Read by QxMD icon Read


Sang Soo Eun, Sang-Ho Lee, H Yener Erken
No abstract text is available yet for this article.
December 14, 2017: Journal of Neurological Surgery. Part A, Central European Neurosurgery
Yu Jeong Choi, Ki-Woon Kang, Sang Hyun Jang, Jae Guk Kim, Soo Joo Lee, Kyung Tea Jung
Background/Aims: The induction and recurrence of syncope is a concerning situation that could be unpredicted in the vasovagal syncope (VVS). We investigated a simple predictor for the induced and recurrent VVS during Head-Up table-tilt Test (HUT) and clinically follow-up. Methods: The 143 consecutive patients with VVS (age 31 ± 19 years, 33 male) who referred by a cardiologist or neurologist and had undergone an echocardiogram, HUT, and a treadmill exercise test (TMT) were recruited and clinically follow-up...
December 18, 2017: Korean Journal of Internal Medicine
Jani Pirinen, Markku Walamies
INTRODUCTION: The tilt table test is used for determining the loss of consciousness, and in the case of reflex syncope, for gaining insight into the circulatory mechanism. In 2015, all tilt tests within the Hospital District of Helsinki and Uusimaa (HUS) were performed in the clinical physiology unit of the HUS Medical Imaging Center at Peijas Hospital. METHODS: The patients' medical history, circulation monitor printouts, and medical reports were recorded from all tilt tests carried out during 2015...
2017: Duodecim; Lääketieteellinen Aikakauskirja
Dingnan Deng, Weijuan Qu, Wenqi He, Yu Wu, Xiaoli Liu, Xiang Peng
We present a simple and effective compensation method for the off-axis tilt in common-path digital holographic microscopy (CPDHM) by introducing a rotating operation on the hologram. The proposed method mainly requires a digital reference hologram (DRH), which is a rotated version of the original one; it is assumed to be easy to obtain by rotating the specimen's hologram 180°. In this way, the off-axis tilt could be removed by subtracting the retrieved phase of DRH from the retrieved phase of the original hologram, but without any complex spectrum centering judgment, fitting procedures, or prior knowledge of the system...
December 15, 2017: Optics Letters
Andreas Ioannou, Antreas Theodosiou, Christophe Caucheteur, Kyriacos Kalli
In this Letter, we report a flexible, plane-by-plane direct write inscription method for the development of tailored, tilted fiber Bragg gratings using a femtosecond laser. Compared to ultraviolet or femtosecond laser inscription based on the phase mask, interferometric, or point-by-point methods, the presented approach is far more flexible and offers several advantages. Laser inscription is made through the fiber coating, while the grating planes are controlled to minimize birefringence, with precise control over the wavelength location and strength of cladding modes...
December 15, 2017: Optics Letters
Pascal Berto, Hervé Rigneault, Marc Guillon
We propose and implement a broadband, compact, and low-cost wavefront sensing scheme by simply placing a thin diffuser in the close vicinity of a camera. The local wavefront gradient is determined from the local translation of the speckle pattern. The translation vector map is computed thanks to a fast diffeomorphic image registration algorithm and integrated to reconstruct the wavefront profile. The simple translation of speckle grains under local wavefront tip/tilt is ensured by the so-called "memory effect" of the diffuser...
December 15, 2017: Optics Letters
S Longhi
Light refraction, i.e., the bending of the path of a light wave at the interface between two different dielectric media, is ubiquitous in optics. Refraction arises from the different speeds of light and is unavoidable in continuous media, according to Snell's Law. Here we show rather counterintuitively that omnidirectional refractionless propagation can be observed for discretized light crossing a tilted interface separating two homogeneous waveguide lattices.
December 15, 2017: Optics Letters
Wei Jin, Di-Hu Chen, Zhi-Wei Li, Hai-Yan Luo, Jin Hong
Spatial heterodyne spectroscopy (SHS) is a new spatial interference spectroscopy which can achieve high spectral resolution. The alignment error of the detector array can lead to a significant influence with the spectral resolution of a SHS system. Theoretical models for analyzing the alignment errors which are divided into three kinds are presented in this paper. Based on these models, the tolerance angle of these errors has been given, respectively. The result of simulation experiments shows that when the angle of slope error, tilt error, and rotation error are less than 1...
December 10, 2017: Applied Optics
Hassan A Elagha
In this work, a new classical principle that can explain the refraction of a single photon path at the boundary between two different media is proposed. This principle leads to the two well-known laws of refraction and also to a simple linear form of Snell's law. This linear form not only played a vital role in simplifying the mathematics of analytical ray tracing, but also led to a unified common form for the meridional ray-tracing formulas. Also, it works as a basic rule for a new graphical ray-tracing technique...
December 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Psang Dain Lin, R Barry Johnson
Risley systems and tilting orthogonal double-prism systems are optical systems consisting of two prisms in series. The analysis of such systems typically involves both direct and inverse problems. Problems of the former type can be easily solved using ray-tracing equations. However, inverse problems are comparatively more difficult if the search direction is not properly given prior to iteration. In the present study, the two optical systems are modeled using the homogeneous coordinate notation. A method is then proposed for solving the direct and inverse problems of both optical systems using a ray-tracing approach and the first- and second-order derivative matrices of the skew rays...
December 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Liu Yang, Jin Wei Qi, Zhu Bin
A theoretical development is presented in this paper for describing and understanding the imaging and aberrations of a general form surface. The development is based on the Taylor expansion of an arbitrary ray trace from the object reference plane to the image reference plane, which is called the base mapping of the general form surface in this paper. The base mapping is expressed as two Taylor series of the object and pupil coordinates and the imaging and aberration coefficients in the third-order scope are derived and presented as analytical expressions relevant to the optic parameters, invoking no approximations...
December 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Andrew Williams, Quinn Boser, Animesh Singh Kumawat, Kshitij Agarwal, Hossein Rouhani, Albert Vette
Methods that effectively assess and train dynamic seated balance are critical for enhancing functional independence and reducing risk of secondary health complications in the elderly and individuals with neuromuscular impairments. The objective of this research was to devise and validate a portable tool for assessing and training dynamic seated balance. An instrumented wobble board was designed and constructed that: (1) elicits multidirectional perturbations in seated individuals; (2) quantifies seated balance proficiency; and (3) provides real-time, kinematics-based vibrotactile feedback...
December 13, 2017: Journal of Biomechanical Engineering
Yuewei Wang, Xiaomei Guan, Haofu Wang
Common obstacles to successful retrieval of retrievable inferior vena cave filter include embedded filter hook and severe tilt of the filter. We described a modified wire-loop snare technique using self-made fishhook-like pigtail catheter and 11-F-long sheath to retrieve a severe tilted filter with embedded hook successfully. The modified wire-loop snare technique is simple and effective requiring only standard equipment and single venous access. This technique may be suitable for some types of retrievable filter with embedded hook...
2017: SAGE Open Medical Case Reports
Beatrice De Maria, Vlasta Bari, Marco Ranucci, Valeria Pistuddi, Giovanni Ranuzzi, Anielle C M Takahashi, Aparecida M Catai, Laura Dalla Vecchia, Sergio Cerutti, Alberto Porta
Cardiac baroreflex (cBR) is activated by both arterial pressure (AP) increases and decreases. Sequence method, a widely utilized tool assessing cBR sensitivity (cBRS) from spontaneous heart period (HP) and systolic AP (SAP) variations, allows the separated computation of cBRS from positive and negative SAP variations. The recently proposed phase-rectified signal averaging (PRSA) method has the same feature but it has been applied so far solely to positive SAP variations. We adapted the PRSA method to compute cBRS over negative SAP variations and we compared the results with those derived from sequence method over two protocols: (i) graded head-up tilt (HUT) at 15, 30, 45, 60, and 75° in 19 healthy subjects and (ii) general anesthesia induction in 118 patients undergoing coronary artery bypass graft surgery...
December 13, 2017: Medical & Biological Engineering & Computing
Assem A Sultan, Anton Khlopas, Nicolas S Piuzzi, Morad Chughtai, Nipun Sodhi, Michael A Mont
BACKGROUND: In this review, we (1) evaluated the effect of adult spine deformity (ASD) and its surgical correction on patients who had a total hip arthroplasty (THA); (2) evaluated the outcomes of THA in patients who have had previous spinal fusion; and (3) we presented an algorithm on how to surgically address patients who simultaneously require THA and ASD correction. METHODS: A comprehensive literature search was conducted. Our final analysis included 14 studies...
November 22, 2017: Journal of Arthroplasty
Maike Reul, Harm Hoekstra
Background The posterior tibial plateau is often affected in intra-articular tibial fractures. Moreover, treating these posterior fractures is recognised as an important prognostic factor. Open reduction and internal fixation of lateral and posterior two column tibial plateau fractures can be achieved via a combined reversed L-shape approach and an anterolateral approach in the floating position without intraoperative repositioning of the patient. Material and Methods The operative procedure starts in the posterior position with visualisation of the posterior column after lateral retraction of the medial head of the M...
December 2017: Zeitschrift Für Orthopädie und Unfallchirurgie
Bozho Todorich, Maxwell S Stem, Keshav Kooragayala, Aristomenis Thanos, Lisa J Faia, George A Williams, Tarek S Hassan, Maria A Woodward, Jeremy D Wolfe
PURPOSE: To describe surgical outcomes and structural characteristics of intraocular lenses (IOLs) implanted with transconjunctival sutureless intrascleral (SIS) fixation in human eyes. DESIGN: Retrospective interventional surgical case series involving live and cadaveric human eyes. METHODS: In this study, we investigated the surgical outcomes and structural anatomy of secondary IOLs implanted with the SIS technique in human eyes. All cases involving SIS IOL fixation performed at a single academic center from January 1, 2012, through July 30, 2016, were reviewed to describe the surgical technique, common indications, clinical outcomes, and the rate of common operative complications...
December 11, 2017: Retina
Pontus Nordenfelt, Travis I Moore, Shalin B Mehta, Joseph Mathew Kalappurakkal, Vinay Swaminathan, Nobuyasu Koga, Talley J Lambert, David Baker, Jennifer C Waters, Rudolf Oldenbourg, Tomomi Tani, Satyajit Mayor, Clare M Waterman, Timothy A Springer
Integrin αβ heterodimer cell surface receptors mediate adhesive interactions that provide traction for cell migration. Here, we test whether the integrin, when engaged to an extracellular ligand and the cytoskeleton, adopts a specific orientation dictated by the direction of actin flow on the surface of migrating cells. We insert GFP into the rigid, ligand-binding head of the integrin, model with Rosetta the orientation of GFP and its transition dipole relative to the integrin head, and measure orientation with fluorescence polarization microscopy...
December 11, 2017: Nature Communications
Brian E Lee, Richard J Van Allan, Marc L Friedman, H Gabriel Lipshutz
BACKGROUND: The purpose of this study was to retrospectively assess the retrieval characteristics and rate of filter-related complications associated with use of the Celect Platinum (Cook Medical, Bloomington, Ind) inferior vena cava filter (IVCF). METHODS: A single-center, retrospective review was conducted to identify patients who received a Celect Platinum IVCF between June 2013 and February 2016. The patients' charts and imaging records (computed tomography [CT] and cavography) associated with filter placement, follow-up, and filter retrieval procedures were assessed for attempted and successful retrieval rates and filter-related complications...
December 8, 2017: Journal of Vascular Surgery. Venous and Lymphatic Disorders
Themistocles S Protopsaltis, Subaraman Ramchandran, Kojo Hamilton, Daniel Sciubba, Peter G Passias, Virginie Lafage, Renaud Lafage, Justin S Smith, Robert A Hart, Munish Gupta, Doug Burton, Shay Bess, Christopher Shaffrey, Christopher P Ames
STUDY DESIGN: Prospective multi-center cohort study with consecutive enrollment OBJECTIVE.: To evaluate pre-operative alignment and surgical factors associated with sub-optimal early post-operative radiographic outcomes following surgery for cervical deformity. SUMMARY OF BACKGROUND DATA: Recent studies have demonstrated correlation between cervical sagittal alignment and patient reported outcomes. Few studies have explored cervical deformity correction prospectively, and the factors that result in successful vs...
December 8, 2017: Spine
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"