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https://www.readbyqxmd.com/read/29793169/spontaneous-rise-in-open-rectangular-channels-under-gravity
#1
Vignesh Thammanna Gurumurthy, Ilia V Roisman, Cameron Tropea, Stephen Garoff
Fluid movement in microfluidic devices, porous media, and textured surfaces involves coupled flows over the faces and corners of the media. Spontaneous wetting of simple grooved surfaces provides a model system to probe these flows. This numerical study investigates the spontaneous rise of a liquid in an array of open rectangular channels under gravity, using the Volume-of-Fluid method with adaptive mesh refinement. The rise is characterized by the meniscus height at the channel center, outer face and the interior and exterior corners...
May 17, 2018: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/29791760/neopterin-7-8-dihydroneopterin-is-elevated-in-duchenne-muscular-dystrophy-patients-and-protects-mdx-skeletal-muscle-function
#2
Angus Lindsay, Alexandra Schmiechen, Christopher M Chamberlain, James M Ervasti, Dawn A Lowe
Macrophage infiltration is a hallmark of dystrophin-deficient muscle. We tested the hypothesis that Duchenne muscular dystrophy (DMD) patients would have elevated levels of the macrophage synthesized pterins, neopterin and 7,8-dihydroneopterin compared to unaffected age-matched controls. Urinary neopterin/creatinine and 7,8-dihydroneopterin/creatinine were elevated in DMD patients and 7,8-dihydroneopterin/creatinine was associated with patient age and ambulation. 7,8-dihydroneopterin correction with specific gravity was also elevated in DMD patients...
May 23, 2018: Experimental Physiology
https://www.readbyqxmd.com/read/29791378/design-of-an-adjustable-bipod-flexure-for-a-large-aperture-mirror-of-a-space-camera
#3
Bei Liu, Wei Wang, Yan-Jun Qu, Xu-Peng Li, Xiao Wang, Hui Zhao
An adjustable bipod flexure (ABF) technique for a large-aperture mirror of a space camera is presented. The proposed flexure mount can decrease the surface distortions caused by the machining error and the assembly error of the mirror assembly (MA) in a horizontal optical testing layout. Through the analysis of the compliance matrix of conventional bipod flexure, the positional relationship between the rotation center and the apex of the flexure is investigated. Then, the principle of the adjustable flexure, known as the trapezoidal switching principle, is proposed based on the analysis result...
May 20, 2018: Applied Optics
https://www.readbyqxmd.com/read/29789349/passive-water-collection-with-the-integument-mechanisms-and-their-biomimetic-potential
#4
REVIEW
Philipp Comanns
Several mechanisms of water acquisition have evolved in animals living in arid habitats to cope with limited water supply. They enable access to water sources such as rain, dew, thermally facilitated condensation on the skin, fog, or moisture from a damp substrate. This Review describes how a significant number of animals - in excess of 39 species from 24 genera - have acquired the ability to passively collect water with their integument. This ability results from chemical and structural properties of the integument, which, in each species, facilitate one or more of six basic mechanisms: increased surface wettability, increased spreading area, transport of water over relatively large distances, accumulation and storage of collected water, condensation, and utilization of gravity...
May 22, 2018: Journal of Experimental Biology
https://www.readbyqxmd.com/read/29789150/compensation-for-inertial-and-gravity-effects-in-a-moving-force-platform
#5
Sandra K Hnat, Ben J H van Basten, Antonie J van den Bogert
Force plates for human movement analysis provide accurate measurements when mounted rigidly on an inertial reference frame. Large measurement errors occur, however, when the force plate is accelerated, or tilted relative to gravity. This prohibits the use of force plates in human perturbation studies with controlled surface movements, or in conditions where the foundation is moving or not sufficiently rigid. Here we present a linear model to predict the inertial and gravitational artifacts using accelerometer signals...
May 19, 2018: Journal of Biomechanics
https://www.readbyqxmd.com/read/29789091/spinal-stiffness-in-prone-and-upright-postures-during-0-1-8-g-induced-by-parabolic-flight
#6
Jaap Swanenburg, Michael L Meier, Anke Langenfeld, Petra Schweinhardt, B Kim Humphreys
INTRODUCTION: The purpose of this study was to analyze posterior-to-anterior spinal stiffness in Earth, hyper-, and microgravity conditions during both prone and upright postures. CASE REPORT: During parabolic flight, the spinal stiffness of the L3 vertebra of a healthy 37-yr-old man was measured in normal Earth gravity (1.0 g), hypergravity (1.8 g), and microgravity (0.0 g) conditions induced in the prone and upright positions. Differences in spinal stiffness were significant across all three gravity conditions in the prone and upright positions...
June 1, 2018: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/29788241/microsurgical-treatment-of-distal-anterior-cerebral-artery-aneurysms-3-dimensional-operative-video
#7
Vijay Agarwal, Daniel L Barrow
Selecting appropriate patient position for surgery must take into consideration a variety of factors. For an interhemispheric approach to distal anterior cerebral artery (DACA) aneurysms, the patient may be positioned with the head either horizontal or vertical with respect to the floor. We preferentially place the patient in the supine position with the shoulder elevated and the head turned parallel to the floor with the side of the approach down and the vertex tilted 45° up. In this way, gravity is utilized to allow the right frontal lobe to fall away from the falx, eliminating the need for retraction...
May 18, 2018: Operative Neurosurgery (Hagerstown, Md.)
https://www.readbyqxmd.com/read/29786064/fabrication-of-aluminum-alloy-functionally-graded-material-using-directional-solidification-under-an-axial-static-magnetic-field
#8
Shaodong Hu, Annie Gagnoud, Yves Fautrelle, Rene Moreau, Xi Li
Aluminum alloy in situ functionally graded materials (FGMs) have been successfully fabricated using directional solidification under an axial static magnetic field. Al-Zn, Al-Ni and Al-Cu alloys with a hypereutectic composition were selected to produce FGMs. Experimental results show that the graded composition of the primary phases (i.e., Zn, Al3 Ni and Al2 Cu) is obvious along the longitudinal section of the sample. The graded composition of the primary phases could be controlled by the value of the magnetic field, growth rate and temperature gradient...
May 21, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29785723/decreased-e-cadherin-in-mcf7-human-breast-cancer-cells-forming-multicellular-spheroids-exposed-to-simulated-microgravity
#9
Jayashree Sahana, Mohamed Zakaria Nassef, Markus Wehland, Sascha Kopp, Marcus Krüger, Thomas J Corydon, Manfred Infanger, Johann Bauer, Daniela Grimm
MCF7 human breast cancer cells were cultured under normal gravity (1g) and on a random positioning machine (RPM) preventing sedimentation. After two weeks, adherent 1g-control and adherent RPM cells (AD) as well as multicellular spheroids (MCS) were harvested. AD and MCS had been exposed to the RPM in the same culture flask. In a subsequent proteome analysis, the majority of the proteins detected showed similar label-free quantification scores (LFQ) in each of the respective subpopulations, but in both AD or MCS cultures, proteins were also found whose LFQs deviated at least twofold from their counterparts in the 1g-control cells...
May 21, 2018: Proteomics
https://www.readbyqxmd.com/read/29785010/genome-wide-analyses-identify-68-new-loci-associated-with-intraocular-pressure-and-improve-risk-prediction-for-primary-open-angle-glaucoma
#10
Anthony P Khawaja, Jessica N Cooke Bailey, Nicholas J Wareham, Robert A Scott, Mark Simcoe, Robert P Igo, Yeunjoo E Song, Robert Wojciechowski, Ching-Yu Cheng, Peng T Khaw, Louis R Pasquale, Jonathan L Haines, Paul J Foster, Janey L Wiggs, Chris J Hammond, Pirro G Hysi
Glaucoma is the leading cause of irreversible blindness globally 1 . Despite its gravity, the disease is frequently undiagnosed in the community 2 . Raised intraocular pressure (IOP) is the most important risk factor for primary open-angle glaucoma (POAG)3,4 . Here we present a meta-analysis of 139,555 European participants, which identified 112 genomic loci associated with IOP, 68 of which are novel. These loci suggest a strong role for angiopoietin-receptor tyrosine kinase signaling, lipid metabolism, mitochondrial function and developmental processes underlying risk for elevated IOP...
May 21, 2018: Nature Genetics
https://www.readbyqxmd.com/read/29783793/summary-of-u-s-injuries-and-fatalities-involving-entrapment-and-suffocation-in-grain-transport-vehicles
#11
Yuan-Hsin Cheng, William E Field, Salah F Issa, Kevin Kelley, Matthew Heber, Robert Turner
Since 1978, the Purdue University Agricultural Safety and Health Program has managed a surveillance effort and database to collect information on documented injuries and fatalities in all forms of U.S. agricultural confined spaces. The database currently contains 1,968 cases documented in the U.S. between 1964 and 2016. Of these cases, 174 (8.8%) involved entrapment or suffocation in grain transport vehicles (GTVs), including gravity-flow wagons, semi-truck trailers, and other agricultural transport vehicles that have limited access and are not considered normal work spaces or are classified as confined spaces...
May 7, 2018: Journal of Agricultural Safety and Health
https://www.readbyqxmd.com/read/29783216/-complex-of-psycho-hygienic-correction-measures-of-personality-features-of-hiv-infected-men-and-evaluation-of-their-efficiency
#12
Ihor V Serheta, Oksana B Dudarenko, Olha P Mostova, Tetiana V Lobastova, Vitalii M Andriichuk, Larysa M Vakolyuk, Olha M Yakubovska
OBJECTIVE: Introduction: In addition to adequate diagnosis and treatment of HIV-infected individuals, development, scientific substantiation and implementation of psycho-hygienic measures aimed at correcting the processes of forming personality traits and improving the psycho-emotional state of HIV-infected individuals are of particular importance. The aim: The purpose of the scientific research was to determine the most significant changes of situational and personal anxiety indicators, the degree of gravity of the asthenic state and depressive manifestations that were recorded in the context of the introduction of a number of measures for psycho-hygienic correction...
2018: Wiadomości Lekarskie: Organ Polskiego Towarzystwa Lekarskiego
https://www.readbyqxmd.com/read/29780200/growing-fresh-food-on-future-space-missions-environmental-conditions-and-crop-management
#13
Esther Meinen, Tom Dueck, Frank Kempkes, Cecilia Stanghellini
This paper deals with vegetable cultivation that could be faced in a space mission. This paper focusses on optimization, light, temperature and the harvesting process, while other factors concerning cultivation in space missions, i.e. gravity, radiation, were not addressed. It describes the work done in preparation of the deployment of a mobile test facility for vegetable production of fresh food at the Neumayer III Antarctic research station. A selection of vegetable crops was grown under varying light and temperature conditions to quantify crop yield response to climate factors that determine resource requirement of the production system...
May 17, 2018: Scientia Horticulturae
https://www.readbyqxmd.com/read/29779829/leveling-the-playing-field-evaluation-of-a-portable-instrument-for-quantifying-balance-performance
#14
Sutton B Richmond, Kevin D Dames, Daniel J Goble, Brett W Fling
Balance is a complex, sensorimotor task requiring an individual to maintain the center of gravity within the base of support. Quantifying balance in a reliable and valid manner is essential to evaluating disease progression, aging complications, and injuries in clinical and research settings. Typically, researchers use force plates to track motion of the center of gravity during a variety of tasks. However, limiting factors such as cost, portability, and availability have hindered postural stability evaluation in these settings...
May 17, 2018: Journal of Biomechanics
https://www.readbyqxmd.com/read/29776585/tears-of-wine-the-dance-of-the-droplets
#15
REVIEW
Alex Nikolov, Darsh Wasan, Jongju Lee
For a long time, the phenomenon known as the "tears of wine" was believed to be due only to the surface tension gradient (e.g., the Thomson-Marangoni stress on the fluid/fluid surface's dynamics of wetting) and gravity. We experimentally demonstrated that the wine tear formation is not solely due to the surface tension gradient; instead, the ridge instability triggers the wine tears. Pouring wine into a glass causes a wine film to form on the glass. The film drains down under gravity and a ridge forms at its upper part...
May 5, 2018: Advances in Colloid and Interface Science
https://www.readbyqxmd.com/read/29775337/effective-inertial-frame-in-an-atom-interferometric-test-of-the-equivalence-principle
#16
Chris Overstreet, Peter Asenbaum, Tim Kovachy, Remy Notermans, Jason M Hogan, Mark A Kasevich
In an ideal test of the equivalence principle, the test masses fall in a common inertial frame. A real experiment is affected by gravity gradients, which introduce systematic errors by coupling to initial kinematic differences between the test masses. Here we demonstrate a method that reduces the sensitivity of a dual-species atom interferometer to initial kinematics by using a frequency shift of the mirror pulse to create an effective inertial frame for both atomic species. Using this method, we suppress the gravity-gradient-induced dependence of the differential phase on initial kinematic differences by 2 orders of magnitude and precisely measure these differences...
May 4, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29775330/constraining-alternative-theories-of-gravity-using-pulsar-timing-arrays
#17
Neil J Cornish, Logan O'Beirne, Stephen R Taylor, Nicolás Yunes
The opening of the gravitational wave window by ground-based laser interferometers has made possible many new tests of gravity, including the first constraints on polarization. It is hoped that, within the next decade, pulsar timing will extend the window by making the first detections in the nanohertz frequency regime. Pulsar timing offers several advantages over ground-based interferometers for constraining the polarization of gravitational waves due to the many projections of the polarization pattern provided by the different lines of sight to the pulsars, and the enhanced response to longitudinal polarizations...
May 4, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29774084/a-novel-dual-well-array-chip-for-efficiently-trapping-single-cell-in-large-isolated-micro-well-without-complicated-accessory-equipment
#18
Chenyu Wang, Wenwen Liu, Qingquan Wei, Lufeng Ren, Manqing Tan, Yude Yu
Conventional cell-sized well arrays have advantages of high occupancy, simple operation, and low cost for capturing single-cells. However, they have insufficient space for including reagents required for cell treatment or analysis, which restricts the wide application of cell-sized well arrays as a single-cell research tool alone. Here, we present a novel dual-well array chip, which integrates capture-wells (20  μ m in diameter) with reaction-wells (100  μ m in diameter) and describe a flow method for convenient single-cell analysis requiring neither complicated infra-structure nor high expenditure, while enabling highly efficient single cell trapping (75...
May 2018: Biomicrofluidics
https://www.readbyqxmd.com/read/29773849/the-crotone-megalandslide-southern-italy-architecture-timing-and-tectonic-control
#19
Massimo Zecchin, Flavio Accaino, Silvia Ceramicola, Dario Civile, Salvatore Critelli, Cristina Da Lio, Giacomo Mangano, Giacomo Prosser, Pietro Teatini, Luigi Tosi
Large-scale submarine gravitational land movements involving even more than 1,000 m thick sedimentary successions are known as megalandslides. We prove the existence of large-scale gravitational phenomena off the Crotone Basin, a forearc basin located on the Ionian side of Calabria (southern Italy), by seismic, morpho-bathymetric and well data. Our study reveals that the Crotone Megalandslide started moving between Late Zanclean and Early Piacenzian and was triggered by a contractional tectonic event leading to the basin inversion...
May 17, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29773841/ocular-counter-rolling-in-astronauts-after-short-and-long-duration-spaceflight
#20
Millard F Reschke, Scott J Wood, Gilles Clément
Ocular counter-rolling (OCR) is a reflex generated by the activation of the gravity sensors in the inner ear that stabilizes gaze and posture during head tilt. We compared the OCR measures that were obtained in 6 astronauts before, during, and after a spaceflight lasting 4-6 days with the OCR measures obtained from 6 astronauts before and after a spaceflight lasting 4-9 months. OCR in the short-duration fliers was measured using the afterimage method during head tilt at 15°, 30°, and 45°. OCR in the long-duration fliers was measured using video-oculography during whole body tilt at 25°...
May 17, 2018: Scientific Reports
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