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In the vibration-assisted milling process, the cutting force as a very important parameter can reflect the cutting characteristics of this machining method. In this study, a three-dimensional vibration-assisted milling system was utilized to focus on the changing law of the cutting forces and the topography of the structured surface during machining. Firstly, the kinematic analysis proves that the trajectory of the tool relative to the workpiece under the excitation of the vibration device is a complex spatial spiral curve. Then, many vibration-assisted milling experiments were carried out to investigate the effect of the process variables, such as the spindle speed, feed rate, amplitude of vibration, vibration frequency, and tool radius, on the cutting forces (average and maximum cutting forces) and the topographical characteristics of the structured surfaces. The experimental results sufficiently confirmed that the amplitude of vibration is the most important process variable associated with the cutting forces, followed by spindle speed and vibration frequency; for the topographic features of the structured surface, the amplitude of vibration also has an important effect on the three-dimensional dimensions of each structural unit; by contrast, the vibration frequency and the feed rate do have a significant effect on the topography of structured surfaces. The results of the research provide critical guidance for 3D vibration-assisted milling to fabricate a variety of structured surfaces. [ABSTRACT FROM AUTHOR]

Wax gourd (Benincasa hispida (Thunb.) Cogn., 2n = 2x = 24) is an economically important vegetable crop cultivated widely in many tropical and subtropical regions, including China, India, and Japan. Both fruit and seeds are prized agronomic attributes in wax gourd breeding and production. However, the genetic mechanisms underlying these traits remain largely unexplored. In this study, we observed a strong correlation between fruit size and seed size variation in our mapping population, indicating genetic control by a single gene, BhLS, with large size being dominant over small. Through bulk segregant analysis sequencing and fine mapping with a large F2 population, we precisely located the BhLS gene within a 47.098-kb physical interval on Chromosome 10. Within this interval, only one gene, Bhi10M000649, was identified, showing homology to Arabidopsis HOOKLESS1. A nonsynonymous mutation (G to C) in the second exon of Bhi10M000649 was found to be significantly associated with both fruit and seed size variation in wax gourd. These findings collectively highlight the pleiotropic effect of the BhLS gene in regulating fruit and seed size in wax gourd. Our results offer molecular insights into the variation of fruit and seed size in wax gourd and establish a fundamental framework for breeding wax gourd cultivars with desired traits. [ABSTRACT FROM AUTHOR]

Polyalkylene glycol (PAG) aqueous solutions have recently been demonstrated to exhibit an ultralow friction coefficient (COF, μ < 0.01). However, the prolonged running-in period and low bearing capacity have limited its widespread application. In this study, we determined that the running-in period can be decreased by more than 75% when the pH value of the lubricant is controlled at 3 by introducing various acid solutions. Additionally, less time was required to realize stable superlubricity with inorganic acid at lower pH values. This was mainly attributed to the acceleration effect of hydrogen ions around the contact region. In case of PAG aqueous solution with organic acid, the wear loss between sliding solid surfaces was reduced, and thus the bearing pressure during the superlubricity period was significantly improved from approximately 30 to 160 MPa. Furthermore, the organic acid molecules were considered to form strong hydrogen bonds with PAG macromolecules and solid surfaces. This in turn strengthened the structure of the adsorption layers. The unique effect of different acids in aqueous polymer lubrication can potentially significantly aid in advancing the study of polymer tribology and broadening industrial applications. [ABSTRACT FROM AUTHOR]

Purpose: The complex and elaborate structure of the urinary system presents surgeons with difficulty in using a ureteroscope with a fixed optical fiber to reach the targeted calculus. To address this challenge, a robotic device is required to control the direction of laser irradiation position independently in ureteroscopes. Method: A continuum robotic device was designed and fabricated. The device is constructed with three slackened shape memory alloy (SMA) wires to control the laser irradiation position of the optical fiber combined with the view of the camera on the tip of the ureteroscope. Kinematics analysis and experimental evaluation reveal the capability of the device. Results: The structure of the device is the same as a single-joint continuum robot. This device is unique because of the tiny diameter of 1.1 mm which can be used inside the ureteroscope through a Ø1.2 mm inner channel into the kidney for transurethral ureterolithotripsy. Kinematic analysis revealed the relationship among space coordinates, angles of bending, and direction and SMA wires length. The maximum bending angle was around 25° when the current value was 350 mA on a single SMA wire. The device could achieve multi-directional bending by allocating the values of current on SMA wires, separately. Conclusion: This device offers a major advancement in small size and dexterity in medical robotics. Combined with a proper control system, this device could simplify the operation and improve the efficiency of the transurethral ureterolithotripsy. [ABSTRACT FROM AUTHOR]

A mathematical model of the coupler points generated by the revolute-revolute-spherical-spherical (RRSS) mechanism is established. A characteristic of the projection of feature points is identified by extending preprocessing to the coupler points. Based on this finding, the 16-geometric-parameter design process is divided into three steps. In the first step, a new objective function for optimizing the linkage angle parameters is presented. In the second step, an additional objective function based on the relationship of wavelet coefficients between the mechanism elliptical phase angles and coupler angles is proposed to optimize the linkage length parameters. In the third step, the remaining geometric parameters are calculated based on the relationship between the precision points and coupler points generated by the obtained geometric parameters. Because there are fewer independent variables in each step, the dimensionality reduction synthesis method can yield design solutions with high precision in a short time. Five examples are presented to demonstrate the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]

Hypoxia can cause Epithelial–mesenchymal transition (EMT) in renal tubular cells, and in turn, renal fibrosis. We tested the expression of TRIM46, a member of tripartite motif-containing (TRIM) family proteins, and mesenchymal markers under hypoxia. Our results showed that hypoxia significantly enhanced expression of TRIM46 in HK2 human renal proximal tubular epithelial cells. Our data further showed that hypoxia led to upregulated expression of mesenchymal markers including α-smooth muscle actin, vimentin, and Snail, and downregulated expression of epithelial marker E-cadherin, coupled with an increased abundance of nuclear β-catenin. However, such effects were reversed when TRIM46 expression was knocked down. TRIM46 overexpression had similar effects as hypoxia exposure, and such effects were reversed when cells were treated with XAV-939, a selective inhibitor for β-catenin. Furthermore, we found that TRIM46 promoted ubiquitination and proteasomal degradation of Axin1 protein, a robust negative regulator of Wnt/β-catenin signaling activity. Finally, increased TRIM46 coupled with decreased Axin1 was observed in a rat renal fibrosis model. These data suggest a novel mechanism contributing to EMT that mediates hypoxia-induced renal fibrosis. Our results suggest that selectively inhibiting this pathway that activates fibrosis in human kidney may lead to development of a novel therapeutic approach for managing this disease. [ABSTRACT FROM AUTHOR]

Polyacrylamide (PAAm) hydrogels with brush-covered or crosslinked surfaces were produced and their tribological behavior was studied over a wide range of sliding speeds for two different contact geometries: sphere-on-flat and flat-pin-on-flat. Irrespective of the contact geometry, the brushy hydrogel surfaces displayed up to an order of magnitude lower coefficients of friction μ (COF) compared to the crosslinked surfaces, even achieving superlubricity (μ < 0.01). In general, a hydrogel sphere showed a lower coefficient of friction than a flat hydrogel pin at a similar contact pressure over the entire range of sliding speeds. However, after normalizing the friction force by the contact area, the shear stress of hydrogels with either crosslinked or brushy surfaces was found to be similar for both contact geometries at low speeds, indicating that hydrogel friction is unaffected by the contact geometry at these speeds. At high sliding speeds, the shear stress was found to be lower for a sphere-on-flat configuration compared to a flat-pin-on-flat configuration. This can be attributed to the larger equivalent hydrodynamic thickness due to the convergent inlet zone ahead of the sphere-on-flat contact, which presumably enhances the water supply in the contact, promotes rehydration, and thus reduces the friction at high sliding speeds compared to that measured for the flat-pin-on-flat contact. [ABSTRACT FROM AUTHOR]

Structural optimization based on natural products has become an effective way to develop new fungicides, which provides important guiding significance for practicing the new development concept and promoting the green development of pesticides. In this project, the target compounds containing 4-quinolone and piperazine substructures based on waltherione F were synthesized through the combination of the fungicidal amide lead compound X-I-4 discovered in our previous work and various of fungicidal piperazine derivatives. Screening of their biological activities suggested that products I-3, I-5, II-3, II-7, II-10, II-11 and II-13 displayed higher inhibition rates against Rhizoctonia solani than other tested compounds. The in vitro cellular cytotoxicity assay revealed that compounds II-6 and II-11 exhibited higher cytotoxicity against HepG2 than other tested compounds. The fluorescence characteristics investigation showed that the absolute fluorescence QY value of the methanol solution of the compound I-6 was higher than those of I-2, I-3, I-7 and I-8, which was further elucidated by TD-DFT. [ABSTRACT FROM AUTHOR]

Reactive distillation is a strengthening process, which is widely used for the transesterification of propylene carbonate and methanol to synthesize dimethyl carbonate. In this paper, suitable catalysts of ZrO2–Al2O3 solid solutions were prepared for distillation column. The structure–property correlations were characterized by XRD, XPS, N2 adsorption–desorption, CO2-TPD, and NH3-TPD. The introduction of Al3+ replaced Zr4+ in zirconia forming a homogeneous solid solution, which generated strong basic sites and increased weak acid sites of the catalyst. It has shown excellent catalytic performance for the synthesis of dimethyl carbonate due to the synergistic effects of the acid–base sites. At the same time, the key parameters of the reactive distillation process were studied, and under optimized reaction conditions (feed alcohol ester ratio = 4, reflux ratio = 5:1, height of reaction section = 0.25 m, liquid space velocity of propylene carbonate = 0.26 h−1), the propylene carbonate conversion and selectivity to dimethyl carbonate were 98.14% and 99.96%, respectively. [ABSTRACT FROM AUTHOR]

Drought, one of the crucial environmental constraints, seriously threats the quality and yield in chieh-qua. Therefore, cultivating drought-tolerant variety is greatly necessary for its normal growth under water deficiency. However, at present, molecular knowledge on drought resistance is mostly unclear in chieh-qua. In the study, characteristics of two diverse genetic chieh-qua variety, A39 (drought-resistance) and H5 (drought-sensitivity), were analyzed. Under drought stress, H5 exerted high water loss rate, increased malonaldehyde (MDA) content, and decreased enzyme activity of glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD) compared with A39. In addition, based on the transcriptome results, we obtained a total of 1821 (511 up-regulated and 1310 down-regulated) and 2114 (1282 up-regulated and 832 down- regulated) differentially expressed genes (DEGs) in the A39 versus H5 under normal and water-deficiency stress, respectively. Several DEGs involved in the cuticle synthesis (cytochrome P450 genes: CYP94A2, CYP86B1, CYP86A7), carbohydrate metabolism, and plant hormone signal transduction (small auxin-up RNA genes: SAUR32, SAUR72; JA-induced genes: TIFY 10A, TIFY 10C; ABA related genes: PYL2, PYL4) were explored and related to drought resistance. These expression patterns observed in the RNA-seq data were further confirmed with quantitative real-time PCR (qRT-PCR). In all, these results not only provided a new insight into analyzing genes of drought response, but also laid a foundation for isolating crucial genes involved in drought stress in chieh-qua. [ABSTRACT FROM AUTHOR]

The botanical family Cucurbitaceae includes a variety of fruit crops with global or local economic importance. How their genomes evolve and the genetic basis of diversity remain largely unexplored. In this study, we sequence the genome of the wax gourd (Benincasa hispida), which bears giant fruit up to 80 cm in length and weighing over 20 kg. Comparative analyses of six cucurbit genomes reveal that the wax gourd genome represents the most ancestral karyotype, with the predicted ancestral genome having 15 proto-chromosomes. We also resequence 146 lines of diverse germplasm and build a variation map consisting of 16 million variations. Combining population genetics and linkage mapping, we identify a number of regions/genes potentially selected during domestication and improvement, some of which likely contribute to the large fruit size in wax gourds. Our analyses of these data help to understand genome evolution and function in cucurbits. Cucurbits fruits have diverse shapes and sizes, but their genomes evolution and genetic basis of diversity are unclear. Here, the authors show that the wax gourd genome has the most ancestral karyotype among cucurbits and identify candidate genes which contribute to large fruit size by comparative and population genomics analyses. [ABSTRACT FROM AUTHOR]

The WRKY transcription factors play an important role in plant resistance for biotic and abiotic stresses. In the present study, we cloned 10 WRKY gene homologs ( CqWRKY) in Chieh-qua ( Benincasa hispida Cogn. var. Chieh- qua) using the rapid-amplification of cDNA ends (RACE) or homology-based cloning methods. We characterized the structure of these CqWRKY genes. Phylogenetic analysis of these sequences with cucumber homologs suggested possible structural conservation of these genes among cucurbit crops. We examined the expression levels of these genes in response to fusaric acid (FA) treatment between resistant and susceptible Chieh-qua lines with quantitative real-time PCR. All genes could be upregulated upon FA treatment, but four CqWRKY genes exhibited differential expression between resistant and susceptible lines before and after FA application. CqWRKY31 seemed to be a positive regulator while CqWRKY1, CqWRKY23 and CqWRKY53 were negative regulators of fusaric resistance. This is the first report of characterization of WRKY family genes in Chieh-qua. The results may also be useful in breeding Chieh-qua for Fusarium wilt resistance. [ABSTRACT FROM AUTHOR]

In the era of big data, the rapid development of mobile participatory sensing devices brings the explosive expansion of data, making information overload a serious problem. In this case, a personalized recommendation system on mobile social media appears. Collaborative filtering is the most widely used approach in a recommendation system. Nevertheless, there still exist many problems, such as the serious data sparsity problem and the cold start problem. Existing approaches cannot effectively solve these problems. Most of the existing recommendation approaches are based on single information source and cannot effectively solve the cold start and data sparsity problems. In addition, some approaches proposed to solve data sparsity fail to consider the effects of users' influences and prediction order on recommendation accuracy. Accordingly, from the perspective of increasing the categories of information, the similarity propagation approach based on a heterogeneous network is proposed to ease the cold start problems by improving the similarity calculation method. In addition, to ease the data sparsity problems, we propose a hybrid collaborative filtering approach based on a score prediction graph to finish the user-item score matrix in order. Finally, we conduct validation experiments on the MovieLens dataset. Compared with five state-of-the-art approaches, our approach outperforms them in terms of the performances of mean absolute error, root-mean-square error, recall, and diversity. [ABSTRACT FROM AUTHOR]

Background: Pulmonary fungal disease is an emerging issue in immunocompetent patients, for whom the characteristics are only partially understood. Methods: We conducted a single-center retrospective study of histologically verified pulmonary fungal disease in Eastern China from 2006 to 2014 to understand the demographics, clinical manifestations, therapeutic approaches, and factors associated with prognosis in this population. All cases were diagnosed according to the 2008 European Organization for the Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infection Diseases Mycoses Study Group definition criteria. Results: A total of 112 cases of pulmonary fungal diseases were enrolled (35 proven, 16 probable, 61 possible), and we analyzed the 35 patients with histologically proven pulmonary fungal diseases in this study. The main fungal species identified were Aspergillus (51.4 %), Cryptococcus (22.9 %), and Mucor (2.4 %). Treatment consisted of antifungal therapeutic agents (54.3 %), surgery and postsurgical agents (25.7 %), or surgery alone (14.3 %). The overall crude mortality rate was 14.3 %, and the mortality due to pulmonary fungal infections was 2.9 %. Significant predictors of mortality by univariate analysis were hypoalbuminemia ( P = 0.005), cancer ( P = 0.008), and positive culture ( P = 0.044). Additionally, hypoalbuminemia was the only risk factor for mortality by multivariate analysis ( RR = 7.56, 95 % CI 1.38-41.46). Conclusion: Pulmonary fungal disease in immunocompetent patients, with Aspergillus as the most common identified species, had a prognosis that was influenced by the level of serum albumin. [ABSTRACT FROM AUTHOR]

Thioredoxin-1 (TRX) is a stress-inducible redox-regulatory protein with antioxidative and anti-inflammatory effects. Here we show that the release of histamine from mast cells elicited by cross-linking of high-affinity receptor for IgE (FcεRI) was significantly suppressed in TRX transgenic (TRX-tg) mice compared to wild type (WT) mice. Intracellular reactive oxygen species (ROS) of mast cells stimulated by IgE and antigen was also reduced in TRX-tg mice compared to WT mice. Whereas there was no difference in the production of cytokines (IL-6 and TNF-α) from mast cells in response to 2,4-dinitrophenylated bovine serum albumin (DNP-BSA) stimulation in TRX-tg and WT mice. Immunological status of TRX-tg mice inclined to T helper (Th) 2 dominant in primary immune response, although there was no difference in the population of dendritic cells (DCs) and regulatory T cells. We conclude that the histamine release from mast cells in TRX-tg mice is suppressed by inhibition of ROS generation. As ROS are involved in mast cell activation and facilitate mediator release, TRX may be a key signaling molecule regulating the early events in the IgE signaling in mast cells and the allergic inflammation.Cell Research (2006) 16: 230–239. doi:10.1038/sj.cr.7310031; published online 16 February 2006 [ABSTRACT FROM AUTHOR]

As an important fruit vegetable, fruit-related traits have become one of the breeding hotspots of wax gourd (Benincasa hispida). The fruit traits have an important role on the quality and yield of wax gourd, and QTL mapping of these traits will provide solid basis for fruit character improvement as well as high-yield breeding. In this study, the inheritance of four fruit-related traits, including fruit weight (FW), fruit length (FL), fruit diameter (FD) and flesh thickness (FT), was analyzed. All the frequency distribution of the four traits in an F2 population showed a single peak skewed distribution, which proved them to be quantitative. Subsequently, based on the high-density genetic map using 140 F2 individuals, nine QTLs associated with the four traits were detected on chromosome 3, 4, 5, 6, 9, 10 and 11. Four of the nine QTLs had major effect, which were responsible for more than 10.0% of phenotypic variance. Furthermore, the major QTLs of FW, FD and FT shared similar location intervals, which implied that this location might contain some pleiotropic genes. This is the first report on QTL mapping of quantitative trait in wax gourd, which plays an important role for fine mapping of these important fruit traits. [ABSTRACT FROM AUTHOR]