keyword
MENU ▼
Read by QxMD icon Read
search

Photo sensitivity

keyword
https://www.readbyqxmd.com/read/28525248/-magnetic-fields-and-health-from-epidemiology-to-cryptochrome-chemistry
#1
REVIEW
J Vanderstraeten
Biological effects of static magnetic fields (MF) and time-varying MF of electricity (50/60 Hz) appear possible from intensities in the low illitesla range. However, prolonged exposure to 50/60 Hz MF is associated with an increased risk of childhood leukemia at less than one microtesla of time-averaged intensity. And such kind of association is suggested in adults for some blood cancers and senile dementia. The cryptochrome hypothesis has been proposed to explain the association established with childhood leukemia...
2017: Revue Médicale de Bruxelles
https://www.readbyqxmd.com/read/28509539/tunable-luminescent-lanthanide-supramolecular-assembly-based-on-photoreaction-of-anthracene
#2
Yan Zhou, Heng-Yi Zhang, Zhi-Yuan Zhang, Yu Liu
Lanthanide luminescence materials generally show great superiority in light-emitting materials, gaining increasingly exploration in the design of advanced functional materials. Herein, we prepared a supramolecular assembly via the coordination of a host molecule (1) and dilanthanide metal. Compound 1 possesses a 9,10-diphenylanthracene (ant) core with photo-sensitivity and terminal terpyridine (tpy), containing two-arm dibenzo-24-crown-8. The assembly could exhibit excellent lanthanide luminescence after un-dergoing a photoreaction from anthracene unit in 1...
May 16, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28507663/molecular-engineering-and-sequential-cosensitization-for-preventing-the-trade-off-effect-with-photovoltaic-enhancement
#3
Weiwei Zhang, Yongzhen Wu, Xin Li, Erpeng Li, Xiongrong Song, Huiyun Jiang, Chao Shen, Hao Zhang, He Tian, Wei-Hong Zhu
In dye-sensitized solar cells (DSSCs), it is essential to use rational molecular design to obtain promising photosensitizers with well-matched energy levels and narrow optical band gaps. However, the "trade-off" effect between the photocurrent and photovoltage is still a challenge. Here we report four benzoxidazole based D-A-π-A metal-free organic dyes (WS-66, WS-67, WS-68 and WS-69) with different combinations of π-spacer units and anchoring-acceptor groups. Either extending the π-spacer or enhancing the electron acceptor can efficiently modulate the molecular energy levels, leading to a red-shift in the absorption spectra...
March 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28505443/defect-anti-perovskite-compounds-hg3q2i2-q-s-se-and-te-for-room-temperature-hard-radiation-detection
#4
Yihui He, Oleg Y Kontsevoi, Constantinos C Stoumpos, Giancarlo Trimarchi, Saiful M Islam, Zhifu Liu, Svetlana S Kostina, Sanjib Das, Bruce W Wessels, Mercouri G Kanatzidis, Joon-Il Kim, Wenwen Lin
The high Z chalcohalides Hg3Q2I2 (Q = S, Se and Te) can be regarded as anti-perovskite structure with ordered vacancies and are demonstrated to be very promising candidates for X- and γ-ray semiconductor detectors. Depending on Q the ordering of the Hg vacancies in these defect anti-perovskites varies and yields a rich family of distinct crystal structures ranging from zero-dimensional to three-dimensional, with a dramatic effect on the properties of each compound. All three Hg3Q2I2 compounds show very suitable optical, electrical, and good mechanical properties required for radiation detection at room temperature...
May 15, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28503778/a-topical-zinc-ionophore-blocks-tumorigenic-progression-in-uv-exposed-skh-1-high-risk-mouse-skin
#5
Rebecca Justiniano, Jessica Perer, Anh Hua, Mohammad Fazel, Andrea Krajisnik, Christopher M Cabello, Georg T Wondrak
Nonmelanoma skin cancer (NMSC) is the most common malignancy in the United States representing a considerable public health burden. Pharmacological suppression of skin photo-carcinogenesis has shown promise in preclinical and clinical studies, but more efficacious photochemopreventive agents are needed. Here, we tested feasibility of harnessing pharmacological disruption of intracellular zinc-homeostasis for photochemoprevention in vitro and in vivo. Employing the zinc-ionophore and FDA-approved microbicidal agent zinc pyrithione (ZnPT), used worldwide in over-the-counter (OTC) topical consumer products, we first demonstrated feasibility of achieving ZnPT-based intracellular Zn(2+) -overload in cultured malignant keratinocytes (HaCaT-ras II-4; SCC-25) employing membrane-permeable fluorescent probes...
May 15, 2017: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/28501197/methylmercury-determination-in-seafood-by-photochemical-vapor-generation-capacitively-coupled-plasma-microtorch-optical-emission-spectrometry
#6
Eniko Covaci, Marin Senila, Michaela Ponta, Eugen Darvasi, Dorin Petreus, Maria Frentiu, Tiberiu Frentiu
A non-chromatographic method based on double liquid-liquid extraction and measurements by UV photochemical vapor generation capacitively coupled plasma microtorch optical emission spectrometry was developed and characterized for methylmercury determination in seafood. Samples were prepared following the procedure recommended in JRC Technical Report of European Commission formerly proposed for the determination of methylmercury in seafood by thermal decomposition atomic absorption spectrometry, namely confinement of Hg species in 47% HBr solution, extraction of CH3Hg(+) in toluene and back-extraction in 1% l-cysteine aqueous solution...
August 1, 2017: Talanta
https://www.readbyqxmd.com/read/28500710/characterization-of-the-blue-light-activated-adenylyl-cyclase-mpac-by-flash-photolysis-and-ftir-spectroscopy
#7
Silke Kerruth, Pit Langner, Sarah Raffelberg, Wolfgang Gärtner, Joachim Heberle
The recently discovered photo-activated adenylyl cyclase (mPAC from Microcoleus chthonoplastes) is the first PAC that owes a light-, oxygen- and voltage-sensitive (LOV) domain for blue-light sensing. The photoreaction of the mPAC receptor was studied by time-resolved UV/vis and light-induced Fourier transform infrared (FTIR) absorption difference spectroscopy. The photocycle comprises of the typical triplet state LOV715 and the thio-adduct state LOV390 . While the adduct state decays with a time constant of 8 s, the lifetime of the triplet state is with 656 ns significantly shorter than in all other reported LOV domains...
May 2017: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/28500704/meta-analysis-of-the-transcriptome-reveals-a-core-set-of-shade-avoidance-genes-in-arabidopsis
#8
Romina Sellaro, Manuel Pacín, Jorge J Casal
The presence of neighboring vegetation modifies the light input perceived by photo-sensory receptors, initiating a signaling cascade that adjusts plant growth and physiology. Thousands of genes can change their expression during this process, but the structure of the transcriptional circuit is poorly understood. Here we present a meta-analysis of transcriptome data from Arabidopsis thaliana exposed to neighbor signals in different contexts, including organs where growth is promoted or inhibited by these signals...
May 2017: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/28497880/ambient-protection-of-few-layer-black-phosphorus-via-sequestration-of-reactive-oxygen-species
#9
Sumeet Walia, Sivacarendran Balendhran, Taimur Ahmed, Mandeep Singh, Christopher El-Badawi, Mathew D Brennan, Pabudi Weerathunge, Md Nurul Karim, Fahmida Rahman, Andrea Rassell, Jonathan Duckworth, Rajesh Ramanathan, Gavin E Collis, Charlene J Lobo, Milos Toth, Jimmy Christopher Kotsakidis, Bent Weber, Michael Fuhrer, Jose M Dominguez-Vera, Michelle J S Spencer, Igor Aharonovich, Sharath Sriram, Madhu Bhaskaran, Vipul Bansal
Few-layer black phosphorous (BP) has emerged as a promising candidate for next-generation nanophotonic and nanoelectronic devices. However, rapid ambient degradation of mechanically exfoliated BP poses challenges in its practical deployment in scalable devices. To date, the strategies employed to protect BP have relied upon preventing its exposure to atmospheric conditions. Here, an approach that allows this sensitive material to remain stable without requiring its isolation from the ambient environment is reported...
May 12, 2017: Advanced Materials
https://www.readbyqxmd.com/read/28488860/flexible-and-highly-photosensitive-electrolyte-gated-organic-transistors-with-ionogel-silver-nanowire-membranes
#10
Haihua Xu, Qingqing Zhu, Ying Lv, Kan Deng, Yinghua Deng, Qiaoliang Li, Suwen Qi, Wenwen Chen, Huisheng Zhang
Flexible and low-voltage photosensors with high near-infrared (NIR) sensitivity are critical for the realization of interacting humans with robots and environments by thermal imaging or night vision techniques. In this work, we for the first time develop an easy and cost-effective process to fabricate flexible and ultra-thin electrolyte-gated organic phototransistors (EGOPTs) with high transparent nanocomposite membranes involved of high-conductivity silver nanowire (AgNW) networks and large-capacitance iontronic films...
May 10, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28488762/visual-auras-in-epilepsy-and-migraine-an-analysis-of-clinical-characteristics
#11
Elisabeth Hartl, José António Gonzalez-Victores, Jan Rémi, Christoph J Schankin, Soheyl Noachtar
OBJECTIVE: To evaluate the characteristics of visual auras (VA) in epilepsy and migraine. BACKGROUND: Both disorders are usually diagnosed on clinical grounds, but differentiation might be challenging in isolated auras or because of the similar presentation in migraine and epilepsy. METHODS: A retrospective study of two cohorts was performed to compare the VA characteristics of 27 epilepsy patients and 27 age-matched migraine patients. RESULTS: The duration of VA was significantly shorter in epilepsy (median: 56s; 1st quartile Q1: 26s; 3rd quartile Q3: 130s) than in migraine (20 min; Q1: 10 min; Q3: 30 min) (P < ...
May 10, 2017: Headache
https://www.readbyqxmd.com/read/28486760/exceptionally-long-lived-photodriven-multi-electron-storage-without-sacrificial-reagents
#12
Martin Kuss-Petermann, Oliver S Wenger
Photo-excitation of a molecular pentad in presence of Sc3+ in de-aerated CH3CN leads to a quinone dianion that is stable on the millisecond timescale. Light-driven electron accumulation on the quinone unit is sensitized by two [Ru(bpy)3]2+ complexes in an intramolecular process, which relies on covalently attached triarylamine donors rather than on sacrificial reagents. Lewis acid - Lewis base interactions between Sc3+ and quinone dianion are responsible for the exceptionally long lifetime of this photoproduct...
May 9, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28486406/improving-visible-light-absorptivity-and-photoelectric-conversion-efficiency-of-a-tio%C3%A2-nanotube-anode-film-by-sensitization-with-bi%C3%A2-o%C3%A2-nanoparticles
#13
Menglei Chang, Huawen Hu, Yuyuan Zhang, Dongchu Chen, Liangpeng Wu, Xinjun Li
This study presents a novel visible light-active TiO₂ nanotube anode film by sensitization with Bi₂O₃ nanoparticles. The uniform incorporation of Bi₂O₃ contributes to largely enhancing the solar light absorption and photoelectric conversion efficiency of TiO₂ nanotubes. Due to the energy level difference between Bi₂O₃ and TiO₂, the built-in electric field is suggested to be formed in the Bi₂O₃ sensitized TiO₂ hybrid, which effectively separates the photo-generated electron-hole pairs and hence improves the photocatalytic activity...
May 9, 2017: Nanomaterials
https://www.readbyqxmd.com/read/28486203/properties-of-electronically-excited-states-of-four-squaraine-dyes-and-their-complexes-with-fullerene-c70-a-theoretical-investigation
#14
Jian Zhang, Tingyu Li
Solar cells sensitized by polypyridyl Ru(II) complexes exhibit relatively high efficiency, however those photo-sensitizers did not absorb the photons in the far-red and near-infrared region. At present, squaraine dyes have received considerable attention as their attractively intrinsic red light absorption and unusual high molar extinction coefficient. Here we applied density functional theory and time dependent density functional theory to investigate the properties of electronically excited states of four squaraine dyes and their complexes with fullerene C70...
May 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28482158/magnetically-guided-viral-transduction-of-gene-based-sensitization-for-localized-photodynamic-therapy-to-overcome-multidrug-resistance-in-breast-cancer-cells
#15
Zi-Xian Liao, Ivan M Kempson, Yu-Chen Fa, Meng-Chia Liu, Li-Chen Hsieh, Kuo-Yen Huang, Li-Feng Wang
Chemotherapy represents a conventional treatment for many cancers at different stages and is either solely prescribed or concomitant to surgery, radiotherapy, or both. However, treatment is tempered in instances of acquired drug resistance in response to either chemotherapy or targeted therapy, leading to therapeutic failure. To overcome this challenge, many studies focus on how cancer cells manipulate their genomes and metabolism to prevent drug influx and facilitate the efflux of accumulated chemotherapy drugs...
May 15, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28454020/toxicity-of-tio2-in-nanoparticle-or-bulk-form-to-freshwater-and-marine-microalgae-under-visible-light-and-uv-a-radiation
#16
M Sendra, I Moreno-Garrido, M P Yeste, J M Gatica, J Blasco
Use of titanium dioxide nanoparticles (TiO2 NPs) has become a part of our daily life and the high environmental concentrations predicted to accumulate in aquatic ecosystems are cause for concern. Although TiO2 has only limited reactivity, at the nanoscale level its physico-chemical properties and toxicity are different compared with bulk material. Phytoplankton is a key trophic level in fresh and marine ecosystems, and the toxicity provoked by these nanoparticles can affect the structure and functioning of ecosystems...
April 25, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28448042/imaging-the-neutrophil-phagosome-and-cytoplasm-using-a-ratiometric-ph-indicator
#17
Juliet R Foote, Adam P Levine, Philippe Behe, Michael R Duchen, Anthony W Segal
Neutrophils are crucial to host innate defense and, consequently, constitute an important area of medical research. The phagosome, the intracellular compartment where the killing and digestion of engulfed particles take place, is the main arena for neutrophil pathogen killing that requires tight regulation. Phagosomal pH is one aspect that is carefully controlled, in turn regulating antimicrobial protease activity. Many fluorescent pH-sensitive dyes have been used to visualize the phagosomal environment. S-1 has several advantages over other pH-sensitive dyes, including its dual emission spectra, its resistance to photo-bleaching, and its high pKa...
April 5, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28440292/visible-light-guided-manipulation-of-liquid-wettability-on-photoresponsive-surfaces
#18
Gibum Kwon, Divya Panchanathan, Seyed Reza Mahmoudi, Mohammed A Gondal, Gareth H McKinley, Kripa K Varanasi
Photoresponsive titania surfaces are of great interest due to their unique wettability change upon ultraviolet light illumination. However, their applications are often limited either by the inability to respond to visible light or the need for special treatment to recover the original wettability. Sensitizing TiO2 surfaces with visible light-absorbing materials has been utilized in photovoltaic applications. Here we demonstrate that a dye-sensitized TiO2 surface can selectively change the wettability towards contacting liquids upon visible light illumination due to a photo-induced voltage across the liquid and the underlying surface...
April 25, 2017: Nature Communications
https://www.readbyqxmd.com/read/28436646/filaments-with-affinity-binding-and-wet-strength-can-be-achieved-by-spinning-bifunctional-cellulose-nanofibrils
#19
Maija Vuoriluoto, Hannes Orelma, Meri Lundahl, Maryam Borghei, Orlando J Rojas
We demonstrate benzophenone (BP) conjugation via amine-reactive esters onto oxidized cellulosic fibers that were used as precursors, after microfluidization, of photoactive cellulose nanofibrils (CNF). From these fibrils, cellulose I filaments were synthesized by hydrogel spinning in an antisolvent followed by fast biradical UV cross-linking. As a result, the wet BP-CNF filaments retained extensively the original dry strength (a remarkable ∼80% retention). Thus, the principal limitation of these emerging materials was overcome (the wet tensile strength is typically <0...
May 3, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28430668/a-turn-on-fluorescent-probe-for-endogenous-formaldehyde-in-the-endoplasmic-reticulum-of-living-cells
#20
Yonghe Tang, Yanyan Ma, An Xu, Gaoping Xu, Weiying Lin
As the simplest aldehyde compounds, formaldehyde (FA) is implicated in nervous system diseases and cancer. Endoplasmic reticulum is an organelle that plays important functions in living cells. Accordingly, the development of efficient methods for FA detection in the endoplasmic reticulum (ER) is of great biomedical importance. In this work, we developed the first ER-targeted fluorescent FA probe Na-FA-ER. The detection is based on the condensation reaction of the hydrazine group and FA to suppress the photo-induced electron transfer (PET) pathway, resulting in a fluorescence increase...
April 21, 2017: Methods and Applications in Fluorescence
keyword
keyword
33361
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"