cssi/SciSciGPT-SciSciNet huggingface dataset:
Relationship between drug dissolution and leaching of plasticizer for pellets coated with an aqueous Eudragit® S100:L100 dispersion

Abstract In order to investigate the relationship between drug dissolution and leaching of plasticizer, theophylline pellets coated with 30% (w/w) Eudragit ® S100:L100 (1:1) plasticized with different levels of triethyl citrate (TEC) were prepared. The influence of storage conditions on the dissolution profile of theophylline and leaching of TEC was determined. Theophylline was found to dissolve completely from pellets coated with Eudragit ® S100:L100 (1:1) plasticized with 50% TEC at pH 6.0 after 2 h. The shape of the pellets was maintained during dissolution testing. Cracks due to the leaching of TEC were observed in the scanning electron micrographs (SEMs) following dissolution testing at pH 6.0. Both the dissolution of theophylline and the leaching of TEC decreased during storage due to further coalescence of the acrylic polymers. The dissolution profiles of theophylline showed a biphasic pattern and the lag times were estimated as the time points at which a second, rapid release of theophylline was initiated. Subsequently, the percent of TEC leached at the lag time was calculated. While the lag time was increased by storage time and humidity, the percent of TEC leached at the lag time was unchanged as a function of storage condition and was dependent on the initial TEC levels in the films. In conclusion, the plasticizer content in the film coating influenced the dissolution profile of theophylline from pellets coated with Eudragit ® S100:L100 (1:1). A large amount of the TEC was leached from the enteric films before drug release was initiated and a TEC level of approximately 30% in the films, based on the polymer weight, was the critical amount of TEC for initiating drug release during dissolution testing at pH 6.0. While enteric films are more soluble and dissolve faster at higher pH values, the kinetics of plasticizer release was one of the important factors controlling the dissolution of drugs at pH 6.0, at which pH the enteric polymers were insoluble.
Cytokine profiling in acute anterior cruciate ligament injury.

Purpose To evaluate the presence and relative concentrations of cytokines, known to be involved in the inflammatory cascade, in acute anterior cruciate ligament (ACL) injury. Methods We evaluated an extensive cytokine profile in synovial fluid from 12 patients with acute ACL injury undergoing arthroscopy compared with 15 control subjects using a BioPlex assay (Bio-Rad Laboratories, Hercules, CA) to measure the concentration of 17 inflammatory cytokines. Results In patients with acute ACL injury compared with asymptomatic control subjects, the following cytokines were identified at significantly increased concentrations ( P U test) compared with control samples: interleukin 6 (105 ± 72 v 0 ± 0 pg/ml), interferon γ (1,544 ± 608 v 9 ± 7.5 pg/ml), macrophage inflammatory protein 1β (16 ± 3.8 v 0.3 ± 0.2 pg/ml), and monocyte chemotactic protein 1 (35 ± 13 v 0.5 ± 0.4 pg/ml). There was no case of a cytokine exhibiting increased levels in asymptomatic compared with symptomatic knee samples. Conclusions This investigation identified 4 specific cytokines (interleukin 6, interferon γ, monocyte chemotactic protein 1, and macrophage inflammatory protein 1β) out of a panel of 17 inflammatory molecules for which the levels were consistently elevated in the context of ACL injury compared with non-painful, non–acutely injured knees in a volunteer population. Level of Evidence Level IV, prognostic case series.
Micro-optic laser beam scanner

Laser beam scanners are used to modulate the direction of laser light, and are critical components of airborne and space-based LIDAR and optical communications systems. We report here a laser beam steering device design based on dithering two complementary (positive and negative) binary optic microlens arrays. When the two microlenses are translated relative to one another in the plane parallel to their surfaces, a light beam can be scanned and controlled in two directions. The first demonstration of this device concept was reported by Lincoln Laboratory. We have demonstrated a miniaturized version of this concept consisting of a pair of 6-mm-aperture binary optic microlens arrays designed for HeNe laser wavelength.
Heterogeneity in an isolated membrane protein. Has the 'authentic cytochrome oxidase' been identified?

The criteria of homogeneity or native state of a protein are prone to become ambiguous when applied to membrane proteins, such as cytochrome-c oxidase, which are purified by extraction with detergents. Properties of the purified material depend on the detergent used and on details of the purification protocol followed with any single batch of a preparation. We present arguments to show that the evidence presently available in published form does not justify the designation [(1987) J. Biol. Chem. 262 3160–3164] of one type of preparation as being closer to the native state than others.
Bays-of-Maine Igneous Complex

A recently discovered gabbroic-granitic complex closely resembles other huge stratiform or lopolithic bodies. The complex was emplaced within and below a thick volcanic pile that formed slightly before the gabbroic phase, Folding, faulting, and locally intense shearing hav e affected the complex and its country rock. Younger stocklike masses of hornblende and biotite granite cut indiscriminately the igneous complex and adjacent rocks and appear emplaced by ring-fracture sloping.
Fundamental reference data: where have we come in five years?

Abstract The requirements of atomic reference data for analytical atomic spectroscopy are reviewed in the light of the recommendations made at a conference in Scarborough, Ontario, in 1987. Progress has been significant in determination of atomic structure, transition probabilities, and data base management. Progress in the development of data for line shapes and fine-structure is less evident.
A coupled channels approach to Penning ionization of Ar BY He*(Is2s, 3S)☆

Abstract A discretization procedure has been applied to the continuum of electronic states encountered in Penning ionization (PI) and associative ionization (AI) of an atom B by an excited (metastable) atom A * , where A * + B → A + B + + e − (PI) and A * + B → AB + + e − (AI). Within the context of discretization, a procedure has been introduced which treats the collision dynamics of PI and AI processes in terms of a small number of two-state coupled equations, each associated with a particular amount of kinetic energy ϵ removed by the emitted electron. Application has been made to PI of Ar by He * (1s2s, 3 S). Calculated results of partial ionization cross sections as a function of ϵ are reported and show excellent agreement with experimental measurements of the energy distribution of emitted electrons in PI and AI of Ar by He * (1s2s, 3 S).
Evaluation of the accuracy of brain optical properties estimation at different ages using the frequency-domain multi-distance method

NIRS is safe, non-invasive and offers the possibility to record local hemodynamic parameters at the bedside, avoiding the transportation of neonates and critically ill patients. In this work, we evaluate the accuracy of the frequency-domain multi-distance (FD-MD) method to retrieve brain optical properties from neonate to adult. Realistic measurements are simulated using a 3D Monte Carlo modeling of light propagation. Height different ages were investigated: a term newborn of 38 weeks gestational age, two infants of 6 and 12 months of age, a toddler of 2 year (yr.) old, two children of 5 and 10 years of age, a teenager of 14 yr. old, and an adult. Measurements are generated at multiple distances on the right parietal area of head models and fitted to a homogeneous FD-MD model to estimate the brain optical properties. In the newborn, infants, toddler and 5 yr. old child models, the error was dominated by the head curvature, while the superficial layer in the 10 yr. old child, teenager and adult heads. The influence of the CSF is also evaluated. In this case, absorption coefficients suffer from an additional error. In all cases, measurements at 5 mm provided worse estimation because of the diffusion approximation.
Prevalence and characteristics of children with serious hearing impairment in metropolitan Atlanta, 1991-1993.

Objectives. There is a paucity of data describing the epidemiology of serious hearing impairment among children in the United States. This report provides information on the prevalence of serious hearing impairment among children born in the 1980s and living in the metropolitan Atlanta area in 1991–1993 and on the characteristics of children with serious hearing impairment. Methods. Data for this report are drawn from the Metropolitan Atlanta Developmental Disabilities Surveillance Program, an ongoing, active case-ascertainment system for mental retardation, cerebral palsy, hearing impairment, and vision impairment among children 3 to 10 years of age. Hearing impairment was defined as a bilateral, pure-tone hearing loss at frequencies of 500, 1000, and 2000 Hz averaging 40 decibels or more, unaided, in the better ear. Both severity and type of hearing loss were examined. Cross-sectional as well as birth cohort prevalence rates of serious hearing impairment were computed by sex and by race. The presence of mental retardation, cerebral palsy, vision impairment, or a seizure disorder was also assessed. An attempt was made to determine the probable etiology of a subset of the cases. Results. The average, annual prevalence rate for moderate to profound hearing loss was 1.1 per 1000. The prevalence rate increased steadily with age. Ninety percent of all cases for which the type of loss was recorded were sensorineural. The highest rate was seen among black male children (1.4 per 1000). Thirty percent of case children had another neurodevelopmental condition, most frequently mental retardation. Black male children also experienced the highest rate of presumed congenital hearing impairment. The mean age at which children with presumed congenital hearing impairment first met the surveillance case definition was 2.9 years. A probable etiology could only be found for 22% of cases born in the study area. Conclusions. The data presented here provide information on the descriptive epidemiology of serious hearing impairment among United States children. The reasons for the higher rates among black children, especially males, may be a fruitful direction for further research.
Effects of unpredictability of shock on incidence of gastric lesions and heart rate in immobilized rats

Abstract Degree of gastric ulceration and heart rate were assessed over a 19 hr immobilization period during which groups of rats received either (I) CS presentations, (II) CS presentations 50% of which were paired with a US, (III) CS presentations all of which were paired with the US, (IV) 50% CS-US pairings with the number of US presentations equal to Group III or (V) unrelated presentations of the CS and US. The unpredictable condition of Group V resulted in significantly greater ulceration than seen in Group I with the other groups falling between these extremes. While Groups II, III, and IV showed reliable and equivalent bradycardic responses to the CS, the pre-CS heart rate measure failed to discriminate among groups.
Polarizability and spin density correlate with the relative anaerobic biodegradability of alkylaromatic hydrocarbons.

Polarizability ((alpha) and spin density (SD) of benzyl radical intermediates calculated using Gaussian O3 were correlated with the extent of anaerobic biodegradation for 17 C1 to C4 parent alkylbenzenes. The percent anaerobic biodegradation of the hydrocarbon series was determined in a previous study using an inoculum from a gas condensate-contaminated aquifer incubated under sulfate-reducing conditions. Many of the parent compounds are known to be biodegraded in the absence of oxygen by fumarate addition reactions. Percent biodegradation over a 100 day incubation (predicted) = -1.044 + 908.271SD - 586.197 (R2 = 0.839; all p-values < or = 0.058). This correlation suggests that compounds forming more stable alkylbenzyl radical intermediates biodegrade by fumarate addition more slowly than their counterparts forming less stable radicals. More highly substituted molecules including isopropylbenzene, 1-ethyl-2,6-dimethylbenzene and 1-ethyl-3,4-dimethylbenzene did not fit the model. The assumption of biodegradation by fumarate addition reaction was independently verified with several substrates. These findings help form a basis for predicting the relative rate of alkylbenzene metabolism in anaerobic environments.
Density in Arbitrary Semigroups

We introduce some notions of density in an arbitrary semigroup S which extend the usual notions in countable left amenable semigroups in which density is based on Folner sequences. The new notions are based on nets of finite sets. We show that under certain conditions on the nets and on S these notions relate nicely to some established notions of size in S such as central, syndetic, and piecewise syndetic. And we investigate the conditions under which these notions have other desirable properties such as translation invariance. We obtain new information about the algebraic structure of the Stone-Cech compactification β S of S and derive generalizations of some known Ramsey Theoretic results, including Bergelson's density version of Schur's Theorem.
Loss of pleckstrin defines a novel pathway for PKC-mediated exocytosis.

Pleckstrin, the platelet and leukocyte C kinase substrate, is a prominent substrate of PKC in platelets, monocytes, macrophages, lymphocytes, and granulocytes. Pleckstrin accounts for 1% of the total protein in these cells, but it is best known for containing the 2 prototypic Pleckstrin homology, or PH, domains. Overexpressed pleckstrin can affect polyphosphoinositide second messenger–based signaling events; however, its true in vivo role has been unknown. Here, we describe mice containing a null mutation within the pleckstrin gene. Platelets lacking pleckstrin exhibit a marked defect in exocytosis of δ and α granules, αIIbβ3 activation, actin assembly, and aggregation after exposure to the PKC stimulant, PMA. Pleckstrin-null platelets aggregate normally in response to thrombin, but they fail to aggregate in response to thrombin in the presence of PI3K inhibitors, suggesting that a PI3K-dependent signaling pathway compensates for the loss of pleckstrin. Although pleckstrin-null platelets merged their granules in response to stimulation of PKC, they failed to empty their contents into the open canalicular system. This might be attributable to impaired actin assembly present in cells lacking pleckstrin. These data show that pleckstrin regulates the fusion of granules to the cell membrane and is an essential component of PKC-mediated exocytosis.
The Liouville theorem under second order differentiability assumption

Abstract Iwaniec and Martin proved that in even dimensions n ≥ 3 , W loc 1 , n / 2 conformal mappings are Mobius transformations and they conjectured that it should also be true in odd dimensions. We prove this theorem for a conformal map f ∈ W loc 1 , 1 in dimension n ≥ 3 under one additional assumption that the norm of the first order derivative | D f | satisfies | D f | p ∈ W loc 1 , 2 for p ≥ ( n − 2 ) / 4 . This is optimal in the sense that if | D f | p ∈ W loc 1 , 2 for p ( n − 2 ) / 4 , it may not be a Mobius transform. This result shows the necessity of the Sobolev exponent in the Iwaniec–Martin conjecture. Meanwhile, we show that the Iwaniec–Martin conjecture can be reduced to a conjecture about the Caccioppoli type estimate.
Electron Energy Deposition in Multilayer Geometries

A high precision calorimetric method has been employed to measure electron energy deposition profiles in multilayer configurations for normally incident source electrons at an energy of 1.0 MeV. The results are compared with the predictions of a coupled electron/ photon Monte Carlo transport model. Excellent agreement between theory and experiment is obtained for an Al/Au/Al configuration, while significant discrepancies are observed in the case of C/Au/C and Be/Au/Be configurations. Several potential problems are discussed but no satisfactory explanation for the discrepancies has been found.
The Role of Circadian Rhythm in the Pathogenesis of Colorectal Cancer

The circadian clock controls many cellular processes, some of which are key to tumor suppression, including cell proliferation and apoptosis, DNA repair, metabolism, hormone signaling, and immune function. The association between altered circadian clock function and increased risk of colorectal cancer is increasingly evident from epidemiologic, preclinical, and clinical studies. In this review, we discuss several distinct mechanisms by which altered components of the circadian clock might promote intestinal tumorigenesis. We also review the progress in identifying circadian and clock-based molecular processes that might be targeted to promote the prevention and control of colorectal cancer.
Riparian Area Protection and Outdoor Recreation: Lessons from the Northwest Forest Plan

The Northwest Forest Plan required the US Forest Service (USFS) to shift its management focus to ecological values rather than the utilitarian ones that had dominated forest policy in the region. T...
Combining neural networks using the ranking figure of merit

The neural network community has recently shown a considerably interest in combining multiple neural networks (NNs). Such a combination usually improves the performance over a single NN because different NNs can complement each other. To achieve improved performance, the individual NNs must be trained independently. In this paper, three NNs are trained using the Ranking Figure of Merit objective function (with different parameters) that we introduced last year. We introduce a new method of combining NNs, which we call pooled objective function. The objective function is calculated for each NN and averaged to arrive at the pooled objective function. The combined vote is the class with the best pooled objective function. It is shown that the frequently used scheme of averaging the outputs is equivalent to the pooled mean squared error.
Proton storage ring — the man/machine interface

The human interface of the Proton Storage Ring Control System at Los Alamos is described in some detail, together with the software environment in which operator interaction programs are written. Some examples of operator interaction programs are given.
Electrophysiological recordings from behaving animals—going beyond spikes

Most of our current knowledge about the neural control of behavior is based on electrophysiology. Here we review advances and limitations of current electrophysiological recording techniques applied in behaving animals. Extracellular recording methods have improved with respect to sampling density and miniaturization, and our understanding of the nature of the recorded signals has advanced. Juxtacellular recordings have become increasingly popular as they allow identification of the recorded neurons. Juxtacellular recordings are relatively easy to apply in behaving animals and can be used to stimulate individual neurons. Methods for intracellular recordings in awake behaving animals also advanced, and it has become clear that long-duration intracellular recordings are possible even in freely moving animals. We conclude that the electrophysiological methods repertoire has greatly diversified in recent years and that the field has moved beyond what used to be a mere spike counting business.
Statistical approach to model matching

densities and the projection model is linear. Several linear projection and feature models are discussed. Evidence isprovided to show that Normal feature deviation models can be appropriate for computer vision matching problems.Relation to other work and possible extensions and application areas are discussed.
Host specificity of insect herbivores in tropical forests.

Studies of host specificity in tropical insect herbivores are evolving from a focus on insect distribution data obtained by canopy fogging and other mass collecting methods, to a focus on obtaining data on insect rearing and experimentally verified feeding patterns. We review this transition and identify persisting methodological problems. Replicated quantitative surveys of plant–herbivore food webs, based on sampling efforts of an order of magnitude greater than is customary at present, may be cost-effectively achieved by small research teams supported by local assistants. Survey designs that separate historical and ecological determinants of host specificity by studying herbivores feeding on the same plant species exposed to different environmental or experimental conditions are rare. Further, we advocate the use of host‐specificity measures based on plant phylogeny. Existing data suggest that a minority of species in herbivore communities feed on a single plant species when alternative congeneric hosts are available. Thus, host plant range limits tend to coincide with those of plant genera, rather than species or suprageneric taxa. Host specificity among tropical herbivore guilds decreases in the sequence: granivores>leaf-miners>fructivores>leaf-chewers=sap-suckers>xylophages>root-feeders, thus paralleling patterns observed in temperate forests. Differences in host specificity between temperate and tropical forests are difficult to assess since data on tropical herbivores originate from recent field studies, whereas their temperate counterparts derive from regional host species lists, assembled over many years. No major increase in host specificity from temperate to tropical communities is evident. This conclusion, together with the recent downward revisions of extremely high estimates of tropical species richness, suggest that tropical ecosystems may not be as biodiverse as previously thought.
Nebulized PPARγ agonists: a novel approach to augment neonatal lung maturation and injury repair in rats.

Nebulized PPARγ agonists: a novel approach to augment neonatal lung maturation and injury repair in rats
Theory of deep impurities in silicon-germanium alloys

Calculations of the deep-energy levels of substitutional ${\mathrm{sp}}^{3}$-bonded defects in ${\mathrm{Si}}_{x} {\mathrm{Ge}}_{1\ensuremath{-}x}$ alloys suggest that the standard shallow dopants As and P and isoelectronic C defect may become deep traps for $x\ensuremath{\simeq}0.2$.
Racialized social system and HIV infection: the case of African Americans

Analyses how HIV/AIDS has affected African Americans, who are acknowledged as a vulnerable racialized group, along with Puerto Ricans. Defines the term of racialized social system as a society where part of the stratification system is designed to reank people based on their racial classification. Sheds light on AIDS and ethnicity through copious use of figures and tables. Summarizes that there is little control over tehir own community economics for African Americans, legitimately, as HIV runs riot. Urges a race‐conscious approach to the HIV/AIDS epidemic.
Products of commutators and the order of a finite group

Let G be a finite nonabelian group. Define λ(G) to be the smallest positive integer such that every element of G′ is expressible as a product of λ(G) commutators. We show |G′|⩾(λ(G)+1)!(λ(G)−1)!. We use this result to prove a conjecture of V.G. Bardakov in the Kourovka notebook that λ(G)|G|⩽16, with the bound obtained only at the group S3.
Identification of the b, d, and e analogs of vitamin B12 as monocarboxylic acids by 15N NMR spectroscopy

15N NMR spectra of b−, d−, and e-cyanocobalamin (vitamin B12) and the products of their amidation with 15N-labeled ammonia show that these analogs are monocarboxylic acids of vitamin B12 which result from hydrolysis at the respective propionamide groups.
Access to Capital and Its Impact on Agrarian Structure and Productivity in Kenya

Access to capital and its distribution across agents can profoundly shape the structure and performance of an agrarian market economy.' It is conceptually useful to distinguish between ex ante and ex post capital access. Ex ante capital access denotes the ability of agents to finance production costs (e.g., labor and purchased inputs costs) which must be paid ex ante, that is, prior to the actual realization of production. Ex post capital access, that is access to capital after the realization of the production process, is of particular importance as an insurance substitute in low income agrarian economies where contingency markets are imperfect. Buoyant ex post capital access would permit an individual to stabilize consumption year to year even as production fluctuates annually. A number of theoretical models have ex-
Programmable CMOS/Memristor Threshold Logic

This paper proposes a hybrid CMOS/memristor implementation of a programmable threshold logic gate. In this gate, memristive devices implement ratioed diode-resistor logic, while CMOS circuitry is used for signal amplification and inversion. Due to the excellent scaling prospects and nonvolatile analog memory of memristive devices, the proposed threshold logic is in-field configurable and potentially very compact. The concept is experimentally verified by implementing a 4-input symmetric linear threshold gate with an integrated circuit CMOS flip-flop, silicon diodes, and Ag/a-Si/Pt memristive devices.
Discounting and sustainability: towards reconciliation

This paper examines the well-known tension between discounting and sustainability in the long-term management of environmental resources. The paper describes a rights-based ethical framework in which present decision-makers hold a moral duty to ensure that life opportunities are sustained from generation to generation. Maintaining opportunities requires that natural resources must be either conserved or replaced with proven substitutes that provide equivalent services. In this framework, discounting procedures are useful in characterizing decision-makers' preferences concerning tradeoffs between costs and benefits that arise at different points in time. Such preferences, however, are trumped by duties to posterity in cases where discounting favours the uncompensated depletion of resource stocks.
Experiments to investigate DCH phenomena with large-scale models of the Zion and Surry nuclear power plants

The Surtsey Test Facility and the Containment Technology Test Facility (CTTF) at Sandia National Laboratories (SNL) have been used to perform scaled experiments for the Nuclear Regulatory Commission (NRC) that simulate high-pressure melt ejection (HPME) accidents in a nuclear power plant (NPP). These experiments are designed to investigate the effects of direct containment heating (DCH) phenomena on the containment load. High-temperature, chemically reactive alumino (thermitic) melt is ejected by high-pressure steam into a scale model of either the Zion or Surry NPP. Integral effects tests under prototypic conditions have been performed to investigate the effects of dispersal of molten core materials on DCH loads, and to study the effects of Westinghouse plant configurations on DCH loads. In Westinghouse plants, there is (1) an intermediate compartment that is large compared with the reactor cavity but small compared with the main containment volume, and (2) no significant line-of-sight pathway for debris transport from the cavity to the main containment volume. Containment compartmentalization is the dominant mitigating feature for Zion, Surry, and most other pressurized water reactors. Experimental results will be used to further assess the applicability of existing DCH models to Westinghouse plants on DCH loads.
Evaluating health outcomes following a pharmacist-provided comprehensive pretravel health clinic in a supermarket pharmacy

Abstract Objectives To evaluate health outcomes and acceptance of pharmacists’ recommendations of travel health including prevalance of immunizations, sunburn, insect-borne diseases, traveler's diarrhea, and altitude sickness, and assess patient satisfaction with the pretravel health clinic. Design Retrospective cross-sectional study design. Setting Central Virginia, July 2011 to June 2012. Participants Patients 18 years and older who had an appointment with the pharmacist for pretravel health. Intervention Interview/survey administered to patients by telephone Main Outcome Measures Health outcomes, acceptance rates of pharmacist's travel health recommendations, and patient satisfaction. Results Of 356 patients eligible to participate in the study, 103 patients participated, 30 patients declined, and 223 patients could not be reached by telephone (29% response rate). Pharmacists’ recommendations for travel immunizations (100% acceptance rate for yellow fever and 82% for Typhoid) and nonpharmacologic preventive measures (prevention of sunburn, traveler's diarrhea, insect bites, and altitude sickness) were well accepted by respondents, and occurrence of these adverse events was low. Patients were satisfied overall with the education and services that the pharmacist delivered in the pretravel health clinic. Conclusion Pharmacists providing services in pretravel health clinics can have substantial impact on the health of patients traveling internationally.
Photopheresis in solid organ transplant rejection.

Photopheresis has become a key component in the therapeutic armamentarium of cutaneous T-cell lymphoma, graft-versus-host disease following stem cell transplant, and allograft rejection of solid organs such as heart. Although it is considered a new treatment modality in its present form, the field of phototherapy dates back thousands of years. In this review, the reader will learn more about the history of photopheresis and how it became a therapeutic alternative for patients with solid organ transplants. An extensive literature search will highlight the evidence-based benefits of photopheresis (or lack thereof). A discussion of the mechanism of action of photopheresis and the technical aspects of the procedure will also be covered. Since photopheresis may be the best tolerated form of immunomodulation, current promising, albeit preliminary data on its efficacy warrant further investigation and understanding. J. Clin. Apheresis 21:72–77, 2006. © 2006 Wiley-Liss, Inc.
Bioturbation as Factor in Hydrocarbon Generation--Example from Mowry Shale: ABSTRACT

The Lower Cretaceous Mowry Shale of the Western Interior has long been recognized as an oil source rock. Previous workers have shown that the Mowry displays distinct lateral changes in organic carbon content. Such variations have been ascribed to a dilution effect--siliciclastic swamping of the planktonic component in areas of rapid deposition. Examination of Mowry Shale fabric shows that sediment bioturbation was negligible in eastern Wyoming (central part of Albian seaway), but that the muds in western Wyoming (margin of seaway) were thoroughly bioturbated. Bioturbation was produced by deposit-feeding infauna; thus organic carbon was actively consumed and depleted in bioturbated muds. True source rock lithologies in the Mowry, as determined geochemically by Nixon, are l calized in areas where bioturbation of the sediment was minimal or absent. Bioturbation in the Mowry appears to reflect the degree of oxygenation, and hence the water depth, in the Albian seaway. Systematic decrease in bioturbation indicates the direction of the paleoslope. In initial basin reconnaissance, it should be possible to anticipate where the largest concentrations of organic carbon accumulated--downslope in deeper-water, less oxygenated, less bioturbated sediments. The undisturbed shale fabric characteristic of anaerobic environments may also influence the primary migration of oil. Fine-silt laminations, common in the Mowry Shale and other black shales, could serve as preferential avenues for migration; bioturbation obliterates these laminae and could inhibit migration. The distribution of oil fields in eastern Wyoming and southeastern Montana, within the laminated Mowry facies, supports this hypothesis. End_of_Article - Last_Page 685------------
Quantitative imaging of chemical composition using dual-energy, dual-source CT

Dual-energy x-ray material decomposition has been proposed as a noninvasive quantitative imaging technique for more than 20 years. In this paper, we summarize previously developed dual-energy material decomposition methods and propose a simple yet accurate method for quantitatively measuring chemical composition in vivo. In order to take advantage of the newly developed dual-source CT, the proposed method is based upon post reconstruction (image space) data. Different from other post reconstruction methods, this method is designed to directly measure element composition (mass fraction) in a tissue by a simple table lookup procedure. The method has been tested in phantom studies and also applied to a clinical case. The results showed that this method is capable of accurately measuring elemental concentrations, such as iron in tissue, under low noise imaging conditions. The advantage of this method lies in its simplicity and fast processing times. We believe that this method can be applied clinically to measure the mass fraction of any chemical element in a two-material object, such as to quantify the iron overload in the liver (hemochromatosis). Further investigations on de-noising techniques, as well as clinical validation, are merited.
The hydroxyethynyl radical (CCOH): an accessible isomer of the ketenyl radical (HCCO)?

Abstract The two lowest-lying states ( X 2 A′′ and A 2 A′) of the hydroxyethynyl radical (CCOH), an isomer of the ketenyl radical (HCCO), have been investigated theoretically using ab initio electronic structure theory. The ground and first excited electronic states of CCOH were determined to have trans -planar bent structures. At the TZ3P(2f,2d) CCSD(T) level of theory the two lowest-lying states of CCOH were predicted to lie 54.2 kcal/mol (2.35 eV, 19000 cm −1 ) and 65.8 kcal/mol (2.85 eV, 23000 cm −1 ) classically above the ground state of HCCO. Due to its large dipole moments and significantly large vibrational infrared (IR) intensities, the CCOH radical may be suitable for microwave and IR spectroscopic investigations.
Molecular recognition by artificial enzymes: Cyclic urea mimetics of alpha chymotrypsin

Molecular mechanics calculations are used to investigate the degree of structural preorganization and electrostatic complementarity for substrate binding exhibited by the cyclic urea mimetics of alpha chymotrypsin. The Amber molecular mechanics force field is used to calculate the “native” and complexed structures of a cation-binding mimetic precursor compound, as well as the structure of the cyclic urea compound containing an m-methylenehydroxy phenyl substituent, which mimics the action of the serine 195 residue in alpha chymotrypsin. Comparison of the native and complexed structures of the cation-binding precursor compound shows that this cyclic urea compound undergoes little conformational change upon substrate binding. Addition of the m-methylenehydroxy phenyl group is found to have little effect on the conformation of the macrocycle. Molecular electrostatic potential maps calculated in planes parallel to the average plane of the oxygen atoms of the macrocycle indicate that the orientation of the oxygen atoms directs the cationic end of the substrate into the electron-rich center of the macrocycle. The m-methylenehydroxy phenyl substituent affects the electrostatic potential pattern by pulling some of the electron density away from the center of the macrocycle. Similar structural and electrostatic comparisons are made with models of the active site of alpha chymotrypsin taken from the X-ray data.
Ecological assessment of self-protective devices in three profoundly retarded adults

Three profoundly retarded adults were observed in an experimental daycare program when they were not wearing self-protective restraints and when they were wearing them to prevent pica and rectal digging. The noncontingently applied devices did eliminate the target behaviors, but they also decreased social interactions between the subjects and their caretakers. A camisole was found to be even more restrictive than a fencing mask.
Antagonistic effects of perilymphatic calcium and magnesium on the activity of single cochlear afferent neurons.

Abstract The dependence of the spontaneous and sound driven activity of single cochlear nerve fibers on the calcium and magnesium content of the perilymph was studied by perfusion of the perilymphatic space. It was possible to study these effects under steady-state conditions by continuously perfusing scala tympani at low rates while simultaneously recording from units in the chinchilla auditory nerve. Preparations were stable for many hours. As previously reported [Robertson and Johnstone (1979) Pflugers Arch. 380, 7–12], perfusion with solutions containing elevated concentrations of magnesium reduces both the spontaneous and driven activity. When calcium was eliminated from the perfusate, activity was completely abolished for stimuli with sound pressure levels below 100 dB. During partial blocks, a relatively frequency-independent threshold elevation was seen for frequencies well below the characteristic frequency (CF) of the unit, with greater elevations closer to CF. When the threshold elevation at CF was 30–40 dB, the width of the ‘tip’ portion of the tuning curve was reduced, resembling that of naturally-occurring units with low spontaneous rates of discharge. These effects are similar to that of raising the criterion for response during threshold measurement and are probably related to a frequency-dependent nonlinearity exhibited by the motion of the basilar membrane. The dynamic range for the growth of average rate with level was increased and saturation was shifted to higher stimulus levels during elevated magnesium perfusion. Raising the calcium content of the perfusate increased both spontaneous and driven rates, even in the saturated portion of the rate-intensity plot. Under these conditions, the response of the unit may more directly correspond to the intracellular potential of the presynaptic hair cell. It is argued that the primary site of divalent cation interaction is in the control of transmitter release. Inner hair cells of the mammalian cochlea appparently do not release transmitter in the absence of a calcium influx. The size of the pool of ‘readily-available’ transmitter appears to be influenced by divalent cations. Even though this synapse is probably specialized for the transmission of auditory signals, the mechanism of synaptic transmission is probably not fundamentally different from that of other well-characterized synapses.
Instrumentation and techniques for high-resolution magnetic imaging

Recently-developed, high-resolution Superconducting QUantum Interference Device (SQUID) magnetometers can provide magnetic images of small objects with a signal-to-noise ratio and spatial resolution that are an order of magnitude better than is achievable with conventional SQUID magnetometers. The MicroSQUIDtm magnetometer has 4 channels, each of which is a differential magnetometer with a 3 mm diameter pick-up coil located less than 1.5 mm from the room-temperature region outside the Dewar. The system noise is approximately 100 fT/Hz1/2. We present magnetic field data recorded from several two-dimensional current distributions, and from the remanent magnetization in rocks, photocopier images, and magnetic contamination in metallic tubes. The system is capable of locating to better than 10 µm a straight wire carrying a 20 µA peak-to-peak sine wave current. The system can detect growth currents in a fertile chicken egg, and signals from a voluntarily-activated single motor unit in the human thumb. Magnetic fields produced by two-dimensional current distributions can be converted into current density images using Fourier-transform spatial filtering algorithms. This approach allows us to examine the difference between the imaging and localizing resolution of a magnetometer, and allows us to devise apodized pick-up coils with increased spatial resolution.
Relation of st-segment elevation after healing of acute myocardial infarction to the presence of left ventricular aneurysm

Persistent ST elevation after healing of myocardial infarction (MI) is often cited as an electrocardiographic sign of left ventricular (LV) aneurysm. This sign is rare in patients with coronary artery disease who have normal or only mildly deranged LV function and is most often associated with QRS patterns indicative of large MI, especially anterior wall MI. To determine whether ST elevation identifies a distinctive abnormality of LV function that might be labeled LV aneurysm, global and regional LV function in 12 patients with QRS patterns of anterior MI and ST elevation were compared with that in 12 patients with similar QRS abnormalities but without ST elevation by means of radionuclide ventriculography. All measured parameters of ventricular function were similar in the 2 groups. ST elevation could not be demonstrated to predict a distinctive abnormality that might be labeled LV aneurysm.
Lattice effects in cuprates

Abstract We describe the fine details of the dependence of the dispersion of the Cu–O bond-stretching phonon in YBa 2 Cu 3 O 6+ x on temperature and composition, recently determined by inelastic neutron scattering. The results suggest the presence of a localized phonon mode above the pseudogap temperature, which softens at lower temperatures. Its implications and possible role in the mechanism of high-temperature superconductivity are discussed.
Biosignal recognition using serial data from a delta modulator

A description is given of circuitry that delta-encodes a biosignal and compares a string of digital features to a reference template. The system was applied to a synthetic ECG (electrocardiogram) waveform. The methodology for developing the templates and the test results are described. >
Simultaneous compensation of previous sample and slope dependent errors in analog to digital converters

Compensation of analog to digital converters (ADCs) has historically been concerned with choosing the dominant error mechanism and then compensating based on the one error mechanism. Compensating on only one error mechanism presents a problem when the dominant error mechanism changes with frequency. This paper presents a way to confront multiple error mechanisms at once and successfully compensate across the full band. Two error mechanisms addressed here are previous sample and signal slope dependent errors. This paper presents a model for error and estimates the error from the harmonics in the spectrum of the calibration signal. The error present in the fundamental component is treated as additional unknowns in the error estimate. Compensation of a simulated ADC resulted in a complete removal of all previous sample and slope dependent error. Hardware results were almost as impressive, showing gains in spurious free dynamic range (SFDR) of up to 17 dB.
Dissociation and hypnosis in post-traumatic stress disorders

After noting the fundamental differences between the agenda of ordinary psychotherapy and the treatment of post-traumatic stress disorder (PTSD), the paper discusses the concept of trauma vis-a-vis PTSD using Yalom's (1981) four existential themes of death, freedom, isolation, and meaninglessness as organizing principles. The middle section of the paper focuses on the role of dissociation in the symptomatology of PTSD, suggesting, among other things, that many PTSD symptoms are dissociative in nature; that it is a defense against both memories of the event and the experience itself. Research is reviewed supporting the connection between PTSD and hypnotizability and the use of hypnosis in treating traumatic stress is discussed followed by two case examples. The latter section focuses on the limitations of hypnosis, transference considerations, and ends with a summary of the author's eight “C's” treatment approach: confront, condensation, confession, consolation, consciousness, concentration, control, and congruence.
Direct Measurement of the Radial Electric Field in Tokamak Plasmas using the Stark Effect

Motional Stark effect polarimetry (MSE) is a well established technique for measuring the magnetic field pitch angle in tokamaks. By viewing the Stark emission spectrum from two different angles, this technique can also provide local measurements of the plasma radial electric field, ${E}_{r}$. Simultaneous measurements of the profiles of magnetic field pitch angle and ${E}_{r}$ are presented for the first time in a high-performance DIII-D tokamak plasma. Direct measurement of ${E}_{r}$ is of great importance in fusion research because the suppression of turbulence through ${\mathbf{E}}_{r}\ifmmode\times\else\texttimes\fi{}\mathbf{B}$ velocity shear provides a mechanism to improve energy confinement.
Developmental regulation of epidermal growth factor receptor kinase in rat intestine

Abstract Background/Aims: Intraluminal epidermal growth factor (EGF) may regulate intestinal growth and function. The ontogeny, localization, and phosphorylation of the EGF receptor in rat small intestine were studied. Methods: EGF-receptor phosphorylation was assayed by antiphosphotyrosine Western blot after EGF administration in vivo and EGF incubation to everted sacs in vitro. EGF-receptor abundance and localization were assayed by Western blot and immunofluorescence using anti-EGF-receptor antibodies. Results: In vivo, orogastric EGF enhanced EGF-receptor phosphorylation in newborn rat jejunum and liver. However, intraluminal EGF had no effect on EGF-receptor phosphorylation in adult intestine or liver. In vitro, mucosal EGF stimulated a fourfold increase in EGF-receptor phosphorylation in suckling jejunum but not in weanling or adult jejunum. In Western blot, EGF-receptor abundance was similar in 22-day-old fetal, 8-day-old suckling, and adult jejunum. In both crypt and villus, EGF-receptor was localized to the basolateral membrane but not to the apical membrane in fetal, suckling, and adult jejunum. Conclusions: Mucosal EGF stimulates EGF-receptor phosphorylation in immature but not in mature intestine. These differences are not explained by EGF-receptor abundance or localization and suggest that the greater mucosal permeability of the immature gut may allow EGF to bind to the EGF-receptor in the basolateral membrane to mediate its effects in suckling rat intestine.
An Optimal Inventory Model for the Intermediate Echelon When Repair is Possible

The basic contribution of the paper is the development of a probabilistic model for computing the optimal purchase, i.e., stockage quantity of an item at an intermediate echelon of supply when repair of the item is possible. For commonly assumed probability distributions of the failure and repair process, it is found that the optimal stockage quantity depends to a large extent on the failure rate and is relatively insensitive to the repair rate. The model is then applied to the problem of determining the extent to which repair is economical at the intermediate echelon. It is concluded that for systems where most items deemed repairable have a low failure rate, the effectiveness of the intermediate echelon may be larger when its primary function is storage rather than repair.