cssi/SciSciGPT-SciSciNet huggingface dataset:
GEOMETRIC APPROACHES TO PRODUCE PROLONGATIONS FOR NONLINEAR PARTIAL DIFFERENTIAL EQUATIONS

The prolongation structure of a two-by-two problem is formulated very generally in terms of exterior differential forms on a standard representation of Pauli matrices. The differential system is general without making reference to any specific equation. An integrability condition is provided which gives by construction the equation to be investigated and whose components involve the structure constants of an SU(2) Lie algebra. Along side this, a related, different kind of prolongation, a type of Wahlquist–Estabrook prolongation, over a closed differential ideal is discussed and some applications are given.
Developmental Regulation of Invariant Chain Proteolysis Controls MHC Class II Trafficking in Mouse Dendritic Cells

Dendritic cells (DCs) developmentally regulate their capacity for antigen presentation by controlling the transport and surface expression of MHC class II molecules. These events reflect a developmental regulation of invariant (Ii) chain cleavage, most likely by the cysteine protease cathepsin S. In immature DCs, inefficient Ii chain cleavage due to low cathepsin S activity leads to the transport of class II-Ii chain complexes to lysosomes, while in mature DCs, elevated cathepsin S activity results in efficient delivery of class II alphabeta dimers to the plasma membrane. Cathepsin S is not controlled transcriptionally but by a novel mechanism involving alterations in the expression and localization of an endogenous cathepsin S inhibitor cystatin C. Thus, the ratio of cystatin C to cathepsin S in developing DCs helps to determine the fate of newly synthesized MHC class II molecules.
Fragment atomic-number identification using a gas ionization chamber in fission yield measurements

Abstract A thin-windowed gridded ionization chamber was developed and used with the fission-fragment recoil mass spectrometer HIAWATHA for the direct physical measurement of nuclide yields from fission. The technique developed represents a unique method for the identification of fission fragment atomic mass and atomic number. The sensitivity of the mean energy loss to fragment atomic number and the amount of fragment energy straggling in the chamber gas were measured and gave an atomic-number resolving power of 38 for 95 MeV fragments. Fragment energy losses measured in counter gas P-5 were in good agreement with the Moak-Brown semiempirical method of predicting stopping powers although small systematic discrepancies were found. Fragment energy-loss widths measured in counter gas P-5 were in good agreement with energy loss widths for fragments traversing solid carbon foils.
A magma ocean on Vesta: Core formation and petrogenesis of eucrites and diogenites

Abstract— Available evidence strongly suggests that the HED (howardite, eucrite, diogenite) meteorites are samples of asteroid 4 Vesta. Abundances of the moderately siderophile elements (Ni, Co, Mo, W and P) in the HED mantle indicate that the parent body may have been completely molten during its early history. During cooling of a chondritic composition magma ocean, equilibrium crystallization is fostered by the suspension of crystals in a convecting magma ocean until the crystal fraction reaches a critical value near 0.80, when the convective system freezes and melts segregate from crystals by gravitational forces. The extruded liquids are similar in composition to Main Group and Stannern trend eucrites, and the last pyroxenes to precipitate out of this ocean (before convective lockup) span the compositional range of the diogenites. Subsequent fractional crystallization of a Main Group eucrite liquid, which has been isolated as a body of magma, produces the Nuevo Laredo trend and the cumulate eucrites. The predicted cumulate mineral compositions are in close agreement with phase compositions analyzed in the cumulate eucrites. Thus, eucrites and diogenites are shown to have formed as part of a simple and continuous crystallization sequence starting with a magma ocean environment on an asteroidal size parent body that is consistent with Vesta.
Puerto Rico's Statehood Movement:

Annexationism in Nineteenth Century Puerto Rico The Republican Party, 1898-1924: Advent and Rupture of Annexationism Rupture and Crisis of Annexationism, 1924-1952 The Rise of Postwar Annexationism: From the PER to the PNP, 1952-1968 The New Progressive Party and Politics of Redemption The New Progressive Party and the Politics of Equality Selected Bibliography on the Statehood Movement Index
SU‐E‐T‐601: Optimal Beam Selection for Intensity Modulated Radiation Therapy: High Intensity Flattening‐Filter Free Versus Conventional Flattened Beams

Purpose: To investigate the effect of target size and magnitude of intensity modulation on the required number of monitor units (MU) in IMRT delivered by high intensity flattening filter free (HIFFF) beam. To provide guidelines for the selection of beams that optimizes delivery time. Methods: A 29cm×1cm×5cm target in the center of a 20cm×40cm rectangular phantom was divided into 29 small 1cm×1cm×5cm subtargets along the MLC leaf motion direction. Various sizes of new targets consisting of 5 to 29 subtargets were generated. By prescribing two different doses to adjacent subtargets, the modulation index (MI), defined as the ratio of the nominal dose of the low dose subtargets to that of the high dose subtargets, was varied from 0.2 to 1.0. IMRT plans consisting of simple AP and PA beams were optimized for various combinations of target sizes and MI with 10X HIFFF, 6X HIFFF and 6X flattened beams, respectively. MLC leaf sequences and MUs for delivering 2Gy/fraction were computed using the maximum MU rates of 2400, 1400 and 600 MU/min, respectively. Results: For any combination of target size and MI the 10X HIFFF beam required the highest number of MUs while 6X flattened beam required the lowest. For HIFFF beams, the MU increased with the target size in linear quadratic fashion while decreased approximately linearly with MI. For all tested conditions, 10X HIFFF beam required the shortest delivery time, while 6X beam required 1.4 to 3.7 times as long. Conclusion: Despite its requiring the most MUs among the three beams investigated, the 10X HIFFF beam takes the shortest time to deliver an IMRT plan, regardless of target size and MI. 10X HIFFF beam is the choice of beam for optimal delivery time when increased leaf leakage dose is not a concern.
Further quantification of the sources and sinks of thermospheric O1D) atoms

Abstract In this paper we confirm an earlier finding that the reaction constitutes a major source of OI 6300 A dayglow. The rate coefficient for this reaction is found to be consistent with an auroral result, namely k1 ≈ 6 × 10−12 cm3s−1. We correct an error in an earlier publication and demonstrate that reaction (1) is consistent with the laboratory determined quenching rate for the reaction where k 2 = 2.3 × 10 −11 cm 3 s −1 . Dissociative recombination of O+2 with electrons is found to be a major daytime source in summer above ∼220 km.
Detection of volatile organic compounds by surface enhanced Raman scattering

We present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor is strongly influenced by the substrate temperature, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.
Role of hemoglobin and iron in hydrocephalus after neonatal intraventricular hemorrhage.

Background Neonatal germinal matrix hemorrhage/intraventricular hemorrhage is common and often results in hydrocephalus. The pathogenesis of posthemorrhagic hydrocephalus is not fully understood. Objective To explore the potential role of hemoglobin and iron released after hemorrhage. Methods Artificial cerebrospinal fluid (aCSF), hemoglobin, or iron was injected into the right lateral ventricle of postnatal day-7 Sprague Dawley rats. Ventricle size, heme oxygenase-1 (HO-1) expression, and the presence of iron were evaluated 24 and 72 hours after injection. A subset of animals was treated with an iron chelator (deferoxamine) or vehicle for 24 hours after hemoglobin injection, and ventricle size and cell death were evaluated. Results Intraventricular injection of hemoglobin and iron resulted in ventricular enlargement at 24 hours compared with the injection of aCSF. Protoporphyrin IX, the iron-deficient immediate heme precursor, did not result in ventricular enlargement after injection into the ventricle. HO-1, the enzyme that releases iron from heme, was increased in the hippocampus and cortex of hemoglobin-injected animals at 24 hours compared with aCSF-injected controls. Treatment with an iron chelator, deferoxamine, decreased hemoglobin-induced ventricular enlargement and cell death. Conclusion Intraventricular injection of hemoglobin and iron can induce hydrocephalus. Treatment with an iron chelator reduced hemoglobin-induced ventricular enlargement. This has implications for the pathogenesis and treatment of posthemorrhagic hydrocephalus. Abbreviations aCSF, artificial cerebrospinal fluidDAB, 3,3'-diaminobenzidine-4HClGMH-IVH, germinal matrix hemorrhage/intraventricular hemorrhageHO-1, heme oxygenase-1ICH, intracerebral hemorrhagePBS, phosphate-buffered salineSVZ, subventricular zoneTBST, tris-buffered saline with Tween 20.
Spinal Cord Swelling as a Myelographic Indicator of Prognosis: A Retrospective Study in Dogs With Intervertebral Disc Disease and Loss of Deep Pain Perception

The association of myelographic spinal cord swelling with neurological outcome was examined in 46 dogs with intervertebral disc disease and absence of deep pain perception (DPP). Spinal cord swelling was measured by calculating a ratio of the length of the loss of the myelographic dye column to the length of the second lumbar vertebra (L2). A positive neurological outcome was defined as return of voluntary motor function. A cut-off value for swelling:L2 of 5.0 was established by the creation of a receiver operator characteristic curve. Using a swelling:L2 ratio of 5.0 as a cutoff for indication of neurological recovery yielded a sensitivity of 74% and a specificity of 61%. Overall neurological recovery rate was 43%. Dogs with spinal cord swelling:L2 ratios less than 5.0 had a recovery rate of 61%, whereas dogs with a ratio greater than or equal to 5.0 had a recovery rate of 26%. Evaluation of these data by chi square analysis confirmed that a ratio less than 5.0 was associated with a positive outcome, and a ratio greater than or equal to 5.0 was associated with a negative outcome, (P < .05). Although other factors, such as duration of neurological signs, affect neurological outcome in dogs with no DPP, evaluation of myelographic spinal cord swelling can assist in establishing a prognosis.
3-D particle modeling of gas bubbles in a liquid

Abstract We use a molecular aggregate approach and classical, molecular dynamics type formulas to simulate the motion of gas bubbles within a liquid. For application, the liquid is taken to be water while the gas is taken to be carbon dioxide. The resulting dynamical equations are large systems of second-order, nonlinear, ordinary differential equations which are solved by a time-stepping numerical method. The rise of the bubbles and the motion of the water near the bubbles are described and discussed.
Serial Derotational Casting in Idiopathic and Non-Idiopathic Progressive Early-Onset Scoliosis.

Abstract Introduction Serial derotational casting has been used as a definitive treatment or as delaying strategy in progressive idiopathic (IS) and non-idiopathic (NIS) early-onset scoliosis (EOS). Methods Retrospective chart and radiographic review of patients who underwent serial casting for progressive EOS between 2005 and 2012 at a single institution. Results A total of 74 consecutive patients entered serial cast treatment. Twenty-eight were currently being casted, 30 completed cast treatment and were converted to thoracolumbosacral orthosis (TLSO), 9 were treated surgically, 6 were lost to follow-up, and 1 had no further treatment. The researchers diagnosed IS in 41 patients; 33 had NIS. At presentation the IS group had an average Cobb angle (CA) of 49° and a rib vertebral angle difference (RVAD) of 37°. The NIS group had a CA of 51° (p = .69) and RVAD of 37° (p = .94). In patients currently being casted, 19 IS patients had a decreased CA, from 47° to 27°. The 9 NIS patients had a decreased CA, from 62° to 57° (p = .0002). Cobb angle improvement was significantly better in IS (p = .0005). In the TLSO group the 17 IS patients had a decreased average CA, from 46° to 18°, after serial casting and the 13 NIS patients decreased CA from 42° to 32°. Patients with IS had better improvement in CA than the NIS group (p Conclusions Progressive idiopathic scoliosis patients had better curve correction with casting than NIS patients. Casting in IS patients before age 24 months yielded better curve correction. Patients who required surgery had a higher age and Cobb angle at presentation than those who transitioned to a TLSO. The surgical group was observed for a similar duration of time and there was no significant statistical difference. Although RVAD is a predictor of progression in infantile IS, it did not show a predictive value in the response to casting of either the IS or NIS groups.
Synthesis of Cembranolides by SE′ Cyclization of Enantioenriched α‐Alkoxy Allylstannanes

A total synthesis of the unnamed cembranolide 35 is described starting from enal XV, an intermediate derived from geraniol. Key transformations include asymmetric reduction of stannyl ketone 1 with (R)-(+)-BINAL-H to give the hydroxy stannane 2 of high ee, and cyclization of the derived MOM ether 6 to the cis-(Z) hydroxy enol ether 7 in high yield. Further elaboration of 7 to the natural product was achieved by OH-directed hydroalanation-iodination of the derived diol 17, methylation of iodide 17 with methyl cuprate and selective protection, oxidation, lactonization, and α-methylenation. The resulting product was identified by comparison of 1H NMR, 13C NMR, IR, and optical rotation with an authentic sample. The synthesis defines the absolute configuration of the natural cembranolide.
Computing equilibrium in OLG models with stochastic production

Abstract In this paper we develop a projection algorithm to approximate equilibria in overlapping generations economies with a large number of generations and stochastic aggregate production. In these types of economies the state space includes the distribution of wealth across generations. We use Smolyak's algorithm to approximate policy functions, which map the current state into agents’ optimal choices, by linear combinations of polynomials. This allows us to compute equilibria for models where agents live for 20–30 periods. We also provide examples which demonstrate that approximating the cross-sectional wealth distribution only by its first moment (and thereby reducing the dimension of the state space to two continuous state variable, independently of the number of agents) often leads to very high relative errors in agents’ Euler equations.
Insulin promoted decrease in the phosphorylation of protein synthesis initiation factor eIF-2.

Abstract Insulin stimulates cellular protein synthesis in calf chondrocytes in suspension culture. This enhanced synthetic activity is seen in association with a decrease in phosphorylation of the α subunit of protein synthesis initiation factor eIF-2. [ 32 P] associated with the α subunit is reduced approximately 50% by insulin treatment of chondrocytes incubated in [ 32 P] containing media. Identical or closely located amino acids in the eIF-2 α subunit are phosphorylated by the chondrocyte kinase(s) and the rabbit reticulocyte hemin regulated kinase as indicated by comparative peptide fragment analysis of [ 32 P] labeled α subunits.
Crossing the Red Line: Public Intimacy and National Reputation in Saudi Arabia

In July 2009, the Lebanese Broadcasting Corporation (LBC) aired via satellite an episode of the talkshow Bold Red Line titled “Sexual Pleasure,” in which a Saudi man bragged about his sexual exploits. A wave of protest broke out in Saudi Arabia clamoring for the punishment of the man who would heretofore be known as the “LBC sex braggart.” Saudi authorities brought suit against him and prosecuted two Saudi women who worked for LBC. Drawing on a rich corpus of primary, Arabic-language source—119 articles, most from Saudi newspapers—this article uses the Bold Red Line controversy and Lauren Berlant's work on the “intimate public sphere” to analyze the articulation of patriarchy and nationalism in Saudi public discourse. The controversy, we conclude, reflects how the redefinition of political-economic issues in moral terms depends on an intentional re-articulation of the private-public nexus.
Stable and transient expression of chimeric peroxisomal membrane proteins induces an independent "zippering" of peroxisomes and an endoplasmic reticulum subdomain.

Peroxisomal ascorbate peroxidase (APX) (EC 1.11.1.11) was shown recently to sort through a subdomain of the ER (peroxisomal endoplasmic reticulum; pER), and in certain cases, alter the distribution and/or morphology of peroxisomes and pER when overexpressed transiently in Nicotiana tabacum L. cv. Bright Yellow 2 (BY-2) cells. Our goal was to gain insight into the dynamics of peroxisomal membrane protein sorting by characterizing the structure and formation of reorganized peroxisomes and pER. Specifically, we test directly the hypothesis that the observed phenomenon is due to the oligomerization of cytosol-facing, membrane-bound polypeptides, a process referred to as membrane "zippering". Results from differential detergent permeabilization experiments confirmed that peroxisomal APX is a C-terminal "tail-anchored" (Cmatrix-Ncytosol) membrane protein with a majority of the polypeptide facing the cytosol. Transient expression of several APX chimeras whose passenger polypeptides can form dimers or trimers resulted in the progressive formation of "globular" peroxisomes and circular pER membranes. Stable expression of the trimer-capable fusion protein yielded suspension cultures that reproducibly maintained a high degree of peroxisomal globules but relatively few detectable pER membranes. Electron micrographs revealed that the globules consisted of numerous individual peroxisomes, seemingly in direct contact with other peroxisomes and/or mitochondria. These peroxisomal clusters or aggregates were not observed in cells transiently expressing monomeric versions of APX. These findings indicate that the progressive, independent "zippering" of peroxisomes and pER is due to the post-sorting oligomerization of monomeric, cytosol-facing polypeptides that are integrally inserted into the membranes of "like" organelles. The dynamics of this process are discussed, especially with respect to the involvement of the microtubule cytoskeleton.
Optimal distribution of material properties for an elastic continuum with structure-dependent body force

Abstract The simultaneous optimization of material properties and structural layout for an elastic continuum is formulated and analyzed. The objective is to obtain the maximum structural stiffness for prescribed surface loads and displacements, taking into account a body force that depends on the structural layout. Optimization with an account of self-weight or centrifugal forces are examples of these type of problems. Arbitrary elasticity tensor fields are considered as the problems variable and necessary conditions satisfied by the solution are established. The use of a spectral decomposition of the elasticity tensor is emphasized since it provides a simple geometrical interpretation. Typical examples which illustrate the effects of the structure-dependent body force are analyzed. It is found that a commonly used isoperimetric restriction (known as the resource constraint) is not necessarily active and that the optimal structure is locally stiffer in areas where the body force and the displacement field have opposite directions and locally weaker otherwise. This, interestingly, leads to a non-symmetrical distribution of material properties even for prismatic bodies under anti-symmetric surface loads.
Identification of human α-synuclein specific single chain antibodies

Parkinson's disease (PD) is a common neurodegenerative disease of unknown etiology. Evidence suggests a role for protein misfolding in disease pathogenesis. One pathologic feature observed in dopaminergic neurons is the intracytoplasmic eosinophilic inclusions known as Lewy bodies. One component of Lewy bodies, the presynaptic protein, alpha-synuclein forms oligomers and higher order aggregates and is proposed to be involved in dopaminergic neuronal death. In an effort to discriminate between alpha-synuclein conformational forms as well as design potential disruptors of pathogenic misfolding we panned a human phage antibody library for anti-synuclein single chain antibodies (scFvs). We identified six scFvs which recognize different conformers of alpha-synuclein in both an ELISA and Western blot analysis. These scFvs may further our understanding of alpha-synuclein's role in PD.
Intercrossed Sheet-Like Ga-Doped ZnS Nanostructures with Superb Photocatalytic Actvitiy and Photoresponse

Intercrossed ZnS nanostructures doped with Ga (ZnS:Ga nanowalls) have been synthesized in high yield from mixed powders in a vacuum furnace. ZnS:Ga nanowalls were grown vertically on the substrate with the size in the range of several micrometers and the thickness down to ∼15 nm and have very rough edges. Due to the high surface area and distinctive morphology of ZnS:Ga nanowalls, the photocatalytic activity and the photoresponse show superior properties compared to ZnS:Ga films. The increased conductivity of metal−semiconductor−metal (Ag−ZnS:Ga nanowalls−Ag) Schottky photodetectors under light illumination is attributed to the photogenerated electron−hole pairs, the desorption of oxygen molecules on the ZnS:Ga surface, and the lowering of the Schottky barrier height. The results indicate that ZnS:Ga nanowalls are promising candidate materials for photocatalysts and applicable as photodetectors, optical switches, and sensors in the visible light region.
Step-bunching instability of vicinal surfaces under stress.

On a vicinal surface under stress, elastic relaxation at steps produces a long-range attractive interaction between the steps. As a result, the surface is unstable against step bunching, driven by the energetics of the system rather than by the kinetics of step flow. This bunching instability differs from the predictions of previous continuum models by its lack of a characteristic wavelength. Instead, it evolves by progressive coalescence of step bunches. Flux can dramatically modify this evolution, limiting the growth of step bunches.
Aspects of the Softness and Hardness Concepts of Density‐Functional Theory

In the density-functional theory of the ground state of an electronic system there arise the concepts of softness, hardness, local softness, and local hardness. Definitions of these quantities are reviewed, and then local softness and local hardness are discussed in some detail. The local softness of a species, the derivative , is a measure of the chemical reactivity of a site in the molecule. From it can be obtained the total global absolute softness in the sense of Pearson and a normalized chemical reactivity index of frontier type. Several formulas for s(r) are obtained, including new fluctuation formulas, and its determinative role in chemisorption, catalysis, and frontier-controlled charge-transfer processes is briefly discussed. Local hardness is a corresponding appropriately defined functional derivative η(r) = [δμ/δp(r)]v(r). Difficulties associated with ambiguities in this definition are discussed and resolved. It is concluded that for most purposes the best working formula for local hardness is , where η(r, r′) is the hardness kernel; , where F[p] is the usual Hohenberg-Kohn functional and f(r) is the Fukui function. With this definition, η(r) = η, a constant which is the global hardness. Just as the chemical potential equalizes in the ground state, so does the hardness. It is demonstrated that hardness can be taken to be an average of orbital contributions.
The fine structural development of preimplantation mouse parthenotes.

The normality of the preimplantation development of 2-cell to expanded blastocyst stage mouse parthenotes, derived from oocytes activated in vivo, or in vitro, has been assessed at the fine structural level. Major changes in the organization of the cellular organelles, i.e., nucleoli, mitochondria, ribosomes, RER and junctional complexes, follow the same developmental sequences observed in embryos obtained from normally fertilized oocytes. One difference between parthenotes and controls is the scarcity of crystalloid bodies in parthenotes at the blastocyst stage. Because the embryos examined in this study had been cultured in vitro, in a simple salt and albumin medium in the absence of maternal influences, our observations on parthenotes indicate that developmental, preimplantation changes in the subcellular organization of the embryo do not require the continued presence of "maternal" factors or the participation of the paternal genome.
Antioxidants and endothelium protection

The endothelium is a complex organ system that controls the homeostasis of the vasculature by integrating signals between the vascular wall and the vessel lumen. Under physiological conditions, it maintains a normal vascular tone and blood fluidity by elaborating a variety of factors, such as nitric oxide, prostacyclin and endothelin. However, in pathological situations the endothelium can also modify its phenotype facilitating vasoconstriction, inflammation, and thrombotic events. These abnormal responses manifest in different clinical settings, such as hypercholesterolemia, hypertension, diabetes mellitus, and occur in the absence of any morphological change of the vessel. The etiology of these altered endothelial functions is multi-factorial, and the mechanisms underlying them are complex and not yet fully elucidated. Today, there is substantial evidence that many endothelial functions are sensitive to the presence of reactive oxygen species and subsequent oxidative stress. Here, I will review the increasing number of studies showing that exogenous antioxidants can modulate the endothelium-dependent vasodilation responses, the homeostatic endothelium-leukocyte interactions, the balance between pro- and anti-thrombotic properties, and the vascular apoptotic responses. Finally, the non-antioxidant activities of some antioxidant will also be described.
The impact of Hurricane Andrew on deviant behavior among a multi‐racial/ethnic sample of adolescents in Dade County, Florida: A longitudinal analysis

Findings from a longitudinal study are presented on the relationships between the problems and stresses resulting from Hurricane Andrew and posthurricane minor deviant behavior. The sample (N = 4,978) included Hispanic, African-American, and White non-Hispanic middle school students enrolled in Dade County, Florida public schools. Two waves of data were collected prior to the hurricane; a third was obtained approximately 6 months following the storm. Results indicated that females were likely to report higher levels of hurricane-related stress symptoms than males. After controlling for prehurricane levels of minor deviance, family support, and race/ethnicity, hurricane stress symptom level remained a significant predictor of posthurricane minor deviant behavior. The findings lend support to stress theories of social deviance.
Side effects of reaction media in histochemical blocking procedures.

0.2 N NaOH, the reaction medium for 1,2-cyclohexanedione, a specific reagent for arginyl residues in proteins, was found to intensify, at some sites in rat abdominal skin and human gingiva, the Sakaguchi reaction, staining with Pauly's reagent, and anionic dye binding at pH 6.4; at other sites these reactions were reduced, presumably due to extraction of material from sections. 0.2 N NaOH slightly reduced staining after the ninhydrin-Schiff procedure at all sites in rat skin. The interpretation of this finding is obscure, because some sites giving a positive Sakaguchi reaction and staining with anionic dyes failed to stain after the ninhydrin-Schiff procedure. There were also alterations in staining, with the cationic dyes Alcian Blue and Alcian Yellow. It is suggested that 0.2 N NaOH ruptures linkages between polycationic residues of proteins and polanions, demonstrable by Alican Blue. The blockade produced by acetic anhydride-pyridine (40∶60 v/v) mixtures was stable, in the alkaline conditions required for staining with Pauly's reagent. Pretreatment with pyridine alone reduced tissue binding of anionic dyes.
Many-channel Gel'fand-Levitan equations

Abstract The method of Gel'fand and Levitan for the construction of a spherically symmetric potential in the Schrodinger equation from a spectral function which contains scattering and bound-state data for a single angular momentum state is extended to include the case of n channels coupled by a potential matrix, all of whose elements possess finite first and second absolute moments. The utility of the method for the explicit construction of many-channel S -matrices together with the associated interaction potentials is illustrated by two simple examples.
Design, Implementation, and Evaluation of a Hybrid DS/FFH Spread-Spectrum Radio Transceiver

In recent years there has been great interest in using hybrid spread-spectrum (HSS) techniques for commercial applications, particularly in the Smart Grid, in addition to their inherent uses in military communications. This is because HSS can accommodate high data rates with high link integrity, even in the presence of significant multipath effects and interfering signals. A highly useful form of this transmission technique for many types of command, control, and sensing applications is the specific code-related combination of standard direct-sequence modulation with "fast" frequency-hopping, denoted hybrid DS/FFH, wherein multiple frequency hops occur within a single data-bit time. In this paper, we present the efforts carried out at Oak Ridge National Laboratory toward exploring the design, implementation, and evaluation of a hybrid DS/FFH spread spectrum radio transceiver using a single Field Programmable Gate Array (FPGA). The FPGA allows the various subsystems to quickly communicate with each other and thereby maintain tight synchronization. We also investigate various hopping sequences against robustness to interference and jamming. Experimental results are presented that show the receiver sensitivity, radio data-rate/bit-error evaluations, and jamming and interference rejection capabilities of the implemented hybrid DS/FFH spread spectrum system under widely varying design parameters.
Comparison of the Lithoclast Ultra and Cyberwand in a cystolitholapaxy model

The Lithoclast Ultra (R) combines ultrasonic and pneumatic lithotripsy with a single handpiece, while the Cyberwand (R) combines two concentric ultrasonic lithotrites. We tested each device in a cystolitholapaxy model. An ex vivo bladder model was constructed. The test stones used were the Bego and U-30. For the Lithoclast Ultra, 10 trials of each stone type were performed. The ultrasound was tested at 90% duty and 100% power and the pneumatic tested at 12Hz. For the Cyberwand, the 'Large' stone and 'Small' stone setting were tested. Twenty trials with the U-30 stone were performed at each setting. Only 1 Bego stone finished Cyberwand testing. The time to clear all stone fragments was recorded. For the U-30 stones, the total time to stone clearance was 127 seconds for the Lithoclast Ultra, 41 seconds for the Cyberwand (Large setting) (p=0.001), and 69 seconds for the Cyberwand (Small setting)(p=0.12). For the Bego stones, the time to 5mm fragments and the total time to stone clearance was 14 and 22 minutes for the Lithoclast Ultra. The Cyberwand probe failed repeatedly during Bego stone testing. Four probes were required to completely eliminate a single Bego stone. For the softer U-30 stones, the Cyberwand time to stone clearance was significantly faster than the Lithoclast Ultra (p<0.05). For the harder Bego stones, the Cyberwand was not able to complete the trial due to repeated probe failure, and was outperformed by the Lithoclast Ultra.
Living Globorotalia menardii (d'Orbigny) forma neoflexuosa from the eastern tropical Pacific Ocean

Abstract Two vertical net tows (0 to 200 m) from the eastern tropical Pacific Ocean show foraminiferal assemblages dominated by Globoratalia menardii (d'Orbigny). Significant numbers of flexuose and aberrant forms were found within the population of G. menardii . Recent occurrences of flexuose forms of G. menardii in areas of upwelling and in association with aberrant specimens suggest that this form is ecologically controlled and does not represent a true genetically definable subspecies: it should, therefore, be referred to as Globorotalia menardii forma neoflexuosa .
Incorporation of inorganic phosphate-32 into a Na+, K+-ATPase preparation: stimulation by ouabain.

Abstract A Na + , K + -ATPase preparation isolated from calf brain (and possessing moderate activity) was labeled with inorganic 32 phosphate ( 32 P i ) in the presence of Mg 2+ plus K + . The incorporation of 32 P i was doubled in the presence of ouabain (0.1 m m ). Using an enzyme system of greater purity, significant labeling with 32 P i occurred only in the presence of Mg 2+ , K + plus ouabain and was dependent on the concentration of inorganic phosphate. Elution of the protein hydrolysates from a Dowex 50 H + column showed that the fraction labeled in the presence of 32 P i was similar to that found when AT 32 P was employed. The data suggest a phosphate and/or ouabain-induced conformational change of the enzyme system.
Streptomycin-resistant and streptomycin-dependent mutants of the extreme thermophile Thermus thermophilus.

We have isolated spontaneous streptomycin-resistant, streptomycin-dependent and streptomycin-pseudo-dependent mutants of the thermophilic bacterium Thermus thermophilus IB-21. All mutant phenotypes were found to result from single amino acid substitutions located in the rpsL gene encoding ribosomal protein S12. Spontaneous suppressors of streptomycin dependence were also readily isolated. Thermus rpsL mutations were found to be very similar to rpsL mutations identified in mesophilic organisms. This similarity affords greater confidence in the utility of the crystal structures of Thermus ribosomes to interpret biochemical and genetic data obtained with Escherichia coli ribosomes. In the X-ray crystal structure of the T. thermophilus HB8 30 S subunit, the mutated residues are located in close proximity to one another and to helices 18, 27 and 44 of 16 S rRNA. X-ray crystallographic analysis of ribosomes from streptomycin-resistant, streptomycin-pseudo-dependent and streptomycin-dependent mutants described here is expected to reveal fundamental insights into the mechanism of tRNA selection, translocation, and conformational dynamics of the ribosome.
STUDENTS’ UNDERSTANDING OF LARGE NUMBERS AS A KEY FACTOR IN THEIR UNDERSTANDING OF GEOLOGIC TIME

An understanding of geologic time is comprised of 2 facets. Events in Earth’s history can be placed in relative and absolute temporal succession on a vast timescale. Rates of geologic processes vary widely, and some occur over time periods well outside human experience. Several factors likely contribute to an understanding of geologic time, one of which is an individual’s ability to perceive the relative size of large time periods and to move multiplicatively through quantities that differ by many orders of magnitude. Thirty-five US students aged 13–24 years participated in task-based interviews to assess their understanding of large temporal periods. Fewer than half of the students performed well enough to indicate that their knowledge of large numbers was robust enough to enable them to understand processes in geologic time. Some students were confused about relationships between quantities in the thousands and millions, while others had difficulty showing proportional relationships among relatively small temporal units (up to 100 years). Students differed in their ability to perceive the entire scale upon which numbers were to be placed as well as broader problem-solving strategies. Spatial mapping of numbers was evident. Implications for future research are discussed.
Having it all? Combining work and family in a male and a female profession

Are women in a female-dominated profession more successfully able to combine work and family obligations than women in a male-dominated profession? To explore this question, a comparison was made between the family status and careers of 747 women librarians (a female-dominated profession) and those of 449 women MBAs (a male-dominated profession). It was expected that the librarians would marry earlier and have more children. This general prediction was not supported. Over half of both groups of women were married, and after controlling for age, there were no differences in number of children. However, many women without children in both groups reported that they would like to be mothers. This disparity between wanting children and not having them was more common for women MBAs than women MLSs. MBAs and librarians were about equally likely to have had job interruptions, but librarians were more likely to have worked part-time. Reasons for an interruption to full-time work were as likely to be for problems finding (full-time) work as for family responsibilities. Librarians' salaries were much lower, but job interruptions and part-time work had a more negative effect on the salaries of women in business. In sum, the data suggest that many of the women surveyed have not combined motherhood with a professional career and that it is probably somewhat more difficult to combine a family with a career in business than with a career in library science.
A Versatile Solderless Electrode Carrier

St~mmary.-An electrode connector for chronic brain implants can be inexpensively assembled from small commercial plastic strips, pre-drilled to accept miniature crimp contacts. Strips can be cut to any length with pliers and cemented together in various versatile Corms. Crimps are easily applied to elec- trodes before surgery and inserted into strips during surgery. Twelve or more electrodes on a rat's skull are feasible. any number (within the obvious limit of the animal's head size) of electrodes in any shape and array desired. The basic struccural unit or module is com- mercially available%nd inexpensive. Other outstanding advantages include preparation of the entire assembly prior to surgery, simple and reliable crimp contacts which eliminate the hazards of soldering, and low noise connection to remote equipment. All these features apply as well ro the external male con- nector assembly used to join the preparation to stimulation or recording equip- ment. The basic assembly in several forms is shown at the lower right of Fig. 1. The female (implanted) connector with two bipolar pairs of electrodes inserted is shown in the center, with the male external connector immediately above. (The 5th contact is used for skull ground.) Shown to the right is a single bipolar pair with crimps attached for insertion into the connector modules as shown in different lengths at the extreme left and right. Once these wires are stereotactically implanted, the crimps are pressed into the phenolic strips with a hemostat and the entire assembly is immediately ready to attach to the skull. The latter is easily accomplished by a tripod-arrangement of skull stainless 'This research was supported by Public Health Service Research Grant No. MH-05207 to Dr. 0. T. Law from the National Institutes of Health. -Amphenol-Borg Electronic brp., 5426 Reseda, Tarzana, Calif.
Convergence of Min-Sum Message Passing for Quadratic Optimization

We establish the convergence of the min-sum message passing algorithm for minimization of a quadratic objective function given a convex decomposition. Our results also apply to the equivalent problem of the convergence of Gaussian belief propagation.
Evolution of Membrane Leakage by Pre-Amyloidogenic Oligomers of Islet Amyloid Polypeptide

Islet amyloid polypeptide (IAPP) is the primary amyloid component found in patients suffering from type II diabetes. IAPP has been implicated in the death of pancreatic beta-cells, resulting in a greater strain on the remaining insulin producing cells and contributing to further progression of the disease. While fibers are the most obvious characteristic of any amyloid disease, it has been found that smaller soluble oligomers are the most likely source of cytotoxicity. Previous research has shown that IAPP oligomers are capable of permeabilizing lipid bilayers under physiological conditions. Permeabilization of cellular membranes resulting in ionic imbalance and subsequent apoptosis is a leading theory for the cause of beta-cell death in type II diabetes. In order to better understand the mechanism by which IAPP causes cell death we have examined the evolution of membrane-bound leakage states over time. Using a combination of bulk and single molecule techniques we have uncovered a multi-phasic leakage mechanism in which we observe two clear time regimes of leakage behavior induced by soluble pre-amyloidogenic oligomers. Our results give us further insight into the mechanism by which IAPP is capable of inducing membrane leakage.
Linguistic techniques of the self: The intertextual language of racial empowerment in politically conscious Brazilian hip hop

Abstract This article describes the bodily aesthetics, patterns of consumption, and daily linguistic practices undertaken by hip-hop affiliated youth in Rio de Janeiro in the late 1990s. I argue that through their participation in politically conscious hip hop, poor male Brazilian youth attempt to racially transform their bodies into a form of ‘modern blackness.’ I focus, in particular, on the quoting of rap lyrics in daily conversation, a linguistic practice that offers audible evidence of one’s consumption of hip hop style. I suggest that linguistic strategies of racial empowerment constitute forms of ‘techniques of the self’ that allow speakers to manage the racial appearance of the body through an avoidance of the traits that are negatively associated with blackness in Brazil.
Effects of cationic polypeptides on the activity, substrate interaction, and autophosphorylation of casein kinase II: A study with calmodulin

Abstract The effects of basic polypeptides on the ability of casein kinase II to phosphorylate an exogenous substrate (calmodulin) are correlated with steady-state autophosphorylation of the α- and β-subunits of casein kinase II. Polylysine and polyarginine increase autophosphorylation of the α-subunit with a concomitant decrease in β-subunit phosphorylation, while enhancing casein kinase II-stimulated phosphorylation of calmodulin over 100-fold. The highly basic carboxyl terminal segment of the endogenous p21c-Ki-ras has similar effects on the phosphorylation of calmodulin and the α- and β-subunits of casein kinase II. Altering the concentration of cationic polypeptides produces a biphasic effect on the phosphorylation of both calmodulin and the α-subunit, which correlate positively with each other but do not correlate with β-subunit phosphorylation. When the KCl concentration is changed, casein kinase II activity correlates positively only with α-subunit phosphorylation. In contrast, the biphasic response of calmodulin phosphorylation by casein kinase II at different Ca2+ concentrations correlates positively with both α- and β-subunit phosphorylation. Therefore, in the presence of basic protein activators, the rate of phosphorylation of a substrate, calmodulin, correlates with steady-state phosphorylation of the α-subunit, but not with the β-subunit under all conditions tested. Endogenous cationic factors may modulate the in vivo activity of casein kinase II and alter the interaction of the enzyme with specific intracellular substrates.
Long-Acting Forms of Growth Hormone-Releasing Hormone and Growth Hormone: Effects in Normal Volunteers and Adults with Growth Hormone Deficiency

Background: Growth hormone (GH) replacement therapy in adults and children has found broad acceptance by endocrinologists and patients, but the need for daily injections remains a s
Transient loss of dopamine autoreceptor control in the presence of highly potent dopamine agonists

The concentrations of endogenous ligands generally remain in a bounded range around a basal level, a manifestation of control. The dopaminergic system is an excellent example of a control system in which a negative feedback signal is associated with receptor occupancy of a D2-like dopamine autoreceptor. A consequence of the control theory is that autoreceptor occupancy by an agonist results in dopamine levels below the basal, whereas similar stimulation by a dopamine competitive antagonist results in an increase of dopamine to levels above the basal. These consequences of control theory were tested and verified in the rat striatum by infusing graded doses of either the agonist, quinpirole, or the antagonist, sulpiride, into the rat striatum via a microdialysis probe and sampling dopamine and metabolite levels at various times after the start of infusion. Control was maintained even at the very highest doses of these compounds, i.e., striatal dopamine concentration rose in response to the antagonist and fell in response to the agonist. In contrast, administration of each of two high affinity dopamine agonists, 7-OH-DPAT and PPHT showed dose-dependent control only up to certain doses. Above these doses the dopamine concentration actually increased to levels well above basal, an indication of loss of control. These findings suggest that the control of this endogenous ligand does not extend to the very highest levels of autoreceptor occupancy.
Detecting wormhole attacks in delay-tolerant networks [Security and Privacy in Emerging Wireless Networks]

Delay-tolerant networks are especially useful in providing mission-critical services including emergency scenarios and battlefield applications. However, DTNs are vulnerable to wormhole attacks, in which a malicious node records the packets at one location and tunnels them to another colluding node, which relays them locally into the network. Wormhole attacks are a severe threat to normal network operation in DTNs. In this article we describe various methods that have been developed to detect wormhole attacks. However, most of them cannot work efficiently in DTNs. To detect the presence of a wormhole attack, we propose a detection mechanism that exploits the existence of a forbidden topology in the network. We evaluated our approach through extensive simulations using both Random Way Point and Zebranet mobility models. Our results show that the proposed method can detect wormhole attacks efficiently and effectively in DTNs.
Multi-tiered control for undergraduate mechatronics

As mechatronics has gained popularity, the use of more sophisticated control in the design of computer controlled systems has also increased. It is reasonable to teach mechatronics using a gradually increasing complexity in control approach, beginning with discrete and combinational logic and progressing to error feedback control. This work presents an overview of the controls taught in the mechatronics course at Iowa State University and focuses on the introduction of control concepts appropriate for undergraduate mechanical engineers.