Multi-objective energy management strategy for fuel cell hybrid electric vehicle based on stochastic model predictive control.

The fuel cell hybrid electric vehicle (FCHEV) has earned great interest among the automotive industry in recent years. However, the power allocation strategy between proton exchange membrane fuel cell (PEMFC) and lithium-ion battery remains a technological challenge. To conquer this problem, a multi-objective predictive energy management strategy (EMS) based on model predictive control (MPC) is proposed in this paper, combined with velocity forecast and driving pattern recognition. The comparative study is conducted to reveal the interaction between each optimization objectives. Simulation results illustrate that the proposed EMS could maintain SOC around reference, reduce fuel consumption by 6.67%, and avoid PEMFC degradation which caused by frequent start-off and rapid load change.

Deletion of ER-retention motif on SARS-CoV-2 spike protein reduces cell hybrid during cell-cell fusion.

BACKGROUND: The novel SARS-CoV-2 has quickly become a global pandemic since the first reported case in December 2019, with the virus infecting millions of people to date. The spike (S) protein of the SARS-CoV-2 virus plays a key role in binding to angiotensin-converting enzyme 2 (ACE2), a host cell receptor for SARS-CoV-2. S proteins that are expressed on the cell membrane can initiate receptor-dependent syncytia formation that is associated with extensive tissue damage. Formation of syncytia have been previously observed in cells infected with various other viruses (e.g., HIV, Ebola, Influenza, and Herpesviruses). However, this phenomenon is not well documented and the mechanisms regulating the formation of the syncytia by SARS-CoV-2 are not fully understood. RESULTS: In this study, we investigated the possibility that cell fusion events mediated by the S protein of SARS-CoV-2 and ACE2 interaction can occur in different human cell lines that mimic different tissue origins. These cell lines were transduced with either wild-type (WT-S) S protein or a mutated variant where the ER-retention motif was removed (Δ19-S), as well as human ACE2 expression vectors. Different co-culture combinations of spike-expressing 293T, A549, K562, and SK-Hep1 cells with hACE2-expressing cells revealed cell hybrid fusion. However, only certain cells expressing S protein can form syncytial structures as this phenomenon cannot be observed in all co-culture combinations. Thus, SARS-CoV-2 mediated cell-cell fusion represents a cell type-dependent process which might rely on a different set of parameters. Recently, the Δ19-S variant is being widely used to increase SARS-CoV-2 pseudovirus production for in vitro assays. Comparison of cell fusion occurring via Δ19-S expressing cells shows defective nuclear fusion and syncytia formation compared to WT-S. CONCLUSIONS: This distinction between the Δ19-S variant and WT-S protein may have downstream implications for studies that utilize pseudovirus-based entry assays. Additionally, this study suggest that spike protein expressed by vaccines may affect different ACE2-expressing host cells after SARS-CoV-2 vaccine administration. The long-term effects of these vaccines should be monitored carefully. Δ19-S mRNA may represent a safer mRNA vaccine design in the future.

Effect of supercapacitors on the operation of an air-cooled hydrogen fuel cell.

One of the greatest challenges associated with efficient energy use in unmanned aerial vehicles (drones) is that of the energy storage systems - more specifically it's weight and capacity. Current hydrogen fuel cell drones have very promising flight durations, but have a low power density thus performing poorly at peak power demands. Supercapacitors are known to have high power densities and respond significantly well to peak power demands. For this research it is desired to evaluate how supercapacitors can affect the operation of an existing hydrogen fuel cell system, when combined. This study will include the evaluation of the viability of a DC-DC converter used to reduce the size (and subsequently, weight) of a supercapacitor bank. It also evaluates whether specified switching of the sources has an effect. Using data generated from the experiment it was determined that the DC-DC converter (with efficiency >94%) reduced the efficiency (by 0.5%) and duration (by 3.8%) of the supercapacitor bank whilst increasing the weight (by 16.7%). It was also seen that the method of selective switching offered no benefit over that of a self-selecting system, where the former obtained 223 s of usability and the latter 365 s. However, comparing all the results it was observed that the addition of a supercapacitor bank allowed for an improvement in energy- and power density, of the hydrogen fuel cell system, from 0.65 Wh/kg to 1.19 Wh/kg and from 69.7 W/kg to 125.7 W/kg, respectively.

Organic matter removal and nitrogen transformation by a constructed wetland-microbial fuel cell system with simultaneous bioelectricity generation.

Microbial fuel cells integrated into constructed wetlands have been previously studied. Nevertheless, their application as a suitable treatment for wastewater is still in the developmental stage. In this context, the aim of this study was to evaluate organic matter removal and nitrogen transformation by a microbial fuel cell integrated into a constructed wetland (CWMFC). To accomplish this, three experimental systems were operated under batch-mode conditions over 170 days: i) one was planted with Schoenoplectus californicus (P-CWMFC); ii) another was unplanted (NP-CWMFC); and iii) the third system did not have any electrodes (CW) and was used as a control. Chemical oxygen demand (COD) removal efficiency ranged between 74-87%, 69-81% and 62-72% for the P-CWMFC, NP-CWMFC and CW systems, respectively, with organic loading rates (OLR) ranging from 4.8 to 7.9 g COD/m2 d. NH4+-N removal efficiency exceeded 98%, 90% and 83% for P-CWMFC, NP-CWMFC and CW, respectively. Wastewater treatment performance was improved due to anaerobic oxidation that occurred on the anodes. Organic matter removal was 18% higher in closed-circuit mode than in open-circuit mode in both integrated systems (P-CWMFC and NP-CWMFC), and these differences were significant (p < 0.05). With respect to the performance of microbial fuel cells, the maximum power density (8.6 mW/m2) was achieved at an organic loading rate of 7.9 g COD/m2 d with an internal resistance and coulombic efficiency of 251â€¯Ω and 2.4%, respectively. The results obtained in this work can provide positive impacts on CW development by enhancing anaerobic degradation without forced aeration.

A Multi-Cell Hybrid Approach to Elevate the Energy Absorption of Micro-Lattice Materials.

Multi-cell hybrid micro-lattice materials, in which the stretching dominated octet cells were adopted as the strengthen phase while the bending dominated body centered cubic (BCC) lattice was chosen as the soft matrix, were proposed to achieve superior mechanical properties and energy absorption performance. Both stochastic and symmetric distribution of octet cells in the BCC lattice were considered. The cell assembly micromechanics finite element model (FEM) was built and validated by the experimental results. Accordingly, virtual tests were conducted to reveal the stress-strain relationship and deformation patterns of the hybrid lattice specimens. Meanwhile, the influence of reinforcement volume fraction and strut material on the energy absorption ability of the specimens was analyzed. It was concluded that the reinforced octet cells could be adopted to elevate the elastic modulus and collapse strength of the pure BCC micro-lattice material. The multi-cell design could lead to strain hardening in the plateau stress region which resulted in higher plateau stresses and energy absorption capacities. Besides, the symmetric distribution of reinforcements would cause significant stress fluctuations in the plateau region. The obtained results demonstrated that the multi-cell hybrid lattice architectures could be applied to tailor the mechanical behavior and plastic energy absorption performance of micro-lattice materials.

Target delivery selective CSF-1R inhibitor to tumor-associated macrophages via erythrocyte-cancer cell hybrid membrane camouflaged pH-responsive copolymer micelle for cancer immunotherapy.

Tumor-associated macrophages (TAMs) is a promising therapeutic target for cancer immunotherapy, while TAMs targeting therapy using nano-sized drug delivery system (NDDS) is a great challenge. To overcome these drawbacks, a novel erythrocyte-cancer cell hybrid membrane camouflaged pH-responsive copolymer micelle (dextran-grafted-poly (histidine) copolymer) was prepared to target deliver a selective CSF-1R inhibitor: BLZ-945 (shorten as DH@ECm) to TAMs for TAMs depletion. The prepared DH@ECm possessed favorable particle size (~190 nm) preferable immune camouflage and tumor homologies targeting characteristic when it was intravenously administrated into blood system. In tumor acidic microenvironment, DH@ECm possessed pH-responsive characteristic and unique "membrane escape effect" to facilitate recognition and internalization by TAMs via dextran-CD206 receptor specific interaction (about 3.9 fold than free drug), followed by TAMs depletion in vitro. For in vivo studies, DH@ECm could reverse tumor immune-microenvironment with the elevation of CD8+ T cells and possess sufficient tumor immunotherapy (inhibition rate: 64.5%). All the in vitro and in vivo studies demonstrated the therapeutical potential of DH@ECm for tumor immunotherapy.

Color-coded Live Imaging of Heterokaryon Formation and Nuclear Fusion of Hybridizing Cancer Cells.

BACKGROUND/AIM: Fusion of cancer cells has been studied for over half a century. However, the steps involved after initial fusion between cells, such as heterokaryon formation and nuclear fusion, have been difficult to observe in real time. In order to be able to visualize these steps, we have established cancer-cell sublines from the human HT-1080 fibrosarcoma, one expressing green fluorescent protein (GFP) linked to histone H2B in the nucleus and a red fluorescent protein (RFP) in the cytoplasm and the other subline expressing RFP in the nucleus (mCherry) linked to histone H2B and GFP in the cytoplasm. MATERIALS AND METHODS: The two reciprocal color-coded sublines of HT-1080 cells were fused using the Sendai virus. The fused cells were cultured on plastic and observed using an Olympus FV1000 confocal microscope. RESULTS: Multi-nucleate (heterokaryotic) cancer cells, in addition to hybrid cancer cells with single-or multiple-fused nuclei, including fused mitotic nuclei, were observed among the fused cells. Heterokaryons with red, green, orange and yellow nuclei were observed by confocal imaging, even in single hybrid cells. The orange and yellow nuclei indicate nuclear fusion. Red and green nuclei remained unfused. Cell fusion with heterokaryon formation and subsequent nuclear fusion resulting in hybridization may be an important natural phenomenon between cancer cells that may make them more malignant. CONCLUSION: The ability to image the complex processes following cell fusion using reciprocal color-coded cancer cells will allow greater understanding of the genetic basis of malignancy.