1,589 research outputs found
Last days in the old radiation laboratory (ORL), Berkeley, California, 1954
Govindjee, the founding editor of the Historical Corner of Photosynthesis Research, invited me 3Â years ago to tell the story of why I left Melvin Calvinâs laboratory in the mid 1950s long before the 1961 Nobel Prize in Chemistry was awarded to Calvin for the path of carbon in photosynthesis. I have already written my scientific perspective on this topic (see Benson (Photosynth Res 73:29â49, 2002); also see Bassham (Photosynth Res 76:35â52, 2003) as he was also a major player in this research). Here, I present my recollections of my last days in the old radiation laboratory (ORL) at Berkeley, California. References have been added by Govindjee for the benefit of the readers
Visual attention modulates the into ration of goal-relevant evidence and not value
When choosing between options, such as food items presented in plain view, people tend to choose the option they spend longer looking at. The prevailing interpretation is that visual attention increases value. However, in previous studies, âvalueâ was coupled to a behavioural goal, since subjects had to choose the item they preferred. This makes it impossible to discern if visual attention has an effect on value, or, instead, if attention modulates the information most relevant for the goal of the decision-maker. Here, we present the results of two independent studiesâa perceptual and a value-based taskâthat allow us to decouple value from goal-relevant information using specific task-framing. Combining psychophysics with computational modelling, we show that, contrary to the current interpretation, attention does not boost value, but instead it modulates goal-relevant information. This work provides a novel and more general mechanism by which attention interacts with choice
Advanced mineral carbonation: An approach to accelerate CO\u3csub\u3e2\u3c/sub\u3e sequestration using steel production wastes and integrated fluidized bed reactor
© Springer Nature Switzerland AG 2019. Industrial pollution is the major source of global warming through emissions of greenhouse gases (GHGâs) like CO2, CH4, and NO2, causing noticeable increasing in the worldâs temperature. Mineral carbonation is a method of carbon capture and storage (CCS) through which CO2 is sequestered with advantage of permanent sequestration and no need for post-storage surveillance and monitoring through stabilizing the reactive mineral wastes released from metal industries. This paper applied a simple and an inexpensive hydration process as a pre-treatment step for the carbonation of Ladle Furnace (LF) slag, one of the steel production by-products in UAE, followed by direct gas-solid carbonation in a new designed integrated fluidized bed reactor (FBR). About (10â15)% by weight of produced steel, alkaline solid residues were generated, based on the characteristics of the manufacturing process. The integrated FBR was designed to control the flow rate up to 50 l/min with step accuracy of 0.1 l/min, and temperature up to 200 °C through a double jacket electrical heater. Operating pressure can be adjusted up to 6 bars. All parameters are monitored by SCADA system. A mixture gas of 10% CO2, balanced with air, was used to perform the carbonation process and evaluation the carbonation efficiency as well. A gas analyzer installed at the outlet of FBR was used to measure unreacted CO2 gas after leaving the reactor, and calculate the amount of CO2 captured accordingly. Results of analytical techniques like TGA and XRD emphasized the sequestration of CO2 and show a high efficient carbonation process
Structural, DNA/BSA binding interactions and cytotoxicity studies of carboxamide (pyridyl)pyrazine palladium(II) complexes
Reactions of ligands [N2, N3-bis(pyridin-2-yl)pyrazine-2,3-dicarboxamide] (L1), [N2, N3-bis(6-methylpyridin-2- yl)pyrazine-2,3-dicarboxamide] (L2), [N2,N3-bis(4-methylpyridin-2-yl)pyrazine-2,3-dicarboxamide] (L3) and [N2, N3-bis(quinoline-8-yl)pyrazine-2,3-dicarboxamide] (L4) with [PdCl2(NCMe)2] afforded the respective palladium(II) complexes: [Pd2(L1)2Cl2] (Pd1), [Pd2(L2)2Cl2] (Pd2), [Pd2(L3)2Cl2] (Pd3) and [Pd(L4)Cl] (Pd4). Molecular structures of complexes Pd1 and Pd3 are dinuclear containing two bridging bidentate ligand units. The interactions of the palladium complexes (Pd1-Pd4) with calf thymus DNA (CT-DNA) were monitored using UVâVis and fluorescence spectroscopy and revealed intercalative binding modes, with intrinsic binding constants (Kb) in the order of 106 M1. Bovine serum albumin (BSA) interaction was evaluated using fluorescence techniques and displayed a static quenching mechanism. The cytotoxic effects of the complexes Pd1-Pd4 were examined against human breast cancer cell lines MCF-7 and MDA-MB-231, and human transformed lung cell line MRC5-SV2 (a model of lung cancer) and its parental normal lung fibroblast cell line MRC5. While the complexes Pd1 and Pd4 showed significant to moderate cytotoxicity against MCF-7 (IC50 of 11.2 ”M and 61.5 ”M, respectively), complexes Pd2 and Pd3 were inactive. All the complexes were inactive against the MDA-MB-231 cell line, and Pd2-Pd4 were inactive against the MRC5-SV2 cell line. Compounds Pd1 exhibited lower cytotoxicity against the normal cell line MRC5
Phyllosticta citricarpa and sister species of global importance to Citrus.
Several Phyllosticta species are known as pathogens of Citrus spp., and are responsible for various disease symptoms including leaf and fruit spots. One of the most important species is P. citricarpa, which causes a foliar and fruit disease called citrus black spot. The Phyllosticta species occurring on citrus can most effectively be distinguished from P. citricarpa by means of multilocus DNA sequence data. Recent studies also demonstrated P. citricarpa to be heterothallic, and reported successful mating in the laboratory. Since the domestication of citrus, different clones of P. citricarpa have escaped Asia to other continents via trade routes, with obvious disease management consequences. This pathogen profile represents a comprehensive literature review of this pathogen and allied taxa associated with citrus, focusing on identification, distribution, genomics, epidemiology and disease management. This review also considers the knowledge emerging from seven genomes of Phyllosticta spp., demonstrating unknown aspects of these species, including their mating behaviour.TaxonomyPhyllosticta citricarpa (McAlpine) Aa, 1973. Kingdom Fungi, Phylum Ascomycota, Class Dothideomycetes, Order Botryosphaeriales, Family Phyllostictaceae, Genus Phyllosticta, Species citricarpa.Host rangeConfirmed on more than 12 Citrus species, Phyllosticta citricarpa has only been found on plant species in the Rutaceae.Disease symptomsP. citricarpa causes diverse symptoms such as hard spot, virulent spot, false melanose and freckle spot on fruit, and necrotic lesions on leaves and twigs.Useful websitesDOE Joint Genome Institute MycoCosm portals for the Phyllosticta capitalensis (https://genome.jgi.doe.gov/Phycap1), P. citriasiana (https://genome.jgi.doe.gov/Phycit1), P. citribraziliensis (https://genome.jgi.doe.gov/Phcit1), P. citrichinaensis (https://genome.jgi.doe.gov/Phcitr1), P. citricarpa (https://genome.jgi.doe.gov/Phycitr1, https://genome.jgi.doe.gov/Phycpc1), P. paracitricarpa (https://genome.jgi.doe.gov/Phy27169) genomes. All available Phyllosticta genomes on MycoCosm can be viewed at https://genome.jgi.doe.gov/Phyllosticta
The detection of the imprint of filaments on cosmic microwave background lensing
Galaxy redshift surveys, such as 2dF, SDSS, 6df, GAMA and VIPERS, have shown
that the spatial distribution of matter forms a rich web, known as the cosmic
web. The majority of galaxy survey analyses measure the amplitude of galaxy
clustering as a function of scale, ignoring information beyond a small number
of summary statistics. Since the matter density field becomes highly
non-Gaussian as structure evolves under gravity, we expect other statistical
descriptions of the field to provide us with additional information. One way to
study the non-Gaussianity is to study filaments, which evolve non-linearly from
the initial density fluctuations produced in the primordial Universe. In our
study, we report the first detection of CMB (Cosmic Microwave Background)
lensing by filaments and we apply a null test to confirm our detection.
Furthermore, we propose a phenomenological model to interpret the detected
signal and we measure how filaments trace the matter distribution on large
scales through filament bias, which we measure to be around 1.5. Our study
provides a new scope to understand the environmental dependence of galaxy
formation. In the future, the joint analysis of lensing and Sunyaev-Zel'dovich
observations might reveal the properties of `missing baryons', the vast
majority of the gas which resides in the intergalactic medium and has so far
evaded most observations
Discovery of a polyomavirus in European badgers (Meles meles) and the evolution of host range in the family Polyomaviridae.
Polyomaviruses infect a diverse range of mammalian and avian hosts, and are associated with a variety of symptoms. However, it is unknown whether the viruses are found in all mammalian families and the evolutionary history of the polyomaviruses is still unclear. Here, we report the discovery of a novel polyomavirus in the European badger (Meles meles), which to our knowledge represents the first polyomavirus to be characterized in the family Mustelidae, and within a European carnivoran. Although the virus was discovered serendipitously in the supernatant of a cell culture inoculated with badger material, we subsequently confirmed its presence in wild badgers. The European badger polyomavirus was tentatively named Meles meles polyomavirus 1 (MmelPyV1). The genome is 5187 bp long and encodes proteins typical of polyomaviruses. Phylogenetic analyses including all known polyomavirus genomes consistently group MmelPyV1 with California sea lion polyomavirus 1 across all regions of the genome. Further evolutionary analyses revealed phylogenetic discordance amongst polyomavirus genome regions, possibly arising from evolutionary rate heterogeneity, and a complex association between polyomavirus phylogeny and host taxonomic groups
Cytotoxic flavonoids from Lannea egregia Engl. & K. Krause
Background: Lannea egregia Engl. & K. Krause (family: Anacardiaceae) is a well-known medicinal plant in Nigeria whose various parts have been shown to elicit several biological activities. This study specifically explored the leaf of L. egregia for potential cytotoxic compounds. Methods: n-Hexane, dichloromethane and methanolic extracts of the leaf were prepared using the Soxhlet apparatus and concentrated using the rotary evaporator. Compounds were isolated by reversed-phase preparative high-performance liquid chromatography, and the structures were determined by spectroscopic means. The methanolic extract and the isolated compounds were screened for cytotoxicity against HeLa and MCF-7 cancer cell lines, using the MTT assay. Results: Three flavonoids, myricetin (1), myricetin 3-O-α-L-rhamnoside (2) and quercetin 3-O-α-L-rhamnoside (3), were isolated from the methanolic extract of the leaf of L. egregia. The methanolic extract and compound 3 showed the most potent inhibition profiles against the cells, with IC50 values (Mean ± SEM) of 45.3 ± 1.5 ”g/mL and 57.5 ± 0.4 ”g/mL for the methanolic extract, and 36.5 ± 2.0 ”M and 57.9 ± 10.1 ”M for compound 3, against HeLa and MCF-7 cells, respectively. Conclusion: This work shows that L. egregia leaf is moderately cytotoxic, and rich in flavonoids, and the cytotoxicity of the extract is, at least partially, due to the presence of cytotoxic flavonoids. This is the first report on characterized isolated compounds from the leaf of L. egregia and the occurrence of flavonols in the leaf
Large Scale Structure of the Universe
Galaxies are not uniformly distributed in space. On large scales the Universe
displays coherent structure, with galaxies residing in groups and clusters on
scales of ~1-3 Mpc/h, which lie at the intersections of long filaments of
galaxies that are >10 Mpc/h in length. Vast regions of relatively empty space,
known as voids, contain very few galaxies and span the volume in between these
structures. This observed large scale structure depends both on cosmological
parameters and on the formation and evolution of galaxies. Using the two-point
correlation function, one can trace the dependence of large scale structure on
galaxy properties such as luminosity, color, stellar mass, and track its
evolution with redshift. Comparison of the observed galaxy clustering
signatures with dark matter simulations allows one to model and understand the
clustering of galaxies and their formation and evolution within their parent
dark matter halos. Clustering measurements can determine the parent dark matter
halo mass of a given galaxy population, connect observed galaxy populations at
different epochs, and constrain cosmological parameters and galaxy evolution
models. This chapter describes the methods used to measure the two-point
correlation function in both redshift and real space, presents the current
results of how the clustering amplitude depends on various galaxy properties,
and discusses quantitative measurements of the structures of voids and
filaments. The interpretation of these results with current theoretical models
is also presented.Comment: Invited contribution to be published in Vol. 8 of book "Planets,
Stars, and Stellar Systems", Springer, series editor T. D. Oswalt, volume
editor W. C. Keel, v2 includes additional references, updated to match
published versio
Local steroid injection for moderately severe idiopathic carpal tunnel syndrome: Protocol of a randomized double-blind placebo-controlled trial (NCT 00806871)
<p>Abstract</p> <p>Background</p> <p>Patients with idiopathic carpal tunnel syndrome (CTS) are commonly treated with steroid injection into or proximal to the carpal tunnel. However, evidence for its efficacy beyond one month has not been established in randomized placebo-controlled trials. The primary aim of this randomized trial is to assess the efficacy of steroid injection into the carpal tunnel in relieving symptoms of CTS in patients with symptoms of such severity to warrant surgical treatment but have not been treated with steroid injection.</p> <p>Methods/Design</p> <p>The study is a randomized double-blind placebo-controlled trial. Patients referred to one orthopedic department because of CTS are screened. Eligibility criteria are age 18 to 70 years, clinical diagnosis of primary idiopathic CTS and abnormal nerve conduction tests or clinical diagnosis made independently by two orthopedic surgeons, failed treatment with wrist splinting, symptom severity of such magnitude that the patient is willing to undergo surgery, no severe sensory loss or thenar muscle atrophy, and no previous steroid injection for CTS. A total of 120 patients will be randomized to injection of 80 mg Methylprednisolone, 40 mg Methylprednisolone, or normal saline, each also containing 10 mg Lidocaine. Evaluation at baseline and at 5, 10, 24 and 52 weeks after injection includes validated questionnaires (CTS symptom severity scale, <it>Quick</it>DASH and SF-6D), adverse events, physical examination by a blinded assessor, and nerve conduction tests. The primary outcome measures are change in the CTS symptom severity score at 10 weeks and the rate of surgery at 52 weeks. The secondary outcome measures are the score change in the CTS symptom severity scale at 52 weeks, time to surgery, and change in <it>Quick</it>DASH and SF-6D scores and patient satisfaction at 10 and 52 weeks. The primary analysis will be carried out using mixed model analysis of repeated measures.</p> <p>Discussion</p> <p>This paper describes the rationale and design of a double-blind, randomized placebo-controlled trial that aims to determine the efficacy of two different doses of steroid injected into the carpal tunnel in patients with moderately severe idiopathic CTS.</p> <p>Trial registration</p> <p>Clinicaltrials.gov identifier NCT00806871</p
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