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• Fringes and spatial shifting noises in DPHs' reconstructed images degrade the reconstruction quality. • The designed FCN uses DPHs generated from the diffraction field as input to produce recoded DPHs as output. • Experimental results show substantial enhancement of reconstruction quality through the proposed recoding method.. Herein, we proposed a method to recode double-phase holograms (DPHs) with a full convolutional neural network (FCN) for alleviating the fringes and spatial shifting noises in that. There are many fringes near the edge of the diffraction field due to the incomplete Fresnel zone plate, and the pixel-by-pixel encoding method of DPH will cause above fringes to appear in the reconstructed image of that as well. Besides, the spatial shifting noises generated during the conversion from complex-amplitude information to pure-phase information will also decrease the reconstruction quality and definition. Depending on the great nonlinear fitting ability of FCN, the proposed method can recode DPHs, alleviating the fringes and removing the spatial shifting noises effectively. Finally, the phase-only holograms with the resolution 2400 × 4096 have been generated in 0.06 s, which have a peak signal to noise ratio (PSNR) of 35.6 dB in the mean reconstruction quality. Optical results showed that compared with the conventional methods, the target images reconstructed by the proposed method have less noise and a higher display quality. [ABSTRACT FROM AUTHOR]

Lipophagy is a vital biological process that maintains the balance of intracellular lipid metabolism in nonalcoholic fatty liver disease (NAFLD). However, the precise regulatory mechanism of RNF186 in hepatic lipophagy is still unclear. This study investigates the roles and mechanisms of RNF186 in the regulation of lipophagy during the development of NAFLD. In this study, we employed RNF186 knockout mice as well as human liver cells and mouse primary hepatocytes (MPHs) to investigate the role and mechanisms of RNF186 in lipophagy during the progression of NAFLD. Additionally, liver specimens from individuals with NAFLD were examined to assess the expression of RNF186 and its associated factors. Here, we provide evidence that depletion of RNF186 enhances lipophagy in hepatocytes of a NAFLD model. Mechanistically, RNF186 acts as an E3 ubiquitin ligase that targets cytoplasmic HMGB1 for lysine 48 (K48)- and K63-linked ubiquitination, leading to its subsequent proteasomal degradation. Importantly, the translocation of HMGB1 from the nucleus to the cytoplasm is responsible for inducing lipophagy in NAFLD samples. Knockdown of HMGB1 significantly reduces the activation of lipophagy and mediates the decrease in lipid accumulation caused by RNF186 depletion in hepatocytes. Furthermore, we find that maintaining the nuclear HMGB1 level and inhibiting its nuclear-cytoplasmic shuttling are critical for the proper function of RNF186 in NAFLD. Additionally, the expression of RNF186 and HMGB1 in human NAFLD samples, along with factors related to lipophagy, suggest that RNF186 may play a similar role in the pathogenesis of human fatty liver. RNF186 deficiency accelerates hepatic lipophagy in NAFLD through the inhibition of ubiquitination and degradation of cytoplasmic HMGB1. Consequently, targeting the RNF186-HMGB1 axis may offer a promising strategy for the prevention and treatment of NAFLD. [Display omitted] • RNF186 regulates hepatic lipophagy in NAFLD. • RNF186 targets cytoplasmic HMGB1 for lysine 48 (K48)- and K63-linked ubiquitination and subsequent proteasomal degradation. • The nucleocytoplasmic translocation of HMGB1 is required for RNF186 function in NAFLD. [ABSTRACT FROM AUTHOR]

• Effects of SR, piston, CR, and split injection were examined on a DFI engine. • ω-pistons led to fewer HT loss and higher ITE for the less flame-head interaction. • Both higher CR and a larger number of injector orifices promoted ITE. • The split injection strategy was effective in reducing MPRR. • No limitations were found when using DFI with high CR and 8 injector orifices. Experiments have shown that ducted fuel injection (DFI) effectively reduces soot emissions from direct-injection diesel engines. Although many computational studies have evaluated DFI's spray development and soot reduction mechanisms in constant volume chambers, only limited computational work on internal combustion engines exists. The DFI duct assembly changes the engine's in-cylinder flow, spray, and combustion development. Therefore, current production engine designs might not be optimal for achieving the best engine performance with DFI. This work conducted an extensive numerical study to evaluate how parameter changes affect DFI performance. The parameters include swirl ratio, piston geometry, compression ratio (CR), number of injector orifices, split injection strategy, and exhaust gas recirculation (EGR) in a heavy-duty diesel engine utilizing DFI. The combustion and soot emission data from the Sandia compression ignition optical research engine were used for model validation. Simulations showed that an increased swirl ratio resulted in more intense jet flame-piston interaction, slowing down the combustion heat release during the late combustion stage and leading to lower indicated thermal efficiency (ITE) due to higher exhaust losses. A piston-bowl design with a reentrant inner piston edge yielded the highest thermal efficiency, due to the reduced cylinder head heat transfer loss. Additional injector orifices led to higher efficiency owing to a more advanced combustion phasing. Nevertheless, the maximum pressure rise rate (MPRR) and oxides of nitrogen (NO x) emissions also increased with the number of injector orifices due to more rapid heat release and higher combustion temperature. Implementation of a split injection strategy combined with a higher EGR rate effectively inhibited the excessive MPRR and NO x formation. In general, the study concluded that DFI is not sensitive to most parameter changes but will benefit from future parameter optimization. [ABSTRACT FROM AUTHOR]

In pursuit of unleashing ammonia's potential in internal combustion engines, an extensive computational study was conducted to explore the effects of two advanced combustion techniques: pre-chamber combustion (PCC) and dual-fuel compression ignition (DF−CI) on a heavy-duty ammonia engine. In the PCC mode, hydrogen was introduced into the pre-chamber (PC) to generate distributed reacting jets, with a small energy fraction of 0.5%. The case featuring a slightly narrower PC throat (diameter of 5.4 mm) yielded the highest indicated thermal efficiency (ITE) of 50.4%, owing to the rapid distribution of reacting jets and advanced combustion phasing. Further increase in hydrogen energy fraction and reduction in throat diameter resulted in a lower ITE because of the enhanced wall heat transfer loss. The DF−CI mode also exhibited significant potential for achieving high efficiency. Through a systemic optimization of parameters such as diesel injection timing, spray included angle, injection pressure, swirl ratio, and piston shape, a significantly enhanced ITE of 50.3% was attained, 7.2% higher than the baseline scenario. The improvement was primarily attributed to the promoted mixing of diesel with air. Among the design parameters, the swirl ratio and spray included angle exhibited the most significant impact on the engine performance. Overall, both the PCC and DF−CI modes were found to yield high ITE and low ammonia emissions. However, because 20% of the diesel energy fraction was utilized to mitigate ammonia slip in the DF−CI mode, notably higher greenhouse gas emissions (carbon dioxide of 96 g/kW-h) were generated than in the PCC mode. In this regard, the ammonia-hydrogen PCC mode should be a more promising solution to achieve zero-carbon emissions for future ammonia engines. • Both PCC and DF−CI methods exhibit the capability to yield high efficiencies. • SA, P inj , and SR had a significant impact on NH 3 -diesel DF−CI. • Optimal pistons for methane and methanol PCC are not for NH 3 –H 2 PCC. • The narrower-throat PC generates more intense reacting jets and higher ITE. • NH 3 –H 2 PCC yields zero CO 2 emissions and requires a small pilot energy. [ABSTRACT FROM AUTHOR]

Immunotherapy has become a highly promising paradigm for cancer treatment. Herein, a chemo-immunotherapy was developed by encapsulating chemotherapeutic drug doxorubicin (DOX) and Toll-like receptor 7 agonist imiquimod (IMQ) in low molecular weight heparin (LMWH)-d- α -tocopheryl succinate (TOS) micelles (LT). In this process, LMWH and TOS were conjugated by ester bond and they were not only served as the hydrophilic and hydrophobic segments of the carrier, but also exhibited strong anti-metastasis effect. The direct killing of tumor cells mediated by DOX-loaded micelles (LT-DOX) generated tumor-associated antigens, initiating tumor-specific immune responses in combination with IMQ-loaded micelles (LT-IMQ). Furthermore, the blockade of immune checkpoint with programmed cell death ligand 1 (PD-L1) antibody further elevated the immune responses by up-regulating the maturation of DCs as well as the ratios of CD8+ CTLs/T reg and CD4+ T eff /T reg. Therefore, such a multifunctional strategy exhibited great potential for inhibiting the growth of orthotopic and metastatic breast cancer. Chemotherapeutic doxorubicin (DOX) and immune adjuvant imiquimod (IMQ) were respectively encapsulated in LT micelles (LT-DOX/LT-IMQ) to initiate tumor apoptosis and anti-tumor immune response. However, the PD-L1/PD-1 axis impairs the T cell responses. Therefore, anti-PD-L1 was combined with LT-DOX/LT-IMQ to relieve the suppression and further promote the anti-tumor responses. fx1 [ABSTRACT FROM AUTHOR]

Abstract This work numerically investigates the detailed combustion kinetics occurring in an optical, reactivity controlled compression ignition (RCCI) engine. Experimental data from the engine combustion network (ECN) relating to spray H and optical RCCI engine spray/combustion were used for model validation. It was found that the RCCI combustion ignition occurred in the squish, bowl rim edge, and downstream of the spray periphery. To provide insight into key reaction pathways, an in-cylinder reaction pathway analysis method was used, and four characteristic RCCI combustion features were selected: (1) initial low temperature heat release (LTHR) from the high-reactivity fuel (n-heptane) on the spray periphery; (2) intense LTHR, where both iso-octane and n-heptane were converted to intermediates (e.g., CH 2 O) through oxygen-related reactions; (3) early stage high temperature heat release (HTHR) with CH 2 O as the core source species; (4) and intense HTHR, characterized by a substantial energy release. Further analysis of the reactive combustion surfaces demonstrated that the interior flame structure was controlled by OH-CO-O 2 combustion kinetics and the exterior was controlled by CH 2 O-HCO (formyl radical) combustion kinetics. In addition, surrounding the reactive surfaces, iso-octane was consumed primarily through decomposition reactions, forming CH 2 O, which further fueled the following high temperature combustion. [ABSTRACT FROM AUTHOR]

Abstract Airborne carbonaceous fine particles, such as soot and biochar, represent a significant fraction of air particulate matter and have received widespread concern due to their health effects. Atmospheric carbonaceous particles can contain high concentration of polycyclic aromatic hydrocarbons (PAHs), and may pose significant health risks when carried into respiratory system from inhalation of particulates. In this study, the bioaccessibility of two PAH compounds, phenanthrene and pyrene, bound to biochar fine particles was assessed by examining their release in two simulated lung fluids: Gamble's solution and artificial lysosomal fluid (ALF). We observed that only 0.47 to 0.75% of biochar-bound PAHs were released in the simulated lung fluids, most likely due to the physical entrapment of PAH molecules in the micropore regimes of biochar, resulting in strong desorption hysteresis, even though apparent desorption equilibrium was reached within 30 min, well within the average clearance time of particulate matter in lung system. The inorganic and organic salts in the simulated lung fluids were found to inhibit the release of PAHs by exerting the pore blockage effect and salting-out effect. Moreover, the low molecular weight organic acids (LMWOAs) in the lung fluids further inhibited PAH release by increasing the micropore volume and surface area of biochar fine particles. When taking into account the inhibited release, the estimated carcinogenic risks of biochar-bound PAHs are typically low, even under extreme conditions wherein both biochar concentrations and PAH loadings on biochar are very high. An important implication is that contaminant bioavailability needs to be taken into account when assessing the risks of the contaminants bound to airborne carbonaceous materials. Graphical abstract Unlabelled Image Highlights • PAHs bound to biochar fine particles show limited release in simulated lung fluids. • Inhibited release of PAHs is attributable to sequestration in micropores. • Inorganic/organic salts in lung fluids further inhibit release of PAHs. • Bioavailability needs to be considered when assessing risks of airborne PAHs. [ABSTRACT FROM AUTHOR]