cssi/SciSciGPT-SciSciNet huggingface dataset:
Determination of relative UV response factors for HPLC by use of a chemiluminescent nitrogen-specific detector.

Abstract Ultraviolet (UV) absorbance is the most widely used detection method for high-performance liquid chromatography (HPLC) separations. In pharmaceutical analysis, purity determinations often include quantitation of related impurities based on relative HPLC peak areas obtained at a specific wavelength. In order for this quantitation to accurately reflect weight percentages of impurities, the relative UV response factors (absorptivities) at the given wavelength must be known. In this work, we present a convenient method for determining relative UV response factors on-line, without isolation or purification of impurities, without standards, and without requiring known analyte concentrations. The procedure described makes use of a chemiluminescent nitrogen-specific HPLC detector (CLND) in conjunction with a UV detector. The CLND response is directly proportional to the number of moles of nitrogen in each eluting peak, and can, therefore, be used to determine relative amounts of each nitrogen-containing impurity present in the sample, provided the molecular formulas are known (e.g. from exact mass LC–MS). It is a simple matter, then, to determine the relative UV response factors from the UV area ratios obtained for the same sample. The feasibility and accuracy of this method is demonstrated for gradient HPLC separations of commercially available compounds of widely varying structures. Finally, the method's utility in obtaining accurate mass balance is demonstrated by application to photodegradation of nifedipine.
The mechanism of the middle ear: Part II. The drum

The ear drum is considered to be a thin circular membrane with radial and circular fibers, whose center is pulled inwards by the handle of the hammer. It is shown that such a membrane is equivalent to a rigid piston connected by a lever to the handle of the hammer, and subjected to elastic forces. The stability of the equivalent system is great, and the flexibility of the lever is very small. The lever is such that small pressures in the auditory canal are transformed into larger forces on the hammer. The leverage ratio increases with the tension of the tensor tympani and decreases with the number of circular fibers.
Cardiac deformation indices derived from motion estimated X-ray computed tomography

Cardiac deformation indices such as strain, strain rate, and time to maximal strain are valuable in early detection of heart disease and hold tremendous prognostic value in assessing patients recovering from heart failure. These indices have been previously measured in modalities such as Doppler echocardiography and magnetic resonance imaging. However, cardiac deformation has not been well characterized in X-ray computed tomography (CT), a modality whose balance of high acquisition speed and good temporal and spatial resolution makes it highly desirable in the clinical setting. The current work, an extension of our group’s previously published cardiac motion estimation algorithm, calculates deformation indices such as strain, strain rate, maximum strain, and time to maximal strain from four-dimensional motion vector field data. Along each dimension, calculations are made between every adjacent pair of grid points, thus striving for simplicity while yielding an increase in spatial resolution over approaches that divide the heart into a number of segments. Results are visualized as semi-transparent color maps superimposed on CT image slices in the short-axis view and the two long-axis views. Results agree with the expected behavior of myocardial contraction. Animal studies are underway to better assess the physiologic accuracy of the calculated deformation indices as well as to compare the results with those from other imaging modalities. The present work and its further refinements may yield rich yet easily accessible information for clinicians in early diagnosis and follow-up monitoring.
A computerized approach for determining equal appearing interval attitude scales

The objectives of this brief article are to: (a) report on a method for constructing attitude scales following the equal appearing interval ideas of Thurstone and Chave (1929, pp. 23-58) and (b) discuss a computer program to be used with this method. Thurstone and Chave asked their subjects to sort a large number of statements into 11 piles. In sorting the statements the subjects were asked not to express their own opinions, rather they were asked to judge the degree of favorableness of a statement according to a theoretical scale from 0 to 11. To adapt this procedure to a computer, an IBM 555 response sheet was utilized. This response sheet is unique in that it provides for 10 response categories. Rather than sorting the statements into 11 piles, with a neutral 6th pile, the computerized approach technically eliminates a neutral category, which forces the subject to sort into either Categories 0 through 4 or Categories 5 through 9, resulting in a theoretical neutral category of 4.5. Subjects received a set of instructions which corresponded very closely to the instructions provided by Thurstone and Chave. However, the instructions were oriented toward recording responses on an IBM 555 response sheet. After the IBM 555 response sheets had been completely filled out, they were processed and converted by machine, an IBM 1232 optical pagereader, to an 80-column Hollerith card. Inasmuch as each IBM 555 form has 10 response categories for each of 150 items, and inasmuch as each item is associated with a single column of a Hollerith card, there was a
Plasmon Resonance Absorption In Layered Structures Of Silver With Periodic Corrugation

Plasmon resonance absorption in periodically corrugated layered structures of silver was studied by the photoacoustic method. The layered structures were self-supporting and corrugated with a period of 1888 nm and amplitude varying from 6 to 12 nm, depending on the tnickness. Experimental results of resonance absorption of 633-nm photons were analyzed in terms of the propagation and damping constants of coupled modes of surface plasmons. The coupling efficiency of incident photons to these modes was found to be strongly dependent on corrugation amplitude and layer thickness.
The Treadmill of Production Under NAFTA: Multilateral Trade, Environmental Regulation, and National Sovereignty

The author illustrates the role of NAFTA in the undermining of government attempts to regulate environmental conditions and public health. Two case studies under NAFTA Chapter 11 are examined: (a) Ethyl Corporation v. Canada and (b) Methanex Corporation v. United States. It is argued that multilateral trade agreements have resulted in limiting the power of governmental bodies to regulate their own environmental conditions and that this has been a consequence of two historical processes: (a) the expansion of trade liberalization under free market systems—part of what Schnaiberg calls the “treadmill of production”—and (b) a shift in sovereignty from the nation-state and multinational corporations to consortia of the former two and newly created “supranational organisms”—what Hardt and Negri call “Empire.”
Analytical Calibration Approach to Develop a Seepage Model for the London Avenue Canal Load Test

The U.S. Army Corps of Engineers (USACE) conducted a load test along a portion of the London Avenue Canal as a part of an extensive study following the events of Hurricane Katrina to investigate the performance of I-walls and levees. A 45.7 m (150 ft) long section of the I-wall was hydraulically loaded, and pore pressures and displacements were measured in the vicinity of the I-wall through an extensive instrumentation system. The acquired data were assessed to develop a seepage model that would be applicable to the London Avenue Canal and areas where the soil conditions are similar. Two-dimensional and three-dimensional finite-element seepage analyses were conducted, a parametric study was performed, and a statistical calibration technique was developed to better estimate the actual field conditions in the numerical modeling. Based on this analysis, soil properties and finite-element boundary conditions are recommended for future analyses of the London Avenue Canal and other canals having similar subsurface conditions.
[18F]Fallypride dopamine D2 receptor studies using delayed microPET scans and a modified Logan plot

Abstract [ 18 F]Fallypride PET studies can be used to estimate the nondisplaceable binding potential (BP ND ) in vivo of dopamine D2/D3 receptor-rich regions of the brain. These studies often take considerable time, up to ≥2 h, limiting the throughput. In this work, we investigated whether limited-duration scans performed subsequent to tracer administration yielded stable BP ND estimates. In particular, we applied a modified version of the Logan plot method on the last 60 min of 120-min data and compared the results to those from analysis of the full data set. Methods Fourteen male Sprague-Dawley rats were injected with [ 18 F]fallypride intravenously while under isoflurane anesthesia, and dynamic data were acquired on the microPET Focus 220 scanner for 120 min. The distribution volume ratio (DVR=BP ND +1) was calculated from a Logan plot using 120 min of data and from a modified version using only the last 60 min. Three of these rats were imaged again on a second day to test the reproducibility. A two-tissue compartment model also was used to fit the time–activity curves (TACs) of the 120-min scans to estimate the parameters K 1 , k 2 , k on , k 4 and B max . These parameters were then used to simulate similar TACs while changing k on to reflect changes in the dopaminergic system. The simulated TACs were used as a means for exploring the differences in DVR estimates between the last 60 min only and the full 120 min of simulated data. Results The average DVR from the full 120-min scans was 13.8±0.9, whereas the average DVR estimated from only the last 60 min of data (DVR′) was 16.3±1.0. The DVR estimates showed good reproducibility in the three rats (mean DVR=13.8±1.5 on Day 1 and DVR=13.8±0.9 on Day 2). The simulations showed that the relationship between DVR′ and DVR estimates follows a semilinear form with varying k on . Conclusion Although the BP ND estimates are slightly overestimated in a delayed scan mode (i.e., no initial radiotracer uptake measurements) compared to a full scan, this overestimation depends primarily on k 3 (≈ k on × B max ) and has been evaluated in this work for a wide range of k on values using simulated TACs. In particular, the sensitivity of DVR′ to changes in k on is similar to that of DVR. This method of delayed scans eliminates the necessity of imaging during the initial uptake of the radiotracer and, thus, can be used to increase the throughput of studies.
Numerical Simulation of Steady and Unsteady Compressible Multiphase Flows

The present work concerns the development of an advanced numerical approach to simulate steady and unsteady compressible multiphase flows in the CFD solver FLUENT. Compressible multiphase flows can be simulated under the framework of either the multiphase Mixture/VOF or the Eulerian multifluid model. The governing equations solved are the mixture (Mixture or VOF model) or phase (Eulerian multifluid model) momentum, energy, species transport equations and phase volume fraction equations. Turbulence effects are accounted for using a range of multiphase turbulence models. For the compressible multiphase model, it assumes that only one phase is a compressible gas/gaseous mixture with multiple species. In gas-liquid flows, all the liquid phases can be compressible /incompressible liquid, while in gas-solid flows the solid phase can be treated as a granular flow. To ensure numerical stability and obtain physical solutions, the absolute pressure is limited in a way to satisfy the constraints for both incompressible and compressible flows that may exist in different regions. The compressible effects are taken into account by adding extra terms related to sound speed and phase volume fractions in both the phase volume fraction and the pressure-correction equations. For flow conditions at inlets and exits, only pressure and mass-flow-rate boundaries are applicable. The mixture Mach numbers are defined and used to determine the subsonic or supersonic flows and thermal boundary conditions.The compressible multiphase model have been successfully used to simulate steady and unsteady, sub- and super-sonic compressible multiphase flows in a wide range of 2D and 3D multiphase systems. The examples presented in the paper include: (1). Gas-liquid separation in a vertical cylindrical container; (2). Transient pressure variations in compressible liquid and gas-liquid flows of water hammers; (3). Sub- and super-sonic gas-liquid two-phase flows in a nozzle; (4). Cavitating and ventilated super-cavitating flows; and (5). 3D gas-liquid flows in a three-stream injector. The solver robustness and convergence performance will be discussed. The solutions will be compared with available experimental data or numerical solutions. Emphasis will be focused on the solver performances on simulations of compressible multiphase flows. Overall, the results obtained from the present compressible multiphase model are in line with analytical/CFD solutions or available experimental data. The numerical approach is reasonably fast and robust, and suitable for practical compressible multiphase applications.Copyright © 2012 by ASME
Distribution of survival times in the Fix and Neyman model

In this paper we consider a general illness-death stochastic model in which the transition intensities all vary proportionally to a time function ϕ(t). We extend Chiang's earlier work to include processes which are both reversible and have parameters which are time varying, and obtain survival time distributions and the expectation and variance of survival times.
Critical role of MKP-1 in lipopolysaccharide-induced osteoclast formation through CXCL1 and CXCL2.

Abstract Osteoclast (OC) progenitors (OCP) have been defined in the bone marrow (BM) as CD3 − CD45R(B220) − GR1 − CD11b lo/ − CD115 + (dOCP) and more recently in the peripheral blood (PB) as Lym − Ly6G − CD11b + Ly6C + . These progenitors respond to stimuli, including LPS from periopathogenic Aggregatibacter actinomycetemcomitans , activating MAPK signaling, resulting in cytokine/chemokine-mediated osteoclastogenesis. Intracellular negative signaling pathways, including MAPK phosphatase-1 (MKP-1, gene Dusp1 ) deactivate MAPK pathways (p-p38 and p-JNK) and reduce inflammatory cytokines/chemokines. Objective: To delineate the role of MKP-1 in chemokine-mediated OC formation using defined OC progenitor populations. Given its role in innate immune inflammatory signaling, we hypothesize that MKP-1 regulates LPS-induced OC formation from BM OCP through deregulated chemokines. Methods: BM and PB from WT and Dusp1 −/− female mice (8–12 weeks) was obtained and sorted into defined progenitor populations. BM sorted dOCP were primed with MCSF and RANKL (48 h), blocked with vehicle or chemokine blocking antibodies and stimulated with LPS (48–96 h). TRAP assay and OC activity were measured for OC formation and activity following treatments. NanoString Array and qPCR were utilized for gene expression analysis. Results: Dusp1 −/− dOCPs formed more and larger osteoclasts from CD11b hi and dOCP compared to matched WT ( P Dusp1 −/− mice compared to WT controls. NanoString array data revealed significant deregulation in chemokine expression from Dusp1 −/− versus WT cells. qPCR validation of target genes revealed that Dusp1 deficient CD11b + populations display 1.5–3.5-fold greater expression of CXCL1 and 2–3-fold greater expression of CXCL2 compared to WT in CD11b hi and dOCP ( P Dusp1 −/− cells. Conclusion: MKP-1 negatively regulates chemokine-driven OC formation and subsequent bone resorption in response to LPS stimulation. Collectively, these data provide useful insight into mechanisms potentially leading to the development of therapeutic treatment of periodontal disease.
On the scaling exponent of binary polarization kernels

It is well known that polar coding achieves capacity, but it is so far unknown exactly how fast polar codes approach channel capacity as a function of their blocklength. More precisely, let us fix a binary-input memoryless symmetric channel W of capacity I(W) and a desired probability of error P e . Given W and P e , suppose we wish to communicate at rate I(W) — Δ using a polar code of length n. It has been recently shown that this value of n scales as O (Δ−μ), where the constant μ is known as the scaling exponent. In particular, if W is the binary erasure channel (BEC), then μ = 3.627. This is somewhat disappointing, since random codes achieve the (optimal) scaling exponent μ∗ = 2. As shown by Arikan, channel polarization can be induced via a simple linear transformation: iterated Kronecker product of a 2 × 2 binary matrix G, called the polarization kernel, with itself. Is it possible to improve the scaling exponent of polar codes (on the BEC) if G is replaced by an l × l binary kernel matrix К for some integer l ≥ 3? This is the question we address in the present paper. It was conjectured by Hassani that as l → ∞, a random choice of the polarization kernel К approaches the optimal scaling exponent μ∗ = 2. However, herein, we are primarily interested in small values of l. We begin with the fact that a given l × l polarization kernel К transforms l copies of the underlying channel W into l bit-channels W 1 , W2,…, W l Notably, if W is a BEC with erasure probability z, then each of W 1 , W 2 ,…, W∞ is also a BEC. The erasure probabilities of W 1 , W2,…, W∞ are polynomials in z with integer coefficients and degree at most l. We refer to the corresponding set of polynomials {p 1 (z), p 2 (z),…, p l (z)} as the polarization behavior of K; the scaling exponent of К is completely determined by its polarization behavior. We show that the polarization behavior can be characterized in terms of a nested chain of linear codes: {0} = C 0 ⊂ C 1 ⊂ … ⊂ C l-1 ⊂ C l {0,1}l and use this nested chain of codes to prove that computing the polarization behavior is NP-hard. We further prove that an arbitrary l × l polarization kernel К can be transformed into a lower-triangular form without altering its polarization behavior. We then use this result to answer the following question: what is the smallest value of l for which Arikan's scaling exponent μ(G) = 3.627 can be improved? We show that μ(Κ) ≥ 3.627 for all l × l kernels with l ≤ 7. On the other hand, we explicitly construct an 8 × 8 matrix Kg with μ(Κ g ) = 3.577 (and prove that it is optimal for l ≤ 8). We extend our construction of Kg into a general heuristic design method. Guided by this design method, we employ the coset structure of Reed-Muller codes and bent functions in order to explicitly construct a 16 × 16 kernel K 16 (, with μ(Κ 16 ) = 3.356. We conjecture that this is optimal for l ≤ 16.
Building Preservation: The University of Illinois at Urbana-Champaign’s Stacks Assessment

This article discusses the results of two collection assessments conducted at the University of Illinois at Urbana-Champaign. The library s Preservation Committee completed the first assessment and reported its results in College & Research Libraries in 1989. The second assessment was completed in 2002 and accompanies the institution’s initiative to establish the library’s first centralized preservation and conservation program. Both assessments focused on the central stacks collection, a repository collection serving the institution’s forty-two branch and departmental libraries. Although a reanalysis of the first assessment s data was impossible, the authors attempted to draw comparisons between the two assessments’ results. After thirteen years without a preservation program and without any significant facilities improvements, the results provide insight into the results of deferred collections care and facilities maintenance and offer guidance for conducting similar studies with other research library collections.
Compaction Tests on Aragonitic Sediment: ABSTRACT

Microcrystalline aragonite from the Bahama Banks was compacted in the laboratory at pressures from 10-1 to 105 psi. at room temperature; the effects of heating were explored. The important conditions affecting the maximum compaction were total pressure, rate of loading, rate of removal of water, grain-size, and cohesion of grains. Conditions having a minor effect were initial water content, time period of compaction (for periods of more than 3 hours), and temperature (for water-saturated samples). A new parameter is proposed to characterize compaction: grain proportion (g), which is equal to the volume of grains divided by the bulk volume; g is equal to one minus porosity expressed as a decimal fraction. Grain proportion is a useful index of compaction because it is also the ratio of the dry bulk density to the grain density of the sediment, and thus is a linear measure of the approach to solid rock. The effect of raising the pressure from 1 psi. to 105 psi. on Bahaman aragonitic sediment is to increase the compaction from g = 0.3 to g = 0.8. Rapid loading of the sediment (at 104 psi./min.) results in differential compaction ranging from g = 0.85 under the moving piston to g = 0.65 at the stationary piston; differential compaction also seems to occur at very slow loading rates (10-6 psi./min.). Constricted egress of water as the sediment is compressed can reduce the amount of compaction by ^Dgrg = 0.1. Sediment of 1µ median grain-size compacts to g = 0.5 under 500 psi., but sediment of 200µ median grain-size compacts only to g = 0.4 under the same pressure; furthermore, the compacted coarse sediment falls apart, but the fine sediment is r latively coherent. End_of_Article - Last_Page 633------------
Cognitive Demand of Model Tracing Tutor Tasks: Conceptualizing and Predicting How Deeply Students Engage

Model tracing tutors represent a technology designed to mimic key elements of one-on-one human tutoring. We examine the situations in which such supportive computer technologies may devolve into mindless student work with little conceptual understanding or student development. To analyze the support of student intellectual work in the model tracing tutor case, we adapt a cognitive demand framework that has been previously applied with success to teacher-guided mathematics classrooms. This framework is then tested against think-aloud data from students using a model tracing tutor designed to teach proportional reasoning skills in the context of robotics movement planning problems. Individual tutor tasks are coded for designed level of cognitive demand and compared to students’ enacted level of cognitive demand. In general, designed levels predicted how students enacted the tasks. However, just as in classrooms, student enactment was often at lower levels of demand than designed. Several contextual design features were associated with this decline. Implications for intelligent tutoring system design and research are discussed.
Maximum Likelihood Multichannel Multidimensional Spectrum Estimation

This paper describes the extension of the maximum likelihood spectrum estimation procedure [1] to the multichannel case and compares its properties experimentally with other high resolution methods for multichannel 2-D spectrum analysis [2,3]. The procedure begins with a multichannel optimum filtering problem and extends the original procedure to the estimation of the entire spectral matrix. In so doing it formally encompasses both the original single channel problem and various separate attempts to develop maximum likelihood cross spectral estimates for two random processes [4,5]. The paper also considers the so-called improved maximum likelihood method of Lim and Dowla [6] and develops it for the multichannel case. The methods are applicable to both one-dimensional and multidimensional multichannel spectral estimation.
Boundary of a boundary principle and geometric structure of field theories

We formulate the boundary of a boundary principle, review its applications in electrodynamics, Yang-Mills theory, and general relativity and translate its basic ideas into geometric language. In each of these three theories the density of the source lets itself be constructed-we discover-out of the curvature associated with the field as a Cartan-like moment of this curvature.
Bone Turnover Markers Correlate with Implant fixation in a Rat Model Using LPS Doped Particles to Induced Implant Loosening

Revision surgery for particle-induced implant loosening in total joint replacement is expected to increase dramatically over the next few decades. This study was designed to investigate if local tissue and serum markers of bone remodeling reflect implant fixation following administration of lipopolysaccharide (LPS)-doped polyethylene (PE) particles in a rat model. 24 rats received bilateral implantation of intramedullary titanium rods in the distal femur, followed by weekly bilateral intra-articular injection of either LPS-doped PE particles (n = 12) or vehicle which contained no particles (n= 12) for 12 weeks. The group in which the particles were injected had increased serum C-terminal telopeptide of type I collagen, decreased serum osteocalcin, increased peri-implant eroded surface, decreased peri-implant bone volume, and decreased mechanical pull-out strength compared to the controls. Implant fixation strength was positively correlated with peri-implant bone volume and serum osteocalcin and inversely correlated with serum C-terminal telopeptide of type I collagen, while energy to yield was positively correlated with serum osteocalcin and inversely correlated with the number of tartrate resistant acid phosphatase positive cells at the interface and the amount of peri-implant eroded surface. There was no effect on trabecular bone volume at a remote site. Thus, the particle-induced impaired fixation in this rat model was directly associated with local and serum markers of elevated bone resorption and depressed bone formation, supporting the rationale of exploring both anti-catabolic and anabolic strategies to treat and prevent particle-related implant osteolysis and loosening and indicating that serum markers may prove useful in tracking implant fixation.
New insight into particulate mineral and organic matter in coastal ocean waters through optical inversion

Abstract Suspended particulate inorganic matter (PIM) and particulate organic matter (POM) often exhibit significant variation both spatially and temporally in coastal oceans. The size distributions and optical properties of these particles are poorly known. Utilizing a newly developed inversion technique from the measured angular scattering pattern, we were able to examine POM and PIM in terms of detailed particle size distributions (PSD) and optical volume scattering functions (VSF), gaining further insights and knowledge of particles that will greatly improve biogeochemical investigations and remote-sensing algorithms. We report the results on two extremes or end-members of possible coastal environments, sediment-laden, turbid Mobile Bay, Alabama, USA and biologically productive, clear water Monterey Bay, California, USA. The optically inferred mass concentrations of PIM and POM, when accounting for the fractal nature of suspended particles, agreed well with the respective gravimetric determinations within the analysis and inversion uncertainty. Despite intra- and inter-site variability, the inferred PSDs in both coastal regions commonly showed an apparent background population of PIM at radii 50 μm. The clearly distinctive PSDs between PIM and POM provide evidence to support the Risovic two-component model for suspended particulates. The shape of the VSFs, i.e., the scattering phase functions, for POM are similar between the two sites (backscattering ratio ≈ 0.0015), but the PIM in Monterey Bay exhibited a higher backscattering ratio than in Mobile Bay (backscattering ratios 0.012 vs. 0.008, respectively). At both sites, the mass-specific scattering cross section values for PIM (σ [PIM]) are about 70–80% lower than σ[POM], while the mass-specific backscattering cross section values for PIM (σb[PIM]) are 10–25% greater than σb[POM].
Comparative biology of neotropical epiphytic and saxicolous Tillandsia species : population structure

In comparing the population structure of epiphytic and saxicolous Tillandsia species I found no significant differences between polycarpic species. Epiphytic T. ionochroma populations had a higher seedling:adult ratio than saxicolous T. ionochroma populations, but the difference was not statistically significant. Tillandsia ultriculala , a monocarpic epiphyte, had a significantly higher seedling:adult ratio than the polycarpic species. T. utriculata's higher ratio may result from its greater seed production and lack of vegetative propagation. Unlike the polycarpic species, all adult-size rosettes grow from seeds in T. utriculata. Tillandsia sphaerocephala , an obligate saxicole, occurred in larger clusters (i.e. more rosettes per genet) than T. ionochroma . The increased tendency for vegetative reproduction in T. sphaerocephala suggests that spatial patchiness is less of a constraint than with epiphytes.
Tibial fractures in infants and children: Emphasis on subtle injuries

We present our findings in 175 consecutive infants and children with tibial fractures to demonstrate which of these fractures are most likely to occur, at certain sites in the tibia, and in which age groups. We also demonstrate the most subtle findings seen with each of these fractures and comment on a newly encountered toddler’s fracture involving the upper tibia. Our objective is to alert the imager to reexamine key places in the tibia when no obvious fracture is seen on initial inspection.
Genera of the Torsion-Free Polyhedra

We study the genera of polyhedra (finite cell complexes), i.e., the classes of polyhedra such that all their localizations are stably homotopically equivalent. More precisely, we describe the genera of the torsion-free polyhedra of dimensions not greater than 11. In particular, we find the number of stable homotopy classes in these genera.
Isolation of a Golgi-rich fraction from rat liver

Abstract A fractiion rich is membranes of the Golgi apparatus was isolated from rat liver by discontinuous density gradient centrifugation. Electron microscopic analysis of the fraction revealed the presence of structures very similar to those of the Golgi apparatus in intact cells, namely stacked cisternae, secretory vesicles, and tubular elements. The Golgi-rich fraction contained over 90% of the UDP-galactose; N- acetylglucosamine galactosyltransferase, about 2% of the glucose-6-phosphatase and 12% of the AMP phosphohydrolase present in the post-nuclear supernatant of liver homogenates.
Effect of Molecular Structure on the Electrooptic Performance of Electroclinic Liquid Crystals

Abstract The correlation between molecular structure and electrooptic performance is studied for novel room temperature chiral smectic A liquid crystals. It is observed that slight modifications of the hydrocarbon chain connected to the chiral center result in dramatic differences in their electrooptic performance. If the hydrocarbon chain is shortened or if a double bond is localized at the end of the hydrocarbon chain, the tilt angle, electroclinic coefficient, and switching time are significantly suppressed.
Wood Pellet Co-Firing for Electric Generation Source of Income for Forest Based Low Income Communities in Alabama

Alabama imports coal from other states to generate electricity. This paper assessed the direct and indirect economic impacts of wood pellet production to be co-fired with coal for power generation in Alabama. Four sizes of wood pellet plants and regional input-output models were used for the analysis. The results showed that the economic impact increases with the size of the plant. Wood pellet production will have a multiplier effect on the economy especially, forest-related services, retail stores, the health service industry, and tax revenue for the government. Domestic wood pellet production can reduce the use of imported coal, allow the use of local woody biomass, and create economic activities in Alabama’s rural communities. Policies that support the production of wood pellet will serve to encourage the use of wood for power generation and support the rural economies.
EXCEPTIONAL GROUP RING AUTOMORPHISMS FOR GROUPS OF ORDER 96

An exceptional automorphism is described for a semi-local group ring of a group of order 96. It is argued that there no smaller groups for which exceptional automorphisms exist.
Optically Active Binary Liquid Crystal Thermometry

Research on the biological effects and medical applications of non-ionizing electromagnetic fields often requires the use of nonmetallic non-perturbing temperature sensors. The highly temperature dependent optical activity observed in certain types of liquid crystals makes possible the construction of very sensitive non-perturbing fiberoptic thermometers. A knowledge of the effect of various parameters on the optical rotatory power of the chosen liquid crystal is essential for the construction of such a device. The dependence of the optical rotatory power on temperature, composition, and sample thickness in a binary mixture of a nematic (MBBA) and a cholesteric (Cholesteryl Oleate) liquid crystal was studied. The dependence of effective pitch on composition was determined. Application of the data on rotatory power and effective pitch to the construction of devices is discussed. Illinois under Grant USPHSCA 09067.
Using Linear Combinations of Angle Stacks to Predict Band-limited Porosity And Vshale

We introduce a new type of weighted stack that can be applied to seismic data to produce band-limited estimates of porosity and shale volume (vshale). This weighted stack combines linearized approximations of the seismic reflectivity with linear rock property relationships into a single linear operator that can be applied directly to angle stacks. In order to account for the effects of fluid property variations in the rock property relationships, we specify the location of the fluid contacts within a reservoir and apply rock property relationships appropriate to the fluid at each point in the seismic volume. This method can be useful after an exploration well has been drilled and well logs are available for developing rock property relationships and fluid contact information is available. The method can then be applied to define the distribution of reservoir quality (sands) as part of development planning.
Endoscopic ablation of Barrett's esophagus: a multicenter study with 2.5-year follow-up

Background For patients with Barrett's esophagus (BE), life-long surveillance endoscopy is recommended because of an elevated risk for developing dysplasia and esophageal adenocarcinoma. Various endoscopic therapies have been used to eradicate BE. Recently circumferential radiofrequency ablation has been used with encouraging short-term results. Objective To provide longer follow-up and to assess the long-term safety and efficacy of step-wise circumferential ablation with the addition of focal ablation for BE. Design Prospective, multicenter clinical trial (NCT00489268). Setting Eight U.S. centers, between May 2004 and February 2007. Patients Seventy subjects with 2 to 6 cm of BE and histologic evidence of intestinal metaplasia (IM). Interventions Circumferential ablation was performed at baseline and repeated at 4 months if there was residual IM. Follow-up biopsy specimens were obtained at 1, 3, 6, 12, and 30 months. Specimens were reviewed by a central pathology board. Focal ablation was performed after the 12-month follow-up for histological evidence of IM at the 12-month biopsy (absolute indication) or endoscopic appearance suggestive of columnar-lined esophagus (relative indication). Subjects received esomeprazole for control of esophageal reflux. Main outcome measurements Complete absence of IM per patient from biopsy specimens obtained at 12 and 30 months, defined as complete remission–IM (CR-IM). Results At 12 months, CR-IM was achieved in 48 of 69 available patients (70% per protocol [PP], 69% intention to treat [ITT]). At 30 months after additional focal ablative therapy, CR-IM was achieved in 60 of 61 available patients (98% PP, 97% ITT). There were no strictures or buried glandular mucosa detected by the standardized biopsy protocol at 12 or 30 months, and there were no serious adverse events. Limitations This was an uncontrolled clinical trial with 2.5-year follow-up. Conclusion Stepwise circumferential and focal ablation resulted in complete eradication of IM in 98% of patients at 2.5-year follow-up.
Single photon counting and spectroscopy of low intensity chemiluminescent reactions

With electron multiplier phototubes selected for low dark noise and with direct light coupling, chemiluminescent reactions in solution emitting as little as 200 photons s −1 will produce noise-equivalent counting rates. With this extremely sensitive system it is possible to observe the adventitious chemical production of excited states during the course of oxidase reactions in low intensity chemiluminescence as a tracer for specific metabolic reaction rates. The microsomal metabolism of carcinogenic poly cyclic aromatic hydrocarbons and the bactericidal action of phagocytic cells are accompanied by significant chemiluminescence. In the former, the chemiluminescence emission spectrum has been measured and the mechanism appears to proceed through a dioxetane intermediate to a diradical exciplex. The Luminol chemiluminescent reaction is proposed for the absolute calibration of single photon detectors and for specifying the intrinsic sensitivity of spectrometers. Procedures for these calibrations will be described.
Spontaneous formation of inorganic helices

Attempts to generate films, wires, helices, rings and regular patterns out of inorganic materials1,2,3,4,5,6,7,8,9,10 have been going on for the past 100 years. We show here that stable helices of porous manganese oxide materials can be formed spontaneously from uniform sols and that they are excellent semiconductors. These inorganic helices contain micropores, can be converted into other structures, and their composition can be varied.
Gramicidins A, B, and C form structurally equivalent ion channels.

The membrane structure of the naturally occurring gramicidins A, B, and C was investigated using circular dichroism (CD) spectroscopy and single-channel recording techniques. All three gramicidins form channels with fairly similar properties (Bamberg, E., K. Noda, E. Gross, and P. Lauger. 1976. Biochim. Biophys. Acta. 419:223–228.). When incorporated into lysophosphatidylcholine micelles, however, the CD spectrum of gramicidin B is different from that of gramicidin A or C (cf. Prasad, K. U., T. L. Trapane, D. Busath, G. Szabo, and D. W. Urry. 1983. Int. J. Pept. Protein Res. 22:341–347.). The structural identity of the channels formed by gramicidin B has, therefore, been uncertain. We find that when gramicidins A and B are incorporated into dipalmitoylphosphatidylcholine vesicles, their CD spectra are fairly similar, suggesting that the two channel structures could be similar. In planar bilayers, gramicidins A, B, and C all form hybrid channels with each other. The properties of the hybrid channels are intermediate to those of the symmetric channels, and the appearance rates of the hybrid channels (relative to the symmetric channels) corresponds to what would be predicted if all three gramicidin molecules were to form structurally equivalent channels. These results allow us to interpret the different behavior of channels formed by the three gramicidins solely on the basis of the amino acid substitution at position 11.
A three-stage algorithm to make toxicologically relevant activity calls from quantitative high throughput screening data.

Background: The ability of a substance to induce a toxicological response is better understood by analyzing the response profile over a broad range of concentrations than at a single concentration....
Wheat Vegetative Nitrogen Compositional Changes in Response to Reduced Reproductive Sink Strength

N redistribution patterns and the N composition of vegetative tissues above the peduncle node of wheat (Triticum aestivum L.) plants with altered reproductive sink strength were evaluated to determine the role of vegetative storage proteins in the temporary storage of excess N destined for export. The degree of leaf senescence symptoms (loss of chlorophyll, total N, and ribulose-1,5-bisphosphate carboxylase/oxygenase) were initially reduced, but the complete senescence of vegetative tissues proceeded even for plants completely lacking reproductive sinks. Plants with 50% less sink strength than control plants with intact spikes redistributed vegetative N to the spike almost as effectively as the control plants. Plants without reproductive sinks exported less N from the flag leaf and had flag leaf blades and peduncle tissues with higher soluble protein and α-NH2 amino acid levels than control plants. An abundant accumulation of polypeptides in the soluble protein profiles of vegetative tissues was not evident in plants with reduced sink strength. Storage of amino acids apparently accommodates any excess N accumulated by vegetative tissues during tissue reproductive growth. Any significant role of vegetative storage proteins in the N economy of wheat is unlikely.
Nerve growth factor in mouse milk during early lactation: lack of dependency on submandibular salivary glands.

ABSTRACT: Using a specific and sensitive nerve growth factor radioimmunoassay we show measurable quantities of β nerve growth factor in mouse milk during the period of early lactation. Partial purification by cationic exchange resin yielded a preparation which exhibited biological activity in a PC-12 cell bioassay system. Submandibularsublingual sialoadenectomy had no influence on the breast milk NGF concentrations. These results support the presence of bioactive NGF in mouse milk during early lactation, but do not clarify the source.
Colon cancer knowledge and attitudes in an immigrant Haitian community.

Objective To qualitatively evaluate the views of Haitian immigrants on cancer and the influence of cultural and socio-ecological factors on cancer screening behavior. Methods Six focus groups, consisting of 4–10 individuals each, were conducted among Haitian adults at average risk for colorectal cancer. The interviews were conducted in Haitian Creole and featured questions that addressed beliefs and attitudes about general health, access to health care, colon cancer, and screening practices. Results The focus groups provided insight into the health service utilization patterns in the Haitian community, as well as the factors driving them including language and the pattern of accessing healthcare only for emergencies. Conclusions Many misconceptions regarding cancer and its development were evident in the discussions. However participants were willing to follow the recommendations of a physician. This highlighted the importance in this community of disseminating information at every opportunity about preventative care, including colorectal cancer screening.
Issues of Access and Usability in Designing Digital Resources for Children

Abstract The way children's cognitive states affect how they function in digital interfaces is examined through articles published between 1989 and 2010. Children have developmental limitations, such as underdeveloped motor skills, difficulties with spelling, and trouble understanding hierarchies, classification schemes, and metadata, that make it difficult for them to find information, and challenging for adult designers to accommodate their needs. From icons to metadata to hierarchies, the best research in designing digital resources for children, (OPACs such as Pejtersen's Book House, online public libraries such as the Internet Public Library, and online collections of books such as the International Children's Digital Library), places the child user at the center, and takes an interdisciplinary and intergenerational approach. The literature indicates that research in designing for children is valuable, not only because it seeks to improve children's experience with digital resources, but also because such research translates to other marginalized users and special needs populations.
Interaction Coherence Analysis for Dark Web Forums

Interaction coherence analysis (ICA) attempts to accurately identify and construct interaction networks by using various features and techniques. It is useful to identify user roles, user's social and information value, as well as the social network structure of Dark Web communities. In this study, we applied interaction coherence analysis for Dark Web forums using the hybrid interaction coherence (HIC) algorithm. Our algorithm utilizes both system features such as header information and quotations, and linguistic features such as direct address and lexical relation. Furthermore, several similarity-based methods, for example vector space model, dice equation, and sliding window, are used to address various types of noises. Two experiments have been conducted to compare our HIC algorithm with traditional linkage-based method, similarity-based method, and a simplified HIC method that does not address noise issues. The results demonstrate the effectiveness of our HIC algorithm for identifying interactions in Dark Web forums.
Carbohydrate Deficient Transferrin in Abstaining Patients With End‐Stage Liver Disease

Over two decades ago, the identification of carbohydrate deficient (desialylated) transferrin (CDT) and its association with alcohol consumption (Stibler, 1979) captured the interest of clinicians and researchers alike. As a biochemical marker of chronic alcohol use, an elevated CDT could potentially aid in the detection and monitoring of patients with heavy alcohol consumption. Compared to liver enzyme profiles, CDT can have superior sensitivity in detecting alcohol abuse (Litten 1995, Anton 1994). While the clinical utility of CDT is being explored in a variety of settings, concerns over the impact of various disease states on CDT values have been raised. In particular, because CDT is synthesized, glycosylated, and secreted by the liver, the use of CDT values in patients with liver disease has been an area of focused interest. The earliest work in this area investigated the correlations between various biochemical liver tests, biopsy-verified liver disease and CDT values in patients with liver disease and found that liver disease without current alcohol use was not associated with elevated CDT (Stibler, 1987). However, while the degree of liver fibrosis did not correlate with elevated CDT levels, in that study few patients had advanced liver disease (cirrhosis) and only 10% were clinically affected by their liver disease (Stibler, 1987). In contrast, investigations of other specific populations have reported a high degree of variability in CDT depending on body iron (DeFeo, 1999), gender and exogenous estrogens (Stauber, 1996), and specific types of liver diseases (Murawaki, 1997; Bell, 1993, Stauber, 1995). For example, Heinemann found an unacceptable specificity rate (as low as 20 - 50%) resulting in a high rate of false positives in patients with severe liver disease awaiting liver transplantation (Heinemann, 1998). We are interested in using CDT values to follow patients’ alcohol consumption before and after liver transplantation, specifically for patients with alcoholic cirrhosis. However, given that many of our patients have serious liver disease, we were concerned about the potential poor specificity of CDT values in such patients. Therefore we investigated the impact of the degree of liver disease on CDT values in the absence of alcohol consumption. Our patients all have end-stage liver disease with the majority of patients having non-alcoholic liver disease. In these abstaining patients, the CDT values are expected to be normal. Nevertheless, we hypothesized that while mild to moderate liver insufficiency may not affect CDT values (as seen in prior studies), in our patients, with advanced liver disease, CDT values may be elevated reflecting the degree of liver failure rather than alcohol consumption.