keyword
MENU ▼
Read by QxMD icon Read
search

Tipping point

keyword
https://www.readbyqxmd.com/read/28438010/study-on-crystallographic-orientation-effect-on-surface-generation-of-aluminum-in-nano-cutting
#1
Feifei Xu, Fengzhou Fang, Yuanqing Zhu, Xiaodong Zhang
The material characteristics such as size effect are one of the most important factors that could not be neglected in cutting the material at nanoscale. The effects of anisotropic nature of single crystal materials in nano-cutting are investigated employing the molecular dynamics simulation. Results show that the size effect of the plastic deformation is based on different plastic carriers, such as the twin, stacking faults, and dislocations. The minimum uncut chip thickness is dependent on cutting direction, where even a negative value is obtained when the cutting direction is {110}<001>...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28436860/effect-on-high-intensity-fields-of-a-tough-hydrophone-with-hydrothermal-pzt-thick-film-vibrator-and-titanium-front-layer
#2
Nagaya Okada, Shinichi Takeuchi
A novel tough hydrophone was fabricated by depositing hydrothermally synthesized lead zirconate titanate polycrystalline film on the back-side surface of a titanium plate. Our developed tough hydrophone resisted damage in a high-pressure field (15 MPa) at a focal point of a sinusoidal continuous wave driven by a concave high-intensity focused ultrasound (HIFU) transducer with up to 50 W of power input to the sound source. The hydrophone was suitable for the HIFU field, even though the hydrophone has a flat-shape tip of 3...
April 24, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28435378/differentiating-spontaneous-vertical-root-fracture-in-endodontically-treated-tooth
#3
Myung-Jin Lim, Jung-Ae Kim, Yoorina Choi, Chan-Ui Hong, Kyung-San Min
Although vertical root fracture (VRF) is mostly found in endodontically treated teeth, it also occurs spontaneously. If VRF is recognized after endodontic treatment, it is considered to be iatrogenic and can lead to legal trouble. However, legal problems can be averted if the dentist can prove that the VRF existed before endodontic treatment. This case report describes an unusual, spontaneous VRF in an endodontically treated tooth and presents a useful tip for determining whether a fracture is iatrogenic. We performed nonsurgical endodontic treatment on a mandibular first molar with irreversible pulpitis...
January 2017: European Journal of Dentistry
https://www.readbyqxmd.com/read/28434449/electrical-superior-vena-cava-isolation-using-a-novel-pace-and-ablate-technique-under-diaphragmatic-electromyography-monitoring
#4
Shinsuke Miyazaki, Shigeki Kusa, Hitoshi Hachiya, Hiroshi Taniguchi, Takayuki Niida, Sadamitsu Ichijo, Kenzo Hirao, Yoshito Iesaka
BACKGROUND: Diaphragmatic compound motor action potential (CMAP) amplitude monitoring is a standard technique to anticipate phrenic nerve injury during cryoballoon ablation. OBJECTIVE: The purpose of this study was to evaluate the feasibility of a novel superior vena cava isolation (SVCI) technique using simultaneous pacing and ablation through the tip of a single mapping/ablation catheter. METHODS: Fifty-four patients with atrial fibrillation were included...
May 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28430914/finding-the-right-balance-androgens-at-the-tipping-point-of-fertility-and-metabolism-in-women
#5
Michael T Sellix, Aritro Sen
No abstract text is available yet for this article.
March 1, 2017: Endocrinology
https://www.readbyqxmd.com/read/28428744/mutational-analysis-at-intersubunit-interfaces-of-an-anionic-glutamate-receptor-reveals-a-key-interaction-important-for-channel-gating-by-ivermectin
#6
Nurit Degani-Katzav, Revital Gortler, Marina Weissman, Yoav Paas
The broad-spectrum anthelmintic drug ivermectin (IVM) activates and stabilizes an open-channel conformation of invertebrate chloride-selective glutamate receptors (GluClRs), thereby causing a continuous inflow of chloride ions and sustained membrane hyperpolarization. These effects suppress nervous impulses and vital physiological processes in parasitic nematodes. The GluClRs are pentamers. Homopentameric receptors assembled from the Caenorhabditis elegans (C. elegans) GluClα (GLC-1) subunit can inherently respond to IVM but not to glutamate (the neurotransmitter)...
2017: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/28425594/trilobed-pedicled-superior-gluteal-artery-perforator-flap-for-lumbosacral-defect-coverage
#7
Ji Min Kim, Jun Ho Lee, Deuk Young Oh, Suk-Ho Moon
BACKGROUND: There are many available options for the coverage of lumbosacral area defects. Surgeons usually use the superior gluteal artery perforator flap (SGAP) by rotational fashion, which risks complications, such as wound dehiscence or skin necrosis at the Y-point on the donor site due to the tension. In this report, the authors present the experience of using trilobed pedicled SGAP flaps in coverage of the lumbosacral area defects. METHODS: From 2011 to 2015, 16 trilobed pedicled SGAP flaps were performed for the coverage of sacral defects in our facility...
April 20, 2017: Microsurgery
https://www.readbyqxmd.com/read/28425030/hand-eye-calibration-for-surgical-cameras-a-procrustean-perspective-n-point-solution
#8
Isabella Morgan, Uditha Jayarathne, Adam Rankin, Terry M Peters, Elvis C S Chen
PURPOSE: Surgical cameras are prevalent in modern operating theatres often used as surrogates for direct vision. A surgical navigational system is a useful adjunct, but requires an accurate "hand-eye" calibration to determine the geometrical relationship between the surgical camera and tracking markers. METHODS: Using a tracked ball-tip stylus, we formulated hand-eye calibration as a Perspective-n-Point problem, which can be solved efficiently and accurately using as few as 15 measurements...
April 19, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28422778/ultrasound-as-a-screening-tool-for-central-venous-catheter-positioning-and-exclusion-of-pneumothorax
#9
Rabia Amir, Ziyad O Knio, Feroze Mahmood, Achikam Oren-Grinberg, Akiva Leibowitz, Ruma Bose, Shahzad Shaefi, John D Mitchell, Muneeb Ahmed, Amit Bardia, Daniel Talmor, Robina Matyal
OBJECTIVES: Although real-time ultrasound guidance during central venous catheter insertion has become a standard of care, postinsertion chest radiograph remains the gold standard to confirm central venous catheter tip position and rule out associated lung complications like pneumothorax. We hypothesize that a combination of transthoracic echocardiography and lung ultrasound is noninferior to chest radiograph when used to accurately assess central venous catheter positioning and screen for pneumothorax...
April 18, 2017: Critical Care Medicine
https://www.readbyqxmd.com/read/28421316/comparison-of-the-coracoid-and-retroclavicular-approaches-for-ultrasound-guided-infraclavicular-brachial-plexus-block
#10
Nilgun Kavrut Ozturk, Ali Sait Kavakli
PURPOSE: This prospective randomized study compared the coracoid and retroclavicular approaches to ultrasound-guided infraclavicular brachial plexus block (IBPB) in terms of needle tip and shaft visibility and quality of block. We hypothesized that the retroclavicular approach would increase needle tip and shaft visibility and decrease the number of needle passes compared to the coracoid approach. METHODS: A total of 100 adult patients who received IBPB block for upper limb surgery were randomized into two groups: a coracoid approach group (group C) and a retroclavicular approach group (group R)...
April 18, 2017: Journal of Anesthesia
https://www.readbyqxmd.com/read/28420980/loss-of-melanopsin-expressing-ganglion-cell-subtypes-and-dendritic-degeneration-in-the-aging-human-retina
#11
Gema Esquiva, Pedro Lax, Juan J Pérez-Santonja, José M García-Fernández, Nicolás Cuenca
In mammals, melanopsin-expressing retinal ganglion cells (mRGCs) are, among other things, involved in several non-image-forming visual functions, including light entrainment of circadian rhythms. Considering the profound impact of aging on visual function and ophthalmic diseases, here we evaluate changes in mRGCs throughout the life span in humans. In 24 post-mortem retinas from anonymous human donors aged 10-81 years, we assessed the distribution, number and morphology of mRGCs by immunostaining vertical retinal sections and whole-mount retinas with antibodies against melanopsin...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/28417957/attractive-force-driven-superhardening-of-graphene-membranes-as-a-pin-point-breaking-of-continuum-mechanics
#12
Makoto Ashino, Roland Wiesendanger
Bending at the nanometre scale can substantially modify the mechanical, chemical and electronic properties of graphene membranes. The subsequent response of chemical bonds leads to deviations from plate idealisation in continuum mechanics. However, those phenomena have thus far been investigated exclusively by measuring the electronic properties of graphene deformed by compressing and stretching with local-probe techniques. Here, we report that the interatomic-attractive forces applied on the convexly-curved graphene by the probe tip give rise to a pin-point breaking of the plate idealisation in the continuum mechanics, facilitating atomically-localised enhancements in its chemical reactivity and mechanical strength...
April 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28412980/arctic-systems-in-the-quaternary-ecological-collision-faunal-mosaics-and-the-consequences-of-a-wobbling-climate
#13
E P Hoberg, J A Cook, S J Agosta, W Boeger, K E Galbreath, S Laaksonen, S J Kutz, D R Brooks
Climate oscillations and episodic processes interact with evolution, ecology and biogeography to determine the structure and complex mosaic that is the biosphere. Parasites and parasite-host assemblages are key components in a general explanatory paradigm for global biodiversity. We explore faunal assembly in the context of Quaternary time frames of the past 2.6 million years, a period dominated by episodic shifts in climate. Climate drivers cross a continuum from geological to contemporary timescales and serve to determine the structure and distribution of complex biotas...
April 17, 2017: Journal of Helminthology
https://www.readbyqxmd.com/read/28405373/bioinspired-polymer-microstructures-for-directional-transport-of-oily-liquids
#14
C Plamadeala, F Hischen, R Friesenecker, R Wollhofen, J Jacak, G Buchberger, E Heiss, T A Klar, W Baumgartner, J Heitz
Nature has always served as an inspiration for scientists, helping them to solve a large diversity of technical problems. In our case, we are interested in the directional transport of oily liquids and as a model for this application we used the flat bug Dysodius lunatus. In this report, we present arrays of drops looking like polymer microstructures produced by the two-photon polymerization technique that mimic the micro-ornamentation from the bug's cuticle. A good directionality of oil transport was achieved, directly controlled by the direction of the pointed microstructures at the surface...
March 2017: Royal Society Open Science
https://www.readbyqxmd.com/read/28398291/fine-dissection-of-the-tarsal-tunnel-in-60-cases
#15
Y Yang, M L Du, Y S Fu, W Liu, Q Xu, X Chen, Y J Hao, Z Liu, M J Gao
The fine dissection of nerves and blood vessels in the tarsal tunnel is necessary for clinical operations to provide anatomical information. A total of 60 feet from 30 cadavers were dissected. Two imaginary reference lines that passed through the tip of the medial malleolus were applied. A detailed description of the branch pattern and the corresponding position of the posterior tibial nerve, posterior tibial artery, medial calcaneal nerve and medial calcaneal artery was provided, and the measured data were analyzed...
April 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28391062/robust-guidewire-tracking-under-large-deformations-combining-segment-like-features-seglets
#16
Alessandro Vandini, Ben Glocker, Mohamad Hamady, Guang-Zhong Yang
Robust tracking of interventional tools, such as guidewires and catheters, in X-ray fluoroscopic video sequences has a wide range of clinical applications for endovascular procedures. Thus far, the tracking is usually achieved by finding the optimal displacement of the control points of a spline, which models the guidewire, between consecutive frames. The displacement of the control points is typically driven by a data term and smoothed by a regularization term. In the presence of large deformation and changes in length of the tool, the current tracking methods may fail to recover the guidewire motion...
March 15, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28387448/an-adaptive-and-fully-automatic-method-for-estimating-the-3d-position-of-bendable-instruments-using-endoscopic-images
#17
Paolo Cabras, Florent Nageotte, Philippe Zanne, Christophe Doignon
BACKGROUND: Flexible bendable instruments are key tools for performing surgical endoscopy. Being able to measure the 3D position of such instruments can be useful for various tasks, such as controlling automatically robotized instruments and analyzing motions. METHODS: An automatic method is proposed to infer the 3D pose of a single bending section instrument, using only the images provided by a monocular camera embedded at the tip of the endoscope. The proposed method relies on colored markers attached onto the bending section...
April 7, 2017: International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS
https://www.readbyqxmd.com/read/28383023/demystifying-rotors-and-their-place-in-clinical-translation-of-atrial-fibrillation-mechanisms
#18
REVIEW
Stanley Nattel, Feng Xiong, Martin Aguilar
Treatment of atrial fibrillation (AF), the most common arrhythmia in clinical practice, remains challenging. Improved understanding of underlying mechanisms is needed to improve therapy. Functional re-entry is central to AF maintenance. The first detailed, quantitative theory of functional re-entry, the 'leading circle' model, was developed 40 years ago. Subsequently, an alternative paradigm based on 'spiral waves' has evolved. Spiral-wave generators, or 'rotors', have been identified using advanced mapping methods in experimental and clinical AF...
April 6, 2017: Nature Reviews. Cardiology
https://www.readbyqxmd.com/read/28382712/traser-an-innovative-device-for-the-treatment-of-nasal-telangiectasias
#19
Paul M Friedman, Stanislav N Tolkachjov, Elizabeth R Geddes, Karl A Tillman, Christopher B Zachary
BACKGROUND: Destruction of blood vessels by selective photothermolysis has been successfully achieved using a number of different laser and light systems, none of which provide significant independent variation in parameters such as wavelength. OBJECTIVE: To evaluate the safety and efficacy of a novel configurable device in the treatment of nasal telangiectasias. METHODS: Fifteen subjects aged 42-73 with Fitzpatrick skin types I and II were treated for nasal telangiectasias of various sizes...
April 6, 2017: Lasers in Surgery and Medicine
https://www.readbyqxmd.com/read/28379718/sonic-hedgehog-signaling-regulates-myofibroblast-function-during-alveolar-septum-formation-in-murine-postnatal-lung
#20
Matthias C Kugler, Cynthia A Loomis, Zhicheng Zhao, Jennifer C Cushman, Li Liu, John S Munger
Sonic Hedgehog (Shh) signaling regulates mesenchymal proliferation and differentiation during embryonic lung development. In the adult lung, Shh signaling maintains mesenchymal quiescence and is dysregulated in diseases such as IPF and COPD. Our previous data implicated a role for Shh in postnatal lung development. Here we report a detailed analysis of Shh signaling during murine postnatal lung development. We show that Shh pathway expression and activity during alveolarization (P0-P14) are distinct from those during maturation (P14-P24)...
April 5, 2017: American Journal of Respiratory Cell and Molecular Biology
keyword
keyword
81468
1
2
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"