cssi/SciSciGPT-SciSciNet huggingface dataset:
A Programming Model for Time-Synchronized Distributed Real-Time Systems

Discrete-event (DE) models are formal system specifications that have analysable deterministic behaviors. Using a global, consistent notion of time, DE components communicate via time-stamped events. DE models have primarily been used in performance modeling and simulation, where time stamps are a modeling property bearing no relationship to real time during execution of the model. In this paper, we extend DE models with the capability of relating certain events to physical time. We propose a programming model, called PTIDES (programming temporally integrated distributed embedded systems), which has DE semantics, but with carefully chosen relations between model time and real time. Key to making this model effective is to ensure that constraints that guarantee determinacy in the semantics are preserved at runtime. To accomplish this, we give a distributed execution strategy that obeys DE semantics without the penalty of totally ordered executions based on time stamps. Our technique relies on having a distributed common notion of time, known to some precision. Based on causality analysis of DE models, we define relevant dependency and relevant orders to enable out-of-order execution without compromising determinism and without requiring backtracking
Flotation rates, molecular weights and hydrated densities of the low-density lipoproteins.

A method involving three computer programs is described for characterizing the major component of the Sf 0–12 low-density lipoprotein class by its Sf rate, hydrated density and molecular weight. All necessary information is obtained from a standard low and high-density lipoprotein ultracentrifugal analysis. Moving-boundary flotation rates are measured in 1.061 g/ml sodium chloride and 1.200 g/ml sodium bromide solutions and are corrected to flotation at zero concentration. Hydrated densities are calculated from η Fo versus ρ plots and minimum hydrated molecular weights calculated using Stokes' frictional factor, assuming spherical molecules. Preliminary application of this procedure indicates higher Sfo rates, higher molecular weights, and lower hydrated densities in females than in males. Molecular weights and standard deviations of the principal Sf 0–12 component for non-fasting normal adult females and males were 2.36±0.16 and 2.12±0.20 millions, respectively.
Decreasing overuse of therapies in the treatment of bronchiolitis by incorporating evidence at the point of care.

Abstract Objective To describe the effect of evidence-based point-of-care algorithms and rules, based on guideline recommendations, on the overuse of therapies for bronchiolitis. Study design Pre-postintervention for infants Results A total of 256 patients from 2002 were compared with 1272 historic patients. In 2002, the odds of receiving any bronchodilator, more than 1, more than 2, and more than 4 bronchodilators were all significantly less than predicted by the 1997 to 2001 year-to-year trend. The odds of receiving a nasopharyngeal wash for respiratory syncytial virus and a chest radiography (OR = 0.680, CL = 0.476, 0.973) were also significantly lower than what was predicted from use trends of previous years. Conclusions Evidence-based point-of-care instruments can have a significant effect on unwarranted treatment variation.
New Opportunities for Using Farmland Values in the Analysis of Economic Issues: Discussion

Many people with a wide variety of perspectives are interested in the operation of the farmland market and the value of farmland. Stakeholders in the land, as well as observers, monitor the farmland market to gauge the effects of the physical, economic, and institutional factors affecting farmland values. In the frontier economy that existed years ago, the value of farmland was dependent on its usefulness in food and fiber production. During the past century, land use has expanded to include a variety of other activities. These activities are becoming increasingly important as population increases and technology enhances the natural productivity of the land. In addition, institutional changes may be accompanied by restrictions that may affect land values. Studies of the farmland market and the effects of various factors on farmland values date back to the early development of the agricultural economics profession (Reynolds). Haas examined Minnesota land sales from 1916 to 1919, and Wallace used the 1925 Census of Agriculture data to analyze the variation in Iowa farmland values. Land productivity and land use variables were used in these early studies to explain the variation in farmland values. More recent studies have identified and estimated the effects of many other variables on farmland values (Shi, Phipps, and Colyer). Although no invited/principal paper session on the topic of farmland values has been presented at the American Agricultural Economics Association meetings since the mid 1980s, studies of farmland values continue to be of relevance and interest to the profession (Just and Miranowski, Schmitz). The papers in this session focused on the potential of using data from the USDA's June Agricultural Survey (JAS) in hedonic analyses of regional farmland values, the capitalization of government payments into farmland values, and the potential for separating the effects of environmental characteristics from other determinants of farmland values. All three papers estimated hedonic price functions. The first two use data from the JAS. The third paper uses farmland values and parcel characteristics data from the Economic Research Service's Area Studies Program. In addition to the microdata from these sources, all of the papers use smallarea characteristics data from the Census of Agriculture or from other sources. The mixing of parcel data with small-area (e.g., county) data eliminates some of the variation in the explanatory variables.
Structure of the RXR-RAR DNA-binding complex on the retinoic acid response element DR1.

The 9‐ cis retinoic acid receptor (retinoid X receptor, RXR) forms heterodimers with the all‐ trans retinoic acid receptor (RAR) and other nuclear receptors on DNA regulatory sites composed of tandem binding elements. We describe the 1.70 A resolution structure of the ternary complex of RXR and RAR DNA‐binding regions in complex with the retinoic acid response element DR1. The receptors recognize identical half‐sites through extensive base‐specific contacts; however, RXR binds exclusively to the 3′ site to form an asymmetric complex with the reverse polarity of other RXR heterodimers. The subunits associate in a strictly DNA‐dependent manner using the T‐box of RXR and the Zn‐II region of RAR, both of which are reshaped in forming the complex. The protein–DNA contacts, the dimerization interface and the DNA curvature in the RXR–RAR complex are distinct from those of the RXR homodimer, which also binds DR1. Together, these structures illustrate how the nuclear receptor superfamily exploits conformational flexibility and locally induced structures to generate combinatorial transcription factors.
Laboratory rearing of marine calanoid copepods

Abstract Cohorts of 100 newly hatched ( h ) Pseudocalanus sp. nauplii were reared to maturity in replicate in a flow-through apparatus at 5 ° C and four phytoplankton concentrations (200, 100, 50, and 25 μg carbon · 1 −1 ). The life stage distribution of each cohort was measured by subsampling (nauplii) and silhouette photography (copepodids) at discrete intervals throughout the experimental period to determine the effect of food concentration on cohort development. The flow-through apparatus maintained constant paniculate carbon and nitrogen concentrations during the experiments. Silhouette photography eliminates the need to sacrifice animals so that rearing at field concentrations of copepods was possible. Phytoplankton were grown in chemostats which provided a simple means of maintaining sterile cultures for extended periods and a continual source of cells of constant chemical composition. A stock culture apparatus maintained source populations of copepods with only minimal handling.
Cooperation between STAT3 and c-Jun Suppresses Fas Transcription

Decreased Fas expression during tumor progression often results in a loss of Fas-ligand (FasL)-mediated apoptosis. Human and mouse melanoma exhibit an inverse correlation between the degree of Fas cell surface expression, tumorigenicity, and metastatic capacity. The expression of dominant negative Stat3 or c-Jun in melanoma cells efficiently increased Fas expression and sensitized cells to FasL-induced apoptosis. Stat3+/- as well as c-Jun-/- cells exhibited increased Fas cell surface expression and higher sensitivity to FasL-mediated apoptosis. Suppression of Fas expression by Stat3 and c-Jun is uncoupled from Stat3-mediated transcriptional activation. Our findings indicate that Stat3 oncogenic activities could also be mediated through its cooperation with c-Jun, resulting in downregulation of Fas surface expression, which is implicated in the tumor's ability to resist therapy and metastasize.
CO Oxidation on Pt-Group Metals from Ultrahigh Vacuum to Near Atmospheric Pressures. 2. Palladium and Platinum

CO oxidation on Pd(100), -(111), -(110), and Pt(110) single crystals was studied at steady-state conditions at low (≤2 × 10−3 Torr) and high (2−88 Torr) pressures at various reactant compositions. At low pressures the reaction fell into two regimes, one with a CO-dominant surface where the CO2 formation rate is low, and a second with an O-dominant surface where the reaction rate is high. Within this second regime, the reaction is collision-limited with no oxygen inhibition. Under high-pressure reaction conditions, three reaction regimes are evident: (i) a CO-inhibited metallic regime displaying a low CO2 formation rate; (ii) an oxygen-rich metallic regime with a high CO2 formation rate; and (iii) a high-temperature regime where the CO2 formation rate is either mass transfer limited on a metallic surface or limited by the reduced reactivity of the oxidized surface. The superior activity of Pt group metal oxides compared to the reduced metal, as proposed recently, was not observed in this study.
A retrospective analysis of suspended solids deposition in Onondaga Lake, New York: Composition, temporal patterns, and drivers

Abstract Hurteau CA, Matthews DA, Effler SW. 2010. A retrospective analysis of suspended solids deposition in Onondaga Lake, New York: Composition, temporal patterns, and drivers. Lake Reserv. Manage. 26:43-53. Long-term and seasonal temporal patterns in the deposition of total (TSS), fixed (FSS) and volatile suspended solids (VSS) were documented for eutrophic Ca2 +-rich Onondaga Lake, New York, for the 1980–2008 interval. Weekly collections were made from sediment traps deployed below the thermocline from April to October in the deepest area of the lake (19.5 m). Downward fluxes of TSS (DFTSS), FSS (DFFSS) and VSS (DFVSS) decreased 42, 38, and 41%, respectively, following closure of a soda ash facility in 1986 that discharged ionic waste to the lake. The DFTSS decreased 47% from 2007 to 2008, driven mostly by lower CaCO3 deposition. Sediment accumulation rates derived from dry weight deposition were estimated to decrease from 0.8 cm/yr during 1980–1986 to 0.4 cm/yr during 1987–2007 to 0.2 cm/yr in 2008....
Height and weight of early 20th century Filipino men

Background : Recent anthropometric studies of Filipinos have concentrated on women and children. While present-day studies of Filipino men are few, scattered sources of historical height and weight samples exist and can be studied to estimate a rough baseline for comparison, as well as to study trends in the past. Aim : This paper estimates heights and weights of men in the Philippines about a century ago. Height-by-age profiles and comparisons to contemporary populations in south-east Asia as well as present day Filipinos provide context. Subjects and methods : One sample consisted of 843 prisoners from throughout the islands, who were measured by an American anthropologist in Manila. A previously overlooked published source included measurements of 1016 seamen, police and prison guards, and civil servants in Manila. A contemporary source also measured 100 relatively remote Igorrote in Luzon. Results : Average heights fell in a relatively narrow range of 1.60-1.62 m, except for police who were subject to...
Solving heat exchanger network synthesis problems with Tabu Search

Abstract This paper describes the implementation of a meta-heuristic optimization approach, Tabu Search (TS), for heat exchanger networks (HEN) synthesis and compares this approach to others presented in the literature. TS is a stochastic optimization approach that makes use of adaptive memory in the form of Tabu lists. Both recency- and frequency-based Tabu lists are used to provide short- and long-term knowledge of search history. TS is shown to locate the global optima with a high probability and low computation times, demonstrating the algorithm’s potential for solving a variety of other mixed integer nonlinear programming (MINLP) problems.
Expansion of CD4+CD28null T-lymphocytes in diabetic patients: exploring new pathogenetic mechanisms of increased cardiovascular risk in diabetes mellitus

Aims Diabetes mellitus (DM) is associated with high incidence of first and recurrent cardiovascular events, especially acute coronary syndromes (ACSs); however, the mechanisms involved are still unknown. We sought to investigate the role of CD4+CD28nullT-lymphocytes, a rare long-lived subset of T-lymphocytes with proatherogenic and plaque-destabilizing properties, in the increased cardiovascular risk associated with DM. Methods and results CD4+CD28nullT-cell frequency was analysed by flow-cytometry in 60 DM patients without overt cardiovascular disease (cDM), in 166 ACS patients with or without DM (ACS/DM+, n = 51 and ACS/DM−, n = 115), and in 60 healthy individuals. The incidence of cardiovascular events (death, myocardial infarction, unstable angina) was assessed at 36 months follow-up . CD4+CD28nullT-cell frequency (median, range) was higher in ACS/DM+ (12.7%, 0.1–48) vs. ACS/DM− (3.9%, 0.2–35), cDM (3.1%, 0.3–22.4), and controls (1.5%, 0.1–9.1) ( P < 0.001 for all comparisons). Notably, cDM patients had significantly higher CD4+CD28nullT-cell frequency than controls ( P = 0.001). Glycosylated haemoglobin A1c was the only parameter independently associated with CD4+CD28nullT-cells in cDM. The 36-month event-free survival was significantly lower in cDM patients with CD4+CD28nullT-cells ≥4% (90th percentile of normal distribution) than in those with CD4+CD28nullT-cells <4% ( P = 0.039). Among ACS patients, the 36-month event-free survival was the lowest in those with DM and CD4+CD28nullT-cells ≥4% and highest in those without DM and CD4+CD28nullT-cells <4% ( P < 0.001), being intermediate in those with only one of these features. Conclusions In DM patients, CD4+CD28nullT-cells are expanded and are associated with poor glycaemic control; they also correlate with the occurrence of a first cardiovascular event and with a worse outcome after an ACS.
Localized repressors delineate the neurogenic ectoderm in the early Drosophila embryo

The Dorsal gradient produces sequential patterns of gene expression across the dorsoventral axis of early embryos, thereby establishing the presumptive mesoderm, neuroectoderm, and dorsal ectoderm. Spatially localized repressors such as Snail and Vnd exclude the expression of neurogenic genes in the mesoderm and ventral neuroectoderm, respectively. However, no repressors have been identified that establish the dorsal limits of neurogenic gene expression. To investigate this issue, we have conducted an analysis of the ind gene, which is selectively expressed in lateral regions of the presumptive nerve cord. A novel silencer element was identified within the ind enhancer that is essential for eliminating expression in the dorsal ectoderm. Evidence is presented that the associated repressor can function over long distances to silence neighboring enhancers. The ind enhancer also contains a variety of known activator and repressor elements. We propose a model whereby Dorsal and EGF signaling, together with the localized Schnurri repressor, define a broad domain of ind expression throughout the entire presumptive neuroectoderm. The ventral limits of gene expression are defined by the Snail and Vnd repressors, while the dorsal border is established by the newly defined silencer element.
A Recirculating Equilibrium Procedure for Determining Organic Compound Solubility in Supercritical Fluids. Anthracene in Carbon Dioxide

An instrumental recirculation technique was developed to measure the solubility of organic compounds and thus their potential extractability, in supercritical fluids over the pressure range of 80−500 bar. Anthracene, whose solubility is well defined, was chosen as a model compound to be used in evaluating the recirculation technique. Its solubility in supercritical carbon dioxide was measured at 40, 50, and 60 °C using an off-line spectroscopic technique. The solubility data were found to have good precision and to agree with published results. Anthracene solubility increased with pressure but was more enhanced by higher temperature. An upper crossover pressure of the isotherms due to retrograde vaporization that agreed with theory was found at 142.2 bar.
DATING OF TERTIARY VOLCANIC ROCKS BY THE POTASSIUM-ARGON METHOD*

The possibility of using volcanic glasses for potassium-argon dating is investigated. The following properties must be available in the mineral: it should be relatively widespread in ratural settings; it should be completely outgassed of argon at the time of the geological event it is to mark; it should undergo little loss of argon by diffusion; and it should contain a reasonable amount of potassium. From the mass spectrometer measurements made in this preliminary investigation it is concluded that volcanic glasses have a good possibility of being a useful mineral for K--Ar dating, provided that samples are taken only from fairly large specimens. (N.W.R.)
The Inclined Rhombic Antenna

In this paper, the use of an inclined rhombic antenna as a means for reducing the effect offading is discussed. Equations are given for determining the angle at which a rhombic antenna should be inclined to obtain a desired response pattern at various elevation angles in the vertical plane containing the major axis.
The Ashwell receptor mitigates the lethal coagulopathy of sepsis

The Ashwell receptor, the major lectin of hepatocytes, rapidly clears from blood circulation glycoproteins bearing glycan ligands that include galactose and N-acetylgalactosamine. This asialoglycoprotein receptor activity remains a key factor in the development and administration of glycoprotein pharmaceuticals, yet a biological purpose of the Ashwell receptor has remained elusive. We have identified endogenous ligands of the Ashwell receptor as glycoproteins and regulatory components in blood coagulation and thrombosis that include von Willebrand factor (vWF) and platelets. The Ashwell receptor normally modulates vWF homeostasis and is responsible for thrombocytopenia during systemic Streptococcus pneumoniae infection by eliminating platelets desialylated by the bacterium's neuraminidase. Hemostatic adaptation by the Ashwell receptor moderates the onset and severity of disseminated intravascular coagulation during sepsis and improves the probability of host survival.
Flexible Scheduling of Multicast Sessions with Different Granularities for Large Data Distribution over WDM Networks

Many networking applications require distribution of data from a central point to multiple destinations; this distribution can be efficiently achieved by the means of multicasting. Traditionally, multicasting has been considered for on-demand applications such as HDTV, Video-on-Demand (VoD), IPTV, which usually require to start data transmission immediately. However, in the case of emerging e-Science and high-performance applications (which frequently need to replicate large datasets to multiple locations), the data distribution does not necessarily need to take place instantaneously; instead, the multicast session can be accommodated considering a flexible start time for the large data transfer. We study the efficient provisioning of Multicast Data-Distribution Requests (MDDRs) with flexible scheduling over WDM networks. We consider the practical case of multicast sessions that may require less than the entire capacity of a wavelength; hence the multicast sessions need to be "trafficgroomed". Our first multicast provisioning approach (named Rand) generates randomized alternate multicast trees on which we try to provision the multicast session, and then attempts to assign wavelengths and schedule the session's start time. In our second approach (named AllSlots), for each available start time S, we dynamically generate trees depending on the network state at time S. In our next approach (named Break), for the cases when provisioning an entire multicast tree fails, we enable the possibility of "breaking" the tree into subtrees (with independent start times) serving subsets of destinations. Moreover, we study the impact of partitioning the datasets into pieces on our multicast provisioning approaches, and also compare our multicast algorithms with an unicast approach.
Feature Matching and Adaptive Prediction Models in an Object Tracking DDDAS

We consider the optical remote sensing tracking problem for vehicles in a complex environment using an adaptive sensor that can take spectral data at a small number of locations. The Dynamic Data-Driven Applications Systems (DDDAS) paradigm is well-suited for dynamically controlling such an adaptive sensor by using the prediction of object movement and its interaction with the environment to guide the location of spectral measurements. The spectral measurements are used for target identification through feature matching. We consider several adaptive sampling strategies for how to assign locations for spectral measurements in order to distinguish between multiple targets. In addition to guiding the measurement process, the tracking system pulls in additional data from OpenStreetMap to identify road networks and intersections. When a vehicle enters a detected intersection, it triggers the use of a multiple model prediction system to sample all possible turning options. The result of this added information is more accurate predictions and analysis from data assimilation using a Gaussian Sum filter (GSF).
Surfactant protein D regulates NF-kappa B and matrix metalloproteinase production in alveolar macrophages via oxidant-sensitive pathways.

Targeted ablation of the surfactant protein D (SP-D) gene caused progressive pulmonary emphysema associated with pulmonary infiltration by foamy alveolar macrophages (AMs), increased hydrogen peroxide production, and matrix metalloproteinase (MMP)-2, -9, and -12 expression. In the present study, the mechanisms by which SP-D influences macrophage MMP activity were assessed in AMs from SP-D −/− mice. Tissue lipid peroxides and reactive carbonyls were increased in lungs of SP-D −/− mice, indicating oxidative stress. Immunohistochemical staining of AMs from SP-D −/− mice demonstrated that NF-κB was highly expressed and translocated to the nucleus. Increased NF-κB binding was detected by EMSA in nuclear extracts of AMs isolated from SP-D −/− mice. Antioxidants N -acetylcysteine and pyrrolidine dithiocarbamate inhibited MMP production by AMs from SP-D −/− mice. To assess whether increased oxidant production influenced NF-κB activation and production of MMP-2 and -9, AMs from SP-D −/− mice were treated with the NADPH oxidase inhibitors diphenylene iodonium chloride and apocynin. Inhibition of NADPH oxidase suppressed NF-κB binding by nuclear extracts and decreased production of MMP-2 and 9 in AMs from SP-D −/− mice. SN-50, a synthetic NF-κB-inhibitory peptide, decreased MMP production by AMs from SP-D −/− mice. Oxidant production and reactive oxygen species were increased in lungs of SP-D −/− mice, in turn activating NF-κB and MMP expression. SP-D plays an unexpected inhibitory role in the regulation of NF-κB in AMs.
Insider Trading, Earnings Quality, and Accrual Mispricing

The paper provides evidence that the signal contained in insiders' trading behavior is useful in making refined assessments of earnings quality, and informative about the valuation implications of accruals. We find that income-increasing accruals and unexpected accruals have lower (higher) persistence when managers engage in abnormal selling (buying) suggesting that insider trading information is useful in assessing the quality of the non-cash components of earnings. We show that the accrual mispricing phenomenon observed in previous work is largely due to the mispricing of positive accruals. We find that investors price all positive accruals as if they were informative and that a subset of positive accruals is correctly priced. That is, (1) investors correctly price positive accruals that are likely to be informative because concurrently insiders engage in abnormal buying, and (2) investors price all positive accruals the same independently of insider trading. We find that the extent of the mispricing is greater when positive accruals occur concurrently with abnormal selling relative to cases where there is no trading. The extent of the mispricing and the magnitude of the one-year ahead returns (14.7 to 22 percent) to a trading strategy based on positive accruals and abnormal selling suggests that these accruals arise from opportunistic earnings management that is successful in misleading investors. By contrast, the smaller positive accrual mispricing when there is no insider trading is more likely related to either the complexity of the firms' accrual generating process (Thomas and Zhang (2001) or to earnings fixation (Sloan 1996). Our evidence thus suggests that opportunistic earnings management is a partial explanation for the accrual mispricing phenomenon.
A Model of Evolutionary Dynamics with Quasiperiodic Forcing

Evolutionary dynamics combines game theory and nonlinear dynamics to model competition in biological and social situations. The replicator equation is a standard paradigm in evolutionary dynamics. The growth rate of each strategy is its excess fitness: the deviation of its fitness from the average. The game-theoretic aspect of the model lies in the choice of fitness function, which is determined by a payoff matrix.Previous work by Ruelas and Rand investigated the Rock-Paper-Scissors replicator dynamics problem with periodic forcing of the payoff coefficients. This work extends the previous to consider the case of quasiperiodic forcing. This model may find applications in biological or social systems where competition is affected by cyclical processes on different scales, such as days/years or weeks/years.We study the quasiperiodically forced Rock-Paper-Scissors problem using numerical simulation, and Floquet theory and harmonic balance. We investigate the linear stability of the interior equilibrium point; we find that the region of stability in frequency space has fractal boundary.
Pigmented Potato Consumption Alters Oxidative Stress and Inflammatory Damage in Men

Pigmented potatoes contain high concentrations of antioxidants, including phenolic acids, anthocyanins, and carotenoids. These bioactive compounds have been implicated in the inhibition or prevention of cellular oxidative damage and chronic disease susceptibility. We assessed the effects of pigmented potato consumption on oxidative stress and inflammation biomarkers in adult males. Free-living healthy men (18-40 y; n = 12/group) consumed 150 g of cooked white- (WP), yellow- (YP), or purple-flesh potatoes (PP) once per day for 6 wk in a randomized study. Blood was collected at baseline and wk 6 to analyze total antioxidant capacity (TAC), DNA damage as assessed by plasma 8-hydroxydeoxyguanosine (8-OHdG), protein oxidation, lipid peroxidation, C-reactive protein (CRP), inflammatory cytokines, lymphoproliferation, NK cytotoxicity, and phenotypes. Potatoes were analyzed for TAC, phenolic acids, anthocyanins, and carotenoids. Compared with the WP group, the YP group had higher concentrations of phenolic acids (P < 0.002) and carotenoids (P < 0.001), whereas the PP group had higher concentrations of phenolic acids (P < 0.002) and anthocyanins (P < 0.001). Men who consumed YP and PP tended to have lower (P < 0.08) plasma IL-6 compared with those consuming WP. The PP group tended to have a lower plasma CRP concentration than the WP group (P = 0.07). The 8-OHdG concentration was lower in men who consumed either YP or PP compared with WP. Pigmented potato consumption reduced inflammation and DNA damage in healthy adult males. This offers consumers an improved nutritional choice in potato consumption.
Certain Aspects of Medical Research and Its Support

The origins of the National Institutes of Health (NIH) are linked with European science. Few Americans had participated in the advances in bacteriology led by Koch and Pasteur when a laboratory from which the NIH eventually developed was established in New York in 1887, but its first director patterned this laboratory after ones already established in Germany, France, and England. The era of modern biomedical research in the United States began during World War II with the cooperation of government and nongovernment (mostly academic) research laboratories. Today, the philosophical foundation underlying all research-supporting programs of the NIH is that a close connection exists between improved medical care and research and that any expansion of medical facilities must be accompanied by an expansion of medical training and research. In addition, government grants should not interfere with the freedom and integrity of academic institutions and should allow scientists complete independence in determining the nature, scope, and methodology of their investigations. Discoveries in genetics in the 1950's and 1960's heralded an era of science in which it was necessary to address major questions with immediate relevance to human health. Impelled by pressure from the public, the scientific community, and the Congress, the NIH participates in formulating safety guidelines regarding potential applications of biotechnology. The annual increase in funds appropriated by Congress to the NIH attests to a high level of public commitment to the support of biomedical research and underlines the degree of accountability to which the NIH is subject.
Modeling queueing and channel access delay in unsaturated IEEE 802.11 random access MAC based wireless networks

In this paper, we present an analytic model for evaluating the queueing delays and channel access times at nodes in wireless networks using the IEEE 802.11 Distributed Coordination Function (DCF) as the MAC protocol. The model can account for arbitrary arrival patterns, packet size distributions and number of nodes. Our model gives closed form expressions for obtaining the delay and queue length characteristics and models each node as a discrete time G/G/1fs queue. The service time distribution for the queues is derived by accounting for a number of factors including the channel access delay due to the shared medium, impact of packet collisions, the resulting backoffs as well as the packet size distribution. The model is also extended for ongoing proposals under consideration for 802.11e wherein a number of packets may be transmitted in a burst once the channel is accessed. Our analytical results are verified through extensive simulations. The results of our model can also be used for providing probabilistic quality of service guarantees and determining the number of nodes that can be accommodated while satisfying a given delay constraint.
SOLITARY DRINKING, SOCIAL ISOLATION, AND ESCAPE DRINKING MOTIVES AS PREDICTORS OF HIGH QUANTITY DRINKING, AMONG ANGLO, AFRICAN AMERICAN AND MEXICAN AMERICAN MALES

This paper addresses the phenomenon of 'solitary drinking', considering whether Anglo, African American and Mexican American male regular drinkers differ in the propensity to drink in solitary contexts and whether such differences may help to explain observed ethnic variation in patterns of heavy drinking. Further, the paper considers whether apparent relationships between solitary drinking and drinking patterns are explained by individual personality characteristics such as social isolation and/ or by endorsement of 'escape drinking' motives. Data were analysed from a random community sample of 481 adult male regular drinkers in San Antonio, Texas, USA. Contingency table and logistic regression analyses indicated that initially observed ethnic differences in high quantity and high maximum drinking were largely eliminated by controls for education, escape motives and solitary drinking. Ethnic variation in the role of solitary drinking was suggested as well, with solitary drinking more strongly related to high quantity consumption, in particular, among African Americans than among Mexican Americans. The nature of the observed interactions suggests that fundamental differences between Anglos and African Americans in the roles of solitary drinking and escape drinking motives may underlie seemingly similar frequent, lower quantity drinking patterns in these groups that appear more frequently than among Mexican American males.
Robot audition and beat identification in noisy environments

In pursuit of our long-term goal of developing an interactive humanoid musician, we are developing robust methods to determine musical beat locations from live acoustic sources. A variety of beat tracking systems have been previously developed, but for the most part they are optimized for direct audio input (no acoustic channel and no noise). The presence of an acoustic channel and noise typically degrades performance substantially. A robot's motors, in particular, create nonstationary noise that can be difficult for a beat detection system to accommodate, Using an algorithm previously developed by the authors, we explore techniques for reducing the effects of the acoustic channel and noise on the system, enabling a humanoid to robustly follow music under realistic conditions.
Primary and Secondary Malposition of Silicone Central Venous Catheters

We reviewed our experience with the percutaneous insertion of 459 silicone central venous catheters from 1979 to 1984. Special attention was given to the complication of malposition of these catheters. From 1981-1984, 116 consecutive percutaneous silicone central venous catheters (CVC) were inserted using the peel away sheath introducer. There were no primary catheter malpositions using this technique; however, secondary malposition occurred with 6% of the catheters. In addition to the use of this technique, patient response to movement of the guidewire during the catheterization procedure is described. The details of catheter insertion technique which permit operative assessment of the correctness of catheter location are presented. Symptoms and signs of secondary catheter malposition, as well as management required for this problem, are discussed.
TIME-BASED BEHAVIORS AT AN INTERACTIVE SCIENCE MUSEUM : EXPLORING THE DIFFERENCES BETWEEN WEEKDAY/WEEKEND AND FAMILY/NONFAMILY VISITORS

The purpose of this study was to determine if time-based learning-associated visitor behaviors at interactive science museums differ across weekend/weekday groups and family/nonfamily groups. Forty-seven visitors were tracked through two interactive, thematic exhibitions at the Reuben Fleet Science Center. Statistical analysis of five separate dependent measures showed that: (a) regardless of the day of the visit, families spent more time than nonfamilies in individual exhibitions and in the science museum as a whole; (b) there was a separation of weekday visitors into two distinct groups: family visitors who spent, on average, almost 2 minutes per exhibit, and nonfamily visitors who spent, on average, less than 1 minute per exhibit; and (c) weekend family and nonfamily visitors did not differ in their average time spent per exhibit. These results are explained by a difference in visitor agendas and the crowded nature of weekend visits. © 1997 John Wiley & Sons, Inc. Sci Ed 81:689 - 701, 1997.
Pacific-North America plate motions - New results from very long baseline interferometry

The state of Pacific-North America plate interaction is updated using newest VLBI measurements and newly developed rigid plate tectonic models. Particular attention is given to examining the extent of relative motion between the Pacific plate and the North America plate as measured from their stable interiors, the evidence of Pacific plate deformation off the central California coast, and the distribution of path integrated deformaton east of the San Andreas fault. The information obtained on these questions is discussed in the framework of implications for lithospheric rheology and earthquake hazard.
A note on the assumption of quasiequilibrium in semiconductor junction devices

It is shown that the quasi-equilibrium theory for p-n junctions, as originally proposed by Shockley (1949), does not apply under conditions involving an application of comparatively low external voltages. A numerical example indicates that the quasi-equilibrium assumption must be discarded as soon as the voltage is increased beyond a certain critical value, although the system may still be in a low-level injection regime. It is currently not known which set of simplifying assumptions may replace the quasi-equilibrium assumptions. Possible analytic simplification relations applicable to moderate or high injection levels can, perhaps, be based on an approach considered by Mari (1968) and Choo (1971, 1972).
Optimal Feedback Control of a Bioreactor with a Remote Sensor

Sensors used to monitor bioreactor conditions directly often perform poorly in the face of adverse nonphysiological conditions. One way to circumvent this is to use a remote sensor block. However such a configuration usually causes a significant time lag between measurements and the actual state values. In this work the problem of implementing feedback control strategies for such systems described by nonlinear equations is addressed. The problem is posed as an optimal control problem with a linear quadratic performance index. The linear control law so obtained is used to implement feedback. A global linearization technique as well as an expansion using Taylor series is used to effectively linearize the nonlinear system and the feedback is subsequently implemented.
Multiscale classification using complex wavelets and hidden Markov tree models

Multiresolution signal and image models such as the hidden Markov tree (HMT) aim to capture the statistical structures of smooth and singular (textured and edgy) regions. Unfortunately, models based on the orthogonal wavelet transform suffer from shift-variance, making them less accurate and realistic. We extend the HMT modeling framework to the complex wavelet transform, which features near shift-invariance and improved angular resolution compared to the standard wavelet transform. The model is computationally efficient (featuring linear-time computation and processing algorithms) and applicable to general Bayesian inference problems as a prior density for the data. We develop a simple multiscale maximum likelihood classification scheme based on the complex wavelet HMT that outperforms methods based on real-valued wavelet HMTs. The resulting classifier can be used as a front end in a more sophisticated multiscale segmentation algorithm.
Adaptive output feedback control with reduced sensitivity to sensor noise

We address adaptive output feedback control of uncertain nonlinear systems with noisy output measurements, in which both the dynamics and the dimension of the regulated systems may be unknown, and only the relative degree of the regulated output is assumed to be known. Given a smooth reference trajectory, the problem is to design a controller that forces the system measurement to track it with bounded errors. A recently developed method proposes the use of a linear error observer that estimates the tracking error and its derivatives. Since the observer is full order, it also estimates the states of the controller, even though these states are exactly known. It has been observed experimentally that the resulting adaptive control architecture is very sensitive to sensor noise. In this paper we provide a specific reduced order observer that significantly reduces sensitivity to sensor noise in adaptive control design. Experimental results on a three degrees of freedom laboratory model helicopter are used to illustrate the effectiveness of the reduced order observer design.
Plk1 Regulates Activation of the Anaphase Promoting Complex by Phosphorylating and Triggering SCFβTrCP-dependent Destruction of the APC Inhibitor Emi1

Progression through mitosis requires activation of cyclin B/Cdk1 and its downstream targets, including Polo-like kinase and the anaphase-promoting complex (APC), the ubiquitin ligase directing degr...
Design sketches and sketch design tools

In early stages of design architects often use sketching and diagramming to perform formal and functional reasoning. Design sketches are an external representation aid for visualization and evaluation of the spatial arrangements of artifacts. Symbols and configurations are used in design sketches to define context and object arrangements. This paper argues the need to study design drawing, reports the findings from empirical studies of design drawings, and describes the software systems implemented to support intention inference and automated activation of knowledge-based design tools to support design.
The effect of egg fatty acid concentrations on embryo viability in wild and domesticated walleye ( Stizostedion vitreum )

Eggs from three distinct populations of walleye Stizostedion vitreum, one domesticated (London State Fish Hatchery) and two wild (Lake Erie and Salt Fork Reservoir), were compared in terms of total lipid content and fatty acid profiles (phospholipids and neutral lipids). The concentrations of total lipids in eggs from domesticated broodstock were significantly lower (8.6 ± 1.0 % of wet weight) than those of both wild populations (13.3 ± 0.9 % and 10.9 ± 0.6 % of wet weight for Lake Erie and Salt Fork Reservoir, respectively). The profiles of fatty acids in egg lipids differed significantly among the three investigated populations. Domesticated females fed a formulated diet produced eggs containing significantly higher levels of linoleic acid (18:2n-6), characteristic of plant lipids. However, arachidonic acid (20:4n-6), was at significantly higher levels in eggs of wild walleye stocks. Although eicosapentaenoic acid (20:5n-3) was detected at significantly higher levels in eggs from Lake Erie walleye, docosahexaenoic acid (22:6n-3), the most abundant in polar lipids, was found at similar levels in eggs of all three populations. Survival of walleye embryos was correlated with the concentrations of polyunsaturated long chain fatty acids. Our data suggest that deficiency in n-3 fatty acids might be associated with impaired development of walleye, and thus poor larval and juvenile viability.
AGTR1 overexpression defines a subset of breast cancer and confers sensitivity to losartan, an AGTR1 antagonist

Breast cancer patients have benefited from the use of targeted therapies directed at specific molecular alterations. To identify additional opportunities for targeted therapy, we searched for genes with marked overexpression in subsets of tumors across a panel of breast cancer profiling studies comprising 3,200 microarray experiments. In addition to prioritizing ERBB2, we found AGTR1, the angiotensin II receptor type I, to be markedly overexpressed in 10–20% of breast cancer cases across multiple independent patient cohorts. Validation experiments confirmed that AGTR1 is highly overexpressed, in several cases more than 100-fold. AGTR1 overexpression was restricted to estrogen receptor-positive tumors and was mutually exclusive with ERBB2 overexpression across all samples. Ectopic overexpression of AGTR1 in primary mammary epithelial cells, combined with angiotensin II stimulation, led to a highly invasive phenotype that was attenuated by the AGTR1 antagonist losartan. Similarly, losartan reduced tumor growth by 30% in AGTR1-positive breast cancer xenografts. Taken together, these observations indicate that marked AGTR1 overexpression defines a subpopulation of ER-positive, ERBB2-negative breast cancer that may benefit from targeted therapy with AGTR1 antagonists, such as losartan.
Quantitative DNA slot blot analysis: inhibition of DNA binding to membranes by magnesium ions

Titers of wild-type and recombinant adeno-associated viruses are routinely determined by DNA slot blot analysis. The binding of viral DNA to nylon membranes was found to be inhibited by magnesium ions, which are critical components of the DNase I digestion carried out prior to slot blot analysis. Mg 2+ ions also interfered with the adsorption of plasmid DNA to nylon and nitrocellulose membranes. These observations yield practical insights into the poorly understood mechanisms by which DNA molecules are retained on solid supports. The observation made by Nygaard and Hall (1), that denatured DNA and complexes between DNA and RNA can be adsorbed to nitrocellulose, paved the way for development of modern molecular biological techniques that require immobilization of nucleic acids on solid supports. These techniques include Southern and Northern transfers, dot-blotting, colony hybridization and plaque-lifts. The underlying mechanism of adsorption of nucleic acids to nitrocellulose membranes remains unclear, but has been assumed to be non-covalent (2). Studies of the interactions between nucleic acids and modified celluloses, such as nitrocellulose, have revealed that molecular weight, finite macromolecular conformation, ionic forces and weaker forces of attraction all play a role (3,4). DNA is retained on nitrocellulose only in buffers of high ionic strength. This may be because increasing salt concentration correlates with decreasing electrostatic repulsion between the phosphate groups of the DNA backbone, yielding more aggregated DNA molecules that are more easily retained on the filter (5). Nylon membranes have a greater mechanical strength, a higher binding capacity for nucleic acids, and a stronger retention of bound nucleic acids than nitrocellulose membranes. They are able to bind both native and denatured nucleic acids in buffers of low ionic strength (6). Positively charged nylon membranes provide an ionic interaction between the negatively charged phosphate groups of the nucleic acid and the positively charged groups of the membrane. DNA slot blot analysis is used routinely to quantitate the concentrations of adeno-associated virus 2 (AAV) particles in virus stocks (7). Since virions are generated from transfected plasmid DNA, virus stocks are treated with pancreatic deoxyribonuclease (DNase I) prior to slot blot analysis to degrade plasmid DNA as well as unencapsidated virion DNA that would lead to erroneously high estimates of viral titers. We report here that binding of viral DNA released from disrupted virions to a nylon membrane is
Computer Aquisition for the Small Contractor

This paper provides a brief background of computer applications in construction and outlines the procurement process, for small to medium firms including decision criteria, request for proposal, vendor solicitation, guarantees and proposal evaluations. Some pitfalls to avoid are also noted.
Parietal and prefrontal: categorical differences?

A working memory representation goes missing in monkey parietal cortex during categorization learning, but is still found in the prefrontal cortex.