cssi/SciSciGPT-SciSciNet huggingface dataset:
Modulation loss analysis for amplitude modulated FSK signal

The satellite control uplink waveform known as SGLS (Space-to-Ground Link System) for commanding satellites currently used by the U.S. Department of Defense (DOD), uses ternary frequency shift keying (FSK), which is amplitude modulated using a triangular waveform. Although this has been in use for a half-century, we are unaware of any reference that rigorously describes its fundamental performance characteristics — specifically, its ideal bit error rate as a function of uplink power. This requires knowing the ideal baseband bit error rate as well as the allocation of total power into the command channel. A frequent alternative for the allocation of power in the command channel is to use the allocation given by the lowest-order terms of an analytic Bessel function expansion, in which the command channel is modeled as a single phase-modulated subcarrier. This alternative is also compromised by the neglect of amplitude modulation (AM). A rigorous characterization of SGLS is necessary in order to quantify the relative performance of new uplink waveforms that are being contemplated by DOD. In this paper, rigorous equations for use in the evaluation of the effect of AM on SGLS uplink modulation losses are presented. It is shown in this paper that the triangular wave amplitude modulation is well approximated as a single sinusoid normalized in terms of power. Analytical expressions are provided for the modulation losses that include AM effects supported by simulation results. For the typical SGLS uplink with a value of modulation envelope factor equal to 0.5, the effect of AM is to reduce the power in each spectral component of the uplink by less than 10%. This amount corresponds to less than a dB in most cases. It is shown in this paper that for the purpose of link margin calculations, it is adequate to conservatively allow an additional 1 dB for the modulation losses and ignore the AM in the modulation loss equations.
An efficient multipath structure for concurrent data transport in wireless mesh networks

Multipath routing is employed extensively in wireless mesh networks for fault tolerance, throughput enhancement, and load balancing purposes. Most existing multipath routing methods tend to establish link-disjoint or node-disjoint paths with minimal path costs. As paths created by these methods are typically close to each other, they may cause serious inter-path interference when serving for concurrent data transmissions. In this paper, we first introduce an AODV-based decoupled multipath routing protocol named AODV-DM. AODV-DM builds an insulating region around each established path to prevent new paths from being formed in the neighborhood of the established path. Multiple paths formed by this means are ''isolated'' from each other; thereby they are very suitable to serve for concurrent data transmissions. We also investigate the transport-layer route-coupling problem, and conclude that a path-aware SCTP scheme is a very good match to our AODV-DM protocol. The path-aware SCTP scheme enables the transport layer to make the most of the capacity provided by decoupled multipath. We simulate the AODV-DM protocol and integrate it with the path-aware SCTP protocol. The simulation results demonstrate that AODV-DM, combined with the path-aware SCTP, significantly boosts end-to-end throughput of multihop data transmissions. This decoupled multipath structure is especially beneficial to concurrent transmissions of time-constraint data in wireless mesh networks.
A Peptide Export-Import Control Circuit Modulating Bacterial Development Regulates Protein Phosphatases of the Phosphorelay

The phosphorelay signal transduction system activates developmental transcription in sporulation of Bacillus subtilis by phosphorylation of aspartyl residues of the Spo0F and Spo0A response regulators. The phosphorylation level of these response regulators is determined by the opposing activities of protein kinases and protein aspartate phosphatases that interpret positive and negative signals for development in a signal integration circuit. The RapA protein aspartate phosphatase of the phosphorelay is regulated by a peptide that directly inhibits its activity. This peptide is proteolytically processed from an inactive pre-inhibitor protein encoded in the phrA gene. The pre-inhibitor is cleaved by the protein export apparatus to a putative pro-inhibitor that is further processed to the active inhibitor peptide and internalized by the oligopeptide permease. This export-import circuit is postulated to be a mechanism for timing phosphatase activity where the processing enzymes regulate the rate of formation of the active inhibitor. The processing events may, in turn, be controlled by a regulatory hierarchy. Chromosome sequencing has revealed several other phosphatase-prepeptide gene pairs in B. subtilis, suggesting that the use of this mechanism may be widespread in signal transduction.
Improvements in WRF simulation skills of southeastern United States summer rainfall: physical parameterization and horizontal resolution

Realistic regional climate simulations are important in understanding the mechanisms of summer rainfall in the southeastern United States (SE US) and in making seasonal predictions. In this study, skills of SE US summer rainfall simulation at a 15-km resolution are evaluated using the weather research and forecasting (WRF) model driven by climate forecast system reanalysis data. Influences of parameterization schemes and model resolution on the rainfall are investigated. It is shown that the WRF simulations for SE US summer rainfall are most sensitive to cumulus schemes, moderately sensitive to planetary boundary layer schemes, and less sensitive to microphysics schemes. Among five WRF cumulus schemes analyzed in this study, the Zhang–McFarlane scheme outperforms the other four. Further analysis suggests that the superior performance of the Zhang–McFarlane scheme is attributable primarily to its capability of representing rainfall-triggering processes over the SE US, especially the positive relationship between convective available potential energy and rainfall. In addition, simulated rainfall using the Zhang–McFarlane scheme at the 15-km resolution is compared with that at a 3-km convection-permitting resolution without cumulus scheme to test whether the increased horizontal resolution can further improve the SE US rainfall simulation. Results indicate that the simulations at the 3-km resolution do not show obvious advantages over those at the 15-km resolution with the Zhang–McFarlane scheme. In conclusion, our study suggests that in order to obtain a satisfactory simulation of SE US summer rainfall, choosing a cumulus scheme that can realistically represent the convective rainfall triggering mechanism may be more effective than solely increasing model resolution.
Implementation and evaluation of guidelines for use of enoxaparin as deep vein thrombosis prophylaxis after major trauma.

Although enoxaparin is more efficacious than many other deep vein thrombosis (DVT) prevention strategies after trauma, its routine use in trauma patients at low risk for venous thrombosis is unlikely to be cost-effective and may be deleterious if risk factors for bleeding are present. By way of consensus of opinion of trauma surgeons and pharmacists, enoxaparin DVT prophylaxis guidelines were developed, implemented, and evaluated. Fifty patients with major orthopedic or spinal trauma were followed throughout hospitalization. Enoxaparin use and frequency of DVT, pulmonary embolism (PE), thrombocytopenia, and enoxaparin-related major bleeding (overt bleeding associated with a hemoglobin decrease ≥ 2 g/dl, need for ≥ 2 units of packed red blood cells, or need for surgery) were recorded. All pharmacist interventions pertaining to enoxaparin prophylaxis were collected. Average patient age was 45.6 ± 19.5 years, average Injury Severity Score was 19.0 ± 11.2, and average length of hospitalization was 14.3 ± 10.0 days. Most injuries were related to motor vehicles (52%) and falls (30%). Sites of injury were femur or tibia (52%), pelvis or acetabulum (32%), hip (20%), and spinal cord (12%). Two-thirds (72%) of patients received enoxaparin during part of their hospital stay (on average, for 53% of the duration of hospitalization). Sequential compression devices and vena caval filters were used in 86% and 10% of patients, respectively. Duplex-proven DVT occurred in two patients, and angiography-proven PE developed in one patient. Enoxaparin-related major bleeding and thrombocytopenia occurred in three and one patient(s), respectively. Pharmacists recommended enoxaparin initiation in nine (18%) patients and discontinuation of the agent in seven (14%) patients (one for bleeding; six for lack of indication). Most recommendations (78%) were accepted. Data from the 50 patients in this study showed fewer thrombotic complications but more bleeding than the frequencies found in controlled studies. It is unclear whether the large number of days that patients did not receive enoxaparin was due to fears of enoxaparin-related bleeding or other factors.
Decay of Os 182 and Os 183 . II. Coincidences, Conversion Coefficients, and Decay Schemes

The 382-kev transition in ${\mathrm{Re}}^{183}$ was shown to have a conversion coefficient of (1.09\ifmmode\pm\else\textpm\fi{}0.14)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}2}$ which established the transition as $E1$. The half-life of the state from which this arises was found to be (7.7\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec from delayed coincidence measurements, indicating a hindrance factor of 3\ifmmode\times\else\texttimes\fi{}${10}^{6}$ relative to the single particle value. Other transition multipolarities were assigned from their conversion coefficients, $L$ subshell and $\frac{K}{L}$ ratios as obtained from the preceding paper. Amongst these the 170.72-kev isomeric transition in ${\mathrm{Os}}^{183}$ was identified and shown to be $M4$ with a hindrance factor of 12. Decay schemes for ${\mathrm{Os}}^{183}$ and ${\mathrm{Os}}^{183m}$ are established and good agreement is obtained between the proposed spins and parties and those suggested by the scheme of energy levels in a spheroidal potential as calculated by Nilsson.
Shear‐Band Analysis in Idealized Granular Material

Two‐dimensional particles experience shear bands as real granular materials; they form a convenient vehicle to investigate shear bands within granular soils. Numerical simulations on these idealized materials are used to assess the assumptions and limitations of the shear‐band analyses that are based on linear stability theory and micropolar continua. These shear‐band analyses are found to be applicable in the postbifurcation range, and they describe the thickness of shear bands and the displacements and rotations of the particles within the shear bands of idealized granular materials. The influence of particle rotation within shear bands validates the use of micropolar models. The thickness of shear bands is strongly influenced by the model parameters controlling the micropolar effects. The constitutive models based on the deformation and flow theories of plasticity predict similarly the emergence and inclination of shear bands, but give different shear‐band thicknesses.
Lessons learned in remediation and restoration in the Oklahoma prairie: A review

Abstract For almost a decade the Tallgrass Prairie Preserve in Oklahoma has been used as a field laboratory for the investigation of aspects of the remediation and restoration of oil and brine spills. Objectives of this work have included: (1) simplification of the remediation process and lowering the cost of remediation; (2) the development of methods to accelerate or jump-start the restoration process; and (3) determining appropriate metrics for assessing the status of soil ecosystem recovery. This research has resulted in a number of lessons learned that will be presented here which can be exported to other exploration and production sites, especially sites located in sensitive ecosystems. Key observations have included the role of a fertilizer amendment in linking the remediation and restoration process at an oil-impacted site, the use of nematodes as ecological indicators in the restoration of oil- and brine-impacted sites, and the development of a two-stage process for remediation of brine impacted sites that does not include significant use of gypsum.
Association between 49 infant gene polymorphisms and preterm delivery

The occurrence of preterm delivery has been increasing in the U.S. Previous studies have identified risk factors for preterm delivery that may have genetic influences. We conducted a case-control study comparing the frequencies of 49 genetic polymorphisms among 62 preterm infants and 553 term infants. The polymorphisms that we examined were involved in xenobiotic-metabolism, blood pressure, coagulation, the inflammatory response, cell-cell interaction, or folate-homocysteine metabolism. Univariate analyses on the individual polymorphisms revealed a statistically significant effect for the variant genotypes compared to the wildtype genotypes in SERPINE1 11053G > T (OR = 0.4, 95% CI = 0.2-0.8). This finding suggests the coagulation/thrombophilic pathway may influence the development of preterm delivery.
Neonatal diethylstilbestrol exposure induces persistent elevation of c-fos expression and hypomethylation in its exon-4 in mouse uterus

Perinatal exposure to diethylstilbestrol (DES) induces reproductive tract cancers later in life in both humans and animals. Because there is no clear evidence that perinatal DES exposure induces gene mutation, we proposed that perinatal DES exposure causes epigenetic methylation changes that result in persistent alterations in gene expression, leading to tumorigenesis. The proto-oncogene c-fos is one of the immediately induced genes in uterine epithelium after estrogen simulation and a key player in uterine carcinogenesis. Here, we investigated c-fos expression in mice neonatally exposed to DES (2 microg/pup/day on postnatal days 1-5). The mRNA levels of c-fos in uteri of neonatal DES-treated mice were persistently 1.4-1.9-fold higher than that in the control mice from day 5 to day 60. Overall, the uterine c-fos expression level in the neonatal DES-exposed group was significantly higher than that in the control group. After examination of the methylation status of the c-fos gene, we found that the CpGs in promoter and intron-1 regions were completely unmethylated. In exon-4, from day 17 to day 60, the percentage of unmethylated CpGs was higher in neonatal DES-exposed mice uteri than that in control (42%, 51%, 47%, and 42% in DES-exposed mice vs 33%, 34%, 33%, and 21% in control mice at day 17, 21, 30, and 60, respectively). These results suggest that perinatal DES exposure may permanently alter gene expression and methylation, and the methylation modification may occur in either the promoter regions or other regulatory sites in the gene.
Application of polling models to computer networks

In many computer-communication protocols, the transmission rights are circulated among the users in cyclic order for the sake of fairness. The performance of such protocols has been analyzed in terms, of multiple-queue cyclic-service models, or polling models. This paper reviews applications of the analytical results for polling models to the following communication networks: the half-duplex transmission, polling data link control, MSAP (BRAM), Newhall loop, and explicit and implicit token passing protocols. Substitution of the network parameters into the parameters of polling models is illustrated, and many numerical examples of network performance are provided. Protocol features that are difficult to incorporate into currently analyzable models are also discussed for potential future research.
OH absorption in the low loss window of ZBLAN(P) glass fibre

Abstract Spectral analysis of the minimum loss region of ZBLAN(P) fibre has yielded a refined loss spectrum for OH, with a contribution at 2.55 μm of 80 dB/km/ppm. Also reported is the best loss of 0.45 ± 0.15 dB/km at 2.35 μm, over 60 m of fibre, which the authors believe is the lowest yet reported.
Effect of Occupational Exposures on Decline of Lung Function in Early Chronic Obstructive Pulmonary Disease

Rationale: Several occupational exposures adversely affect lung function.Objectives: This study reports the influence of continued occupational dust and fume exposures on the rate of decline of lung function in participants with early chronic obstructive pulmonary disease (COPD) studied in a population-based study.Methods: Subjects consisted of 5,724 participants in the Lung Health Study, a multicenter study of smoking cessation and anticholinergic bronchodilator administration in smokers with early COPD (3,592 men; 2,132 women). Average post-bronchodilator FEV1 at entry was 78.4% predicted for men and 78.2% predicted for women; all participants had an FEV1/FVC ratio less than 0.70.Measurements and Main Results: Participants underwent a baseline evaluation and five annual follow-up assessments, including questionnaires and spirometry. The effect of ongoing dust or fume exposure on FEV1 in each follow-up year was statistically evaluated with a mixed-effects regression model, which was adjusted for FEV1 at ...
Performance Characteristics of an Operational WiMAX Network

The term WiMAX is used to refer to a collection of standards, products, and service offerings derived from the IEEE 802.16 family of standards for wireless networks. These standards define physical and MAC layer elements that ensure interoperability of compatible equipment. However, the standards leave both the details of the packet scheduling algorithms and the values of performance related configuration parameters to the discretion of the equipment vendor or network operator. These algorithms and parameters ultimately determine fundamental performance characteristics such as round-trip latency and sustainable throughput on the network. In this paper, we examine performance characteristics of an operational WiMAX testbed upon which we were able to conduct controlled experiments in the absence of competing traffic. We characterize latency, throughput, protocol overhead, and the impact of WiMAX on TCP dynamics. We show that scheduling policies and parameter values impact actual performance in ways that are not possible to characterize in generic studies of WiMAX.
The 3' cis-acting genomic replication element of the severe acute respiratory syndrome coronavirus can function in the murine coronavirus genome

The 3' untranslated region (3' UTR) of the genome of the severe acute respiratory syndrome coronavirus can functionally replace its counterpart in the prototype group 2 coronavirus mouse hepatitis virus (MHV). By contrast, the 3' UTRs of representative group 1 or group 3 coronaviruses cannot operate as substitutes for the MHV 3' UTR.
Fuzzy Diffusion Analysis: Decision Significance and Applicable Scenarios

Distributed Wireless Sensor Networks (WSNs) operate under severe energy constraints and are largely characterized by short-range multi-hop radio communications, which signify the role of energy-efficient routing schemes for such networks. Fuzzy Diffusion, an energy optimization on the general diffusion schemes for application-aware sensor networks, has been shown to offer substantial improvement in WSN lifetime and connectivity. The initial exploration depicted the advantages of extreme conservative routing in dense WSNs. However, a progressive investigation of fuzzy diffusion is needed to address several important aspects of the protocol mechanism and to quantify its applicability. Fuzzy diffusion is primarily based upon energy-aware routing decisions, and so an analysis of the impact of decision-making strategies on the protocol performance is required to substantiate the use of any specific tool. The purpose of this work is to quantify the contribution of fuzzy logic in computing efficient forwarding decisions as compared to simpler, straightforward crisp decision-making strategies. Further, this paper aims at exploring the network and traffic scenarios under which fuzzy diffusion scheme would be efficient, through a series of simulation experiments.
Enhanced Secure Architecture for Joint Action Test Group Systems

The implementation of debugging tools through joint action test group (JTAG) has led to increased exposure of intellectual property through the interface. In this brief, the first hardware implementation of a flexible multilevel access security system for the JTAG interface is detailed. The proposed method is user-privilege aware, which allows for higher granularity for controlling user access of individual scan chains. The loading of individual JTAG instructions into scan chains can be blocked based on the credentials of the user. The hardware modifications proposed are compliant with IEEE 1149.1, have minimal timing overhead, and require no modifications to the core logic of the integrated circuit.
Exploring question subjectivity prediction in community QA

In this paper we begin to investigate how to automatically determine the subjectivity orientation of questions posted by real users in community question answering (CQA) portals. Subjective questions seek answers containing private states, such as personal opinion and experience. In contrast, objective questions request objective, verifiable information, often with support from reliable sources. Knowing the question orientation would be helpful not only for evaluating answers provided by users, but also for guiding the CQA engine to process questions more intelligently. Our experiments on Yahoo! Answers data show that our method exhibits promising performance.
The hb-index, a modified h-index designed to more fairly assess author achievement

The h-index characterizes the publication achievement/impact of authors and is defined by the originator Jorge Hirsch as: ‘the number of papers with citation number ≥h’. The h-index has the inherent characteristic that authors with very different total citations can have the same h-index. In fact, no contributions to the h-index are made either by papers cited fewer times than h, or citations of an individual paper above h. Such citations are ‘excess’ citations not credited by the h-index. To address these deficiencies, we propose a simple, straightforward modification, the hb-index: , where h is the Hirsch h-index and e is the sum of all citations minus h2. Therefore, e is the excess citations not credited by the h-index.
Influence of Synthetic and Processing Parameters on the Surface Area, Speciation, and Particle Formation in Copper Oxide/Silica Aerogel Composites

A systematic study of the effects of pH, precursor salt, and temperature on the surface area, particle size, and copper speciation in 3 wt % CuO in silica aerogels and xerogels has been conducted. The materials were synthesized by copolymerization sol−gel reactions, followed by either supercritical solvent extraction using CO2 (aerogels) or conventional drying (xerogels) and annealing in air. Among the six different copper precursors examined, copper(II) acetate was found to be the best in terms of its stability, solubility, and binding capacity of copper in the silica matrix. Aerogels prepared with copper(II) acetate were found to have considerably higher surface areas than the corresponding xerogels, and the observed formation of CuO particles occurred at higher temperatures (900 vs 650 °C, by TEM analysis). X-ray diffraction of gels annealed at 900 °C likewise revealed the presence of nanocrystalline CuO, with larger particles observed in acid-catalyzed aerogels vs base-catalyzed aerogels (∼26 vs ∼15 n...
Surface Functionalization of Thin-Film Composite Membranes with Copper Nanoparticles for Antimicrobial Surface Properties

Biofouling is a major operational challenge in reverse osmosis (RO) desalination, motivating a search for improved biofouling control strategies. Copper, long known for its antibacterial activity and relatively low cost, is an attractive potential biocidal agent. In this paper, we present a method for loading copper nanoparticles (Cu-NPs) on the surface of a thin-film composite (TFC) polyamide RO membrane. Cu-NPs were synthesized using polyethyleneimine (PEI) as a capping agent, resulting in particles with an average radius of 34 nm and a copper content between 39 and 49 wt.%. The positive charge of the Cu-NPs imparted by the PEI allowed a simple electrostatic functionalization of the negatively charged RO membrane. We confirmed functionalization and irreversible binding of the Cu-NPs to the membrane surface with SEM and XPS after exposing the membrane to bath sonication. We also demonstrated that Cu-NP functionalization can be repeated after the Cu-NPs dissolve from the membrane surface. The Cu-NP functi...
Isolation by high-performance liquid chromatography and quantitation by radioimmunoassay of therapeutic concentrations of digoxin and metabolites

A method combining high-performance liquid chromatography for separation of digoxin from three of its metabolites with subsequent quantitation of each compound by radioimmunoassay is described. The metabolites are shown to interfere with the radioimmunoassay procedure thus providing the need for separation prior to assay.
Omega-3 Fatty Acids and Cardiovascular Disease Prevention: Reality or Mirage?

The marine-derived long chain omega-3 (n-3) polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have a broad spectrum of cardioprotective effects. Over the past three decades, accumulated evidence from both observational and interventional studies have demonstrated that increased intake of fish or fish-derived n-3 PUFAs decreases risk of major cardiovascular disease ( CVD) events. The benefits of eating fish appear to outweigh the potential risk of mercury exposure from consuming fish. Their use, therefore, has been included in the guidelines to prevent CVD in both the general population and in patients with a history of CVD. However, several questions remain regarding their effectiveness in primary prevention, the potential pro-arrhythmic effect, and the optimal dosage needed to achieve the reduction of CVD risk and targeted subpopulation. This article summarizes the most recent scientific data for n-3 PUFAs in the prevention of CVD and risk factors with the aim to address those uncertain areas.
On the computation of integral properties of objects

Abstract This paper discusses computationally efficient methods for evaluating engineering properties of objects on computers. These methods use existing solid modeling techniques that lend themselves to mass property evaluations. An overall review of the quasidisjoint representation methods used for the approximate evaluation of integral properties of solid models is given. These methods of representation are typically used by analysis packages in the calculation of volume, surface area, center of gravity, mass, moment of inertia, etc. The methods are identical to approximate solid modeling techniques whose implementation involves the subdivision of space into subdomains. Finally, the method of cell decomposition is used for the determination of integral properties of solids modeled by a Constructive Solid Geometry (CSG) technique. The method suggested is very practical for microcomputer implementation. Sample numerical results are finally shown to compare the approximated results with the exact values.
Atriogenic Mitral Valve Reflux: Diastolic Mitral Incompetence Following Isolated Atrial Systoles

Cardiac and aortic pressures were recorded after stellate ganglionectomy and vagotomy. Acute heart block was produced by injecting the atrioventricular node, and atrial and ventricular systoles were controlled electronically to occur independently or in any desired relationship. Angiocardiograms recorded on video tape after injections of 4 ml 69% Renovist into the left ventricle were analyzed with a videodensitometer able to detect small refluxes of contrast medium into the left atrium and correlate them with phases of the cardiac cycle. When ventricular driving was temporarily suspended but atrial driving continued, pressure records indicated mitral valve closure after each atrial systole, but reflux of contrast medium into the atrium occurred after each systole not followed by a normally sequenced ventricular systole. Driving with a 2: 1 atrioventricular stimulation resulted in reflux, with the alternate atrial contraction dissociated from ventricular systole. Thus, the mitral valve was not effectively closed by atrial systoles that were not followed by normally sequenced ventricular systoles.
p38 kinase regulates epidermal growth factor receptor downregulation and cellular migration

Internalization and proteolytic degradation of epidermal growth factor (EGF) receptor (R) following ligand binding is an important mechanism for regulating EGF-stimulated signals. Using pharmacological and RNA interference inhibition of p38 mitogen-activated protein kinase, we show that p38 is required for efficient EGF-induced EGFR destruction but not internalization. In the absence of p38 activity, EGF fails to stimulate the ubiquitin ligase Cbl or ubiquitinylation of EGFR, and internalized EGFR accumulates in intracellular vesicles containing caveolin-1. These effects are accompanied by loss of EGFR phosphorylation on Y1045, a phosphorylation site required for Cbl activation. Furthermore, similar to cells treated with p38 inhibitors, intestinal epithelial cells expressing Y1045F EGFR mutants show increased proliferation but not migration in response to EGF, thus uncoupling these biological responses. Together these data position p38 as a modulator of ligand-stimulated EGFR processing and demonstrate that this processing has a profound impact on the cellular outcome of EGFR signaling.
Induction of murine fibrosarcomas by low dose treatment with 3-methylcholanthrene followed by promotion with 12-O-tetradecanoyl-phorbol-13-acetate

Abstract Repeated application of the tumor promoter 12- O -tetradecanoyl phorbol-13-acetate (TPA) to the skin of mice previously treated with an initiating dose of the carcinogen 7,12-dimethylbenz[ a ]anthracene has been shown to lead to an increased incidence of papilloma. The studies presented here describe a modified murine two-stage carcinogenesis model in which a single subcutaneous administration of the carcinogen 3-methylcholanthrene (3-MC) is followed by multiple applications of TPA administered subcutaneously or intraperitoneally. TPA was observed to act as a promoter under these conditions when given either subcutaneously or intraperitoneally. When a carcinogenic dose of 3-MC was administered (0.5 mg/mouse) followed by regular treatment with TPA (10 μg/mouse) the percent of tumor-bearing mice increased and the length of time until tumors developed significantly shortened. At a subcarcinogenic dose of 3-MC (0.025 mg/mouse), repeated treatment with TPA led to tumor development whereas no tumors were observed in mice not treated with TPA. All tumors were found to be fibrosarcomas. Thus, TPA is capable of acting as a systemic promoter of mesenchymally derived tumors.
Flutter Shutter Video Camera for compressive sensing of videos

Video cameras are invariably bandwidth limited and this results in a trade-off between spatial and temporal resolution. Advances in sensor manufacturing technology have tremendously increased the available spatial resolution of modern cameras while simultaneously lowering the costs of these sensors. In stark contrast, hardware improvements in temporal resolution have been modest. One solution to enhance temporal resolution is to use high bandwidth imaging devices such as high speed sensors and camera arrays. Unfortunately, these solutions are expensive. An alternate solution is motivated by recent advances in computational imaging and compressive sensing. Camera designs based on these principles, typically, modulate the incoming video using spatio-temporal light modulators and capture the modulated video at a lower bandwidth. Reconstruction algorithms, motivated by compressive sensing, are subsequently used to recover the high bandwidth video at high fidelity. Though promising, these methods have been limited since they require complex and expensive light modulators that make the techniques difficult to realize in practice. In this paper, we show that a simple coded exposure modulation is sufficient to reconstruct high speed videos. We propose the Flutter Shutter Video Camera (FSVC) in which each exposure of the sensor is temporally coded using an independent pseudo-random sequence. Such exposure coding is easily achieved in modern sensors and is already a feature of several machine vision cameras. We also develop two algorithms for reconstructing the high speed video; the first based on minimizing the total variation of the spatio-temporal slices of the video and the second based on a data driven dictionary based approximation. We perform evaluation on simulated videos and real data to illustrate the robustness of our system.
Method-induced Misclassification for a Respirable Dust Sampled Using ISO/ACGIH/CEN Criteria

The single cut measurement of exposure to respirable dust is the accepted method of exposure classification in occupational hygiene. We previously showed that actual pulmonary tissue dose may be substantially different from the dose expected, or the indicated dose, based on measurements using current single cut methodologies. We now examine exposure misclassification of workers based on any single cut respirable dust measurement using the internationally accepted ISO/ACGIH/CEN single cut respirable dust measurement criteria. Hypothetical aerosols with 12 generalized size distributions typical of the method of aerosol generation (condensation, aged condensation, mechanical low energy, mechanical high energy and mixtures thereof) were assumed. Using previously reported models for sampler penetration and pulmonary deposition, Monte Carlo simulations of actual mass dose to pulmonary tissues in comparison to the dose estimate from an ideal respirable aerosol sampler were carried out. Measurement-based indicated doses were used to classify exposures into five exposure categories and these classifications were compared with the ‘true’ classifications from the dosebased exposure estimates. Misclassification rates were generally severe and were greatest for aerosols with mass median aerodynamic diameter (MMAD) 15 µm. Misclassification rates for oral and nasal breathing at 750 and 1500 ml tidal volume and 15 breaths/min were similar for each aerosol examined.
Crosslinking of isocyanate functional acrylic latex with telechelic polybutadiene. I. Synthesis and characterization

An ambient curable isocyanate functional acrylic latex was synthesized by incorporating dimethyl meta-isopropenyl benzyl isocyanate (TMI®), an isocyanate monomer, into styrene/n-butyl acrylate copolymer. An artificial latex of amino-terminated telechelic polybutadiene was prepared and blended with the acrylic latex as a curing agent. The isocyanate content in the blended latex was determined by titration and FTIR measurements. The latex blend properties, in terms of particle size and latex viscosity, and the latex film properties, in terms of stress-strain behavior and solvent swelling behavior, showed no significant change after 30 days' storage of the latex blend at 50°C. The good storage stability was attributed to the stable nature of the latex blend in which there was little chance for the isocyanate-containing particles to come into contact with the curing agent particles, thus preventing premature contact of the acrylic chains with the telechelic chains. The reactivity of different functional groups in the telechelic polymer was studied; the amino group was found to be the most reactive toward the TMI. In addition, a shorter chain telechelic crosslinker was found to result in a higher degree of crosslinking, but this was more intraparticle than interparticle in nature.
Viral determinants of simian immunodeficiency virus (SIV) virulence in rhesus macaques assessed by using attenuated and pathogenic molecular clones of SIVmac.

To identify viral determinants of simian immunodeficiency virus (SIV) virulence, two pairs of reciprocal recombinants constructed from a pathogenic (SIVmac239) and a nonpathogenic (SIVmac1A11) molecular clone of SIV were tested in rhesus macaques. A large 6.2-kb fragment containing gag, pol, env, and the regulatory genes from each of the cloned (parental) viruses was exchanged to produce one pair of recombinant viruses (designated SIVmac1A11/239gag-env/1A11 and SIVmac239/1A11gag-env/239 to indicate the genetic origins of the 5'/internal/3' regions, respectively, of the virus). A smaller 1.4-kb fragment containing the external env domain of each of the parental viruses was exchanged to create the second pair (SIVmac1A11/239env/1A11 and SIVmac239/1A11env/239) of recombinant viruses. Each of the two parental and four recombinant viruses was inoculated intravenously into four rhesus macaques, and all 24 animals were viremic by 4 weeks postinoculation (p.i.). Virus could not be isolated from peripheral blood mononuclear cells (PBMC) of any animals infected with SIVmac1A11 after 6 weeks p.i. but was consistently isolated from all macaques inoculated with SIVmac239 for 92 weeks p.i. Virus isolation was variable from animals infected with recombinant viruses; SIVmac1A11/239gag-env/1A11 and SIVmac239/1A11env/239 were isolated most frequently. Animals inoculated with SIVmac239 had 10 to 100 times more virus-infected PBMC than those infected with recombinant viruses. Three animals infected with SIVmac239 died with simian AIDS (SAIDS) during the 2-year observation period after inoculation, and the fourth SIVmac239-infected animal had clinical signs of SAIDS. Two animals infected with recombinant viruses died with SAIDS; one was infected with SIVmac239/1A11gag-env/239, and the other was infected with SIVmac1A11/239gag-env/1A11. The remaining 18 macaques remained healthy by 2 years p.i., and 13 were aviremic. One year after inoculation, peripheral lymph nodes of some of these healthy, aviremic animals harbored infected cells. All animals seroconverted within the first few weeks of infection, and the magnitude of antibody response to SIV was proportional to the levels and duration of viremia. Virus-suppressive PBMC were detected within 2 to 4 weeks p.i. in all animals but tended to decline as viremia disappeared. There was no association of levels of cell-mediated virus-suppressive activity and either virus load or disease progression. Taken together, these results indicate that differences in more than one region of the viral genome are responsible for the lack of virulence of SIVmac1A11.
Complete and incomplete revascularization at aortocoronary bypass surgery: experience with 392 consecutive patients.

Abstract This report presents our experience with “complete” and “incomplete” revascularization in 392 consecutive patients undergoing aortocoronary artery bypass surgery. Patients were considered to have had “complete” revascularization only if all major coronary arteries with 70 per cent occlusion received at least one bypass graft. Patients were considered “incompletely” revascularized if any vessel with a 70 per cent or more occlusion did not receive at least one bypass graft. The “completely” revascularized cohort contained 186 patients and the “incompletely” revascularized cohort contained 206 patients. The survival of the “completely” and “incompletely” revascularized cohorts was compared postoperatively and at 6, 12, and 24 months using the Chi-square test. Relief of anginal pain rates were compared at 6, 12, and 24 months using the Chi-square test. Analyses were repeated after stratifying for number of vessels diseased. The subgroup with one vessel diseased was, by definition, “completely” revascularized. No significant difference in survival or relief of anginal pain was demonstrated in the total group or in subgroups with 2 and with 3 vessels diseased. The data indicate that “complete” revascularization is not closely coupled to two-year survival or relief of anginal pain.
Therapeutic Intervention in a Case of Ataxic Dysarthria Associated With a History of Amateur Boxing

The goals of this study were to (a) describe the presenting features of ataxic dysarthria present in a participant with a long history of amateur boxing, (b) describe a novel application of behavio...
Cognitive and neural contributors to emotion regulation in aging

Older adults, compared to younger adults, focus on emotional well-being. While the lifespan trajectory of emotional processing and its regulation has been characterized behaviorally, few studies have investigated the underlying neural mechanisms. Here, older adults (range: 59–73 years) and younger adults (range: 19–33 years) participated in a cognitive reappraisal task during functional magnetic resonance imaging (fMRI) scanning. On each trial, participants viewed positive, negative or neutral pictures and either naturally experienced the image (‘Experience’ condition) or attempted to detach themselves from the image (‘Reappraise’ condition). Across both age groups, cognitive reappraisal activated prefrontal regions similar to those reported in prior studies of emotion regulation, while emotional experience activated the bilateral amygdala. Psychophysiological interaction analyses revealed that the left inferior frontal gyrus (IFG) and amygdala demonstrated greater inverse connectivity during the ‘Reappraise’ condition relative to the ‘Experience’ condition. The only regions exhibiting significant age differences were the left IFG and the left superior temporal gyrus, for which greater regulation-related activation was observed in younger adults. Controlling for age, increased performance on measures of cognition predicted greater regulation-related decreases in amygdala activation. Thus, while older and younger adults use similar brain structures for emotion regulation and experience, the functional efficacy of those structures depends on underlying cognitive ability.
Effect of fatigue and hypohydration on gait characteristics during treadmill exercise in the heat while wearing firefighter thermal protective clothing

This study compared the gait characteristics of individuals walking in heat while wearing firefighting equipment in fatigued and non-fatigued states. Nineteen subjects performed a 50-min treadmill protocol in a heated room while gait patterns were recorded using a digital video camcorder. Forty gait cycles were analyzed near the beginning (9min) and at the end (39-49min) of exercise. Spatio-temporal gait variables including step frequency, step length, swing time, stance time, cycle time and double-support time were determined. Gait variability was quantified by the standard deviation (SD) and coefficient of variation (CV) of each variable. Left-right symmetry was calculated using the symmetry index (SI) and symmetry angle (SA). Paired t-tests (alpha=0.05) were performed to identify difference between the beginning and the end of the protocol for each measured variable. Spatio-temporal gait characteristics did not differ between the beginning and the end of exercise. Gait variability of the double-support time increased at the end as measured by both SD (P=0.037) and CV (P=0.030) but no change was observed for other variables. Left-right symmetry measured using either SI or SA did not differ between sessions. In summary, spatio-temporal gait characteristics and symmetry while wearing firefighting equipment are insensitive to physiological fatigue. Prolonged walking in heat while wearing firefighting equipment may increase gait variability and therefore the likelihood of a fall. Future studies are needed to confirm the potential relationship between fatigue and gait variability and to investigate the possible influence of individual variation. Language: en
Metabolism, longevity and epigenetics.

Metabolic homeostasis and interventions that influence nutrient uptake are well-established means to influence lifespan even in higher eukaryotes. Until recently, the molecular mechanisms explaining such an effect remained scantily understood. Sirtuins are a group of protein deacetylases that depend on the metabolic intermediate NAD+ as a cofactor for their function. For this reason they sense metabolic stress and in turn function at multiple levels to exert proper metabolic adaptation. Among other things, sirtuins can perform as histone deacetylases inducing epigenetic changes to modulate transcription and DNA repair. Recent studies have indicated that beyond sirtuins, the activity of other chromatin modifiers, such as histone acetyl transferases, might also be tightly linked to the availability of their intermediate metabolite acetyl-CoA. We summarize current knowledge of the emerging concepts indicating close crosstalk between the epigenetic machineries able to sense metabolic stress, their adaptive metabolic responses and their potential role in longevity.
Hypolipicllemic Activity of Cyclic lmido Alkyl Ethers, Thioethers, Sulfoxides, and Sulfones

N-Substituted alkyl others, thioethers, sulfoxides, and sulfones of cyclic imides (e.g., phthalimide, saccharin, 1,8-naphthalimide, succinimide, and 2,3-dihydrophthalazine-1,4-dione) were shown to have potent hypolipidemic activity at doses of 10 and 20 mg/kg/d in rodents. These N-substitutions afforded no improvement over other known N-substitutions (e.g., butyl, 3-butanone, or the propionic acid derivatives of phthalimide, saccharin, and 2,3-dihydrophthalazine-1,4-dione) compared with the respective parent compounds. However, 2-(methoxyethyl)-1 H-benz[de]isoquinoline-1,3-(2H)dione (3a), 2-[2-methylsulfinyl]ethyl-1Hbenz[de]isoquinoline-1,3-(2H)dione (3c), 1-(2-methylsulfinyl)-2,5-pyrrolidenedione (4c), and 1-(2-methoxyethyl-2,5-pyrrolidenedione (4a)) significantly improved activity compared with parent compounds, as well as previously reported N-substituted analogues, reducing serum cholesterol levels and serum triglyceride levels by 40%. The thioether of succinimide afforded a 54% reduction of serum cholesterol and a 41% reduction of serum triglyceride levels in mice after 16d. The alkyl thioethers of 1,8-naphthalimide and succinimide significantly lowered cholesterol levels in serum VLDL and LDL, while the alkyl thioethers of succinimide elevated HDL cholesterol content. Tissue lipids were reduced in the liver and aorta by these selected derivatives. The activities of regulatory enzymes in de novo synthesis of hepatic cholesterol and triglyceride were inhibited by the selected 1,8-naphthalimide derivatives. In situ cholesterol and cholic acid reabsorption from intestines were suppressed by the presence of the agents.