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Direct numerical simulations are performed to investigate the characteristics of a turbulent core-annular flow with water-lubricated high viscosity oil in a horizontal pipe. Six different superficial velocity ratios (jw/jo = 0.057-0.41) are examined by changing the water superficial velocity jw for a fixed oil superficial velocity jo. The pressure drops in the pipe and the shapes of the phase interface agree well with those from previous experiments. The oil core flow is almost a plug flow, and the gaps between the phase interface and pipe wall are narrow and wide near the upper and lower surfaces of the pipe, respectively, due to the buoyancy. Within a narrow gap, water is confined mostly in a valley region of the wavy phase interface and hardly goes through its crest. On the other hand, water near the phase interface at a wide gap convects downstream almost at the core speed and the flow near the wall is similar to that of single-phase wall-bounded turbulent flow. The annular flow is characterized by three different regimes depending on the clearance Reynolds number (Rec) based on the core velocity and local gap size: laminar Couette flow driven by the core for Rec = 600, transitional flow for 600 < Rec < 2500 and turbulent flow for Rec = 2500. The minimum pressure drop occurs at jw/jo = 0.11 in the early transition regime. For all jw/jo considered, the negative lift force acting on the core comes from the pressure force which balances the buoyancy. [ABSTRACT FROM AUTHOR]

TAR DNA-binding protein 43 (TDP-43) is a member of an evolutionarily conserved family of heterogeneous nuclear ribonucleoproteins that modulate multiple steps in RNA metabolic processes. Cytoplasmic aggregation of TDP-43 in affected neurons is a pathological hallmark of many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), Alzheimer’s disease (AD), and limbic predominant age-related TDP-43 encephalopathy (LATE). Mislocalized and accumulated TDP-43 in the cytoplasm induces mitochondrial dysfunction and reactive oxidative species (ROS) production. Here, we show that TDP-43- and rotenone-induced neurotoxicity in the human neuronal cell line SH-SY5Y were attenuated by hydroxocobalamin (Hb, vitamin B12 analog) treatment. Although Hb did not affect the cytoplasmic accumulation of TDP-43, Hb attenuated TDP-43-induced toxicity by reducing oxidative stress and mitochondrial dysfunction. Moreover, a shortened lifespan and motility defects in TDP-43-expressing Drosophila were significantly mitigated by dietary treatment with hydroxocobalamin. Taken together, these findings suggest that oral intake of hydroxocobalamin may be a potential therapeutic intervention for TDP-43-associated proteinopathies. [ABSTRACT FROM AUTHOR]

Neuroretinitis is a rare clinical entity, characterized by optic nerve edema and star-shape hard exudate around fovea. The clinical features include acute unilateral visual loss, dyschromatopsia, relative afferent pupillary defect and visual field abnormalities. Increased vascular permeability of the optic disc is the main pathophysiology. As it is a not fully known clinical entity, diagnosis is challenging. In this case, we use multimodal imaging to reveal pathophysiology and anatomical change of early mild neuroretinitis. Case presentation: A 28-year-old healthy woman presented to the clinic with mild blurred vision in her left eye. After complete ophthalmic examination, outer retinal thickening of the temporal peripapillary area and optic disc edema were observed. Two days after diagnosis, the retinal edema and visual symptoms were aggravated. A hard exudate, maybe a part of macular star, was observed. Multimodal imaging including optical coherence tomography (OCT), swept-source OCT angiography (SS-OCTA), fluorescein angiography, and indocyanine green angiography visualized choroidal thinning and insufficient circulation beneath the outer retinal edema. Following steroid pulse therapy, the retinal edema and blurred vision were completely resolved. Conclusions: Multimodal imaging suggested that unilateral optic disc edema and early macular star help the diagnosis of neuroretinitis. In SS-OCTA, we found focal choroidal insufficiency. The focal insufficient choroidal circulation might be a contribution factor for idiopathic neuroretinitis. Multimodal imaging including SS-OCTA may be a valuable tool for detecting and monitoring disease progression. [ABSTRACT FROM AUTHOR]

Transfemoral cerebral angiography (TFCA) has been increasingly used as diagnostic method for the evaluation of cerebral vessels. Ophthalmologic complication after TFCA has rarely been reported, and most complications are associated with an intraoperative thrombo-embolic event. We reported a patient who developed a superior altitudinal visual field defect one day after diagnostic TFCA. The ophthalmic exam revealed a prominent inferior optic disc edema, and the fluorescein angiographic showed the non-perfusion of the corresponding inferior sectoral optic disc. Diffusionweighted MRI on the day following cerebral angiography revealed multiple focal scattered acute infarctions. Even one month after steroid pulse therapy, the superior nasal field defect remained with minimal improvement. We believe this case was consistent with an acute anterior ischemic optic neuropathy (AION) due to thrombo-embolism after TFCA. Ophthalmic examinations and a visual field test should be performed before and immediately after the TFCA, particularly in the case with a high risk of thromboembolic events. [ABSTRACT FROM AUTHOR]

Salt sensitivity of blood pressure is characterized by inappropriate sympathoexcitation and renal Na+ reabsorption during high salt intake. In salt-resistant animal models, exogenous norepinephrine (NE) infusion promotes salt-sensitive hypertension and prevents dietary Na+- evoked suppression of the Na' -Cl cotransporter (NCC). Studies of the adrenergic signaling pathways that modulate NCC activity during NE infusion have yielded conflicting results implicating α1- and/or ß-adrenoceptors and a downstream kinase network that phosphorylates and activates NCC, including with no lysine kinases (WNKs), STE20/SPS1-related proline-alanine-rich kinase (SPAK), and oxidative stress response 1 (OxSR1). In the present study, we used selective adrenoceptor antagonism in NE-infused male Sprague-Dawley rats to investigate the differential roles of α1- and ß-adrenoceptors in sympathetically mediated NCC regulation. NE infusion evoked salt-sensitive hypertension and prevented dietary Na+-evoked suppression of NCC mRNA, protein expression, phosphorylation, and in vivo activity. Impaired NCC suppression during high salt intake in NE- infused rats was paralleled by impaired suppression of WNK1 and OxSR1 expression and SPAK/OxSR1 phosphorylation and a failure to increase WNK4 expression. Antagonism of α adrenoceptors before high salt intake or after the establishment of salt-sensitive hypertension restored dietary Na+-evoked suppression of NCC, resulted in downregulation of WNK4, SPAK, and OxSR1, and abolished the salt-sensitive component of hypertension. In contrast, ß-adrenoceptor antagonism attenuated NE-evoked hypertension independently of dietary Na+ intake and did not restore high salt-evoked suppression of NCC. These findings suggest that a selective, reversible, a1-adenoceptor-gated WNK/SPAK/OxSR1 NE-activated signaling pathway prevents dietary Na+-evoked NCC suppression, promoting the development and maintenance of salt-sensitive hypertension. [ABSTRACT FROM AUTHOR]

Aim To evaluate the correlation between inner retinal layer thinning and the foveal microvasculature in type 2 diabetes using optical coherence tomography angiography (OCTA). Methods A cross-sectional study involved 155 diabetic eyes. All patients were divided into two groups based on diabetic retinopathy (DR) grade: no DR (NDR, n=80) and mild-to-moderate non-proliferative DR (NPDR, n=75). Foveal avascular zone (FAZ) area, FAZ circularity index, FAZ perimeter, vessel density and perfusion index of parafoveal and perifoveal area were calculated using OCTA. The thickness of the macular ganglion cell/inner plexiform layer (mGCIPL) was measured using OCT. results In both superfcial and deep retinal capillary layers (SRL and DRL), FAZ areas in the NDR (0.38 mm², 0.49 mm²) and NPDR (0.38 mm², 0.48 mm²) were greater than those in the control (0.33 mm², 0.43 mm²). The FAZ circularity index, vessel density and perfusion index in the NDR (0.63, 17.8/mm, 0.32) and NPDR (0.63, 17.5/mm, 0.32) were smaller than those in the control (0.69, 19.6/ mm, 0.39). mGCIPL thickness was signifcantly correlated with FAZ area in the SRL and DRL, as well as with FAZ circularity index, vessel density and perfusion index in the NDR and NPDR. In multivariate regression analysis, the FAZ circularity index (OR=12.2) and vessel density of the parafovea (OR=1.95) were correlated with mGCIPL thinning. Conclusion OCTA revealed that early foveal microcirculatory alterations in diabetic eyes were related to mGCIPL thickness, regardless of the presence of DR. The decrease in FAZ circularity and parafoveal vessel density were highly correlated with mGCIPL thinning. [ABSTRACT FROM AUTHOR]

The characteristics of a turbulent core-annular flow with water-lubricated high viscosity oil in a vertical pipe are investigated using direct numerical simulation, in conjunction with a level-set method to track the phase interface between oil and water. At a given mean wall friction (Reτ = uτ R/vw = 720, where uτ is the friction velocity, R is the pipe radius and vw is the kinematic viscosity of water), the total volume flow rate of a core-annular flow is similar to that of a turbulent single-phase pipe flow of water, indicating that water lubrication is an effective tool to transport high viscosity oil in a pipe. The high viscosity oil flow in the core region is almost a plug flow due to its high viscosity, and the water flow in the annular region is turbulent except for the case of large oil volume fraction (e.g. 0.91 in the present study). With decreasing oil volume fraction, the mean velocity profile in the annulus becomes more like that of turbulent pipe flow, but the streamwise evolution of vortical structures is obstructed by the phase interface wave. In a reference frame moving with the core velocity, water is observed to be trapped inside the wave valley in the annulus, and only a small amount of water runs through the wave crest. The phase interface of the core-annular flow consists of different streamwise and azimuthal wavenumber components for different oil holdups. The azimuthal wavenumber spectra of the phase interface amplitude have largest power at the smallest wavenumber whose corresponding wavelength is the pipe circumference, while the streamwise wavenumber having the largest power decreases with decreasing oil volume fraction. The overall convection velocity of the phase interface is slightly lower than the core velocity. Finally, we suggest a predictive oil holdup model by defining the displacement thickness in the annulus and considering the boundary layer characteristics of water flow. This model predicts the variation of the oil holdup with the superficial velocity ratio very well. [ABSTRACT FROM AUTHOR]

Objective To investigate the serum vitamin D level and its determinant factors in stroke patients. Methods Fifty-one stroke patients who had documented serum level of 25-hydroxyvitamin D(25(OH)D) were included. Patients were divided into subacute (n=23) and chronic groups (n=28). The mean levels of 25(OH)D of the two groups were compared. Correlations between each 25(OH)D level and post-stroke duration were also analyzed. To assess other possible influencing factors, patients were subdivided by ambulation ability and feeding methods for comparison of 25(OH)D level. Results The mean level of 25(OH)D was significantly lower in the chronic group than in the subacute group (12.3 vs. 16.3 ng/mL; p<0.05). The serum 25(OH)D level decreased according to the duration after stroke (r=- 0.52, p=0.01). Patients with a history of total parenteral nutrition had lower 25(OH)D levels than subjects who had enteral nutrition in the subacute group (7.3 vs. 18.8 ng/mL; p<0.01). However, the levels of 25(OH)D were not different between the oral feeding and tube feeding groups. Among the chronic group subjects, patients who could walk without assistance had higher 25(OH)D levels than non-ambulatory patients (ambulatory vs. nonambulatory group; 18.3 vs. 11.3 ng/mL; p<0.05). Conclusion After stroke onset, serum vitamin D level decreases with time regardless of feeding methods, and total parenteral nutrition may aggravate its deficiency. In terms of long-term care, non-ambulatory patients might be at a higher risk of vitamin D deficiency. Supplementation of vitamin D should be considered especially for stroke patients who are non-ambulatory and on total parenteral nutrition. [ABSTRACT FROM AUTHOR]

A displacement measurement system fusing a low cost real-time kinematic global positioning system (RTK-GPS) receiver and a force feedback accelerometer is proposed for infrastructure monitoring. The proposed system is composed of a sensor module, a base module and a computation module. The sensor module consists of a RTK-GPS rover and a force feedback accelerometer, and is installed on a target structure like conventional RTK-GPS sensors. The base module is placed on a rigid ground away from the target structure similar to conventional RTK-GPS bases, and transmits observation messages to the sensor module. Then, the initial acceleration, velocity and displacement responses measured by the sensor module are transmitted to the computation module located at a central monitoring facility. Finally, high precision and high sampling rate displacement, velocity, and acceleration are estimated by fusing the acceleration from the accelerometer, the velocity from the GPS rover, and the displacement from RTK-GPS. Note that the proposed displacement measurement system can measure 3-axis acceleration, velocity as well as displacement in real time. In terms of displacement, the proposed measurement system can estimate dynamic and pseudo-static displacement with a root-mean-square error of 2 mm and a sampling rate of up to 100 Hz. The performance of the proposed system is validated under sinusoidal, random and steady-state vibrations. Field tests were performed on the Yeongjong Grand Bridge and Yi Sun-sin Bridge in Korea, and the Xihoumen Bridge in China to compare the performance of the proposed system with a commercial RTK-GPS sensor and other data fusion techniques. [ABSTRACT FROM AUTHOR]

Background: This is part of a prospective study carried out as a national project to secure standardized public resources for type 2 diabetes mellitus (T2DM) patients in Korea. We compared various characteristics of long-standing T2DM patients with diabetic retinopathy (DR) and macular edema (ME). Methods: From September 2014 to July 2015, T2DM patients with disease duration of at least 15 years were recruited at a single university hospital. Clinical data and samples were collected according to the common data elements and standards of procedure developed by the Korean Diabetes Association Research Council. Each participant was assessed by ophthalmologists for DR and ME. Results: Among 220 registered patients, 183 completed the ophthalmologic assessment. DR was associated with longer disease duration (odds ratio [OR], 1.071; 95% confidence interval [Cl], 1.001 to 1.147 for non-proliferative diabetic retinopathy [NPDR]) (OR, 1.142; 95% Cl, 1.051 to 1.242 for proliferative diabetic retinopathy [PDR]) and the use of long-acting insulin (OR, 4.559; 95% Cl, 1.672 to 12.427 for NPDR) (OR, 4.783; 95% Cl, 1.581 to 14.474 for PDR), but a lower prevalence of a family history of cancer (OR, 0.310; 95% Cl, 0.119 to 0.809 for NPDR) (OR, 0.206; 95% Cl, 0.063 to 0.673 for PDR). ME was associated with higher glycosylated hemoglobin levels (OR, 1.380; 95% Cl, 1.032 to 1.845) and the use of rapid-acting insulin (OR, 5.211; 95% Cl, 1 445 to 18.794). Conclusion: Various clinical features were associated with DR and ME. Additional epidemiological and biorepository-based studies using this cohort are being conducted to deepen our understanding of diabetic complications in Korea. [ABSTRACT FROM AUTHOR]

Objective To compare gross motor function outcomes in children with moderate to severe degrees of bilateral spastic cerebral palsy (CP) who received either intensive inpatient rehabilitation or intermittent rehabilitation on an outpatient basis. Methods A non-biased retrospective chart review was done for patients diagnosed with bilateral spastic CP who received rehabilitation therapy. The intensive rehabilitation group (inpatient group) agreed to be hospitalized to receive 22 sessions of physical and occupational therapy per week for 1 month. The intermittent rehabilitation group (outpatient group) received four sessions of physical and occupational therapy per week for 3 months in an outpatient setting. Changes in the total score on the Gross Motor Function Measure (GMFM) between baseline and the follow-up period were analyzed. Results Both groups showed significant improvements in total GMFM scores at the follow-up assessment compared to that at baseline (p=0.000 for inpatient group, p=0.001 for outpatient group). The increase in mean total GMFM score after 1 month was significantly greater in the inpatient group than that in the outpatient group (p=0.020). Higher increase in GMFM score was observed in younger subjects as revealed by the negative correlation between age and the increase in GMFM score after 1 month (p=0.002, r=-0.460). Conclusion Intensive inpatient rehabilitation therapy for patients with bilateral spastic CP of moderate to severe degree was more effective for improving gross motor function than intermittent rehabilitation therapy on an outpatient basis. [ABSTRACT FROM AUTHOR]

We propose a novel 3D tracking method that supports several hundreds of pre-trained potential planar targets without losing real-time performance. This goes well beyond the state-of-the-art, and to reach this level of performances, two threads run in parallel: the foreground thread tracks feature points from frame-to-frame to ensure real-time performances, while a background thread aims at recognizing the visible targets and estimating their poses. The latter relies on a coarse-to-fine approach: assuming that one target is visible at a time, which is reasonable for digilog books applications, it first recognizes the visible target with an image retrieval algorithm, then matches feature points between the target and the input image to estimate the target pose. This background thread is more demanding than the foreground one, and is therefore several times slower. We therefore propose a simple but effective mechanism for the background thread to communicate its results to the foreground thread without lag. Our implementation runs at more than 125 frames per second, with 314 potential planar targets. Its applicability is demonstrated with an Augmented Reality book application. [ABSTRACT FROM AUTHOR]

In this paper, we introduce very thin Indium tin oxide (ITO) layers (5, 10, and 15 nm) hybridized with a metal mesh to produce high-performance transparent conductive layers (TCLs) in near-ultraviolet light-emitting diodes (NUV LEDs). Using UV–vis–IR spectrometry, Hall measurement, and atomic force microscopy, we found that 10 nm was the optimal thickness for the very thin ITO layers in terms of outstanding transmittance and sheet resistance values as well as stable contact properties when hybridized with the metal mesh. The proposed layers showed a value of 4.56 Ω/□ for sheet resistance and a value of 89.1% for transmittance. Moreover, the NUV LEDs fabricated with the hybrid TCLs achieved ∼140% enhanced light output power compared to that of 150 nm thick ITO layers. Finally, to verify the practical usage of the TCLs for industrial applications, we packaged the NUV LED chips and obtained improved turn-on voltage (3.48 V) and light output power (∼116%) performance. [ABSTRACT FROM AUTHOR]

The displacement responses of civil structures reveal the overall state of the structures and consist of two distinctive dynamic behaviors: pseudo-static deflection and structural vibration. In this study, a dynamic displacement estimation system is developed by integrating a laser Doppler vibrometer (LDV) and terrestrial laser scanner (TLS). The TLS displacement data contaminated with high noise and measured with a low sampling rate is converted to high sampling rate dynamic displacements including the pseudo-static motion by fusing with the velocity data measured by the LDV which are at a high sampling rate but miss the pseudo-static components. [ABSTRACT FROM AUTHOR]

Dynamic displacement measurement is often preferred over conventional acceleration measurement in the field of structural engineering. In this paper, a new methodology for dynamic displacement measurement using a terrestrial laser scanner (TLS) is presented. The methodology operates the TLS so as to measure multiple target points in a scan and to determine dynamic displacement from the distance data of the points. To lessen the TLS’s inherent high noise contamination, optimal weighted averaging, i.e. the kriging method, is adopted, utilizing multiple neighbor points provided by TLS’s spatial-temporal measurement. After conducting two experiments of vibration testing, it has been verified that the noise reduction efficiency of the proposed methodology does not change significantly with respect to the vibration characteristic of structures. [ABSTRACT FROM AUTHOR]