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https://www.readbyqxmd.com/read/29329136/glaucoma-implant-tube-lumen-obstruction-visualized-using-anterior-segment-optical-coherence-tomography
#1
Shunsuke Nakakura, Asuka Noguchi, Santaro Noguchi, Yuka Hirose, Koji Niimi, Hitoshi Tabuchi, Yoshiaki Kiuchi
We report a case of glaucoma implant tube lumen obstruction visualized with anterior segment optical coherence tomography (ASOCT) and present its surgical management. The patient was a 66-year-old man with refractory glaucoma associated with traumatic aphakia in the right eye after trabeculectomy, several bleb needling procedures, and scleral fixation of the intraocular lens with pars plana vitrectomy. Finally, we performed Baerveldt implantation at the pars plana of the temporal inferior quadrant with a several Sherwood slit...
January 11, 2018: Journal of Glaucoma
https://www.readbyqxmd.com/read/29326235/predicting-tipping-points-in-complex-environmental-systems
#2
John C Moore
No abstract text is available yet for this article.
January 11, 2018: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29317353/the-sensory-equipment-of-a-spider-a-morphological-survey-of-different-sensilla-types-in-both-sexes-of-argiope-bruennichi-araneae-araneidae
#3
Anne-Sarah Ganske, Gabriele Uhl
Spiders show a wide range of sensory capabilities as evidenced by behavioural observations. Accordingly, spiders possess diverse sensory structures like mechano-, hygro-, thermo- or chemoreceptive sensilla. As to chemoreceptive structures, only trichoid tip-pore sensilla were found so far that were tested for gustation. That spiders are also able to receive airborne signals is corroborated by numerous behavioural experiments but the responsible structures have not been determined yet. Here, we provide sensilla distribution maps of pedipalps and walking legs of both sexes of the wasp spider Argiope bruennichi whose biology and mating system is well explored...
January 6, 2018: Arthropod Structure & Development
https://www.readbyqxmd.com/read/29316567/modern-invasive-hemodynamic-assessment-of-pulmonary-hypertension
#4
Alberto Pagnamenta, Frédéric Lador, Andrea Azzola, Maurice Beghetti
Since 1998 pulmonary hypertension has been clinically classified into five well-defined, distinct categories. A definitive diagnosis of pulmonary hypertension requires the invasive confirmation of an elevated mean pulmonary artery pressure of 25 mm Hg or above during a right heart catheterization. From a hemodynamic point of view, pulmonary hypertension is classified into precapillary and postcapillary pulmonary hypertension on the basis of a pulmonary artery wedge pressure threshold value of 15 mm Hg. Pulmonary vascular resistance is better characterized by multi-point pressure/flow measurements than by single-point determination...
January 9, 2018: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/29311325/predicting-tipping-points-in-mutualistic-networks-through-dimension-reduction
#5
Junjie Jiang, Zi-Gang Huang, Thomas P Seager, Wei Lin, Celso Grebogi, Alan Hastings, Ying-Cheng Lai
Complex networked systems ranging from ecosystems and the climate to economic, social, and infrastructure systems can exhibit a tipping point (a "point of no return") at which a total collapse of the system occurs. To understand the dynamical mechanism of a tipping point and to predict its occurrence as a system parameter varies are of uttermost importance, tasks that are hindered by the often extremely high dimensionality of the underlying system. Using complex mutualistic networks in ecology as a prototype class of systems, we carry out a dimension reduction process to arrive at an effective 2D system with the two dynamical variables corresponding to the average pollinator and plant abundances...
January 8, 2018: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29305735/anglenav-mems-tracker-to-facilitate-ct-guided-puncture
#6
Rui Li, Sheng Xu, William F Pritchard, John W Karanian, Venkatesh P Krishnasamy, Bradford J Wood, Zion Tsz Ho Tse
As a low-cost needle navigation system, AngleNav may be used to improve the accuracy, speed, and ease of CT-guided needle punctures. The AngleNav hardware includes a wireless device with a microelectromechanical (MEMS) tracker that can be attached to any standard needle. The physician defines the target, desired needle path and skin entry point on a CT slice image. The accuracy of AngleNav was first tested in a 3D-printed calibration platform in a benchtop setting. An abdominal phantom study was then performed in a CT scanner to validate the accuracy of the device's angular measurement...
January 5, 2018: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/29303916/what-robot-for-tomorrow-and-what-improvement-can-we-expect
#7
Benjamin Namdarian, Prokar Dasgupta
PURPOSE OF REVIEW: The purpose of this review is to summarize the status of robotic surgery currently, contextualizing the advances and improvements we can expect in the immediate future. Robotics continues to demonstrate increased utility and expansion in medicine, particularly surgery. When coupled with the imminent expiry of Intuitive patents in the next few years, it is timely to consider what we can expect to see from new platforms; what new features might we anticipate and what technology will be available to enhance and improve patient care...
January 4, 2018: Current Opinion in Urology
https://www.readbyqxmd.com/read/29295510/pollution-from-fossil-fuel-combustion-is-the-leading-environmental-threat-to-global-pediatric-health-and-equity-solutions-exist
#8
Frederica Perera
Fossil-fuel combustion by-products are the world's most significant threat to children's health and future and are major contributors to global inequality and environmental injustice. The emissions include a myriad of toxic air pollutants and carbon dioxide (CO₂), which is the most important human-produced climate-altering greenhouse gas. Synergies between air pollution and climate change can magnify the harm to children. Impacts include impairment of cognitive and behavioral development, respiratory illness, and other chronic diseases-all of which may be "seeded" in utero and affect health and functioning immediately and over the life course...
December 23, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/29291592/improving-sensitivity-of-a-miniaturized-label-free-electrochemical-biosensor-using-zigzag-electrodes
#9
Yi-Ching Kuo, Chih-Kung Lee, Chih-Ting Lin
Cardiovascular disease (CVD) is a leading cause of death among chronic diseases worldwide. Therefore, it is important to be able to detect CVD biomarkers early so that patients can be diagnosed properly and begin treatment as soon as possible. To detect biomarkers more conveniently, point-of-care (PoC) biosensors, which are easy to use and are of low cost, are becoming even more necessary. This paper focuses on developing a label-free electrochemical biosensor with high sensitivity for PoC applications to detect CVD biomarkers such as S100 beta proteins and C-reactive proteins (CRP)...
December 2, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/29291249/spatial-charge-inhomogeneity-and-defect-states-in-topological-dirac-semimetal-thin-films-of-na3bi
#10
Mark T Edmonds, James L Collins, Jack Hellerstedt, Indra Yudhistira, Lídia C Gomes, João N B Rodrigues, Shaffique Adam, Michael S Fuhrer
Topological Dirac semimetals (TDSs) are three-dimensional analogs of graphene, with carriers behaving like massless Dirac fermions in three dimensions. In graphene, substrate disorder drives fluctuations in Fermi energy, necessitating construction of heterostructures of graphene and hexagonal boron nitride (h-BN) to minimize the fluctuations. Three-dimensional TDSs obviate the substrate and should show reduced EF fluctuations due to better metallic screening and higher dielectric constants. We map the potential fluctuations in TDS Na3Bi using a scanning tunneling microscope...
December 2017: Science Advances
https://www.readbyqxmd.com/read/29286396/fabrication-of-fine-electrodes-on-the-tip-of-hypodermic-needle-using-photoresist-spray-coating-and-flexible-photomask-for-biomedical-applications
#11
Joho Yun, Jinhwan Kim, Jong-Hyun Lee
We have introduced a fabrication method for electrical impedance spectroscopy (EIS)-on-a-needle (EoN: EIS-on-a-needle) to locate target tissues in the body by measuring and analyzing differences in the electrical impedance between dissimilar biotissues. This paper describes the fabrication method of fine interdigitated electrodes (IDEs) at the tip of a hypodermic needle using a photoresist spray coating and flexible film photomask in the photolithography process. A polyethylene terephthalate (PET) heat shrink tube (HST) with a wall thickness of 25 µm is employed as the insulation and passivation layer...
November 28, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29285773/functional-architecture-of-the-somatosensory-homunculus-detected-by-electrostimulation
#12
Franck-Emmanuel Roux, Imène Djidjeli, Jean-Baptiste Durand
In this prospective electrostimulation study, based on 50 operated patients with no sensory deficit and no brain lesion in the postcentral gyrus, we acquired coordinates in the standard MNI space of the functional areas of the somatosensory homunculus. The 3D brain volume of each patient was normalized to that space to obtain the MNI coordinates of the stimulation site locations. For 647 sites stimulated on Brodmann Area 1 (and 1025 in gyri nearby), 258 positive points for somatosensory response (40%) were found in the postcentral gyrus...
December 29, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/29281147/homogenizing-an-urban-habitat-mosaic-arthropod-diversity-declines-in-new-york-city-parks-after-super-storm-sandy
#13
Amy M Savage, Elsa Youngsteadt, Andrew F Ernst, Shelby A Powers, Robert R Dunn, Steven D Frank
The frequency and intensity of hurricanes are increasing globally, and anthropogenic modifications in cities have created systems that may be particularly vulnerable to their negative effects. Organisms living in cities are exposed to variable levels of chronic environmental stress. However, whether chronic stress ameliorates or exacerbates the negative effects of hurricanes remains an open question. Here, we consider two hypotheses about the simultaneous consequences of acute disturbances from hurricanes and chronic stress from urbanization for the structure of urban arthropod communities...
December 27, 2017: Ecological Applications: a Publication of the Ecological Society of America
https://www.readbyqxmd.com/read/29279866/penetration-mechanics-of-a-beetle-intromittent-organ-with-bending-stiffness-gradient-and-a-soft-tip
#14
Yoko Matsumura, Alexander E Kovalev, Stanislav N Gorb
Hyper-elongated structures and their penetration are widespread among insects, for example, intromittent organs, ovipositors, and piercing-sucking mouthparts. The penetration of thin structures with high aspect ratio without buckling and rupturing is mechanically very challenging. However, this problem is economically solved in nature, and the solutions might be helpful for, for example, in the development of harmless catheters. We focus on the penetration process of a hyper-elongated structure of a cassidine beetle intromittent organ, termed a flagellum...
December 2017: Science Advances
https://www.readbyqxmd.com/read/29279767/3-dimensional-reconstruction-of-mandibular-canal-at-the-interforaminal-region-using-micro-computed-tomography-in-korean
#15
Yong Hyun Jeon, Chul Kwon Lee, Hee-Jung Kim, Jae-Heon Chung, Heung-Joong Kim, Sun-Kyoung Yu
PURPOSE: The purpose of this study was to identify the complex course of the mandibular canal using 3D reconstruction of microCT images and to provide the diagram for clinicians to help them understand at the interforaminal region in Korean. MATERIALS AND METHODS: Twenty-six hemimandibles obtained from cadavers were examined using microCT, and the images were reconstructed. At both the midpoint of mental foramen and the tip of anterior loop, the bucco-lingual position, the height from the mandibular inferior border, the horizontal distance between two points, and position relative to tooth site on the mandibular canal were measured...
December 2017: Journal of Advanced Prosthodontics
https://www.readbyqxmd.com/read/29277643/revealing-critical-mechanisms-of-br-mediated-apple-nursery-tree-growth-using-itraq-based-proteomic-analysis
#16
Liwei Zheng, Juanjuan Ma, Lizhi Zhang, Cai Gao, Dong Zhang, Caiping Zhao, Mingyu Han
Brassinosteroid is identified as an important hormone. However, information about brassinosteroid has not been fully elucidated, and few studies concerned its role in apple. The aim of this work was to study the role of brassinosteroid for apple tree growth. In our study, the effect of brassinosteroid on apple nursery tree was analyzed. The biomass, cell size and xylem content of apple nursery tree were obviously evaluated by brassinosteroid treatment; mineral elements contents, photosynthesis indexes, carbohydrate level and hormone contents were significantly high in brassinosteroid treated trees...
December 19, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/29276975/non-tip-auditory-nerve-responses-that-are-suppressed-by-low-frequency-bias-tones-originate-from-reticular-lamina-motion
#17
Hui Nam, John J Guinan
Recent cochlear mechanical measurements show that active processes increase the motion response of the reticular lamina (RL) at frequencies more than an octave below the local characteristic frequency (CF) for CFs above 5 kHz. A possible correlate is that in high-CF (>5 kHz) auditory-nerve (AN) fibers, responses to frequencies 1-3 octaves below CF ("tail" frequencies) can be inhibited by medial olivocochlear (MOC) efferents. These results indicate that active processes enhance the sensitivity of tail-frequency RL and AN responses...
December 14, 2017: Hearing Research
https://www.readbyqxmd.com/read/29275626/elucidation-of-excitation-energy-dependent-correlated-triplet-pair-formation-pathways-in-an-endothermic-singlet-fission-system
#18
Arya Thampi, Hannah Stern, Alexandre Cheminal, Murad J Y Tayebjee, Anthony J Petty Ii, John E Anthony, Akshay Rao
Singlet fission is the spin allowed conversion of a photo-generated singlet exciton into two triplet excitons in organic semiconductors, which could enable single-junction photovoltaic cells to break the Shockley-Queisser limit. The conversion of singlets to free triplets is mediated by an intermediate correlated triplet pair (TT) state, but an understanding of how the formation and dissociation of these states depend on energetics and morphology is lacking. In this study, we probe the dynamics of TT states in a model endothermic fission system, TIPS-Tc nanoparticles, which show a mixture of crystalline and disordered regions...
December 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29275161/aging-inflammation-and-the-environment
#19
REVIEW
Arsun Bektas, Shepherd H Schurman, Ranjan Sen, Luigi Ferrucci
The aging process is driven by interrelated mechanisms that lead to the emergence of characteristic phenotypes that include changes in body composition, energy production and utilization imbalance, homeostatic dysregulation, and neurodegeneration and loss of neuroplasticity. Mainstream theories of aging all recognize that the aging phenotypes result from an imbalance between stressors and stress buffering mechanisms and a resultant loss of compensatory reserve leading to accumulation of unrepaired damage. This in turn results in increased disease susceptibility, reduced functional reserve, reduced healing capacity and stress resistance, unstable health and finally failure to thrive...
December 21, 2017: Experimental Gerontology
https://www.readbyqxmd.com/read/29260731/four-point-probe-measurements-using-current-probes-with-voltage-feedback-to-measure-electric-potentials
#20
Felix Lüpke, David Cuma, Stefan Korte, Vasily Cherepanov, Bert Voigtlander
We present a four-point probe resistance measurement technique which uses four equivalent current measuring units, resulting in minimal hardware requirements and corresponding sources of noise. Local sample potentials are measured by a software feedback loop which adjusts the corresponding tip voltage such that no current flows to the sample. The resulting tip voltage is then equivalent to the sample potential at the tip position. We implement this measurement method into a multi-tip scanning tunneling microscope setup such that potentials can also be measured in tunneling contact, allowing in principle truly non-invasive four-probe measurements...
December 20, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
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