169 research outputs found
Significantly high polarization degree of the very low-albedo asteroid (152679) 1998 KU
We present a unique and significant polarimetric result regarding the
near-Earth asteroid (152679) 1998 KU , which has a very low
geometric albedo. From our observations, we find that the linear polarization
degrees of 1998 KU are 44.6 0.5\% in the R band
and 44.0 0.6\% in the V band at a solar phase angle of 81.0\degr. These
values are the highest of any known airless body in the solar system (i.e.,
high-polarization comets, asteroids, and planetary satellites) at similar phase
angles. This polarimetric observation is not only the first for primitive
asteroids at large phase angles, but also for low-albedo (< 0.1) airless
bodies.
Based on spectroscopic similarities and polarimetric measurements of
materials that have been sorted by size in previous studies, we conjecture that
1998 KU has a highly microporous regolith structure comprising
nano-sized carbon grains on the surface.Comment: 9 pages, 5 figures, and 3 tables, accepted for publication in A&
Negative modulation of beta3-adrenergic stimulation on cardiomyocyte contractile performance and [Ca2+]i regulation before and after heart failure: insights into the underlying cellular mechanisms
Preoperative and Postoperative Pulmonary Function in Elderly Patients with Thoracolumbar Kyphoscoliosis
Study DesignCase series.PurposeThe objective of this study was to investigate the change in pulmonary function in adult patients with a spinal deformity who underwent spinal corrective surgery.Overview of LiteratureDegenerative lumbar and/or thoraco-lumbar deformities are is often prominent in adult spinal deformity cases, whereas a thoracic deformity involving the chest wall is inconspicuous. A lumbar spine deformity could affect the pulmonary function; however, few reports have investigated pulmonary function in adult patients with a spinal deformity.MethodsThis study included 14 adult patients with a spinal deformity who underwent posterior corrective fusion (3 males, 11 females; mean age, 67.4 years). We measured percent vital capacity (%VC) and percent forced expiratory volume in 1 second (%FEV1) before surgery and six months after surgery. We investigated the change in pulmonary function after corrective surgery and the correlation between radiographic parameters and pulmonary function.ResultsMean preoperative %VC and %FEV1 values were 99.9% and 79.3%, respectively. Two cases were diagnosed with restrictive impairment, and two cases were diagnosed with obstructive impairment before surgery. %VC improved in the restrictive impairment cases six months after surgery. However, %FEV1 did not improve significantly after surgery in the obstructive impairment cases.ConclusionsRestrictive impairment was improved in adult patients with a spinal deformity by corrective spinal surgery. However, spinal surgery did not improve obstructive impairment
Response to: Hypoglossal Nerve Unjury after Cervical Spine Surgery
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens
1073-143 Physiological assessment of coronary artery stenosis using transthoracic doppler echocardiography at rest: Comparison of flow velocity pattern analysis with exercise thallium SPECT
Novel Measurement Technique for the Sagittal Vertical Axis and Its Clinical Application in Adult Spinal Deformity
Study DesignProspective physical measurement of the sagittal vertical axis (SVA).PurposeTo evaluate a simple method for measuring SVA by analyzing its relationship with radiographic measurements and clinical appearance.Overview of LiteratureNo studies have examined physical measurements using the cranial center of gravity (CCG) in a relaxed standing position.MethodsThe physical measurement of the horizontal distance between CCG and spina iliaca posterior superior (CCG-SIPS) was measured using a straight ruler in 252 healthy volunteers and 56 patients with adult spinal deformity. Health-related quality of life (HRQOL) was evaluated using the Oswestry disability index (ODI), and clinical symptoms were assessed according to standing status and the presence of gastroesophageal reflux disease (GERD).ResultsCCG-SIPS increased with age in the volunteer group and strongly correlated with radiographic SVA in the patient group (r=0.984). Differences increased between CCG-SIPS in patients in the relaxed position and radiographic SVA with an increase in sagittal malalignment (r=0.692, p120 mm) was significantly larger in the patient group than in the group with low sagittal malalignment (59.9±18.8 vs. 45.1±17.0; p=0.004); these patients (CCG-SIPS>120 mm) needed crutches or walkers for standing. The patient group with GERD had significantly larger sagittal malalignment than the group without GERD (160.3 mm vs. 81.0 mm).ConclusionsThe CCG-SIPS correlated with age and strongly reflected radiographic SVA and HRQOL in the patients. Moreover, it reflects a relaxed posture without a backward shift in the radiographic position even in patients with severe sagittal malalignment. The critical limit of CCG-SIPS can be relevant to clinical appearance, including standing assistance (>120 mm) and the existence of GERD (>150 mm). Thus, it will be a useful predictor of true SVA in clinical practice before radiographic evaluation
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