cssi/SciSciGPT-SciSciNet huggingface dataset:
Aspirin and the prevention of cardiovascular disease in chronic kidney disease: time to move forward?

Chronic kidney disease (CKD) is a common global public health problem. More than 500 million people worldwide—about 1 in 10 adults—have some form of kidney damage ([1][1]). In the U.S., an estimated 20 million people have CKD, and this number is believed to be increasing exponentially within an
Pesticide protective clothing.

The use of pesticides in the United States has grown 10-fold in the past three decades, and it continues to grow. The dilemma of using pesticides is that “they protect crops from insects, weeds, disease and hunger, but they are also associated with hazards ranging from acute toxicity to cumulative effects such as cancer, birth defects, genetic mutations and sterility” (Boraiko 1980).
Polymer-like Behavior of Inorganic Nanoparticle Chain Aggregates

Studies of the behavior of nanoparticle chain aggregates (NCA) have shown properties similar to those of molecular polymers. Like polymer chains, NCA tend to gather up and become more compact when heated. Under tensile stress, folded chain segments pull out and the NCA elongates. When the tension is relaxed, the chains contract. The stretching of NCA may contribute to the ductility of compacts made from nanoparticles, a subject of current research interest. In a well established technological application, carbon black and pyrogenic silica NCA produce remarkable increases in elastic modulus and tensile strength when added to commercial rubber. This may be due to the mechanical interaction between the polymer chains and NCA. However, basic mechanisms of NCA elasticity differ from those of molecular polymers. The alignment of chain segments when the NCA are subjected to tension probably results from rotation and translation at grain boundaries between neighboring nanocrystals. The elastic properties depend on the van der Waals forces between segments of the chain that fold to minimize surface free energy. Under tension, these segments pull out, but tend to reform when the tension is relaxed. The processes that lead to NCA formation and control the strength of interparticle bonds are briefly reviewed.
Active probing strategies for problem diagnosis in distributed systems

We address the task of problem determination in a distributed system using probes, or test transactions, which gather information about system components. Effective probing requires minimizing the cost of probing while maximizing the diagnostic accuracy of the probe set. We show that pre-planning an optimal probe set is NP-hard and present polynomial-time approximation algorithms that perform well. We then implement an active probing strategy which selects probes dynamically and show that it yields a significant reduction in probe set size in both simulation and a real system environment.
Conceptualizing pain-related stigma in adolescent chronic pain: a literature review and preliminary focus group findings

AbstractIntroduction:Chronic pain in adolescents is a significant medical condition, affecting the physical and psychological well-being of youth and their families. Pain-related stigma is a significant psychosocial factor in adolescents with chronic pain that has been understudied, despite its impl
Acoustic seafloor classification using machine learning and simulations of Helmholtz equations

We discuss numerical methods for inverse problems in high frequency underwater acoustics, aiming to recover detailed characteristics of the seafloor from measured backscatter data generated from SONAR systems. The key to successful inversion is the use of accurate forward modeling capturing the dependence of backscatter on seafloor properties, such as sediment type, roughness, and thickness. Prediction models are often statistical models formed using years of collected ground-truth data or physical models that require costly simulations or unrealistic environmental assumptions. Sophisticated tools are needed to accommodate complicated scenarios, i.e., uncharted seafloor landscapes. To enable a rapid, remote, and accurate seafloor parameter recovery, we propose a combination of machine learning and high fidelity forward modeling and simulation of the physical wave propagation and scattering process. The idea is to partition environments on the order of kilometers in width into much smaller “template” domains, a few meters in width, where the sediment layer can be described using a few parameters. Machine learning is used to train a classifier using a reference library of simulations of Helmholtz equations on the domains. We investigate the potential of multilayer perceptrons and generalized regression in sediment identification using the reference library. [Work supported by NSF and ONR.]
A Case Study in Analog Co-Processing for Solving Stochastic Differential Equations

Stochastic differential equations (SDEs) are an important class of mathematical models for areas such as physics and finance. Usually the model outputs are in the form of statistics of the dependent variables, generated from many solutions of the SDE using different samples of the random variables. Challenges in using existing conventional digital computer architectures for solving SDEs include: rapidly generating the random input variables for the SDE solutions, and having to use numerical integration to solve the differential equations. Recent work by our group has explored using hybrid analog-digital computing to solve differential equations. In the hybrid computing model, we solve differential equations by encoding variables as continuous values, which evolve in continuous time. In this paper we review the prior work, and study using the architecture, in conjunction with analog noise, to solve a canonical SDE, the Black-Scholes SDE.
A binomial Laurent phenomenon algebra associated with the complete graph

In this paper, we find the exchange graph of $$\mathcal {A}({\tau _n})$$ , the rank n binomial Laurent phenomenon algebra associated with the complete graph $$K_n$$ . More specifically, we prove that the exchange graph is isomorphic to that of $$\mathcal {A}(t_n)$$ , a rank n linear Laurent phenomenon algebra associated with the complete graph which is discussed in Lam and Pylyavskyy (Linear Laurent phenomenon algebras, arXiv:1206.2612v2 , 2012).
Getting into character: Narrative form, motivation and Treme’s Harley Watt:

This essay explores the utility of the formalist concept of motivation as a way to interrogate the textual and cultural operation of a TV character, Harley Watt from HBO’s Treme (2010–2013). Peelin...
Principles of Safe Stereotactic Trajectories

Stereotactic planning plays a pivotal role in various neurosurgical procedures including deep brain stimulation (DBS), depth electrode placement, and stereoencephalography (sEEG) for intracranial monitoring in patients with epilepsy, responsive neurostimulation (RNS), laser interstitial thermal therapy (LITT), and biopsies. Presurgical planning is essential to success. This requires a thorough knowledge of clinical presentation, medical history, risk factors, results of preoperative studies, and possible benefits and hazards of surgery. Integration of this knowledge with an understanding of key principles of trajectory planning allows for deep structures of the brain to be approached safely.
MRI in Non-infectious Inflammation and Arthropathies

The non-infectious inflammatory disorders and arthropathies of the spine include several diseases broadly classified as rheumatoid arthritis (RA); the seronegative spondyloarthropathies (SpAs) including ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis (ReA), and enteropathic arthropathy (EnA); the synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) group of syndromes; diffuse idiopathic skeletal hyperostosis (DISH); the crystal-induced arthropathies, including gout, calcium pyrophosphate deposition disease (CPPD), and calcium hydroxyapatite deposition disease (Ca-HADD); and the relatively uncommon disorders of primary synovial and chondrocyte neoplasia: pigmented villonodular synovitis (PVNS) and synovial osteochondromatosis (SOC), respectively.
Cholinergic stimulation improves electrophysiological rate adaptation during pressure overload-induced heart failure in rats.

Analysis of electrophysiology from optical mapping of failing left ventricular myocardium provided insight into the possible therapeutic outcomes of cholinergic stimulation within the left ventricl...
Online lockdown diaries as endurance art.

When the city of Wuhan was severely locked down on January 23, 2020 for 76 days due to the coronavirus outbreak, many residents started writing "lockdown diaries." This article argues these diaries constitute a kind of performance art for their authors, specifically, an 'art of endurance' as described by Shalson (2018). Keeping a diary requires a plan, but the following through of the plan is a contingent process requiring efforts and endurance. The challenges become particularly daunting for authors of online diaries in pandemic times. The article analyzes multiple types of endurance associated with the Wuhan lockdown diarists, showing that in digitally-driven environments, where potential collective responses are a key context, the lockdown diaries of Wuhan, like works of endurance art, engage with meanings that reach far beyond their original experience and context. Their stories of endurance are an allegory of the endurance of the entire city of Wuhan.
The anti-scientists bias: The role of feelings about scientists in COVID-19 attitudes and behaviors.

Across three studies, we investigated who expresses concern for COVID-19, or coronavirus, and engages in behaviors that are consistent with slowing the spread of COVID-19. In Studies 1 and 2 (n = 415, n = 199), those with warmer feelings toward scientists were more concerned and engaged in greater COVID-preventative behaviors, regardless of partisanship. That is, an anti-scientists bias was related to lessened concern and toward less preventive behaviors. Furthermore, those who were the most optimistic about hydroxychloroquine, a purported but unproven treatment against the virus, were less likely to engage in behaviors designed to decrease the spread of COVID-19. In Study 3 (n = 259), asking participants to watch a scientist discuss hydroxychloroquine on Fox News led people to greater endorsement of COVID behaviors. In short, positive feelings toward scientists, rather than political attitudes or knowledge, related to who was concerned and those willing to engage in pandemic reducing behaviors. These behaviors were not immutable and can be changed by scientific out-reach.
Perspectiva europea sobre los riesgos laborales en el ámbito del teletrabajo

Tras la declaracion oficial de la COVID-19 como pandemia por la Organizacion Mundial de la Salud en marzo de 2020, los Estados Miembros de la Union Europea pusieron en marcha una serie de medidas para contener y frenar la expansion del virus en los lugares de trabajo. La naturaleza y el alcance de las restricciones difieren entre Estados y sectores. La crisis de la COVID-19 tambien ha forzado a las empresas a aplicar nuevos procedimientos y practicas en muy poco tiempo o, en algunos casos, a suspender su trabajo y actividades economicas…
Group A Streptococcus-Induced Activation of Human Plasminogen Is Required for Keratinocyte Wound Retraction and Rapid Clot Dissolution.

Invasive outcomes of Group A Streptococcus (GAS) infections that involve damage to skin and other tissues are initiated when these bacteria colonize and disseminate via an open wound to gain access to blood and deeper tissues. Two critical GAS virulence factors, Plasminogen-Associated M-Protein (PAM) and streptokinase (SK), work in concert to bind and activate host human plasminogen (hPg) in order to create a localized proteolytic environment that alters wound-site architecture. Using a wound scratch assay with immortalized epithelial cells, real-time live imaging (RTLI) was used to examine dynamic effects of hPg activation by a PAM-containing skin-trophic GAS isolate (AP53R+S-) during the course of infection. RTLI of these wound models revealed that retraction of the epithelial wound required both GAS and hPg. Isogenic AP53R+S- mutants lacking SK or PAM highly attenuated the time course of retraction of the keratinocyte wound. We also found that relocalization of integrin s1 from the membrane to the cytoplasm occurred during the wound retraction event. We devised a combined in situ-based cellular model of fibrin clot-in epithelial wound to visualize the progress of GAS pathogenesis by RTLI. Our findings showed GAS AP53R+S- hierarchically dissolved the fibrin clot prior to the retraction of keratinocyte monolayers at the leading edge of the wound. Overall, our studies reveal that localized activation of hPg by AP53R+S- via SK and PAM during infection plays a critical role in dissemination of bacteria at the wound site through both rapid dissolution of the fibrin clot and retraction of the keratinocyte wound layer.
The Use of Decision Tree Analysis to Improve LDA Decision Making

In food animal practice, medical decisions are usually made on the basis of economic impact to the dairy, rather than on perceived individual animal value or emotional attachment. A decision routinely made on dairies is what to do with cows that develop left displaced abomasums (LDA). Given the variety of management options available, veterinarians have the potential to make different recommendations depending upon the cow's historical value, parity, current stage oflactation, presence of concurrent disease, level of milk price and relative replacement cost. Decision trees are systematic quantitative tools that may be used to improve the ability to select the best course of action in situations, such as LDA, where the clinical decision is complex and outcomes are uncertain. The objective of this project was to demonstrate the use of a decision tree model as a tool to help select between surgery, roll and toggle or marketing for beef as the most economically appropriate management plan, given an early lactation cow with an LDA.
Material design and characterization of high performance pervious concrete

Abstract Continued urbanization and population growth further the growth of impervious urban areas, leading to concerning adverse environmental and societal impacts. Pervious concrete has remarkable potential to counteract these adverse impacts while providing necessary structural integrity, thus supporting continued urbanization. Broader application of pervious concrete could be achieved through increased raveling resistance and enhanced durability performance. This research emphasizes the development and characterization of high performance pervious concrete aiming at improved mechanical resistance and advanced durability properties. In pursuit of this goal an ultra-high performance cement-based matrix with compressive strengths in excess of 150 MPa (22 ksi) and high durability properties are designed and applied to the mixture design concept of pervious concrete. The research results show that compressive strength and elastic modulus increase by up to 150% and 100%, respectively, without sacrificing the hydraulic conductivity of the concrete. Furthermore, freeze–thaw tests have been carried out to compare the durability performance of conventional pervious concrete with high performance pervious concrete. Based on enhanced mechanical properties as well as improved durability, high performance pervious concrete potentially allows extending the application of pervious concrete and thus carries a vital potential in effectively counteracting the growth of impervious urban areas.
Determining the Sufficiency of Cultural Competence Instruction in Pharmacy School Curriculum.

Objective. To assess the change in the level of cultural competency and knowledge of health disparities among students in the third year of the doctor of pharmacy (PharmD) program at the University of Florida and to explore the demographic correlates. Methods. A cross-sectional survey was conducted in 3 consecutive academic years. Chi-square tests, analysis of variance (ANOVA), and multivariate regression were used for data analysis. Results. Following the inclusion of relevant instruction, there was some increase in knowledge of health disparities and self-awareness, but no significant increase in cultural competency skills. More students reported receiving relevant instruction within the pharmacy school curriculum than outside the curriculum. Conclusion. Current effort to incorporate cultural competence and health disparities instruction into the pharmacy curriculum has met with some success. However, there is a need to establish standards on how much relevant training is required and further explore ways to effectively incorporate it into pharmacy education.
The ν7 vibrational states of C3O2: A least-squares fit of the rigid-bender model to the v7ν7l7 energies and rotational constants

Abstract The rigid-bender model is used to treat the large-amplitude, low-frequency, bending vibration ν 7 of C 3 O 2 . Different parameterizations of the bending potential function are considered, and a simple two-term power series is found to give the best fit. With this parameterization, using a least-squares fit to energies and B values, the ν 7 potential function is determined for the ground state as well as for the states in which ν 2 , ν 3 , ν 4 , ν 6 , 2 ν 6 , ν 1 + ν 3 , ν 1 + ν 4 , ν 2 + ν 3 , and 2 ν 2 + ν 4 are excited. The excitation of other vibrations has in some cases a drastic effect on the ν 7 potential. In the ground state the potential has a 29 cm −1 barrier at the linear position, in ν 1 + ν 3 the barrier increases to 79 cm −1 , while in 2 ν 2 + ν 4 the barrier vanishes. An equilibrium potential is determined by correcting the ground state potential for the effects of zero-point motion of the normal vibrations ν 1 , …, ν 6 . This potential has a 35.6-cm −1 barrier with a minimum at α = 11.14°, where 2α is the angular deviation from linearity. The model accurately predicts the quartic and sextic centrifugal distortion terms for the low-lying v 7 ν 7 l 7 states. Second-order l -type coupling is included in the calculations of the quartic terms. The effects of this coupling, which are most pronounced for the ν 7 ≥ 2 states, adequately explain the negative D term recently reported for the ν 2 + 4 ν 7 0 state.
Filling in the Information Literacy Blank: Developing a Library Orientation for Incoming Community College Students

Library orientation literature suggests a need for hands-on activities to reinforce learning outcomes. Cleveland State Community College Library, while constrained by time, staffing, and renovation, was able to collaborate with the campus orientation committee to develop an interactive, activity-based library orientation session during the college new student orientation.
Understanding ACT-R - an Outsider's Perspective.

The ACT-R theory of cognition developed by John Anderson and colleagues endeavors to explain how humans recall chunks of information and how they solve problems. ACT-R also serves as a theoretical basis for "cognitive tutors", i.e., automatic tutoring systems that help students learn mathematics, computer programming, and other subjects. The official ACT-R definition is distributed across a large body of literature spanning many articles and monographs, and hence it is difficult for an "outsider" to learn the most important aspects of the theory. This paper aims to provide a tutorial to the core components of the ACT-R theory.
Clofarabine plus low-dose cytarabine followed by clofarabine plus low-dose cytarabine alternating with decitabine in acute myeloid leukemia frontline therapy for older patients.

BACKGROUND: Standard therapy for older patients with acute myeloid leukemia (AML) has a poor outcome. The authors have designed a combination of clofarabine plus low-dose cytarabine followed by a prolonged consolidation alternating with decitabine. METHODS: Sixty patients with a median age of 70 years (range, 60-81 years) with newly diagnosed AML were included. They received clofarabine 20 mg/m2 intravenously daily for 5 days plus cytarabine 20 mg subcutaneously twice daily for 10 days. Responding patients continued for up to 17 courses of consolidation therapy including decitabine. RESULTS: Forty of 59 evaluable patients responded (66%). Complete remission rate was 58%. Median relapse-free survival (RFS) was 14.1 (95% confidence interval [CI], 6.9 to not estimable), and median overall survival (OS) was 12.7 months (95% CI, 8.8 to not estimable). Median OS of responding patients (complete response [CR]/CR with platelet count <100 × 109/L) was 24.2 months (95% CI, 17 to not estimable). Compared with a historical group of patients who received clofarabine plus low-dose cytarabine with a shorter consolidation, RFS was not statistically different. Induction mortality was low (7% at 8 weeks) and toxicities manageable. CONCLUSIONS: Clofarabine plus low-dose cytarabine alternating with decitabine in consolidation is active in older patients with newly diagnosed AML. The benefits of a prolonged consolidation remain unproven. Cancer 2012. © 2012 American Cancer Society.
The Importance of Neutral-Neutral Reactions in the Chemistry of CN in Diffuse Clouds

Previous observational studies of the chemistry in diffuse interstellar clouds of diatomic molecules incorporating carbon atoms revealed the importance of ion-molecule reactions. In particular, the measurements of CH and CO are reproduced quite well when ion-molecule reactions form the basis of theoretical chemical models. Although the data for C2 is sparse, the abundance of this molecule most likely also depends on ion-molecule reactions. When the chemistry of CN is scrutinized in the same way, it is found that neutral-neutral reactions play a key role. The CN molecule probably is produced by reactions between C2 and N, with reactions between CH and N of some importance. Thus, we stress, that in addition to the need for precise rate constants for ion-molecule (and radiation association, etc.) reactions, more work on the rate constants for neutral-neutral reactions of astrophysical importance is required.
K+ Channel Expression and Cell Proliferation Are Regulated by Intracellular Sodium and Membrane Depolarization in Oligodendrocyte Progenitor Cells

The effects of a variety of antiproliferative agents on voltage-dependent K+ channel function in cortical oligodendrocyte progenitor (O-2A) cells were studied. Previously, we had shown that glutamate receptor activation reversibly inhibited O-2A cell proliferation stimulated by mitogenic factors and prevented lineage progression by attenuating outward K+ currents in O-2A cells. We now show that the antiproliferative actions of glutamate receptor activation are Ca2+-independent and arise from an increase in intracellular Na+ and subsequent block of outward K+ currents. In support of this mechanism, agents that acted to depolarize O-2A cells or increase intracellular sodium similarly had an antiproliferative effect, attributable at least in part to a reduction in voltage-gated K+ currents. Also, these effects were reversible and Ca2+-independent. Chronic treatment with glutamate agonists was without any long-term effect on K+ current function. Cells cultured in elevated K+, however, demonstrated an upregulation of inward rectifier K+ currents, concomitant with an hyperpolarization of the resting membrane potential. This culture condition therefore promoted a current phenotype typical of pro-oligodendroblasts. Finally, cells chronically treated with the mitotic inhibitor retinoic acid displayed a selective downregulation of outward K+ currents. In conclusion, signals that affect O-2A cell proliferation do so by regulating K+ channel function. These data indicate that the regulation of K+ currents in cells of the oligodendrocyte lineage plays an important role in determining their proliferative potential and demonstrate that O-2A cell K+ current phenotype can be modified by long-term depolarization of the cell membrane.
A NEW RAPID TECHNIQUE FOR SALMONELLA ANTIGEN DETECTION USING A PARTICLE CONCENTRATION FLUORESCENCE IMMUNOASSAY (PCFIA)

A fluorescent assay employing polystyrene beads coated with antibody to a common structural antigen (CSA) of salmonellae has been developed to detect the presence of Salmonella. This sensitive technique is very fast, relatively simple and with further testing may be suitable for screening food products as well as clinical diagnostics. Comparison was made with a commercially available Salmonella antigen capture enzyme immunoassay (EIA). As little as one single colony-forming unit (CFU) could be detected by fluorescence after only 16 h of enrichment. the procedure requires only 1 h to run and uses proportionately smaller volumes of sample and reagents than EIA.
Thiamine-responsive megaloblastic anemia

An 11-year-old Caucasian girl is presented who had a megaloblastic anemia responsive only to thiamine. Other abnormalities included diabetes mellitus, aminoaciduria, and sensorineural deafness. Initially the anemia, refractory to vitamin B 12 and folic acid therapy, responded to administration of a multiple vitamin preparation. Vitamin supplementation was withdrawn followed by a recurrence of anemia 3½ months later. The implicated vitamins were then administered sequentially. A reticulocytosis followed administration of thiamine. Anemia again recurred 4 months after cessation of vitamin supplementation. On this occasion the anemia was corrected by the oral administration of 20 mg. thiamine daily. Thiamine blood levels and activities of 3 thiamine-dependent enzymes of the patient's blood cells were normal, excluding a generalized defect of thiamine metabolism. The patient therefore appeared to have a thiamine-dependent megaloblastic anemia. This represents the first demonstration of a role for this vitamin in DNA metabolism.
Mechanotransduction through growth-factor shedding into the extracellular space

Physical forces elicit biochemical signalling in a diverse array of cells, tissues and organisms, helping to govern fundamental biological processes. Several hypotheses have been advanced that link physical forces to intracellular signalling pathways, but in many cases the molecular mechanisms of mechanotransduction remain elusive. Here we find that compressive stress shrinks the lateral intercellular space surrounding epithelial cells, and triggers cellular signalling via autocrine binding of epidermal growth factor family ligands to the epidermal growth factor receptor. Mathematical analysis predicts that constant rate shedding of autocrine ligands into a collapsing lateral intercellular space leads to increased local ligand concentrations that are sufficient to account for the observed receptor signalling; direct experimental comparison of signalling stimulated by compressive stress versus exogenous soluble ligand supports this prediction. These findings establish a mechanism by which mechanotransduction arises from an autocrine ligand-receptor circuit operating in a dynamically regulated extracellular volume, not requiring induction of force-dependent biochemical processes within the cell or cell membrane.
Progress towards organic single-monolayer rectifiers

Abstract We outline our progress towards Langmuir-Blodgett (LB) monolayers of organic molecules that rectify electrical current (first proposed in 1973 by Aviram). LB monolayers of pyrene-carbamate-bromohydroxyethoxyTCNQ and of dodecyloxyphenyl-carbamate-bromohydroxyethoxyTCNQ have been obtained, but a proper test of their rectification could not be made. Faster and more efficient routes to TCNQ-like monofunctionalized acceptors show considerable promise.
Primary papillary hyperplasia of the gallbladder and cystic and common bile ducts.

Abstract A unique case of primary papillary hyperplasia of the gallbladder and cystic and common bile ducts occurring in a young female without calculi, ulcerative colitis, or primary sclerosing cholangitis is reported. The papillary lesion involved the mucosa of the entire gallbladder and of the cystic and common bile ducts. Histologically, the gallbladder mucosal folds were close to one another and taller than normal. They were lined by normal-appearing colummar cells and pencil-like cells. The papillary projections of the common bile duct were lined only by columnar cells with prominent subnuclear vacuoles. No endocrine cells or cytologic atypia were noted. The differential diagnoses, including secondary hyperplasia, multiple adenomas, and papillomatosis of the gallbladder, are discussed.
Ba15Fe7S25 and Ba3FeS5: Crystal structures, Mössbauer, magnetic, and electrical behavior

Abstract Ba 15 Fe 7 S 25 is prepared by reacting stoichiometric amounts of BaS, Fe, and S in evacuated quartz ampoules while Ba 3 FeS 5 is obtained in a tetrahedral press at 50 kbars and 1000°C. The crystal structure of Ba 15 Fe 7 S 25 has been determined using 4053 independent, nonzero X-ray reflections measured by a counter technique. The compound crystallizes in the orthorhombic system, Pnma , a = 41.91(1) A, b = 9.572(3) A, c = 12.654(3) A, ϱ calc = 4.26 g/cm 3 , z = 4; Ba 3 FeS 5 also crystallizes in Pnma , a = 12.405(1) A, b = 9.516(1) A, c = 8.5212(9)A, ϱ calc = 4.14 g/cm 3 , z = 4. In both compounds, Fe is tetrahedrally coordinated to S, and Ba is in either nine- or eight-fold coordination; a trigonal prism with three rectangular faces capped and a cube. BaS distances are about 3.4 A, and FeS distances are 2.26 A. In Ba 3 FeS 5 , single isolated tetrahedra are present. In Ba 15 Fe 7 S 25 , eight isolated trinuclear units, formed by a central tetrahedron sharing one edge and one corner, respectively, with two terminal tetrahedra and four isolated single tetrahedra are present in the unit cell. The BaS 6 trigonal prisms form infinite columns by sharing the triangular faces. The columns share edges to form distorted hexagonal rings. Within the rings are additional S and Ba ions, and Fe in tetrahedral sites. The main difference between the two structures is the filling of the tetrahedral sites inside the hexagonal rings. The effective paramagnetic moment in Ba 15 Fe 7 S 25 is 5.5 μ B , in good agreement with a value expected from 6Fe 3+ and Fe 2+ from the stoichiometry. The room temperature Mossbauer spectrum shows isomer shifts of 0.2 mm/sec. The data indicate that electron delocalization occurs across the edge-shared tetrahedra so that an effective charge distribution 5Fe 3+ and 2Fe 2.5+ is present. The material has a room temperature electrical resistivity of 10 5 ohm-cm. The effective magnetic moment for Ba 3 FeS 5 is 5.1 μ B as might be expected for Fe 2+ or Fe 4+ . One quadrupole split Mossbauer spectrum is observed with an isomer shift of 0.2 mm/sec, a value usually observed for Fe 3+ . The observations are reconciled by postulating the delocalization of an electron within the tetrahedral configuration. The room temperature electrical resistivity is 10 5 ohm-cm.
Nonlinear Measurements In Multiple Quantum Wells Of Gaas/Algaas Fabricated By Mocvd

We discuss the saturation intensities and saturation densities as a function of well width for the room temperature excitonic absorption resonance of GaAs/A1GaAs multiple quantum well structures grown by metalorganic chemical vapor deposition. The optimum growth temperature is considered. We discuss techniques for calculating absorption coefficients that remove Fabry-Perot effects as well as the effects of carrier diffusion. The difference between pulsed and CW excitation of the mutliple quantum wells is addressed. We discuss the calculation of the nonlinear index of refraction from a discrete set of absorption data. We introduce a new structure (a hetero n-i-p-i) which combines the advantages of multiple quantum wells and doping superlattices.
Microdisk lasers vertically coupled to output waveguides

Semiconductor microdisk resonator lasers vertically coupled to bus waveguides are demonstrated for the first time. These structures have many of the characteristics required for a light source in photonic integrated circuits because they can be coupled to other optical elements (switches, routers, filters, etc.) through common bus lines. A continuous-wave single-mode laser at 1579 nm with a side-mode suppression ratio greater than 30 dB has been achieved for an 8-/spl mu/m-radius microdisk. For larger disks, mode competition between modes near the maximum gain wavelength is observed from the light output-current (L-I) characteristics. Improved heat sink design is required for future devices.
Engineering resilient cyber-physical systems

This panel session paper outlines one of the research thrust areas in the Power System Engineering Research Center's (PSERC) new initiative funded by the US Department of Energy (DOE) to investigate requirements for a systematic transformation of today's electric grid to enable high penetrations of sustainable energy systems. The proposed research under this thrust area looks at the general issue of power grid resiliency. The presentation has three focus areas. First, resiliency with respect to low probably, but high impact events. Second, operational and planning considerations to improve resiliency. Last, consideration of how interactive system control can be used to improve system resiliency.
In VitroFibrinogen Adsorption from Various Dilutions of Human Blood Plasma on Glow Discharge Modified Polyethylene

Abstract Studies have suggested that the adsorption of fibrinogen onto a biomaterial's surface plays an important role in determining a material's blood compatibility. In this study, fibrinogen adsorption from various dilutions of human blood plasma was measured on various radio frequency glow discharge (RFGD) modified surfaces. In addition, the relative binding strength of adsorbed fibrinogen on these surfaces was assessed by subsequent sodium dodecyl sulfate (SDS) elution. More fibrinogen was adsorbed on the hydrophilic surfaces modified by an ammonia plasma, a sulfur dioxide plasma, and an ammonia plasma with propane sultone post treatment than on the untreated polyethylene control. These three hydrophilic surfaces also exhibited higher fibrinogen retention values than the untreated polyethylene control did. The highin vitrofibrinogen adsorption results observed on these hydrophilic surfaces are closely parallel to those obtained previously inex vivocanine shunt experiments. Transient fibrinogen adsorption, also known as the “Vroman Effect,” was not observed on the surfaces modified by the ammonia plasma and the ammonia plasma with propane sultone post treatment. In contrast, maxima in fibrinogen adsorption were noticed on the surface modified by the sulfur dioxide plasma. Despite the variations in surface chemistry, similar fibrinogen adsorption and SDS elution results were noticed on a Silastic control surface and surfaces modified by various plasma polymerized siloxanes.
The many books of nature: Renaissance naturalists and information overload.

Early Renaissance naturalists worked to identify the plans described in ancient sources. But during the middle decades of the sixteenth century, naturalists instead began to describe and name plans unknown to the ancients. They also divided nature much more finely, distinguishing species that their predecessors had lumped together. As a result, they created an information overload. Dictionaries of synonyms and local flora were invented in the early seventeenth century as partial solutions to this problem of information overload.
Social Freedom and Commitment

Much of feminist theory takes issue with traditional, liberal theories of consent and obligation. Though none have proposed abandoning obligation outright, there has been a general shift among feminists towards a responsibility paradigm. Responsibility models acknowledge given relationships and interdependence, and so posit responsibilities as given, regardless of whether they are voluntary. But in theories that take freedom as a principal value, a move from a socially unembedded voluntarism to socially embedded responsibility leaves something missing. Constructive accounts of and prescriptions for freedom must consider the reality of social life; yet acknowledging that relations are given need not require subordinating the role of voluntarism and consent in most relationships. In this paper I offer a commitment framework that seeks to supplant obligation while also reconciling relational given-ness and voluntarism. I propose an analysis of commitment that takes relations as the starting point and then show how the concept can: 1. guide actions 2. account for responsibilities 3. enhance freedom and 4. avoid a large share of coercive forces that are believed as necessary for reinforcing obligation and responsibility fulfillment.
Electron dispersion relations with negative effective masses in quantum wells grown on the cleaved edge of a superlattice

Abstract Engineered energy-wave-vector dispersion relations of either electrons or holes hold great promise for realizing fundamental oscillators at terahertz frequencies if they contain sections with a negative effective mass (NEM) at appropriate energy levels. However, neither bulk semiconductor materials nor quantum wells or quantum wires exhibit such NEM sections in the dispersion relations at favorable energy levels. Therefore, the novel use of a nanostructure is proposed to create an NEM section of electrons at suitable energy levels. This structure utilizes a heterojunction with a quantum well (QW) channel grown perpendicular to a superlattice. At small values of the wave-vector k , the electron wave function Ψ resides mostly in the QW channel and, as k increases, Ψ extends further into the superlattice. This spread of Ψ induces an NEM section in the energy dispersion relation E ( k ). Several combinations of suitable material systems are considered.
The Performance of College Students with and without ADHD: Neuropsychological, Academic, and Psychosocial Functioning

This study examines differences in neuropsychological, academic, psychological and social functioning between college students with attention-deficit/hyperactivity disorder (ADHD) and non-disordered peers. Participants were college students with and without ADHD, attending two universities in the United States. Participants completed questionnaires regarding: executive functioning, psychopathological symptomatology, academic performance, study/organizational skills, social adjustment, emotional expression, and alcohol/substance use. Measures of attention, impulse control, and memory were also obtained. Statistically significant group differences emerged in the areas of executive functions, attention, internalizing and externalizing disorders, emotional expression, academic performance, study/organizational skills, and social adjustment. Implications and suggestions for future research are discussed.
Utilization of new antiepileptic drugs in children

Studies of the newer antiepileptic drugs suggest that they are exciting additions with improved efficacy and a perhaps decreased toxicity in certain types of refractory childhood epilepsy. In some very rare syndromes only anecdotal reports exist and further study is needed. Issues of tolerability, long-term safety in very young children, and effects on learning, behavior and other cognitive functions must be balanced with the possibility of improved efficacy. Additional well-controlled studies taking into account both seizure types and epilepsy syndromes are very much needed in neonates, infants, school aged children and adolescents.
Gut microbiota, tight junction protein expression, intestinal resistance, bacterial translocation and mortality following cholestasis depend on the genetic background of the host

Failure of the intestinal barrier is a characteristic feature of cholestasis. We have previously observed higher mortality in C57BL/6J compared with A/J mice following common bile duct ligation (CBDL). We hypothesized the alteration in gut barrier function following cholestasis would vary by genetic background. Following one week of CBDL, jejunal TEER was significantly reduced in each ligated mouse compared with their sham counterparts; moreover, jejunal TEER was significantly lower in both sham and ligated C57BL/6J compared with sham and ligated A/J mice, respectively. Bacterial translocation to mesenteric lymph nodes was significantly increased in C57BL/6J mice vs. A/J mice. Four of 15 C57BL/6J mice were bacteremic; whereas, none of the 17 A/J mice were. Jejunal IFN-γ mRNA expression was significantly elevated in C57BL/6J compared with A/J mice. Western blot analysis demonstrated a significant decrease in occludin protein expression in C57BL/6J compared with A/J mice following both sham operation and CBDL. Only C57BL/6J mice demonstrated a marked decrease in ZO-1 protein expression following CBDL compared with shams. Pyrosequencing of the 16S rRNA gene in fecal samples showed a dysbiosis only in C57BL/6J mice following CBDL when compared with shams. This study provides evidence of strain differences in gut microbiota, tight junction protein expression, intestinal resistance and bacterial translocation which supports the notion of a genetic predisposition to exaggerated injury following cholestasis.
Parameter estimation of finite mixtures using the EM algorithm and information criteria with application to medical image processing

A method for parameter estimation in image classification or segmentation is studied within the statistical frame of finite mixture distributions. The method models an image as a finite mixture. Each mixture component corresponds to an image class. Each image class is characterized by parameters, such as the intensity mean, the standard deviation, and the number of image pixels in that class. The method uses a maximum likelihood (ML) approach to estimate the parameters of each class and employs information criteria of Akaike (AIC) and/or Schwarz and Rissanen (MDL) to determine the number of classes in the image. In computing the ML solution of the mixture, the method adopts the expectation maximization (EM) algorithm. The initial estimation and convergence of the ML-EM algorithm were studied. The accuracy in determining the number of image classes using AIC and MDL is compared. The MDL criterion performed better than the AIC criterion. A modified MDL showed further improvement. >
Electronic digital counters

Recent advancements in all branches of science have created demands for high-speed counting devices. The development of the electronic digital counters, which are used for many purposes in the large computers, has made such fast computations possible. These counters, which use the binary system, are described in detail in this article.
OUTLIER DETECTION IN TOTAL PHOSPHORUS CONCENTRATION DATA FROM SOUTH FLORIDA RAINFALL1

ABSTRACT: Atmospheric deposition can be a significant source of phosphorus to South Florida's aquatic system. Deposition samples are often contaminated to varying degrees by bird droppings or other foreign materials. This study attempted to use statistical and other methods to detect and remove the outliers in the rain-borne total phosphorus concentration data. Some outliers in the data were identified using field notes derived from visual inspection of the samples. Outlier detection statistics based on a simple linear regression were then used for additional data screening. As a result of these analyses, about 35 percent of the observed values were identified as outlying data which needed to be removed prior to further data analyses. Based on detected outliers in the data from 15 monitoring sites, a lumped cutoff value of 130 4mUg/L was determined. This lumped cutoff value may be useful for further quality control and analyses of the data from the region.
Sexual Assault and Abuse of Children

Testing for sexually transmitted infections (STIs) in children presents a number of problems for the practitioner that are not usually faced when testing adults for the same infections. The identification of an STI in a child can have, in addition to medical implications, serious legal implications. The presence of an STI is often used to support the presence or allegations, or, in some cases, may prompt an investigation of possible abuse. The purpose of this paper is to review the recent data on the epidemiology of child sexual abuse including the epidemiology of major STIs (Neisseria gonorrhoeae, Chlamydia trachomatis, syphilis, herpes simplex virus, Trichomonas vaginalis, and human papillomavirus) and summarize the current recommendations for diagnostic testing in this population.
CVD synthesis and gas permeation properties of thin palladium/alumina membranes

Thin (0.5--5-{micro}m) palladium (Pd) membranes were prepared inside pores or on the surface of mesoporous (pore size 4--6 nm), sol-gel-derived {gamma}-Al{sub 2}O{sub 3} supports by the chemical vapor deposition (CVD) method using palladium acetylacetonate and palladium chloride (together with hydrogen) as Pd precursors. When Pd is deposited in the form of metal plugs inside pores of {gamma}-Al{sub 2}O{sub 3}, He permeance of the composite membranes increases exponentially with temperature, indicating activated diffusion through the microporous metal deposit defects, while only modest permselectivity for H{sub 2} is observed. When Pd is deposited in the form of a metal film on the surface of {gamma}-Al{sub 2}O{sub 3}, He permeance is governed by Knudsen-viscous flow through meso/macroporous metal film defects. The H{sub 2} permeance of different palladium membranes prepared by CVD appears to increase with palladium crystal grain size. The highest H{sub 2} permeance and H{sub 2}:He permselectivity for membranes prepared in this study are about 1.0--2.0 {times} 10{sup {minus}7} mol/m {center_dot} s {center_dot} Pa and 200--300 at 300 C, respectively.
Individual variability in the blood pressure response to intravenous phenylpropanolamine: a pharmacokinetic and pharmacodynamic investigation.

The intersubject variability in blood pressure response to 0.44 mg/kg intravenous phenylpropanolamine (d,l-norephedrine) was studied in 10 normal subjects. A phenylpropanolamine or placebo infusion was administered over 45 minutes on separate days according to a double-blind, balanced protocol. Blood pressure increased by 24 ± 13/16 ± 7 mm Hg (systolic/diastolic, mean ± SD) after the phenylpropanolamine infusion and was statistically different from the placebo infusion response (7 ± 5/8 ± 3 mm Hg). Phenylpropanolamine infusions were terminated early in two subjects (hyper-responders) after 0.31 and 0.23 mg/kg because of excessive increases in blood pressure (52/30 and 34/21 mm Hg, respectively). The hyperresponders had the lowest peak serum phenylpropanolamine concentrations. These data suggest that considerable intersubject variability exists in the blood pressure response to intravenous phenylpropanolamine. A pharmacokinetic basis for the variability in response to racemic phenylpropanolamine was not observed. A relationship did not exist within the group between blood pressure effect and serum concentration but did exist within each subject. Therefore phenylpropanolamine's blood pressure effect in an individual cannot be predicted solely from a serum concentration of racemic drug. Clinical Pharmacology and Therapeutics (1989) 45, 252–259; doi:10.1038/clpt.1989.25