Construction of Uniform LiF Coating Layers for Stable High-Voltage LiCoO2 Cathodes in Lithium-Ion Batteries.

Stabilizing LiCoO2 (LCO) at 4.5 V rather than the common 4.2 V is important for the high specific capacity. In this study, we developed a simple and efficient way to improve the stability of LiCoO2 at high voltages. After a simple sol-gel method, we introduced trifluoroacetic acid (TA) to the surface of LCO via an afterwards calcination. Meanwhile, the TA reacted with residual lithium on the surface of LCO, further leading to the formation of uniform LiF nanoshells. The LiF nanoshells could effectively restrict the interfacial side reaction, hinder the transition metal dissolution and thus achieve a stable cathode-electrolyte interface at high working-voltages. As a result, the LCO@LiF demonstrated a much superior cycling stability with a capacity retention ratio of 83.54% after 100 cycles compared with the bare ones (43.3% for capacity retention), as well as high rate performances. Notably, LiF coating layers endow LCO with excellent high-temperature performances and outstanding full-cell performances. This work provides a simple and effective way to prepare stable LCO materials working at a high voltage.

Strain improvement of Trichoderma harzianum for enhanced biocontrol capacity: Strategies and prospects.

In the control of plant diseases, biocontrol has the advantages of being efficient and safe for human health and the environment. The filamentous fungus Trichoderma harzianum and its closely related species can inhibit the growth of many phytopathogenic fungi, and have been developed as commercial biocontrol agents for decades. In this review, we summarize studies on T. harzianum species complex from the perspective of strain improvement. To elevate the biocontrol ability, the production of extracellular proteins and compounds with antimicrobial or plant immunity-eliciting activities need to be enhanced. In addition, resistance to various environmental stressors should be strengthened. Engineering the gene regulatory system has the potential to modulate a variety of biological processes related to biocontrol. With the rapidly developing technologies for fungal genetic engineering, T. harzianum strains with increased biocontrol activities are expected to be constructed to promote the sustainable development of agriculture.

Machine learning-based ice detection approach for power transmission lines by utilizing FBG micro-meteorological sensors.

Severe icing of transmission lines causes power failures, tower collapses, and other adverse events, which hinders the normal operation of society. Existing icing monitoring methods have problems of irregular monitoring and poor accuracy. In this study, we propose a comprehensive model for predicting hard rime and glaze ice using temperature, humidity, and historical icing data. The results of the experimental verification conducted for nine icing cycles in different years and geographic locations demonstrate that the proposed technique can effectively predict multiple types of icing while ensuring correlation coefficients > 0.99 and mean squared error < 4%.

Structure-guided engineering of transcriptional activator XYR1 for inducer-free production of lignocellulolytic enzymes in Trichoderma reesei.

The filamentous fungus Trichoderma reesei is widely used for the production of lignocellulolytic enzymes in industry. XYR1 is the major transcriptional activator of cellulases and hemicellulases in T. reesei. However, rational engineering of XYR1 for improved lignocellulolytic enzymes production has been limited by the lack of structure information. Here, alanine 873 was identified as a new potential target for the engineering of XYR1 based on its structure predicted by AlphaFold2. The mutation of this residue to tyrosine enabled significantly enhanced production of xylanolytic enzymes in the medium with cellulose as the carbon source. Moreover, xylanase and cellulase production increased by 56.7- and 3.3-fold, respectively, when glucose was used as the sole carbon source. Under both conditions, the improvements of lignocellulolytic enzyme production were higher than those in the previously reported V821F mutant. With the enriched hemicellulases and cellulases, the crude enzymes secreted by the A873Y mutant strain produced 51 % more glucose and 52 % more xylose from pretreated corn stover than those of the parent strain. The results provide a novel strategy for engineering the lignocellulolytic enzyme-producing capacity of T. reesei, and would be helpful for understanding the molecular mechanisms of XYR1 regulation.

Numerical and experimental performance evaluation of a laser-concentrated photovoltaic-thermoelectric generator hybrid system.

Thermal management of concentrated photovoltaic (CPV) modules is essential to avoid the decrease in conversion efficiency caused by temperature rise during their operation. This is even more important for laser-concentrated CPV hybrid systems where out-of-control temperature rise is more likely to happen. In this research, a three-dimensional simulation model for a concentrated photovoltaic-thermoelectric (CPV-TE) hybrid system was studied to optimize its parameters and improve its conversion efficiency under laser radiation. Based on the simulation results, an integrated CPV-TE device was designed, fabricated, and tested under a high-power laser. The novel integrated CPV-TE system utilizes growing electrodes to encapsulate CPV directly on the TEG. Compared to conventional CPV-TE systems that utilize silicone-filled, the integrated CPV-TE system reduces contact thermal resistance and increases output power as well as conversion efficiency. To the best of our knowledge, this is the first study to discuss and optimize a CPV-TE hybrid system for laser radiation. In addition, this research improves the efficiency of laser energy conversion, increases the reliability and stability of the system, and may facilitate the promotion of optical wireless and fiber power transmission systems in future applications.

Customized optimization of lignocellulolytic enzyme cocktails for efficient conversion of pectin-rich biomass residues.

Pectin is a major component in many agricultural feedstocks. Despite the wide use in industrial production of cellulases and hemicellulases, the fungus Trichoderma reesei lacks a complete enzyme set for pectin degradation. In this study, three representative pectinolytic enzymes were expressed and screened for their abilities to improve the efficiency of T. reesei enzymes on the conversion of different agricultural residues. By replacing 5 % of the T. reesei proteins, endopolygalacturonase and pectin lyase remarkably increased the release of sugars from inferior tobacco leaves. In contrast, pectin methylesterase showed the strongest improving effect (by 31.1 %) on the hydrolysis of beetroot residue. The pectin in beetroot residue was only mildly degraded with the supplementation of pectin methylesterase, which allowed the extraction of pectin keeping the original emulsifying activity with a 51.1 % higher yield. The results provide a basis for precise optimization of lignocellulolytic enzyme systems for targeted valorization of pectin-rich agricultural residues.

GPR-based high-precision passive-support fiber ice coating detection method for power transmission lines.

A novel monitoring method based on fiber Bragg grating sensor for detecting the ice coating on power transmission lines is proposed and demonstrated in this study. Sensors are installed on transmission line towers to monitor micrometeorological information and machine learning algorithms based on Gaussian processes use the real-time monitoring results to predict the ice thickness on the lines. The experimental results prove that the mean squared error and mean absolute percentage error values between the predicted and actual values are both less than 1%. This is the first time that only micrometeorological information has been used to monitor ice thickness.

Establishment of pantropic spotted dolphin (Stenella attenuata) fibroblast cell line and potential influence of polybrominated diphenyl ethers (PBDEs) on cytokines response.

The presence of polybrominated diphenyl ethers (PBDEs) in the aquatic environment is an issue of major concern which may be a cause of increasing prevalence and severity of diseases in marine mammals. Although, cell culture model development and in vitro investigation approach is a prime need of time to progress immunotoxic research on aquatic mammals. In this study, we stablished fibroblast cell line (pantropic spotted dolphin) to assess the potential effects of PBDEs on cytokines response. Cells were grown in 6 well cell culture plate and complete media (DMEM and Ham's F12 nutrient mixture, fetal bovine serum, antibiotic and essential amino acids) was provided. The primary culture of (PSP-LWH) cells identification was achieved by vimentin (gene and protein) expressions. Karyotyping revealed pantropic spotted dolphin chromosomes 20 pairs with XX. Transfection was achieved by SV40 LT antigen and transfected cells were expended for passages. Stability of cell line was confirmed at various passages intervals using RT-PCR, western blotting and immunofluorescence methods. After confirmation, cell line was exposed to BDE-47 (250 ng/ml), BDE-100 (250 ng/ml) and BDE-209 (1000 ng/ml), with control group (PBS), positive control DMSO (0.1%) and negative control LPS (500 ng/ml) for 24 h. The ELISA results showed significant increase in IL-6 in BDE- 100 and BDE-209 while IL-1ß and IL-8 were found higher in BDE-47 and BDE-100. TNFα and IL-10 secretion was noted higher in control and positive control groups. Altogether, these results emphasize importance of transfected (PSP-LWHT) cell line in aquatic research and potential effects of PBDEs on fibroblast provides evident to understand immune modulating effects of PBDEs in marine mammals. The impact of PBDEs on dolphin's fibroblast cells immune response and altered cytokine response have been presented for the first time.

Inverse sparse tracker with a locally weighted distance metric.

Sparse representation has been recently extensively studied for visual tracking and generally facilitates more accurate tracking results than classic methods. In this paper, we propose a sparsity-based tracking algorithm that is featured with two components: 1) an inverse sparse representation formulation and 2) a locally weighted distance metric. In the inverse sparse representation formulation, the target template is reconstructed with particles, which enables the tracker to compute the weights of all particles by solving only one l1 optimization problem and thereby provides a quite efficient model. This is in direct contrast to most previous sparse trackers that entail solving one optimization problem for each particle. However, we notice that this formulation with normal Euclidean distance metric is sensitive to partial noise like occlusion and illumination changes. To this end, we design a locally weighted distance metric to replace the Euclidean one. Similar ideas of using local features appear in other works, but only being supported by popular assumptions like local models could handle partial noise better than holistic models, without any solid theoretical analysis. In this paper, we attempt to explicitly explain it from a mathematical view. On that basis, we further propose a method to assign local weights by exploiting the temporal and spatial continuity. In the proposed method, appearance changes caused by partial occlusion and shape deformation are carefully considered, thereby facilitating accurate similarity measurement and model update. The experimental validation is conducted from two aspects: 1) self validation on key components and 2) comparison with other state-of-the-art algorithms. Results over 15 challenging sequences show that the proposed tracking algorithm performs favorably against the existing sparsity-based trackers and the other state-of-the-art methods.