3,517 research outputs found

    2D Numerical ISPH Wave Tank for Complex Fluid-Structure Coupling Problems

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    In this paper, we provide a hybrid incompressible Smoothed Particle Hydrodynamics (ISPH) model for fluid-structure interactions. The numerical algorithms include the mirroring treatment of solid boundary, free surface tracking, wave damping using sponge layer and fluid-solid coupling model. The proposed ISPH wave tank is applied to a series of wave-structure coupling problems including the sloshing in a baffled tank, solitary wave impact on an underwater obstacle, water entry of a cylinder and balance dynamics of a floating object. The simulation results demonstrate that the ISPH model provides an accurate simulation technique in various fluid-structure coupling studies

    Enhanced treatment of shale gas fracturing waste fluid through plant-microbial synergism

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    Embargo until February 12, 2022Cost-efficient and environmentally friendly treatment of hydraulic fracturing effluents is of great significance for the sustainable development of shale gas exploration. We investigated the synergistic effects of plant-microbial treatment of shale gas fracturing waste fluid. The results showed that illumination wavelength and temperature are direct drivers for microbial treatment effects of CODCr and BOD5, while exhibit little effects on nitrogen compounds, TDS, EC, and SS removals as well as microbial species and composition. Plant-microbial synergism could significantly enhance the removal of pollutants compared with removal efficiency without plant enhancement. Additionally, the relative abundance and structure of microorganisms in the hydraulic fracturing effluents greatly varied with the illumination wavelength and temperature under plant-microbial synergism. 201.24 g water dropwort and 435 mg/L activated sludge with illumination of 450–495 nm (blue) at 25 °C was proved as the best treatment condition for shale gas fracturing waste fluid samples, which showed the highest removal efficiency of pollutants and the lowest algal toxicity in treated hydraulic fracturing effluents. The microbial community composition (36.73% Flavobacteriia, 25.01% Gammaproteobacteria, 18.55% Bacteroidia, 9.3% Alphaproteobacteria, 4.1% Cytophagia, and 2.83% Clostridia) was also significantly different from other treatments. The results provide a potential technical solution for improved treatment of shale gas hydraulic fracturing effluents.acceptedVersio

    Certain Class of Analytic Functions Based on qq-difference operator

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    In this paper, we considered a generalized class of starlike functions defined by Kanas and R\u{a}ducanu\cite{10} to obtain integral means inequalities and subordination results. Further, we obtain the for various subclasses of starlike functions.Comment:

    ACMiner: Extraction and Analysis of Authorization Checks in Android's Middleware

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    Billions of users rely on the security of the Android platform to protect phones, tablets, and many different types of consumer electronics. While Android's permission model is well studied, the enforcement of the protection policy has received relatively little attention. Much of this enforcement is spread across system services, taking the form of hard-coded checks within their implementations. In this paper, we propose Authorization Check Miner (ACMiner), a framework for evaluating the correctness of Android's access control enforcement through consistency analysis of authorization checks. ACMiner combines program and text analysis techniques to generate a rich set of authorization checks, mines the corresponding protection policy for each service entry point, and uses association rule mining at a service granularity to identify inconsistencies that may correspond to vulnerabilities. We used ACMiner to study the AOSP version of Android 7.1.1 to identify 28 vulnerabilities relating to missing authorization checks. In doing so, we demonstrate ACMiner's ability to help domain experts process thousands of authorization checks scattered across millions of lines of code

    The versatile application of cervicofacial and cervicothoracic rotation flaps in head and neck surgery

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    <p>Abstract</p> <p>Background</p> <p>The large defects resulting from head and neck tumour surgeries present a reconstructive challenge to surgeons. Although numerous methods can be used, they all have their own limitations. In this paper, we present our experience with cervicofacial and cervicothoracic rotation flaps to help expand the awareness and application of this useful system of flaps.</p> <p>Methods</p> <p>Twenty-one consecutive patients who underwent repair of a variety of defects of the head and neck with cervicofacial or cervicothoracic flaps in our hospital from 2006 to 2009 were retrospectively analysed. Statistics pertaining to the patients' clinical factors were gathered.</p> <p>Results</p> <p>Cheek neoplasms are the most common indication for cervicofacial and cervicothoracic rotation flaps, followed by parotid tumours. Among the 12 patients with medical comorbidities, the most common was hypertension. Defects ranging from 1.5 cm × 1.5 cm to 7 cm × 6 cm were reconstructed by cervicofacial flap, and defects from 3 cm × 2 cm to 16 cm × 7 cm were reconstructed by cervicothoracic flap. The two flaps also exhibited versatility in these reconstructions. When combined with the pectoralis major myocutaneous flap, the cervicothoracic flap could repair through-and-through cheek defects, and in combination with a temporalis myofacial flap, the cervicofacial flap was able to cover orbital defects. Additionally, 95% patients were satisfied with their resulting contour results.</p> <p>Conclusions</p> <p>Cervicofacial and cervicothoracic flaps provide a technically simple, reliable, safe, efficient and cosmetic means to reconstruct defects of the head and neck.</p

    Plastome phylogenomics and morphological traits analyses provide new insights into the phylogenetic position, species delimitation and speciation of Triplostegia (Caprifoliaceae)

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    Background The genus Triplostegia contains two recognized species, T. glandulifera and T. grandifora, but its phylogenetic position and species delimitation remain controversial. In this study, we assembled plastid genomes and nuclear ribosomal DNA (nrDNA) cistrons sampled from 22 wild Triplostegia individuals, each from a separate population, and examined these with 11 recently published Triplostegia plastomes. Morphological traits were measured from herbarium specimens and wild material, and ecological niche models were constructed. Results Triplostegia is a monophyletic genus within the subfamily Dipsacoideae comprising three monophyletic species, T. glandulifera, T. grandifora, and an unrecognized species Triplostegia sp. A, which occupies much higher altitude than the other two. The new species had previously been misidentifed as T. glandulifera, but difers in taproot, leaf, and other characters. Triplotegia is an old genus, with stem age 39.96Ma, and within it T. glandulifera diverged 7.94Ma. Triplostegia grandifora and sp. A diverged 1.05Ma, perhaps in response to Quaternary climate fuctuations. Niche overlap between Triplostegia species was positively correlated with their phylogenetic relatedness. Conclusions Our results provide new insights into the species delimitation of Triplostegia, and indicate that a taxonomic revision of Triplostegia is needed. We also identifed that either rpoB-trnC or ycf1 could serve as a DNA barcode for Triplostegi

    Vision-related Quality of Life and Emotional Impact in Children with Strabismus: a Prospective Study

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    The potential impact of the surgical correction of strabismus on vision-related quality of life (VRQOL) and the symptoms of anxiety and depression in children with strabismus remain unclear. The present study included 60 children with strabismus: 30 with heterophoria and 30 with heterotropia. A healthy age- and gender-matched control group (n = 60) was also recruited. The psychological instruments that were used were the short-form 25-item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) and the Hospital Anxiety and Depression Scale (HADS). The results demonstrated that eight of the 12 NEI-VFQ-25 subscales were significantly impaired in children with strabismus compared with matched controls. Compared with pre-operative values, significant improvements were noted after surgery in the NEI-VFQ-25 summary score, and the anxiety and depression scores. This study demonstrated that the NEI-VFQ-25 instrument can be used in strabismus children and that surgical interventions can improve VRQOL, anxiety and depression in strabismus patients
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