Revealing Prdx4 as a potential diagnostic and therapeutic target for acute pancreatitis based on machine learning analysis.

Acute pancreatitis (AP) is a common systemic inflammatory disease resulting from the activation of trypsinogen by various incentives in ICU. The annual incidence rate is approximately 30 out of 100,000. Some patients may progress to severe acute pancreatitis, with a mortality rate of up to 40%. Therefore, the goal of this article is to explore the key genes for effective diagnosis and treatment of AP. The analysis data for this study were merged from two GEO datasets. 1357 DEGs were used for functional enrichment and cMAP analysis, aiming to reveal the pathogenic genes and potential mechanisms of AP, as well as potential drugs for treating AP. Importantly, the study used LASSO and SVM-RFE machine learning to screen the most likely AP occurrence biomarker for Prdx4 among numerous candidate genes. A receiver operating characteristic of Prdx4 was used to estimate the incidence of AP. The ssGSEA algorithm was employed to investigate immune cell infiltration in AP. The biomarker Prdx4 gene exhibited significant associations with a majority of immune cells and was identified as being expressed in NKT cells, macrophages, granulocytes, and B cells based on single-cell transcriptome data. Finally, we found an increase in Prdx4 expression in the pancreatic tissue of AP mice through immunohistochemistry. After treatment with recombinant Prdx4, the pathological damage to the pancreatic tissue of AP mice was relieved. In conclusion, our study identified Prdx4 as a potential AP hub gene, providing a new target for treatment.

Hypoxia-induced TRPM7 promotes glycolytic metabolism and progression in hepatocellular carcinoma.

BACKGROUND: Hypoxia disrupts glucose metabolism in hepatocellular carcinoma (HCC). Transient receptor potential cation channel, subfamily M, member 7 (TRPM7) plays an ontogenetic role. Thus, we aimed to explore the regulation of TRPM7 by hypoxia-induced factor (HIF) and its underlying mechanisms in HCC. METHODS: hypoxia was induced in multiple HCC cells using 1% O2 or CoCl2 treatment, and subsequently blocked using siRNAs targeting HIF-1α or HIF-2α as well as a HIF-1α protein synthesis inhibitor. The levels of HIF-1α and TRPM7 were assessed using quantitative PCR (qPCR) and Western blot analysis. Chromatin immunoprecipitation (ChIP) and luciferase assays were performed to observe the regulation of TRPM7 promoter regions by HIF-1α. A PCR array was utilized to screen glucose metabolism-related enzymes in HEK293 cells overexpressing TRPM7 induced by tetracycline, and then verified in TRPM7-overexpressed huh7 cells. Finally, CCK-8, transwell, scratch and tumor formation experiments in nude mice were conducted to examine the effect of TRPM7 on proliferation and metastasis in HCC. RESULTS: Exposure to hypoxia led to increase the levels of TRPM7 and HIF-1α in HCC cells, which were inhibited by HIF-1α siRNA or enhanced by HIF-1α overexpression. HIF-1α directly bound to two hypoxia response elements (HREs) in the TRPM7 promoter. Several glycolytic metabolism-related enzymes, were simultaneously upregulated in HEK293 and huh7 cells overexpressing TRPM7 during hypoxia. In vitro and in vivo experiments demonstrated that TRPM7 promoted the proliferation and metastasis of HCC cells. CONCLUSIONS: TRPM7 was directly transcriptionally regulated by HIF-1α, leading to glycolytic metabolic reprogramming and the promotion of HCC proliferation and metastasis in vitro and in vivo. Our findings suggest that TRPM7 might be a potential diagnostic indicator and therapeutic target for HCC.

[The experience on the construction of the cluster prevention and control system for COVID-19 infection in designated hospitals during the period of "Category B infectious disease treated as Category A"].

The COVID-19 epidemic has spread to the whole world for three years and has had a serious impact on human life, health and economic activities. China's epidemic prevention and control has gone through the following stages: emergency unconventional stage, emergency normalization stage, and the transitional stage from the emergency normalization to the "Category B infectious disease treated as Category B" normalization, and achieved a major and decisive victory. The designated hospitals for prevention and control of COVID-19 epidemic in Tianjin has successfully completed its tasks in all stages of epidemic prevention and control, and has accumulated valuable experience. This article summarizes the experience of constructing a hospital infection prevention and control system during the "Category B infectious disease treated as Category A" period in designated hospital. The experience is summarized as the "Cluster" hospital infection prevention and control system, namely "three rings" outside, middle and inside, "three districts" of green, orange and red, "three things" before, during and after the event, "two-day pre-purification" and "two-director system", and "one zone" management. In emergency situations, we adopt a simplified version of the cluster hospital infection prevention and control system. In emergency situations, a simplified version of the "Cluster" hospital infection prevention and control system can be adopted. This system has the following characteristics: firstly, the system emphasizes the characteristics of "cluster" and the overall management of key measures to avoid any shortcomings. The second, it emphasizes the transformation of infection control concepts to maximize the safety of medical services through infection control. The third, it emphasizes the optimization of the process. The prevention and control measures should be comprehensive and focused, while also preventing excessive use. The measures emphasize the use of the least resources to achieve the best infection control effect. The fourth, it emphasizes the quality control work of infection control, pays attention to the importance of the process, and advocates the concept of "system slimming, process fattening". Fifthly, it emphasizes that the future development depends on artificial intelligence, in order to improve the quality and efficiency of prevention and control to the greatest extent. Sixth, hospitals need to strengthen continuous training and retraining. We utilize diverse training methods, including artificial intelligence, to ensure that infection control policies and procedures are simple. We have established an evaluation and feedback mechanism to ensure that medical personnel are in an emergency state at all times.

Outstanding nonlinear optical properties of all-inorganic perovskite CsPbX3 (X=Cl, Br, I) precursor solutions and polycrystalline films.

In this work, we systematically explore the third-order nonlinear optical properties of all-inorganic CsPbX3 (X = Cl, Br, I) perovskite precursor solutions and thin films using femtosecond and nanosecond laser pulses. We show that these samples possess strong two-photon absorption (TPA) and reverse saturable absorption (RSA), which depend on the excitation wavelength. The obtained nonlinear absorption and refraction coefficients for precursor solutions are followed by the relation CsPbCl3 > CsPbBr3 > CsPbI3 for the 800 and 1,064 nm excitation wavelengths, whereas this relation became reverse in the case of 355 and 400 nm laser pulses. It was shown that CsPbCl3 thin film possesses RSA at 400 nm, CsPbCI3 shows RSA+ saturable absorption (SA), and CsPbBr3 demonstrates SA + RSA. In addition, at 800 nm excitation, the CsPbBr3 thin films show SA + RSA at low peak intensity, and the absorption becomes reverse (TPA+SA) with a further increase in the input laser intensity. The suitability of nonlinear absorption depends on the band gap of the thin films with respect to the pumping photon energy. Our studies demonstrate that these perovskites can be used as the excellent materials for the all-optical signal processing.

A SARS-CoV-2 nanoparticle vaccine based on chemical conjugation of loxoribine and SpyCatcher/SpyTag.

SARS-CoV-2 is a particularly transmissible virus that renders the worldwide COVID-19 pandemic and global severe respiratory distress syndrome. Protein-based vaccines hold great advantages to build the herd immunity for their specificity, effectiveness, and safety. Receptor-binding domain (RBD) of SARS-CoV-2 is an appealing antigen for vaccine development. However, adjuvants and delivery system are necessitated to enhance the immunogenicity of RBD. In the present study, RBD was chemically conjugated with loxoribine and SpyCatcher/SpyTag, followed by assembly to form a nanoparticle vaccine. Loxoribine (a TLR7/8 agonist) acted as an adjuvant, and nanoparticles functioned as delivery system for the antigen and the adjuvant. The nanoparticle vaccine elicited high RBD-specific antibody titers, high neutralizing antibody titer, and strong ACE2-blocking activity. It stimulated high splenic levels of Th1-type cytokines (IFN-γ and IL-2) and Th2-type cytokines (IL-4 and IL-5) in BALB/c mice. It promoted the splenocyte proliferation, enhanced the CD4+ and CD8+ T cell percentage and stimulated the maturation of dendritic cells. The vaccine did not render apparent toxicity to the organs of mice. Thus, the nanoparticle vaccine was of potential to act as a preliminarily safe and effective candidate against SARS-CoV-2.

Determination of the Dissipation Dynamics and Terminal Residue of Bupirimate and Its Metabolites in Cucumber by QuEChERS-Based UPLC-MS/MS.

Bupirimate is widely used as a highly active systemic fungicide. However, the frequent and heavy use of bupirimate has led to pesticide residues in crops that threaten human health and food safety. At present, there is limited research on the detection of ethirimol, which is the metabolite of bupirimate. This study established an ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to simultaneously detect bupirimate and ethirimol residues based on QuEChERS pretreatment. The average recoveries of bupirimate and ethirimol in cucumber were between 95.2 and 98.7%, respectively, with relative standard deviations (RSDs) of 0.92-5.54% at fortified levels of 0.01, 0.1, and 5 mg L-1. The established method was used to determine the residues in field trials in 12 regions of China, and the final residues of bupirimate were all less than the maximum residue limit (MRL). Since the risk quotient (RQ) of bupirimate and ethirimol in cucumber was less than 1.3%, the dietary risk assessment indicated that bupirimate and ethirimol had a low long-term dietary risk to the general population in China. This study provides effective guidance on the proper use of bupirimate in cucumber fields and a reference for establishing the MRL of bupirimate in China.

Neuroprotective Strategies for Stroke by Natural Products: Advances and Perspectives.

Cerebral ischemic stroke is a disease with high prevalence and incidence. Its management focuses on rapid reperfusion with intravenous thrombolysis and endovascular thrombectomy. Both therapeutic strategies reduce disability, but the therapy time window is short, and the risk of bleeding is high. Natural products (NPs) have played a key role in drug discovery, especially for cancer and infectious diseases. However, they have made little progress in clinical translation and pose challenges to the treatment of stroke. Recently, with the investigation of precise mechanisms in cerebral ischemic stroke and the technological development of NP-based drug discovery, NPs are addressing these challenges and opening up new opportunities in cerebral stroke. Thus, in this review, we first summarize the structure and function of diverse NPs, including flavonoids, phenols, terpenes, lactones, quinones, alkaloids, and glycosides. Then we propose the comprehensive neuroprotective mechanism of NPs in cerebral ischemic stroke, which involves complex cascade processes of oxidative stress, mitochondrial damage, apoptosis or ferroptosis-related cell death, inflammatory response, and disruption of the blood-brain barrier (BBB). Overall, we stress the neuroprotective effect of NPs and their mechanism on cerebral ischemic stroke for a better understanding of the advances and perspective in NPs application that may provide a rationale for the development of innovative therapeutic regimens in ischemic stroke.

Mucosal SARS-CoV-2 Nanoparticle Vaccine Based on Mucosal Adjuvants and Its Immune Effectiveness by Intranasal Administration.

SARS-CoV-2 is a respiratory virus that causes significant threats to human health. Mucosal immunity provides a first-line defense to prevent the infection of SARS-CoV-2 in the respiratory tract. Because most SARS-CoV-2 vaccines could not stimulate mucosal immunity in the respiratory tract, appropriate mucosal adjuvants or delivery systems are needed for mucosal vaccine development. Mannan, polyarginine, and 2',3'-cGAMP are three mucosal adjuvants that could stimulate mucosal immunity. In the present study, the three adjuvants were assembled with a receptor-binding domain (RBD) by electrostatic interaction to generate a nanoparticle vaccine (RBD-MP-cG). RBD-MP-cG elicited mucosal IgA and IgG response in bronchoalveolar lavage and nasal lavage by intranasal administration. It induced a robust RBD-specific antibody response, high levels of protective neutralizing antibody, and ACE2-blocking activity in the mouse sera. It stimulated the splenic secretion of high levels of Th1-, Th2-, and Th17-type cytokines. Thus, RBD-MP-cG elicited strong mucosal immunity and systematic immunity by intranasal administration. RBD-MP-cG was expected to act as a safe, effective, and easily produced mucosal nanoparticle vaccine to combat the infection of SARS-CoV-2.

Controlling basal plane sulfur vacancy in water splitting MoSx/NiF electrocatalysts through electric-field-assisted pulsed laser ablation.

Eco-friendly, efficient, and durable electrocatalysts from earth-abundant materials are crucial for water splitting through hydrogen and oxygen generation. However, available methods to fabricate electrocatalysts are either hazardous and time-consuming or require expensive equipment, hindering the large-scale, eco-friendly production of artificial fuels. Here, we present a rapid, single-step method for producing MoSx/NiF electrocatalysts with controlled sulfur-vacancies via electric-field-assisted pulsed laser ablation (EF-PLA) in liquid and in-situ deposition on nickel foam, enabling efficient water splitting. Electric-field parameters efficiently control S-vacancy active sites in electrocatalysts. Higher electric fields yield a MoSx/NiF electrocatalyst with a larger density of S-vacancy sites, suited for HER due to lower Gibbs free energy for H∗ adsorption, while lower electric fields produce an electrocatalyst with lower S-vacancy sites, better suited for OER, as shown by both experimental and theoretical results. The present work opens a horizon in designing high-efficiency catalysts, for a wide range of chemical reactions.

Hydroxyethyl Starch-Bovine Hemoglobin Conjugate as an Effective Oxygen Carrier with the Ability to Expand Plasma.

Hemorrhagic shock leads to intravasal volume deficiency, tissue hypoxia, and cellular anaerobic metabolism. Hemoglobin (Hb) could deliver oxygen for hypoxic tissues but is unable to expand plasma. Hydroxyethyl starch (HES) could compensate for the intravasal volume deficiency but cannot deliver oxygen. Thus, bovine Hb (bHb) was conjugated with HES (130 kDa and 200 kDa) to develop an oxygen carrier with the ability to expand plasma. Conjugation with HES increased the hydrodynamic volume, colloidal osmotic pressure, and viscosity of bHb. It slightly perturbed the quaternary structure and heme environment of bHb. The partial oxygen pressures at 50% saturation (P 50) of the two conjugates (bHb-HES130 and bHb-HES200) were 15.1 and 13.9 mmHg, respectively. The two conjugates showed no apparent side effects on the morphology and rigidity, hemolysis, and platelet aggregation of red blood cells of Wistar rats. Thus, bHb-HES130 and bHb-HES200 were expected to function as an effective oxygen carrier with the ability to expand plasma.

TCS01 Two-Component System Influenced the Virulence of Streptococcus pneumoniae by Regulating PcpA.

Streptococcus pneumoniae relies on two-component systems (TCSs) to regulate the processes of pathogenicity, osmotic pressure, chemotaxis, and energy metabolism. The TCS01 system of S. pneumoniae is composed of HK01 (histidine kinase) and RR01 (response regulator). Previous studies have reported that an rr01 mutant reduced the pneumococcal virulence in rat pneumonia, bacteremia, a nasopharyngeal model, and infective endocarditis. However, the mechanism of TCS01 (HK/RR01) regulating pneumococcal virulence remains unclear. Here, pneumococcal mutant strains Δrr01, Δhk01, and Δrr01&hk01 were constructed, and bacterial adhesion and invasion to A549 cells were compared. RNA sequencing was performed in D39 wild-type and Δrr01 strains, and transcript profile changes were analyzed. Differentially expressed virulence genes in the Δrr01 strain were screened out and identified by quantitative real-time PCR (qRT-PCR). Our results showed that pneumococcal mutant strains exhibited attenuated adhesion and invasion to A549 cells and differential transcript profiles. Results of qRT-PCR identification showed that the differential virulence genes screened out were downregulated. Among those changed virulence genes in the Δrr01 strain, the downregulated expression level of choline binding protein pcpA was the most obvious. Complementation of rr01 and overexpression of pcpA in the Δrr01 strain partially restored both pneumococcal adhesion and invasion, and rr01 complementation made the expression of pcpA upregulated. These findings revealed that rr01 influenced pneumococcal virulence by regulating pcpA.

Go beyond the limit: Rationally designed mixed-dimensional perovskite/semiconductor heterostructures and their applications.

Halide perovskite heterojunctions rationally integrate the chemical and physical properties of multi-dimensional perovskites and judiciously chosen semiconductor materials, offering the promise of going beyond the limit of a single component. This emerging platform of materials innovation offers fresh opportunities to tune material properties, discover interesting phenomena, and enable novel applications. In this review, we first discuss the fundamentals of forming heterojunctions with perovskites and a wide range of semiconductors, and then we give an overview of the research progress of halide perovskite heterojunctions in terms of their optical, electrical, and mechanical properties, focusing on how the heterojunction tunes the energy band structure, electrical transport, and charge recombination behaviors. We further outline the progress of perovskite-based heterojunctions in optoelectronics. Finally, the challenges and future research directions for perovskite/semiconductor heterojunctions are discussed.

Measurement of Optical Properties of CH3NH3PbX3 (X = Br, I) Single Crystals Using Terahertz Time-Domain Spectroscopy.

Organometallic lead bromide and iodide perovskite single crystals (PSCs) are potential candidates for terahertz applications. Herein, we performed terahertz time-domain spectroscopy (THz-TDS) in the frequency range of 0.1-3.0 THz on different thicknesses of MAPbBr3 (0.3, 0.6, and 0.8 mm) and MAPbI3 (0.6, 0.8, 0.9, 1.3, and 2.3 mm). The measurements were carried out with respect to the position (along the focal area), azimuthal rotation of the PSCs, and incidence angles of the reference THz pulse on the PSCs' surface. Based on the transmitted THz pulses from PSCs from the above measurements, we calculated the real and imaginary parts of the refractive index, dielectric constants, absorption coefficients, and dark conductivity. These optical parameters tend to increase with decreases in the PSCs' thicknesses. The transmission spectra of the terahertz electric field indicate that the measured optical properties do not vary significantly with the position and orientation of PSCs. The real parts of the refractive index and dielectric constants are higher than the imaginary values for both PSCs. On the other hand, a slight blueshift in the optical phonon vibrations corresponding to Pb-Br/I-Pb and Pb-Br/I bonds is observed with an increase in thickness. Interestingly, the phonon vibrations do not vary with the incidence angle of the THz pulses on the same crystal's surface. The optical parameters based on THz-TDS reveal that the PSCs satisfy the requirement for tunable THz devices which need suitable, sensitive, and stable absorption properties between 0.1 and 3 THz.

A Nomogram Model for Mortality Risk Prediction in Pulmonary Tuberculosis Patients Subjected to Directly Observed Treatment Shortcourse (DOTS).

We analyzed the risk factors of mortality for patients with pulmonary tuberculosis under the Directly Observed Treatment Shortcourse (DOTS) and established a predictive nomogram for the risk of mortality. The retrospective cohort analysis was conducted on the treatment outcomes of 11207 tuberculosis patients in the tuberculosis management information system in Tianjin from 2014 to 2019. Based on the multivariable unconditional logistic regression, we analyzed the risk factors of mortality in patients with pulmonary TB and established the death risk prediction nomogram. We further applied cross-validation and the receiver operating characteristic (ROC) curve to explore the efficiency of the nomogram. There were 10,697 patients in the survival group and 510 in the mortality group who had successfully initiated DOTS, and the mortality rate was 4.55%. Multivariable logistic regression analysis showed that age, male, relapse cases, first sputum positivity, patient delay, and HIV-positive were independent risk factors for pulmonary TB death. The calibration curve shows that the average absolute error between the predicted mortality risk and the actual death risk is 0.003. The ROC curve shows that the area under the curve where the line-up model predicts the risk of death is 0.816 (95% CI: 0.799∼0.832). The nomogram model based on independent risk factors of mortality in TB patients shows good discrimination and accuracy, with potentially high clinical value in screening patients with a high risk of death, which could be useful for setting the interventional strategies in patients with tuberculosis who had successfully initiated DOTS.

Harmonics Generation in the Laser-Induced Plasmas of Metal and Semiconductor Carbide Nanoparticles.

Carbon-containing plasma is an attractive medium for generation of harmonics of laser pulses in the extreme ultraviolet range. We ablate two metal carbide (B4C and Cr3C2) nanoparticles and silicon carbide (SiC) nanoparticles and generate harmonics after propagation of 35 fs pulses through the laser-induced plasmas. We analyze the spectra, spectral shifts, and splitting of harmonics from nanoparticles-contained plasmas, which demonstrate the chirp-related harmonic cut-off scaling. In addition, we present the simplified two-color pump model calculations of HHG based on the strong field approximation.

Ultrahigh-efficient BiOBr-x%La@y%CNQDs nanocomposites with enhanced generation and separation of photogenerated carriers towards bisphenol A degradation and toxicity reduction.

In this study, a series of hierarchical flower-like La-doped BiOBr composites modified with carbon nitride quantum dots (BiOBr-x%La@y%CNQDs) was synthesized using a microwave solvothermal method in combination with a calcination method. It was found that La doping and CNQDs co-decorated with BiOBr showed much better photoreactivity for bisphenol A (BPA) degradation than pure BiOBr. The best degradation and mineralization efficiencies of BPA were 100% and 77% within 12 min at La and CNQDs contents of 1% and 1.25%, respectively. Various characterization results demonstrated that this synergistic effect on BiOBr-1%La@1.25%CNQDs was attributed to its improved light-harvesting properties, enhanced photogenerated electron and holes pairs separation and interfacial charge transfer. Degradation pathways were proposed based on active species analysis, identification of nine intermediates, and density functional theory (DFT) calculations. Furthermore, a bioluminescence assay of the inhibition rate of the luminescent bacterium Vibrio qinghaiensis sp. Q67 showed that BiOBr-1%La@1.25%CNQDs have superior detoxification ability. The present study provides some insight into the design of ultrahigh-efficiency nanojunction photocatalysts with a broadened photoabsorption range and improved separation efficiency of photogenerated carriers to enhance the degradation and detoxification performance of BPA.

A SARS-CoV-2 vaccine based on conjugation of SARS-CoV-2 RBD with IC28 peptide and mannan.

SARS-CoV-2 is a particularly transmissible virus that causes a severe respiratory disease known as COVID-19. Safe and effective vaccines are urgently needed to combat the COVID-19 pandemic. The receptor-binding domain (RBD) of SARS-CoV-2 spike protein elicits most neutralizing antibodies during viral infection and is an ideal antigen for vaccine development. In particular, RBD expressed by E. coli is amenable to low cost and high-yield manufacturability. The adjuvant is necessitated to improve the immunogenicity of RBD. IC28, a TLR5-dependent adjuvant, is a peptide from bacterial flagellin. Mannan is a ligand of TLR-4 or TLR-2 and a polysaccharide adjuvant. Here, IC28 and mannan were both covalently conjugated with RBD from E. coli. The conjugate (RBD-IC28-M) elicited high RBD-specific IgG titers, and a neutralization antibody titer of 201.4. It induced high levels of Th1-type cytokines (IFN-γ) and Th2-type cytokines (IL-5 and IL-10), along with high antigenicity and no apparent toxicity to the organs. The mouse sera of the RBD-IC28-M group competitively interfered with the interaction of RBD and ACE2. Thus, conjugation with IC28 and mannan additively enhanced the humoral and cellular immunity. Our study was expected to provide the feasibility to develop an affordable, easily scalable, effective vaccine SARS-CoV-2 vaccine.

The role of Fe3O4@biochar as electron shuttle in enhancing the biodegradation of gaseous para-xylene by aerobic surfactant secreted strains.

To study the role of electron shuttles in accelerating the biodegradation of volatile organic compounds (VOCs) and provide theoretical support for purification of waste gas containing PX, two self-producing biosurfactant strains were used to improve solubility, and the magnetic Fe3O4@biochar composites were prepared as electron shuttles to accelerate extracellular electron transfer during the process of para-xylene (PX) biodegradation. The composites were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The biodegradation time of PX by Enterobacter sp. HN01 and Klebsiella sp. HN02 decreased from 192 h to 12 h and 120 to 12 h, and approximately 93.75% and 90.00% of the removal times were saved after the addition of the composites. Furthermore, the effects of Fe3O4@biochar on the bacterial biosurfactant secretion, self-enzyme activity, and bacterial growth inhibition by PX were explored. The electron transport capacity of Fe3O4@biochar was 4.583 mmol·e-/g detected by mediated electrochemical reduction and mediated electrochemical oxidation, and possible electron transport pathways were revealed. The possible products of PX biodegradation by HN01 and HN02 were determined through gas chromatography-mass spectrometry. The molecular structure of PX was deduced through density functional theory calculation to validate the key product. Results indicated that Fe3O4@biochar can be used as an electronic shuttle to accelerate extracellular electron transfer and significantly improve VOCs removal rate.

High-order harmonics generation in the laser-induced lead-free perovskites-containing plasmas.

High-order harmonics generation in the laser-induced plasmas produced on the surfaces of lead-free perovskites is studied. We analyze the harmonics generation in (CH3NH3)2CuCl4 and (CH3NH3)2CuBr4 plasmas during their ablation by the femtosecond, picosecond, and nanosecond pulses. The modifications of the high-order harmonics spectra are studied using the -color pump scheme (800 nm and 400 nm, 40 fs pulses). The influence of the variations of laser chirp and pulse duration on the dynamics of high-order harmonics generation is examined. The spectral shift, chirp-related harmonic cutoff scaling, and the role of the pulse duration of converting and heating laser radiation are examined at different conditions of plasma formation and harmonic generation. The dependencies of the pulse duration and the fluence of heating pulses on the harmonic's blue shift are found. The effect of harmonics broadening and splitting on the two red- and blue-shifted components is demonstrated.

Newly isolated Enterobacter cloacae sp. HN01 and Klebsiella pneumoniae sp. HN02 collaborate with self-secreted biosurfactant to improve solubility and bioavailability for the biodegradation of hydrophobic and toxic gaseous para-xylene.

The gas-liquid mass transfer rate of hydrophobic volatile organic compounds (VOCs) is the limiting step in a biological treatment system. The present study aimed to utilize self-producing biosurfactants to enhance the bioavailability of hydrophobic gaseous VOCs. Two novel gram-negative rod-shaped bacteria, Enterobacter cloacae strain HN01 and Klebsiella pneumoniae strain HN02 were successfully isolated from sewage sludge by using blood agar and methylene blue agar plates. The two strains can use para-xylene (PX), a hydrophobic VOC model, as the only carbon source for biosurfactant production. Both strains can produce glycolipid biosurfactants, as confirmed by the emulsification index, Nuclear magnetic resonance, and Fourier transform infrared spectroscopy. Results indicated that PX can be completely decomposed at an initial concentration of 15.50 mg L-1, pH value of 7.0, and temperature of 30 °C within 36 h. The Yano model is suitable for the prediction of the growth kinetics of strains over the entire PX concentration range. Gas chromatography/mass spectrometry analysis indicated that PX was converted into four and four intermediates in the presence of the strains HN01 and HN02, respectively, and the possible mechanisms were proposed. The results can be used in purifying industrial hydrophobic gaseous VOCs and improving the bioavailability of VOCs with self-produced biosurfactants.