cssi/SciSciGPT-SciSciNet huggingface dataset:
An H/sub infinity /-almost disturbance decoupling problem for nonstrictly proper systems-A singular perturbation approach

The authors consider the almost disturbance decoupling problem with internal stability for a general class of nonstrictly proper systems. Under a set of solvability conditions, the state feedback and the observer-based measurement feedback controllers are explicitly constructed. All the developed controllers guarantee the asymptotic stability of the closed-loop system in the absence of the disturbances. Furthermore, they maintain disturbance quenching in the H/sub infinity / sense. The controllers are parameterized in terms of a tuning parameter through which the desired degree of decoupling can be achieved. >
Interactive Exploration of the AFS File System

Managing file systems of large organizations can present significant challenges in terms of the number of users, shared access to parts of the file system, and securing and monitoring critical parts of the file system. We present an interactive exploratory tool for monitoring and viewing the complex relationships within the Andrews File System (AFS). This tool is targeted as an aid to system administrators to manage users, applications and shared access. We tested our tool on UNC Charlottes Andrews File System (AFS) file system, which contains 4554 users, 556 user groups, and 2.2 million directories. Two types of visualizations are supported to explore file system relationships. In addition, drill-down features are provided to access the user file system and access control information of any directory within the system. All of the views are linked to facilitate easy navigation.
Colocalization of thin-walled dome regions with low hemodynamic wall shear stress in unruptured cerebral aneurysms

Object Wall shear stress (WSS) plays a role in regulating endothelial function and has been suspected in cerebral aneurysm rupture. The aim of this study was to evaluate the spatial relationship between localized thinning of the aneurysm dome and estimated hemodynamic factors, hypothesizing that a low WSS would correlate with aneurysm wall degeneration. Methods Steady-state computational fluid dynamics analysis was performed on 16 aneurysms in 14 patients based on rotational angiographic volumes to derive maps of WSS, its spatial gradient (WSSG), and pressure. Local dome thickness was estimated categorically based on tissue translucency from high-resolution intraoperative microscopy findings. Each computational model was oriented to match the corresponding intraoperative view and numerically sampled in thin and normal adjacent dome regions, with controls at the neck and parent vessel. The pressure differential was computed as the difference between aneurysm dome points and the mean neck pressure. Pulsatil...
Optical Neural Nets

The sections in this article are 1 Fundamentals of Optical Image Processing 2 Spatial Light Modulators 3 Optical Pattern Recognition 4 Optical Neural Computing 5 Multilayer Optical Neural Nets Using Holographic Memory 6 Optical Associative Memory 7 Optical Correlator Associative Memory 8 Hologram-Based Associative Memory 9 Summary
Developmental screening: (still) expecting the impossible?

The widespread popularity of the Denver Developmental Screening Test (DDST) during the past 25 years has been accompanied by considerable scrutiny. Certain criticisms, such as the lack of updated norms, the limited extent to which norms may apply to groups such as disadvantaged children, and the difficulty in administering some items, appear justified.1 However, a number of studies critical of the DDST examine applications beyond the intended purpose of this instrument, such as identifying developmental delay among biologically vulnerable infants, screening for speech and language problems, and identifying children with moderate to severe delays.2 The inaccurate or inappropriate way in which the test has been administered and interpreted has troubled the test9s developers.3
The Hermansky-Pudlak Syndrome: Clinical Features and Imperatives from an Ophthalmic Perspective

The Hermansky-Pudlak Syndrome (HPS) is a rare, autosomal recessive condition comprising nine genetically heterogeneous entities that feature oculocutaneous albinism (OCA) and bleeding tendency as their principal clinical manifestations. The pathogenesis of HPS involves disturbances in the biogenesis and trafficking of lysosome-related organelles. While the ophthalmologist is trained to address the ocular manifestations of OCA, it is critical for the provider to consider HPS when examining OCA patients as its systemic sequelae may be associated with morbidity and mortality. If there is suspicion of HPS in a patient with albinism, the ophthalmologist should enlist the aid of consultants to confirm the diagnosis and monitor for systemic features. As the nine HPS subtypes explored in this article vary widely in the character and severity of their associated systemic manifestations, some authors advocate determining the specific gene defect in each HPS patient in order to optimize care and provide anticipatory guidance.
Home Nasogastric Feeds: Feeding Status and Growth Outcomes in a Pediatric Population

Background: Home enteral nutrition (HEN) is a safe method for providing nutrition to children with chronic diseases. Advantages of HEN include shorter hospitalizations, lower cost, and decreased risk of malnutrition-associated complications. Follow-up after hospital discharge on HEN is limited. The purpose of this study was to look at children discharged on nasogastric (NG) feeds to assess follow-up feeding status and impact on growth. Methods: A retrospective chart review was conducted of pediatric patients discharged from Mount Sinai Medical Center on NG feeds between January 2010 and March 2013. Results: A total of 87 patients were included. Average age was 1.2 years. The most common diagnoses were congenital heart disease (47%), metabolic disease (17%), neurologic impairment (10%), liver disease (9%), prematurity (8%), and inflammatory bowel disease (6%). At most recent follow-up, 44 (50.6%) were on full oral feeds, 8 (9.2%) were still on NG feeds, 9 (10.3%) had a gastrostomy tube placed, 9 (10.3%) we...
Memory T cell subsets in B cell non-Hodgkin's lymphomas.

Memory T cells were quantitated by three color flow cytometry in cell suspensions from biopsy specimens of 34 B cell non-Hodgkin's lymphomas (NHL) and 10 benign lymphoid hyperplasias (BLH). CD3+CD45RO-CD45RA+ (naive), CD3+CD45RO+CDRA- (memory) and total CD3+ T cells were compared in BLH, low grade (LG), intermediate (IG) and high grade (HG) B cell NHL. Mean percentage ± s.e. of CD45RO + T cells for BLH, LG, IG and HG NHL were: 14.7 ± 3.8, 11.2 ± 3.5, 28.9 ± 7.5 and 45 ± 15, respectively. Mean percentage ± s.e. of CD45RA + T cells were: 10.2 ± 2.6, 7.1 ± 2.3, 5.4 ± 1.4 and 3.5 ± 1.2, respectively. Mean percentage ± s.e. of total CD3+ T cells were: 42.5 ± 11, 22.4 ± 7.5, 39.3 ± 10.1 and 62.7 ± 22.2, respectively. Memory and total T cells progressively increased from LG toward IG and HG NHL while naive T cells simultaneously decreased. Although the differences in naive T cells were non-significant, the differences in memory T cells were significant between LG and IG and LG and HG NHL (both p. 0100). We previ...
The chlorine and fluorine contents of geochemical standards

Abstract Chlorine and fluorine analyses are reported for 22 geochemical standards, with a precision of better than 5%. Significant variations in the Cl F ratio of various igneous rock types are noted.
Preliminary biological evaluation of polyamidoamine (PAMAM) StarburstTM dendrimers

PAMAM Starburst™ dendrimers are spherical macromolecules composed of repeating polyamidoamino units. They can be produced in successive “generations,” each with a defined size, molecular weight, and number of terminal amino groups. Because of these well-defined characteristics, PAMAMs are finding utility in a variety of applications, many of which are biological in nature. Little is known, however, about the biological behavior of the PAMAMs, which is critical to their use in vivo. Generation 3 (G3; MW = 5,147; 24 terminal amines), 5 (G5; MW = 21,563; 96 amines), and 7 (G7; MW = 87,227; 384 amines) PAMAMs were studied in V79 cells or in Swiss-Webster, mice for a number of biological properties, including (1) in vitro toxicity, (2) in vivo toxicity, (3) immunogenicity, and (4) biodistribution. Potential biological complications were observed only with G7 at the highest level tested. No evidence of immunogenicity was seen. The biodistribution properties of the Starburst™ dendrimers were rather unusual. G3 showed the highest accumulation in kidney tissue (∼15% ID/g over 48 h); G5 and G7 appeared to preferentially localize in the pancreas (peak levels ∼32% ID/g at 24 h, and ∼20% ID/g at 2 h, respectively). In addition, G7 showed extremely high urinary excretion, with values of 46 and 74% ID/g at 2 and 4 h, respectively. In general, the dendrimers did not exhibit properties that would preclude their use in biological applications. Depending on the situation (desired endpoint, dose, and generation used), however, the biodistribution of biological preparations should be carefully studied. © 1996 John Wiley & Sons, Inc.
Vibrational-rotational analysis of some of the fundamentals of vinylsilane

Abstract The infrared spectrum at a resolution of 0.06 cm−1 has been recorded for vinylsilane. Vibrational-rotational analysis has been carried out on ν6, ν13, ν15, and the strongly coupled pair of ν12 and ν19. The rotational constants and some of the distortion constants have been determined for ν6, ν13, and ν15, whereas higher resolution of 0.004 cm−1 was required to obtain similar data from the coupled pair of ν12 and ν19. These data are compared to the ground state constants previously obtained from the microwave spectrum.
Modern portfolio theory.I

This column returns to the topic of investment engineering. Previous columns on this topic have established the following foundation: a) a block diagram view of investment engineering; b) the lognormal model of price behavior; c) the efficient market approximation; d) the nonideal behavior of real markets. The remainder of the series will present two different approaches to market analysis. One starts from the efficient market approximation and the lognormal price model. It then derives results of practical importance, including modern portfolio theory (MPT) and options pricing theory (OPT). The other starts with the assumption that market sentiment should not be neglected and proceeds to develop the tools of technical analysis (TA). This column provides an introduction to MPT
A computational model for signaling pathways in bounded small-world networks corresponding to brain size

A computational model, the bounded composite inverse-d architecture (BCIA), was developed to characterize signaling in small-world networks with large but bounded numbers of nodes, as in human brains. The model is based upon an N-dimensional symmetrical grid with borders, with complete local connections from each node and relatively fewer long-range connections. The length of the signaling pathway generated by a greedy algorithm between two nodes exhibited polylogarithmic behavior when the grid distance between the nodes was less than m, the maximal length of a long-range connection for that network. The simulated length of signaling pathway became linear with internode distance when the grid distance between the two nodes was greater than m. The intensity of long-range connections among nodes was found to be negatively related to the simulated length of signaling pathway. For a constant grid distance between nodes, the average length of a simulated signaling pathway increased with dimension of the BCIA graph. Most strikingly, BCIA simulations of networks with large but bounded numbers (10^9-10^1^3) of nodes, approximating the number of neurons in the human brain, found that the length of simulated signaling pathway can be substantially shorter than that predicted by the best known asymptotic theoretical bound in small-world networks of infinite size.
Explaining Social Policy Preferences: Evidence from the Great Recession

To what extent do personal circumstances, as compared to ideological dispositions, drive voters’ preferences on welfare policy? Addressing this question is difficult because a person's ideological position can be an outcome of material interest rather than an independent source of preferences. The article deals with this empirical challenge using an original panel study carried out over four years, tracking the labor market experiences and the political attitudes of a national sample of Americans before and after the eruption of the financial crisis. The analysis shows that the personal experience of economic hardship, particularly the loss of a job, had a major effect on increasing support for welfare spending. This effect was appreciably larger among Republicans than among Democrats, a result that was not simply due to a “ceiling effect.” However the large attitudinal shift was short lived, dissipating as individuals’ employment situations improved. The results indicate that the personal experience of an economic shock has a sizable, yet overall transient effect on voters’ social policy preferences.
Plane EHL Problems for Pre-Critical Heavy-Loaded Contact: Stable Numerical Solutions

The paper is aimed at considering the classic isothermal plane EHL problem for heavy-loaded contacts lubricated by Newtonian and non-Newtonian fluids. The analytical analysis of the problem is based on matched asymptotic expansions. For pre-critical lubrication regimes asymptotic equations for pressure and gap are derived and solved numerically in the inlet and exit zones. The number of input parameters in asymptotic equations is reduced. The numerical solutions are stable. Formulas for lubrication film thickness for Newtonian and non-Newtonian fluids for pre- and over-critical regimes are derived based on the asymptotic analysis.Copyright © 2008 by ASME
A Robust Optimization Approach to Capital Rationing and Capital Budgeting

We study the pure capital rationing and the horizon capital budgeting problems using a robust optimization framework. The models and the methodology we propose take into account the uncertainty of the input data. The uncertainty of the cash flows is modeled as a range of values that is allowed for each uncertain data. Unlike stochastic models, this approach does not make assumptions on the probability distribution of uncertain data. Moreover, this approach is highly tractable, easy to implement, and provides insights into portfolio selection problems. An attractive point of the model is that the decision maker can set the value of the parameters that control the robustness of the optimal solution, in order to balance the trade-off between protection level and performance. We illustrate our models with examples that show promising results. We also provide new duality and KKT optimality conditions.
Transient Natural Convection in Enclosures With Application to Solar Thermal Storage Tanks

Many previously studied natural convection enclosure problems in the literature have the bounding walls of the enclosure responsible for driving the flow. A number of relevant applications contains sources within the enclosure which drive the fluid flow and heat transfer. The motivation for this work is found in solar thermal storage tanks with immersed coil heat exchangers. The heat exchangers provide a means to charge and discharge the thermal energy in the tank. The enclosure is cylindrical and well insulated. Initially the interior fluid is isothermal and quiescent. At time zero, a step change in the source temperature begins to influence the flow. The final condition is a quiescent isothermal fluid field at the source temperature. The governing time-dependent Navier-Stokes and energy equations for this configuration are solved by a finite element method. Solutions are obtained for 10[sup 3] [le] Ra[sub D] [le] 10[sup 6]. Scale analysis is used to obtain time duration estimates of three distinct heat transfer regimes. The transient heat transfer during these regimes are compared with limiting cases. In this paper correlations are presented for the three regimes.
Selected Pharmacological Studies of Luffa operculata

An aqueous extract of Luffa operculata Cong. Cucurbitaceae (Cabacinha) was tested in mice for the following pharmacological effects: toxicity, analgesia (“grid shock” method), alteration of neuromuscular coordination (rotarod), and modification of barbiturate metabolism (hexobarbital sleeping time). The extract was evaluated in rats for analgesic effects (heat method); effects on electroshock seizure threshold; effects on blood pressure, pulse, electrocardiographic, and respiratory patterns; and anti-inflammatory activity. It was tested in guinea pigs for protective effect against histamine-induced bronchospasm. The extract was found to be inactive in all except analgesic studies in mice, in which a significant elevation of pain threshold was seen with 160 mg/kg ip. The 24-hr LD50 of the extract in mice was 160 mg/kg ip. A possible mechanism of the action is discussed.
Reply to “Can Bacillus cereus Food Poisoning Cause Sudden Death?”

Hossein Sanaei-Zadeh in the [foregoing letter][1] ([4][2]) has raised some intriguing possibilities to account for the rapid death of a 20-year-old male after eating a meal of leftover spaghetti ([3][3]). The time frame and symptoms were characteristic of Bacillus cereus food poisoning ([2][4]).
Computational simulations of the Trichoderma reesei cellobiohydrolase I acting on microcrystalline cellulose Iβ: the enzyme–substrate complex

Cellobiohydrolases are the dominant components of the commercially relevant Trichoderma reesei cellulase system. Although natural cellulases can totally hydrolyze crystalline cellulose to soluble sugars, the current enzyme loadings and long digestion times required render these enzymes less than cost effective for biomass conversion processes. It is clear that cellobiohydrolases must be improved via protein engineering to reduce processing costs. To better understand cellobiohydrolase function, new simulations have been conducted using CHARMM of cellobiohydrolase I (CBH I) from T. reesei interacting with a model segment (cellodextrin) of a cellulose microfibril in which one chain from the substrate has been placed into the active site tunnel mimicking the hypothesized configuration prior to final substrate docking (i.e., the +1 and +2 sites are unoccupied), which is also the structure following a catalytic bond scission. No tendency was found for the protein to dissociate from or translate along the substrate surface during this initial simulation, nor to align with the direction of the cellulose chains. However, a tendency for the decrystallized cellodextrin to partially re-anneal into the cellulose surface hints that the arbitrary starting configuration selected was not ideal.
Mathematical formulation of Witten's superstring field theory

Abstract The physical and ghost vertex operators in covariant superstring field theory are obtained. The integral and star operations are given in oscillator form and the free and interaction lagrangians are explicitly displayed for the massless fields.
Antifreeze peptide heterogeneity in an antarctic eel pout includes an unusually large major variant comprised of two 7 kDa type III AFPs linked in tandem.

Abstract The structural heterogeneity of the major antifreeze peptides (AFPs) from the antarctic eel pout, Lycodichthys dearborni (formerly classified as Rhigophila dearborni ) was characterized. Three major AFPs designated as RD1, RD2 and RD3, and five minor ones were isolated from the fish plasma. RD1 and RD2 are both 64 residues in length, about 7 kDa, and thus similar in size to all characterized type III AFPs, while RD3 is twice as large, about 14 kDa, and represents the first example of a disparately large size variant within the same fish for the three known types of antifreeze peptides. RD3 was found to be 134 residues in length, arranged as a 64-residue N-terminal half and a 61-residue C-terminal half of similar sequence to each other and to the 7 kDa type III AM, linked by a 9-residue connector of unmatched sequence. RD3 has slightly lower antifreeze activity than its 7 kDa counterparts, with a melting-freezing point difference of about 0.81°C at 10 mg/ml versus 0.95°C and 0.90°C for RD1 and RD2, respectively. RD1 and RD2 are 94% identical in sequence to each other. They are 98% and 94%, respectively identical to N-terminal half of RD3, and 85% and 77%, respectively, identical to C-terminal half of RD3. By sequence comparison, a previously characterized AFP from this fish [1] was identified to be RD2.
Reliability and validity of the addiction severity index with a homeless sample

The Addiction Severity Index (ASI) is an instrument widely used to assess the treatment problems of substance users. Its psychometric properties have been tested and found satisfactory for many types of substance abusers entering treatment. However, there are many other subgroups of substance users not in formal treatment, such as homeless substance users. While the ASI has been used with this subgroup, its psychometric properties remain questionable. This study examined the reliability and validity of the ASI in a sample of 98 homeless substance users awaiting temporary housing placement. Test-retest reliability found the ASI to have moderate to high reliability coefficients in each of the seven domains assessed. Both composite score and severity rating measures were found to be quite independent with low intercorrelations. Three of the seven ASI composite scores were tested for and found to have moderate concurrent validity: alcohol (r = .31 to .36), drug (r = .46), and psychiatric (r = .53 to .66). Composite score interitem correlations were .70 or greater in each of the domains except for employment (.50) and family (.52). These data suggest that, although there are some limitations in using the ASI with homeless substance users, it demonstrated acceptable reliability and validity.
NQO1-activated phenothiazinium redox cyclers for the targeted bioreductive induction of cancer cell apoptosis

Altered redox signaling and regulation in cancer cells represent a chemical vulnerability that can be targeted by selective chemotherapeutic intervention. Here, we demonstrate that 3,7-diaminophenothiazinium-based redox cyclers (PRC) induce selective cancer cell apoptosis by NAD(P)H:quinone oxidoreductase (NQO1)-dependent bioreductive generation of cellular oxidative stress. Using PRC lead compounds including toluidine blue against human metastatic G361 melanoma cells, apoptosis occurred with phosphatidylserine externalization, loss of mitochondrial transmembrane potential, cytochrome c release, caspase-3 activation, and massive ROS production. Consistent with reductive activation and subsequent redox cycling as the mechanism of PRC cytotoxicity, coincubation with catalase achieved cell protection, whereas reductive antioxidants enhanced PRC cytotoxicity. Unexpectedly, human A375 melanoma cells were resistant to PRC-induced apoptosis, and PRC-sensitive G361 cells were protected by preincubation with the NQO1 inhibitor dicoumarol. Indeed, NQO1 specific enzymatic activity was 9-fold higher in G361 than in A375 cells. The critical role of NQO1 in PRC bioactivation and cytotoxicity was confirmed, when NQO1-transfected breast cancer cells (MCF7-DT15) stably overexpressing active NQO1 displayed strongly enhanced PRC sensitivity as compared to vector control-transfected cells with baseline NQO1 activity. Based on the known overexpression of NQO1 in various tumors these findings suggest the feasibility of developing PRC lead compounds into tumor-selective bioreductive chemotherapeutics.
Recall rate of screening ultrasound with automated breast volumetric scanning (ABVS) in women with dense breasts: a first quarter experience.

Abstract Purpose The aim of this study was to determine the recall rate of screening ultrasound with automated breast volumetric scanning (ABVS) in women with dense breasts (BI-RADS density classification 3 or 4 on mammogram). Materials and Methods In this retrospective cohort study, at the end of the “first quarter” (August–October 2013) of use, our practice database was searched for all ABVS examinations performed and specifically, the positive examinations (defined as abnormal/BI-RADS 0) for which patients were recalled for additional imaging evaluation with handheld ultrasound (HHUS); the latter group was reviewed with respect to final BI-RADS and pathology if relevant. Results During the 3-month study time period, 558 ABVS studies were performed: 453 (81%) were initially BI-RADS 1 or 2 and 105 (19%) were BI-RADS 0-incomplete and recalled, corresponding with an overall recall rate of 19%; specifically, the recall rate trended down from 24.7% in August to 12.6% in October. To date, 98 of the 105 recalled women have returned for HHUS, with the resultant final BI-RADS as follows: 25/98=25% BI-RADS 1, 46/98=47% BI-RADS 2, 13/98=13% BI-RADS 3, 14/98=15% BI-RADS 4, and 0/98=0% BI-RADS 5. All biopsies performed to date of the ABVS-detected BI-RADS 4 lesions have yielded benign results, with the most common pathology being fibroadenoma. Conclusion The recall rate of screening ABVS in women with dense breasts at our institution was under 20% overall during its first quarter of use, and trended down from nearly 25% in the first month to under 13% in the third. The clinical implication is that ABVS does have a learning curve, but that is a potentially feasible way to meet the increasing demands for screening ultrasound in women with dense breasts.
Teaching students to think like historians — Great American history machine

TEACHERS OF HISTORY at the undergraduate level have tried various means of inducing students to think “like historians.” The author offers an account of how historians think which stresses the search for patterns in large bodies of evidence to generate, more than to test, hypotheses. He describes a computer application for enabling students to do this through interactive access through a map interface to historical county-level U.S. census data, and a U.S. history course in which this application has been implemented.
Comment on "Spontaneous-emission suppression on arbitrary atomic transitions".

A Comment on the Letter by Jorg Evers and Christop H. Keitel, Phys. Rev. Lett. 89, 163601 (2002). The authors of the Letter offer a Reply.
Abstract 3558: The natural product silvestrol decreases oncogenic FLT3 andmiR-155levels inFLT3-ITD positive Acute Myeloid Leukemia (AML) cells

Despite improvement in our understanding of leukemogenic mechanisms, the majority of AML patients (pts) fail to achieve long-term survival and die of their disease. Therefore, new therapeutic options are needed. Silvestrol, a natural product isolated from Aglaia foveolata, has been shown to have potent antitumor activity, most likely through inhibition of initiation of translation. Promising synergistic effects of silvestrol with chemotherapy were shown in AML, but the exact mechanism mediating the antileukemic activity remains to be fully elucidated. Recently, microRNAs (miRs), short non-coding RNAs, have been recognized to contribute to leukemogenesis by inhibiting expression of targeted tumor suppressor genes. Therefore, we hypothesized that the antileukemic effect of silvestrol may at least be partly mediated by activity on miRs. We investigated the effects of silvestrol on the expression of a panel of miRs previously linked to AML (miR-29a, miR-29b, miR-29c, miR-181a, miR-34a & miR-155) by quantitative RT-PCR in representative AML cell lines (MV4-11, Kasumi-1, K562). Among the miRs measured, miR-155 was the only one found to be altered, with >40% reduction from baseline following 24h silvestrol treatment (50nM). MiR-155 has a known oncogenic effect in leukemia and is up-regulated in FLT3-ITD (internal tandem duplication)-positive blasts. FLT3 encodes a tyrosine kinase membrane receptor, and the FLT3-ITD mutation is carried by ∼30% of all AML pts. FLT3-ITD supports abnormal myeloid blast proliferation and survival, and predicts dismal outcome. Silvestrol treatment of FLT3-ITD-positive MV4-11 cells resulted in a sustained 40% decrease of miR-155 expression observed as early as 6h post-treatment, as well as down-regulation (80%) of FLT3 mRNA and protein expression compared with vehicle-treated controls as measured by quantitative RT-PCR and immunoblotting respectively. We confirmed this finding by demonstrating a significant reduction of FLT3 surface expression by flow cytometry. These effects were associated with a significant antiproliferative and apoptotic activity of silvestrol on MV4-11 cells (IC 50 Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3558.
Stress triggering in thrust and subduction earthquakes and stress interaction between the southern San Andreas and nearby thrust and strike-slip faults

[1] We argue that key features of thrust earthquake triggering, inhibition, and clustering can be explained by Coulomb stress changes, which we illustrate by a suite of representative models and by detailed examples. Whereas slip on surface-cutting thrust faults drops the stress in most of the adjacent crust, slip on blind thrust faults increases the stress on some nearby zones, particularly above the source fault. Blind thrusts can thus trigger slip on secondary faults at shallow depth and typically produce broadly distributed aftershocks. Short thrust ruptures are particularly efficient at triggering earthquakes of similar size on adjacent thrust faults. We calculate that during a progressive thrust sequence in central California the 1983 Mw = 6.7 Coalinga earthquake brought the subsequent 1983 Mw = 6.0 Nunez and 1985 Mw = 6.0 Kettleman Hills ruptures 10 bars and 1 bar closer to Coulomb failure. The idealized stress change calculations also reconcile the distribution of seismicity accompanying large subduction events, in agreement with findings of prior investigations. Subduction zone ruptures are calculated to promote normal faulting events in the outer rise and to promote thrust-faulting events on the periphery of the seismic rupture and its downdip extension. These features are evident in aftershocks of the 1957 Mw = 9.1 Aleutian and other large subduction earthquakes. We further examine stress changes on the rupture surface imparted by the 1960 Mw = 9.5 and 1995 Mw = 8.1 Chile earthquakes, for which detailed slip models are available. Calculated Coulomb stress increases of 2–20 bars correspond closely to sites of aftershocks and postseismic slip, whereas aftershocks are absent where the stress drops by more than 10 bars. We also argue that slip on major strike-slip systems modulates the stress acting on nearby thrust and strike-slip faults. We calculate that the 1857 Mw = 7.9 Fort Tejon earthquake on the San Andreas fault and subsequent interseismic slip brought the Coalinga fault ∼1 bar closer to failure but inhibited failure elsewhere on the Coast Ranges thrust faults. The 1857 earthquake also promoted failure on the White Wolf reverse fault by 8 bars, which ruptured in the 1952 Mw = 7.3 Kern County shock but inhibited slip on the left-lateral Garlock fault, which has not ruptured since 1857. We thus contend that stress transfer exerts a control on the seismicity of thrust faults across a broad spectrum of spatial and temporal scales.
Structure of Turbulent Reacting Gas Jets Submerged in Liquid Metals

Abstract A model for predicting the turbulent, multiphase, diffusion-flame structure of a gaseous oxidizer jet submerged in a molten-metal fuel is described. Axisymmetric flow was considered using the locally homogeneous flow approximation of multiphase flow in conjunction with a well-calibrated k-e-g model of turbulence properties. Effects of buoyancy were considered in the governing equations for mean properties. The model was evaluated using existing data for vertical chlorine jets submerged in dilute-Na/NaCl molten baths at atmospheric pressure. Combustion products for these reactants are condensible; therefore, the portion of the flow containing gas has a finite penetration length—somewhat analogous to flame lengths in gaseous single-phase diffusion flames. Predicted and measured penetration lengths and mean temperatures along the jet axis were in fair agreement using conventional turbulence model constants established for single-phase flows. The predictions indicate a complex flow structure containi...
Monitoring time-dependent volcanic dynamics at Long Valley Caldera using InSAR and GPS measurements

Continuous monitoring Long Valley Caldera since the late 1970s, including data from seismic and geodetic networks has shown renewed episodic unrest activities with accelerated uplift separated by reduced uplift, no activity or slow deflation. We examine the time-dependent behaviors at Long Valley Caldera in 1996–2009 by integrating InSAR and continuous GPS (CGPS) measurements. The ERS-1/2 radar data between 1992 and 2008 and reprocessed three-component continuous GPS (CGPS) data from Long Valley GPS network in 1996–2009 were combined to invert for source geometry and volume change in the following deformation episodes: 97–98 uplift, 02–03 uplift, 04–07 slow subsidence, and 07–09 slow uplift. Our results show that all post-2000 events locate in the shallow depth range of ∼7–9 km and have nearly identical source location, suggesting that these events are caused by the same partial melt magma source at the mid-crustal level. All three events are characterized by the low volume change, in comparison with previous 1997–1998 inflation event that has much larger volume change and steeper source geometry. If we regard post-2000 events as proxy for future eruption hazard, the inferred source dynamics (e.g., mid-crustal location and low volume change) from these post-2000 events suggest that the probability for near-term eruption is low. Our study demonstrates that CGPS, along with InSAR, are important tools in monitoring time-dependent source process at the active volcano region.
Adsorption of short-chain organic acids onto nearshore marine sediments

Abstract The adsorption of acetate, butyrate, lactate, and stearate was measured using a clastic mud from Cape Lookout Bight N.C. (CLB), a lateritic muddy sand from Kahana Stream, Oahu, Hawaii (KS), and a fine carbonate sand from Waimanalo Beach, Oahu, (WB). Partition coefficients (Kd, moles adsorbed per g of solid phase/moles dissolved per ml of porewater) ranged from 102.3 to ≤10−3.0, and displayed the following trends: CLB > KS > WB, and stearate > acetate ∼- butyrate > lactate. The percent adsorption of the sediment organic acid pools showed similar trends: stearate, 99%; acetate, 9–23%; butyrate, 5–23%; lactate, ≤0.2–7%. These results reflected the relatively nonpolar nature of the sand surfaces in WB and KS sediments, and the polarities of the organic acids. Kd was approximately constant for each organic acid-sediment combination over a dissolved organic acid concentration range of 107, using concentrations between 1M and 10−14 M. This constancy over a wide porewater concentration range suggested that adsorption was not limited by the availability of surface adsorption sites.
Microinstruments and microsensors for space science

Abstract Advances in micromachining technology in many defense and civilian programs make it feasible to design miniature sensors and instruments of the order of 10 2 –10 3 and 10 3 –10 4 g, respectively. By applying new signal detection principles, we have designed microspectrometers, microseismometers, microsamplers and other devices, which are now in varying phases of development and testing. Microspacecraft of the order of 10 kg, employing miniature sensors and instruments, are uniquely suited for three types of space science missions: missions that require multiple simultaneous measurements in different locations, missions that require very high launch energy and high risk missions where risk may be reduced by replacing a single large and expensive spacecraft with numerous independent small crafts. Applications examined include seismological and meteorological measurements on planetary surfaces and atmospheres and investigation of the mesoscale plasma structure around the Earth.
Prey mortality profiles indicate that Early Pleistocene Homo at Olduvai was an ambush predator

Abstract The prime-adult-dominated mortality profile of large bovids in the 1.8 Ma FLK Zinj assemblage, Olduvai Gorge, Tanzania, was recently attributed to ambush hunting by early Homo (Bunn, H.T., Pickering, T.R. 2010. Quat. Res. 74, 395–404). We now investigate a logical follow-up question: is enough known about the causes and pervasiveness of prime-adult-dominated mortality profiles (defined as >70% prime adults) from modern ecosystems and from archaeological sites to warrant their attribution solely to hominin hunting? Besides hominin hunting, three methods of scavenging could have provided the large bovids butchered at FLK Zinj: first-access scavenging from non-predator-related accidents; late-access passive scavenging from lion (or other) kills; early-access aggressive scavenging from lion (or other) kills. We present new data on hunted prey from Hadza bow hunting (e.g., N = 50 impala; N = 18 greater kudu) near Lake Eyasi, Tanzania, and from San bow hunting (N = 13 gemsbok) in the Kalahari Desert, Botswana, documenting non-selective, living-structure profiles. We present new data on drowned wildebeest (N = 175) from Lake Masek, in the Serengeti, documenting many prime adults but also a significantly high percentage of old adults, unlike the profile at FLK Zinj. We also examine mortality profiles from modern African lions and from Old World Pleistocene archaeological sites, revealing that while prime-dominated profiles are present in some archaeological assemblages, particularly some Late Pleistocene European sites involving cervids, they are not documented from lion or other larger carnivore predation; moreover, living-structure profiles with prime adults representing ∼50–60% of prey are common, particularly in African archaeological assemblages involving bovids hunted by humans. Although taphonomic bias, prey socioecology, and season of death may all influence mortality profiles, prime-dominated profiles require careful evaluation. The prime-dominated profile at FLK Zinj is significantly different from profiles formed by the three scavenging methods, which likely indicates hunting by Early Pleistocene Homo.
A study of enhancive parameter correction with coupled data assimilation for climate estimation and prediction using a simple coupled model

Uncertainties in physical parameters of coupled models are an important source of model bias and adversely impact initialisation for climate prediction. Data assimilation using error covariances derived from model dynamics to extract observational information provides a promising approach to optimise parameter values so as to reduce such bias. However, effective parameter estimation in a coupled model is usually difficult because the error covariance between a parameter and the model state tends to be noisy due to multiple sources of model uncertainties. Using a simple coupled model consisting of the 3-variable Lorenz model and a slowly varying slab ‘ocean’, this study first investigated how to enhance the signal-to-noise ratio in covariances between model states and parameters, and then designed a data assimilation scheme for enhancive parameter correction (DAEPC). In DAEPC, parameter estimation is facilitated after state estimation reaches a ‘quasiequilibrium’ where the uncertainty of coupled model states is sufficiently constrained by observations so that the covariance between a parameter and the model state is signal dominant. The observation-updated parameters are applied to improving the next cycle of state estimation and the refined covariance of parameter and model state further improves parameter correction. Performing dynamically adaptive state and parameter estimations with speedy convergence, DAEPC provides a systematic way to estimate the whole array of coupled model parameters using observations, and produces more accurate state estimates. Forecast experiments show that the DAEPC initialisation with observation-estimated parameters greatly improves the model predictability - while valid ‘atmospheric’ forecasts are extended two times longer, the ‘oceanic’ predictability is almost tripled. The simple model results here provide some insights for improving climate estimation and prediction with a coupled general circulation model. Keywords: Coupled model bias; climate drift; parameter optimization; coupled data assimilation (Published: 1 January 2012) Citation: Tellus A 2012, 64 , 10963, DOI: 10.3402/tellusa.v64i0.10963
Kinetics of ethylene combustion in the synthesis of vinyl acetate over a Pd/SiO2 catalyst

Abstract The kinetic parameters of ethylene combustion in the presence of acetic acid, i.e., during the synthesis of vinyl acetate and in the absence of acetic acid, have been measured in the temperature range 413–453 K over Pd supported on a high surface area SiO2 (600 m2/g) at pressures ranging from 5.0 to 15.0 kPa of C2H4 and 1.0 to 10.0 kPa of O2. CO2 formation as a function of the partial pressures of C2H4 and O2 exhibited a negative reaction order with respect to C2H4 and a positive order with respect to O2. The kinetic parameters of ethylene combustion in the presence and absence of acetic acid were essentially the same, consistent with ethylene combustion being primarily responsible for CO2 formation in the synthesis of vinyl acetate from ethylene and acetic acid over unpromoted Pd within the pressure regime investigated.
The relative roles of the glutathione redox cycle and catalase in the detoxification of H2O2 by cultured rabbit lens epithelial cells

The relative roles of the glutathione redox cycle and catalase in the detoxification of H2O2 were investigated in cultured rabbit lens epithelial cells. Exposure of cells to H2O2 was carried out following inhibition of either of the two antioxidant systems. Two different procedures were used to expose the cells to extracellular H2O2, one in which a low, steady state level of 0.025 mM H2O2 was maintained in the culture medium with the use of glucose oxidase and the other in which H2O2 was added to the medium as a single pulse at levels ranging from 0.03 to 0.5 mM. When lens cells were treated with a low, steady state level of H2O2, the glutathione redox cycle was the primary means of defense against oxidative damage. Cells with fully active catalase but with inhibited glutathione reductase were not able to resist the cytotoxic effects of a 0.025 mM level of extracellular H2O2. Under these conditions the cells were nearly completely depleted of reduced glutathione within 15 min. The cellular damage observed after 1.5 hr of culture included loss of cell-to-cell contact, rounding up of the cells and formation of numerous blebs. In contrast, cells with completely inhibited catalase but with an unimpaired glutathione redox cycle suffered few damaging effects from a 3-hr exposure to 0.025 mM H2O2. When lens cells were pulsed with a single challenge of 0.5 mM H2O2, both the glutathione redox cycle and catalase were found to be essential for survival of the cells. While control cells were able to withstand the pulse of H2O2, cells with impaired activities of either the glutathione redox cycle or catalase were killed. Control cells treated with 0.5 mM H2O2 may have been protected from damage by the fact that the cellular level of GSH never dropped below 35% of normal. The cause of cell death following inhibition of catalase appeared to be related to an inability of the cells to remove peroxide from the culture medium, at a rapid rate, following the H2O2-pulse. Although cells with impaired glutathione reductase activity removed H2O2 from the medium at a rate comparable to that of control cells (due to uninhibited catalase activity), they did not survive the challenge.(ABSTRACT TRUNCATED AT 250 WORDS)
Experimental Study of the Flowfield of a Two-Dimensional Premixed Turbulent Flame

A turbulent reacting shear layer in a premixed propane/air flow has been studied in a two-dimensional combustor, with a flame stabilized behind a rearward facing streamlined step. Spark shadowgraphs show that in the range of velocities (7.5-22.5 m/s corresponding to Reynolds numbers of 0.5xl0 4-1.5xl04 cm"1) and equivalence ratios (0.4-0.7) studied, the mixing layer is dominated by Brown-Roshko type large coherent structures in both reacting and nonreacting flows. High-speed schlieren movies show that these eddies are convected downstream and increase their size and spacing by combustion and coalescence with neighboring eddies. Tracing individual eddies shows that on average eddies accelerate in the reacting shear layer as they move downstream, with the highest acceleration close to the origin of the shear layer. Combustion is confined to those large structures which develop as a result of vortical action of the shear flow. On the average, the reacting eddies have a lower growth rate than nonreacting eddies. A turbulent boundary layer created by means of a tripping wire upstream of the edge of the step virtually eliminates the large coherent structures in the shear layer, while for the case in which the wire could not trigger the transition to turbulence, the large coherent structures dominated the reacting and nonreacting flows.
Vortex-state complex Hall conductivity of superconducting YBa 2 Cu 3 O 7 − δ epitaxial films at radio frequencies

The first intermediate-frequency measurements of the vortex-state complex Hall conductivity \sigma_xy of YBa_2CU_3O_7 superconducting epitaxial films are reported. A direct transport measurement technique from dc to 7 MHz was used. The results are analyzed in terms of a phenomenological model, generalized from that for the dc Hall conductivity, with the assumptions that: 1) the sign reversal in the vortex-state Hall conductivity is associated with the different carrier densities within and far away from the vortex cores; 2) the Drude approximation Is applicable; and 3) the anomalous sign reversal occurs in the flux-flow Limit. The temperature, frequency, and magnetic field (B) dependencies of our \sigma_xy data are in good agreement with the model. The B-dependence of \sigma_xy reveals that both vortices (\sigma_xyAv \propto BA-1) and quasiparticles (sigma_xyAq \propto B) contribute to the vortex-state Hall conduction. The magnitude of the real part of \sigma_xy, \sigma_xyA\prime, is in good agreement with our model, while that of the imaginary part, \sigma_xyA\prime \prime, is significantly Luger than the theoretical prediction. This may be attributed to the unconventional electronic structures in the vortex core of cuprate superconductors with d-wave or mixed pairing symmetries.
Entrance meniscus in a pressurized optical fiber coating applicator

Abstract The present work describes experimental measurements relevant to the coating process of optical fibers in pressurized applicators. The focus was on the entrance geometry, which was simulated using micropipettes of different sizes allowing visualization of the free surface with apparatus operating off-line, using glycerol as the surrogate coating liquid. The meniscus shape and position were measured for different applicator pressures, fiber speeds and tube diameters, and conditions for air entrapment were identified.