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https://www.readbyqxmd.com/read/28231634/from-endogenous-to-exogenous-pattern-formation-invasive-plant-species-changes-the-spatial-distribution-of-a-native-ant
#1
Kevin Li, Yifan He, Susanna K Campbell, A Shawn Colborn, Eliot L Jackson, Austin Martin, Ivan V Monagan, Theresa Wei Ying Ong, Ivette Perfecto
Invasive species are a significant threat to global biodiversity, but our understanding of how invasive species impact native communities across space and time remains limited. Based on observations in an old field in Southeast Michigan spanning 35 years, our study documents significant impacts of habitat change, likely driven by the invasion of the shrub, Elaeagnus umbellata, on the nest distribution patterns and population demographics of a native ant species, Formica obscuripes. Landcover change in aerial photos indicates that E...
February 23, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28231315/functional-xanthophyll-cycle-and-pigment-content-of-a-kleptoplastic-benthic-foraminifer-haynesina-germanica
#2
Thierry Jauffrais, Bruno Jesus, Vona Méléder, Emmanuelle Geslin
Some shallow water benthic foraminifera are able to retain functional chloroplasts (kleptoplasts) from their food source, i.e. diatoms. Here we assessed the functionality of the kleptoplast xanthophyll cycle (XC, i.e. the main diatom short-term photo-regulation mechanism) and we surveyed Haynesina germanica kleptoplast pigment composition over time and at different light regimes. Six common diatom lipophilic pigments were detected, two chlorophylls (Chl a, Chl c) and four carotenoids (fucoxanthin and by-products, diadinoxanthin, diatoxanthin and β-carotene), the same pigment profile as the diatom species frequently isolated at the sampling site...
2017: PloS One
https://www.readbyqxmd.com/read/28231085/extraction-identification-and-photo-physical-characterization-of-persimmon-diospyros-kaki-l-carotenoids
#3
Khalil Zaghdoudi, Orleans Ngomo, Régis Vanderesse, Philippe Arnoux, Bauyrzhan Myrzakhmetov, Céline Frochot, Yann Guiavarc'h
Carotenoid pigments were extracted and purified from persimmon fruits using accelerated solvent extraction (ASE). Eleven pigments were isolated and five of them were clearly identified as all-trans-violaxanthine, all-trans-lutein, all-trans-zeaxanthin all-trans-cryptoxanthin and all-trans-β-carotene. Absorption and fluorescence spectra were recorded. To evaluate the potential of ¹O₂ quenching of the purified carotenoids, we used a monocarboxylic porphyrin (P1COOH) as the photosensitizer to produce ¹O₂...
January 12, 2017: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28230973/unique-opto-electronic-structure-and-photo-reduction-properties-of-sulfur-doped-lead-chromates-explaining-their-instability-in-paintings
#4
Vanousheh Rahemi, Nasrin Sarmadian, Willemien Anaf, Koen Janssens, Dirk Lamoen, Bart Partoens, Karolien De Wael
Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artist's material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods...
February 23, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28230358/membrane-independence-of-ultrafast-photochemistry-in-pharaonis-halorhodopsin-testing-the-role-of-bacterioruberin
#5
Itay Gdor, Maya Mani-Hazan, Noga Friedman, Mordechai Sheves, Sanford Ruhman
Ultrafast photochemistry of p-HR in the intact Natronomonas pharaonic membrane has been studied by photoselective femtosecond pump-hyperspectral probe spectroscopy with high time resolution. Two variants of this sample, one with wild type retinal prosthetic groups, and another after shifting retinal absorption deep into the blue by reducing the Schiff base linkage were studied, and compared with previous results on detergent solubilized p-HR. This comparison shows that retinal photo-isomerization dynamics are identical in the membrane and in the solubilized sample...
February 23, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28230215/graphene-modulated-photo-absorption-in-adsorbed-azobenzene-monolayers
#6
Qiang Fu, Caterina Cocchi, Dmitrii Nabok, Andris Gulans, Claudia Draxl
The impact of graphene on the photo-absorption properties of trans- and cis-azobenzene monolayers is studied in the framework of density-functional theory and many-body perturbation theory. We find that, despite the weak hybridization between the electronic bands of graphene and those of the azobenzene monolayers, graphene remarkably modulates the absorption spectra of the adsorbates. The excitation energies are affected via two counteracting mechanisms: substrate polarization reduces the band-gap of azobenzene, and enhanced dielectric screening weakens the attractive interaction between electrons and holes...
February 22, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28229957/origins-and-mechanisms-of-hysteresis-in-organometal-halide-perovskites
#7
Cheng Li, Antonio Guerrero, Yu Zhong, Sven Huettner
Inorganic-organic organometal halide perovskites, such as CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> or CsPbI<sub>3</sub>, etc., are an unprecedented rising star in the field of photovoltaics since 2009, owing to its exceptionally high power conversion efficiency (PCE) and simple fabrication processability. Despite its relatively short history of development, intensive investigations have been concentrating on this material, ranging from crystal structure analysis and photophysical characterization, to performance optimization and device integration, etc...
February 23, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28229211/multicenter-international-experience-of-532%C3%A2-nm-laser-photo-vaporization-with-greenlight-xps-in-men-with-large-prostates-prostate-volume%C3%A2-%C3%A2-100%C3%A2-cc
#8
Malek Meskawi, Pierre-Alain Hueber, Roger Valdivieso, Franck Bruyere, Vincent Misrai, Georges Fournier, Ravi Munver, Ganesh Sivarajan, Matthew Rutman, Alexis E Te, Bilal Chughtai, Dean Elterman, Tristan Martel, Mounsif Azizi, Pierre I Karakiewicz, Kevin C Zorn
PURPOSE: To evaluate the outcomes and durability of photoselective vaporization of the prostate (PVP) using the XPS-180 system in patients with a large prostate volume (PV) > 100 cc at 4 years of follow-up in a large, multicenter experience. METHODS: 438 men with pre-operative transrectal ultrasound (TRUS) PV > 100 cc were treated in eight experienced centers in Canada, USA, and in France with the Greenlight XPS laser using PVP for the treatment of symptomatic BPH...
February 22, 2017: World Journal of Urology
https://www.readbyqxmd.com/read/28227995/comparison-of-pulse-wave-velocity-derived-from-accelerometer-and-reflective-photo-plethysmography-signals-placed-at-the-carotid-and-femoral-artery
#9
Jens Muehlsteff, Erik Bresch, Lars Schmitt, Jos Gelissen, Peter Bingley, Jens Muehlsteff, Erik Bresch, Lars Schmitt, Jos Gelissen, Peter Bingley, Jos Gelissen, Peter Bingley, Lars Schmitt, Jens Muehlsteff, Erik Bresch
Carotid - femoral pulse wave velocity is an established measure to assess cardiovascular risk and an interesting surrogate parameter towards non-invasive continuous blood pressure inference. Due to progress in sensing technologies for wearable wrist worn sensors, there are low cost sensor combinations of photo-plethysmography and high fidelity accelerometers available offering access to pulse information from larger arteries complemented by blood volume changes in the superficial tissue. In this work we compare pulse wave velocities derived from accelerometer and reflective photo-plethysmography signals placed at the carotid and femoral artery...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227363/3d-gabor-wavelet-based-vessel-filtering-of-photoacoustic-images
#10
Israr Ul Haq, Ryo Nagoaka, Takahiro Makino, Takuya Tabata, Yoshifumi Saijo, Israr Ul Haq, Ryo Nagoaka, Takahiro Makino, Takuya Tabata, Yoshifumi Saijo, Ryo Nagoaka, Yoshifumi Saijo, Takahiro Makino, Takuya Tabata
Filtering and segmentation of vasculature is an important issue in medical imaging. The visualization of vasculature is crucial for the early diagnosis and therapy in numerous medical applications. This paper investigates the use of Gabor wavelet to enhance the effect of vasculature while eliminating the noise due to size, sensitivity and aperture of the detector in 3D Optical Resolution Photoacoustic Microscopy (OR-PAM). A detailed multi-scale analysis of wavelet filtering and Hessian based method is analyzed for extracting vessels of different sizes since the blood vessels usually vary with in a range of radii...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227149/automated-and-reconfigurable-platform-for-niosome-generation-based-on-a-microfluidic-architecture
#11
Frederic Tessier, Myriam Laprise-Pelletier, Eric Boilard, Marc-Andre Fortin, Amine Miled, Frederic Tessier, Myriam Laprise-Pelletier, Eric Boilard, Marc-Andre Fortin, Amine Miled, Marc-Andre Fortin, Eric Boilard, Amine Miled, Frederic Tessier, Myriam Laprise-Pelletier
Drug delivery at the nano-scale is becoming an important topic in nano and regenerative medicine as it can offer a very localized therapy. Therefore, niosomes are one of the most important vehicles to release drug at the nanoscale. In this paper, we present a new automated microsystem for niosome generation on-demand. Used niosome were based on a mixture of cholesterol and dicetyl phosphate with chloroform. Three compact micropumps are connected to a microfluidic substrate in order to generate 100 nm noisome vesicles...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227148/towards-a-multi-wavelength-spectroscopy-platform-for-blood-characterization-and-analysis
#12
Alireza Avakh Kisomi, Hamza Landari, Mounir Boukadoum, Amine Miled, Benoit Gosselin, Alireza Avakh Kisomi, Hamza Landari, Mounir Boukadoum, Amine Miled, Benoit Gosselin, Hamza Landari, Benoit Gosselin, Amine Miled, Mounir Boukadoum
Passing multiple light wavelengths through a blood sample makes it possible to investigate the presence and composition of cells, metabolytes and analytes such as blood cells, glucose, lactate and oxygen, providing valuable indications for diagnostic and health monitoring. In this paper, we present a test prototype of a multi-wavelength blood spectroscopy platform integrated with a microfluidic substrate to collect and convey blood samples through a series of micro-LEDs and a photo-detector. This spectroscopy platform is a proof of concept for a system that can collect absorbance and transmittance parameters of blood samples at several wavelengths within the visible and NIR spectrum, and transmit them wirelessly to a base station for real-time calculation and analysis...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226914/sticker-type-ecg-ppg-concurrent-monitoring-system-hybrid-integration-of-cmos-soc-and-organic-sensor-device
#13
Yongsu Lee, Hyeonwoo Lee, Seunghyup Yoo, Hoi-Jun Yoo, Yongsu Lee, Hyeonwoo Lee, Seunghyup Yoo, Hoi-Jun Yoo, Seunghyup Yoo, Yongsu Lee, Hoi-Jun Yoo, Hyeonwoo Lee
The sticker-type sensor system is proposed targeting ECG/PPG concurrent monitoring for cardiovascular diseases. The stickers are composed of two types: Hub and Sensor-node (SN) sticker. Low-power CMOS SoC for measuring ECG and PPG signal is hybrid integrated with organic light emitting diodes (OLEDs) and organic photo detector (OPD). The sticker has only 2g weight and only consumes 141μW. The optical calibration loop is adopted for maintaining SNR of PPG signal higher than 30dB. The pulse arrival time (PAT) and SpO2 value can be extracted from various body parts and verified comparing with the reference device from 20 people in-vivo experiments...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226871/identifying-depressed-patients-with-and-without-suicidal-ideation-by-finger-photo-plethysmography
#14
A H Khandoker, V Luthra, Y Abouallaban, S Saha, K I Ahmed, R Mostafa, N Chowdhury, H F Jelinek, A H Khandoker, V Luthra, Y Abouallaban, S Saha, K I Ahmed, R Mostafa, N Chowdhury, H F Jelinek, A H Khandoker, R Mostafa, H F Jelinek, N Chowdhury, Y Abouallaban, S Saha, K I Ahmed, V Luthra
Major Depressive Disorder (MDD) is a serious mental disorder that if untreated not only affects physical health but also has a high risk of suicide. While the neurophysiological phenomena that contribute to the formation of Suicidal Ideation (SI) are still ill-defined, clear links between MDD and cardiovascular disease have been reported. The aim of this study is to extract suitable features from arterial pulse signals with a view to predicting SI within MDD and control groups. Sixteen unmedicated MDD patients with a history of SI (MDDSI+), sixteen without SI (MDDSI-) and twenty-nine healthy subjects (CONT) were recruited at a psychiatric clinic in the UAE...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226588/robust-estimation-of-respiratory-rate-via-ecg-and-ppg-derived-respiratory-quality-indices
#15
Drew A Birrenkott, Marco A F Pimentel, Peter J Watkinson, David A Clifton, Drew A Birrenkott, Marco A F Pimentel, Peter J Watkinson, David A Clifton, Peter J Watkinson, Marco A F Pimentel, Drew A Birrenkott, David A Clifton
Respiratory rate (RR) is one of the most informative indicators of a patient's health status. However, automated, non-invasive measurements of RR are insufficiently robust for use in clinical practice. A number of methods have been described in the literature to estimate RR from both photo-plethysmography (PPG) and electrocardiography (ECG) based on three physiological modulations of respiration: amplitude modulation (AM), frequency modulation (FM), and baseline wander (BW). However, the quality of the respiratory information acquired is highly patient-dependent and often too noisy to be used...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28225610/intramolecular-energy-and-electron-transfer-within-a-diazaperopyrenium-based-cyclophane
#16
Xirui Gong, Ryan M Young, Karel J Hartlieb, Claire Miller, Yilei Wu, Hai Xiao, Peng Li, Nema Hafezi, Jiawang Zhou, Lin Ma, Tao Cheng, William A Goddard, Omar K Farha, Joseph T Hupp, Michael R Wasielewski, J Fraser Stoddart
Molecules capable of performing highly efficient energy transfer and ultrafast photo-induced electron transfer in well-defined multichromophoric structures are indispensable to the development of artificial photosynthetic systems. Herein, we report on the synthesis, characterization and photophysical properties of a rationally designed multichromophoric tetracationic cyclophane, DAPPBox(4+), containing a diazaperopyrenium (DAPP(2+)) unit and an extended viologen (ExBIPY(2+)) unit, which are linked together by two p-xylylene bridges...
February 22, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28225115/solvothermal-assisted-synthesis-of-self-assembling-tio2-nanorods-on-large-graphitic-carbon-nitride-sheets-with-their-anti-recombination-in-the-photocatalytic-removal-of-cr-vi-and-rhodamine-b-under-visible-light-irradiation
#17
Dingze Lu, Pengfei Fang, Wenhui Wu, Junqian Ding, Lulu Jiang, Xiaona Zhao, Chunhe Li, Minchen Yang, Yuanzhi Li, Dahai Wang
TiO2-based nanorods (TNRs) were self-assembled on large graphitic carbon nitride (g-C3N4) sheets via the solvothermal-assisted route. The results demonstrated that the effective anchoring of TNRs (a side length of ca. 200-300 nm) was highly dispersed on the surface of whole g-C3N4 sheets. The shift in the Ti 2p XPS core level spectrum indicated an increase in the net positive charge of the Ti ions, ensuring the formation of an interface between TNRs and g-C3N4. The charge transferred from g-C3N4 sheets to TNRs effectively prevented the recombination of excited charges, which is consistent with the significant quenching of PL...
February 22, 2017: Nanoscale
https://www.readbyqxmd.com/read/28224986/mass-spectrometric-monitoring-of-interfacial-photoelectron-transfer-and-imaging-of-active-crystalline-facets-of-semiconductors
#18
Hongying Zhong, Juan Zhang, Xuemei Tang, Wenyang Zhang, Ruowei Jiang, Rui Li, Disong Chen, Peng Wang, Zhiwei Yuan
Monitoring of interfacial electron transfer (ET) in situ is important to understand the ET mechanism and designing efficient photocatalysts. We describe herein a mass spectrometric approach to investigate the ultrafast transfer of photoelectrons that are generated by ultraviolet irradiation on surfaces of semiconductor nanoparticles or crystalline facets. The mass spectrometric approach can not only untargetedly detect various intermediates but also monitor their reactivity through associative or dissociative photoelectron capture dissociation, as well as electron detachment dissociation of adsorbed molecules...
February 22, 2017: Nature Communications
https://www.readbyqxmd.com/read/28224900/chemical-oxygen-demand-historical-perspectives-and-future-challenges
#19
REVIEW
René Bernard Geerdink, Ricardo Sebastiaan van den Hurk, Onno Jacob Epema
Determining the chemical oxygen demand (COD) is challenging because of the chemicals that are used in the current methods. There is an urgent need to determine the pollution in surface waters from (heavy) industry via a simple, reliable and fast method. However, the current procedures use hazardous chemicals, such as mercury, to suppress chloride interferences. This challenge has not been resolved. The introduction of modern detection techniques, such as chemiluminescence and oxidation procedures, e.g., microwave and ultrasound dissolution, has not resulted in a breakthrough...
April 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28224892/construction-and-in-vitro-evaluation-of-enzyme-nanoreactors-based-on-carboxymethyl-chitosan-for-arginine-deprivation-in-cancer-therapy
#20
Tian Zeng, Yi Zhang, Qiongjiao Yan, Zhijun Huang, Ling Zhang, Xiaozhe Yi, Junrong Chen, Guanghua He, Yihua Yin
In this study, a pH-induced morphological transition from micelles to vesicles for an amphiphilic photo cross-linkable biocopolymer (Az-NaCMCS), synthesized by mixing azidobenzaldehyde (Az) and an aqueous solution of carboxymethyl chitosan sodium salt (NaCMCS), was used for encapsulation of l-arginine deiminase (ADI). The aqueous solution of enzyme-loaded vesicles obtained was followed by UV-irradiation to result in shell cross-linked enzyme nanoreactors. The nanoreactors were characterized by TEM and DLS. Its encapsulation efficiency and loading capacity were determined...
April 15, 2017: Carbohydrate Polymers
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