cssi/SciSciGPT-SciSciNet huggingface dataset:
Variability and stability of a dragonfly assemblage

Using 12 years of monthly sweep-net data from 9–12 permanent sampling stations, we evaluated the variability and stability of the dragonfly assemblage in Bays Mountain Lake (northeastern Tennessee, USA). To do this, we adopted the view that a stable assemblage (i.e. one capable of recovering quickly from disturbances) should have low variability (i.e. high persistence of taxa, relatively constant densities, and high rank concordance), except with disturbances more intense and frequent than those in this system. Moreover, a stable assemblage should contain populations that exhibit density dependence and should tend to remain within a restricted range of densities (boundedness), shifting toward a narrow density interval between generations (attraction). To test some specific predictions derived from these views, we analyzed 12-year sequences of larval population sizes just before the onset of emergence for the 13 dominant dragonfly taxa in the lake. Most but not all of the 13 dominant taxa persisted during the 12-year period. Variabilities of taxon densities, measured as standard deviations across generations of log-transformed population sizes, were representative of the broad range for other invertebrates but somewhat higher than those of terrestrial vertebrates. There were fewer than three significant abundance trends over the 12-year period, and rank concordance between generations was high (W=0.716). Density dependence was detected among some of the dragonfly density sequences by five different methods. Using techniques presented in the companion paper, we found strong indications of both boundedness and attraction in the whole assemblage. We conclude tentatively that an assemblage consisting of at least 11 of the 13 dominant dragonfly taxa at Bays Mountain Lake has low-to-moderate variability and is stable, but that the complete 29-species assemblage is probably not stable at the scale of this single lake. We emphasize the need for coupling such long-term descriptive analyses with studies of responses to experimental disturbances.
Intramolecular amide stacking and its competition with hydrogen bonding in a small foldamer.

Attractive interactions between two carboxamide groups in a “stacked” geometry are explored under isolated molecule conditions. Infrared spectra of single conformations of a small γ-peptide, Ac-γ2-hPhe-NHMe, reveal the presence of a conformation in which the two amide planes are approximately parallel with the amide dipoles in an antialigned orientation. This stacked conformation is energetically comparable to conformations that contain an intramolecular amide−amide H-bond. Amide stacking interactions can compete with H-bonding in circumstances where the amide groups can be brought into a stacking configuration with minimal strain, opening the way for its use in the design of future foldamer structures.
Diffraction analysis of photoanisotropic holography: an anisotropic saturation model

The photoisomerization of a highly anisotropic dye molecule depends not only on the intensity but also on the polarization state of the acting light with respect to the molecular axis. Polarization-dependent isomerization of uniformly oriented distributions of anisotropic dye molecules produces an orientational distribution of photoexcited states. Saturation occurs when all the molecules aligned in a particular orientation are isomerized so further photoexcitation cannot occur. This anisotropic saturation occurs first in the direction aligned with the incident polarization. We investigate this anisotropic saturation behavior and present a theoretical model that incorporates intensity saturation for describing holographic diffraction in dynamic photoanisotropic organic materials. Numerical simulations of diffraction versus intensity and polarization are provided and compared with the experimental results.
Acute effect of psychologic stimuli upon plasma non-esterified fatty acid level.

Summary1. Serum non-esterified fatty acids (NEFA) and triglyceride (TG) levels were measured in four normal individuals during difficult levels of emotional arousal. 2. Periods of arousal in which feelings of anxiety and/or hostility were evoked were accompanied by rises in serum NEFA levels, but not of TG levels.
Volume rendering segmented data using 3D textures: a practical approach for intra-operative visualization

Volume rendering has high utility in visualization of segmented datasets. However, volume rendering of the segmented labels along with the original data causes undesirable intermixing/bleeding artifacts arising from interpolation at the sharp boundaries. This issue is further amplified in 3D textures based volume rendering due to the inaccessibility of the interpolation stage. We present an approach which helps minimize intermixing artifacts while maintaining the high performance of 3D texture based volume rendering - both of which are critical for intra-operative visualization. Our approach uses a 2D transfer function based classification scheme where label distinction is achieved through an encoding that generates unique gradient values for labels. This helps ensure that labelled voxels always map to distinct regions in the 2D transfer function, irrespective of interpolation. In contrast to previously reported algorithms, our algorithm does not require multiple passes for rendering and supports greater than 4 masks. It also allows for real-time modification of the colors/opacities of the segmented structures along with the original data. Additionally, these capabilities are available with minimal texture memory requirements amongst comparable algorithms. Results are presented on clinical and phantom data.
Elevated basal firing rates and enhanced responses to 8-Br-cAMP in locus coeruleus neurons in brain slices from opiate-dependent rats

Extracellular, single unit activity was recorded in noradrenergic neurons of the nucleus locus coeruleus (LC) in brain slices prepared from rats treated chronically with morphine. In contrast to previous reports, basal firing rates of LC neurons were 2-fold higher in slices from opiate-dependent animals compared to controls and they remained elevated for at least 7 h. In neurons from dependent animals the maximal excitation in response to 8-bromoadenosine 3′:5′-cyclic monophosphate (8-Br-cAMP), but not the EC50, was found to be substantially greater than in controls. This result parallels biochemical evidence of an up-regulation of the cAMP pathway in the LC of opiate-dependent animals. There was no difference in the response to glutamate between cells from dependent and control animals. We conclude that an increase in basal firing rate, possibly mediated by an up-regulation of the intrinsic cAMP pathway, contributes to the hyperactivity of the LC during opiate withdrawal in vivo.
Energy conservation techniques as innovations, and their diffusion

Abstract Many effective products, procedures, and techniques for achieving energy conservation have been discovered by researchers. This paper focuses on the conditions under which these procedures and techniques will be adopted voluntarily. It is suggested, first, that an economic incentive for the utilization of those energy-conserving techniques is not a sufficient condition for their adoption, and second, that a psychologically-based theory of the diffusion of innovation will identify the critical variables for promoting the adaption of energy-conserving products and techniques. Based on preliminary, small-scale observations of homeowners' reactions to a complex, time-controlled thermostat, the initial parameters of a diffusion theory for energy innovation are suggested.
Finite element convergence for singular data

Convergence of the finite element solutionu h of the Dirichlet problem Δu=? is proved, where ? is the Dirac ?-function (unit impulse). In two dimensions, the Green's function (fundamental solution)u lies outsideH 1, but we are able to prove that $$\parallel u - u^h \parallel _{L^2 } = O (h)$$ . Since the singularity ofu is logarithmic, we conclude that in two dimensions the function log ? can be approximated inL 2 near the origin by piecewise linear functions with an errorO (h). We also consider the Dirichlet problem Δu=f, wheref is piecewise smooth but discontinuous along some curve. In this case,u just fails to be inH 5/2, but as with the approximation to the Green's function, we prove the full rate of convergence:?u?u h ?1=O (h 8/2) with, say, piecewise quadratics.
Promoting Gender Equity in Middle Level and Secondary School Sports Programs.

Sports equity is important at the middle and secondary school levels, not only to increase opportunities for women in sports and physical activity, but to change perceptions—particularly the incorrect percep tion that sports participation is not important for girls and women.
Energy Doubler/Saver Safety Leads

A special type of cryogenic current lead is described and its thermal evaluation is presented. This high voltage insulated lead was designed for heavy electrical conduction only during the quench of a superconducting magnet and for minimal heat leak.
Analytic design methods for wave rotor cycles

A procedure to design a preliminary wave rotor cycle for any application is presented. To complete a cycle with heat addition there are two separate—but related—design steps that must be performed. Selection of a wave configuration determines the allowable amount of heat added in any case, and the ensuing wave pattern requires associated pressure discharge conditions to allow the process to be made cyclic. This procedure, when applied, gives a first estimate of the cycle performance and the necessary information for proceeding to the next step in the design process, namely, the application of a characteristic-based or other appropriate detailed onedimensional wave calculation that locates more precisely the proper porting around the periphery of the wave rotor. Examples of the design procedure are given to demonstrate its utility and generality. These examples also illustrate the large gains in performance that might be realized with the use of wave rotor enhanced propulsion cycles.
Effects of Grain Alignment on Fabric Mechanical Properties

This study was designed to measure the effect of grain alignment on selected fabric physical and mechanical properties. Kawabata's Shear Tester and Pure Bending Tester were used to assess shear and bending properties of 19 apparel fabrics. Fabric samples were cut at six different grain alignment variations. Shear properties were more sensitive than bending properties to variations in grain alignment. Significant positive correlations were identified between tilt and shear stiffness and hysteresis measurements. Although bending modulus and hysteresis values were not significantly related to tilt, a trend toward decreased bending values with increased tilt angles was observed. Results confirm a previous study by Orzada, Moore, and Collier (1997).
Assignment of the genes for human lambda immunoglobulin chains to chromosome 22.

Human immunoglobulin chains are expressed in somatic cell hybrids between mouse myeloma cells and human B cells1,2. By correlating the expression of human immunoglobulin chains and the presence of specific human chromosomes in the hybrid clones, we have assigned the human immunoglobulin heavy-chain gene cluster to human chromosome 14 (refs 1,2). We have now studied somatic cell hybrids between mouse myeloma cells and either human peripheral lymphocytes or different human λ chain-secreting lymphoblastoid cell lines. Somatic cell hybrid clones were pre-selected for their ability to produce human λ immunoglobulin chains, and studied for the expression of isozyme markers assigned to each of the different human chromosomes. Subclones of human λ chain-secreting hybrid clones were also studied. The results indicate that human chromosome 22 carries the human λ immunoglobulin chain genes.
A GnRH/LH Surge Without Subsequent Progesterone Exposure Can Induce Development of Follicular Cysts

Our hypothesis was that follicular cysts would develop if cows experienced an estradiol-induced GnRH LH surge in the absence of an ovulatory follicle. Further, we hypothesized that estradiol would fail to induce a subsequent GnRH/LH surge in these cows until they were treated with progesterone. In experiment 1, seven cows were synchronized with a controlled internal drug releasing device (CIDR) for 9 d and each received 500 microg of cloprostenol on d 7. All follicles (> or = 5 mm in diameter) were aspirated at the time of CIDR removal using transvaginal follicular aspiration. Two days after aspiration, cows were treated with 5 mg of estradiol benzoate (EB) to induce a GnRH/LH surge in the absence of an ovulatory-sized follicle. All cows had an LH surge following the estradiol treatment and three of seven developed an anovulatory condition that resembled follicular cysts. The four cows that did not develop follicular cysts luteinized remaining cells from one aspirated follicle each. Thus, all cows with a progesterone elevation after the estradiol/GnRH/LH surge had subsequent ovulatory cycles, whereas the absence of progesterone was followed by follicular cysts. After 49 d, the anovulatory cows were induced back to normal cyclicity by insertion of a CIDR for 7 d. In two subsequent experiments, nine of 26 cows were induced to have follicular cysts by follicular aspiration followed by 5 mg of EB. After 26 d of observation, all cystic cows received a second treatment with 5 mg of EB and none of the cows showed an LH surge or ovulation. Cystic cows were untreated (n = 4 controls) or treated for 7 d with a CIDR (n = 5). All cystic cows were subsequently treated for a third time with 5 mg of EB. All CIDR-treated cows had an LH surge and ovulated, whereas none of the control cows had an LH surge or ovulation after the estradiol treatment. Thus, a large follicle anovulatory condition, similar to follicular cysts, can be induced by estradiol induction of a GnRH/LH surge in the absence of subsequent luteinization, and this condition prevents a GnRH/LH surge in response to high doses of estradiol. Progesterone eliminates this condition by reinitiation of GnRH/LH surges in response to estradiol.
Volterra-Verhulst prey-predator systems with time dependent coefficients: Diffusion type approximation and periodic solutions

In treating the Volterra-Verhulst prey-predator system with time dependent coefficients, we ask how far this deterministic system represents or approximates the dynamics of the population evolving in a realistic environment which is stochastic in nature. We consider a stochastic system with small Gaussian noise type fluctuations. It is shown that the higher moments of the deviation of the deterministic system from the stochastic approach zero as the strength δ of the perturbation decays to zero. For any δ >0 and all T >0, ɛ >0, the sample population paths that stay within ɛ distance from the deterministic path during [0, T ] form a collection of positive probability. In comparing the stationary distributions of the two systems, we show that the weak limits of those of the stochastic system form a subset of those of the deterministic system. This is in analogy with a result of May connected with the stability of the two systems. Plant and rodent populations possess periodic parameters and exhibit periodic behavior . We establish theoretically this periodicity under periodicity conditions on the coefficients and perturbing random forces. We also establish a central limit property for the prey-predator system.
A synthetic fibrin cross-linking polymer for modulating clot properties and inducing hemostasis

Clotting factor replacement is the standard management of acute bleeding in congenital and acquired bleeding disorders. We present a synthetic approach to hemostasis using an engineered hemostatic polymer (PolySTAT) that circulates innocuously in the blood, identifies sites of vascular injury, and promotes clot formation to stop bleeding. PolySTAT induces hemostasis by cross-linking the fibrin matrix within clots, mimicking the function of the transglutaminase factor XIII. Furthermore, synthetic PolySTAT binds specifically to fibrin monomers and is uniformly integrated into fibrin fibers during fibrin polymerization, resulting in a fortified, hybrid polymer network with enhanced resistance to enzymatic degradation. In vivo hemostatic activity was confirmed in a rat model of trauma and fluid resuscitation in which intravenous administration of PolySTAT improved survival by reducing blood loss and resuscitation fluid requirements. PolySTAT-induced fibrin cross-linking is a novel approach to hemostasis using synthetic polymers for noninvasive modulation of clot architecture with potentially wide-ranging therapeutic applications.
Comparison of heterojunction bipolar transistors in stripe and dot geometries

Abstract The emitter crowding effects and the base resistances are determined for two HBT layout designs: the conventional stripe geometry and the dot geometry. Critical design parameters such as the emitter width and base contact width for the stripe geometry HBTs, and the emitter radius for the dot geometry HBTs are calculated for optimized device performance. The advantages and disadvantages of choosing either device geometry are discussed. In addition, measured high frequency performance of HBTs in both device geometries are compared.
Managed Competition Meets Tax-Neutrality

be possible to design a budget-neutral universal system of refundable tax credits, budget-neutrality is more problematic in a dual system of exemptions and credits. The reason for this relates to the difficulty of indexing the tax credit to reflect changes in the value of insurance. Let us assume that the tax credit is calibrated to the average value of a conventional insurance plan, as Pauly and Goodman suggest it should be. If consumers who are characteristically low risk elect the MSA/ catastrophic plan combination over conventional insurance, adverse selection will drive up the price of conventional insurance. Unless some method is devised to recalibrate the tax credit, the value of these credits also will rise. Similar to Medicare’s problems with calculating appropriate capitation payments for Medicare risk contracts, consumer choices that maximize individual economic advantage in a dual system are likely also to maximize public expenditures. While one might imagine that we could devise some fair method of indexing the tax credit that would make a dual system budgetneutral, it is hard to imagine that this would be simple to explain to voters who jealously guard their tax advantages. Drawing down our political capital. In summary, it is difficult to see that the Pauly/ Goodman proposal offers enough to warrant taking it to the public. Our health care system is plagued by serious problems that we sought to address in a national debate last year. In the wake of that failure, none of these problems has eased. The number of uninsured Americans continues to increase, even as Medicaid enrollment expands. The cost of health care continues to rise and to swallow an ever-larger share of our gross national product. Medicare is edging further toward insolvency. And the American public is becoming increasingly intolerant of the failure of our paid representatives to put our national house in order. If we are to draw down our remaining political capital to change the health care system, we need a proposal that addresses the system’s most egregious problems directly and effectively. This proposal does not.
Immunologic Study of Tumors in Mouse Models

Mouse tumor models have played a central role in the history of cancer immunology and more broadly in immunology. Studies of transplantable tumors opened the field of transplantation immunology. Serologic analyses of antibodies against tumors led to the discovery of major histocompatibility complex (MHC) antigens that determine transplantation immunity as well as other alloantigens and lymphocyte subset markers, including the well-known CD4+ and CD8+ subsets of T cells. In the present era, genetically manipulated mice are crucial tools to (1) understand the role of various components and cells of the immune system in promoting, accelerating, or rejecting tumors; (2) investigate immunity against cancers at different stages of tumor progression; and (3) develop and test new prevention and therapeutic strategies against cancer. Keywords: tumors; mouse models; immunologic study; transplantable tumor models; tumor antigens; immune surveillance; tumor rejection; study mechanisms; cancer immunotherapy
Spectral Characteristics of a 140-GHz Long-Pulsed Gyrotron

Gyrotrons operating in the millimeter and submillimeter wavelength ranges are the promising sources for applications that are requiring good spectral characteristics and a wide range of output power. We report the precise measurement results of gyrotron spectra. Experiments were conducted using a 140-GHz long-pulse gyrotron that is developed for the dynamic nuclear polarization/nuclear-magnetic-resonance spectroscopy at the Massachusetts Institute of Technology. Transient downshift of the frequency by 12 MHz with a time constant of 3 s was observed. After reaching equilibrium, the frequency was maintained within 1 ppm for over 20 s. The coefficient of the frequency change with cavity temperature was -2.0 MHz/K, which shows that fine tuning of the gyrotron frequency is plausible by cavity-temperature control. Frequency pulling by the beam current was observed, but it was shown to be masked by the downward shift of the gyrotron frequency with temperature. The linewidth was measured to be much less than 1 MHz at 60 dB relative to the carrier power [in decibels relative to carrier (dBc)] and 4.3 MHz at 75 dBc, which is the largest dynamic range to date for the measurement of gyrotron linewidth to our knowledge.
Rate Making for Farm-Level Crop Insurance: Implications for Adverse Selection

This research identifies two problems in the new Federal Crop Insurance that may cause adverse selection: (a) the relationship between rate making and expected yields for individual farmers, and (b) the bias introduced in coverage protection when trends are not used to establish expected yields. A theoretical investigation using the normality assumption demonstrates the potential severity of these problems, and empirical results from farm-level data lend further support. As crop insurance changes to individualized methods of protection, these issues will be particularly important for developing rates.
The effect of sensor/actuator asymmetries in haptic interfaces

Haptic interfaces enable us to interact with virtual objects by sensing our actions and communicating them to a virtual environment. A haptic interface with force feedback capability will provide sensory information back to the user thus communicating the consequences of his/her actions. The quality and complexity of these interactions is dependent on how the interface is designed. When designing a haptic interface, one must choose how many sensors and how many actuators will be used. In particular we are now seeing interfaces which have more sensors than actuators. This "asymmetry" in sensor/actuator utilization provides for a higher dimensionality of action than sensory feedback. It is a tempting avenue for devices design due to the low cost of introducing more sensors. Yet, while this can enable more rich exploratory interactions, the lack for equal dimensionality in force feedback can lead to interactions which are energetically non-conservative. in this paper we provide a preliminary view of the properties of such "asymmetric" sensor/actuator designs. We address the design and rendering tradeoffs of these systems and introduce a framework for device analysis.
Options in the solar system for planetary surface exploration via hopping

This paper provides an initial overview of the capabilities of hopping vehicles, and examines planetary bodies in the solar system which might be amenable to exploration via hopping. A hopping vehicle is one which uses ballistic propulsive action, rather than ground contact or action on a surrounding fluid, to propel itself1 2. The paper examines how gravity levels, atmospheric densities, and surface characteristics affect the attractiveness of a planetary body to hopping missions. An initial catalogue of planetary bodies where hopping missions could take place is provided.
Hepatic inflammation in rats with experimental small intestinal bacterial overgrowth

Abstract Hepatobiliary inflammation and other extraintestinal manifestations accompany certain intestinal disorders, perhaps because of proliferation or enhanced transport of luminal bacteria or their phlogistic cell-wall components. Using jejunal self-filling blind loops to create small bowel bacterial overgrowth, we compared biochemical and histological evidence of hepatic inflammation in 3 rat strains chosen for their variable inflammatory responses to bacterial cell wall polymers. Lewis and Wistar rats developed weight loss, hepatomegaly, and hepatic inflammation 4 and 12 wk, respectively, after creation of SFBL. Plasma aspartate aminotransferase levels in Lewis rats 4 wk (578 ± 77 U/L) and Wistar rats 12 wk (220 ± 35 U/L) after self-filling blind loops were significantly greater than in rats with self-emptying blind loops (112 ± 24 U/L, p
Thiaindanones: Thiophene Isosteres of Indanone

The preparation of substituted 4- and 6-thiaindanones 1 (thiophene isosteres of indanone) via intramolecular acylation of β-(2- and 3-thienyl)propanoic acids is described. The Wolff-Kishner and sodium borohydride reductions provided the corresponding thiaindan and thiaindanol (thiophene isosteres of indan and in-danol), respectively.
Characteristics of integrated MOM junctions at DC and at optical frequencies

We present a new metal-oxide-metal device (Ni-NiO-Ni, "Edge MOM") which is stable, reproducibly fabricated, and with a 10-10-cm2tunneling area. Performing detection experiments, the device's nonlinear I-V characteristic is shown to be invariant at audio frequencies, 10.6, 3.39, and 0.6328 μm. Similar devices with 10-8-cm2tunneling areas perform as well as the Edge MOM's in the visible and the near-infrared range, but deteriorate in performance at the 10-μm range. A dominant competing effect is a thermal-induced signal, which increases with frequency and temperature. Coupling mechanisms at the various regimes are investigated. The device can serve as a broad-band detector and mixer, and might in the future be a basic element of broad-band amplifiers and oscillators.
HIV seroconverting donors delay their return: screening test implications.

BACKGROUND: The yield of HIV p24 antigen testing implemented in March 1996 has been lower than projected. One possible explanation is that HIV seroconverting donors delay their return because of the recent practice of risk behaviors and/or signs and symptoms associated with primary infection. STUDY DESIGN AND METHODS: From a database of 6.8-million allogeneic donations collected at five U.S. blood centers from 1991 to 1997, 49 HIV, 21 HCV, 32 HTLV, and 44 HBsAg seroconverters with at least three donations were identified. A statistical method was developed to investigate whether the time between a donor's last negative donation and their positive donation was significantly longer than expected based on their previous return history. RESULTS: HIV seroconverters returned on average 42 percent later than expected (p < 0.01). Although not significant, HCV seroconverters donated on average 43 percent earlier than expected. HTLV and HBsAg seroconverters did not appear to change their donation pattern around the time of seroconversion. Sixty-three percent of the HIV seroconverters later acknowledged practicing a high-risk behavior. CONCLUSIONS: HIV seroconverters delay their return around the time of seroconversion and are thus less likely to be recently infected. Unique among HIV seroconverters, this observation provides a possible explanation for the lower than expected yield of HIV p24 antigen testing and suggests that NAT may have a similar low yield.
Pathfinder : A parallel search algorithm for concerted atomistic events

An algorithm has been designed to search for the escape paths with the lowest activation barriers when starting from a local minimum-energy configuration of a many-atom system. The pathfinder algorithm combines: (1) a steered eigenvector-following method that guides a constrained escape from the convex region and subsequently climbs to a transition state tangentially to the eigenvector corresponding to the lowest negative Hessian eigenvalue; (2) discrete abstraction of the atomic configuration to systematically enumerate concerted events as linear combinations of atomistic events; (3) evolutionary control of the population dynamics of low activation-barrier events; and (4) hybrid task + spatial decompositions to implement massive search for complex events on parallel computers. The program exhibits good scalability on parallel computers and has been used to study concerted bond-breaking events in the fracture of alumina.
Sexual conflict as a partitioning of selection.

Sexual conflict appears to be a powerful force in evolution. We suggest that selection theory can readily be adapted for cases of sexual conflict and illustrate how it can provide a new perspective on what traits cause conflict and might respond to its presence. Use of selection theory resolves some terminological confusion, provides operational measures of conflict and generates a conceptual tool for parsing the causes and consequences of conflict in complex systems of male–female interactions.
Band of cacophony - abdominal catastrophe caused by the fibrous band of Meckel's diverticulum: a case report.

Introduction: This report calls attention to small bowel necrosis resulting as a complication of formation of an obstructive loop of small bowel around a band of Meckel’s diverticulum. Case presentation: We report a case of an adult in his 5th decade presenting with sharp, colicky abdominal pain. On presentation his vitals were within normal limits, abdomen was non-distended but tender and rigid all over, more on left lower quadrant without any rebound tenderness. Bowel sounds were hypoactive. Rectal exam showed an empty vault. White blood cell count was 9.0 x 10 3 /mm 3 with 94.5% neutrophils, Hb of 9.0 gm/dl and Hct of 31.3%, liver and pancreatic enzymes were not elevated. Arterial blood gas did not show any acidosis and lactic acid level was not elevated. X-ray showed a non-obstructive bowel pattern without any free air. Abdominal computed tomography with oral and intravenous gastrograffin showed findings consistent with complete mid to distal small bowel obstruction secondary to a closed loop obstruction. Emergent laparotomy showed a Meckel's diverticulum that had formed a band around a portion of small bowel causing it to twist upon itself and become necrotic. Conclusion: Histopathology revealed Meckel’s diverticulum and benign intestinal tissue with hemorrhagic necrosis.
Aortic intramural hematoma presenting as angina

We present a case of intramural hematoma initially misdiagnosed as angina, and requiring myocardial revascularization. Angiography failed to lead to the proper diagnosis and the original transesophageal echocardiogram was misinterpreted as showing an intimal flap that was actually an echocardiographic artifact. The echocardiographic characteristics and implications of this entity are reviewed.
Modeling parallel and reactive empathy in virtual agents: an inductive approach

Humans continuously assess one another's situational context, modify their own affective state, and then respond based on these outcomes through empathetic expression. Virtual agents should be capable of similarly empathizing with users in interactive environments. A key challenge posed by empathetic reasoning in virtual agents is determining whether to respond with parallel or reactive empathy. Parallel empathy refers to mere replication of another's affective state, whereas reactive empathy exhibits greater cognitive awareness and may lead to incongruent emotional responses (i.e., emotions different from the recipient's and perhaps intended to alter negative affect). Because empathy is not yet sufficiently well understood, it is unclear as to which type of empathy is most effective and under what circumstances they should be applied. Devising empirically informed models of empathy from observations of "empathy in action" may lead to virtual agents that can accurately respond in social situations.This paper proposes a unified inductive framework for modeling parallel and reactive empathy. First, in training sessions, a trainer guides a virtual agent through a series of problem-solving tasks in a learning environment and encounters empathetic characters. The proposed inductive architecture tracks situational data including actions, visited locations, intentions, and the trainer's physiological responses to generate models of empathy. Empathy models are used to drive runtime situation-appropriate empathetic behaviors by selecting suitable parallel or reactive empathetic expressions. An empirical evaluation of the approach in an interactive learning environment suggests that the induced empathy models can accurately assess social contexts and generate appropriate empathetic responses for virtual agent control.
Analysis of current crowding effects in multiturn spiral inductors

The effective trace resistance of a multiturn spiral inductor operating at high frequencies is known to increase dramatically above its dc value, due to proximity effect or current crowding. This phenomenon, which dominates resistance increases due to skin effect, is difficult to analyze precisely and has generally required electromagnetic simulation for quantitative assessment. Current crowding is studied in this paper through approximate analytical modeling, and first-order expressions are derived for predicting resistance as a function of frequency. The results are validated through comparisons with electromagnetic simulations and compared with measured data taken from a spiral inductor implemented in a silicon-on-sapphire process.
Guyanese Amerindian epistemology: the gift from a pacifist insurgence

This article introduces the idea that Amerindian modes of knowledge are intellectual strategies for defeating racism in Guyana. It is suggested that coming to terms with radically different concepts of time and space provides the means for understanding viable alternatives of social being. The current invisibility of, or deleterious prejudice against, indigenous Amerindian renderings of social being serve merely as opportunities lost to a postcolonial state, which might otherwise apply new forms of power and polity and offer these to both the nation and the global community. The familiar use of essentialism or, even, of multivocality, which some indigenous peoples have to implement to combat racism, is not good politics, it is argued. Indeed, providing the means for identifying and sympathetically understanding the different modes of knowing the world is good political action.
Pregnenolone in man: plasma levels in states of normal and abnormal steroidogenesis.

ABSTRACT Using a recently described radioimmunoassay, plasma pregnenolone was measured in subjects with normal and abnormal steroidogenesis. Plasma levels were found to be higher in premenopausal women than men and higher in men than in postmenopausal women. Adrenal suppression decreased plasma pregnenolone in normal subjects and gonadal suppression decreased plasma pregnenolone in premenopausal women and men but not in postmenopausal women. Adrenal plus gonadal suppression reduced plasma pregnenolone levels below the sensitivity of the assay i.e., <0.1 ng/ml. Plasma pregnenolone was similar during the follicular and luteal phases of 4 menstrual cycles. Plasma pregnenolone rose in response to the administration of large doses of ACTH to 5 normal subjects. A diurnal rhythm of plasma pregnenolone was observed only in postmenopausal women and in premenopausal women taking estrogen. This suggests that pregnenolone of ovarian origin may have obscured a diurnal rhythm of adrenal pregnenolone in premenopausal wo...
Uncovering a Role for the Tail of the Dictyostelium discoideum SadA Protein in Cell-Substrate Adhesion

Previous work from our laboratory showed that the Dictyostelium discoideum SadA protein plays a central role in cell-substrate adhesion. SadA null cells exhibit a loss of adhesion, a disrupted actin cytoskeleton, and a cytokinesis defect. How SadA mediates these phenotypes is unknown. This work addresses the mechanism of SadA function, demonstrating an important role for the C-terminal cytoplasmic tail in SadA function. We found that a SadA tailless mutant was unable to rescue the sadA adhesion deficiency, and overexpression of the SadA tail domain reduced adhesion in wild-type cells. We also show that SadA is closely associated with the actin cytoskeleton. Mutagenesis studies suggested that four serine residues in the tail, S924/S925 and S940/S941, may regulate association of SadA with the actin cytoskeleton. Glutathione S-transferase pull-down assays identified at least one likely interaction partner of the SadA tail, cortexillin I, a known actin bundling protein. Thus, our data demonstrate an important role for the carboxy-terminal cytoplasmic tail in SadA function and strongly suggest that a phosphorylation event in this tail regulates an interaction with cortexillin I. Based on our data, we propose a model for the function of SadA.
A comparative study of load sharing in heterogeneous multicomputer systems

The effective use of a heterogeneous multicomputer system depends on the scheduling policy used. Often the scheduling algorithms used are those that were intended for homogeneous systems. On the other hand, most scheduling algorithms designed with heterogeneity in mind were developed under unrealistic assumptions. To enhance the performance of a multicomputer system, load sharing can be used during scheduling to distribute the workload evenly among the constituent nodes. This paper presents a comprehensive evaluation of load sharing algorithms in heterogeneous multicomputer systems. The simulation results suggest that load sharing policies that perform well in homogeneous systems fail to achieve good performance in heterogeneous systems. The authors also show that the distribution of service time and the communication overhead have significant impact on system performance. They conclude by providing guidelines for selecting load sharing policies suitable for different heterogeneous environments. >
The congressional office of technology assessment a retrospective and prospects for the post-OTA world

The Office of Technology Assessment (OTA) was established to serve the United States Congress. In return, however, Congress contributed uniquely to the technology assessment process as it was implemented by OTA It will be enormously challenging to establish the conditions provided by congressional stewardship that enabled OTA's uneasy but effective marriage of expert advice and democratic participation. These congressional contributions are analyzed and implications for future new technology assessment institutions are examined.
MORPHOLOGICAL AND PALEOECOLGICAL ANALYSIS OF THE ORDOVICIAN ANKYROID LAGYNOCYSTIS (STYLOPHORA: ECHINODERMATA)

Abstract Despite its atypical thecal plate pattern, Lagynocystis pyramidalis (Jaekel, 1918) (Middle Ordovician, Northern Gondwanaland) is composed of normally positioned marginal plates on the left side of the theca, whereas those on the right side are shortened or missing in comparison with marginal plates of other ankyroids. The only somatic on the lower thecal surface is the CS plate. The abnormally long distal aulacophore, reduced theca, and internal ctenoid organ are interpreted as adaptations to deep water, dysaerobic environmental conditions. Ctenoid organ morphology is re-evaluated and is interpreted to have both feeding and respiratory functions. Loss of plates relative to a presumed ancestor similar to Barrandeocarpus has resulted in torsion that places somatic platelets, originally on the superior face, onto the inferior face and in contact with both CS and M'3 plates.
Results with the Visscher-Bowman pregnancy test

Abstract 1. Three hundred ninety-five urines were tested by the Visscher-Bowman method for the determination of pregnancy. Correct reactions were obtained in 84.8 per cent of 250 known pregnancies, 87.6 per cent of 65 suspected pregnancies, and 54.8 per cent of 62 nonpregnancies. 2. Urines of low specific gravity or containing unusual amounts of catabolic reducing agents tend to give false reactions. 3. The test in its present form is subject to too high a percentage of error to replace the Friedman and Aschheim-Zondek tests.
A Maximum Likelihood Method for Reconstruction of the Evolution of Eukaryotic Gene Structure

Spliceosomal introns are one of the principal distinctive features of eukaryotes. Nevertheless, different large-scale studies disagree about even the most basic features of their evolution. In order to come up with a more reliable reconstruction of intron evolution, we developed a model that is far more comprehensive than previous ones. This model is rich in parameters, and estimating them accurately is infeasible by straightforward likelihood maximization. Thus, we have developed an expectation-maximization algorithm that allows for efficient maximization. Here, we outline the model and describe the expectation-maximization algorithm in detail. Since the method works with intron presence-absence maps, it is expected to be instrumental for the analysis of the evolution of other binary characters as well.
Sallengre, La Monnoye, and the Traité des trois imposteurs

The edition of the Traite des trois imposteurs published in Amsterdam in 1777 and republished by Retat1 consists of four texts: the Traite,La Monnoye’s ‘Dissertation sur le livre intitule des trois Imposteurs’, an anonymous ‘Reponse a la Dissertation de M. de la Monnoye’2, and a note, purporting to be a copy of the Memoires de litterature, Vol. 1, Pt 2, Art. IX.3 This confirms the existence of the Traite but explains that it is clearly a modern, and not an ancient work, not only because it mentions Descartes but because it is based on the principles of the modern philosophy,4 introduced in the previous century by ‘the Descartes’s, the Gassendis, the Berniers and some others.’5
Forces Acting on Sessile Droplet on Inclined Surfaces

Although many analytical, experimental and numerical studies have focused on droplet motion, the mechanics of the droplet while still in its static state, and just before motion starts, are not well understood. A study of static droplets would shed light on the threshold voltage (or critical inclination) for initiating electrically (or gravitationally) induced droplet motion. Before the droplet starts to move, the droplet shape changes such that the forces acting at the triple contact line balance the actuation forces. These contact line forces are governed by the contact angles along the contact line. The contact angle varies from an advancing angle at the leading edge to a receding angle at the trailing edge of the droplet. The present study seeks to understand and predict these forces at the triple contact line. The droplet shape, as well as the advancing and receding contact angles, is experimentally measured as a function of droplet size under the action of a gravitational force at different inclination angles. The advancing and receding contact angles are correlated with static contact angle and Bond number. A Volume of Fluid - Continuous Surface Force model with varying contact angles along the triple contact line is developed to predict the same. The model is first verified against a two-dimensional analytical solution. It is then used to simulate the shape of a sessile droplet on an incline at various angles of inclination and to determine the critical angle of inclination as a function of droplet size. Good agreement is found between experimental measurements and predictions. The contact line profile and contact area are also predicted. The contact area predictions based on a spherical-cap assumption are also compared against the numerical predictions.Copyright © 2009 by ASME
Measurement and Correlation of Indices of Insulin Resistance in Patients on Peritoneal Dialysis.

BackgroundInsulin resistance (IR) is common in maintenance dialysis patients and is associated with excess mortality. Hyperinsulinemic euglycemic glucose clamp (HEGC) is the gold standard for measu...
Adsorption of monolayers of P2Mo18O626- and deposition of multiple layers of Os(bpy)32+-P2Mo18O626- on electrode surfaces

The unusually strong, irreversible adsorption of monolayer quantities of the P2Mo18O626- anion on glassy carbon, highly ordered pyrolytic graphite, indium tin oxide, and gold-coated quartz electrodes was examined by electrochemical, spectroelectrochemical, and quartz crystal microgravimetric techniques. A very simple method was developed to deposit multiple layers of composites consisting of alternating layers of the P2Mo18O626- anion and large, multiply-charged cations such as Os(bpy)32+. The resulting deposit is stable and exhibits electroactivity from both of the components that reflects the structure and ionic conductivity of the solid multilayer.
Observation of quantum tunneling between two plasmonic nanoparticles.

The plasmon resonances of two closely spaced metallic particles have enabled applications including single-molecule sensing and spectroscopy, novel nanoantennas, molecular rulers, and nonlinear optical devices. In a classical electrodynamic context, the strength of such dimer plasmon resonances increases monotonically as the particle gap size decreases. In contrast, a quantum mechanical framework predicts that electron tunneling will strongly diminish the dimer plasmon strength for subnanometer-scale separations. Here, we directly observe the plasmon resonances of coupled metallic nanoparticles as their gap size is reduced to atomic dimensions. Using the electron beam of a scanning transmission electron microscope (STEM), we manipulate pairs of ∼10-nm-diameter spherical silver nanoparticles on a substrate, controlling their convergence and eventual coalescence into a single nanosphere. We simultaneously employ electron energy-loss spectroscopy (EELS) to observe the dynamic plasmonic properties of these di...