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Six corroded glazed pottery figurines, which excavated from the Qibi Ming Tomb of the Tang Dynasty in Xianyang, were selected to study the corrosion mechanism. Optical microscopy (OM), scanning electron microscopy equipped with energy dispersive X-ray spectrometry (SEM–EDS), Energy X-ray fluorescence spectrometry (EDX), and micro-Raman spectroscopy were applied to analyze the pristine composition of the glaze layer and pottery substrate, the composition and microstructure of corrosion products. The results indicate that lead-glazed pottery figurines are low-temperature PbO-CaO-SiO2 glaze, with Pb as the main flux, and Cu, Fe as the main colorant. The corrosion products include PbCO3, CaCO3, PbCO3·PbCl2, PbCl2, PbO2, and Si-rich layer. There are Aspergillus niger and Aspergillus sclerotiorum on the surface of glazed pottery. These microorganisms produce organic acids and mold spots on the surface of the pottery figurines, which in turn cause corrosion pits to form on the surface of the figurines. Chemical corrosion reactions mainly include dissolution–precipitation, combination reaction, and oxidation reaction. This article describes the corrosion process of lead-glazed pottery figurines and establishes corresponding corrosion models. This study provides new insights into the corrosion mechanism of lead-glazed pottery, which is of great significance for studying pottery corrosion. [ABSTRACT FROM AUTHOR]

Catalysts based on palladium are among the most effective in the complete oxidation of methane. Despite extensive studies and notable advances, the nature of their catalytically active species and conceivable structural dynamics remains only partially understood. Here, we combine operando transmission electron microscopy (TEM) with near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) and density functional theory (DFT) calculations to investigate the active state and catalytic function of Pd nanoparticles (NPs) under methane oxidation conditions. We show that the particle size, phase composition and dynamics respond appreciably to changes in the gas-phase chemical potential. In combination with mass spectrometry (MS) conducted simultaneously with in situ observations, we uncover that the catalytically active state exhibits phase coexistence and oscillatory phase transitions between Pd and PdO. Aided by DFT calculations, we provide a rationale for the observed redox dynamics and demonstrate that the emergence of catalytic activity is related to the dynamic interplay between coexisting phases, with the resulting strained PdO having more favorable energetics for methane oxidation. Palladium-based catalysts are highly effective for the complete oxidation of methane. Here, the authors employ operando transmission electron microscopy, near-ambient pressure X-ray photoelectron spectroscopy, and density functional theory calculations to investigate the active state and catalytic function of Pd nanoparticles in methane oxidation. [ABSTRACT FROM AUTHOR]

The antibacterial activity of Cinnamaldehyde against Methicillin-resistant Staphylococcus aureus in Bovine Mastitis is investigated in this study, providing insights into inhibition mechanisms and elucidating the effects on bacterial cell membranes. The Minimum Inhibitory Concentration and Minimum Bactericidal Concentration were determined in this study. In addition, growth curves and a time-kill assay were constructed to assess the antibacterial activity of Cinnamaldehyde. The study revealed that the MIC values ranged from 62.5 to 125 μg/mL, and the MBC values ranged from 125 to 250 μg/mL. The presence of sublethal concentrations of Cinnamaldehyde impeded bacterial growth, while high concentrations demonstrated a significant and rapid bactericidal effect. Subsequently, we examined cell morphology using SEM and TEM, evaluated membrane integrity via laser confocal fluorescence microscopy, and measured levels of β-galactosidase, extracellular DNA release, LDH activity, and ROS, to assess the antibacterial mechanism of Cinnamaldehyde. The findings indicated that with higher concentrations of Cinnamaldehyde, Methicillin-resistant Staphylococcus aureus demonstrated significant morphological alterations and disruption of both the cell wall and membrane. Furthermore, Cinnamaldehyde disrupted the integrity of membranes and increased permeability of the outer membrane in a manner dependent on its concentration. Cinnamaldehyde notably triggered the release of β-galactosidase, extracellular DNA, and LDH, in addition to elevating cellular ROS levels. Finally, the effect of Cinnamaldehyde on the transcription levels of genes related to cell membrane synthesis was assessed using RT-qPCR, and the effect of Cinnamaldehyde on the total protein content of Methicillin-resistant Staphylococcus aureus cells was assessed using WB. The RT-qPCR results showed that Cinnamaldehyde at 1xMIC notably upregulated the transcription levels of genes related to fatty acid biosynthesis in Methicillin-resistant Staphylococcus aureus cell membranes, with a significant or highly significant effect. The WB results showed that Cinnamaldehyde exerts its antibacterial action by suppressing protein expression in Methicillin-resistant Staphylococcus aureus. These findings illustrate that Cinnamaldehyde exerts a potent inhibitory effect on Methicillin-resistant Staphylococcus aureus, establishing a fundamental foundation for the potential use of Cinnamaldehyde essential oil as an antibacterial agent in the treatment of bovine mastitis, in accordance with established scientific standards. [ABSTRACT FROM AUTHOR]

Autotrophic denitrification technology has many advantages, including no external carbon source addition, low sludge production, high operating cost efficiency, prevention of secondary sewage pollution, and stable treatment efficiency. At present, the main research on autotrophic denitrification electron donors mainly includes sulfur, iron, and hydrogen. In these autotrophic denitrification systems, pyrite has received attention due to its advantages of easy availability of raw materials, low cost, and pH stability. When pyrite is used as a substrate for autotropic denitrification, sulfide (S2−) and ferrous ion (Fe2+) in the substrate will provide electrons to convert nitrate (NO3−) in sewage first to nitrite (NO2−), then to nitrogen (N2), and finally to discharge the system. At the same time, sulfide (S2−) loses electrons to sulfate (SO42−) and ferrous ion (Fe2+) loses electrons to ferric iron (Fe3+). Phosphates (PO43−) in wastewater are chemically combined with ferric iron (Fe3+) to form ferric phosphate (FePO4) precipitate. This paper aims to provide a detailed and comprehensive overview of the dynamic changes of nitrogen (N), phosphorus (P), and other substances in the process of sulfur autotrophic denitrification using iron sulfide, and to summarize the factors that affect wastewater treatment in the system. This work will provide a relevant research direction and theoretical basis for the field of sulfur autotrophic denitrification, especially for the related experiments of the reaction conversion of various substances in the system. [ABSTRACT FROM AUTHOR]

MTX in genetically distinctive Chinese psoriatic patients remains less explored. The present study aimed to determine the impact of HLA-Cw*06 on MTX response in a Chinese psoriasis patient population. A total of 204 patients with psoriasis were enrolled in this study. Clinical data and DNA samples from all patients were collected. The allele of HLA-Cw*06 genotyping was detected using direct Sanger sequencing. This study enrolled 204 patients with psoriasis, including 47 (23.04%) psoriatic arthritis patients, 157 (76.96%) patients free of psoriatic arthritis. Overall, 110 (53.92%) of all patients carried the HLA-Cw*06 allele. This frequency in patients with arthritis-free psoriasis was higher than that in those with psoriatic arthritis (58.59 vs. 38.30%, P = 0.014). After 8 weeks of MTX treatment, the arthritis-free psoriasis patients, who tested positive for the HLA-Cw*06 allele, showed significant improvement compared to those who tested negative (For PASI50, 78.57 vs. 55.22%, P = 0.02, and for PASI75, 51.11 vs. 34.33%, P = 0.036). The psoriatic arthritis-free patients who carried the HLA-Cw*06 allele in combination with the ABCB1 rs1045642 CC genotype showed the highest improvement. A regression model containing HLA-Cw*06, rs1045642T > C, and initial PASI scores was used to construct the efficacy prediction model of MTX, which yielded AUC values of 73.2 and 75.6% for PASI50 and PASI75 to MTX, respectively, in arthritis-free psoriasis patients. The HLA-Cw*06 allele is associated with optimal response to MTX treatment in arthritis-free Chinese psoriasis patients. When combined with clinical indicators, the polymorphism explained more than 75% of the individual efficacy differences. [ABSTRACT FROM AUTHOR]

In the process of mining belt transportation, various foreign objects may appear, which will have a great impact on the crusher and belt, thus affecting production progress and causing serious safety accidents. Therefore, it is important to detect foreign objects in the early stages of intrusion in mining belt conveyor systems. To solve this problem, the YOLOv4_GECA method is proposed in this paper. Firstly, the GECA attention module is added to establish the YOLOv4_GECA foreign object detection model in the mineral belt to enhance the foreign object feature extraction capability. Secondly, based on this model, the learning rate decay of restart cosine annealing is used to improve the foreign object image detection performance of the model. Finally, we collected belt transport image information from the Pai Shan Lou gold mine site in Shenyang and established a belt foreign body detection dataset. The experimental results show that the average detection accuracy of the YOLOv4_GECA method proposed in this paper is 90.1%, the recall rate is 90.7%, and the average detection time is 30 ms, which meets the requirements for detection accuracy and real-time performance at the mine belt transportation site. [ABSTRACT FROM AUTHOR]

Extensive research has been carried out for improved sensitivity of electroactive biofilm-based sensor (EAB-sensor), which is recognized as a useful tool in water quality early-warning. Antibiotic that is employed widely to treat infection has been proved feasible in this study to regulate the EAB and to increase the EAB-biosensor’s sensitivity. A novel composite electrode was prepared using azithromycin (AZM) and graphite powder (GP), namely AZM@GP electrode, and was employed as the anode in EAB-biosensor. Different dosages of AZM, i.e., 2 mg, 4 mg, and 8 mg, referred to as 0.25%, 0.5% and 1% AZM@GP were under examination. Results showed that EAB-biosensor was greatly benefited from appropriate dosage of AZM (0.5% AZM@GP) with reduced start-up time period, comparatively higher voltage output, more readable electrical signal and increased inhibition rate (30%–65% higher than control sensor with GP electrode) when exposing to toxic formaldehyde. This may be attributed to the fact that AZM inhibited the growth of non-EAM without much influence on the physiologic or metabolism activities of EAM under proper dosage. Further investigation of the biofilm morphology and microbial community analysis suggested that the biofilm formation was optimized with reduced thickness and enriched Geobacter with 0.5% AZM@GP dosage. This novel electrode is easily fabricated and equipped, and therefore would be a promising way to facilitate the practical application of EAB-sensors. [ABSTRACT FROM AUTHOR]

A series of degradable polyesters was synthesized via melt polymerization of 3,6-dioxaoctane-1,8-dioic acid and five different diols, catalyzed by antimony trioxide (Sb2O3). The polymers were characterized by FT-IR and 1H NMR spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) analysis. The polydispersity index (PDI = Mw/Mn) of the polyesters ranged from 1.55 to 1.99, the weight-average molecular weight (Mw) from 1.8 × 104 to 3.2 × 104 Da, the melting point from 63 to 123 °C, and the highest decomposition temperature observed was 363 °C. The influence of the structure of the polymer chain on hydrolytic degradability was investigated with tests performed at three different values of pH. The findings obtained provide useful insight for the molecular design and the synthesis of degradable polyesters. [ABSTRACT FROM AUTHOR]

The one-step fabricated laser-induced graphene (LIG) has the advantages of low cost, patterning of various desired geometries, and high sensitivity. However, the robustness of substrates imposes certain constraints on their applications in stretchable devices. In this paper, the substrate composed of polydimethylsiloxane (PDMS) and polyimide (PI) particles is proposed to serve as the platform to manufacture LIG. Ascribing to the inherent soft and stretchable attributes of the PI/PDMS composite substrate, the LIG-based sensors can fit complex 3D configurations or bear a mechanical tension over 15%. Notably, the fluence of the laser is experimentally and theoretically determined as the only principle to characterize the formation of conductive LIG on PI/PDMS composite greatly facilitating the selection of the allowable laser scanning parameters to form the desired LIG-based devices. Three demonstrations are conducted to highlight the superiority and the potential of this soft and stretchable LIG-based system in wearable electronics and soft robots. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is a rare but devastating event. Intravenous high-dose methotrexate (HD-MTX) is recommended as CNS prophylaxis, but the optimal timing and dose has not been elucidated. Here, we report a multicenter analysis of prophylactic HD-MTX administration for DLBCL. Two hundred eighty-four patients receiving HD-MTX either concurrent with each induction chemotherapy cycle (n = 221) or at the end of induction therapy (EOI, n = 63) were included. Patients with CNS-IPI scoring 4–6, and/or testicular involvement, and/or double/triple hit lymphoma, were stratified into the high-risk group and the others into the moderate-risk group. Concurrent HD-MTX was associated with increased risk of grade 3/4 treatment-related toxicity (OR,1.49; P = 0.006) and subsequent chemotherapy delays (OR, 1.87; P = 0.003) in multivariate analysis. With a median follow-up of 36.0 months, no significant difference in CNS relapse rate was identified between the concurrent and EOI groups (3.2% vs 4.8%, P = 0.34), even in the high-risk group. Analysis on systemic MTX dose suggested that high-dose MTX (≥ 2 g/m2) was associated with better CNS relapse control only in the high-risk group, but not in the moderate-risk group. This study may elucidate the superiority of EOI HD-MTX to some extent. High MTX dose (≥ 2 g/m2) may not be necessary for the moderate-risk patients. [ABSTRACT FROM AUTHOR]

Asthma-induced pulmonary fibrosis (PF) is an important public health concern that has few treatment options given its poorly understood etiology; however, the epithelial to mesenchymal transition (EMT) of pulmonary epithelial cells has been implicated to play an important role in inducing PF. Although previous studies have found atractylon (Atr) to have anti-inflammatory effects, whether Atr has anti-PF abilities remains unknown. The purpose of the current study was to validate the protective efficiency of Atr in both an animal model of ovalbumin (OVA)-induced asthma and an EMT model induced by transforming growth factor-β1 (TGF-β1) using TC-1 cells. The results of this study revealed that Atr treatment suppressed OVA-induced PF via fibrosis-related protein expression. Atr treatment suppressed OVA-induced circRNA-0000981 and TGFBR2 expression but promoted miR-211-5p expression. In vivo studies revealed that Atr suppressed TGF-β1-induced EMT and fibrosis-related protein expression via suppressing circRNA-0000981 and TGFBR2 expression. The results also suggested that the downregulation of circRNA-0000981 expression suppressed TGFBR2 by sponging miR-211-5p, which was validated by a luciferase reporter assay. Collectively, the findings of the present study suggest that Atr treatment attenuates PF by regulating the mmu_circ_0000981/miR-211-5p/TGFBR2 axis in an OVA-induced asthma mouse model. [ABSTRACT FROM AUTHOR]

Objectives: In this study, genome sequencing and metabolic analysis were used to identify and verify the key metabolic pathways for glucose and xylose utilization and fatty acid synthesis in the walnut endophytic bacterium (WEB) Bacillus subtilis HB1310. Results: The genome sequence of WEB HB1310 was generated with a size of 4.1 Mb and GC content of 43.5%. Genome annotation indicated that the Embden–Meyerhof–Parnas, pentose phosphate, and fatty acid synthesis pathways were mainly involved in mixed sugar utilization and lipid production. In particular, diverse and abundant fatty acid synthesis genes were observed in a higher number than in other Bacillus strains. The tricarboxylic acid cycle competitively shared the carbon flux flowing before 48 h, and the acetic acid fermentation competed after 72 h. Moreover, fatty acid synthase activity was highly correlated with lipid titer with a correlation coefficient of 0.9626, and NADPH might be more utilized for the lipid synthesis within 48 h. Conclusions: This study is the first attempt to explain the metabolic mechanism of mixed sugar utilization and lipid production based on genomic information, which provides a theoretical basis for the metabolic regulation of bacterial lipid production from lignocellulosic hydrolysates. [ABSTRACT FROM AUTHOR]

Background: We aimed to establish a predictive prognostic risk-stratification model for diffuse large B-cell lymphoma (DLBCL) in the rituximab era.Methods: The data of 1406 primary DLBCL patients from the Sun Yat-Sen University Cancer Center were analysed to establish a nomogram prognostic index (NPI) model for predicting overall survival (OS) based on pre-treatment indicators. An independent cohort of 954 DLBCL patients from three other hospitals was used for external validation.Results: Age, performance status, stage, lactate dehydrogenase, number of extranodal sites, BCL2, CD5 expression, B symptoms and absolute lymphocyte and monocyte count were the main factors of the NPI model and could stratify the patients into four distinct categories based on their predicted OS. The calibration curve demonstrated satisfactory agreement between the predicted and actual 5-year OS of the patients. The concordance index of the NPI model (0.794) was higher than the IPI (0.759) and NCCN-IPI (0.750), and similar results were obtained upon external validation. For CD5 + DLBCL patients, systemic treatment with high-dose methotrexate was associated with superior OS compared to R-CHOP-based immunochemotherapy alone.Conclusions: We established and validated an accurate prediction model, which performed better than IPI and NCCN-IPI for prognostic stratification of DLBCL patients. [ABSTRACT FROM AUTHOR]

In the model actinomycete strain, Streptomyces coelicolor, an orphan histidine kinase (HK) named OhkA (encoded by SCO1596), which belongs to bacterial two-component regulatory systems (TCSs), has been identified as being involved in the regulation of both antibiotic biosynthesis and morphological development. However, its cognate response regulator (RR) remains unknown due to its isolated genetic location on the genome, which impedes the elucidation of the mechanism underlying OhkA-mediated regulation. Here, we identified the orphan RR OrrA (encoded by SCO3008) as the cognate RR of OhkA according to mutant phenotypic changes, transcriptomics analysis, and bacterial two-hybrid experiment. Considering that the partner RR of the orphan HK is also orphan, a library of mutants with in-frame individual deletion of these functionally unknown orphan RR-encoding genes were generated. Through phenotypic analysis, it was found that the ∆orrA mutant exhibited similar phenotypic changes as that of the ∆ohkA mutant, showing increased production of actinorhodin (ACT) and undecylprodigiosin (RED), and pink colony surface. Further transcriptomics analysis showed these two mutants exhibited highly similar transcriptomics profiles. Finally, the direct interaction between OhkA and OrrA was revealed by bacterial two-hybrid system. The identification of the partner RR of OhkA lays a good foundation for an in-depth elucidation of the molecular mechanism underlying OhkA-mediated regulation of development and antibiotic biosynthesis in Streptomyces. Key points: • OrrA was identified as the partner RR of the orphan histidine kinase OhkA. • The ∆orrA and ∆ohkA mutants showed similar phenotype and transcriptomic profiling. • Specific interaction of OrrA and OhkA was revealed by bacterial two-hybrid system. [ABSTRACT FROM AUTHOR]

ATF3 is an essential transcription activator in regulating cancer-related genetic expression. To identify the role of ATF3 in ovarian tumor, we investigated the correlation between ATF3 expression and the clinicopathological properties using multiple database. The cBioPortal and GEPIA database displayed the clinical information of ovarian patients harboring or without harboring ATF3 mutation. Furthermore, we assessed the relationship between survival and ATF3 expression level using Kaplan-Meier plotter, which reveals that the ovarian patients with higher expression of ATF3 suffered the worse overall survival and progression-free survival. The differentially expressed genes were analyzed using gene ontology, protein-protein interaction network, and gene set enrichment analysis to identify the hub gene and critical pathways, significantly affecting the tumorigenesis of ovarian tumor. Finally, we assessed the correlation between ATF3 and immune cell infiltration using Tumor Immunoassay Resource (TIMER) database. The results demonstrated that higher expression has a positive correlation with macrophage infiltration, expression for M1- and M2-type macrophages. Our study suggests that ATF3 can regulate the cell cycle and heme-related oxidative phosphorylation process, and it may be a critical factor to regulate the macrophage cell to be infiltrated into ovarian cancer. ATF3 can be used as a biomarker for diagnosis and therapy of ovarian tumor. [ABSTRACT FROM AUTHOR]

Long-distance wireless power transmission can reduce the dependence of unmanned systems on energy storage systems, which is especially advantageous for unmanned aerial vehicles. This approach is key for building an integrated and uninterrupted air-to-ground power supply network. This paper introduces the technical characteristics of long-distance wireless power transmission systems, reports the development of such systems at home and abroad, and proposes technical indices and methods for performance evaluation of these systems. A test was conducted using a testing device, and the key parameters of the system performance were obtained. This work provides a solid foundation for the performance evaluation studies of long-distance wireless power transmission systems. [ABSTRACT FROM AUTHOR]

In this study, the aroma components of bead-shaped green teas were compared through headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry/olfactometry (GC–MS/O) coupled with chemometrics. A total of 62 volatile compounds were identified in 16 green tea samples. Notably, comparison of GC–MS/O and odour activity values (OAV) results revealed that nonanal, decanal, (E)-2-nonenal, β-ionone, and 1-octen-3-one were the most powerful aroma-active compounds that contributed to the aroma profile of the bead-shaped green teas. Furthermore, multivariate statistical techniques (such as principal component analysis, partial least squares-discriminant analysis, and hierarchical cluster analysis) were used to characterise the bead-shaped green teas according to their geographical origin and the flavour characteristics of their volatile compounds. Additionally, the variable importance in the projection method was used to identify 20 volatile markers that could successfully distinguish bead-shaped green teas on the basis of three flavour characteristics. The results of the analysis revealed that HS-SPME and GC–MS/O coupled with chemometrics can provide an effective method for characterising and classifying bead-shaped green teas. [ABSTRACT FROM AUTHOR]

We use neutron scattering to study Vanadium (hole)-doped LiFe1−xVxAs. In the undoped state, LiFeAs exhibits superconductivity at Tc = 18 K and transverse incommensurate spin excitations similar to electron overdoped iron pnictides. Upon Vanadium doping to form LiFe0.955V0.045, the transverse incommensurate spin excitations in LiFeAs transform into longitudinally elongated ones in a similar fashion to that of potassium (hole)-doped Ba0.7K0.3Fe2As2 but with dramatically enhanced magnetic scattering and elimination of superconductivity. This is different from the suppression of the overall magnetic excitations in hole-doped BaFe2As2 and the enhancement of superconductivity near optimal hole doping. These results are consistent with density function theory plus dynamic mean field theory calculations, suggesting that Vanadium doping in LiFeAs may induce an enlarged effective magnetic moment Seff with a spin crossover ground state arising from the inter-orbital scattering of itinerant electrons. [ABSTRACT FROM AUTHOR]

Lipopeptides are important non-ribosomal peptide synthetases (NRPSs) products with broad therapeutic potential in biotechnology and biopharmaceutical applications. Fatty acyl modifications in N-terminal of lipopeptides have attracted wide interest in the engineering processes of altered fatty acyl selectivity. In this study, we focused on the starter condensation domain of antibiotic A54145 (lptC1) and its indiscriminate selectivity of fatty acyl substrates, which results in multi-component products. Using in silico analysis, five site-directed mutations at protein–protein interface were identified with altered activity and selectivity towards wild type lptC1. The variants Y149W and A330T exhibited changed substrate selectivity to prefer longer branched chain fatty acyl substrate, while T16A and A350D showed improved selectivity for shorter linear chain fatty acyl substrates. Subsequently, molecular dynamics (MD) simulations were performed to analyze the impact of these residues on the changes of catalytic activity and conformation. Through in silico analysis, the altered binding free energy were coincident with the corresponding activity performance of the variants, and surface forces indicated that other factors or processes may influence the activity and selectivity. Moreover, the MD results revealed even altered active center conformations, implying the importance of these interface residues affected on distant active center thus reflected to catalysis activity. Based on the biochemistry and computational results, our work provides detailed insights from molecular and dynamics aspects into the role of C1's interface residues during complex NRPS biosynthesis machinery, prompting further rational engineering for lipopeptide catalysis. [ABSTRACT FROM AUTHOR]

Nano-NiO and bulk NiO were prepared from Ni(AC)2·4H2O by coordination precipitation using aqueous ammonia and by a solid state reaction, respectively. The nickel oxide particles were characterized by X-ray Diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that nano-sized NiO has a crystal phase with a standard face-centered cubic lattice structure, with a mean particle diameter of about 10 nm. The evaluation of the activity of nickel oxide nanoparticles in the catalytic hydrogenation of 7-methoxy-1-naphthylacetonitrile was carried out. The results demonstrate the efficient synthesis of the title compound by a one-pot catalytic hydrogenation and acetylation with NiO. The NiO nanoparticles displayed superior catalytic activity in the synthesis of agomelatine in the one-pot reaction.The total yield of agomelatine is over 81.8% with a purity of 99.2%, as determined by HPLC. The structure of agomelatine was confirmed by IR, MS, and 1H NMR analysis. [ABSTRACT FROM AUTHOR]

Abstract: A novel method combining terahertz time-domain spectroscopy (THz-TDS) with chemometrics was proposed for classification of sand samples from different deserts and grain sizes. THz-TDS combined with chemometrics was firstly utilized for identifying the source of sand samples and analyzing the sizes of sand granule. Terahertz time-domain transmittance spectra were collected and then Savitzky-Golay smoothing and orthogonal signal correction (OSC) approaches were used for spectral pretreatment. Principal component analysis, partial least squares discriminant analysis, and support vector machine were used to establish classification models of the sand samples. The prediction correctness ranged between 94 and 97%. Scanning electron microscopy was used to investigate the morphology of the sand samples. The sand samples were analyzed by energy dispersive spectroscopy and the elemental content distributions were obtained. Fourier transform infrared absorption spectra of the sand samples were also collected. THz-TDS combined with multivariate modeling methods provided reliable and useful information to determine the provenance of the sands originated from different deserts in northern China. This work reveals that THz-TDS can be a useful tool for classification of sand from different deserts. Graphical Abstract: THz-TDS combining chemometrics was first utilized for identifying sand sources. The sand samples from four different deserts in China were recognized. The sand samples with different particle sizes were classified. THz-TDS can be a useful tool for characterization of sand samples. [ABSTRACT FROM AUTHOR]

Biomanipulation of filter-feeding bivalves or fish can serve as complementary measures to zooplankton manipulation approach in lakes dominated by large-sized algae. A laboratory grazing experiment was conducted to compare the selective grazing of benthic bivalves (Hyriopsis cumingii) and planktivorous fish (silver carp) on particle size and algae species. Their combination grazing effects were also detected. The results showed that the clearance rates of silver carp were higher than that of H. cumingii, and that silver carp preferred particles in the 30-50 and 50-100 μm size fraction whereas H. cumingii did not show a significant selective grazing on seston size. Furthermore, the differences between the selective grazing of H. cumingii and silver carp on algae species were detected. Some algae species, which had not been digested well by silver carp, were not detected in H. cumingii’s pseudofeces. Similarly, some algal species in the pseudofeces of bivalves were not detected in the feces of fish. Moreover, the combined clearance rates of H. cumingii and silver carp (ranging from 12.14 to 95.99 mL g DW−1 h−1) were higher than that of single filter feeder (0.47 to 10.18 mL g DW−1 h−1). We suggest therefore that when using biomanipulation measures to control large-sized algal overgrowth, a combination of different filter feeders may be a better way considering their collaborative grazing in both particle size and algae species selectivity. [ABSTRACT FROM AUTHOR]

Main conclusion: Hydrogen peroxide-responsive pathways in roots of alkaligrass analyzed by proteomic studies and PutGLP enhance the plant tolerance to saline-, alkali- and cadmium-induced oxidative stresses.Oxidative stress adaptation is critical for plants in response to various stress environments. The halophyte alkaligrass (Puccinellia tenuiflora) is an outstanding pasture with strong tolerance to salt and alkali stresses. In this study, iTRAQ- and 2DE-based proteomics approaches, as well as qRT-PCR and molecular genetics, were employed to investigate H2O2-responsive mechanisms in alkaligrass roots. The evaluation of membrane integrity and reactive oxygen species (ROS)-scavenging systems, as well as abundance patterns of H2O2-responsive proteins/genes indicated that Ca2+-mediated kinase signaling pathways, ROS homeostasis, osmotic modulation, and transcriptional regulation were pivotal for oxidative adaptation in alkaligrass roots. Overexpressing a P. tenuiflora germin-like protein (PutGLP) gene in Arabidopsis seedlings revealed that the apoplastic PutGLP with activities of oxalate oxidase and superoxide dismutase was predominantly expressed in roots and played important roles in ROS scavenging in response to salinity-, alkali-, and CdCl2-induced oxidative stresses. The results provide insights into the fine-tuned redox-responsive networks in halophyte roots. [ABSTRACT FROM AUTHOR]

Thermosensitive LCST phase separation behaviors of poly( N-isopropylacrylamide) (PNIPAM) aqueous solutions have been investigated by a power compensation differential scanning calorimetry which can be subjected to relatively high cooling and heating scanning rates. Significant difference in the thermal properties is observed in four different concentration regions. The typical demixing enthalpy recovery behavior is observed in region III and IV, but cannot be observed in region II. In concentration region I, only one concentration-dependent glass transition behavior can be observed. The distinct thermal features in different concentration regions were interpreted by the complexity of chemical structure, and there are more than one polar groups in the repeating unit of PNIPAM, hydrogen bonded with different numbers of water molecules in different concentration regions. The endothermic phase separation process involved both a chemical process of the breakage of hydrogen bonding between polymer and water molecules and a physical process of the coil-to-globule transition of swelling polymer chains. [ABSTRACT FROM AUTHOR]

Bacterial prodigiosins are red-colored secondary metabolites with multiple activities, such as anticancer, antimalarial and immunosuppressive, which hold great potential for medical applications. In this study, dramatically enhanced prodigiosins (RED) production in Streptomyces coelicolor was achieved by combinatorial metabolic engineering, including inactivation of the repressor gene ohkA, deletion of the actinorhodin (ACT) and calcium-dependent antibiotic (CDA) biosynthetic gene clusters (BGCs) and multi-copy chromosomal integration of the RED BGC. The results showed that ohkA deletion led to a 1-fold increase of RED production over the wild-type strain M145. Then, the ACT and CDA BGCs were deleted successively based on the Δ ohkA mutant (SBJ101). To achieve multi-copy RED BGC integration, artificial ΦC31 attB site(s) were inserted simultaneously at the position where the ACT and CDA BGCs were deleted. The resulting strains SBJ102 (with a single deletion of the ACT BGC and insertion of one artificial attB site) and SBJ103 (with the deletion of both BGCs and insertion of two artificial attB sites) produced 1.9- and 6-fold higher RED titers than M145, respectively. Finally, the entire RED BGC was introduced into mutants from SBJ101 to SBJ103, generating three mutants (from SBJ104 to SBJ106) with chromosomal integration of one to three copies of the RED BGC. The highest RED yield was from SBJ106, which produced a maximum level of 96.8 mg g cell dry weight, showing a 12-fold increase relative to M145. Collectively, the metabolic engineering strategies employed in this study are very efficient for the construction of high prodigiosin-producing strains. [ABSTRACT FROM AUTHOR]

Otitis media with effusion (OME) is a common disease and eustachian tube (ET) dysfunction is widely known to be related to the incidence of OME; however, objective evaluation tools for ET function are lacking. To evaluate ET openings by tubomanometry (TMM) in adult patients with otitis media with effusion (OME), the ET patency of 123 ears, including 63 ears of OME patients and 60 control ears, were tested using TMM and tympanometry. ET patency was evaluated by the R value and ET score, and was compared to the tympanogram results. The eustachian tube dysfunction questionnaire (ETDQ-7) was used to assess the severity of the symptoms in OME patients. The results showed that the rates of restricted opening or blocked ET under pressures of 30, 40, and 50 mbar by TMM testing were 10, 5, and 0 %, respectively (control group) and 76.19, 66.7, and 57.97 %, respectively (OME group) ( p < 0.05 for all pressure groups). However, the rates were 77.42, 71.97, and 61.29 % in the type B tympanogram group, and 75, 62.5, and 46.87 % in the type C tympanogram group; no significant difference was found at each testing pressure ( p = 0.821, 0.246, and 0.516; respectively) between these tympanogram groups. The mean ETDQ-7 score in OME patients was 16.40 ± 10.72, which was significantly negatively correlated with the ET score at 30 and 40 mbar (30 mbar: correlation coefficient −0.29, p = 0.025; 40 mbar: correlation coefficient −0.28; p = 0.030), but not at 50 mbar (correlation coefficient −0.013, p = 0.924). These findings showed that ET blockage or delayed opening were found in most adult patients with OME when evaluated by this innovative and semi objective TMM, testing pressures should be considered when assessing the results of TMM in OME patients. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) have attracted much attention of the research community in the recent years. Due to their highly tumorigenic and drug-resistant properties, CSCs represent important targets for developing novel anticancer agents and therapeutic strategies. CSCs were first described in hematopoietic malignancies and subsequently identified in various types of solid tumors including brain, breast, lung, colon, melanoma, and ovarian cancer. CSCs possess special biological properties including long-term self-renewal capacity, multi-lineage differentiation, and resistance to conventional chemotherapy and radiotherapy. As such, CSCs are considered as a major source of residual disease after therapy leading to disease occurrence. Thus, it is very important to understand the cellular survival mechanisms specific to CSCs and accordingly develop effective therapeutic approaches to eliminate this subpopulation of cancer cells in order to improve the treatment outcome of cancer patients. Possible therapeutic strategies against CSCs include targeting the self-renewal pathways of CSCs, interrupting the interaction between CSCs and their microenvironment, and exploiting the unique metabolic properties of CSCs. In this review article, we will provide an overview of the biological characteristics of CSCs, with a particular focus on their metabolic properties and potential therapeutic strategies to eliminate CSCs. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for simultaneous determination of 5-hydroxytryptamine (5-HT) and dopamine (DA) was developed in this paper based on an ionic liquid functionalized-graphene (IL-graphene) modified glassy carbon electrode. Transmission electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used to characterize the formation of the IL-graphene composites. Due to functionalization of the ionic liquid, IL-graphene can not only be dispersed well in aqueous solutions, but also exhibit a strong positive charge. Cyclic voltammetry and differential pulse voltammetry results demonstrated that 5-HT and DA can be detected selectively and sensitively at the constructed electrode with peak-to-peak separation about 164 mV. Under the optimized condition, the linear responses were obtained in the range of 2.0 × 10 to 1.0 × 10 M with a detection limit of 6.7 × 10 M for 5-HT, and in the range of 1.0 × 10 to 1.0 × 10 M with a detection limit of 3.3 × 10 M for DA (S/N = 3), respectively. Moreover, the designed sensor was further applied to the simultaneous determination 5-HT and DA levels in human serum samples with reliable recovery. The excellent performance of this sensor was ascribed to the network-like structure of IL-graphene which provided large surface area to contact 5-HT or DA. [ABSTRACT FROM AUTHOR]

Activation of AMP-activated protein kinase (AMPK) plays an important role in cardiovascular protection. It can inhibit arterial smooth muscle cell proliferation and cardiac fibroblast collagen synthesis induced by anoxia. However, the role of AMPK-dependent signalling cascades in the pulmonary vascular system is currently unknown. This study aims to determine the effects of AMPK on pulmonary hypertension and pulmonary vessel remodelling induced by hypoxia in rats using in vivo and in vitro studies. In vivo study: pulmonary hypertension, right ventricular hypertrophy and pulmonary vascular remodelling were found in hypoxic rats. Meanwhile, AMPKα and phosphorylated AMPKα were increased markedly in pulmonary arterioles and lung tissues. Mean pulmonary arterial pressure, index of right ventricular hypertrophy and parameters of pulmonary vascular remodelling, including vessel wall area/total area, density of nuclei in medial smooth muscle cells, and thickness of the medial smooth muscle cell layer were markedly suppressed by AICAR, an AMPK agonist. In vitro study: the expression of AMPKα and phosphorylated AMPKα was increased in pulmonary artery smooth muscle cells (PASMCs) under hypoxic conditions. The effects of PASMC proliferation stimulated by hypoxia were reinforced by treatment with Compound C, an AMPK inhibitor. AICAR inhibited the proliferation of PASMCs stimulated by hypoxia. These findings suggest that AMPK is involved in the formation of hypoxia-induced pulmonary hypertension and pulmonary vessel remodelling. Up-regulating AMPK can contribute to decreasing pulmonary vessel remodelling and pulmonary hypertension induced by hypoxia. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the association of polymorphisms in the promoter region of the IL-10 gene with the risk of inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). Fifteen studies (3,693 cases and 4,574 controls) were included in a meta-analysis of association between IL-10 −1082G/A, −819C/T and −592C/A polymorphisms, and IBD, CD and UC using allele contrast and the recessive, dominant, and additive models. Hardy-Weinberg equilibrium was confirmed for each study. Heterogeneity and study quality were investigated using stratification analyses and sensitivity analyses. Polymorphism −1082G/A showed significant association with CD, with odds ratios (ORs) for the GG + GA genotype and GG versus AA genotype of 1.278 (1.004-1.627) and 1.238 (1.027-1.492) in all subjects. Significant associations were found in the Caucasian subgroup using the allele contrast, dominant, and additive models. C-allele carriers of the −819C/T polymorphism were at increased risk of IBD (OR 1.093, 95 % CI 1.004-1.190). Association with the −819C/T polymorphism was also found in Caucasians with CD (C vs. T: OR 1.104, 95 % CI 1.010-1.206; CC + CT vs. TT: OR 1.328, 95 % CI 1.006-1.754; CC vs. TT: OR 1.339, 95 % CI 1.008-1.778), and with UC (CC vs. CT + TT: OR 1.188, 95 % CI 1.019-1.385). No significant association was found between the −592C/A polymorphism and IBD, CD or UC. In conclusion, the meta-analysis demonstrated clear association between the IL-10 polymorphisms −1082G/A and −819C/T and the risk of IBD. [ABSTRACT FROM AUTHOR]

The present study examines the clinical significance of serum neuron-specific enolase (NSE) in patients with non-germinal center B-cell type (non-GCB) of diffuse large B-cell lymphoma (DLBCL) that received rituximab chemotherapy. Serum NSE values were measured using electrochemiluminescence assay in 53 patients. About 54.7% of the DLBCL patients had positive expression of serum NSE (>15.20 ng/ml), which closely correlated with performance status, serum LDH level, B symptoms, IPI scores, and Ann-Arbor stages ( P < 0.05). The mean serum NSE value in patients with non-GCB subtype of DLBCL was significantly higher than that of GCB subtype of DLBCL ( P = 0.001), and among patients in non-GCB subtype group, there was significant difference in the 5-year OS rate between NSE-positive group and negative group (28.3% vs. 81.6%, P < 0.001). Furthermore, serum NSE level was found to be an independent prognostic factor in patients with non-GCB subtype. Serum NSE may be a novel marker of disease aggressiveness as well as a prognostic factor for non-GCB subtype of DLBCL in the era of rituximab. [ABSTRACT FROM AUTHOR]

A small in-plane external uniaxial pressure has been widely used as an effective method to acquire single domain iron pnictide BaFe2As2, which exhibits twin-domains without uniaxial strain below the tetragonal-to-orthorhombic structural (nematic) transition temperature Ts. Although it is generally assumed that such a pressure will not affect the intrinsic electronic/magnetic properties of the system, it is known to enhance the antiferromagnetic (AF) ordering temperature TN (< Ts) and create in-plane resistivity anisotropy above Ts. Here we use neutron polarization analysis to show that such a strain on BaFe2As2 also induces a static or quasi-static out-of-plane (c-axis) AF order and its associated critical spin fluctuations near TN/Ts. Therefore, uniaxial pressure necessary to detwin single crystals of BaFe2As2 actually rotates the easy axis of the collinear AF order near TN/Ts, and such effects due to spin-orbit coupling must be taken into account to unveil the intrinsic electronic/magnetic properties of the system. BaFe2As2 is a parent compound for iron based superconductors, and this has motivated extensive study of its magnetic and electronics properties. Here, using neutron polarisation analysis, the authors demonstrate the critical importance of spin-orbit coupling to properties of BaFe2As2. [ABSTRACT FROM AUTHOR]

Mosquitocidal Bacillus thuringiensis (Bt) strain S2160-1 was proposed to be an alternative to Bacillus thuringiensis subsp. israelensis (Bti). Discovering and validating a toxic gene by experimentation was a complex and time-consuming task, which can benefit from high-throughput sequencing analysis. In this research, we predicted and identified toxic proteins in the strain S2160-1 based on the draft whole genome sequence data. Through a local BLASP, 46 putative toxins were identified in S2160-1 genome, by searching against a customized B. thuringiensis toxin proteins database containing 653 protein or peptide sequences retrieved from public accessible resources and PCR/clone results in our laboratory (e value = 1e − 5). These putative toxins consist of 42 to 1216 amino acids. The molecular weights are ranged from 4.86 to 137.28 kDa. The isoelectric point of these candidate toxins varied from 4.3 to 10.06, and 16 out of which had a pH greater than 7.0. The analysis of tertiary structure and PFAM domain showed that 12 potential plasmid toxins may share higher similarity (9/12 QMEAN4 score > 0.3) with known Bt toxins. In addition, functional annotation indicated that these 12 potential toxins were involved in “sporulation resulting in formation of a cellular spore” and “toxin activity”. Moreover, multiple alignment and phylogenetic analysis were carried out to elucidate the evolutionary relationship among 101 known crystal or toxin proteins from public database and them with MEGA 6.0. It indicated that PS2160P2_1 and PS2160P2_153 may be potential Cry4-like toxins in Bt S2160-1. This research may lay the foundation for future functional analysis of Bt S2160-1 toxin proteins to reveal their biological roles. [ABSTRACT FROM AUTHOR]