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Background: The heterogeneity limits the effective application of immune checkpoint inhibitors for patients with stomach adenocarcinoma (STAD). Precise immunotyping can help select people who may benefit from immunotherapy and guide postoperative management by describing the characteristics of tumor microenvironment. Methods: Gene expression profiles and clinical information of patients were collected from ACRG and TCGA-STAD datasets. The immune subtypes (ISs) were identified by consensus clustering analysis. The tumor immune microenvironments (TIME) of each IS were characterized using a series of immunogenomics methods and further confirmed by multiplex immunohistochemistry (mIHC) staining in clinical samples. Two online datasets and one in-house dataset were utilized to construct and validate a prognostic immune-related gene (IRG) signature. Results: STAD patients were stratified into five reproducible ISs. IS1 (immune deserve subtype) had low immune infiltration and the highest degree of HER2 gene mutation. With abundant CD8+ T cells infiltration and activated cytotoxicity reaction, patients in the IS2 (immune-activated subtype) had the best overall survival (OS). IS3 and IS4 subtypes were both in the reactive stroma state and indicated the worst prognosis. However, IS3 (immune-inhibited subtype) was characterized by enrichment of FAP+ fibroblasts and upregulated TGF-β signaling pathway, while IS4 (activated stroma subtype) was characterized by enrichment of ACTA2+ fibroblasts. In addition, mIHC staining confirmed that TGF-β upregulated FAP+ fibroblasts were independent risk factor of OS. IS5 (chronic inflammation subtype) displayed moderate immune cells infiltration and had a relatively good survival. Lastly, we developed a nine-IRG signature model with a robust performance on overall survival prognostication. Conclusions: The immunotyping is indicative for characterize the TIME heterogeneity and the prediction of tumor prognosis for STADs, which may provide valuable stratification for the design of future immunotherapy. [ABSTRACT FROM AUTHOR]

The charge structure in the cutting area has an important practical engineering significance in improving the blasting performance and increasing the excavation work efficiency, especially in tunneling practices with soft and broken surrounding rocks. To contain the excessive damage in the tunnel face of the Meishan Iron Mine, the finite element program LS-DYNA is used to investigate the effect of the charge structure of cutting holes (with an air deck and without an air deck at the blasthole bottom) on the blasting performance in roadway excavation. Numerical results indicated that the blasthole bottom was seriously damaged by blasting under the condition of charge without an air deck. Accordingly, 80-mm bottom air deck length is determined based on analytical calculation, and a numerical simulation was conducted and showed that the air deck could effectively weaken the excessive damage around the blasthole bottom. Specifically, the peak pressure at the monitoring point (10 cm horizontally from the center of the blasthole bottom) with an air deck is 22.1 MPa, which is much smaller than that of the no-air-deck case of 207.1 MPa. The field experimental results indicated that the tunnel face was obviously damaged under the condition of holes without an air deck and the tunnel face was relatively flat under the condition of a blasthole bottom with an air deck, which is consistent with the numerical results. The workload for cleaning loose rock for the next excavation cycle in a 3.5 m advance was reduced from 40 min to around 25 min. [ABSTRACT FROM AUTHOR]

Rare earth dysprosium-doped Z-type hexaferrite were synthesized by the sol-gel method. The synthesized material has a uniform particle size and a typical hexagonal flake shape. The research results show that the samples have excellent soft magnetic properties, and the saturation magnetization of the samples increases gradually with the increase of the doping amount of Dy. In addition, it is also found that the doping of trace dysprosium has a significant effect on the improvement of microwave absorption properties of Z-type hexaferrite. Specifically, when the doping amount is x = 0.05, the sample not only exhibits an excellent reflection loss value of −52.6dB at 5.25 GHz, but also has a maximum effective absorption bandwidth (RL<−10dB) of 6.6 GHz, encompassing both C-band and X-band. When the amount of doping is excessive, an impurity phase will be generated, and the magnetic properties and microwave absorption properties of the material will be reduced, indicating that doping an appropriate amount of Dy3+ will improve the microwave absorption property of Z-type hexaferrite. [ABSTRACT FROM AUTHOR]

Rare earth elements and yttrium (REY) in coal deposits are considered promising alternative sources for these resources owing to their increasing global demand. This paper reports the geochemical characteristics of REY in the Late Permian coals from an underground K1a seam section of the Zhongliangshan coalfield in Chongqing, southwestern China. The mineralogy, degree of enrichment, distribution patterns, modes of occurrence, and sediment origin of REY were investigated. Compared with the average of world coals, the concentration of REY in the K1a coals were normal, dominated by light REY (LREY), with less medium and heavy REY (MREY, HREY). The fractionation degree of the MREY and HREY are higher than that of LREY in most K1a coal samples, deduced from the mixed enrichment type of REY, mainly including M-H-type, and a few L-M type and H-type. In addition, the combination of anomalies of Ce, Eu, Gd, and Al2O3/TiO2 parameters, the terrigenous materials in the K1a coal were derived from the felsic-intermediate rocks at the top of the Emeishan basalt sequence, and the samples were affected by seawater intrusion during early peat accumulation. Although the minerals primarily consist of kaolinite, illite, pyrite, and small amounts of quartz, calcite and anatase, REY are correlated with ash yield, SiO2, and Al2O3, revealing that the REY mainly occur in aluminosilicate minerals, especially kaolinite and illite. Meanwhile, REY positively relate to P2O5 and Zr, which may exist in phosphate-containing minerals or zircon. Furthermore, most samples in the K1a coal or ash do not reach the cut-off grade for the beneficial recovery of REY. With the exception of central Guizhou, southwestern Chongqing, and the junction of western Guizhou and northeastern Yunnan, the REY content in coals from southwestern China are high, and its by-products are suitable as potential REY sources. [ABSTRACT FROM AUTHOR]

The development of next-generation electronics requires scaling of channel material thickness down to the two-dimensional limit while maintaining ultralow contact resistance1,2. Transition-metal dichalcogenides can sustain transistor scaling to the end of roadmap, but despite a myriad of efforts, the device performance remains contact-limited3–12. In particular, the contact resistance has not surpassed that of covalently bonded metal–semiconductor junctions owing to the intrinsic van der Waals gap, and the best contact technologies are facing stability issues3,7. Here we push the electrical contact of monolayer molybdenum disulfide close to the quantum limit by hybridization of energy bands with semi-metallic antimony (01 1 ̅ 2 ) through strong van der Waals interactions. The contacts exhibit a low contact resistance of 42 ohm micrometres and excellent stability at 125 degrees Celsius. Owing to improved contacts, short-channel molybdenum disulfide transistors show current saturation under one-volt drain bias with an on-state current of 1.23 milliamperes per micrometre, an on/off ratio over 108 and an intrinsic delay of 74 femtoseconds. These performances outperformed equivalent silicon complementary metal–oxide–semiconductor technologies and satisfied the 2028 roadmap target. We further fabricate large-area device arrays and demonstrate low variability in contact resistance, threshold voltage, subthreshold swing, on/off ratio, on-state current and transconductance13. The excellent electrical performance, stability and variability make antimony (01 1 ̅ 2 ) a promising contact technology for transition-metal-dichalcogenide-based electronics beyond silicon.The electrical contact of two-dimensional transistors is pushed close to the quantum limit by hybridization of the energy bands with antimony; the contacts have low contact resistance and excellent stability. [ABSTRACT FROM AUTHOR]

The prevalence of per- and polyfluoroalkyl substances (PFASs) in agricultural soils has raised concerns regarding the health risks associated with the consumption of PFAS-contaminated agricultural products. The present study investigated the uptake and translocation of nine PFASs in lettuce using a hydroponic setting. During the uptake experiments, long-chain PFASs (≥ C8) exhibited greater accumulations in lettuce roots, while short-chain PFASs (≤ C7) manifested preferential transport to the shoots. The average root concentration factors of PFASs were positively correlated with their log Kow values. A significantly negative relationship was found between the average translocation factors of PFASs and their molecular volume. Sorption of long-chain PFASs by lettuce roots was enhanced after heating the roots to increase the cell membrane permeability. The accumulation of perfluorododecanoic acid increased significantly in shoots of lettuce plants without roots as compared to whole lettuce plants. Results of the present study indicate that sorption to root surface tissues and efficiency in passing through the root Casparian strip are two important factors that affect the uptake and distribution of PFASs within plants. [ABSTRACT FROM AUTHOR]

An anti-fouling aerogel with superior separation performance for separation of oil/water emulsion is of great significance to industrial development due to continuously increasing oily industrial wastewater. Herein, a superhydrophilic/underwater superoleophobic porous biobased aerogel with a three-dimensional network structure was prepared by the agricultural waste corn stalk (CS) incorporated with konjac glucomannan (KGM) through simple sol-gel and freeze-drying methods. The oil/water separation mechanisms and the effect of aerogel structural changes on the separation performance of CS/KGM aerogel for oil-in-water emulsions are discussed in detail. Using toluene as an oil phase, CS3.50K1.25 exhibited outstanding separation performance with an excellent separation efficiency above 96.26% and a high permeate flux above 2,381 L m−2 h−1 for oil-in-water emulsions. As expected, the separation efficiency and permeation flux can be wholly recovered after washing, indicating the aerogel possesses good sustainability. Moreover, CS/KGM aerogel has the advantages of low cost, simple preparation, eco-friendly and anti-fouling, revealing a promising candidate for the treatment of oily wastewater pollution. [ABSTRACT FROM AUTHOR]

Pile-fermentation is a critical procedure for producing Chinese dark tea, during which thermophilic microorganisms would play an irreplaceable role. However, there have been little researches on the influences of thermophilic microorganism pile-fermentation (TMPF) in high-temperature of Chinese dark tea. Thus, we conducted high-performance liquid chromatography and nontargeted metabolomic to analyze the non-volatile metabolites of TMPF. Our results discovered that the amounts of (−)-epigallocatechin gallate, (−)-epigallocatechin, (−)-epicatechin gallate, and (−)-epicatechin were decreased significantly (p < 0.05) after TMPF. By using nontargeted metabolomic analysis, a total of 1733 ion features were detected. KEGG pathway enrichment analysis showed that TMPF had a significant impact on caffeine metabolism. Also, theophylline, 3-methylxanthine, and 1,3,7-trimethyluric acid were increased significantly after TMPF, which suggested that demethylation and oxidation reaction might be the main pathways of caffeine metabolism. This study provides a better understanding of the mechanism of TMPF during high-temperature for Chinese dark tea and lays a foundation for further research. [ABSTRACT FROM AUTHOR]

Triazole pesticides are widely used for the control of pathogenic fungi in crops, which were frequently detected in edible parts. Its extensive use has caused many environmental pollution and food safety problems. In this study, the uptake, translocation, and subcellular distribution of three triazole pesticides (triadimefon, tebuconazole, and epoxiconazole) in rice were investigated. The results showed that the three triazole pesticides could be taken up by rice roots, but their distribution in plant tissues were different. The accumulation of the three pesticides in rice root followed the order of epoxiconazole (4.26 mg/kg, 24 h) > tebuconazole (2.63 mg/kg, 24 h) > triadimefon (1.37 mg/kg, 24 h), while a reversed order was observed in rice shoots, triadimefon (0.48 mg/kg, 24 h) > tebuconazole (0.40 mg/kg, 24 h) > epoxiconazole (0.21 mg/kg, 24 h). The translocation of triazole pesticides within rice tissues involved both symplast and apoplast pathways, with triadimefon preferentially through by the apoplast pathway and epoxiconazole through by the symplast pathway. The proportions of triadimefon, tebuconazole, and epoxiconazole in the symplast and apoplast of rice plants were 15–33%, 6–31%, 7–37%, and 67–85%, 69–94%, 63–93%, respectively. The subcellular distribution revealed that all pesticides have a higher proportion in cell walls than in cell organelles and soluble components. Epoxiconazole has the highest accumulated capacity in the cell wall (45–67%) and triadimefon was more concentrated in the soluble components (24–29%). However, there were no significant differences in the amount of three pesticides in cell organelles. The distribution of the three pesticides in aboveground and underground parts of rice plant, uptake and transportation in symplast and apoplast pathways, and distribution in the subcellular tissue are all related to their hydrophobicity. [ABSTRACT FROM AUTHOR]

Machine learning (ML) lifecycle is a cyclic process to build an efficient ML system. Though a lot of commercial and community (non-commercial) frameworks have been proposed to streamline the major stages in the ML lifecycle, they are normally overqualified and insufficient for an ML system in its nascent phase. Driven by real-world experience in building and maintaining ML systems, we find that it is more efficient to initialize the major stages of ML lifecycle first for trial and error, followed by the extension of specific stages to acclimatize towards more complex scenarios. For this, we introduce a simple yet flexible framework, MLife, for fast ML lifecycle initialization. This is built on the fact that data flow in MLife is in a closed loop driven by bad cases, especially those which impact ML model performance the most but also provide the most value for further ML model development—a key factor towards enabling enterprises to fast track their ML capabilities. Better yet, MLife is also flexible enough to be easily extensible to more complex scenarios for future maintenance. For this, we introduce two real-world use cases to demonstrate that MLife is particularly suitable for ML systems in their early phases. [ABSTRACT FROM AUTHOR]

This study investigated the influence of precipitation and temperature on the runoff and forest growth in the northern Greater Khingan Mountains of China through the hydrology, hydrochemistry and remote sensing methods. The rivers were found to be recharged not only by precipitation, but also by subpermafrost groundwater through water balance calculation and the relationships between precipitation, temperature and runoff. The stable isotope compositions of the river and groundwater more depleted than local precipitation indicating the great contribution of subpermafrost groundwater to runoff. Participation of subpermafrost groundwater makes the forest-permafrost water cycle in the northern Greater Khingan Mountains unique. [ABSTRACT FROM AUTHOR]

The Northern Junggar Basin experienced extensive subduction and a complex tectono-magmatic evolution during the Late Paleozoic, resulting in a heterogeneous distribution of volcanic rocks in the Junggar Basin. In this study, the Carboniferous tectono-magmatic evolution of the northern Luliang arc was described by exploring the petrography and geochemistry of Carboniferous volcanic rocks collected from well Y-2 and outcrop WW′ in the northern Luliang Uplift. The distribution, types, and formation ages of these volcanic rocks were characterized and the volcanic sequence in well Y-1 was divided into upper and lower parts according to vertical variations in selected geochemical data. Then the petrogenesis and tectonic settings of different volcanic rocks were evaluated and this was used to infer the tectono-magmatic evolution of the northern Luliang arc during the Carboniferous. The results indicate that: (1) Carboniferous high-K calc-alkali andesite–dacite associations are distributed in the west of the northern Luliang Uplift, and Lower Carboniferous calc-alkali basalt–dacite–rhyolite assemblages are preserved in its east. (2) The intermediate-acid volcanic rocks in wells Y-1 and Y-2 were derived from calc-alkali basaltic magma through melting of the juvenile lower crust, and geochemical variations indicate increasing addition of slab melting in a subduction-related arc environment. The bimodal volcanic rocks from outcrop WW′ were derived from lithospheric underplating of basaltic magma in an intra-arc extensional setting. (3) The closure of the eastern Keramaili Oceanic basin occurred before the Early Carboniferous, and the tectono-magmatic difference between the east and the west of the northern Luliang Uplift appeared before the Carboniferous period. [ABSTRACT FROM AUTHOR]

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Purpose: The addition of organic substrates can change the decomposition rate of soil organic matter (SOM), which is termed as "priming effect." The objective of this study was to explore the priming effects of SOM decomposition with the addition of different organic carbon substrates, including glucose, oxalic acid, and tannin. We hypothesized that with additions from labile to recalcitrant carbon substrates, the soil priming effects changed from positive to negative.Materials and methods: Representing from labile to recalcitrant carbon substrates, glucose, oxalic acid, and tannin were added to soil, respectively. Physicochemical properties of soil, carbon dioxide emission rate, soil organic carbon in the labile and recalcitrant carbon pools, microbial biomass carbon (MBC), and microbial community diversity and structure were measured in different treatments.Results and discussion: Results showed that the addition of glucose and tannin produced positive priming effects, while the addition of oxalic acid led to a negative priming effect. The addition of glucose and tannin significantly increased the MBC. The addition of glucose significantly promoted the carbon decomposition in both the labile and recalcitrant soil carbon pools. The addition of tannin greatly promoted carbon decomposition in the labile carbon pool and slightly decreased carbon decomposition in the recalcitrant carbon pool of the soil. However, the addition of oxalic acid reduced the MBC and resulted in insignificant changes of the different soil carbon pools. The addition of organic carbon substrates reduced the soil microbial community diversity, especially the addition of glucose. The different priming effects of the treatments with glucose and tannin were attributable to the different phases in the succession of SOM decomposition processes. The treatment with oxalic acid reduced the soil pH, resulting in inactive microbial growth and reproduction.Conclusions: The addition of both glucose (labile carbon) and tannin (recalcitrant carbon) produced positive priming effects. In contrast, the addition of oxalic acid produced a negative priming effect. Except the treatment with tannin, the hypothesis was successfully tested. The results from this study should be useful to better understand the turnover processes of soil carbon pools with exogenous carbon inputs. [ABSTRACT FROM AUTHOR]

Selection for probiotic candidates by in vivo experimental trials is time and labor consuming; more informed strategy is needed to select successful probiotic candidates. The aim of the study was to elucidate the microbial taxa transmitted from maize seeds to seedlings during the germination process of maize and their probiotic effects. The bacterial and fungal taxa in kernel germs and sprouts were analyzed by Illumina-based sequencing. The sprouts contained more diverse fungi than those in germs. The bacterial species (OTUs) declined with the germination from germs to the sprouts. However, the endophytic fungal diversity increased during the germination process. Seed-borne dominant bacterial genera Bacillus, Halomonas, and Shewanella and dominant fungal genera Aspergillus were also detected in sprouts. The spore-forming bacteria BS3 isolated directly from sprouts could promote growth of maize seedling and resistance to F. verticillioides under F. verticillioides-infested soils. The results suggested that maize contained core bacterial and fungal taxa during the development from seeds to sprouts, and the core endophytes showed more intimate correlation with host plants than did other microbial taxa. Illumina-based sequence analysis is feasible to guide probiotic candidate selection and isolation. [ABSTRACT FROM AUTHOR]

The aim of the present study is to investigate the effect of seed inoculation with endophytic denitrifiers on rice seedling growth and nitrogen use efficiency under low- and high-urea conditions. Pseudomonas sp. B2, Streptomyces sp. A9, and Fusarium sp. F3 were isolated from rice plant tissues. Rice seeds inoculated with the denitrifiers were sown in soil fertilized with 100 and 300 mg/kg urea concentrations, respectively. The denitrifiers increased soil ammonia concentrations or kept high ammonia concentration for a longer time in soils. However, soil nitrate concentrations with the denitrifier treatments were lower than that of the control. All the denitrifier treatments increased the chlorophyll content by more than 200% under the low urea condition. Compared to the control, the denitrifier inoculation treatments significantly increased shoot length, fresh weight, and dry weight of rice seedlings under the low- and high-urea conditions ( P < 0.05). The chlorophyll concentrations, shoot length, wet weight, and dry weight of all the denitrifier treatments under the low urea fertilization were significantly higher than those of the control under the high-urea fertilization ( P < 0.05). The nitrogen use efficiency of rice seedlings might be attributable to nitrate reductases of the denitrifiers, acting as the rice nitrate reductase. The treatment of endophytic denitrifiers significantly improved rice seedling growth and nitrogen use efficiency under both low- and high-urea conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of single and mixed culture of denitrifying fungi, bacteria, and actinobacteria on nitrogen removal and NO emission in treatment of wastewater. Denitrifying endophytes of Pseudomonas sp. B2, Streptomyces sp. A9, and Fusarium sp. F3 isolated from rice plants were utilized for treatment of synthetic wastewater containing nitrate and nitrite. Experiments were conducted under shaking and static conditions. Results showed that under the static condition, more than 97 % of nitrate removal efficiencies were reached in all the treatments containing B2. The nitrate removal rates within the first 12 h in the treatments of B2, B2+A9, B2+F3, and B2+A9+F3 were 7.3, 9.8, 11, and 11 mg L h, respectively. Under the shaking condition, 100 % of nitrite was removed in all the treatments containing B2. The presence of A9 and F3 with B2 increased the nitrite removal rates under both the shaking and static conditions. Compared to the B2 system, the mixed systems of B2+A9, B2+F3, and B2+A9+F3 reduced NO emission (78.4 vs. 19.4, 1.80, and 0.03 μM in 4 weeks, respectively). Our results suggested that B2 is an important strain that enhances nitrogen removal from wastewater. Mixed cultures of B2 with A9 and F3 can remove more nitrate and nitrite from wastewater and reduce nitrite accumulation and NO emission in the denitrification process. [ABSTRACT FROM AUTHOR]

Autophagy is a basic cellular process that decomposes damaged organelles and aberrant proteins. Dysregulation of autophagy is implicated in pathogenesis of neurodegenerative disorders, including Parkinson's disease (PD). Pharmacological compounds that stimulate autophagy can provide neuroprotection in models of PD. Nanoparticles have emerged as regulators of autophagy and have been tested in adjuvant therapy for diseases. In this present study, we explore the effects of quantum dots (QDs) that can induce autophagy in a cellular model of Parkinson's disease. CdTe/CdS/ZnS QDs protect differentiated rat pheochromocytoma PC12 cells from MPP-induced cell damage, including reduced viability, apoptosis and accumulation of α-Synuclein, a characteristic protein of PD. The protective function of QDs is autophagy-dependent. In addition, we investigate the interaction between quantum dots and autophagic pathways and identify beclin1 as an essential factor for QDs-induced autophagy. Our results reveal new promise of QDs in the theranostic of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Occurrence and distribution of eight selected endocrine-disrupting compounds (EDCs), including estrone (E1), 17α-ethinylestradiol (EE2), 17α-estradiol (αE2), 17β-estradiol (βE2), estriol (E3), bisphenol A (BPA), 4-nonylphenol (NP), and 4-octylphenol (OP), were investigated in surface water and sediments of the Three Gorges Reservoir region (TGRR). The mean concentrations of E1, αE2, βE2, E3, EE2, BPA, NP, and OP were 10.3, 3.3, 3.7, 17.2, 7.8, 26.6, 10.8, and 32.3 ng L respectively in surface water and 2.6, 4.1, 7.7, 2.4, 11.8, 17.4, 5.0, and 5.3 ng g dry weight (dw) respectively in sediments. BPA, NP, and OP were the main EDCs in both media. Distributions of EDCs in surface water and sediments varied significantly in space but not synchronously. The higher EDCs abundance was found in the upstream water of the TGRR. EDCs concentrations in sediments had no correlations with those in water and the total organic carbon content in sediments. EDCs presented low to high risks in the water, and steroidal estrogens were the main contributors to the total estrogenic activities. [ABSTRACT FROM AUTHOR]

The dietary uptake of Cd and Pb may contribute to the decline of migratory red-crowned cranes ( Grus japonensis) on the Asian mainland. To uncover the relevance of this hypothesis, we determined the concentrations of Pb and Cd as well as further macro and trace elements (Ca, Mg, Cu, Zn, Hg and As) in the gastric contents, gastric wall, intestinal wall, liver, kidney, muscle, and feathers of two individuals found dead in Zhalong Wetland in Northeastern China. Indeed, the Pb concentrations in the liver and kidney tissues was with 31.4 and 60.3 mg kg dry weight (dw), respectively, above concentrations considered as potentially toxic level in common birds (i.e. 30 mg kg). These Pb concentration may have possibly been associated with lethal toxicosis in this endangered species suggesting Pb as major threat for G. japonensis populations. Thus, the inputs of Pb into Zhalong Wetland should be reduced to maintain and reestablish environmental conditions supporting the population development of these migratory red-crowned cranes in the Zhalong Wetland, a critical crane habitat for the long-term sustainability of this species. [ABSTRACT FROM AUTHOR]

We established a model for investigating polycrystalline silicon (poly-Si) thin film transistors (TFTs). The effect of grain boundaries (GBs) on the transfer characteristics of TFT was analyzed by considering the number and the width of grain boundaries in the channel region, and the dominant transport mechanism of carrier across grain boundaries was subsequently determined. It is shown that the thermionic emission (TE) is dominant in the subthreshold operating region of TFT regardless of the number and the width of grain boundary. To a poly-Si TFT model with a 1 nm-width grain boundary, in the linear region, thermionic emission is similar to that of tunneling (TU), however, with increasing grain boundary width and number, tunneling becomes dominant. [ABSTRACT FROM AUTHOR]

Two cyanato-bridged dinuclear Mn(II) complexes [Mn(phen)( μ-NCO)][M(bpb)(CN)]·HO [M = Fe ( 1) or Co ( 2)], [phen = 1,10-phenanthroline, bpb = 1,2-bis(pyridine-2-carboxamido)benzenate] have been synthesized using the synthetic strategy of big anion inducement. Single-crystal X-ray diffraction analysis reveals that both complexes consist of a double end-on (EO) cyanato-bridged dinuclear Mn(II) unit and two free [M(bpb)(CN)] building blocks acting as counter-ions. Magnetic studies show the presence of abnormal antiferromagnetic interactions between the two Mn(II) centers through the EO cyanate bridge with J = −1.58(3) cm for complex 1 and −1.82(2) cm for complex 2. The unusual antiferromagnetic interactions of these complexes can be attributed to their small Mn(II)-N-Mn(II) angles. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) was considered as a critical growth factor for tumor expansion. The roles of VEGF121, VEGF165, and VEGF189 in tumor growth have been intensely investigated; however, involvements of another extracellular matrix (ECM)-binding VEGF isoform, namely VEGF183 (six amino acids shorter than VEGF189 in exon 6a), in physiological or pathological processes are still unclear although the wide tissue distribution. To investigate the role of VEGF183 in carcinogenesis, we generated murine breast cancer cell (EMT-6) clones stably overexpressing VEGF183, VEGF121, VEGF165, and VEGF189 shortened as V183, V121, V165, and V189, respectively. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) results showed that VEGF183, like all other VEGF-overexpressing isoforms except for VEGF121, could enhance the proliferation of mouse breast cancer EMT-6 cells. Immunochemistry results displayed that overexpressing VEGF183 and VEGF189 in EMT-6 cells induced larger proportional dilated microvessels. On the other hand, results from cell wound healing experiments demonstrated that all of the VEGF-overexpressing isoforms could increase the chemotaxis of EMT-6 cells in vitro. In conclusion, our results supported the idea that overexpression of VEGF183 promotes murine breast cancer cell proliferation in vitro and induces dilated intratumoral microvessels, and it plays a dissimilar role in comparison with that of VEGF189. [ABSTRACT FROM AUTHOR]

Five heavy metal concentrations, copper (Cu), zinc (Zn), lead (Pb), chromium (Cr), and cadmium (Cd), in the sediments and six typical aquatic animal taxa were analyzed to determine the contamination from heavy metals in the habitat of the red-crowned cranes in Northeastern China. The body burden of these metals in the cranes was analyzed to examine the impact of these hazards on the rare species. Results indicated that all detected concentrations of the five heavy metals in the sediments were higher than the natural background levels. Pb and Cd were the most abundant elements in the sediments, with concentrations ranging from 9.85 to 129.72 mg kg and from 1.23 to 10.63 mg kg (dry weight, dw), respectively. Their absolute fractions were relatively stable phases, i.e., bound to iron-manganese oxides fraction and bound to organic matter fraction at 16.28 and 23.23 mg kg for Pb and 0.33 mg kg and 3.15 mg kg (dw) for Cd. Six common water animal taxa were found to contain detectable heavy metal concentrations. The internal tissues of the red-crowned cranes contained significantly high metal concentrations compared with their external tissues (feather, feces and residual eggshell). Cd concentrations in the feather and liver of red-crowned cranes exceeded a level considered to be potentially toxic in birds, with levels ranging from 0.41 to 3.06 mg kg and 0.37 to 4.42 mg kg (dw), respectively. Similarly, we found increased levels of Pb in the both external and internal tissues, with levels ranging from 0.21 to 3.21 mg kg dw, which indicated likely contamination by the metal. [ABSTRACT FROM AUTHOR]

Laser flash photolysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) experiments were carried out to study the photosensitive damage induced by pazufloxacin (PAX) and the protection of lysozyme (Lyso) by ferulic acid (FCA), an active antioxidant. Transient absorption spectra revealed electron transfer from Lyso and FCA to PAX*, with respective bimolecular reaction rate constants of 6.3×10 and 1.4×10 dm/(mol s). A pulse radiolysis study was also performed to investigate the formation of Lyso radical cations. Results showed that FCA effectively inhibits the cross-linking of protein induced by fluoroquinolones. Finally, a mechanism of the protective effect of FCA on Lyso was proposed. [ABSTRACT FROM AUTHOR]

Purpose: The clinical outcome of chronic myeloid leukemia (CML) patients has been changed dramatically due to the development of imatinib (IM). However, the emergence of IM resistance, commonly associated with point mutations within the BCR-ABL kinase domain, remains a major clinical problem. Here, we investigated the effects of E35, a novel derivative of emodin, on the IM-resistant 32Dp210-T315I cells. Methods: Cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide and colony formation assay. Induction of apoptosis was confirmed by DNA fragmentation assay and annexin V/PI staining assay. Real-time quantitative PCR was used to access the BCR-ABL gene expression. Changes of related signaling molecules were detected through Western blot. Results: E35 was found to potently inhibit proliferation of 32Dp210-T315I cells with an average IC50 of 2.4 µM at 48 h. Colony formation was almost fully suppressed in 1.0 μM E35 group. DNA fragmentation and annexin V/PI staining assay exhibited the typical DNA fragmentation and the increased proportion of early apoptotic cells, respectively. The induction of apoptosis was associated with increase of Bax to Bcl-2 expression ratio and activation of caspase cascades involving decrease of pro-caspase 9 and pro-caspase 3 and increase of PARP cleavage. The protein expression of P210 and p-P210 was down-regulated in the presence of E35, although the mRNA levels remained almost unchanged. Moreover, the activation of the P210 downstream signaling pathways including CrkL, Akt/mTOR and MEK/ERK was fully suppressed by E35. Conclusion: Our study indicated that E35 might be a potential antileukemia agent against IM resistance in CML. [ABSTRACT FROM AUTHOR]

Heavy metal enrichment in the prey of red-crowned cranes in Zhalong Wetland, northeastern China was researched. Lead and Cd were the most abundant elements in the sediments; their concentrations ranged from 9.85 to 127 ppm and from 1.23 to 10.6 ppm, respectively. Six aquatic animal taxa contained detectable levels of heavy metals, in the decreasing order of Cyprinidae > Cobitidae > Dytiscidae > Odontobutidae > Viviparidae > Aeshnidae. Metal concentrations in these taxa followed the order: Zn > Cu > Cr > Pb > Hg > Cd. Metals in tissues of the red-crowned crane varied in the following order: Zn > Cr > Cu > Pb > Cd > Hg in feathers, and Zn > Cu > Hg > Cr > Pb > Cd in eggshells. Cadmium concentrations in the feathers of the red-crowned crane exceeded a level considered to be potentially toxic in birds (i.e., 0.22 ppm), ranging from 1.42 to 3.06 ppm. [ABSTRACT FROM AUTHOR]

Produced by bacteria, fungi and plants, siderophores are low-molecular-weight chelating agents (200-2,000 Da) to facilitate uptake of iron (Fe). They play an important role in extracellular Fe solubilization from minerals to make it available to microorganisms. Siderophores have various chemical structures and form a family of at least 500 different compounds. Some antibiotics (i.e., albomycins, ferrimycins, danomycins, salmycins, and tetracyclines) can bind Fe and some siderophores showed diverse biological activities. Functions and applications of siderophores derived from actinobacteria were reviewed to better understand the diverse metabolites. [ABSTRACT FROM AUTHOR]

Aflatoxins represent an important class of mycotoxins that are known to be mutagenic, carcinogenic, and teratogenic. Here, we report the use of the systematic evolution of ligands by exponential enrichment technology to screen for a DNA aptamer that recognizes Aflatoxin B1 (AFB1) with high affinity and specificity. AFB1 was first attached to magnetic nanoparticles and then incubated with an ssDNA library. After ten rounds of screening and amplification, 30 aptamer sequences were obtained following enrichment. Combined with a homological and structural analysis and affinity and specificity experiments, aptamer sequence 1, possessing the best affinity and specificity toward AFB1, was finally obtained. The dissociation constants value for aptamer sequence 1 was 11.39 nM. And, the specificity experiment results showed the binding between AFB1 aptamer with five other toxins was very week (did not exceed 15 % compared with AFB1). To demonstrate the potential use of this aptamer for quantitative analysis, a fluorescent bioassay with aptamer 1 was developed. The assay showed a wide linear range, with the AFB1 concentration ranging from 50 to 1,500 ng/L and a detection limit of 35 ng/L. Additionally, the spiked recovery experiment of AFB1 in peanut oil sample exhibited a recovery ratio between 94.2 and 101.2 % which showed good accuracy of the proposed aptamer-based bioassay. This fluorescent method represents a powerful tool for use in the detection of AFB1 without complex sample treatments. [ABSTRACT FROM AUTHOR]

The properties of norfloxacin (NFX) and its 4′-N-acetyl derivative (ANFX) are investigated in different pH aqueous solutions and HO-CHCN mixed solutions, to determine the effects of pH and polarity on their ground and excited states. The triplet states of NFX and ANFX are affected more by pH than by polarity. The pH dependence of the NFX and ANFX triplet states is likely due to the different quantum yields of different protonated forms. Steady-state fluorescence, time-resolved fluorescence, and laser flash photolysis experiments at different pH values provide clear evidence of the involvement of different intramolecular charge-transfer pathways in the singlet states of NFX and ANFX. The different electron-donating capacities of 1-N, 1′-N, and 4′-N under different conditions determine the major pathway. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the biosorption characteristics of Cd, Cu, and Pb by the fruiting body of jelly fungus Auricularia polytricha. Batch experiments were conducted to characterize the kinetics, equilibrium, and mechanisms of the biosorption process. Optimum values of pH 5, biomass dosage 4 g L, and contact time 60 min provided maximum biosorption capacities of A. polytricha for Cd, Cu, and Pb of 63.3, 73.7, and 221 mg g, respectively. The maximum desorption was achieved using 0.05 mol L HNO as an elute. The fruiting body was reusable at least for six cycles of operations. The pseudo-second-order model was the best to describe the biosorption processes among the three kinetic models tested. Freundlich and Dubinin-Radushkevich models fitted the equilibrium data well, indicating a heterogeneous biosorbent surface and the favorable chemisorption nature of the biosorption process. A Fourier transform infrared spectroscopy analysis indicated that carboxyl, amine/hydroxyl, amino, phosphoryl, and C-N-C were the main functional groups to affect the biosorption process. Synergistic ion exchange and surface complexation were the dominant mechanisms in the biosorption process. The present work revealed the potential of jelly fungus (fruiting body of A. polytricha) to remove toxic heavy metals from contaminated water. [ABSTRACT FROM AUTHOR]

A Cd-, Pb-, Zn-, Cu-resistant endophytic yeast CBSB78 was isolated from surface-sterilized rape roots. The isolate was identified as Cryptococcus sp. based on the ITS1-5.8S-ITS2 sequence analysis. The strain was resistant to 20 mM Cd, 20 mM Pb, 10 mM Zn, and 7 mM Cu. The yeast CBSB78 was a low indole-3-acetic acid (IAA) producer and possessed low 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Overall, 29.4-244 % of survival rates increased and the dry weight of Brassica alboglabra showed a 41.1 % increase when it was inoculated into the seedlings. The inoculation of CBSB78 could also increase the extraction amounts of Cd, Pb, and Zn by B. alboglabra simultaneously in the multi-metal contaminated soils, which showed the potential to improve extraction efficacy of Cd, Pb, Zn by B. alboglabra seedlings in the field. [ABSTRACT FROM AUTHOR]

The reactions between gatifloxacin (GFX) and various one-electron oxidants, such as OH, N, Br, and SO, have been studied by pulse radiolysis techniques. The GFX radical anion formed in the reaction of GFX with e could either be protonated or deprotonated, and the absorption of GFX radical anion was located at 390 nm. The transient species produced by the reaction of GFX with OH radical shows a broad band in the 380-600 nm region with a shoulder, while the oxidation by N, SO, and Br results in an absorption band with λ = 370 nm. At neutral condition (pH 7), the rate constants of GFX reacting with OH, N, Br, SO and e are estimated to be 1.0 × 10, 3.1 × 10, 2.8 × 10, 3.0 × 10, and 1.8 × 10 dm mol s, respectively. From the pH dependence on the formation of electron adducts and on the rate constant of GFX with e, the pK of GFX radical anion is estimated to be 5.5 and 9.3. [ABSTRACT FROM AUTHOR]

Photochemical processes of benzophenone (BP) and xanthone (XT) with tryptophan (TrpH) and tyrosine (TyrOH) were studied using the laser flash photolysis technique. It has been observed that the triplet state of BP and XT reacted with TrpH and TyrOH by hydrogen transfer with the formation of BP and XT ketyl radicals and oxidized radicals of Trp· and TyrO·. The related rate constants of these reactions were determined in this paper. The free energy changes (Δ G) of these reactions suggested that the proposed hydrogen transfer mechanism was thermodynamically feasible. These results provide theoretical foundation for further studying structural effects on the photochemical behaviors of proteins with triplet state BP and XT. [ABSTRACT FROM AUTHOR]

We collected eleven bench samples of No. 6 coal from the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China, and four samples from the affiliated coal preparation plant. Based on these samples, we used inductively coupled-plasma mass spectroscopy, X-ray diffraction, scanning electron microscope with an energy-dispersive X-ray spectrometer techniques, and borehole exploration data, to investigate the distribution, occurrence and enrichment causes of gallium (Ga) in the coals. Our results show: (1) Gallium is significantly enriched in the coal seams from the study area, with an average content of 18.8-26.0 ppm. Gallium is distributed heterogeneously in the coals, and reaches ore-forming scales only in No. 6 coal of Heidaigou Surface Mine, not in the other mining districts of Jungar Coalfield. (2) On the horizontal plane, Ga is enriched in the main minable coals from the northern and middle part of the coalfield. In the vertical profile, Ga content in the coal seams is higher at the base of Taiyuan Formation (Nos. 8 and 9) and Shanxi Formation (Nos. 3 and 4) than at the top of the Taiyuan Formation. Within the identical coal seam, Ga content is higher in the benches near the roof and floor than in the middle section. (3) Gallium in the coals is associated mainly with kaolinite and boehmite. Additionally, Ga may be adsorbed to some extent by humic acid, resulting in a high level in weathering coal. (4) Geological factors affect Ga enrichment in coal, such as the property of parent rocks in the source area, the sedimentary environment, organic matter, structure, and past magmatic hydrothermal activity. Especially, Ga content in parent rocks plays a leading role. (5) The mobility and precipitation of trace elements like Ga are controlled principally by the geochemical behavior of the major element Al. Terrestrial and transgressive environments can cause the precipitation of bauxite, whereas marine-continental depositional environments may cause the separation of Ga from Al. In addition, Ga may migrate in the form of gas, and may be affected by the ground temperature. Thus, it is relatively enriched in high-volatile coal. [ABSTRACT FROM AUTHOR]

Terahertz time-domain spectroscopy (THz-TDS) was employed to record the progress of the reaction between p-benzoquinone (BQ) and 4,4′-biphenol (4BP) in the solid state. Through the THz-TDS, distinct absorption peaks of reactants and products were obtained. Sample preparations in the solid state, with and without grinding, influenced the conversion kinetics. Several kinetic equations or models were tried to fit the reaction data. A kinetic rate constant was obtained, with the reaction observed to be consistent with diffusion-controlled mechanisms. Differential scanning calorimetry and X-ray powder diffraction analyses were also used to characterize the solid-state reaction and products. The study shows that THz spectroscopy is a promising tool in evaluating the complex formation through solid-state reactions. [ABSTRACT FROM AUTHOR]

Trichinella spiralis infection in rodents is a well-known model of intestinal inflammation associated with hypermotility. The aim of the study was to use this experimental model to elucidate if Th17 cells are involved in the development of gastrointestinal hypermotility. Colonic smooth muscle contractility was investigated in response to acetylcholine. The levels of IL-17, IL-23 and TGF-β1 in colon were measured by Western blotting. Flow cytometric detection of intracellular IFN-γ/IL-4/IL-17 cytokine production was used to analyze the proportions of CD4+ T cells subsets in colon. Our results showed that colonic muscle contractility was increased 2 weeks post infection (PI) and stayed high 12 weeks PI when no discernible inflammation was present in the gut. The proportion of Th17 cells and the expression of IL-17 were up-regulated in colon 2 weeks PI and returned to normal 8 weeks PI. The content of IL-17 was correlated with the colonic smooth muscle hypercontracility 2 weeks PI. Meanwhile, TGF-β1 was increased 2 weeks PI, while IL-23 was normal. Our results suggest that Th17 cells affect the colonic muscle contractility in mice infected with Trichinella spiralis at intestine stage but not at muscle stage and the effect of Th17 cells on muscle contractility might be induced by TGF-β1. Other cytokines might be involved in the hypercontracility of colonic smooth muscle at muscle stage. [ABSTRACT FROM AUTHOR]

Well resolved far-infrared spectra of 1,4-benzoquinone, 1,4-naphthoquinone, and 9, 10-anthraquinonme in polycrystalline form have been measured with terahertz time domain spectroscopy at room temperature. The characterizations of power absorption and index of refraction in the frequency range 0.3–2.0 THz are presented. Theoretical calculation is applied to assist the analysis and assignment of individual THz absorption spectra of the p-quinones with semiempirical AM1, Hartree-Fock (HF), and density functional theory (DFT) method. Observed THz responses are assigned to the translational and torsional vibrations of p-quinone dimer held together by weak hydrogen bonds. [ABSTRACT FROM AUTHOR]

Here we report transient spectral red-shift and transient absorption enhancement of p-benzoquinone radical in the presence of CdSe quantum dots after 355 nm pulse laser excitation. The spectral shift was caused by surface-bound p-benzoquinone molecules while the transient absorption increase was due to interfacial electron transfer from CdSe quantum dots to p-benzoquinone molecules. In contrast, spectral shift and absorption increase were much less significant for anthraquinone in the presence of CdSe quantum dots due to their weak adsorption abilities. [ABSTRACT FROM AUTHOR]

The photooxidation damage of lysozyme under 315–375 nm irradiation in the presence of riboflavin was studied by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Indications showed that the mechanisms and products of oxidative damage were relative to the concentration of riboflavin, the time of irradiation and the ambience. The type I process was examined in a nitrogen saturated solution, whereas both type I and type II were observed in an aerobic atmosphere and type II was the dominant process. The study also suggested that antioxidants, such as melatonin, can reduce the damage of lysozyme effectively. [ABSTRACT FROM AUTHOR]

The well-resolved absorption spectra of the hydroxycinnamic acid (HCA) derivatives, caffeic acid, ferulic acid, sinapic acid and chlorogenic acid, were measured over the frequency region from 0.3 to 2.0 THz at 294 K with terahertz time-domain spectroscopy (THz-TDS). Theoretical calculation was applied to assist the analysis and assignment of the individual THz absorption spectra of the HCA derivatives with density functional theory (DFT). The distinctive spectral features were originated from the collective motion of molecules held together by hydrogen bonds. The real and imaginary parts of dielectric function of the four HCA derivatives were also obtained. [ABSTRACT FROM AUTHOR]

The photo-physical and photo-chemical properties of melatonin (ML) were studied by 266 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radical cation of ML (ML•+) and hydrated electrons (e), while excited triplet state 3ML* is also formed during photolysis. The oxidation via one electron transfer from ML to SO4 •− and the triplet state of riboflavin (3RF*) has been also investigated and the rate constants for the process have been determined to be 8.0×109 and 1.4×109 L·mol−1·s−1 respectively. The radical cation of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS•+) scavenging capacities of melatonin and other antioxidants are compared in this paper. [ABSTRACT FROM AUTHOR]

The well-resolved absorption spectra of D-xylose, D-ribose, D-arabinose, D-lyxose and other related substances in the spectral region between 0.3 and 2.0 THz are measured using terahertz time-domain spectroscopy (THz-TDS) at 295 K. Comparing the absorption spectra of different chemicals, we can distinguish the samples easily. Thus THz-TDS is demonstrated to be a power and characteristic spectral tool, which is highly sensitive to the minor changes of the molecular structures and can be applied to detect and analyze similar materials. [ABSTRACT FROM AUTHOR]

Based on the analyses of sulfur and 41 other elements in 8 channel samples of the No. 11 coal seam from Antaibao surface mine, Shanxi, China and 4 samples from the coal preparation plant of this mine, the distribution of the elements in the seam profile, their geochemical partitioning behavior during the coal cleaning and the genetic relationships between the both are studied. The conclusions are drawn as follows. The coal-forming environment was probably invaded by sea water during the post-stage of peatification, which results in the fact that the contents of As, Fe, S, etc. associated closely with sea water tend to increase toward the top of the seam, and that the kaolinite changes into illite and montmorillonite in the coal-sublayer near the roof. These elements studied are dominantly associated with kaolinite, pyrite, illite, montmorillonite, etc., of which the As, Pb, Mn, Cs, Co, Ni, etc. are mainly associated with sulfides, the Mo, V, Nb, Hf, REEs, Ta etc. mainly with kaolintie, the Mg, Al etc. mainly with epigenetic montmorillonite, and the Rb, Cr, Ba, Cu, K, Hg, etc. mainly with epigenetic illite. The physical coal cleaning is not only effective in the removal of ash and sulfur, but also in reducing the concentration of most major and trace elements. The elements Be, U, Sb, W, Br, Se, P, etc. are largely or partly organically bound showing a relatively low removability, while the removability of the other elements studied is more than 20%, of which the Mg, Mn, Hg, Fe, As, K, Al, Cs, and Cr associated mostly with the coarser or epigenetic minerals show a higher removability than that of ash. The distribution of the elements in the seam profile controls their partitioning behavior to a great degree during the coal cleaning processes. [ABSTRACT FROM AUTHOR]