic Scoring Scale (CASS) and Thermoregulatory Sweat Test (TST). Results: In DLB, mean age at onset of autonomic symptoms was 70.3 ± 8.9 years. Orthostatic symptoms were common and orthostatic hypotension occurred in 10/20 DLB, 17/20 MSA, and 1/20 PD patients ( p = 0.023, 0.003). CASS-sudomotor for DLB, MSA, and PD were 1.6 ± 1.2, 2.5 ± 0.7, and 0.9 ± 0.8 ( p p p p Conclusions: Autonomic dysfunction is frequent in dementia with Lewy bodies and the severity is intermediate between that of multiple system atrophy and Parkinson disease.
Performance evaluation of channel access schemes in multihop packet radio networks with regular structure by simulation

Abstract The performance of various channel access schemes in multihop packet radio networks with a regular structure is studied by means of simulation. The channel access schemes considered are: ALOHA (pure and slotted), Carrier Sense Multiple Access (CSMA), Busy Tone Multiple Access (BTMA), Code Division Multiple Access (CDMA), and a new hypothetical scheme introduced here for comparison purposes referred to as Coded Activity Signalling Multiple Access (CASMA). Network throughput and packet delay are evaluated, as well as the effects on performance of the nodal transmission scheduling rate, the propagation delay among nodes, and to some extent the input flow control. In this study, we consider networks in which both the topology and the traffic pattern are symmetric. This render all nodes in the network statistically identical, and thus helps reduce the complexity of the simulation task considerably without jeopardizing the objective. The performance of CSMA in such networks in shown to be rather poor as compared with its performance in fully connected networks, while relatively high performance is achieved by the CASMA scheme, the various BTMA protocols, as well as the CDMA scheme, as compared with CSMA and the ALOHA schemes.
Knowledge from the Flies

Progress and Prospects in Evolutionary Biology: The Drosophila Model. JEFFREY R. POWELL. Oxford University Press, New York, 1997. xiv, 562 pp., illus. $70. ISBN 0-19-507-691-5.
Adaptive focusing through layered media using the geophysical "time migration" concept

Virtually all practical algorithms for aberration correction in medical ultrasound have thus far modeled the aberrating tissues with a thin time-delay screen. While this assumption is probably reasonable for small image regions (isoplanatic patches), practical application is still difficult. In many cases, an inability to estimate the screen parameters with sufficient accuracy in the presence of aberration and speckle targets has led to disappointing performance. A new aberration correction approach is proposed, inspired by the geophysical imaging concept of time migration. This technique is motivated by considering complete, bistatic, pulse-echo data acquired from layered media, where sound speed is a function of depth only. Reflection travel times as a function of source-receiver offset in such a model are approximately hyperbolic, just as they would be if the sound speed in the medium were constant and equal to the rms speed of the layers. Seismic imaging practice has shown this approximation to be robust in the presence of minor lateral speed variations. By focusing each point in the image using a constant sound-speed assumption, but allowing this assumed speed to change from point to point, a well-focused image may be obtained. A focusing criterion is all that is needed to determine the optimum focusing speed at each image point, without a priori knowledge of the medium properties. FDTD simulations provide synthetic data acquired from a 64-element array. A simple skull model was interposed between the array and targets in one simulation; in another, a speckle-producing region with embedded cysts was imaged through a Gaussian-shaped, high-speed anomaly. In both cases, images formed using different assumed sound speeds show different parts of the image in good focus. Application of the proposed focusing criterion produces a composite image showing improvement over any single image formed assuming a constant speed of sound.
Time Course of Spontaneous In Vitro Sperm Acrosome Reaction

The acrosome reaction (AR) is an exocytotic process essential for sperm penetration of the zona pellucida and binding to the oocyte (DeJonge, 1994). Evaluation of in vitro AR can suggest fertility potential. The purpose of this study was to determine AR as a function of time after removal of sperm from the seminal fluid using a novel test, the Acrobeads test (Fertility Technologies, Natick, Massachusetts), which uses paramagnetic beads coated with MH61, a monoclonal antibody that binds to acrosome-reacted sperm. Specimens were acquired from known fertile donors (n = 9) and in vitro fertilization (IVF) patients (n = 8) with no apparent male factor on the day of the IVF and processed by a minipercoll wash at 30 minutes after ejaculation. An aliquot of washed sperm was then divided into two portions. The first was placed with the Acrobeads (according to the manufacturer's instructions) and assessed for bead binding after 6 and 24 hours with the beads. The second aliquot of washed sperm was held at room temperature for 24 hours, then exposed to the beads, with bead binding assessed at 6 and 24 hours later (30 and 48 hours after washing). The Acrobeads score was determined by assessing the binding of MH61 beads in each of four replicates with a resulting score of 1 (lowest) to 4 (highest). The mean (+/-SD) motility was 62.0% (7.5) at 6 hours, 52.3% (6.4) at 24 hours, 55.9% (10.4) at 30 hours, and 54.7% (8.4) at 48 hours after removal from the seminal fluid. At 6 hours after washing and exposure to the beads, the score was 0.077 (0.27) with a range of 0-1; one donor specimen gave a score of 1, while all others had a score of 0. At 24 hours postremoval from the semen, donor and patient sperm were positive for the test, with a mean score of 3.6 (0.65). The mean fertilization rate for the IVF patients was 64.4% (range 33-90). When sperm were held for 24 hours prior to the test, there was little or no bead binding 6 hours later (score of 0.46 +/- 0.77) and at 24 hours later (48 hours after washing) (mean score of 0.25 +/- 0.45). These data suggest that completion of the acrosome reaction occurs by 24 hours after removal of the sperm from the seminal fluid. Since the MH61 beads bind to specific residues on the inner acrosomal membrane, these data also suggest that following the acrosome reaction at 24 hours with removal of the outer acrosomal contents and acrosomal matrix, the inner acrosomal membrane may be modified in some way that does not allow MH61 beads to bind to the sperm.
First and Second Language Reading Comprehension.

Random parallel reading comprehension tests in Japanese and English were administered to a sample of native Japanese students enrolled in intensive English instruction at three different levels of ...
Bipolar Outflows in Stellar Astrophysics

Hypersonic bipolar outflows are a ubiquitous phenomena associated with both young and highly evolved stars. Observations of Planetary Nebulae, the nebulae surrounding Luminous Blue Variables such as Eta Carinae, Wolf Rayet bubbles, the circumstellar environment of SN 1987A and Young Stellar Objects all reveal high velocity outflows with a wide range of shapes. In this paper I review the current state of our theoretical understanding of these outflows.
Increased Cytosine DNA-Methyltransferase Activity During Colon Cancer Progression

Background Molecular changes during progressive stages of colon cancer and other human tumors commonly involve altered regulation of DNA methylation. These changes include overall genomic hypomethylation, regional hypermethylation, and increased levels of messenger RNA (mRNA) for cytosine DNA-methyltransferase (DNA-MTase), the enzyme that catalyzes DNA methylation at CpG (cytosine-phospho-guanine) sites. This increase in DNA-MTase transcripts (mRNA), if accompanied by increased DNA-MTase activity, could play a role in the abnormal DNA methylation patterns that appear early in colon tumor progression. Purpose We sought to determine whether increased DNA-MTase mRNA levels during colon cancer progression are associated with increased cellular DNA-MTase enzymatic activity. Methods We adapted a microassay for DNA-MTase and used it to measure activity in human colon carcinoma and in colon mucosa of normal control subjects and of patients with colon cancer or with familial adenomatous polyposis (FAP), which is a risk factor for colon cancer. Steady-state DNA-MTase gene transcripts were measured by a reverse transcriptase polymerase chain reaction assay. To compare DNA-MTase activity with mRNA levels, we determined both variables simultaneously for one colon cancer specimen, its adjacent mucosa, and the colon mucosa of a control patient and compared the values. Results Compared with DNA-MTase activity in mucosa from normal control subjects, activity was elevated 1.4-fold in FAP mucosa, 1.6-fold in the uninvolved mucosa of patients with cancer, and 5.4-fold in the cancer specimens. All these differences were statistically significant. Fourteen of 15 cancer samples and 47% of the uninvolved adjacent mucosa samples had values that were higher than the highest value in normal mucosa. In one patient who had both a benign adenomatous polyp and a malignant adenocarcinoma, increasing DNA-MTase activity was observed at each stage of tumor progression. Conclusion These results demonstrate that an increased DNA methylation capacity accompanies the increase in DNA-MTase transcripts observed during progressive stages of colon cancer. Implication Further studies are needed to determine whether this abnormal methylation capacity plays a role in establishing the abnormal DNA methylation patterns seen in human malignancies.
Binary representation of cycle Tanner-graph GF(2/sup b/) codes

We derive the average symbol and Hamming weight spectrum functions of the random ensemble of regular low-density parity-check (LDPC) codes over GF(2/sup b/) when used with the binary-input noisy channel. This work confirms theoretically that the near-Shannon-limit performance of Gallager's binary LDPC codes can be significantly enhanced by moving to fields of higher order. We construct a family of error-correcting codes based on the binary representation of GF(2/sup b/) codes defined on a cycle Tanner graph that appears to be "good" for both optimum and iterative decoding over the binary-input noisy channel. In particular, we report a short-block-length (1008 bits), rate-1/2 progressive-edge-growth-based cycle Tanner-graph code over GF(2/sup b/) with a block-error rate <10/sup -4/ at E/sub b//N/sub 0/=1.89 dB, which appears to exhibit the best iterative-decoding performance at this short block length known to date.
Teaching so they hear: Using a co‐created diabetes self‐management education approach

Purpose: To describe the development and outcomes of a co-created diabetes self-management education (DSME) intervention that resulted in statistically significant (p= .02) improvements in diabetes self-care activities when compared to outcomes of a typical DSME program. Data sources: In this pilot study, an experimental self-management intervention with a self-selected group of adults with type 2 diabetes mellitus was held in the southern United States. Focus group results were used to develop the intervention and DSME participants co-created the sessions. Pre- and postintervention outcomes were compared to those of participants in DSME programs at two area, certified diabetes education centers. Conclusions: No significant differences were found between the experimental and control groups with regard to knowledge, adaptation, and program satisfaction. However, diabetes self-care activities significantly improved (p= .02) for the experimental group. Implications for practice: A co-created teaching approach better meets the learning needs of adults with type 2 diabetes mellitus and results in enhanced ability to perform the self-care activities required for successful diabetes control. Better diabetes control reduces visits to monitor and treat complications and the need for repetitive educational sessions that exceed third-party pay limits and extend the time needed for patient encounters.
Low Spurious, Broadband Frequency Translator Using Left-Handed Nonlinear Transmission Line

In this letter, we present a frequency translator based on a left-handed nonlinear transmission line (LH NLTL). The proposed LH NLTL can achieve a very linear phase variation as a function of applied dc bias for a broadband frequency that facilitates a low spurious, broadband frequency translation. Our experiment demonstrates that the LH NLTL enables frequency shift with 30 dB maximum spurious suppression. For any frequency between 3 and 3.8 GHz, it was possible to achieve 100 KHz-1 MHz frequency shift while the range of spurious suppression is between 21 and 30 dB. Because of its compactness and possibility of low-cost monolithic fabrication, this circuit will be very useful for microwave instrumentation, or a coherent communication system where single sideband modulation is required.
Photolysis of aromatic diisocyanate‐based polyurethanes in solution

Abstract : Fluorescence analysis has been employed as an analytical technique to elucidate the photolysis mechanism of several aromatic diisocyanate based polyurethanes in solution. Based on a comparison with model arylmonocarbamates and arylbiscarbamates, the photo-Fries rearrangement and cleavage-type products found for the small model arylcarbamates were also identified for the photolyzed polyurethanes in solution. Viscosity and absorbance change results for photolysis of both air and nitrogen saturated polyurethane solutions are consistent with a general two step mechanism for the photolysis of aromatic diisocyanate based polyurethanes.
Lipopolysaccharide induces expression of Egr-1 in macrophages through upstream CArG box (serum response) elements:

The protein product of the early response gene, Egr-1, is required for macrophage differentiation. Egr-1 mRNA is induced by lipopolysaccharide within minutes in murine peritoneal macrophages through an effect on the rate of transcription of Egr-1. Therefore, we undertook a series of studies to characterize Egr-1 protein induced by LPS and to define enhancer elements in the Egr-1 promoter which mediate the effect of LPS in murine macrophages. Salmonella minnesota Re 595 LPS (10 ng/ml or higher) induced Egr-1 protein of 80 kDa within 45 min in thioglycollate-elicited peritoneal macrophages. The promoter region of Egr-1 contains six serum response elements (SRE) which each contain a core CArG box. CAT activity in LPStreated macrophages transfected with Egr-1-CAT constructs containing the two most upstream 5' SREs was increased 4.7-fold whereas CAT activity in macrophages transfected with constructs lacking these two most upstream SREs was not affected by LPS. LPS induced CAT activity in macrophages transfect...
Barrett Esophagus and Risk of Esophageal Cancer: A Clinical Review

Importance Barrett esophagus, a complication of gastroesophageal reflux disease (GERD), predisposes patients to esophageal adenocarcinoma, a tumor that has increased in incidence more than 7-fold over the past several decades. Controversy exists regarding the issues of endoscopic screening and surveillance for Barrett esophagus, treatment for the underlying GERD, and the role of endoscopic eradication therapy. Objectives To review current concepts on the pathogenesis, diagnosis, and treatment of Barrett esophagus; to discuss the importance of dysplasia and the role of endoscopic eradication therapy for its treatment; and to review current management guidelines. Evidence Review MEDLINE and the Cochrane Library were searched from 1984 to April 2013. Additional citations were obtained by reviewing references from selected research and review articles. Findings Risk factors for cancer in Barrett esophagus include chronic GERD, hiatal hernia, advanced age, male sex, white race, cigarette smoking, and obesity with an intra-abdominal body fat distribution. The annual risk of esophageal cancer is approximately 0.25% for patients without dysplasia and 6% for patients with high-grade dysplasia. High-quality studies have found no significant differences in cancer incidence for patients with Barrett esophagus whose GERD is treated medically or surgically. Endoscopic eradication therapy with radiofrequency ablation significantly reduces the frequency of progression to cancer for patients with high-grade dysplasia. Conclusions and Relevance Endoscopic screening is recommended for patients with multiple risk factors for cancer in Barrett esophagus. For patients with Barrett esophagus without dysplasia, endoscopic surveillance at intervals of 3 to 5 years is recommended, and GERD is treated much as it is for patients without Barrett esophagus. Endoscopic eradication therapy is the treatment of choice for high-grade dysplasia and is an option for low-grade dysplasia. Endoscopic eradication therapy is not recommended for the general population of patients with nondysplastic Barrett esophagus.