cssi/SciSciGPT-SciSciNet huggingface dataset:
PCB concentrations in stream sunfish (Lepomis Auritus and L. Macrocmirus) in relation to proximity to chronic point sources

Sunfish (Lepomis auritus and L. macrochirus) were used to monitor polychlorinated biphenyl (PCB) contamination in a group of small streams flowing into a larger stream/reservoir system. Mean PCB concentrations in sunfish appeared to reflect exposure conditions at the site of capture. Fish from uncontaminated sites 1 to 2 km distant from PCB-contaminated sites did not exhibit PCB contamination, and PCB concentrations in fish downstream from a discrete source decreased at a rate greater than or equal to downstream dilution of the point source. Mean PCB concentrations in fish near the source exhibited relatively large (-40%) fluctuations between semi-annual sampling periods, suggesting that PCB concentrations in sunfish populations may respond rapidly to changes in exposure. Sunfish were not sensitive enough indicators of contamination to use in assessing whether or not problematic levels of contamination may occur in other species. Although the presence of PCB contamination in sunfish can be used to infer that PCBs are elevated in other species, the absence of PCB contamination in sunfish cannot be used to infer that older, fattier fish higher up the food chain are uncontaminated.
Copper-Catalyzed Azide–Alkyne Click Chemistry for Bioconjugation

The copper-catalyzed azide-alkyne cycloaddition reaction is widely used for the connection of molecular entities of all sizes. A protocol is provided here for the process with biomolecules. Ascorbate is used as reducing agent to maintain the required cuprous oxidation state. Since these convenient conditions produce reactive oxygen species, five equivalents of a copper-binding ligand is used with respect to metal. The ligand both accelerates the reaction and serves as a sacrificial reductant, protecting the biomolecules from oxidation. A procedure is also described for testing the efficiency of the reaction under desired conditions for purposes of optimization, before expensive biological reagents are used.
If Only We Spoke the Same Language—We Would Have So Much to Discuss*

Good afternoon. I am Peter Byers, president of The American Society of Human Genetics. Welcome to the 55th Annual Meeting of our Society. I extend a special welcome to those of you who have taken time away from rebuilding your lives, your homes, and your workplaces in New Orleans to join us at this wonderful meeting, even in the face of such adversity.
Net transfer of phosphatidylcholine from plasma low density lipoproteins to sphingomyelin-apolipoprotein A-II complexes by bovine liver and human plasma phospholipid exchange proteins

Bovine liver phosphatidylcholine exchange protein facilitated the net transfer of dipalmitoyl phosphatidyl[N-methyl-14C]cholme from radiolabeled low density lipoproteins (LDL) to complexes of sphingomyelin and apolipoprotein A-II. Transfer of the radiolabeled phosphatidylcholine was dependent on temperature and incubation time, as well as the ratio of LDL to sphingomyelinapolipoprotein A-II. When unlabeled LDL was incubated with sphingomyelinapolipoprotein A-II complex containing [N-methyl-14C]sphingomyelin, negligible amounts of the radiolabel were transferred to the LDL, implying that the transfer of phosphatidylcholine to the sphingomyelin-apolipoprotein A-II complex was not coupled with a return of sphingomyelin to the LDL. Bovine liver phosphatidylcholine exchange protein also facilitated the net transfer of dipalmitoyl phosphatidyl[N-methyl-14C]choline from sonicated vesicles of 1-palmitoyl-2-palmitoleoyl phosphatidylcholine to sphingomyelin-apolipoprotein A-II complex. Dansyl phosphatidylethanolamine incorporated in the donor vesicles was not transferred to the sphingomyelin-apolipoprotein A-II complex, indicating that phospholipid transfer was not due to a disruption of the vesicles and subsequent fusion of vesicle remnants with the sphingomyelin-apolipoprotein A-II complex. Bovine liver phosphatidylcholine exchange protein did not transfer dipalmitoyl phosphatidyl[N-methyl-14C]choline or [3H]cholesteryl esters from high density lipoproteins (HDL) to sonicated vesicles of sphingomyelin. Fluorescence polarization studies showed that relative to the sphingomyelin-apolipoprotein A-II complexes, the sphingomyelin vesicles have a rigid structure which may account for this lack of transfer of the phosphatidyl[14C]choline. Phospholipid exchange protein(s) isolated from human plasma also facilitated the net transfer of dipalmitoyl phosphatidyl[14C]choline from LDL to sphingomyelin-apolipoprotein A-II complexes.
Mean-square stability of delay-differential equations with non-stationary random coefficients

Abstract The mean-square asymptotic stability of the equilibrium stale of a system of linear stochastic delay-differential equations with general non-stationary random coefficients is studied. The Lyapunov method of stability analysis is employed and several criteria for the mean-square stability of the equilibrium state of the system are established. A few examples are solved and the application of the method is discussed.
Delineation of geological facies from poorly differentiated data

The ability to delineate geologic facies and to estimate their properties from sparse data is essential for modeling physical and biochemical processes occurring in the subsurface. If such data are poorly differentiated, this challenging task is complicated further by the absence of a clear distinction between different hydrofacies at locations where data are available. We consider three alternative approaches for analysis of poorly differentiated data: a k-means clustering algorithm, an expectation–maximization algorithm, and a minimum-variance algorithm. Two distinct synthetically generated geological settings are used to analyze the ability of these algorithms to assign accurately the membership of such data in a given geologic facies. On average, the minimum-variance algorithm provides a more robust performance than its two counterparts, and when combined with a nearest neighbor algorithm, it also yields the most accurate reconstruction of the boundaries between the facies.
RNA synthesis in unfertilized sea urchin eggs.

Abstract We have examined the synthesis of messenger-like RNA in unfertilized sea urchin eggs. Most of the RNA synthesized is restricted to the nucleus and sediments from 16 to 30S. A small fraction can be isolated from the postmitochondrial supernatant and displays a sedimentation profile typical of embryonic mRNA with peaks at 9 and 18S. This cytoplasmic RNA is largely present as free RNPs and we estimate that less than 20% of the RNA is in polysomes. The RNA made in the egg is unstable and reaches a steady state with a half-time of about 30 min. We have examined the accumulation of RNA in the egg and have calculated a rate of synthesis of 1.4 × 10 −14 g of RNA/min/egg which is similar, on a per-nucleus basis, to that found in the just-fertilized egg and very early embryo. It is approximately 10 times greater than the rate of RNA synthesis in the blastula nucleus. We estimate that the RNA synthesized by the unfertilized egg amounts to a maximum of 3 × 10 −13 g of potential mRNA at the time of fertilization, or 10–15% of its immediate needs. This RNA cannot account for the increase in protein synthesis that occurs after fertilization, which must be the result of the translation of another population of more stable egg or oogenic mRNA that is kinetically distinct from the RNA we have measured. The steady-state level of labeled RNA present in the egg does not change upon fertilization until after the first cleavage, at about 2.5 hr after fertilization. Thus the RNA synthesis that occurs in the just-fertilized zygote appears to be merely a continuation (at least quantitatively) of the RNA synthesis taking place in the egg.
Influence of Lead Impurity on the Low-Temperature Color-Center Production in KC1

The growth of optical absorption bands in the visible and ultraviolet as a function of 1.5-MeV electron irradiation at liquid-nitrogen temperature has been measured for high-purity and lead-doped KCl. Dissolved lead causes the coloration near 360 nm to be enhanced; the rate of growth increases monotonically with Pb concentration, in agreement with previous studies of trapped holes. The $F$ coloration is also enhanced by small amounts of impurity; however, the $F$-growth enhancement saturates at impurity levels of 20-100 ppm lead. An actual lowering of the $F$-center production rate is observed when samples doped with more than 100 ppm lead are used. This lowering is shown to be due to an increase in the $\ensuremath{\alpha}$-center-to-$F$-center ratio in highly doped KCl. An explanation is proposed for the increased $F$-center coloration in terms of interstitial-$F$-center recombination and interstitial stabilization by the impurities.
Regeneration and the need for simpler model organisms

The problem of regeneration is fundamentally a problem of tissue homeostasis involving the replacement of cells lost to normal 'wear and tear' (cell turnover), and/or injury. This attribute is of particular significance to organisms possessing relatively long lifespans, as maintenance of all body parts and their functional integration is essential for their survival. Because tissue replacement is broadly distributed among multicellular life-forms, and the molecules and mechanisms controlling cellular differentiation are considered ancient evolutionary inventions, it should be possible to gain key molecular insights about regenerative processes through the study of simpler animals. We have chosen to study and develop the freshwater planarian Schmidtea mediterranea as a model system because it is one of the simplest metazoans possessing tissue homeostasis and regeneration, and because it has become relatively easy to molecularly manipulate this organism. The developmental plasticity and longevity of S. mediterranea is in marked contrast to its better-characterized invertebrate cohorts: the fruitfly Drosophila melanogaster and the roundworm Caenorhabditis elegans, both of which have short lifespans and are poor at regenerating tissues. Therefore, planarians present us with new, experimentally accessible contexts in which to study the molecular actions guiding cell fate restriction, differentiation and patterning, each of which is crucial not only for regeneration to occur, but also for the survival and perpetuation of all multicellular organisms.
A tradeoff between space and time: Dimensional constants in mammalian ecology

Abstract Size-independent dimensional constants are proposed as a tool for analysis of life histories and community structure. The number of conspecific individuals occupying the average home-range in the long-run is 2·15 M −0·02 , accomplished sequentially or socially at opposite ends of the mouse to wapiti body size range. Annual biomass turnover per species per hectare is also independent of body size, 0·93 N −0·04 .
The synthesis of the UV-screening pigment, scytonemin, and photosynthetic performance in isolates from closely related natural populations of cyanobacteria (Calothrix sp.).

Summary Two populations of the cyanobacterium Calothrix sp. found in Yellowstone thermal spring outflows differ greatly in their contents of scytonemin, a UV-screen- ing pigment, and in their photosynthetic carbon assimilation rates. Clonal isolates from both popula- tions were used to investigate these phenotypic dif- ferences. Identical partial 16S rDNA sequences ( ~ 900 bp) suggest a very close relationship between the two Calothrix populations and indicate that envi- ronmental differences may, in part, explain the field observations. The effects of native spring water on scytonemin synthesis and photosynthesis were tested during experiments using plated cells. Results show differences in the spring water environment were at least partly responsible for the differences in scytonemin content observed in the field. Further- more, spring water effects on photosynthetic perfor- mance suggest adaptation in these strains to their spring of origin. Controlled experiments performed using cultures grown in artificial liquid medium showed no significant difference in photosynthetic carbon uptake between strains. However, significant differences were detected in their ability to synthesize scytonemin indicating genetic differences between populations. These findings suggest that both genetic and environmental differences are responsible for the naturally occurring variation in scytonemin content and photosynthetic ability in these two closely related populations.
TGFβ signaling at the summit

Ligands belonging to the transforming growth factor (TGF) β superfamily have emerged as major regulators of a wide variety of developmental events, ranging from the earliest steps in germ layer patterning of the pre-gastrula embryo to tissue healing, regeneration and homeostasis in the adult. Recently, Caroline Hill and Bob Lechleider organized the third in a bi-annual series of FASEB meetings on TGFβ signaling and development at Snowmass (CO, USA). This meeting highlighted the ongoing interplay between advances in our understanding of the molecular biology of TGFβ family signaling and in investigations into its roles in specific developmental events.
How Ambiguity Results in Excellence: The Role of Hierarchy and Reputation in U.S. Army Special Forces

This article explores how group reputations get made and unmade within the strictures of an elite military organization. For instance, within teams there are both formal and informal pecking orders. Above teams there exist layers of command and control. "Need to know" and information flows are critical to the construction of A-team identities both among teams and for commanders' consumption. Yet, the view from within teams and of teams is never the same. From within, teams are thought never to be equal. From above they are expected to be interchangeable. As this article describes, hierarchy is actually bolstered by such different perspectives, and teams work better as a result.
RecQ helicase and RecJ nuclease provide complementary functions to resect DNA for homologous recombination

Recombinational DNA repair by the RecF pathway of Escherichia coli requires the coordinated activities of RecA, RecFOR, RecQ, RecJ, and single-strand DNA binding (SSB) proteins. These proteins facilitate formation of homologously paired joint molecules between linear double-stranded (dsDNA) and supercoiled DNA. Repair starts with resection of the broken dsDNA by RecQ, a 3′→5′ helicase, RecJ, a 5′→3′ exonuclease, and SSB protein. The ends of a dsDNA break can be blunt-ended, or they may possess either 5′- or 3′-single-stranded DNA (ssDNA) overhangs of undefined length. Here we show that RecJ nuclease alone can initiate nucleolytic resection of DNA with 5′-ssDNA overhangs, and that RecQ helicase can initiate resection of DNA with blunt-ends or 3′-ssDNA overhangs by DNA unwinding. We establish that in addition to its well-known ssDNA exonuclease activity, RecJ can display dsDNA exonuclease activity, degrading 100–200 nucleotides of the strand terminating with a 5′-ssDNA overhang. The dsDNA product, with a 3′-ssDNA overhang, is an optimal substrate for RecQ, which unwinds this intermediate to reveal the complementary DNA strand with a 5′-end that is degraded iteratively by RecJ. On the other hand, RecJ cannot resect duplex DNA that is either blunt-ended or terminated with 3′-ssDNA; however, such DNA is unwound by RecQ to create ssDNA for RecJ exonuclease. RecJ requires interaction with SSB for exonucleolytic degradation of ssDNA but not dsDNA. Thus, complementary action by RecJ and RecQ permits initiation of recombinational repair from all dsDNA ends: 5′-overhangs, blunt, or 3′-overhangs. Such helicase–nuclease coordination is a common mechanism underlying resection in all organisms.
Maturation of dendritic cells for enhanced activation of anti-HIV-1 CD8(+) T cell immunity.

Maturation of dendritic cells (DC) to enhance their capacity to activate T cell immunity to HIV-1 is a key step in immunotherapy of HIV-1 infection with DC. We compared maturation of DC derived from HIV-1-uninfected subjects and infected subjects on antiretroviral therapy (ART) or ART naive by CD40 ligand (CD40L) and combinations of TLR3 ligand polyinosinic:polycytidylic acid [poly(I:C)] and inflammatory cytokines IFN-gamma, IFN-alpha, IL-1beta, and TNF-alpha. The greatest levels of virus-specific IFN-gamma production by CD8(+) T cells were stimulated by DC treated with CD40L, followed by DC treated with the poly(I:C)-cytokine combination. The highest levels of IL-12p70 were produced by DC treated with CD40L + IFN-gamma, followed by CD40L and the poly(I:C)-cytokine combination. Neutralization of IL-12p70 indicated that it was only partially involved in direct enhancement of antiviral CD8(+) T cell activity. DC stimulation of antiviral CD8(+) T cell reactivity was enhanced by activated CD4(+) T cells at low concentrations but was suppressed at higher CD4(+) T cell concentrations. Maturation of DC with CD40L obviated the need for CD4(+) T cell help and overcame this suppressive activity. Finally, we showed that DC from HIV-1-infected subjects on ART, which were treated with the poly(I:C)-cytokine combination, retained the capacity to produce IL-12p70 and activate anti-HIV-1 CD8(+) T cell responses after restimulation with CD40L, with or without IFN-gamma. Thus, DC from HIV-1-infected subjects can be engineered with CD40L or a poly(I:C)-cytokine combination for enhancing CD8(+) T cell responses to HIV-1, which has potential applications in HIV-1 immunotherapy.
The critically ill neonate with infection: Management considerations in the term and preterm infant

Abstract A brief review of recent occurrence data, as well as management and evaluation issues in newborn infants admitted to intensive care with infection, is presented. The results show that the rate of infections in symptomatic term (3.2%) and very-low-birth-weight infants (2% to 25%) is high. The most frequently cultured microorganism is Staphylococcus epidermidis, especially in the very-low-birth-weight infant. The most frequent laboratory test used in the work-up of suspected infection is the blood culture (aerobic media only), with cerebrospinal fluid and urine cultures obtained in selected patients. Screening blood tests have not been useful in identifying patients who are infected. Prevention strategies should be considered that (1) use breast milk for feeding the immature infant; (2) utilize the American Academy of Pediatrics/American College of Obstetricians and Gynecologists guidelines for prevention of early-onset group B streptococcus infection; and (3) use preservative-free topical ointment on the skin of immature infant. The conclusions show that the future of identifying patients with infection rests with development of accurate, inexpensive, and rapid testing using polymerase chain reaction amplification of bacterial/fungal DNA. Prevention of these infections may lie in the future development and use of monoclonal or polyclonal antibodies against prevalent microorganisms. Copyright © 2000 by W.B. Saunders Company
Picric Acid as A Destaining Agent for Iron Alum Hematoxylin

A saturated aqueous solution of picric acid is used to differentiate paraffin sections and smeared pollen-mother-cells stained in Heidenhain's and Delafield's hematoxylins. The method proceeds as usual, except that the iron alum in the destaining process is replaced by picric acid. Mixtures of picro-sulfuric acid and dilute Delafield's hematoxylin and mixtures of picric acid and aqueous hematoxylin have also been tested, of which the latter yields the better result, but is not as good as the other method described here.
Application of deformable-body mean axis to flexible multibody system dynamics

Abstract While a body-fixed axis is commonly employed as a reference for rigid components, a moving axis is suggested for flexible bodies that undergo large rotations. There are, however, an infinite number of arrangements for the body axes of flexible components. In order to define a unique displacement field, a set of reference conditions that define the nature of the body axis have to be imposed. These reference conditions are mainly dictated by physical considerations. In multibody systems the motion of flexible bodies are constrained by and coupled with the motion of other components in the system through a set of nonlinear constraint equations that describe joints between different bodies. In this paper the problem of selecting an axis for flexible bodies is addressed in the frame of a general finite element development for both planar and spatial multibody systems. A body reference satisfying the mean-axis conditions has been selected for a detailed discussion.
Market mavens′ purchase decision evaluative criteria: implications for brand and store promotion efforts

The market maven is looked to by others for a wide variety of product, price, brand, and shopping information. The market maven scale and questions regarding the importance of various evaluative criteria applied when selecting brands and stores for a variety of consumer products was administered to 306 couples with husbands and wives responding independently. Demographic data suggested that mavens identified were similar to those found in other studies. Although the relationship varied by product and criterion, mavens generally ascribed more importance to evaluative criteria than did nonmavens. Mavenism was found to relate to the importance placed on brand and retail store evaluative criteria differently for men and women. Mavenism among women was associated with greater concern for both brand and store evaluative criteria while mavenism among men was generally associated with a greater emphasis on brand evaluative criteria.
To branch or not to branch that is the question

One of the most contentious areas in software development is branching. Proponents of agile development methodologies are often against the concept of branching as a matter of principle, other large software development projects, such as Windows, are heavy users of branches to control the software generated by thousands of its engineers. Microsoft is migrating its development processes to be able to simultaneously produce software as both stand-alone products and as a SAAS (e.g. Windows 8 and Azure), requiring a re-architecture of these processes. To fully understand the impact of any changes to their development processes the product groups addressed the question of whether and how to use branching within its development process. Bases on this assessment this talk attempts to go back to first principles in regard to software development and shows that there are a lot more similarities than differences between agile and non-agile software development methods. The talk will also discuss the pros and cons of branching identifying where it will positively and negatively impact software development.
One-equivalent oxidative charge storage on an [Mn2O2]3+ core: Synthesis, crystal structure and resonance Raman spectra of [Mn2O2(pbz)4]n+ (n = 3, 4)

Abstract Complexes similar in structure but with a higher oxidation state of the metal center mimic charge-storage processes observed in biological systems. An oxomanganese system based on the ligand 2(2′-pyridyl)benzimidazole, [Mn2O2(pbz)4]3+, which contains the biologically relevant mixed-valent di-μ-oxo Mn(III,IV) unit capable of undergoing a pH controlled one-electron redox conversion to the Mn(IV,IV) state, is described. The [Mn2O2(pbz)4]4+ and [Mn2O2(pbz)4]3+ complexes have both been isolated and structurally characterized by X-ray crystallography and UV-Vis, EPR and resonance Raman spectroscopic methods. A characteristic Mn(IV)-O stretching mode of the (di-μ-oxo)dimanganese core in these complexes at ∼695 cm−1 provides a useful reference probe for structural characterization of Mn containing active sites involving two oxo bridges.
Charting a new course from blackboard to sakai

Ithaca College is charting a new course in the sea of learning management systems leaving the turbulent Blackboard waters to find a safe port of harbor with Sakai. This paper will chronicle the issues that led us to begin charting this course, the initial departmental recommendation, how we involved faculty in the review and decision making process, the technical review process, the pilot and the implementation.Learning management systems are foundational instructional technologies. Yet, the options are limited and not extremely competitive. For the past decade Ithaca College had flip-flopped between Blackboard and WebCT (not necessarily by choice) trying the patience of all involved especially faculty and IT support staff. After the last upgrade forced by the purchase of WebCT by Blackboard, and in light of significant licensing increases, IT administration looked for a way to get out of the turbulent waters and into calmer seas. As a result of a collaborative review and evaluation process, Ithaca College is implementing Sakai hosted by Longsight beginning May 2011 with campus-wide implementation planned for the Fall 2011. This decision and move is significant because it will be the first major enterprise application system that is open source and hosted by an off campus vendor. The decision made sense philosophically, pedagogically and financially. We believe this change will provide a more stable, robust, collaborative environment for the future and will share our process in this paper.
Chip Formation in High-Speed Cutting of Copper and Aluminum

This paper presents metal-cutting data for the high-speed machining of copper and aluminum, each at two levels of purity, and over a range of workpiece temperatures from −326 deg F (80 deg K) to 550 deg F (560 deg K). It has been found that cutting behavior is influenced by purity of work material, its initial temperature, and extent of tool-chip contact. The influence of plastic deformation on chip hardness has been found to be intimately associated with the purity of the work material.
Abstract 3797: Hyperphosphorylation and desumoylation of RanGAP1·SUMO1

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Previous work from our laboratory showed that tumor cells exposed to an anticancer mitotic inhibitor, regosertib (ON 01910.Na), resulted in G2/M arrest and hyperphosphorylation of RanGAP1·SUMO1 (HRGS). These findings suggest that regosertib may act either as an inhibitor of a RanGAP1·SUMO1 phosphatase or stimulant of a new kinase (Cancer Res 2011; 71; 4968-76). We further studied the relationship between dephosphorylation and deSUMOylation of HRGS. In the present study we used DU145 prostate cancer cell line. After exposure to one microM regosertib for 24 h, cells were collected and subjected, in equal portions, to lysis in different lysis buffers composed of basic lysis buffer and varied in supplemented inhibitors. Basic lysis buffer contained 10 mM Tris-HCl, pH 8.0; 150 mM NaCl; 1% Triton; 0.5% NP-40; 1 mM EGTA and 1 mM EDTA. Thus, prepared cell lysates were analyzed by Western blot for expression of phosphorylated and non-phosphorylated forms of RanGAP1, RanGAP1·SUMO1, PP1 and Cdc25C. Results: Roche protease inhibitor cocktail, PMSF (0.5 mM), NaF (1 mM) and Na3VO4 (1mM) as inhibitors added to the basic lysis buffer were unable to protect against loss of SUMO-group from RanGAP1·SUMO1 and, concomitantly, against de-phosphorylation of PP1 phosphatase at T-320. However, addition of N-ethylmaleimide (NEM, an inhibitor of deSUMOylation) as a single inhibitor supplement in the basic lysis buffer resulted in concentration-dependent (2.5 ∼ 40mM) inhibition of deSUMOylation of HRGS. Yet, even at lower NEM concentration RanGAP1, devoid of the SUMO-group, was still phosphorylated. This might be in correlation with our finding that even low concentration of NEM in the lysis buffer kept PP1 in phosphorylated state at T320 (which is inhibitory to PP1), preventing it from auto-dephosphorylation and re-activation. Also, neither regosertib (up to 100 microM) nor okadaic acid (OA, up to 1 microM), added to the basic lysis buffer as putative inhibitors, could prevent loss of SUMO group from HRGS and dephosphorylation of PP1 at T320. Regosertib in the lysis buffer did not prevent dephosphorylation of hyperphosphorylated Cdc25C (aka mitotic Cdc25C), while NEM and OA did (the latter implies that dephosphorylation was carried out by PP1 in the lysate). Conclusion: These data show that hyperphosphorylated RanGAP1·SUMO1 can be deSUMOylated, but remains phosphorylated. DeSUMOylation may be a prerequisite for RanGAP dephosphosphorylation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3797. doi:1538-7445.AM2012-3797
Scanning Tunneling Spectroscopic Studies of the Low-Energy Quasiparticle Excitations in Cuprate Superconductors

We report scanning tunneling spectroscopic (STS) studies of the low-energy quasiparticle excitations of cuprate superconductors as a function of magnetic field and doping level. Our studies suggest that the origin of the pseudogap (PG) is associated with competing orders (COs), and that the occurrence (absence) of PG above the superconducting (SC) transition T_c is associated with a CO energy Δ_(CO) larger (smaller) than the SC gap Δ_(SC). Moreover, the spatial homogeneity of Δ_(SC) and Δ_(CO) depends on the type of disorder in different cuprates: For optimally and under-doped YBa_2Cu_3O_(7−δ) (Y-123), we find that Δ_(SC) < Δ_(CO) and that both Δ_(SC) and Δ(CO) exhibit long-range spatial homogeneity, in contrast to the highly inhomogeneous STS in Bi_2Sr_2CaCu_2O_(8+x) (Bi-2212). We attribute this contrast to the stoichiometric cations and ordered apical oxygen in Y-123, which differs from the non-stoichiometric Bi-to-Sr ratio in Bi-2212 with disordered Sr and apical oxygen in the SrO planes. For Ca-doped Y-123, the substitution of Y by Ca contributes to excess holes and disorder in the CuO_2 planes, giving rise to increasing inhomogeneity, decreasing Δ_(SC) and Δ_(CO), and a suppressed vortex-solid phase. For electron-type cuprate Sr_(0.9)La_(0.1)CuO_2 (La-112), the homogeneous Δ_(SC) and Δ_(CO) distributions may be attributed to stoichiometric cations and the absence of apical oxygen, with Δ_(CO) < Δ_(SC) revealed only inside the vortex cores. Finally, the vortex-core radius (ξ_(halo)) in electron-type cuprates is comparable to the SC coherence length ξ_(SC), whereas ξ_(halo) ∼ 10ξ_(SC) in hole-type cuprates, suggesting that ξ_(halo) may be correlated with the CO strength. The vortex-state irreversibility line in the magnetic field versus temperature phase diagram also reveals doping dependence, indicating the relevance of competing orders to vortex pinning.
Thermodynamic Analysis of “Inter-Turbine” and “Intra-Turbine” Reheat for Marine Gas Turbines

This paper presents thermodynamic analyses of two types of reheat combustion cycles in gas turbines and provides an evaluation of their usefulness in marine power and propulsion applications. Specifically, baseline cycles, using components of various technology levels, were compared to cycles with single-stage reheat (inter-turbine reheat), and continuous or constant temperature reheat (intra-turbine reheat). the results of this primary flow path analysis show that reheat can greatly increase the power density, while reducing the total fuel consumption over a standard warship mission profile. These trends are strongest at lower technology levels, but are also present at higher component technology levels.Copyright © 2004 by ASME
IRON AVAILABILITY FROM WHEAT GLUTEN, SOY ISOLATE, AND CASEIN COMPLEXES

Release of iron bound to animal and vegetable protein sources was investigated. Ferrous and ferric iron complexes with wheat gluten, soy protein isolate, and casein were prepared under conditions shown to bind large quantities of iron to the insoluble residue. These mixtures were lyophilized and ground to a file powder. Treatment of the lyophilized protein-iron-mixtures with 0.1N HCl released 30-68% of the bound iron. Digestion in an HCl-pepsin or an HCl-pepsin-pancreatin system released 64-94% and 85-97% of the bound iron, respectively, indicating that protein-bound iron should be readily freed for absorption within the gastrointestinal tract. Using the hemoglobin repletion technique, protein-bound ferrous iron was statistically as biologically available as the standard, ferrous sulfate. Estimates of the relative biological values for the protein-ferric mixtures were somewhat lower than reported in the literature for ferric pyrophosphate, the free salt used in binding.
The pleasures, perils, and possibilities of undertaking international business research

Brian Toyne, Zaida L. Martinez, & Richard A. Menger (Eds.). 2001. International Business Scholarship: Mastering Intellectual, Institutional, and Research Challenges. Westport, CT: Quorum Books. ISBN: 1-56720-351-5. Masaaki (Mike) Kotabe & Preet S. Aulakh (Eds.). 2002. Emerging Issues in International Business Research. Northampton, MA: Edward Elgar. ISBN: 1-84064-836-8.
Status of the Columbia parallel processors

Abstract We first review the programs currently running on the 16 and 64 node parallel processors at Columbia University. We also mention the future programs planned for these two machines. We devote most of this article to discussing the 256 node machine, giving a very quick overview of the hardware design, the hardware debugging procedure, and the software tools used for writing programs. We conclude by stating the performance of a completed 256 node program.
TARA Trade: a marketing challenge in Lebanon

Subject area Family Business, Entrepreneurship, International Business and Marketing. Study level/applicability This case is intended for an undergraduate business student audience in courses dealing with Entrepreneurship, Family Business, International Business and Marketing. Case overview TARA Trade, a Lebanese souvenir-item designer and distributor owned by two brothers, was facing hostile competition. The partners who operated the business from two different continents had to deal with multiple threats to maintain their market position in a region of the world riddled with political unrest, regulatory chaos and idiosyncratic (distinctive) socio-cultural business practices. Expected learning outcomes Students are challenged to identify solutions to the marketing concerns and analyse the partnership issues faced by the international ownership/management of the business. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or e-mail: support@emeraldinsight.com to request teaching notes.
The dynamic effects of general purpose technologies on Schumpeterian growth

General purpose technologies (GPTs) are drastic innovations characterized by pervasiveness in use and innovational complementarities. The dynamic effects of a GPT are analyzed within a quality-ladders model of scale-invariant Schumpeterian growth. The diffusion path of a GPT across a continuum of industries is governed by S-curve dynamics. The model generates a unique, saddle-path long-run equilibrium. Along the transition path, the measure of industries that adopt the new GPT increases, consumption per capita falls, and the interest rate rises. The growth rate of the stock market depends negatively on the rate of GPT diffusion and the magnitude of the GPT-ridden RD and positively on the rate of population growth. It also follows a U-shaped path during the diffusion process of the new GPT. Finally, the model generates transitional growth cycles of per capita GNP.
A knowledge-based system for tactical situation assessment

To perform tactical situation assessment effectively, a system must be capable of performing tactical information integration, interpretation, and threat evaluation. This paper describes a prototype system for naval surface warfare which incorporates a human operator for integration, an artificial intelligence-based subsystem for interpretation, and an operations research-based system for evaluation. The system provides the operator with an interactive environment for displaying and managing tactical information and tools for interpreting and evaluating it.
Copper(I)/Dioxygen Reactivity with Dinuclear Compounds: Catalytic Oxygenation and Oxo-Transfer to a Ketone.

Dinucleating ligand LH2, with tridentate donors built into a bis(2-pyridyl)methane moiety, is catalytically converted to the bis(2-pyridyl)ketone LO using Cu(I) or Cu(II) ion and dioxygen. The gem-diolate bridged complex [(L(O-)2)CuII2(OClO3-)]+ (4) is generated by reaction of dicopper(I) complex [(LO)CuI2(CH3CN)2]2+ (3) with O2, NO(g), or PhIO, implicating oxo−dicopper(II) intermediates in the ketone oxygenation reactions.
SU‐FF‐T‐320: Observation of Dose Enhancement Between Two Gold Foils with 25MV Photon Beam

Purpose: To study the effect of backscatteredelectrons in enhancing absorbed dose using gold foils. Methods and materials: Tissue equivalent solid phantom and two gold foils with 0.034 mm thickness were used. The first gold foil was placed at 4.5 cm depth and EDR2 film was placed at 6 mm downstream position relative to the gold foil. The second foil was placed at 5.4 mm downstream position relative to the EDR2 film. We used a 25 MV photon beam and 10 × 10 cm2field size. The phantom was set at 100 cm SSD. 200MU was delivered. After the second gold foil was removed, another film was irradiated with the same photon beam, field size, and SSD. Films were analyzed with RIT 113 version 4 (RIT Inc. Colorado Springs, Co). Microsoft Office Excel was also used to analyze the data. Results and discussion: We found that removing the second foil caused a 6% reduction of the dose at the film location. Because the pair production dominates at this energy and with high Z material (gold foil), it is possible that the enhancement was due to the pair production. Pair production generates more electrons and positrons, thereby, increasing backscatteredelectrons as well as annihilation photons. Conclusions: This study showed that there is dose enhancement between two gold foils. The result suggests the possibility of local dose enhancement by using goldnanoparticles.
Traumatic dislocation of testes.

Abstract Traumatic dislocation of the testicle is characterized by an ectopically displaced testis as the result of closed injury. We report on 1 patient with subcutaneous inguinal dislocation of the testis that was successfully treated by immediate dosed reduction. Forty-nine other cases (36 unilateral and 13 bilateral) have been previously cited. Diagnostic guidelines, our therapeutic approach and the relevant literature are presented.
Oxidative Repair of a Thymine Dimer in DNA from a Distance by a Covalently Linked Organic Intercalator

A thymine cyclobutane dimer, site-specifically incorporated in a DNA duplex, is shown to be repaired upon photoexcitation (at 380 nm) of a naphthalene diimide intercalator (NDI), either bound noncovalently to the duplex or covalently appended to the C4 amine of a methylated cytosine base well separated from the thymine dimer. The repair of the thymine dimer is triggered by photooxidation either directly or by DNA-mediated charge transport over a distance of ∼22 A, the separation between NDI and the cyclobutane ring. Photooxidative repair with covalently and noncovalently bound NDI is demonstrated using HPLC under denaturing conditions, where the loss of the thymine dimer-containing strand and the formation of the repaired strand are monitored directly, as well as using a novel gel electrophoretic assay. In this assay, two strands of oligonucleotides containing 5‘- and 3‘-terminal thymidines are first ligated photochemically to yield thymine dimers, and repair is then assayed by monitoring the reversal of the photoligation by intercalators bound either noncovalently or at a distance. Although both NDI and a rhodium intercalator were seen to reverse the photoligation, several anthraquinones and ethidium were unable to promote repair upon irradiation at 350 nm. This photoligation reversal assay provides a rapid screen for thymine dimer repair. The oxidative repair of thymine dimers in a DNA duplex from a distance appears now to be a general phenomenon and requires consideration in developing mechanisms for DNA-mediated charge transport.
Cell growth and tRNA4lys synthesis in mouse 3T3 cells

Abstract The RPC-5 chromatographic profiles of lys-tRNA were analyzed during the growth of 3T3 cells in culture. An inverse relationship was seen between tRNA2lys and tRNA4lys which was markedly influenced by medium changes. This interchange of tRNA2lys and tRNA4lys could be controlled by altering the levels of serum in the medium, or more precisely by altering the serum to cell ratio. A different change in lys-tRNA distribution was seen when the cells reached confluency. The amounts of tRNA2lys, tRNA3lys and tRNA4lys all decreased with a corresponding increase in either tRNA5lys or tRNA6lys. An identical change in lys-tRNA could be produced by shifting sparse cells into a medium containing 10% calf plasma instead of 10% serum. Both tRNAlys profiles and cell growth were returned to normal when the cells were returned to medium with 10% fetal calf serum (FCS) or 10% calf plasma and fibroblast growth factor (FGF). A third alteration in tRNAlys profiles was seen by the addition of cAMP to the cultures. A decrease in tRNA5lys and a corresponding increase in tRNA6lys was seen upon the addition of 10−3 M db-cAMP and was accentuated by the simultaneous addition of 10−3 M methyl isobutylxanthine. These data are consistent with an ordered sequence of tRNAlys modification involving tRNA2lys, tRNA3lys, tRNA4lys, tRNA5Blys and tRNA6lys. Several of the factors which control proliferation appear to control the activity of different tRNA-modifying enzymes in this tRNAlys pathway thereby controlling the levels of tRNA4lys, a tRNA previously shown to correlate directly with the proliferative rate of cells.
Observing the positions of spinning binary systems using LISA

We present an analysis of the expected angular and distance uncertainties of spinning binary systems as measured by the space-based gravitational-wave observatory LISA. We focus on two distinct cases: supermassive coalescing black holes at high redshift and nearby binary star systems with roughly constant orbital frequency. We calculate the uncertainties using least-squares parameter estimation of simulated waveforms that are accurate to 4/2 post-Newtonian order. Our results show that the presence of spin can decrease massive black hole distance and positional uncertainties by as much as factors of 10 and 100, respectively. In optimal circumstances, we find that LISA's massive black hole merger resolution can be as low as 10{sup -6} steradians. However, in low-mass binary systems the presence of spin tends to degrade LISA's resolution by anywhere from a factor of 3 to a factor of 100.
Effect of the Platelet-Activating Factor Antagonist BN 50739 and Its Diluents on Mitochondrial Respiration and Membrane Lipids During and Following Cerebral Ischemia

Recent evidence suggests that platelet-activating factor plays a role in ischemia-induced neural injury. The Pulsinelli-Brierley four-vessel occlusion model was used to study the effect of a synthetic platelet-activating factor antagonist, BN 50739, and its solvents, either dimethyl sulfoxide or hydroxypropyl-beta-cyclodextrin, on cerebral ischemia-reperfusion. Rats were subjected to either 30 min of ischemia or 30 min of ischemia followed by 60 min of recirculation. Changes in the brain mitochondrial free fatty acid pool size, fatty acyl composition of phospholipids, and respiratory function were monitored. When the BN 50739 (2 mg of BN 50739/kg of body weight i.v.) was administered at the onset of recirculation, it significantly reversed the ischemia-induced accumulation of mitochondrial free fatty acids and loss of polyunsaturated fatty acyl chains from phosphatidylcholine and phosphatidylethanolamine while simultaneously improving mitochondrial respiration. Dimethyl sulfoxide alone decreased the mitochondrial level of malonyldialdehyde and total free fatty acid pool size, but there was no improvement in mitochondrial respiration. Hydroxypropyl-beta-cyclodextrin was reported to be pharmacologically inactive and capable of dissolving BN 50739. However, hydroxypropyl-beta-cyclodextrin alone also caused a significant increase in content of cerebral mitochondrial membrane free fatty acids and hydrolysis of phosphatidylcholine in normoxic control animals. The overall effect of BN 50739 on mitochondrial structure and energy metabolism supports the hypothesis that platelet-activating factor may play a key role in ischemia-induced cerebral injury.
Ca2+ transport against its electrochemical gradient in cytochrome oxidase vesicles reconstituted with mitochondrial hydrophobic proteins.

Cytochrome oxidase vesicles have recently been shown to accumulate Ca2+ in an energy-dependent manner. Energization of these vesicles with internally trapped cytochrome c and externally added ascorbate and phenazine methylsulfate generated an internally positive membrane potential and prevented Ca2+ influx (R. N. Rosier and T. E. Gunter, 1980, FEBS Lett.109, 99–103). In contradistinction, when cytochrome oxidase vesicles were reconstituted with complex V, a mitochondrial protein fraction containing the uncoupler binding site (Y. Hatefi, D. L. Stiggall, Y. Galante and W. G. Hanstein, 1974, Biochem. Biophys. Res. Commun.61, 313–321), both Ca2+ uptake and generation of an internally positive membrane potential were observed. The uptake was specifically dependent on energization of electron transport. Control experiments verified that the energization conditions used produced appropriately oriented membrane potentials. Other partially purified hydrophobic mitochondrial protein complexes were found to be less effective than complex V. The reconstituted system showed cation selectivity since Ca2+, Mn2+, and Rb+ were transported, while Na+ was not. Low levels of uncoupler, which did not affect oxidation rates, were found to partially inhibit Ca2+ uptake regardless of the membrane potential polarity. Uncoupling levels of uncoupler markedly inhibited Ca2+ uptake in internally negative cytochrome oxidase vesicles; however, inhibition in internally positive cytochrome oxidase vesicles was less relative to that at lower levels of uncoupler. The uncoupling combination of nigericin, valinomycin, and K+ was inhibitory to uptake regardless of membrane potential polarity. A reconstituted system of oxidative phosphorylation, which contains a hydrophobic protein fraction, energized with cytochrome oxidase similarly accumulated Ca2+ despite formation of an internally positive membrane potential. The results suggest that cytochrome oxidase, when coupled to appropriate hydrophobic mitochondrial proteins, can act as an electrogenic Ca2+ pump deriving its energy directly from electron transport.