cssi/SciSciGPT-SciSciNet huggingface dataset:
CHAPTER 4 – Hydrogen Atom

Publisher Summary The hydrogen atom has only one electron. The wave function ψ(r) of the electron in the hydrogen atom satisfies the Schrodinger equation. The hydrogen atom consists of a proton and an electron, and has a spherical symmetry that can most easily be studied using a spherical polar coordinate frame. Although the energy of an electron in a hydrogen atom can be specified by giving the quantum number n, the motion of an electron moving in three dimensions is not completely specified by giving the value of its energy. Levels of the hydrogen atom illustrate correspondence to definite values of n and l. For each choice of n and l, there are 2l+1 values of ml and two values of ms. Each level corresponds to a total of 4l + 2 different sets of quantum numbers. An energy level that corresponds to a number of independent states is said to be degenerate. Using this terminology, the energy levels of the hydrogen atom may be said to be (4l + 2)-fold degenerate. The stationary states represent the possible ways the state of the hydrogen atom can evolve in a constant external field at a particular time t. The chapter also studies interaction of the hydrogen atom with an external magnetic Field.
2108-P: Complex Posttranslational Processing of Glucagon Prohormone in Human Pancreatic Islets

An array of signaling peptides and peptide hormones in pancreatic islets results from posttranslational processing of precursor proteins by well-characterized endopeptidases. While the encoded peptide complement can be predicted in silico from the prohormone sequence, actual peptide products often are more diverse due to additional chemical or enzymatic modifications of mature predicted peptides. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for comprehensive molecular characterization, we compiled an experimentally deduced database of endogenous peptides in human pancreatic islets and revealed an unexpected complex processing of several prohormones including proglucagon. Live pancreatic islets from several donors were provided by the Human Pancreas Analysis Program, University of Pennsylvania. Total of 2034 chemically unique peptide sequences were identified and matched to 477 proteins in the human protein database. Among interesting observations, we find differential cleavage of the signal peptide on the glucagon precursor protein, NP_002045.1, and unusual further processing of its encoded mature peptides. Alternate signal peptide cleavage sites are confirmed by detection of both classical GRPP, R[21]-D[50], and its novel variant S[18]-D[50]. An amidated IP-2 D[131]-L[142] and an isoform of MPGF D[131]-D[178], missing the GLP-1 sequence were detected. Previously unreported N-terminus acetylation of glucagon, GLP-1, GLP-1 (7-36), and oxyntomodulin was detected. Novel peptides potentially resulted from variable processing of mature glucagon, GRPP, and oxyntomodulin at internal convention cleavage sites were characterized. New chemically unique peptides originating from proglucagon and documented in this study indicate a more complex posttranslational processing of proglucagon in human islets than previously thought. The finding expands opportunity for mechanistic studies on pathology, progression, and treatments of diabetes. Disclosure E.V. Romanova: None. S. Rubakhin: None. J.V. Sweedler: None. Funding American Diabetes Association/Pathway to Stop Diabetes (1-18-VSN-19 to J.V.S.)
Raman spectroscopic analysis of model solid rocket propellant for the detection of stabilizer decay

The primary objective of this effort is to demonstrate the efficacy of the Raman spectroscopy technique for detecting and evaluating the health of propellant stabilizers commonly used in missiles stored under a range of ambient conditions. Tincured silicone rubber doped with a commonly used propellant stabilizer N-methyl-4-nitroaniline (MNA) and ammonium nitrates used in explosives has been investigated using 532 nm and 785 nm wavelength laser Raman systems. The detected propellants’ Raman peak intensity ratios are used to analyze the results. Calibration curves with error bars are created using more than 30 data runs. The results indicate both systems are suitable to detect fractions of these chemicals as low as 0.2 percent within a few seconds of integration time. The calibration curves created for all the samples measured show a consistent linear increase to the ratio indicating the reliability of the measurements.
Management of Pulmonary Hypertension in the Pediatric Patient.

Pediatric pulmonary hypertension (PH) is a rare disease with historically very high morbidity and mortality. In the past 20 years, there has been a growing recognition that pediatric PH, although having similarities to adult PH, is a unique entity with its own particular pathogeneses, presentation, and management. With better understanding and earlier diagnosis of pediatric PH, and as more medications have become available, survival of children with PH has also significantly improved. This article reviews the various forms of PH in childhood, with a focus on both established and investigational therapies that are available for children with PH.
Isolation of anaerobic bacteria from human gingiva and mouse cecum by means of a simplified glove box procedure.

An anaerobic glove box constructed of clear flexible vinyl plastic is described. It is sufficiently inexpensive and simple in operation to be used not only in research but also in a clinical laboratory by technicians without special training. Conventional bacteriological techniques may be used inside the glove box for culturing and transferring anaerobic bacteria. The box may be heated to 37 C and thus serve as an anaerobic incubator as well, permitting inspection of cultures at any time. Media may be prepared and agar plates may be poured on the laboratory bench in the conventional manner. An overlay of trace amounts of palladium black catalyst over plated agar media reduces the medium to an oxidation-reduction (O-R) potential of - 300 mv within 2 days after introduction into the glove box. In spite of its greater simplicity, the system matched or excelled the roll tube method with respect to all parameters tested, including O-R potential obtainable in the media, O2 concentration in the gas phase, and efficiency in isolating anaerobic bacteria from the mouse cecum. Comparative studies indicate that the conventional anaerobic jar method was inadequate for the isolation of strict anaerobes from human gingival specimens and from the mouse cecum. This was due to the exposure of specimens and media to air during plating on the open laboratory bench. Anaerobic jars were adequate for maintaining the proper conditions for growth of anaerobic bacteria once these had been established in the glove box. Images
Is the cerebellum sensory for motor's sake, or motor for sensory's sake: the view from the whiskers of a rat?

Publisher Summary This chapter describes a new theory of cerebellar function, which posits that the cerebellum is specifically involved in monitoring and adjusting the acquisition of most of the sensory data on which the rest of the nervous system depends. If correct, the cerebellum is not itself responsible for any particular behaviorally related function but instead facilitates the efficiency with which other structures perform their own functions. In this way the cerebellum may, in fact, be useful but not necessary for brain function as a whole. The idea that the cerebellum controls sensory data acquisition has emerged over the past years from the detailed study of a very small region of crus IIA in the lateral hemispheres of the cerebellum of the albino rat. Perhaps the best evidence that the cerebellum is involved in sensory data acquisition control is its involvement in eye movements system. By definition, anything affecting the position of the eyes is directly related to sensory data acquisition, as acquiring visual data is the only thing an animal does with its eyes.
Molecularly imprinted organic transistor-based sensor for selective trace chemical vapor detection

We report a vapor phase molecular imprinting (MIP) technique suitable for an organic field-effect transistors (OFET)-based sensor. This OFET-based sensor using pentacene as the molecularly imprinted monomer showed enhanced selectivity to 2, 4-dinitrotoluene (DNT) vapor against various interfering analytes. This method can be extended to improve the selectivity of most OFET- and chem-resistor based sensors without adversely affecting the device's electronic properties, which is promising for the development of highly selective, low-cost, flexible OFET sensors.
Differences in the response of normal and transformed BHK21 cells to dual virus infection. Conditions affecting synergism between vesicular stomatitis virus and newcastle disease virus.

Abstract Polyoma-transformed BHK21 cells were less sensitive than untransformed BHK21 cells to plaque production by vesicular stomatitis virus (VSV) although neither the adsorption of the input virus to transformed cells nor the burst size were found to be reduced. Infection of either cell type with an avirulent strain (BI) of Newcastle disease virus (NDV) resulted in only a single cycle of noninfectious NDV hemagglutinin production. Neither BHK21 cells nor a polyoma-transformed clonal derivative (Cl-I) produced detectable interferon in response to NDV infection. On the contrary, dual infection with NDV and VSV resulted in a paradoxical enhancement of VSV plaque number and size in Cl-I but not in BHK21 cells. The degree of synergism was affected by the density of Cl-I cell cultures, by NDV multiplicity, and by the time interval between NDV and VSV infection. These findings suggest that alteration of cell functions affecting cellular sensitivity to single (VSV) and also dual (NDV-VSV) infection may be associated with the virus-transformed state.
Immunity to Fungi

The medically important fungi are a diverse group of pathogens that employ a variety of virulence strategies to establish themselves in the host. Successful host defence against fungi requires collaboration between innate and acquired humoral and cellular immune mechanisms. Keywords: immunity; immune system; neutrophil; lymphocytes; macrophage; fungus; yeast; opportunistic; humoral immunity; cellular immunity
The Politics of Participation

Standard models of political participation emphasize the role of factors largely external to politics, such as socioeconomic status and personal characteristics, but “political activity also has its roots in political issues and conflicts. [W]hat happens in politics has implications for who is active in politics” (Verba, Schlozman, and Brady 1995, 415). What are the characteristics of citizens’ reactions to policy outcomes and the differential effects of these reactions on participation? Despite the clear importance of this question for democratic accountability, we know preciously little about its answer. We seek to shed light on this important antecedent of political participation – one strongly implied by prior work, but rarely examined with any level of rigor. We find that citizens invited to think about a public policy display a greater intent to participate in political activities, particularly those who have strong reactions to the policy and those who disagree with the policy. Positive emotions and evidence of self-interest are prevalent among those who strongly agree with policies, while positive and negative emotions are commonly observed among those who disagree strongly with a policy, and no evidence of self-interest. Finally, the effect of policy disagreement on participation is especially high among individuals who respond emotionally to policy, particularly those who are angry or afraid, while those who judge themselves worse off based on a policy participate less.
Stock Repurchase and Cash Acquisition - A Payout Policy Perspective

We examine a firm's repurchase and acquisition decision in a cash payout framework with a focus on the interaction between corporate finance and governance. A comparison of repurchase and acquisition gives us a unique perspective in a sense that they both deal with the question of how to expend cash in a hierarchy of spending priorities that involve decisions not only about payout policy but also on investment strategies. Ours is the first empirical study to investigate a possible pecking order among a set of cash spending options as recently documented in a field survey of financial executives. We find evidence that both repurchase and acquisition will not be considered until cash requirements of internal investment, dividend payout and debt reduction have been satisfied. Furthermore, repurchase is of secondary importance to acquisition in that the former is usually initiated only after substantial amount of cash are accumulated while the latter can be prompted when strong free cash flow starts to generate. This also points to the observation that repurchase firms are often bigger with more cash, better operating performance and low debt, signs of firms that are in later stages of the life cycle. Our results from the study of repurchase in conjunction with cash acquisitions prove to be particularly enlightening in the context of free cash flow hypothesis (Jensen 1986). We conjecture that managers are prone to wasting free cash on acquisitions when cash flow is strong and it is only when cash stock begins to pile up that they are thinking about paying back extra cash to shareholders. This is a strong version of free cash problem as originally pointed out by Jensen. To mitigate the agency problem as manifested by value destroying acquisitions and facilitate repurchase as a way of giving value back to shareholders, the classic theories that propose more management ownership and advocate greater role of institution monitoring seem to be supported in our empirical exercises. Our event study results buttress the assumption that repurchase is more value enhancing than acquisition in that it may alleviate the agency problem of free cash flow.
CHEMICAL COMPOSITION OF BLACK ROCKFISH (SEBASTES MELANOPS) FILLETS AND BYPRODUCTS

Black rockfish are important in the near shore fishery of Southeast Alaska, being the only species among the pelagic shelf rockfishes with a directed fishery in State waters. The purpose of this study was to determine the composition of black rockfish fillets, heads and livers. Fillet yields were low at 13.7% of whole fish weight (WFW), while heads and livers composed 24.8 and 1.9% of WFW, respectively. Byproducts were a valuable source of lipids, and the marine oils extracted from these tissues were similar in many aspects to oils from other cold water marine finfish, being rich in omega-3 and low in omega-6 fatty acids. Protein content of fillets, heads and livers were within the expected range (15–20%). Amino acid analysis revealed that byproducts protein fractions were of high nutritional value. Results indicated that these byproducts have value and could be further processed into protein powders, fishmeal and fish oils. PRACTICAL APPLICATIONS This research is part of an ongoing effort to increase the value of Alaska fisheries by promoting entire utilization of the catch. There is opportunity to improve utilization of fisheries' byproducts by converting these materials into fishmeal, fish oils and protein powders that can either be used as ingredients for the manufacturing of feed further purified for food applications.
An Automated Technique for Measuring δD and δ18O Values of Porewater by Direct CO2 and H2 Equilibration

The stable-oxygen and -hydrogen isotopic values (deltaD, delta18O) of porewater in geologic media are commonly determined on water obtained by extraction techniques such as centrifugation, mechanical squeezing, vacuum heating and cryogenic microdistillation, and azeotropic distillation. Each of these techniques may cause isotopic fractionation as part the extraction process and each is laborious. Here we demonstrate a new approach to obtain automated, high-precision deltaD and delta18O measurements of porewater in geologic sediments by direct H2- and CO2-porewater equilibration using a modified commercial CO2-water equilibrator. This technique provides an important and cost-effective improvement over current extraction methods, because many samples can be rapidly analyzed with minimal handling, thereby reducing errors and potential for isotopic fractionation. The precision and accuracy of direct H2- and CO2-porewater equilibration is comparable to or better than current porewater extraction methods. Finally, the direct equilibration technique allows investigators to obtain high-resolution (cm scale) porewater deltaD and delta18O profiles using cores from individual boreholes, eliminating the need for costly piezometers or conventional porewater extractions.
Upper-level physics students’ conceptions of understanding

As part of a larger study into upper-level physics student identity development that is currently underway students were questioned about their conception of understanding. Contained with this paper are the results for students’ conceptions of understanding which correlate significantly to those found by Waterhouse and Prosser [2]. However, having carried out pilot interviews of the interview protocol used to examine identity and cognitive development, the researchers noticed a large frequency in the amount of students that indicated their conception of understanding to be “when you can explain it to others or yourself.” This prompted a further examination of this conception of understanding via phenomenographic interview and analysis.
Multifactor controls on terrestrial N 2 O flux over North America from 1979 through 2010

Abstract. Nitrous oxide (N2O) is a potent greenhouse gas which also contributes to the depletion of stratospheric ozone (O3). However, the magnitude and underlying mechanisms for the spatiotemporal variations in the terrestrial sources of N2O are still far from certain. Using a process-based ecosystem model (DLEM – the Dynamic Land Ecosystem Model) driven by multiple global change factors, including climate variability, nitrogen (N) deposition, rising atmospheric carbon dioxide (CO2), tropospheric O3 pollution, N fertilizer application, and land conversion, this study examined the spatial and temporal variations in terrestrial N2O flux over North America and further attributed these variations to various driving factors. From 1979 to 2010, the North America cumulatively emitted 53.9 ± 0.9 Tg N2O-N (1 Tg = 1012 g), of which global change factors contributed 2.4 ± 0.9 Tg N2O-N, and baseline emission contributed 51.5 ± 0.6 Tg N2O-N. Climate variability, N deposition, O3 pollution, N fertilizer application, and land conversion increased N2O emission while the elevated atmospheric CO2 posed opposite effect at continental level; the interactive effect among multiple factors enhanced N2O emission over the past 32 yr. N input, including N fertilizer application in cropland and N deposition, and multi-factor interaction dominated the increases in N2O emission at continental level. At country level, N fertilizer application and multi-factor interaction made large contribution to N2O emission increase in the United States of America (USA). The climate variability dominated the increase in N2O emission from Canada. N inputs and multiple factors interaction made large contribution to the increases in N2O emission from Mexico. Central and southeastern parts of the North America – including central Canada, central USA, southeastern USA, and all of Mexico – experienced increases in N2O emission from 1979 to 2010. The fact that climate variability and multi-factor interaction largely controlled the inter-annual variations in terrestrial N2O emission at both continental and country levels indicate that projected changes in the global climate system may substantially alter the regime of N2O emission from terrestrial ecosystems during the 21st century. Our study also showed that the interactive effect among global change factors may significantly affect N2O flux, and more field experiments involving multiple factors are urgently needed.
Characterization of thin poly(dimethylsiloxane)-based tissue-simulating phantoms with tunable reduced scattering and absorption coefficients at visible and near-infrared wavelengths

Optical phantoms are used in the development of various imaging systems. For certain applications, the development of thin phantoms that simulate the physical size and optical properties of tissue is important. Here, we demonstrate a method for producing thin phantom layers with tunable optical properties using poly (dimethylsiloxane) (PDMS) as a substrate material. The thickness of each layer (between 115 and 880 μm) was controlled using a spin coater. The reduced scattering and absorption coefficients were controlled using titanium dioxide and alcohol-soluble nigrosin, respectively. These optical coefficients were quantified at six discrete wavelengths (591, 631, 659, 691, 731, and 851 nm) at varying concentrations of titanium dioxide and nigrosin using spatial frequency domain imaging. From the presented data, we provide lookup tables to determine the appropriate concentrations of scattering and absorbing agents to be used in the design of PDMS-based phan- toms with specific optical coefficients. In addition, heterogeneous phantoms mimicking the layered features of certain tissue types may be fabricated from multiple stacked layers, each with custom optical properties. These thin, tunable PDMS optical phantoms can simulate many tissue types and have broad imaging calibration appli- cations in endoscopy, diffuse optical spectroscopic imaging, and optical coherence tomography, etc.©The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full
Disulfide-Crosslinked Polyion Micelles for Delivery of Protein Therapeutics

New protein delivery systems are needed that efficiently encapsulate proteins and avoid formulation processes that affect protein structure and function. We have developed a protein delivery system termed disulfide-crosslinked polyion micelles (DCPMs), which consist of nanocomplexes formed by electrostatic self-assembly of a protein with a poly(ethylene glycol)-poly(l-lysine) block copolymer (PEG-PLL). The PEG-PLL amines are modified with crosslinkable dithiopyridine groups, using a Michael addition reaction that preserves the positive charges on the PLL chain to optimize polyionic complexation and disulfide crosslinking. DCPMs for vaccine delivery were prepared with ovalbumin and immunostimulatory CpG-DNA and are designed to release the vaccine intracellularly through reduction of disulfide crosslinks. DCPMs were also developed as a long-circulating enzyme carrier that maintains the enzymatic activity of the anti-oxidant enzyme catalase within the micelle core. Ovalbumin and catalase were each modified with SPDP to tether the protein in the micelle core, resulting in a high degree of protein retention under SDS-PAGE. DCPMs efficiently encapsulate and retain functional proteins in a stable polyionic complex and are a versatile delivery system for enzymes, vaccine antigens, and other protein therapeutics.
Numerical model study of radio frequency vessel sealing thermodynamics

Several clinically successful clinical radio frequency vessel-sealing devices are currently available. The dominant thermodynamic principles at work involve tissue water vaporization processes. It is necessary to thermally denature vessel collagen, elastin and their adherent proteins to achieve a successful fusion. Collagens denature at middle temperatures, between about 60 and 90 C depending on heating time and rate. Elastin, and its adherent proteins, are more thermally robust, and require temperatures in excess of the boiling point of water at atmospheric pressure to thermally fuse. Rapid boiling at low apposition pressures leads to steam vacuole formation, brittle tissue remnants and frequently to substantial disruption in the vessel wall, particularly in high elastin-content arteries. High apposition pressures substantially increase the equilibrium boiling point of tissue water and are necessary to ensure a high probability of a successful seal. The FDM numerical models illustrate the beneficial effects of high apposition pressures.
Characterisation of the T-region of the SAP-type Ti-plasmid pTiAT181: identification of a gene involved in SAP synthesis

The T-region of pTiAT181, a SAP(succinamopine)-type Ti-plasmid, is described and is found to be similar to that of the nopaline-type pTiT37. The two major differences are a deletion of 2.9 kb inside the left hand end of pTiAT181, and a right hand region comprised of DNA specific to pTiAT181. This novel DNA was shown by its transfer to plants using a binary vector, to encode an enzyme involved in the synthesis of SAP.
Molecular weight dependence of the physical properties of protonated polyaniline films and fibers

Polyaniline, (PANI) in the form of emeraldine base, was synthesized by polymerizing aniline in acid solutions at different sub-zero temperatures to give a range of molecular weights between 100,000 and 300,000 gmol-1. Molecular weights were measured using gel permeation chromatography (GPC). The polymers were formed into solvent-cast films using an acid processing technique, involving 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA) as the solvating/protonating acid group and dichloroacetic acid (DCA) plus formic acid (FA) as the solvent. The dried, free-standing films were stretched by drawing over a hot pin to align the polymer chains. Fibers were prepared by spinning more concentrated solutions into a butanone coagulation bath. Conductivity measurements were then made on the drawn films and fibers, and tensile test measurements performed to determine the peak stress and modulus of the drawn films and fibers. The reaction conditions under which the different polyanilines were synthesized, and their molecular weight, were found to have a definite effect upon both the electrical and mechanical properties of the drawn films and fibers. The drawn films and fibers can be used as mechanical actuators.
Formation of DNA adducts of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in male Fischer-344 rats.

Abstract 2-Amino-1-methyl-6-phenylimidazo[4,5- b ]pyridine (PhIP) is known to induce colon tumors in male Fischer-344 rats. Using 32 P-postlabeling assays, we have examined PhiP-DNA adduct formation in various organs and white blood cells (WBCs) of the male Fischer-344 rat 24 h after a single oral dose of 0, 0.5, 5 or 50 mg PhIP/kg. Three PhIP-DNA adducts were detected in WBCs and in all organs, except in the liver and stomach which had only two adducts. The extent of adduct formation was dose-related, but at 0.5 mg/kg no adducts could be detected in any of the organs. At 50 mg/kg, adduct levels, expressed as relative adduct labeling values (RAL × 10 7 , or adducts per 10 7 nucleotides assuming complete labeling) were highest in the large intestine (5.66), followed by WBCs (5.04), stomach (1.44), small intestine (1.32), kidney (1.16), liver (0.67) and lungs (0.52). It is concluded that orally administered PhIP forms high levels of specific DNA adducts in the large intestine, the target organ in PhIP carcinogenesis in the male Fischer-344 rat, and that the high level of adducts in WBCs indicates that significant amounts of the ultimate carcinogenic form of PhIP are present in the circulation.
U. Vē. Cāminātaiyar and the Construction of Tamil Literary “Tradition”

U. Vē. Cāminātaiyar (1885–1942) is arguably one of the most influential figures of the so-called “Tamil Renaissance” of the nineteenth and early twentieth centuries; his work has profoundly shaped the study of Tamil literature, both in India and the Euro-American academy, for more than a century. Among his many literary works is a long and incomplete autobiographical treatise known as Eṉ Carittiram, literally “My Life Story,” initially published in 122 installments between 1940 and 1942. What little scholarly attention this fascinating autobiographical narrative has received thus far has largely read the text as an artless, transparent documenting of South Indian literary culture in the late nineteenth century. Yet the text reveals substantial rhetorical art on close reading. Greater attention to Cāminātaiyar’s specific context and probable concerns when composing (and publicly publishing) Eṉ Carittiram suggests alternative ways of reading Tamil literary history and those texts that he first made widely available.
Preservation of rust fungi in liquid nitrogen

Abstract Spores of rust fungi can be expected to retain viability without loss of infectivity for at least several years when stored in liquid nitrogen (−196 °C). Addition of liquid suspending media is harmful and not necessary. Some rust fungi experience cold-induced dormancy when exposed to less than 0 °C for a minute or longer but germinability is dependably restored on applying a heat shock by heating the spores to 40 °C for at least 15 sec during or after thawing. Most rust fungi are not sensitive to moisture content at the time of freezing but Puccinia striiformis must be vacuum dried before freezimg. The need for heat shock may not show up until several days after thawing. All of the rust strains tested to date have retained their properties to the extent tested and for the duration of storage. Data are available for up to 11 years. Preliminary experiments to preserve saprophytic mycelial cultures of P. graminis have so far failed, with and without use of 10% glycerol and 5% DMSO. The successful preservation of rust spores has made feasible the development of a collection of living rust fungi at ATCC beginning in 1965 and which now has over 80 strains in 20 species in 7 genera.
Activation, transformation, and subunit structure of steroid hormone receptors.

I. Introduction Steroid hormones act on a wide variety of target cells to alter their structure and function in remarkably diverse ways. However, much evidence has accumulated to suggest that the different steroid hormones, and even the sterol 1,25-dihydroxyvitamin D, act via similar pathways to produce the same general effects, i.e. the induction of RNA and protein synthesis. These effects are mediated by specific, high affinity hormone-binding proteins termed “receptors.” Steroid receptors have been described in many different target tissues, and they often seem to display as many differences as similarities in both their native structure and their various in vitro physicochemical transformations. Yet the homologies of structure of the different steroid hormones, and the similarities in their effector pathways and general metabolic effects, suggest that there may be certain broad similarities about these receptors. It is the purpose of this review to compare the findings on various steroid receptors and...
Dacryodes edilsonii, a new species from southwestern Amazonia. Studies in neotropical Burseraceae XII

Dacryodes edilsonii Daly (Burseraceae) is one of at least 14 still undescribed neotropical species in the genus; it is also one of a large number of new species emerging from intensified botanical exploration of the Brazilian state of Acre in southwestern Amazonia. The new species is easily distinguished from most other Neotropical species of the genus by its usually densely long-pubescent petiole, rachis, petiolules, and abaxial midvein.
ANISOTROPIC PROPERTIES OF SINGLE-CRYSTALLINE CeNiGe2

The anisotropic properties of CeNiGe2 with a layered crystal structure have been studied by measurements of electrical resistivity, magnetic susceptibility and magnetization. It is confirmed that CeNiGe2 undergoes two-step antiferromagnetic transition at TNI = 4 K and TNII = 3 K as reported earlier on polycrystalline samples. CeNiGe2 is found to exhibit highly anisotropic properties with an easy magnetization axis along the longest crystallographic b direction. The magnetization ratio M(H//b)/M(H⊥b) is estimated to be about 15 at 5 T. The in-plane resistivity ρ⊥b(T) shows double maxima typical of that expected when an interplay of crystal-field and Kondo effects plays a role. The low-T maximum at 4-K in ρ⊥b(T) is strongly suppressed with increasing magnetic field. This negative magnetoresistance is a result of the strong reduction of magnetic scattering by the ferromagnetic alignment of Ce magnetic moments.
Hemin enhances differentiation and maturation of cultured regenerated skeletal myotubes

Satellite cells, isolated from marcaine-damaged rat skeletal muscle, differentiate in culture to form contracting, cross-striated myotubes. Addition of 20 microM hemin (ferriprotoporphyrin IX chloride) to the culture medium resulted in increases in the number, size, and alignment of myotubes; in the number of myotubes that exhibited cross-striations; and in the strength and frequency of myotube contractions. Hemin increased satellite cell fusion by 27%, but decreased cell proliferative rate by 30%. Hemin increased the specific activity of creatine kinase (CK), a sensitive indicator of muscle differentiation, by 157%. Separation of CK isoenzymes by agarose gel electrophoresis showed that hemin increased only the muscle-specific CK isoenzymes (MM-CK and MB-CK). Thus, hemin seems to duplicate some of the effects of innervation on cultured myotubes by increasing contraction frequency and strength, appearance of cross-striations, and muscle-specific isoenzymes. In contrast, 3-amino-1,2,4-triazole, an inhibitor of heme biosynthesis, decreased the number of cross-striated myotubes, the strength and frequency of myotube contractions, and CK activity. These inhibitory effects were reversed by hemin. Collectively, these results demonstrate a physiologically significant role for heme in myotube maturation.
Effect of two dietary concentrate levels on tenderness, calpain and calpastatin activities, and carcass merit in Waguli and Brahman steers

The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values, and low calpastatin activity, all of which are related to more tender meat.
An electron-capture gas chromatographic method for the determination of piperidine content in brain tissue.

Abstract A specific and sensitive electron-capture gas-liquid chromatographic method was devised for the estimation of piperidine, a putative neurotransmitter, in rat and dog brain tissue. The procedure involves the addition of an internal standard, 2-ethylpiperidine, to brain homogenates followed by extraction of the amines into benzene at an alkaline pH. The amines are back-extracted into acid and subsequently reextracted into benzene under alkaline conditions. The isolated amines are converted to the trichloroacetyl derivatives prior to chromatographic analysis. The sensitivity of the method is such that 3 ng of piperidine (35 pmol) per aliquot of brain homogenate can be analyzed. Combined gas-liquid chromatography/mass spectrometry confirmed the specificity of analysis. No significant difference was observed in the regional brain distribution of piperidine in the rat (∼30 ng/gm) or the dog (∼20 ng/gm).
Sidewall Surface Roughness of Sputtered Silicon I: Surface Modelling

AbstractMathematical models for the calculation of sidewall surface roughness have been developed for focused ion beam (FIB) sputtering. The surface roughness profile at the sidewall was different to the bottom surface profile for the same sputtering parameters and substrate material. The cumulative sputtering by the Gaussian beam creates a steady state surface profile at the sidewall which has been used to develop surface roughness models. The ion intensity distribution profile was considered to be Gaussian. The beam function includes ion type, ion acceleration voltage, beam radius, tailing and neighbouring of the successive beams. Knowing the beam radius and pixel spacing, sidewall surface roughness of FIB sputtered microfeatures can be calculated using these models. The substrate material function has no direct effect on the sidewall surface profile if the same material is used for the study of beam profile and fabrication of microfeatures.
LOCATING THE CIVIL SPHERE

Jeff Alexander (2006) has too many productive years ahead for The Civil Sphere to be called a culminating text, but it is a tome (793 pages) that refines basic threads of roughly three decades of p...
Mechanism of release and fate of excised oligonucleotides during nucleotide excision repair

A wide range of environmental and carcinogenic agents form bulky lesions on DNA that are removed from the human genome in the form of short, ∼30-nucleotide oligonucleotides by the process of nucleotide excision repair. Although significant insights have been made regarding the mechanisms of damage recognition, dual incisions, and repair resynthesis during nucleotide excision repair, the fate of the dual incision/excision product is unknown. Using excision assays with both mammalian cell-free extract and purified proteins, we unexpectedly discovered that lesion-containing oligonucleotides are released from duplex DNA in complex with the general transcription and repair factor, Transcription Factor IIH (TFIIH). Release of excision products from TFIIH requires ATP but not ATP hydrolysis, and release occurs slowly, with a t½ of 3.3 h. Excised oligonucleotides released from TFIIH then become bound by the single-stranded binding protein Replication Protein A or are targeted by cellular nucleases. These results provide a mechanism for release and an understanding of the initial fate of excised oligonucleotides during nucleotide excision repair. Background: The fate of oligonucleotides released during nucleotide excision repair is unknown. Results: Damage-containing oligonucleotides are released from duplex DNA in complex with TFIIH but then slowly dissociate and bind RPA or are degraded by nucleases. Conclusion: Excised oligonucleotides form complexes with TFIIH and RPA during excision repair. Significance: Oligonucleotides released during nucleotide excision repair may function in the cellular response to DNA damage.
Evidence for reutilization of surface receptors for α-macroglobulin · protease complexes in rabbit alveolar macrophages

Abstract Rabbit alveolar macrophages internalize α-macroglobulin 125 I-trypsin complexes subsequent to binding of complexes to high affinity surface receptors. Cells were capable of accumulating a 5–10 fold greater amount of αM · 125 I-T at 37°C than at 0°C. At 0°C cell-bound αM · 125 I-T was bound solely to surface receptors, whereas at 37°C the majority (85%) of cell-bound radioactivity was intracellular. The temperature-dependent accumulation of αM · 125 I-T did not reflect a change in surface receptor number or ligand-receptor affinity. Rather, the greater rate of uptake reflected continued internalization of αM · 125 I-T complexes. At 37°C cells took up 5–9 fmole αMT per μg cell protein per hr, whereas binding to surface receptors accounted for 0.5–0.7 fmole per μg cell protein. Once bound to surface receptors internalized αM · 125 I-T was localized in lysosomes, where it was degraded at a rate of 35–45% per hr. Following binding of αM · T to receptors at 37°C, but not at 0°C, unoccupied receptors could be found on the cell surface. Using cycloheximide to probe receptor turnover, I calculated that receptors were replenished at a rate of 15% per hr. Cells incubated in the presence of cycloheximide exhibited unaltered ligand uptake and catabolism for hours. Thus the reappearance of receptor activity during ligand uptake was not primarily due to de novo receptor synthesis. The rate of ligand uptake was a function of the number of surface receptors. Measurement of αM 125 I-T binding to subcellular fractions did not reveal the presence of any intracellular reservoir of receptors. These observations are consistent with the hypothesis that continued ligand uptake reflects receptor reutilization.
Acyl Carrier Protein-specific 4′-Phosphopantetheinyl Transferase Activates 10-Formyltetrahydrofolate Dehydrogenase

4′-Phosphopantetheinyl transferases (PPTs) catalyze the transfer of 4′-phosphopantetheine (4-PP) from coenzyme A to a conserved serine residue of their protein substrates. In humans, the number of pathways utilizing the 4-PP post-translational modification is limited and may only require a single broad specificity PPT for all phosphopantetheinylation reactions. Recently, we have shown that one of the enzymes of folate metabolism, 10-formyltetrahydrofolate dehydrogenase (FDH), requires a 4-PP prosthetic group for catalysis. This moiety acts as a swinging arm to couple the activities of the two catalytic domains of FDH and allows the conversion of 10-formyltetrahydrofolate to tetrahydrofolate and CO2. In the current study, we demonstrate that the broad specificity human PPT converts apo-FDH to holoenzyme and thus activates FDH catalysis. Silencing PPT by small interfering RNA in A549 cells prevents FDH modification, indicating the lack of alternative enzymes capable of accomplishing this transferase reaction. Interestingly, PPT-silenced cells demonstrate significantly reduced proliferation and undergo strong G1 arrest, suggesting that the enzymatic function of PPT is essential and nonredundant. Our study identifies human PPT as the FDH-modifying enzyme and supports the hypothesis that mammals utilize a single enzyme for all phosphopantetheinylation reactions.
Evaluating the Long-Term Durability of Externally Bonded FRP via Field Assessments

AbstractFiber-reinforced polymer composites (FRP) are an attractive repair option for reinforced concrete structures, but whereas laboratory durability tests have indicated that FRP generally performs well in many environments, their long-term performance in field environments is not well understood. This case study describes an effort to collect in situ data about the FRP used to repair a concrete arch bridge 8 years after the FRP was originally placed. On-site assessment efforts included inspection for voids between the concrete and FRP using acoustic sounding and thermographic imaging and pull-off tests to check the bond strength. Large debonded regions of FRP were also cut from the structure and tested in tension in the laboratory. Results generally pointed to some level deterioration. Many new voids were found, existing voids had grown, pull-off testing showed weaker bond strengths, and the tensile strengths were quite low compared to design values. However, a lack of initial data make it difficult t...
Inhibition of Phospholipase C-γ1 Activation Blocks Glioma Cell Motility and Invasion of Fetal Rat Brain Aggregates

OBJECTIVE Phospholipase C (PLC)-gamma is a cytosolic enzyme activated by several growth factor (GF) receptors (epidermal GF receptor [EGFR], platelet-derived GF receptor, and insulin-like GF 1 receptor), and its activation is associated with increased cell motility (but not cell proliferation) in nonglioma cell lines. Because up-regulated activation of EGFR has been consistently linked to poor patient survival in patients with glioblastoma multiforme (GBM) and because inhibition of EGFR activation by tyrosine kinase inhibitors prevents glioma infiltration in vitro, we hypothesized that inhibition of PLC-gamma activation would inhibit glioma cell invasiveness. METHODS Our experimental model assesses tumor spheroid invasion of fetal rat brain spheroids by confocal microscopy. We treated U87 GBM spheroids, and those derived from a single patient, with the PLC inhibitor U73122. We also transfected rat C6 glioma cells with the PLCz complementary deoxyribonucleic acid coding for a dominant negative PLC-gamma1 src-homology-2/src-homology-3 peptide fragment, which blocks binding and activation of PLC-gamma1 by GF receptors. Two clones (C6F and C6E) were grown into spheroids and were tested for invasiveness in the spheroid model and for responsiveness to GFs in a standard in vitro motility assay. RESULTS The infiltration rate of the patient GBM cell line overexpressing wild-type EGFR was reduced by 2 micromol/L U73122 from a slope (percent invasion/h) of 0.74+/-0.08 (with the inactive congener U73343) to 0.04+/-0.053 (P = 8 x 10(-7) by two-tailed t test, 92% reduction); the integral rate, another measure of invasion, was reduced from 49.7+/-13 percent-hours per hour to 13.6+/-12 (P = 0.002, 72% reduction). The U87 spheroid invasion rate was reduced by 0.5 micromol/L U73122 from 46.7+/-8.5 percent-hours per hour to 11.2+/-4.6 (P = 3 x 10(-5)); the slope decreased from 1.7+/-0.41 percent per hour to 0.35+/-0.14 (P = 0.0001). The C6F and C6E clones demonstrated attachment to and "surrounding" of the fetal rat brain aggregate but no true invasion by confocal or light microscopy. PLCz blocked the motility response to epidermal GF, platelet-derived GF, and insulin-like GF. There was a significant decrease in PLC-gamma1-associated tyrosine phosphorylation. CONCLUSION These results support a key role for PLC-gamma activation as a common postreceptor pathway for GF-induced tumor infiltration and further identify PLC-gamma1 as a possible target for anti-invasive therapy for GBMs.