cssi/SciSciGPT-SciSciNet huggingface dataset:
Multiple modes in the vibration of cantilevered shells

Abstract The term multiple modes describes pairs of modes which are similar in shape but occur at different frequencies. This phenomenon has been observed in holographic vibration test results for a turbine blade. Pairs of modes were found, such as two modes which both resembled first torsional modes. In this investigation holographic interferometry was used to verify the earlier results for the turbine blade and to investigate three shell segments simulating blades. The shells ranged in size from moderately to very thick with length to thickness ratios of 16, 8 and 5·6. The blade geometry is characterized by a circumferential angle of 142° and a ratio of length to inner radii arc length near 1·0. In addition, a NASTRAN finite element analysis was performed on these simulated blades. Both mode shapes and frequencies were found to be in good agreement with the results from the experiment. The multiple mode phenomenon was found to be an artifact of the holographic experiment. Pairs of modes were found in the NASTRAN results for the simulated blades in which the out-of-plane displacements (those seen in the hologram) were very similar, but for which the displacements in the plane of the hologram differed significantly. Thus, the two modes which appeared in the experimental results as first torsional modes were seen to include quite different in-plane displacements. The two modes are therefore quite different and do not contradict the normal result, which may be justified from such elementary considerations as a Rayleigh quotient, that similar modes must produce similar frequencies.
Carboxymethylation of sulphydryl groups in proteolipids.

— (1) The sulphydryl groups of brain white matter proteolipids were studied by alkylation with iodoacetic acid and iodoacetamide in an organic solvent medium. To make sterically hindered sulphydryl groups available, the reaction was also carried out in the presence of sodium dodecyl sulphate. (2) In all cases, iodoacetamide was a better alkylating agent than was iodoacetic acid. (3) Only minimal alkylation of crude white matter proteolipids was obtained in the absence of detergent; addition of sodium dodecyl sulphate increased the availablity of SH groups. (4) Purified proteolipids prepared by column chromatography were alkylated to a lesser degree than were crude proteolipids. (5) Prior reduction with mercaptoethanol resulted in the quantitative conversion of cysteine to S-carboxymethylcysteine with either alkylating agent and in both preparations. (6) The possibility of a conformational difference between the protein in the crude and purified preparations is discussed.
Immunological analysis of the proteins of Escherichia coli ribosomes.

Abstract Immunological analysis of Escherichia coli 50 s ribosomes indicates that they contain at least seven different proteins. At least two proteins of 50 s ribosomes are homologous to two proteins in 30 s ribosomes. About four or five of the proteins in 30 s ribosomes cross-react with antiserum made to pure 50 s ribosome protein.
Octahedral and tetrahedral co-ordination states of cobalt (II) in molten zinc chloride-aluminium chloride mixtures☆

Abstract Absorption spectra of Co(II) have been studied in molten mixtures of ZnCl 2 and AlCl 3 both as a function of melt composition and of temperature. The spectral changes have been interpreted in terms of an octahedral-tetrahedral equilibrium involving chloro-complexes of Co(II), analogous to those observed in earlier work on Ni(II) in mixtures of KCl and ZnCl 2 .
The Impact of the Leadership in Energy and Environmental Design Accredited Professional (LEED-AP) Credential on Prime/General Contractor Employees

LEED accreditation is quickly becoming one of the most popular professional designations available to members of the building design and construction community. The purpose of this research was to determine the impact the LEED-AP designation has had on Prime/General Contractor employees versus employees of Owners, Architecture/Engineer firms, Subcontractors, and other organization types. Researchers created a 35-question instrument titled the Perceptions of LEED-AP Survey and e-mailed it to a total of 46,332 LEED-APs. Upon closing, 9,060 (22%) responded. A one-way analysis of variance was utilized to determine whether significant differences existed between mean responses of LEED-APs working for Prime/General Contractors and LEED-APs working for all other organization classifications. Results indicated that LEED-APs working for Prime/General Contractors felt stronger than LEED-APs working for other organization classifications that the credential has increased their salary, opportunities for promotion, an...
The quantum Hall effect: Role of inversion layer geometry

Abstract The quantum Hall effect has attracted much interest because of its potential for providing a quantum standard of resistance and an improved value of the fine structure constant. As a step toward understanding the experimental and fundamental limitations of the effect, we present a calculation of end effect errors for MOSFET devices within a simple model of an inversion layer.
Abstract: Networking Research Activities at Fermilab for Big Data Analysis

Exascale science translates to big data. In the case of the Large Hadron Collider (LHC), the data is not only immense, it is also globally distributed. Fermilab is host to the LHC Compact Muon Solenoid (CMS) experiment's US Tier-1 Center. It must deal with both scaling and wide-area distribution challenges in processing its CMS data. This poster will describe the ongoing network-related R&D activities at Fermilab as a mosaic of efforts that combine to facilitate big data processing and movement.
An Exploratory Study of the Use of Two Response Keyboards as a Means of Communication for the Severely Handicapped Child

A technique for developing communication skills for the severely handicapped child was devised. Two instruments are described along with preliminary findings regarding their use.
Dynamic infrared scene projection technology

This paper provides an overview of the critical IR projector requirements and specifications for hardware-in-the-loop (HWIL) simulations of imaging IR systems and reviews the most prominent technologies associated with IR scene projection. Each method is briefly discussed in terms of physical operation with all revelant advantages and disadvantages highlighted. A comparison of the different categories of projection devices for applicability to HWIL simulation is provided.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A comparison of bismuth- and antimony-containing transition metal cluster complexes

In recent years a number of transition metal clusters which incorporate bismuth and antimony have been reported. The structures and reaction chemistry of these complexes are compared.
A test procedure for characterizing the toughening of brittle intermetallics by ductile reinforcements

Abstract A cylindrical test specimen for evaluating the toughening of brittle intermetallics by ductile reinforcements has been evaluated. A processing procedure capable of producing specimens has been devised, using HIPing, and a method for the tensile testing of the specimen has been established. Results are presented for γ-TiAl reinforced with Nb and a Ti-33 at.% Nb alloy. The toughening imparted by these materials is interpreted in terms of their strength, ductility and interface reactions, as well as loss of constraint mediated by the extent of debonding along the reaction product layers. Finally, the results are compared with those previously obtained on actual composites.
Distribution of galanin-immunoreactive cells within sexually dimorphic components of the medial preoptic area of the male and female rat.

Abstract A high percentage of galanin-immunoreactive (GAL-I) cells within sexually dimorphic components of the medial preoptic area (MPOA) of the rat also concentrate estrogen and GAL microinjected within the medial preoptic nucleus (MPN) facilitates masculine sexual behavior after testosterone priming. Thus, we determined the distribution of GAL-I cells within the MPOA and their response to gonadal steroids. We report significantly greater numbers of GAL-I cells within the central division of the medial preoptic nucleus (MPNc) and fewer within the anteroventral periventricular nucleus (AVPv), of the gonadectomized male than the gonadectomized female; that GAL-I cell numbers and densities within the AVPv are increased significantly in the intact, testosterone- or estrogen-treated male compared to the gonadectomized male and that GAL-I cell numbers and densities within the MPNc and GAL-I cell densities within the medial division of the MPN (MPNm), are increased significantly by gonadal steroids in rats of both sexez. The results suggest an involvement of galaninergic cells within the MPOA in the regulation of sexually dimorphic, gonadal steroid-sensitive functions.
Horns on diffusion paths in multiphase diffusion couples

Abstract The formation of “horns” on diffusion paths in two-phase diffusion couples having a common matrix phase is analyzed by considering the one-dimensional form of the diffusion equation. It is shown that horns occur when flux versus distance profiles have a finite slope at the initial diffusion couple interface. In particular, the equations predict that only single horns will form, even though double horns have been reported in the literature. A model ternary system is used as an example. The model system illustrates that when the effective diffusivity is constant, the diffusion path follows a linear zigzag course and has no horns. Also, the flux profiles are symmetric with a peak at the initial interface. However, when the effective diffusivity is modeled to vary with composition, the peak shifts away from the initial interface and the flux profile has a finite slope at the origin. The result is a diffusion path with a single horn, in agreement with theory.
Expression analysis of defense-related genes in wheat in response to infection by Fusarium graminearumContribution from Purdue University Agricultural Research Programs as journal article No. 2007-18090.

Fusarium head blight (FHB), caused by the fungi Fusarium graminearum and Fusarium culmorum, is a worldwide disease of wheat (Triticum aestivum L.). The Chinese cultivar Ning 7840 is one of a few wheat cultivars with resistance to FHB. GeneCalling™, an open-architecture mRNA-profiling technology, was used to identify differentially expressed genes induced or suppressed in spikes of Ning 7840 after infection by F. graminearum. One hundred and twenty-five cDNA fragments representing transcripts differentially expressed in wheat spikes were identified. Based on BLASTN and BLASTX analyses, putative functions were assigned to some of the genes: 28 were assigned functions in primary metabolism and photosynthesis, 7 were involved in defense response, 14 were involved in gene expression and regulation, 24 encoded proteins associated with structure and protein synthesis, 42 lacked homology to sequences in the database, and 3 were similar to cloned multidrug resistance or disease resistance proteins. Of particular i...
Evaluation of biweekly pesticide applications of new insecticides for tobacco budworm (Heliothis virescens (Fabricius)) management in tobacco (Nicotiana tabacum L.) seed production

Abstract Field studies were conducted in 2010 and 2011 in North Carolina tobacco grown to produce seed to assess the longevity and efficacy of the insecticide active ingredients chlorantraniliprole and flubendiamide on Heliothis virescens (Fabricius), the most significant pest of tobacco grown for seed. Results suggest that incorporating these materials into an integrated pest management program for lepidopterous pests in seed tobacco could potentially decrease the number of insecticide applications with limited impact on natural enemies. Soil applications of chlorantraniliprole may potentially delay H. virescens infestations, further decreasing foliar insecticide applications, but activity of soil applications was not consistent between sites and years.
Projection and deflation method for partial pole assignment in linear state feedback

Two projection methods are proposed for partial pole placement in linear control systems. These methods are of interest when the system is very large and only a few of its poles must be assigned. The first method is based on computing an orthonormal basis of the left invariant subspace associated with the eigenvalues to be assigned and then solving a small inverse eigenvalue problem resulting from projecting the initial problem into that subspace. The second method can be regarded as a variant of the Weilandt deflation technique used in eigenvalue methods. >
Pain and Fatigue in Persons With Postpolio Syndrome: Independent Effects on Functioning

Abstract Jensen MP, Alschuler KN, Smith AE, Verrall AM, Goetz MC, Molton IR. Pain and fatigue in persons with postpolio syndrome: independent effects on functioning. Objectives To better understand the importance of pain and fatigue in relation to functioning, and to investigate the role that age plays in these relationships in individuals with postpolio syndrome (PPS). Design Cross-sectional survey. Setting Community-based survey. Participants Convenience sample of 446 individuals with PPS. Interventions Not applicable. Main Outcome Measures Physical functioning (Patient Reported Outcomes Measurement Information System Physical Functioning item bank items), psychological functioning (Patient Health Questionnaire-9), pain intensity (0–10 numerical rating scale [NRS]), and fatigue (0–10 NRS). Results Pain and fatigue make independent contributions to the prediction of physical and psychological functioning. Depression was more severe in the middle-aged (≤64y) group than in the young-old (65–74y) or middle-old to oldest (≥75y) groups, although the associations between pain and fatigue and both physical and psychological functioning are similar across all age cohorts. Conclusions Complaints of pain or fatigue in patients with PPS who are older or elderly should not be attributed "merely" to the process of aging. The findings also support the need for clinical trials to develop and evaluate interventions that may help patients with PPS function better by treating pain and fatigue, as well as the negative effects that these symptoms can have on functioning.
The in vitro effect on arterial wall function of serum from patients with pregnancy-induced hypertension

The object of this study was to develop an in vitro model to identify the serum factor(s) responsible for the vascular changes that occur in pregnancy-induced hypertension (preeclampsia). Segments of rabbit carotid artery were perfused for 3 hours with nutrient medium to which serum from normal pregnant women or patients with preeclampsia was added. After perfusion, ring segments of the vessels were cut and mounted in muscle chambers for force measurement. Sensitivity of the vessels to constrictor agents and endothelium-mediated relaxation was studied. The results indicate that arteries exposed to serum from preeclamptic patients developed a 2.9-fold increase in sensitivity to angiotensin II, 1.6-fold increased sensitivity to norepinephrine, and no change of sensitivity to serotonin. These effects were not accompanied by changes in isometric force. Endothelium-mediated relaxation was not affected by serum from preeclamptic patients. These findings confirm clinical observations of increased angiotensin II sensitivity in preeclampsia. The system used may facilitate identification of factors that cause the difference between the sera of normal pregnant women and those with preeclampsia.
Neotenic Phenotype and Sex Ratios Provide Insight into Developmental Pathways in Reticulitermes flavipes (Isoptera: Rhinotermitidae)

Several thousand Reticulitermes flavipes (Kollar) including worker, nymph, soldier, neotenic and alate castes were collected from three pine logs brought into the laboratory on dates five years apart. The neotenics, all nymphoid, were divided into three groups based on the extent of cuticle pigmentation and termed regular neotenics (RN), black-headed neotenics (BHN) or black neotenics (BN). All castes, from Log A, in 2008, provided a neutral sex ratio except BHN (N = 378) and BN (N = 51) which were exclusively male while the soldiers (N = 466) were female-biased. This information suggests that there is a sex-linked bifurcation along the path for termite development with a male-biased neotenic or female-biased soldier as the choice. In contrast, termites collected in 2004 from Log B provided sex ratios that included a female biased RN (N = 1017), a neutral soldier (N = 258) and male biased BHN (N = 99) and workers (N = 54). Log C, collected in 2009, provided female biased soldiers (N = 32), RNs (N = 18) and BHNs (N = 4) and only male BN (N = 5). Eight laboratory cultures, ranging in age from five to 14 years old, also were sampled and all castes sexed. The census included a 14-year old queen-right colony, an 8-year old polyandrous colony and six colonies provided nymphs and male-biased worker populations. Together these data indicate a flexible caste determination system providing a unique opportunity for a better understanding of the flexible developmental options available in R. flavipes that we discuss relative to the literature on Reticulitermes ontogeny.
VALUE OF THE xi PARAMETER IN K/sub l3/ DECAY FROM THE PION-GAUGE CONDITION.

It is shown with the help of the pion-gauge condition that the divergence of the most general boson current in ${K}_{l3}$ decay vanishes in the limit of zero four-momentum of the pion. This in turn implies $\ensuremath{\xi}=\ensuremath{-}1$ at the (unphysical) point $t=m_{K}^{}{}_{}{}^{2}$. Inasmuch as $\ensuremath{\xi}$ does not seem, experimentally, to vary much with $t$, the result is significant in the physical region and agrees with experiment.
Bioaccumulation of14 C-hexachlorobenzene in eggs and fry of Japanese medaka (Oryzias latipes)

Hexachlorobenzene (HCB) is a widespread pollutant that is persistent once it enters the ecosphere. It bioaccumulates in both terrestrial and aquatic animals and is not readily metabolized. Although HCB bioaccumulation in fresh water fish has been reported, few data are available on bioaccumulation of this or other chemicals during early developmental stages of fish. The authors used the Japanese medaka (Oryzias latipes) to examine the rates of HCB bioaccumulation during early life stages subjected to both short term (24 h) and long term (14 day) aqueous exposure. The relatively rapid development and ease of laboratory maintenance made the medaka an ideal organism for this purpose.
Redressing the balance—involving children in family therapy

This paper argues that family therapists have tended to ignore the problem of how to engage children in family therapy, and it presents a number of techniques specifically aimed at involving children in therapy. The socio-historical context of childhood is discussed and its implications for therapists examined. A number of visual techniques are then described, illustrated by case examples. These serve the function of addressing the whole family system on a number of levels and involving children fully in the process of therapy.
African American youth in the new millennium: an overview.

Abstract African American youth today are facing a fast changing world of high technology and diminishing opportunities. This generation brings a new attitude and a challenging perspective to service providers and policy makers. The policies and interventions of the past may need an upgrade to meet the needs of this new generation. The issues of poverty and meaningful opportunities are important to this generation that opposes many mainstream philosophies.
Identification and Characterization of Transmembrane Segments

Membrane proteins comprise 30-40% of all known proteins; however, they remain the most uncharacterized. The protein data bank contains very few detailed 3D structures of the transmembrane segments of transmembrane proteins. This project seeks to determine which amino acids are necessary or present in the transmembrane segment as well as the juxtamembrane segments. It also seeks to better characterize the physical orientation of the fibroblast growth factor receptor transmembrane segment in the membrane and how the amino acids are oriented within the helix. An exclusive database of transmembrane proteins and juxtamembrane domains was created to search for trends, homology, and potential phosphorylation sites. Even though only a very limited amount of homology was found, the transmembrane segment from the fibroblast growth factor receptor will be used as a model and synthesized and characterized through a variety of biophysical techniques such as multidimensional NMR spectroscopy, circular dichroism, and fluorescence spectroscopy.
A Predictive Scale for Evaluating Cyclin-dependent Kinase Substrates A COMPARISON OF p34cdc2 AND p33cdk2

Protein phosphorylation by members of the Cdk (cyclin-dependent kinase) family of protein kinases is necessary for progression through the cell cycle. However, the primary sequence determinants of Cdk substrate specificity have yet to be examined quantitatively. We have used a panel of glutathione S-transferase peptide fusions to investigate the fine-structure specificity of p33(cdk2) and p34(cdc2). Our data indicate that the generally held consensus sequences for p34(cdc2) represent a significant oversimplification of its true specificity and that this specificity is conserved between species. p33(cdk2) and p34(cdc2) have similar but distinct substrate specificities that are affected modestly by the associated cyclin subunit. We derive specific values of phosphorylation efficiencies by these enzymes that can be used to estimate the phosphorylation potential of proposed Cdk substrates.
Cardiac levels of NOS1AP RNA from right ventricular tissue recovered during lead extraction

Background There is a scarcity of cardiac tissue available for research. Objective (1) To investigate the feasibility of obtaining myocardial tissue from extracted pacemaker and defibrillator leads for gene expression analysis and (2) to examine the nitric oxide 1 adaptor protein (NOS1AP) RNA expression as a function of patient genotype. Methods Seventeen patients (age = 56 ± 20 years; 12 men; 5 pacemakers; 12 defibrillators) undergoing lead extractions for standard indications (5 device erosion; 1 vascular occlusion; 11 lead malfunction or recall) were genotyped for 2 NOS1AP single nucleotide polymorphisms—rs10494366 (T to G) and rs10918594 (C to G)—and had RNA levels measured by real-time polymerase chain reaction for collagen I, troponin I, Ca v 1.2, Kv4.3, HERG, KvLQT1, connexin 43, NOS1AP, and sodium–calcium exchanger. Ventricular tissue obtained from 3 failing hearts at transplantation served as reference. Results A high ratio of cardiac troponin I/collagen I RNA identified 9 of the 17 patient samples (muscle rich), in which the gene expression profile was similar to that of the reference ventricular samples and significantly different ( P P Conclusions Performing gene expression analyses on right ventricular tissue samples extracted with pacemaker and defibrillator leads is feasible. A significant number of samples contain cardiomyocytes that express troponin I and ion channels at levels comparable to those seen in explanted hearts. Decreased NOS1AP expression in rs10494366 TT and rs10918594 CC homozygotes may underlie shorter repolarization times.
College football game day stadium incidents: policy and environmental effects on alcohol-related ejections and crime

Alcohol-related crime and misconduct remain an ongoing problem at university-sponsored sporting events in the USA. Prior research has focused on the impact of alcohol on spectator behavior at sporting events, but has not linked policy and environmental factors to behavior inside venues. This study seeks to explore the connection between policy and environmental variables' impact and reported alcohol-related crime and ejection rates within college football stadiums. The analysis tested the effect of alcohol sales policy (sales allowed or prohibited), law enforcement ejection policy, temperature, time of game, whether the home team is ranked, whether the visitor team is ranked, conference game, in-state rivalry, and attendance on college football games in seven stadiums in the USA over the course of three years. Attendance, followed by alcohol sales policy and start time of game, had a direct relationship on and influenced an increase in crime. Law enforcement policy on reporting ejections, followed by temp...
Broadband microlithography: process development using PROLITH simulator

It was demonstrated that optical lithography simulations can be used very effectively for broadband application and they are not the forte of I-line lithography. PROLITH simulator was used to optimize the photo process on Ultratech 1500 broadband stepper. More than 40 process variables were required to customize the software for this process. To do a broadband simulation the optical parameters of photoresist should be measured accurately on multiple wavelengths. This information not always available from photoresist vendors and often tedious to obtain by means of UV spectroscopy. To do the final tune up the resist exposure rate C was scaled by the same factor N within the entire illumination range of 380-450 nm to match the experimental Dose-to-clear value E. Good agreement with experimental data was achieved on different device layers. Process window for the critical geometry was calculated based on the linewidth and sidewall angle specifications. Better understanding of the process allowed us to qualify new process into production in very short time frame and saved a lot of test wafers. Further process optimization is under way and efforts are being made to identify the optimum process for the future devices with smaller CDs.
Successful integration of informal learning in engineering education

Research suggests that an emerging environment of ubiquitous information technology affords seamless movement between formal learning, informal learning, and the workplace. This paper reviews research data from one successful teaching and learning methodology that leverages seamless movements between informal and formal learning in engineering education. The research is an ongoing pilot study at the University of Hartford using data from selected technical mathematics and communication electronics courses. The research data suggests that clearly defined academic jurisdictions have a positive correlation with successful integration of formal learning, informal learning, and the workplace. However, themes from the data also suggest that crossing academic boundaries involves more than technology issues and could raise the specter of unintended social-dramas. One theme suggests that, in a seamless environment without clearly defined academic jurisdictions, opportunities for collaboration could be misinterpreted as encroachments. To mitigate issues of competing jurisdictional interests this study employs Learner Agent Objects (LAO) individual portfolios. LAO portfolios are collections of evidence-based artifacts representing a learner's academic experience that independently moves with the learner as data network nodes between jurisdictions in engineering education and the workplace.
An automatic method for enhancing the display of different tissue densities in digital chest radiographs

Digital chest radiographs are often too bright and/or lack contrast when viewed on a video display. This often occurs in radiographs taken of patients with dense lungs, or when incorrect x-ray exposure techniques or inappropriate image preprocessing operations are performed (eg, by the computed radiography system or laser scanner). This article describes a method to automatically provide brightness and contrast adjustments to selectively enhance either soft or dense tissues. This method reduces viewer interaction and improves displayed image quality. The algorithm analyzes the gray-level histogram of a chest radiograph and determines the breakpoints that separate the region outside the patient (background), the radiographically soft tissues, and the radiographically dense tissues. From these breakpoints, a series of piecewise linear look-up tables (LUTs) is generated to selectively enhance either the soft tissues or the dense tissues. This is performed by: (1) varying the contrast in the patient background to achieve the desired overall brightness, (2) selectively increasing the contrast of the tissue region of interest, and (3) reducing or maintaining the contrast of the remaining region. The resulting LUTs are applied to the original image via video display.
Evolution inclusions for time dependent families of subgradients

This paper presents easy to check conditions for the existence and uniqueness of strong solutions to evolution inclusions in a Hilbert space involving a time dependent family of subgradients which are of the form The conditions for existence and uniqueness of a solution involve an assumption of Lipshitz continuity of the convex functions rather than a Lipschitz condition on the resolvents. No smoothness is assumed on the function, f.
Nonhuman primate embryonic stem cells as a preclinical model for hematopoietic and vascular repair

Stem cell-based regenerative medicine therapies have been touted recently as a novel therapeutic approach to treat and cure a wide range of diseases. Both adult and embryonic stem (ES) cells can serve as important sources of precursor cells to derive more mature cells potentially utilized for clinical applications. Nonhuman primates have proven useful as a preclinical model, as demonstrated in studies of hematopoietic cell transplantation, gene therapy, and other areas. The derivation of nonhuman primate ES cells now provides an optimal resource to characterize and test ES cell-based therapies prior to trials with human ES cells. This review describes work to define strategies and mechanisms to derive blood and endothelial cells from nonhuman primate ES cells isolated from various species. Preclinical testing that solely relies on studies of putative therapeutic cells derived from mouse ES cells transplanted into other mice, or analyses of human ES cell-derived cells transplanted into immunodeficient or immunosuppressed rodents may not be predictive of efficacy in subsequent human trials. However, future testing using nonhuman primate ES cell-derived therapeutic cells done as an allogeneic transplant may best predict success for subsequent studies using human ES cells. Therefore, additional research on nonhuman primate ES cells, in addition to work on mouse and human ES cells, is greatly needed to facilitate clinical translation of new stem cell treatments.
Escape from Prisoner’s Dilemma in RNA Phage Φ6

Abstract: We previously examined competitive interactions among viruses by allowing the RNA phage Φ6 to evolve at high and low multiplicities of infection (ratio of infecting viruses to bacterial cells). Derived high‐multiplicity phages were competitively advantaged relative to their ancestors during coinfection, but their fixation caused population fitness to decline. These data conform to the evolution of lowered fitness in a population of defectors, as expected from the Prisoner’s Dilemma of game theory. However, the generality of this result is unknown; the evolution of viruses at other multiplicities may alter the fitness payoffs associated with conflicting strategies of cooperation and defection. Here we examine the change in matrix variables by propagating the ancestor under strictly clonal conditions, allowing cooperation the chance to evolve. In competitions involving derived cooperators and their selfish counterparts, our data reveal a new outcome where the two strategies are predicted to coexis...
Automating the expert consensus paradigm for robust lung tissue classification

Clinicians confirm the efficacy of dynamic multidisciplinary interactions in diagnosing Lung disease/wellness from CT scans. However, routine clinical practice cannot readily accomodate such interactions. Current schemes for automating lung tissue classification are based on a single elusive disease differentiating metric; this undermines their reliability in routine diagnosis. We propose a computational workflow that uses a collection (#: 15) of probability density functions (pdf)-based similarity metrics to automatically cluster pattern-specific (#patterns: 5) volumes of interest (#VOI: 976) extracted from the lung CT scans of 14 patients. The resultant clusters are refined for intra-partition compactness and subsequently aggregated into a super cluster using a cluster ensemble technique. The super clusters were validated against the consensus agreement of four clinical experts. The aggregations correlated strongly with expert consensus. By effectively mimicking the expertise of physicians, the proposed workflow could make automation of lung tissue classification a clinical reality.
Broadband localization in a dispersive medium through sparse wavenumber analysis

Matched field processing is a powerful tool for accurately localizing targets in dispersive media. However, matched field processing requires a precise model of the medium under test. In underwater acoustics, where matched field processing has been extensively studied, authors often resort to extremely detailed numerical models of the propagation medium, which are computationally expensive and impractical for many applications. As an alternative, this paper uses convex sparse recovery techniques to construct, directly from measured data, an accurate model of a plate medium based on its dispersion characteristics. From this data-driven model, the Green's function between two points can be readily predicted. We demonstrate the effectiveness of this model by localizing a source in a dispersive plate medium. The results visually illustrate our approach to significantly improve localization accuracy and reduce artifacts when compared to a conventional narrowband technique.
Geometric representation of cubic graphs with four directions

We show that every connected cubic graph can be drawn in the plane with straight-line edges using only four distinct slopes and disconnected cubic graphs with five distinct slopes.
Dopamine transporter gene variation modulates activation of striatum in youth with ADHD

Polymorphisms in the 3'UTR variable number tandem repeat (VNTR) of exon 15 of the dopamine transporter gene (DAT1) have been linked to attention-deficit hyperactivity disorder (ADHD); moreover, variability in DAT1 3'UTR genotype may contribute to both heterogeneity of the ADHD phenotype and differences in response to stimulant medications. The impact of this VNTR on neuronal function in individuals with ADHD remains unclear despite evidence that the polymorphisms influence dopamine transporter expression. Thus, we used event-related functional magnetic resonance imaging to examine the impact of DAT1 3'UTR genotype on brain activation during response inhibition in unmedicated children and adolescents with ADHD. Twenty-one youth with ADHD who were homozygous for the 10-repeat (10R) allele of the DAT1 3'UTR and 12 youth who were carriers of the 9-repeat (9R) allele were scanned while they performed a Go/No-Go task. Response inhibition was modeled by contrasting activation during correct No-Go trials versus correct Go trials. Participants who were homozygous for the DAT1 3'UTR 10R allele and those who had a single 9R allele did not differ on percent of trials with successful inhibition, which was the primary measure of inhibitory control. Yet, youth with the DAT1 3'UTR 10R/10R genotype had significantly greater inhibitory control-related activation than those with one 9R allele in the left striatum, right dorsal premotor cortex, and bilaterally in the temporoparietal cortical junction. These findings provide preliminary evidence that neural activity related to inhibitory control may differ as a function of DAT1 3'UTR genotype in youth with ADHD.
Potential energy functions: From consistent force fields to spectroscopically determined polarizable force fields

We review our methodology for producing physically accurate potential energy func- tions, particularly relevant in the context of Lifson's goal of including frequency agreement as one of the criteria of a self-consistent force field. Our spectroscopically determined force field (SDFF) procedure guarantees such agreement by imposing it as an initial constraint on parameter optimization, and accomplishes this by an analytical transformation of ab initio "data" into the energy function format. After describing the elements of the SDFF protocol, we indicate its implementation to date and then discuss recent advances in our representation of the force field, in particular those required to produce an SDFF for the peptide group. © 2003 Wiley Periodicals, Inc. Biopolymers 68: 383-394, 2003
Gathering knowledge for a question answering system from heterogeneous information sources

Although vast amounts of information are available electronically today, no effective information access mechanism exists to provide humans with convenient information access. A general, open-domain question answering system is a solution to this problem. We propose an architecture for a collaborative question answering system that contains four primary components: an annotations system for storing knowledge, a ternary expression representation of language, a transformational rule system for handling some complexities of language, and a collaborative mechanism by which ordinary users can contribute new knowledge by teaching the system new information. We have developed a initial prototype, called Webnotator, with which to test these ideas.
Irrigation-Induced Rainfall and the Great Plains

The post‐World War II increase in irrigation in the Great Plains represents the largest human-induced hydrologic impact in North America. Drawn primarily from the High Plains aquifer, water applied as irrigation in the region amounts to billions of cubic meters (2 3 1010 m3 in 1990) annually and is applied to more than 60 000 km2 of farmland. Following studies by Schickedanz and by Barnston and Schickedanz, empirical orthogonal functions and precipitation magnitude comparisons were employed to examine trends in precipitation over the region and to determine if this enormous addition of irrigation water to the surface has had a measurable influence on precipitation during the summer months of June, July, and August. The Barnston and Schickedanz study observed a transition from unirrigated to heavily irrigated conditions; in contrast, this examination focused on a more recent period during which irrigation took place throughout the time of interest. Loading patterns and temporal precipitation trends for 1950‐97 show, at best, slight evidence that irrigation induces rainfall. The most prominent evidence of an irrigation effect is found in the Texas Panhandle for 1950‐82. If irrigation-induced rainfall exists, its impact is only minor relative to the natural determining factors of plains climate. It also is possible that the chief influence of irrigation on rainfall may take place at some threshold magnitude of irrigation (not explored in this study) that already had been exceeded by 1950.
Friendship: Bonds and Binds in a Voluntary Relationship

This paper develops an approach to the understanding of cultural problems in the friendship bond. Utilizing depth interview field data from respondents of both sexes aged eighteen to eighty, plus self-reports of friendship problems by college students and applicable theories of relationship behaviour, two important aspects of friendship culture are probed: (1) the desirable personality traits of friends and the expectation that these will not change; (2) the assumption of an unwritten contract between friends concerning the provision of aid and the repayment of kindnesses. The two major characteristics of the friendship bond that make it both unique in human group life and attractive - freedom and intimacy - also set in motion an internal dialectic which can be the basis of problems between friends or the eventual demise of the relationship. The voluntary aspect of friendship means that it has little of the societal support that other relationships enjoy and that behaviour between friends is freely select...
Analytical Separations of Schiff Base Chelates by Reverse Phase Hplc on a 10 Micron C-18 Bonded Silica Subtrate

Abstract Reverse phase partition chromatography on a 10 micron silica-bonded octadecyl hydrocarbon substrate is applied to the separation of neutral tetradentate chelates of copper (II), nickel (II) and palladium (II) with a range of non-fluorinated and fluorinated beta-ketoamine and salicylaldimine ligands. Variation of retention and resolution with respect to changes in ligand structure and metal chelated is investigated using acetonitrile, methanol and water solvent systems. Detection limits (254 nm) and linearity ranges of response are indicated.
Effect of temperature and mass transport on transition metal isotope fractionation during electroplating

Transition metal stable isotope signatures can be useful for tracing both natural and anthropogenic signals in the environment, but only if the mechanisms responsible for fractionation are understood. To investigate isotope fractionations due to electrochemistry (or redox processes), we examine the stable isotope behavior of iron and zinc during the reduction reaction M^(2+)_(aqueous) + 2e^− = M_(metal) as a function of electrochemical driving force, temperature, and time. In all cases light isotopes are preferentially electroplated, following a mass-dependent law. Generally, the extent of fractionation is larger for higher temperatures and lower driving forces, and is roughly insensitive to amount of charge delivered. The maximum fractionations are δ^(56/54)Fe = −4.0‰ and δ^(66/64)Zn = −5.5‰, larger than observed fractionations in the natural environment and larger than those predicted due to changes in speciation. All the observed fractionation trends are interpreted in terms of three distinct processes that occur during an electrochemical reaction: mass transport to the electrode, chemical speciation changes adjacent to the electrode, and electron transfer at the electrode. We show that a large isotope effect adjacent the electrode surface arises from the charge-transfer kinetics, but this effect is attenuated in cases where diffusion of ions to the electrode surface becomes the rate-limiting step. Thus while a general increase in fractionation is observed with increasing temperature, this appears to be a result of thermally enhanced mass transport to the reacting interface rather than an isotope effect associated with the charge-transfer kinetics. This study demonstrates that laboratory experiments can successfully distinguish isotopic signatures arising from mass transport, chemical speciation, and electron transfer. Understanding how these processes fractionate metal isotopes under laboratory conditions is the first step towards discovering what role these processes play in fractionating metal isotopes in natural systems.
Strategic Human Resource Management of Volunteers and the Link to Hospital Patient Satisfaction

This article uses strategic human resource management theory to consider the ways in which volunteers can potentially enhance hospital patient satisfaction. Results of a structural equation modeling analysis of multi-source data on 107 U.S. hospitals show positive associations between hospital strategy, volunteer management practices, volunteer workforce attributes, and patient satisfaction. Although no causality can be assumed, the results shed light on the volunteer–patient satisfaction relationship and have important implications for hospital leaders, volunteer administrators, and future research.
Genetics of the insulin receptor defect in a patient with extreme insulin resistance.

A patient with extreme insulin resistance (leprechaun/Ark-1) had an 80–90% decrease in the number of insulin receptors on her circulating monocytes. In contrast, while a normal number of insulin receptors was expressed on the surface of Epstein-Barr (EB) virus-transformed lymphocytes from the patient, the receptors had decreased sensitivity to changes in temperature and pH. The father, who had a moderate degree of insulin resistance, resembled the patient in that his monocytes had a 60–80% decrease in the number of insulin receptors. Binding to the father's EB virus-transformed lymphocytes was normal. The mother was normally sensitive to insulin and had a normal number of insulin receptors on her circulating monocytes. In contrast, insulin receptors on the mother's EB virustransformed lymphocytes were qualitatively abnormal, closely resembling the daughter's cultured cells. These observations suggest that each parent has transmitted a different genetic defect to the patient. When both mutations coexist in...
Mitigating Supply Risk: Dual Sourcing or Process Improvement?

Surveys suggest that supply chain risk is a growing issue for executives and that supplier reliability is of particular concern. A common mitigation strategy is for the buying firm to expend effort improving the reliability of its supply base. We explore a model in which a firm can source from multiple suppliers and/or exert effort to improve supplier reliability. For both random capacity and random yield types of supply uncertainty, we propose a model of process improvement in which improvement efforts (if successful) increase supplier reliability in the sense that the delivered quantity (for any given order quantity) is stochastically larger after improvement. We characterize the optimal procurement quantities and improvement efforts and generate managerial insights. For random capacity, improvement is increasingly favored over dual sourcing as the supplier cost heterogeneity increases, but dual sourcing is favored over improvement if the supplier reliability heterogeneity is high. In the random yield model, increasing cost heterogeneity can reduce the attractiveness of improvement, and improvement can be favored over dual sourcing if the reliability heterogeneity is high. A combined strategy (improvement and dual sourcing) can provide significant value if suppliers are very unreliable and/or capacity is low relative to demand.
Multi-task Reinforcement Learning in Partially Observable Stochastic Environments

We consider the problem of multi-task reinforcement learning (MTRL) in multiple partially observable stochastic environments. We introduce the regionalized policy representation (RPR) to characterize the agent's behavior in each environment. The RPR is a parametric model of the conditional distribution over current actions given the history of past actions and observations; the agent's choice of actions is directly based on this conditional distribution, without an intervening model to characterize the environment itself. We propose off-policy batch algorithms to learn the parameters of the RPRs, using episodic data collected when following a behavior policy, and show their linkage to policy iteration. We employ the Dirichlet process as a nonparametric prior over the RPRs across multiple environments. The intrinsic clustering property of the Dirichlet process imposes sharing of episodes among similar environments, which effectively reduces the number of episodes required for learning a good policy in each environment, when data sharing is appropriate. The number of distinct RPRs and the associated clusters (the sharing patterns) are automatically discovered by exploiting the episodic data as well as the nonparametric nature of the Dirichlet process. We demonstrate the effectiveness of the proposed RPR as well as the RPR-based MTRL framework on various problems, including grid-world navigation and multi-aspect target classification. The experimental results show that the RPR is a competitive reinforcement learning algorithm in partially observable domains, and the MTRL consistently achieves better performance than single task reinforcement learning.