Read by QxMD icon Read

A-a gradient

Itsuko Tsukimura, Hideki Murakami, Makoto Sasaki, Hirooki Endo, Daisuke Yamabe, Ryosuke Oikawa, Minoru Doita
The safety of metallic spinal implants in magnetic resonance imaging (MRI) performed using ultrahigh fields has not been established. Hence, we examined whether the displacement forces caused by a static magnetic field and the heating induced by radiofrequency radiation are substantial for spinal implants in a 7 T field. We investigated spinal rods of various lengths and materials, a screw, and a cross-linking bridge in accordance with the American Society for Testing and Materials guidelines. The displacement forces of the metallic implants in static 7 T and 3 T static magnetic fields were measured and compared...
October 21, 2016: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
Tommaso Michele Moles, Antonio Pompeiano, Thais Huarancca Reyes, Andrea Scartazza, Lorenzo Guglielminetti
Landraces represent an important part of the biodiversity well-adapted under limiting environmental conditions. We investigated the response of two Southern Italy tomato landraces, the well-known San Marzano (our commercial standard) and a local accession called "Ciettaicale", to different levels of sodium chloride in water irrigation (from 0 up to 600 mM) for a short-time exposure (one week). The combination of the chlorophyll a fluorescence and gas exchange analyses suggested that Ciettaicale maintained a higher efficiency of photosystem II (PSII) photochemistry and CO2 utilization at high salinity concentrations than San Marzano...
October 12, 2016: Plant Physiology and Biochemistry: PPB
Xiang-Xin Huang, Yun-Xuan Li, Xiang-Yu Li, Xiao-Xia Hu, Peng-Fei Tang, Guo-Xin Hu
Currently, crizotinib is the first generation drug, which has been used in the treatment of ALK-rearranged non-small cell lung cancer (NSCLC). However, more and more patients are found in crizotinib-resistance. In the last year, alectinib has been approved for treatment of patients with crizotinib-resistance. In this study, we aim to develop and validate a simple, rapid and sensitive tandem mass spectrometry (UHPLC-MS/MS) method for determination of alectinib in rat plasma. Diazepam was chosen as an internal standard (IS)...
October 14, 2016: Journal of Pharmaceutical and Biomedical Analysis
Yadvinder Malhi, Cécile A J Girardin, Gregory R Goldsmith, Christopher E Doughty, Norma Salinas, Daniel B Metcalfe, Walter Huaraca Huasco, Javier E Silva-Espejo, Jhon Del Aguilla-Pasquell, Filio Farfán Amézquita, Luiz E O C Aragão, Rossella Guerrieri, Françoise Yoko Ishida, Nur H A Bahar, William Farfan-Rios, Oliver L Phillips, Patrick Meir, Miles Silman
Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation. We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru. Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy...
October 21, 2016: New Phytologist
Tânia Nobre, Manuela Oliveira, Birgit Arnholdt-Schmitt
By definition, the domestication process leads to an overall reduction of crop genetic diversity. This lead to the current search of genomic regions in wild crop relatives (CWR), an important task for modern carrot breeding. Nowadays massive sequencing possibilities can allow for discovery of novel genetic resources in wild populations, but this quest could be aided by the use of a surrogate gene (to first identify and prioritize novel wild populations for increased sequencing effort). Alternative oxidase (AOX) gene family seems to be linked to all kinds of abiotic and biotic stress reactions in various organisms and thus have the potential to be used in the identification of CWR hotspots of environment-adapted diversity...
2016: PloS One
Srikanth Boddu, Marc Dinkin, Maria Suurna, Kelly Hannsgen, Xem Bui, Athos Patsalides
OBJECTIVE: Evaluate the role of venous sinus stenting in the treatment of pulsatile tinnitus among patients with Idiopathic Intracranial Hypertension (IIH) and significant venous sinus stenosis. SUBJECTS AND METHODS: A written informed consent approved by the Weill Cornell institutional review board was signed and obtained from the study participants. Thirty-seven consecutive patients with IIH and venous sinus stenosis who were treated with venous sinus stenting between Jan...
2016: PloS One
Ruben Perez-Carrasco, Pilar Guerrero, James Briscoe, Karen M Page
During tissue development, patterns of gene expression determine the spatial arrangement of cell types. In many cases, gradients of secreted signalling molecules-morphogens-guide this process by controlling downstream transcriptional networks. A mechanism commonly used in these networks to convert the continuous information provided by the gradient into discrete transitions between adjacent cell types is the genetic toggle switch, composed of cross-repressing transcriptional determinants. Previous analyses have emphasised the steady state output of these mechanisms...
October 2016: PLoS Computational Biology
Stefan Kramel, Greg A Voth, Saskia Tympel, Federico Toschi
We introduce a new particle shape which shows preferential rotation in three dimensional homogeneous isotropic turbulence. We call these particles chiral dipoles because they consist of a rod with two helices of opposite handedness, one at each end. 3D printing is used to fabricate these particles with a length in the inertial range and their rotations are tracked in a turbulent flow between oscillating grids. High aspect ratio chiral dipoles preferentially align with their long axis along the extensional eigenvectors of the strain rate tensor, and the helical ends respond to the extensional strain rate with a mean spinning rate that is nonzero...
October 7, 2016: Physical Review Letters
Markus Ahlers
Recent measurements of the dipole anisotropy in the arrival directions of Galactic cosmic rays (CRs) indicate a strong energy dependence of the dipole amplitude and phase in the TeV-PeV range. We argue here that these observations can be well understood within standard diffusion theory as a combined effect of (i) one or more local sources at Galactic longitude 120°≲l≲300° dominating the CR gradient below 0.1-0.3 PeV, (ii) the presence of a strong ordered magnetic field in our local environment, (iii) the relative motion of the solar system, and (iv) the limited reconstruction capabilities of ground-based observatories...
October 7, 2016: Physical Review Letters
Yiwen Li Hegner, Axel Lindner, Christoph Braun
The processes underlying perceptual decision making are diverse and typically engage a distributed network of brain areas. It is a particular challenge to establish a sensory-to-motor functional hierarchy in such networks. This is because single-cell recordings mainly study the nodes of decision networks in isolation but seldom simultaneously. Moreover, imaging methods, which allow simultaneously accessing information from overall networks, typically suffer from either the temporal or the spatial resolution necessary to establish a detailed functional hierarchy in terms of a sequential recruitment of areas during a decision process...
October 21, 2016: Human Brain Mapping
I Absah, A Rishi, N J Talley, D Katzka, M Halland
BACKGROUND: Rumination syndrome is a functional gastrointestinal disorder characterized by effortless and repetitive regurgitation of recently ingested food from the stomach to the oral cavity followed by either re-swallowing or spitting. Rumination is thought to occur due to a reversal of the esophagogastric pressure gradient. This is achieved by a coordinated abdominothoracic maneuver consisting of a thoracic suction, crural diaphragm relaxation and an increase in intragastric pressure...
October 20, 2016: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
Sungheon Gene Kim, Melanie Freed, Ana Paula Klautau Leite, Jin Zhang, Claudia Seuss, Linda Moy
PURPOSE: To assess the diagnostic utility of contrast kinetic analysis for breast lesions and background parenchyma of women undergoing MRI-guided biopsies, for whom standard clinical analysis had failed to separate benign and malignant lesions. MATERIALS AND METHODS: This study included 115 women who had indeterminate lesions based on routine diagnostic breast MRI exams and underwent an MRI (3 Tesla) -guided biopsy of one or more lesions suspicious for breast cancer...
October 20, 2016: Journal of Magnetic Resonance Imaging: JMRI
Neha Kumari, Rajesh Kumar, Vandana Mishra, Savita Yadav
CC-NBS-LRR (CNL) plant proteins are related with highly conserved family of disease resistance protein distinguished by a coiled-coil domain, which plays an important role in innate immunity. The present study reports the purification and identification of CNL like protein fragment (CNL-LPF) by two step chromatography and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF/MS), respectively. Furthermore, current study also illustrated the development of polyclonal antibody against purified CNL-LPF, which was used for immunolocalization of CNL-LPF in cytoplasm of cotyledon, using Fluorescence microscopy and Transmission electron microscopy...
October 20, 2016: Protein Journal
N Fahrenfeld, A Pruden, M Widdowson
Methyl ethyl ketone (MEK) is a common groundwater contaminant often present with more toxic compounds of primary interest. Because of this, few studies have been performed to determine the effect of microbial community structure on MEK biodegradation rates in aquifer sediments. Here, microcosms were prepared with aquifer sediments containing MEK following a massive spill event and compared to laboratory-spiked sediments, with MEK biodegradation rates quantified under mixed aerobic/anaerobic conditions. Biodegradation was achieved in MEK-contaminated site sediment microcosms at about half of the solubility (356 mg/L) with largely Firmicutes population under iron-reducing conditions...
October 20, 2016: Biodegradation
Abel Santos, Cheryl Suwen Law, Dominique Wong Chin Lei, Taj Pereira, Dusan Losic
In this study, we present an advanced nanofabrication approach to produce gradient-index photonic crystal structures based on nanoporous anodic alumina. An apodization strategy is for the first time applied to a sinusoidal pulse anodisation process in order to engineer the photonic stop band of nanoporous anodic alumina (NAA) in depth. Four apodization functions are explored, including linear positive, linear negative, logarithmic positive and logarithmic negative, with the aim of finely tuning the characteristic photonic stop band of these photonic crystal structures...
October 21, 2016: Nanoscale
Carlos E Hernandez-Tamargo, Ransel Barzaga, Hans Mikosch, Javier A Martínez, José A Herrera, M H Farías, Mayra P Hernández
The adsorption of sulphur multilayers on Au(100) has been studied using density functional theory (DFT) within the generalized gradient approximation (GGA). The first sulphur layer was adsorbed on the four-fold sites of the unreconstructed Au(100) surface forming a lattice. The experimental parameters of the lattice were reproduced taking into account the surface expansion of the topmost Au(100) layer. This expansion should occur when gold islands are formed after the lifting of hex-reconstruction, which allows the lateral movement of the gold atoms...
October 21, 2016: Physical Chemistry Chemical Physics: PCCP
Richard J McMurtrey
Biomaterials are becoming an essential tool in the study and application of stem cell research. Various types of biomaterials enable three-dimensional culture of stem cells, and, more recently, also enable high-resolution patterning and organization of multicellular architectures. Biomaterials also hold potential to provide many additional advantages over cell transplants alone in regenerative medicine. This article describes novel designs for functionalized biomaterial constructs that guide tissue development to targeted regional identities and structures...
January 2016: Journal of Tissue Engineering
Donghwan Kim, Jeffrey A Fessler
We introduce new optimized first-order methods for smooth unconstrained convex minimization. Drori and Teboulle [5] recently described a numerical method for computing the N-iteration optimal step coefficients in a class of first-order algorithms that includes gradient methods, heavy-ball methods [15], and Nesterov's fast gradient methods [10,12]. However, the numerical method in [5] is computationally expensive for large N, and the corresponding numerically optimized first-order algorithm in [5] requires impractical memory and computation for large-scale optimization problems...
September 2016: Mathematical Programming
Karen Peynshaert, Stefaan J Soenen, Bella B Manshian, Shareen H Doak, Kevin Braeckmans, Stefaan C De Smedt, Katrien Remaut
: In the last decade the interest in autophagy got an incredible boost and the phenomenon quickly turned into an extensive research field. Interestingly, dysfunction of this cytoplasmic clearance system has been proposed to lie at the root of multiple diseases including cancer. We therefore consider it crucial from a toxicological point of view to investigate if nanomaterials that are developed for biomedical applications interfere with this cellular process. Here, we study the highly promising 'gradient alloyed' quantum dots (QDs) that differ from conventional ones by their gradient core composition which allows for better fluorescent properties...
October 17, 2016: Acta Biomaterialia
William Joseph MacInnes
Cuing a location in space produces a short-lived advantage in reaction time to targets at that location. This early advantage, however, switches to a reaction time cost and has been termed inhibition of return (IOR). IOR behaves differently for different response modalities, suggesting that it may not be a unified effect. This letter presents new data from two experiments testing the gradient of IOR with random, continuous cue-target Euclidean distance and cue-target onset asynchrony. This data were then used to train multiple diffusion models of saccadic and manual reaction time for these cuing experiments...
October 20, 2016: Neural Computation
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"