cssi/SciSciGPT-SciSciNet huggingface dataset:
Photoelectrochemical Methanol Oxidation by TiN Nanoparticles Supported on TiO2

Photocatalytic activity of TiO2-supported TiN and Au nanoparticles towards methanol oxidation is investigated under both visible and UV light excitation. We demonstrate that the TiN/TiO2 photocatalyst performs better than the Au/TiO2 under visible excitation at potentials more positive than 0.1 V vs a Ag/AgCl reference electrode. Under UV excitation, photocurrent enhancement is observed for both the TiN/TiO2 and the Au/TiO2 photocatalysts in the entire potential region from -0.6 to 0.5 V, as compared to pure TiO2. The photocurrent enhancement under UV excitation was assigned to (1) better charge separation in the Au/TiO2 photocatalyst, and (2) generation of highly reactive holes due to interband transitions in TiN and Au nanoparticles.
Healthcare utilization following spinal cord injury: Objective findings from a regional hospital registry.

Objective: The purpose was to describe the prevalence and characteristics of healthcare utilization among individuals with spinal cord injury (SCI) from a Level I trauma center.Design: Retrospective data analysis utilizing a local acute trauma registry for initial hospitalization and merged with the Dallas-Fort Worth Hospital Council registry to obtain subsequent health care utilization in the first post-injury year.Setting: Dallas, TX, USA.Participants: Six hundred and sixty four patients were admitted with an acute traumatic SCI from January 2003 through June 2014 to a Level I trauma center. Fifty five patients that expired during initial hospitalization and 18 patients with unspecified SCI (defined by ICD-9 with no etiology or level of injury specified) were not included in the analysis, leaving a final sample of 591.Outcome Measures: Data included demographic and clinical characteristics, charges, and healthcare utilization.Results: Mean age was 46.1 years (±18.9 years), the majority of patients were ...
Can Nuclear Power Come Back

The nation’s nuclear power industry is in trouble. The number of operating reactors continues to decline, while only one new plant is scheduled to open and it is well behind schedule and 50% over b...
Diffusion Tensor Imaging

Diffusion tensor imaging (DTI), or diffusion tensor magnetic resonance imaging (DT-MRI), is a technique that measures the orientation dependence (i.e., anisotropy) of the diffusion process. This technique relies on diffusion-induced MRI signal loss as a function of diffusion-weighting gradient orientations. With DTI, the diffusion tensor at each spatial location can be characterized, and a series of parameters can be obtained to describe various aspects of the diffusion process in biological tissues. Typical parameters calculated from DTI include apparent diffusion coefficients (ADC), diffusion anisotropy indices, and the principal diffusion direction. These parameters (e.g., fractional anisotropy, or FA) can be used to reveal specific tissue structures, such as white-matter fiber tracts in the brain, and detect their changes during disease progression and regression. Keywords: diffusion; diffusion tensor imaging; anisotropy; fiber tracts
Neurocognition and social cognition training as treatments for violence and aggression in people with severe mental illness

Aggressive and violent behavior, including both verbal and physical aggression, have considerable adverse consequences for people with schizophrenia. There are several potential causes of violent behavior on the part of people with severe mental illness, which include intellectual impairments, cognitive and social-cognitive deficits, skills deficits, substance abuse, antisocial features, and specific psychotic features. This review explores the interventions that have been tested to this date. Computerized Cognitive Training (CCT) or Computerized Social-Cognitive Training (CSCT) have been associated with reductions in violence. Combined CCT and CSCT have been found to improve social cognition and neurocognition, as well as everyday functioning when combined with rehabilitation interventions. These interventions have been shown to reduce violence in schizophrenia patients across multiple environments, including forensic settings. The reductions in violence and aggression have manifested in various ways, including reduced violent thinking and behavior, reduced physical and violent assaults, and reduced disruptive and aggressive behaviors. Effects of cognitive training may be associated with improvements in problem-solving and the increased ability to deploy alternative strategies. The effect of social cognition training on violence reduction appears to be direct, with improvements in violence related to the extent of improvement in social cognition. There are still remaining issues to be addressed in the use of CCT and CSCT, and the benefits should not be overstated; however, the results of these interventions are very promising.
Time-resolved evaluation of compound repositioning predictions on a text-mined knowledge network.

Computational compound repositioning has the potential for identifying new uses for existing drugs, and new algorithms and data source aggregation strategies provide ever-improving results via in silico metrics. However, even with these advances, the number of compounds successfully repositioned via computational screening remains low. New strategies for algorithm evaluation that more accurately reflect the repositioning potential of a compound could provide a better target for future optimizations. Using a text-mined database, we applied a previously described network-based computational repositioning algorithm, yielding strong results via cross-validation, averaging 0.95 AUROC on test-set indications. However, to better approximate a real-world scenario, we built a time-resolved evaluation framework. At various time points, we built networks corresponding to prior knowledge for use as a training set, and then predicted on a test set comprised of indications that were subsequently described. This framework showed a marked reduction in performance, peaking in performance metrics with the 1985 network at an AUROC of .797. Examining performance reductions due to removal of specific types of relationships highlighted the importance of drug-drug and disease-disease similarity metrics. Using data from future timepoints, we demonstrate that further acquisition of these kinds of data may help improve computational results. Evaluating a repositioning algorithm using indications unknown to input network better tunes its ability to find emerging drug indications, rather than finding those which have been randomly withheld. Focusing efforts on improving algorithmic performance in a time-resolved paradigm may further improve computational repositioning predictions.
The Reduction of Ultimate Infarct Size: State of the Art and Goals for the Future

The recognition that coronary artery disease constitutes a major threat to life in most developed nations has led to an intensified effort to identify and control those risk factors associated with premature cardiac mortality and morbidity. There is well documented experimental and clinical evidence to suggest that the extent of myocardial injury and ultimate myocardial cell death resulting from acute myocardial infarction strongly influences ultimate cardiac function and survival. Thus, efforts to minimize the amount of myocardial tissue becoming irreversibly injured in the course of an acute ischemic event have gained intensified interest. The most dramatic and potentially useful approach to the problem has been the restoration of coronary artery blood flow and the return of regional myocardial perfusion through the use of thrombolytic therapy. Coronary artery thrombolysis using streptokinase and perhaps human tissue plasminogen activator, because of its relative simplicity and high degree of success in achieving a lysis of the occlussive thrombus has gained acceptance in many countries of the world as the most useful method of restoring perfusion to the myocardium.
Enhancing the Conductivity of Cell-Laden Alginate Microfibers with Aqueous Graphene for Neural Applications

Microfluidically manufacturing graphene-alginate microfibers create possibilities for encapsulating rat neural cells within conductive 3D tissue scaffolding to enable the creation of real-time 3D sensing arrays with high physiological relavancy. Cells are encapsulated using the biopolymer alginate, which is combined with graphene to create a cell-containing hydrogel with increased electrical conductivity. Resulting novel alginate-graphene microfibers showed a 2.5-fold increase over pure alginate microfibers, but did not show significant differences in size and porosity. Cells encapsulated within the microfibers survive for up to eight days, and maintain approximately 20% live cells over that duration. The biocompatible aqueous graphene suspension used in this investigation was obtained via liquid phase exfoliation of pristine graphite, to create a graphene-alginate pre-hydrogel solution.
Surgical management of pheochromocytoma

Background Pheochromocytoma is one of the most dramatically curable yet potentially devastating tumors encountered. This review is intended to present the current surgical philosophy including practical management details of pheochromocytoma at the Mayo Clinic. Methods Data and recommendations are based primarily on clinical experience obtained from the surgical management of 111 patients with pheochromocytomas over the decade of the 1980s. Results Diagnosis is 98% reliable provided it is considered. Urine metanephrines and VMA plus fractionated catecholamines establish the diagnosis, and nearly all tumors can be localized by computerized tomography, magnetic resonance imaging, or MIBG radionuclide scans. Approximately 10% are bilateral, malignant, extraadrenal in location, and occur in children. Preoperative preparation initially with α-blockade, optionally followed by β-blockade is the standard of care. Conclusions Surgical resection is the only curative treatment for pheochromocytoma and, when attention to detail is maintained throughout the sequence of steps from diagnosis through postoperative care, a potentially lethal catastrophe can be converted to a rewarding experience for both patient and physician.
Quantitative proton radiation therapy dosimetry using the storage phosphor europium-doped potassium chloride

PURPOSE To (a) characterize the fundamental optical and dosimetric properties of the storage phosphor europium-doped potassium chloride for quantitative proton dosimetry, and (b) investigate if its dose radiation response can be described by an analytic radiation transport model. METHODS Cylindrical KCl:Eu2+ dosimeters with dimensions of 6 mm diameter and 1 mm thickness were fabricated in-house. The dosimeters were irradiated using both a Mevion S250 passive scattering proton therapy system and a Varian Clinac iX linear accelerator. Photostimulated luminescence (PSL) emission spectra, excitation spectra, and luminescence lifetimes were measured for both proton and photon irradiations. Dosimetric properties including radiation hardness, dose linearity, signal stabilization, dose rate sensitivity, and energy dependence were studied using a laboratory optical reader after irradiations. The dosimeters were modeled using physical quantities including mass stopping powers in the storage phosphor and water for a given proton beam, and mass energy absorption coefficients and massing stopping powers in detector and water for a given photon beam. RESULTS KCl:Eu2+ exhibited optical emission and stimulation peaks at 421 and 560 nm, respectively, for both proton and photon irradiations, enabling postirradiation readouts using a visible light source while detecting the PSL using a photomultiplier tube. KCl:Eu2+ showed a linear response from 0 to 8 Gy absorbed dose-to-water, a large dynamic range up to 60 Gy, dose-rate independence measured from 83 to 500 MU/min, and a PSL lifetime of <5 ms that is sufficiently short for supporting rapid scanning in a two-dimensional geometry. KCl:Eu2+ was highly reusable with only a slight signal decrease of ~3% at accumulated doses over 100 Gy, which could be managed by a periodic recalibration. The detected PSL signal strength of the dosimeter in the proton field had been calculated accurately to a maximum discrepancy of 2% using known physical quantities along with its prior signal strength as measured in a photon field at the same dose-to-water. This discrepancy might be attributed to an under-response due to linear energy transfer (LET) effect. However, comparisons of depth-dose measurements in a spread-out Bragg peak (SOBP) field with a parallel-plate ionization chamber showed no clear evidence of LET effects. Furthermore, range measurements agreed with ionization chamber measurements to within 1 mm. CONCLUSIONS KCl:Eu2+ showed linear response over a large dynamic range for proton irradiations and reliably reproduced SOBP measurements as measured by ionization chambers. Its relatively low atomic number of 18 and near LET independence make it suited for quantitative proton dosimetry. In addition, its high radiation hardness means that it can be reused numerous times. Any potential measurement artifacts encountered in complex irradiation conditions should be able to be corrected for using known physical quantities.
Intracellular sterol sensing controls intestinal B cell differentiation

Intestinal B cell response is critical for the maintenance of gut homeostasis, yet environmental signals that control B cell metabolism and effector function remain poorly characterized. Here, we show that in Peyer9s patches germinal center (GC) B cells are sensitive to 25-hydorchycholesterol (25-HC), an oxidized metabolite of cholesterol produced by the enzyme cholesterol 25-hydroxylase (CH25H). In mice lacking CH25H, antigen-specific GC B cells show an increased cholesterol metabolic signature and preferentially differentiate in plasma cells (PCs), therefore inducing a stronger intestinal IgA response upon immunization or infection. GC B cells express the sterol sensor SREBP2 and use it to sense 25-HC. Deletion of SREBP2 from GC B cells prevents PC differentiation and forces the maintenance of GC identity. GC localized oxysterol production by follicular dendritic cells is central in dictating GC metabolism and imposing B cell fate. Our findings show that the 25-HC-SREBP2 axis shapes B cell effector function in intestinal lymphoid organs and indicate that dietary cholesterol can instruct local B cell response.
Executive Order 13928 on Blocking Property of Certain Persons Associated with the International Criminal Court

On June 11, 2020, President Donald J. Trump issued Executive Order 13928 Blocking Property of Certain Persons Associated with the International Criminal Court under the authority vested in him by the International Emergency Economic Powers Act (IEEPA) and other federal statutes. Although the Trump Administration had earlier threatened aggressive action against the International Criminal Court (ICC), the issuance of the E.O. followed a ruling by the ICC Appeals Chamber authorizing the Prosecutor to commence an investigation into the situation in Afghanistan, which might implicate U.S. persons. The E.O. declared the ICC's “illegitimate assertion of jurisdiction” over U.S. personnel and the personnel of “certain of its allies” to be “an unusual and extraordinary threat to the national security and foreign policy of the United States” within the meaning of IEEPA. It is a sweeping measure, blocking all property within the United States owned by designated natural or legal person (section 1); barring any contribution or provision of funds, goods, or services to, or for the benefit of, designated persons (section 3), including even the donation of food, clothing, or medicine (section 2). The E.O. also authorized the imposition of certain immigration restrictions, including suspension of entry into the United States of ICC officials and their immediate family members (Section 4).
Pediatric Death by Neurologic Criteria: The Ever-Changing Landscape and the Expanding Role of Palliative Care Professionals.

Abstract Pediatric palliative care providers are especially suited to support families and medical teams facing a potential diagnosis of brain death, or death by neurologic criteria (DNC), when a child suffers a devastating brain injury. To support pediatric palliative care providers’ effectiveness in this role, this article elucidates the clinical determination of DNC and the evolution of the ethical and legal controversies surrounding DNC. Conceptual definitions of death used in the context of DNC have been and continue to be debated amongst academicians, and children's families often have their own concept of death. Increasingly, families have brought legal cases challenging the definition of death, arguing for a right to refuse examination to diagnose DNC, and/or voicing religious objections. We describe these conceptual definitions and legal challenges then explore some potential reasons why families may dispute a determination of DNC. We conclude that working with patients, families, and healthcare providers facing DNC carries inherent and unique challenges suited to intervention by interdisciplinary palliative care teams.
Growth and Photovoltaic Device Application of Cu2BaGe1–xSnxSe4 Films Prepared by Selenization of Sequentially Deposited Precursors

Toward suppressing the formation of anti-site defects and related defect clusters in kesterite Cu2ZnSnS4–xSex (CZTS) absorber films, Cu2–II–IV–X4 (II = Sr, Ba; IV = Ge, Sn; X = S, Se) compounds hav...
Light Interaction with Nitrate Reduction

Light affects assimilation of nitrate via nitrate reductase in many ways. Two prominent examples are: an effect on uptake and movement of nitrate between storage and metabolic pools; and production and distribution of reducing power and generation of carbon skeletons via photosynthesis. Nitrate reductase activity (NRA) correlates more closely with nitrate flux into leaf tissue than leaf nitrate concentration. The possibility that nitrate “flux” through a pool may regulate NRA fits well with the postulation that NO3 − exists in “metabolic” (active) pools, and “storage” (inactive) pools, where only the active pool is available for induction of NRA and for use as a substrate. The existence of “storage” and “metabolic” pools has been demonstrated in tobacco cells (Heimer and Filner, 1971; Ferrari et al., 1973), corn roots (Aslam and Oaks, 1975) and etiolated barley leaves (Aslam et al., 1976).
Involvement of tumor-associated macrophages in colon tumorigenesis

3588 Tumor progression is associated with simultaneous proliferation of cancer cells and the development of tumor stroma that is composed of different types of cells including tumor-associated monocyte/macrophages (TAM). TAMs are observed in human tumors and are though to play a role in tumor vascular development. It is known that tumor derived products are able to block or activate TAM. Following activation TAM may produce a number of factors to promote tumor growth and contribute to vascular development. We have identified a protein of approximate MW 115 kDa on monocytes that binds to carcinoembryonic antigen (CEA). Engagement of the monocyte protein to CEA leads to activation of monocytes to produce cytokines including TNF-alpha ( Biochem Biophys Res Commun , 331:319-323, 2003), and that changes the tumor microenvironment. This has implications in colon tumorigenesis. Since TNF-alpha is implicated in tumor vascularization, we therefore wanted to examine the specificity of CEA binding to the monocyte protein and evaluate its implication in tumor vascular development, which is a prerequisite for tumor development. Binding studies with the purified monocyte protein using immobilized CEA on the surface of a sensor chip suggest that the association of CEA with the monocyte protein was complete within 60 seconds. The binding was specific since monocyte protein binding was not detected on the control surface containing immobilized irrelevant antibody. To examine the relationship between CEA-producing tumors and nature of tumor vasculature, formalin-fixed paraffin embedded colon tumor tissues were stained by immunoperoxidase assay using anti-CEA antibody and anti-CD34 antibody to identify the CEA positive tumors and blood vessels respectively. Blood vessels were counted under a microscope and the number of blood vessels present in randomly selected tumor areas of CEA-positive and CEA-negative tumors was compared. Results suggest that there is significantly higher number of blood vessels present in CEA-positive tumors compared to CEA-negative tumors and the normal colon. The studies suggest that binding of CEA to the monocyte protein is specific and there is a possible correlation between CEA-producing tumors and the presence of increased number of blood vessels in the tumor area. The study is supported by a grant from the National Cancer Institute.
Chapter 4 Electro-Optic Measurement Techniques for Picosecond Materials, Devices, and Integrated Circuits

Publisher Summary This chapter discusses the electro-optic measurement techniques for picosecond materials, devices, and integrated circuits. It describes the fastest of the current optical techniques available, electro-optic sampling. Electro-optic sampling uses electro-optic crystals as the electrical signal sensor. In this system, optical pulses interact directly with the electrical signal via the electro-optic effect. As such, it is an all-optical technique and is one of the simplest ways to exploit the availability of picosecond optical pulses directly as sampling gates. The most significant advantages of the electro-optic measuring techniques are high temporal resolution and flexibility. The applications of electro-optic measuring include the measurement of single devices, such as the 5.4-ps permeable base transistor (PBT); the characterization of transmission lines, the internal probing of GaAs integrated circuits, and InP circuits; the cryogenic measurement of superconducting devices and materials; the external probing of devices and integrated circuits; and even the detection of freely propagating terahertz radiation pulses. The flexibility is attributed to the simple mechanism on which the technique is based that is the electro-optic or Pockels effect, where the optical properties (birefringence) of a crystal change when an electric field is applied across it.
Adaptive Robust Control of Non linear Systems: Effective Use of Information

Abstract This paper considers the adaptive robust control of nonlinear systems in the presence of parametric uncertainties and uncertain nonlinearities. The assumption on the allowable uncertain nonlinearities is relaxed to the extent that uncertain nonlinearities are required to be bounded by some known functions multiplied by unknown but bounded time-varying disturbances only. The approach uses robust feedback to attenuate the effect of uncertainties to achieve a prescribed transient performance and final tracking accuracy. The approach also uses parameter adaptation to reduce model uncertainties to achieve asymptotic tracking in the presence of parametric uncertainties without using switching or infinite-gain feedback. Different design methods are examined and compared.
The Fool's Pedagogy: Jesting for Liminal Learning

The fool emerged as a particularly thought-provoking figure within the literature of the Renaissance, especially the early Renaissance, making its appearance in the novels Don Quixote and Gargantua and Pantagruel, as well as serving as a mouthpiece for the philosophers who introduced Humanism, Erasmus and Nicholas of Cusa. These writers and philosophers relied upon the fool’s role to create meanings out of the ambiguities of the liminality of the early Renaissance. Basically, the world that was flat was becoming round, the truth of theology was being challenged by science, and the dominance of the church was giving way to the nation-state. To assist the people engaged in and living through this transformation, the fool offered a form of communication that encouraged an unbinding of thought and negotiations between incompatible possibilities. Not only did the fool’s rhetoric allow for such a movement in thought, but also encouraged a positioning of the subject (the reader or interlocutor) in such a way that he or she could manage the shift in world conception gracefully.
Electrocatalysis of nitrous oxide reduction: Comparison of several porphyrins and binary “face-to-face” porphyrins

Abstract The activity of several binary or “face-to-face” metalloporphyrins as electrocatalysts for reduction of nitrous oxide have been compared. It is found that a rate enhancement due to binuclear catalysis can be masked by increases in activity attributable to changes in functionality at the porphyrin periphery. By choosing systems were the peripheral substituents are inert hydrocarbons, the “face-to-face” binuclear arrangement is seen to account for at least a thousandfold increase in overall rate.
Incidencia de la carga inicial de pesticidas en fruta sobre los niveles residuales en aceites esenciales cítricos

Resumen es: En Argentina, la produccion citrica es muy importante. Para el control de enfermedades y plagas en las quintas y empaques son utilizados diferentes pesti...
Cognitive skills assessment during robot-assisted surgery: separating the wheat from the chaff.

Objective To investigate the utility of cognitive assessment during robot-assisted surgery (RAS) to define skills in terms of cognitive engagement, mental workload, and mental state; while objectively differentiating between novice and expert surgeons. Subjects and Methods In all, 10 surgeons with varying operative experience were assigned to beginner (BG), combined competent and proficient (CPG), and expert (EG) groups based on the Dreyfus model. The participants performed tasks for basic, intermediate and advanced skills on the da Vinci Surgical System™. Participant performance was assessed using both tool-based and cognitive metrics. Results Tool-based metrics showed significant differences between the BG vs CPG and the BG vs EG, in basic skills. While performing intermediate skills, there were significant differences only on the instrument-to-instrument collisions between the BG vs CPG (2.0 vs 0.2, P = 0.028), and the BG vs EG (2.0 vs 0.1, P = 0.018). There were no significant differences between the CPG and EG for both basic and intermediate skills. However, using cognitive metrics, there were significant differences between all groups for the basic and intermediate skills. In advanced skills, there were no significant differences between the CPG and the EG except time (1116 vs 599.6 s), using tool-based metrics. However, cognitive metrics revealed significant differences between both groups. Conclusion Cognitive assessment of surgeons may aid in defining levels of expertise performing complex surgical tasks once competence is achieved. Cognitive assessment may be used as an adjunct to the traditional methods for skill assessment during RAS.
Myocardial contrast echocardiography: relation between on-line and off-line assessment of myocardial perfusion.

Background: Quantitative assessment of myocardial perfusion by myocafdial contrast echocardiography has been made possible by the use of custom-made off-line video-intensity programs. A standardized program that could be used by all investigators would improve the reproducibility of results and enhance its clinical utility. Methods and Results: The purpose of this study was to determine if the assessment of myocardial perfusion by contrast echocardiography using a new commercially available, quantitative on-line software program correlates with an off-line custom-made video-intensity program previously validated by our laboratory and with radiolabeled microspheres, under various experimental myocardial perfusion conditions. Two of the measured myocardial contrast echocardiographic parameters (peak intensity, area under the time-intensity curve [area]) correlated well among on-line and off-line methods and radiolabeled microspheres, especially when the data were “normalized” by comparing percent change from baseline or a ratio of ischemic to nonischemic myocardium. The third myocardial contrast echocardiographic parameter examined, half-time of the peak intensity on the washout limb of the curve (t1/2), correlated only when the percent change from baseline was compared between the two methods or when the off-line method was compared with radiolabeled microspheres. Conclusion: The results of this investigation add further support to the potential use of myocardial contrast echocardiography to evaluate serial changes in myocardial perfusion. Whether using the off-line or on-line analysis system, it is important that: (1) multiple regions of interest are examined during a single injection: (2) no log compression or postprocessing is performed on the returning ultrasound signal to avoid distortion of the acquired data; and (3) myocardial translation and rotation are corrected with an internal reference system.
Epigenetic and microRNA regulation during osteoarthritis development

Osteoarthritis (OA) is a common degenerative joint disease, the pathological mechanism of which is currently unknown. Genetic alteration is one of the key contributing factors for OA pathology. Recent evidence suggests that epigenetic and microRNA regulation of critical genes may contribute to OA development. In this article, we review the epigenetic and microRNA regulations of genes related to OA development. Potential therapeutic strategies may be developed on the basis of novel findings.
1‐N‐(t‐Butoxycarbonyl)‐1H‐benzotriazole 3‐N‐Oxide

[111615-82-8] C11H13N3O3 (MW 235.27) InChI = 1S/C11H13N3O4/c1-11(2,3)17-10(15)18-14-9-7-5-4-6-8(9)13(16)12-14/h4-7H,1-3H3 InChIKey = FDCDWUSLRGPPLH-UHFFFAOYSA-N (a reagent for protection of amines with the tert-butoxycarbonyl group1) Physical Data: mp 105 °C. Solubility: sol DMF, CH2Cl2, and dioxane, among others. Form Supplied in: the reagent is a white solid; however, it is not commercially available. Handling, Storage, and Precautions: anhydrous conditions are not necessary for reactions, and the reagent can be stored at rt.
Reactive oxygen species as cellular messengers

Reactive oxygen species (ROSs) have recently been found to be important signaling molecules in several cellular responses. Individual species have characteristic reactive properties, yet are easily interconverted, making it difficult to identify the ROSs involved in each response.
Secure latency estimation with treeple

A network latency estimation scheme associates a "position" to every peer in a distributed network such that the latency between any two nodes can be accurately estimated from their positions. Applications for these schemes include efficient overlay construction, compact routing, anonymous route selection, and efficient byzantine agreement. We present a new latency estimation scheme, Treeple. Our scheme is different from existing ones in several aspects: Treeple is provably secure, rather than being able to resist known attacks; positions in Treeple are not Euclidean coordinates and reflect the underlying network topology; finally, positions in Treeple are accurate, stable, and can be assigned to peers not participating in the system.
The Measurement of Effectance Motivation

Three indicators of effectance motivation were devised. A sample of 600 sixth graders was assessed on these measures and IQ scores were collected where available (N = 359). Two of the measures of e...
The effects of preservation on microvascular vein grafts in rats

Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open.
Horizontal Roll Vortices and Crown Fires

Abstract Observational evidence from nine crown fires suggests that horizontal roll vortices are a major mechanism in crown-fire spread. Post-burn aerial photography indicates that unburned tree-crown streets are common with crown fire. Investigation of the understory of these crown streets after two fires showed uncharred tree trunks along a center line. This evidence supports a hypothesis of vortex action causing strong downward motion of air along the streets. Additionally, photographs of two ongoing crown fires show apparent horizontal roll vortices. Discussion also includes laboratory and numerical studies in fluid dynamics that may apply to crown fires.
Applications of continuous time hidden Markov models to the study of misclassified disease outcomes

Disease progression in prospective clinical and epidemiological studies is often conceptualized in terms of transitions between disease states. Analysis of data from such studies can be complicated by a number of factors, including the presence of individuals in various prevalent disease states and with unknown prior disease history, interval censored observations of state transitions and misclassified measurements of disease states. We present an approach where the disease states are modelled as the hidden states of a continuous time hidden Markov model using the imperfect measurements of the disease state as observations. Covariate effects on transitions between disease states are incorporated using a generalized regression framework. Parameter estimation and inference are based on maximum likelihood methods and rely on an EM algorithm. In addition, techniques for model assessment are proposed. Applications to two binary disease outcomes are presented: the oral lesion hairy leukoplakia in a cohort of HIV infected men and cervical human papillomavirus (HPV) infection in a cohort of young women. Estimated transition rates and misclassification probabilities for the hairy leukoplakia data agree well with clinical observations on the persistence and diagnosis of this lesion, lending credibility to the interpretation of hidden states as representing the actual disease states. By contrast, interpretation of the results for the HPV data are more problematic, illustrating that successful application of the hidden Markov model may be highly dependent on the degree to which the assumptions of the model are satisfied.
Three-dimensional laminar incompressible flow in straight polar ducts

Abstract The flow in the entrance region of long ducts of rectangular and polar cross sections is studied using the three-dimensional parabolized Navier-Stokes equations, together with the energy equation, for an incompressible viscous fluid. Numerical solutions are obtained using an alternating-direction implicit technique for the parabolized equations which are elliptic in the cross-plane of the duct, and the calculations march forward in the axial direction. Computations are also made for polar ducts with a rotating outer-radial wall so as to provide meaningful results for a model problem comprising the simplest form of a turbomachinery cascade. The study of this model problem serves to analyze some of the important features of three-dimensional internal viscous flows. Also of interest is the rapidly converging solution of the Neumann problem for the cross-plane variation of pressure for polar ducts.
Oral stereognostic differences between apraxics, dysarthrics, aphasics, and normals

Abstract The present study investigates the pattern of errors displayed by the three differentiable groups of neurologically impaired subjects with expressive disorders of speech: aphasics, apraxics and dysarthrics. All exhibit significant oral stereognostic errors, although as has been shown, some disagreement exists as to the significance of errors made by aphasics. All may be encountered in clinical situations, though differentiation between them may present problems.
Précis of The Grammar of Meaning: Normativity and Semantic Content*

Daniel Dennett once invited us to consider super-Martians who were highly advanced scientifically yet lacked all intentional concepts.' They spoke the language of austere physics and were capable of perceiving and describing the world at the micro-level. If such beings could accurately report happenings in their environment, make predictions, and generally live out their lives wholly within the scientific image, what would they be missing, Dennett wondered, by virtue of lacking intentional concepts? Dennett's answer was that they would miss out on various higher level patterns describable by way of mentalistic and semantic vocabulary. Such an answer, in outline, is fairly standard today. That is, it is fair to say that the general consensus in modem philosophy is that semantic talk-to focus on the species of concern to us-is descriptive of some sort of high level pattern. There is, to be sure, a fair range of disagreement as to what sort of pattern it is. For some, it is a pattern of causal relations between humans, their language, and macroscopic objects; for others, it is purely the functional organization of individual thought, while various philosophers extend the relevant pattern so as to include either relations to external objects, or relations among the people in one's society. Finally, there are those who take semantic discourse to involve the description, in the first instance, of patterns of behavior within a society one is considering from the outside. What all these view have in common is the idea that the claims made using semantic concepts purport to describe. Semantic descriptions are at a radically different ontological level than are the descriptive claims of basic science, but the fundamental sort of speech act involved in ascribing meaning
Origin of photoluminescence signals obtained by picosecond-excitation correlation measurements.

We have developed a theory that explains the spectral distribution and the different time decay behaviors of the signals observed in picosecond excitation-correlation measurements of semiconductor materials. The results display good quantitative agreement with experiments on multiple quantum wells and show that band filling has an important role in determining the characteristics of the correlation signals. Two limit cases are found and mathematically characterized: the non-degenerate regime, where the signals are positive with exponential-like decays, and the degenerate regime, where band filling gives rise to negative signals. It is shown that the technique is a sensitive probe of the carrier dynamics not fully exploited in previous work
A Simplified Method for Administering Vitamin A to Chicks Fed Purified Diets

ABSTRACT The assurance of an adequate intake of vitamin A often poses a problem in experimental poultry nutrition when purified type diets are employed. Although stabilized vitamin A preparations are now available, these products usually contain added antioxidants which preclude their use for certain types of investigations. Thus, in recent experiments in this laboratory it was necessary to find a way of administering vitamin A to chicks fed a purified diet containing no fat or antioxidants (Bieri et al., 1956). Addition of large amounts of dry crystalline vitamin A acetate (30 mg./kg. diet) proved to be unsatisfactory since it was found that sixty percent or more of the vitamin was rapidly destroyed in several days even when the diet was refrigerated (unpublished results). The oral administration of vitamin A in propylene glycol or in aqueous dispersions by dropper had the disadvantage of being too time consuming with large numbers of birds. . . .
Intramolecular chalcogen-tin interactions in [(o-MeEC6H4)CH2]2SnPh(2-n)Cl(n) (E = S, O, CH2; n = 0, 1, 2) and intermolecular chlorine-tin interactions in the meta- and para-methoxy isomers.

Organotin(IV) compounds of the type [(o-MeEC6H4)CH2]2SnPh2−nCln were synthesized, E = O, n = 0 (1), n = 1 (2), and n = 2 (3); E = S, n = 0 (4), n = 1 (5), and n = 2 (6); and E = CH2, n = 0 (7), n =...
Identification of a limited T-cell receptor beta chain variable region repertoire associated with diabetes in the BB rat.

Abstract Diabetes-prone BB rats spontaneously develop type 1 diabetes due to a T-cell-dependent destruction of insulin-producing beta-islet cells. A number of T-cell abnormalities including lymphopenia, poor cell-mediated responsiveness to alloantigen, and an absence of an RT6+ T-cell subset are associated with disease susceptibility. Our previous studies have implicated the thymic antigen-presenting cell in influencing disease potential and responsiveness to alloantigen. Since this cell type is also known to influence T-cell receptor expression in developing thymocytes, we examined the thymic and peripheral T-cell receptor beta chain variable region repertoire in diabetes-prone and diabetes-resistant rats. Our findings indicate that animals susceptible to diabetes induction have a characteristic and limited peripheral beta chain variable region repertoire that differs markedly from that expressed in the thymus.
The role of pH and membrane potential in the reactions of Photosystem II as measured by effects on delayed fluorescence

(1) If DCMU is added to chloroplasts which have been preilluminated (0–8 flashes) the turnover of the water-splitting enzyme is limited to one further transition upon continuous illumination. (2) The intensity of millisecond delayed fluorescence measured in the presence of mediators of cyclic electron transport around Photosystem I and of DCMU added after pre-flashing is stimulated above the level in the presence of DCMU alone and varies according to the number of pre-flashes (Bowes, J.M. and Crofts, A.R. (1978) Z. Naturforsch 33c, 271–275). (3) Separate contributions of the following energetic terms to the induction kinetics and extent of millisecond delayed fluorescence under these conditions have been examined with a view to assessing their involvement in and the mechanism of the stimulation of the emission above the level in dark-adapted chloroplasts in the presence of DCMU: (a) the initial pH of the phase in equilibrium with the water-splitting enzyme; (b) the change in internal pH which occurred when Photosystem I acted as a proton pump; (c) the electrical potential difference across the membrane resulting from rapid charging of the membrane capacitance. (4) It was confirmed that delayed light was stimulated as a result of the interaction of the intrathylakoid pH (3a and b) with the equilibria of the S-states involving proton release according to the model in which this occurs on all except the transition S1 → S2; the stimulation was qualitatively proportional to the number of protons released. (5) There was no marked variation of the membrane potential as a function of the number of pre-flashes.
Epizootiology of the fungus Entomophaga maimaiga, and its impact on gypsy moth populations

Abstract The effect of the fungus, Entomophaga maimaiga, on gypsy moth populations was investigated by assessing the prevalence of disease in caterpillars collected from forest plots and in laboratory-reared, sentinel caterpillars exposed in wire cages in the same plots. The importance of moisture was evaluated by spraying water on portions of two sites four times a day. Large amounts of rainfall in May appeared to be critical for development of the fungus. Under favorable conditions, infection rates averaged 5% or less in May, but reached 40% or more in June. Infective conidia were produced in May, while resting spores became increasingly common within dead cadavers in June. The prevalence of E. maimaiga was slightly higher in forest-collected larvae from sprinkled portions of the sites, and was significantly higher in caged larvae in the irrigated areas. Infection rates also varied between plots, and were correlated with gypsy moth density and tree composition. Using a degree-day model, estimates of daily recruitment and death of fungus-infected caterpillars were obtained. Recruitment in May was not related to precipitation, possibly because of abundant rainfall, but in June recruitment was correlated with the sporadic rainfall that occurred then. Data on recruitment and death were used to construct survival curves for larvae. Only a few to over half the larvae survived the fungus epizootic in different plots.
Comments on “A Nonlinear Model of Internal Tide Transformation on the Australian North West Shelf”

Recently, Holloway et al. (1997) compared simulations and measurements of the nonlinear evolution of internal tides on the Australian North West Shelf. The model they used for simulations was based on a Korteweg–de Vries (KdV) type equation, generalized to include dissipative and range varying effects (henceforth referred to as the gKdV equation). The purpose of this present note is to discuss certain issues concerning their inclusion of dissipation, of which there were two types: 1) turbulent horizontal eddy viscosity, represented by the coefficient n (m2 s21), and 2) quadratic bottom friction, represented by the dimensionless coefficient k. The authors pointed out that, for the value of n they used (n 5 2 3 1024 m2 s21), no apparent effect of eddy viscosity was observed. In considering the question as to what effects would have been produced had the value of n been significantly larger, and in investigating this issue further, we made several observations.
The double-nucleus galaxy IRAS 02580-1136 - A merging system

CCD imaging, infrared photometry, and optical spectroscopy lead to the conclusion that IRAS 02580-1136 consists of two colliding galaxies and is possibly an ongoing merger. Visually, the IRAS source displays two distinct brightness concentrations. These two nuclei, referred to as A and B, have a projected linear separation of 7 kpc and a radial-velocity difference of 180 km/s. Nucleus A belongs to a bulgelike structure and has an optical spectrum typical of a Seyfert 2. It is argued that it harbors a 99 percent dust-obscured low-luminosity Seyfert I source that powers most of the far-infrared radiation. Nucleus B is either a galactic bulge or a low-luminosity elliptical with a heavily reddened compact H II region at its center.
On the significance of 14 and 6 per second positive spikes in the EEG

Bericht uber ein Material von 343 Fallen (380 Kurven) von Patienten mit 14 und 6/sec-positiven Spitzen im EEG. Kinder und Jugendliche uberwogen eindeutig. Die positiven Spitzen waren fast nur im Schlaf oder wahrend Schlafrigkeit nachweisbar. Die wichtigsten diagnostischen Gruppen unserer Patienten waren: Epilepsie (130 Patienten), psychiatrische Storungen (75 Patienten), Schwachsinn mit Zeichen fruhkindlicher Hirnschadigung (47 Patienten), paroxysmale Kopfschmerzen und abdominelle Attacken (46 Patienten). In der psychiatrischen Gruppe war der Prozentsatz reiner 14 und 6-positiver Spitzen mit 50,6% viel hoher als in der Epilepsie-Gruppe (22,5%). Die positiven Spitzen konnen daher nicht als eigentliches Krampfpotential betrachtet werden. Ihre Korrelation mit aggressivpsychopathischen Zustanden scheint von besonderer Bedeutung zu sein. Das gelegentliche Vorkommen positiver Spitzen bei gesunden Personen sollte als „potentielle Abnormitat“ aufgefast werden.