cssi/SciSciGPT-SciSciNet huggingface dataset:
Modification of polyethylene terephthalate (dacron) via denier reduction: Effects on material tensile strength, weight, and protein binding capabilities

Thrombosis remains a significant and potentially catastrophic complication of polyethylene terephthalate (Dacron) prosthetic vascular graft implantation. Numerous attempts have been made to create a novel surface that reduces the adverse effects of blood interaction with the material. The purpose of this study was to create reactive groups on Dacron without significantly altering the chemical and physical properties of the biomaterial. These groups would then serve as “anchor sites” for covalent attachment of the blood protein albumin to the surface, thus creating a more biocompatible surface. Denier reduction, an established textile chemistry procedure that creates carboxyl groups on the fiber surface via hydrolysis of the material, was performed at 100°C using sodium hydroxide concentrations of 0.5, 1.0, 2.5, and 5.0% (treated materials referred to as 0.5% hydrolyzed etc.). Tensile strength determination of hydrolyzed materials revealed no statistically significant difference in material strength between control, 0.5, and 1.0% hydrolyzed materials; the 2.5 and 5.0% hydrolyzed materials had significant strength loss as compared to the controls. Significant fiber weight loss occurred in the 1.0, 2.5, and 5.0% hydrolyzed Dacron segments. The 0.5% hydrolyzed material did not have any significant weight loss. Covalent linkage of 125I-albumin to these modified materials using the crosslinker 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide hydrochloride (EDC) resulted in the 0.5% hydrolyzed material having the greatest protein binding (330 ng/mg Dacron, 2.4-fold greater than control). Incubation of the 0.5% hydrolyzed material with EDC and various concentrations of 125I-albumin resulted in the 14.80 mM solution permitting the greatest binding per milligram Dacron (330 ng/mg Dacron). Scanning electron microscopy, performed blindly, revealed no change in the 0.5% hydrolyzed Dacron as compared to untreated Dacron. The 5.0% hydrolyzed Dacron, however, had noticeable structural damage on the outer periphery of the fiber surface. Observation of the untreated Dacron with nonspecifically bound albumin showed scattered areas of albumin adherent to the fiber surface whereas covalent linkage of albumin to the 0.5% hydrolyzed Dacron via EDC crosslinking showed numerous albumin moieties on each fiber. This study demonstrates that a clinically accepted biomaterial (Dacron) can be chemically modified, without significantly altering the physical and chemical characteristics of the biomaterial, in order to covalently bind albumin to the fiber surface. Thus, these results serve as foundation for creating potential novel biomaterials without significantly altering the properties of the original biomaterial. © 1995 John Wiley & Sons, Inc.
Distinct functional roles of homologous Cu+ efflux ATPases in Pseudomonas aeruginosa

In bacteria, most Cu(+) -ATPases confer tolerance to Cu by driving cytoplasmic metal efflux. However, many bacterial genomes contain several genes coding for these enzymes suggesting alternative roles. Pseudomonas aeruginosa has two structurally similar Cu(+) -ATPases, CopA1 and CopA2. Both proteins are essential for virulence. Expressed in response to high Cu, CopA1 maintains the cellular Cu quota and provides tolerance to this metal. CopA2 belongs to a subgroup of ATPases that are expressed in association with cytochrome oxidase subunits. Mutation of copA2 has no effect on Cu toxicity nor intracellular Cu levels; but it leads to higher H(2) O(2) sensitivity and reduced cytochrome oxidase activity. Mutation of both genes does not exacerbate the phenotypes produced by single-gene mutations. CopA1 does not complement the copA2 mutant strain and vice versa, even when promoter regions are exchanged. CopA1 but not CopA2 complements an Escherichia coli strain lacking the endogenous CopA. Nevertheless, transport assays show that both enzymes catalyse cytoplasmic Cu(+) efflux into the periplasm, albeit CopA2 at a significantly lower rate. We hypothesize that their distinct cellular functions could be based on the intrinsic differences in transport kinetic or the likely requirement of periplasmic partner Cu-chaperone proteins specific for each Cu(+) -ATPase.
Molecular Beam Epitaxy of ZnS Films on Arsenic Passivated Silicon Surfaces

The crystalline quality of ZnS films grown on arsenic covered Si(100) surfaces is shown to be improved as compared to films grown on bare silicon surfaces by MBE (molecular beam epitaxy). Employing RGA (residual gas analyzer) and RHEED (reflection high energy electron diffraction) techniques, we found that a strong initial adsorption of sulfur on bare silicon surfaces led to the formation of disordered silicon-sulfide surfaces. This disordered surface initiated three-dimensional growth of ZnS and resulted in poor crystalline quality. An arsenic overlayer was found to be effective in preventing the interaction of sulfur with the silicon surface and thereby maintained surface ordering. X-ray rocking curve analysis indicated higher crystallinity in ZnS films grown on arsenic covered surfaces.
UWB small scale channel modeling and system performance

Recently, ultra-wideband (UWB) technology based on the transmission of short duration pulses has gained much interest for its application to wireless communications. UWB small scale channel modeling work, including statistical characterization and potential models, are discussed. The significance, in terms of performance, of the channel impulse response model chosen for the simulation of UWB communications systems is also evaluated. Three traditional models are found to be useful for modeling NLOS UWB channels, but not LOS channels. A new model for LOS UWB channels is presented and shown to represent LOS channels much more accurately than the traditional models.
An Algorithm for Constructing and Searching Spaces of Alternative Hypotheses

In this paper, we develop techniques for automated hypothesis-space exploration over data sets that may contain contradictions. To do so, we make use of the equivalence between two formulations: those of first-order predicate logic with prefix modal quantifiers under the finite-model hypothesis and those of mixed-integer linear programming (MILP) problems. Unlike other approaches, we do not assume that all logical assertions are true without doubt. Instead, we look for alternative hypotheses about the validity of the claims by identifying alternative optimal solutions to a corresponding MILP. We use a collection of slack variables in the derived linear constraints to indicate the presence of contradictory data or assumptions. The objective is to minimize contradictions between data and assertions represented by the presence of nonzero slack in the set of linear constraints. In this paper, we present the following: 1) a correspondence between first-order predicate logic with modal quantifier prefixes under the finite-model hypothesis and MILP problems and 2) an implicit enumeration algorithm for exploring the contradiction hypothesis space.
Systemic Signaling in Tomato Plants for Defense against Herbivores ISOLATION AND CHARACTERIZATION OF THREE NOVEL DEFENSE-SIGNALING GLYCOPEPTIDE HORMONES CODED IN A SINGLE PRECURSOR GENE

An 18-amino acid peptide in tomato leaves called systemin is a primary signal released at wound sites in response to herbivory that systemically signals the activation of defense genes throughout the plants. We report here the isolation of three hydroxyproline-rich glycopeptides from tomato leaves, of 20, 18, and 15 amino acids in length, that signal the activation of defense genes, similar to the activity of the systemin peptide. The three new peptides cause an alkalinization of suspension-cultured cells and induce the synthesis of defensive proteinase inhibitor proteins when supplied at fmol levels to young tomato plants through their cut stems. This suggests that they are part of the wound signaling of tomato plants that activates defense against herbivores and pathogens. Isolation of cDNAs coding for the tomato peptides revealed that they are all derived from the same pre-proprotein precursor that is systemically wound-inducible. The peptides are considered members of the functionally characterized systemin family of defense signals from plants that are synthesized both in wounded leaves and in distal, unwounded leaves in response to herbivory or other mechanical wounding. The precursor deduced from the cDNA exhibits a leader sequence, indicating that it is synthesized through the secretory pathway, where it is hydroxylated and glycosylated. The amino acid sequence of the precursor exhibited weak identity to the precursor of two hydroxyproline-rich defense signals recently found in tobacco, suggesting that the two pre-protein precursors have evolved from a common ancestral protein. The identification of hydroxyproline-rich glycoprotein systemins in tomato indicates that the initiation of wound signaling is more complex than previously thought and appears to involve multiple peptide signals.
Life extension through charge equalization of lead-acid batteries

Charge equalization is an important part of the charge process for series-connected battery cells. This paper reviews battery behavior and performance related to the equalization problem, in the context of valve-regulated lead-acid batteries. As established in prior work, equalization precision on the order of 10 mV/cell is required for a successful process. Equalization processes that can achieve this precision do indeed extend the life of battery packs. Active equalization speeds the process and supports exchange of a single failed cell or monoblock Passive equalization (conventional overcharge) is too slow in most contexts for strings longer than about 12 cells. Active equalization provides clear life advantages over other approaches. The results are consistent with the hypothesis that a properly designed active equalization process can provide battery cycle life for a series string that matches the cycle operating results for an individual cell.
Fast inference and learning in large-state-space HMMs

For Hidden Markov Models (HMMs) with fully connected transition models, the three fundamental problems of evaluating the likelihood of an observation sequence, estimating an optimal state sequence for the observations, and learning the model parameters, all have quadratic time complexity in the number of states. We introduce a novel class of non-sparse Markov transition matrices called Dense-Mostly-Constant (DMC) transition matrices that allow us to derive new algorithms for solving the basic HMM problems in sub-quadratic time. We describe the DMC HMM model and algorithms and attempt to convey some intuition for their usage. Empirical results for these algorithms show dramatic speedups for all three problems. In terms of accuracy, the DMC model yields strong results and outperforms the baseline algorithms even in domains known to violate the DMC assumption.
The Atomic, Electronic and Defect Structure of the Dynamically Formed Cu2O/Cu Interfaces

To gain fundamental insights into metal oxidation, the dynamically formed Cu/Cu2O interface was investigated by cross-sectional TEM (Transmission Electron Microscopy) methods. Copper (001) films were oxidized in oxygen within a UHV chamber to create Cu2O islands that formed epitaxially with respect to the Cu film. The cross-sectional Cu2O/Cu TEM sample was prepared by dual beam (DB) focused ion beam (FIB) instrument and the interface was probed by high-resolution TEM (HREM) and electron energy loss spectrum (EELS). It is found that Cu2O {110} layer distance significantly decreases from the interface area to the bulk Cu2O region, which is about 3∼4 unit cell thickness in Cu2O side; while the {100Cu2O layer distance increases with increasing distance from the interface region. The chemical Cu/Cu2O interface thickness has been measured with EELS analysis, which is about 2nm where the oxidation state of Cu gradually changes from Cu0 to Cu+1. This transition region indicates the area where Cu/Cu2O interface exists and suggests the existence of metastable Cu oxides. The Cu2O island growth mechanism of predominantly anion interfacial diffusion at the initial stage oxidation has been proposed.
Efficiency of transduction by recombinant Sindbis replicon virus varies among cell lines, including mosquito cells and rat sensory neurons.

Recombinant alphaviruses have been used as vehicles for delivery and expression of heterologous genes in mammalian, avian and insect cell lines. We have used a Sindbis replicon virus (Sinreplac) ab...
Social Influences on Executive Functions Development in Children and Adolescents: Steps Toward a Social Neuroscience of Predictive Adaptive Responses

This commentary discusses the findings and implications of four empirical papers that establish a reciprocal, longitudinal link between the social environment and executive functions from childhood to adolescence. Two future directions are suggested by this work. The first is a call for measurement research to clarify the nomological network of various measurements of self-regulation and executive functions across a variety of methods and procedures. The second new direction is to broaden the analysis of executive function to include a wider array of predictive adaptive responses to various environmental conditions, including those where youth are chronically marginalized or otherwise stressed. Findings from these studies suggest that the executive functions within the brain guide adaptation in both deviant as well as competent responses to the social environment. Understanding various forms of adaptation will enhance the potential for prevention as well as avoid iatrogenic intervention strategies with misinformed targets.
Some Aspects of Organizational Craziness

From the time I finished graduate school in 1942 I developed a strong interest in how organizations, any organization, worked and differentially affected those who worked in them in ways that facilitated or were barriers to the realization of their purposes. My first job was in a new state institution for mentally retarded individuals; it was there that I very quickly learned about what I came to call “organizational craziness,” a craziness that shaped lives and purposes of everyone in the organization for good or for bad. The history of human service institutions is a grim one and very unpleasant reading. That history confirms the adage that the more things change the more they remain the same. Initially my interest in organizations was a matter of self-defense: I was being influenced, shaped, and pressured to think and act in ways incompatible with my beliefs and values. For the rest of my career up until a few years ago I took advantage of every opportunity, and I had many, to observe and consult to human service institutions. I learned a lot and the most important thing I learned was that organizational theorists and practitioners in the private sector were learning the same thing.
Online Instructor Perceptions of Social Presence and Educational use of Social Media

This study examined active online university instructors’ perceptions of social presence in a learning management system (LMS), use of social media tools, and willingness to use social media tools outside of an LMS to increase social presence. Data were collected via an anonymous electronic survey. Results indicated instructors perceived a high level of social presence in an LMS, but there were specific limitations. Subscription to multiple social media tools was common, but use of these tools for social communications with students or other instructors was rare. Instructors expressed a willingness to try social media tools outside an LMS to increase social presence. There is a continued and increasing demand for “virtual” education. While distance-provided curriculum, efficacy of online education delivery platforms and students’ characteristics, preferences, and learning styles are all studied, examination of the perceptions of faculty who facilitate learning in a distance format is limited. To achieve success in the cyberspace of education, understanding the behaviors and attitudes of instructors who lead the day-to-day operations of course facilitation are paramount to sustainability.
One-Dimensional Analysis of Floods and Tides in Open Channels

The one-dimensional equations of gradually varied, unsteady flow in open channels are integrated to obtain stages and discharges along a river subject to tides and floods. An explicit procedure in finite differences is used, considering branches, independent tributaries (pumps), contractions due to bridges or barriers, with or without tidal gates and flood plains restricted or not by levees. The boundary conditions may be represented by: tides at both ends; tides at one end and discharge at the other; surge or stage hydrographs at any station; and combinations of the previous conditions. Three examples are presented covering a wide range of conditions.
Syncope in a middle-aged man at work.

(1995). Syncope in a Middle-aged Man at Work. Hospital Practice: Vol. 30, No. 3, pp. 52-52.
Information Algebras and Their Applications

In this lecture we will present joint work with Ryan Thorngren on thermodynamic semirings and entropy operads, with Nicolas Tedeschi on Birkhoff factorization in thermodynamic semirings, ongoing work with Marcus Bintz on tropicalization of Feynman graph hypersurfaces and Potts model hypersurfaces, and their thermodynamic deformations, and ongoing work by the author on applications of thermodynamic semirings to models of morphology and syntax in Computational Linguistics.
Influence of Adult Meadow Spittlebug Feeding on Forage Quality

Adult meadow spittlebugs, Philaenus spumarius (L.), were placed in several densities on potted caged alfalfa, birdsfoot trefoil. and red clover plants. The effect of spittlebug feeding on quality was determined by analyzing (or protein, fat, crude fiber, ash, and nitrogen-free extract (simple sugars) Alfalfa was considerably more susceptible to damage at the infestation rates tested than either red clover or birds-foot trefoil. It was shown that heavy infestations of adult meadow spittlebugs may cause serious damage to forage legume quantity and quality. In general there was a reduction of protein, fat, and moisture content.
Family capital: Examining social capital, family commitment, and acculturation among college-enrolled Mexican-American men and women in the Southwestern United States

ABSTRACTSocial capital is integral to an individual’s ability to access various resources embedded in social and familial networks that are important in academic access and future success. The types and dynamics of social relationships created by men and women are thought to generate different forms of social capital with factors such as acculturation resulting in differences in intercultural networks and potential resource access. However, the factors that contribute to the development of social capital require further investigation. The current study examines the relationship between acculturation, family role commitment, and various social network characteristics associated with social capital among Mexican-American college-enrolled men (n = 119) and women (n = 196). Several multiple regressions were conducted. Findings indicate that acculturation and family role commitment relate differently to social-capital-network characteristics among Mexican-American men and women. For women, marital commitment w...
Metabolic Requirements of Escherichia coli in Intracellular Bacterial Communities during Urinary Tract Infection Pathogenesis

Uropathogenic Escherichia coli (UPEC) is the primary etiological agent of over 85% of community-acquired urinary tract infections (UTIs). Mouse models of infection have shown that UPEC can invade bladder epithelial cells in a type 1 pilus-dependent mechanism, avoid a TLR4-mediated exocytic process, and escape into the host cell cytoplasm. The internalized UPEC can clonally replicate into biofilm-like intracellular bacterial communities (IBCs) of thousands of bacteria while avoiding many host clearance mechanisms. Importantly, IBCs have been documented in urine from women and children suffering acute UTI. To understand this protected bacterial niche, we elucidated the transcriptional profile of bacteria within IBCs using microarrays. We delineated the upregulation within the IBC of genes involved in iron acquisition, metabolism, and transport. Interestingly, lacZ was highly upregulated, suggesting that bacteria were sensing and/or utilizing a galactoside for metabolism in the IBC. A ΔlacZ strain displayed significantly smaller IBCs than the wild-type strain and was attenuated during competitive infection with a wild-type strain. Similarly, a galK mutant resulted in smaller IBCs and attenuated infection. Further, analysis of the highly upregulated gene yeaR revealed that this gene contributes to oxidative stress resistance and type 1 pilus production. These results suggest that bacteria within the IBC are under oxidative stress and, consistent with previous reports, utilize nonglucose carbon metabolites. Better understanding of the bacterial mechanisms used for IBC development and establishment of infection may give insights into development of novel anti-virulence strategies. Importance Urinary tract infections (UTIs) are one of the most common bacterial infections, impacting mostly women. Every year, millions of UTIs occur in the U.S. with most being caused by uropathogenic E. coli(UPEC). During a UTI, UPEC invade bladder cells and form an intracellular bacterial community (IBC) that allows for the bacteria to replicate protected from the host immune response. In this study, we investigated genes that are expressed by UPEC within the IBC and determined how they contribute to the formation of this specialized community. Our findings suggest that galactose is important for UPEC growth in the IBC. Additionally, we found that a gene involved in oxidative stress is also important in the regulation of a key factor needed for UPEC invasion of bladder cells. These results may open the door for the development of treatments to diminish UTI frequency and/or severity.
Development of a Scanning Equipment for Ultrasonic Testing of Small-Diameter Tube Welds

An automatic scanning equipment for ultrasonic testing of small-diameter tube welds was developed to solve the problems of large amount of work and uninspected weld zones due to the small gaps of the tube lines of power station water-cooling system in manual ultrasonic testing. All the welds in a boiler were automatically inspected by the probe scanning in the tube lines with gaps of ≥15 mm without missing. It was shown by on-site inspection that the equipment was effectual.
Effect of CdCl2 heat treatment on ZnTe back electron reflector layer in thin film CdTe solar cells

Abstract The effect of CdCl2 heat treatment on the ZnTe layer used as the back electron reflector layer in polycrystalline CdTe solar cells was investigated. A thin film of ZnTe was grown on top of polycrystalline CdTe layer using metalorganic vapor phase epitaxy, which was then subjected to CdCl2 heat treatment. The effect was examined using various characterization techniques such as X-ray diffraction, energy dispersive X-ray spectroscopy and scanning electron microscope images and it was found that the ZnTe layer transformed into CdTe and ZnO due to the treatment. This was verified by performing CdCl2 heat treatment on pure ZnTe thin layer directly grown on glass which also showed the conversion of ZnTe to CdTe and ZnO. To study the effect of this transformation on final device performance, thin film CdTe solar cell structures were fabricated with ZnTe electron reflector layer with and without the CdCl2 heat treatment. The device without the ZnTe layer seemed to perform better than the devices with ZnTe layer and the CdCl2 heat treatment.
Social Class and Development in Early Adulthood: Some Unsettled Issues

This response to Jeffrey Arnett’s article on social class and the development of emerging adults points out a number of limitation in the data, analysis, and conclusions. For reasons outlined in my...
Catheter-Based Atrial Septal Defect Closure

Atrial septal defects (ASDs) are among the most common congenital heart defects in adults. Ostium secundum type ASDs account for 70 % of all defects and the majority are amenable to percutaneous closure. At present, non-secundum ASDs require surgical repair. Echocardiography has emerged as an essential imaging tool to characterize defect anatomy, measure ASD dimensions, identify candidates for percutaneous closure, and facilitate appropriate device selection. Intra-procedural echocardiographic guidance is critical to transcatheter closure. 3D transesophageal echocardiography offers significant advantages over 2-dimensional imaging by providing highly accurate representations of septal defects in the en face views.
Proximity-Based Authentication for Mobile Devices

While mobile handheld devices provide productivity benefits, they also pose new risks. User authentication is the best safeguard against the risk of unauthorized use and access to a device’s contents. This paper describes two location-based user authentication mechanisms designed to take advantage of Bluetooth functionality built into many current handheld devices.
Neuronal and Behavioral Effects of Amphetamine in Caenorhabditis elegans

Abstract Since amphetamine was discovered, a lot of studies have been carried out in an attempt to identify the mechanism of action of this drug. Studies with mammalian models have identified neurochemical systems and brain regions that mediate some of the addictive properties of amphetamine. Nevertheless, our understanding of how the multiple effects of amphetamine lead to addiction remains unclear. Recently, researchers have turned to the invertebrate model system Caenorhabditis elegans to dissect the mechanisms through which amphetamine modulates behaviors. Taking advantage of its relatively simple anatomy and the genetic tools offered by C. elegans, it is possible to perform drug-induced behavioral screens in multiple mutants. Moreover, in vivo imaging experiments and in vitro electrophysiology and biochemistry data performed in C. elegans neuronal cultures provide useful insights into the molecular components activated by amphetamine. A similar approach combining in vitro and in vivo analysis of multiple mutants would be extremely costly and time-consuming if done in mammalian mutants.
Enzyme design: Functional Frankensteins.

An artificial esterase with no known natural structural analogues has been formed via the homo-heptameric self-assembly of a designed peptide. This esterase represents the first report of a functional catalytic triad rationally engineered into a de novo protein framework.
Music Upper Limb Therapy—Integrated: An Enriched Collaborative Approach for Stroke Rehabilitation

Stroke is a leading cause of disability worldwide. It leads to a sudden and overwhelming disruption in one’s physical body, and alters the stroke survivors’ sense of self. Long-term recovery requires that bodily perception, social participation and sense of self are restored; this is challenging to achieve, particularly with a single intervention. However, rhythmic synchronization of movement to external stimuli facilitates sensorimotor coupling for movement recovery, enhances emotional engagement, and has positive effects on interpersonal relationships. In this proof-of-concept study, we designed a group music-making intervention, Music Upper Limb Therapy-Integrated (MULT-I), to address the physical, psychological and social domains of rehabilitation simultaneously, and investigated its effects on long-term post-stroke upper limb recovery. The study used a mixed-method pre-post design with one-year follow up. Thirteen subjects completed the 45-minute intervention twice a week for six weeks. The primary outcome was reduced upper limb motor impairment on the Fugl-Meyer Scale. Secondary outcomes included sensory impairment (two-point discrimination test), activity limitation (Modified Rankin scale), well-being (WHO well-being index), and participation (Stroke Impact Scale). Repeated measures ANOVA was used to test for differences between pre- and post-intervention, and one-year follow up scores. Significant improvement was found in upper limb motor impairment, sensory impairment, activity limitation, and well-being immediately post-intervention that persisted at 1 year. Activities of daily living and social participation improved only from post-intervention to one-year follow up. The improvement in upper limb motor impairment was more pronounced in a subset of lower functioning individuals as determined by their pre-intervention wrist range of motion. Qualitatively, subjects reported new feelings of ownership of their impaired limb, more spontaneous movement, and enhanced emotional engagement. The results suggest that the MULT-I intervention may help stroke survivors re-create their sense of self by integrating sensorimotor, emotional and interoceptive information, and facilitate long-term recovery across multiple domains of disability, even in the chronic stage post-stroke. Randomized controlled trials are warranted to confirm the efficacy of this approach. Clinical Trial Registration: National Institutes of Health, clinicaltrials.gov, NCT01586221.
Spectrum Allocation, Power Control, Routing, and Congestion Control for Wireless Networks with Duplexing Constraints

We develop distributed algorithms to allocate resources in multi-hop wireless networks so as to minimize the total cost. In order to observe the fundamental duplexing constraint, we first devise a spectrum allocation scheme that divides the whole spectrum into multiple sub-bands and activates conflict- free links on each sub-band. We show that the minimum number of required sub-bands grows asymptotically at a logarithmic rate with the chromatic number of network connectivity graph. A simple distributed and asynchronous algorithm is developed to feasibly activate links on the available sub-bands. We then develop node-based distributed algorithms for optimally controlling the transmission powers on active links for each sub-band, jointly with traffic routes and user input rates in response to channel states and traffic demands. We show that the algorithms asymptotically converge to the optimal operating point.
Optimization of detector surface for multi-pinhole cardiac SPECT: An NCAT study

Pinhole collimation is used in SPECT for small-animal imaging and more recently for human Cardiac SPECT. In pinhole collimation for SPECT, the system resolution function depends on the magnification, pinhole-diameter, the detector intrinsic resolution and depth of interaction. The magnification and the depth of interaction change with the surface geometry. Factors such as resolution and surface area can be optimized by changing the shape of the detector. The goal of this work is to formulate and optimize the detector surface geometry to minimize the system resolution, keeping a constant base of the detectors fitted on the similar base-radius pinhole collimator, given surface area constraints. We formulate the system resolution as a function of a height-function h, varying with ray-angle. We approximate this height function as a quadratic curve. We can then find the parameters of the quadratic that will minimize the resolution function subject to surface area constraints. Note once the resolution is optimized, it can be traded with sensitivity (if so desired) by opening the pinhole diameter. Our preliminary NCAT phantom reconstruction on the optimized and flat detectors placed on pinholes shows sensitivity gain factor of 1.6 for similar resolution. Specifically, our results for NCAT reconstruction of GATE simulations on spherical and flat detectors placed on pinholes corroborates our idea that using a curved detector behind a pinhole instead of a flat-one one would obtain significant advantages of resolution or dose-reduction, on an already ultra-fast system.
Meaningful Gamification in an Industrial/Organizational Psychology Course

Motivation and game research continue to demonstrate that the implementation of game design characteristics in the classroom can be engaging and intrinsically motivating. The present study assessed the extent to which an industrial organizational psychology course designed learning environment created with meaningful gamification elements can improve student perceptions of learning, course experience, and learning outcomes compared to a traditional course. A mixed analysis of covariance revealed that those in the gamified condition showed significantly higher perceptions of learning, engagement, and motivation than those in the traditional course. This research suggests that students can learn just as effectively as traditional courses but have more favorable and positive experiences in the course through more, novel, interactive teaching methods. Future research implications are discussed.
Psychopathic individuals exhibit but do not avoid regret during counterfactual decision making.

Psychopathy is associated with persistent antisocial behavior and a striking lack of regret for the consequences of that behavior. Although explanatory models for psychopathy have largely focused on deficits in affective responsiveness, recent work indicates that aberrant value-based decision making may also play a role. On that basis, some have suggested that psychopathic individuals may be unable to effectively use prospective simulations to update action value estimates during cost–benefit decision making. However, the specific mechanisms linking valuation, affective deficits, and maladaptive decision making in psychopathy remain unclear. Using a counterfactual decision-making paradigm, we found that individuals who scored high on a measure of psychopathy were as or more likely than individuals low on psychopathy to report negative affect in response to regret-inducing counterfactual outcomes. However, despite exhibiting intact affective regret sensitivity, they did not use prospective regret signals to guide choice behavior. In turn, diminished behavioral regret sensitivity predicted a higher number of prior incarcerations, and moderated the relationship between psychopathy and incarceration history. These findings raise the possibility that maladaptive decision making in psychopathic individuals is not a consequence of their inability to generate or experience negative emotions. Rather, antisocial behavior in psychopathy may be driven by a deficit in the generation of forward models that integrate information about rules, costs, and goals with stimulus value representations to promote adaptive behavior.
Supervised Learning Techniques in Mobile Device Apps for Androids

Mobile devices have become an integral part of our daily lives. Most people carry smartphones today almost everywhere; and have other mobile devices such as tablets, often more convenient than full-fledged laptops for work transit, short trips etc. This had led to development of apps for mobile devices, easy to download and access anywhere anytime. An important field improving human experiences on mobile devices is machine learning. This constitutes technqiues involving acquisition of knowledge, skills and understanding by machines from examples, guidance, experience or reflection to learn analogous to humans. Among learning paradigms herein, supervised learning comprises situations where labeled training samples are provided to administer the process, making it more regulated, similar to human instructors providing such examples with notions of correctness to guide human learners. Supervised learning techniques are useful in designing mobile apps as they entail guided examples capturing specific human needs and their reasoning in activities, e.g., classification. This paper gives a comprehensive review of a few useful supervised learning approaches along with their implementation in mobile apps, focusing on Androids as they constitute over 50% of the global smartphone market. It includes description of the approaches and portrays interesting Android apps deploying them, addressing classification and regression problems. We discuss the contributions and critiques of the apps and also present open issues with the potential for further research in related areas. This paper is expected to be useful to students, researchers and developers in mobile computing, human computer interaction, data mining and machine learning.
The development and flexibility of gaze alternations in bonobos and chimpanzees.

Infants’ early gaze alternations are one of their first steps towards a sophisticated understanding of the social world. This ability, to gaze alternate between an object of interest and another individual also attending to that object, has been considered foundational to the development of many complex social-cognitive abilities, such as theory of mind and language. However, to understand the evolution of these abilities, it is important to identify whether and how gaze alternations are used and develop in our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). Here, we evaluated the development of gaze alternations in a large, developmental sample of bonobos (N = 17) and chimpanzees (N = 35). To assess the flexibility of ape gaze alternations, we tested whether they produced gaze alternations when requesting food from a human who was either visually attentive or visually inattentive. Similarly to human infants, both bonobos and chimpanzees produced gaze alternations, and did so more frequently when a human communicative partner was visually attentive. However, unlike humans, who gaze alternate frequently from early in development, chimpanzees did not begin to gaze alternate frequently until adulthood. Bonobos produced very few gaze alternations, regardless of age. Thus, it may be the early emergence of gaze alternations, as opposed gaze alternations themselves, that is derived in the human lineage. The distinctively early emergence of gaze alternations in humans may be a critical underpinning for the development of complex human social-cognitive abilities.
Thermodynamic re-assessment of the Al-Co-W system

Abstract The Al-Co-W system and its binary sub-systems Al-Co, Al-W and Co-W were critically reviewed. The thermodynamic description of the Al-Co-W system including all three binaries was developed considering thermodynamic and constitutional data of the systems. Results from density functional theory calculations were employed to improve reliability of the descriptions. The Gibbs energy for the thermal vacancy (GVa) in the BCC_A2 phase is discussed. The revised descriptions obtained for the Al-W and Co-W systems describe the thermodynamic and phase equilibrium data well and are free of undesired artefacts for temperatures below 6000 K. The ordered γ’ phase of the Al-Co-W system is described as a metastable phase in the entire temperature range. The calculated Gibbs energy of the γ’ is only slightly above that of the equilibrium state, which indicates that there is good possibility of stabilizing the γ’ phase with the addition of γ’-stabilizing elements, such as Ti, Ta, Hf, Nb and Ni.
Multi-electron transfer photochemistry: Caught in the act

The accumulation of multiple redox equivalents is essential in photo-driven catalytic reactions such as solar water splitting. However, direct spectroscopic observation of a twice-oxidized species under diffuse illumination has proved elusive until now.
Abstract 13134: Impact of the American Heart Association’s 2007 Guidelines on the Practice of Dental Prophylaxis for the Prevention of Infective Endocarditis in Olmsted County, Minnesota

Background: In 2007, the American Heart Association (AHA) infective endocarditis (IE) prevention guidelines recommended that antibiotic prophylaxis before invasive dental procedures for the “moderate risk” (MR) group, which represented the bulk of patients who were to receive prophylaxis before 2007, be eliminated. This decision was met with much concern among some healthcare providers and that concern persists today. We therefore evaluated dental office records in Olmsted County (OC), Minnesota to determine whether patients included in the MR group continue to receive antibiotic prophylaxis despite the 2007 AHA recommendations. Methods: Eligible patients include all adult (≥18 years) residents of OC, classified as having MR cardiac condition for IE (i.e. mitral valve prolapse [MVP], bicuspid aortic valve [BAV], hypertrophic obstructive cardiomyopathy [HOCM], acquired valvular dysfunction [AVD]), with at least one dental visit between January 1, 2005 and June 1, 2015. Eight dental offices located within O...
Social Work Assistance in Private Pediatric Practice

Group and individual family services contribute toward the ultimate goal of providing preventive education and care in the area of improved family mental health
Chemoprevention of Barrett's oesophagus: a step closer with PPIs and aspirin.

Chemoprevention for patients with Barrett’s oesophagus remains a controversial topic. Results of the first randomized trial of chemoprevention using a proton pump inhibitor with or without aspirin were recently reported. We highlight strengths and weaknesses in the design of the trial and discuss the clinical implications of the findings.
Difficulties in defining mobile learning: analysis, design characteristics, and implications

Mobile learning, or m-learning, has become an umbrella term for the integration of mobile computing devices within teaching and learning. In the literature, however, use of the terms has been unsystematic. The purpose of this article is to critically examine the principles of mobile learning. First, I examine the extant literature with regard to defining mobile learning. Four definitions of mobile learning categories are described: (1) relationship to distance education and elearning, (2) exploitation of devices and technologies, (3) mediation with technology, and (4) nomadic nature of learner and learning. Second, in an effort to provide a basis on which to ground future mobile learning research, I propose a framework of design characteristics for mobile learning environments. Seven design characteristics are identified and discussed. Finally, I present implications for future research and instructional design. This paper contributes to the field of mobile learning by providing researchers more precise ways to identify and describe the characteristics of mobile learning environments, as well as describe the attributes of successful mobile learners.
Teaching Complexity as Transdisciplinarity

This paper describes how a course in complexity studies can teach the value of a broad education, and the benefits of synthesizing knowledge otherwise acquired in disciplinary silos. For students focused on one field or vocation, understanding complexity may provide the necessary perspective that links their field to other valuable methodologies. Teaching complexity allows both students and faculty to connect disciplinary expertise to a wider range of knowledge on how things work, giving them a more consilient approach to solving real-world problems. The proposed course demonstrates transdisciplinarity across disciplines to identify self-organizing networks and the emergence of bounded systems. Agent-based modeling is used to show students how basic algorithms can create complex orders, and how lower-level orders can give rise to higher levels of order that have new, unpredictable properties. Students are given a grounding in both thermodynamics and information processing to understand how any kind of self-organizing system may evolve according the same generative principles, be it an ecosystem, a stream of consciousness, an industry, or a genre of art. As students see the prevalence of self-organization and emergence across disciplines, they can share with faculty the sense that we are in a special moment where a new, more unified way of seeing things is taking shape. Both authors of this paper have taught several courses on complexity, including one that was taught jointly with faculty from six different disciplines at five different universities. The authors remark on what worked, what did not, and what could be improved, as well as providing a set of recommendations and resources for faculty who may be interested in teaching on this important subject.
Free Time and Physical Activity Among Americans 15 Years or Older: Cross-Sectional Analysis of the American Time Use Survey.

INTRODUCTION Many Americans fail to meet physical activity guidelines. We investigated whether this failure is due in part to a lack of free time. METHODS We analyzed data from the American Time Use Survey, 2014 through 2016, with 32,048 respondents aged 15 years or older, categorizing every activity during a 24-hour period. Free or leisure time includes time spent socializing, being entertained, in sports and recreation activities, volunteering, in religious activities, taking classes for personal interest, and in associated travel time. Working in the labor market, education (unless only for personal interest), household work and home production (cooking, cleaning, child care, shopping), or self-care (sleeping, eating, grooming) are not free time. We stratified by sociodemographic characteristics, health, and body mass index, and we calculated descriptive statistics adjusted for the multistage sampling design. RESULTS Americans averaged more than 5 hours (>300 minutes) of free time per day; no subgroup reported having less than 4.5 hours (270 minutes) of free time. Men had more free time (mean [standard deviation], 356 [3] min/d) and spent more on leisure time physical activity (mean [SD], 24 [3] min/d) than women did (free time mean [SD], 318 [2] min/d, P < .001; and leisure time physical activity mean [SD], 14 [1] min/d, P < .001). Compared with those with a higher income and a college education, those with income below 185% of federal poverty guidelines and those with a high school education reported more free time but spent more time on television, movies, and other screen time and less on physical activity (all comparisons P < .001). CONCLUSION Lack of free time is not responsible for low levels of leisure time physical activity at the population level.
Analysis of stock market data by using Dynamic Fourier and Wavelets techniques

Abstract This work deals with the analysis of daily and minute sampled financial stock market data. We propose a Dynamic Fourier Transform (DFT) and a Wavelet Transform to estimate the power spectrum of returns. In order to estimate the power spectrum, we used the tapering process with the DFT technique and the scaling function with the wavelets methodology to avoid the spectral leakage or discontinuity in the sequence. Our result suggest that the power spectrum are effective in characterizing the minute and daily based data corresponding to different frequencies. This type of modeling techniques help to characterize some key variables of stationary time series that are very useful for making informed decisions in the stock market such as assessing financial risk in the market.
Variation in Inca Building Stone Quarry Operations in Peru and Ecuador

Data from a number of Inca stone quarries are examined to explore the variability in Inca organization of the production of cut-stone building blocks in the heartland of Cusco, Peru and the southern highlands of Ecuador. Great variability is seen in the size of quarries, distance from construction sites, and the associated facilities constructed to support quarrying activities. In contrast, all quarries were similar in being located near major roads and steps of stone block preparation undertaken within the quarries. The cultural meanings and sacred nature of quarries and building stone is seen as an important dimension of the Inca approach to quarrying and using cut stone.
Extramammary Paget Disease: A Review of the Literature-Part I: History, Epidemiology, Pathogenesis, Presentation, Histopathology, and Diagnostic Work-up.

BACKGROUNDExtramammary Paget disease (EMPD) is a rare malignancy with unclear pathophysiology that occurs predominantly on apocrine rich skin. Surgery is the treatment of choice; however, procedures tend to be extensive and associated with a high rate of recurrence.OBJECTIVETo review the current lit