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Reaching the full potential of solar cells based on photo‐absorbers of organic‐inorganic hybrid perovskites requires highly efficient charge extraction at the interface between perovskite and charge transporting layer. This demand is generally challenged by the presence of under‐coordinated metal or halogen ions, causing surface charge trapping and resultant recombination losses. These problems can be tackled by introducing a small molecule interfacial anchor layer based on dimethylbiguanide (DMBG). Benefitting from interactions between the nitrogen‐containing functional groups in DMBG and unsaturated ions in CH3NH3PbI3 perovskites, the electron extraction of TiO2 is dramatically improved in association with reduced Schottky–Read–Hall recombination, as revealed by photoluminescence spectroscopy. As a consequence, the power conversion efficiency of CH3NH3PbI3 solar cells is boosted from 17.14 to 19.1 %, showing appreciably reduced hysteresis. The demonstrated molecular strategy based on DMBG enables one to achieve meliorations on key figures of merit in halide perovskite solar cells with improved stability. Surface traps: Incorporating a dimethylbiguanide (DMBG) anchoring layer in between the compact TiO2 and perovskite photo‐absorber leads to an effective passivation of surface traps with reduced Shockley–Read–Hall recombination, such that the power conversion efficiency of CH3NH3PbI3 solar cells is boosted to 19.1 %. [ABSTRACT FROM AUTHOR]

The vast coastline provides Canada with a flourishing seafood industry including bivalve shellfish production. To sustain a healthy bivalve molluscan shellfish production, the Canadian Shellfish Sanitation Program was established to monitor the health of shellfish harvesting habitats, and fecal coliform bacteria data have been collected at nearly 15,000 marine sample sites across six coastal provinces in Canada since 1979. We applied Functional Principal Component Analysis and subsequent correlation analyses to find annual variation patterns of bacteria levels at sites in each province. The overall magnitude and the seasonality of fecal contamination were modelled by functional principal component one and two, respectively. The amplitude was related to human and warm-blooded animal activities; the seasonality was strongly correlated with river discharge driven by precipitation and snow melt in British Columbia, but such correlation in provinces along the Atlantic coast could not be properly evaluated due to lack of data during winter. • Sparse fecal pollution data were collected across ~15,000 sites along Canada's coast. • Longitudinal geospatial distributions of bacterial levels over decades were studied. • Functional Principal Component Analysis revealed two major annual patterns. • Human and wild-life activities related to the geospatial bacterial amplitudes. • River discharge and precipitation related to the temporal changes of fecal bacteria. [ABSTRACT FROM AUTHOR]

Isoquercitrin of great pharmaceutical value can be transformed from plant-derived rutin by the key enzyme α - L -rhamnosidase. However, the disposable hydrolyzation process and the unsatisfactory properties of α - L -rhamnosidase limit the production of isoquercitrin. In this study, we obtained a mutant of GH78 family RhaB1, RhaB1-ΔN, with improved thermostability and catalytic activity by deleting the domain N. Concretely speaking, the T 50 for 30 min and melting temperature (T m) raised 5.0 °C and 6.2 °C compared with those of RhaB1. Meanwhile, the specific activities were 103 %, 44 %, and 74 % higher than those of the wild type with pNPR, rutin, and naringin as substrates, respectively. With RhaB1-ΔN as a whole-cell catalyst, conversion of isoquercitrin reached 96.6 % within 1.5 h, 8.5 h less than that for free RhaB1. In the 6th recovery, the yield of whole-cell catalyst reached 62.3 % of the maximum, 18.9 times that of the free enzyme (3.3 %). The combined strategies of enzyme modification and whole-cell catalyst helped to realize more recyclable and efficient isoquercitrin production. [Display omitted] • The catalytic efficiency and thermostability of RhaB1 are enhanced by removing its domain N. • The domains D, E, and C of RhaB1 are required for its catalytic activity. • Removal of domain N improves the enzyme's binding to the substrate. • The whole-cell catalyst retained > 60 % activity after six repeated use. • Isoquercitrin yield reached 96.6 % within 1.5 h for the truncated enzyme. [ABSTRACT FROM AUTHOR]

• The pre-crack initiates anew when the horizontal distance between the moving crack and the semicircular arc pre-crack is small. When the distance increases to 8.33 mm, the crack no longer penetrates the semicircular arc pre-crack, and the pre-crack attracts the crack first and then repels it. When d = 11.67 mm, the pre-crack has no considerable effect on the moving crack. • The crack deflection angle and the horizontal offset distance of the two groups of experiments conform to a linear function. • Setting the semicircular arc pre-crack outside the protected medium can effectively protect the medium from impact load. When the moving crack is outside the arc, the medium inside the arc pre-cracks are in the stress relief zone, which can be well protected. In this paper, a plexiglass (PMMA) specimen is designed for dynamic impact testing based on the digital laser dynamic caustics experimental system. The impact of offset distance on dynamic fracture behavior of PMMA specimens with semicircular arc pre-cracks in two different directions is investigated. Research shows that: the pre-crack initiates anew when the horizontal distance between the moving crack and the semicircular arc pre-crack is small. With the increase of horizontal distance, the pre-crack attracts the crack first and then repels it. When the distance reaches a critical threshold, the pre-crack has no considerable effect on the moving crack. The above conclusions are not affected by the direction of the semicircular arc pre-crack. Furthermore, the crack deflection angle and the horizontal offset distance of the two groups of experiments conform to a linear function. When the horizontal offset distance is small, the middle part of the pre-crack initiates again. When the moving crack is outside the arc pre-crack, the medium in the pre-crack is the stress relief zone, according to the numerical data. The ability of the medium to resist impact damage can be effectively boosted by placing acceptable pre-cracks on the medium's periphery. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient bagasse biorefinery with low energy consumption was realized. • A thermostable xylanase mutant was engineered for catalysis under mild conditions. • Seawater following steam explosion promotes the enzymatic hydrolyzation of bagasse. • Synergistic hydrolysis of high activity xylanase and cellulase was optimal. Lignocellulosic biorefining for producing biofuels poses technical challenges. It is usually conducted over a long time using heat, making it energy intensive. In this study, we lowered the energy consumption of this process through an optimized enzyme and pretreatment strategy. First, the dominant mutant M137E/N269G of Bispora sp. MEY-1 XYL10C_ΔN was obtained by directed evolution with high catalytic efficiency (970 mL/s∙mg) and specific activity (2090 U/mg) at 37 °C, and thermostability was improved (T 50 increased by 5 °C). After pretreatment with seawater immersion following steam explosion, bagasse was co-treated with cellulase and M137E/N269G under mild conditions (37 °C), the resulting highest yield of fermentable sugars reached 219 µmol/g of bagasse, 46% higher than that of the non-seawater treatment group, with the highest degree of synergy of 2.0. Pretreatment with seawater following steam explosion and synergistic hydrolysis through high activity xylanase and cellulase helped to achieve low energy degradation of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

The article offers information about a study on the inhibition of propolis on the production of alpha-hemolysin by Staphylococcus aureus. It informs that alpha-hemolysin and messenger-RNA expression under sub inhibitory concentration of propolis changes. The study reveals that the different concentration of propolis can reduce the production of virulence factors alpha-toxins and propolis can inhibit the expression of alpha-hemolysin.

In this study we investigated the antimicrobial activity of magnolol on Staphylococcus aureus. The minimal inhibitory concentrations of magnolol against 31 S. aureus strains ranged from 4-32 μg/mL. In addition, hemolysin assays, Western blotting, and real-time RT-PCR were performed to investigate the effect of magnolol on α-toxin secretion by both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The results indicated that sub-inhibitory concentrations of magnolol dosedependently inhibited the transcription of hla (the gene encoding α-toxin) in S. aureus, resulting in a reduction of α-toxin secretion and, thus, hemolytic activities. [ABSTRACT FROM AUTHOR]

In recent years, microfluidic bioreactors have become important in chemical production; however, the production cost is high, and it becomes difficult to balance scale, efficiency, and cost. Therefore, a low-cost, efficient, high-delivery-capacity, green-fluid reactor is urgently required. Herein, a cellulose bioreactor with dual-scale directional channels and a porous inner wall is reported for the continuous catalytic conversion of polydatin into resveratrol. The dual-scale directional channel structure endows the reactor with high mass transfer speed and large transport capacity, resulting in fast fluid diffusion rate and more severe "disturbance" inside the reactor. It accelerates the mass transfer state of the whole reaction and further improves the catalytic performance compared to the uniform channel reactor. The reactor can achieve a high conversion rate of 98.58% of resveratrol within 2 h and exhibits excellent stability, owing to which it has broad application prospects in catalytic reactions, and helps derive a new approach for constructing fluid catalysis bioreactors. [ABSTRACT FROM AUTHOR]

The article presents a study on the effects of saikosaponin-a on gene transcriptional expression spectrum in Staphylococcus aureus. The study shows that minimum inhibition concentrations (MICs) of saikosaponin-a against 33 S. Aureus strains ranged from 1 to 32 milligrams. The GeneChip analysis illustrated that saikosaponin-a may affect different pathway virulence genes.

The growing preference for incorporating microbial aspartic proteases in industries is due to their high catalytic function and high degree of substrate selectivity. These properties, however, are attributable to molecular alterations in their structure and a variety of other characteristics. Molecular tools, functional genomics, and genome editing technologies coupled with other biotechnological approaches have aided in improving the potential of industrially important microbial proteases by addressing some of their major limitations, such as: low catalytic efficiency, low conversion rates, low thermostability, and less enzyme yield. However, the native folding within their full domain is dependent on a surrounding structure which challenges their functionality in substrate conversion, mainly due to their mutual interactions in the context of complex systems. Hence, manipulating their structure and controlling their expression systems could potentially produce enzymes with high selectivity and catalytic functions. The proteins produced by microbial aspartic proteases are industrially capable and far-reaching in regulating certain harmful distinctive industrial processes and the benefits of being eco-friendly. This review provides: an update on current trends and gaps in microbial protease biotechnology, exploring the relevant recombinant strategies and molecular technologies widely used in expression platforms for engineering microbial aspartic proteases, as well as their potential industrial and biotechnological applications. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the requirements of environmental, cost and economic sustainability, new sources of alternative proteins in the livestock industry are receiving increasing attention. Mulberry (Morus alba L.) leaves are a unique feed resource because of their high protein content and large availability. Therefore, mining sustainable protein suitable for the animal husbandry industry in sericulture resources could achieve a win–win situation. RESULTS: The protein content in mulberry leaves is 232.10–386.16 g kg−1, and the mean value of crude fat content is 43.76 ± 8.48 g kg−1, which has the advantages of protein content and energy. In addition, the average content of phytic acid in mulberry leaves is only 1.88 ± 0.56 g kg−1, which means that it is not inhibited in terms of nutrient absorption. Meanwhile, the digestibility of protein was Bean pulp > Sample 8 ≈ Alfalfa ≈ Sample 13 ≈ Cottonseed meal > Fish meal, and the β‐turn and particle size of mulberry leaf protein are more conducive to digestion in vitro. Furthermore, the protein of Sample 13 had the richest essential amino acids (252.00 g kg−1) and the highest essential amino acid index (EAAI), which was superior to conventional feed protein. In addition, the partial substitution of mulberry leaf protein (15%) significantly increased the EAAI value of conventional feed protein. However, to balance nutrition, it is necessary to combine mulberry leaf protein with other proteins to further broaden its application field. CONCLUSION: Mulberry leaves are a new source of feed protein, which helps to alleviate the two major problems of mulberry resource surplus and feed protein resource shortage. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

According to the traditional blasting theory and practice, the slotted cartridge blasting can form straight cracks extending along the slot direction and achieve directional fracture. In this paper, an experimental study has been carried out to determine the influence of incident stress waves and reflected stress waves. Under the influence of stress waves, the propagation path of the main crack in slotted cartridge blasting is not straight, and the directional fracture effect is inadequate. Under the experimental conditions in this paper, the propagation of main cracks mainly experienced three stages: directional propagation stage, counterclockwise deflecting propagation stage, and clockwise deflecting propagation stage. The difference between incident stress waves and reflected stress waves results in the difference in the deflecting direction, transforming the main crack into a wing shape. In rock roadway drilling and blasting engineering, the propagation path of main cracks produced by peripheral boreholes using the slotted cartridge blasting is also affected by the incident and reflected stress waves. These stress waves are inevitably generated from free faces and adjacent boreholes; however, these are rarely considered in the design of blasting parameters. Therefore, the design and optimization of blasting parameters considering the interaction of stress waves and main cracks in the slotted cartridge blasting need to be further developed. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the control mechanism of blasting damage to surrounding rock and conducts a quantitative evaluation of the damage using laboratory experimentation and field test. A comprehensive evaluation system of blasting damage for roadway contour quality and internal damage of surrounding rock is established using digital image processing, multifractal spectrum calculation, CT scanning, borehole televiewer, and acoustic testing. The results show that the evolution of blasting damage conforms with fractal law, and the relationship between blasting damage area and fractal dimension follows a power function. Slit charge blasting causes the initiation and propagation of two straight main cracks along the slit. The peak velocity measured at the center of the slit charge is found to be 1.74 times that of the ordinary charge. The slit charge can effectively reduce the blasting damage. [ABSTRACT FROM AUTHOR]

Silkworm pupae, by-product of sericulture industry, is massively discarded. The degradation rate of silkworm pupae protein is critical to further employment, which reduces the impact of waste on the environment. Herein, magnetic Janus mesoporous silica nanoparticles immobilized proteinase K mutant T206M and Mucor circinelloides aspartic protease were employed in the co-degradation. The thermostability of T206M improved by enhancing structural rigidity (t 1/2 by 30 min and T 50 by 5 °C), prompting the degradation efficiency. At 65 °C and pH 7, degradation rate reached the highest of 61.7%, which improved by 26% compared with single free protease degradation. Besides, the immobilized protease is easy to separate and reuse, which maintains 50% activity after 10 recycles. Therefore, immobilized protease co-degradation was first applied to the development and utilization of silkworm pupae resulting in the release of promising antioxidant properties and reduces the environmental impact by utilizing a natural and renewable resource. [Display omitted] • A novel approach for co-degrading silkworm pupae protein with Prok and MCAP was developed. • Prok mutant with improved pH and heat stability for co-degradation of silkworm pupae protein. • Mutant activity was maintained with improved thermostability (t 1/2 by 30 min and T 50 by 5 °C). • Silkworm pupae protein degradation rate was improved by 26% compared to single free Prok. • Antioxidant capacity of peptides was improved by 20% and 100% compared to Prok and CA. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel scheme for efficient conversion of flavonoid glycosides by biofilms was developed. • Gene regulation and carrier modification are promising strategies to enhance biofilm catalysis. • The biomass of biofilms from csg D overexpressed strain significantly increased by 79.35 %. • The biofilms adhesion of E. coli in strong oxidant modified carrier was increased by 105.80 %. • The catalytic efficiency of E. coli biofilms enhanced bi-directional was increased by 247.85 %. The biofilm of an engineered strain is limited by slow growth and low yield, resulting in an unsatisfactory ability to resist external stress and promote catalytic efficiency. Here, biofilms used as robust living catalysts were manipulated through dual functionalized gene regulation and carrier modification strategies. The results showed that gene overexpression regulates the autoinducer-2 activity, extracellular polymeric substance content and colony behavior of Escherichia coli , and the biofilm yield of csg D overexpressed strains increased by 79.35 % compared to that of the wild type strains (p < 0.05). In addition, the hydrophilicity of polyurethane fibres modified with potassium dichromate increased significantly, and biofilm adhesion increased by 105.80 %. Finally, the isoquercitrin yield in the catalytic reaction of the biofilm reinforced by the csg D overexpression strain and the modified carrier was 247.85 % higher than that of the untreated group. Overall, this study has developed engineered strains biofilm with special functions, providing possibilities for catalytic applications. [ABSTRACT FROM AUTHOR]

TEC induced on the top of PCBM have been studied as the cathode-interfacial layer (CIL) and the CIL/perovskite interface is modified with a well-matched energy band alignment and suppressed defects. Enhanced power conversion efficiency with negligible hysteresis is obtained for planar perovskite solar cells. • A seamless PCBM@TEC capped perovskite film for the inverted planar PSCs. • PCBM@TEC CIL induced obvious efficiency enhancement for inverted PSCs. • Non-encapsulated devices based on the hydrophobic PCBM@TEC CIL improved stability of planar PSCs. • These improvements in performance and stability highlight the merit of using PCBM@TEC as interfacial layer in planar PSCs. Among the factors that lead to the reduction of the efficiency and stability of perovskite solar cells (PSCs) using [6,6]-phenyl C61 butyric acid methyl ester (PCBM) versus those of conventional structure, is the difficulty involved in realizing a high-quality film, and the non-radiative recombination that takes place at the interface between PCBM and perovskite. Our present work proposes a fabrication technique capable of overcoming these issues. Organic small molecule material was introduced along with PCBM, to obtain a homogeneously seamless film that plays the role of a dipole layer. The incorporated triethyl citrate (TEC) boosts the power conversion efficiency (PCE) from 14.56% to 17.86% with suppressed hysteresis, which originates primarily from the efficient electron transfer between the perovskite/PCBM and the Ag cathode interface. The results of electrochemical impedance spectroscopy measurements imply efficient electron transfer, low series resistance, and large recombination resistance in the photovoltaic device employing PCBM@TEC as the cathode interfacial layer. Specifically, the highly hydrophobic PCBM@TEC cathode interfacial layer (CIL) showed higher resistance to moisture, leading to a more environmentally-stable device. The results also showed the efficiency of the device retained 84% of its initial value after 30 days of operation under ambient conditions, which shows a visibly superior stability compared to a reference device that, under the same environment, retained only 37% its initial efficiency. Such advancement in the operational efficiency and stability of the device, will contribute to the longevity and cost-effectiveness of inverted PSC devices. [ABSTRACT FROM AUTHOR]

Lung cancer (LC) is a serious disease with high morbidity and mortality. Long noncoding RNAs (lncRNAs) have garnered attention because they participate in diverse human disorders, including cancer. Our study examined the long intergenic noncoding RNA 00707 (LINC00707). The effects of LINC00707 on lung adenocarcinoma (LAD) and molecular mechanisms are unclear. This study is aimed to investigate the role of LINC00707 in the malignant processes of LAD. Methods: Quantitative reverse transcription PCR (qRT-PCR) was used to examine the expression level of LINC00707 in tissues and cell lines. The association of LINC00707 expression and postoperative prognosis was analyzed by the Kaplan-Meier method and log-rank test. Cell proliferation was evaluated in vitro and in vivo. Transwell assays were performed to examine cell migration. Cell cycle and apoptosis was determined by flow-cytometric and western blot analyses. Microarray analysis was conducted to screen for the downstream target gene Cdc42 of LINC00707, which was identified by qRT-PCR, functional analysis, and rescue experiment. Results: The expression level of LINC00707 was clearly upregulated in LAD tissues compared to that in corresponding normal tissues. Its overexpression was related to advanced TNM stage, larger tumor size, lymphatic metastasis, and poor prognosis. Functional assays revealed that LINC00707 knockdown repressed LAD cell proliferation both in vitro and in vivo. This process may involve the inducing of G1 arrest and apoptosis. Moreover, cell migration was impaired after LINC00707 inhibition. Microarray analysis and rescue assays suggested that Cdc42 is an important target gene involved in the carcinogenesis of LINC00707. Conclusions: In summary, LINC00707 is a noncoding oncogene that exerts important regulatory functions in LAD, suggesting its potential as a biomarker in the prognosis and treatment of LAD. [ABSTRACT FROM AUTHOR]

Efficient hydrolysis of pectic materials to sugars requires the synergistic action of endo- and exo-polygalacturonases. Two novel polygalacturonases (exo- Te PG28a and endo- Te PG28b) were identified in Talaromyces leycettanus JCM12802, overexpressed in Pichia pastoris , and characterized in this report. The specific activities of Te PG28a and Te PG28b towards polygalacturonic acid were 280 ± 9 and 25,900 ± 502 U/mg, respectively. Both enzymes exhibited optimal activities at pH 3.5 and retained highly stable over a broad pH range of 2.0–7.0. Distinct from most fungal polygalacturonases that have low temperature optima, Te PG28a and Te PG28b were optimally active at 70 °C. When treated the grape juice with the enzyme combination (the unit ratio of Te PG28a: Te PG28b was 1:4), higher pectin-degrading efficiency (up to 140%) was achieved, and light transmittance was improved from 14% to 82%. These favorable enzymatic properties make Te PG28a and Te PG28b attractive for the applications in the juice industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new enzyme-assisted aqueous extraction with CNPs@Cu-Trypsin (CAE) was proposed. • Catalytic reinforcement of Cu2+ on the trypsin immobilized on CNPs was firstly revealed. • Hydrolysis activity and K cat / K m value of the new catalyst was increased by 6.16 and 1.7 times. • The CAE technique simultaneously utilizes oil and protein from biomass without solvents. • The CAE technique ensured products quality and the new catalyst can be reused ten times. Edible insects are rich in oil and protein resources, and has it become increasingly important to develop them reasonably when resources are increasingly scarce. However, due to the challenges in recovering enzymes in the enzyme-assisted aqueous extraction technique and the remaining organic solvents in the extraction process based on organic solvent, it is difficult to achieve simultaneous utilization of oil and protein from edible insects. Hence, an improved enzyme-assisted aqueous extraction process based on the assistance of chitosan cross-linked Fe 3 O 4 nanoparticles (CNPs) immobilized enzymes and divalent copper ions chelation, CNPs@Cu-Trypsin-assisted aqueous extraction technique, was first proposed. The hydrolysis activity was significantly increased by 6.16 times, and the value of K cat / K m was increased by 1.7 times for the results of the formation of the hydrophilic microenvironment. Furthermore, the extraction ratio of silkworm pupae oil extracted via CNPs@Cu-Trypsin-assisted aqueous extraction technique could be increased to 93%, and the oil extraction rate could be maintained above 65% after 10 times reused. Improvement of enzyme-assisted aqueous extraction under the addition of divalent copper ions could achieve an ideal effect of oil extracted from silkworm pupae with less time. Additionally, the quality of silkworm pupae oil was significantly improved and the silkworm pupae protein hydrolysate also showed improved biological activity. Therefore, the enzyme-assisted aqueous extraction enhancement by trypsin immobilization and divalent copper ion chelation is a promising strategy for the green and sustainable exploration of edible insect oil and protein without the use of organic solvents. [ABSTRACT FROM AUTHOR]

β-1,3–1,4-Glucanase is an indispensable biocatalyst in barley brewing industry for its crucial effect in reducing the viscosity of mash. However, the unsatisfactory thermostability greatly limited its application performance. In this study, structure-based surface charge engineering was conducted aiming at thermostability improvement of BisGlu16B, a highly active β-1,3–1,4-glucanase from Bispora sp. MEY-1. By applying the enzyme thermal stability system (ETSS), residues D47, D213, and D253 were inferred to be critical sites for thermal properties. Single (D47A, D213A, and D253A) and combination (D47A/D213A/D253A) mutants were generated and compared with BisGlu16B. Among all improved mutants, D47A/D213A/D253A outstanded in thermostability. In comparison with BisGlu16B, its T 50 and T m were respectively increased by 7.0 °C and 4.3 °C, while the t 1/2 at 70 °C was 8.1 times that of the wild type. Furthermore, the catalytic activity of D47A/D213A/D253A also increased by 42.5%, compared with BisGlu16B (42,900 ± 300 U/mg vs. 30,100 ± 800 U/mg). Comparing with BisGlu16B and commercial enzyme treatment groups, under simulated malting conditions, efficiency improvement was observed in decreasement of viscosity (35.5% and 90.7%) and filtration time (30.9% and 34.6%) for D47A/D213A/D253A treatment group. Molecular dynamics simulation showed that mutation sites A47, A213, and A253 increased the protein rigidity by lowering the overall root mean square deviation (RMSD). This study may bring optimization of technology and improvement of producing efficiency to the present brewing industry. [Display omitted] • Surface charge engineering protects the catalytic core during modification. • The β-glucanase activity was improved besides the intended higher thermostability. • Reduced mash viscosity and filtration time was observed during barley malting. • The study provided a more efficient catalyst for brewing industry. [ABSTRACT FROM AUTHOR]