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The sharp increase in infections associated with multidrug-resistant (MDR) bacterial pathogens that have seriously compromised traditional chemotherapeutics is becoming a devastating public health threat worldwide. Thus, there is an urgent unmet demand to pursue alternative intervention strategies to circumvent this problem. Advances in host-acting antibacterial compounds (HACs) have provided promising, emerging approaches to reduce or eliminate internalized bacteria. In this review we focus mainly on the interactions between host cells and facultative intracellular bacteria to explore potential targets for the discovery and development of HACs. Additionally, we summarize the targets of recently described HACs and their modes of action and pharmacological activities against diverse pathogenic bacteria-associated infections. This overview of HACs sheds light on alternative strategies to treat clinical infections associated with cytosolic bacteria and the development of novel antibacterial agents. Facultative cytosolic bacterial pathogens often invade host cells to paralyze antibacterial therapies, leading to persistent and/or recurrent infections in the clinic. The spatiotemporal dynamics of cytosolic bacteria invading host cells provide systematic road maps to identify potential targets for host-acting antibacterial compounds (HACs). The elucidation of bacteria–host interactions will accelerate the discovery and development of new HACs. The broad-spectrum activities of HACs ideally serve as alternative strategies to treat unknown infections, with less selective pressures on bacteria. [ABSTRACT FROM AUTHOR]

A new method was developed for repairing Pd/Al 2 O 3 membranes with macro defects without the need of disassembling the membrane from the module. In order to target and fill the membrane defect automatically with solid particles, a TiO 2 powder was firstly tested by flowing high-pressure nitrogen as a carrier gas, followed by a heat treatment. A filter cake was found on the membrane defect but still porous. A glass powder was selected instead of TiO 2 , and the membrane defect was successfully sealed by glazing. The in-situ repair of a waste commercial Pd/Al 2 O 3 membrane separator was carried out with the glass powder, and the hydrogen flux and H 2 /N 2 selectivity of the membrane separator at 450 °C under 100 kPa reached 12.6 m3m−2h−1 and 1600, respectively. [Display omitted] • Pd/Al 2 O 3 membrane with macro defect can be repaired without membrane disassembling. • Solid particles can automatically fill and sinter on the membrane defect under nitrogen flowing. • A Li–B–Si–O glass powder can glaze and seal the membrane defect. • A waste commercial membrane separator showed high selectivity after repair. [ABSTRACT FROM AUTHOR]

Porous fin (PF) has obvious advantages in heat dissipation, so it is necessary to analyze and optimize its performance. In this paper, a multi-scale cylindrical porous fin (PF) model is built. Firstly, the fin length and height ratio are chosen as the optimization variables, constructal design is conducted with the objective of complex function (CF) composed of maximum temperature difference (MTD) and pumping power consumption (PPC). Then, an artificial neural network (ANN) model is established by using data samples, and multi-objective optimization (MOO) is performed using the NSGA-II method. The findings indicated that the optimal length and height ratio of the fin are 4.763 mm and 1.017 under the conditions that the total PF envelope volume and PF-material volume are fixed. The CF is reduced by 51.0% compared with that before optimization. The multi-scale cylindrical porous fin with different heights is superior to the single-scale one with equal height. For MOO, the lowest deviation index obtained by TOPSIS or LINMAP decision-making strategy (DMS) is 0.258. For this case, the MTD is reduced by 81.9%, and the PPC is reduced by 18.7%. Therefore, the relevant optimal structure herein can be used as the optimal design solution for the multi-scale cylindrical porous fin. • Multi-scale cylindrical porous fin heat dissipation model is built based on constructal theory. • Linear weighted sum of maximum temperature difference and power consumption is minimized. • Multi-objective optimization based on artificial neural network and NSGA-II is also conducted. • Optimal structure of for multiple requirements is gained by three decision-making strategies. • Hot point temperature and pumping power consumption are reduced by 81.9% and 18.7%. [ABSTRACT FROM AUTHOR]

Garnet type solid-state electrolytes (SSEs) possess high stability against Li metal, intrinsic safety, and wide electrochemical window. To achieve the all-solid-state batteries (ASSBs) with high gravimetric/volumetric energy density and high power density, flat thin garnet SSEs with a high ionic conductivity of > 10−4 S/cm are required. However, the current fabrication processes are challengeable to maintain both the high ionic conductivity and the flat skeleton due to the severe Li loss during processing and the fragile nature of thin films. Herein, we introduce a rapid Li compensation (RLC) technique that combines the ultra-fast high-temperature sintering (UHS) technique with the tape casting process to produce highly ionic conductive, flat garnet SSE thin films. The freestanding Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) thin film with a thickness of 40 µm, fabricated using this technique, displays a surface roughness of 5 µm and a relative density of 95%. After a 10-seconds Li compensation, the compensated LLZTO film displays an ionic conductivity of 4.3 × 10−4 S/cm, 2 times higher than the non-compensated one. As a proof of concept, this RLC technique proposes a new strategy for the fabrication of high-performance ceramic thin films and also lays a solid foundation for the application of ASSBs. [Display omitted] • A novel rapid Li compensation technique for garnet-type SSE thin films is introduced for high-performance all-solid-state batteries (ASSBs). • The compensated Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) thin film displayed a 2 times increase in ionic conductivity, showing promise for future high-energy and high-power-density ASSBs. [ABSTRACT FROM AUTHOR]

Summary In addition to acting as building blocks for biosynthesis, amino acids might serve as signaling regulators in various physiological and pathological processes. However, it remains unknown whether amino acid levels affect the activities of hematopoietic stem cells (HSCs). By using a genetically encoded fluorescent sensor of the intracellular levels of branched-chain amino acids (BCAAs), we could monitor the dynamics of BCAA metabolism in HSCs. A mitochondrial-targeted 2C-type Ser/Thr protein phosphatase (PPM1K) promotes the catabolism of BCAAs to maintain MEIS1 and p21 levels by decreasing the ubiquitination-mediated degradation controlled by the E3 ubiquitin ligase CDC20. PPM1K deficiency led to a notable decrease in MEIS1/p21 signaling to reduce the glycolysis and quiescence of HSCs, followed by a severe impairment in repopulation activities. Moreover, the deletion of Ppm1k dramatically extended survival in a murine leukemia model. These findings will enhance the current understanding of nutrient signaling in metabolism and function of stem cells. [ABSTRACT FROM AUTHOR]

A certain level of disagreement between the chemical analysis of androstenone and skatole and the human perception of boar taint has been found in many studies. Here we analyze whether the fatty acid composition can explain such inconsistency between sensory evaluation and chemical analysis of boar taint compounds. Therefore, back fat samples ( n = 143) were selected according to their sensory evaluation by a 10-person sensory panel, and the chemical analysis (stable isotope dilution analysis with headspace solid-phase microextraction and gas chromatography–mass spectrometry) of androstenone and skatole. Subsequently a quantification of fatty acids using gas chromatography-flame ionization detection was conducted. The correlation analyses revealed that several fatty acids are significantly correlated with androstenone, skatole, and the sensory rating. However, multivariate analyses (principal component analysis) revealed no explanation of the fatty acid composition with respect to the (dis-)agreement between sensory and chemical analysis. [ABSTRACT FROM AUTHOR]

The feasibility of Raman spectroscopy for boar taint detection and classification was investigated using tainted and untainted backfat samples of 46 boars. For this exploratory study, backfat samples were selected according to their levels of androstenone and skatole as determined by gas chromatography and their sensory score by a trained panel. Raman spectra were collected with a portable device at freshly cut surfaces of frozen–thawed samples. Both inner and outer layers of subcutaneous fat were studied. Their varying level of unsaturation was reflected in the Raman spectra. Partial least squares regression discriminant analysis (PLS-DA) was applied to the spectra together with various pre-processing methods. A model using only spectra obtained at the inner layer resulted in the highest classification accuracy for boar taint (81% of samples correctly classified). The discrimination is shown to reflect differences in the degree of fatty acid saturation between tainted and untainted boars. In conclusion, the findings suggest that with further development Raman spectroscopy may be used to classify boar taint. [ABSTRACT FROM AUTHOR]

Spatiotemporal dynamic information on surface water area and level is a prerequisite for effective wetland conservation and management. However, such information is either unavailable or difficult to obtain. In this study, for the first time, we leverage Landsat imagery, ICESat-2 and airborne LiDAR data to develop time series of water body dynamics over the last 35 years (1987–2021) using machine learning method on a cloud computing platform for lakes identified as international importance in the Western District Lakes Ramsar site in Victoria, Australia. Our results reveal distinct seasonal (dry and wet) variation patterns and long-term changes in trends of lake water areas and levels in response to seasonal rainfall variations and regional climate changes for the periods of before, during and after the Millennium Drought when southeast Australia experienced unprecedented dry conditions. Lake water bodies have not recovered to the status of pre-Millennium Drought, and many permanent Ramsar-listed lakes in the region have become to ephemeral lakes due to climate change. The outcome of this study provides a baseline to help understand the historical and ongoing status of the Ramsar-listed lakes in a warming and drying climate in support of the development of strategic plan to implement international obligations for wetlands protection under the Ramsar Convention. • Leverage Landsat, ICESat-2 and LiDAR data for time series of lake water variations. • For the first time, long-term lake water dynamics on a Ramsar site were developed. • Distinct variation patterns of water bodies caused by climate change were observed. • Most of the Ramsar-listed lakes are no longer permanent, but now ephemeral. • Lake water bodies have not recovered back to the status of pre-Millennium Drought. [ABSTRACT FROM AUTHOR]

Thermoelectric (TE) materials can interconvert waste heat into electricity, thus are promising for power generation and solid-state refrigeration. The thermoelectric properties of a certain material strongly correlate with its chemical, structural and electronic features; therefore, a thorough characterization of these features is not only crucial to profoundly understand the material itself, but also helps to design new materials with desired properties. Under this circumstance, various electron microscopy (EM) techniques are developed, from micro-scale to atomic-scale, two-dimensional (2-D) to 3-D, and static to dynamic. In this review, we review advanced EM techniques already applied in and also look into the perspective of introducing more EM techniques into the field of thermoelectrics. Specifically, we firstly summarize “what have been done” involving: structural and chemical characterizations of all-scale “imperfectness”, electronic structure investigation, 3-D morphology and dynamic evolution of nanostructures, and atomic-scale mapping of Seebeck coefficient and defects; based on these characterized features, we then briefly review the calculations on electrical and thermal transport properties to illustrate the structure–property correlations. In what follows, we propose “what can be done” in TEs via EM techniques including: valence-electron distribution, quantitative measurement of atomic displacement, point defect characterization, local band gap measurement, phonon excitation detection, electrostatic potential determination, thermal stability of nanostructures, and in-situ observation and measurement of local TE effects. [ABSTRACT FROM AUTHOR]

Pathogenic bacteria evolve multiple strategies to hijack host cells for intracellular survival and persistent infections. Previous studies have revealed the intricate interactions between bacteria and host cells at genetic, biochemical and even single molecular levels. Mechanical interactions and mechanotransduction exert a crucial impact on the behaviors and functions of pathogenic bacteria and host cells, owing to the ubiquitous mechanical microenvironments like extracellular matrix (ECM) stiffness. Nevertheless, it remains unclear whether and how ECM stiffness modulates bacterial infections and the sequential outcome of antibacterial therapy. Here we show that bacteria tend to adhere to and invade epithelial cells located on the regions with relatively high traction forces. ECM stiffness regulates spatial distributions of bacteria during the invasion through arrangements of F-actin cytoskeletons in host cells. Depolymerization of cytoskeletons in the host cells induced by bacterial infection decreases intracellular accumulation of antibiotics, thus preventing the eradication of invaded bacterial pathogens. These findings not only reveal the key regulatory role of ECM stiffness, but suggest that the coordination of cytoskeletons may provide alternative approaches to improve antibiotic therapy against multidrug resistant bacteria in clinic. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene-based structures have attracted much attention due to their unique physicochemical properties and potential applications in various fields. In this work, we develop a facile strategy for growing Co and Zn-contained nitrogen-doped carbon nanotubes on the graphene sheets for the absorption of electromagnetic wave (EMW). The as-fabricated 3D structures with a larger surface area have high electrical conductivities, abundant defects, numerous interfaces and porous feature, endowing them to excellent EMW absorption performance. The minimal reflection loss and efficient absorption bandwidth of the optimized 3D structure can reach to −47.31 dB and 4.01 GHz at a low thickness of merely 1.5 mm, respectively. Even at the thickness of 1.2–1.5 mm, the minimal reflection losses are less than −10 dB. Furthermore, the filler mass loading of the 3D structures is only 6 wt%, lower than those of most of the reported absorbers. Our results highlight the importance of 3D structures composed of graphene and nitrogen-doped carbon nanotubes to high-efficiency EMW absorption. Image 1 [ABSTRACT FROM AUTHOR]

High moisture herbaceous residues (HR) cause a series of environment problems. Torrefaction has proven to be a promising technology for upgrading the fuel properties of biomass. In this study, a typical HR, Licorice residue (LR), was torrefied in a tubular reactor under nitrogen at 210, 240 and 280 °C. The effect of temperature on the fuel properties and the decomposition characteristic of the torrefied samples, as well as the pyrolysis products, were investigated. The mass and energy yield were altered in the range of 91.8–52.3% and 99.3–72.9%, respectively. The higher heating value (HHV) value of the torrefied sample increased by 8.1–39.5% from light to severe torrefaction, compared to untorrefied LR, and reached up to 23.3 MJ/kg at 280 °C. Torrefaction decreased the content of oxygenated organic compounds and the acidity of bio-oil from pyrolysis. The increase in alkanes from torrefied sample pyrolysis implies that torrefied LR has the potential for use in liquid fuel production. The present findings revealed that torrefaction turns industrial LR with poor energy content into a more easily exploitable solid fuel. [ABSTRACT FROM AUTHOR]

Constructal theory is used to build a hybrid heat-sink model with rectangular microchannel and porous fin in a 3D electronic device. Firstly, constructal design is conducted with objective of minimizing linear weighted sum of maximum temperature-difference and pump power consumption with fixed total volumes of 3D electronic device, porous fin and microchannel. The optimal microchannel aspect ratio and elemental number are gained. Secondly, multi-objective-optimization is conducted based on NSGA-II, which uses the "gamultiobj" function of Matlab's artificial neural-network toolbox. The findings indicate that when microchannel aspect ratio and elemental number are 0.29 and 38, respectively, complex function achieves its double minimum of 0.810, which is decreased by 19.0% compared to its original value. Therefore, optimizing microchannel aspect ratio and elemental number simultaneously contributes to improving the comprehensive performance of 3D electronic device. Based on LINMAP, TOPSIS and Shannon Entropy decision-making strategies, the multi-objective solution set is compared. The third decision-making method has the smallest deviation index. The corresponding optimal microchannel aspect ratio and elemental number are 0.35 and 32, respectively, which can be used as the optional structure design scheme. The research findings can serve as a new theoretical reference for designing hybrid cooling system in a 3D electronic device. • Hybrid heat-sink model with rectangular microchannel and porous fin in a 3D electronic device. • Constructal designs with fixed total volumes of 3D electronic device, porous fin and microchannel. • It is to minimize maximum temperature-difference and pump power consumption objectives. • The first is to minimize linear weighted sum of two optimization objectives. • Then to minimize two objectives with ANN, NSGA-II and three decision-making methods. [ABSTRACT FROM AUTHOR]

• Herbal medicine waste was torrefied under different conditions. • Temperature shows a greater effect on the torrefaction process than the agents. • The HMW samples torrefied under different conditions are easy to ignite. • The combustion properties of the HMW were enhanced significantly after torrefaction. • The torrefied HMW has the potential for solid fuel production. To explore the feasibility of using herbal medicine waste (HMW) as solid fuel, HMW was torrefied under different temperatures and atmospheres. The physicochemical properties and combustion behaviors of the torrefied HMW were investigated. Temperature was found to be the most influential factor affecting the torrefaction. Torrefaction improved the hydrophobicity of HMW and decreased the equilibrated moisture uptake from 24.48(0.083) % to 15.22(0.054) %. The HMW samples torrefied under different conditions are easy to ignite. The comprehensive combustibility index (S) of the torrefied HMW increased by 3–5 folds compared to that of the raw sample. In general, the HMW torrefied under lower temperatures and under CO 2 and O 2 have better flammability. The present results revealed that the torrefied HMW exhibited good combustion characteristics and can thus be used for solid fuel production, such as fuels for co-combustion or raw materials for pelletization. [ABSTRACT FROM AUTHOR]

The combination of torrefaction pretreatment and catalytic pyrolysis of herbaceous medicine waste (HMW) was performed. The effects of torrefaction, pyrolysis temperature, SiO 2 /Al 2 O 3 atomic ratio (SAR) and catalyst-to-feedstock (C/F) ratio on the distribution of aromatic hydrocarbons (AHs) was investigated. The formation of coke and its effects on the catalytic performance of the catalyst were evaluated. The results demonstrated that zeolite can effectively convert the torrefied HMW into AHs. The liquid products were dominated by monocyclic aromatic hydrocarbons (MAHs), in which toluene and xylene were formed preferentially over other aromatics. The total content of benzene, toluene, ethylbenzene, p-xylene, and naphthalene (BTEXN) reached 49.23–76.31%. Temperature, SAR and C/F ratio exhibit a greater influence on AHs formation than the torrefaction agents. A higher pyrolysis temperature and C/F ratio can inhibit coke formation, while higher SAR is beneficial to coke formation. The catalyst with a lower SAR yield more AHs and less coke. Coke was initially formed on the surface of the catalyst at low temperature, but it was more likely to form in the pores of the catalyst at high temperatures. The results show that the combination of torrefaction and catalytic pyrolysis is a potential approach for converting HMW into valuable bio-oils. [Display omitted] • Torrefaction and catalytic pyrolysis of herbaceous medicine waste was performed. • Zeolite can effectively convert the torrefied HMW into aromatic hydrocarbons. • Lower pyrolysis temperature and SAR of catalyst was beneficial to BTEXN formation. • Coke deposition during pyrolysis decreases the activity of zeolite catalyst. • Oxygenated compounds were the coke precursors during catalytic pyrolysis. [ABSTRACT FROM AUTHOR]

• Catalytic fast pyrolysis of herbal medicine wastes was performed. • ZSM-5 effectively converts oxygenates into aromatic hydrocarbons. • Temperature and acidity of zeolite exert great influence on BTEXN formation. • The maximum content of BTEXN was 73.45 % at 500 °C and 72.21 % at lower SARs. • The oxygenates and aliphatic hydrocarbons was the precursors of coke during CFP. Catalytic pyrolysis is an effective method to upgrade biomass pyrolytic bio-oil. In this study, catalytic fast pyrolysis (CFP) of licorice residue (LR) over ZSM-5 was conducted using pyrolysis–gas chromatography/mass spectrometry. The effects of temperature, Si/Al atomic ratio (SAR) and catalyst to feedstock (C/F) ratio on the formation of aromatic hydrocarbons (AHs) were investigated. The results indicated that ZSM-5 effectively converts oxygenates into AHs. Specifically, benzene, toluene, ethylbenzene, p-xylene and naphthalene (BTEXN) were the dominant components. The pyrolysis temperature and acidity of zeolite exert a greater influence on the formation of BTEXN. The maximum content of BTEXN was 73.45 % at 500 °C and 72.21 % at lower SARs (27 and 36). Coke can be formed and deposited on the zeolite during CFP of LR, which cause the deactivation of catalyst. A higher pyrolysis temperature and C/F ratios inhibits the coke formation, while a higher SAR is beneficial to coke formation. The large oxygenated molecules and aliphatic hydrocarbons (AHCs) was the precursors of coke during catalytic pyrolysis. The coke was tended to disperse on the surface of catalyst at low temperature. However, it was largely deposited in the channels of zeolite catalyst at high temperatures. This study reveals that ZSM-5 is an effective catalyst for the utilization of herbal medicine wastes. The pyrolytic bio-oil has high potential for use in fuels or renewable chemical production. [ABSTRACT FROM AUTHOR]