cssi/SciSciGPT-SciSciNet huggingface dataset:
The Primacy of Society and the Failure of Law and Development

Billions of dollars have been spent on law and development (or “rule of law”) projects around the world in the past two decades, focusing on judicial reform, legal training, constitution and code writing, legal transplantation, anti-corruption efforts, and more. In recent overviews, many participants and observers have deemed this effort largely a failure. This essay focuses on surrounding social factors as the primary explanation for this failure. It begins by arguing that “law and development” is a misleading category and should not be seen as a “field.” The essay then examines three themes: legal development, law and capitalism, and the progressive law and development package. The ideas underlying each are elaborated, showing how surrounding social factors interact with each. The essay then argues that law and development projects are often run in a fashion that is flawed from the outset owing to a lack of familiarity with circumstances on the ground. It shows how Western law and development theorists from the right and the left have exported to developing contexts ideas taken from home that have potentially harmful consequences in different settings. The essay concludes that, while efforts to develop the rule of law are essential and must continue, law cannot carry the hopes of economic development or the progressive package. Functional alternatives to law should be supported or created when state legal institutions persistently fail.
Fast spin-echo imaging of the neck: comparison with conventional spin-echo, utility of fat suppression, and evaluation of tissue contrast characteristics.

PURPOSE To determine whether fast spin-echo sequences could replace conventional spin-echo methods in the evaluation of head and neck neoplasms and associated adenopathy and to evaluate differences in tissue contrast characteristics between conventional spin-echo and fast spin-echo examinations of head and neck disease. METHODS Twenty-seven patients with squamous cell carcinoma were imaged on a 1.5-T imager with both conventional spin-echo and fast spin-echo sequences with identical section thickness and position. Twenty-one of the 27 fast spin-echo studies were performed with frequency-selective fat suppression. Three radiologists independently evaluated the images using a five-point scale to compare primary lesion margin definition and conspicuity, lymph node margin definition and conspicuity, gross motion artifact, and flow artifact. Quantitative percent contrast and contrast-to-noise ratios were calculated and compared in 7 cases with fat-suppressed fast spin-echo. RESULTS Fast spin-echo was preferred by all three readers for lesion margin conspicuity and lymph node conspicuity. Gross motion and flow artifact demonstrated trends toward reader preference for fast spin-echo. Quantitative contrast values for fast spin-echo were significantly greater than those for conventional spin-echo. CONCLUSIONS Fast spin-echo with fat suppression can replace conventional spin-echo at a time savings of more than 50% and improves tissue contrast and the conspicuity and definition of margins for primary lesions and lymph nodes. Fat-suppression heterogeneity remains the major limitation of this technique. Thus, careful attention to fat-suppression failure and unwanted water saturation is essential.
Teaching an aerospace engineering design course via virtual worlds: A comparative assessment of learning outcomes

To test the concept of multiuser 3D virtual environments as media to teach semester-long courses, we developed a software prototype called Aeroquest. An aerospace design course-offered to 135 second-year students for university credits in Fall 2009-was divided into two groups: the real-world group attending lectures, physically, in a campus hall and the virtual-world group attending lectures, remotely, in Aeroquest. To date, numerous studies on the educational use of multiuser virtual environments have been reported in the literature. However, among studies on virtual-world-based courses, our investigation was one of the firsts to employ learning outcomes (rather than affective states) that were objectively measured (rather than subjectively reported) against a control group. We found that the virtual-world group achieved the performance benchmark, defined by the exam score of the real-world group, within a 95% confidence interval, suggesting the virtual worlds' untapped potential as a teaching platform in early engineering courses-especially for distance education.
Relation of Phanerozoic stable isotope excursions to climate, bacterial metabolism, and major extinctions.

Conspicuous global stable carbon isotope excursions that are recorded in marine sedimentary rocks of Phanerozoic age and were associated with major extinctions have generally paralleled global stable oxygen isotope excursions. All of these phenomena are therefore likely to share a common origin through global climate change. Exceptional patterns for carbon isotope excursions resulted from massive carbon burial during warm intervals of widespread marine anoxic conditions. The many carbon isotope excursions that parallel those for oxygen isotopes can to a large degree be accounted for by the Q10 pattern of respiration for bacteria: As temperature changed along continental margins, where ∼90% of marine carbon burial occurs today, rates of remineralization of isotopically light carbon must have changed exponentially. This would have reduced organic carbon burial during global warming and increased it during global cooling. Also contributing to the δ13C excursions have been release and uptake of methane by clathrates, the positive correlation between temperature and degree of fractionation of carbon isotopes by phytoplankton at temperatures below ∼15°, and increased phytoplankton productivity during “icehouse” conditions. The Q10 pattern for bacteria and climate-related changes in clathrate volume represent positive feedbacks for climate change.
Non-Blocking Synchronization and Memory Management

Non-blocking data structures offer high availability and strong progress guarantees. They are guaranteed to be available regardless of thread scheduling, including thread termination and indefinite delay. This guarantee is most useful in cases such as sharing between threads and signal handlers, systems where processes could be terminated asynchronously, and soft real-time applications such as media players.The inherent characteristics of non-blocking algorithms pose intricate problems that need to be solved to achieve the desired progress guarantees. Many of such problems are related to memory management, including dynamic memory allocation, the determination of the safety of reclaiming dynamic memory blocks, the ABA problem, and bounding memory use of non-blocking algorithms. This talk presents an overview of non-blocking synchronization and the memory management problems that arise in non-blocking algorithms and their solutions.
The role of alcohol use and depression in intimate partner violence among Black and Hispanic patients in an urban emergency department

Objectives: The primary objective of this study was to assess the role of alcohol use and depression in intimate partner violence (IPV) victimization and perpetration among Blacks and Hispanics in an underserved urban emergency department population. Methods: This cross-sectional study surveyed male and female patients presenting to an urban emergency department. The outcome measures were physical or sexual IPV victimization and perpetration in the previous 12 months. The independent predictors included demographic variables, alcohol and drug use, and depressive symptoms. Logistic regression analyses calculated the adjusted odds ratio (AOR) and 95% confidence interval (CI) for predictors of IPV victimization and perpetration in separate models. Results: The prevalence of IPV victimization among Blacks and Hispanics were similar (14% and 10%, respectively) but blacks were nearly twice as likely to report IPV perpetration (17% vs. 9%, respectively).Predictors of IPV perpetration were Black race, married or ...
Parasites of shore crabs in the genus Hemigrapsus (Decapoda: Brachyura: Varunidae) and their status in crabs geographically displaced: a review

Two brachyurans of the varunid genus Hemigrapsus from the northwestern Pacific Ocean have invaded coastal regions of the north Atlantic – Hemigrapsus takanoi (sibling species of Hemigrapsus penicillatus) and Hemigrapsus sanguineus in Europe and the latter in the USA. Parasites are known from these crabs in their native habitats, but except for an undescribed larval nematode, none has been found in those examined from their new locations. These parasites include metacercariae of eight species of microphallid trematode, the rhizocephalan barnacles Polyascus polygenea, Sacculina nigra and Sacculina senta, and the obligate gut-inhabiting mesomycetozoan Enteromyces callianassae (potential parasite). The following have been identified in four of the other eight Pacific crabs within the genus (Hemigrapsus nudus and Hemigrapsus oregonensis, northern hemisphere; Hemigrapsus crenulatus and Hemigrapsus sexdentatus, southern hemisphere), none of which have been geographically displaced: metacercariae of two microphal...
Simulation of Blood Flow in Deformable Arteries Using Subject-Specific Geometry and Variable Vessel Wall Properties

Previous efforts to simulate blood flow in patient-specific models either assumed rigid vessel walls or deformable walls with constant mechanical property [1]. We have developed a new workflow to enable blood flow and vessel dynamics simulations using subject-specific geometry and variable wall properties. The geometric model construction is based on 3D segmentation and geometric processing which greatly reduce human labor and increase the objectivity of the model. Variable wall properties are assigned to the model based on combining centerline-based and surface-based methods. This new approach was successfully applied to simulate blood flow and wall dynamics in models with abdominal, thoracic, and cerebral aneurysms.Copyright © 2009 by ASME
Exponential and Continued Fractions

Abstract We show that the simple continued fractions for the analogues of (ae2/n+b)/(ce2/n+d) in function fields, with the usual exponential replaced by the exponential forFq[t] have very interesting patterns. These are quite different from their classical counterparts. We also show some continued fraction expansions coming from function field analogues of hypergeometric functions
Chronic Stress Impairs Prefrontal Cortex-Dependent Response Inhibition and Spatial Working Memory

Chronic stress leads to neurochemical and structural alterations in the prefrontal cortex (PFC) that correspond to deficits in PFC-mediated behaviors. The present study examined the effects of chronic restraint stress on response inhibition (using a response-withholding task, the fixed-minimum interval schedule of reinforcement, or FMI), and working memory (using a radial arm water maze, RAWM). Adult male Sprague-Dawley rats were first trained on the RAWM and subsequently trained on FMI. After acquisition of FMI, rats were assigned to a restraint stress (6h/d/28d in wire mesh restrainers) or control condition. Immediately after chronic stress, rats were tested on FMI and subsequently on RAWM. FMI results suggest that chronic stress reduces response inhibition capacity and motivation to initiate the task on selective conditions when sucrose reward was not obtained on the preceding trial. RAWM results suggest that chronic stress produces transient deficits in working memory without altering previously consolidated reference memory. Behavioral measures from FMI failed to correlate with metrics from RAWM except for one in which changes in FMI timing imprecision negatively correlated with changes in RAWM working memory errors for the controls, a finding that was not observed following chronic stress. Fisher's r-to-z transformation revealed no significant differences between control and stress groups with correlation coefficients. These findings are the first to show that chronic stress impairs both response inhibition and working memory, two behaviors that have never been directly compared within the same animals after chronic stress, using FMI, an appetitive task, and RAWM, a nonappetitive task.
Myosin-V motility: these levers were made for walking.

Abstract Myosin-Va, a processive actin-based motor thought to be involved in organelle transport, now stands ready to join myosin-II (from muscle) as one of the most highly characterized members of the myosin superfamily. Recent reports from the laboratories of Goldman and colleagues and Selvin and colleagues have provided unprecedented, high-resolution views of the structural changes that take place while this motor moves along its track. Taken together, the new results indicate that myosin-Va tilts its light chain binding domains to ‘walk' along actin in a hand-over-hand fashion.
Identification of axial ligands of cytochrome c552 from Nitrosomonas europaea

Cytochrome c552 from Nitrosomonas europaea was analyzed by visible, EPR and MCD spectroscopies. The visible and MCD data show that histidine and methionine are the axial ligands to the heme iron of the ferric protein. The EPR spectrum of the cytochrome shows an atypical highly axial low spin (HALS) type signal with g-values that make it difficult to identify the axial ligands. These results reinforce the value of near-infrared MCD spectroscopy for assigning ligands in ferric heme systems and point out the difficulties in using only EPR spectroscopy for the same purpose. The description of another c-cytochrome exhibiting a HALS-type EPR signal will eventually be helpful in explaining the physical basis for this unusual signal.
Halogenated nucleic acids: effects of 5-fluorouracil on the conformation and properties of a polyribonucleotide and its constituents.

The conformational properties of 5-fluorouracil derivatives are compared to uracil derivatives. FUrd, 5′-FUMP, and poly(FU) are studied as a function of pH and temperature by 19F- and 1H-nmr spectroscopy, and the corresponding uracil derivatives by 1H-nmr spectroscopy. FUrd exhibits no significant conformational changes with solution pH (5–10). In contrast, at low pH (6–7) 5′-FUMP and 5′-UMP show similar conformational features, while at high pH (9) 5′-FUMP shows significant conformational alterations. Also, poly(U) and poly(FU) are conformationally similar at low pH, but increasing pH induces changes in poly(FU). These changes are observed in the backbone [γ(C4′-C5′)], furanose, and furanose-base conformations. The apparent pKa of N3-H ionization of the FUra base is determined by 1H- and 19F-nmr to range from 7.5 to 8.2 [FUrd < 5′-FUMP < 5′-FUDP < poly(FU)]. These observations are interpreted as a result of electrostatic interactions generated between the ionized phosphate group and the negatively charged base moiety as the pH is raised. The interaction properties of poly(FU) with ApA are studied by 1H- and 19F-nmr spectroscopy, and these properties compared to those published for poly(U). Poly(FU) forms a complex with ApA inducing upfield 1H-shifts in both components, and downfield 19F- shifts in poly(FU). The base stoichiometry of the complex for poly(U)·ApA is 2U:1A at various U/A ratios. In contrast, the base stoichiometry of the poly(FU)·ApA complex appears to be dependent on the FU/A ratio. At high FU/A ratio, the complex is 2FU:1A, and as the FU/A ratio approaches unity the complex becomes 1FU:1A.
Alternative model for emplacement of the Papuan ophiolite, Papua New Guinea

The mechanism for emplacing large ophiolite bodies is poorly understood. One of the larger ophiolites known is exposed along the northeast coast of the Papuan peninsula, Papua New Guinea. A new model for the geologic development of the peninsula, based on a reinterpretation of the nature of the Owen Stanley metamorphic belt, is proposed. Owen Stanley rocks are considered to be sediments mainly deposited on oceanic crust and accreted to an easterly dipping island arc as the underlying crust was subducted. Emplacement of the ophiolite occurred in two stages. Uplift began when lighter material was accreted under the ophiolite during the island-arc stage, and further uplift of the ophiolite to its present position occurred when the island arc collided with and partially subducted semicontinental material.
Finite amplitude oscillations of viscoelastic fluids

Abstract Finite amplitude oscillatory shear experiments are used to study the mechanical behavior of viscoelastic materials. Four rheological relations are derived which can be used to determine both linear and nonlinear rheological properties of simple fluids from data obtained using large amplitude oscillatory experiments. Two consistency conditions are derived for a fluid which obeys the K-BKZ constitutive equation, and these relations are used in conjunction with data from a finite amplitude oscillatory experiment to check the validity of the K-BKZ equation.
The effect of strong pitch angle scattering on the use of artificial auroral streaks for echo detection—Echo 5

Abstract During the Echo 5 experiment launched 13 November 1979 from the Poker Flat Research Range (Fairbanks, Alaska), a 0.75 A, 37 keV electron beam was injected both up and down the field line. The objective of the experiment was to test the use of optical and X-ray methods to detect the beam as it interacted with the atmosphere below the rocket for both the downward injections (markers) and the upward injected electrons which mirrored at the Southern Hemisphere and returned echoes. A ground-based TV system and rocket borne photometers and X-ray detectors viewed the interaction region. The artificial auroral streaks created by the markers were easily visible on the ground TV system but the large intensity of photons produced around the rocket masked any response to the markers by the on-board photometers and X-ray detectors. No echoes were detected with any of the detection systems although the power in some of the upward injections was 7.6 times the power in a detected downward injection thus setting an upper limit on the loss-cone echo flux. The magnitude of the bounce averaged pitch angle diffusion coefficient necessary to explain the lack of observable echoes was found to be 4 × 10−4 s−1. Comparing with calculations done by Lyons (1974) for the pitch angle diffusion of electrons by electrostatic waves, it was found that an equatorial wave electric field of 11 mV m−1 would account for the lack of echoes. Such fields should cause strong pitch angle scattering of up to 10 keV natural electrons and thus be consistent with the presence of diffuse aurora on the Echo 5 trajectory. Direct measurements have also revealed such fields in equatorial regions.
NOx model for lean combustion concept

In an effort to reduce the emissions produced by gas turbine combustors to meet the expected trends of more stringent regulations, a model to calculate NOx produced by lean combustion concepts is proposed. The model simulates the combustor by a number of reactors representing the main combustion as well as pilot zones. A detailed reaction rate scheme was used to provide a fundamental basis for the derivation of reaction temperature and NOx formation expressions. The model validation involved the utilization of the data obtained for a combustor that comprised a prechamber in which fuel was vaporized and mixed with air, and a variable geometry feature to control air split between various zones. In addition to the satisfactory agreement with the measurements obtained under a wide range of operations, the model provided insight into the roles of the primary zone and pilot in forming NOx. The present investigation also shows that multidimensional calculations can provide important assistance for emissions model development. Methods of NOx reduction may be implemented in light of such information.
Mechanisms of object recognition: what we have learned from pigeons.

Behavioral studies of object recognition in pigeons have been conducted for 50 years, yielding a large body of data. Recent work has been directed toward synthesizing this evidence and understanding the visual, associative, and cognitive mechanisms that are involved. The outcome is that pigeons are likely to be the non-primate species for which the computational mechanisms of object recognition are best understood. Here, we review this research and suggest that a core set of mechanisms for object recognition might be present in all vertebrates, including pigeons and people, making pigeons an excellent candidate model to study the neural mechanisms of object recognition. Behavioral and computational evidence suggests that error-driven learning participates in object category learning by pigeons and people, and recent neuroscientific research suggests that the basal ganglia, which are homologous in these species, may implement error-driven learning of stimulus-response associations. Furthermore, learning of abstract category representations can be observed in pigeons and other vertebrates. Finally, there is evidence that feedforward visual processing, a central mechanism in models of object recognition in the primate ventral stream, plays a role in object recognition by pigeons. We also highlight differences between pigeons and people in object recognition abilities, and propose candidate adaptive specializations which may explain them, such as holistic face processing and rule-based category learning in primates. From a modern comparative perspective, such specializations are to be expected regardless of the model species under study. The fact that we have a good idea of which aspects of object recognition differ in people and pigeons should be seen as an advantage over other animal models. From this perspective, we suggest that there is much to learn about human object recognition from studying the “simple” brains of pigeons.
Visibility and seeing

Abstract Visibility is defined as an attribute of the physical characteristics of the object of regard as determined introspectively by an observer possessing normal vision. Therefore seeing may be defined as a function of the visibility of the object and the visual efficiency of the observer. Techniques for the appraisal of visual efficiency have long been available to visual science; and techniques for the appraisal of visibility are needed in illuminating engineering and throughout all practices involving seeing.The significance of visibility, as a factor in seeing, is presented through the medium of correlations with certain psychophysiological effects resulting from seeing under conditions which afford various degrees of visibility. These analyses reveal that visibility and ease of seeing are closely related. The frequency of involuntary blinking has been developed as a criterion of ease of seeing and correlated with measurements of visibility. By these correlations, visibility measurements become of the utmost importance in the science of seeing whose most important objectives involve measurements and interpretations in the realm of supra-threshold seeing.
Transformative learning through open listening: a professional development experience with urban high school teachers

This article relates how an English teacher in an urban high school described his efforts to listen and to perceive a seemingly disaffected student in his efforts to support her learning. He observed her responding to his efforts in positive and unexpected ways that involved her increased involvement in learning in his class. This teacher described how this student had presented many challenges to his teaching and how difficult attending to her overt anger and sullenness in his class was for him. However, by doing so, he said that his perceptions and understandings of her and subsequently, another student, shifted profoundly in ways that he believed helped him help these two students learn more meaningfully in his classes. This example of open listening on the part of a teacher toward his two students opened up new possibilities for learning for all three and may indicate a cycle of transformative listening which will be defined and discussed in this article. Stuart’s experiences in a professional development seminar, facilitated by the author, where teachers’ interpretive and evaluative ideas were listened to openly by colleagues and the facilitator may have influenced Stuart in his responses to his students. His involvement in this study group may have contributed to his learning to see his students in new, unique, and fuller ways, which he said he thought helped him help these students learn better in his classes.
Effects of gamma-sterilization on the physico-chemical properties of natural sediments

Abstract Batch U(VI) sorption/reduction experiments were completed on sterilized and non-sterilized sediment samples to elucidate biological and geochemical reduction mechanisms. Results from X-ray absorption near-edge structure (XANES) spectroscopy revealed that γ-sterilized sediments were actually better sorbents of U(VI), despite the absence of any measurable biological activity. These results indicate that γ-irradiation induced significant physico-chemical changes in the sediment which is contrary to numerous other studies identifying γ-sterilization as an effective and minimally invasive technique. To identify the extent and method of alteration of the soil as a result of γ-sterilization, untreated soil samples, physically separated size fractions, and chemically extracted fractions of the soil were analyzed pre- and post-sterilization. The effects of sterilization on mineralogy, pH, natural organic matter (NOM), cation exchange capacity (CEC), and iron oxidation state were determined. Results indicated that major mineralogy of the clay and whole sediment samples was unchanged. Sediment pH decreased only slightly with γ-irradiation; however, irradiation produced a significant decrease in CEC of the untreated sediments and affected both the organic and inorganic fractions. Mossbauer spectra of non-sterile and γ-sterilized sediments measured more reduced iron present in γ-sterilized sediments compared to non-sterile samples. Our results suggest that sterilization by γ-irradiation induced iron reduction that may have increased the sorption and/or reduction of U(VI) onto these sediments. However, Mossbauer and batch sorption data are somewhat contradictory, the former indicates that the iron oxide or iron hydroxide minerals are more significantly reduced while the later indicates that reduced clay minerals account for greater sorption of U(VI).
A Second Polymorphic Lens Crystallin (LEN-2) in the Mouse: Genetic and Biochemical Analysis of LEN-1 and LEN-2

Two electrophoretic polymorphisms affecting lens crystallins, designated LEN-1 and LEN-2, have been discovered among inbred strains of mice. Analysis by isoelectric focusing demonstrated that both crystallins are monomeric proteins with isoelectric points at or above pH 7. Both proteins eluted in the low molecular weight (LM) fraction upon Sephadex G-200 gel filtration but LEN-2 was shown to be larger than LEN-1 by G75SF gel filtration and denaturing gel electrophoresis. Linkage analysis demonstrated that the genes encoding LEN-1 and LEN-2 assort independently. Amino acid analysis of the allelic products of the two genes revealed that genetic variants of each respective crystallin were very similar in amino acid compositions but that LEN-1 and LEN-2 were dissimilar crystallins.
A planar-reflective symmetry transform for 3D shapes

Symmetry is an important cue for many applications, including object alignment, recognition, and segmentation. In this paper, we describe a planar reflective symmetry transform (PRST) that captures a continuous measure of the reflectional symmetry of a shape with respect to all possible planes. This transform combines and extends previous work that has focused on global symmetries with respect to the center of mass in 3D meshes and local symmetries with respect to points in 2D images. We provide an efficient Monte Carlo sampling algorithm for computing the transform for surfaces and show that it is stable under common transformations. We also provide an iterative refinement algorithm to find local maxima of the transform precisely. We use the transform to define two new geometric properties, center of symmetry and principal symmetry axes, and show that they are useful for aligning objects in a canonical coordinate system. Finally, we demonstrate that the symmetry transform is useful for several applications in computer graphics, including shape matching, segmentation of meshes into parts, and automatic viewpoint selection.
Brain stem serotonin depletion and Ponto-Geniculo-Occipital wave activity in the cat treated with reserpine

Abstract In the first part of this study the time course of depletion of serotonin (5 HT) was determined in several regions of the brain following treatment with reserpine (0.75 mg kg , i.p.). The results were compared with the temporal course of ponto-geniculo-occipital wave activity (PGORes) induced by similar drug treatment. These experiments revealed a good correlation between the initial decrease in 5 HT throughout the brain and the appearance of PGORes. During recovery, however, 5 HT levels remained low at the time when regulation of PGO wave activity began to return to normal. In the second part of this study, the effect upon PGO wave activity of infusions of reserpine into the ventricular and subarachnoid spaces was investigated. Infusions of reserpine phosphate (250 μg) into the fourth ventricle caused changes in wave activity similar to those induced by systemic administration of the drug. In contrast, infusions into several different regions of the subarachnoid space caused only minor changes in PGO wave activity. 5 HT levels, measured at that time when PGORes appeared following infusion of reserpine into the fourth ventricle, were significantly depressed only in the pons. These results are consistent with the hypothesis that monoaminergic neurons exert a tonic inhibitory influence at the brain stem level which serves to regulate or gate REM-type PGO waves.
Dynamical resonances and lifetimes in rigged Hilbert space

Abstract Resonances in rigged Hilbert space are briefly discussed and a resonance width operator is defined by application of a complex scaling transformation to the scattering coordinate. Applications to simple cases of potential scattering are considered.
Nonfatal anaphylaxis caused by oral penicillin: report of case

A case of nonfatal anaphylaxis caused by the ingestion of oral penicillin is reported. The clinical features and a regimen for treatment of anaphylactic shock are described. Severe allergic reactions may occur after the ingestion of oral penicillin. It is essential that the dentist who prescribes the drug is familiar with the rationale for therapy and is equipped to initiate urgently needed treatment.
Optimization of conditions for high temprature capillarary gas chromatography using a split‐mode programmable temprature vaporizing injection system

This paper discribes an investigation into the effects of various operating conditions applied in a PTV-based gas chromatographic system on the performance observed in high temperature analyses. The work comprises a combination of physical and chromatographic measurements, and conclusions are drawn as to the most effective way of using the equipment under evaluation.
Pulmonary vein encircling ablation alters the atrial electrophysiologic response to autonomic stimulation

Pulmonary vein encircling ablation is often effective in the treatment of atrial fibrillation (AF). The success of the procedure does not depend upon creation of continuous lines of block. Thus mechanisms by which pulmonary vein encircling can cure AF remain unclear. Stimulation of cardiac autonomic ganglia alters atrial refractoriness and potentiates AF. We hypothesized that pulmonary vein encircling alters atrial autonomic function and that these alterations account in part for prevention of AF recurrences following ablation. Atrial effective refractory periods (ERP) and AF inducibility were quantified in ten dogs before and during central autonomic nerve stimulation. Pulmonary vein encircling ablation was then performed and electrophysiologic testing repeated. In two dogs subjected to sham procedures measurements were repeated without performance of ablation. Hearts were examined histologically. Autonomic nerve stimulation led to decreased atrial refractoriness and increased AF inducibility and duration. Each of these effects were attenuated following pulmonary vein encircling (e.g., mean ERP decreased before (−23.7 ± 1.8, p < 0.001) but not after ablation (−2.3 ± 1.9, p = 0.25); AF inducibility increased by 26% before vs. 5% after ablation). No attenuation was seen in the sham operated animals. Histologic analysis following pulmonary vein encircling demonstrated destruction of some but not all autonomic ganglia. Autonomic stimulation shortens atrial refractory periods and potentiates AF. Pulmonary vein encircling ablation partially destroys atrial autonomic inputs, attenuates the refractory period shortening effect of autonomic stimulation and decreases AF inducibility. Destruction of autonomic ganglia may contribute to the anti-fibrillatory effects of pulmonary vein encircling and warrants further investigation.
Process capture and modeling via workflow for integrated human-based automated command and control processes

The Virtual Testbed for Advanced Command and Control Concepts (VTAC) program is performing research and development efforts leading to the creation of a testbed for new Command and Control (C2) processes, subprocesses and embedded automated systems and subsystems. This testbed will initially support the capture and modeling of existing C2 processes/subprocesses. Having modeled these at proper levels of abstraction, proposed revisions or replacements to processes, systems and subsystems can be evaluated within a virtual workspace that integrates human operators and automated systems in the context of a larger C2 process. By utilizing such a testbed early in the development cycle, expected improvements resulting from specific revisions or replacements can be quantitatively established. Crossover effects resulting from changes to one or more interrelated processes can also be measured. Quantified measures of improvement can then be provided to decision makers for use in cost-to-performance benefits analysis prior to implementing proposed revisions, replacements, or a sequence of planned enhancements. This paper first presents a high-level view of the VTAC project, followed by a discussion of an example C2 process that was captured, abstracted, and modeled. The abstraction approach, model implementation, and simulations results are covered in detail.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Second-order, exact charge conservation for electromagnetic particle-in-cell simulation in complex geometry

Abstract A second-order, exact charge-conserving algorithm for accumulating charge and current on the spatial grid for electromagnetic particle-in-cell (EM-PIC) simulation in bounded geometry is presented. The algorithm supports standard EM-PIC exterior boundary conditions and complex internal conductors on non-uniform grids. Boundary surfaces are handled by smoothly transitioning from second to first-order weighting within half a cell of the boundary. When a particle is exactly on the boundary surface (either about to be killed, or just created), the weighting is fully first-order. This means that particle creation and particle/surface interaction models developed for first-order weighting do not need to be modified. An additional feature is the use of an energy-conserving interpolation scheme from the electric field on the grid to the particles. Results show that high-density, cold plasmas with ω p e Δ t ∼ 1 , and Δ x / λ D ≫ 1 , can be modeled with reasonable accuracy and good energy conservation. This opens up a significant new capability for explicit simulation of high-density plasmas in high-power devices.
Computer-Assisted Identification of Bacteria on Hot-Boned and Conventionally Processed Beef

Mesophilic and psychotrophic bacteria (706 isolates) obtained from hot-boned and conventionally processed beef at the time of fabrication and after 14-day vacuum storage at 2°C were analyzed by computer-assisted numerical taxonomy (108 attributes per isolate). There was no significant difference in terms of the number of phenons between hot-boned and conventionally processed beef both at the time of fabrication and after storage. Before storage, 24 mesophilic phenons and 11 psychrotrophic phenons were characterized. After storage in vacuum bags, there were 13 mesophilic phenons and 6 psychrotrophic phenons. The after storage flora consisted mainly of Streptococcus and Lactobacillus from both hot-boned and conventionally processed beef.
Effect of Daily Soil Temperature Fluctuations on Soil Electrical Conductivity as Measured with the Geonics® EM-38

Soil electrical conductivity (ECa) measured by electromagnetic induction (EM) using the EM-38 has shown promise as a soil survey tool. Soil temperature influences ECa readings, and temperature can fluctuate considerably in the upper 10cm of the soil during a day. ECa readings were taken in the horizontal and vertical dipole orientations once an hour from 8a.m. to 8p.m. at four sites on three separate days to determine if ECa values were influenced by diurnal temperature variations. Soil temperature readings were taken at the same times at four depths. EM-38 readings remained steady at all four sites all 3days. Linear regression analysis when temperature in the upper 10cm was plotted against ECa yielded low r2 values and slopes, indicating no correlation between soil temperature in the upper 10cm and ECa values. Diurnal changes in soil temperature do not significantly influence soil ECa readings obtained with the EM-38 under the conditions encountered during the study.
Processing techniques for laser speckle derived from biological tissues

Laser speckle techniques are well known in the non-destructive evaluation community. One particular application is to infer strain by monitoring the motion of the speckle pattern that results from coherently illuminating the object. Typically a reference image of the speckle pattern is acquired before deformation of the object. Motion (with respect to this reference image) of subsequent speckle patterns, which occurs when the object is stressed, are used to infer the resulting strain. A problem experienced in using this technique for measurements of hydrated tissues is the rapid decorrelation of the speckle patterns. Thus, application of speckle techniques to assessment of strain in biological tissues relies on rapid sampling of the speckle patterns and the use of processing algorithms that are aimed at inferring strain rates rather than absolute strains. We discuss a number of approaches to estimating strain rates based on sequential speckle patterns. Maximum likelihood methods are shown to be especially useful.
The role of protein solubilization in antigen removal from xenogeneic tissue for heart valve tissue engineering.

Decellularization techniques have been developed in an attempt to reduce the antigenicity of xenogeneic biomaterials, a critical barrier in their use as tissue engineering scaffolds. However, numerous studies have demonstrated inadequate removal and subsequent persistence of antigens in the biomaterial following decellularization, resulting in an immune response upon implantation. Thus, methods to enhance antigen removal (AR) are critical for the use of xenogeneic biomaterials in tissue engineering and regenerative medicine. In the present study, AR methods incorporating protein solubilization principles were investigated for their ability to reduce antigenicity of bovine pericardium (BP) for heart valve tissue engineering. Bovine pericardium following AR (BP-AR) was assessed for residual antigenicity, tensile properties, and extracellular matrix composition. Increasing protein solubility during AR significantly decreased the residual antigenicity of BP-AR-by an additional 80% compared to hypotonic solution or 60% compared to 0.1% (w/v) SDS decellularization methods. Moreover, solubilizing agents have a dominant effect on reducing the level of residual antigenicity of BP-AR beyond that achieved by AR additives alone. Tested AR methods did not compromise the tensile properties of BP-AR compared to native BP. Furthermore, residual cell nuclei did not correlate to residual antigenicity, demonstrating that residual nuclei counts may not be an appropriate indicator of successful AR. In conclusion, AR strategies promoting protein solubilization significantly reduced residual antigens compared to decellularization methods without compromising biomaterial functional properties. This study demonstrates the importance of solubilizing protein antigens for their removal in the generation of xenogeneic scaffolds.
Sequence definition and organization of a human repeated DNA

Abstract DNA sequence data for a DNA repeated sequence, found largely in centromeres of specific human chromosomes is presented. The sequence consists of two tandem 169 and 171 base-pair units that show 27% base variation with each other. In contrast the dimer is more faithfully copied in longer tandem repeats, such as the sequenced 680 base-pair tetramer. In the major sequence of the tetramer, base variation of the order of only 1%, in comparison to the complete dimer is seen. A minimum of two steps in the formation of this sequence is proposed, consisting of evolution of a tandem dimer of two 170 base-pair variant units of a related family within the human genome, and later saltation or amplification of this dimer. No evidence that these sequences contained or evolved from a simpler 6 to 20 base-pair repeat was found, and no homology with known simpler human satellites could be discerned. In reviewing and comparing the literature on repeated DNAs it appears that overall length and tandem repetition are the critical features, rather than individual unit repeat length or secondary structural potential, in defining these sequences as a class and their special centromeric functions and higher chromosome order. The possibility that such sequences arise from a reservoir of interspersed sequences that are common to at least several species is discussed.
Tractorization of agriculture in Pakistan

Perhaps, nothing else symbolizes modernization of agriculture more than the use of tractors in the developing countries. Pakistan is no exception in this regard, where tractors, its accompanying machines, tube-wells, and biological technology is seen as the only mechanism to salvage the precarious economy. In recent years, the pace of mechanization has increased, in spite of the fact that practioners and planners have widely divergent views on the merits of tractorization. This paper attempts to present the characteristics of Pakistan's agriculture from an adaptive view-point, suggesting critical elements that sustain its long-term viability. The role of cultural and genetic information is analyzed to explain the man-environment relationship. In the final section, role of tractors and their impact on agriculture is discussed. Tube-wells, other machines, fertilizers, and biological technology are not discussed in this paper.
Receptive field properties of neurons in the visual cortex of the rat.

Abstract The receptive field properties of neurons were examined in the visual cortex, area 17, of Long-Evans pigmented rats. Visually responsive cells comprised 90% of cells recorded in area 17. Five percent of these cells responded only to stationary stimuli, while the remaining responded to both stationary and moving stimuli or only to movement. Cells of the latter category were classified as complex (44%), simple (27%), hypercomplex (13%) or non-oriented (16%). The results presented here show that, contrary to existing reports, neurons in the rat visual cortex have well-defined receptive field properties.
Membrane-associated and Solubilized ATPases of Streptococcus mutans and Streptococcus sanguis

The proton-translocating, membrane ATPases of oral streptococci have been implicated in cytoplasmic pH regulation, acidurance, and cariogenicity. Membranes were isolated from Streptococcus mutans GS-5 and Streptococcus sanguis NCTC 10904 following salt-induced lysis of cells treated with lysozyme and mutanolysin. The ATPase activities of these membranes were 1.8 and 1.1 units per mg membrane protein, respectively. F1 ATPases were washed free from the membranes and purified by fast protein liquid chromatography (FPLC). Hydrolytic activities of the F1 ATPases were maximal at pH values between 6.0 and 6.6, whereas the membrane-bound enzymes had pH maxima of 7.5 (S. sanguis) and 6.0 (S. mutans). The F1 ATPases of the streptococci were similar to the well-characterized enzyme of Escherichia coli; they consisted of five different polypeptides and had apparent, aggregate molecular weights of from 335 to 350 Kd. The membrane-bound ATPases were characterized biochemically and found to be similar to those of proton-translocating ATPases of E. coli and Streptococcus faecalis. Km values for the membranes with respect to ATP were found to be 0.9 and 1.0 mmol/L for S. mutans and S. sanguis, respectively. Both enzymes had specificities for purine triphosphates and were active with a variety of divalent cations, although optimal activity occurred with ATP and Mg. The membrane-associated enzymes were sensitive to the inhibitors dicyclohexylcarbodiimide (DCCD) and azide, but insensitive to ouabain and vanadate.(ABSTRACT TRUNCATED AT 250 WORDS)
Hypoxia induces cardiac malformations via A1 adenosine receptor activation in chicken embryos.

BACKGROUND: The current understanding of the effects of hypoxia on early embryogenesis is limited. Potential mediators of hypoxic effects include adenosine, which increases dramatically during hypoxic conditions and activates A1 adenosine receptors (A1ARs). METHODS: To examine the influences of hypoxia and adenosine signaling on cardiac development, chicken embryos were studied. Real time RT-PCR assay was used to examine the A1AR gene expression during embryogenesis and after siRNA- mediated knock down. Cell proliferation was determined by counting cell nuclei and PhosphoHistone H3 positive cells. Apoptosis was determined by TUNEL assay. RESULTS: A1ARs were found to be expressed in chicken embryos during early embryogenesis. Treatment of Hamburger and Hamilton stage 4 embryos with the A1AR agonist N 6 -cyclopentyladenosine caused cardiac bifida and looping defects in 55% of embryos. Hamburger and Hamilton stage 4 embryos exposed to 10% oxygen for 6, 12, 18, and 24 h followed by recovery in room air until stage 11, exhibited cardia bifida and looping defects in 34, 45, 60, and 86% of embryos respectively. Hypoxia-induced abnormalities were reduced when A1AR signaling was inhibited by the A1AR antagonist 1,3 dipropyl-8-cyclopentylxanthine or by siRNA-targeting A1ARs. Hypoxia treatment did not increase apoptosis, but decreased embryonic cell proliferation. CONCLUSIONS: These data indicate that hypoxia adversely influences cardiac malformations during development, in part by A1AR signaling. Birth Defects Research (Part A) 82:121–130, 2008. 2008 Wiley-Liss, Inc.
On the stability of an adjustment process for spatial price equilibrium modeled as a projected dynamical system

Abstract This paper presents a stability study for the continuous-time adjustment process proposed for the perfectly competitive spatial price equilibrium problem modeled as a projected dynamical system by Nagurney, Takayama, and Zhang (1995). Two distinct approaches are adopted here for establishing the stability of the spatial price equilibrium under such an adjustment process. One approach utilizes the monotonicity condition on the supply prices, demand prices, and transaction costs to develop various stability properties. The other utilizes the regularity concept, adapted from Zhang and Nagurney (1995), which enables us to explore the stability of the adjustment process — a nonstandard dynamical system, via its minimal face flow — a standard dynamical system.