cssi/SciSciGPT-SciSciNet huggingface dataset:
Laser ignition of bulk 1018 carbon steel in pure oxygen

Experiments were undertaken to study the ignition characteristics of bulk 1018 carbon steel in a pure oxygen environment. Cylindrical 1018 carbon steel specimens 5 mm in diameter and 5 mm high were ignited by a focused CW CO2 laser beam in a cool, static, pure oxygen environment at oxygen pressures ranging from 0.103 to 6.895 MPa. A two-color pyrometer was designed and used to measure the ignition temperatures of the specimens. The temperature history of a spot approximately 0.5 mm in diameter located at the center of the specimen top surface was recorded with a maximum time resolution of 25 microsec, and with an accuracy of a few percent. Ignition temperature of bulk 1018 carbon steel was identified from the temperature history curve with the aid of the light intensity curve. Results show that 1018 carbon steel specimens ignite at temperatures between 1388 and 1450 K, which are below the melting range of the alloy (1662-1685 K). The ignition temperature of 1018 carbon steel is mildly dependent on oxygen pressure over the range of oxygen pressure investigated in this study.
Causes of Death and Conditional Survival Estimates of Medium- and Long-term Survivors of Pancreatic Adenocarcinoma

This population-based study investigates the survival and causes of death in patients with pancreatic adenocarcinoma to 21 years after diagnosis.
Student’s t-Test for Matched Pairs

The purpose of this lesson is to use R to examine differences to a singular measured variable between pairs, specifically by using Student’s t-Test for Matched Pairs. Along with the use of Student’s t-Test to compare differences between two separate groups against a singular measured variable, Student’s t-Test can also be used to compare differences to a single measured variable when subjects are matched against a counterpart. This lesson also provides an introduction to the use of unstacked data as compared to the use of stacked data. Finally, the issues of sample size (especially N of 30 or so) and sample representation are introduced in this lesson.
Enzymatic Synthesis of Acetono-CoA, A Competitive Inhibitor of Acetyl-CoA with Citrate Synthase

The synthetic acetyl-CoA analog, acetono-CoA (acetonyldethiocoenzyme A), in which the sulfur atom has been replaced by a methylene group, has been previously synthesized and found to be a competitive inhibitor (KI= 13.2 µM) of acetyl-CoA with citrate synthase. To determine whether the acetono-group would interfere with CoA biosynthesis, a crude preparation of the bifunctional enzyme complex which converts ATP and pantetheine 4’-phosphate to CoA was investigated. Incubation mixtures of the crude complex, ATP, and acetonyldethio-pantetheine 4’-phosphate were prepared. Products and reactants were isolated by DEAE-cellulose column chromatography and peaks were identified by TLC. Enzymatic synthesis of acetono-CoA was verified by establishing its KI (25 µM) in the citrate synthase reaction.
Rapid diagnosis of acute promyelocytic leukemia by immunohistochemical localization of PML/RAR-alpha protein

Acute promyelocytic leukemia (APL) is characterized by a consistent chromosomal aberration that fuses the retinoic acid receptor alpha (RAR alpha) gene with the novel gene PML, resulting in the expression of a PML/RAR-alpha fusion protein. Immunohistochemical examination of APL cells shows a unique abnormal distribution of anti-PML and anti-RAR alpha antibody labeling. The PML labeling pattern observed in normal cells consists of 5 to 10 discrete spherical nuclear bodies called PODs (for “PML oncogenic domains”), whereas that of APL consists of a smaller and far more numerous speckled pattern. We examined malignant cells from patients with a variety of hematopoietic cancers by immunohistochemistry (IH) and found this abnormal PML pattern expressed in cells from patients with t(15;17)-associated leukemia but not in patients with other neoplastic disorders. IH results agreed with reverse transcription polymerase chain reaction for PML/RAR-alpha in 31 of 32 patients with acute myelogenous leukemia, including 5 of 5 patients in whom the initial clinical diagnosis of APL was not supported by cytogenetics, molecular tests, or response to all-trans retinoic acid (RA). Cells from patients with APL were examined during the course of retinoid therapy and at the time of complete remission and relapse. Reorganization of the PML labeling into PODs with normal appearance was observed in cells from patients who received RA. IH showed primarily normal PML staining during clinical remission, although the APL-specific labeling pattern was again seen in cells taken from patients at the time of relapse. Thus, IH provides an independent assay for the presence and expression of the molecular rearrangement of APL. The relative ease and speed of detecting the APL- specific PML labeling pattern should make IH a useful diagnostic tool to guide specific therapy of APL, and establish a direct assay for PML/RAR-alpha protein expression and localization in individual patient cells.
The effects of scale: How Western agency-anxieties mold affect theory, and how Pentecostalism and neuroscience teach us to think differently:

This paper offers a critique of affect theory using the analytical concept of scale that is made concrete through an ethnography of Pentecostal Christianity and an exploration of current neuroscien...
Exemplar-based knowledge acquisition

Exemplar-Based Knowledge Acquisition is an excellent reference document describing a promising knowledge acquisition tool, the Protos system. Since it is publicly available, Protos provides a testbed for a variety of techniques and issues in machine learning: (1) the integration of similarity-based and explanation-based approaches, (2) the transition from user guidance to autonomy, and (3) the relation between knowledge representation and efficiency. Much work remains to be done to assess Protos' scaleability and to uncover and repair any possible existing complexity problems.
Fire regime characteristics in relation to physiography at local and landscape scales in Lake States pine forests

Abstract Examining fire regime characteristics across temporal and spatial scales is critical to understanding relationships between fire and landscape physiography. In the Lake States (Wisconsin, Michigan, Minnesota) we have often relied on either broad extrapolation from local studies, and/or interpretations of coarse-scale Euro settlement era records tied to landscape-scale physiography to understand complex fire regimes. In this study, we used detailed fire frequency and origin-to-first-scar (OFS, patterns of fire-scar formation) intervals to evaluate fire characteristics in relation to physiography at local and landscape scales. We found frequent fires (mean fire return intervals, MFRI = 8 years) and widespread fire years were common among our sites. OFS intervals were also less than half as long (µ = 18.3) as intervals often deemed necessary for seedlings to survive fires (ca. 50 years). We found no differences in either MFRI or OFS intervals nor physiographic effects (topography and water features) at broad ecological landscape scales. Most variability in OFS was accounted for at a site scale with increased water features and topographical ruggedness both resulting in shorter OFS intervals (trees surviving and recording fires at a younger age). We found few differences in MFRI’s among sites, which ranged from 4 to 13 years. Relationships between fire resistance and stand level physiography, which was highly variable, may have a greater role than recognized in forest successional stages and stand dynamics.
Personal exposure to polycyclic aromatic hydrocarbons in Appalachian mining communities

Abstract Coal mining activities may increase residential exposure to polycyclic aromatic hydrocarbons (PAHs), but personal PAH exposures have not been studied in mining areas. We used silicone wristbands as passive personal samplers to estimate PAH exposures in coal mining communities in Central Appalachia in the United States. Adults (N = 101) wore wristbands for one week; 51 resided in communities within approximately three miles of surface mining sites, and 50 resided 10 or more miles from mining sites. Passive indoor polyurethane foam (PUF) sampling was conducted in residents’ homes, and a sample of 16 outdoor PUF samples were also collected. Nine PAH congeners were commonly detected in wristbands (mean ± standard deviation), including phenanthrene (50.2 ± 68.7 ng/g), benz[a]anthracene (20.2 ± 58.2 ng/g), fluoranthene (19.4 ± 24.1 ng/g) and pyrene (15.2 ± 18.2 ng/g). Controlling for participant characteristics and season, participants living closer to mining sites had significantly higher levels of phenanthrene, fluorene, fluoranthene, pyrene and ∑PAHs in wristbands compared to participants living farther from mining. Indoor air showed no significant group differences except for pyrene, but outdoor air showed significant or marginally significant differences for phenanthrene, fluorene, pyrene and ∑PAHs. The results suggest that mining community residents face exposure to outdoor mining-related pollutants, and demonstrate that personal silicone wristbands can be deployed as effective passive sampling devices.
Single-cell mass cytometry reveals cross-talk between inflammation-dampening and inflammation-amplifying cells in osteoarthritic cartilage

Aging or injury leads to degradation of the cartilage matrix and the development of osteoarthritis (OA). Because of a paucity of single-cell studies of OA cartilage, little is known about the interpatient variability in its cellular composition and, more importantly, about the cell subpopulations that drive the disease. Here, we profiled healthy and OA cartilage samples using mass cytometry to establish a single-cell atlas, revealing distinct chondrocyte progenitor and inflammation-modulating subpopulations. These rare populations include an inflammation-amplifying (Inf-A) population, marked by interleukin-1 receptor 1 and tumor necrosis factor receptor II, whose inhibition decreased inflammation, and an inflammation-dampening (Inf-D) population, marked by CD24, which is resistant to inflammation. We devised a pharmacological strategy targeting Inf-A and Inf-D cells that significantly decreased inflammation in OA chondrocytes. Using our atlas, we stratified patients with OA in three groups that are distinguished by the relative proportions of inflammatory to regenerative cells, making it possible to devise precision therapeutic approaches.
Implications of Clonal Hematopoiesis for Precision Oncology

Clonal hematopoiesis (CH) is common in middle-aged and elderly populations and confers a risk of hematological malignancy and also death due to cardiovascular disease. Prior therapy with cytotoxic ...
Life's Simple 7 cardiovascular health score and premature atrial contractions: The atherosclerosis risk in communities (ARIC) study

Abstract Background Premature atrial contractions (PACs) are associated with increased risk of atrial fibrillation (AF) and ischemic stroke. Although lifestyle and risk factor modification reduces AF incidence, their relationship to PACs frequency is unclear. We assessed the association of Life's Simple 7 (LS7) and individual LS7 factors in midlife with PACs frequency in late life in the Atherosclerosis Risk in Communities (ARIC) Study. Methods We followed 1924 participants from ARIC clinic Visit 3 (1993‐–95) to Visit 6 (2016–17) when a 2-week continuous heart rhythm monitor (Zio®XT Patch) was applied. LS7 factors were assessed at Visit 3 and a composite score was calculated. PACs frequency was categorized as minimal ( ≥ 0.1%–5%) and frequent (>5%). Logistic regression was used to evaluate the association of LS7 score and individual factors with PACs frequency. Results Each 1-point LS7 score increase was associated with lower odds of frequent PACs vs. no PACs (OR [95% CI]: 0.87 [0.78, 0.98]) and frequent PACs vs. occasional PACs (OR [95% CI]: 0.88 [0.79, 0.98]). Of the individual LS7 factors, compared with ideal physical activity, poor physical activity was associated with 81% higher odds of frequent PACs vs. no PACs. Compared with ideal BMI, poor BMI was associated with 41% higher odds of occasional PACs vs. no PACs. Conclusion Lifestyle risk factors, particularly physical activity and BMI, are associated with higher odds of PACs frequency. More research is needed to determine whether modifying these risk factors in midlife would prevent frequent PACs, and thereby prevent AF and stroke in older age.
Oxidant-resistant LRRC8A/C anion channels support superoxide production by NADPH oxidase 1.

KEY POINTS LRRC8A-containing anion channels associate with NADPH oxidase 1 (Nox1) and regulate superoxide production and tumour necrosis factor-α (TNFα) signalling. Here we show that LRRC8C and 8D also co-immunoprecipitate with Nox1 in vascular smooth muscle cells. LRRC8C knockdown inhibited TNFα-induced O2•- production, receptor endocytosis, nuclear factor-κB (NF-κB) activation and proliferation while LRRC8D knockdown enhanced NF-κB activation. Significant changes in LRRC8 isoform expression in human atherosclerosis and psoriasis suggest compensation for increased inflammation. The oxidant chloramine-T (ChlorT, 1 mM) weakly (∼25%) inhibited LRRC8C currents but potently (∼80%) inhibited LRRC8D currents. Substitution of the extracellular loop (EL1, EL2) domains of 8D into 8C conferred significantly stronger (69%) ChlorT-dependent inhibition. ChlorT exposure impaired subsequent current block by DCPIB, which occurs through interaction with EL1, further implicating external oxidation sites. LRRC8A/C channels most effectively sustain Nox1 activity at the plasma membrane. This may result from their ability to remain active in an oxidized microenvironment. ABSTRACT Tumour necrosis factor-α (TNFα) activates NADPH oxidase 1 (Nox1) in vascular smooth muscle cells (VSMCs), producing superoxide (O2•- ) required for subsequent signalling. LRRC8 family proteins A-E comprise volume-regulated anion channels (VRACs). The required subunit LRRC8A physically associates with Nox1, and VRAC activity is required for Nox activity and the inflammatory response to TNFα. VRAC currents are modulated by oxidants, suggesting that channel oxidant sensitivity and proximity to Nox1 may play a physiologically relevant role. In VSMCs, LRRC8C knockdown (siRNA) recapitulated the effects of siLRRC8A, inhibiting TNFα-induced extracellular and endosomal O2•- production, receptor endocytosis, nuclear factor-κB (NF-κB) activation and proliferation. In contrast, siLRRC8D potentiated NF-κB activation. Nox1 co-immunoprecipitated with 8C and 8D, and colocalized with 8D at the plasma membrane and in vesicles. We compared VRAC currents mediated by homomeric and heteromeric LRRC8C and LRRC8D channels expressed in HEK293 cells. The oxidant chloramine T (ChlorT, 1 mM) weakly inhibited 8C, but potently inhibited 8D currents. ChlorT exposure also impaired subsequent current block by the VRAC blocker DCPIB, implicating external sites of oxidation. Substitution of the 8D extracellular loop domains (EL1, EL2) into 8C conferred significantly stronger ChlorT-mediated inhibition of 8C currents. Our results suggest that LRRC8A/C channel activity can be effectively maintained in the oxidized microenvironment expected to result from Nox1 activation at the plasma membrane. Increased ratios of 8D:8C expression may potentially depress inflammatory responses to TNFα. LRRC8A/C channel downregulation represents a novel strategy to reduce TNFα-induced inflammation.
Design and evaluation of an open-source, conformable skin-cooling system for body magnetic resonance guided focused ultrasound treatments.

Magnetic resonance guided focused ultrasound (MRgFUS) treatment of tumors uses inter-sonication delays to allow heat to dissipate from the skin and other near-field tissues. Despite inter-sonicatio...
Gut microbiome composition and serum metabolome profile among individuals with spinal cord injury and normal glucose tolerance or prediabetes/type 2 diabetes

Abstract Objective To compare the gut microbiome composition and serum metabolome profile among individuals with spinal cord injury (SCI) and normal glucose tolerance (NGT) or prediabetes/type 2 diabetes (preDM/T2D). Design Cross-sectional design. Setting Research university. Participants A total of 25 adults (N=25) with SCI were included in the analysis and categorized as NGT (n=16) or preDM/T2D (n=9) based on their glucose concentration at minute 120 during a 75-g oral glucose tolerance test. The American Diabetes Association diagnosis guideline was used for grouping participants. Interventions Not applicable. Main Outcome Measures A stool sample was collected and used to assess the gut microbiome composition (alpha and beta diversity, microbial abundance) via the 16s ribosomal RNA sequencing technique. A fasting serum sample was used for liquid chromatography–mass spectrometry–based untargeted metabolomics analysis, the results from which reflect the relative quantity of metabolites detected and identified. Gut microbiome and metabolomics data were analyzed by the Quantitative Insights into Microbial Ecology 2 and Metaboanalyst platforms, respectively. Results Gut microbiome alpha diversity (Pielou's evenness index, Shannon's index) and beta diversity (weighted UniFrac distances) differed between groups. Compared with participants with NGT, participants with preDM/T2D had less evenness in microbial communities. In particular, those with preDM/T2D had a lower abundance of the Clostridiales order and higher abundance of the Akkermansia genus, as well as higher serum levels of gut-derived metabolites, including indoxyl sulfate and phenylacetylglutamine (P Conclusions Our results provide evidence for altered gut microbiome composition and dysregulation of gut-derived metabolites in participants with SCI and preDM/T2D. Both indoxyl sulfate and phenylacetylglutamine have been implicated in the development of cardiovascular diseases in the able-bodied population. These findings may inform future investigations in the field of SCI and cardiometabolic health.
Insider Trading, Earnings Quality, and Accrual Mispricing

This paper investigates whether insider trading is informative about earnings quality and the valuation implications of accruals. We show that (1) the one‐year‐ahead persistence of income‐increasing accruals is significantly lower when accompanied by abnormal insider selling and greater when accompanied by abnormal insider buying; (2) the accrual mispricing phenomenon observed in previous work (e.g., Sloan 1996) is due to the mispricing of income‐increasing accruals; (3) one‐year‐ahead hedge returns to trading strategies based on the direction of accruals and insider trading significantly exceed those based on accruals alone; and (4) the lower persistence of income‐increasing accruals accompanied by abnormal insider selling appears to be at least partly attributable to opportunistic earnings management. Our evidence suggests that market participants and researchers can use managers' contemporaneous trading in ex ante assessing the likelihood that the firms' accruals are of high or low quality, and in asse...
Introduction to Atmospheric Chemistry

Preface 1. Evolution of the Earth's atmosphere 2. Half-life, residence time and renewal time of chemicals in the atmosphere 3. Present chemical composition of the atmosphere 4. Interactions of solar and terrestrial radiation with atmospheric trace gases and aerosols 5. Sources, transformations, transport, and sinks of chemicals in the troposphere 6. Atmospheric aerosols 7. Cloud and precipitation chemistry 8. Tropospheric chemical cycles 9. Air pollution 10. Stratospheric chemistry Appendices Index.
A dual component heme biosensor that integrates heme transport and synthesis in bacteria

Bacterial pathogens acquire host iron to power cellular processes and replication. Heme, an iron-containing cofactor bound to hemoglobin, is scavenged by bacterial proteins to attain iron. Methods to measure intracellular heme are laborious, involve complex chemistry, or require radioactivity. Such drawbacks limit the study of the mechanistic steps of heme transport and breakdown. Hypothesizing heme homeostasis could be measured with fluorescent methods, we coupled the conversion of heme to biliverdin IXα (a product of heme catabolism) by heme oxygenase 1 (HO1) with the production of near-infrared light upon binding this verdin by infrared fluorescent protein (IFP1.4). The resultant heme sensor, IFP-HO1, was fluorescent in pathogenic E. coli exposed to heme but not in the absence of the heme transporter ChuA and membrane coupling protein TonB, thereby validating their long-standing proposed role in heme uptake. Fluorescence was abolished in a strain lacking hemE, the central gene in the heme biosynthetic pathway, but stimulated by iron, signifying the sensor reports on intracellular heme production. Finally, an invasive strain of E. coli harboring the sensor was fluorescent during an active infection. This work will allow researchers to expand the molecular toolbox used to study heme and iron acquisition in culture and during infection.
Direct frequency comb spectroscopy

We summarize recent developments in direct frequency-comb spectroscopy that allowed high-resolution, broad-bandwidth measurements of multiple atomic and molecular resonances using only a phase-stabilized femtosecond laser, opening the way for merging precision spectroscopy with coherent control.
Prolactin-induced regression of the rat corpus luteum: expression of monocyte chemoattractant protein-1 and invasion of macrophages.

Monocyte chemoattractant protein-1 (MCP-1) is a potential mediator of the recruitment of monocytes/macrophages into the regressing corpus luteum (CL). We investigated whether the luteolytic effect of prolactin in the rat is associated with the expression of MCP-1 and an invasion of monocytes/macrophages. Ovulation was induced in immature female rats by injection of eCG (5 IU, s.c.) at 30 days of age. All rats were hypophysectomized 3 days later. Rats received injections of ovine prolactin (250 micrograms, s.c.) at 12-h intervals on Day 9, 10, and 11 posthypophysectomy; controls received injection of vehicle. Rats were killed by decapitation 24, 48, or 72 h after the first injection of prolactin or vehicle. In rats treated with prolactin, immunoreactive MCP-1 was detected in the CL at 24 h after the first injection, and a consistent level of staining was reached by 72 h with immunodetectable MCP-1 diffused throughout individual CL. The number of monocytes/macrophages in the CL (mean +/- SEM) increased significantly after prolactin treatment, from 3.1 +/- 1.8 at 24 h to 49.3 +/- 8.2 at 72 h (p < 0.05), and the number of monocytes/macrophages was different from that in control, vehicle-treated rats at 72 h (10.3 +/- 4.1; p < 24 and 72 h in prolactin-treated rats (p < 0.05). It is concluded that a potentially important component of the luteolytic effect of prolactin in the rat is the expression of MCP-1 and invasion of monocytes/macrophages into the CL.
Alpha-emitting nuclides in the marine environment

Abstract The occurrence of alpha-emitting nuclides and their daughter products in the marine environment continues to be a subject of study for many reasons. Those nuclides which occur naturally, in the uranium, thorium and actinium series, are of interest because of their value in determining the rates of geological and geochemical processes in the oceans. Studies of them address such problems as the determination of rates of transfer of particulate matter, deposition rates, bioturbation rates, and so on. Two of the natural alpha-series nuclides in which a different interest has been expressed are 210Po and 226Ra, because their concentrations in marine organisms are such that they contribute to a significant fraction of the background dose rates sustained both by the organisms themselves and by consumers of marine fish and shellfish. To this pool of naturally-occurring nuclides, human activities have added the transuranium nuclides, both from the atmospheric testing of nuclear devices and from the authorized discharges of radioactive wastes into coastal waters and the deep sea. Studies have therefore been made to understand the chemistry of these radionuclides in sea water, their association with sedimentary materials, and their accumulation by marine organisms, the last of these being of particular interest because the transuranics are essentially “novel” elements to the marine fauna and flora. The need to predict the long-term behaviour of these nuclides has, in turn, stimulated research on those naturally-occurring nuclides which may behave in a similar manner.
The use of approval plans by large academic libraries in times of fiscal stringency: A brief report

A summary is given of the results of a questionnaire sent to each of the academic library members of the Association of Research Libraries. The results were used to up-date research on approval plans and to analyse the effects of budgetary problems upon the use of these automatic purchase plans.
Magnetic Energy Release during the 2002 September 9 Solar Flare

We study the magnetic energy release during the 2002 September 9 flare using the high-cadence (40 ms) Hα filtergram at Big Bear Solar Observatory (BBSO), along with hard X-ray and microwave data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) and the Owens Valley Solar Array (OVSA), respectively. We take the Poynting vector approach with the standard two-dimensional geometry of the reconnecting current sheet (RCS) but suggest a new technique to infer the area of the RCS, in order to complete the magnetic energy calculation entirely with observed quantities. We found five peaks of impulsive magnetic energy release, concentrated within 10-30 s periods, that are episodic with the peaks of the hard X-ray light curve. The maximum amount of energy released per peak reaches ~2.6 × 1030 ergs s-1, and the electron energy deposition rate derived from the RHESSI spectra falls into the range of 10%-80% of the magnetic energy release rate. We briefly discuss this result in comparison with other studies thus far made toward understanding of the magnetic reconnection in solar flares and suggest the pulsating current sheet model as the most plausible interpretation of our result.
Boson-like expansions without bosons: Application to several exactly soluble shell models with collective features

Abstract It is recognized that the generators of a Lie algebra can be divided into three sets {Y † , Y, Z} . The set Y † acting on a reference state generates a basis, Y generating the dual basis; it follows that any Z can be expressed as a polynomial in the Y † and Y . Examples of such expansions for the algebra SU(2) and R(5), as well as for the algebras of more realistic shell model problems are presented. These expansions play an essential role in approximate and successful algebraic studies of two exactly soluble models: the SU(2) model of Meshkov, Glick, and Lipkin and an R(5) symmetric model of vibrations and rotations in a plane devised by the authors.
Geometric measure of entanglement and applications to bipartite and multipartite quantum states

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings [A. Shimony, Ann. NY. Acad. Sci. 755, 675 (1995); H. Barnum and N. Linden, J. Phys. A: Math. Gen. 34, 6787 (2001)], is explored for bipartite and multipartite pure and mixed states. The measure is determined analytically for arbitrary two-qubit mixed states and for generalized Werner and isotropic states, and is also applied to certain multipartite mixed states. In particular, a detailed analysis is given for arbitrary mixtures of three-qubit Greenberger-Horne-Zeilinger, W, and inverted-W states. Along the way, we point out connections of the geometric measure of entanglement with entanglement witnesses and with the Hartree approximation method.
4-(4-Nitrobenzyl)pyridine tests for alkylating agents following chemical oxidative activation

A chemical activation system (CAS) designed to mimic the mammalian mixed-function oxidase enzymes was found to activate target compounds to reactive electrophiles. Activated compounds were assayed by reaction with 4-(4-nitrobenzyl)pyridine (NBP). A model nucleophile of 7-alkylguanine of nucleic acids, NBP produces a violet color following alkylation. Twenty compounds from several chemical classes were tested. The test generally gave positive and negative responses where expected. Two compounds, trichloroethylene and diethylnitrosamine, exhibited a linear Beer's law relationship in the concentration range tested. A high degree of linear correlation (r>0.97) was obtained for these compounds. Other compounds showed varying degrees of linear correlation from high correlation (r=0.94) to weak correlation (r=0.44). The CAS-NBP assay results were compared to bacterial mutagenicity and animal carcinogenicity test results when information was available. A good correlation (r=0.80) existed between direct alkylating activity and direct mutagenicity. Similar correlations existed between NBP alkylation following activation and mutagenicity following microsomal activation (r=0.73). Also, different correlations were observed between carcinogenicity and NBP alkylation following activation (r=0.69) and without activation (r=0.38).
On culture and the state: The writings of Ngugi wa Thiong'o

(1989). On culture and the state: The writings of Ngugi wa Thiong'o. Third World Quarterly: Vol. 11, No. 1, pp. 148-156.
Optical properties of multicomponent nanometer dimension metal colloids formed in silica by sequential ion implantation of In and Ag and In and Cu

A series of nanometer dimension colloids in silica have been fabricated by sequential implantation of Ag and In, and a series by sequential implantation of In and Cu. Energies of implantation were chosen using TRIM 89 to overlay the depth distributions of the sequentially implanted ions. The implanted layers were characterized using Rutherford backscattering spectroscopy, transmission electron microscopy, and optical spectroscopy. Nanometer dimension metal multicomponent colloids were formed. The depth distribution, particle size, and optical response of the composites were found to depend strongly on the ion species implanted and the relative ratio of the ion species. The optical responses are correlated with composition of the multicomponent nanoclusters.
Maintenance of arytenoid abduction following carbon dioxide laser debridement of the articular cartilage and joint capsule of the cricoarytenoid joint combined with prosthetic laryngoplasty in horses: An in vivo and in vitro study

The objective was to evaluate CO2 laser debridement of the cricoarytenoid joint (CAJ) combined with prosthetic laryngoplasty to prevent post-operative loss of arytenoid abduction in seven horses. Horses were assigned to either laser debridement of the left CAJ and laryngoplasty (laser treated, n=5) or control laryngoplasty (sham, n=2), and were evaluated with endoscopic examinations and measurement of right to left angle quotients (RLQ) to assess maintenance of arytenoid abduction. The animals were euthanased at intervals after surgery and larynges were harvested for post-mortem testing, including determination of translaryngeal flow, pressure, impedance and RLQ. Measurements were obtained under increasing vacuum-generated negative pressure with laryngoplasty sutures intact and with the knot/crimp of the laryngoplasty sutures removed. Following post-mortem testing the cricoarytenoid joints were examined histologically. Post-operative endoscopic examinations revealed no significant differences between RLQ measurements calculated for day 1 following surgery to the termination date of the study for the seven horses. Post-mortem RLQ at airflows of 10 and 60 L/s was significantly higher in sham than in laser treated horses both before and after knot/crimp removal. Translaryngeal impedance at 10 and 60 L/s was not statistically different between groups. Histopathology revealed necrosis and loss of articular cartilage in the laser treated horses. The lymphoid cell infiltration subsided but joint capsule and periarticular fibrosis increased over the course of the study. Post-operative loss of arytenoid abduction after laryngoplasty can be minimized with CO2 laser debridement of the CAJ joint.
Extraction of underlying multiplicative processes from multifractals via the thermodynamic formalism

This paper describes various procedures for extracting an underlying multiplicative process from the thermodynamic description of multifractals (i.e., its ${D}_{q}$ curve), and points out the associated pitfalls of such procedures. We extend previous work by Feigenbaum, Jensen, and Procaccia [Phys. Rev. Lett. 57, 1567 (1986)] using transfer matrices to the case of singular measures, and develop the corresponding thermodynamic formalism. We find that the extraction procedure based solely on information from the ${D}_{q}$ curves allows for an infinity of cascade processes and that additional dynamical information is required to remove this degeneracy. In addition, we find that different multiplicative processes with only three free parameters produce excellent fits to all the ${D}_{q}$ curves studied in this paper, which further confuses the inversion process when it is applied to experimental data. We then examine the application of these procedures to a variety of computer and laboratory experiments, such as the period-doubling attractor, the golden-mean circle-map attractor, and a reanalysis of Rayleigh-B\'enard experiments corresponding to these examples. Finally we consider laboratory experiments on open flows in two different circumstances. The first deals with velocity measurements in the wake of an oscillating cylinder and has dynamics closely related to that of the circle map. The second case corresponds to the spatial distribution of turbulent energy dissipation in several flows (grid turbulence, wakes, and boundary layers in the laboratory and atmosphere), where the underlying dynamics are presently not well understood. In each of these examples we highlight the above-mentioned ambiguities and, in cases where additional information is available, apply the procedure to extract basic underlying length scales of the phenomena.
Are Distance Laboratories Effective Tools for Technology Education

The ability to perform a laboratory experiment as a nonhands-on observer, such as in a distance education context, has been questioned by some educators who ponder whether distance education lab courses are as effective as those held in a physical laboratory environment. This article examines this issue and compares the performance of distance education students with their on-campus counterparts in a junior laboratory course. Data from six semesters are examined and presented. A regression model is developed to predict the performance of both distance education and on-campus students. Results of the model show that only report grades and location (whether distance education or on-campus) are statistically significant. In addition, statistical analysis of the six semesters of data shows equal performance of the two groups.
Impact of wavelet types on image data characteristics during compression

ABSTRACT We examine the effects of wavelet compression on target det ection algorithms when the targets are single-pixel point sources modulated by the point-spread of an optical system. The experimental data combines frames collected from a multispectral sensor with simulated targets based on an Airy function. We studied several different types of wavelets and found that the Daubechies 2 wavelet resulted in the best overall target detection and fewest false alarms with increasing compression. Results show that wavelet compressi on may decrease pixel intensities, increase target signal-to-noise ratio, and reduce false detections. Consequently it may negatively affect target detection unless the detector is designed to take the decrea sed intensity into account. Keywords: Wavelets, compression, target detection, remote se nsing, space-based sensors, target characteristics 1. INTRODUCTION Wavelet analysis is a popular and well-developed an alytical tool, with widesp read use in both signal and image processing. Compression is one of th e many applications of wavelet processing, and wavelet-based methods are used in a number of compression algor ithms, such as JPEG2000 [1]. A great deal of work has been done to understand the effect of wavelet compression on the visual interpretation, but we will focus on a different app lication. We are interested in automatic target detection from remotely sensed data, where the targets are generally sing le-pixel point sources modulated by the optics of the se nsing system. For these applic ations, wavelet compression has a number of desirable properties, part icularly its ability to preserve sharp transient features better than other compression techniques, but it may also introdu ce false alarms or distort the shape of real targets. This study examines the effects of several wavelets on data of this type. Results show that compression with an appropriate wavelet can incr ease signal-to-noise ratio and decrease false alarms, but may adversely affect probability of detection if the level of compression significantly reduces peak intensities. 2. WAVELET COMPRESSION Wavelets (from the French ondelette , small wave) are wave forms with compact support and a net sum of zero. Wavelet analysis uses scaling and translation of wavele t functions to construct a basis set for a signal, capturing information that is lo calized in both space and frequency. The output of a discrete wavelet transform is actually the combina tion of high and low-pass filters applied to the image, providing an approximation (the low pa ss component) and details (the high frequency components) describing the image. In multiresol ution analysis, the approximation values are themselves recursively filtered, cr eating a series of approximation a nd detail coefficients capturing the structure of the image at different scales [2]. The process can be reversed to reconstruct the original image from the coefficients. Performed in this way, the discrete wavelet transform is lossless, but does not actually reduce the size of the data.
A 73-year-old woman with chronic nonhealing cellulitis.

She has undergone extensive treatment with antibiotics and corticosteroids, without success. What is the likely diagnosis?
Performance issues in a real-time true color data display

We discuss the integration of visualization and supercomputing in a low cost environment. Computational requirements continue to increase dramatically as computational capabilities do. Yet most architectures still separate both processes. The computation is done on one system and the visualization on another. We describe an innovative architecture developed by the Supercomputer Research Center of the Institute for Defense Analysis within which the integration of visualization and supercomputation is realized. Immediate gains are obvious: program visualization, real-time computational steering, and rapid porting of current applications. We describe the issues in porting our experimental visualization software and issues we encountered. We describe limitations and advantages of the hardware/software coupling. We also discuss a proposed extension of that architecture.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Natural solutions to the problem of functional integration

Current EEG research emphasizes gamma band coherence as a signature of functional integration, that is, the solution to the binding problem. We note that spatial patterns of coherent neural activity are also observed at other EEG frequencies. If these oscillations reflect Nunez's resonant modes, they offer a solution to the binding problem that emerges naturally from the architecture of cortical connections.
Stressful Life Events and Perimenstrual Symptoms

Abstract The purpose of this study was to determine whether the effects of stressful life events on perimenstrual symptoms were due to operational confounding of the instruments used to measure the independent and dependent variables. Women aged 18 to 35 (n = 179) completed the Schedule of Recent Events (SRE) and the Moos Menstrual Distress Questionnaire during a home interview. When variance in PMS scores attributable to age, parity, education, and contraceptive method was controlled using hierarchical multiple regression, total SRE scores were correlated with premenstrual and menstrual negative affect, menstrual water retention, and menstrual performance impairment. When health-related components of the SRE score were controlled in a similar manner, however, the residual SRE scores explain a diminished amount of the variance in premenstrual and menstrual negative affect and menstrual performance impairment. Future investigations are needed to clarify whether the effects of health-related life events on ...
Long-period orbits in the Stark spectrum of lithium.

We report observation of the signature of very-long-period orbits in the Stark spectrum of lithium in a regime of classical chaos. We identify recurrences associated with the orbits parallel to the electric field, including those beyond the 100th return of the primitive orbit. We also identify recurrences due to scattering of an incoming wave from one orbit into another by the alkali-metal core.
From DNA to Diversity, Molecular Genetics and the Evolution of Animal Design. 2001

Sean B. Carroll, Jennifer K. Greiner, and Scott D. Weatherbee. From DNA to Diversity, Molecular Genetics and the Evolution of Animal Design. 2001. Blackwell Science, Malden, Massachusetts, 214 + xv p. From DNA to Diversity serves as an Evo Devo Intro for Paleo—an accessible, accelerated introduction to the field of developmental biology. The typical paleontologist today did not learn the concept of Hox genes in his or her undergraduate introductory biology course (let alone a campy vocabulary of hedgehogs, zinc fingers, gurkens, and knirps). In their book Carroll, Griener, and Weatherbee review the exciting rejuvenation that evolutionary biology has experienced in the past decade. This colorfully illustrated book provides easy access to the fundamentals of rapidly changing components of evolutionary biology, genetics, and development. This is especially welcome to a paleontologist who wishes to expand his or her knowledge of the field without delving into the depths of the primary literature. The subject matter flows from an introductory overview of the diversity and fundamental divisions of life, through a history of genetics, the chronology of which naturally moves from simple to more complex concepts. A key success of the book for communicating to nonspecialists is in the figures, which are presented in a manner somewhere between a cartoon and a technical drawing. This style is not only helpful in creating a perception of accessibility (i.e., inviting), but the figures are invaluable for the information that they convey in support of the text. The …
Locating the vanguard in rising and falling homicide rates across U.S. cities

This research examines trends in U.S. homicide rates at the city level during the so-called homicide epidemic in the latter decades of the 20th century. Using spline regression techniques to locate structural breaks in city-level time series, we model the true trends of homicide rates to identify those cities that exhibited a meaningful boom and bust cycle. We then use Tobit regressions for all cities at risk of experiencing a cycle to estimate unbiased effects of theoretically important predictors on the timing of the phase changes. Our findings reveal that larger cities were more likely to experience an epidemic-like pattern, and that densely populated cities characterized by high levels of deprivation tended to exhibit the rise and fall in homicide rates earlier than other cities.
Continued caregiver burden: Seizure-free may not equal burden-free

While caregiver burden has been studied in various patient populations, it has not been addressed in caregivers of patients with epilepsy. This study investigated the incidence of perceived caregiver burden in caregivers of patients following surgical treatment for epilepsy, usually temporal lobectomy. The extent to which caregiver and patient variables were related to burden was explored. Data were collected on caregiver depression, caregiver coping skills, the caregiver's evaluation of the patient's functioning, demographic information, and the patient's seizure control for 34 caregiver-patient dyads. The occurrence of significant burden in this population was comparable with the literature for other populations; however, the frequency of item endorsement varied. Regression analysis suggests that depression and patient functioning, separate from seizure control, predicted caregiver burden. The use of emotion-focused coping styles predicted depression. There were no differences in the levels of burden or depression in caregivers over time. Additional research is required to evaluate whether these relationships reflect presurgical functioning or an adjustment to the postsurgical state. Aspects of patient functioning that are important in caregiver burden also need to be clarified. This research may lead to the development of intervention strategies designed to prevent or reduce caregiver burden.
Salmonella-based tumor-targeted cancer therapy: Tumor amplified protein expression therapy (TAPET™) for diagnostic imaging

Abstract In preclinical studies, genetically engineered Salmonella have the ability to localize, selectively accumulate, and persist within transplantable murine tumors, spontaneous murine tumors and human tumor xenographs, and can express therapeutic proteins at high levels. These strains of engineered non-virulent Salmonella typhimurium display the capacity to accumulate and grow selectively in a variety of tumor types and to inhibit the growth of primary and metastatic tumors following intravenous injection into tumor-bearing mice. One strain of the bacteria (VNP20009) which has endogenous antitumor activity is currently in Phase I clinical trials. The bacteria are highly attenuated and genetically stable. The combination of the lipid mutation and the purine auxotrophy attenuate the virulence of the bacteria by greater than 10 000-fold and enhance the specificity of the bacteria for tumor tissue. These bacteria have been found to be safe in mice, pigs and monkeys when administered intravenously. Second-generation Salmonella vectors will be developed to include transgenes that will express therapeutic agents and reporter transgenes for non-invasive imaging. We have performed a preliminary study to demonstrate localization of [ 14 C]FIAU in tumored mice pretreated with Salmonella expressing HSV1-TK. The [ 14 C]FIAU radioactivity and bacterial count data strongly support a Salmonella TK -dependent [ 14 C]FIAU accumulation of at least 30-fold higher in tumor tissue compared to muscle tissue. These data warrant further investigation on the use of genetically engineered Salmonella as a systemically administered tumor-specific agents for tumor therapy and delivery of diagnostic imaging markers.