Read by QxMD icon Read

Surface Orientation

C P Moerland, L J van IJzendoorn, M W J Prins
Magnetic particles are widely used in lab-on-chip and biosensing applications, because they have a high surface-to-volume ratio, they can be actuated with magnetic fields and many biofunctionalization options are available. The most well-known actuation method is to apply a magnetic field gradient which generates a translational force on the particles and allows separation of the particles from a suspension. A more recently developed magnetic actuation method is to exert torque on magnetic particles by a rotating magnetic field...
February 20, 2019: Lab on a Chip
Norihiko Yokoi, Georgi As Georgiev
Tear-film (TF) stability protects the ocular surface epithelium from desiccation and is ensured via cooperation between the ocular surface components including constituents of the TF and ocular surface epithelium. Thus, when those components are insufficient or impaired, the TF breakup that initiates dry eye occurs. Recently, new, commercially available eye drops have appeared in Japan that enable TF stabilization via targeted supplementation of deficient ocular surface components. Hence, a new layer-by-layer diagnosis and treatment concept for dry eye, termed tear-film-oriented diagnosis and tear-film-oriented therapy (TFOD and TFOT, respectively), have emerged and become widely accepted in Asian countries and beyond...
February 19, 2019: Japanese Journal of Ophthalmology
Mahboubeh Dolatyari, Ali Jafari, Ali Rostami, Axel Klein
A novel type of transparent monitor with high-resolution images based on Si-SiO2 core-shell nanoparticles is presented in this contribution. In this monitor, a quasi-array of nanoparticles was used to obtain a very sharp scattering profile. For this purpose, the Si-SiO2 nanoparticles were synthesized and with controlling the size of particles, the dominant emission wavelength was controlled. For the fabrication of a blue color transparent monitor the solution processed Si-SiO2 nanoparticles were dispersed in polystyrene and then coated on a transparent glass surface...
February 19, 2019: Scientific Reports
Kamel El Omari, Sai Li, Abhay Kotecha, Thomas S Walter, Eduardo A Bignon, Karl Harlos, Pentti Somerharju, Felix De Haas, Daniel K Clare, Mika Molin, Felipe Hurtado, Mengqiu Li, Jonathan M Grimes, Dennis H Bamford, Nicole D Tischler, Juha T Huiskonen, David I Stuart, Elina Roine
Lipid membrane fusion is an essential function in many biological processes. Detailed mechanisms of membrane fusion and the protein structures involved have been mainly studied in eukaryotic systems, whereas very little is known about membrane fusion in prokaryotes. Haloarchaeal pleomorphic viruses (HRPVs) have a membrane envelope decorated with spikes that are presumed to be responsible for host attachment and membrane fusion. Here we determine atomic structures of the ectodomains of the 57-kDa spike protein VP5 from two related HRPVs revealing a previously unreported V-shaped fold...
February 19, 2019: Nature Communications
Chia-Cheng Yu, Yi-Wen Chen, Po-Ying Yeh, Yu-Sheng Hsiao, Wei-Ting Lin, Chiung-Wen Kuo, Di-Yen Chueh, Yun-Wen You, Jing-Jong Shyue, Ying-Chih Chang, Peilin Chen
BACKGROUND: Circulating tumor cells (CTCs) comprise the high metastatic potential population of cancer cells in the blood circulation of humans; they have become the established biomarkers for cancer diagnosis, individualized cancer therapy, and cancer development. Technologies for the isolation and recovery of CTCs can be powerful cancer diagnostic tools for liquid biopsies, allowing the identification of malignancies and guiding cancer treatments for precision medicine. METHODS: We have used an electrospinning process to prepare poly(lactic-co-glycolic acid) (PLGA) nanofibrous arrays in random or aligned orientations on glass slips...
February 19, 2019: Journal of Nanobiotechnology
Liang-Chia Chen, Thanh-Hung Nguyen
This paper presents a novel approach to the automated recognition and localization of 3-D objects. The proposed approach uses 3-D object segmentation to segment randomly stacked objects in an unstructured point cloud. Each segmented object is then represented by a regional area-based descriptor, which measures the distribution of surface area in the oriented bounding box (OBB) of the segmented object. By comparing the estimated descriptor with the template descriptors stored in the database, the object can be recognized...
February 13, 2019: Sensors
Wenyue Li, Nazifah Islam, Guofeng Ren, Shiqi Li, Zhaoyang Fan
There is strong interest in developing high-frequency (HF) supercapacitors or electrochemical capacitors (ECs), which can work at the hundreds to kilo hertz range for line-frequency alternating current (AC) filtering in the substitution of bulky aluminum electrolytic capacitors, with broad applications in the power and electronic fields. Although great progress has been achieved in the studies of electrode materials for ECs, most of them are not suitable to work in this high frequency range because of the slow electrochemical processes involved...
February 18, 2019: Materials
Anyang Cui, Peter De Wolf, Yan Ye, Zhigao Hu, Antoine Dujardin, Zhuangqun Huang, Kai Jiang, Liyan Shang, Ming Ye, Hao Sun, Junhao Chu
For assisting the in-depth investigations of widespread electromechanical phenomena in functional materials, piezoresponse force microscopy (PFM) has gradually evolved to realize full information-flow acquisition and fit the conductive liquid working environments. Here, we designed data cube (DCUBE) based PFM to collect the electromechanical effect into a high-dimensional array of piezoresponse by adding \emph{ac} bias with a wide range of frequencies to the probe. The electromechanical and mechanical spectra can be consecutively extracted at each pixel in the intermittent-contact mode...
February 19, 2019: Nanotechnology
Mi-Mi Dong, Zi-Qun Wang, Guang-Ping Zhang, Chuan-Kui Wang, Xiao-Xiao Fu
Modulating the electronic and magnetic properties of phosphorene is important for fabricating multi-functional electronic and spintronic devices. Employing density functional theory combined with the non-equilibrium Green's function, we systematically investigate the electronic, magnetic and transport properties of hydrogenated armchair phosphorene nanoribbons chemically modified by 3d transition metal atoms (Sc, Ti, V, Cr, Mn, Fe, Co and Ni). With chemical adsorption of transition metal atoms, the phosphorene nanoribbons exhibit excellent spin-polarized transport properties...
February 19, 2019: Physical Chemistry Chemical Physics: PCCP
Nikolay Zaitsev, Ralf Tonner, Ilya A Nechaev
We present an ab initio study of interfaces formed by placing a single trilayer of BiTeI on the Au(111) surface. We consider two possible interfaces with the parallel and antiparallel orientation of the trilayer dipole moment with respect to the surface normal, i.e., Te-Bi-I/Au(111) and I-Bi-Te/Au(111). We show that the resulting interface state that originates from the modified spin-orbit split surface state of the clean Au(111) surface resides at high energy above the Fermi level and acquires a large spin-splitting and reversal helicity as compared with the original surface state...
February 18, 2019: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Martin Brodrecht, Bharti Kumari, Sofia Lilly Thankamony, Hergen Breitzke, Torsten Gutmann, Gerd Buntkowsky
The structure and surface functionalization of biologically relevant silica-based hybrid materials is investigated by 2D solid-state NMR techniques combined with dynamic nuclear polarization (DNP). This approach is applied to a model system of mesoporous silica, which is modified by in pore grafting of small peptides via solid phase peptide synthesis (SPPS). To prove the covalent binding of the peptides on the surface, DNP enhanced solid-state NMR is used for the detection of 15N NMR signals in natural abundance...
February 18, 2019: Chemistry: a European Journal
Nicholas J Kaiser, Rajeev J Kant, Alicia J Minor, Kareen L K Coulombe
Natural polymer hydrogels are used ubiquitously as scaffold materials for cardiac tissue engineering as well as for soft tissue engineering more broadly because of FDA approval, minimal immunogenicity, and well-defined physiological clearance pathways. However, the relationships between natural polymer hydrogels and resident cell populations in directing the development of engineered tissues are poorly defined. This interaction is of particular concern for tissues prepared with iPSC-derived cell populations, in which population purity and batch-to-batch variability become additional critical factors to consider...
February 11, 2019: ACS Biomaterials Science & Engineering
Bernhard Hesse, Deborah Stier, Marine Cotte, Jean-Baptiste Forien, Paul Zaslansky
For biomedical research, successful imaging of calcified microstructures often relies on absorption differences between features, or on employing dies with selective affinity to areas of interest. When texture is concerned, e.g. for crystal orientation studies, polarization induced contrast is of particular interest. This requires sufficient interaction of the incoming radiation with the volume of interest in the sample to produce orientation-based contrast. Here we demonstrate polarization induced contrast at the calcium K-edge using submicron sized monochromatic synchrotron X-ray beams...
January 1, 2019: Biomedical Optics Express
Giacomo Lovat, Evan A Doud, Deyu Lu, Gregor Kladnik, Michael S Inkpen, Michael L Steigerwald, Dean Cvetko, Mark S Hybertsen, Alberto Morgante, Xavier Roy, Latha Venkataraman
N-heterocyclic carbenes (NHCs) bind very strongly to transition metals due to their unique electronic structure featuring a divalent carbon atom with a lone pair in a highly directional sp2 -hybridized orbital. As such, they can be assembled into monolayers on metal surfaces that have enhanced stability compared to their thiol-based counterparts. The utility of NHCs to form such robust self-assembled monolayers (SAMs) was only recently recognized and many fundamental questions remain. Here we investigate the structure and geometry of a series of NHCs on Au(111) using high-resolution X-ray photoelectron spectroscopy and density functional theory calculations...
January 21, 2019: Chemical Science
Ken Yong, Daniel Yuen, Moore Zhe Chen, Christopher J H Porter, Angus P R Johnston
Protein-conjugated nanoparticles have the potential to precisely deliver therapeutics to target sites in the body by specifically binding to cell surface receptors. To maximize targeting efficiency, the three-dimensional presentation of ligands towards these receptors is crucial. Herein, we demonstrate significantly enhanced targeting of nanoparticles to cancer cells by controlling the protein orientation on the nanoparticle surface. To engineer the point of attachment, we used amber codon reassignment to incorporate a synthetic amino acid, p-azidophenylalanine (azPhe), at specific locations within a single domain antibody (sdAb or nanobody) that recognizes the human epidermal growth factor receptor (EGFR)...
February 18, 2019: Nano Letters
Artur Zielinski, Mateusz Cieslik, Michal Sobaszek, Robert Bogdanowicz, Kazimierz Darowicki, Jacek Ryl
In this paper, we describe the modification of Nanoscale Impedance Microscopy (NIM), namely, a combination of contact-mode atomic force microscopy with local impedance measurements. The postulated approach is based on the application of multifrequency voltage perturbation instead of standard frequency-by-frequency analysis, which among others offers more time-efficient and accurate determination of the resultant impedance spectra with high spatial resolution. Based on the impedance spectra analysis with an appropriate electric equivalent circuit, it was possible to map surface resistance and contact capacitance...
February 8, 2019: Ultramicroscopy
Hong-Yan Chen, Mi-Xue Jin, Lu Zhang, Ai-Jun Wang, Junhua Yuan, Qian-Li Zhang, Jiu-Ju Feng
Recently, two-dimensional materials have gained increasing research attention due to their large surface area, high physical and chemical stability, and excellent electrocatalytic performances. Herein, we reported a simple and fast one-pot aqueous method for synthesis of two-dimensional porous bimetallic PtPd alloyed nanosheets (NSs) using benzyldimethylhexadecylammonium chloride (HDBAC) as the capping agent and stabilizer. The formation mechanism involved the oriented attachment and self-assembly. The PtPd NSs exhibited excellent oxygen reduction reaction (ORR) activity with the positive shift (c...
January 29, 2019: Journal of Colloid and Interface Science
Diandra de Andrades, Natália G Graebin, Marina Kimiko Kadowaki, Marco A Z Ayub, Roberto Fernandez-Lafuente, Rafael C Rodrigues
Three β-glucosidases (Pectinex Ultra SP-L, Pectinex Ultra Clear and homemade preparation from Aspergillus niger) were immobilized using different strategies: ionic adsorption on aminated (MANAE)-agarose beads at pH 5, 7, and 9, followed by biocatalysts modification with glutaraldehyde, or on glutaraldehyde pre-activated supports. The pH of the immobilization was altered to allow different enzyme molecule orientations on the support surface. The biocatalysts from Pectinex Ultra SP-L showed the highest thermal and operational stabilities when immobilized on MANAE-agarose-glutaraldehyde at pH 7...
February 14, 2019: International Journal of Biological Macromolecules
Xin Fu, Haynes Goddard, Xinhao Wang, Matthew E Hopton
Using combined sewer systems to handle excess stormwater runoff is common in older urban areas. Combined sewer overflow (CSO) events occur when hydraulic capacity is exceeded, and untreated wastewater discharges to surface waters. As urban population density increases, and more demand is placed on infrastructure, CSO events happen more often and cause serious environmental problems and public-health risks. Recently, green infrastructure (GI) has been integrated with existing gray infrastructure (GrayI) to reduce CSO events...
February 13, 2019: Journal of Environmental Management
Giulio Casali, Daniel Bush, Kate Jeffery
Entorhinal grid cells integrate sensory and self-motion inputs to provide a spatial metric of a characteristic scale. One function of this metric may be to help localize the firing fields of hippocampal place cells during formation and use of the hippocampal spatial representation ("cognitive map"). Of theoretical importance is the question of how this metric, and the resulting map, is configured in 3D space. We find here that when the body plane is vertical as rats climb a wall, grid cells produce stable, almost-circular grid-cell firing fields...
February 15, 2019: Proceedings of the National Academy of Sciences of the United States of America
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"