28,528 results match your criteria Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology[Journal]


Spectro-electrochemical Studies on [Ru(TAP)(dppz)]-Insights into the Mechanism of its Photosensitized Oxidation of Oligonucleotides.

Inorg Chem 2018 Dec 12. Epub 2018 Dec 12.

School of Chemical Sciences , Dublin City University , Dublin 9 , Ireland.

[Ru(TAP)(dppz)] (TAP = 1,4,5,8-tetraazaphenanthrene; dppz = dipyrido[3,2- a:2',3'- c]phenazine) is known to photo-oxidize guanine in DNA. Whether this oxidation proceeds by direct photoelectron transfer or by proton-coupled electron transfer is still unknown. To help distinguish between these mechanisms, spectro-electrochemical experiments have been carried out with [Ru(TAP)(dppz)] in acetonitrile. Read More

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December 2018

Organic bromine compounds produced in sea ice in Antarctic winter.

Nat Commun 2018 12 11;9(1):5291. Epub 2018 Dec 11.

Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, Serrano 119, 28006, Madrid, Spain.

During polar springtime, active bromine drives ozone, a greenhouse gas, to near-zero levels. Bromine production and emission in the polar regions have so far been assumed to require sunlight. Here, we report measurements of bromocarbons in sea ice, snow, and air during the Antarctic winter that reveal an unexpected new source of organic bromine to the atmosphere during periods of no sunlight. Read More

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December 2018

The Low Molecular Mass Photosystem II Protein PsbTn is Important for Light Acclimation.

Plant Physiol 2018 Dec 11. Epub 2018 Dec 11.

Umeå University CITY: Umea POSTAL_CODE: 90187 Sweden [SE]

Photosystem II (PSII) is a supramolecular complex containing over 30 protein subunits and a large set of cofactors including various pigments and quinones as well as Mn, Ca, Cl, and Fe ions. Eukaryotic PSII complexes contain many subunits not found in their bacterial counterparts, including the proteins PsbP, PsbQ, PsbS, and PsbW, as well as the highly homologous, low molecular mass subunits PsbTn1 and PsbTn2 whose function is currently unknown. To determine the function of PsbTn1 and PsbTn2, we generated single and double psbTn1 and psbTn2 knock-out mutants in Arabidopsis thaliana. Read More

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December 2018

Comparative physiological and proteomic analyses of the chloroplasts in halophyte Sesuvium portulacastrum under differential salt conditions.

J Plant Physiol 2018 Nov 16;232:141-150. Epub 2018 Nov 16.

Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou Hainan 571101, China; College of Life Sciences, Key Laboratory for Ecology of Tropical Islands, Ministry of Education, Hainan Normal University, Haikou, Hainan 571158, China. Electronic address:

Sesuvium portulacastrum, an important mangrove-associated true halophyte belongs to the family Aizoaceae, has excellent salt tolerance. Chloroplasts are the most sensitive organelles involved in the response to salinity. However, the regulation mechanism of chloroplasts of S. Read More

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November 2018

Substituent Effect on Metastable-State Photoacids: Design, Synthesis and Evaluation of their Photochemical Properties.

Chem Asian J 2018 Dec 7. Epub 2018 Dec 7.

UNITED STATES.

Recently, metastable-state photoacids have been widely used to control proton transfer in numerous chemical and biological processes as well as applications with visible light. Generally, substituent groups have great influence on photochemical properties of molecules, which will further affect their applications. Yet, substituent effect on the metastable-state photoacid has not been studied systematically. Read More

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December 2018

A designed protein binding-pocket to control excited-state intramolecular proton transfer fluorescence.

Org Biomol Chem 2018 Dec 7. Epub 2018 Dec 7.

Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.

Excited-state intramolecular proton transfer involves a photochemical isomerization and creates the opportunity for the emission of two distinct wavelengths of light from a single fluorophore. The selectivity between these two wavelengths of emission is dependent on the environment around the fluorophore and suggests the possibility for ratiometric monitoring of protein microenvironments. Unfortunately, nonspecific binding of ESIPT fluorophores does not often lead to dramatic changes in the ratio between the two wavelengths of emission. Read More

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December 2018

Elevated CO Improves Photosynthesis Under High Temperature by Attenuating the Functional Limitations to Energy Fluxes, Electron Transport and Redox Homeostasis in Tomato Leaves.

Front Plant Sci 2018 26;9:1739. Epub 2018 Nov 26.

Department of Horticulture, Zhejiang University, Hangzhou, China.

Elevated atmospheric CO improves leaf photosynthesis and plant tolerance to heat stress, however, the underlying mechanisms remain unclear. In this study, we exposed tomato plants to elevated CO (800 μmol mol) and/or high temperature (42°C for 24 h), and examined a range of photosynthetic and chlorophyll fluorescence parameters as well as cellular redox state to better understand the response of photosystem II (PSII) and PSI to elevated CO and heat stress. The results showed that, while the heat stress drastically decreased the net photosynthetic rate (P), maximum carboxylation rate (), maximum ribulose-1,5-bis-phosphate (RuBP) regeneration rate () and maximal photochemical efficiency of PSII (F/F), the elevated CO improved those parameters under heat stress and at a 24 h recovery. Read More

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November 2018

Protective effects of ginsenoside Rg2 and astaxanthin mixture against UVB-induced DNA damage.

Anim Cells Syst (Seoul) 2018 9;22(6):400-406. Epub 2018 Oct 9.

Research Institute for Basic Science and Division of Biological Science, Wonkwang University, Iksan, Korea.

Ultraviolet B (UVB) radiation induces skin damage, skin matrix degradation, and wrinkle formation through photochemical reaction and oxidative stress. Therefore, protecting the skin from UVB can prevent skin aging. In this study, we investigated the effects of a mixture (RA) of Rg2, a ginsenoside, and astaxanthin, an antioxidant, on the responses of HaCaT cells exposed to UVB (700 J/m). Read More

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October 2018
1 Read

The effect of ozone fumigation on the biogenic volatile organic compounds (BVOCs) emitted from Brassica napus above- and below-ground.

PLoS One 2018 10;13(12):e0208825. Epub 2018 Dec 10.

Institute of Ion and Applied Physics, University of Innsbruck, Innsbruck, Austria.

The emissions of BVOCs from oilseed rape (Brassica napus), both when the plant is exposed to clean air and when it is fumigated with ozone at environmentally-relevant mixing ratios (ca. 135 ppbv), were measured under controlled laboratory conditions. Emissions of BVOCs were recorded from combined leaf and root chambers using a recently developed Selective Reagent Ionisation-Time of Flight-Mass Spectrometer (SRI-ToF-MS) enabling BVOC detection with high time and mass resolution, together with the ability to identify certain molecular functionality. Read More

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December 2018

Sensing with Photoluminescent Semiconductor Quantum Dots.

Methods Appl Fluoresc 2018 Dec 7. Epub 2018 Dec 7.

Biomedical Engineering, Boston University, Boston, Massachusetts, UNITED STATES.

Fluorescent sensors benefit from high signal-to-noise and multiple measurement modalities, allowing for a multitude of applications and flexibility of design. Semiconductor nanocrystal quantum dots (QDs) are excellent fluorophores for sensors because of their extraordinary optical properties. They have high thermal and photochemical stability compared to organic dyes or fluorescent proteins and are extremely bright due to their large molar cross-sections. Read More

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December 2018

Photochemical study of a cyanobacterial chloride-ion pumping rhodopsin.

Biochim Biophys Acta Bioenerg 2018 Dec 6. Epub 2018 Dec 6.

Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan; Global Station for Soft Matter, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo 060-0810, Japan.

Mastigocladopsis repens halorhodopsin (MrHR) is a Cl-pumping rhodopsin that belongs to a distinct cluster far from other Cl pumps. We investigated its pumping function by analyzing its photocycle and the effect of amino acid replacements. MrHR can bind I similar to Cl but cannot transport it. Read More

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December 2018

A thermophilic microorganism from Deception Island, Antarctica with a thermostable glutamate dehydrogenase activity.

Biol Res 2018 Dec 8;51(1):55. Epub 2018 Dec 8.

Fundación Científica y Cultural Biociencia, José Domingo Cañas 2280, Santiago, 7750132, Chile.

Background: The Antarctic continent is a source of extreme microorganisms. Millions of years of isolation have produced unique biodiversity with adaptive responses to its extreme environment. Although the Antarctic climate is mainly cold, the presence of several geothermal sites, including thermal springs, fumaroles, hot soils and hydrothermal vents, provides ideal environments for the development of thermophilic and hyperthermophilic microorganisms. Read More

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December 2018

Dicarboxylic acids and related compounds in PM aerosols in Huangshi, central China.

J Air Waste Manag Assoc 2018 Dec 10. Epub 2018 Dec 10.

a Hubei Key Laboratory of Mine Environmental Pollution Control & Remediation, School of Environmental Science and Engineering, Hubei Polytechnic University , Huangshi , China.

PM samples were collected in Huangshi (HS), central China from March 2012 to February 2013 and were analyzed for dicarboxylic acids (diacids) and related compounds (DARCs). Oxalic acid (C, 416 ng m) was the most abundant species, followed by phthalic (Ph, 122 ng m), terephthalic (tPh, 116 ng m), succinic (C, 70.4 ng m), azelaic (C, 67. Read More

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December 2018

Photochemical resolution of a thermally inert cyclometalated Ru(phbpy)(N-N)(sulfoxide)+ complex.

J Am Chem Soc 2018 Dec 11. Epub 2018 Dec 11.

In this work a photosubstitution strategy is presented that can be used for the isolation of chiral organometallic complexes. A series of five cyclometalated complexes [Ru(phbpy)(N-N)(DMSO-κS)]+ ([1]PF6-[5]PF6) were synthesized and characterized, where Hphbpy = 6'-phenyl-2,2'-bipyridyl, and N-N = bpy (2,2'-bipyridine), phen (1,10-phenanthroline), dpq (pyrazino[2,3-f][1,10]phenanthroline), dppz (dipyrido[3,2-a:2',3'-c]phenazine, or dppn (benzo[i]dipyrido[3,2-a:2',3'-c]phenazine), respective-ly. Due to the asymmetry of the cyclometalated phbpy- ligand, the corresponding [Ru(phbpy)(N-N)(DMSO-κS)]+complexes are chiral. Read More

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December 2018

Confinement of Singlet Oxygen Generated from Ruthenium Complex-Based Oxygen Sensor in the Pores of Mesoporous Silica Nanoparticles.

Bioconjug Chem 2018 Dec 10. Epub 2018 Dec 10.

Department of Chemistry and Biological Science, College of Science and Engineering , Aoyama Gakuin University , 5-10-1 Fuchinobe , Chuo-ku, Sagamihara , 252-5258 , Japan.

We synthesized mesoporous silica nanoparticles bearing ruthenium complexes in their pores (MSN-Ru) and characterized their photochemical properties. The ruthenium complexes that were immobilized in the pores showed oxygen-dependent phosphorescence, similar to the complexes that were not tethered to nanoparticles. Cellular imaging and in vivo experiments revealed that hypoxic cells and tissues could be visualized by monitoring the phosphorescence of MSN-Ru. Read More

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December 2018

Point-of-Care Tissue Analysis Using Miniature Mass Spectrometer.

Anal Chem 2018 Dec 10. Epub 2018 Dec 10.

The combination of direct sampling ionization and miniature mass spectrometer presents a promising technical pathway of point-of-care (POC) analysis in clinical applications. In this work, a miniature mass spectrometry system was used for analysis of tissue samples. Direct tissue sampling coupled with extraction spray ionization was used with a homebuilt miniature mass spectrometer, Mini 12. Read More

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December 2018
5.636 Impact Factor

Methane production and emissions in trees and forests.

New Phytol 2018 Dec 6. Epub 2018 Dec 6.

Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD, 21037.

Forest ecosystem methane (CH ) research has focused on soils, but trees are also important sources and sinks in forest CH budgets. Living and dead trees transport and emit CH produced in soils; living trees and deadwood emit CH produced inside trees by microorganisms; and trees produce CH through an abiotic photochemical process. Here, we review the state of the science on the production, consumption, transport, and emission of CH by living and dead trees, and the spatial and temporal dynamics of these processes across hydrologic gradients inclusive of wetland and upland ecosystems. Read More

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December 2018
5 Reads

Responses of Morphology, Gas Exchange, Photochemical Activity of Photosystem II, and Antioxidant Balance in to Light Spectra.

Front Plant Sci 2018 21;9:1704. Epub 2018 Nov 21.

College of Forestry, Nanjing Forestry University, Nanjing, China.

Light quality is a critical factor regulating photosynthetic capacity which directly affects the final yield of plants. is a multiple function tree species and its leaves are widely used as tea production and ingredient in functional foods in China. However, the effects of varying light quality on photosynthetic process and the photoprotective mechanisms remains unexplored in-depth. Read More

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November 2018
1 Read

Dissymmetry enhancement in enantioselective synthesis of helical polydiacetylene by application of superchiral light.

Nat Commun 2018 11 30;9(1):5117. Epub 2018 Nov 30.

CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, 230026, Hefei, Anhui, China.

Superchiral light, generated by the interference of two counter-propagating circularly polarized light (CPL) with same frequency, opposite handedness and different intensity, exhibits enhanced dissymmetry in its interaction with chiral molecules, and has the potential for ultrasensitive detection and characterization of chiral molecules. It is anticipated that the enhanced optical dissymmetry in superchiral light (SCL) field may be utilized to promote asymmetric photochemical reactions efficiency. Herein we reported SCL impart greater chiral bias to trigger asymmetric photo-polymerization reaction from initially achiral diacetylene (DA) monomer, and the enhanced optical dissymmetry for whole polydiacetylene (PDA) films could be achieved. Read More

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November 2018

A Fast Photochemical Oxidation of Proteins (FPOP) platform for free-radical reactions: the carbonate radical anion with peptides and proteins.

Free Radic Biol Med 2018 Nov 28;131:126-132. Epub 2018 Nov 28.

Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA. Electronic address:

Fast Photochemical Oxidation of Protein (FPOP), based on a pulsed KrF laser (248 nm) for free-radical generation, is a biophysical method that utilizes hydroxyl radicals to footprint proteins in solution. FPOP has been recognized for structural proteomics investigations, including epitope mapping, protein-aggregation characterization, protein-folding monitoring, and binding-affinity determination. The distinct merits of the platform are: i) the use of a scavenger to control radical lifetime and allow fast ("snapshot") footprinting of solvent-accessible residues in a protein; ii) the employment of a flow system to enable single-shot irradiation of small plugs of the targeted sample; iii) the use of methionine and catalase after radical oxidation chemistry to prevent post-oxidation with residual oxidizing species; and iv) the utilization of mature mass spectrometry-based proteomic methods to afford detailed analysis. Read More

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November 2018

Invited Review Article: Photofragment imaging.

Authors:
Arthur G Suits

Rev Sci Instrum 2018 Nov;89(11):111101

Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA.

Photodissociation studies in molecular beams that employ position-sensitive particle detection to map product recoil velocities emerged thirty years ago and continue to evolve with new laser and detector technologies. These powerful methods allow application of tunable laser detection of single product quantum states, simultaneous measurement of velocity and angular momentum polarization, measurement of joint product state distributions for the detected and undetected products, coincident detection of multiple product channels, and application to radicals and ions as well as closed-shell molecules. These studies have permitted deep investigation of photochemical dynamics for a broad range of systems, revealed new reaction mechanisms, and addressed problems of practical importance in atmospheric, combustion, and interstellar chemistry. Read More

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November 2018

Excited-State Switching between Ligand-Centered and Charge Transfer Modulated by Metal-Carbon Bonds in Cyclopentadienyl Iridium Complexes.

Inorg Chem 2018 Dec 5. Epub 2018 Dec 5.

Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States.

Three series of pentamethylcyclopentadienyl (Cp*) Ir(III) complexes with different bidentate ligands were synthesized and structurally characterized, [Cp*Ir(tpy)L] (tpy = 2-tolylpyridinato; n = 0 or 1), [Cp*Ir(piq)L] (piq = 1-phenylisoquinolinato; n = 0 or 1), and [Cp*Ir(bpy)L] (bpy = 2,2'-bipyridine; m = 1 or 2), featuring a range of monodentate carbon-donor ligands within each series [L = 2,6-dimethylphenylisocyanide; 3,5-dimethylimidazol-2-ylidene (NHC); methyl)]. The spectroscopic and photophysical properties of these molecules and those of the photocatalyst [Cp*Ir(bpy)H] were examined to establish electronic structure-photophysical property relationships that engender productive photochemical reactivity of this hydride and its methyl analogue. The Ir(III) chromophores containing ancillary CNAr ligands exhibited features anticipated for predominantly ligand-centered (LC) excited states, and analogues bearing the NHC ancillary exhibited properties consistent with LC excited states containing a small admixture of metal-to-ligand charge-transfer (MLCT) character. Read More

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December 2018
3 Reads

Radiochemistry in a flash: photochemical conjugation and one-pot radiolabelling of antibodies for immuno-PET.

Angew Chem Int Ed Engl 2018 Dec 5. Epub 2018 Dec 5.

Univeristy of Zürich, Department of Chemistry, Winterthurerstrasse 190, CH-8057, Zürich, SWITZERLAND.

Monoclonal antibodies (mAbs), immunoglobulin fragments and other proteins are important scaffolds in the development of radiopharmaceuticals for diagnostic immuno-positron emission tomography (immuno-PET) and targeted radioimmunotherapy (RIT). Conventional methods for radiolabelling proteins with metal ions like 68Ga, 64Cu, 89Zr, and 90Y etc require multi-step procedures involving pre-purification, functionalisation with a chelate, and subsequent radiolabelling. Standard coupling chemistries are time consuming, difficult to automate, and involve synthesis, isolation and storage of an intermediate, new molecular entity (the conjugated mAb) whose biochemical properties can differ from those of the parent protein. Read More

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December 2018

A field portable method for the semi-quantitative estimation of dehydration tolerance of photosynthetic tissues across distantly related land plants.

Physiol Plant 2018 Dec 4. Epub 2018 Dec 4.

University of the Basque Country, Dpt. Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n 48940, Leioa, Spain.

Desiccation tolerant (DT) plants withstand complete cellular dehydration, reaching relative water contents (RWC) below 30% in their photosynthetic tissues. Desiccation sensitive (DS) plants exhibit different degrees of dehydration tolerance (DHT), never surviving water loss >70%. To date, no procedure for the quantitative evaluation of DHT extent exists that is able to discriminate DS species with differing degrees of DHT from truly DT plants. Read More

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December 2018

Membrane reorganization after photochemical internalization to release transferrin-biofunctionalized polystyrene microparticles.

Sci Rep 2018 Dec 4;8(1):17617. Epub 2018 Dec 4.

Unitat de Biologia Cel·lular, Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.

Therapeutic drug carriers can drive their cargo to their target cells. However, an obstacle is usually the entrapment of the drug inside the endolysosomal compartment, which physically impedes its actuation by the impossibility of reaching its molecular site of action. To overcome this hurdle, photochemical internalization (PCI) has been proposed, but the extent of PCI-induced membrane disruption and its capability to allow the release of microparticles is unknown. Read More

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December 2018

Photochemically Active Dyes for Super-Resolution Microscopy.

Chimia (Aarau) 2018 Nov;72(11):764-770

Laboratorium für Organische Chemie ETH Zurich Vladimir-Prelog-Weg 3, CH-8093 Zurich;, Email:

The development of super-resolved optical microscopies has revolutionized the way we visualize cell biology. These techniques strongly rely on the use of photochemically active fluorophores that display changes in their photophysical properties upon irradiation with light. Many reversible and irreversible photochemical transformations have been explored for this purpose, and different imaging techniques require specific mechanisms of photoconversion. Read More

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November 2018

Inorganic Salts and Antimicrobial Photodynamic Therapy: Mechanistic Conundrums?

Molecules 2018 Dec 3;23(12). Epub 2018 Dec 3.

Laser Research Centre, Faculty of Health Science, University of Johannesburg, Johannesburg, Doornfontein 2028, South Africa.

We have recently discovered that the photodynamic action of many different photosensitizers (PSs) can be dramatically potentiated by addition of a solution containing a range of different inorganic salts. Most of these studies have centered around antimicrobial photodynamic inactivation that kills Gram-negative and Gram-positive bacteria in suspension. Addition of non-toxic water-soluble salts during illumination can kill up to six additional logs of bacterial cells (one million-fold improvement). Read More

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December 2018

Time-Resolved Spectroscopic Study of ,-Di(4-bromo)nitrenium Ions in Selected Solutions.

Molecules 2018 Dec 3;23(12). Epub 2018 Dec 3.

Department of Chemistry, The University of Hong Kong, Hong Kong S.A.R., China.

Nitrenium ions are important reactive intermediates in chemistry and biology. In this work, femtosecond and nanosecond transient absorption (fs-TA and ns-TA) along with nanosecond time-resolved resonance Raman (ns-TR³) experiments were employed to examine the photochemical pathways of -(4,4'-dibromodiphenylamino)-2,4,6-trimethylpyridinium BF₄ (salt (DN) from just absorption of a photon of light to the production of the important ,-di(4-bromophenyl)nitrenium ion . In acetonitrile (MeCN), the formation of halogenated diarylnitrenium ion was observed within 4 ps, showing the vibrational spectra with strong intensity. Read More

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December 2018

Observations of C-C alkyl nitrates in the Yellow River Delta, northern China: Effects of biomass burning and oil field emissions.

Sci Total Environ 2018 Nov 15;656:129-139. Epub 2018 Nov 15.

Environment Research Institute, Shandong University, Ji'nan, Shandong, China; Ji'nan Institute of Environmental Science, Ji'nan, Shandong, China. Electronic address:

Alkyl nitrates (RONO) are important reservoirs of nitrogen oxides and play key roles in the tropospheric chemistry. Two phases of intensive campaigns were conducted during February-April and June-July of 2017 at a rural coastal site and in open oil fields of the Yellow River Delta region, northern China. C-C alkyl nitrates showed higher concentration levels in summer than in winter-spring (p < 0. Read More

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November 2018
1 Read

Low-Energy Chlorophylls in Fucoxanthin Chlorophyll a/c-Binding Protein Conduct Excitation Energy Transfer to Photosystem I in Diatoms.

J Phys Chem B 2018 Dec 4. Epub 2018 Dec 4.

Photosynthetic organisms handle solar energy precisely to achieve efficient photochemical reactions. Since there are a wide variety of light-harvesting antennas in oxyphototrophs, the excitation-energy-transfer mechanisms are thought to differ significantly. In this study, we compared excitation-energy dynamics between photosystem I (PSI) cores and a complex between PSI and fucoxanthin chlorophyll a/c-binding protein (PSI-FCPI) isolated from a diatom, Chaetoceros gracilis, by means of picosecond time-resolved fluorescence analyses. Read More

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December 2018

Photochemical generation of radicals from alkyl electrophiles using a nucleophilic organic catalyst.

Nat Chem 2018 Dec 3. Epub 2018 Dec 3.

ICIQ, Institute of Chemical Research of Catalonia-the Barcelona Institute of Science and Technology, Tarragona, Spain.

Chemists extensively use free radical reactivity for applications in organic synthesis, materials science, and life science. Traditionally, generating radicals requires strategies that exploit the bond dissociation energy or the redox properties of the precursors. Here, we disclose a photochemical catalytic approach that harnesses different physical properties of the substrate to form carbon radicals. Read More

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December 2018

Photo-crosslinkable, bone marrow-derived mesenchymal stem cells-encapsulating hydrogel based on collagen for osteogenic differentiation.

Colloids Surf B Biointerfaces 2018 Nov 22;174:528-535. Epub 2018 Nov 22.

CAS Key Laboratory for Nano-Bio Interface, Division of Nanobiomedicine, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China; School of Nano Technology and Nano Bionics, University of Science and Technology of China, Hefei, 230026, China. Electronic address:

Many patients suffer from bone injury and self-regeneration is not effective. Developing new strategies for effective bone injury repair is highly desired. Herein, collagen, an important component of the extracellular matrix, was modified with glycidyl methacrylate. Read More

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November 2018
1 Read

Impacts of photochemical ageing on the half-lives and diagnostic ratio of polycyclic aromatic hydrocarbons intrinsic to PM collected from 'real-world' like combustion events of wood and rice straw burning.

J Hazard Mater 2018 Nov 22;366:10-15. Epub 2018 Nov 22.

Environmental Sciences Section, Bose Institute, P 1/12 CIT Scheme VII-M, Kolkata, 700054, India; Centre for Astroparticle Physics and Space Science, Block-EN, Sector-V, Salt Lake, Kolkata, 700091, India; Department of Physics, Bose Institute, 93/1, A.P.C Road, Kolkata, 700009, India. Electronic address:

The present experimental study describes the characteristics of polycyclic aromatic hydrocarbons (PAHs) emitted with PM particles during wood and rice straw burning as well as impacts of photochemical ageing on the half lives of particulate PAHs and their diagnostic ratio values. The photochemical degradation kinetics experiments were carried out by exposing the PM to light and synthetic air flow. Pseudo first order rate constants were calculated based on PAH loss as a function of exposure time. Read More

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November 2018
2 Reads

Photo-dependent somatic embryogenesis from non-embryogenic calli and its polyphenolics content in high-valued medicinal plant of Ajuga bracteosa.

J Photochem Photobiol B 2018 Nov 20;190:59-65. Epub 2018 Nov 20.

Department of Horticulture, The University of Agriculture, Peshawar, Peshawar 25120, Pakistan.

Ajuga bracteosa (A. bracteosa) is one of the critically endangered and high-valued medicinal plants worldwide. Light is one of the major factor or stimulus involved in the morphogenic responses and bioactive compounds production in various medicinal plants. Read More

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November 2018

Mesohaline conditions represent the threshold for oxidative stress, cell death and toxin release in the cyanobacterium Microcystis aeruginosa.

Aquat Toxicol 2018 Nov 22;206:203-211. Epub 2018 Nov 22.

Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL, 32224, USA.

As aquatic ecosystems become increasingly affected by hydrologic alterations, drought and sea level rise a need exists to better understand the biological effects of elevated salinity on toxigenic cyanobacteria such as Microcystis aeruginosa. This study investigated the impacts of oligohaline/low mesohaline conditions and exposure time on selected physiological and biochemical responses in M. aeruginosa including cell viability, oxidative stress, antioxidant responses, in addition to microcystin synthesis and release into the surrounding environment. Read More

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November 2018

Nitrate Removal via Formate Radical-induced Photochemical Process.

Environ Sci Technol 2018 Nov 30. Epub 2018 Nov 30.

Removal of excess nitrate is critical to balance the nitrogen cycle in aquatic systems. This study investigated a novel denitrification process by tailoring photochemistry of nitrate with formate. Under UV light irradiation, short-lived radicals (i. Read More

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November 2018
1 Read

Synthesis and in vitro anti-platelet aggregation activities of 2-methoxy-5-arylamido-N-(pyridin-3-yl-methyl)benzamides.

Arch Pharm (Weinheim) 2018 Nov 30:e1800257. Epub 2018 Nov 30.

Tianjin University of Technology, Tianjin, People's Republic of China.

In order to discover novel compounds with anti-platelet aggregation activities, a series of novel 2-methoxy-5-arylamido-N-(pyridin-3-ylmethyl)benzamides (1a-n) were synthesized and their anti-platelet aggregation activities were evaluated by the turbidimetric method in response to the following agonists: adenosine diphosphate (ADP) (5 mM/L), arachidonic acid (AA) (20 µM/L), and collagen (1 mg/mL). Those synthesized compounds that have better in vitro activities were subjected to cell toxicity tests via cell counting kit-8 (CCK-8) assay. The biological evaluation revealed that compound 1a (IC : 0. Read More

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November 2018
1 Read

Thermochromism from Ultrathin Colloidal Sb Se Nanowires Undergoing Reversible Growth and Dissolution in an Amine-Thiol Mixture.

Adv Mater 2018 Nov 29:e1806164. Epub 2018 Nov 29.

Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.

Liquid-based thermochromics can be incorporated into an arbitrarily shaped container and provide a visual map of the temperature changes within its volume. However, photochemical degradation, narrow temperature range of operation, and the need for stringent encapsulation processes are challenges that can limit their widespread use. Here, a unique solution-based thermochromic comprising ultrathin colloidal Sb Se nanowires in an amine-thiol mixture is introduced. Read More

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November 2018
1 Read

Luminescence and reactivity of a charge-transfer excited iron complex with nanosecond lifetime.

Science 2018 Nov 29. Epub 2018 Nov 29.

Center for Analysis and Synthesis (CAS), Department of Chemistry, Lund University, Box 124, SE-22100 Lund, Sweden.

Iron's abundance and rich coordination chemistry are potentially appealing features for photochemical applications. However, the photoexcitable charge-transfer (CT) states of most Fe complexes are limited by picosecond or sub-picosecond deactivation through low-lying metal centered (MC) states, resulting in inefficient electron transfer reactivity and complete lack of photoluminescence. Here we show that octahedral coordination of Fe(III) by two mono-anionic facial -carbene ligands can suppress such deactivation dramatically. Read More

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November 2018

A Pentacene-based Nanotube Displaying Enriched Electro/Photochemical Activities.

Angew Chem Int Ed Engl 2018 Nov 29. Epub 2018 Nov 29.

Tokyo Institute of Technology, Laboratory for Chemistry and Life Science, Institute of Innovative Research, 4259-R28, Nagatsuta, Midori-ku, 226-8503, Yokohama, JAPAN.

Unlike previously well-studied, acyclic pentacene oligomers, here we report the first synthesis of a cyclic pentacene trimer with a fixed tubular conformation. A short-step synthesis starting from common pentacenequinone yielded the target molecule with a 1.5-nanometer length and a subnanometer pore. Read More

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November 2018

Thieno[3,2-b]indole-based hole transporting materials for perovskite solar cells with photovoltages exceeding 1.11 V.

Chem Commun (Camb) 2018 Dec;54(99):14025-14028

Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, Department of Applied Chemistry, Tianjin University of Technology, Tianjin 300384, P. R. China.

Four new hole transporting materials (HTMs), M107-M110, based on thieno[3,2-b]indole cores have been designed and employed in perovskite solar cells. The perovskite solar cells based on M109 exhibit a leading efficiency of 18.14% with a photovoltage over 1. Read More

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December 2018
2 Reads

Defect-Induced Pt-Co-Se Coordinated Sites with Highly Asymmetrical Electronic Distribution for Boosting Oxygen-Involving Electrocatalysis.

Adv Mater 2018 Nov 28:e1805581. Epub 2018 Nov 28.

School of Environment and Sciences, and Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan Campus, Nathan, 4111, Australia.

Rational design and synthesis of hetero-coordinated moieties at the atomic scale can significantly raise the performance of the catalyst and obtain mechanistic insight into the oxygen-involving electrocatalysis. Here, a facile plasma-photochemical strategy is applied to construct atomically coordinated Pt-Co-Se moieties in defective CoSe (CoSe ) through filling the plasma-created Se vacancies in CoSe with single Pt atomic species (CoSe -Pt) under ultraviolet irradiation. The filling of single Pt can remarkably enhance the oxygen evolution reaction (OER) activity of CoSe . Read More

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November 2018
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Chloroplastic ATP Synthase Alleviates Photoinhibition of Photosystem I in Tobacco Illuminated at Chilling Temperature.

Front Plant Sci 2018 14;9:1648. Epub 2018 Nov 14.

Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.

Chloroplastic ATP synthase plays a significant role in the regulation of proton motive force () and proton gradient (ΔpH) across the thylakoid membranes. However, the regulation of chloroplastic ATP synthase at chilling temperature and its role in photoprotection are little known. In our present study, we examined the chlorophyll fluorescence, P700 signal, and electrochromic shift signal at 25°C, and 6°C in tobacco ( L. Read More

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November 2018

Phenotype Regulation of Smooth Muscle Cells Through Facial Crystallization of Poly(-Caprolactone).

J Nanosci Nanotechnol 2019 Apr;19(4):2269-2275

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

Phenotype conversion of smooth muscle cells (SMCs) plays a key role in the formation of atherosclerosis. Understanding how SMCs respond to a micro/nano-topology and elucidating the cellular mechanism of phenotype conversion is critical to the atherosclerosis treatment. Herein, we prepared poly(-caprolactone) (PCL) spherulites with a radius more than 350 m for the studying of radial microstructure influence on SMCs behaviors. Read More

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April 2019
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Application of Gold-Nanoparticle Colorimetric Sensing to Rapid Food Safety Screening.

Sensors (Basel) 2018 Nov 27;18(12). Epub 2018 Nov 27.

Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Vegetables Quality and Safety Control, Ministry of Agriculture and Rural Affairs of China, Beijing 100081, China.

Due to their unique optical properties, narrow size distributions, and good biological affinity, gold nanoparticles have been widely applied in sensing analysis, catalytic, environmental monitoring, and disease therapy. The color of a gold nanoparticle solution and its maximum characteristic absorption wavelength will change with the particle size and inter-particle spacing. These properties are often used in the detection of hazardous chemicals, such as pesticide residues, heavy metals, banned additives, and biotoxins, in food. Read More

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November 2018

Formation of Subwavelength Periodic Triangular Arrays on Tungsten through Double-Pulsed Femtosecond Laser Irradiation.

Materials (Basel) 2018 Nov 26;11(12). Epub 2018 Nov 26.

State Key Laboratory of Applied Optics, Changchun Institute of Modern Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.

We present a mask-free strategy for fabricating two-dimensional subwavelength periodic triangular arrays on tungsten, by focusing two orthogonally polarized and temporally delayed femtosecond laser beams using a cylindrical lens. In stark contrast to the commonly observed structures of either a single ablation spot or a one-dimensional grating, we obtained highly uniform periodic triangular arrays on the laser-exposed surface, with three equilateral sides each of 480 nm in length and about 100 nm in modulation depth. The triangular features varied with both the laser energy and the scanning speed. Read More

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November 2018

Spatially resolved covalent functionalization patterns on graphene.

Angew Chem Int Ed Engl 2018 Nov 28. Epub 2018 Nov 28.

J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dpt. of Low-dimensional systems, Dolejškova 2155/3, 18223, Prague, CZECH REPUBLIC.

Spatially resolved functionalization of 2-D materials is highly demanded but very challenging to achieve. The chemical patterning is typically tackled by preventing contact between the reagent and material, with various accompanying challenges. Photochemical transformation on the other hand inherently provides remote high spatiotemporal resolution using the cleanest reagent - a photon. Read More

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November 2018

Synthesis of Re(I) Rings Comprising Different Re(I) Units and Their Light-Harvesting Abilities.

Inorg Chem 2018 Nov 28. Epub 2018 Nov 28.

Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1-NE-1, O-okayama , Meguro-ku , Tokyo 152-8550 , Japan.

Trimethylamine N-oxide (MeNO) could selectively remove only one CO ligand from fac-[Re(N^N)(CO)(PRR')] (N^N = diimine ligand), whereby only the CO ligand in the trans position to the phosphorus ligand was selectively removed to give cis,trans-[Re(N^N)(CO)(PRR')(L)] in good yields. This decarbonylation reaction using MeNO was found to be especially useful for synthesizing biscarbonyl Re(I) complexes with electron-withdrawing groups in the diimine ligand, which could not be synthesized or were obtained only in low yields by the photochemical method. MeNO also selectively removed the carbonyl ligands in the trans position to the phosphorus ligands from the edge Re(I) complex units, which have the fac-[Re(N^N)(CO)(PRR')] structure, in linear-shaped Re(I) multinuclear complexes. Read More

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November 2018

Protein Footprinting with Radical Probe Mass Spectrometry - Two Decades of Achievement.

Protein Pept Lett 2018 Nov 28. Epub 2018 Nov 28.

University of New South Wales - Infectious Disease Responses Laboratory, Prince of Wales Clinical School Sydney. Australia.

Background: Radical Probe Mass Spectrometry (RP-MS) describes a pioneering methodology in structural biology that enables the study of protein structures, their interactions, and dynamics on fast timescales (down to sub-milliseconds). Hydroxyl radicals (•OH) generated directly from water within aqueous solutions induce the oxidation of reactive, solvent accessible amino acid side chains that are then analyzed by mass spectrometry. Introduced in 1998 at the American Society for Mass Spectrometry annual conference, RP-MS was first published on in 1999. Read More

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November 2018
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