cssi/SciSciGPT-SciSciNet huggingface dataset:
Cortical actin filaments fragment and aggregate to form chloroplast-associated and free F-actin rings in mechanically isolated Zinnia mesophyll cells

Changes in F-actin organization following mechanical isolation ofZinnia mesophyll cells were documented by rhodamine-phalloidin staining. Immediately after isolation, most cells contained irregular cortical actin fragments of varying lengths, and less than 5% of cells contained intact cortical filaments. During the first 8 h of culture, filament fragments were replaced by actin rings, stellate actin aggregates, and bundled filament fragments. Some of these aggregates had no association with organelles (“free” actin aggregates). Other aggregates were associated with chloroplasts, which changed in shape and location at the same time actin aggregates appeared. F-actin was concentrated within or around the nucleus in a small percentage of cells. After 12 h in culture, the percentage of cells with free actin rings and chloroplast-associated actin aggregates began to decline and the percentage of cells having intact cortical actin filaments increased greatly. Intermediate images were recorded that strongly indicate that free actin rings, chloroplast-associated actin rings, and other actin aggregates self-assemble by successive bundling of actin filament fragments. The fragmentation and bundling of F-actin observed in mechanically isolatedZinnia cells resembles changes in F-actin distribution reported after diverse forms of cell disturbance and appears to be an example of a generalized response of the actin cytoskeleton to cell stress.
Tryptophan as a probe of photosystem I electron transfer reactions: a UV resonance Raman study.

Photosystem I (PSI) is one of the two membrane-associated reaction centers involved in oxygenic photosynthesis. In photosynthesis, solar energy is converted to chemical energy in the form of a transmembrane charge separation. PSI oxidizes cytochrome c6 or plastocyanin and reduces ferredoxin. In cyanobacterial PSI, there are 10 tryptophan residues with indole side chains located less than 10 A from the electron transfer cofactors. In this study, we apply pump−probe difference UV resonance Raman (UVRR) spectroscopy to acquire the spectrum of aromatic amino acids in cyanobacterial PSI. This UVRR technique allows the use of the tryptophan vibrational spectrum as a reporter for structural changes, which are linked to PSI electron transfer reactions. Our results show that photo-oxidation of the chlorophyll a/a′ heterodimer, P700, causes shifts in the vibrational frequencies of two or more tryptophan residues. Similar perturbations of tryptophan are observed when P700 is chemically oxidized. The observed spectra...
Information capacity and innovation adoption

Researchers of innovation adoption and diffusion often have tested the hypothesis that firms with greater capacities to gather and evaluate information should adopt sooner. However, the data generally do not support this hypothesis. A theoretical model of innovation adoption under uncertainty is developed to show that greater information capacity implies not only faster learning, which tends to reduce the expected delay until adoption, but also a more stringent adoption criterion, which tends to increase the expected delay. The resulting ambiguity provides an explanation for the lack of empirical support for this hypothesis.
Myopia and corrective lenses

Abstract The Biological Theory of spherical error of refraction implies that the use of a corrective lensfor myopia will not aggravate myopia. The Biological Theory is the currently accepted theory among ophthalmologists and optomerists. The Use-Abuse Theory predicts that use of a corrective lens for myopia in near vision will aggravate myopia. This paper tests for such an aggravating effect. Data from a panel of children and youths in the U.S. are examined. The use of a corrective lens for myopia is found to increase a child's myopia, net of relevant control variables.
Impact of Clostridium difficile colitis following closure of a diverting loop ileostomy: results of a matched cohort study.

Aim Previous reports describing Clostridium difficile colitis (CDC) developing after the closure of a loop ileostomy suggest it is severe. In this study the incidence of CDC following ileostomy closure and its effect on the postoperative outcome have been studied. Method Patients undergoing closure of loop ileostomy from 2004 to 2008 were analysed using the Nationwide Inpatient Sample. Patients who developed postoperative CDC (n = 217) were matched 10:1 to a propensityscore-matched cohort of patients without CDC (n = 13 245). Linear and logistic regression were used to examine the effect of CDC on hospital cost (US dollars), length of stay and mortality rates. Population resampling was performed using nearest neighbour bootstrapping to confirm the validity of the results. Results The incidence of CDC following ileostomy closure was 16 per 1000 patients. The mean length of stay was 11.5 days longer among CDC patients (P < 0.0001), with a greater cost of hospitalization of US$21 240 (P < 0.0001). There was no difference in mortality between the cohorts. Conclusion CDC following ileostomy closure is an uncommon, costly and morbid complication. Patients undergoing stoma closure are at high risk for an adverse outcome if they have CDC. Should it develop they should be aggressively treated.
Voxel-based dose reconstruction for total body irradiation with helical tomotherapy.

Purpose We have developed a megavoltage CT (MVCT)-based dose reconstruction strategy for total body irradiation (TBI) with helical TomoTherapy (HT) using a deformable registration model to account for the patient’s interfraction changes. The proposed technique serves as an efficient tool for delivered dose verification and, potentially, plan adaptation. Methods and Materials Four patients with acute myelogenous leukemia treated with TBI using HT were selected for this study. The prescription was 12 Gy, 2 Gy/fraction, twice per day, given at least 6 h apart. The original plan achieved coverage of 80% of the clinical target volume (CTV) by the 12 Gy isodose surface. MVCTs were acquired prior to each treatment. Regions of interest were contoured on each MVCT. The dose for each fraction was calculated based on the MVCT using the HT planned adaptive station. B-spline deformable registration was conducted to establish voxel-to-voxel correspondence between the MVCT and the planning CT. The resultant deformation vector was employed to map the reconstructed dose from each fraction to the same point as the plan dose, and a voxel-to-voxel summed dose from all six fractions was obtained. The reconstructed dose distribution and its dosimetric parameters were compared with those of the original treatment plan. Results While changes in CTV contours occurred in all patients, the reconstructed dose distribution showed that the dose-volume histogram for CTV coverage was close ( Conclusion Voxel-based dose reconstruction strategy that takes into account interfraction anatomical changes using MVCTs is a powerful tool for treatment verification of the delivered doses. This proposed technique can also be applied to adaptive TBI therapy using HT.
Metallic Mineral Resources in the Twenty-First Century. I. Historical Extraction Trends and Expected Demand

Industrial, technological, and economic developments depend on the availability of metallic raw materials. As a greater fraction of the Earth’s population has become part of developed economies and as developed societies have become more affluent, the demand on metallic mineral resources has increased. Yet metallic minerals are non-renewable natural resources, the supply of which, even if unknown and potentially large, is finite. An analysis of historical extraction trends for eighteen metals, going back to the year 1900, demonstrates that demand of metallic raw materials has increased as a result of both increase in world population and increase in per-capita consumption. These eighteen metals can be arranged into four distinct groups, for each of which it is possible to identify a consistent pattern of per-capita demand as a function of time. These patterns can, in turn, be explained in terms of the industrial and technological applications, and in some cases conventional uses as well, of the metals in each group. Under the assumption that these patterns will continue into the future, and that world population will grow by no more than about 50% by the year 2100, one can estimate the amount of metallic raw materials that will be required to sustain the world’s economy throughout the twenty-first century. From the present until the year 2100, the world can be expected to require about one order of magnitude more metal than the total amount of metal that fueled technological and economic growth between the age of steam and the present day. For most of the metals considered here, this corresponds to 5–10 times the amount of metal contained in proven ore reserves. The two chief driving factors of this expected demand are growth in per-capita consumption and present-day absolute population numbers. World population is already so large that additional population growth makes only a small contribution to the expected future demand of metallic raw materials. It is not known whether or not the amount of metal required to sustain the world’s economy throughout this century exists in exploitable mineral resources. In the accompanying paper, I show that it is nevertheless possible to make statistical inferences about the size distribution of the mineral deposits that will need to be discovered and developed in order to satisfy the expected demand. Those results neither prove nor disprove that the needed resources exist but can be used to improve our understanding of the challenges facing future supply of metallic raw materials.
The dosimetric properties of an intraoperative radiation therapy applicator system for a Mevatron-80

An applicator system for intraoperative radiation therapy has been fabricated which does not require physical docking with the accelerator. A dosimetric study has been completed which documents the properties of this system for a variety of electron beam energies, applicator sizes, collimator settings, both primary and secondary, and source-surface distance (SSD) settings. Sensitivity of the system to common misalignment errors was also determined. Results indicate (a) applicator leakage of less than 5%, (b) beam flatness to within plus or minus 5% at the dMAX with a single primary collimator setting, (c) smooth changes in output with cone size, beam energy and SSD, and (d) negligible changes in dose distributions within alignment errors permitted by the system.
Assimilation of Freeze - Thaw Observations into the NASA Catchment Land Surface Model

AbstractThe land surface freeze–thaw (F/T) state plays a key role in the hydrological and carbon cycles and thus affects water and energy exchanges and vegetation productivity at the land surface. In this study, an F/T assimilation algorithm was developed for the NASA Goddard Earth Observing System, version 5 (GEOS-5), modeling and assimilation framework. The algorithm includes a newly developed observation operator that diagnoses the landscape F/T state in the GEOS-5 Catchment land surface model. The F/T analysis is a rule-based approach that adjusts Catchment model state variables in response to binary F/T observations, while also considering forecast and observation errors. A regional observing system simulation experiment was conducted using synthetically generated F/T observations. The assimilation of perfect (error free) F/T observations reduced the root-mean-square errors (RMSEs) of surface temperature and soil temperature by 0.206° and 0.061°C, respectively, when compared to model estimates (equiv...
Methodology for estimating burned area from AVHRR reflectance data

Abstract Two methods are described to determine burned area from Advanced Very High Resolution Radiometer (AVHRR) data. The first method, or the “linear method”, employs Channel 2 reflectance, R2, and is based on the nearly linear relationship between the fraction of pixel burned, P, and R2. The second method, or the “nonlinear method”, employs the Normalized Difference Vegetation Index (NDVI) derived from Channels 1 and 2 reflectances, and is based on the nonlinear relationship P = f(NDVI), a polynomial of order 2 in NDVI. The coefficients of the polynomial are parameterized as a function of the NDVI of the background before the fire event. Radiative transfer simulations indicate that the linear method, unlike the nonlinear method, must be applied to top-of-atmosphere reflectances that have been corrected for atmospheric influence. Sensitivity studies suggest that the methods are subject to some limitations. To avoid discontinuity problems, the original background (just before the fire) must be characterized by a Channel 2 reflectance above 0.07 and by a positive NDVI. To separate the useful signal from atmospheric effects, the fire scar must occupy at least 20% and 12% of the pixel area in the case of savanna and green vegetation (e.g., forest), respectively. When applied to uniform pixels, the mean relative error on the fraction of area burned is about 20% for the linear method and 10% for the nonlinear method. The linear method gives better results for nonuniform pixels, but neither method can be used when the pixel contains low reflectance backgrounds (e.g., water).
Patterns of immune responses evoked by allogeneic hepatocytes: Evidence for independent co-dominant roles for CD4+ and CD8+ T-cell responses in acute rejection

Introduction. This is the first in a series of reports that characterizes immune responses evoked by allogeneic hepatocytes using a functional model of hepatocyte transplantation in mice. Methods. Donor hepatocytes expressing the transgene human alpha-1-antitrypsin (hA1AT-FVB/N, H2 q ) were transplanted into C57BL/6 (H2 b ) or MHC II knockout (H2 b ) hosts treated with anti-CD4, anti-CD8, or a combination of anti-CD4 and anti-CD8 monoclonal antibodies (mAbs). Hepatocyte rejection was determined as a loss of circulating ELISA-detectable transgene product (hA1AT). In addition, some C57BL/6 mice underwent transplantation with FVB/N heterotopic cardiac allografts and were treated with anti-CD4 mAb. Cardiac allograft rejection was determined by palpation. Graft recipients were tested for donor-reactive alloantibodies and donor-reactive delayed-type hypersensitivity (DTH) responses. Results. The median survival time (MST) of allogeneic hepatocytes in normal C57BL/6 mice was 10 days (no treatment), 10 days (anti-CD4 mAb), 14 days (anti-CD8 mAb), and 35 days (anti-CD4 and anti-CD8 mAbs). The MST of hepatocytes in B6 MHC class II knockout mice was 10 days (no treatment) and 21 days (anti-CD8 mAb). The MST of cardiac allografts was 11 days (no treatment) and >100 days (anti-CD4 mAb). Donor-reactive DTH responses were readily detected in both untreated and mAb-treated recipients. Donor-reactive alloantibody was barely detectable in untreated hosts. Conclusions. These studies demonstrate that allogeneic hepatocytes are highly immunogenic and stimulate strong cell-mediated immune responses by both CD4 + and CD8 + T cells, even when treated with agents that can cause acceptance of cardiac allografts. Indeed, CD4 + or CD8 + T cells seem to independently cause hepatocellular allograft rejection. Allogeneic hepatocytes evoked strong donor-reactive DTH responses but were poor stimuli for donor-reactive antibody production. This is an unusual pattern of immune reactivity in allograft recipients.
Some remarks on damage theory

Abstract To date, damage theory suffers from both the lack of uniformity in its approach and the lack of rigor in its developments. It is one of the aims of this paper to somewhat remedy the second inconvenience and to show that, in turn, rigor greatly helps selecting prevailing points of view. This programme is carried out for the broad problem of anisotropic damage, and general directions for future research in various areas are indicated. In addition, in the case of isotropic damage, we have been able to establish a model that does not exhibit the weaknesses of the usual generalization of Kachanov's theory. In particular, softening of the material is translated by the modifications of both Young's modulus and Poisson's ratio, the change in volume due to voids expansion is properly accounted for, and the need for empirically determined thresholds for failure is eliminated. The model is valid for both the quasi-static and dynamic cases, in the assumption of small elasto-plastic deformations but without restriction to small damage. For simplicity, attention is confined to isothermal processes. The model is well suited for the mathematical treatment of PDEs. The final section is indeed devoted to some theoretical existence and uniqueness results.
Measurement of Plasma Colloid Osmotic Pressure in Normal Thoroughbred Neonatal Foals

A normal plasma colloid osmotic pressure (COP) interval was established for foals and compared to values for adult horses. Plasma samples were obtained from 38 Thoroughbred foals that had normal findings on postfoaling examination and 10 healthy Thoroughbred adult horses. Samples were analyzed using a commercially available colloid osmometer. Fifty samples were obtained from 38 foals. Twelve foals had 2 samples taken, 1 during the 1st 24 hours of life and the 2nd between 24 and 72 hours of life. For foals with 2 samples, only 1 randomly selected value was used in group analysis. Total plasma protein, albumin, and globulin concentrations were measured on all samples from foals. The mean measured plasma COP for foals was 18.8 +/- 1.9 mm Hg for the 38 samples analyzed. Measured plasma COP did not differ significantly over the time period examined for either the 12 paired samples (P = .13) or with regression analysis of the 38 samples (P = .13). Calculation of mean COP, based on previously published quadratic equations using total protein, albumin, and globulin concentrations, underestimated mean measured foal COP values except for when total protein measured by refractometer was used in the Landis-Pappenheimer equation. In conclusion, the plasma COP interval (95% CI: 15.0 mm Hg, 22.6 mm Hg) obtained for healthy foals in this study was found to be lower than that of healthy adult Thoroughbreds (20.6 +/- 0.7 mm Hg, P = .006).
Tin and iron hydrous oxide deposits on polyethylene, teflon, and paraffin

Abstract Colloidal particles from tin and iron hydrous oxide colloids have been deposited on hydrophobic surfaces, rendering the surfaces hydrophilic. Advancing and receding contact angles were measured on untreated and colloid-treated polyethylene and Teflon to characterize the transition from nonwetting to wetting. A hydrosol of tin and one of iron was characterized by pH, surface tension, immersion time necessary to convert polyethylene and Teflon to hydrophilic surfaces, amount of deposited colloid, electron micrographs, and diffraction patterns.
The proteins in membrane and cytoplasmic ribosomes of Streptococcus fecalis. An extra protein in the 50-S subparticles of cytoplasmic ribosomes.

Abstract 1. 1.|The existence of both membrane-associated and cytoplasmic ribosomes in Streptococcus fecalis prompted us to investigate whether or not they are identical. Ribosomes were isolated from the cytoplasmic and membrane fractions of Streptococcus fecalis (ATCC No. 9790). When compared in the analytical ultracentrifuge, the two sets of ribosomes were indistinguishable and consisted of about a 1:1 mixture of 52- and 33-S subparticles. The proteins from both sets of ribosomes were extracted with acetic acid and were compared by electrophoresis at pH 4.2 in slabs of polyacrylamide gel containing 7.5 M urea. The electrophoretic pattern of the protein of the 52-S subparticles usually contains about 17 major bands while that of the 33-S subparticles contains about 14 major bands. 2. 2.|Although there was general similarity between the electrophoretic patterns of the total ribosomal proteins, the cytoplasmic ribosomes consistently contained a protein which is absent from membrane ribosomes. Analysis of the proteins extracted from the 52- and 33-S subparticles reveals that the extra protein in the cytoplasmic ribosomes belongs exclusively to the 52-S subparticle. Since the extra protein was not detected in the membrane 52-S subparticles or in any nonribosomal cell fraction, we have designated it as the C50-X protein. 3. 3.|The C50-X protein was extracted from cytoplasmic ribosomes using NH4Cl between 0.5 and 1.0 M; it was then purified by electrofocusing in the presence of 6 M urea. The C50-X protein has an isoelectric point of 5.9 and appears to be a single polypeptide chain. Electrophoretic analysis in polyacrylamide gels containing 0.1% sodium dodecyl sulfate indicates that the C50-X protein has a molecular weight of approx. 45 000. 4. 4.|These results indicate that the membrane and cytoplasmic ribosomes isolated from Streptococcus fecalis are not completely identical with respect to the protein components in the 50-S subparticle.
JADD Announcements for August 2008

May 9–10, 2009 The 12th Annual Meeting of the Infantile Seizure Society (ISS): International Symposium on Epilepsy in Autistic Spectrum Disorders and Related Conditions (ISEASD) Kurume, Japan Chairperson of ISS: Yukio Fukuyama President of ISEASD: Toyojiro Matsuishi Email: iss2009@med.kurume-u.ac.jp URL: http://www.med.kurume-u.ac.jp/med/ped/iss2009/ index.html URL: http://www.iss-jpn.info/ If you would like more information, please contact the secretary of ISEASD (Yushiro Yamashita, email: iss2009@ med.kurume-u.ac.jp).
Synergy of NMR, Computation, and X-Ray Crystallography for Structural Biology

NMR spectroscopy and X-ray crystallography are currently the two most widely applied methods for the determination of macromolecular structures at high resolution. More recently, significant advances have been made in algorithms for the de novo prediction of protein structure, and, in favorable cases, the predicted models agree extremely well with experimentally determined structures. Here, we demonstrate a synergistic combination of NMR spectroscopy, de novo structure prediction, and X-ray crystallography in an effective overall strategy for rapidly determining the structure of the coat protein C-terminal domain from the Sulfolobus islandicus rod-shaped virus (SIRV). This approach takes advantage of the most accessible aspects of each structural technique and may be widely applicable for structure determination.
Corneal deturgescence during organ culture.

A simple method is described to monitor rabbit and human corneal deturgescence while the tissue is suspended in tissue culture media. The composition of the media is such that the cornea slowly thickens at 4° but exhibits the classic “temperature reversal” thinning phenomenon when incubated at 23°-37°. Each cornea is cultured in a closed eye bank corneal viewing chamber during swelling and deswelling phases of an experiment, minimizing direct handling of the tissue. Optimal conditions for observing corneal deturgescence are described. This protocol has several advantages over corneal perfusion techniques and could be further developed for routine use in eye banks as a functional test of donor suitability for keratoplasty.
Suboptimal policy determination for large-scale Markov decision processes, part 2: Implementation and numerical evaluation

We present an implementation of the procedure for determining a suboptimal policy for a large-scale Markov decision process (MDP) presented in Part 1. An operation count analysis illuminates the significant computational benefits of this procedure for determining an optimal policy relative to a procedure for determining a suboptimal policy based on state and action space aggregation. Results of a preliminary numerical study indicate that the quality of the suboptimal policy produced by the 3MDP approach shows promise.
The New Economic History and the Burdens of the Navigation Acts

AT a recent meeting of the American Economic Association, Peter McClelland presented a paper on the economic costs to America of British imperial policy.2 An important part of his paper is the sharply worded criticism of the studies by Harper3 and Thomas.4 McClelland attempts to "show that the conceptual framework of both Thomas and Harper is so defective that their final results were virtually meaningless",5 and he offers "an alternative upper-bound measure of the cost to America of the British Acts of Trade".6 Harper must have received somewhat uneasily the news that much of his life's work is virtually meaningless. Fortunately for him, Jonathan Hughes, one of the discussants at the economic history session, eloquently and persuasively defended Harper's conclusions.7 Unfortunately for Thomas, a similar voice on his behalf was not heard; likewise for McClelland, much doubt was expressed about the positive contribution of his alternative upper-bound measure. As Hughes expressed it, "I'm glad we made the trip, but we could have stayed home comfortably with Lawrence Harper,"8 and Herman Krooss, the other discussant, added: "Since before Beer and after Harper, historians and economists of great talent
Numerical simulation of a thermally stratified shear layer using the vortex element method

Abstract In computing the development of an unstable inviscid shear layer, it is found that using a fixed number of vortex elements can lead to large errors due to the strong strain field which develops and acts to distort the original vorticity contours. It is suggested that the vorticity should be redistributed among elements which are arranged in the local: principal direction of strain in order to capture this distortion accurately. Mixing within an initially stratified layer, which results from the combined action of convection and diffusion, is computed using a similar scheme to integrate the energy equation. Calculations illustrate the evolution of the temperature profile during the growth of the instability.
The effect of health improvements due to tobacco control on earnings in the United States

There is minimal evidence causally estimating the relationship between tobacco tax policy, population health and earnings. This article uses state tobacco taxes as an instrument for life expectancy to estimate the effect on earnings per capita in a panel of almost 3000 counties in the United States over the period 1970 to 2000. In the first stage of the model, we find that a one dollar increase in state tobacco taxes significantly increases life expectancy between 1.9% and 2.1%. Despite showing that tobacco tax is correlated with higher life expectancy and that, theoretically, improvements in health from reductions in smoking should lead to increased earnings, we find an insignificant impact of the induced gains in life expectancy from tobacco policy on county level earnings per capita over the period 1970 to 2000. The lack of significance is explained through local average treatment effects and the smaller economic impact of certain policies that impact health later in life. These results provide further...
Studies on the manganese requirement of fingerling channel catfish

Abstract Fingerling channel catfish ( Ictalurus punctatus ) were fed purified diets containing varying levels of manganese for 13 weeks in two experiments. Weight gain and feed efficiency data of catfish fed the basal diet (2.4 mg Mn/kg diet) were not significantly different from those of catfish fed manganese-supplemented diets in both experiments. Liver manganese superoxide dismutase activity, liver manganese concentration, serum alkaline phosphatase activity and hexosamine content of gill filament cartilage did not differ in catfish fed basal and manganese-supplemented diets. Bone manganese concentration increased almost linearly with increasing dietary manganese levels. The 2.4 mg Mn/kg supplied by the basal diet was apparently sufficient to meet the manganese requirement of fingerling channel catfish during these experiments.
Attenuation Tomography of the Earth’s Mantle: A Review of Current Status

Resolving the lateral variations of attenuation in the deep mantle by tomographic methods holds potential for constraining its thermal structure and dynamics. It is a challenging subject which has been addressed by only a few studies until now. We here review the main motivations behind pursuing this challenge, the difficult issues involved in separating effects of anelastic attenuation from scattering and focusing due to propagation in 3-D elastic structure and finally discuss the current status of global attenuation tomography.
Rational design of contact guiding, neurotrophic matrices for peripheral nerve regeneration.

Nerve guides filled with magnetically aligned hydrated gels of type I collagen have been shown to impart strong contact guidance cues to elongating neurites in vitro 15 and to increase the number of regenerating axons in vivo 8 relative to an isotropic collagen gel. We have formulated and analyzed a model to determine the conditions under which the target concentration of nerve growth factor (NGF) to support axonal growth can be sustained by entrapping either NGF-secreting cells or NGF-releasing polymer microspheres in the aligned gel. The equation describing NGF concentration with a distributed source term was solved after experimental determination of (1) the rate of NGF release from PLGA 85/15 microspheres, (2) the NGF diffusion coefficient in the gel and nerve guide membrane containing the gel, and (3) the maximum microsphere loading that does not compromise the magnetic alignment of collagen fibrils. We find that for a rat sciatic nerve, when using a 1 mm diameter nerve guide within a commercially available collagen membrane, the microsphere loading limit will prevent the construct's capacity to sustain the target NGF concentration of 1 ng/ml at two months when either wild type Schwann cells or PLGA 85/15 microspheres are used as the NGF source. This target concentration, however, will be maintained when transfected cells described in the literature to hypersecrete NGF are used, or when the microspheres are used if the permeability of the nerve guide membrane can be moderately decreased. For a human median nerve, when using a 5 mm diameter nerve guide within a commercially available membrane, the microspheres are capable of sustaining NGF concentrations above 1 ng/ml to at least 75 days without the need to decrease membrane permeability. © 2003 Biomedical Engineering Society. PAC2003: 8780Xa, 8718Sn, 8715Vv
Generation of streamwise vortical structures in bluff body wakes.

Direct numerical simulation is used to study the periodic generation and evolution of streamwise vortical structures in the near wake of a circular cylinder. It is observed that streamwise structures are formed due to stretching of core vorticity which escapes out of the core and due to stretching of small scale streamwise vorticity already present outside the core. Distinct hairpin structures are observed which play a central role in transferring vorticity out of the core. Furthermore, the hairpin structures are associated with a spanwise subharmonic mode and are thus manifestations of a period-doubling mechanism.
Chert in the Pacific: Biogenic silica and hydrothermal circulation

Abstract Data on sections drilled by DSDP and ODP in the Pacific have been compiled for 187 sites, 105 of which contain chert. The spatial pattern of siliceous deposits in the Pacific generally follows the pattern of biologic productivity. There is some evidence that enhanced vertical diffusivity in the ocean during the Eocene warm climate gave rise to siliceous deposits on and near bathymetric highs and basin margins. The most common occurrence of chert is in Eocene and older sections; however, cherts do occur in sections as young as 7 Ma in the sites investigated. Over half of the youngest chert occurrences in sedimentary sections are within 150 m of basement. Nearly all the chert occurrences on crust younger than 60 Ma are within 150 m of basement. The deficit in heat flow over ocean crust younger than 60 Ma is explained as the result of heat advection by hydrothermal waters circulating in the upper part of the ocean crust. These waters appear to dissolve biogenic silica and deposit it as chert in the lower parts of sedimentary sections. Diffusion of these waters into the lower sediment section is enhanced by small-scale faulting. This faulting may be associated with intra-plate stresses that develop during ridge jumps and reorientations of plate motion. The relatively warm bottom waters of the early Cenozoic may have also enhanced the dissolution of biogenic silica during hydrothermal circulation in the upper oceanic crust and basal sediment section.
The antigenic structure of the acetylcholine receptor from torpedo californica

The immunological structure of the acetylcholine receptor (AChR) from the electric organ of Torpedo californica was studied using a large number of monoclonal antibodies which were initially selected for their abilities to bind to intact AChRs. The monoclonal antibodies were tested for their ability to bind to denatured AChR subunits labeled with 125I. Antibodies derived from rats immunized with individual denatured subunits or a mixture of subunits of Torpedo AChR reacted well in the assay. A much smaller proportion of antibodies derived from rats immunized with native Torpedo AChR or native AChR from Electrophorus electricus electric organ, bovine muscle, or human muscle reacted with denatured subunits of Torpedo AChR. Many monoclonal antibodies reacted with more than one subunit, but they always reacted best with the subunit used for immunization. Those monoclonal antibodies that bound to intact subunits were mapped more precisely by their ability to bind characteristic fragments of each subunit generated by proteolysis with Staphylococcal V8 protease. These fragments were analyzed by SDS polyacrylamide gel electrophoresis, and monoclonal antibodies that precipitated the same fragment pattern were placed in groups. By this method, we define a minimum of 28 determinants on Torpedo AChR.
Total Synthesis of (+)-Azaspiracid-1. An Exhibition of the Intricacies of Complex Molecule Synthesis

The synthesis of the marine neurotoxin azaspiracid-1 has been accomplished. The individual fragments were synthesized by catalytic enantioselective processes: A hetero-Diels−Alder reaction to afford the E- and HI-ring fragments, a carbonyl-ene reaction to furnish the CD-ring fragment, and a Mukaiyama aldol reaction to deliver the FG-ring fragment. The subsequent fragment couplings were accomplished by aldol and sulfone anion methodologies. All ketalization events to form the nonacyclic target were accomplished under equilibrating conditions utilizing the imbedded configurations of the molecule to adopt one favored conformation. A final fragment coupling of the anomeric EFGHI-sulfone anion to the ABCD-aldehyde completed the convergent synthesis of (+)-azaspiracid-1.
Bcl-2 Suppresses Oxidative Phosphorylation Defects Caused by Mitochondrial DNA Mutations.

INTRODUCTION. The protooncogene Bcl-2 prevents apoptosis by still unknown mechanisms. Bcl-2 has been shown to localize to multiple cell compartments, but mainly to the mitochondria. Bcl-2 has been shown to prevent loss of mitochondrial membrane potential and activation of the mitochondrial permeability transition pore (1), which might be responsible for the activation of some apoptotic pathways. Mutations in the mitochondrial DNA (mtDNA) are associated with a heterogeneous group of sporadic or maternally inherited metabolic disorders. We have analyzed the effects of Bcl-2 overexpression in transmitochondrial cell lines (cybrids) harboring pathogenic mtDNA mutations, to investigate if the Bcl-2 protective effect on mitochondrial function could be extended to primary defects of the mitochondrial respiratory chain.
Ligand-Binding Mass Spectrometry to Study Biotransformation of Fusion Protein Drugs and Guide Immunoassay Development: Strategic Approach and Application to Peptibodies Targeting the Thrombopoietin Receptor

The knowledge of in vivo biotransformation (e.g., proteolysis) of protein therapeutic candidates reveals structural liabilities that impact stability. This information aids the development and confirmation of ligand-binding assays with the required specificity for bioactive moieties (including intact molecule and metabolites) for appropriate PK profiling. Furthermore, the information can be used for re-engineering of constructs to remove in vivo liabilities in order to design the most stable candidates. We have developed a strategic approach of ligand-binding mass spectrometry (LBMS) to study biotransformation of fusion proteins of peptides fused to human Fc (“peptibodies”) using anti-human Fc immunoaffinity capture followed by tiered mass spectrometric interrogation. LBMS offers the combined power of selectivity of ligand capture with the specificity and detailed molecular-level information of mass spectrometry. In this paper, we demonstrate the preclinical application of LBMS to three peptibodies, AMG531 (romiplostim), AMG195(linear), and AMG195(loop), that target the thrombopoietin receptor. The data show that ligand capture offers excellent sample cleanup and concentration of intact peptibodies and metabolites for subsequent query by matrix-assisted laser desorption ionization time-of-flight mass spectrometry for identification of in vivo proteolytic points. Additional higher-resolution analysis by nanoscale liquid chromatography interfaced with electrospray ionization mass spectrometry is required for identification of heterogeneous metabolites. Five proteolytic points are accurately identified for AMG531 and two for AMG195(linear), while AMG195(loop) is the most stable construct in rats. We recommend the use of LBMS to assess biotransformation and in vivo stability during early preclinical phase development for all novel fusion proteins.
The effect of thyroxine on transparency and PAPS synthesis in the avian cornea

Abstract The normal onset of developing corneal transparency, which begins on Day 14 of chick embryogenesis, can be accelerated by the in vivo application of exogenous thyroxine, as originally demonstrated by Coulombre and Coulombre (1964, Exp. Eye Res. 3, 105–114). When thyroxine (5 μg) is injected at Day 6, measurements of 35 SO 2− 4 incorporation by corneal homogenates indicate that synthesis of 3′-adenosine phosphosulfate (APS) in the cornea is increased at Day 8, but not that of 3′-phosphoadenosine-5′-phosphosulfate (PAPS). Injection of hormone at Day 9 results in a precocious increase in corneal transparency at Day 12 and a corresponding increase in the synthesis of APS and PAPS.
Black suicide attempters in 1980: A preventive focus

A retrospective chart review of black suicide attempters was completed to describe the sample in comparison to prior studies and to develop preventive strategies. This sample of 56 black suicide attempters was composed of 17 males and 39 females, a ratio of 1:2.3. Female attempters were younger, 54% had made a prior attempt and had a diagnosis of either affective illness (33%) or an adjustment reaction with depressive features (31%). Male attempters were older, 76% had a prior psychiatric history, and 59% had a psychotic diagnosis. The potential for life-threatening behavior in psychotic black male patients was noted. The necessity of monitoring the access to medication by stressed impulsive youth was emphasized. As significant others involved in the stressers that precipitated the attempt accompanied the patient to the emergency room (ER), crisis intervention in the ER with the significant other and/or family members was identified as an important strategy.
Volatile element influx on Venus from cometary impacts

Abstract Several different reasonably concordant methods of estimating the flux of carbonaceous chondrite and cometary material (both meteoric dust and comet nuclei) through the inner solar system are shown to imply that such sources may have a dominant effect on the present abundances of several important constituents of the atmosphere of Venus. In particular, the entire supply of hydrogen compounds on Venus may owe its origin to infall of such material. The escape rate of atomic hydrogen may be in approximate balance with the influx rate of hydrogen in the forms of bound meteoritic water and cometary ices. I suggest that the atmospheric inventories of H, S, Cl, F and possibly N on Venus are provided by infall, and need not be endogenous to Venus.
Long voltammetric microelectrode for in vivo monitoring of acetaminophen in primate species

Abstract A long (45 cm) voltammetric microelectrode for in vivo monitoring of acetaminophen in primate species is described. Due to its length, intravascular insertion is feasible into regions of effective blood circulation. The working electrode is made of carbon paste, placed at the end of a Teflon tubing. Acetaminophen is detected in vivo , in rhesus monkey blood stream, following its intravenous (i.v.) administration. Differential pulse voltammetry with a relatively fast scan rate (2 V/min) is employed to allow rapid assessment of blood concentration of a drug (up to 90 measurements per hour). Well defined peak voltammograms are obtained. In the anodic potential range of whole blood voltammograms, no differential pulse peaks are observed. Despite the obvious problems associated with voltammetric measurements in a complex environment such as whole blood, the method appears to be suited for in vivo monitoring of oxidizable drugs.
Toxicity and cost-effectiveness analysis of intensity modulated radiation therapy versus 3-dimensional conformal radiation therapy for postoperative treatment of gynecologic cancers

Abstract Objective To evaluate toxicity and cost-effectiveness of intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3DCRT) in the postoperative treatment of uterine and cervical cancer. Methods Between 2000 and 2012, eighty patients at our institution received post-hysterectomy 3DCRT (46) or IMRT (34) for uterine or cervical cancer. Baseline characteristics, outcome, and ≥CTCAE grade 2 toxicities were compared between the two groups. Predictors of toxicity-free survival were identified. A decision analysis model was designed to capture individual health states at 1, 2, and 3years after treatment. Micro-costing technique and estimated quality-adjusted life years (QALYs) were used to calculate incremental cost-effectiveness ratio (ICER). Results Utilization of IMRT increased from 25% (2005–2007) to 75% (2008–2012). Recurrence-free and overall survival rates were not different between the two groups. Toxicity rates were reduced with IMRT versus 3DCRT (HR 0.42, p=0.04). Women who received IMRT had numerically lower rates of late gastrointestinal and genitourinary toxicity and significantly lower rates of late overall toxicity at 3years (16% vs. 45%, p=0.04). On univariate analysis, IMRT was associated with decreased late toxicity (HR 0.43, p=0.04). Treatment costs were higher and toxicity costs were lower with IMRT. IMRT had an ICER of $235,233 (year 1), $114,270 (year 2), and $75,555 (year 3) per QALY gained. Conclusion IMRT is associated with reduced late overall toxicity compared to 3DCRT without compromising clinical outcome. IMRT is not cost-effective during the early chronic toxicity phase, but it becomes more cost-effective over time.
On the implications of surface reciprocal relations for thermophoresis and photophoresis

Abstract The steady state thermophoretic, photophoretic, and drag forces on a sphere are obtained in the case of hydrodynamics using boundary conditions consistent with the surface reciprocal relation discussed in the preceding paper (I). These boundary conditions yield expressions for the forces which are in qualitative disagreement with experiment. New boundary conditions consistent with the reciprocal relation given in I are proposed which allow for singular energy transport at the particle surface. These boundary conditions give qualitatively correct behavior for dense fluids, but still fail for rarified gases. This failure confirms the fact that the hydrodynamic approach to thermophoresis and photophoresis is inapplicable when the kinetic boundary layer (i.e. the Knudsen layer) is larger than the characteristic dimension of the problem, here the particle size. Comparison is made with the theory of Waldmann et al. (Nuovo Cimento 25B (1975) 407) and in particular we show that the reversible part of the singular energy transport must also be included in the reciprocal relation.
Estimation of rest-activity patterns using motion sensors

Disrupted sleep patterns are a significant problem in the elderly, leading to increased cognitive dysfunction and risk of nursing home placement. A cost-effective and unobtrusive way to remotely monitor changing sleep patterns over time would enable improved management of this important health problem. We have developed an algorithm to derive sleep parameters such as bed time, rise time, sleep latency, and nap time from passive infrared sensors distributed around the home. We evaluated this algorithm using 404 days of data collected in the homes of 8 elderly community-dwelling elders. Data from this algorithm were highly correlated to ground truth measures (bed mats) and were surprisingly robust to variability in sensor layout and sleep habits.
Food in Colonial and Federal America – By Sandra L. Oliver

This book is second in a series dealing with “Food in American History” by Greenwood Press. The “Series Forward” promises that all its volumes will conform to a format that begins with a “Chronolog...
A scanning electron microscopic and flame spectrometry study on the role of Ca2+ in amphibian neurulation using papaverine inhibition and ionophore induction of morphogenetic movement

SEM observations reveal that papaverine, which interferes with Ca2+ flux, inhibits neural fold formation causing a flattening of the cellular surface and a broadening of cellular junctions. Ionophore A23187 and EGTA both counter this effect promoting a rapid cellular constriction which results in the formation of neural ridges and folds as individual cells become uplifted and ruffled. Flame spectrometry data indicate that as Ambystoma maculatum or mexicanum embryos neurulate Ca2+ is released to the medium, a condition which is impeded by papaverine. Ionophore A23187 induces Ca2+ influx whereas EGTA induces an efflux. Since both agents affect similar morphological changes it is suggested that the availability of free Ca2+ is crucial in controlling the morphogenetic movements of neurulation. It is now apparent that neuro-axial development in the urodele is accompanied by a Ca+2 efflux, but the mechanism(s) responsible for the ion's release is unknown.
Mabel Agnes Elliott, We Hardly Knew You

Sociologist Mabel Agnes Elliott was elected the fourth president of the Society for the Study of Social Problems in 1956–1957 and was the first woman to hold this position. She was an anti-war activist, a feminist and a creative and diligent writer. Yet she experienced many challenges. The Federal Bureau of Investigation kept an active file on Elliott for approximately 30 years, she was the victim of discrimination by her male colleagues at the University of Kansas where she spent much of her career and Professor Robert E. L. Faris used many of the ideas from her Social Disorganization textbook without attribution. In spite of her research productivity her salary was frozen for 18 years. Once she began teaching women at Chatham College she found an institution that appreciated her many talents and rewarded her appropriately. Even so, in a male-dominated discipline, her contributions to criminology and social disorganization have been nearly forgotten.
The GRAD Gamma Ray Spectrometer

A gamma-ray spectrometer for an upcoming space shuttle mission is described. Consisting of a 150 cm3 n-type germanium detector set inside active shielding of bismuth germanate and plastic scintillator, the instrument will be used in studies of the Orbiter background and the galactic center.