cssi/SciSciGPT-SciSciNet huggingface dataset:
Bayesian Knowledge Fusion

We address the problem of information fusion in uncertain environments. Imagine there are multiple experts building probabilistic models of the same situation and we wish to aggregate the information they provide. There are several problems we may run into by naively merging the information from each. For example, the experts may disagree on the probability of a certain event or they may disagree on the direction of causility between two events (e.g., one thinks A causes B while another thinks B causes A). They may even disagree on the entire structure of dependencies among a set of variables in a probabilistic network. In our proposed solution to this problem, we represent the probabilistic models as Bayesian Knowledge Bases (BKBs) and propose an algorithm called Bayesian knowledge fusion that allows the fusion of multiple BKBs into a single BKB that retains the information from all input sources. This allows for easy aggregation and de-aggregation of information from multiple expert sources and facilitates multi-expert decision making by providing a framework in which all opinions can be preserved and reasoned over.
Mapping virtual objects into real scene

This paper presents a computer vision based framework for mapping virtual objects into a real scene captured by a video camera. Virtual objects are objects contained in a virtual scene stored in a virtual database. This technology has a number of applications including visually-guided robotic navigation, surveillance, military training and operation. The fundamental problem involves several challenging research issues including finding corresponding points between the virtual and the real scene and camera calibration. This paper focuses on our research in selecting reliable control points for the construction of intrinsic and extrinsic camera parameters, which is a vital portion for mapping virtual objects into a real scene.
3-/spl mu/m-band high output erbium-doped fiber lasers

CW and Q-switched fiber lasers emitting in 3-/spl mu/m band have been developed using Er-doped ZBLAN double-clad fibers. CW output power of 3 W and pulse energy of 0.55 mJ are achieved.
The Effects of Grain Boundary Fission Gas on Transient Fuel Behavior

The microstructural response of fast breeder reactor fuel to accident transients has been analyzed. Based on experimental results, fuel response can be classified as either basically brittle or basically ductile in nature. In the analysis, the type of response is assumed to be determined by the behavior of grain boundary fission gas. The transient variables taken into consideration are the temperature, heating rate, the mean gas content per bubble, mean bubble spacing in the grain boundary, and the stresses resolved normal to grain boundaries containing gas bubbles. By calculating the rate at which a grain boundary bubble grows as a sharp crack and comparing it to the rate of bubble growth by mass transport, a criterion is established to predict the characteristic response of a fuel sample to a specified thermal transient. A swelling threshold time is also determined for the case of ductile fuel behavior. Tensile stresses applied to the grain boundary are shown to enhance brittle behavior, and compressive stresses are shown to enhance ductile behavior. When average values of the relevant variables are extracted from a number of fission gas release and direct electric heating experiments and are used in the above calculation, fuel behavior predictions formore » these tests are found to correspond well with the experimental results.« less
Two loop matching conditions on $\bar{\rm MS}$ parton densities

We discuss how the operator product expansion (OPE) can be used to derive asymptotic expressions for certain integrals. This yields operator matrix elements (OME's) which determine the matching conditions for $\bar{\rm MS}$ parton densities across heavy flavour thresholds. Then we construct four and five-flavour densities from a three-flavour set via the AP equation using LO and NLO splitting functions.
Observations of magnetospheric high‐m poloidal waves by ST‐5 satellites in low Earth orbit during geomagnetically quiet times

The poloidal waves with large azimuthal wave numbers (m) in the magnetosphere are known to be generated by drift or drift-bounce resonance with energetic ring current particles, and these waves may play a role in modulating the energetic particles in the inner magnetosphere. When examining the magnetic field data collected by the NASA Space Technology 5 (ST-5) satellites in the low Earth orbit, Le et al. (2011) discovered many wave events with frequencies of 30–200 mHz (in the Pc2 and Pc3 bands), and they proposed that these waves should, in fact, be Doppler-shifted high-m poloidal waves in the magnetosphere with frequencies at only a few millihertz (in the Pc5 band). Using a new method that examines the differences in wave phase detected by the three ST-5 satellites, we confirm that the frequencies in the Earth frame for the poloidal waves observed are mainly between 3 and 5 mHz. Not only were poloidal waves observed frequently by ST-5 in the dayside magnetosphere but they were also occasionally seen in the nightside when the satellites passed through the same L shells. In each wave event, the azimuthal wave number may change with L, but the wave frequency in the Earth frame remains the same. We also find that poloidal waves can last more than 9 h during geomagnetically quiet conditions, suggesting that even a very weak ring current can supply enough energetic particles to excite poloidal waves.
Oblique impacts and peak ring position: Venus and Chicxulub

[1] The circular peak ring of the Chicxulub impact crater is not concentric with the outer rim of the structure, as defined by both gravity and seismic data. Although this has been attributed to an oblique impact, and used to define the direction of impactor approach, different groups have suggested radically different approach azimuths based on the same data sets. We investigate the putative correlation between peak ring offset and impactor azimuth by examining a suite of 19 peak ring craters on Venus, for which the impactor's approach direction is known from their asymmetric external ejecta. We find no statistically significant correlation between peak ring offset and the azimuth of the impactor's approach.
Classification and Disease Prediction Via Mathematical Programming

In this chapter, we present classification models based on mathematical programming approaches. We first provide an overview on various mathematical programming approaches, including linear programming, mixed integer programming, nonlinear programming and support vector machines. Next, we present our effort of novel optimization‐based classification models that are general purpose and suitable for developing predictive rules for large heterogeneous biological and medical data sets. Our predictive model simultaneously incorporates (1) the ability to classify any number of distinct groups; (2) the ability to incorporate heterogeneous types of attributes as input; (3) a high‐dimensional data transformation that eliminates noise and errors in biological data; (4) the ability to incorporate constraints to limit the rate of misclassification, and a reserved‐judgment region that provides a safeguard against over‐training (which tends to lead to high misclassification rates from the resulting predictive rule); and (5) successive multi‐stage classification capability to handle data points placed in the reserved judgment region. To illustrate the power and flexibility of the classification model and solution engine, and its multigroup prediction capability, application of the predictive model to a broad class of biological and medical problems is described. Applications include: the differential diagnosis of the type of erythemato‐squamous diseases; predicting presence/absence of heart disease; genomic analysis and prediction of aberrant CpG island meythlation in human cancer; discriminant analysis of motility and morphology data in human lung carcinoma; prediction of ultrasonic cell disruption for drug delivery; identification of tumor shape and volume in treatment of sarcoma; multistage discriminant analysis of biomarkers for prediction of early atherosclerois; fingerprinting of native and angiogenic microvascular networks for early diagnosis of diabetes, aging, macular degeneracy and tumor metastasis; prediction of protein localization sites; and pattern recognition of satellite images in classification of soil types. In all these applications, the predictive model yields correct classification rates ranging from 80% to 100%. This provides motivation for pursuing its use as a medical diagnostic, monitoring and decision‐making tool.
Rosacea is associated with chronic systemic diseases in a skin severity–dependent manner: Results of a case-control study

Background Rosacea is a common chronic inflammatory dermatosis of unclear origin. It has been associated with systemic comorbidities, but methodical studies addressing this association are lacking. Objective We evaluated: (1) the association between rosacea and systemic comorbidities; and (2) if the severity of rosacea is impacted by comorbidities. Methods This was a case-control study: patients with rosacea were matched (1:1) to rosacea-free control subjects by age, sex, and race. Relative risk estimates were calculated using logistic regression as odds ratios with 95% confidence intervals. Results Among 130 participants (65 patients/65 control subjects), we observed a significant association between rosacea and allergies (airborne, food), respiratory diseases, gastroesophageal reflux disease, other gastrointestinal diseases, hypertension, metabolic and urogenital diseases, and female hormone imbalance. Compared with mild rosacea, moderate to severe rosacea was significantly associated with hyperlipidemia, hypertension, metabolic diseases, cardiovascular diseases, and gastroesophageal reflux disease. Limitations This was a case-control study with moderate sample size. Associated medical conditions were self-reported and could not always be confirmed by medication use and medical records. Conclusions Rosacea is associated with numerous systemic comorbid diseases in a skin severity–dependent manner. Physicians should be aware of these associations to provide comprehensive care to patients with rosacea, especially to those with more severe disease.
Using fuzzy logic for bounded recovery of autonomous agents

The solution to the problem of application-independent fault recovery of autonomous agents requires a specification method for the agent's capacity to act outside of its normal operational limits. This paper presents a recovery method based upon the theory of a fuzzy finite state machine. A fuzzy specification is given for the bounds within which an autonomous agent is capable to recover after an unexpected situation has occurred in its environment. It has been shown that the three main components of the recovery problem: fault detection, fault recovery, and the properties of the actuator/sensor gear of an autonomous agent are interrelated. The suggested method can be implemented either by an application-independent software algorithm, or by fuzzy logic hardware.
Tasking and control of a squad of robotic vehicles

Sandia National Laboratories have developed a squad of robotic vehicles as a test-bed for investigating cooperative control strategies. The squad consists of eight RATLER vehicles and a command station. The RATLERs are medium-sized all-electric vehicles containing a PC104 stack for computation, control, and sensing. Three separate RF channels are used for communications; one for video, one for command and control, and one for differential GPS corrections. Using DGPS and IR proximity sensors, the vehicles are capable of autonomously traversing fairly rough terrain. The control station is a PC running Windows NT. A GUI has been developed that allows a single operator to task and monitor all eight vehicles. To date, the following mission capabilities have been demonstrated: 1. Way-Point Navigation, 2. Formation Following, 3. Perimeter Surveillance, 4. Surround and Diversion, and 5. DGPS Leap Frog. This paper describes the system and briefly outlines each mission capability. The DGPS Leap Frog capability is discussed in more detail. This capability is unique in that it demonstrates how cooperation allows the vehicles to accurately navigate beyond the RF communication range. One vehicle stops and uses its corrected GPS position to re-initialize its receiver to become the DGPS correction station for the other vehicles. Error in position accumulates each time a new vehicle takes over the DGPS duties. The accumulation in error is accurately modeled as a random walk phenomenon. This paper demonstrates how useful accuracy can be maintained beyond the vehicle's range.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Fluorapatite solubility in H2O and H2O–NaCl at 700 to 900 °C and 0.7 to 2.0 GPa

Abstract The solubility of Durango fluorapatite was measured in H 2 O and H 2 O–NaCl at 700–900 °C and 0.7–2.0 GPa in a piston-cylinder apparatus. Solubility was determined by weight loss using a double-capsule method. At all conditions, fluorapatite dissolves incongruently to monazite + fluid, but residual monazite crystals were below weighing detection limits of 0.6 μg. The concentration of fluorapatite dissolved in pure H 2 O is low at all investigated conditions (56 ± 8 to 288 ± 8 ppm by weight), but increases with temperature ( T ) and pressure ( P ). The data are well described by the equation log c ap ° = − 3.56 + .00241 T + 9.17 log ρ H 2 O , where c ap ° is apatite concentration in H 2 O (in ppm), T is in Kelvin, and ρ H 2 O is H 2 O density in g cm − 3 . Fluorapatite solubility was also measured in H 2 O–NaCl fluids at a range of P and T . Results indicate a strong increase in dissolved fluorapatite concentration with rising NaCl mole fraction ( X NaCl ) at all P and T , and X NaCl to near halite saturation. The data were fit to the equation c ap = c ap ° + Ba NaCl 1/2 where c ap is apatite concentration in H 2 O–NaCl (in ppm), a NaCl is NaCl activity calculated from an ideal mixing model for H 2 O–NaCl, and B = (4.4 + 1.1 P 4 )exp(0.0070 T ), with P in GPa, and T in Kelvin. The results differ from previous work in that the newly determined solubilities are ≥ 10 times lower at comparable conditions, increase with P at constant T , and show a strong positive correlation with X NaCl . The discrepancy is attributed to unrecognized growth of new apatite crystals at run conditions in the earlier study. Compared to fluorite, calcite and anhydrite, fluorapatite solubility is significantly lower in H 2 O and H 2 O–NaCl; however, the solubility enhancement by NaCl relative to that in pure H 2 O is similar to anhydrite and much greater than calcite and fluorite. The NaCl enhancement of solubility increases with T but decreases with P . The undetectable weight of monazite requires significant solubility of light rare-earth elements (LREE), likely as chloride complexes, and indicates that metasomatic interaction of brines with apatite-bearing rocks at high metamorphic grades can mobilize substantial LREE.
Acute Stressors and Chronic Response: The Case of Traumatic Stress1

The nature of acute and chronic stress is explored, including analysis of three different ways of categorizing the duration of a stressful episode: the duration of the physical stressor, the duration of threat perception or demand, and the persistence of response. Of particular interest here are situations characterized by brief stressor exposure but long-term threat perception and/ or stress response. Traumatic events are ordinarily very brief but frequently give rise to chronic threat and stubborn response patterns. In many of these cases, distress clearly outlives the event and the “normal” postevent recovery period. Possible mechanisms for such situations are discussed, as are implications for the study of traumatic stress.
Update on stroke risk factors

As medicine moves into the 21st century, with the added pressures of increasing costs and limited resources, successful diminution of the impact of stroke on the population will require shifting our emphasis away from treating end stages of generalized atherosclerosis and other underlying diseases to preventing underlying diseases and stroke. This approach will require more sophisticated and more definitive studies to identify, verify, and explain better the relative importance of known risk factors, the interactions of various risk factors with one another, and the existence of currently unknown or unverified risk factors. In this article, we review the current state of knowledge about certain stroke risk factors in light of new epidemiologic studies conducted in the last decade with emphasis on modifiable risk factors, now and in the future.
Molecular perspective of antigen-mediated mast cell signaling.

Abstract Antigen-mediated cross-linking of the high affinity receptor for IgE (FcϵRI), in the plasma membrane of mast cells, is the first step in the allergic immune response. This event triggers the phosphorylation of specific tyrosines in the cytoplasmic segments of the β and γ subunits of FcϵRI by the Src tyrosine kinase Lyn, which is anchored to the inner leaflet of the plasma membrane. Lyn-induced phosphorylation of FcϵRI occurs in a cholesterol-dependent manner, leading to the hypothesis that cholesterol-rich domains, or “lipid rafts,” may act as functional platforms for IgE receptor signaling. Testing this hypothesis under physiological conditions remains challenging because of the notion that these functional domains are likely transient and much smaller than the diffraction limit of optical microscopy. Here we use ultrafast fluorescence dynamics to investigate the correlation between nanostructural changes in the plasma membrane (labeled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl-indocarbocyanine (diI-C18)) and IgE-FcϵRI cross-linking in adherent RBL mast cells stimulated with multivalent antigen. Time-dependent two-photon fluorescence lifetime imaging microscopy of diI-C18 shows changes in lifetime that agree with the kinetics of stimulated tyrosine phosphorylation of FcϵRI, the first identifiable biochemical step of the allergic response, under the same conditions. In addition, two-photon fluorescence lifetime imaging microscopy of Alexa Fluor 488-labeled IgE indicates that Forster resonance energy transfer occurs with diI-C18 in the plasma membrane. Our live cell studies provide direct evidence for the association of IgE-FcϵRI with specialized cholesterol-rich domains within ∼4-nm proximity and with an energy transfer efficiency of 0.22 ± 0.01 at maximal association during IgE receptor signaling.
Friction and wear of fiber reinforced pps composites

The friction and wear properties of fiber-reinforced polyphenylene sulfide composites were investigated under abrasive and adhesive wear conditions, and an attempt was made to explain the observed data with the friction and wear equations. The measured tribological data were also correlated with the observed microstructures.
Lead us not into Temptation: Race, Rhetoric, and Reality in Southern Populism

(2003). Lead us not into Temptation: Race, Rhetoric, and Reality in Southern Populism. The Historian: Vol. 65, No. 6, pp. 1354-1374.
Photoelectrochemical methods for semiconductor device processing

Abstract The usefulness and capabilities of photoelectrochemical processing of III–V semiconductors is presented. Examples include the etching of small period gratings, the formation of integral lenses, the decomposition of small bandgap semiconductors, the etching of p-type semiconductors, and the photoinitiated deposition of metal. The transport of carriers in the semiconductor and reactivity of the surfaces is discussed.
Characterization of ribonuclease P isolated from rat liver cytosol

Abstract Rat liver ribonuclease P was isolated from a cytosolic fraction and shown to have optimal activity in the presence of 1 m m MgCl 2 and 150–200 m m KCl using Escherichia coli pre-tRNA Tyr as substrate. In cesium sulfate isopycnic density gradients, the enzyme had a buoyant density of 1.36 g/ml, indicating that it is a ribonucleoprotein complex. Analysis of the RNAs in the enzyme sample purified through two successive Cs 2 SO 4 density gradient steps revealed the copurification of two major species of RNA (RRP 1 and RRP 2 ) along with several less abundant RNAs. Rat liver ribonuclease P activity was insensitive to micrococcal nuclease pretreatment. However, the nuclease-treated preparations contained several incompletely degraded RNA species that may have been sufficient to support the ribonuclease P activity. When RNase A was substituted for micrococcal nuclease, the ribonuclease P activity was diminished by greater than 90%, suggesting the requirement for an RNA subunit for activity.
Evolution of sexual systems and sex allocation in plants when growth and reproduction overlap

The common sexual systems in seed plants are hermaphroditism, dioecy, and gynodioecy. Here we attempt to explain this pattern by extending the `classical' resource allocation model for the evolution of sexual systems. First we derive the equilibrium frequencies of all sex morphs and the sex allocations of hermaphrodites as functions of the male and female gain exponents, under the classical assumption that allocation takes place instantaneously from a fixed pool of resources. This analysis reveals two implications of the model that are not widely appreciated: (i) individuals of one sex (males or females) with a decelerating gain function may coexist with hermaphrodites when the gain function for the other sex is accelerating; and (ii) there are large regions of parameter space where the evolutionarily stable sexual system is subdioecy (a high frequency of one sex, with hermaphrodites whose allocation ratios are strongly biased toward the opposite sex function). Then we relax the unrealistic phenological assumption of the classical model and consider models where male allocation precedes female allocation, and where there are tradeoffs between growth and reproduction. When growth and reproduction overlap but there is no tradeoff between them, the predicted ESS sex allocations and sexual systems are identical to those of the classical model (for the same male and female gain exponents). But where there is a tradeoff, the ESS allocation ratios tend to be more female biased than in the classical model, and all three of the common sexual systems (but not androdioecy) can evolve where there is a saturating relation between investment in growth and realised growth.
Functional diversity of AT2 receptor orthologues in closely related species

Functional diversity of AT 2 receptor orthologues in closely related species. Background The most striking feature of life is biodiversity. However, mechanisms of biodiversity remain poorly understood, as most protein orthologues of different species are highly homologous in sequence and identical in function. Interestingly, recent evidence has demonstrated heterogeneity for a G protein-coupled angiotensin II (Ang II) type 2 (AT 2 ) receptor in both ligand binding and induction of arachidonic acid (AA) release. The present study investigated the properties of AT 2 receptors in closely related species. Methods AT 2 receptors cloned from human, rabbit, rat, and mouse were expressed in Chinese hamster ovary cells (CHO-K1), African green monkey kidney cells (COS-1), and human embryonic kidney (HEK)-293 cells and characterized in ligand binding and signal transductions. Critical residues in rabbit AT 2 receptor attributable to heterogeneity were examined using both gain-of-function and loss-of-function approaches with mutagenesis. Results The newly cloned rabbit AT 2 receptor exhibits distinct biochemical and biologic properties compared to its highly homologous orthologues (91% in overall amino acid sequence) of rat, mouse, and human. All these orthologues activate SH2 domain-containing phosphatase-1 (SHP-1) and show similar binding affinities for Ang II and AT 2 -specific ligands CGP42112A and PD123319. However, reducing agent dithiothreitol (DTT) inactivates the rabbit orthologue but potentiates the others in ligand binding, a hallmark of AT 2 versus AT 1 receptor subtypes. Most interestingly, rabbit AT 2 receptor, but not the other orthologues, induces AA release in various cell systems when stimulated by both Ang II and CGP42112A, the peptide antagonist. Mutagenesis studies and sequence analyses further indicate that residues His 106 , Asp 188 , and Thr 293 are responsible for the DTT inactivation and residues Val 209 and Val 249 are partially responsible for AA release. Conclusion These results deny the coexistence of an additional AT 2 subtype in rabbit proximal tubule cells and demonstrate for the first time the presence of functional diversity for closely related Eutherian orthologues of a G protein–coupled receptor (GPCR) that are more than 90% homologous in the amino acid sequence.
Delivery of comprehensive cancer care at Kaiser Permanente

BACKGROUND Kaiser Permanente (KP) is a large health maintenance organization (HMO) operating in 14 states and caring for 8,000,000 members in hundreds of facilities staffed by thousands of physicians and support personnel. Cancer care is provided to these KP members as part of the health care package. METHODS KP insures members for all their health care needs and provides needed services in their own facilities except in rare circumstances. Professional services are provided by physicians of the Permanente Medical Groups, locally governed groups of physicians contractually bound to Kaiser Permanente by capitation agreements. These agreements cover the full range of services for cancer and all other diseases. KP uses evidence-based guidelines to rationalize the provision and delivery of medical care for its members. A large investment in technology has allowed these guidelines to be generally available on local intranets and has facilitated the development of a computerized medical record and linkages to multiple clinical and administrative databases for all providers. Several of the KP regions have strong commitments to research in the public domain and have integrated this effort into the clinical practice of oncology, particularly in clinical trials in cancer treatment and prevention. Research efforts also exist in the areas of cancer epidemiology and outcomes. RESULTS Cancer care is integrated fully into the comprehensive medical care provided the KP member. Health benefits cover the full range of cancer prevention and treatment without distinction by diagnosis. CONCLUSIONS Within the broad range of health care options in the U.S., KP represents a good example of the value of a large HMO to deliver comprehensive general medical and oncologic care. Cancer 1998;82:2076-80. ©; 1998 American Cancer Society.
The role of arousal in memory for conversation.

In the first experimental study of memory for natural conversation, Keenan, MacWhinney, and Mayhew (1977) found that, even after 30 h, subjects had extremely good recognition memory for the exact wording of statements that contained information about a speaker’s “intentions, beliefs, and his relations with the listener.” Such sentences were said to be high in “interactionai content.” One possible interpretation of the results of Keenan et al. is that it is the immediate affective response to an utterance, rather than its interactional content, that increases its memorability. In the present study, the strong relationship between interactional content and memory found by Keenan et al. was replicated. Subjects showed excellent recognition memory for high interactional content statements from a conversation, even after a 72-h interval. However, there was very little relationship between arousal, as determined by subjects’ electrodermal response (EDR), and subsequent memory. Moreover, involvement had its greatest effect not on memory, but on subjects’ arousal as measured by EDR.
Undrained high-pressure and high strain-rate response of dry sand under triaxial loading

Abstract A Kolsky bar was modified to conduct triaxial compression experiments at high rates under the same stress state as in quasi-static conventional triaxial compression tests. Using this experimental technique the triaxial compression response of Quikrete ® ♯ 1961 sand at dry conditions was investigated at varying levels of confining pressure, strain rate, and initial density. The results show that the response of sand has negligible dependencies on strain rate and initial density, but is highly pressure dependent. The ability to impose a triaxial stress state allows the results to form a foundation for constitutive model development.
Symmetric spirals in media with relaxation kinetics and two diffusing species

Abstract We find an approximate solution for the shape and rotation frequency of spirals in excitable media with anti-symmetric kinetics and diffusion in both species. Using singular perturbation theory, we approximate the governing diffusion-reaction system with a free boundary problem and then map this free boundary problem onto a fixed domain problem. The resulting fixed domain problem is viewed as a nonlinear eigenvalue problem which can be solved iteratively using a numerical shooting algorithm. Solutions of the approximate free boundary problem are compared with numerical solutions of the full system of diffusion reaction equations and shown to be in good agreement.
Malaria, Miseria, and underpopulation in Sardinia: The “malaria blocks development” cultural model

Until the late Nineteenth century, endemic malaria was a serious public health problem in Sardinia, as in much of Southern Italy. As the poorest region of the new Italian nation, Sardinia was characterized by poor health, very low population densities, low agricultural productivity, and weak state authority associated with banditry. In this context, however, malaria was singled out as a key underlying problem for the situation of “internal underdevelopment.” This paper describes the Italian scholarly literature about the relationship of malaria and economic productivity as a cultural model that can be labeled as “malaria blocks development” (MBD). Anti‐malaria programs, including the state control of the distribution of quinine as well as land reclamation projects, played a major role in the decrease of malaria mortality in the first part of this century. Based on the logic of the MBD model, the decrease in malaria was expected to decrease an obstacle to “natural processes” of economic development. During...
Impact of class lecture webcasting on attendance and learning

The present study investigated the impact of class lecture webcasts on students’ attendance and learning. The research design employed four data collection methods in two class sections—one with webcast access and another without—of the same course taught by the same instructors. Results indicated the following four major findings. (1) The availability of webcasts negatively impacted student attendance but the availability of other online resources such as PowerPoint slides had a greater negative impact on attendance. (2) Webcast access appeared to nullify the negative effects absenteeism had on student performance. (3) For most performance measures based on lecture content, more webcast viewing was associated with higher performance. (4) Most students in the webcast section reported positive learning experiences and benefits from using webcasts, even though a majority also reported using webcasts for missing a class. In summary, these results collectively suggest that webcasts could have positive effects on students’ learning experiences and performance, even if class attendance does decline.
Substance P and mast cells: preliminary histologic analysis of the human temporomandibular joint.

Abstract Purpose: Neuropeptide-containing nerves can serve as a mechanism for nervous system regulation of host defense responses. Because bacteria associated with reactive arthritis have been identified in the temporomandibular joint (TMJ), this study investigates whether the presence of substance P (SP) neuropeptide-containing nerves and mast cells can be identified in the TMJ. Material And Methods: Posterior bilaminar tissue removed during TMJ surgery from 9 women was evaluated for the presence of neuropeptide-containing nerves by staining with a monoclonal antibody to SP. Staining of the TMJ tissue sections with 0.5% toluidine blue was performed to identify the presence of mast cells. Results: SP-containing nerves and mast cells were identified within the posterior bilaminar tissue associated with the vasculature. Conclusions: The presence of neuropeptide nerves and mast cells within the TMJ has been shown. Mast cell degranulation products and SP release can contribute to TMJ inflammation. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;92:384-9)
Are “bounced check loans” really loans? Theory, evidence and policy

Abstract This research addresses the controversial bank policy of paying – rather than bouncing – overdrawn checks, debits or ATM withdrawals. We argue that it should fall under lending regulations only if consumers use the program to get intentional loans. In contrast, if the program primarily applies to checking account activity then it should fall under checking account regulations. A model of precautionary balance holding and checking account customer data are used to estimate the likelihood of overdrafting. Predicted overdrafts are compared to actual overdrafts to conclude that 79% are explained by the model and thus thought to be mistakes due to the stochastic nature of household expenditures.
Responsiveness of human T lymphocytes to bacterial superantigens presented by cultured rheumatoid arthritis synoviocytes.

OBJECTIVE Type B fibroblastic synoviocytes are abundant in inflamed joints of patients with rheumatoid arthritis (RA), and can secrete cytokines and other mediators of inflammation. The aim of this study was to determine whether cell lines derived from RA type B synoviocytes could also serve as accessory cells for T lymphocyte activation. METHODS Cells from RA synoviocyte lines, with or without preculture in interferon-gamma (IFN gamma), were cultured with purified peripheral blood T cells, in the presence or absence of superantigens or other accessory cell-dependent T cell mitogens. T cell proliferation was measured by thymidine incorporation, and synoviocyte surface markers were analyzed by flow cytometry. RESULTS RA type B synoviocyte lines were potent accessory cells for T cell responses to bacterial superantigens or lectins, and direct cell-cell contact was required. Preculture in IFN gamma augmented synoviocyte expression of major histocompatibility complex (MHC) class II molecules and of ligands for some T cell costimulatory receptors, but synoviocyte accessory cell function was evident even in the absence of IFN gamma. Blocking studies using monoclonal antibodies supported the notion of a role CD2, CD11a/CD18 and MHC class II molecules in synoviocyte-dependent T cell activation. Monoclonal antibodies against IFN gamma, interleukin-1 beta (IL-1 beta), IL-6, IL-8, and tumor necrosis factor alpha failed to block the T cell proliferative responses, but anti-IL-2 was strongly inhibitory. CONCLUSION Cultured RA and type B synoviocytes can perform some of the functions of professional antigen-presenting cells. If such cells have similar properties in vivo, they may be important participants in activation of immune responses, in addition to their previously described synthetic and proinflammatory roles. If RA synovial tissue T cells, like normal peripheral blood T cells, can respond to superantigens presented by synoviocytes, this interaction could be important in the pathogenesis of RA.
Intraoperative Duplex and Functional Popliteal Entrapment Syndrome: Strategy for Effective Treatment

Functional popliteal entrapment syndrome (FPES) was first described by Rignault and colleagues in 1985 (Int. Angiol. 1985;4:341-343). This syndrome results from compression of the popliteal artery by a hypertrophied medial head of the gastrocnemius muscle with no other identifiable anatomical abnormality. The incidence, significance, natural history, and appropriate treatment of this syndrome remain controversial. We present three cases of FPES where intraoperative positional duplex scans guided gastrocnemius muscle resection and confirmed appropriate resection. Additionally, B-mode duplex obtained during one of the cases demonstrated intimal changes consistent with repetitive vessel trauma. All patients had resolution of their claudication and normal physiological testing postoperatively.
Can Natural World Heritage Sites promote development and social harmony

UNESCO designates the areas of biological, geological, and evolutionary importance all over the world as the Natural World Heritage Sites (‘sites’). These sites are all unique, but not equally popular with the tourists. This study quantifies the effect of population, percapita income, and number, area and access on the number of visitors to the sites. The results suggest that good infrastructure for tourism and civil order may be more important than population or income for the number of visitors. The study identifies the policies and institutions that can increase the popularity of the sites. It argues that the sites can promote development, build consensus on conservation, and advance social harmony.
A neural network preestimation filter for bad-data detection and identification in power system state estimation

Popular state estimation techniques in industry are mostly based on the weighted least squares (WLS) method and its derivatives. These estimators usually detect and identify multiple gross measurement errors by repeating a cycle of estimation-detection-elimination. It is rather time consuming for large systems. This paper presents a neural network preestimation filter to identify most forms of gross errors, including conforming bad data, in raw measurements before state estimation rather than afterwards. The proposed neural network model is trained to be a measurement estimator by using the correct measurements of typical system operating states. Once trained, the filter quickly identifies most forms of gross measurement errors simultaneously by comparing the square difference of the raw measurements and their corresponding estimated values with some given thresholds. System observability is maintained by replacing bad data with their reasonably accurate estimates. Using the proposed neural network preestimation filter, the efficiency of present state estimators is greatly improved. Results from several case studies are presented.
Corrections to the Mori-Kawasaki approximation for the high temperature limit of the spin diffusion constant for a magnetic lattice☆

Abstract We report calculations of the leading correction to the Mori-Kawasaki approximation for the high temperature limit of the spin diffusion constant for a magnetic lattice.
The Net and the Self: Working notes for a critical theory of the informational society

Analyse complete de la transformation de la societe et de la culture impliquee dans l'emergence de la societe d'information. Apres avoir repris les theories du post-industrialisme, l'A. montre la reelle nature revolutionnaire des nouvelles technologies d'information en interaction avec la structure sociale : la culture et le symbolique deviennent des forces de production directes, un lien est etabli entre les processus de production, la distribution et la gestion a travers des organisations et des types d'activites, la necessite de la flexibilite apparait, la tension entre globalisation et individualisation s'accentue, les sources de pouvoir ont evolue. La transformation de la condition feminine a entraine une redefinition de la famille, de la sexualite et de la personnalite. La globalisation de l'economie entraine une interdependance de la structure sociale dans le monde entier. Les societes sont faites de reseaux de flux qui operent a quatre niveaux et qui influent sur la structure sociale des reseaux
Arabidopsis ethylene-response gene ETR1: similarity of product to two-component regulators

Ethylene behaves as a hormone in plants, regulating such aspects of growth and development as fruit ripening, flower senescence, and abscission. Ethylene insensitivity is conferred by dominant mutations in the ETR1 gene early in the ethylene signal transduction pathway of Arabidopsis thaliana. The ETR1 gene was cloned by the method of chromosome walking. Each of the four known etr1 mutant alleles contains a missense mutation near the amino terminus of the predicted protein. Although the sequence of the amino-terminal half of the deduced ETR1 protein appears to be novel, the carboxyl-terminal half is similar in sequence to both components of the prokaryotic family of signal transducers known as the two-component systems. Thus, an early step in ethylene signal transduction in plants may involve transfer of phosphate as in prokaryotic two-component systems. The dominant etr1-1 mutant gene conferred ethylene insensitivity to wild-type Arabidopsis plants when introduced by transformation.
Selenosubtilisin's peroxidase activity does not require an intact oxyanion hole

Abstract Replacement of the active site serine in subtilisin with selenocysteine converts the protease to a peroxidase. The contribution of the oxyanion hole to the efficiency of this novel activity has been investigated by substituting Asn155 with glycine via site-directed mutagenesis. Although the side chain amide of Asn155 provides a hydrogen bond that increases the efficiency of the hydrolytic reactions promoted by native subtilisin, it appears to contribute relatively little to the stability of key intermediates or transition states of the selenosubtilisin-catalyzed peroxidase reaction. Instead, the modest changes in kinetic properties resulting from mutation of the selenoenzyme can be explained by subtle alterations in substrate binding at the S1 pocket which perturb the complex equilibria that determine forward progress along the reaction coordinate. Additional modifications of the subtilisin binding site will apparently be necessary to fully exploit the catalytic potential of the oxyanion hole for selenium-dependent redox chemistry.
Visualization and analysis of quasicrystal densities

Several techniques for visualizing and analyzing scatterer densities of quasiperiodic quasicrystals, both in the physical space and in the associated hyperspace, are discussed. In particular, a method for analyzing quasicrystal densities in terms of tilings is introduced and illustrated for the icosahedral Ammann tiling. A specific application to the x‐ray and neutron scattering data of i(Al0.570 Cu 0.108Li0.322) is made. The six‐dimensional hyperspace density of i(Al0.570 Cu 0.108Li0.322) is found to be consistent with the presence of hyperatoms on vertices, edge centers, and body centers of the hypercubic lattice. Some gross features of the hyperatom shapes are suggested. In the physical space, it is shown that densities around some high symmetry points are similar to those in R(Al0.564 Cu 0.116Li0.320) crystal, while around others, they suggest new atomic clusters. The Ammann tiling is found to be a useful template for the structure of i(Al0.570 Cu 0.108Li0.322), with the rhombic dodecahedra as important building units. While several structural models of i(Al0.570 Cu 0.108Li0.322) are generally consistent with the results of the density analysis, some differences are detected. A symmetric decoration of the rhombic dodecahedron, similar to the one found in R(Al0.564 Cu 0.116Li0.320), that is a basis for several structural models, is not consistent with the density analysis. No sign of the pure Al inside the rhombic dodecahedra, nor of the related Al hyperatom at the body center of the hypercrystal, could be detected. © 1996 American Institute of Physics.
Retrograde trafficking of AB5 toxins: mechanisms to therapeutics

Bacterial AB5 toxins are a clinically relevant class of exotoxins that include several well-known members such as Shiga, cholera, and pertussis toxins. Infections with toxin-producing bacteria cause devastating human diseases that affect millions of individuals each year and have no definitive medical treatment. The molecular targets of AB5 toxins reside in the cytosol of infected cells, and the toxins reach the cytosol by trafficking through the retrograde membrane transport pathway that avoids degradative late endosomes and lysosomes. Focusing on Shiga toxin as the archetype member, we review recent advances in understanding the molecular mechanisms involved in the retrograde trafficking of AB5 toxins and highlight how these basic science advances are leading to the development of a promising new therapeutic approach based on inhibiting toxin transport.
SOME NEW METHODS FOR PLANETARY EXPLORATION.

For many centuries the planets of our solar system have been objects of study by astronomers. Before the invention of the telescope, these studies were restricted to an attempt to understand and predict their motion. Telescopes and accurate clocks allowed more precise observations to be made. By the 19th century, minor perturbations of the motions of the planets were being analyzed. By the end of this century, however, astronomers were becoming more interested in stellar and galactic problems, and the group interested in celestial mechanics and planetary observations appeared to be decreasing to a vanishing point in the mid-20th century. Then came the space program, and the possibility of performing experiments on, or at least near, other planets encouraged interest in the solar system to a remarkable degree.
A high-frequency Kerr-effect microscope for bubble devices

A Kerr-effect microscope is described which has been assembled specifically for studies of the dynamic magnetization of the Permalloy elements of magnetic-bubble memory devices at frequencies up to 300 kHz with an illumination spot size of approximately 2 μm. Procedures are described for the setting up and alignment of the microscope and for the calibration of the rotating field.
NASDAQ-Listed American Depository Receipts: What Determines Long-Term Performance?

Cross-sectional regression analysis identifies key variables affecting the initial excess three-year holding period returns of foreign equities traded as American Depository Receipts (ADRs) on the NASDAQ. Results suggest stock market timing effects and changes in the U.S. prime interest rate are the main determinants of the initial three-year holding period returns for 100 ADRs listed from January 1990 through December 2002. The determinants vary once the sample is broken into subsets, comparing ADRs issued before 1998 to those issued afterwards, ADRs issued in emerging markets versus developed markets, and Asia Pacific ADRs versus European and other regional ADRs.
“Contextually” speaking: A survey of pragmatic learning abroad, in class, and online

In order to acquire pragmatic competence, learners must have access to the target language input and opportunities for pragmatic practice. Over the last three decades, research has emerged to specify this fundamental condition of pragmatic learning. Existing studies fall primarily into three main categories: study abroad literature that focuses on students' learning pragmatics in the target language community, formal classroom environment where pragmatics is not the target of instruction, and digitally-mediated contexts in which communication takes place in virtual environments. This paper synthesizes key findings in these three contexts, and compares and contrasts the opportunities and challenges involved in each context, with the overall aim of revealing how each context supports pragmatic learning and development.