cssi/SciSciGPT-SciSciNet huggingface dataset:
Dimer formation in immunoglobulin preparations and speculations on the mechanism of action of intravenous immune globulin in autoimmune diseases

IgG dimers occurring in therapeutic Ig preparations have been characterized as Id-anti-Id, in that the sites of interaction are localized to the distal tips of the Fab arms. The observation that such dimers are prevalent in Ig or Igi.v. prepared from large plasma pools, but absent in preparations from a single individual, supports the notion that the individual immune repertoire is small with respect to the species repertoire. A crude mathematical model that attempts to relate Id-dimer content to the number of donors is presented. This model suggests that Id-pairs may be much more prevalent in Ig than is reflected by the Id-dimer content, inasmuch as the concentrations of the individual Ids and anti-Ids may limit the equilibrium level of dimer. The model further suggests that the antibody diversity in Ig derived from thousands of donors may be representative of the species repertoire; hence, virtually all specificities, including anti-Id specificities, will be included. Because Ig is derived from normal healthy donors, it should be relatively free of pathogenic autoantibodies. However, there is no reason to suspect that anti-Ids to such autoantibodies would not occur, and indeed the presence of such anti-Ids has been demonstrated. Several mechanisms have been proposed by which such anti-Ids might ameliorate autoimmune disease. They may directly inhibit the binding of autoantibody to its target antigen, or they may target for destruction those cells expressing or secreting autoantibody. It may well be that anti-Ids play no role in the mechanism of action of Igi.v. in autoimmune disease. Such appears to have been demonstrated, for example, in the treatment of ITP. There is an obvious need for additional studies in order to elucidate the mechanism of action of Igi.v. in various autoimmune diseases. Experimental animal models of autoimmune disease, such as the mouse model for systemic lupus erythematosus (Mozes et al. 1993), might be very useful in this regard. Finally, it needs to be emphasized that the usefulness of high doses of Igi.v. in many autoimmune diseases remains to be established by controlled clinical trials. Because Igi.v. is a limited resource, and one which cannot be produced through biotechnological advances (at least in the foreseeable future), its widespread use should be restricted to the treatment of diseases for which efficacy has been demonstrated. To do otherwise might deprive appropriate patients of a valuable therapy.
Natural products which interact with tubulin in the vinca domain: Maytansine, rhizoxin, phomopsin a, dolastatins 10 and 15 and halichondrin B

This paper summarizes published data on the interactions of tubulin with antimitotic compounds that inhibit the binding of vinca alkaloids to the protein. These are all relatively complex natural products isolated from higher plants, fungi and marine invertebrate animals. These agents are maytansine, rhizoxin, phomopsin A, dolastatins 10 and 15 and halichondrin B and their congeners. Effects on tubulin polymerization, ligand binding interactions and structure-activity relationships are emphasized.
THE SITE OF ACTION OF THE STAPHYLOCOCCUS ALPHA TOXIN

The present study concerns the site of action of the staphylococcus alpha toxin. This powerful necrotizing agent produced by pathogenic strains of staphylococcus is very probably important in the pathogenesis of localized staphylococcus disease and in the shock-like picture sometimes associated with staphylococcus septicemia. Our previous studies had suggested that the toxin has a selective effect on vascular smooth muscle. In investigating this problem further, the following observations were made. 1. The toxin produces an immediate hyperperistalsis and sustained increase in intraluminal tension progressing ultimately to atony and flaccid paralysis in the isolated smooth muscle preparation. 2. The addition of specific antitoxin prior to exposure to toxin prevents this reaction. However, when antitoxin is added after the toxin, no ameliorating effect is seen. 3. The toxin is rapidly and irreversibly bound to its substrate since washing the bowel segment 30 seconds after exposure to toxin fails to change the course of the reaction. 4. Vena caval segments exposed to toxin exhibit a similar initial rise in intraluminal tension followed by flaccid paralysis at which point they no longer respond to epinephrine stimulation. 5. When the toxin is infiltrated in the neighborhood of muscular blood vessels in the living rabbit selective necrosis of smooth muscle cells of the vessel walls is seen. 6. The selective effect on smooth muscle is emphasized by the failure of the toxin to affect the contractility of skeletal and cardiac muscle. 7. Perfusion of the isolated kidney and heart produces an increased resistance to flow after toxin is added to the perfusate. 8. Epithelial cells and fibroblasts in tissue culture exposed to high concentration of toxin for 2 hours are unaffected in their ability to recover and metabolise. This is in marked contrast to the effect on the smooth muscle preparation. The probability that the toxic effect on smooth muscle cells explains some of the local and systemic effects of staphylococcus infection is discussed.
Influence of coefficient of friction on fretting fatigue crack nucleation prediction

The role of coefficient of friction (COF) on fretting fatigue damage prediction is studied using an elastic/plastic finite element analysis (FEA) of an experimental fretting fatigue test. At a scale on the order of tens of microns, the COF has a large impact on fretting fatigue damage prediction. By using a higher COF than that determined from conventional gross sliding tests, along with critical plane multiaxial fatigue damage models, the life and experimentally observed damage at this scale appear to be better predicted. Potential origins of this higher effective COF are discussed.
Reflection and absorption of Alfvénic power in the low-altitude magnetosphere

[1] Results from a numerical study of the nonlinear interaction between large-amplitude Alfven waves and the low-altitude auroral magnetosphere and ionosphere are presented. In the model the Alfven wave encounters collisionless resistive dissipation when and where the effective parallel drift of electrons carrying the wave field-aligned current density exceeds a critical threshold corresponding to onset of current-driven microinstability. The resulting parallel electric field and parallel potential drop introduce frequency, amplitude, and perpendicular length-scale dependence in the absorption of Alfven wave power. Analysis of the power flow shows that (1) most of the power generated by a constant-current source in the magnetosphere and carried by relatively small-amplitude, high-frequency, and short transverse wavelength Alfven waves is reflected at low altitudes by the wave-induced collisionless resistive layer (RL); (2) Alfven wave power is absorbed primarily in the RL except when stimulated by a constant-voltage generator, wherein ionospheric Joule heating dominates the absorption at large transverse length scales; (3) the absorption is high (≈0.8) at length scales of 10–20 km (ionospheric projection) for constant voltage source conditions; and (4) the relation between the wave-induced parallel potential drop and wave field-aligned current is linear with proportionality constant of order 109 Ω-m2 over much of the range of interest. Correspondence between predicted properties and satellite observations is demonstrated.
A simple economic model of endangered species preservation in the United States

Abstract Concern for the acceleration in threats to species diversity in the United States led to the passage of the Endangered Species Act of 1973. In this paper, this legislation is examined in an economic context. A simple model is developed where management and constraints on economic activity are substitutes in the production of species stocks. Whether economic growth constraints (the primary policy tool of the 1973 Act) are justified for preservation purposes depends on technical substitution possibilities, relative cost ratios, and the existence of budget constraints for species management. Since the same combination of these factors will not occur for all species, it is argued that more flexibility in endangered species policy may preserve the same levels of species stocks at lower costs to society.
The electrophoretic separation of isoaccepting transfer ribonucleic acids.

Abstract Isoaccepting tRNA's as their mixed trialkylammonium salts have been separated electrophoretically on a normally hydrophobic support membrane. In studies on baker's yeast tRNA, the two known major Met-tRNA's have been well separated from one another and from what may be a minor Met-tRNA. An electrophoretic study of two major Met-tRNA species after their separation by reversed-phase partition chromatography indicates that the less lipophilic of the two species has the higher electrophoretic mobility. One major and four minor radioactive loci have been found on the electrophorograms of baker's yeast tRNA which had been charged with [ 14 C]phenylalanine. The nature of the Phe-tRNA's which occupy the minor loci remains to be determined. It is suggested that they may include undermethylated precursor forms of the main Phe-tRNA species of baker's yeast.
Conformations of septanosides. The crystal and molecular structure of 5-O-(chloroacetyl)-1,2:3,4-di-O-isopropylidene-α-D-glucoseptanose

Abstract The crystal structure of 5-O-(chloroacetyl)-1,2:3,4-di-O-isopropylidene-α- D -glucoseptanose, a seven-membered ring sugar, has been determined by using 1234 reflections measured on a diffractometer. The crystals belong to the orthorhombic space group P212121, having cell dimensions a  27.750, b  10.714, and c  5.702 A. The measured and calculated densities are 1.25 g.cm−3 and 1.32 g.cm−3, respectively; the latter value assumed four molecules in the unit cell. The structure was determined by a combination of the heavy-atom technique and the tangent method. Full-matrix least-squares refinement with anisotropic temperature factors for the nonhydrogen atoms and isotropic temperature factors for the hydrogen atoms lowered the conventional R value to 0.066. The seven-membered ring adopts a 5.6C2( D ) twist-chair conformation. Both of the dioxolane rings have the envelope shape, the puckered atoms being C-2 and C-4 of the seven-membered ring. The molecular packing is dominated by Van der Waals forces. The conformations of three known 7-membered ring sugars are compared. It is found that the pseudorotation of the septanose ring and the dioxolane rings are correlated to the position of attachment of the latter rings to the central septanose ring.
Shape-from-shading is independent of visual attention and may be a 'texton'

—Shading was used to generate the appearance of an obliquely illuminated surface with spherical indentations and protrusions. The "pop-out" of an apparent indentation among numerous apparent protrusions served as a psychophysical assay for shape-from-shading. Detectability of the pop-out varied with the direction of apparent illumination, a finding which is characteristic for shape-from-shading and which demonstrated the appropriateness of this assay. Observers were able to concurrently detect two shape-from-shading pop-outs in different parts of the display, demonstrating that shape-from-shading is a parallel process. In another experiment, visual attention was engaged by a letter discrimination task. Nevertheless, observers were able to detect a shape-from-shading pop-out concurrently in the unattended part of the display, suggesting that shape-from-shading is independent of visual attention. Thus, shape-from-shading shares some of the characteristics of Julesz' textural stimulus dimensions ('textons').
The Rape of Boys and the Impact of Sexually Predatory Environments: Review and Case Reports

This paper describes the effect of rape and the impact of sexually predatory environments on young boys and the resulting sequelae in adulthood. It presents the literature and the case histories of Jeff and Todd to illustrate the psychic devastation that occurs, and the ensuing attempts at reestablishing boundaries and regaining a sense of autonomy and male identity. Issues including facing powerlessness, betrayal by trusted adults, and the effect of emasculation on developing sexual identity are explored. A study of almost 4,000 siblings by Nelson et al. (2002) showed that a twin who was not sexually abused himself but who grew up in the same milieu as his sexually abused twin, suffered similar psychopathologic symptoms, such as suicide attempts, alcohol dependence, and social anxiety. Todd spent his formative years in a Catholic boarding school where boys were physically and sexually abused by priests. His history illustrates the severe psychological damage this causes and is consistent with the findings of Nelson's study.
Comparison of litter dynamics in native and exotic riparian vegetation along the Middle Rio Grande of central New Mexico, U.S.A.

Abstract Exotic plants and river regulation have changed riparian ecosystems throughout the south-western U.S. We compared litter dynamics at sites dominated by native cottonwoods or exotic saltcedar in the Middle Rio Grande Valley of central New Mexico. Litter production was greater at cottonwood sites and may have increased after experimental flooding in cottonwood but not in saltcedar. Decomposition was similar for both types of leaves and increased with experimental flooding for both. Forest floor litter was greater at cottonwood sites; litter storage decreased after flooding at the saltcedar site but not at the cottonwood site. Flooding may help reduce the impact of fires by increasing decomposition and reducing the standing stock of forest floor organic matter.
Thick boride coatings by chemical vapor deposition

In this paper we describe an experimental study of the chemical vapor deposition (CVD) of TiB2 by the hydrogen reduction of TiCl4 and BCl3 with the purpose of obtaining very thick (more than 100 μm) and uniform coatings. The optimum deposition conditions were as follows: temperature, 900–950 °C; source gas ratios, [Ti]/[B] = 12 and [H]/[Cl] = 61. With these conditions, deposition rates greater than 25 μm h-1 were obtained. The composition was very uniform with an excess of boron over stoichiometry (probably in the form of free boron). A small amount of chlorine remained incorporated in the deposit probably as TiCl2 (0.05 wt.% at 950 °C). The coatings were very hard (about 3700 kgf mm-2) and hardness was uniform through the thickness. With careful control of the deposition parameters, the CVD of uniform coatings with thickness of 1 mm or more appears feasible.
Packed capillary column solvating gas chromatography of aldehydes

The rapid separation of aldehydes of environmental interest was investigated using packed capillary column solvating gas chromatography (SGC). Fused-silica capillary columns (250 μm I.D.) were packed with poly(dicyanoallylsiloxane)-encapsulated 10 μm spherical porous (80 A) silica particles. Excellent resolution and good peak shapes were achieved for underivatized aldehydes using carbon dioxide as mobile phase. The effects of temperature and pressure on column efficiency and selectivity were studied. Packed capillary SGC gave better resolution of ten standard aldehydes than open tubular gas chromatography using poly(biscyanopropylsiloxane) as stationary phase, and near-baseline resolution of these aldehydes was obtained in approximately 60 s.
The rule breaking Cr2(CO)10. A 17 electron Cr system or a Cr?Cr double bond?

Density functional theory (DFT) has been used to investigate the conformations and thermochemistry on the singlet and triplet potential energy surfaces (PES) of Cr2(CO)10. The global minimum energy structure for the lowest singlet state of C2h symmetry is consistent with a model of two interacting Cr(CO)5 fragments in which one carbonyl in each fragment acts as an asymmetric four-electron donor bridging carbonyl, with chromium-chromium distances of 2.93 A (B3LYP) or 2.83 A (BP86). Avoiding a Cr⋯Cr bond by incorporating four-electron donor CO groups in this way allows each chromium atom in singlet Cr2(CO)10 to attain the favored 18-electron configuration by using, in a simple picture of the bonding, only the six octahedral sp3d2 hybrids. The dissociation energy to two Cr(CO)5 fragments or to Cr(CO)6 + Cr(CO)4 fragments is predicted to be 10 kcal mol−1. The lowest triplet state of Cr2(CO)10 is predicted to lie ∼10 kcal mol−1 above the singlet global minimum. In the case of triplet Cr2(CO)10 the lowest energy minima were found to be of C2 and C2h symmetry, with similar energies. The chromium-chromium distances in triplet Cr2(CO)10 were found to be shorter than those in the corresponding singlet structures, namely 2.81 (B3LYP) or 2.68 A (BP86) suggesting a σ + 2(1/2) π CrCr double bond similar to the OO bond in O2 or the FeFe bond in the experimentally observed triplet state (Me5C5)2Fe2(μ-CO)3.
In Vivo Evaluation of Brown-Midrib Corn Silage by Sheep and Lactating Dairy Cows

Abstract Brown-midrib (bm 3 ) corn silage was compared with normal genetic corn silage after ensiling. Analytical contents for dry matter, crude protein, nitrogen-free extract, ether extract, crude fiber, acid detergent fiber, and ash were similar, but acid detergent fiber and lignin was reduced in brown-midrib silage. Wethers fed brown-midrib silage consumed 1.36kg dry matter per day compared to 1.15 when fed normal control silage. Apparent digestibility of dry matter (70.9 versus 64.3%) and acid detergent fiber (61.8 versus 46.8%) were greater for wethers fed brown-midrib silage. Apparent nitrogen digestibility was not different (59.7 versus 60.6%);however, nitrogen absorbed was greater when wethers were fed brown-midrib silage (15.0 versus 13.4g/day). In a single reversal lactation trial, 20 cows consumed more silage dry matter when offered brown-midrib silage ad libitum than when control silage was fed (8.7 versus 8.1 kg/day), but total dry matter intake was not different (17.6 versus 17.1 kg/day). Milk production (actual or 4% fat-corrected) was not different. Body weight change (kg/day) was .19 during feeding of brown-midrib and .11 during feeding of normal silage. Even though brown-midrib silage was more palatable and digestible in sheep, there was no difference in milk production when it was fed to cows averaging 109 days postpartum in a switch-over trial of 100 days.
Behavioral defenses of crepidula fornicata against attack by urosalpinx cinerea

Two behavioral defenses of the slipper shell Crepidula fornicata (L.) against attack by the oyster drill Urosalpinx cinerea (Say) are described: (1) Jabbing: when an oyster drill approaches, the slipper shell lifts the edge of its shell, extends the head and, with the radula, pricks or rasps the foot of the predator, which instantly retracts into its shell; sometimes, after repeated approaches, the oyster drill moves away. (2) Pivoting: when an oyster drill mounts C. fornicata, the latter slowly and repeatedly rotates its shell in a horizontal plane at a constant rate and through a constant arc. If this action brings the predator's shell to bear against an obstacle, motion ceases and C. fornicata maintains the pressure until the oyster drill is dislodged. These aggressive tactics are adaptive defensive measures for a nearly sessile prey otherwise highly vulnerable to oysterdrill attack.
Miliary tuberculosis and the postpartum state

In 1985, a resurgence of tuberculosis began in the United States. In conjunction with this resurgence, there has been an increase in the number of atypical presentations of the disease. We recently treated a patient who had disseminated tuberculosis that became manifest in the postpartum state. Whereas postpartum progression of tuberculosis was a well-recognized clinical entity in the preantibiotic era, few reports have dealt with the issue recently. We present this case as a timely reminder of the many faces of tuberculosis.
MP26, a protein of intercellular junctions in the bovine lens: electrophoretic and chromatographic characterization.

Abstract We have characterized the membrane protein of apparent molecular weight 26 kD from bovine lenses (MP26 or MIP) with respect to six different electrophoretic and chromatographic procedures. These include one- and two-dimensional gel electrophoretic procedures, as well as SDS-hydroxylapatite chromatography. The two-dimensional gels include isoelectric focusing with both conventional ampholytes and buffer focusing methods. With buffer focusing, the membranes are solubilized without the use of SDS and the isoelectric focusing is performed in the absence of SDS. As specific probes for MP26, a monoclonal antibody and an anti-MP26 rabbit serum were used, the latter prepared against electrophoretically purified MP26. These separation techniques were adapted to MP26 in order to permit a more detailed characterization of this protein and to search for any heterogeneity in this size range, specifically other junctional proteins or protein fragments. We have found evidence for charge heterogeneity in MP26, but no evidence for multiple membrane proteins of M r 26 000 in urea-treated membranes. The charge heterogeneity appears to be related to a phosphorylation of MP26. The results reported here aid the interpretation of a variety of data, especially findings on the reconstitution of MP26 in artificial membranes and results from work with polyclonal MP26 antibodies. These investigations are all designed to evaluate the proposed role of MP26 as a protein of cell-to-cell channels in the lens fiber cell.
Abstract PR5: Treatment of ovarian cancer with targeted tumor-penetrating siRNA nanocomplexes

Abstract Whole-genome analysis of cancer samples is identifying many potential therapeutic targets, by virtue of their being frequently mutated or functionally essential in specific types of cancer. However, we lack efficient ways to test the therapeutic benefit of modulating targets in vivo. RNAi offers one potential solution; however, approaches to deliver siRNA in vivo have been challenging due to their susceptibility to serum nucleases, endosomal entrapment, and stimulation of innate immunity. Furthermore, nanoparticle- and antibody-based siRNA delivery approaches have historically suffered from limited tumor penetration and low transvascular transit, thereby limiting the applicability of parenchymal siRNA targets. Here we describe a tumor penetrating nanocomplex (TPN) comprised of siRNA complexed to a tandem tumor-penetrating and membrane-translocating peptide, which enables the homing of siRNA deep into tumor parenchyma. Upon complexation with siRNA, the resulting nanocomplex is stable, non-immunostimulatory, displays homing peptides in a multivalent fashion that increases their binding avidity and delivers siRNA to the cytosol of tumor cells through receptor-specific interactions and membrane translocation. Upon systemic administration into mice, this nanocomplex penetrates into the parenchyma of metastatic peritoneal tumors and silences target genes in cells of interest in a receptor-specific manner. We employed TPNs in vivo to evaluate ID4, a novel candidate oncogene in ovarian cancer, which we identified by combining genome-scale RNAi screening of cancer cell lines with genome-scale sequence analysis of patient tumors. We show that treatment of tumor-bearing mice with ID4-specific TPNs suppresses tumor growth and significantly improved survival. These findings provide a framework for the identification, credentialing, and understanding of novel cancer targets as well as validating a specific therapeutic target in ovarian cancer. This abstract is also presented as Poster B2. Citation Format: Yin Ren, Hiu Wing Cheung, Ronny Drapkin, David Root, Justin Lo, Valentina Fogal, Erkki Ruoslahti, William Hahn, Sangeeta Bhatia, Geoffrey von Maltzahn, Amit Agrawal, Glenn Cowley, Barbara Weir, Jesse Boehm, Pablo Tamayo, Jill Mesirov, Alison Karst. Treatment of ovarian cancer with targeted tumor-penetrating siRNA nanocomplexes [abstract]. In: Proceedings of the AACR Special Conference on Noncoding RNAs and Cancer; 2012 Jan 8-11; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(2 Suppl):Abstract nr PR5.
Recovery-Based Error Estimator for the Discontinuous Galerkin Method for Nonlinear Scalar Conservation Laws in One Space Dimension

In this paper, we propose and analyze a robust recovery-based error estimator for the original discontinuous Galerkin method for nonlinear scalar conservation laws in one space dimension. The proposed a posteriori error estimator of the recovery-type is easy to implement, computationally simple, asymptotically exact, and is useful in adaptive computations. We use recent results (Meng et al. in SIAM J Numer Anal 50:2336---2356, 2012) to prove that, for smooth solutions, our a posteriori error estimates at a fixed time converge to the true spatial errors in the $$L^2$$L2-norm under mesh refinement. The order of convergence is proved to be $$p + 1$$p+1, when $$p$$p-degree piecewise polynomials with $$p\ge 1$$p?1 are used. We further prove that the global effectivity index converges to unity at $$\mathcal {O}(h)$$O(h) rate. Our proofs are valid for arbitrary regular meshes using $$P^p$$Pp polynomials with $$p\ge 1$$p?1, under the condition that $$|f'(u)|$$|f?(u)| possesses a uniform positive lower bound, where $$f(u)$$f(u) is the nonlinear flux function. We provide several numerical examples to support our theoretical results, to show the effectiveness of our recovery-based a posteriori error estimates, and to demonstrate that our results hold true for nonlinear conservation laws with general flux functions. These experiments indicate that the restriction on $$f(u)$$f(u) is artificial.
A prospective study of bone lead concentration and death from all causes, cardiovascular diseases, and cancer in the Department of Veterans Affairs Normative Aging Study.

Background— Blood lead concentration has been associated with mortality from different causes in several studies. Many effects of lead exposure that might increase risk of death are likely to result from cumulative exposure, for which bone lead is a better biomarker than blood lead. The association between bone lead levels and mortality has not been explored. Methods and Results— We prospectively assessed the association between both blood lead and bone lead, analyzed with the use of K-shell x-ray fluorescence, and mortality among 868 men in the Normative Aging Study. We identified 241 deaths over an average of 8.9 (SD=3.9) years of follow-up. We calculated adjusted hazard ratios and 95% confidence intervals using Cox proportional hazards. Compared with the lowest tertile of patella bone lead, the fully adjusted hazard ratios in the highest tertile for all-cause, cardiovascular (n=137 deaths), and ischemic heart disease (n=62 deaths) mortality were 1.25 (95% confidence interval, 0.82 to 1.92), 1.42 (95% c...
Silicon Solid/State Linear Arrays For Multisfectral High Resolution Imaging Systems

Solid-state, electronically scanned, linear detector arrays are now available which can be used in a pushbroom scan mode imaging system for high-resolution multispectral earth resource survey applications. These arrays provide high performance in the visible to near-IR region. Two performance criteria must be assessed in the choice of a detector array: signal-to-noise ratio and spectral response. Consideration of diffraction limitations shows that optics size cannot be significantly reduced by using very low-noise detectors. The required spectral response for a viable detector array should not have spectral ripples that cause a low-level, but significant, error in the detected effective reflectance of the target.
Acetylcholinesterase and ATPases in motor neuron degenerative diseases

Acetylcholinesterase (AChE) activity was measured in the presence of the specific inhibitor of pseudocholinesterase, iso-OMPA, in plasma from patients with amyotrophic lateral sclerosis (ALS), progressive muscular atrophy (PMA), neuromuscular disease controls, and normal controls. Both AChE and Na-K ATPase activities were measured in erythrocyte ghost membranes from ALS and normal controls. Activities of erythrocyte ghost AChE and Na-K ATPase did not differ between ALS and control patients, suggesting that erythrocyte membranes were normal in ALS. However, the activity of plasma AChE in patients with ALS and PMA was increased significantly over plasma activity in disease controls and normal controls. In addition, in an animal model of human PMA, the Wobbler mouse, plasma AChE activity was increased significantly over littermate controls. The explanation for the increase in plasma acetylcholinesterase was not clear; however, a number of potentially useful clinical points followed from this study. First, there was no relationship between a specific subtype of motor neuron disease and the level of AChE activity. Second, AChE activity appeared to vary directly with the duration of PMA but not with the severity of PMA. This did not correlate with either the duration or severity of ALS. Last, plasma AChE activity was normal in about 30% of patients who had motor neuron disease; therefore, AChE assay had limited use in the diagnosis of ALS or PMA.
The production and secreton of digestive enzymes in the purple seastar Pisaster ochraceus

The purple seastar Pisaster ochraceus contains clearly measurable protease and amylase activity. Centrifuged supernatants of pyloric caeca homogenates undergo a spontaneous threefold increase in protease activity when incubated under toluene for 50 h at 25°C. Amylase activity remains nearly constant over this period. Bovine trypsin at a 1 to 100 ratio (trypsin to supernatant protein) induces a twofold increase in protease activity over that of the control supernatant while having virtually no effect on amylase activity over the control. The data indicate a specific interaction of trypsin with a protease zymogen rather than a conspecific hydrolysis of membrane components or vesicles by trypsin. Two percent Triton X-100 used as a diluent in place of distilled, deionized water causes a sevenfold increase in protease activity and a twofold increase in amylase activity in pyloric caeca supernatants. The use of Triton as a diluent in the preparation of a stomach-tissue supernatant allows quantitative measurement of both protease and amylase activity in that tissue.
Effect of Tube Voltage (100 vs. 120 kVp) on Radiation Dose and Image Quality using Prospective Gating 320 Row Multi-detector Computed Tomography Angiography.

Objectives : The objective of the following study is to evaluate the effect of reducing tube voltage from 120 to 100 kVp using prospective gating 320 row multi-detector computed tomography angiography on image quality and reduction in radiation dose. Materials and Methods : A total of 78 sequential patients were scanned with prospective electrocardiogram gating. A total of 45 patients (Group 1) with mean body mass index (BMI) 29 ± 2 and heart rate (HR) 57 ± 7 beats per minute (BPM) were scanned at 120 kVp. 33 patients (Group 2) with mean BMI 23 ± 3 and HR 58 ± 6 bpm were scanned at 100 kVp. Effective dose was calculated using dose length product and factor (k = 0.014). Quantitative assessment of image quality was calculated by measuring signal to noise ratio (SNR) and contrast to noise ratio (CNR) in the left ventricle and left main coronary artery. Two experienced cardiac radiologists using a three-point ordinal scale assessed subjectively image quality. Results: In Group 1, the median radiation dose was 5.31 mSv (95% confidence interval [CI]: 4.86-6.09) and for Group 2 (P = 0.009) the mean radiation dose was 3.71 mSv (95% CI: 2.76-4.87), representing 30% decrease in radiation dose. In multivariate analyses, adjusting for age, gender, HR, BMI, tube current and scan length, an absolute median reduction of 2.21 mSv (1.13-3.29 mSv) was noted in patients scanned with 100 kVp (P Conclusion: Our study suggests that radiation dose may be lowered from 120 to 100 kVp with preservation of image quality in patient's whose BMI is ≤27.
Many-body and model-potential calculations of low-energy photoionization parameters for francium

The photoionization cross section $\ensuremath{\sigma},$ spin-polarization parameters P and Q, and the angular-distribution asymmetry parameter $\ensuremath{\beta}$ are calculated for the $7s$ state of francium for photon energies below 10 eV. Two distinct calculations are presented, one based on many-body perturbation theory and another based on the model potential method. Although predictions of the two calculations are similar, the detailed energy dependences of the photoionization parameters from the two calculations differ. From the theoretical p-wave phase shifts, we infer quantum defects for ${p}_{1/2}$ and ${p}_{3/2}$ Rydberg series, permitting us to calculate positions of experimentally unknown p states in francium.
Fourier components of moving gratings

In designing experiments in which the proximal stimulus is a moving grating (including cases in which the distal stimulus is stationary but eye movements play a significant role), one must consider the effects of the motion of the stimulus on its Fourier components in the spatiotemporal frequency domain. Some of these effects are unexpected and counterintuitive. For example, the Fourier components of a moving grating do not include its stationary (or “instantaneous”) spatial frequency. Thus there is no linear filter that can extract a stationary grating from a moving one. Several useful relations are given for analyzing such stimuli.
Using Geospatial Techniques to Analyze Landscape Factors Controlling Ionic Composition of Arctic Lakes, Toolik Lake Region, Alaska

The impacts of climate change on landscapes in arctic Alaska are evident in terms of permafrost melting, frequent thermokarst activity, and the occurrence of more broadleaf vegetation. These changes may alter natural biogeochemical cycles of ions along with major nutrients and affect ionic compositions of lakes, as they are connected with the landscapes. However, the nature of the connectivity between lakes and landscapes in this region is not yet explored. The authors propose that geospatial analysis of landscape properties along with observed lake ion concentrations will enable an understanding of the currently existing landscape controls over ion inputs into the lakes. For the watersheds of 41 lakes in the Arctic Foothills region of Alaska, spatial properties of natural vegetation communities expressed in terms of percentage, shape complexity, and patch density metrics were derived using satellite data. Regression analyses were performed for concentration of ions as well as conductivity in lake water where the spatial metrics along with lake physical properties, lake order, and glacial till age categories were used as predicting variables in the regression. Landscape metrics for major land covers i.e., Percentage of Moist Acidic Tundra (MAT) and Moist Non-acidic Tundra (MNT) were the major predicting variables for concentration of several ions.
Blood formation in the african lungfish, under normal conditions and under conditions of prolonged estivation and recovery†

The blood cells of the African lungfish, Protopterus ethiopicus, are very large and resemble those of urodeles. Leucocytes are especially plentiful and rich in variety, including eosinophils, special eosinophils, [meta-eosinophils] with atypical granules, monocytes, thrombocytes, lymphocytes, and basophils. The chief hemocytopoietic organs are the spleen, intestine, and kidneys. The lungfish spleen, embedded in the wall of the stomach, represents an intermediate phylogenetic stage between the disperse intra-enteral type of the hagfish and the compact extra-enteral type of other vertebrates. Erythrocytes are formed in the spleen pulp, granulocytes in the granulocytopoietic organ of the intestine and in the capsules of kidneys, gonads, and spleen. Thrombocytes and monocytes are differentiated in the spleen and general circulation. Basophils arise in the spleen and intestine. Lymphoid cells of all types arise in the spleen. Evidence is presented bearing upon the hemocytopoietic capacity of the various types. Cells with [Russell bodies] also occur in the spleen. In lungfishes subjected to long periods of dry estivation, erythrocytopoiesis practically ceases. Granulocytes, however, appear to play an important rǒle, possibly in fat metabolism. The large variety of meta-eosinophils, a unique feature of the lungfish, appears to be associated with the habit of estivation. Recovery from estivation may show numerous amitoses of erythrocytes in the general circulation. Other cells which divide in this manner are young thrombocytes, granulocytes, monocytes, and lymphoid hemoblasts.
Antifungal Therapy in Pregnancy and Breastfeeding

Antifungal therapy during pregnancy and lactation is challenging because of a lack of data on efficacy and safety, coupled with reports of teratogenicity. Although the Food and Drug Administration pregnancy category provides guidance regarding a drug’s potential fetal risks, limitations such as lack of a specific toxic dose or predisposing pregnancy trimester thwart its application. Central to the selection of optimal antifungal therapy are exploration of the literature and assessment of patient-specific factors, including awareness of effects on the pharmacokinetics of antifungal agents that result from physiologic changes during pregnancy. Topical azoles are favored for superficial fungal infections during pregnancy and lactation, whereas amphotericin B is preferred for invasive fungal infections. Data regarding the use of antifungal agents by breastfeeding women are lacking. More studies are needed, particularly with newer antifungals, to better guide clinicians in selecting optimal antifungal therapy that will provide benefit to the mother without harm to the fetus.
Archaeological proxies for sediment flux to Holocene littoral cells of southern California

Postglacial environments of coastal regions respond to changes in sea level, tectonics, and climate. Adjustments in sedimentary regimes along the coast also occur during periods of rising sea level, altering littoral habitats. Species diversity and biomass of marine invertebrates depend on the nature of the intertidal zone represented by rocky open coast, sandy beach, or quiet water embayment. Prehistoric human settlement of the southern California coast began in the early Holocene, and the marine invertebrate record in these archaeological deposits reflects the sedimentation history of the littoral cells over ca. 9000 years in the southern bight. Sediment flux to the coast increased markedly in the middle Holocene and led to the development of the modern Oceanside and Silver Strand littoral cells.
Swarming Motility: It Better Be Wet

When grown on a soft agar surface in a rich medium, cells of Salmonella typhimurium elongate, produce extra flagella and move over the surface in a coordinated manner. In mutants with defects in the chemotaxis signaling pathway, the agar plates remain dry and the cells' flagella are short. Recent work shows that the anti-sigma factor controlling late-gene flagellar synthesis is secreted less by flagella when things are dry: the flagellum senses wetness.
Effect of Magnetic Field on Electrode Reactions and Properties of Electrodeposited NiFe Films

Enhancement of current for solutions, containing Ni +2 , Fe +2 , and H + ions, has been observed by linear sweep voltammetry and chronoamperometry when a magnetic field of 0.1 T was applied parallel to the cathode. The current enhancement in a magnetic field was attributed to the convection near the electrode surface induced by the Lorentz force. There is a decrease of the Fe content in NiFe films by approximately 4% obtained with applied magnetic field. It was also demonstrated that the applied magnetic field affects the magnetic properties, crystalline structure and/or texture, stress, and surface roughness of NiFe films.
Derivation of mixing parameters from the HDR-thermal mixing experiments

Abstract This paper presents the results of an analysis and interpretation of mixing phenomena in the cold leg near the injection nozzle during the high-pressure injection (HPI) of cold emergency core cooling water. The mixing efficiency in the injection region governs the temperature transient and the thermal stratification in the cold leg of a PWR. In this analysis the parameters are identified which describe the most important mixing mechanisms. The associated physical models are suitable for application in fast, inexpensive engineering type computer codes to calculate the mixing behaviour and the stratification. Finally, suggestions for improvements of an existing model are made, taking into account available international experimental data.
Applying Grounded Coordination Challenges to Concrete Learning Materials: A Study of Number Line Estimation.

Do concrete learning materials promote strong learning outcomes, or do they simply make learning tasks more initially accessible? Although concrete materials may offer an intuitive foothold on a topic, research on desirable difficulties suggests that more challenging tasks facilitate greater retention and transfer. In the approach introduced here, grounded coordination challenges (GCCs) are embedded into the design of concrete learning materials to deliberately increase the difficulty of the learning task. More specifically, these challenges are intended to promote a deliberative process of mapping between perceptual elements of the materials. In 2 experiments the GCC approach was tested in a number line estimation task by comparing training with an “incongruent ruler”—which was designed to mismatch the length of an on-screen number line—to a “congruent ruler” (both experiments), or no ruler (the 1st experiment only). In both cases participants with the incongruent ruler were more likely to transfer knowledge to spatially transformed number lines. These results indicate that desirable difficulties facilitate learning in mathematical activities. Furthermore, the difficulties should emphasize a deliberate coordination process between critical features of the learning tool and the task. Implications for the design of learning activities that balance instructional support with conceptual challenge are discussed.
Bioremediation : environmental clean-up through pathway engineering

Given the immense risk posed by widespread environmental pollution by inorganic and organic chemicals, novel methods of decontamination and clean-up are required. Owing to the relatively high cost and the non-specificity of conventional techniques, bioremediation is a promising alternative technology for pollutant clean-up. Advances in bioremediation harness molecular, genetic, microbiology, and protein engineering tools and rely on identification of novel metal-sequestering peptides, rational and irrational pathway engineering, and enzyme design. Recent advances have been made for enhanced inorganic chemical remediation and organic chemical degradation using various pathway-engineering approaches and these are discussed in this review.
Three-dimensional through wall imaging using an UWB SAR

UWB radar is superior to the conventional narrowband radar for through wall imaging applications due to its good penetration characteristics, robustness to multipath reflection, and excellent performance in severe clutter environment. A reconfigurable UWB synthetic aperture radar (SAR) was previously implemented to detect/track the real-time position of static/moving targets behind the wall [1]. In this paper, we extend this system into a 3-D imaging radar, which goes beyond targets localization to their shape recognition. The 3-D beamforming algorithm is introduced in details and the performance of the 3-D imaging is validated experimentally using a human mock-up target. The paper is organized as follows. After a brief introduction in section I, the radar transceiver architecture is presented in section II. Section III introduces the 3-D microwave beamforming algorithm while section IV introduces the 3-D imaging experiment. Finally, section V concludes.
Partially depleted SOI MOSFETs under uniaxial tensile strain

The effects of tensile uniaxial strain on the DC performance of partially-depleted silicon-on-insulator n and p-channel MOSFETs as a function of orientation and gate length are reported. The drain current of the n-MOSFETs increases for both longitudinal and transverse strain orientations with respect to the current flow direction. In the n-MOSFET, longitudinal strain provides greater enhancement than transverse strain. In contrast, for p-MOSFETs, longitudinal strain decreases the current while transverse strain increases the drain current. The magnitude of the fractional change in drain current decreases as gate length is reduced from 20 to 0.35 /spl mu/m. These phenomena are consistent with those of bulk silicon MOSFETs and are shown to be qualitatively correlated with the piezoresistance coefficients of the Si inversion layer. Analysis of the linear drain current versus gate voltage characteristics shows that the threshold voltage is independent of strain while the change in drain current tracks with the change in effective electron and hole mobility. Closer examination shows that as the gate length is reduced from 20 to 0.35 /spl mu/m, the relative increase in low-field electron and hole mobility is constant for transverse strain and generally decreases with gate length for longitudinal strain.
Frictions in Polycentric Administration with Non-Congruent Borders: Evidence from Ohio School District Class Sizes

Public managers who operate within cross-jurisdictional governance regimes face substantial difficulties in facilitating network collaboration. Scholars have long suggested that non-congruence of geographic borders can create coordination problems among the political communities within polycentric administrative units. A frequently reoccurring example of such coordination problems arises in cases where municipalities and school districts have non-congruent borders, creating fiscal externalities in residential development land use decisions. Using GIS data from 611 Ohio school districts and 1,585 municipalities in 2000, we calculate the degree of non-congruence between school district and municipal territory to test for evidence that non-congruence of municipal-school district borders influences school district class size. The results indicate that schools with non-congruent borders do experience substantively larger class sizes. Furthermore, these effects seem to increase with the degree of non-congruence. Our findings are robust to model specification and consistent across OLS and treatment effects regression estimates. Policy implications for state-encouraged consolidation of school districts are discussed as well as theoretical and empirical implications of non-congruent jurisdictional borders for governance studies more generally.
Conjugating Methotrexate to magnetite (Fe3O4) nanoparticles via trichloro-s-triazine

Monodisperse Fe3O4nanoparticles (NPs) originally synthesized with a hydrophobic oleylamine capping ligand were made water soluble and conjugated to the anticancer drug Methotrexate (MTX) using a new chemistry based on the readily available linker trichloro-s-triazine (TsT). This new linker is much more versatile than those that currently exist for attaching biomolecules to magnetic NPs. The MTX-conjugated NPs were found to be stable under physiological conditions for over 72 hours and MTX was shown to maintain its anticancer activity after conjugation to the NP surface. Through cell viability studies and intracellular uptake studies, MTX-conjugated NPs were shown to have targeting specificity for a tumor cell line (9L rat glioma) over a healthy cell line (Cultured Pulmonary Artery Endothelial). Additionally the MTX-conjugated NPs were visualized inside 9L cells using fluorescence microscopy to help elucidate their path within a cell after internalization.