cssi/SciSciGPT-SciSciNet huggingface dataset:
Interprofessional Primary Care Course Curriculum and Evaluation.

BACKGROUND AND OBJECTIVES Primary care (PC) requires interprofessional teamwork and training. Although clinical training in PC settings is well developed in some professions, classroom teaching on the principles and practice of PC provides additional opportunities for interprofessional education. METHODS We offered an elective one-credit classroom course on PC over 3 years, 2013 through 2015, enrolling students from dentistry, medicine, nursing, pharmacy, physician assistant, public health, social work, and other fields. Course activities included classroom presentations, small group discussions, team exercises, written reflections, online discussion, and observation visits to PC practices. We conducted an anonymous postcourse evaluation using 5-point Likert-like scales and brief student comments. RESULTS Eighty-four students completed the course over 3 years and 86% (72) completed the evaluation. Students rated the course high value or very high value, particularly for interprofessional student mix (99%, 71) and practice visit (99%, 70/71). Most students (98% , 65/66), felt the course should be offered again, and 82% (54/66) thought it should be expanded. Most students (93%, 65/70), recommended the course for others, and 41.1% (29/70) felt it should be required for students in their field or for all health professions students. After completing the course, 83.3% (60/72) of students planned careers in PC settings, and 55.6% (40/72) reported they changed plans to such careers. CONCLUSIONS The PC course served students across health professions, earned high ratings, and influenced PC career plans. Most students felt the course should be recommended or required for all health professions students.
The Turnout Gap in Surveys: Explanations and Solutions

Postelection surveys regularly overestimate voter turnout by 10 points or more. This article provides the first comprehensive documentation of the turnout gap in three major ongoing surveys (the Ge...
Uninsured Children at School

Ten-year old Jack appeared at the school nurse’s office with a complaint of “being sick.” His teacher indicated that Jack was a new student of just over 2 weeks and had been having some trouble adjusting as well as not paying attention in class. The nurse noticed that Jack did not have a jacket on, despite the cold weather, and was rather quiet and unable to make eye contact with the nurse. He had no objective symptoms of illness. In addition, the nurse saw that there was no contact number for Jack’s parents. Jack rested for the rest of the afternoon, and his older sister tracked him down at the end of the day. She mentioned that they had just moved to the town with their grandparents, and led Jack out of the nurse’s office.
The Physiology of Endocrine Therapy

The near truth of Messr. Brown-Sequard’s credo has only recently become recognized with the rapidly expanding knowledge of the prostaglandins and related compounds. Brown-Sequard was notable on several levels (Olmsted, 1946). He was the last in the line of great French experimentalists who dominated physiology during the 19th century. At the age of 62, he ascended to the Chair of Medicine at the University of Paris vacated by the death of his contemporary and rival, Claude Bernard. He had an intuitive conviction that the nervous and endocrine systems were intimately associated. And he, probably more than any other, was responsible for the burgeoning interest in the physiological effects of organ extracts that ultimately led to the identification of hormones. Indeed, 30 years before Banting and Best, he attempted to reverse the symptoms of diabetes with pancreatic extracts.
Designing Spatially Distributed Gene Regulatory Networks To Elicit Contrasting Patterns

Pattern formation and differential interactions are important for microbial consortia to divide labor and perform complex functions. To obtain further insight into such interactions, we present a computational method for simulating physically separated microbial colonies, each implementing different gene regulatory networks. We validate our theory by experimentally demonstrating control over gene expression patterns in a diffusion-mediated lateral inhibition circuit. We highlight the importance of spatial arrangement as a control knob for modulating system behavior. Our systematic approach provides a foundation for future applications that require understanding and engineering of multistrain microbial communities for sophisticated, synergistic functions.
Time is money: quantifying savings in outpatient appendectomy.

Background Laparoscopic appendectomy can be performed on a fast-track, short-stay, or outpatient basis with high success rates, low morbidity, low readmission rates, and shorter length of hospital stay. Cost savings from outpatient appendectomy have not been well described. We hypothesize that outpatient laparoscopic appendectomy is associated with cost savings. Methods We performed an original retrospective cohort analysis of patients undergoing laparoscopic appendectomy between June 2013 and April 2017 at our academic medical center before and after implementation of an outpatient protocol which began on January 1, 2016. We assessed appendicitis grade, length of stay (LOS), cost, net revenue, and profit margin. Results After protocol implementation, the percentage of patients discharged from the the postanesthesia care unit (PACU) increased from 3.7% to 29.7% (χ2 p Discussion Outpatient appendectomy saves approximately $1000 per patient. Adoption of an outpatient appendectomy pathway is likely to be gradual, but will result in incremental improvement in resource utilization immediately. Grade does not predict which patients should be observed. Considering established safety, our data support widespread implementation of this protocol. Level of evidence III.
Recent Advances in Electrochemical Sensors for Detecting Toxic Gases: NO₂, SO₂ and H₂S.

Toxic gases, such as NOx, SOx, H2S and other S-containing gases, cause numerous harmful effects on human health even at very low gas concentrations. Reliable detection of various gases in low concentration is mandatory in the fields such as industrial plants, environmental monitoring, air quality assurance, automotive technologies and so on. In this paper, the recent advances in electrochemical sensors for toxic gas detections were reviewed and summarized with a focus on NO2, SO2 and H2S gas sensors. The recent progress of the detection of each of these toxic gases was categorized by the highly explored sensing materials over the past few decades. The important sensing performance parameters like sensitivity/response, response and recovery times at certain gas concentration and operating temperature for different sensor materials and structures have been summarized and tabulated to provide a thorough performance comparison. A novel metric, sensitivity per ppm/response time ratio has been calculated for each sensor in order to compare the overall sensing performance on the same reference. It is found that hybrid materials-based sensors exhibit the highest average ratio for NO2 gas sensing, whereas GaN and metal-oxide based sensors possess the highest ratio for SO2 and H2S gas sensing, respectively. Recently, significant research efforts have been made exploring new sensor materials, such as graphene and its derivatives, transition metal dichalcogenides (TMDs), GaN, metal-metal oxide nanostructures, solid electrolytes and organic materials to detect the above-mentioned toxic gases. In addition, the contemporary progress in SO2 gas sensors based on zeolite and paper and H2S gas sensors based on colorimetric and metal-organic framework (MOF) structures have also been reviewed. Finally, this work reviewed the recent first principle studies on the interaction between gas molecules and novel promising materials like arsenene, borophene, blue phosphorene, GeSe monolayer and germanene. The goal is to understand the surface interaction mechanism.
Transradial access for neurointerventions: management of access challenges and complications.

Background Numerous large randomized trials have shown a significant morbidity and mortality benefit with the transradial approach (TRA) over the transfemoral approach (TFA) for endovascular procedures. However, this technique is routinely avoided or aborted due to unfamiliarity with the technique and the associated anatomical difficulties that may be faced in this approach. The objective of this review is to identify both the common and uncommon challenges that may be encountered during a transradial approach for cerebrovascular catheterization and to provide tips and tricks to overcome the transradial learning curve. Method A careful review of the literature and of all our transradial cases was carried out to identify the common challenges and complications that are encountered when using TRA for diagnostic cerebral angiography and neurointerventions. Results A stepwise approach is provided to prevent and manage common challenges including radial artery access failure, radial artery spasm, radial artery anomalies and tortuosity, radial artery occlusion, radial artery perforation and hematoma, subclavian tortuosity and anomalies, and catheter knots and kinks. Conclusion The ability to recognize and navigate anatomical variations and complications unique to TRA will accelerate learning, decrease unnecessary morbidity and mortality, and further advance the neurovascular field.
Prenatal use of cleaning and scented products and its association with childhood asthma, asthma symptoms, and mental health and developmental comorbidities

Introduction: Occupational use of cleaning chemicals has been related to asthma in adults. However, little information is available on the effect of non-occupational use of cleaning products during...
Dying Well: Our Journey of Love and Loss: by Hoben, S. D. Collinsville, CT, Canton Press, 2018, 280 pp., $20.14 (paperback)

Dying Well: Our Journey of Love and Loss was written as an account of the dying time for a much loved family member. In a society and time where death is whitewashed, avoided, and denied, this book...
Modern African art and apartheid

As early as the 1920s and 1930s, some artists in Africa began attracting attention for their work in ink or paint on paper or canvas: Aina Onabolu (1882–1963) from Nigeria; John Koenakeefe Mohl (19...
Expediting Training Using Information Theory Based Patch Ordering Algorithm

We present a framework for automatically ordering image patches that enables in-depth analysis of dataset relationship to learnability of a classification task using convolutional neural network. Our preliminary experimental results show that an informed smart shuffling of patches at a sample level can expedite training by exposing important features at early stages of training. Using multiple network architectures and datasets, we show that ordering image regions using mutual information measure between adjacent patches, enables CNNs to converge in a third of the total steps required to train the same network without patch ordering.
Price and marginal cost effects of on-time performance: Evidence from the US airline industry

Abstract We examine the impact of flight delay on market power in the U.S. airline industry. Consistent with the literature, our estimation results confirm that flight delays are associated with negative consumer welfare effects. Most importantly, we find that poor on-time performance negatively impacts product markup—proxy for market power. Furthermore, we are able to decompose these markup effects into price and marginal cost effects and evidence suggests that the source of these negative markup effects is primarily driven by negative price responses.
Chapter 27 – Receptors for Parathyroid Hormone (PTH) and PTH-Related Protein

Publisher Summary This chapter deals with the receptors for parathyroid hormone (PTH) particularly the cloned and well characterized PTH1R, and those that are still uncloned but of potential biological significance in overall PTH or PTHrP action, especially the receptor for the carboxyl-terminal portion of PTH for which much recent biochemical data have accumulated. Current data indicate that the PTH receptor interacts with multiple regions of PTH peptide ligands; these contacts establish binding affinity and promote receptor activation. This chapter begins with a description of receptors for PTH, PTHrP, and TIP39: the PTH1R and PTH2R. Following this, it deals with the TIP39 and the PTH2R subtypes. The mechanisms of ligand recognition and activation by PTH receptors are then discussed, affirming that the PTH receptor interacts with multiple regions of PTH peptide ligands; these contacts establish binding affinity and/or promote receptor activation. Furthermore, the study explains the mechanisms of PTH1R function. It also provides an understanding of PTH1R regulation and PTH1R mutations in human disease. Finally, it states that other receptors for PTH and PTHrP include receptors for mid- and carboxyl-terminal portions of PTH and PTHrP and receptors specific for carboxyl-terminal PTH in bone (CPTHR).
From employment optional to “Employment First”: Explaining two cases of state-level disability policy change:

Over the last three decades, the United States has increasingly devolved social policy decisions from the federal to the state level. These changes have resulted in substantial variation in policy ...
A bar and hinge model formulation for structural analysis of curved-crease origami

Abstract In this paper, we present a method for simulating the structural properties of curved-crease origami through the use of a simplified numerical method called the bar and hinge model. We derive stiffness expressions for three deformation behaviors including stretching of the sheet, bending of the sheet, and folding along the creases. The stiffness expressions are based on system parameters that a user knows before analysis, such as the material properties of the sheet and the geometry of the flat fold pattern. We show that the model is capable of capturing folding behavior of curved-crease origami structures accurately by comparing deformed shapes to other theoretical and experimental approximations of the deformations. The model is used to study the structural behavior of a creased annulus sector and an origami fan. These studies demonstrate the versatile capability of the bar and hinge model for exploring the unique mechanical characteristics of curved-crease origami. The simulation codes for curved-crease origami are provided with this paper.
Integrating Electrical Engineering Fundamentals with Instrumentation and Data Acquisition in an Undergraduate Mechanical Engineering Curriculum

The Anonymous University Mechanical Engineering department was awarded a grant from the National Science Foundation to revolutionize its undergraduate program. The goal of the grant is to implement department wide changes that create a focus on doing engineering with engineers and fosters stronger engineering identities in students and faculty. One area of change is the program’s curriculum. This paper describes how the Electrical Engineering Fundamentals course was integrated into the Mechanical Engineering Instrumentation and Data Acquisition (DAQ) course with the goal of creating connections between electrical engineering concepts and applications in mechanical engineering. Design and implementation of this course sequence are presented. Assessment and evaluation methods are also discussed.
The theory of spectral evolution of the GRB prompt emission

We develop the theory of jitter radiation from GRB shocks containing small-scale magnetic fields and propagating at an angle with respect to the line of sight. We demonstrate that the spectra vary considerably: the low-energy photon index, $\alpha$, ranges from 0 to -1 as the apparent viewing angle goes from 0 to $\pi/2$. Thus, we interpret the hard-to-soft evolution and the correlation of $\alpha$ with the photon flux observed in GRBs as a combined effect of temporal variation of the viewing angle and relativistic aberration of an individual thin, instantaneously illuminated shell. The model predicts that about a quarter of time-resolved spectra should have hard spectra, violating the synchrotron $\alpha=-2/3$ line of death. The model also naturally explains why the peak of the distribution of $\alpha$ is at $\alpha\approx-1$. The presence of a low-energy break in the jitter spectrum at oblique angles also explains the appearance of a soft X-ray component in some GRBs and a relatively small number of them. We emphasize that our theory is based solely on the first principles and contains no {\it ad hoc} (phenomenological) assumptions.
On the Magnification of Small Biases in Decision-Making

We analyze a setting in which a board must hire a CEO after exerting effort to learn about the quality of each candidate. Optimal effort is asymmetric, implying asymmetric likelihoods of each candidate being chosen. If the board has a bias in favor of one candidate, it selects an effort allocation that maximizes the likelihood of that candidate being chosen. Surprisingly, this is still often true even when the board's prior is that its preferred candidate is inferior. A glass ceiling can also arise, in which the tendency to hire favored candidates increases as the importance of the position increases.
Vibration of Circular Plates with Edge-Beams

Extensive research in the general area of circular plate vibration has been conducted by numerous researchers, and a compilation of results in the general subject of the vibration of plates has been published by Leissa. The majority of the research has considered the idealized problem in which the plate is characterized by simply supported or clamped boundary conditions. In actuality, plate structures rarely posses simply supported or clamped edges but instead are subjected to conditions somewhat between these two extreme cases. When conditions on the boundary of a plate are changed from those approximating a simple support to a clamped one, small deflections and a more favorable distribution of stress usually result. It is very difficult to actually clamp the edges to take advantage of this fact in design, but a similar stiffening effect can be achieved by providing the plate with an edge-beam, as is shown in this note. By analyzing the coupled problem of the vibrating plate and edge-beam structure simultaneously, an exact solution to the problem is obtained.
Local search for balanced submodular clusterings

In this paper, we consider the problem of producing balanced clusterings with respect to a submodular objective function. Submodular objective functions occur frequently in many applications, and hence this problem is broadly applicable. We show that the results of Patkar and Narayanan [8] can be applied to cases when the submodular function is derived from a bipartite object-feature graph, and moreover, in this case we have an efficient flow based algorithm for finding local improvements. We show the effectiveness of this approach by applying it to the clustering of words in language models.
Refilling of the Earth's plasmasphere

The Earth's ionosphere at mid-latitudes is produced chiefly by solar EUV-induced photo-ionization of the neutral atmosphere at altitudes of 90 to 300–400 kilometers. Such ionized gas, or plasma—entrained by the Earth's (basically bipolar) magnetic field—flows upward along magnetic lines of force, until the plasma gas pressure is equalized along the entire line of force extending from the northern to the southern ionosphere. The plasma region above the ionosphere on such closed magnetic field lines is called the plasmasphere. In fact, the plasmasphere may be considered as an extension of the ionosphere, for there is no clear distinction between them. In the absence of plasma-removal processes, plasma densities may exceed 104 ions/cm3 even at high altitudes of 12,000 kilometers or more.
Normalization of relative and incomplete temporal expressions in clinical narratives

Objective To improve the normalization of relative and incomplete temporal expressions (RI-TIMEXes) in clinical narratives. Methods We analyzed the RI-TIMEXes in temporally annotated corpora and propose two hypotheses regarding the normalization of RI-TIMEXes in the clinical narrative domain: the anchor point hypothesis and the anchor relation hypothesis. We annotated the RI-TIMEXes in three corpora to study the characteristics of RI-TMEXes in different domains. This informed the design of our RI-TIMEX normalization system for the clinical domain, which consists of an anchor point classifier, an anchor relation classifier, and a rule-based RI-TIMEX text span parser. We experimented with different feature sets and performed an error analysis for each system component. Results The annotation confirmed the hypotheses that we can simplify the RI-TIMEXes normalization task using two multi-label classifiers. Our system achieves anchor point classification, anchor relation classification, and rule-based parsing accuracy of 74.68%, 87.71%, and 57.2% (82.09% under relaxed matching criteria), respectively, on the held-out test set of the 2012 i2b2 temporal relation challenge. Discussion Experiments with feature sets reveal some interesting findings, such as: the verbal tense feature does not inform the anchor relation classification in clinical narratives as much as the tokens near the RI-TIMEX. Error analysis showed that underrepresented anchor point and anchor relation classes are difficult to detect. Conclusions We formulate the RI-TIMEX normalization problem as a pair of multi-label classification problems. Considering only RI-TIMEX extraction and normalization, the system achieves statistically significant improvement over the RI-TIMEX results of the best systems in the 2012 i2b2 challenge.
A Method to Quantify Mixing in a Two Component Fluidized Bed

Fluidized bed technology can be used for pyrolysis and gasification of solid fuel particles such as biomass, which is important to industry because of its potential as an alternative for petroleum-based fuels. To efficiently utilize a fluidized bed reactor it is necessary, among other factors, to investigate the mixing and segregation behavior of the fuel particles with the bed material. In order to characterize the material distribution, a technique to visualize the biomass inside a fluidized bed reactor has been developed using X-ray computed tomography (CT) scans. This paper presents an image analysis procedure that can be used to quantify and characterize the local mixing and segregation in a 3D fluidized bed.Copyright © 2010 by ASME
Engineering temperature sensitive live attenuated influenza vaccines from emerging viruses

Abstract The licensed live attenuated influenza A vaccine (LAIV) in the United States is created by making a reassortant containing six internal genes from a cold-adapted master donor strain ( ca A/AA/6/60) and two surface glycoprotein genes from a circulating/emerging strain ( e.g. , A/CA/7/09 for the 2009/2010 H1N1 pandemic). Technologies to rapidly create recombinant viruses directly from patient specimens were used to engineer alternative LAIV candidates that have genomes composed entirely of vRNAs from pandemic or seasonal strains. Multiple mutations involved in the temperature-sensitive ( ts) phenotype of the ca A/AA/6/60 master donor strain were introduced into a 2009 H1N1 pandemic strain rA/New York/1682/2009 (rNY1682-WT) to create rNY1682-TS1, and additional mutations identified in other ts viruses were added to rNY1682-TS1 to create rNY1682-TS2. Both rNY1682-TS1 and rNY1682-TS2 replicated efficiently at 30 °C and 33 °C. However, rNY1682-TS1 was partially restricted, and rNY1682-TS2 was completely restricted at 39 °C. Additionally, engineering the TS1 or TS2 mutations into a distantly related human seasonal H1N1 influenza A virus also resulted pronounced restriction of replication in vitro . Clinical symptoms and virus replication in the lungs of mice showed that although rNY1682-TS2 and the licensed FluMist ® -H1N1pdm LAIV that was used to combat the 2009/2010 pandemic were similarly attenuated, the rNY1682-TS2 was more protective upon challenge with a virulent mutant of pandemic H1N1 virus or a heterologous H1N1 (A/PR/8/1934) virus. This study demonstrates that engineering key temperature sensitive mutations (PB1-K391E, D581G, A661T; PB2-P112S, N265S, N556D, Y658H) into the genomes of influenza A viruses attenuates divergent human virus lineages and provides an alternative strategy for the generation of LAIVs.
Absolute propagation rates in emulsion polymerization I. Butadiene in mutual system

A study has been carried out on the emulsion polymerization of butadiene, using the Mutual Recipe, in an attempt to evaluate the absolute propagation rate, according to the theory of Smith and Ewart, from a determination of the rate of polymerization per particle of latex. It was found, as expected, that the number of particles formed is a function of the temperature of initiation, almost doubling in number for a 10°C. rise in temperature. This number is also a function of the soap charge, being approximately proportional to the square root of the soap concentration. Unlike the case of styrene polymerization, the rate of polymerization per particle was found to be affected by the amount of soap adsorbed on the particle, hence it cannot be considered as representing the true propagation rate for butadiene. However, the rate of polymerization, when calculated per mole of soap present, was found to be a function of temperature only, yielding an activation energy value of ca. 14 kcal.
Community Involvement and Shared Decision Making

What can educators do to improve the public's atti tude about schools? This is the question the writer addresses here. He shows how shared decision making and involvement can create a climate for change.
Decision making and counseling around mammography screening for women aged 80 or older.

BACKGROUND: Despite uncertain benefit, many women over age 80 (oldest-old) receive screening mammography.
Transesterification on imprinted silica

The transesterification reaction of ethyl phenylacetate to hexyl phenylacetate on an “imprinted” silica catalyst of the type first reported by Heilmann and Maier is investigated. In the presence of sulfuric acid co-catalysts, the data obtained here reveal that catalytic activity can be due to phosphorous species leached into solution; no evidence for molecular recognition and catalysis from an imprinted site in the silica is observed. In the absence of co-catalysts, no conclusion regarding the presence of an imprinted site in the silica can be ascertained because of the low level of activity relative to background autocatalysis.
Bundling effects on the intensities of second-order Raman modes in semiconducting single-walled carbon nanotubes

The second-order Raman modes in the range of $380--650\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ were investigated for individually dispersed and aggregated HiPco single-walled carbon nanotubes (SWNTs) using a $700--985\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ tunable laser source. For individually dispersed SWNTs, this Raman region displays relatively weak response from both intermediate frequency modes (IFMs) and the overtones of the radial breathing mode (RBM), with the latter dominating. In contrast, for aggregated SWNTs, the IFMs dominate and gain significant intensity relative to the RBM fundamental. Utilizing the correlation between RBM overtone and RBM fundamental intensity ratio as a function of laser energy, we derived Huang-Rhys factors for several $(n,m)$ nanotube species in both individually dispersed and aggregated states. These values were further used to obtain the corresponding absolute values of the exciton-phonon interaction matrix element for these nanotube species. It is demonstrated that the chiral-angle dependence of exciton-phonon coupling parameters is similar for dispersed and bundled samples. However, we find that bundling results in a decrease in the exciton-phonon coupling for the RBM, while the IFMs display the opposite behavior. These findings are particularly relevant for further clarifying the factors that govern Raman intensities and provide a tool for the selective characterization of various $\mathrm{mod}(n\ensuremath{-}m,3)=2$ $(n,m)$-SWNTs as a function of their aggregation state.
PREDATOR: a resource for database research

This paper describes PREDATOR, a freely available object-relational database system that has been developed at Cornell University. A major motivation in developing PREDATOR was to create a modern code base that could act as a research vehicle for the database community. Pursuing this goal, this paper briefly describes several features of the system that should make it attractive for database research and education.
Comparison of the beliefs and practices of EFNEP clients with staff perceptions of clients

Abstract This study examined how accurately the para-professionals and professionals employed by the Expanded Food and Nutrition Education Program (EFNEP) in New York State perceived the beliefs and practices of their clients. Because paraprofessionals are indigenous workers, they are assumed to have more accurate perceptions of clients than professionals, potentially making them more effective communicators. A series of 36 semistructured interviews with program clients and staff was employed to develop the quantitative measuring instruments used in personal interviews with a purposive sample of 51 clients and as a self-administered questionnaire with all EFNEP staff (43 professionals and 173 paraprofessionals). Results showed that both paraprofessionals and professionals held inaccurate perceptions of their clients in the areas of health, nutrition, resource management, learning, and knowing. EFNEP staff frequently underestimated the ability and self-esteem of clients and the extent to which clients adhered to and considered important the EFNEP objectives. Contrary to expectation, paraprofessionals did not have perceptions of clients that were any more accurate than were those of professionals. These findings suggest that attention to the recruiting, hiring, and training practices of the EFNEP may reduce the disparities between staff perceptions and client responses.
Occupational Performance and the Transition to Powered Mobility: A Pilot Study

OBJECTIVE This quantitative study describes the transition from manual to powered mobility and its influence on occupational performance (organization of daily tasks, assumption of responsibility, roles, interests) and feelings of competence, adaptability, and self-esteem. METHOD The Occupational Performance History Interview (OPHI) was used with a convenience sample of 8 participants with both static and progressive conditions to measure retrospectively changes in occupational performance after the change from a manual wheelchair to a powered mobility device (PMD). The Psychosocial Impact of Assistive Device Scale (PIADS) was used to measure participants' perceptions of the impact of the PMD on their competence, adaptability, and self-esteem. RESULTS A comparison of the pretest and posttest means on the OPHI scores showed a significant improvement in occupational performance (p = .001) after the introduction of PMDs. The PIADS scores showed a positive impact of 2 or greater for 75% of the participants on 19 of 26 items. Scores were similar to scores in a PIADS database of persons with comparable conditions. No significant relationship between occupational performance and psychosocial impact was demonstrated. CONCLUSION Results suggest that the transition to a PMD enhances occupational performance, competence, adaptability, and self-esteem for persons with severe mobility impairments.
Drag force on solar sails due to absorption of solar radiation

We consider a special relativistic effect, known as the Poynting–Robertson effect, on various types of trajectories of solar sails. Since this effect occurs at order vϕ/c, where vϕ is the transversal speed relative to the sun, it can dominate over other special relativistic effects, which occur at order v2/c2. While solar radiation can be used to propel the solar sail, the absorbed portion of it also gives rise to a drag force in the transversal direction. For escape trajectories, this diminishes the cruising velocity, which can have a cumulative effect on the heliocentric distance. For a solar sail directly facing the sun in a bound orbit, the Poynting–Robertson effect decreases its orbital speed, thereby causing it to slowly spiral towards the sun. We also consider this effect for non-Keplerian orbits in which the solar sail is tilted in the azimuthal direction. While in principle the drag force could be counter-balanced by an extremely small tilt of the solar sail in the polar direction, periodic adjustments are more feasible.
Effect of modifications in conformation of protein molecules on structure of mitochondrial membranes

New methods for preparing tissues for electron microscopy were worked out with the aim of limiting as far as possible conformational changes in the protein molecules. The proteins were stabilized by intermolecular cross-linking with glutaraldehyde, dehydrated by short treatment with ethylene glycol, and embedded in Vestopal W or in hydroxypropylmethacrylate. Such treatment appeared to affect the native conformation of proteins less than dehydration by means of air drying with or without previous cross-linking. The mitochondrial membrane elements showed a particulate structure with a range of dimensions of the particles which closely corresponds to that of membrane proteins as judged from their molecular weights. A rectangularly shaped particle measuring 60 × 100 A was frequently observed in the mitochondrial membranes. Intentional denaturation of the tissue by heat or low pH resulted in a membrane structure similar to that observed in conventionally prepared tissues. The results conform with the concept that cellular membranes consist of a two-dimensional array of globular protein molecules and lipoprotein complexes. A continuous light layer of uniform thickness which characterizes the unit membrane structure and which has been interpreted as consisting of a continuous lipid bilayer could be observed only after extensive denaturation of the membrane proteins. The triple-layered unit membrane pattern of membranes, therefore, appears to be the result of extensive denaturation of membrane proteins.
Sense‐making theory and practice: an overview of user interests in knowledge seeking and use

The Sense‐making approach to studying and understanding users and designing systems to serve their needs is reviewed. The approach, developed to focus on user sense making and sense unmaking in the fields of communication and library and information science, is reviewed in terms of its implications for knowledge management. Primary emphasis is placed on moving conceptualizations of users, information and reality from the noun‐based knowledge‐as‐map frameworks of the past to verb‐based frameworks emphasizing diversity, complexity and sense‐making potentials. Knowledge management is described as a field on the precipice of chaos, reaching for a means of emphasizing diversity, complexity and people over centrality, simplicity and technology. Sense making, as an approach, is described as a methodology disciplining the cacophony of diversity and complexity without homogenizing it. Knowledge is reconceptualized from noun to verb.
Mallomonas retrorsa, a new species of silica‐scaled Chrysophyceae with backwards orientated scales

A new species, Mallomonas retrorsa, with a unique siliceous armour, is described from four slightly humic and acidic localities in Connecticut, U.S.A., each low in specific conductance. Cells of the new species have three types of siliceous scales each of which is asymmetric, domeless and arranged with their longitudinal axis parallel to the longitudinal axis of the cell. The scales are positioned such that the posterior rim of each scale faces the apical end of the cell. In addition, the new taxon has an apical whorl of very small, forward projecting paddle-shaped bristles that emerge from the rimmed ends of the apical scales, and an elongated caudal region.
A simplistic plasma dust removal model employing radiation pressure

A simple heuristic model is developed to examine the feasibility of using radiation pressure as a means to transport plasma dust out of the path of the forthcoming electron or photon beam. A slow electromagnetic surface wave coupled to a planar target or substrate exerts the required pressure in the removal process. The model is examined using data and parameters from single-shot radiography experiments. Optimal source requirements are identified for a typical radiography experiment. Source energies and powers are a minimum over an optimum band of frequencies where both conduction and plasma oscillation effects are mutually significant. Above the band of frequencies, dissipative losses in the surface supporting the surface wave increases exponentially with frequency. Below the optimal band, the energy concentration over the plume at the surface structure decreases significantly with frequency, thereby requiring higher source energies/powers for plasma removal.
Two, three and four-dimensional diffusion-limited aggregation models

Abstract Two, three and four-dimensional diffusion-limited aggregation (DLA) models with noise reduction and with growth probabilities proportional to small integer powers (η) of the harmonic measure have been investigated using improved algorithms. The results obtained from these simulations provide the basis for a more decisive test of theoretical results than ordinary DLA simulations alone. Using off-lattice models, effective fractal dimensionalities (D) of about 1.41 and 1.29 were found for η = 2 and 3 respectively for a two dimensional (d=2) embedding space. For d=3, D≌2.13 for η=2 and D≌1.90 for η=3. Similarly, for d = 4, D ≌ 2.97 for η = 2 and D ≌ 2.74 for η = 3. For the noise reduced DLA lattice models our results are consistent with the idea that D⩾d−1 in the asymptotic (s→∞, m→∞) limit where s is the cluster size and m is the noise reduction parameter. However, for d=4, the effective fractal dimensionality is quite close to 3 for m=30.
Stream sediment and nutrient loads in the Tahoe Basin—estimated vs monitored loads for TMDL "crediting"

Total maximum daily load (TMDL) pro- grams utilize pollutant load reductions as the primary strategy to restore adversely affected waters of the USA. Accurate and defensible "crediting" for TMDL reductions of sediment and nutrients requires stream monitoring programs capable of quantitative assess- ment of soil erosivity and the "connectivity" between erosive areas and stream channels across the water- shed. Using continuous (15-min) stream monitoring information from typical alpine, snowmelt-driven wa- tersheds (Ward (2,521 ha), Blackwood (2,886 ha), and Homewood (260 ha, Homewood Mountain Resort— HMR) Creeks) on the west shore of the Lake Tahoe Basin, daily sediment (and nutrient for HMR) loads are determined and compared with those developed from estimated load-flow relationships developed from grab sampling data. Compared to the previously estimated sediment load-discharge relationships, mea- sured curves were slightly below those estimated, though not significantly so at Blackwood and Ward Creeks in the period 1997-2002. Based on average daily flowrates determined from calibrated hydrologic modeling during the period 1994-2004, average daily flowrate frequency distributions per year are deter- mined from which load reduction "crediting" towards TMDL targets can be evaluated. Despite seemingly similar estimated and measured sediment load-flow relationships, annual "estimated" loads exceeded those "measured" by about 40 % for Ward and Blackwood Creeks and over 300 times for HMR Creek. Similarly, though less dramatic, estimated annual nutrient loads at HMR Creek exceeded those measured by 1.7 and 6 times for total nitrogen and total phosphorus, respec- tively. Such results indicate that actual measured load- flow relationships are likely necessary for realistic quantitative and defensible TMDL crediting.
Characterization of PMMA quantum dot composite fabricated by pre- polymerizing method

We characterized a PMMA-quantum-dot (QD) composite fabricated by pre-polymerization of PMMA and dispersing commercially available colloidal semiconductor QDs using photoluminescence and absorption measurements. The QDs are stabilized in rapidly formed oligomer matrices, and the complete polymerization of the PMMA-QD composite is achieved by commonly used polymerization. The properties of the PMMA-QD composite are compared with the QDs in colloidal solution. Photoluminescence vs. temperature was measured from 10K to room temperature and showed a maximum value around 45K.
Glycoprotein VI-mediated platelet fibrinogen receptor activation occurs through calcium-sensitive and PKC-sensitive pathways without a requirement for secreted ADP.

Collagen activates platelets by transducing signals through glycoprotein VI (GPVI). It is not clear whether collagen can directly activate fibrinogen receptors on the adherent platelets without a role for positive feedback agonists. We investigated the contribution of secondary G protein signaling to the mechanism of GPVI-stimulated platelet aggregation using the GPVI-selective agonists, convulxin and collagen-related peptide (CRP) as well as collagen. Adenosine diphosphate (ADP) scavengers or ADP receptor antagonists shifted the concentration-response curve slightly to the right at low concentrations of convulxin, whereas platelet aggregation at higher concentrations of convulxin was unaffected by these agents. ADP receptor antagonists shifted the concentration-response curve of collagen- or CRP-induced platelet aggregation to the right at all the concentrations. Protein kinase C inhibitor, Ro 31-8220, or a calcium chelator 5,5′-dimethyl-BAPTA shifted the concentration-response curve of convulxin-induced platelet aggregation to the right. In addition, pretreatment with both Ro 31-8220 and dimethyl-BAPTA resulted in total inhibition of convulxin-mediated aggregation. Blockade of either the calcium- or protein kinase C–regulated pathway leads to inhibition of fibrinogen receptor activation on platelets adherent to collagen, but inhibition of both pathways leads to abolished fibrinogen receptor activation. We conclude that collagen-induced activation of fibrinogen receptor on adherent platelets through GPVI signaling occurs without any significant role for secreted ADP or thromboxane A2. Furthermore, protein kinase C– and calcium-regulated pathways independently contribute to GPVI-mediated platelet aggregation.
Monte Carlo Simulations of Diblock Copolymer Thin Films Confined between Chemically Heterogeneous Hard Surfaces

Thin films of symmetric diblock copolymers confined between two hard, flat and parallel surfaces have been investigated by means of Monte Carlo simulations on a simple cubic lattice. The upper surface is homogeneous, either neutral or preferential to one of the two blocks, and the lower surface is stripe-patterned, with all the stripes having the same width Ls/2 and alternatively preferring A and B blocks with the same strength of preference. We studied the effects of surface configuration (including surface type, surface pattern period, and surface separation) on the morphology of confined diblock copolymer thin films. Our results show that two conditions are essential for obtaining macroscopically ordered (over micrometers) perpendicular lamellae in the confined films (with film thickness no less than the bulk lamellar period L0): a stripe-patterned substrate with pattern period Ls comparable to L0, which directs the ordering of perpendicular lamellae over a macroscopic scale, and a neutral or weakly p...
Optimal computation of census functions in the postal model

Abstract We consider the problem of computing a census function among n processors in a message-passing system. In this problem, each of the n processors holds one piece of data initially. The goal is to compute an associative and commutative census function h on the n distributed pieces of data and to make the result known to all the processors. To perform the computation, processors send messages to and receive messages from one another in specified communication rounds. To model the communication latencies inherent in many modern message-passing systems, we use the postal model which was recently introduced by Bar-Noy and Kipnis. In this model, a message sent by one processor in a given round is received by another processor only several rounds later. This paper describes an optimal algorithm for the census problem in the postal model. The algorithm requires the least number of communication rounds and minimizes the time spent by each processor in sending and receiving messages.
SIBERIAN BOOK STUDIES

This brief survey notes new publications which contribute to our understanding of the book as it developed in Siberia. Soviet scholars and librarians have a strong tradition of interest in the study of the book «knigovedenie». The rather numerous works which have appeared recently on the vast Siberian area will be useful in understanding regional printing developments in the Soviet Union.
Tertiary Sequence on Northeast Coast of Gulf of Alaska: ABSTRACT

Sedimentary rocks of Tertiary age exceeding 25,000 feet in composite thickness are intermittently exposed in a lowland and foothills belt 300 miles long and 2-40 miles wide on the northeast coast of the Gulf of Alaska. Three major subdivisions of the Tertiary sequence are recognized: (1) interbedded and intertonguing non-marine, brackish-water, and shallow-water marine strata that contain a tropical to warm-temperate flora and marine invertebrate fauna of late Eocene age and include the Stillwater, Kushtaka, and Tokun formations in the Katalla district and an unnamed formation in the Yakataga and Malaspina districts; (2) shallow- to deep-water marine strata that contain a warm-temperate to subtropical invertebrate fauna of Oligocene and early Miocene age and include the l wer part of the Katalla formation in the Katalla district, the Poul Creek formation in the Yakataga district, and the basal part of the exposed Tertiary sequence in the Lituya district; (3) shallow-water marine strata, in part marine tillite, that contain a cool-temperate to sub-boreal invertebrate fauna of late Miocene and Pliocene age and include the upper part of the Katalla formation in the Katalla district, the Yakataga formation in the Yakataga and Malaspina districts, and the upper part of the Tertiary sequence in the Lituya district. Oil seeps and other indications of petroleum are associated mainly with the two lowest subdivisions of the Tertiary sequence. Remains of marine mammals have been found in the upper part of the Poul Creek formation in association with Mollusca and Foraminifera that indicate correlation with the Blakeley formation End_Page 353------------------------------ of Weaver (1912), the Twin River formation of Arnold and Hannibal (1913), and the upper part of the Lincoln formation of Weaver (1912) in Washington. Further collecting and study of these vertebrate remains may aid in determining the position of the Oligocene-Miocene boundary on the Pacific coast of North America. End_of_Article - Last_Page 354------------
Constructing an expert system—software engineering of a different kind

The knowledge engineering and software development tasks involved in constructing software for an expert system are very different from the task of designing an imperative program. Some of the problems in the construction of a rule based expert system include deducing the heuristics of the expert, converting these heuristics into a working taxonomy and rule base, and ordering the rule base so that the system performs efficiently and correctly. We will describe a pictorial method of knowledge representation that we call a “k-tree” and a method of structuring the rule base using what we call “question lattices” that we have found greatly facilitates these tasks.