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Photosynthetic hydrogen induced by Chlamydomonas reinhardtii presents a promising pathway for producing clean and renewable biofuel. Whereas, this process is transient owing to the repression of [FeFe]-hydrogenase by the oxygen co-evolved in photosystem II. Pulsed light is employed to prevent O 2 accumulation and the activation of Calvin-Benson-Bassham cycle for sustainable H 2. While light quality significantly influences photosynthesis, the optimal wavelength for pulsed light-induced H 2 production remains not fully elucidated. Continuous irradiation at 660–670 nm performs poorly in H 2 production due to the activation of PSII, which is responsible for water oxidation. However, in this study, O 2 was removed using a combination of pulsed light and sulfite treatment. Among six light regimes with different wavelengths, pulsed light peaking at 660 nm resulted in the highest photo-H 2 evolution, reaching approximately 180 mL L−1 within three days. This value was 1.4 times higher than that achieved under conventionally white pulsed light. Exposure to 660 nm red pulsed light not only sustained high activity of PSII and hydrogenase but also reduced the gene expression levels of ribulose-1,5-bisphosphate carboxylase/oxygenase and ferredoxin-NADP+ reductase, which was supposed to attenuate the competing effects of CBB cycle. This finding optimizes an efficient light source for pulsed light-induced H 2 production and demonstrates a great potential for refining pulsed light parameters to improve H 2 production in algae in the future. [Display omitted] • The effects of pulsed light wavelengths on H 2 photoproduction were investigated. • Red pulsed light at 660 nm exhibits the highest level of H 2 photoproduction ability. • Red pulsed light at 660 nm maintains the high activity of both PSII and H 2 ase. • Red pulsed light at 660 nm suppresses the activity of CBB cycle. [ABSTRACT FROM AUTHOR]

Recently, extensive research is showing that deep learning has enormous potential in image steganography. However, most steganography methods based on deep learning are not sufficiently invisible. In this paper, a novel end-to-end deep neural network for image steganography based on generative adversarial network (GAN) and discrete wavelet transformation (DWT) is proposed, which can greatly improve the invisibility of the method. Firstly, the cover image is transformed from the RGB domain to the DWT domain to embed information in frequency. Furthermore, a multi-scale attention convolution to fuse different scales of feature information is proposed, which can help the model to find a better location to embed the information. Finally, the fusion module is used to embed the information into the cover image at different modification intensities. In addition, a new Discriminator that compares cover images and stego images in a patch-to-patch way to improve the ability of the Discriminator. We analyze our algorithm from multiple aspects (e.g., security and invisibility) to verify the superior performance of the proposed method. To demonstrate generalization ability, experiments are conducted on three widely used datasets and show the superior performance of our method compared to other steganography methods based on deep learning. • End-to-end deep neural network based image steganography method. • An effective DWT based method to embed information in frequency. • A multi-scale attention convolution is used to find a better embedding location. • A fusion module is used to embed data at different modification intensities. • A new Discriminator that compares cover and stego in a patch-to-patch way. [ABSTRACT FROM AUTHOR]

Currently, deep learning-based video inpainting algorithms can fill in a specified video region with visually plausible content, usually leaving imperceptible traces. Since deep video inpainting methods can be used to maliciously manipulate video content, there is an urgent need for an effective method to detect and localize deep video inpainting. In this paper, we propose a dual-stream video inpainting detection network, which includes a ConvNeXt dual-stream encoder and a multi-scale feature cross-fusion decoder. To further explore the spatial and temporal traces left by deep inpainting, we extract motion residuals and enhance them using 3D convolution and SRM filtering. Furthermore, we extract filtered residuals using LoG and Laplacian filtering. These residuals are then entered into ConvNeXt, thereby learning discriminative inpainting features. To enhance detection accuracy, we design a top-down pyramid decoder that aims at deep fusion of multi-dimensional multi-scale features to fully exploit the information of different dimensions and levels in detail. We created two datasets containing state-of-the-art video inpainting algorithms and conducted various experiments to evaluate our approach. The experimental results demonstrate that our approach outperforms existing methods and attains a competitive performance despite encountering unseen inpainting algorithms. • End-to-end video inpainting detection and localization method. • Two effective residual extraction module to enhance the inpainting artifacts. • A top-down structure for fusing multi-dimensional and multi-scale features. [ABSTRACT FROM AUTHOR]

Dexamethasone (DEX), a synthetic glucocorticoid, exhibited anti-cancer efficacy in pancreatic xenografts derived from patient tumor tissue or cancer cell lines. The aim of this study was to establish pharmacokinetic/pharmacodynamic (PK/PD) models to quantitatively characterize the inhibitory effect of DEX on tumor growth as well as its discrepancy among 3 xenograft models. Data of tumor growth profiles were collected from a patient-derived xenograft (PDX) model in NOD/SCID mice and 2 cell line–derived (PANC-1 and SW1990) xenograft models in BALB/c nude mice. Empirical PK/PD models were developed to establish mathematical relationships between plasma concentration of DEX and tumor growth dynamics after integrating PK parameters extracted from literature. Drug effect in each model was well described by a linear inhibitory function with a potency factor of 4.67, 3.14, and 2.35 L/mg for PDX, PANC-1, and SW1990 xenograft, respectively. Human efficacious doses of DEX were preliminarily predicted through model-based simulation, and 60% tumor growth inhibition at clinical exposure corresponded to a daily dose range of 26-52 mg intravenously. This modeling work quantified the preclinical anti-cancer effect of DEX and demonstrated the feasibility of its medication in pancreatic cancer, which would be conductive to future translational research. [ABSTRACT FROM AUTHOR]

• Advanced FE modeling of cold-formed stainless steel (CFSS) EHS under combined loads. • A parametric study on the CFSS EHS stub-column behavior under combined loading. • Codified design rules and existing CSM for CFSS CHS under combined loading assessed. • Modified CSM and new interaction design curves for CFSS EHS under combined loading. • Reliability analyses for both the current and proposed design methods are presented. This paper aims to investigate the cross-section response of cold-formed stainless steel (CFSS) elliptical hollow sections (EHS) under combined biaxial bending and axial compression. In the present study, an advanced finite element (FE) model was adopted to perform a comprehensive parametric study for CFSS EHS under combined biaxial bending and axial compression, with different stainless steel alloys, as well as a broad range of cross-section sizes, aspect ratios, loading eccentricities and angles. Numerical results obtained from the parametric study were compared with the design strengths calculated by the current design rules in European code EN 1993-1-4, American specification SEI/ASCE 8-02 and Australian/New Zealand standard AS/NZS 4673. In addition, the Continuous Strength Method (CSM) for CFSS circular hollow sections (CHS) under combined actions, was also evaluated for the design of CFSS EHS under combined actions. The comparisons revealed that the current design codes EN 1993-1-4, SEI/ASCE 8-02 and AS/NZS 4673 provided conservative and very scattered predictions for CFSS EHS under combined actions. The existing CSM can provide more accurate predictions than the current design codes (i.e., AS/NZS 4673, EN 1993-1-4 and SEI/ASCE 8-02), but a further improvement is needed. In the present study, a modified CSM is proposed for CFSS EHS under combined actions, which can achieve reliable and accurate design predictions. [ABSTRACT FROM AUTHOR]

Inorganic mercury (Hg2+) is a highly toxic heavy metal in the environment. To date, the impacts of Hg2+ on the development of monocytes, or monopoiesis, have not been fully addressed. The aim of the present study was to investigate the impact of Hg2+ on monopoiesis. In this study, we treated B10.S mice and DBA/2 mice with 10 μM or 50 μM HgCl 2 via drinking water for 4 wk, and we then evaluated the development of monocytes. Treatment with 50 μM HgCl 2 , but not 10 μM HgCl 2 , increased the number of monocytes in the blood, spleen and bone marrow (BM) of B10.S mice. Accordingly, treatment with 50 μM HgCl 2 , but not 10 μM HgCl 2 , increased the number of common myeloid progenitors (CMP) and granulocyte-macrophage progenitors (GMP) in the BM. Functional analyses indicated that treatment with 50 μM HgCl 2 promoted the differentiation of CMP and GMP to monocytes in the BM of B10.S mice. Mechanistically, treatment with 50 μM HgCl 2 induced the production of IFNγ, which activated the Jak1/3-STAT1/3-IRF1 signaling in CMP and GMP and enhanced their differentiation potential for monocytes in the BM, thus likely leading to increased number of mature monocytes in B10.S mice. Moreover, the increased monopoiesis by Hg2+ was associated with the increased inflammatory status in B10.S mice. In contrast, treatment with 50 μM HgCl 2 did not impact the monopoiesis in DBA/2 mice. Our study reveals the impact of Hg on the development of monocytes. [Display omitted] • Hg promotes differentiation of myeloid progenitors to monocytes in B10.S mice. • Hg disturbs the IFNγ-Jak-STAT-IRF1 axis in myeloid progenitors in B10.S mice. • Hg enhances the inflammatory status in B10.S mice. • Hg does not impact monopoiesis in DBA/2 mice. [ABSTRACT FROM AUTHOR]

Highlights • A FE-based method is presented for residual stresses in cold-formed (CF) steel tubes. • The method is applicable to CF tubes of various sectional shapes and material grades. • Main forming operations of CF tubes by the continuous-forming method were modelled. • Residual stresses in cold-formed steel EHS, RHS and SHS were studied. • FE predictions of residual stresses were compared with laboratory measurements. Abstract Residual stresses and plastic strains in steel tubes are induced by their manufacturing processes and play an important role in determining their mechanical and structural behaviour. The manufacturing process of cold-formed steel hollow sections can be divided into four main stages: (1) the coiling and uncoiling of a steel strip, (2) the transverse bending of the uncoiled strip into a circular shape, (3) the welding of the circular tube along the longitudinal strip edges, and (4) the shaping of the welded circular steel tube into a specific cross-sectional shape. In this paper, a finite element-based method is presented for predicting residual stresses and equivalent plastic strains in cold-formed steel hollow sections (including elliptical, square, and rectangular shapes of both normal grade steel and high strength steel). In this method, residual stresses and equivalent plastic strains due to the coiling, uncoiling and transverse bending operations are predicted analytically, and applied as the initial state for the subsequent finite element simulations of both welding and shaping operations. Predictions from this method show satisfying agreement with experimental measurements, which demonstrate the validity of the proposed method. This method can predict the distributions of residual stresses and equivalent plastic strains across the thickness and over the cross section, which are too complex to be measured completely in laboratory. The method provides a tool for investigating the effects of different material and forming parameters on the resulting cold work and structural behaviour. [ABSTRACT FROM AUTHOR]

Highlights • The state-space method is used for modular modeling of HVAC components. • The graph theory is used to depict and analyze the state-space models. • A dynamic model for VAV system is established based on the state-space models. • ARIMA-based predictive PI controller is investigated by the dynamic system model. Abstract To improve the modeling efficiency of HVAC system, the modular models for HVAC components are to be established by using the state-space method in this study. The component modular models are used to establish a dynamic system model for a VAV (variable-air-volume) system, and the dynamic system model has been validated by transient response experiments. As an example of model application, the ARIMA-based predictive PI controller for room temperature has been investigated with the system model, which is shown to have the better control effect than the traditional PI controller, and this has been validated by experiments as well. The work in this study will be of significance to the dynamic modeling and control algorithm study of air conditioning systems. [ABSTRACT FROM AUTHOR]

Emergency measures are effective measures that can be quickly taken in response to heavy air pollution. They not only have an obvious impact on slowing down the accumulation of particulate matter but also have a significant impact on public health and socio-economic development. Therefore, to analyze the effectiveness of emergency measures, one must assess their environmental, health and economic impacts. In this paper, we use exposure-response functions and a city-level computable general equilibrium (CGE) model to do so for China's Jing-Jin-Ji region. We find that the emergency measures implemented in 2019 significantly improve the region's air quality and enhance public health by reducing risk associated with acute bronchitis. Moreover, those emergency measures notably benefit the Jing-Jin-Ji region economically by expanding labor supply, most notably in Beijing and Tianjin. It seems Beijing and Tianjin should compensate industrial cities in Hebei, which enabled the Jing-Jin-Ji region's better air quality but encountered far fewer economic benefits. Handan, Baoding, and Cangzhou are among the cities in Hebei that are expanding employment in manufacturing and service sectors. These results can provide scientific guidance and policy suggestions for government while using emergency measures to combat regional heavy air pollution considering its health and economic benefits. • Evaluating impacts of inter-regional air pollution controls at city level in China. • Overall evaluate environmental, health, and economic impacts of emergency measures. • Emergency measures improve air quality, enhancing public health by reducing risk. • Emergency measures notably benefit the region economically by expanding labor supply. [ABSTRACT FROM AUTHOR]

• Advanced FE model for CF tubular beam-columns under combined loading is presented. • A parametric study on the CF steel EHS beam-column behavior under combined loading. • Effects of key parameters on the column strength of CF steel EHS beam-columns. • New design recommendations for CF steel EHS beam-columns under combined loading. • Reliability analysis for both the current and modified Eurocode-3 design methods. The present study numerically investigated the global instability of cold-formed (CF) steel elliptical hollow section (EHS) members under combined compression and biaxial bending. A finite element (FE) model for CF tubular members under combined compression and biaxial bending was first developed, in which the strength enhancement, geometric imperfection and residual stresses due to roll-forming were incorporated. The FE model was validated against the existing test results. The validated FE model was employed to carry out a parametric study for CF steel EHS members, which covers an extensive range of cross-section geometries, material grades (including both high strength and normal grade steels), member slenderness, loading eccentricities and loading angles. Based on the generated FE data, the application of the current interaction design formulae for steel members under combined loading in EN 1993–1-1, together with the codified slenderness limits for circular hollow section (CHS) under combined loading, were assessed for the design of CF steel EHS members under combined compression and biaxial bending. It can be found that the design formulae in EN 1993–1-1, together with the slenderness limits for CHS, can give very conservative predictions for CF steel EHS members under combined loading. In addition, the influences of different parameters, including the loading eccentricity, loading angle, loading level and the reduction factor for lateral-torsional buckling, on the member behavior were also examined. Finally, new design recommendations are proposed for the design of CF steel EHS members under combined compression and biaxial bending. [ABSTRACT FROM AUTHOR]