cssi/SciSciGPT-SciSciNet huggingface dataset:
Entrainment waves in decelerating transient turbulent jets

A simplified one-dimensional partial differential equation for the integral axial momentum flux during the deceleration phase of single-pulsed transient incompressible jets is derived and solved analytically. The wave speed of the derived first-order nonlinear wave equation shows that the momentum flux transient from the deceleration phase propagates downstream at twice the initial jet penetration rate. Transient-jet velocity data from the existing literature is shown to be consistent with this derivation, and an algebraic analytical solution matches the measured timing and decay of axial velocity after the deceleration transient. The solution also shows that a wave of increased entrainment accompanies the deceleration transient as it travels downstream through the jet. In the long-time limit, the peak entrainment rate at the leading edge of this ‘entrainment wave’ approaches an asymptotic value of three times that of the initial steady jet. The rate of approach to the asymptotic behaviour is controlled by the deceleration rate, which suggests that rate-shaping may be tailored to achieve a desired mixing state at a given time after the end of a single-pulsed jet. In the wake of the entrainment wave, the absolute entrainment rate eventually decays to zero. The local injected fluid concentration also decays, however, so that entrainment rate relative to the local concentration of injected fluid remains higher than in the initial steady jet. An analysis of diesel engine fuel-jets is provided as one example of a transient-jet application in which the considerable increase in the mixing rate after the deceleration phase has important implications.
Notes On Hain 4515 and Gw 7184

[In 1946, after a remarkable Odyssey during World War II, L. M. J. Delaisse joined the staff of the Royal Library of Belgium, where he quickly showed himself a worthy pupil of his mentors, the late Frederic Lyna and Francois Masai. His doctoral dissertation on Thomas a Kempis was published in 1956 (see note 1). Very soon he became a specialist in the field of Flemish miniatures (see, e.g., note 2), and an increasingly important contributor to the periodical Scriptorium. In 1959 he was invited to teach at Princeton University, and thereafter successive invitations took him to the University of California at Berkeley and to the Harvard University. From 1963 onwards he was a Fellow of All Souls College at Oxford, where he enjoyed working with a group of students on 'his' archaeology of the book., In 1946, after a remarkable Odyssey during World War II, L. M. J. Delaisse joined the staff of the Royal Library of Belgium, where he quickly showed himself a worthy pupil of his mentors, the late Frederic Lyna and Francois Masai. His doctoral dissertation on Thomas a Kempis was published in 1956 (see note 1). Very soon he became a specialist in the field of Flemish miniatures (see, e.g., note 2), and an increasingly important contributor to the periodical Scriptorium. In 1959 he was invited to teach at Princeton University, and thereafter successive invitations took him to the University of California at Berkeley and to the Harvard University. From 1963 onwards he was a Fellow of All Souls College at Oxford, where he enjoyed working with a group of students on 'his' archaeology of the book.]
Multiple drug use in a sample of experienced marijuana smokers.

It is generally recognized that drug abuse today is a multidrug problem but few studies have concentrated on multiple drug abuse by marijuana smokers. This article describes actual and anticipated drug use by a sample of marijuana smokers who have moved well beyond the novitiate stage. College students, prison inmates, and ghetto Blacks are the source of data. Marijuana smokers differed markedly along most of the lines investigated. Experienced marijuana smokers in this sample are involved in the drug scene in different ways. Data indicate that a drug-anticipation syndrome exists which is distinguishable from the non-drug-anticipators. Anticipators are already more involved in the drug world and evidence suggests that they may be vulnerable to experimentation with heroin.
Aqueous lamellar surfactant system for mediated electrolytic dechlorination of polychlorinated biphenyls

Utilisation d'un agent de surface cationique pour reduire electrochimiquement les composes polychlores
Update on AUA Guideline on the Management of Benign Prostatic Hyperplasia

Purpose: To revise the 2003 version of the American Urological Association's (AUA) Guideline on the management of benign prostatic hyperplasia (BPH).Materials and Methods: From MEDLINE® searches of English language publications (January 1999 through February 2008) using relevant MeSH terms, articles concerning the management of the index patient, a male ≥45 years of age who is consulting a healthcare provider for lower urinary tract symptoms (LUTS) were identified. Qualitative analysis of the evidence was performed. Selected studies were stratified by design, comparator, follow-up interval, and intensity of intervention, and meta-analyses (quantitative synthesis) of outcomes of randomized controlled trials were planned. Guideline statements were drafted by an appointed expert Panel based on the evidence.Results: The studies varied as to patient selection; randomization; blinding mechanism; run-in periods; patient demographics, comorbidities, prostate characteristics and symptoms; drug doses; other interve...
Determination of envelope to family of planar parametric curves and envelope singularities

Abstract A parametric family Σ φ of planar curves generated by the tool profile Σ r is considered. The generated profile Σ p of the workpiece (gear) is the envelope to the family Σ φ . The authors propose simplified approaches for determination of the envelope, its singularities and conditions of existence of a point of regression. The proposed developments are illustrated with the design and generation of Root's blowers.
Family dynamics and preadolescent girls with ADHD: the relationship between expressed emotion, ADHD symptomatology, and comorbid disruptive behavior

Background: Despite the strong biological underpinnings of attention-deficit/hyperactivity disorder (ADHD), family factors remain salient influences on the course of the disorder. However, relatively little is known about how family-level variables relate to ADHD in girls and whether these variables are linked primarily to core ADHD symptomatology or to comorbid aggressive conditions. Methods: We investigated the relationship between parental expressed emotion (EE), measured via the five-minute speech sample (FMSS), and ADHD as well as comorbid disruptive behavior disorders, in a diverse sample of 131 girls aged 6–12 years. Results: High parental EE was associated with both ADHD and aggression, whether these constructs were measured categorically or continuously. The EE component of criticism, as opposed to emotional overinvolvement (EOI), showed the stronger associations with both constructs. ADHD subtypes (Inattentive vs. Combined) were equivalent with respect to prediction from high EE status. Whereas linkages with EE were stronger for ADHD than for aggression and withstood control of comorbid aggression, the converse was not true – i.e., the link between EE and aggression did not hold with control of ADHD. Multiple regression analyses revealed that the associations were independent of parenting stress and maternal depression; exploratory analyses revealed interactions between EE and (a) maternal depression and (b) Child Verbal IQ with respect to predictions of disruptive behavior. Conclusions: These findings add to a growing body of literature on ADHD in girls and highlight a pivotal link between family dynamics and the spectrum of ADHD-related behaviors. They also indicate that inattentive symptoms may be equally challenging to parents as hyperactive/impulsive symptoms.
Histological study of muscular hypoplasia in the crooked neck dwarf mutant (cn/cn) chick embryo

Tibiotarsal segments of 12-day chick embryos homozygous for the crooked neck dwarf gene (cn/cn) were examined histologically following routine methods of preparation. The myogenic mass fails to divide into separate muscle bundles during the early stages of differentiation. Myoblasts and myotubes are observed, although the proportion favors the mononucleate cell population. Multinucleate myotubes are often wavy in appearance and many contain eosinophilic cytoplasmic inclusions. The entire tissue mass of mutants appears more compacted than in control limbs. Poor organization of muscle appears related to the lack of a suitable connective tissue system. Epimysia, perimysia, and subcutaneous connective tissue fail to develop properly. Tendons are poorly developed or absent. Comparisons between mutant and control embryos show no differences in peripheral innervation. Nerve fascicles penetrate deeply into the developing muscle of both species. The distribution of vascular elements is seemingly normal also. Skeletal muscle of cn/cn embryos is capable of differentiating to the myotube stage, after which it undergoes cellular degeneration without achieving a functional state. Comparisons of this mutant with alleged chemical phenocopies show important differences.
Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations

This paper presents recent advancement in and applications of TOUGH-FLAC, a simulator for multiphase fluid flow and geomechanics. The TOUGH-FLAC simulator links the TOUGH family multiphase fluid and heat transport codes with the commercial FLAC^3^D geomechanical simulator. The most significant new TOUGH-FLAC development in the past few years is a revised architecture, enabling a more rigorous and tight coupling procedure with improved computational efficiency. The applications presented in this paper are related to modeling of crustal deformations caused by deep underground fluid movements and pressure changes as a result of both industrial activities (the In Salah CO"2 Storage Project and the Geysers Geothermal Field) and natural events (the 1960s Matsushiro Earthquake Swarm). Finally, the paper provides some perspectives on the future of TOUGH-FLAC in light of its applicability to practical problems and the need for high-performance computing capabilities for field-scale problems, such as industrial-scale CO"2 storage and enhanced geothermal systems. It is concluded that despite some limitations to fully adapting a commercial code such as FLAC^3^D for some specialized research and computational needs, TOUGH-FLAC is likely to remain a pragmatic simulation approach, with an increasing number of users in both academia and industry.
SU‐E‐T‐95: Investigation of 3D Dosimetry for an Anthropomorphic Spine Phantom

Purpose: To evaluate 3D dosimetry for a spinal cord treatment plan delivery using the Radiological Physics Center's (RPC) anthropomorphic spine phantom. Methods: The RPC's spine phantom currently uses radiochromic film and thermoluminescent dosimeters(TLD) to evaluate spinal metastases treatments. A second dosimetry insert for the phantom was created to hold a PRESAGE® 3D dosimeter which matched the location of the TLD and film in the original insert. The phantom was CTimaged with each insert and an IMRT treatment plan was developed. The IMRT plan was delivered to the phantom twice; once with each insert. The film and PRESAGE® were scanned on a CCD microdensitometer and optical‐CT system, reconstructed to a 2 mm slice width, respectively. The measured dose distributions were compared to the treatment plan calculated dose distribution using RPC in‐house developed software or the Computational Environment for Radiotherapy Research (CERR). Film and PRESAGE® dose profiles were taken across several planes and compared for agreement. The distance to agreement (DTA) between the measured data and treatment plan, within the high dose gradient region, was quantified. Results: The PRESAGE® and plan dose profiles agreed to within 2and 1 mm in the AP and SI directions, respectively. The film and plan also agreed to within 2 mm across all profiles. Conclusions: The PRESAGE® 3D dosimeter, based on these preliminary data, shows potential as a dosimeter for the RPC's phantom irradiation studies. Future work will add markers to the PRESAGE® insert to allow for a reproducible registration in CERR and a an optical‐CT system, reconstructed to a 2 mm slice width dosecalibration protocol will be created. CA 100835
Localization and activity of the SNARE Ykt6 determined by its regulatory domain and palmitoylation

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) catalyze compartment-specific membrane fusion. Whereas most SNAREs are bona fide type II membrane proteins, Ykt6 lacks a proteinaceous membrane anchor but contains a prenylation consensus motif (CAAX box) and exists in an inactive cytosolic and an active membrane-bound form. We demonstrate that both forms are farnesylated at the carboxyl-terminal cysteine of the CCAIM sequence. Farnesylation is the prerequisite for subsequent palmitoylation of the upstream cysteine, which permits stable membrane association of Ykt6. The double-lipid modification and membrane association is crucial for intra-Golgi transport in vitro and cell homeostasis/survival in vivo. The membrane recruitment and palmitoylation is controlled by the N-terminal domain of Ykt6, which interacts with the SNARE motif, keeping it in an inactive closed conformation. Together, these results suggest that conformational changes control the lipid modification and function of Ykt6. Considering the essential and central role of Ykt6 in the secretory pathway, this spatial and functional cycle might provide a mechanism to regulate the rate of intracellular membrane flow.
Physiologically Relevant Structure of Alzheimer's Related Amyloid Protein and the Role of Embedded Water in Its Amphiphilc Pore

Various structural models for amyloid β fibrils have been derived from a variety of experimental techniques. However, these models cannot differentiate between the relative position of the two arms of the β hairpin called the stagger. Amyloid fibrils of various hierarchical levels form left-handed helices composed of β sheets. However it is unclear if positive, negative and zero staggers all form the macroscopic left-handed helices. To address this issue we have conducted extensive molecular dynamics simulations of amyloid β sheets of various staggers and shown that only negative staggers lead to the experimentally observed left-handed helices while positive staggers generate the incorrect right-handed helices. This result suggests that the negative staggers are physiologically relevant structure of the amyloid β fibrils. We further investigate the structure and dynamics of water embedded in the amphiphilic pore of Abeta and argue that this water is an integral component of the protein structure and not a fleeting entity.
Population genetics of the California National Primate Research Center’s (CNPRC) captive Callicebus cupreus colony

The California National Primate Research Center maintains a small colony of titi monkeys (Callicebus cupreus) for behavioral studies. While short tandem repeat (STR) markers are critical for the genetic management of the center's rhesus macaque (Macaca mulatta) breeding colony, STRs are not used for this purpose in the maintenance of the center's titi monkey colony. Consequently, the genetic structure of this titi monkey population has not been characterized. A lack of highly informative genetic markers in titi monkeys has also resulted in scant knowledge of the species' genetic variation in the wild. The purpose of this study was to develop a panel of highly polymorphic titi monkey STRs using a cross-species polymerase chain reaction (PCR) amplification protocol that could be used for the genetic management of the titi monkey colony. We screened 16 STR primer pairs and selected those that generated robust and reproducible polymorphic amplicons. Loci that were found to be highly polymorphic, very likely to be useful for parentage verification, pedigree assessment, and studying titi monkey population genetics, were validated using Hardy-Weinberg equilibrium and linkage disequilibrium analyses. The genetic data generated in this study were also used to assess directly the impact on the colony's genetic diversity of a recent adenovirus outbreak. While the adenovirus epizootic disease caused significant mortality (19 deaths among the 65 colony animals), our results suggest that the disease exhibited little or no influence on the overall genetic diversity of the colony.
Interaction of benzene and 1,2-bis(chloromercurio)tetrafluorobenzene. Supramolecular frameworks based on Hg⋯Cl, Hg⋯F, Hg⋯π and π–π interactions

The crystallization of 1,2-bis(chloromercurio)tetrafluorobenzene (1) from a mixture of THF and benzene yields 1·THF·0.5C6H6 (2), which contains the Lewis base–Lewis acid adduct 1·μ-THF associated to benzene. When 1 is crystallized from a mixture of propylene oxide and benzene, a compound of composition 1·1.5C6H6 (3) is obtained. Both 2 and 3 have been analyzed by solid-state 13C CP/MAS NMR spectroscopy and their structures have been investigated by X-ray crystallography. The solid state structure of 2 is that of a framework wherein layers of 1·μ-THF are linked by pillars of sandwiched benzene molecules. The cohesion of this framework results from the presence of intermolecular Hg⋯Cl interactions as well as arene-1,2-bis(chloromercurio)tetrafluorobenzene π–π stacking interactions. The crystal structure of 3 reveals the existence of parallel polymeric chains of 1 embedded in a benzene matrix in which the benzene molecules adopt an edge-to-face arrangement. The polymeric chains of 1 are formed by Hg⋯Cl and Hg⋯F interactions that link the monomers. Finally, part of the benzene molecules in 3 interacts with molecules of 1 by Hg⋯π rather than π–π stacking interactions.
Storytelling: Walter Benjamin and recovery from alcoholism

What follows is a critical review of alcoholism and recovery. The objective is to examine Benjamin's account of storytelling in light of the value of stories for recovering alcoholics. The research design is qualitative, and it is explained that, because storytelling requires experience of a vanishing sort, the design must be qualitative. The method is theoretical, drawing upon Benjamin's account of the societal changes that have brought about the disappearance of the storyteller such as the predominance of information. The main outcome is that the features of Benjamin's account of storytelling are evident in the body of experience that comprises recovery from alcoholism, but not in such a way that would suggest that his account of historical change is thereby null. In conclusion, the oases of storytelling in recovery provide evidence for the erosion of experience of the kind required to have stories.
Identification of Structural System Parameters Using the Cascade-Correlation Neural Network

he use of neural networks for structural system identification is receiving an increasing amount of attention through the research focused on structural control and intelligent systems. These systems require continuous monitoring and controlling of structural response; thus, on-line identification techniques are needed to provide real-time information about structural parameters. The Cascade-Correlation (Cascor) neural network is applied here to the structural system identification problem. The Cascor network utilizes a dynamic network architecture and a variable error threshold mechanism which facilitates training and can increase the network's ability to generalize
Structural Studies of Crystalline Linear Polyethylenes as Revealed by Factor Analysis of Their Raman Spectra

Seven samples of linear polyethylene which show quite different levels of crystallinity were prepared and Raman spectra of them were measured. The spectra of these samples show a series of narrow bands superimposed on very broad bands. This pattern is recognized to be the consequence of partial crystallization to give material consisting of lamellar crystallites connected with amorphous material. The narrow peaks are identical to those of crystalline polyethylene. The broad bands are identical to those of a polyethylene melt. Factor analysis of the spectra shows the existence of a third component which has a spectrum quite similar to that of the crystalline region. An estimation of the spectrum of this component is presented. It is based upon combinations of abstract factors and upon subtraction of the contributions by the two prominent components from mixture spectra. The third spectrum, attributed to an interfacial region surrounding the crystallites in which partial order exists, closely resembles that of crystalline polyethylene, but with somewhat broader peaks that are shifted in position.
Detailed Shoulder MRI Findings in Manual Wheelchair Users with Shoulder Pain

Shoulder pain and pathology are common in manual wheelchair (MWC) users with paraplegia, and the biomechanical mechanism of injury is largely unknown. Establishing patterns of MRI characteristics in MWC users would help advance understanding of the mechanical etiology of rotator cuff disease, thus improving the logic for prescribed interventions. The purpose of this study was to report detailed shoulder MRI findings in a sample of 10 MWC users with anterolateral shoulder pain. The imaging assessments were performed using our standardized MRI Assessment of the Shoulder (MAS) guide. The tendon most commonly torn was the supraspinatus at the insertion site in the anterior portion in either the intrasubstance or articular region. Additionally, widespread tendinopathy, CA ligament thickening, subacromial bursitis, labral tears, and AC joint degenerative arthrosis and edema were common. Further reporting of detailed shoulder imaging findings is needed to confirm patterns of tears in MWC users regarding probable tendon tear zone, region, and portion. This investigation was a small sample observational study and did not yield data that can define patterns of pathology. However, synthesis of detailed findings from multiple studies could define patterns of pathological MRI findings allowing for associations of imaging findings to risk factors including specific activities.
Does the use of dolls facilitate children's memory of visits to the doctor?

Age differences in children's recall of salient experiences have frequently been documented, but these findings have routinely been based on studies in which verbal interviews have been employed. Because verbal interview protocols may underestimate the memory of young children, the purpose of this research was to compare the effectiveness of such an interview with two alternative protocols that involved the use of a doll. Using these contrasting protocols, 3-and 5-year-old children were asked to remember the details of a routine physical examination. Neither doll protocol facilitated 3-year-olds' recall of the features of the check-up. In contrast, 5-year-olds who were asked to demonstrate with a doll what happened in their examination showed enhanced recall. The inclusion of a doll had no effect on older or younger children's provision of elaborative detail about their visits to the doctor. Various measures of individual differences (e. g. temperament, language skill) predicted some aspects of the children's recall and elaboration. The findings are discussed in terms of the cognitive skills necessary for effective use of dolls in the assessment process, and are related to problems associated with interviewing young children who are involved in legal proceedings. Language: en
Carney complex and the familial lentiginosis syndromes: link to inherited neoplasias and developmental disorders, and genetic loci

Chrousos GP, Stratakis CA (National Institutes of Health, Bethesda, MD, USA). Carney complex and the familial lentiginosis syndromes: link to inherited neoplasias and developmental disorders, and genetic loci (Minisymposium: MEN & VHL). J Intern Med 1998; 243: 573–9. Lentigines, synonymous but not identical to freckles or ephelides, are common skin lesions. In a small number of patients, however, these lesions constitute part of genetic syndromes that are associated with inherited forms of neoplasias or other pathologic processes of the cardiovascular, endocrine, and gastrointestinal systems. The familial lentiginoses, as these syndromes are collectively known, include Carney complex, the LEOPARD and Peutz–Jeghers syndromes, and the newly described ‘syndrome of arterial dissections with lentiginosis’; isolated, familial lentiginosis has also been described. In the majority of the reported kindreds with these syndromes, the lesions were inherited in an autosomal dominant manner. The specific genes that are responsible for these disorders have remained elusive, but the genetic loci of Carney complex and Peutz–Jeghers syndromes were recently identified on chromosomes 2p 16 and distal 19p, respectively. Cytogenetic studies of tumours from patients with Carney complex suggest that the gene responsible for most patients with this syndrome may not have a tumour suppression function. We suggest that the genes responsible for the lentiginosis syndromes are important regulators of melanocyte function, they participate in the pleiotropy of human pigmentation, and are involved in the function, growth and proliferation of neural crest and mesenchymal cells.
The Concentration and Isotopic Abundances of Carbon Dioxide in the Atmosphere

A systematic variation with season and latitude in the concentration and isotopic abundance of atmospheric carbon dioxide has been found in the northern hemisphere. In Antarctica, however, a small but persistent increase in concentration has been found. Possible causes for these variations are discussed.
The Marketing of Parochial Schooling Modeled as an Exchange Process

An old adage has it that “necessity is the mother of invention.” This aphorism may in part account for the increased interest of church school educators in the discipline of marketing as an aid in stimulating demand for their product. Drawing from social exchange theory, the framework below explores the link between sociology, marketing, and education in explaining why people choose education in parochial schools.
Definition De La Classe Syntaxique D'Une Forme Lexicale a Partir De Sa Terminaison Graphique

Defining the syntactic class of a lexical form by means of its graphic ending: In order to recognize the syntactic class of a word, a statistical study on a corpus of over 150,000 words has been performed. The result of various experiments is reported, essentially the rate of recognition for endings of length 1 to 5.
Solvation of glycyl zwitterion with water

Abstract Low-temperature Monte Carlo simulation of the gas-phase solvated glycyl zwitterion predicts water aggregation into hydrogen bonded hexamers which encapsulate the zwitterion. Several water molecules distort to produce charge separation to offset the dipole of the zwitterion.
Isolation and cytotoxic evaluation of marine sponge-derived norterpene peroxides

The marine sponge Diacarnus cf. spinopoculum has provided a series of norterpenes, including five new compounds (7-11), two new ent-compounds [(-)-1a and (+)-1b], and three known compounds (2a, 2b, and 12). Eight of these compounds represent additional examples of the muqubilin/sigmosceptrellin classes (norsesterterpene peroxides) or the nuapapuin class (norditerpene peroxides). Also isolated were dinorditerpenones 11 and 12, which are biosynthetically related to the muqubilin/sigmosceptrellin structure classes. In all, 11 compounds were evaluated for their cytotoxic properties using a soft agar assay system and the NCI's 60 cell-line screen. Compounds without peroxide functionality were inactive. Overall, the norsesterterpene peroxides were less selective as cytotoxins than norditerpene peroxide analogues. Two compounds, nuapapuin A methyl ester (3) and nuapapuin B (7), which were somewhat selective in their cytotoxic behavior, were selected for further in vivo evaluation.
Creating an Integrative Curriculum: Making the Connections

The move to an integrative curriculum must start with interested teachers and administrative support. In addi tion, we must stop thinking about such arrangements as "experimental," this writer warns.
Clinical PathoScope: rapid alignment and filtration for accurate pathogen identification in clinical samples using unassembled sequencing data.

The use of sequencing technologies to investigate the microbiome of a sample can positively impact patient healthcare by providing therapeutic targets for personalized disease treatment. However, these samples contain genomic sequences from various sources that complicate the identification of pathogens. Here we present Clinical PathoScope, a pipeline to rapidly and accurately remove host contamination, isolate microbial reads, and identify potential disease-causing pathogens. We have accomplished three essential tasks in the development of Clinical PathoScope. First, we developed an optimized framework for pathogen identification using a computational subtraction methodology in concordance with read trimming and ambiguous read reassignment. Second, we have demonstrated the ability of our approach to identify multiple pathogens in a single clinical sample, accurately identify pathogens at the subspecies level, and determine the nearest phylogenetic neighbor of novel or highly mutated pathogens using real clinical sequencing data. Finally, we have shown that Clinical PathoScope outperforms previously published pathogen identification methods with regard to computational speed, sensitivity, and specificity. Clinical PathoScope is the only pathogen identification method currently available that can identify multiple pathogens from mixed samples and distinguish between very closely related species and strains in samples with very few reads per pathogen. Furthermore, Clinical PathoScope does not rely on genome assembly and thus can more rapidly complete the analysis of a clinical sample when compared with current assembly-based methods. Clinical PathoScope is freely available at: http://sourceforge.net/projects/pathoscope/ .
Teaching an introductory programming course using hybrid e-learning approach

The usefulness of hybrid delivery in education has long been realized, and with the advancement of computer and communication technologies and the introduction of Web-based authoring tools, its effectiveness has been further extended. In this regard, it has affected traditional distance learning by transforming the learning experience from a static videotape delivery to a more dynamic format by adding/substituting the web as the delivery media. In this paper, we report our initial results based on offering an introductory computer programming course for engineers using Matlab; via hybrid e-learning including virtual face-to-face, for distance course delivery. We present the challenges that teaching a programming course brings about using a hybrid methodology with synchronous online delivery component. Details of this work, including design and delivery issues, student and course assessment, and required technology, as applied to a computer programming course, are included in the paper.
Measuring ADAMTS13 activity in patients with suspected thrombotic thrombocytopenic purpura: when, how, and why?

During the past 17 years, thrombotic thrombocytopenic purpura (TTP) has become defined by a severe deficiency of ADAMTS13.1 However this definition is not equivalent to a diagnosis of TTP. ADAMTS13 measurements have become common in our evaluation and management of patients with suspected TTP, but there are still uncertainties about the interpretation of these measurements. To address these uncertainties, we need to consider three questions. Addressing these questions is something that clinicians do whenever seeing a patient for whom the question is, “Does she have TTP?”
Thermal stress as the major factor of defect generation in SiC during PVT growth

Numerical simulations of the thermal stress distribution in a SiC boule 2” in diameter and 1” long grown by conventional PVT technique were performed based on the temperature field distribution in a resistively heated growth reactor that was simulated using the GAMBIT-2.0.4/FIDAP-8.6.2 software package. Analysis of the simulation results revealed the existence of a thermal stress, which was excessively nonuniform in distribution and whose magnitude exceeded the value of the critical resolved shear stress of 1.0 MPa by a factor of 2. The high stress initiated plastic deformation and the high temperature provoked the intense self-diffusion processes. The combination of these factors alters the mechanism of plastic deformation, significantly affecting the structural quality of the growing crystal. The influence of self-diffusion processes initiating the formation of interstitial atoms and vacancies; stacking fault formation as a result of the nonconservative motion of the basal plane dislocations; and micropipe formation from the dislocation groups piled up at silicon and carbon second phase inclusions are also discussed.
Dynamic range of achievable impedances in force-reflecting interfaces

This paper addresses the performance of force-reflecting interfaces (`haptic displays'). We suggest that an important measure of performance is the dynamic range of achievable impedances, and that an impedance is achievable if it satisfies a robustness property such as passivity. The effects of sampling, inherent interface dynamics, and sensor quantization on dynamic range are discussed. Techniques for achieving very high impedances are presented.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Using Excel to Simulate Pendulum Motion and Maybe Understand Calculus a Little Better

As part of a first-year college Introductory Physics course, I have students construct an Excel®: spreadsheet based on the differential equation for pendulum motion (we take a pendulum having a light bar rather than a string, so it can go ‘over the top’). In extensive discussions with the students, I find that forcing them to make the spreadsheet themselves, entering velocities as position differences divided by time, etc., leads to a firmer grasp of basic calculus concepts. And, the instant graphical response of the finished product gives a sense of accomplishment as well as a lot of fun while building intuition about pendulum motion.
Oxidative Coupling of Methane over Oxide-Supported Sodium-Manganese Catalysts

The oxidative coupling of methane over Mn/Na{sub 2}WO{sub 4}/SiO{sub 2}, Mn/Na{sub 2}WO{sub 4}/MgO, and NaMnO{sub 4}/MgO catalysts was studied using both a cofeed flow system and a pulse reactor. At 800{degrees}C and 1 atm, and using a CH{sub 4}/O{sub 2} ratio of ca. 8/1, a methane conversion of 20% was achieved at a C{sub 2+} selectivity of {ge}80%, with no diluent in the reagents. The similar catalytic behaviors of the three catalysts suggest that a common active site, consisting of an Na-O-Mn species, may be involved. Results from a pulse reaction sequence (an O{sub 2} pulse followed by a series of pure CH{sub 4} pulses) indicate that the active species are not stable under reaction conditions unless gas phase O{sub 2} is present, and that bulk lattice oxygen does not participate in the methane coupling reaction when carried out in the cofeed mode. There is a linear relationship between the specific activity for CH{sub 4} conversion and the concentration of surface Mn, which is believed to be responsible for the activation of O{sub 2}. The resulting form of oxygen then abstracts a hydrogen atom from CH{sub 4}. Sodium is essential for preventing the complete oxidation of CH{sub 4}, perhaps bymore » isolating the Mn ions. The tungstate ions appear to impart stability to the catalysts. 39 refs., 11 figs., 5 tabs.« less
Energetics of formation and hydration of ion-exchanged zeolite Y

Abstract Cationic variants of zeolite Y (LiY, NaY, KY, RbY, CsY, CaY, LaY and HY) were prepared via aqueous ion exchange. High-temperature calorimetry was used to study the integral hydration enthalpy and the enthalpy of formation from the constituent oxides. For the alkali cation-exchanged zeolites, the total energetic contribution by hydration decreases in the order LiY>NaY>RbY>CsY. However, the average hydration enthalpy per mole of water has little dependence on the nature of the exchanged cations. In the presence of smaller cations (higher ionic potential), water molecules can be packed more efficiently in zeolite cavities, and the average hydration number (H2O/M) is higher. The low hydration enthalpy of KY relative to the trend of the zeolites exchanged with other alkali cations may be due to the absence of a stable cation–water arrangement in sodalite cages. The enthalpy of formation of a zeolite from its constituent oxides becomes more exothermic as the basicity of the exchanged cations increases. For the alkali cation exchanged zeolites, the enthalpies of formation can be correlated to the average ionic potential, (Z/r)av. The standard formation enthalpies of the ion-exchanged zeolites from constituent elements at 25°C were derived by combining the calorimetric data with literature data. The hydration enthalpies and enthalpies of formation of CaY, LaY and HY are also presented.
Reshaping as a 3D fabrication technique

In this work, a new micromachining technology, namely reshaping, which combines advantages of two-dimensional IC fabrication with the third dimension of the mechanical world, is investigated in detail. With the new technology, surface micromachined and released polysilicon structures are deformed with external forces and then they are annealed to any desired 3D shape by Joule heating generated by the current through the devices. A similar technique was proposed before, however a detailed investigation is given in this work. Other available 3D fabrication techniques (e.g. LIGA) are expensive and there are still many challenges to overcome. In order to understand the reshaping process, polysilicon layers, whose crystallographical structure was modified by doping and annealing, were utilized. U-shaped cantilever beam microactuators were fabricated, reshaped and tested. Reshaping process was carried out at varying power levels with varying current pulse durations. Experimental results showed that microstructures in the desired shape with the optimized elastic properties can be obtained by controlling recrystallization, grain growth and plastic deformation parameters, which play a major role in reshaping.
Monolithically integrated graded-index waveguide input couplers for silicon-photonics

A monolithically integrated asymmetric graded index (GRIN) waveguide structure for coupling light into high index contrast waveguides is described. When analyzed in terms of its waveguide modes, the GRIN coupler is shown to be a multimode interference (MMI) device. The design parameters and tolerances are calculated for quadratic index profile and uniform index amorphous silicon (a-Si) GRIN couplers optimized for coupling light into silicon-on-insulator waveguides. Calculations of coupling efficiencies into 0.5 μm SOI waveguides show that asymmetric GRIN couplers operate over a very wide wavelength range with low polarization dependence, and fabrication requires lithographic resolution of only ±1 μm. Experimental results are presented for a 3 μm thick single layer a-Si coupler integrated with a 0.8 μm SOI waveguide. The measured variation of coupling efficiency with coupler length is in agreement with theory, with an optimal coupling length of 15 μm.
Multiple spindle cell lipomas and dermatofibrosarcoma protuberans within a single patient: Evidence for a common neoplastic process of interstitial dendritic cells?

This case report describes a 48-year-old man with multiple spindle cell lipomas of the neck and a dermatofibrosarcoma protuberans (DFSP) with fibrosarcomatous transformation of the chest. The presence of familial and nonfamilial multiple spindle cell lipomas within a single patient is a rare event, with only two reports in the current literature. This case represents the first report of multiple spindle cell lipomas occurring in association with a DFSP. It is of particular interest in that both spindle cell lipoma and DFSP represent, at least in part, neoplastic proliferations of CD34(+) spindled cells. The exact nature and differentiation of these spindled cells remains controversial, but prior studies have suggested that they could represent neoplastic interstitial dendritic cells. The association of DFSP and spindle cell lipoma within this single patient suggests that these two tumors (and their histologic variants) may well be linked, conceptually, as neoplastic proliferations of CD34(+) interstitial dendritic cells.
Incorporating component reuse, remanufacture, and recycle into product portfolio design

Product take-back laws have been enacted in the Netherlands, and the European Commission is expected to follow suit. The legislation mandates that manufacturers bear the economic burden of collection and disposal of products at the end of their useful lives. Reuse or remanufacturing of some components might be more cost-effective than disposal and provide an opportunity for recovery of their economic value. However, manufacturers have not traditionally engaged in the long-range planning over several product lifecycles that cost-effective reuse or remanufacturing requires. This paper develops a model for incorporating long-range planning for component reuse in product design. The model employs a product portfolio approach based on market segmentation, rather than a single product. The model is embedded in a decision tool that aids in determining when a product should be taken back, and which components should be reused, recycled, or disposed. A case study of a line of personal computers (PCs) demonstrates an implementation of the model. It also shows that if product take-back is mandated, it is in the PC manufacturer's best interest to shift from selling a product to essentially selling a service by controlling when the product is taken back and, thus, effectively creating a leasing program. The portfolio approach creates opportunities for the design engineer to distribute the cost, reliability, and environmental impacts of component reuse, remanufacture, and recycling in such a way that the end result is higher customer satisfaction than designing one product for all customer groups.
States, international organisations and the refugee: reflections on the complexity of managing the refugee crisis in the Horn of Africa

This article explores the complexity of managing refugee issues, particularly refugee repatriations, taking the Horn of Africa as a case. I argue that refugee repatriation endeavours are complex because their success depends on at least four actors, each with different indeed often conflicting interests. I examine the proposition that as the number of actors involved in a given issue area increases so does the likelihood of less-than-successful outcomes. This is particularly true if resource-poor actors are included in the decisionmaking process, and, because of the need to extract maximum benefits and/ or minimise maximum losses, usually operate under the assumption of zerosum situations. This assumption narrows their range of responses and hampers their ability to engage in mutually beneficial exchange relationships. As a result, repatriations, which are necessarily consensusbased, become more difficult to accomplish successfully as evidenced in the Horn of Africa.
Secure cell relay routing protocol for sensor networks

Past researches on sensor network routing have been focused on efficiency and effectiveness of data dissemination. Few of them considered security issue during the protocol design time. Security is very important for many sensor network applications. Studies and experiences have shown that considering security during design time is the best way to provide security for routing. In this paper, we present a novel secure cell relay (SCR) routing protocol for sensor networks. SCR routing protocol is resistant to several kinds of attacks on sensor networks, including selective forwarding, sinkhole, wormhole, Sybil, hello flooding attacks, etc. SCR is also an energy efficient routing protocol with acceptable security overhead. SCR routing utilizes the fact that sensor nodes (in most sensor networks) are dense, static and location-aware, to achieve good security, high delivery ratio and low energy consumption, which is confirmed by our simulations.
Better than ever? Employee reactions to ethical failures in organizations, and the ethical recovery paradox

This research examines organizational attempts to recover internally from ethical failures witnessed by employees. Drawing on research on service failure recovery, relationship repair, and behavioral ethics, we investigate how witnessing unethical acts in an organization impacts employees and their relationship with their organization. In two studies—one in the lab and one in the field—we examine the extent to which it is possible for organizations to recover fully from these ethical lapses. Results reveal an ethical recovery paradox, in which exemplary organizational efforts to recover internally from ethical failure may enhance employee perceptions of the organization to a more positive level than if no ethical failure had occurred.
Topography of nucleic acid helices in solutions. IV. Effect of polyamines on RNase-catalyzed hydrolysis of polyadenylic acid.

The effect of polyamines on the ribonuclease-catalyzed hydrolysis of polyriboadenylic acid, cytidine-2′,3′-cyclic phosphate, and cytidylyl-3′,5′-adenosine phosphate (CpA) is reported. It is found that the salts, (I) inhibit the rate of hydrolysis of polyadenylic acid, whereas the hydrolysis of cytidine-2′,3′-cyclic phosphate, and CpA is accelerated. It is concluded that polyamines inhibit the RNase-catalyzed hydrolysis of polyadenylic acid by binding to adjacent phosphate anions of the polynucleotide. The effect of other polyamines, i.e., the substituted salts (II) (where R = Me, Et, Pr, Bu, Pen, and —CH2CH2OH), (III) , spermidine, and spermine, on the RNase-catalyzed hydrolysis of polyadenylic acid was studied at 37 and 50°C. At 37°C., maximum inhibition of the hydrolytic reaction occurs at n = 4 for the salts I and II. At 50°C., maximum inhibition of the RNase-catalyzed hydrolysis of polyadenylic acid occurs at n = 3 for the unsubstituted salts I and the salts II where R = Et, and shifts to n = 2 for the salts II where R = Pr. Increasing the size of the substituent R of the salts, II, enhances the degree of inhibition. Substituting —CH2CH2OH for Et or Pr of the salts, II, decreases the extent of inhibition. Spermine and spermidine interact at very low concentrations with polyadenylic acid, causing significant inhibition of the RNase reaction. The result suggests that they interact with four and three adjacent negative charges of the polynucleotide, respectively. It is concluded that the salts, interact with polyadenylic acid by electrostatic, hydrogen bonding, and hydro-phobic forces. The electrostatic and hydrogen-bonding interactions are important for binding the salts where R1R2 and R3 are small, i.e., H. Hydrophobic interactions are very important in binding the highly substitutde salts (II and III). The above results are compared with those obtained from the melting of rA–rU and rA–rU2 in the presence of the salts I and II. The following conclusions may be made: (1) the surface of a multistranded helix is more polar than that of the single strand; (2) the Tm of a helix–coil transition in the presence of the diammonium salts depends mainly on the interaction of the latter with the helix; (3) the overall structure of polyadenylic acid at pH 6.20 does not appear to change significantly upon forming the multistranded helices, rA–rU and rA–rU2.