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The location and development of porphyry copper deposits is a key issue for the mining industry. In this study, the Gondwana metallogenic belt was chosen as the study area to compare multiple methods for extracting multi-source geological elements to maximize the accuracy of the datasets used for mining evaluation and to use them to assess porphyry copper mineability. By comparison, a support vector machine (SVM) with an overall classification accuracy of 97.6573% and a Kappa coefficient of 0.9806 was used to extract the lithological distribution of the study area. Spectral feature-enhanced principal component analysis (EPCA) was combined with ASTER images to extract alteration information, with significant improvements in spatial aggregation and overall area compared to other alteration extraction methods, while a hierarchical alteration interpolation method was proposed to overcome the limitations of relying solely on remote sensing images to obtain surface alteration information and qualitatively extend deep alteration information. In addition, by overlaying various geoscientific factors affecting copper mineralization and mining, a Pearson correlation analysis is carried out in conjunction with currently proven or mined copper occurrences, and a weight of evidence approach is used to classify the study area into four mineability classes, which is important for narrowing down potential target areas for mineral exploration and assessing their mining value while contributing to an in-depth understanding of the role of geological elements in mineralization and development.

To explore the key antibiofilm components of green Sichuan pepper essential oil (GPEO) against the spoilage microorganism Bacillus amyloliquefaciens and their intracellular targets, a molecular structure database of GPEO components and a collection of the molecule structures of target proteins related to the biofilm formation of B. amyloliquefaciens were created based on related literature data, and the CB-DOCK2 servicer was used to perform molecular docking of the active components of GPEO to biofilm formation-related target proteins. Furthermore, the key antibiofilm components of GPEO were selected based on their docking affinity and their potential targets were explored. Finally, in vitro experiments and crystal violet staining were conducted to confirm the antibiofilm effects of two key active components of GPEO, caryophyllene oxide and β-caryophyllene, against B. amyloliquefaciens. Molecular docking results showed that 24 volatile components of GPEO had different affinities to 58 targets associated with the biofilm formation of B. amyloliquefaciens, among which β-caryophyllene and caryophyllene oxide could tightly bind to ComP and RapC through intermolecular forces such as hyperconjugation, hydrophobic interaction and van der Waals force, forming a stable conformation. In vitro experiments showed that the minimal inhibitory concentrations (MICs) of caryophyllene oxide and β-caryophyllene against the biofilm of B. amyloliquefaciens were 6.0 and 2.0 mg/mL, respectively. Both compounds interfered with the swimming motility of this bacterium, reduced the initial cell adhesion and auto-aggregation ability, and altered the cell surface hydrophobicity. These results provide feasible strategies to help decipher the intracellular molecular mechanisms related to the biological activity of plant essential oil.

Background: The only human cathelicidin, LL-37, and the innate defense regulator peptide IDR-1, which have been proven to have antimicrobial activity, represent essential elements of immunity. Our previous study showed that the peptide LL-37 was protective in vitro to attenuate LTA-induced inflammatory effects. Methicillin-resistant staphylococcus aureus (MRSA) causes a multitude of serious and sometimes life-threatening diseases around the globe. However, the effect of LL-37 and IDR-1 in MRSA-induced pneumonia is unknown. In the present study, we explored the potential of LL-37 and IDR-1 in ameliorating MRSA-induced pneumonia in vivo. Methods: C57BL/6 mice were randomly divided into four groups and perfused intratracheally with PBS, peptide, MRSA and MRSA plus peptide, respectively. Pulmonary tissue pathology, ELISA and quantitative RT-PCR were employed. The relative signal pathways were further explored by western blot analysis. Results: Pathological analysis of the lung tissue sections demonstrated that, when compared with the MRSA-treated group, both the LL-37 and IDR-1 could ameliorate the MRSA-induced pneumonia. The phosphorylation of JNK and Akt were markedly decreased in the peptide plus MRSA-treated group compared with the MRSA-treated group. Furthermore, both of them also reduced TNF-α and IL-6 production in the bronchoalveolar lavage fluid (BALF) and serum in vivo. Conclusion: We report the first evidence of peptides inhibiting inflammation, decreasing the release of inflammatory cytokines and restoring pulmonary function in vivo. The antimicrobial peptide LL-37 and IDR-1 could ameliorate MRSA-induced pneumonia by exerting an anti-inflammatory property and attenuating pro-inflammatory cytokine release, thus providing support for the hypothesis that both innate and synthetic peptides could protect against MRSA in vivo.

Abstract Objective Even though extensive studies have surveyed long non-coding RNA (lncRNA)-related networks in hypoxic-ischemic brain damage (HIBD), the concrete function of lncRNA H19 (H19) in HIBD is still in ambiguity. Therein, this work intends to decipher H19-related network of microRNA (miR)-140-5p and signal transducer and activator of transcription 3 (STAT3) in HIBD. Methods Brain microvascular endothelial cells (BMECs) from BALB/c mice were isolated and induced by oxygen glucose deprivation (OGD). OGD-induced BMECs were transfected with depleted or restored H19, miR-140-5p or STAT3, and cell apoptosis, migration and angiogenesis were examined. H19, miR-140-5p and STAT3 expression and their internal connections were tested. Results H19 and STAT3 were overexpressed while miR-140-5p was down-regulated in OGD-induced BMECs. H19 or STAT3 knockdown, or miR-140-5p restoration repressed apoptosis and improved migration and angiogenesis of OGD-induced BMECs. MiR-140-5p restoration negated the impacts of up-regulated H19 on OGD-induced BMECs. H19 bound to miR-140-5p to modulate STAT3 expression. Conclusion The work illustrates that depleting H19 or STAT3 or restoring miR-140-5p attenuates HIBD and supplies a novel perspective for HIBD management.

Metal oxide films are essential in most electronic devices, yet they are typically deposited at elevated temperatures by using slow, vacuum-based processes. We printed native oxide films over large areas at ambient conditions by moving a molten metal meniscus across a target substrate. The oxide gently separates from the metal through fluid instabilities that occur in the meniscus, leading to uniform films free of liquid residue. The printed oxide has a metallic interlayer that renders the films highly conductive. The metallic character of the printed films promotes wetting of trace amounts of evaporated gold that would otherwise form disconnected islands on conventional oxide surfaces. The resulting ultrathin (<10 nanometers) conductors can be patterned into flexible circuits that are transparent, mechanically robust, and electrically stable, even at elevated temperatures. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the role of N-acyl homoserine lactones (AHLs) in the regulation of swimming motility of Hafnia alvei H4 and its biofilm formation on 96-well plate, glass and stainless-steel surfaces. The luxI gene, which codes for an enzyme involved in AHL synthesis, was deleted to generate a luxI mutant (ΔluxI). The mutant produced no AHL, and the relative expression of the luxR gene was significantly (P < 0.05) decreased. In addition, qRT-PCR analysis showed that the relative expression of the luxR gene in ΔluxI was stimulated by the presence of exogenous AHLs (C4-HSL, C6-HSL, and 3-o-C8-HSL) added at concentrations ranging from of 50–250 μg/ml. Among the three AHLs, C6-HSL had the strongest effect. The ability of ΔluxI to form biofilm on 96-well plate, glass and stainless-steel surfaces was significantly reduced (P < 0.05) compared with the wild type (WT), but was increased when provided with 150 μg/ml C4-HSL, whereas C6-HSL and 3-o-C8-HSL had no effect. Scanning electron microscopy analysis of the biofilm revealed less bacteria adhering to the surface of stainless-steel and fewer filaments were found binding to the cells compared with the WT. Furthermore, ΔluxI also exhibited significant (P < 0.05) decrease in the expression of biofilm- and swimming motility-related genes, flgA, motA and cheA, consistent with the results observed for biofilm formation and swimming motility. Taken together, the results suggested that in H. alvei H4, C4-HSL may act as an important molecular signal through regulating the ability of the cells to form biofilm, as well as through regulating the swimming motility of the cell, and this could provide a new way to control these phenotypes of H. alvei in food processing.

Vibrio parahaemolyticus isolated from seafood is a pathogenic microorganism that leads to several acute diseases that are harmful to our health and is frequently transmitted by food. Therefore, there is an urgent need for the control and suppression of this pathogen. In this paper, transcriptional analysis was used to determine the effect of treatment with benzyl isothiocyanate (BITC) extracted from cruciferous vegetables on V. parahaemolyticus and to elucidate the molecular mechanisms underlying the response to BITC. Treatment with BITC resulted in 332 differentially expressed genes, among which 137 genes were downregulated, while 195 genes were upregulated. Moreover, six differentially expressed genes (DEGs) in RNA sequencing studies were further verified by quantitative real-time polymerase chain reaction (qRT-PCR). Genes found to regulate virulence encoded an l-threonine 3-dehydrogenase, a GGDEF family protein, the outer membrane protein OmpV, a flagellum-specific adenosine triphosphate synthase, TolQ protein and VirK protein. Hence, the results allow us to speculate that BITC may be an effective control strategy for inhibiting microorganisms growing in foods.

The influence of 11 kinds of oxygen-containing sulfur flavor molecules was examined on β-carotene stability under UVA irradiation in ethanol system. Both the effects of sulfides on dynamic degradation of β-carotene and the relation between structure and effect were investigated. The oxidation products of β-carotene accelerated by sulfides under UVA irradiation were also identified. The results indicated that the disulfides had more obvious accelerative effects on the photodegradation of β-carotene than mono sulfides. The degradation of β-carotene after methyl (2-methyl-3-furyl) disulfide (MMFDS), methyl furfuryl disulfide (MFDS) and bis(2-methyl-3-furyl) disulfide (BMFDS) exposure followed first-order kinetics. Furan-containing sulfides such as MMFDS and BMFDS showed more pronounced accelerative effects than their corresponding isomers. The oxidation products were identified as 13-cis-β-carotene, 9,13-di-cis-β-carotene and all-trans-5,6-epoxy-β-carotene. These results suggest that both the sulfur atom numbers and the furan group in oxygen-containing sulfides play a critical role in the photooxidation of β-carotene.

Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm, the relationship between lightning activity and four satellite digital products; blackbody radiation brightness temperature (TBB), cloud top temperature (CTT), cloud top height (CTH) and cloud top pressure (CTP) was quantitatively analyzed. The following conclusions were obtained; (1) at lightning location, 90. 5% of TBB values were less than 214.1 K; 88.5% of CTT values were less than 207.7 K; 88.5% of CTP values were less than 137.7 hPa, and 88.5% of CTH values were greater than 14 872 m. At location without lightning, 92. 5% of TBB values were greater than 214.1 K; 90.4% of CTT values were greater than 207.1 K; 89% of CTP values were greater than 137.7 hPa, and 92% of CTH values were less than 14 872 m. (2) Lightning activity was concentrated in the cloud area with TBB between 190 -210 K, CTT between 185 -210 K, CTP between 50 - 150 hPa and CTH between 12 - 18 km. Lightning intensity was roughly positively correlated with TBB, CTT and CTP, and negatively correlated with CTH. With the increase of CTH, lightning intensity decreased. (3) TBB, CTT, CTP and CTH can well indicate the location and activity frequency of lightning in thunderstorm weather. [ABSTRACT FROM AUTHOR]

This study aimed to identify N-acylhomoserine lactone (AHL) produced by Hafnia alvei H4, which was isolated from spoiled instant sea cucumber, and to investigate the effect of AHLs on biofilm formation. Two biosensor strains, Chromobacterium violaceum CV026 and Agrobacterium tumefaciens KYC55, were used to detect the quorum sensing (QS) activity of H. alvei H4 and to confirm the existence of AHL-mediated QS system. Thin layer chromatography (TLC) and high resolution triple quadrupole liquid chromatography/mass spectrometry (LC/MS) analysis of the AHLs extracted from the culture supernatant of H. alvei H4 revealed the existence of at least three AHLs: N-hexanoyl-l-homoserine lactone (C6-HSL), N-(3-oxo-octanoyl)-l-homoserine lactone (3-oxo-C8-HSL), and N-butyryl-l-homoserine lactone (C4-HSL). This is the first report of the production of C4-HSL by H. alvei. In order to determine the relationship between the production of AHL by H. alvei H4 and bacterial growth, the β-galactosidase assay was employed to monitor AHL activity during a 48-h growth phase. AHLs production reached a maximum level of 134.6 Miller unites at late log phase (after 18 h) and then decreased to a stable level of about 100 Miller unites. AHL production and bacterial growth displayed a similar trend, suggesting that growth of H. alvei H4 might be regulated by QS. The effect of AHLs on biofilm formation of H. alvei H4 was investigated by adding exogenous AHLs (C4-HSL, C6-HSL and 3-oxo-C8-HSL) to H. alvei H4 culture. Biofilm formation was significantly promoted (p < 0.05) by 5 and 10 µM C6-HSL, inhibited (p < 0.05) by C4-HSL (5 and 10 µM) and 5 µM 3-oxo-C8-HSL, suggesting that QS may have a regulatory role in the biofilm formation of H. alvei H4.