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The present study investigates impact of nanodroplets on liquid films with varied film thicknesses over hydrophilic to hydrophobic surfaces via molecular dynamics simulations. A new crown pattern, hollow crown, is observed on medium liquid films for nanodroplets, whereas it is not reported for millimeter-sized droplets. Holes (or hollows) are attributed to capillary vibration of a nanometer-thick liquid film. The occurrence of holes is inhibited effectively for deep liquid films because the cavity thickness is much larger than the amplitude of capillary vibration. Surface wettability has a significant influence on thin and medium liquid films for nanodroplets, whereas it only affects thin liquid films for macrodroplets because the range of solid–liquid intermolecular forces is comparable to the size of droplets when the size of droplets reduces to the nanoscale. Subsequently, the accuracies of the existing macroscale models for predicting the time-dependent crown radius of nanodroplets are tested by simulated results. The results show that the macroscale models cannot capture the time-dependent crown radius of nanodroplets. On the basis of energetics analysis, we prove that the failure of macroscale models is attributed to the distinct difference in viscous dissipation mechanisms between macroscale and nanoscale droplets. [ABSTRACT FROM AUTHOR]

Simple Summary: This study proposed the "Residual-Dense-Attention" (RDA) U-Net model architecture to automatically segment organs and lesions in computed tomography (CT) images. The RDA U-Net used ResBlock and DenseBlock at the encoder. Attention gates were used at the decoder position to help the model suppress irrelevant areas of the CT image. Forty-one patients' bladder images were provided for training. The RDA U-Net provided faster but satisfactory segmentation results for bladder cancers and lesions. In today's high-order health examination, imaging examination accounts for a large proportion. Computed tomography (CT), which can detect the whole body, uses X-rays to penetrate the human body to obtain images. Its presentation is a high-resolution black-and-white image composed of gray scales. It is expected to assist doctors in making judgments through deep learning based on the image recognition technology of artificial intelligence. It used CT images to identify the bladder and lesions and then segmented them in the images. The images can achieve high accuracy without using a developer. In this study, the U-Net neural network, commonly used in the medical field, was used to extend the encoder position in combination with the ResBlock in ResNet and the Dense Block in DenseNet, so that the training could maintain the training parameters while reducing the overall identification operation time. The decoder could be used in combination with Attention Gates to suppress the irrelevant areas of the image while paying attention to significant features. Combined with the above algorithm, we proposed a Residual-Dense Attention (RDA) U-Net model, which was used to identify organs and lesions from CT images of abdominal scans. The accuracy (ACC) of using this model for the bladder and its lesions was 96% and 93%, respectively. The values of Intersection over Union (IoU) were 0.9505 and 0.8024, respectively. Average Hausdorff distance (AVGDIST) was as low as 0.02 and 0.12, respectively, and the overall training time was reduced by up to 44% compared with other convolution neural networks. [ABSTRACT FROM AUTHOR]

This work presents a novel integrated device that combines a hybrid stepping motor (HSM) and a planetary gear train (PGT) reducer as a compact structural assembly. In this study, a systematic design process was developed to efficiently implement the integrated device. By applying the gear profile on the rotor and the stator, a 9:1 two stages PGT reducer is integrated with a standard 42 type 2-pole stepping motor. The quadratic interpolation method was applied to derive the optimal design of the geometric configurations of the HSM. The electromagnetic characteristics and output performance of the integrated device, including flux linkage, back-emf constant, holding torque, and output torque, were analysed. Finally, the output performance between an existing design and the novel integrated design were compared. The two designs had similar output and holding torque, but the torque ripple was approximately 44.7% lower in the integrated device from 30% to 16.6%. In addition, the axial space arrangement was reduced by 5.2% from 67.7mm to 64.1 5mm, and the torque density was improved by 4.4%. [ABSTRACT FROM AUTHOR]

In this study, the concrete is mixed with glass fibers which are 0.5%, 1.0% and 1.5% of cement weight and 0.6 cm long. The effect of fiber addition level on the compressive strength, bending strength and residual compressive strength and thermal conductivity after heating of concrete is discussed. The test results show that an appropriate addition of glass fiber to the concrete at room temperature is favorable for the compressive strength. A low addition of relatively short glass fiber has insignificant effect on the bending strength. However, the adverse effect on the bending strength will increase if the addition level is too high. The addition of glass fiber can improve the loss of concrete strength under the effect of high temperature not exceeding 500°C, and a relatively high compressive strength remains under the effect of high temperature not exceeding 800°C. The high temperature can reduce the thermal conductivity of glass concrete, and the higher the addition level of glass fiber is, the lower is the thermal conductivity. Keywords: Glass fiber, concrete, heating, thermal conductivity

Background: The fetal brain developmental changes of water diffusivity and perfusion has not been extensively explored.Purpose/hypothesis: To evaluate the fetal brain developmental changes of water diffusivity and perfusion using intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI).Study Type: Prospective.Population: Seventy-nine normal singleton fetuses were scanned without sedation of healthy pregnant women.Field Strength/sequence: 5 T MRI/T1 /2 -weighted image and IVIM-DWI.Assessment: Pure diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) values were calculated in the frontal (FWM), temporal (TWM), parietal (PWM), and occipital white matter (OWM) as well as cerebellar hemisphere (CH), basal ganglia region (BGR), thalamus (TH), and pons using an IVIM model.Statistical Tests: One-way analysis of variable (ANOVA) followed by Bonferroni post-hoc multiple comparison was employed to reveal the difference of IVIM parameters among the investigated brain regions. The linear and the nonlinear polynomial regression analyses were utilized to reveal the correlation between gestational age (GA) and IVIM parameters.Results: There were significant differences in both D (F(7,623) = 96.64, P = 0.000) and f values (F(7,623) = 2.361, P = 0.0219), but not D* values among the varied brain regions. D values from TWM (r2  = 0.1402, P = 0.0002), PWM (r2  = 0.2245, P = 0.0002), OWM (r2  = 0.2519, P = 0.0002), CH (r2  = 0.2245, P = 0.0002), BGR (r2  = 0.3393, P = 0.0001), TH (r2  = 0.1259, P = 0.0001), and D* value from pons (r2  = 0.2206, P = 0.0002) were significantly correlated with GA using linear regression analysis. Quadratic regression analysis led to results similar to those using the linear regression model.Data Conclusion: IVIM-DWI parameters may indicate fetal brain developmental alterations but the conclusion is far from reached due to the not as high-powered correlation between IVIM parameters and GA.Level Of Evidence: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;50:899-909. [ABSTRACT FROM AUTHOR]

Nanotechnology utilizes engineered materials and devices which function with biological systems at the molecular level and could transform the management of neurodegenerative diseases (NDs) by provoking, reacting to, and intermingling with target sites to stimulate physiological responses while minimizing side effects. Blood–brain barrier (BBB) protects the brain from harmful agents, and transporting drugs across the BBB is a major challenge for diagnosis, targeting, and treatment of NDs. The BBB provides severe limitations for diagnosis and treatment of Alzheimer's disease (AD), Parkinson's disease (PD), and various other neurological diseases. Conventional drug delivery systems generally fail to cross the BBB, thus are inefficient in treatment. Although gradual development through research is ensuring the progress of nanotheranostic approaches from animal to human modeling, aspects of translational applicability and safety are a key concern. This demands a deep understanding of the interaction of body systems with nanomaterials. There are various plant-based nanobioactive compounds which are reported to have applicability in the diagnosis and treatment of these NDs. This review article provides an overview of applications of nanotheranostics in AD and PD. The review also discusses nano-enabled drug delivery systems and their current and potential applications for the treatment of various NDs. [ABSTRACT FROM AUTHOR]

A very-low-profile grounded coplanar waveguide (GCPW)-fed slot antenna with an antenna thickness of 0.8 mm (about 0.0064λ at 2.4 GHz) and a compact size of 15 mm × 40 mm (about 0.12λ × 0.32λ at 2400 MHz) for 2.4/5.8 GHz dual-band wireless local area network on-body antenna application is presented. The GCPW slot antenna consists of a top ground with the GCPW feedline and radiating slot embedded thereon and a bottom ground spaced 0.8 mm to the top ground. The radiating slot is an asymmetric T-shaped slot having a longer slot path for 2400∼2500 MHz band and a shorter slot path for 5725∼5875 MHz band. It is convenient to tune the dual-band operation by adjusting the lengths of the longer and shorter slot paths, respectively. Additionally, owing to the presence of the bottom ground, the GCPW slot antenna has decreased backward radiation. This causes the antenna's impedance matching to be very slightly varied when it is in the proximity of a human body. [ABSTRACT FROM AUTHOR]

• Wettability of the binary mixed substrate is studied. • A surface potential energy analysis method is used to verify nucleation sites. • The binary mixed substrate can effectively enhance the nucleation process. • No sacrifice on the departure performance of the binary mixed substrate. • A moderated hydrophilic ratio is needed to enhance condensation performance. Sophisticated and expensive surface texture design and manufacturing are commonly needed to achieve efficient surfaces with enhanced condensation performances. The high nucleation rate and high droplet removal capacity of a substrate surface acquire trade-off, whose mechanisms have not explicitly been comprehended. Based on the assumption that hydrophilic spots would improve nucleation while a hydrophobic surface can facilitate droplet removal rate, this work studied the nucleation and departure processes on a binary mixed substrate with randomly distributed hydrophilic atoms, with homogeneous substrates being as comparison references. The molecular dynamics simulation results showed that the wettability of the binary mixed substrate could be estimated by the form of the Cassie equation. Unlike the randomly nucleated clusters on a homogeneous substrate, the surface energy analysis verifies that the clusters tend to form on the areas with enriched hydrophilic atoms on a binary mixed substrate. Conversely, the droplets also tend to stick on the hydrophilic areas to deteriorate droplet removal efficiency. Combined with a probability analysis by the Monte Carlo method and MD simulation, a moderated ratio(r m = 25% in this work) was shown to furnish better nucleation properties with minimal deterioration in departure properties than the mono-wettability substrate with the same contact angle. [ABSTRACT FROM AUTHOR]

This paper presents a new actuation mechanism to drive comb-drive actuators. An asymmetric configuration of the finger overlap was used to generate capacitive coupling for the actuation mechanism. When the driving voltages were applied on the stators, a voltage would be induced at the rotor due to the capacitive coupling. Then, an electrostatic force would be exerted onto the rotor due to the voltage differences between the stators and the rotor. The actuator’s static displacement and resonant frequency were theoretically analyzed. To verify the design, a comb-drive actuator with different initial finger overlaps, i.e., 159.3 μm and 48.9 μm on each side, was fabricated and tested. The results show that the actuator worked well using the proposed actuation mechanism. A static displacement of 41.7 μm and a resonant frequency of 577 Hz were achieved. Using the actuation mechanism, no electrical connection is required between the rotor and the outside power supply. This makes some comb-drive actuators containing heterogeneous structures easy to design and actuate. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the synthesis of three cinchona alkaloid copolymers through copolymerization. It notes that asymmetric dihydroxylation (AD) of olefins was performed to examine the catalytic activity of these copolymers. Results of the study showed that the nature of olefins influenced the catalytic efficiency of the copolymers. It also found that centrifugation can be used to recover the polymeric cinchona alkaloid at the end of the reaction.

Biophysical stimulation alters bone-forming cell activity, bone formation and remodeling. The effect of piezoelectric microvibration stimulation (PMVS) intervention on osteoporosis development remains uncertain. We investigated whether 60 Hz, 120 Hz, and 180 Hz PMVS (0.05 g, 20 min/stimulation, 3 stimulations/week for 4 consecutive weeks) intervention affected bone integrity in ovariectomized (OVX) mice or osteoblastic activity. PMVS (120 Hz)-treated OVX mice developed fewer osteoporosis conditions, including bone mineral density loss and trabecular microstructure deterioration together with decreased serum resorption marker CTX-1 levels, as compared to control OVX animals. The biomechanical strength of skeletal tissue was improved upon 120 Hz PMVS intervention. This intervention compromised OVX-induced sparse trabecular bone morphology, osteoblast loss, osteoclast overburden, and osteoclast-promoting cytokine RANKL immunostaining and reversed osteoclast inhibitor OPG immunoreactivity. Osteoblasts in OVX mice upon PMVS intervention showed strong Wnt3a immunoreaction and weak Wnt inhibitor Dkk1 immunostaining. In vitro, PMVS reversed OVX-induced loss in von Kossa-stained mineralized nodule formation, Runx2, and osteocalcin expression in primary bone-marrow stromal cells. PMVS also promoted mechanoreceptor Piezo1 expression together with increased microRNA-29a and Wnt3a expression, whereas Dkk1 rather than SOST expression was repressed in MC3T3-E1 osteoblasts. Taken together, PMVS intervention promoted Piezo1, miR-29a, and Wnt signaling to upregulate osteogenic activity and repressed osteoclastic bone resorption, delaying estrogen deficiency-induced loss in bone mass and microstructure. This study highlights a new biophysical remedy for osteoporosis. [ABSTRACT FROM AUTHOR]

Skeletal tissue involves systemic adipose tissue metabolism and energy expenditure. MicroRNA signaling controls high-fat diet (HFD)-induced bone and fat homeostasis dysregulation remains uncertain. This study revealed that transgenic overexpression of miR-29a under control of osteocalcin promoter in osteoblasts (miR-29aTg) attenuated HFD-mediated body overweight, hyperglycemia, and hypercholesterolemia. HFD-fed miR-29aTg mice showed less bone mass loss, fatty marrow, and visceral fat mass together with increased subscapular brown fat mass than HFD-fed wild-type mice. HFD-induced O2 underconsumption, respiratory quotient repression, and heat underproduction were attenuated in miR-29aTg mice. In vitro, miR-29a overexpression repressed transcriptomic landscapes of the adipocytokine signaling pathway, fatty acid metabolism, and lipid transport, etc., of bone marrow mesenchymal progenitor cells. Forced miR-29a expression promoted osteogenic differentiation but inhibited adipocyte formation. miR-29a signaling promoted brown/beige adipocyte markers Ucp-1, Pgc-1α, P2rx5, and Pat2 expression and inhibited white adipocyte markers Tcf21 and Hoxc9 expression. The microRNA also reduced peroxisome formation and leptin expression during adipocyte formation and downregulated HFD-induced leptin expression in bone tissue. Taken together, miR-29a controlled leptin signaling and brown/beige adipocyte formation of osteogenic progenitor cells to preserve bone anabolism, which reversed HFD-induced energy underutilization and visceral fat overproduction. This study sheds light on a new molecular mechanism by which bone integrity counteracts HFD-induced whole-body fat overproduction. [ABSTRACT FROM AUTHOR]