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Measuring oil concentration in the aquatic environment is essential for determining the potential exposure, risk, or injury for oil spill response and natural resource damage assessment. Conventional analytical chemistry methods require samples to be collected in the field, shipped, and processed in the laboratory, which is also rather time-consuming, laborious, and costly. For rapid field response immediately after a spill, there is a need to estimate oil concentration in near real time. To make the oil analysis more portable, fast, and cost effective, we developed a plug-and-play device and a deep learning model to assess oil levels in water using fluorescent images of water samples. We constructed a 3D-printed device to collect fluorescent images of solvent-extracted water samples using an iPhone. We prepared approximately 1,300 samples of oil at different concentrations to train and test the deep learning model. The model comprises a convolutional neural network and a novel module of histogram bottleneck block with an attention mechanism to exploit the spectral features found in low-contrast images. This model predicts the oil concentration in weight per volume based on fluorescence image. We devised a confidence interval estimator by combining gradient boosting and polymodal regressor to provide a confidence assessment of our results. Our model achieved sufficient accuracy to predict oil levels for most environmental applications. We plan to improve the device and iPhone application as a near-real-time tool for oil spill responders to measure oil in water. [ABSTRACT FROM AUTHOR]

RDX/Al/wax explosives (RDX = cyclotrimethylenetrinitramine; (O2NNCH2)3) were studied in experiments designed to elucidate the effects of Al content and the surrounding medium on the energy output of aluminized explosives. Explosives with Al contents of 0%, 15%, and 30% were compared in water and concrete media. Results indicate that the explosive's bubble energy in water is higher (by 66%–90%) than the expansion energy in concrete. Heat, sound, and other energies in water (0.28–0.84 MJ kg–1) were much lower than that in concrete (1.49–2.81 MJ kg–1). For shock wave energy, the different media have much less impact on shock wave energy, with that in water being only 0.7%–7% higher than in concrete. The test data presented in this paper improve our understanding of how Al and the surrounding medium contribute to the energy output of the explosive, which is of great significance for improving the energy utilization efficiency of aluminized explosives in water and concrete. [ABSTRACT FROM AUTHOR]

OBJECTIVE: In order to solve the problem of image real-time processing and correction for high-speed endoscopic sweptsource optical coherence tomography (SS-OCT), we highly optimize a computer-unified device architecture-based platform and use a field-programmable gate array to summarize the application experience. MATERIALS AND METHODS: We use the Half-Sync/Half-Asyn mode to optimize memory in order to build a high-throughput data thread pool for CPU. We use asynchronous streaming architecture to multiplex multiple threads at high speed to accelerate data processing. At the same time, we design a rotary scanning position information encoding feedback module to suppress image drift, which can realize 25ns logic-timing sequence synchronization control through FPGA 40MHz clock. RESULTS: The maximum complete attainable axial-scan-processing rate (including memory transfer and display of B-scan frames) is 3.52 MHz for a 16-bit pixel depth and A-scans/s of 1024 pixels. To our knowledge, this is the fastest processing rate reported to date with a single-chip graphical processing unit for SS-OCT. Finally, the established high-speed SS-OCT is used to image mouse esophagus and human fingers, and the output images are stable. When the image size is 1024 × 1024 pixels, the real-time imaging rate is 200 frames per second. CONCLUSIONS: This paper develops a real-time image processing and reconstruction technology suitable for high-throughput SS-OCT systems, which can have high-density operation and efficient parallelism, while suppressing highspeed image drift. It lays the foundation for the non-destructive, in vivo, non-staining, fast and convenient early tumor diagnosis of high-speed endoscopic SS-OCT. [ABSTRACT FROM AUTHOR]

To better understand the influence of the aluminum content on the performance of aluminized explosives, experiments in concrete and cylinder tests were performed. Three types of RDX-based aluminized explosives, in which the mass ratio of aluminum content was 0%, 15%, and 30% were considered in this paper. The shock wave pressures of the aluminized explosives in the affected concrete bodies were measured using manganin pressure sensors. The acceleration ability was obtained using a high-speed camera and a rotating mirror streak camera. The peak pressure attenuation characteristics of the explosives with various aluminum contents indicated that a higher aluminum content is associated with a slower peak pressure attenuation of the shock wave. In addition, the results of the cylinder tests and the metal-rod acceleration tests revealed the influence of the aluminum content on the acceleration ability of explosives in three different time periods. The test data presented in this paper verified the relationship between the aluminum content and explosive performance, which is of great significance for optimizing the properties of aluminized explosives. [ABSTRACT FROM AUTHOR]

Elliptical accretion disk models for tidal disruption events (TDEs) have been recently proposed and independently developed by two groups. Although these two models are characterized by a similar geometry, their physical properties differ considerably. In this paper, we further investigate the properties of the elliptical accretion disk of the nearly uniform distribution of eccentricity within the disk plane. Our results show that the elliptical accretion disks have distinctive hydrodynamic structures and spectral energy distributions, associated with TDEs. The soft X-ray photons generated at pericenter and nearby are trapped in the disk and advected around the ellipse because of large electron scattering opacity. They are absorbed and reprocessed into emission lines and low-frequency continuum via recombination and bremsstrahlung emission. Because of the rapid increase of bound–free and free–free opacities with radius, the low-frequency continuum photons become trapped in the disk at large radius and are advected through apocenter and back to the photon-trapping radius. Elliptical accretion disks predict sub-Eddington luminosities and emit mainly at the photon-trapping radius of thousands of Schwarzschild radii with a blackbody spectrum of nearly single temperature of typically about 3 × 104 K. Because of the self-regulation, the photon-trapping radius expands and contracts following the rise and fall of accretion rate. The radiation temperature is nearly independent of BH mass and accretion rate and varies weakly with the stellar mass and the viscosity parameter. Our results are well consistent with the observations of optical/UV TDEs. [ABSTRACT FROM AUTHOR]

Liu and collaborators recently proposed an elliptical accretion disk model for tidal disruption events (TDEs). They showed that the accretion disks of optical/UV TDEs are large and highly eccentric and suggested that the broad optical emission lines with complex and diverse profiles originate in a cool eccentric accretion disk of random inclination and orientation. In this paper, we calculate the radiation efficiency of the elliptical accretion disk and investigate the implications for observations of TDEs. We compile observational data for the peak bolometric luminosity and total radiation energy after peak brightness of 18 TDE sources and compare these data to the predictions from the elliptical accretion disk model. Our results show that the observations are consistent with the theoretical predictions and that the majority of the orbital energy of the stellar debris is advected into the black hole (BH) without being converted into radiation. Furthermore, we derive the masses of the disrupted stars and the masses of the BHs of the TDEs. The BH masses obtained in this paper are also consistent with those calculated with the MBH–σ* relation. Our results provide an effective method for measuring the masses of BHs in large numbers of TDEs to be discovered in ongoing and next-generation sky surveys, regardless of whether the BHs are located at the centers of galactic nuclei or wander in disks and halos. [ABSTRACT FROM AUTHOR]

In the canonical model for tidal disruption events (TDEs), the stellar debris circularizes quickly to form an accretion disc of size about twice the orbital pericentre of the star. Most TDEs and candidates discovered in the optical/ultraviolet have broad optical emission lines with complex and diverse profiles of puzzling origin. Liu et al. recently developed a relativistic elliptical disc model of constant eccentricity in radius for the broad optical emission lines of TDEs and well reproduced the double-peaked line profiles of the TDE candidate PTF09djl with a large and extremely eccentric accretion disc. In this paper, we show that the optical emission lines of the TDE ASASSN-14li with radically different profiles are well modelled with the relativistic elliptical disc model, too. The accretion disc of ASASSN-14li has an eccentricity 0.97 and semimajor axis of 847 times the Schwarzschild radius (r S) of the black hole (BH). It forms as the consequence of tidal disruption of a star passing by a massive BH with orbital pericentre 25 r S. The optical emission lines of ASASSN-14li are powered by an extended X-ray source of flat radial distribution overlapping the bulk of the accretion disc and the single-peaked asymmetric line profiles are mainly due to the orbital motion of the emitting matter within the disc plane of inclination about 26° and of pericentre orientation closely toward the observer. Our results suggest that modelling the complex line profiles is powerful in probing the structures of accretion discs and coronal X-ray sources in TDEs. [ABSTRACT FROM AUTHOR]

Contents Proper HOXA10 expression was essential for endometrial receptivity what was crucial for successful embryo implantation in mammalian. This study confirmed that miR-182 regulated the expression levels of HOXA10 by binding to its 3′ UTR, selectively downregulated HOXA10 in goat endometrial epithelium cells ( gEECs) but not stromal cell ( gESCs) in vitro. However, HOXA10 and miR-182 both up-expressed in the goat endometrium at gestational day 15 (D15) compared with gestational day 5 (D5), suggesting that there were some other factors regulated the expression of HOXA10 during the development of goat endometrium in vivo. What's more, HOXA10 gene silencing ( HOXA10-si RNA) resulted in gEECs apoptosis in vitro, and it regulated the protein levels of oestrogen receptor a ( ERa), progesterone receptor B ( PRb), insulin-like growth factor 1 receptor ( IGF1R), BCL-2, pleiotrophin ( PTN), AKT and p- JNK in gEECs. Furthermore, HOXA10 might regulate the protein levels of endometrial receptivity biomarker genes, including vascular endothelial growth factor ( VEGF), osteopontin ( OPN), cyclooxygenase-2 ( COX-2) and prolactin receptor ( PRLR) in gEECs. In conclusion, miR-182 targeted HOXA10 selectively in EECs in vitro, and HOXA10 played an important role in maintaining the function of EECs in dairy goats. [ABSTRACT FROM AUTHOR]

Several imidazolium-based ionic liquids (ILs) with different anionic characteristics were investigated to determine their denitrogenation performances from the model oil containing indole or quinoline. Experiment results showed that [C4mim]HSO4exhibited an excellent denitrogenation performance, obtaining about 99% N-removal efficiency from the model oils. In addition, removal efficiency of quinoline and indole after five cycles of ionic liquid can reach 98.4% and 96.3%, respectively. The effects of the extraction temperature, time, and IL/oil mass ratio on the denitrogenation process are discussed in detail. [ABSTRACT FROM AUTHOR]

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OBJECTIVE: The aim of this study was to examine the function of tramadol on cell proliferation, migration and invasion in breast cancer cells in vitro, and to evaluate the effect of tramadol in vivo. Further, we explore the mechanism accounting for the role of tramadol on breast cancer cells. MATERIALS AND METHODS: Cell proliferation was detected by the methyl thiazolyl tetrazolium (MTT) assay. Wound healing assay and transwell assay was applied to quantify the migration and invasion ability of MDA-MB-231 cells. The expression of endogenous α2-adrenoceptor and ERK was measured by Western blotting. RESULTS: Tramadol at a clinical dose of up to 2 μM significantly inhibited the proliferation, migration and invasion in a time-dependent manner from day 0 to 28 in vitro. Moreover, tramadol suppressed the growth of xenotransplant tumor in vivo markedly. Furthermore, the protein levels of α2-adrenoceptor and phosphorylated ERK were decreased by tramadol, whereas the expression of total ERK remained unchanged. In addition, downregulation of α2- adrenoceptor by yohimbine could mimic the effect of tramadol treatment. CONCLUSIONS: Collectively, we demonstrated that tramadol could inhibit proliferation, migration and invasion of breast cancers via inactivating α2-adrenoceptor signaling pathway. Our data provide the experimental fundamental for further investigation of the anti-cancer effect of tramadol in breast cancer cells. [ABSTRACT FROM AUTHOR]

The objective of the present study was to explore a predictor of superovulation response on the basis of associations between the number of embryos recovered and gene polymorphism. Variation in the goat LHβ and GnRHR genes was investigated using polymerase chain reaction-single-strand conformational polymorphism and DNA sequencing. Two single nucleotide polymorphisms (SNPs) were identified in the 5'-UTR of LHβ gene (A59C, P1 locus) and in the Exon 2 of GnRHR gene (T177A, P6 locus). At the P1 locus in both breeds, the frequencies of one allele were 0.46 and 0.51, respectively. At the P6 locus, the minor allele frequency was 0.23. Associations of both SNPs with the number of embryos recovered and the corpus luteum number were evaluated in Boer and Shaanbei goat breeds. Association analysis showed that both SNPs had significant (P < 0.05) effects on the number of embryos recovered and corpus luteum number. These results indicate that LHβ and GnRHR genes are potential markers for the number of embryos recovered. The candidate-gene approach could identify genes influencing the superovulatory response. The study was to analyse associations between the number of embryos recovered and polymorphisms of LHβ and GnRHR genes and showed that two SNPs had significant effects on the number of embryos recovered. LHβ and GnRHR genes are potential markers for the number of embryos recovered. [ABSTRACT FROM AUTHOR]

Abstract: Activated hepatic stellate cells (HSCs) possess strong immune inhibitory activity. The present study highlighted the protective role of HSCs in islet transplantation. Recipients were randomly divided into 4 groups: a diabetic group, an HSC-alone group, an islet-alone transplant group, and a cotransplant group. Graft survival was compared among the 4 groups. Serum transforming growth factor β (TGFβ), tumor necrosis factor α, interleukin-1β, and interferon gamma expression levels were measured. The infiltration of lymphocytes was observed via hematoxylin and eosin staining, and immunohistochemical examinations were performed. Results showed that allogeneic HSCs protect islet allografts better than syngeneic HSCs. There was significant prolonged graft survival and a higher level of TGFβ in the cotransplant group (P < .01). The infiltration of lymphocytes in the cotransplant group was notably less than in the islet-alone group (P < .01). The formation of desmin-positive HSC packages was detected in the cotransplant group. In conclusion, allogeneic HSCs can better prolong the survival of islet allografts by stimulating TGFβ expression and forming a biological capsule around the graft. [Copyright &y& Elsevier]

Decision support systems provide critical support to decision makers. These systems are increasingly complex and, as a result, they are very difficult to test because of the lack of an ideal test oracle. Lack of testing may result in poor software quality and wrong decisions being made and, hence, bring serious consequences. In the present study, the authors conduct a case study, where the authors apply a metamorphic testing method to alleviate the oracle problem in testing decision support systems. Experimental results show that metamorphic testing is effective in revealing faults in the absence of an ideal oracle. [ABSTRACT FROM AUTHOR]

This paper deals with the experimental determination of the in-plane mechanical properties of a carbon-epoxy composite laminate in the temperature range of 100°C to 150 °C. Focus has been on the in-plane shear modulus of the laminate. A time-dependent constitutive model for the in-plane shear modulus has been developed. Material constants for the model were derived from the creep compliance of the laminate, obtained experimentally at various temperatures. The results show that the in-plane shear property of the composite laminate is linear viscoelastic within the temperature range and loading level investigated. The constitutive model was validated experimentally. [ABSTRACT FROM AUTHOR]

A scanning laser acoustic microscope (SLAM) is described. The SLAM achieves a resolution of about 10 μm and is capable of imaging subsurface features at depths up to several millimeters, using appropriate reconstruction algorithms. The various components of the apparatus, both acousto-optical and electronic, are described. A major feature of the SLAM is a digital data-acquisition system capable of storing and processing the complex acoustic field in images with 256×256-pixel resolution. An array processor enables most floating-point operations to be completed in a few seconds. Examples of acoustic images obtained from a test sample are presented. [ABSTRACT FROM AUTHOR]

Colloidal CdSe quantum dots (QDs), whose surface traps are controlled with the purification process, are measured with a Z-scan technique using an 80 femtosecond pulse duration laser source. Their two-photon absorption coefficient and refractive index are decreased more than one order of magnitude with the increase of the density of surface traps, indicating that the surface states are involved in the two-photon process. [ABSTRACT FROM AUTHOR]