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https://www.readbyqxmd.com/read/29149727/surface-modification-of-electrospun-poly-l-lactic-acid-scaffolds-by-reactive-magnetron-sputtering
#1
E N Bolbasov, P V Maryin, K S Stankevich, A I Kozelskaya, E V Shesterikov, Yu I Khodyrevskaya, M V Nasonova, D K Shishkova, Yu A Kudryavtseva, Y G Anissimov, S I Tverdokhlebov
In this study, we modified the surface of bioresorbable electrospun poly-(l-lactic) acid (PLLA) scaffolds by reactive magnetron sputtering of a titanium target under a nitrogen atmosphere. We examined the influence of the plasma treatment time on the structure and properties of electrospun PLLA scaffolds using SEM, XRF, FTIR, XRD, optical goniometry, and mechanical testing. It was observed that the coating formed did not change physicomechanical properties of electrospun PLLA scaffolds and simultaneously, increased their hydrophilicity...
November 12, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/29149722/effects-of-middle-ear-quasi-static-stiffness-on-sound-transmission-quantified-by-a-novel-3-axis-optical-force-sensor
#2
Ivo Dobrev, Jae Hoon Sim, Baktash Aqtashi, Alexander M Huber, Thomas Linder, Christof Röösli
BACKGROUND: Intra-operative quantification of the ossicle mobility could provide valuable feedback for the current status of the patient's conductive hearing. However, current methods for evaluation of middle ear mobility are mostly limited to the surgeon's subjective impression through manual palpation of the ossicles. This study investigates how middle ear transfer function is affected by stapes quasi-static stiffness of the ossicular chain. The stiffness of the middle ear is induced by a) using a novel fiber-optic 3-axis force sensor to quantify the quasi-static stiffness of the middle ear, and b) by artificial reduction of stapes mobility due to drying of the middle ear...
November 10, 2017: Hearing Research
https://www.readbyqxmd.com/read/29149695/rheo-optical-near-infrared-nir-spectroscopy-study-of-partially-miscible-polymer-blend-of-polymethyl-methacrylate-pmma-and-polyethylene-glycol-peg
#3
Hideyuki Shinzawa, Junji Mizukado
Tensile deformations of a partially miscible blend of polymethyl methacrylate (PMMA) and polyethylene glycol (PEG) is studied by a rheo-optical characterization near-infrared (NIR) technique to probe deformation behavior during tensile deformation. Sets of NIR spectra of the polymer samples were collected by using an acousto-optic tunable filter (AOTF) NIR spectrometer coupled with a tensile testing machine as an excitation device. While deformations of the samples were readily captured as strain-dependent NIR spectra, the entire feature of the spectra was overwhelmed with the baseline fluctuation induced by the decrease in the sample thickness and subsequent change in the light scattering...
November 11, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/29149571/imaging-and-spectroscopy-of-single-metal-nanostructure-absorption
#4
Anneli Joplin, Wei-Shun Chang, Stephan Link
The highly tunable optical properties of metal nanoparticles make them an ideal building block in any application that requires control over light, heat, or electrons on the nanoscale. Because of their size, metal nanoparticles both absorb and scatter light efficiently. Consequently, improving their performance often involves shifting the balance between absorption and scattering to promote desirable features of their optical properties. Scattering by single metal nanoparticles is commonly characterized using dark-field scattering spectroscopy, but routine methods to characterize pure absorption over a broad wavelength range are much more complex...
November 17, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29149546/the-photophysical-and-photoacoustic-properties-of-quadrupolar-borondifluoride-curcuminoid-dyes
#5
Stephanie Bellinger, Maryam Hatamimoslehabadi, Seema Bag, Farha Mithila, Jeffrey La, Mathieu Frennete, Samir Laoui, David Szalda, Chandra Yelleswarapu, Jonathan Rochford
The synthesis and characterization of a series of donor-π-acceptor-π-donor (D-A-D) curcuminoid molecules are here presented incorporating π-extended aryl and electron-donating amino terminal functionalization. Computational evaluation shows these molecules possess quadrupolar character with the lowest energy transitions displaying high molar extinction coefficients with broad tunability through manipulation of terminal donating groups. Consistent with their quadrupolar nature, these molecules show varying degrees of solvatochromic behavior in both their absorption and emission spectra which has been analyzed by Lippert-Mataga and Kamlet-Taft analysis...
November 17, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29149542/spectrally-encoded-coherence-tomography-and-reflectometry-sectr-simultaneous-en-face-and-cross-sectional-imaging-at-2-gigapixels-per-second
#6
Mohamed T El-Haddad, Ivan Bozic, Yuankai K Tao
Non-invasive biological imaging is crucial for understanding in vivo structure and function. Optical coherence tomography (OCT) and reflectance confocal microscopy are two of the most widely used optical modalities for exogenous contrast-free high-resolution three-dimensional imaging in non-fluorescent scattering tissues. However, sample motion remains a critical barrier to raster-scanned acquisition and reconstruction of wide-field anatomically accurate volumetric datasets. We introduce spectrally encoded coherence tomography and reflectometry (SECTR), a high-speed multimodality system for simultaneous OCT and spectrally-encoded reflectance (SER) imaging...
November 17, 2017: Journal of Biophotonics
https://www.readbyqxmd.com/read/29149540/controllable-synthesis-of-organic-microcrystals-with-tunable-emission-color-and-morphology-based-on-molecular-packing-mode
#7
Zhi-Zhou Li, Liang-Sheng Liao, Xue-Dong Wang
Organic microcrystals are of essential importance for high fluorescence efficiency, ordered molecular packing mode, minimized defects, and smooth shapes, which are extensively applied in organic optoelectronics. The molecular packing mode significantly influences the optical/electrical properties of organic microcrystals, which makes the controllable preparation of organic microcrystals with desired molecular packing mode extremely important. In the study, yellow-emissive α phase organic microcrystals with rectangular morphology and green-emissive β phase perylene microcrystals with rhombic morphology are separately prepared by simply controlling the solution concentration...
November 17, 2017: Small
https://www.readbyqxmd.com/read/29149423/structural-and-visible-near%C3%A2-infrared-optical-properties-of-cr-doped-tio2-for-colored-cool-pigments
#8
Le Yuan, Xiaolong Weng, Ming Zhou, Qingyong Zhang, Longjiang Deng
Chromium-doped TiO2 pigments were synthesized via a solid-state reaction method and studied with X-ray diffraction, SEM, XPS, and UV-VIS-NIR reflectance spectroscopy. The incorporation of Cr(3+) accelerates the transition from the anatase phase to the rutile phase and compresses the crystal lattice. Moreover, the particle morphology, energy gap, and reflectance spectrum of Cr-doped TiO2 pigments is affected by the crystal structure and doping concentration. For the rutile samples, some of the Cr(3+) ions are oxidized to Cr(4+) after sintering at a high temperature, which leads to a strong near-infrared absorption band due to the (3)A2 → (3) T1 electric dipole-allowed transitions of Cr(4+)...
November 17, 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/29149420/blood-clearance-and-occupational-exposure-for-177-lu-dotatate-compared-to-177-lu-psma-radionuclide-therapy
#9
Mohammad Abuqbeitah, Mustafa Demir, Lebriz Uslu-Beşli, Nami Yeyin, Kerim Sönmezoğlu
The main target of this work is to examine blood clearance and external exposure for (177)Lu-DOTATATE compared with new emerging (177)Lu-PSMA therapy. Blood clearance and radiation exposure of 31 patients treated with 5.5 ± 1.1 GBq (177)Lu-DOTATATE were compared to those of 23 patients treated with 7.4 GBq (177)Lu-PSMA. Dose rates were measured at several distances and time points up to 120 h after treatment. Blood samples were collected conjunctively after infusion. Caregiver's cumulative dose was measured by means of an OSL (optically stimulated luminescence) dosimeter for 4-5 days and medical staff's dose was also estimated using electronic personal dosimeters...
November 17, 2017: Radiation and Environmental Biophysics
https://www.readbyqxmd.com/read/29149320/organic-scintillator-for-real-time-neutron-dosimetry
#10
Kyle A Beyer, Angela Di Fulvio, Liliana Stolarczyk, Wiktor Parol, Natalia Mojzeszek, Renata Kopéc, Shaun D Clarke, Sara A Pozzi
We developed a radiation detector based on an organic scintillator for spectrometry and dosimetry of out-of-field secondary neutrons from clinical proton beams. The detector consists of an EJ-299-34 crystalline organic scintillator, coupled by fiber optic cable to a silicon photomultiplier (SiPM). Proof of concept measurements were taken with 137Cs and 252Cf, and corresponding simulations were performed in MCNPX-PoliMi. Despite its small size, the detector is able to discriminate between neutron and gamma-rays via pulse shape discrimination...
November 15, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/29149239/label-free-in-vivo-imaging-of-corneal-lymphatic-vessels-using-microscopic-optical-coherence-tomography
#11
Jens Horstmann, Hinnerk Schulz-Hildebrandt, Felix Bock, Sebastian Siebelmann, Eva Lankenau, Gereon Hüttmann, Philipp Steven, Claus Cursiefen
Purpose: Corneal neovascularization, in particular lymphangiogenesis, is a limiting factor in corneal transplant survival. Novel treatment approaches focus on (selective) inhibition and regression of lymphatic vessels. Imaging clinically invisible corneal lymphatic vessels is a prerequisite for these strategies. Using a murine model, this study investigates whether corneal lymphatic vessels can be imaged using microscopic optical coherence tomography (mOCT). Methods: Corneal neovascularization was induced by intrastromal placement of 11...
November 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/29149238/diabetic-neuroglial-changes-in-the-superficial-and-deep-nonperfused-areas-on-optical-coherence-tomography-angiography
#12
Yoko Dodo, Tomoaki Murakami, Kiyoshi Suzuma, Shin Yoshitake, Tatsuya Yoshitake, Kenji Ishihara, Masahiro Fujimoto, Yuko Miwa, Akitaka Tsujikawa
Purpose: To evaluate the relationship between lamellar capillary nonperfusion on optical coherence tomography angiography (OCTA) images and neuroglial changes on structural optical coherence tomography (OCT) images in diabetic retinopathy (DR). Methods: We retrospectively reviewed 101 consecutive eyes of 69 patients with DR. OCTA and OCT images within a 3 × 3-mm square centered on the fovea were acquired simultaneously. The nonperfused areas (NPAs) in the superficial capillary layer (sNPA) (from the nerve fiber layer [NFL] to the inner plexiform layer [IPL]), the deep layer (dNPA) (corresponding mainly to the inner nuclear layer [INL]), or both layers (bNPA) were measured individually along 10 transverse lines...
November 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/29149233/lighting-up-long-range-charge-transfer-states-by-a-localized-plasmonic-field
#13
Zhen Xie, Sai Duan, Chuan-Kui Wang, Yi Luo
The long-range charge-transfer states in a donor-acceptor system exhibit well separated electron-hole pairs, but are often difficult to achieve by optical means owing to a very small overlap between the wave functions of the donor and acceptor. We have found that the introduction of a spatially confined plasmon can enhance the transition probability to the long-range charge-transfer states as it can effectively break the intrinsic symmetry selection rule imposed on the system. Meanwhile, the intensity borrowed from local excitations could also be selectively promoted, allowing the manipulation of the excited quantum states...
November 17, 2017: Nanoscale
https://www.readbyqxmd.com/read/29149211/occupational-exposure-to-unburnt-tobacco-and-potential-risk-of-toxic-optic-neuropathy-a-cross-sectional-study-among-beedi-rollers-in-selected-rural-areas-of-coastal-karnataka-india
#14
Soujanya Kaup, Ansaba Naseer, Siddharudha Shivalli, Cynthia Arunachalam
BACKGROUND: Beedi also known as poor man's cigarette is manufactured in almost all major states of India. Beedi workers are exposed to various health risks. There is an increased risk of systemic absorption of tobacco through skin and mucous membrane. The optic nerve is susceptible to damage from several toxic substances including tobacco. This group of disorders is known as toxic optic neuropathy (TON). The association of TON with occupational exposure to unburnt tobacco in beedi rollers has not been explored...
2017: PloS One
https://www.readbyqxmd.com/read/29149083/co-precipitation-synthesis-and-optical-properties-of-mn-4-doped-hexafluoroaluminate-w-led-phosphors
#15
Tim Senden, Robin G Geitenbeek, Andries Meijerink
Mn(4+)-activated hexafluoroaluminates are promising red-emitting phosphors for white light emitting diodes (w-LEDs). Here, we report the synthesis of Na₃AlF₆:Mn(4+), K₃AlF₆:Mn(4+) and K₂NaAlF₆:Mn(4+) phosphors through a simple two-step co-precipitation method. Highly monodisperse large (~20 μm) smoothed-octahedron shaped crystallites are obtained for K₂NaAlF₆:Mn(4+). The large size, regular shape and small size distribution are favorable for application in w-LEDs. All Mn(4+)-doped hexafluoroaluminates show bright red Mn(4+) luminescence under blue light excitation...
November 17, 2017: Materials
https://www.readbyqxmd.com/read/29149063/estimating-stair-running-performance-using-inertial-sensors
#16
Lauro V Ojeda, Antonia M Zaferiou, Stephen M Cain, Rachel V Vitali, Steven P Davidson, Leia A Stirling, Noel C Perkins
Stair running, both ascending and descending, is a challenging aerobic exercise that many athletes, recreational runners, and soldiers perform during training. Studying biomechanics of stair running over multiple steps has been limited by the practical challenges presented while using optical-based motion tracking systems. We propose using foot-mounted inertial measurement units (IMUs) as a solution as they enable unrestricted motion capture in any environment and without need for external references. In particular, this paper presents methods for estimating foot velocity and trajectory during stair running using foot-mounted IMUs...
November 17, 2017: Sensors
https://www.readbyqxmd.com/read/29149054/a-dual-polymer-fiber-fizeau-interferometer-for-simultaneous-measurement-of-relative-humidity-and-temperature
#17
Chao-Tsung Ma, Yu-Wei Chang, Yuan-Jie Yang, Cheng-Ling Lee
This paper presents a novel design method in which a dual-polymer fiber Fizeau interferometer (DPFFI) is proposed for simultaneously measuring relative humidity (RH) and temperature (T). Since the polymer is intrinsically highly sensitive to both RH and T, the polymer fiber Fizeau interferometer (PFFI) exhibits cross-sensitivity of RH and T. In general, it is difficult to demodulate the optical responses from both variations of RH and T using a single PFFI. If two PFFIs with different structures are combined, they will individually exhibit distinct sensitivity responses with respect to RH and T, respectively...
November 17, 2017: Sensors
https://www.readbyqxmd.com/read/29149050/combining-a-disturbance-observer-with-triple-loop-control-based-on-mems-accelerometers-for-line-of-sight-stabilization
#18
Yong Luo, Yongmei Huang, Chao Deng, Yao Mao, Wei Ren, Qiongyan Wu
In the CCD-based fine tracking optical system (FTOS), the whole disturbance suppression ability (DSA) is the product of the inner loop and outer position loop. Traditionally, high sampling fiber-optic gyroscopes (FOGs) are added to the platform to stabilize the line-of-sight (LOS). However, because of the FOGs' high cost and relatively big volume relative to the back narrow space of small rotating mirrors, we attempt in this work to utilize a cheaper and smaller micro-electro-mechanical system (MEMS) accelerometer to build the inner loop, replacing the FOG...
November 17, 2017: Sensors
https://www.readbyqxmd.com/read/29148965/nonclinical-safety-assessment-of-anti-factor-d-key-strategies-and-challenges-for-the-nonclinical-development-of-intravitreal-biologics
#19
Vladimir Bantseev, Rebecca Erickson, Douglas Leipold, Caroline Amaya, Paul E Miller, Helen Booler, Evan A Thackaberry
PURPOSE: The nonclinical toxicology program described here was designed to characterize the safety profile of anti-factor D (AFD; FCFD4514S, lampalizumab) to support intravitreal (ITV) administration in patients with geographic atrophy (GA). METHODS: The toxicity of AFD was assessed in a single-dose and 6-month repeat-dose study in monkeys at doses up to 10 mg/eye. Toxicity was assessed by clinical ophthalmic examinations, intraocular pressure measurements, ocular photography, electroretinography, fluorescein angiography, optical coherence tomography, and anatomic pathology...
November 17, 2017: Journal of Ocular Pharmacology and Therapeutics
https://www.readbyqxmd.com/read/29148901/glaucoma-in-patients-with-shunt-treated-normal-pressure-hydrocephalus
#20
Pasquale Gallina, Alfonso Savastano, Eleonora Becattini, Simone Orlandini, Antonio Scollato, Stanislao Rizzo, Giulia Carreras, Nicola Di Lorenzo, Berardino Porfirio
OBJECTIVE Changes in the pressure gradient between intraocular and intracranial compartments at the lamina cribrosa level are a possible explanation of normal tension glaucoma (NTG). Shunt-treated normal pressure hydrocephalus (NPH) is a model for testing whether the increase (time from disease onset to CSF shunt placement, i.e., "protection period") and decrease (time from shunt placement to observation, i.e., "exposure period") in intracranial pressure (ICP) are glaucoma protective or risk factors, respectively...
November 17, 2017: Journal of Neurosurgery
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