cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of Fractal-Like Spore Aggregates Using Direct Simulation Monte Carlo

DOI: 10.2514/1.T3824 The work presented in this paper is a continuation of the authors’ previous efforts to develop a realistic bioengineering model for predicting the survivability of anthrax spores subjected to a high-temperature gas environment. One of the major mechanisms of deactivating spores is to expose them to elevated temperatures, and careful, exposure-tube experiments have been carried out to ascertain the deactivation mechanism. Spores typically exist in nature as aggregates, but simulating the heat transfer to clumps of spores is difficult because of the highly irregular geometry of spore clumps. In this work, the tunable particle-cluster and cluster-cluster algorithms are implemented to generate fractal-like spore aggregates. The algorithm output as a function of algorithm parameter input is compared with a typical spore-clump image. Because the spore aggregate size is small and is on the order of the mean free path even at atmospheric conditions, the direct simulation Monte Carlo method is used to model the heat transfer to each of the spores in the aggregate. The shielding effect of aggregate spores on a single spore in the clump is studied, revealing that, for aggregates on the order of 100, the shielding effect is about 25% 45% compared with a single, isolated spore.
Preserving Edge Position During Resampling

A technique for designing digital filters that preserve edge position during image resampling is described. The technique consists of designing a set of separable filters, with each filter designed as an all pass filter with nonlinear phase and a set constrained amplitude. The technique is compared to existing techniques.
Sparse linear filters for detection and classification in hyperspectral imagery

We investigate the use of convex optimization to identify sparse linear filters in hyperspectral imagery. A linear filter is sparse if a large fraction of its coefficients are zero. A sparse linear filter can be advantageous because it only needs to access a subset of the available spectral channels, and it can be applied to high-dimensional data more cheaply than a standard linear detector. Finding good sparse filters is nontrivial because there is a combinatorially large number of discrete possibilities from which to choose the optimal subset of nonzero coefficients. But, by converting the optimality criterion into a convex loss function, and by employing an L1 penalty, one can obtain sparse solutions that are globally optimal. We investigate the performance of these sparse filters as a function of their sparsity, and compare the convex optimization approach with more traditional alternatives for feature selection. The methodology is applied both to the adaptive matched filter for weak signal detection, and to the Fisher linear discriminant for terrain categorization.
Comparison of Heritability Estimates from Daughter on Dam Regression with Three Models to Account for Production Level of Dam

Three models were used to estimate heritabilities for milk yields at different production levels and for different years as twice the regression of daughter residual effects on dam residual effects. The denominator is the residual mean square for dams. The numerator is the difference between the residual term for sum of dam's and daughter's records and sum of residual terms for records of dams and daughters. Model 1 included sire of daughter and herd-year-season of daughters only. Model 2 included sire of daughter, herd-year-season of dam, and herd-year-season of daughter. Model 3 included sire of daughter and herd-year-season of dam and herd-year-season of daughter combination. The weighted mean estimates for each method were, respectively, .35, .38, .38 for milk production and .61, .67, .67 for fat test. Yearly time trends in heritability were slightly positive for both milk production and fat test. Standard errors of heritability estimates from model 1 were 40 to 50% smaller than those from models 2 and 3 due to the smaller number of effects in the model. Estimates for model 2 from low to high production levels averaged .30, .38, .38, and .42 for milk yield and .64, .68, .67, and .71 for fat test.
Active3He activation analysis for carbon and oxygen

The surface and body concentrations of carbon and oxygen have been measured in various materials using prompt3He activation techniques. This target excitation functions were determined for (3He, p) reactions with carbon and oxygen over a3He energy range from 2.5 to 9.0 MeV. These data were used in the calculations of activation curves for various combinations of incident particle energy, impurity distributions, and material. Information on a computer code that was used in the analysis of the data is presented.
Determination of traces of streptomycin and related antibiotics by adsorptive stripping voltammetry

Adsorptive stripping voltammetry provides sensitive determinations of trace amounts of the saccharide-related antibiotics, streptomycin, erythromycin and novobiocin. A static mercury drop electrode is immersed in a stirred alkaline solution of the drug for a fixed time (60–300 s) at a suitable potential, and the adsorbed species is then stripped in the linear-scan or differential-pulse mode. The preconcentration potentials and stripping peak potentials (vs. Ag/AgCl) are, respectively, −1.0 V and −1.58 V for streptomycin, −0.9 V and −1.2 V for erythromycin, and −1.0 V and −1.38 V for novobiocin. The interfacial behavior is discussed. Short preconcentration periods suffice to quantity streptomycin, novobiocin, and erythromycin down to the 7 × 10−10 M, 2.5 × 10−9 M, and 1.3 × 10−8 M levels, respectively. Streptomycin added to urine can be quantified after simple dilution.
Analysis for Public Policy at the State and Regional Levels The Role of Think Tanks

Think tanks (policy research institutes) in the U.S. have played a role in policy making for almost 100 years, though most date from after WWII. At the state level, however, they have been much les...
Breast biopsy and distress: feasibility of testing a Reiki intervention.

Purpose: The purpose of this randomized pilot was to determine feasibility of testing Reiki, a complementary therapy intervention, for women undergoing breast biopsy (BB). Background: Increasingly women face the possibility of BB, the definitive test for breast cancer. Psychological distress associated with BB includes anxiety and depression. Reiki was proposed as an intervention to decrease anxiety and promote relaxation. Method: Thirty-two women scheduled for BB were randomized to Reiki intervention versus conventional care control. Anxiety and depression were evaluated using self-report questionnaires. Findings: Analysis found no significant mean differences between groups over time. Comparably low baseline anxiety levels (possible selection bias) decreased naturally with time allowing little room for observing treatment effect. Conclusions: Reiki, when administered in the naturalistic setting of a complementary therapy office, did not suggest evidence of efficacy. An intervention offered within the bo...
Fine needle aspiration biopsy in the management of children and young adults with peripheral lymphadenopathy

To determine the effectiveness of fine needle aspiration (FNA) of the lymph node in the management of young patients with peripheral lymphadenopathy, all patients 30 years of age and under who had a lymph node aspirate and who then had subsequent excisional biopsy, autopsy, or clinical follow-up for a minimum of one year were examined. One hundred twenty-seven aspirates from one hundred twenty-six patients fulfilled the criteria of the study. Diagnoses of eighty-three benign and thirty-seven malignant lymphadenopathies were confirmed. There were three false negative and four false positive diagnoses. Sensitivity, specificity, and positive and negative predictive values were 0.93, 0.95, 0.90, and 0.97%, respectively. Of the one hundred twenty-six patients, twenty-five had a previous history of malignancy. Results of aspiration biopsy in this group were examined to determine FNA ability to predict recurrent disease. In this group the sensitivity, specificity and positive and negative predictive values were 0.95, 0.80, 0.95, and 0.80 respectively, Finally, the group of patients with clinically suspicious primary lymphadenopathy without an antecedent history of malignancy were examined to determine the effectiveness of the technique for selecting patients for surgical biopsy. This group included a total of one hundred two patients. Sensitivity, specificity, and positive and negative predictive values were 0.93, 0.96, 0.90, and 0.97, respectively. Based on the data from this retrospective study, we conclude that fine needle aspiration provides a useful tool in the management of young patients with peripheral lymphadenopathy, both in monitoring recurrent disease and in triaging patients with clinically suspicious primary lymphadenopathy to determined the next appropriate step in management.
An assessment of methods used for measuring the recovery of mammalian cells from freezing and thawing.

Abstract Traditional methods of determining cell viability (vital dye staining and plating efficiency) as a measure of recovery from freeze-thaw cycles were found particularly unsuitable for human diploid cell lines. A modified plating efficiency method (RI) and a method using the release of radiochromate from injured or dead cells were compared and assessed for their suitability as measurements of cell recovery from freezing and thawing.
An Integrated Web Resource for Cotton

"The Cotton Diversity Database" (http://cotton.agtec.uga.edu) is a Web resource for cotton (Gossypium spp.) phenotypic and genomic data. A primary goal for this resource is to provide both a useful management tool for breeders and other applied scientists and a research tool for genetic and genomic scientists. The resource contains four interface suites that include displays for each of the available phenotypic or genomic data types. These display suites are accessible via the genotype portal, a search interface that allows users to begin with a cotton accession and obtain all available data. The phenotypic data displays include graphical views of overall cultivar performance with means and between group standard deviations indicated in an easy-to-interpret graphical manner for common trial measures such as lint yield, micronaire, etc. The genomic data displays include interactive graphical views of genetic map and diversity data types. Genetic map data is displayed in both traditional linear and two-dimensional comparative dot plot formats. Genetic diversity data is displayed in an interactive tree-based format showing degrees of similarity among genotypes. The data are stored in Oracle relational database (RDBMS) schemas containing tables and views for data storage, auto-calculated statistics and display parameters. The searchable RDBMS provides flexibility for a wide range of query and search options as well as integration paths amongst the various data types.
Utilization of computer processed high definition video imaging for measuring motility of microscopic nematode stages on a quantitative scale: "The Worminator".

A major hindrance to evaluating nematode populations for anthelmintic resistance, as well as for screening existing drugs, new compounds, or bioactive plant extracts for anthelmintic properties, is the lack of an efficient, objective, and reproducible in vitro assay that is adaptable to multiple life stages and parasite genera. To address this need we have developed the “Worminator” system, which objectively and quantitatively measures the motility of microscopic stages of parasitic nematodes. The system is built around the computer application “WormAssay”, developed at the Center for Discovery and Innovation in Parasitic Diseases at the University of California, San Francisco. WormAssay was designed to assess motility of macroscopic parasites for the purpose of high throughput screening of potential anthelmintic compounds, utilizing high definition video as an input to assess motion of adult stage (macroscopic) parasites (e.g. Brugia malayi). We adapted this assay for use with microscopic parasites by modifying the software to support a full frame analysis mode that applies the motion algorithm to the entire video frame. Thus, the motility of all parasites in a given well are recorded and measured simultaneously. Assays performed on third-stage larvae (L3) of the bovine intestinal nematode Cooperia spp., as well as microfilariae (mf) of the filarioid nematodes B. malayi and Dirofilaria immitis, yielded reproducible dose responses using the macrocyclic lactones ivermectin, doramectin, and moxidectin, as well as the nicotinic agonists, pyrantel, oxantel, morantel, and tribendimidine. This new computer based-assay is simple to use, requires minimal new investment in equipment, is robust across nematode genera and developmental stage, and does not require subjective scoring of motility by an observer. Thus, the “Worminator” provides a relatively low-cost platform for developing genera- and stage-specific assays with high efficiency and reproducibility, low labor input, and yields objective motility data that is not subject to scorer bias.
Proton-Ionizable Crown Compounds: Transport of Alkali and Alkaline Earth Cations Using Proton-Ionizable Triazolo Macrocycles

Abstract The macrocycle-mediated flaxes of the alkali and alkaline earth metal cations have been determined in a H2O-CH2Cl2-H2O bulk liquid membrane system. Water-insoluble proton-ionizable macrocycles of the triazolo type were used. The proton-ionizable feature allows the coupling of cation transport to reverse H+ transport. This feature offers promise for the effective separation and/or concentration of alkali metal ions with the metal transport being driven by a pH gradient. A counter anion in the source phase is not co-transported. Transport of the alkali cations only occurred when the source phase pH was greater than the aqueous pKa value for the carriers. Transport increased regularly with increasing source phase pH. Transport of alkaline earth cations from neutral pH source phases was minimal. The alkali cation selectivity order was K+ > Rb+ > Cs+ > Na+ > Li+ for the l8-crown-6 sized macrocycles, while little selectivity was observed with the 15-crown-5 sized macro-cycle.
The stationary bootstrap

Abstract This article introduces a resampling procedure called the stationary bootstrap as a means of calculating standard errors of estimators and constructing confidence regions for parameters based on weakly dependent stationary observations. Previously, a technique based on resampling blocks of consecutive observations was introduced to construct confidence intervals for a parameter of the m-dimensional joint distribution of m consecutive observations, where m is fixed. This procedure has been generalized by constructing a “blocks of blocks” resampling scheme that yields asymptotically valid procedures even for a multivariate parameter of the whole (i.e., infinite-dimensional) joint distribution of the stationary sequence of observations. These methods share the construction of resampling blocks of observations to form a pseudo-time series, so that the statistic of interest may be recalculated based on the resampled data set. But in the context of applying this method to stationary data, it is natural...
Broken or maladaptive? Altered trajectories in neuroinflammation and behavior after early life adversity

Exposure to adversity and stress early in development yields vulnerability to mental illnesses throughout the lifespan. Growing evidence suggests that this vulnerability has mechanistic origins involving aberrant development of both neurocircuitry and neuro-immune activity. Here we review the current understanding of when and how stress exposure initiates neuroinflammatory events that interact with brain development. We first review how early life adversity has been associated with various psychopathologies, and how neuroinflammation plays a role in these pathologies. We then summarize data and resultant hypotheses describing how early life adversity may particularly alter neuro-immune development with psychiatric consequences. Finally, we review how sex differences contribute to individualistic vulnerabilities across the lifespan. We submit the importance of understanding how stress during early development might cause outright neural or glial damage, as well as experience-dependent plasticity that may insufficiently prepare an individual for sex-specific or life-stage specific challenges.
ORIGINAL ARTICLES: Definitive Classes of Childhood Supratentorial Neuroglial Tumors

Our objective in this study was to identify histologically homogenous classes of childhood supratentorial neuroglial tumors. Previously, we identified five quantitative histologic factors (differing linear combinations of 17 reliably recognized histologic features in neuroglial tumors). They account for much of the histologic variance in the 703 supratentorial tumors in the Childhood Brain Tumor Consortium (CBTC) database. In this study, we used the scores on the factors in cluster analyses and identified eight classes of neuroglial tumors. Each of these classes had significant differences in histology, allowing the separation of many of the conventional types of neuroglial tumors into two or more classes. For instance, fibrillary astrocytoma, pilocytic astrocytoma, subependymal giant cell astrocytoma, anaplastic astrocytoma, oligodendroglioma, and ependymoma were represented in two or more classes. Often these classes had statistically significant differences in survival distributions. For instance, the two classes of “anaplastic astrocytomas” have widely discrepant 5-year survival probabilities of 0.7 and 0.2. Use of the classes identified in this study ensures relatively homogeneous histologic subsets of tumors. We suggest that these classes will be useful for the selection of children for therapeutic clinical trials.
Noninvasive monitoring of muscle damage during reloading following limb disuse

Cast immobilization causes skeletal muscle disuse atrophy and an increased susceptibility to muscle damage. The objective of this study was to explore the utility of noninvasive magnetic resonance (MR) imaging to monitor muscle damage in the lower hindlimb muscles of the mouse during reloading following cast immobilization and to compare the findings in different muscles. The hindlimbs of C57BL6 mice were immobilized for 2 weeks in plantarflexion using a bilateral casting model. Following immobilization the mice were allowed to reambulate and muscle damage was monitored at different times. Cage-restricted reloading following cast immobilization induced a significant shift (P < 0.0001) in the transverse (T2) relaxation characteristics of the postural slow-twitch soleus muscle, but not in the neighboring gastrocnemius. Soleus T2 values peaked at 2 days of reloading. Muscle-specific changes in MR T2 relaxation properties correlated with uptake of Evans blue dye, a histological marker of muscle damage. This study demonstrates that T2 MR imaging can be implemented to monitor noninvasively and sequentially muscle-specific damage during reloading following limb disuse.
Thrombin clotting time and fibrinogen concentration in patients treated with coumadin

Thrombin clotting times and fibrinogen levels were measured in plasma from patients on chronic coumadin therapy who had prolonged prothrombin times. Thrombin clotting times were usually prolonged. Fibrinogen concentrations were generally elevated, but some were normal or even low. There was no evidence for disseminated intravascular coagulation. Comparison of thrombin clotting times and fibrinogen levels in normal plasma demonstrates that as fibrinogen concentration increases the thrombin clotting time lengthens. A similar correlation was found in many of the patients tested.
Tumoral calcinosis in the cervical spine in a patient with CREST syndrome. A case report.

T umoral calcinosis is characterized by tumor-like periarticular deposits of calcium, and it commonly presents as a growing calcific mass in the soft tissue surrounding major joints1-6. It may be associated with bone erosion and destruction and may have a mass effect on neurovascular structures7-9. Tumoral calcinosis can be a component of CREST syndrome, an acronym for calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia. Spinal and paraspinal tumoral calcinosis has been reported to involve both the vertebral bodies and the posterior elements of the cervical, thoracic, and lumbar spine6,10-18. To our knowledge, tumoral calcinosis of the cervical spine as a component of CREST syndrome has been reported in only three patients7,8,10. The diagnosis of tumoral calcinosis in the spine is difficult because of its rarity and its ability to mimic a neoplasm or infectious cause6,14,16,19. Neurologic deficits by mass effect can occur and may manifest as radiculopathy and/or myelopathy7-10,18. Moreover, it has been shown that tumoral calcinosis of the spine has presented diagnostic dilemmas to clinicians, radiologists, and pathologists because of a lack of familiarity with the entity16. We report the clinical presentation, radiographic findings, histopathologic results, and the surgical management of tumoral calcinosis of the cervical spine in a patient with CREST syndrome. Our patient is unique in that there was radiographic evidence of rapid progression of bone erosion and crystal deposition involving the posterior elements and paraspinal tissues within a one-year period. In addition, an anomalous, single vertebral artery on the affected side supplied the basilar artery system. The patient was informed that data concerning the case would be submitted for …
Base stacking controls excited-state dynamics in A·T DNA

Solar ultraviolet light creates excited electronic states in DNA that can decay to mutagenic photoproducts. This vulnerability is compensated for in all organisms by enzymatic repair of photodamaged DNA. As repair is energetically costly, DNA is intrinsically photostable. Single bases eliminate electronic energy non-radiatively on a subpicosecond timescale1, but base stacking and base pairing mediate the decay of excess electronic energy in the double helix in poorly understood ways. In the past, considerable attention has been paid to excited base pairs2. Recent reports have suggested that light-triggered motion of a proton in one of the hydrogen bonds of an isolated base pair initiates non-radiative decay to the electronic ground state3,4. Here we show that vertical base stacking, and not base pairing, determines the fate of excited singlet electronic states in single- and double-stranded oligonucleotides composed of adenine (A) and thymine (T) bases. Intrastrand excimer states with lifetimes of 50–150 ps are formed in high yields whenever A is stacked with itself or with T. Excimers limit excitation energy to one strand at a time in the B-form double helix, enabling repair using the undamaged strand as a template.
Flood Basalt Volcanism During the Past 250 Million Years

A chronology of the initiation dates of major continental flood basalt volcanism is established from published potassium-argon (K-Ar) and argon-argon (Ar-Ar) ages of basaltic rocks and related basic intrusions. The dating is therefore independent of the biostratigraphic and paleomagnetic time scales. Estimated errors of the initiation dates of the volcanic episodes determined from the distributions of the radiometric ages are, approximately, + or - 4 percent. There were 11 distinct episodes during the past 250 million years. Sometimes appearing in pairs, the episodes have occurred quasi-periodically with a mean cycle time of 32 + or - 1 (estimated error of the mean) million years. The initiation dates of the episodes are close to the estimated dates of mass extinctions of marine organisms. Showers of impacting comets may be the cause.
The Effect of Zirconia Reinforcing Agents on the Microstructure and Mechanical Properties of Hydroxyapatite-Based Nanocomposites

A hydrothermally treated zirconia colloid was introduced during the precipitation of hydroxyapatite (HAP) to achieve an HAP–zirconia nanocomposite. High dispersion of zirconia was achieved at zirconia loadings below 8 wt%. Vickers hardness was optimized with a 1.5 wt% loading of zirconia. A low loading (1.5 wt%) of tetragonal zirconia was able to increase the bending strength of nanocrystalline HAP from 183 to 243 MPa. This HAP–zirconia nanocomposite was sintered to full density by 1000°C under an applied load of 50 MPa. The average grain sizes of HAP and zirconia were maintained at ≤100 nm. With the high strength and low loading of secondary phase, these HAP-based nanocomposites should be attractive for orthopedic and dental implant applications.
Characterization of the material properties of rat brain stem from indentation tests

The main objective of the present study is to characterize the viscoelastic properties of rat brain stem using an indentation technique. The viscoelastic formulation for a flat indenter was verified with finite element analysis and its limitations were determined. The results showed that up to 30% effective shear strain, the material behavior was linear viscoelastic.
A 1 GHz, low-phase-noise CMOS frequency synthesizer with integrated LC VCO for wireless communications

A 1 GHz, low-phase-noise CMOS frequency synthesizer with an on-chip LC VCO is presented. The synthesizer has 64 programmable frequency channels with a frequency resolution of f/sub ref//64 and the phase noise of -110 dBc/Hz at a 200 kHz offset frequency. The reference sideband spurs are -73.5 dBc. The prototype is implemented in a 0.5 /spl mu/m CMOS process with three metal layers. The active chip area is 3.2 mm/sup 2/ and the prototype dissipates 43 mW, including the VCO buffer power dissipation, from a 3.3 V supply voltage.
How do housing wealth effects vary with age

This article investigates whether the housing wealth effect is constant across age. The data are drawn from the Panel Study of Income Dynamics (PSID) for the waves of 2001, 2003 and 2005. Using threshold estimation to endogenously split the sample by age group, we find three threshold age groups of 49, 55 and 65. Housing wealth has a significant and positive effect on the consumption for individuals aged 49 and 55 years, but a negative effect for individuals aged 65 years and older. If age is below 49 or between 55 and 65 years, the housing wealth effect is insignificant.
PROBENECID IN HYPOPARATHYROIDISM: ABSENCE OF PHOSPHATURIC RESPONSE

The administration of probenecid to each of 4 hypoparathyroid patients during the measurement of specific renal functions did not alter the renal excretion of phosphorus, the clearance of phosphorus, or the concentration of phosphorus in the serum. In contrast, the administration of p-aminohippurate to 3 of these subjects was followed by an increased renal excretion of phosphorus, an increased clearance of phosphorus, and a lower concentration of phosphorus in the serum. These data do not permit the conclusion that probenecid therapy induces a phosphaturic response in hypoparathyroid subjects by interfering with the renal tubular absorption of phosphorus.
On the Adsorption of CaOH+ and BaOH+ by Clays and Soils

Uber die Sorption von BaOH+ und CaOH+ durch Tone und Boden Ein Ton (Wyoming Bentonit), ein Boden (Yolo Lehm von Davis, Kalifornien) und funf verschiedene griechische Boden wurden mit Ba++ und Ca++ (Behandlung mit Ba(OH)2 und Ca(OH)2 unter CO2-freier Luft) gesattigt. Die adsorbierte Barium- und Calciummenge wurde sowohl mittels isotopischer Verdunnung als auch aus Gesamtkationenmenge und Gesamthydroxidmenge bestimmt. Das adsorbierte Barium oder Calcium zeigte in beiden Fallen fast die gleichen Werte. Aus diesen Ergebnissen kann man schliesen, das eine Adsorption von CaOH+- und BaOH+-Kationen sehr wahrscheinlich nicht stattgefunden hat.
The relationship of platelet coagulant activities to venous thrombosis following hip surgery.

Platelets have recently been shown to trigger intrinsic coagulation by two alternative pathways, protect active clotting factors from inactivation by plasma inhibitors and catalyse intrinsic coagulation reactions on the platelet surface to form fibrin. To determine whether these platelet coagulant activities (PCA) might have a role in the pathogenesis of DVT, 29 patients have been studied before and after arthroplasty or other surgery for fractured hip or degenerative hip disease. The occurrence of DVT was detected by [125I]fibrinogen uptake in the legs and confirmed by venography. In patients who developed DVT, all PCA increased progressively and significantly on day 1 (mean rise, 146% of baseline), day 3 (228%) and day 5 (298%) after surgery before isotopic evidence of DVT appeared (mean 3.27 days postoperatively). In patients without DVT no changes in PCA were observed. Plasma coagulation factor assays were no different in patients with and without DVT. Platelet counts and total platelet antiheparin activity increased during the early postoperative period in DVT patients but not in patients without DVT. It is suggested that progressive increases in PCA concerned with triggering and catalysing intrinsic coagulation reactions may play a pathogenetic role in DVT after hip surgery.
Optical couplers in silicon-on-insulator technology

Summary form only given. Silicon-on-insulator technology promises improved performance for CMOS integrated circuits. Due to their unique optical properties, SOI structures offer the ability to integrate long-wavelength photonic devices into the CMOS integrated circuits. A 5/spl times/9 star coupler was fabricated with rib waveguide widths of 4 /spl mu/m and rib height of 2.0 /spl mu/m. Each waveguide is composed of a straight and a curved section followed by a radial section directed toward the center of the opposite array.
Acute effects of nonexcitatory electrical stimulation during systole in isolated cardiac myocytes and perfused heart

Application of electrical field to the heart during the refractory period of the beat has been shown to increase the force of contraction both in animal models and in heart failure patients (cardiac contractility modulation, or CCM). A direct increase in intracellular calcium during CCM has been suggested to be the mechanism behind the positive inotropic effect of CCM. We studied the effect of CCM on isolated rabbit cardiomyocytes and perfused whole rat hearts. The effect of CCM was observed in single cells via fluorescent measurements of intracellular calcium concentration ([Ca 2+ ]i) and cell length (L). Cells were paced once per second throughout these recordings, and CCM stimulation was delivered via biphasic electric fields of 20 ms duration applied during the refractory period. CCM increased the peak amplitude of both [Ca 2+ ]i and L for the first beat during CCM compared to control, but then [Ca 2+ ]i and L decayed to levels lower than the control. During CCM, all contractions had a faster time to peak for both [Ca 2+ ]i and L; after stopping CCM the rise times returned to control levels. In the whole rat heart, the positive inotropic effect of CCM stimulation on left ventricular pressure was completely abolished in the presence of metoprolol, a beta-1 adrenergic blocker. In summary, the CCM-induced changes in intracellular calcium handling by cardiomyocytes did not explain the sustained positive inotropic effect in the whole heart and the b-adrenergic pathway may be involved in the CCM mechanism of action.
Identification of new commercials using repeated video sequence detection

Automated commercial detection can be performed by matching features extracted from commercials or by detecting embedded codes that are hidden within the commercial. In both cases, it is necessary to create a database of known commercials that contain the information necessary for detection. In this paper, we present an automated technique for locating previously unknown commercials by continuously monitoring broadcast television signals. Our system has two components: repeated video sequence detection, and feature-based classification of video sequences as commercials or non-commercials. Our system utilizes customized temporal video segmentation techniques to automatically partition the digital video signal into semantically sensible shots and scenes. As each frame of the video source is processed, we extract auxiliary information to facilitate repeated sequence detection. When the video transition marking the end of the shot/scene is detected, we are able to rapidly locate all previous occurrences of the video clip. In order to classify video sequences as commercials or non-commercials, we extract a number of features from each video sequence that characterize the temporal and chromatic variations within the clip. We have evaluated three classification approaches using this information and have consistently achieved over 90% accuracy identifying new commercials and non-commercials as they are broadcast.
Long-Term Third-Body Effects via Double Averaging

Westudy thelong-term effects of a third body on a satelliteof negligiblemass. Wehavein mind to study thelunisolar effects on an Earth satellite but many other applications can be imagined. We begin with the representation of the disturbing function in an ine nite series in Legendre polynomials but we truncate it at the second-degree terms. Our approach consists of a double analytic averaging: with the period of the satellite and with the period of the third body. We concentrate on using the two important integrals (energy and angular momentum ) to discuss and classify properties of the perturbed orbits of the satellite. For inclinations below 39 deg, the perigee of the orbits always circulates. There are circular and elliptic orbits but the eccentricity does not vary much. For the inclinations above 39 deg, the circular orbits are unstable and the eccentricities can increase rapidly but we have the appearance of new stableorbits: two ellipticfrozen orbits with constant eccentricity and e xed perigee location, at either 90 or 270 deg.
The genesis of carbon-supported Fe-Mn and K-Fe-Mn catalysts from stoichiometric metal carbonyl clusters I. Characterization by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS)

The thermal decomposition of Fe{sub 3}(CO){sub 12}, NEt{sub 4}(Fe{sub 2}Mn(CO){sub 12}), Mn{sub 2}(CO){sub 10}, K(HFe{sub 3}(CO){sub 11}), and K(Fe{sub 2}Mn(CO){sub 12}) has been studied for the first time by dispersing these clusters on an oxygen-free carbon surface and monitoring their behavior by diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS). The Fe{sub 3}(CO){sub 12} decomposed to Fe(CO){sub 5} in either He or H{sub 2}, while Mn{sub 2}(CO){sub 10} decarbonylated without the formation of any stable intermediate clusters in either gas. The NEt{sub 4}(Fe{sub 2}Mn(CO){sub 12}) clusters decomposed with no formation of other stable carbonyl products in He, but in H{sub 2} they formed Mn{sub 2}(CO){sub 10} and (HFe{sub 4}(CO){sub 13}){sup {minus}} species. Similarly, the decomposition of K(Fe{sub 2}Mn(CO){sub 12}) in He produced no detectable intermediates, but under H{sub 2} it led to the formation of these same two intermediate clusters, while K(HFe{sub 3}(CO){sub 11}) yielded (HFe{sub 4}(CO){sub 13}){sup {minus}}. First-order rate constants of decomposition were determined for each cluster, compared to literature k{sub 1} values for nucleophilic substitution reactions in solution, and found to be similar to substitution rate constants for Fe{sub 3}(CO){sub 12} and Mn{sub 2}(CO){sub 10} but higher than those for Fe(CO){sub 5}. The rate-determining step in either themore » substitution or the decomposition reaction appears to be the removal of the first CO ligand in Fe{sub 3}(CO){sub 12}, but with Mn{sub 2}(CO){sub 10} it is Mn-Mn bond scission. The activation energies of decomposition were 18-21 kcal/mol for Fe{sub 3}(CO){sub 12} and 32-40 kcal/mol for Mn{sub 2}(CO){sub 10}, while those for the decomposition products gave intermediate values. This study represents a portion of the first successful application of an IR spectroscopic technique to characterize carbon-supported metal catalysts. 120 refs.« less
Variability of onset times within and among relaxant regimens.

Abstract Study Objective : To evaluate the consistency of times to 95% twitch height depression (T 95% ) in groups of patients receiving identical induction and relaxant regimens. Design : Prospective, noncontrolled, blinded study. Setting : Ambulatory sifgical unit at a university medical center. Patients : Seventy-five ASA physical status I and II patients undergoing general endotracheal anesthesia. Interventions : Patients received succinylcholine 1.5 m.g/kg or a nondepolarizing regimen with doses ranging from approximately 1.5 to 6 times the ED 95 , with or without a priming dose. Measurements and Main Results : For each of the eight relaxant regimens used in five or more patients, the intraregimen variability of T 95% (at the adductor pollicis muscle upon ulnas stimulation at 0.1 Hz) was expressed as SD and range, and the individual data points were displayed. There was wide intraregimen variability. For each. regimen, the slowest T 95% was at least 73% longer than the fastest T 95% For the 16 patients receiving a priming dose plus an intubating dose 5 or more tunes the ED 95 the median T 95% was 95 seconds; however, T 95% , was beyond 120 seconds in 5 of tire 16 cases. Conclusions : The wide variability in onset times among subjects receiving the souse regimen indicates that monitoring of neuromuscular response, preferably to a relatively slow rate of neurostimulation, is essential q 'one elects to use moderate to high doses of atracurium and/or vecuronium,for rapid-sequence induction in a patient in wham movement or coughing is unacceptable. Since onset times were not symmetrical about the mean, the magnitude and frequency of unacceptable onset times would not be fully appreciated unless the individual data points were displayed. Such information may be critical when, reporting the suitability of a neuromuscular blocking drug for rapid intubation.
Multiple jeopardy: Risk and protective factors among addicted mothers' offspring

Objectives of this study were to ascertain risk and protective factors in the adjustment of 78 school-age and teenage offspring of opioid- and cocaine-abusing mothers. Using a multimethod, multiinformant approach, child outcomes were operationalized via lifetime psychiatric diagnoses and everyday social competence (each based on both mother and child reports), and dimensional assessments of symptoms (mother report). Risk/protective factors examined included the child sociodemographic attributes of gender, age, and ethnicity, aspects of maternal psychopathology, and both mother's and children's cognitive functioning. Results revealed that greater child maladjustment was linked with increasing age, Caucasian (as opposed to African American) ethnicity, severity of maternal psychiatric disturbance, higher maternal cognitive abilities (among African Americans) and lower child cognitive abilities (among Caucasians). Limitations of the study are discussed, as are implications of findings for future research.
Fast polylog-time reconfiguration of structurally fault-tolerant multiprocessors

We present a general methodology for the design of structurally k-fault-tolerant multiprocessors that can reconfigure quickly and in a distributed manner around any k processors faults. Structural fault tolerance is defined as the ability of the multiprocessor to reconfigure around faults in order to retain its original interconnection structure; this prevents any performance degradation when faults occur. The basic methodology used here is a generalization of the node covering approach that was introduced by Dutt and Hyes in (1992). The reconfiguration time of previous node-covering designs is linear in the number of processors, which, though faster than those of other designs, can be too slow for many application environments. In this paper, we present new types of node-covering designs that have configuration times T/sub R/ in the range {/spl Theta/(x log (N/x))}, where x is a design parameter that can range of 1 to N, and N is the number of processors. These designs also naturally present a hardware-cost to reconfiguration-time tradeoff; however, the extra hardware cost is nominal even for the fastest reconfiguring designs. We also suggest strategies for efficiently laying out these fast-reconfiguring designs in order to minimize the total wiring area. >
Alpha effect of Alfven waves and current drive in reversed-field pinches

Circularly polarized Alfven waves give rise to an α-dynamo effect that can be exploited to drive parallel current. In a “laminar” magnetic the effect is weak and does not give rise to significant currents for realistic parameters (e.g., in tokamaks). However, in reversed-field pinches (RFPs) in which magnetic field in the plasma core is stochastic, a significant enhancement of the α effect occurs. Estimates of this effect show that it may be a realistic method of current generation in the present-day RFP experiments and possibly also in future RFP-based fusion reactors.
Shear instability in shallow water

This study considers the linear stability of shear flows in shallow water. It explores instabilities related to the classical incompressible (Rayleigh) instability, and those caused by the over-reflection of surface gravity waves. Numerical solutions of the linear stability problem are presented, together with analytical arguments elucidating the role of finite potential vorticity gradients. The slow development of marginally unstable modes is considered for almost inviscid flows. This is described by an evolution equation for the amplitude of the unstable mode, coupled to a critical-layer potential vorticity equation. This reduced system presents a compact description of the linear stability problem and allows exploration of viscous effects.
HOME BIAS IN GOVERNMENT SPENDING AND QUASI NEUTRALITY OF FISCAL SHOCKS

We show how introducing home bias in government spending in the redux model generates quasi neutrality of fiscal policy shocks. We offer an intuitive explanation for this result and we stress its policy implications.
LC/MS/MS method for analysis of E2 series prostaglandins and isoprostanes

15-series prostaglandins (PGE2s) and isoprostanes (isoPGE2s) are robust biomarkers of oxidative stress, possess potent biological activity, and may be derived through cyclooxygenase or free radical pathways. Thus, their quantification is critical in understanding many biological processes where PG, isoPG, or oxidative stress are involved. LC/MS/MS methods allow a highly selective, sensitive, simultaneous analysis for prostanoids without derivatization. However, the LC/MS/MS methods currently used do not allow for simultaneous separation of the major brain PGE2/D2 and isoPGE2 without derivatization and multiple HPLC separations. The developed LC/MS/MS method allows for the major brain PGE2/PGD2/isoPGE2 such as PGE2, entPGE2, 8-isoPGE2, 11β-PGE2, PGD2, and 15(R)-PGD2 to be separated and quantified without derivatization. The method was validated by analyzing free and esterified isoPGE2 in mouse brains fixed with head-focused microwave irradiation before or after global ischemia. Using the developed method, we report for the first time the esterified isoPGE2 levels in brain tissue under basal conditions and upon global ischemia and demonstrate a nonreleasable pool of esterified isoPG upon ischemia. In addition, we demonstrated that PGE2s found esterified in the sn-2 position in phospholipids are derived from a free radical nonenzymatic pathway under basal conditions. Our method for brain PG analysis provides a high level of selectivity to detect changes in brain PG and isoPG mass under both basal and pathological conditions.
Novel Mechanism for the Dissociation of H2O and the Diffusion of O and H along the aAl2O3 (0001) Surface

Based on density functional theory - generalized gradient approximation calculations (DFT-GGA), we provide a theoretical model for the effect of the catalytic support (alphaAl2O3) on the dissociation of H2O and the surface diffusion of oxygen and hydrogen species along the alphaAl2O3 surface. Our results indicate that upon interaction with the surface, water spontaneously dissociates, forming hydroxyls with unsaturated surface Al and neighboring oxygen atoms. In addition, we find that oxygen species can easily diffuse locally but there is a large barrier to long range surface diffusion in the absence of defects or other species. In contrast, the barrier to the long range surface diffusion of hydrogen is modest under ideal conditions.
Identification of paxilin domains interacting with β-catenin

Barrier-protective agonists induce association of focal adhesions (FA) and adherens junctions (AJ) in endothelial cells. Here we identified specific domains of FA protein paxillin interacting with AJ protein and examined regulation of paxillin domain interactions with β-catenin by Rac GTPase. Co-expression of paxillin LD-1,2; LD-3,4; LIM-1,2; and LIM-3,4 domains with β-catenin showed exclusive interaction of LIM-1,2 and LIM-3,4 with β-catenin, which was enhanced by agonist-induced Rac activation or expression of activated Rac mutant. These results demonstrate a novel function of paxillin LIM domains in targeting β-catenin in a Rac-dependent manner, which may play a role in Rac-dependent control of FA-AJ interactions and monolayer integrity.
Accurate Determination of Leucine and Valine Side-chain Conformations using U-[15N/13C/2H]/[1H-(methine/methyl)-Leu/Val] Isotope Labeling, NOE Pattern Recognition, and Methine Cγ–Hγ/Cβ–Hβ Residual Dipolar Couplings: Application to the 34-kDa Enzyme IIAChitobiose

An isotope labeling scheme is described in which specific protonation of methine and methyl protons of leucine and valine is obtained on a 15N/13C labeled background with uniform deuteration of all other non-exchangeable protons. The presence of a protonated methine group has little effect on the favorable relaxation properties of the methyl protons of Leu and Val. This labeling scheme permits the rotameric state of leucine side-chains to be readily determined by simple inspection of the pattern of Hγ(i)–HN(i) and Hγ(i)–HN(i+1) NOEs in a 3D 15N-separated NOE spectrum free of complications arising from spectral overlap and spin-diffusion. In addition, one-bond residual dipolar couplings for the methine 13C–1H bond vectors of Leu and Val can be accurately determined from an intensity J-modulated constant-time HCCH-COSY experiment and used to accurately orient the side-chains of Leu and Val. Incorporation of these data into structure refinement improves the accuracy with which the conformations of Leu and Val side-chains can be established. This is important to ensure optimal packing both within the protein core and at intermolecular interfaces. The impact of the method on protein structure determination is illustrated by application to enzyme IIAChitobiose, a 34 kDa homotrimeric phosphotransferase protein.
Centromeric localization of dispersed Pol III genes in fission yeast.

The authors show that Pol III transcribed genes such as tRNA and 5S rRNA genes localize to centromeres in fission yeast. The centromeric localization of Pol III genes is mediated by condensin. This...
Municipal police departments’ attention to crime analysis: essential or impractical?

Technologically advanced strategies such as crime analysis have great potential for impacting a department’s efficiency, crime reduction, and professionalism. Yet, to what extent are they being used or perceived as necessary by police departments. This study examines the use of such strategies in New Jersey police departments in cities with a population of 15,000 and above. Specifically, we surveyed 90 police departments in New Jersey in an effort to determine the type of computer technology they possess, as well as the extent and manner to which they use crime analysis. We found that although most departments use crime analysis, few use modern strategies in such endeavors.