cssi/SciSciGPT-SciSciNet huggingface dataset:
Programming for different memory consistency models

Abstract The memory consistency model, or memory model, supported by a shared-memory multiprocessor directly affects its performance. The most commonly assumed memory model is sequential consistency (SC). While SC provides a simple model for the programmer, it imposes rigid constraints on the ordering of memory accesses and restricts the use of common hardware and compiler optimizations. To remedy the shortcomings of SC, several relaxed memory models have been proposed in the literature. These include processor consistency (PC), weak ordering (WO), release consistency (RCsc/RCpc), total store ordering (TSO), and partial store ordering (PSO). While the relaxed models provide the potential for higher performance, they present a more complex model for programmers when compared to SC. Our previous research has addressed this tradeoff by taking a programmer-centric approach. We have proposed memory models (DRF0, DRF1, PL) that allow the programmer to reason with SC, but require certain information about the memory accesses. This information is used by the system to relax the ordering among memory accesses while still maintaining SC for the programmer. Our previous models formalized the information that allowed optimizations associated with WO and RCsc to be used. This paper extends the above approach by defining a new model, PLpc, that allows optimizations of the TSO, PSO, PC, and RCpc models as well. Thus, PLpc provides a unified programming model that maintains the ease of reasoning with SC while providing for efficiency and portability across a wide range of proposed system designs.
Mechanisms of Transcriptional Inhibition and Induction by Environmental Mutagens

Abstract Exposure of cells to environmental mutagens activates cellular responses, leading to a reprogramming of gene expression by mechanisms that are not fully elucidated. To investigate the mechanisms of how environmental mutagens affect global gene expression in human cells both at the level of RNA synthesis and transcript stability, we developed a new technique, called BruChase-Seq, based on bromouridine (BrU) pulse-chase labeling coupled to deep sequencing. Using BruChase-Seq we found that ionizing radiation, cadmium or the pro-inflammatory cytokine TNF rapidly altered both the synthesis and the transcript stability of specific sets of genes in human fibroblasts. To directly assess the effect of UV light on nascent RNA transcription, we developed BrUV-Seq, where cells are irradiated with UV-light immediately before labeling nascent RNA with BrU. We found that UV-induced DNA lesions inhibited transcription elongation but not initiation, leading to a dramatic enhancement of sequencing signal at trans...
Root locus approach to a distributed parameter vibrating system with both bending and torsion motions

Abstract In this work, root locus technique is used to study the active damping effects of a flexible structure governed by Euler—Bernoulli model including both bending and torsion motions. Two force actuators and three moment actuators are located at the beam tip (antenna), together with five rate sensors. It is found that with sufficiently large gain, at most, the vibration corresponding to the first five frequencies (ω1, …, ω5) can be completely eliminated, and none of the other frequencies can possibly be eliminated. These five frequencies correspond to two bending modes in the x-z plane, two bending modes in the y-z plane and one torsion mode. The root locus indicates that while active damping is effective only to low frequency vibrations, it excites all other modes even if only one mode is involved initially. Finally, the sensor noise rejection phenomenon is studied and it is found that the beam tip torsion motion completely rejects any zero-average periodic disturbance with period 2L/c, where L is the beam length and c is certain constant depending upon the beam material.
Numerical codes for cylindrical general relativistic systems.

Abstract Various numerical methods for solutions of Einstein equations are presented and discussed. The numerical schemes are classified according to the equations (evolution versus constraint) solved and according to the coordinate conditions used. The numerical methods are compared by using them to study systems with cylindrical symmetry for vacuum (Einstein-Rosen waves), matter collapse, and cosmology (perturbation of Friedmann Universe).
Gastrointestinal helminths from fifteen species of Litoria and Nyctimystes (Anura: Hylidae) from Papua New Guinea.

Three hundred and ninety‐nine individuals representing 10 species of Litoria and five species of Nyctimystes (Hylidae), L. arfakiana, L. bibonius, L. eucnemis, L. genimaculata, L. impura, L. infrafrenata, L. modica, L. nasuta, L. thesaurensis, L. wollastoni, N. gularis, N. kubori, N. papua, N. pulcher and N. semipalmatus collected in Papua New Guinea were examined for helminths. Gravid individuals representing one species of Monogenea (Parapolystoma bulliense), one species of Digenea (Mesocoelium monas), 18 species of Nematoda (Aplectana krausi, Aplectana macintoshi, Aplectana zweifeli, Cosmocerca novaeguineae, Falcaustra papuensis, Icosiella papuensis, Maxvachonia adamsoni, Maxvachonia ewersi, Meteterakis crombiei, Moaciria moraveci, Ochoterenella papuensis, Oswaldocruzia bakeri, Parapharyngdon maplestoni, Parathelandros allisoni, Parathelandros andersoni, Physalopteroides milnensis, Rhabdias australiensis, Seuratascaris numidica) and one species of Acanthocephala (Acanthocephalus bufonis) were found. Al...
Reaction of Spanish-Type Peanut Genotypes to Cylindrocladium Black Rot1

Abstract Twelve peanut (Arachis hypogaea L.) genotypes of the Spanish botanical type and two of the Valencia botanical type were compared for reaction to the soil-borne pathogen, Cylindrocladium cr...
SU-FF-J-107: Extraction of Internal and External Marker 3D-Motion in Liver Patients with Compression Belt Using KV Cone-Beam Radiographic Projections

Purpose: To study correlation of internal implanted vs. external skin markers for tracking respiratory motion in liver patients using radiographic projections from on‐board kV cone‐beam scans. Material and Method: Cone‐beam projections were analyzed to extract 3D‐motion of internal and external markers for five liver patients receiving hypofractionated radiotherapy. Patients were immobilized in a stereotactic body frame and an abdominal compression belt was used to constrain respiratory motion. Marker motion was derived using a tracking algorithm and analysis of a sequence of 650 cone‐beam projections acquired during a 1 minute scan. Corrections were made for imager rotation and sag. Results: External and internal markers had the same frequency of respiratory motion, however, the amplitude of external marker motion is smaller. Internal and external marker motion was also out‐of‐phase in some patients. Internal marker motion is greater in the superior‐inferior direction than in anterior‐posterior and right‐left directions, which is due to compression belt constraining of respiratory motion in these direction. Two patients showed small or no motion of the external marker, whereas, internal marker motion was as large as 1.0 cm, which may be due to the proximity of the external marker to the compression belt. Conclusions: Although, the motions of internal and external markers are usually correlated and have similar motion frequency, the amplitude of marker motion may differ significantly and in some patients markers may move our‐of‐phase. The abdominal compression belt suppresses respiratory motion strongly normal to patient skin and may contribute to phase differences. The external markers motion for monitoring internal changes of respiration should be used with caution. Marker 3D‐motion from cone‐beam projections provides real time tumor trajectory that can be used to determine accuracy of PTV margins with no extra dose other than that used in CBCTimaging.Conflict of Interest: Supported by NCI Grant P01‐CA59017.
Ten weeks of intermittent hypocalcemic stimulation does not produce functional parathyroid hyperplasia.

ABSTRACT Hypocalcemia is a major stimulus for parathyroid hormone secretion and presumably the major cause of parathyroid hyperplasia in chronic hypocalcemic syndromes. We could find no data to indicate what degree, duration, or frequency of hypocalcemia is needed to produce parathyroid hyperplasia in humans. We have monitored the effects of thrice weekly hypocalcemic parathyroid stimulation for 10 weeks. Measurements were made during a study designed to test the feasibility of carrying out a randomized, blinded trial of "chelation therapy," a widely used but unproven method to treat atherosclerotic symptoms. Eight patients received infusions of disodium ethylenediaminetetraacetic acid (EDTA) and six received placebo infusions thrice weekly for ten weeks. The EDTA infusions (50 mg/kg over three hours) lowered serum ionized calcium at two hours by an average of 0.20 mmol/L and trebled the immunoreactive parathyroid hormone (iPTH) value. Basal serum iPTH, ionized calcium and 1,25-dihydroxy vitamin D values, measured just before the infusion, did not change significantly after 10 weeks of treatment with either EDTA or placebo. The increment in serum iPTH produced by the EDTA-induced hypocalcemia was also unchanged. Lowering ionized serum calcium to values below the normal range three times a week for 10 weeks is not a sufficient stimulus to cause a detectable increase in basal or stimulated parathyroid function.
Foundations, lessons, and insider tips for MSR research

Any new field of inquiry struggles with issues such as domain uniqueness, research methodologies, construct definition and operationalization, and foundational literature identification. Following Hambrick's (1990) seminal study of strategic management, we similarly examine the management, spirituality, and religion (MSR) field. Using Hambrick's methodology for citation analysis and a dataset of the founding decade of MSR empirical articles, we offer a guide for those doing MSR research. Study outcomes include the 50 most cited MSR works, the 50 most cited journals that MSR scholars use as the foundation of their research, and a theme analysis of the 50 foundational works. Our goals are threefold: to list the seminal works that should inform the framing of future work, to list a variety of possible MSR journal scholarship inspirations and outlets, and to empirically demonstrate current and past MSR research topics so new and experienced MSR scholars can move beyond extant work.
Designing project-based instruction to foster generative and mechanistic understandings in genetics

The acquisition of scientific knowledge is fraught with difficulties and challenges for the learner. The very nature of some scientific domains contributes to the learning difficulties students' experience. Phenomena in these domains are composed of multiple organization levels featuring complicated interactions within and across these levels. Molecular genetics is a compelling example of such a domain. Current instructional practices in genetics leave students ill prepared to benefit from technological advances in genetics or to participate in public discussions about genetic issues. We argue that instruction in genetics needs to be refocused such that it promotes generative understandings of the genetic mechanisms that are at the core of modern genetics. This paper presents the early stages of design-based research involving the development and study of a curriculum unit in genetics for high school students. We employed several design strategies to make the structure and mechanisms of genetic phenomena salient in the activities of the unit. Our findings suggest that the curriculum does, to a large extent, engender a deeper understanding of genetic phenomena. Specifically, we observed gains in students' understanding of the genetic information and the mechanisms that link genes to traits. © 2010 Wiley Periodicals, Inc. Sci Ed95: 21–56, 2011
On Convergence of Kronecker Graphical Lasso Algorithms

This paper studies iteration convergence of Kronecker graphical lasso (KGLasso) algorithms for estimating the covariance of an i.i.d. Gaussian random sample under a sparse Kronecker-product covariance model and MSE convergence rates. The KGlasso model, originally called the transposable regularized covariance model by Allen [“Transposable regularized covariance models with an application to missing data imputation,” Ann. Appl. Statist., vol. 4, no. 2, pp. 764–790, 2010], implements a pair of $\ell_1$ penalties on each Kronecker factor to enforce sparsity in the covariance estimator. The KGlasso algorithm generalizes Glasso, introduced by Yuan and Lin [“Model selection and estimation in the Gaussian graphical model,” Biometrika, vol. 94, pp. 19–35, 2007] and Banerjee [“Model selection through sparse maximum likelihood estimation for multivariate Gaussian or binary data,” J. Mach. Learn. Res., vol. 9, pp. 485–516, Mar. 2008], to estimate covariances having Kronecker product form. It also generalizes the unpenalized ML flip-flop (FF) algorithm of Dutilleul [“The MLE algorithm for the matrix normal distribution,” J. Statist. Comput. Simul., vol. 64, pp. 105–123, 1999] and Werner [“On estimation of covariance matrices with Kronecker product structure,” IEEE Trans. Signal Process., vol. 56, no. 2, pp. 478–491, Feb. 2008] to estimation of sparse Kronecker factors. We establish that the KGlasso iterates converge pointwise to a local maximum of the penalized likelihood function. We derive high dimensional rates of convergence to the true covariance as both the number of samples and the number of variables go to infinity. Our results establish that KGlasso has significantly faster asymptotic convergence than Glasso and FF. Simulations are presented that validate the results of our analysis. For example, for a sparse 10 $\thinspace$ 000 $\,\times\,$ 10 $\thinspace$ 000 covariance matrix equal to the Kronecker product of two 100 $\,\times\,$ 100 matrices, the root mean squared error of the inverse covariance estimate using FF is 2 times larger than that obtainable using KGlasso for sample size of $n=100$ .
CONVEX AND CONCAVE SURFACE CURVATURE EFFECTS IN WALL-BOUNDED TURBULENT FLOWS

A fully ellipitic numerical method developed to solve the two-dimensional Reynolds-averaged Navier-Stokes equations for an incompressible fluid is employed in a computational study of several flows involving convex and concave surface curvature. The K-epsilon turbulence model and variant of it, proposed to improve the calculation of flows with streamline curvature, are used in conjunction with a one-equation near-wall model. The performance of the method is examined through computations of fully developed curved duct flow and boundary layers on curved surfaces. In each case the main features of the flow are consistently reproduced. However, the computations tend to overpredict the convex wall skin friction and underpredict the concave wall skin friction.
THE CORRELATES OF SAT TEST SCORES AND SELF REPORTED INCOME ON THE STUDENT DESCRIPTIVE QUESTIONNAIRE

Some of the the social functions of testing were examined by studying the characteristics and educational outcomes of students with different test scores and from families with different incomes. Using SAT-SDQ file information, the educational plans and other relevant characteristics of students with different combinations of family income and test scores were compared. A follow-up of applicants who had completed high school in 1981 determined their educational status. These data were related to the applicants' test scores and family incomes to estimate the relative influence of each on their educational outcomes.
Use of Rotating Pinholes and Reticles for Calibration of Cloud Droplet Instrumentation

Calibration devices for the Forward Scattering Spectrometer Probe (FSSP) and the Optical Array Probe (OAP) were developed. The device used with the FSSP is a rotating pinhole calibrator. It utilizes light diffracted by a pinhole of a known diameter to simulate scattered light from a water droplet. This device can be used to calibrate the FSSP, measure the FSSP's optical collection angles and for instrument alignment and troubleshooting. The device used with the OAP is a rotating reticle calibrator. Chrome disks of a known diameter on the reticle are used for calibration of the OAP and for determining the OAP's response to out-of-focus particles in the probe volume.
Breeding for organic and low-input farming systems: An evolutionary-participatory breeding method for inbred cereal grains

Organic and low-input farmers often plant seed varieties that have been selected under conventional practices, traditionally including high inputs of artificial fertilizers, crop protection chemicals and/or water. In addition, these crops are often selected in environments that may or may not represent the local environment of the farmer. An evolutionary participatory breeding (EPB) method emphasizes the utilization of natural selection in combination with site-specific farmer selection in early segregating generations of a heterogeneous crop population. EPB is a combination of two specific breeding methods, evolutionary breeding and participatory plant breeding. Evolutionary breeding has been shown to increase yield, disease resistance, genetic diversity and adaptability of a crop population over time. It is based on a mass selection technique used by farmers for over 10,000 years of crop improvement. Participatory plant breeding programs originated in developing countries to meet the needs of low-input, small-scale farmers in marginal environments who were often overlooked by conventional crop breeders. The EPB method is an efficient breeding system uniquely suited to improving crop varieties for the low-input and organic farmer. The EPB method utilizes the skills and knowledge of both breeders and farmers to develop heterogeneous landrace populations, and is an effective breeding method for both traditional and modern farmers throughout the world.
Transient thermal protection of film covering circular aperture by sublimation and weak decomposition

Abstract Unwanted heating of sensitive surfaces in harsh thermal environments can be prevented by precise application of sacrificial materials such as sublimation layers and pyrolyzing films. The use of sublimation for the protection of circular polyimide membranes subjected to brief (∼100 ms) heating by infrared radiation and hot (6000 K) inert gas convection is analyzed. Selection of sublimation material and sublimation layer and membrane thickness is considered with emphasis on providing sufficient thermal protection yet negligible unwanted material remaining at the end of a specified heating period. Though the analysis here is general, the motivation is protection of the polyimide films covering the laser entrance holes on IFE (inertial fusion energy) hohlraums being injected into the hot gas (xenon) protecting IFE reactor chambers. Both one and two dimensional thermal models are used to develop a robust thermal concept. Sensitivity analyses (SA) methods are exercised to show where the design may be vulnerable and which input parameters have the greatest effect on performance and likelihood of success. For the design and conditions considered, methane sublimating layers are probably preferred over xenon or pentane.
Training employees to work in the Mid East safely

Offers some direction to the potential expatriate employee destined for any Middle Eastern country. Addresses issues such as personal safety and that of any accompanying family in addition to advice on moving and settling in. Gives details of support and help that can be employed. Concludes that as the culture differences with the West are so huge, only preparedness and thorough understanding based on cultural background will really support the individual.
What Kind of Community is the Church?: The Richard Hooker Lectures 2005

As our practical reason is healed in the resurrection life of Christ, there may be a community in which many agents act as one. Yet there is a difficulty in understanding the idea of a community of action; and in the first of these two Richard Hooker lectures I explore this difficulty, in pursuit of an answer to the question: Can the Church be a moral community? And can such a community be a forum in which questions are actually resolved? This takes us on to the question of the second lecture: Is the Church a community under authority ? The Church's form may be described in terms of a tension between an outer and an inner identity. How does the inner identity of the Church come to shape its outer forms? It does so through the acknowledgment of Scripture , which judges, corrects, criticizes the practices of the Church, and as the message heard in Scripture and the doctrine formed in reflection on it is taken into its practical reasoning.
A controlled boundary theorem for Hilbert cube manifolds

Abstract In this paper a boundary theorem for Hilbert cube manifolds is established,where it is required that the boundary be put on the manifold with arbitrarily small control in a given compact metric parameter space.
Vascular endothelial growth factor receptor 2 mediates macrophage infiltration into orthotopic pancreatic tumors in mice

Macrophages are an abundant inflammatory cell type in the tumor microenvironment that can contribute to tumor growth and metastasis. Macrophage recruitment into tumors is mediated by multiple cytokines, including vascular endothelial growth factor (VEGF), which is thought to function primarily through VEGF receptor (VEGFR) 1 expressed on macrophages. Macrophage infiltration is affected by VEGF inhibition. We show that selective inhibition of VEGFR2 reduced macrophage infiltration into orthotopic pancreatic tumors. Our studies show that tumor-associated macrophages express VEGFR2. Furthermore, peritoneal macrophages from tumor-bearing animals express VEGFR2, whereas peritoneal macrophages from non-tumor-bearing animals do not. To our knowledge, this is the first time that tumor-associated macrophages have been shown to express VEGFR2. Additionally, we found that the cytokine pleiotrophin is sufficient to induce VEGFR2 expression on macrophages. Pleiotrophin has previously been shown to induce expression of endothelial cell markers on macrophages and was present in the microenvironment of orthotopic pancreatic tumors. Finally, we show that VEGFR2, when expressed by macrophages, is essential for VEGF-stimulated migration of tumor-associated macrophages. In summary, tumor-associated macrophages express VEGFR2, and selective inhibition of VEGFR2 reduces recruitment of macrophages into orthotopic pancreatic tumors. Our results show an underappreciated mechanism of action that may directly contribute to the antitumor activity of angiogenesis inhibitors that block the VEGFR2 pathway.
Holocene soil-geomorphic surfaces influence the role of salmon-derived nutrients in the coastal temperate rainforest of Southeast Alaska

Abstract The influence of salmon-derived nutrients (SDN) is widely accepted as a potential factor in the maintenance of aquatic and terrestrial productivity in North American Coastal rainforests. Holocene alluvial landforms are intimately connected with the return of anadromous salmon, but the influence of the soils that occupy these landforms and support this important terrestrial–aquatic ecological coupling have not been examined in SDN studies. We used paleo-ecologic information, soil resource inventories and measurements of soil morphology to construct a soil-geomorphic model for alluvial landforms along salmon spawning channels on Prince of Wales Island, Southeast Alaska, USA. Post-glacial sea-level rise, crustal uplift and subsidence combined with Holocene sediment deposition have formed alluvial terraces and floodplains along rivers on Prince of Wales Island. These alluvial landforms have soils that are mapped as Entisols (Tonowek soil series) and Spodosols (Tuxekan soil series). We propose a soil-geomorphic model where the Spodosols located on terraces are estimated to derive from sediments deposited after the stabilization of landscape approximately 8 kybp to 6 kybp. The stability of these soils is reflected through mature soil development with organic matter accumulation and podzolization. Our model identifies Entisols on floodplains developed from alluvial deposition in the latter Holocene that have soil morphologic features consistent with recent deposition and limited soil development. We used this soil-geomorphic model to test the hypothesis that the terrestrial end-member value commonly used to quantify nitrogen (N) loading on soils through stable isotope analysis differs by soil type and found that the two soil types had significantly different N isotopic (δ15N) values more consistent with soil development than SDN loading. The use of a soil-geomorphic model provides a means to stratify alluvial landforms and constrain the natural variability encountered in studies of riparian nutrient cycles associated with the feedbacks between SDN and terrestrial ecosystems to improve estimates of the fate of SDN in soils and vegetation.
Coincident Activation of NMDA and Dopamine D1Receptors within the Nucleus Accumbens Core Is Required for Appetitive Instrumental Learning

The nucleus accumbens, a brain structure ideally situated to act as an interface between corticolimbic information-processing regions and motor output systems, is well known to subserve behaviors governed by natural reinforcers. In the accumbens core, glutamatergic input from its corticolimbic afferents and dopaminergic input from the ventral tegmental area converge onto common dendrites of the medium spiny neurons that populate the accumbens. We have previously found that blockade of NMDA receptors in the core with the antagonist 2-amino-5-phosphonopentanoic acid (AP-5; 5 nmol) abolishes acquisition but not performance of an appetitive instrumental learning task (Kelley et al., 1997). Because it is currently hypothesized that concurrent dopamine D(1) and glutamate receptor activation is required for long-term changes associated with plasticity, we wished to examine whether the dopamine system in the accumbens core modulates learning via NMDA receptors. Co-infusion of low doses of the D(1) receptor antagonist SCH-23390 (0.3 nmol) and AP-5 (0.5 nmol) into the accumbens core strongly impaired acquisition of instrumental learning (lever pressing for food), whereas when infused separately, these low doses had no effect. Infusion of the combined low doses had no effect on indices of feeding and motor activity, suggesting a specific effect on learning. We hypothesize that co-activation of NMDA and D(1) receptors in the nucleus accumbens core is a key process for acquisition of appetitive instrumental learning. Such an interaction is likely to promote intracellular events and gene regulation necessary for synaptic plasticity and is supported by a number of cellular models.
Biomedical engineering research strategies in the US

The socioeconomic and political climates influencing biomechanical engineering research in the United States are discussed. The many factors that influence the research environment, strategies, and directions in the United States are also discussed. The roles of the National Institutes of Health (NIM) and the National Science Foundation (NSF) in supporting biomedical engineering are reviewed. Since the strategies of such agencies have an impact on the directions individual investigators take in their own research programs, some of the specific areas identified as priorities by NIH and NSF are examined. >
Directional Bias in the Perception of Translating Patterns

Recent findings suggest that the visual system is biased by its past stimulation to detect one direction of motion over others. Three experiments were designed to investigate whether this bias is mediated by the direction or by the velocity of the past stimulation, and whether this bias is offset by contradictory pattern or depth information. Observers were presented with two solid or random-dot patterns that moved across a display screen in antiphase. As the two patterns reached the center of the screen, they became superimposed in such a way that their subsequent directions were ambiguous. Results from experiment 1 showed that the probability of perceiving these patterns as continuing to move in the same directions was significantly greater when they moved at a constant velocity than when they moved at a variable velocity. Results from experiments 2 and 3 revealed that this directional bias was reversed only gradually as an increasing amount of contradictory pattern information was introduced, but that this reversal was quite abrupt when a relatively small amount of contradictory depth information was introduced. Collectively, these results suggest that a directional bias in the perception of moving patterns is mediated not only by the direction of the previous stimulation, but also by the velocity of that stimulation. Moreover, the analyses of pattern and motion information appear relatively independent during the early stages of visual processing, but the analyses of depth and motion information appear considerably more interdependent.
A filter based bit allocation scheme for subband compression of HDTV

The authors compare the subband compression capabilities of eight filter sets (consisting of linear-phase quadrature mirror filters (QMFs), perfect reconstruction filters, and nonlinear phase wavelets) at different bit rates, using-a filter-based bit allocation procedure. Using DPCM and PCM in HDTV subband coding, it is found that QMFs have an edge over the rest. >
Incipient speciation with biased gene flow between two lineages of the Western Diamondback Rattlesnake (Crotalus atrox).

We used mitochondrial DNA sequence data from 151 individuals to estimate population genetic structure across the range of the Western Diamondback Rattlesnake (Crotalus atrox), a widely distributed North American pitviper. We also tested hypotheses of population structure using double-digest restriction site associated DNA (ddRADseq) data, incorporating thousands of nuclear genome-wide SNPs from 42 individuals. We found strong mitochondrial support for a deep divergence between eastern and western C. atrox populations, and subsequent intermixing of these populations in the Inter-Pecos region of the United States and Mexico. Our nuclear RADseq data also identify these two distinct lineages of C. atrox, and provide evidence for nuclear admixture of eastern and western alleles across a broad geographic region. We identified contrasting patterns of mitochondrial and nuclear genetic variation across this genetic fusion zone that indicate partially restricted patterns of gene flow, which may be due to either pre- or post-zygotic isolating mechanisms. The failure of these two lineages to maintain complete genetic isolation, and evidence for partially-restricted gene flow, imply that these lineages were in the early stages of speciation prior to secondary contact.
A simulation study on multi-rate mobile ad hoc networks

This paper studies the performance of a multi-rate mobile ad hoc network (MANET) using an extended ns-2 simulator. A link adaptation algorithm is developed and tested. The multi-rate control algorithm is based on the channel access mechanism for IEEE 802.11 with modifications. Some realistic models for radio propagation, such as lognormal fading and Walfisch/Ikagami propagation model, are used. At transport and application layer, different kinds of data traffic, including constant bit rate, TCP, voice over IP, and video are tested. The effects due to position error and mobility are also examined. The simulation results show that link layer data rate control can greatly improve network performance. Components at different layers all contribute to the system performance of a MANET. It is also shown that multimedia data transmission over MANETs deserves future study.
Family Context Therapy: A Model for Family Change*

Starting where family group therapy fails, this article breaks new territory in family context therapy. Consolidating the past 14 years of his work, Dr. Bell sets forth a conceptual program and methods to meet problems that earlier forms of family therapy could not reach. Here he provides a model drawn from studies, theories, and personal experience of organizational patterns, interrelations, and change among community institutions that provide settings for family functioning. His new methods are designed to modify the family environment so as to solve family problems and promote beneficial family growth—a framework that may bring together a broad variety of existing family development approaches.
Effect of the general anesthetic halothane on the activity of the transverse tubule Ca2+-activated K+ channel

The effect of the general anesthetic halothane on the activity of the rat skeletal muscle Ca(2+)-activated K+ channel in planar lipid bilayers was investigated. Halothane concentrations in the clinical range (1.0-0.2 mM) alter the regulation of the channel by both Ca2+ and membrane potential. At Ca2+ concentrations between 10 and 250 microM and membrane potentials between 0 and -30 mV, halothane significantly decreases the open state probability without changing the channel conductance. The results demonstrate that halothane can act directly on the Ca(2+)-activated K+ channel or its lipid environment to alter the channel gating kinetics.
Commentary: Binding Early Offers versus Caps for Medical Malpractice Claims?

Like damages caps, early offer reform promises reduction in the costs of medical liability cases. In contrast to damages caps, early offer reform offers advantages to both claimant and defendant. Under early offer, the defendant would have the option to offer an injured patient periodic payments for the patient's net economic losses as they accrue, but not payments for noneconomic losses (pain and suffering). If an early offer were made and accepted, that would settle the claim. This commentary1 explains how an early offer reform might work and summarizes data from a recent closed claim study of medical malpractice cases in Texas and Florida. The data show widespread opportunities for successful early offers and provide evidence that substantial per case savings would result.
Diatom ecology and microbial mat structure and function in Antarctic Dry Valleys

Streams in the McMurdo Dry Valleys of Antarctica (MDV) are harsh habitats for life. Months of perpetual darkness and subzero temperatures are punctuated by months of perpetual sunlight, intense UV radiation, and temperatures that hover around freezing. The availability of liquid water regulates biological activity and limits the growing season to 6–10 weeks each year. These harsh conditions likely allow perennial microbial mats to persist in this freshwater environment (Fig. 1), as the rates of biomass accumulation exceed losses due to grazing metazoans and scouring (McKnight and Tate, 1997). FIGURE 1— Harnish Creek Tributary in the McMurdo Dry Valleys of Antarctica. A) Glacial meltwater flows into stream channels that drain into closed-basin lakes on the valley floors. The unconsolidated sediments in this image represent much of the ground surface, while a stable stone pavement is found in numerous stream channels, which results from freeze-thaw action over many years. Large seepage areas and a wide hyporheic zone develop as meltwater infiltrates the unconsolidated sediment. B) Close-up of area. C) Vibrant black and orange colors are UV-protective pigments produced by filamentous cyanobacteria, which form the matrix. Gas bubbles within the microbial mat demonstrate the high photosynthetic rates that can be achieved. Photo credit: Breana Simmons. Despite the extreme selective conditions, MDV microbial mats harbor a diverse diatom flora. Diatoms comprise a large lineage of eukaryotic algae that are broadly distributed in aquatic habitats and contribute significantly to global primary productivity (Treguer et al., 1995; Field et al., 1998). Their cell walls, or frustules, are constructed out of biogenic silica (SiO2), which can persist as a biosignature in sediments and the rock record for millions of years (Kooistra et al., 2007). The morphology of the frustule is generally species specific and is, therefore, relied upon for taxonomic identification, although cryptic species do exist (Beszteri …
Automatic decentralized clustering for wireless sensor networks

We propose a decentralized algorithm for organizing an ad hoc sensor network into clusters. Each sensor uses a random waiting timer and local criteria to determine whether to form a new cluster or to join a current cluster. The algorithm operates without a centralized controller, it operates asynchronously, and does not require that the location of the sensors be known a priori. Simplified models are used to estimate the number of clusters formed, and the energy requirements of the algorithm are investigated. The performance of the algorithm is described analytically and via simulation.
Effects of weekly thyroxine administration on serum thyroxine, 3,5,3'-triiodothyronine, thyrotropin, and the thyrotropin response to thyrotropin-releasing hormone.

Once weekly administration of T4 to normal subjects was used to suppress pituitary TSH secretion. In four euthyroid subjects, 1.5 mg T4/week were given for 4 weeks. Seven days after each dose of T4, serum T4 was not significantly different from the baseline value, although at two intervals, serum Ta was modestly but significantly increased over the basal value. Serum TSH was suppressed to less than 0.5 μU/;ml throughout the period of T4 administration. A bolus of 500 μg TRH 3 weeks after the last dose of T4 resulted in TSH release which was identical in quantity to that found before T4 administration. A TRH infusion of 1 μg/;min for 7 h on the next day resulted in an increase in TSH to 6 μU/ml, where it remained throughout the period of the infusion. Serum T3 concentrations increased both after the 500-μg TRH test and after the 7-h infusion. Mean serum T4 was 1.3-1.6 μg/dl higher during the sixth and seventh hours of infusion than at the start of the infusion, and serum T3 increased from 135 to 205 ng/dl....
Molecular cloning and hormonal regulation of a murine epididymal retinoic acid-binding protein messenger ribonucleic acid.

A complementary DNA encoding the mouse epididymal secretory protein MEP 10 (mouse epididymal protein 10) was cloned and is now renamed murine epididymal retinoic acid binding protein (mE-RABP). The analysis of the predicted primary amino acid sequence showed that mE-RABP has a 75% identity with rat ESP I (epididymal secretory protein I), another epididymal retinoic acid-binding protein. The homology strongly suggests that mE-RABP is the mouse orthologue of rat ESP I. A computer analysis of the predicted three-dimensional structure confirmed that mE-RABP can accommodate retinoic acid as ligand. In the rat, ESP I messenger RNA (mRNA) is expressed in the efferent ducts and in the entire caput epididymidis. However, in the mouse, the expression of a 950-bp mE-RABP mRNA was detected only in principal cells of the mid/distal caput epididymidis, suggesting that the regulation of region-specific expression is different in rat and mouse. Northern blot analyses showed that mE-RABP gene expression is no longer detec...
Effect of Creep Damage on the Tensile Creep Behavior of a Siliconized Silicon Carbide

The tensile creep behavior of a siliconized silicon carbide was investigated in air, under applied stresses of 103 to 172 MPa for the temperature range of 1100° to 1200°C. At 1100°C, the steady-state stress exponent for creep was approximately 4 under applied stresses less than the threshold for creep damage (132 MPa). At applied stresses greater than the threshold stress for creep damage, the stress exponent increased to approximately 10. The activation energy for steady-state creep at 103 MPa was approximately 175 kJ/mol for the temperature range of 1100° to 1200°C. Under applied stresses of 137 and 172 MPa, the activation energy for creep increased to 210 and 350 kJ/mol, respectively, for the same temperature range. Creep deformation in the siliconized silicon carbide below the threshold stress for creep damage was determined to be controlled by dislocation processes in the silicon phase. At applied stresses above the threshold stress for creep damage, creep damage enhanced the rate of deformation, resulting in an increased stress exponent and activation energy for creep. The contribution of creep damage to the deformation process was shown to increase the stress exponent from 4 to 10.
Reduction of hysteresis in mobility measurements of carbon nanotube transistors by pulsed I–V characterization

We investigate the effect of pulsed current-voltage (I D -V GS ) measurements on the hysteretic behavior of carbon nanotube field-effect transistors (CNTFET) on SiO 2 , and the subsequent mobility extraction. We find that hysteresis decreases with longer pulse delays and higher ambient temperature, and can be almost entirely eliminated at ~10 s pulse intervals and ~180°C. Moreover, mobility curves extracted in such conditions approach a unified, “true” value for each nanotube, unlike the less reliable conventional methods which rely either on the forward or reverse voltage sweeps.
The Use of Geophysical Logs for Determining Formation Water Quality

In situ water-quality measurements, with respect to various ion and dissolved solids concentrations, have been closely approximated using open-hole borehole geophysical logs. Analyses have shown good correlation between water resistivity (Rw, as determined from the logs) and dominant ion concentrations sampled from a wide range of water quality in Tertiary carbonate and granular formations. Rw can be accurately determined by cross-plotting saturated formation resistivity (Ro), obtained from normal or lateral resistivity logs, against formation bulk porosity from neutron, density, or acoustic velocity logs. Plotting these data on Hingle Resistivity-Porosity Cross Plot (RPCP) paper with the proper matrix cementation factor (m, commonly 1.4 for unconsolidated sands or 1.6 for noncompacted Tertiary carbonates), will yield a graphical solution for Rw based upon the relationship Rw=φm Ro. The graphical technique also provides information concerning water-quality variations with depth, true matric resistivity, location of confining beds, and vertical changes in formation porosity. Once Rw has been determined, other ion concentrations can be estimated based upon chemical analyses of water samples from adjacent wells tapping a similar type water mass (i.e., calcium-bicarbonate, sodium-chloride water, etc.). Total dissolved solids (TDS), chloride, sulfate, potassium, sodium, magnesium, and hardness (as CaCO3) concentrations have consistently shown a high correlation with Rw.
Osmotic and metabolic-induced changes in light scattering of Leishmania donovani as measured by flow cytometry

Leishmania donovani promastigotes were collected from cultures in log and stationary phases of growth and resuspended in Hank's Balanced Salt Solution containing I mM sodium acetate. Changes in the forward and side scattering of the cells were measured by flow cytometry in response to acute changes in osmolality and to the addition of several different substrates. Forward and side scattering of cells from log phase cultures decreased when the osmolality was decreased by the addition of H 2 O and increased when the osmolality was increased by the addition of NaCl. Cells from stationary phase cultures had about the same forward scatter as cells from log phase cultures, but almost a four-fold lower side scatter, and their side scatter values did not change significantly in response to a reduction in osmolality. Microscopic observation showed that both log and stationary cells got longer and thinner, on average, in response to hyperosmolality. The light scattering properties of log (but not of stationary) cells changed in a reproducible manner when substrates were added to the buffer. The ratio of forward to side scatter increased in the following order: controls in balanced salt solution < aspartate < glutamate, glucose or 2-deoxyglucose < alanine < proline. Thus the light scattering properties of L. donovani promastigotes change with culture age, in response to changes in osmolality, and, in log phase cells, in response to the presence of several substrates.
TrueLink: A Practical Countermeasure to the Wormhole Attack in Wireless Networks

In a wormhole attack, wireless transmissions are recorded at one location and replayed at another, creating a virtual link under attacker control. Proposed counter-measures to this attack use tight clock synchronization, specialized hardware, or overhearing, making them difficult to realize in practice. TrueLink is a timing based countermeasure to the wormhole attack. Using TrueLink, a node i can verify the existence of a direct link to an apparent neighbor, j. Verification of a link i harr j operates in two phases. In the rendezvous phase, the nodes exchange nonces alphaj and betai. This is done with tight timing constraints, within which it is impossible for attackers to forward the exchange between distant nodes. In the authentication phase, i and j transmit a signed message (alphaj,betai), mutually authenticating themselves as the originator of their respective nonce. TrueLink does not rely on precise clock synchronization, GPS coordinates, overhearing, geometric inconsistencies, or statistical methods. It can be implemented using only standard IEEE 802.11 hardware with a minor backwards compatible firmware update. TrueLink is meant to be used together with a secure routing protocol. Such protocols require an authentication mechanism, which will also be used by TrueLink. TrueLink is virtually independent of the routing protocol used. Our performance evaluation shows that TrueLink provides effective protection against potentially devastating wormhole attacks.