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In this work, direct numerical simulation (DNS) is used to investigate how airfoil shape affects wake structure and performance during a pitching-heaving motion. First, a class-shape transformation (CST) method is used to generate airfoil shapes. CST coefficients are then varied in a parametric study to create geometries that are simulated in a pitching and heaving motion via an immersed boundary method-based numerical solver. The results show that most coefficients have little effect on the propulsive efficiency, but the second coefficient does have a very large effect. Looking at the CST basis functions shows that the effect of this coefficient is concentrated near the 25% mark of the foils chord length. By observing the thrust force and hydrodynamic power through a period of motion it is shown that the effect of the foil shape change is realized near the middle of each flapping motion. Through further inspection of the wake structures, we conclude that this is due to the leading-edge vortex attaching better to the foil shapes with a larger thickness around 25% of the chord length. This is verified by the pressure contours, which show a lower pressure along the leading edge of the better performing foils. The more favorable pressure gradient generated allows for higher efficiency motion.

Background: Total percutaneous closure of a femoral artery access site using Perclose ProGlide has become prevalent after percutaneous endovascular aortic repair and veno-arterial extracorporeal membrane oxygenation. Objective: To evaluate the safety and efficacy of total percutaneous closure of the femoral artery access site after veno-arterial extracorporeal membrane oxygenation compared with that after endovascular aortic repair. Methods: This was a retrospective observational study conducted over an almost 4-year period and included 88patients who underwent endovascular aortic repair (64 patients) and veno-arterial extracorporeal membrane oxygenation (24 patients). The femoral artery puncture sites of the patients were closed percutaneously using Perclose ProGlide devices. Technical success was defined as successful arterial closure of the common femoral artery, without additional surgical or endovascular procedures. Access site complications, such as major bleeding requiring transfusion or surgical intervention, minor bleeding, groin infection, pseudoaneurysm, and lymphocele, were recorded 24 h and 30 days after arterial closure. Results: Each group's technical success rates were 95.8% (veno-arterial extracorporeal membrane oxygenation) and 92.2% endovascular aortic repair, respectively. There were no differences in the periprocedural complications of major bleeding, pseudoaneurysm, minor bleeding, acute limb ischemia, and groin infection. Furthermore, no arterial thrombosis, dissection, stenosis, arteriovenous fistula, hematoma, groin infection, or lymphocele was observed at the patients' access site who underwent follow-up ultrasound examination. There was no significant difference in the technical success rate of percutaneous closure by the Perclose ProGlide device in the endovascular aortic repair and veno-arterial extracorporeal membrane oxygenation groups. Also, no periprocedural or 30-day complications were observed at the access site of the endovascular aortic repair and veno-arterial extracorporeal membrane oxygenation patients.

Snoring is a common breathing disorder during sleep. It is hypothesized that head posture during sleep could change the bending angle and the cross-sectional area of the airway, which could cause changes in airflow and aerodynamic pressure during sleep. In this work, an experiment-driven computational study was conducted to examine the aerodynamics and pressure behavior in human upper airway during snoring. An anatomically accurate human upper airway model associated with a dynamic uvula was reconstructed from human magnetic resonance image (MRI) and high-speed photography. The airway bending at different head posture and the corresponding change in airway cross-sectional area are modeled based on measurements from literature. An immersed-boundary-method (IBM)-based direct numerical simulation (DNS) flow solver was adopted to simulate the corresponding unsteady flows of the bent airway model in all their complexity. Analyses were performed on vortex dynamics and pressure fluctuations in the pharyngeal airway. It was found that the vortex formation and aerodynamic pressure were significantly affected by the airway bending. A head-neck junction extension posture tends to facilitate the airflow through the upper human airway. Fast Fourier transformation (FFT) analysis of the pressure time history revealed the existence of higher order harmonics of base frequency with significant pressure amplitudes and energy intensities. The results of this study help better understand the pathology of snoring under the influence of head posture from an aerodynamic perspective.

To evaluate the safety and efficacy of total percutaneous closure of the femoral artery access site after veno-arterial extracorporeal membrane oxygenation (VA-ECMO) with the Perclose ProGlide device. This retrospective observational study during an almost 2-year period included 21 patients who underwent VA-ECMO in whom the femoral artery puncture site was closed percutaneously with Perclose ProGlide devices. Technical success was defined as successful arterial closure of the common femoral artery, without the need for additional surgical or endovascular procedures. Access site complications were recorded at 24 hours and 30 days after arterial closure, such as major bleeding requiring transfusion or surgical intervention, minor bleeding, groin infection, pseudoaneurysm, and lymphocele. Technical success was achieved in 20 patients (95.2%). One patient required surgical repair for an access site pseudoaneurysm. Eighteen femoral arteries were closed with 2 devices each, while 3 patients required the use of a third device for femoral artery access site closure to achieve adequate hemostasis. No arterial thrombosis, arterial dissection, arterial stenosis, groin infection, or arteriovenous fistula occurred during the periprocedural period (within 24 hours of arterial closure) or during 30-day follow-up. Percutaneous closure with the Perclose ProGlide device is a feasible procedure for closing femoral arterial access sites after VA-ECMO, with a low incidence of access site complications.

We report the first case of pulmonary scedosporiosis detected by next-generation sequencing (NGS) from bronchoalveolar lavage fluid (BALF) in a 67-year-old male with bronchiectasis and hematopoietic failure. Scedosporium apiospermum is a ubiquitous organism present in the environment with intrinsic resistance to many antifungal agents. The patient developed respiratory failure, pulmonary consolidation, and septic shock shortly thereafter, and responded poorly to antifungal therapy. This case highlights the combined application of NGS and traditional fungal culture in the clinical diagnosis of pulmonary invasive fungal disease. NGS is proposed as an important adjunctive diagnostic approach for uncommon pathogens. Keywords: Scedosporium apiospermum, Pulmonary scedosporiosis, Next-generation sequencing

Autism spectrum disorders (ASD) may result from a combination of genetic and environmental factors, and impact neurological functions and behaviors. Sialic acid (SA) is an indispensable nutrient for early brain development, and its polymer polySia (PSA) can modify neural cell adhesion molecules (NCAM), thereby indirectly mediating neuronal outgrowth, synaptic connectivity and memory formation. To investigate the association between SA and ASD, we conducted a case-control study.The study sample included 82 autistic children and 60 healthy children. We measured the levels of plasma SA and serum anti-gangliosides M1 antibodies (anti-GM1 antibodies) in the ASD and control groups. We also examined the severity of autistic children.The level of plasma SA in the control group was significantly higher than that in the ASD group (p .01). Autistic children had higher positive rates of anti-GM1 antibodies (37.8%) than controls (21.67%, P = .04). However, there was no correlation between autistic severity and the levels of SA. SA may be as a biomarker for diagnosis of ASD with a positive predictive value of 84.42%, a negative predictive value of 73.85% and an area under the ROC curve value of 0.858.These results indicate that SA and anti-GM1 antibodies are associated with ASD. Our data suggested that future studies to explore the function of SA in the etiology of ASD may be needed.

Wheel force transducer (WFT) plays a key role in automobile detection technology, and they can measure the force and torque applied in the wheel. However, the most current generation of WFT are commercial products which are expensive and their technical information is not public. Accordingly, a three-dimensional wheel force sensor based on spoke structure with eight elastic beams is presented in this paper. Firstly, the overall structure of the proposed WFT is described, and then the design of the elastic body is introduced briefly. Afterwards, the strain gauge arrangement, the principle of strain measurement and the connection mode of bridge circuit are analyzed in detail. Finally, static calibration and dynamic tests is performed. Experiment results demonstrate the proposed WFT has the characteristic of large scale, good linearity, low hysteresis, high repeatability and weak interdimensional couplings. The maximum nonlinearity error, the maximum hysteresis error and the maximum repeatability error of the proposed WFT is 0.6% F.S, 0.7% F.S and 0.4% F.S separately.

Influence of the human body on a 5.8GHz wideband antenna is reported in this paper. Limited to 30×30 mm2 area on a PCBoard with er = 4.4, proposed antenna has two U-shaped, two F-shaped and two L-shaped slots as additional resonators to achieve wide-band operation. Measured-10 dB bandwidth is 2.68GHz (5.63 GHz~8.31 GHz). When the antenna applied to wireless body area network (WBAN) application, the characteristic of proposed antenna had been degraded to near to the-10 dB return loss. The performance of the designed antenna on body was characterized through simulations using the Finite Element Method and Method of Moment.

The present study was conducted to evaluate the effect of a fraction of macroporous resin (FMR), a bioactive component of Smilax china L., on benign prostatic hyperplasia (BPH) in castrated rats induced by testosterone propionate. Rats were randomly divided into five groups: the negative control group (sham-operated), the model group, two FMR-treated groups (at doses of 300 mg/kg and 600 mg/kg of body weight), and the positive control group (treated with finasteride at the dose of 3 mg/kg). Drugs were administered once a day for three consecutive weeks by gastric gavage. Prostates were weighed, testosterone and dihydrotestosterone (DHT) levels in serum were determined, and histopathological examinations were carried out. FMR treatment inhibited prostatic hyperplasia, reducing the DHT level in serum and improving the prostate gland morphology compared with the model group. The overall results of this study suggest that FMR is effective at inhibiting experimentally induced prostate enlargement, and it presents a valuable resource for the treatment of human BPH.

Shipborne balanced serial communication interface adopts balanced driving and differential receiving circuit, so its anti-interference ability strengthens. However, ground signal connecting is ignored when forming a balanced serial communication link. This paper analyzes its potential risk of common mode voltage interference and radiation EMI. Furthermore, when reasoning grounding of balanced serial communication interface, we give several measures, such as floating ground and isolated interface, to enhance properties of grounding system for shipborne balanced serial communication interface according to engineering experience.

Rechargeable batteries have attracted increasing attention as power technologies for emerging electric vehicles and grid energy storage, which are expected to mitigate the environmental pollution caused by the use of fossil fuels. Although graphite/lithium transition-metal-oxides (LiCoO 2 , LiNiO 2 , and LiMn 2 O 4 , etc.) and lithium-ion batteries have been the dominant power sources for portable electronics and are used in hybrid electric vehicles, the limited ore resources of these materials make durative rising price. Most crucially, the limitations of potential energy density of these metal-oxide cathode materials are a main restriction in terms of large-scale applications of batteries, particularly in electric vehicles and hybrid electric vehicles. [ 1,2 ] Therefore, it has become urgent to search for alternative energy-storage systems that could complement the existing lithium-ion batteries and that simultaneously have high energy density and long cycle life, in addition to safety and low cost. Alternatively, sodium-sulfur (Na-S) batteries offer low cost, high capacity and high safety, showing great promissing for grid-scale applications. [ 2 ] Both Na and S are abundant and nontoxic elementals on the earth, providing larger availability and lower material cost over the conventional lithium-ion batteries.

Background Ultrasonography is a convenient technique to investigate muscle properties and has been widely used to look into muscle functions since it is non-invasive and real-time. Muscle thickness, a quantification which can effectively reflect the muscle activities during muscle contraction, is an important measure for musculoskeletal studies using ultrasonography. The traditional manual operation to read muscle thickness is subjective and time-consuming, therefore a number of studies have focused on the automatic estimation of muscle fascicle orientation and muscle thickness, to which the speckle noises in ultrasound images could be the major obstacle. There have been two popular methods proposed to enhance the hyperechoic regions over the speckles in ultrasonography, namely Gabor Filtering and Multiscale Vessel Enhancement Filtering (MVEF). Methods A study on gastrocnemius muscle is conducted to quantitatively evaluate whether and how these two methods could help the automatic estimation of the muscle thickness based on Revoting Hough Transform (RVHT). The muscle thickness results obtained from each of the two methods are compared with the results from manual measurement, respectively. Data from an aged subject with cerebral infarction is also studied. Results It’s shown in the experiments that, Gabor Filtering and MVEF can both enable RVHT to generate comparable results of muscle thickness to those by manual drawing (mean ± SD, 1.45 ± 0.48 and 1.38 ± 0.56 mm respectively). However, the MVEF method requires much less computation than Gabor Filtering. Conclusions Both methods, as preprocessing procedure can enable RVHT the automatic estimation of muscle thickness and MVEF is believed to be a better choice for real-time applications.