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https://www.readbyqxmd.com/read/28351016/nano-enabled-paper-humidity-sensor-for-mobile-based-point-of-care-lung-function-monitoring
#1
Mitradip Bhattacharjee, Harshal B Nemade, Dipankar Bandyopadhyay
The frequency of breathing and peak flow rate of exhaled air are necessary parameters to detect chronic obstructive pulmonary diseases (COPDs) such as asthma, bronchitis, or pneumonia. We developed a lung function monitoring point-of-care-testing device (LFM-POCT) consisting of mouthpiece, paper-based humidity sensor, micro-heater, and real-time monitoring unit. Fabrication of a mouthpiece of optimal length ensured that the exhaled air was focused on the humidity-sensor. The resistive relative humidity sensor was developed using a filter paper coated with nanoparticles, which could easily follow the frequency and peak flow rate of the human breathing...
March 22, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28350953/degradation-of-hole-transport-materials-via-exciton-driven-cyclization
#2
Bruce M Bell, Michael B Clark, David D Devore, Timothy S De Vries, Robert D J Froese, Kaitlyn C Gray, David H K Jackson, Thomas F Kuech, Hong-Yeop Na, Kenneth L Kearns, Kyung Joo Lee, Sukrit Mukhopadhyay, Aaron A Rachford, Liam Patrick Spencer, William Henry Hunter Woodward
Organic light emitting diode (OLED) displays have been an active and intense area of research for well over a decade and have now reached commercial success for displays from cell phones to large format televisions. A more thorough understanding of the many different potential degradation modes which cause OLED device failure will be necessary to develop the next generation of OLED materials, improve device lifetime, and to ultimately improve the cost vs. performance ratio. Each of the different organic layers in an OLED device can be susceptible to unique decomposition pathways, however stability towards excitons is critical for emissive layer (EML) materials as well as any layer near the recombination zone...
March 28, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28346338/smartfluo-a-method-and-affordable-adapter-to-measure-chlorophyll-a-fluorescence-with-smartphones
#3
Anna Friedrichs, Julia Anke Busch, Hendrik Jan van der Woerd, Oliver Zielinski
In order to increase the monitoring capabilities of inland and coastal waters, there is a need for new, affordable, sensitive and mobile instruments that could be operated semi-automatically in the field. This paper presents a prototype device to measure chlorophyll a fluorescence: the SmartFluo. The device is a combination of a smartphone offering an intuitive operation interface and an adapter implying a cuvette holder, as well as a suitable illumination source. SmartFluo is based on stimulated fluorescence of water constituents such as chlorophyll a...
March 25, 2017: Sensors
https://www.readbyqxmd.com/read/28345508/use-of-a-novel-portable-led-based-capillary-refill-time-simulator-within-a-disaster-triage-context
#4
Todd P Chang, Genevieve Santillanes, Ilene Claudius, Phung K Pham, James Koved, John Cheyne, Marianne Gausche-Hill, Amy H Kaji, Saranya Srinivasan, J Joelle Donofrio, Cynthia Bir
Introduction A simple, portable capillary refill time (CRT) simulator is not commercially available. This device would be useful in mass-casualty simulations with multiple volunteers or mannequins depicting a variety of clinical findings and CRTs. The objective of this study was to develop and evaluate a prototype CRT simulator in a disaster simulation context. METHODS: A CRT prototype simulator was developed by embedding a pressure-sensitive piezo crystal, and a single red light-emitting diode (LED) light was embedded, within a flesh-toned resin...
March 27, 2017: Prehospital and Disaster Medicine
https://www.readbyqxmd.com/read/28345084/the-importance-of-solvent-quality-on-the-modification-of-conjugated-polymer-conformation-and-thermodynamics-with-illumination
#5
Brian Morgan, Mark D Dadmun
Device efficiency in key organic electronic devices such as organic photovoltaics, field transistors, and light emitting diodes has long been known to be closely tied to the conformation of the conjugated polymer chains which make up the active layers. Our previous results show that light exposure can have a profound effect on the structure and assembly of these optoelectronic materials in solution. In order to advance our understanding of the role which solvent quality plays in this phenomenon, we have further studied the modulation of these illumination dependent structural changes on the key benchmark conjugated polymers P3HT and MEH-PPV as a function of solvent quality over a wide range of polymer solubilities...
March 27, 2017: Soft Matter
https://www.readbyqxmd.com/read/28342007/the-effect-of-led-on-blood-microcirculation-during-chronic-wound-healing-in-diabetic-and-non-diabetic-patients-a-prospective-double-blind-randomized-study
#6
Igor Frangez, Ksenija Cankar, Helena Ban Frangez, Dragica Maja Smrke
Chronic wounds, especially in diabetic patients, represent a challenging health issue. Since standard treatment protocols often do not provide satisfactory results, additional treatment methods-like phototherapy using low-level light therapy-are being investigated. The aim of our study was to evaluate the effect of phototherapy with light-emitting diodes on chronic wound treatment in diabetic and non-diabetic patients. Since a sufficient blood supply is mandatory for wound healing, the evaluation of microcirculation in the healthy skin at a wound's edge was the main outcome measure...
March 25, 2017: Lasers in Medical Science
https://www.readbyqxmd.com/read/28340762/reference-free-spectroscopic-determination-of-fat-and-protein-in-milk-in-the-visible-and-near-infrared-region-below-1000nm-using-spatially-resolved-diffuse-reflectance-fiber-probe
#7
Andrey Bogomolov, Valeria Belikova, Vladislav Galyanin, Anastasiia Melenteva, Hans Meyer
New technique of diffuse reflectance spectroscopic analysis of milk fat and total protein content in the visible (Vis) and adjacent near infrared (NIR) region (400-995nm) has been developed and tested. Sample analysis was performed through a probe having eight 200-µm fiber channels forming a linear array. One of the end fibers was used for the illumination and other seven - for the spectroscopic detection of diffusely reflected light. One of the detection channels was used as a reference to normalize the spectra and to convert them into absorbance-equivalent units...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340752/highly-sensitive-ratiometric-quantification-of-cyanide-in-water-with-gold-nanoparticles-via-resonance-rayleigh-scattering
#8
Yulán Hernández, Yves Coello, Raluca M Fratila, Jesús M de la Fuente, Troy A Lionberger
A highly sensitive and selective ratiometric sensor for the quantification of cyanide (CN(-)) in aqueous samples has been developed using spherical gold nanoparticles (AuNPs) stabilized by polysorbate 40 (PS-40). Three different AuNP sizes (14, 40 and 80nm mean diameters) were used to evaluate the response of the sensor using both colorimetric and Resonance Rayleigh Scattering (RRS) detection schemes. The best results were obtained for the sensor using 40nm AuNPs, for which the limits of detection (LODs) were found to be 100nmolL(-1) in a benchtop instrument and 500nmolL(-1) by the naked eye, values well below the maximum acceptable level for drinking water (1...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28339753/in-ovo-monochromatic-green-light-photostimulation-enhances-embryonic-somatotropic-axis-activity
#9
L Dishon, N Avital-Cohen, D Malamud, R Heiblum, S Druyan, T E Porter, M Gumulka, I Rozenboim
Previous studies demonstrated that in ovo photostimulation with monochromatic green light increases body weight and accelerates muscle development in broilers. The mechanism in which in ovo photostimulation accelerates growth and muscle development is not clearly understood. The objective of the current study was to define development of the somatotropic axis in the broiler embryo associated with in ovo green light photostimulation. Two-hundred-forty fertile broiler eggs were divided into 2 groups. The first group was incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0...
February 23, 2017: Poultry Science
https://www.readbyqxmd.com/read/28332818/in-situ-preparation-of-metal-halide-perovskite-nanocrystal-thin-films-for-improved-light-emitting-devices
#10
Lianfeng Zhao, Yao-Wen Yeh, Nhu L Tran, Fan Wu, Zhengguo Xiao, Ross A Kerner, YunHui L Lin, Gregory D Scholes, Nan Yao, Barry P Rand
Hybrid organic-inorganic halide perovskite semiconductors are attractive candidates for optoelectronic applications, such as photovoltaics, light-emitting diodes, and lasers. Perovskite nanocrystals are of particular interest, where electrons and holes can be confined spatially, promoting radiative recombination. However, nanocrystalline films based on traditional colloidal nanocrystal synthesis strategies suffer from the use of long insulating ligands, low colloidal nanocrystal concentration, and significant aggregation during film formation...
March 23, 2017: ACS Nano
https://www.readbyqxmd.com/read/28332395/electrolyte-gated-red-green-and-blue-organic-light-emitting-diodes
#11
Jiang Liu, Dustin Yuan Chen, Xinning Luan, Kwing Tong, Fangchao Zhao, Chao Liu, Qibing Pei, Huaping Li
We report vertical, electrolyte-gated, red, green and blue phosphorescent small molecule organic light emitting diodes (OLED), in which light emission was modified by tuning the electron injection via electrochemical doping of the electron injection layer 4,4-bis(N-carbazolyl)-1,1-biphenyl (CBP) under the assistance of a polymer electrolyte. These devices comprise an electrolyte capacitor on top of a conventional OLED, with the interfacial contact between the electrolyte and electron injection layer CBP of OLEDs achieved through a porous cathode...
March 23, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28331281/the-involvement-of-atf4-and-s-opsin-in-retinal-photoreceptor-cell-damage-induced-by-blue-led-light
#12
Emi Ooe, Kazuhiro Tsuruma, Yoshiki Kuse, Saori Kobayashi, Masamitsu Shimazawa, Hideaki Hara
PURPOSE: Blue light is a high-energy emitting light with a short wavelength in the visible light spectrum. Blue light induces photoreceptor apoptosis and causes age-related macular degeneration or retinitis pigmentosa. In the present study, we investigated the roles of endoplasmic reticulum (ER) stress induced by blue light-emitting diode (LED) light exposure in murine photoreceptor cells. METHODS: The murine photoreceptor cell line was incubated and exposed to blue LED light (464 nm blue LED light, 450 lx, 3 to 24 h)...
2017: Molecular Vision
https://www.readbyqxmd.com/read/28328316/a-high-throughput-screening-assay-using-a-photoconvertable-protein-for-identifying-inhibitors-of-transcription-translation-or-proteasomal-degradation
#13
David K Heidary, Ashley Fox, Chris I Richards, Edith C Glazer
Dysregulated transcription, translation, and protein degradation are common features of cancer cells, regardless of specific genetic profiles. Several clinical anticancer agents take advantage of this characteristic vulnerability and interfere with the processes of transcription and translation or inhibit protein degradation. However, traditional assays that follow the process of protein production and removal require multistep processing and are not easily amenable to high-throughput screening. The use of recombinant fluorescent proteins provides a convenient solution to this problem, and moreover, photoconvertable fluorescent proteins allow for ratiometric detection of both new protein production and removal of existing proteins...
April 2017: SLAS Discov
https://www.readbyqxmd.com/read/28326023/infrared-video-pupillography-coupled-with-smart-phone-led-for-measurement-of-pupillary-light-reflex
#14
Lily Yu-Li Chang, Jason Turuwhenua, Tian Yuan Qu, Joanna M Black, Monica L Acosta
Clinical assessment of pupil appearance and pupillary light reflex (PLR) may inform us the integrity of the autonomic nervous system (ANS). Current clinical pupil assessment is limited to qualitative examination, and relies on clinical judgment. Infrared (IR) video pupillography combined with image processing software offer the possibility of recording quantitative parameters. In this study we describe an IR video pupillography set-up intended for human and animal testing. As part of the validation, resting pupil diameter was measured in human subjects using the NeurOptics(™) (Irvine, CA, USA) pupillometer, to compare against that measured by our IR video pupillography set-up, and PLR was assessed in guinea pigs...
2017: Frontiers in Integrative Neuroscience
https://www.readbyqxmd.com/read/28325941/blue-organic-light-emitting-diodes-realizing-external-quantum-efficiency-over-25-using-thermally-activated-delayed-fluorescence-emitters
#15
Takuya Miwa, Shosei Kubo, Katsuyuki Shizu, Takeshi Komino, Chihaya Adachi, Hironori Kaji
Improving the performance of blue organic light-emitting diodes (OLEDs) is needed for full-colour flat-panel displays and solid-state lighting sources. The use of thermally activated delayed fluorescence (TADF) is a promising approach to efficient blue electroluminescence. However, the difficulty of developing efficient blue TADF emitters lies in finding a molecular structure that simultaneously incorporates (i) a small energy difference between the lowest excited singlet state (S1) and the lowest triplet state (T1), ΔE ST, (ii) a large oscillator strength, f, between S1 and the ground state (S0), and (iii) S1 energy sufficiently high for blue emission...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28324762/chrysanthemum-morphology-photosynthetic-efficiency-and-antioxidant-capacity-are-differentially-modified-by-light-quality
#16
Liang Zheng, Marie-Christine Van Labeke
The effect of light quality on leaf morphology, photosynthetic efficiency and antioxidant capacity of leaves that fully developed under a specific spectrum was investigated in Chrysanthemum cv. Four light treatments were applied at 100μmolm(-2)s(-1) and a photoperiod of 14h using light-emitting diodes, which were 100% red (R), 100% blue (B), 75% red with 25% blue (RB) and white (W), respectively. Intraspecific variation was investigated by studying the response of eight cultivars. Overall, red light significantly decreased the leaf area while the thinnest leaves were observed for W...
March 11, 2017: Journal of Plant Physiology
https://www.readbyqxmd.com/read/28324593/phosphorescent-neutral-iridium-iii-complexes-for-organic-light-emitting-diodes
#17
REVIEW
Abd Rashid Bin Mohd Yusoff, Aron J Huckaba, Mohammad Khaja Nazeeruddin
The development of transition metal complexes for application in light-emitting devices is currently attracting significant research interest. Among phosphorescent emitters, those involving iridium (III) complexes have proven to be exceedingly useful due to their relatively short triplet lifetime and high phosphorescence quantum yields. The emission wavelength of iridium (III) complexes significantly depends on the ligands, and changing the electronic nature and the position of the ligand substituents can control the properties of the ligands...
April 2017: Topics in Current Chemistry (Journal)
https://www.readbyqxmd.com/read/28322286/investigation-on-the-corrosive-effect-of-nh3-during-ingan-gan-multi-quantum-well-growth-in-light-emitting-diodes
#18
J Yang, D G Zhao, D S Jiang, P Chen, J J Zhu, Z S Liu, W Liu, X Li, F Liang, S T Liu, L Q Zhang, H Yang
Three series of samples with different NH3 flow rate are grown and the optical and structural properties are investigated. It is found that apart from a positive effect on keeping a high partial pressure of nitrogen to enhance indium incorporation, NH3 may also play a negative effect on indium incorporation during InGaN growth. Especially, when temperature is relatively high, the hydrogen generated from the dissociation of NH3 may suppress the chemical reaction which produces InN, leading to a reduced indium incorporation efficiency during the InGaN layer growth...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28322055/a-statistical-paradigm-for-organic-optoelectronic-devices-normal-force-testing-for-adhesion-of-opvs-and-oleds
#19
Lindsay Vasilak, Silvie M Tanu Halim, Hrishikesh Das Gupta, Juan Yang, Marleen Kamperman, Ayse Turak
In this study, we assess the utility of a normal force (pull-test) approach to measuring adhesion in organic solar cells and organic light emitting diodes. This approach is a simple and practical method of monitoring the impact of systematic changes in materials, processing conditions, or environmental exposure on interfacial strength and electrode delamination. The ease of measurement enables a statistical description with numerous samples, variant geometry, and minimal preparation. After examining over 70 samples, using the Weibull modulus and the characteristic breaking strength as metrics, we were able to successfully differentiate the adhesion values between Alq3 and P3HT:PCBM interfaces with Al, and between two annealing times for the bulk heterojunction polymer blends...
March 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28321394/computational-studies-on-optoelectronic-and-nonlinear-properties-of-octaphyrin-derivatives
#20
Nasarul Islam, Irfan H Lone
The electronic and nonlinear optical (NLO) properties of octaphyrin derivatives were studied by employing the DFT/TDFT at CAM-B3LYP/6-311++G (2d, 2p) level of the theory. Thiophene, phenyl, methyl and cyano moieties were substituted on the molecular framework of octaphyrin core, in order to observe the change in optoelectronic and nonlinear response of these systems. The frontier molecular orbital studies and values of electron affinity reveals that the studied compounds are stable against the oxygen and moisture present in air...
2017: Frontiers in Chemistry
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