cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of aging and hyperoxia on oxidative damage to cytochrome c in the housefly, Musca domestica.

Abstract Cytochrome c is a component of the mitochondrial electron transport chain, where it transfers electrons from ubiquinol-cytochrome c reductase to cytochrome c oxidase. Autoxidation of some of the components of the electron transport chain is the main source of intracellular O2−•/H2O2 production in aerobic organisms. Because cytochrome c is located on the outer surface of the inner mitochondrial membrane, it is likely to be constantly exposed to H2O2, secreted by mitochondria into the cytosol. The specific objective of this study was to determine whether cytochrome c in the flight muscle mitochondria of the housefly is oxidatively damaged during aging and/or under severe oxidative stress induced by exposure of flies to 100% oxygen. Results of two independent methods, namely tritiated borohydride labeling for determining carbonylation and mass spectral analysis for the measurement of molecular mass, indicated that neither the carbonyl level nor the molecular mass of cytochrome c was affected by aging or hyperoxia. Thus, either cytochrome c is resistant to oxidative damage in vivo or the oxidized cytochrome c is promptly degraded. These findings also support the concept that protein oxidative damage during aging and under oxidative stress is selective.
Computer augmented teacher training

A new teacher education program has been inaugurated at the University of Massachusetts' School of Education under the title "Computer Augmented Teacher Training". The CATT program places the computer in a central role--particularly the activity of programming--in order to augment the cognitive, affective, and social competencies of prospective mathematics teachers. In the cognitive domain, teachers learn what mathematics to teach as well as how to teach it effectively. In the affective domain, teachers enhance their self-concepts and build self-confidence by encountering both successes and failures in working with manipulative materials, self-instructional texts, and computer-related activities. Finally, in the social area, teachers raise their consciousness about the advantages and limitations of technology as they develop computer literacy.
Particle phenomenology on noncommutative spacetime

We introduce particle phenomenology on the noncommutative spacetime called the Groenewold-Moyal plane. The length scale of spacetime noncommutativity is constrained from the $CPT$ violation measurements in the ${K}^{0}\ensuremath{-}{\overline{K}}^{0}$ system and $g\ensuremath{-}2$ difference of ${\ensuremath{\mu}}^{+}\ensuremath{-}{\ensuremath{\mu}}^{\ensuremath{-}}$. The ${K}^{0}\ensuremath{-}{\overline{K}}^{0}$ system provides an upper bound on the length scale of spacetime noncommutativity of the order of ${10}^{\ensuremath{-}32}\text{ }\text{ }\mathrm{m}$, corresponding to a lower energy bound $E$ of the order of $E\ensuremath{\gtrsim}{10}^{16}\text{ }\text{ }\mathrm{GeV}$. The $g\ensuremath{-}2$ difference of ${\ensuremath{\mu}}^{+}\ensuremath{-}{\ensuremath{\mu}}^{\ensuremath{-}}$ constrains the noncommutativity length scale to be of the order of ${10}^{\ensuremath{-}20}\text{ }\text{ }\mathrm{m}$, corresponding to a lower energy bound $E$ of the order of $E\ensuremath{\gtrsim}{10}^{3}\text{ }\text{ }\mathrm{GeV}$. We also present the phenomenology of the electromagnetic interaction of electrons and nucleons at the tree level on the noncommutative spacetime. We show that the distributions of charge and magnetization of nucleons are affected by spacetime noncommutativity. The analytic properties of electromagnetic form factors are also changed and it may give rise to interesting experimental signals.
Ascites induced in mice by Staphylococcus.

Ascitic fluid containing high titers of antibody was induced in mice by Staphylococcus. Two to three intraperitoneal inoculations of 0.3 ml of a killed suspension of S. aureus mixed with complete Freund9s adjuvant, given at 5-day intervals, produced ascites in 100 percent of the mice tested.
42K efflux, EKG and tension in isolated perfused hearts of white-footed mice.

Abstract 1. 1. The EKG and systolic tension of isolated, perfused hearts from Peromyscus leucopus is a function of the perfusion temperature. 2. 2. The marked loss of 42 K during perfusion at lower temperatures indicates a loss of intracellular potassium and suggests a breakdown in the ability to maintain electrolyte balance. 3. 3. The decline in EKG potential and tension as well as the increased 42 K efflux which occur at perfusion temperatures similar to the lower range of body temperature during torpidity of the intact animal indicate that cardiac performance may limit the depth and length of torpor in P. leucopus .
An inexpensive active optical remote sensing instrument for assessing aerosol distributions.

Air quality studies on a broad variety of topics from health impacts to source/sink analyses, require information on the distributions of atmospheric aerosols over both altitude and time. An inexpensive, simple to implement, ground-based optical remote sensing technique has been developed to assess aerosol distributions. The technique, called CLidar (Charge Coupled Device Camera Light Detection and Ranging), provides aerosol altitude profiles over time. In the CLidar technique a relatively low-power laser transmits light vertically into the atmosphere. The transmitted laser light scatters off of air molecules, clouds, and aerosols. The entire beam from ground to zenith is imaged using a CCD camera and wide-angle (100 degree) optics which are a few hundred meters from the laser. The CLidar technique is optimized for low altitude (boundary layer and lower troposphere) measurements where most aerosols are found and where many other profiling techniques face difficulties. Currently the technique is limited to...
Psychohistory: Clio on the couch - or off?

(1982). Psychohistory: Clio on the couch—or off? Historical Methods: A Journal of Quantitative and Interdisciplinary History: Vol. 15, No. 2, pp. 83-90.
ELISA methods for the analysis of antibody responses induced in multiple sclerosis patients treated with recombinant interferon-β

Upon treatment with protein therapeutics, a subset of patients will typically develop antibodies against the drug. These anti-drug antibodies can be of concern because they have the potential to alter the drug's therapeutic activity. In the case of relapsing-remitting multiple sclerosis (RRMS) patients receiving recombinant interferon-beta (IFN-beta), those receiving BETASERON (IFN-beta-1b; E. coli expressed, non-glycosylated, des-Met-1, Cys17Ser recombinant IFN-beta) have a higher incidence of IFN-beta specific antibodies compared to those receiving AVONEX (IFN-beta-1a; mammalian cell-expressed, natural sequence, glycosylated recombinant IFN-beta). The current study reports the development and characterization of ELISAs that detect distinct components of the anti-IFN-beta response in patients' sera, and therefore can potentially be used to characterize the composition of the anti-IFN-beta antibody response. ELISAs were developed using a constant detecting reagent but a variety of IFN-beta-derived test antigens (e.g., native IFN-beta, biotinylated IFN-beta, IFN-beta peptides) and capture methods. Assays were characterized using serum samples from a small number of patients treated with recombinant IFN-beta (either BETASERON or AVONEX). Assays in which IFN-beta was captured via a specific mAb, or in which biotinylated IFN-beta was captured via streptavidin, detected serum antibodies that recognize IFN-beta in its native structural state. In contrast, assays in which IFN-beta was coated directly onto the assay plates detected antibodies that recognize forms of IFN-beta possessing a folded structure distinct from the native structure. Certain epitopes present on native IFN-beta were not represented in these assays in which the test antigen was directly coated on plastic. Antibodies specific for linear epitopes could be detected using linear peptides as test antigens; the locations of these epitopes were mapped by reference to the X-ray crystal structure of IFN-beta-1a. Together, these data show that the mode of antigen presentation employed in IFN-beta ELISAs determines which antibody specificities are detected, and can affect whether or not a given serum sample is identified as positive for anti-IFN-beta antibodies. As a consequence, screening samples in a single ELISA format presenting IFN-beta in a non-native form may lead to underestimation of the incidence of IFN-beta treated MS patients that have generated antibodies specific to the native, active form of the drug.
A hardware architecture for accelerating neuromorphic vision algorithms

Neuromorphic vision algorithms are biologically inspired algorithms that follow the processing that takes place in the visual cortex. These algorithms have proved to match classical computer vision algorithms in classification performance and even outperformed them in some instances. However, neuromorphic algorithms suffer from high complexity leading to poor execution times when running on general purpose processors, making them less attractive for real-time applications. FPGAs, on the other hand, have become true signal processing platforms due to their lightweight, low power consumption and massive parallel computational resources. This paper describes an FPGA-based hardware architecture that accelerates an object classification cortical model, HMAX. Compared to a CPU implementation, this hardware accelerator offers 23X (89X) speedup when mapped to a single-FPGA (multi-FPGA) platform, while maintaining a classification accuracy of 92.5%.
Characteristics Associated with Preferences for Certain Managerial Positions

The present study was designed to ascertain similarities and differences in personality traits, values, and intellectual abilities between individuals preferring particular kinds of managerial positions. 97 graduate students enrolled in the Graduate School of Management at Vanderbilt expressed their preferences for 10 different organization or job categories: line vs staff, large vs small, ongoing operation vs new venture, produce a product vs provide a service, frequent vs infrequent travel, continual meeting of people vs working with a fixed set of individuals, group settings vs one-on-one situations, close supervision vs being left alone, and working with a large number of people vs working intimately with a few vs working alone. Psychological tests were used to compare individuals having preferences for different managerial positions.
Mechanisms of killing of Bacillus subtilis spores by hypochlorite and chlorine dioxide

Aims: To determine the mechanisms of Bacillus subtilis spore killing by hypochlorite and chlorine dioxide, and its resistance against them. Methods and Results: Spores of B. subtilis treated with hypochlorite or chlorine dioxide did not accumulate damage to their DNA, as spores with or without the two major DNA protective α/β-type small, acid soluble spore proteins exhibited similar sensitivity to these chemicals; these agents also did not cause spore mutagenesis and their efficacy in spore killing was not increased by the absence of a major DNA repair pathway. Spore killing by these two chemicals was greatly increased if spores were first chemically decoated or if spores carried a mutation in a gene encoding a protein essential for assembly of many spore coat proteins. Spores prepared at a higher temperature were also much more resistant to these agents. Neither hypochlorite nor chlorine dioxide treatment caused release of the spore core's large depot of dipicolinic acid (DPA), but hypochlorite- and chlorine dioxide-treated spores much more readily released DPA upon a subsequent normally sub-lethal heat treatment than did untreated spores. Hypochlorite-killed spores could not initiate the germination process with either nutrients or a 1 : 1 chelate of Ca2+-DPA, and these spores could not be recovered by lysozyme treatment. Chlorine dioxide-treated spores also did not germinate with Ca2+-DPA and could not be recovered by lysozyme treatment, but did germinate with nutrients. However, while germinated chlorine dioxide-killed spores released DPA and degraded their peptidoglycan cortex, they did not initiate metabolism and many of these germinated spores were dead as determined by a viability stain that discriminates live cells from dead ones on the basis of their permeability properties. Conclusions: Hypochlorite and chlorine dioxide do not kill B. subtilis spores by DNA damage, and a major factor in spore resistance to these agents appears to be the spore coat. Spore killing by hypochlorite appears to render spores defective in germination, possibly because of severe damage to the spore's inner membrane. While chlorine dioxide-killed spores can undergo the initial steps in spore germination, these germinated spores can go no further in this process probably because of some type of membrane damage. Significance and Impact of the Study: These results provide information on the mechanisms of the killing of bacterial spores by hypochlorite and chlorine dioxide.
Inspiratory and expiratory high-resolution CT findings in a patient with Sjogren's syndrome and cystic lung disease

R ecent studies have emphasized the use of inspiratory and expiratory high-resolution CT in detecting and characterizing small airways disease and concomitant air trapping [I]. It has been suggested that. in some cases, dynamic expiratory highresolution CT may be more sensitive than spirometry in revealing early bronchiolitis [I]. Because Sjogren’s syndrome is a systemic autoimmune exocrinopathy that frequently involves the lungs, pulmonary manifestations include pneumonia, atelectasis, bronchiectasis, interstitial pulmonary disease. lymphoproliferative disorders, and airflow obstruction [2, 3]. Unusual concomitant diseases include amyloidosis and sarcoidosis [4-7]. This case report describes the use of dynamic high-resolution CT in revealing a rare manifestation of Sjogren’s syndrome: bronchiolitis associated with cystic lung disease.
Scanning Tunneling Microscopy Study of a Vicinal Anatase TiO2 Surface

Using scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED), the structure of the anatase TiO2 (514) surface, ∼10° vicinal to the lowest-energy (101) plane, has been studied. The surface was found to facet into a structure composed of ridges with a uniform width of five lattice units. On the basis of atomically resolved STM and electron counting rules, it is proposed that the sides of the ridges are parallel to (110) and (112) planes. These sides might be reconstructed to stabilize the microfaceted structure. Vapor-deposited gold shows pronounced clustering between the ridges, indicating a one-dimensional template effect of the vicinal surface, which supports denser and more uniformly sized Au clusters, as compared to the flat (101) surface.
The vocalsearch music search engine

The VocalSearch system is a music search engine developed at Northwestern University and available on the internet (vocalsearch.org). This system lets the user query for the desired song in a number of ways: sung queries, queries entered as music notation, and text-based lyrics search. Users are also able to contribute songs to the system, making them searchable for future users. The result is a flexible system that lets the user find the song using their preferred modality (music notation, text, music notation). This demonstration lets users try out the VocalSearch system.
Targeting acetylcholinesterase to the neuromuscular synapse

The collagen-tailed form of acetylcholinesterase (ColQ-AChE) is the major if not unique form of the enzyme associated with the specialized synaptic basal lamina at the neuromuscular junction (NMJ). This enzyme form consists of both catalytic and non-catalytic subunits encoded by separate genes, assembled as three enzymatic tetramers attached to the three-stranded collagen-like tail. We have previously shown that catalytic subunits are assembled in the rough endoplasmic reticulum and that after approximately 90 min a subset of these tetramers assemble with collagenic tail subunits in the Golgi apparatus. In muscle, blocking ER to Golgi transport with Brefeldin A prevents the appearance of ColQ-AChE, consistent with assembly of asymmetric forms in the Golgi. Moreover, newly synthesized and assembled ColQ-AChE associates with perlecan intracellularly and can only be co-immunoprecipitated with anti-perlecan antibodies 90 min after the first appearance of catalytic subunits. Once assembled, the ColQ-AChE/perlecan complex is externalized where it co-localizes with other components of the NMJ including dystroglycan, rapsyn, laminin and MuSK. These clusters tend to form over the nuclei that are expressing the components, suggesting local vectorial transport to the cell surface, and may form a primary scaffold that in turn can capture other molecular constituents of the neuromuscular synapse. While most AChE clusters on quail myotubes are devoid of acetylcholine receptors, treatment of the culture with recombinant agrin results in a rapid translocation of receptors to the AChE clusters in less than 4 h. It remains to be determined if MuSK is localized to the clusters. In vivo, AChE transcripts and enzyme are more highly expressed at the NMJs, implying higher rates of AChE translation and assembly in the synaptic regions, and hence more ColQ-AChE for localized export. We have previously shown that binding sites for ColQ-AChE are concentrated at sites of nerve-muscle contact where they colocalize with AChR and perlecan. ColQ-AChE binds directly to perlecan using solid phase microtiter plate assay, the Biacore assay, and co-immunoprecipitations. Moreover, perlecan binds to dystroglycan at the NMJ. In perlecan or dystroglycan null mice there is no accumulation of AChE at the NMJ, supporting the hypothesis that this heparan sulfate proteoglycan is an essential component of the ColQ-AChE localization mechanism. Together, these studies suggest a model of synaptic development whereby AChE can be targeted to and clustered on the muscle membrane together with dystroglycan and perlecan to form scaffolds to which AChR can be clustered through activation of the MuSK receptor. At mature synapses ColQ-AChE is secreted directly into the synaptic cleft where it binds to the heparan sulfate proteoglycan perlecan as well as potentially other molecules including MuSK, as was recently reported.
Evening Activities as a Potential Confound in Research on the Adrenocortical System in Children

The relation among children's evening activities, behavioral characteristics, and activity of the hypothalamic-pituitary-adrenocortical axis was assessed in normally developing children ages 7 to 10 years. Salivary cortisol at bedtime was compared on evenings when children had structured activities outside of the home with unstructured evenings at home in relation to parental reports of children's behavioral characteristics. Participating in evening activities, particularly sport activities, was associated with small increases in bedtime cortisol levels in boys but not in girls. Differences in cortisol on activity versus no-activity nights were negatively related to children's social isolation. These results show that in studies with children, nights on which participants engage in sport activities should be avoided when collecting ambulatory measures of salivary cortisol concentrations.
Benzene metabolites antagonize etoposide-stabilized cleavable complexes of DNA topoisomerase IIα

Chronic exposure to benzene is associated with hematotoxicity and acute myelogenous leukemia. Inhibition of topoisomerase IIα (topo II) has been implicated in the development of benzene-induced cytogenetic aberrations. The purpose of this study was to determine the mechanism of topo II inhibition by benzene metabolites. In a DNA cleavage/relaxation assay, topo II was inhibited by p -benzoquinone and hydroquinone at 10 μM and 10 mM, respectively. On peroxidase activation, inhibition was seen with 4,4′-biphenol, hydroquinone, and catechol at 10 μM, 10 μM, and 30 μM, respectively. But, in no case was cleavable complex stabilization observed and the metabolites appeared to act at an earlier step of the enzyme cycle. In support of this conclusion, several metabolites antagonized etoposide-stabilized cleavable complex formation and inhibited topo II–DNA binding. It is therefore unlikely that benzene-induced acute myelogenous leukemia stems from events invoked for leukemogenic topo II cleavable complex-stabilizing antitumor agents.
Optimized concatenated LDPC codes for joint source-channel coding

In this paper a scheme for joint source-channel coding based on low-density-parity-check (LDPC) codes is investigated. Two concatenated independent LDPC codes are used in the transmitter: one for source coding and the other for channel coding, with a joint belief propagation decoder. The asymptotic behavior is analyzed using EXtrinsic Information Transfer (EXIT) charts and this approximation is corroborated with illustrative experiments. The optimization of the degree distributions for our sparse code to maximize the information transmission rate is also considered.
Total, scattering and γ-ray-production cross sections for few-MeV neutrons on 54Fe

Abstract Cross sections for the following neutron interactions were obtained for 54 Fe in the few-MeV incident-energy range with resolutions of 50–100 keV: total interaction from ∼0.5 to 4 MeV, elastic scattering from 1.2 to 4 MeV, inelastic scattering from 2 to 4 MeV for excitation energies up to 3 MeV, and inelastic-scattering γ-ray production from 1.4 to 3.6 MeV for transitions corresponding to the deexcitation of levels up to 3 MeV. The results are mutually consistent within experimental errors. A spherical optical-statistical model describes the energy-averaged behavior of these experiments reasonably well, although slight evidence for direct-reaction strength is exhibited by the angular distributions of neutrons scattered to the 1.408 MeV, 2 + , level.
EPR of α-MnCl2·4H2O

Abstract A single crystal room temperature X-band electron paramagnetic resonance study of α-MnCl 2 ·4H 2 O revealed an isotropic Lorentzian line with a halfwidth at halfheight of 647 gauss. In addition no temperature variation in the 77–300 K range was observed nor was a frequency variation observed in the 9–14 GHz range. The interpretation indicates that while the exchange field at room temperature is roughly comparable to the low temperature value it is somewhat greater than the EPR observation fields.
Perfluoroalkyl substances and thyroid function in older adults.

Current understanding of the thyroid disruptive properties of perfluoroalkyl substances (PFASs), particularly in aging populations, is limited. The objectives of this study were to (i) assess associations between thyroid function, as measured by serum thyrotropin (thyroid stimulating hormone, TSH), free thyroxine (fT4), total thyroxine (T4), and total triiodothyronine (T3), and serum perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in an aging population and (ii) determine if other persistent organic pollutants with thyroid disruptive properties including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) modify such associations. We conducted a cross-sectional study of 87 men and women 55 to 74 years of age, without clinically-diagnosed thyroid disease, who resided in upper Hudson River communities in New York. Geometric means (standard deviations) of serum PFOS and PFOA were 31.6 (1.7) ng/mL and 9.17 (1.72) ng/mL, respectively. Multivariable linear regression analyses indicated that one interquartile range difference in PFOS corresponded to 4% and 9% increases in fT4 and T4 respectively. We detected statistical interactions between PFOA and age for effects on fT4 and T4; joint increases in PFOA and age were associated with increases in fT4 and T4, of 3% and 7%, respectively. We also detected statistical interactions between PFOS and total PCBs for the effect on T3 and between PFOA and total PBDEs for the effect on TSH. Our results suggest that PFASs are associated with subtle alterations in thyroid hormone levels in this population, and that these associations are likely to vary by age, and levels of PCBs and PBDEs.
Attachment of Fecal Indicator Bacteria to Particles in the Neuse River Estuary, N.C.

Observations of microbial contamination and particle suspensions represent valuable inputs to water quality models that form the basis of regulatory decisions regarding the use of surface waters. The Neuse River Estuary in eastern North Carolina is experiencing a decline in water quality due to increasing anthropogenic inputs. Potentially serious consequences of these inputs are the introduction and persistence of bacterial pathogenic organisms from human and animal waste. A critical factor in determining human health risk is the partitioning of these organisms between particle-attached and free-living cells in the water column. Particle-associated bacteria are generally less mobile in the environment, settle faster, and may have different rates of mortality than their free phase counterparts. Surface and bottom water samples were collected during both dry weather and storm events throughout the summer of 2004 to gage changes in particle concentration, particulate organic carbon and nitrogen, and the part...
Gynandromorphs of Culiseta Inornata (Diptera: Culicidae) Collected by Dry Ice-Baited Cdc Miniature Light Traps

Three bipolar differemiated gynandromorphs of Culiseta inornata were collected by dry ice-baited CDC miniature light traps on Joice Island (Suisun Marsh), Solano County, California, in 1975 and 1976. The morphological characteristics of each were typical of the female for the head and associated appendages and thorax; and male for the tarsal claws, abdomen, and terminalia. Bilateral and mosaic conditions were evident in 2 specimens. The wings of one were bilaterally differentiated right and left into normal male and female types, respectively. The right antenna of the other was intermediate between that of a normal male and normal female.
Regulation of plasma cholesterol esterification by sphingomyelin: Effect of physiological variations of plasma sphingomyelin on lecithin-cholesterol acyltransferase activity

Although sphingomyelin (SM) is the most abundant phospholipid in the plasma, next to phosphatidylcholine (PC), its physiological function in plasma is unclear. Here we employed plasma from various genetic models of mice which naturally differ in their plasma SM/PC ratios, to study the role of SM as a modulator of LCAT, the enzyme responsible for HDL maturation and the synthesis of cholesteryl esters (CE) in normal plasma. Serine palmitoyltransferase deficient mice, and SM synthase deficient mice, both of which have below normal SM/PC ratios, showed significantly elevated LCAT activities when assayed with the endogenous substrates. On the other hand, LDL receptor knockout mice, and apo E knockout mice, both of which have high SM/PC ratios, had markedly reduced (-80%) LCAT activities. The LCAT levels in plasma, as assayed with an exogenous substrate, were similar in all groups, except for a 45% decrease in apo E knockout mice. Plasma samples with high SM/PC ratios had lower percentage of 20:4, 22:5, and 22:6 CE all of which are formed by LCAT, and a higher percentage of the atherogenic 18:1 CE which is mainly derived from the action of liver ACAT, showing that in vivo, the contribution of LCAT to plasma CE is reduced while that of liver ACAT is increased. These results show that SM is a physiological modulator of LCAT activity as well as plasma CE composition, and this may contribute to the previously reported pro-atherogenic effect of high plasma SM levels.
The Mechanism of Staining Explained on A Chemical Basis II. General Presentation

At present the division of the factors influencing staining into those supporting a chemical mechanism or those supporting what is known as “adsorption” mechanism is questioned because the latter t...
Informed Consent in the Post-Modern Era

The doctrine of informed consent' is intended to get physicians to talk to their patients so that patients can make reasonably knowledgeable choices about whether to undergo particular forms of medical care. Although the law has long prohibited treatment without the patient's consent,2 physicians have resisted the idea that treatment decisions ultimately are for the patient to make. Only recently have physicians been willing to disclose information about the benefits and risks of recommended thera-
A model for analysis and quantification of ion scattering spectroscopy data

Abstract An improved model has been developed for numerically fitting experimental ion scattering spectroscopy data. This model is a combination of the models described previously by Nelson [J. Vac. Sci. Technol. A 4 (1986) 1567] and Young and Hoflund [Anal. Chem. 60 (1988) 269]. It allows for quantification of the neutralization decay rate, accurate fitting of the different elemental peak shapes, extracting information which is usually difficult to obtain due to poor mass resolution, subtraction of the inelastic background and providing a measure of the composition of the outermost atomic layer. The model has been used to analyze ISS spectra obtained from isotopically pure 24 Mg and Mg of natural abundance (79% 24 Mg, 10% 25 Mg and 11% 26 Mg). The factors which influence spectral (mass) resolution have been examined using the model, and calculated results show that both the width of the scattering angle and the energy spread of the primary ion beam significantly affect resolution.
The relationship between the Gompertz constant and maximum potential lifespan; its relevance to theories of aging.

Abstract A correlation between the two aging parameters, the Gompertz constant, α and the maximum potential lifespan T is obtained. The product of α and T lies between 2 and 12 for mammals which have ceased to grow in their adult years, fish which continue to grow throughout life and rotifers, which have a constant number of cells. Since T is related to the metabolic rate, m, as m − 3 4 , then α must be related to the metabolic rate as m + 3 4 . It is suggested that somatic mutations play a lesser role than metabolism in aging.
Epidemiological estimates of risk in the process of becoming dependent upon cocaine: cocaine hydrochloride powder versus crack cocaine.

Rationale To estimate the risk of experiencing clinical features of cocaine dependence within 1–2 years of starting cocaine use, and to examine whether crack smoking might increase this risk.
Dislocations and Pinning Points

Early interactions with Jaques Friedel are recalled. Some aspects of his early work on dislocations are related to current theoretical challenges. Some new challenges based on configurations revealed by atomistic simulations are discussed.
Bridge fatigue assessment and management using reliability-based crack growth and probability of detection models

This paper focuses on conducting lifetime performance assessment and management of aging steel bridges under fatigue by integrating three prediction models: fatigue reliability model (FRM), crack growth model (CGM), and probability of detection (PoD) model. A novel approach using these models is proposed for planning interventions on fatigue sensitive structures. Based on information from field monitoring and/or non-destructive evaluation, prediction models are developed to (a) estimate the time-dependent fatigue performance using FRM, (b) provide the time-dependent crack growth using CGM, and (c) quantify the detection capability associated with fatigue cracks using PoD model. In order to assess and manage bridge fatigue life, the three models are combined based on two parameters (i.e., number of cycles, crack size). As an illustration, the combined approach is used for fatigue assessment and management of an existing bridge.
Permeability of thermally damaged skin II: immediate influences of branding at 60°C on hairless mouse skin permeability

Abstract Dry heat burns of incrementally increased duration (15–960 seconds) have been administered to freshly sacrificed mice with a thermostated branding iron maintained at 60°C. The association between extent of burn damage (shallow to deep tissue damage) and permeability was studied using water, methanol, ethanol, butanol, hexanol, and octanol as permeants. Thermal effects were measured as the ratio of a burned surface permeability to a normal skin section permeability in the same animal. Branding for brief times produced similar effects as scalding at 60°C for equivalent durations, 1–5 to 2-fold increases for water, methanol, and ethanol and 3-to 4-fold increases for the higher alkanols. There appears to be a gradual, steady increase in permeability with duration of burning. Permeability alteration was both qualitatively and quantitatively analogous to that seen previously with burns inflicted with 60°C water, indicating that at this temperature the method of burning is not a principal factor in altering permeability of the tissue.
A δ34SSO4 approach to reconstructing biogenic pyrite burial in carbonate-evaporite basins: An example from the Ara Group, Sultanate of Oman

Carbonate-associated sulfate (CAS) has the potential to generate high-resolution records of seawater sulfate (δ^(34)S_(SW)) that improve upon existing evaporite-based records. With improved resolution, however, significant isotopic offsets have become apparent between the evaporite and CAS proxies. Here we present high-resolution δ^(34)S measurements of both these proxies from the Ara Group, Sultanate of Oman, a series of six carbonate-evaporite sequences deposited ca. 547–540 Ma. The δ^(34)S_(CAS) from Ara carbonates show little scatter and provide our estimate of δ^(34)S_(SW). Repeated enrichments (as much as 4‰ relative to δ^(34)S_(CAS)) were observed in floor and roof anhydrite units (δ^(34)S_(EVAP)) bounding the Ara carbonates. These enrichments cannot be explained by secular variation or from isotopic fractionation during evaporite deposition and require the existence of an additional ^(34)S-depleted sink, which we attribute to H_(2)S production via ongoing bacterial sulfate reduction during evaporite deposition. To preserve this isotope signature, the resulting sulfide must be sequestered as pyrite. The magnitude of the resulting δ^(34)S_(EVAP) offset (relative to CAS) is a function of local pyrite burial (f_(pyr)). In periods of low pyrite burial, it is possible for δ^(34)S_(EVAP) to be depleted relative to δ^(34)S_(SW), whereas during episodes of substantial pyrite burial (f_(pyr) > 0.05), δ^(34)S_(EVAP) can be strongly enriched relative to δ^(34)S_(SW). Our data suggest that local fpyr of ~0.13 is consistent with the observed δ^(34)S_(EVAP) enrichments found in the Ara Group anhydrites. Such elevated pyrite burial in evaporitic settings requires a substantial iron source, supporting possible ferruginous ocean conditions across the Ediacaran-Cambrian boundary. Isotopic offsets between paired δ^(34)S_(CAS)-δ^(34)S_(anhydrite) data may thus serve as an independent proxy for marine redox through time, in addition to quantifying the importance of microbial activity in a setting where direct evidence (e.g., total organic carbon or biomarkers) may be scarce and physical processes are thought to dominate.
ENHANCEMENT OF PLASMA DENSITY FLUCTUATIONS BY NONTHERMAL ELECTRONS

In a plasma in thermal equilibrium, the spectrum of electron density fluctuations that have a wavelength longer than the Debye length has a sharp maximum near the electron plasma frequency. In this paper, the effect of a non-Maxwellian electron velocity distribution on the spectrum of electron density fluctuations is computed for frequencies near the electron plasma frequency. The electron velocity distribution is assumed to be isotropic but not necessarily Maxwellian and the effects of electron-ion collisions are included. The results show how the presence of a small number of energetic electrons can enhance the intensity of the fluctuations near the plasma frequency, provided the Landau damping resulting from these energetic electrons is greater than both the collision damping and the Landau damping caused by the ambient electrons. The results are applied to the ionosphere radar-backscatter experiments, where the energetic electrons are photoelectrons produced by solar uv radiation. In the case of the Arecibo radar experiments, the intensity of the fluctuations near the electron plasma frequency is estimated to be enhanced at plasma frequencies greater than about 4 or 5 Mc/sec.
Reversible ADP-ribosylation of the 78 kDa glucose-regulated protein

Starvation of Mouse hepatoma cells for essential amino acids or glucose results in the mono-ADP-ribosylation of the 78 kDa glucose-regulated protein, GRP78. Here we show that the ADP-ribosylated and non-ADP-ribosylated forms of GRP78 are interconvertible during tryptophan starvation and refeeding. In addition, the ADP-ribosylation of GRP78 was shown to be reversible even during nutritional stress. The overexpressed pool of non-ADP-ribosylated GRP78 synthesized during tunicamycin treatment was available for ADP-ribosylation during subsequent amino acid starvation, especially in the absence of tunicamycin. The reversible ADP-ribosylation of GRP78 could be part of a metabolic control mechanism in operation during nutritional stress.
Abstract: Comparing Semiparametric and Parametric Methods for Modeling Interactions Among Latent Variables

Many approaches have been proposed to estimate interactions among latent variables. These methods often assume a specific functional form for the interaction, such as a bilinear interaction. Theory is seldom specific enough to provide a functional form for an interaction, however, so a more exploratory, diagnostic approach may often be required. Bauer (2005) proposed a semiparametric approach that allows for the estimation of interaction effects of unknown functional form among latent variables. A structural equation mixture model (SEMM) is first fit to the data. Then an approximation of the interaction is obtained by aggregating over the mixing components. A simulation study is used to examine the performance of this semiparametric approach to two parametric approaches: the latent moderated structures approach (Klein & Moosbrugger, 2000) and the unconstrained product-indicator approach (Marsh, Wen, & Hau, 2004). Data were generated from four functional forms: main effects only, quadratic trend, bilinear interaction, and exponential interaction. Estimates of bias and root mean squared error of approximation were calculated by comparing the surface used to generate the data and the model-implied surface constructed from each approach. As expected, the parametric approaches were more efficient than the SEMM. For the main effects model, bias was similar for both the SEMM and parametric approaches. For the bilinear interaction, the parametric approaches provided nearly identical results, although the SEMM approach was slightly more biased. When the parametric approaches assumed a bilinear interaction and the data were generated from a quadratic trend or an exponential interaction, the parametric approaches generated biased estimates of the true surface. The SEMM approach approximated the true data generation surface with a similarly low level of bias for all the nonlinear surfaces. For example, Figure 1 shows the true surface for the bilinear interaction along with the SEMM estimated average surface. The results suggest that the SEMM approach can provide a relatively unbiased approximation to variety of nonlinear relationships among latent variables.
Focus on personal operational discipline to get work done right

A focus on operational discipline (OD) is typically an important factor in helping organizations achieve excellent safety performance by preventing injuries and serious incidents. Programs to improve OD must include both an organizational focus for site leadership to implement appropriate systems and a personal focus for workers at all levels to complete their work the right way, every time, following these systems. This article will discuss DuPont's OD program with emphasis on the personal focus needed to consistently get work done correctly and safely. © 2012 American Institute of Chemical Engineers Process Saf, 2012.
A Certified Nurse-Midwife’s Perspective on Intrapartum Biochemical Monitoring of the Fetus

Ethical use of resources is essential. Only 40 percent of pregnant women in New Mexico receive adequate prenatal care. This state has ranked worst in the nation in the proportion of women receiving late or no prenatal care. This is a problem in other areas of the United States as well as the world. How many people can we provide prenatal care to for the cost of one machine or one test? We should not do without the technological advances, but we need to keep in mind that these advances are expensive and there must be a balance.
A case–control analysis of oral contraceptive use and breast cancer subtypes in the African American Breast Cancer Epidemiology and Risk Consortium

Recent oral contraceptive (OC) use has been consistently associated with increased risk of breast cancer, but evidence on specific breast cancer subtypes is sparse. We investigated recency and duration of OC use in relation to molecular subtypes of breast cancer in a pooled analysis of data from the African American Breast Cancer Epidemiology and Risk Consortium. The study included 1,848 women with estrogen receptor-positive (ER+) breast cancer, 1,043 with ER-negative (ER-) breast cancer (including 494 triple negative (TN) tumors, which do not have receptors for estrogen, progesterone, and human epidermal growth factor 2), and 10,044 controls. Multivariable polytomous logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for exposure categories relative to never use, controlling for potential confounding variables. OC use within the previous 5 years was associated with increased risk of ER+ (OR 1.46, 95% CI 1.18 to 1.81), ER- (OR 1.57, 95% CI 1.22 to 1.43), and TN (OR 1.78, 95% CI 1.25 to 2.53) breast cancer. The risk declined after cessation of use but was apparent for ER+ cancer for 15 to 19 years after cessation and for ER- breast cancer for an even longer interval after cessation. Long duration of use was also associated with increased risk of each subtype, particularly ER-. Our results suggest that OC use, particularly recent use of long duration, is associated with an increased risk of ER+, ER-, and TN breast cancer in African American women. Research into mechanisms that explain these findings, especially the association with ER- breast cancer, is needed.
Intermittent Enteral Feeding in Mechanically Ventilated Patients: The Effect on Gastric pH and Gastric Cultures

Objective To evaluate the effect of intermittent (16 h/d) enteral feeding (IEF) on gastric pH and gastric microbial growth in mechanically ventilated patients. Design Prospective, case-controlled study. Setting Medical ICU and infectious disease research laboratory in a university hospital. Patient population Thirteen mechanically ventilated patients receiving continuous enteral feeding (CEF). Methods Gastric pH and quantitative gastric cultures were obtained while patients received CEF. Each patient's feeding schedule was changed to IEF. Daily gastric pH and quantitative gastric cultures were obtained for 5 consecutive days. Results Gastric microbial growth was found in 85% (11/13) of patients receiving CEF. Implementation of IEF did not clear gastric microbial growth, as only one patient subsequently reverted to negative culture. Similar gastric microbial growth continued in 90% (10/11) of patients after institution of IEF. Gastric pH did not decrease with the administration of IEF (gastric pH with IEF, 3.8±0.6 vs 4.7±0.5 with CEF (not significant [NS]). The amount of microbial growth was also unchanged with IEF (total growth with IEF, 7.8×10 5 ±5.2×10 5 cfu/mL vs 8.7×10 5 ±4.6×10 5 cfu/mL with CEF) (NS). Thirty-eight percent (5/13) of patients developed new Gram-negative rod growth in gastric cultures while receiving IEF. Gram-negative rod isolates increased from 25% of total isolates (CEF) to 40% (IEF). Conclusion Our preliminary data suggest gastric pH was not lowered and existing microbial growth was not cleared in ventilated patients receiving IEF after previously receiving CEF. Further controlled study in a larger group of patients is necessary to determine whether IEF is of benefit in decreasing gastric colonization and nosocomial pneumonia.
Effective contraceptive counseling with adolescents in a nurse-based setting

Nurses are often on the frontline with adolescents. They serve an important role in providing comprehensive education and counseling on reproductive health issues, including contraception. This article presents an overview of the common methods of contraception used by adolescents, with a focus on effective counseling. The nursing goal is to help teens prevent unintended pregnancies.
Further Theoretical Considerations for Time-Reversal Music Imaging of Extended Scatterers

This research develops further the theory of time-reversal multiple signal classification (MUSIC) imaging of extended (non-point-like) scatterers developed in earlier papers.
Multimodality imaging of the Essure tubal occlusion device

The Essure device is a permanent birth-control device, which is gaining popularity. The micro-inserts are composed of metallic elements that can be seen on radiography, computed tomography, ultrasound, and magnetic resonance imaging. Knowledge of the normal location and appearance of the Essure device will ensure appropriate patient care. The purpose of this review is to describe the Essure tubal occlusion device and illustrate its normal and abnormal appearance using various imaging methods.
The impact of deer on relationships between tree growth and mortality in an old-growth beech-maple forest

White-tailed deer have been at high levels in the northeastern forests of the United States for decades and have strongly influenced forest dynamics. In this long-term study, we found that the composition of the overstory and understory assemblages of an old-growth beech-maple forest differed significantly. We used exclosures to test the hypothesis that deer contributed to these differences by differentially influencing the relationship between growth and mortality among seedlings of the six most abundant tree species. In the absence of deer, we found that the mortality of the six species decreased with increased growth and that interspecific differences in the relationships between growth and mortality coincided with previously observed shade-tolerance rankings. In the presence of deer, mortality decreased with growth only for the browse tolerant species (American beech, black cherry, and sugar maple). Mortality did not decrease with growth for preferred browse species (oak species, ash species, and red maple), rather, this relationship was eliminated in the presence of deer. The changes in growth and mortality relationships in the presence of browsing generally corresponded to observed changes in seedling density following the removal of deer. Sugar maple, ash, black cherry, and total stem density increased in the absence of deer. Our results suggest that the relationship between survival and growth in the understory, a metric of shade tolerance, is a fairly plastic response that varies depending upon the presence and absence of herbivores. Our results indicate that deer have contributed to the differences between understory and overstory vegetation, with browse tolerant species increasing in abundance at the expense of preferred browse species.