Time-dependent trapping of pollinators driven by the alignment of floral phenology with insect circadian rhythms

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Video Saliency Detection Using Object Proposals

In this paper, we introduce a novel approach to identify salient object regions in videos via object proposals. The core idea is to solve the saliency detection problem by ranking and selecting the salient proposals based on object-level saliency cues. Object proposals offer a more complete and high-level representation, which naturally caters to the needs of salient object detection. As well as introducing this novel solution for video salient object detection, we reorganize various discriminative saliency cues and traditional saliency assumptions on object proposals. With object candidates, a proposal ranking and voting scheme, based on various object-level saliency cues, is designed to screen out nonsalient parts, select salient object regions, and to infer an initial saliency estimate. Then a saliency optimization process that considers temporal consistency and appearance differences between salient and nonsalient regions is used to refine the initial saliency estimates. Our experiments on public datasets (SegTrackV2, Freiburg-Berkeley Motion Segmentation Dataset, and Densely Annotated Video Segmentation) validate the effectiveness, and the proposed method produces significant improvements over state-of-the-art algorithms

The role of regulatory B cells on hepatocellular carcinoma progression

Poster PresentationCongress Theme: Translating Discoveries into Prevention and CuresPURPOSE: Regulatory B cells (Bregs) play important roles in autoimmune diseases, but their function in hepatocellular carcinoma (HCC) progression remains unclear. This study attempted to unveil the role of Bregs on HCC progression. EXPERIMENTAL DESIGN: This study examined the distribution of intrahepatic B cells and circulating Bregs population at the level of phenotypes as well as functionality in HCC patients. The mechanisms of Bregs regulating liver tumor cells were further explored in a series of in vitro and in vivo functional studies. RESULTS: The percentage of B cells at tumor margin region was significantly higher than that in tumor or non-tumor region. Increased intrahepatic B cells at tumor margin were positively associated with tumor invasive features and more tumor recurrence. Besides, HCC patients had a significant higher percentage of circulating Bregs than healthy people. Increased circulating Bregs were positively correlated with advanced tumor staging, tumor multiplicity and venous infiltration. Next, our in vivo study firstly revealed that human Bregs promoted HCC tumor growth independent of Tregs in SCID mice. The migration of Bregs into tumor in mice was further confirmed by in vivo imaging and histology. Finally, the molecular mechanism of Bregs promoted proliferation and migration of HCC cells was proved by direct cell-cell interaction via CD40/CD154 signaling in vitro. Coculture of Bregs and HCC cells induced CD40/CD154-dependent cytokines secretion. CONCLUSION: Human Bregs promoted HCC growth and invasiveness by interacting with HCC tumor cells through CD40/CD154 signaling pathway. Bregs might be both a prognostic marker and a therapeutic target for HCC.published_or_final_versio

Effect of the filament discharge current on the microstructure and performance of plasma-enhanced magnetron sputtered TiN coatings

© 2017 Elsevier B.V. Titanium nitride (TiN) coatings were synthesized by plasma-enhanced magnetron sputtering (PEMS) on 316L austenitic stainless steel and YG8 cemented carbide substrates. The plasma enhancement process involved the use of hot filaments as additional sources of electrons for the magnetron discharge. The structural, morphology, crystallinity, thickness, abrasion resistance and adhesion of the TiN coatings, as well as the nanohardness and Young's modulus were investigated at different filament discharge currents. The results showed that with increasing discharge current, the deposition rate of the coating decreased, the structural morphology of the TiN coatings became finer and denser and the columnar grain size decreased. The critical load for failure in scratch adhesion tests of the coatings on stainless steel and YG8 substrates were over 22 N and 141 N, respectively. The nanohardness and Young's modulus both improved significantly from 8 GPa and 200 GPa to 38 GPa and 500 GPa, respectively, after the discharge current increased from 6 A up to 12 A. The adhesion and the abrasion resistance of the coating on cemented carbide increased, and those on stainless steel decreased, with increasing filament discharge current. It was found that matching the Young's modulus of the coating to that of the substrate was important to improve the adhesion and abrasion resistance of the coating. The results demonstrate that TiN coatings can be prepared by PEMS at appropriate filament discharge currents, resulting in coatings with uniform thickness, dense structure and high hardness, abrasion resistance and adhesion

Mathematical characterization of ink diffusion and imbibition processes in chromatography paper as a potential biosensing platform

Materials used for biosensor development normally include silicon, glass, and synthetic polymers, however, paper is a practical and cheap option for the reduction of manufacturing costs with a wide range of applications. Paper-based biosensors have been widely produced, yet poorly characterized on the interaction of different type of molecules with its intricate microstructure. In this work, five ink solutions were prepared as model samples to examine their diffusion and imbibition behavior on grade 3MM chromatography paper. Different mathematical models, previously reported for porous matrices, were fitted and results revealed that upward wicking (r2 ≥ 0.90) equations described the experimental data during the initial stage (< 5 s) and yielded similar permeability values to those calculated from the matrix structural properties. The diffusion coefficient was determined up to attaining equilibrium using the diffusion equation in a cylinder element (r2 ≥ 0.90). This study enabled the characterization of the performance from 3MM chromatography paper, by using ink as a surrogate model of small molecules (e.g. mycotoxins) or small colloidal particles

Aptamer–Target–Gold Nanoparticle Conjugates for the Quantification of Fumonisin B1

Fumonisin B1 (FB1), a mycotoxin classified as group 2B hazard, is of high importance due to its abundance and occurrence in varied crops. Conventional methods for detection are sensitive and selective; however, they also convey disadvantages such as long assay times, expensive equipment and instrumentation, complex procedures, sample pretreatment and unfeasibility for on-site analysis. Therefore, there is a need for quick, simple and affordable quantification methods. On that note, aptamers (ssDNA) are a good alternative for designing specific and sensitive biosensing techniques. In this work, the assessment of the performance of two aptamers (40 and 96 nt) on the colorimetric quantification of FB1 was determined by conducting an aptamer–target incubation step, followed by the addition of gold nanoparticles (AuNPs) and NaCl. Although MgCl2 and Tris-HCl were, respectively, essential for aptamer 96 and 40 nt, the latter was not specific for FB1. Alternatively, the formation of Aptamer (96 nt)–FB1–AuNP conjugates in MgCl2 exhibited stabilization to NaCl-induced aggregation at increasing FB1 concentrations. The application of asymmetric flow field-flow fractionation (AF4) allowed their size separation and characterization by a multidetection system (UV-VIS, MALS and DLS online), with a reduction in the limit of detection from 0.002 µg/mL to 56 fg/mL

Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments.

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90%&nbsp;C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90%&nbsp;CL_{s} for Δm_{41}^{2}&lt;13  eV^{2}. Furthermore, the LSND and MiniBooNE 99%&nbsp;C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}&lt;1.6 eV^{2}

Age adjustment in ecological studies: using a study on arsenic ingestion and bladder cancer as an example

<p>Abstract</p> <p>Background</p> <p>Despite its limitations, ecological study design is widely applied in epidemiology. In most cases, adjustment for age is necessary, but different methods may lead to different conclusions. To compare three methods of age adjustment, a study on the associations between arsenic in drinking water and incidence of bladder cancer in 243 townships in Taiwan was used as an example.</p> <p>Methods</p> <p>A total of 3068 cases of bladder cancer, including 2276 men and 792 women, were identified during a ten-year study period in the study townships. Three methods were applied to analyze the same data set on the ten-year study period. The first (Direct Method) applied direct standardization to obtain standardized incidence rate and then used it as the dependent variable in the regression analysis. The second (Indirect Method) applied indirect standardization to obtain standardized incidence ratio and then used it as the dependent variable in the regression analysis instead. The third (Variable Method) used proportions of residents in different age groups as a part of the independent variables in the multiple regression models.</p> <p>Results</p> <p>All three methods showed a statistically significant positive association between arsenic exposure above 0.64 mg/L and incidence of bladder cancer in men and women, but different results were observed for the other exposure categories. In addition, the risk estimates obtained by different methods for the same exposure category were all different.</p> <p>Conclusions</p> <p>Using an empirical example, the current study confirmed the argument made by other researchers previously that whereas the three different methods of age adjustment may lead to different conclusions, only the third approach can obtain unbiased estimates of the risks. The third method can also generate estimates of the risk associated with each age group, but the other two are unable to evaluate the effects of age directly.</p

Structure of hadron resonances with a nearby zero of the amplitude

We discuss the relation between the analytic structure of the scattering amplitude and the origin of an eigenstate represented by a pole of the amplitude.If the eigenstate is not dynamically generated by the interaction in the channel of interest, the residue of the pole vanishes in the zero coupling limit. Based on the topological nature of the phase of the scattering amplitude, we show that the pole must encounter with the Castillejo-Dalitz-Dyson (CDD) zero in this limit. It is concluded that the dynamical component of the eigenstate is small if a CDD zero exists near the eigenstate pole. We show that the line shape of the resonance is distorted from the Breit-Wigner form as an observable consequence of the nearby CDD zero. Finally, studying the positions of poles and CDD zeros of the KbarN-piSigma amplitude, we discuss the origin of the eigenstates in the Lambda(1405) region.Comment: 7 pages, 3 figures, v2: published versio