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The difficulty in determining which structures are crucial to ensure a natural-looking ear has been plaguing surgeons for many years. This preliminary study explores the feasibility of training convolutional neural network (CNN) models to evaluate a reconstructed auricle as accurate as a human would. By visualizing the attention of trained models, the criteria for the design of a natural-looking auricle can be established. A total of 400 pictures were evaluated by 20 volunteers, and 20 labeled datasets were generated, which were then used to train ResNet models that had been pre-trained on ImageNet. The saliency maps and occlusion maps of each trained model were calculated to capture the attention of models. The average accuracy of the 20 models was 0.8245 ± 0.0356 (>0.80), and the evaluation results of the trained model and the medical student showed a significant correlation (P < 0.05). For the attention visualization of auricles labeled as normal, distribution of the highlighted portions corresponded to a linear contour of the helix, the inferior crura of the antihelix, and the contour of the concha. A CNN can provide an evaluation of a reconstructed auricle in a manner similar to that of a medical student. Saliency maps generated by the CNN demonstrate the subjective view, which was consistent with professional opinion. [ABSTRACT FROM AUTHOR]

The construction of large-scale photovoltaic plants will inevitably change the local environment. We consider that the influences of such increasing large-scale photovoltaic installations on radiation, temperature, wind profile and other factors within the region can be described in a layer of photovoltaic canopy. This paper improves the UCRC-Solar model for photovoltaic plants, with reference to the calculation of sensible heat flux of the underlying forest surface. Model verification was done with measured data from the Red Rock photovoltaic plant, Arizona, USA. In this study, it indicates that photovoltaic plant has locally generated heat island effects in daytime. The calculation of local microclimate changes before and after the construction of the photovoltaic plants and, the impact of photovoltaic coverage finds an increase in the temperature daily range and a reduction in the ground temperature by about 5 °C. Furthermore, a 15 % increase in photovoltaic coverage increased the daily 3 m air temperature difference by 0.55 °C and reduced the ground temperature by 3.6 °C in the day and 1.1 °C at night, respectively. In the future, rain and snow processes would be considered to further explore the microclimate impact of photovoltaic plants. • Improved energy balance model under the definition of photovoltaic canopy. • Quantitatively studied influences of photovoltaic plants on local microclimate. • Photovoltaic power plant has locally generated heat island effects in daytime. [ABSTRACT FROM AUTHOR]

Heat-modified citrus pectin, a water-soluble indigestible polysaccharide fiber derived from citrus fruits and modified by temperature treatment, has been reported to exhibit anticancer effects. However, the bioactive fractions and their mechanisms remain unclear. In this current study, we isolated an active compound, trans-4,5-dihydroxy-2-cyclopentene-l-one (DHCP), from heat-treated citrus pectin, and found that is induces cell death in colon cancer cells via induction of mitochondrial ROS. On the molecular level, DHCP triggers ROS production by inhibiting the activity of succinate ubiquinone reductase (SQR) in mitochondrial complex II. Furthermore, cytotoxicity, apoptotic activity, and activation of caspase cascades were determined in HCT116 and HT-29 cell-based systems, the results indicated that DHCP enhances the sensitivity of cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), with DHCP-induced ROS accounting for the synergistic effect between DHCP and TRAIL. Furthermore, the combination of DHCP and TRAIL inhibits the growth of HCT116 and HT-29 xenografts synergistically. ROS significantly increases the expression of TRAIL death receptor 5 (DR5) via the p53 and C/EBP homologous protein pathways. Collectively, our findings indicate that DHCP has a favorable toxicity profile and is a new TRAIL sensitizer that shows promise in the development of pectin-based pharmaceuticals, nutraceuticals, and dietary agents aimed at combating human colon cancer. [ABSTRACT FROM AUTHOR]

Sirt6 is an NADH (NAD+)-dependent deacetylase with a critical role in hepatic lipid metabolism. Ketogenesis is controlled by a signaling network of hepatic lipid metabolism. However, how Sirt6 functions in ketogenesis remains unclear. Here, we demonstrated that Sirt6 functions as a mediator of ketogenesis in response to a fasting and ketogenic diet (KD). The KD-fed hepatocyte-specific Sirt6 deficiency (HKO) mice exhibited impaired ketogenesis, which was due to enhanced Fsp27 (fatspecific induction of protein 27), a protein known to regulate lipid metabolism. In contrast, overexpression of Sirt6 in mouse primary hepatocytes promoted ketogenesis. Mechanistically, Sirt6 repressed Fsp27β expression by interacting with Crebh (cAMP response element--binding protein H) and preventing its recruitment to the Fsp27βgene promoter. The KD-fed HKO mice also showed exacerbated hepatic steatosis and inflammation. Finally, Fsp27 silencing rescued hypoketonemia and other metabolic phenotypes in KD-fed HKO mice. Our data suggest that the Sirt6--Crebh--Fsp27 axis is pivotal for hepatic lipid metabolism and inflammation. Sirt6 may be a pharmacological target to remedy metabolic diseases. [ABSTRACT FROM AUTHOR]

Abstract Density function theory (DFT) can be used to investigate the mechanisms of complex catalysis and adsorption reactions. On this basis, the application of DFT in catalysis/adsorption reaction system is summarized in this paper. Then it puts forward ideas for research, explores the DFT simulation of CO 2 adsorption and tar removal in biomass thermal conversion and eventually lays a foundation for experimental and theoretical exploration. [ABSTRACT FROM AUTHOR]

The processing of an ultra-short pulse laser is widely discussed and used in the field of micro machining, especially for precision processing of the hard and brittle materials. Firstly, the ablation ability would reduce with the defocusing distance increase in theory. However, it was found that the microchannel ablation depth is not sensitive to the defocusing distance in the experiments. The theoretical analysis and simulation calculation were carried out in this paper in order to explain the reason for the relationship between them. Secondly, the size of microchannel structure of the silicon wafer and quartz glass in our experiments were determined obviously by the main processing parameters of femtosecond laser. Furthermore, the influence of laser parameters on the structure size was studied. It was proven that the high quality processed of microchannel depend on the reasonable selection and combination of the parameters by femtosecond laser, which provided an important suggestion to process microchannel precisely. [ABSTRACT FROM AUTHOR]

The plasma brightness cannot be used as a direct indicator of ablation depth detection by femtosecond laser was experimentally demonstrated, which led to the difficulty of depth measurement in the maching process. The tests of microchannel milling on the silicon wafer were carried out in the micromachining center in order to obtain the influences of parameters on the ablation depth. The test results showed that the defocusing distance had no significant impact on ablation depth in LAV effective range. Meanwhile, the reason of this was explained in this paper based on the theoretical analysis and simulation calculation. Then it was proven that the ablation depth mainly depends on laser fluence, step distance and scanning velocity. Finally, a research was further carried out to study the laser parameters which relate with the microchannel ablation depth inside the quartz glass for more efficiency and less cost in processing by femtosecond laser. [ABSTRACT FROM AUTHOR]

Osteoporosis is caused by the disruption in homeostasis between bone formation and bone resorption. Conventional management of osteoporosis involves systematic drug administration and hormonal therapy. These treatment strategies have limited curative efficacy and multiple adverse effects. Biomaterials-based therapeutic strategies have recently emerged as promising alternatives for the treatment of osteoporosis. The present review summarizes the current status of biomaterials designed for managing osteoporosis. The advantages of biomaterials-based strategies over conventional systematic drug treatment are presented. Different anti-osteoporotic delivery systems are concisely addressed. These materials include injectable hydrogels and nanoparticles, as well as anti-osteoporotic bone tissue engineering materials. Fabrication techniques such as 3D printing, electrostatic spinning and artificial intelligence are appraised in the context of how the use of these adjunctive techniques may improve treatment efficacy. The limitations of existing biomaterials are critically analyzed, together with deliberation of the future directions in biomaterials-based therapies. The latter include discussion on the use of combination strategies to enhance therapeutic efficacy in the osteoporosis niche. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: Our objective was to examine the association between adherence to tyrosine kinase inhibitors (TKIs) and molecular monitoring and the risk of disease progression or mortality among patients with chronic phase chronic myeloid leukemia (CML).Design: We assembled a retrospective cohort of patients with CML (chronic phase, no prior cancer history, and confirmed to be Philadelphia chromosome positive) using data from electronic health records and chart reviews. Medication possession ratio (MPR) was used to measure drug adherence.Setting: A large, community-based, integrated health plan in Southern California.Participants: The cohort consisted of 245 adult patients (≥18 years old) with Philadelphia positive chronic phase CML diagnosed from 2001 to 2012 and followed through 2013.Main Outcome Measures: In survival analyses, we examined the association of TKI adherence (MPR) and polymerase chain reaction (PCR) monitoring test frequency with the composite clinical outcome, progression to accelerated phase disease-blast crisis or mortality (progression-free survival). The cohort was followed for a maximum of 13 years (median 4.6 years).Results: Over 90% of the cohort initiated TKI therapy within 3 months of diagnosis, and the mean MPR was 88% (SD 18%). Virtually all patients (96%) started on imatinib. The rates of progression to accelerated phase-blast crisis and mortality were lower in patients with greater TKI adherence (20.4/1000 person-years) versus lower adherence (27.0/1000 person-years). Patients who underwent PCR monitoring had a significantly reduced risk of progression or mortality, which was seen in patients with high and low TKI adherence status from both the groups (hazard ratio [HR] 0.07 [95% CI 0.03-0.19 if MPR >90%] and HR 0.70 [95% CI 0.02-0.21 if MPR<90%]).Conclusion: Our results suggest that close clinical monitoring, which includes PCR monitoring in patients with high and low TKI drug adherence, is associated with a lower risk of progression or mortality. [ABSTRACT FROM AUTHOR]

Chitinase-h (Chi-h) is of special interest among insect chitinases due to its exclusive distribution in lepidopteran insects and high sequence identity with bacterial and baculovirus homologs. Here OfChi-h, a Chi-h from Ostrinia furnacalis, was investigated. Crystal structures of both OfChi-h and its complex with chitoheptaose ((GlcN)7) reveal that OfChi-h possesses a long and asymmetric substrate binding cleft, which is a typical characteristics of a processive exo-chitinase. The structural comparison between OfChi-h and its bacterial homolog SmChiA uncovered two phenylalanine-to-tryptophan site variants in OfChi-h at subsites +2 and possibly -7. The F232W/F396W double mutant endowedSmChiA with higher hydrolytic activities toward insoluble substrates, such as insect cuticle, α-chitin, and chitin nanowhisker. An enzymatic assay demonstrated that OfChi-h outperformed OfChtI, an insect endochitinase, toward the insoluble substrates, but showed lower activity toward the soluble substrate ethylene glycol chitin. Furthermore, OfChi-h was found to be inhibited by N,N′,N″-trimethylglucosamine-N,N′,N″,N″′-tetraacetylchitotetraose (TMG-(GlcNAc)4), a substrate analog which can be degraded into TMG-(GlcNAc)1-2. Injection of TMG-(GlcNAc)4 into 5th-instar O. furnacalis larvae led to severe defects in pupation. This work provides insights into a molting-indispensable insect chitinase that is phylogenetically closer to bacterial chitinases than insect chitinases. [ABSTRACT FROM AUTHOR]

Couette flow has been widely used in many industrial and research processes, such as viscosity measurement. For the study on thixotropic viscosity, step-loading, which includes (1) step shear stress and (2) step velocity conditions, is widely used. Transient stages of Couette flow under both step wall shear stress and step wall velocity conditions were investigated. The relative coefficient of viscosity was proposed to reflect the transient process. Relative coefficients of viscosity, dimensionless velocities and dimensionless development times were derived and calculated numerically. This article quantifies the relative coefficients of viscosity as functions of dimensionless time and step ratios when the boundary is subjected to step changes. As expected, in the absence of step changes, the expressions reduce to being functions of dimensionless time. When step wall shear stresses are imposed, the relative coefficients of viscosity change from the values of the step ratios to their steady-state value of 1. But with step-increasing wall velocities, the relative coefficients of viscosity decrease from positive infinity to 1. The relative coefficients of viscosity increase from negative infinity to 1 under the step-decreasing wall velocity condition. During the very initial stage, the relative coefficients of viscosity under step wall velocity conditions are further from 1 than the one under step wall shear stress conditions but the former reaches 1 faster. Dimensionless development times grow with the step ratio under the step-rising conditions and approach the constant value of 1.785 under the step wall shear stress condition, and 0.537 under the step wall velocity condition respectively. The development times under the imposed step wall shear stress conditions are always larger than the same under the imposed step wall velocity conditions. [ABSTRACT FROM AUTHOR]

A MnOx-NbOx-CeO2 catalyst for low temperature selective catalytic reduction (SCR) of NOx with NH3 was prepared by a sol-gel method, and characterized by NH3-NO/NO2 SCR catalytic activity, NO/NH3 oxidation activity, NOx/NH3 TPD, XRD, BET, H2-TPR and in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). The results indicate that the MnOx-NbOx-CeO2 catalyst shows excellent low temperature NH3-SCR activity in the temperature range of 150-300°C. Water vapor inhibits the low temperature activity of the catalyst in standard SCR due to the inhibition of NOx adsorption. As the NO2 content increases in the feed, water vapor does not affect the activity in NO2 SCR. Meanwhile, water vapor significantly enhances the N2 selectivity of the fresh and the aged catalysts due to its inhibition of the decomposition of NH4NO3 into N2O. [ABSTRACT FROM AUTHOR]

Classical eyeblink conditioning (EBC), a simple form of associative learning, has long been served as a model for motor learning and modulation. The neural circuitry of EBC has been studied in detail in rabbits. However, its underlying molecular mechanisms remain unclear. The advent of mouse transgenics has generated new perspectives on the studies of the neural substrates and molecular mechanisms essential for EBC. Results about EBC in mice differ in some aspects from those obtained in other mammals. Here, we review the current studies about the neural circuitry and molecular mechanisms underlying delay and trace EBC in mice. We conclude that brainstem-cerebellar circuit plays an essential role in DEC while the amygdala modulates this process, and that the medial prefrontal cortex (mPFC) as a candidate is involved in the extra-cerebellar mechanism underlying delay eyeblink conditioning (DEC) in mice. We propose the Amygdala-Cerebellum-Prefrontal Cortex-Dynamic-Conditioning Model (ACPDC model) for DEC in mice. As to trace eyeblink conditioning (TEC), the forebrain regions may play an essential role in it, whereas cerebellar cortex seems to be out of the neural circuitry in mice. Moreover, the molecular mechanisms underlying DEC and TEC in mice differ from each other. This review provides some new information and perspectives for further research on EBC. [ABSTRACT FROM AUTHOR]

Thin aluminium sheets have great usage in aircraft manufacturing due to their light weight and high strength. Wrinkling is one of the major defects in the rubber forming of aluminium sheets and may be an obstacle to assembling the parts. In this study, wrinkling was analyzed by shrink flanging in rubber forming process with orthogonal experimental design. Four effect factors (die radius, the flange length, die fillet radius and forming pressure) were analyzed. Three alloy materials (2024-O, 7075-O, 2024-T3) were used as material. The area of wrinkles was introduced to analyze the difference of the effect factors. It was found that different factors had large effect on the wrinkling. The extent of wrinkling of different materials agrees well with their strengths. The best range of the forming pressure is under 300 bar for 2024-O and 7075-O. Wrinkling can be predict using numerical simulation. Three steps forming is a good method to control wrinkling of shrink flange in rubber forming process. [ABSTRACT FROM AUTHOR]