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https://www.readbyqxmd.com/read/29456268/evidence-for-ubiquitous-preferential-particle-orientation-in-representative-oceanic-shear-flows
#1
Aditya R Nayak, Malcolm N McFarland, James M Sullivan, Michael S Twardowski
In situ measurements were undertaken to characterize particle fields in undisturbed oceanic environments. Simultaneous, co-located depth profiles of particle fields and flow characteristics were recorded using a submersible holographic imaging system and an acoustic Doppler velocimeter, under different flow conditions and varying particle concentration loads, typical of those found in coastal oceans and lakes. Nearly one million particles with major axis lengths ranging from ∼14 μm to 11.6 mm, representing diverse shapes, sizes, and aspect ratios were characterized as part of this study...
January 2018: Limnology and Oceanography
https://www.readbyqxmd.com/read/29456258/modifying-the-standard-disk-model-for-the-ultraviolet-spectral-analysis-of-disk-dominated-cataclysmic-variables-i-the-novalikes-mv-lyrae-bz-camelopardalis-and-v592-cassiopeiae
#2
Patrick Godon, Edward M Sion, Şölen Balman, William P Blair
The standard disk is often inadequate to model disk-dominated cataclysmic variables (CVs) and generates a spectrum that is bluer than the observed UV spectra. X-ray observations of these systems reveal an optically thin boundary layer (BL) expected to appear as an inner hole in the disk. Consequently, we truncate the inner disk. However, instead of removing the inner disk, we impose the no-shear boundary condition at the truncation radius, thereby lowering the disk temperature and generating a spectrum that better fits the UV data...
September 1, 2017: Astrophysical Journal
https://www.readbyqxmd.com/read/29456174/bilateral-maculopathy-after-exposure-to-a-laser-pointer-optical-coherence-tomography-angiography-findings
#3
R Clemente-Tomás, P Bayo-Calduch, P Neira-Ibáñez, A Gargallo-Benedicto, A M Duch-Samper
CASE REPORT: A 36-year-old man went to the emergency department the day after exposure to a laser pointer. Funduscopy revealed dispersed macular pigment alterations, and optical coherence tomography showed a disruption of the retinal layers. The visual acuity was counting fingers in both eyes. Nine months later, optical coherence tomography angiography showed a rarefaction in the choriocapillaris vascular flow in the area of the laser injuries. DISCUSSION: The retinal layer mainly damaged by the laser injury was the retinal pigment epithelium...
February 15, 2018: Archivos de la Sociedad Española de Oftalmología
https://www.readbyqxmd.com/read/29454231/influence-of-heading-perception-in-the-control-of-posture
#4
Alessandro Piras, Milena Raffi, Monica Perazzolo, Salvatore Squatrito
The optic flow visual input directly influences the postural control. The aim of the present study was to examine the relationship between visually induced heading perception and postural stability, using optic flow stimulation. The dots were accelerated to simulate a heading direction to the left or to the right of the vertical midline. The participants were instructed to indicate the perceived optic flow direction by making a saccade to the simulated heading direction. We simultaneously acquired electromyographyc and center of pressure (COP) signals...
February 10, 2018: Journal of Electromyography and Kinesiology
https://www.readbyqxmd.com/read/29450473/elevated-blood-viscosity-and-micro-recirculation-linked-to-coronary-stent-malapposition
#5
Eric Poon, Vikas Thondapu, Umair Hayat, Peter Barlis, Chooi Yap, Po Kuo, Qisen Wang, Jiawei Ma, Shuang Zhu, Stephen Moore, Andrew Ooi
One particular complexity of coronary artery is the natural tapering of the vessel with proximal segments having larger caliber and distal tapering as the vessel get smaller. The natural tapering of a coronary artery often leads to proximal incomplete stent apposition (ISA). ISA alters coronary hemodynamics and creates pathological path to develop complications such as in-stent restenosis, and more worryingly, stent thrombosis. By employing state-of-the-art computer-aided design software, generic stent hoops were virtually deployed in an idealized tapered coronary artery with decreasing malapposition distance...
February 14, 2018: Journal of Biomechanical Engineering
https://www.readbyqxmd.com/read/29448409/ultrasonic-measurements-of-the-bulk-flow-field-in-foams
#6
Richard Nauber, Lars Büttner, Kerstin Eckert, Jochen Fröhlich, Jürgen Czarske, Sascha Heitkam
The flow field of moving foams is relevant for basic research and for the optimization of industrial processes such as froth flotation. However, no adequate measurement technique exists for the local velocity distribution inside the foam bulk. We have investigated the ultrasound Doppler velocimetry (UDV), providing the first two-dimensional, non-invasive velocity measurement technique with an adequate spatial (10mm) and temporal resolution (2.5Hz) that is applicable to medium scale foam flows. The measurement object is dry aqueous foam flowing upward in a rectangular channel...
January 2018: Physical Review. E
https://www.readbyqxmd.com/read/29448283/-significance-of-endothelin-1-in-glaucoma-a-short-overview
#7
Konstantin Gugleta
This review article is focused on the various facets of possible endothelin's role in glaucoma; involvement of endothelin in other ocular, in particular vascular, diseases is not specifically discussed. Endothelin is an ubiquitous molecule that occurs in practically all ocular tissues. Its primary physiological function is regulation of the blood vessel diameter and hence regulation of the blood supply in tissues. It is secreted locally, and exerts its effect also predominantly locally. This limits the value of venous blood sampling for estimation of the endothelin function in a particular patient, or in study cohorts as well...
February 2018: Klinische Monatsblätter Für Augenheilkunde
https://www.readbyqxmd.com/read/29446235/quantitative-evaluation-of-the-performance-of-different-deformable-image-registration-algorithms-in-helical-axial-and-cone-beam-ct-images-using-a-mobile-phantom
#8
Imad Ali, Nesreen Alsbou, Justin Jaskowiak, Salahuddin Ahmad
The goal of this project is to investigate quantitatively the performance of different deformable image registration algorithms (DIR) with helical (HCT), axial (ACT), and cone-beam CT (CBCT). The variations in the CT-number values and lengths of well-known targets moving with controlled motion were evaluated. Four DIR algorithms: Demons, Fast-Demons, Horn-Schunck and Lucas-Kanade were used to register intramodality CT images of a mobile phantom scanned with different imaging techniques. The phantom had three water-equivalent targets inserted in a low-density foam with different lengths (10-40 mm) and moved with adjustable motion amplitudes (0-20 mm) and frequencies (0-0...
February 15, 2018: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/29445833/functionalized-au-ag-au-nanoparticles-as-an-optical-and-sers-dual-probe-for-lateral-flow-sensing
#9
Tingting Bai, Meng Wang, Min Cao, Juan Zhang, Kangzhen Zhang, Ping Zhou, Zhengxia Liu, Ying Liu, Zhirui Guo, Xiang Lu
Lateral flow assay strips (LFASs) with Au nanoparticles (NPs) have been widely used as a probe for biomarkers in point-of-care testing; however, there still remain challenges in detection sensitivity and quantitative analysis. In this study, we developed a surface-enhanced Raman scattering (SERS)-based LFAS for quantitative analysis of a biomarker in the low concentration range. Moreover, apart from conventional Au NPs, three other types of citrate-capped Au-Ag bimetallic NPs: Au core with Ag shell NPs (Au@Ag NPs), rattle-like Au core in Ag-Au shell NPs (Au@Ag-Au NPs) and Ag-Au NPs were prepared and functionalized, and their solution-based SERS activities were comprehensively studied by experimental measurement and theoretical analysis...
February 14, 2018: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29444069/optical-spectral-sweep-comb-liquid-flow-rate-sensor
#10
Changyu Shen, Xiaokang Lian, Vishnu Kavungal, Chuan Zhong, Dejun Liu, Yuliya Semenova, Gerald Farrell, Jacques Albert, John F Donegan
In microfluidic chip applications, the flow rate plays an important role. Here we propose a simple liquid flow rate sensor by using a tilted fiber Bragg grating (TFBG) as the sensing element. As the water flows in the vicinity of the TFBG along the fiber axis direction, the TFBG's spectrum changes due to its contact with water. By comparing the time-swept spectra of the TFBG in water to that of the TFBG with water flowing over it, a spectral sweep comb was formed, and the flow rate can be detected by selecting a suitable sweeping frequency...
February 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/29443780/analysis-of-the-characteristics-of-optical-coherence-tomography-angiography-for-retinal-cavernous-hemangioma-a-case-report
#11
Shuyuan Lyu, Ming Zhang, Ruikang K Wang, Yunxia Gao, Qinqin Zhang, Xiaoxue Min
RATIONALE: Retinal cavernous hemangioma is a rare congenital vascular malformation with typical fundus changes. Optical coherence tomography angiography (OCTA), which is in rise in the recent years, is a rapid and noninvasive technology to assist in obtaining information regarding the blood flow changes in the fundus lesions from different layers without injecting a contrast agent. PATIENT CONCERNS: A 40-year-old male patient with visual occlusion in the right eye for >1 month was reported...
February 2018: Medicine (Baltimore)
https://www.readbyqxmd.com/read/29443360/swept-source-oct-angiography-of-full-thickness-macular-holes-appearance-and-artifacts
#12
Zofia Michalewska, Jerzy Nawrocki
BACKGROUND AND OBJECTIVE: To evaluate swept-source optical coherence tomography angiography (SS-OCTA) images in full-thickness macular holes (FTMHs). PATIENTS AND METHODS: SS-OCTA of FTMHs was performed before or after surgery. Vitrectomy with the temporal inverted internal limiting membrane flap technique was used. The authors measured the diameter and area of the foveal avascular zone (FAZ) in superficial and deep retina vasculature. RESULTS: In 88 patients, two artifact types were observed...
February 1, 2018: Ophthalmic Surgery, Lasers & Imaging Retina
https://www.readbyqxmd.com/read/29442245/retrobulbar-and-intraocular-blood-flow-in-anterior-ischaemic-optic-neuropathy-are-linked-to-the-functional-impairment
#13
David Kuerten, Matthias Fuest, Marion Bienert, Niklas Plange
PURPOSE: Evaluation of ocular haemodynamics in patients with acute non-arteritic anterior ischaemic optic neuropathy (NAION) by colour Doppler imaging and fluorescein angiography and correlation of blood flow parameters to visual field loss and visual acuity. METHODS: Blood flow velocities (peak systolic velocity (PSV), end-diastolic velocity (EDV)) of the ophthalmic artery (OA), central retinal artery (CRA) and nasal and temporal posterior ciliary arteries (PCAs) were measured via colour Doppler imaging...
February 13, 2018: International Ophthalmology
https://www.readbyqxmd.com/read/29440700/age-related-changes-in-the-response-of-retinal-structure-function-and-blood-flow-to-pressure-modification-in-rats
#14
Da Zhao, Christine T O Nguyen, Zheng He, Vickie H Y Wong, Anna K van Koeverden, Algis J Vingrys, Bang V Bui
Age-related changes to the balance between the pressure inside the eye (intraocular pressure, IOP) and the pressure inside the brain (intracranial pressure, ICP) can modify the risk of glaucoma. In this study, we consider whether the optic nerve in older rat eyes is more susceptible to acute IOP and ICP modification. We systematically manipulate both ICP and IOP and quantify their effects on ganglion cell function (electroretinography, ERG), optic nerve structure (optical coherence tomography, OCT) and retinal blood flow (Doppler OCT)...
February 13, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29439517/hyperglycemia-alters-the-structure-and-hemodynamics-of-the-developing-embryonic-heart
#15
Taylor B Lawson, Devon E Scott-Drechsel, Venkat Keshav Chivukula, Sandra Rugonyi, Kent L Thornburg, Monica T Hinds
Congenital heart defects (CHDs) represent the most common form of human birth defects; approximately one-third of heart defects involve malformations of the outflow tract (OFT). Maternal diabetes increases the risk of CHD by 3-5 fold. During heart organogenesis, little is known about the effects of hyperglycemia on hemodynamics, which are critical to normal heart development. Heart development prior to septation in the chick embryo was studied under hyperglycemic conditions. Sustained hyperglycemic conditions were induced, raising the average plasma glucose concentration from 70 mg/dL to 180 mg/dL, akin to the fasting plasma glucose of a patient with diabetes...
February 12, 2018: Journal of Cardiovascular Development and Disease
https://www.readbyqxmd.com/read/29437379/separations-at-the-speed-of-sensors
#16
Darshan C Patel, M Farooq Wahab, Thomas C O'Haver, Daniel W Armstrong
The virtue of chemical sensors is speed and analyte specificity. The response time to generate an analytical signal typically varies from ∼1 to 20 s, and they are generally limited to a single analyte. Chemical sensors are significantly affected by multiple interferents, matrix effects, temperature, and can vary widely in sensitivity depending on the sensor format. Separation-based analyses remove matrix effects and interferents and are compatible with multiple analytes. However, the speed of such analyses has not been commensurate with traditional sensors until now...
February 13, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29436224/dynamic-stocks-and-flows-analysis-of-bisphenol-a-bpa-in-china-2000-2014
#17
Daqian Jiang, Wei-Qiang Chen, Xianlai Zeng, Linbin Tang
Bisphenol A (BPA), a synthetic organic chemical, is creating a new category of ecological and human health challenges due to unintended leakage. Effectively managing the use and leakage of BPA can benefit from an understanding of the anthropogenic BPA cycle (i.e., the size of BPA flows and stocks). In this work, we provide a dynamic analysis of the anthropogenic BPA cycle in China for 2000-2014. We find that China's BPA inflows haveconsumption has increased 10-fold since 2000, to approximately ~3 million tonnes/year...
February 13, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29436153/advanced-imaging-technology-applications-in-cytology
#18
Liron Pantanowitz, Frederic Preffer, David C Wilbur
Novel techniques have been developed to image cells at cellular and subcellular levels. They allow images to be analyzed with ultra-high resolution, in 2D and/or 3D. Several of these tools have been tested on cytology specimens demonstrating emerging applications that are likely to change the field of cytopathology. This review covers several of these advanced imaging methods. The use of optical coherence tomography to perform optical biopsies during endoscopic ultrasound procedures or visualize cells within effusion samples is discussed...
February 12, 2018: Diagnostic Cytopathology
https://www.readbyqxmd.com/read/29434227/the-nlrp3-inflammasome-may-contribute-to-pathologic-neovascularization-in-the-advanced-stages-of-diabetic-retinopathy
#19
Shyam S Chaurasia, Rayne R Lim, Bhav H Parikh, Yeo Sia Wey, Bo Bo Tun, Tien Yin Wong, Chi D Luu, Rupesh Agrawal, Arkasubhra Ghosh, Alessandra Mortellaro, Elizabeth Rackoczy, Rajiv R Mohan, Veluchamy A Barathi
Diabetic retinopathy (DR) is a retinal microvascular disease characterized by inflammatory and angiogenic pathways. In this study, we evaluated NLRP3 inflammasome in a double transgenic mouse model, Akimba (Ins2 Akita xVEGF +/- ), which demonstrates hyperglycemia, vascular hyperpermeability and neovascularization seen in the proliferative DR. Retinal structural integrity, vascular leakage and function were examined by fundus photography, fluorescein angiography, optical coherence tomography, retinal flat mounts, laser speckle flowgraphy (LSFG), and electroretinography in Akimba and its parental strains, Akita (Ins2 Akita ) and Kimba (trVEGF029) mice...
February 12, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29433261/spoilage-potential-of-brettanomyces-bruxellensis-strains-isolated-from-italian-wines
#20
Raffaele Guzzon, Roberto Larcher, Rosa Guarcello, Nicola Francesca, Luca Settanni, Giancarlo Moschetti
Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B...
March 2018: Food Research International
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