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Abstract: Diffusion tensor imaging requires correction of eddy current distortion in diffusion-weighted images. An effective retrospective correction approach is to transform a diffusion-weighted image to maximize the mutual information (MI) between the transformed diffusion-weighted image and the corresponding T2-weighted image. In the literature, either linear interpolation or partial volume interpolation is applied to estimate the MI objective function. However, these interpolation methods induce artifacts to the MI objective function, thus compromising correction results. In this work, the MI objective function is estimated based on interpolation using Fourier shift theorem. This method eliminates the artifacts incurred with the aforementioned interpolation methods. The algorithm is further improved by approximating pixel values using their nearest neighbors in the up-sampled spatial domain, resulting in dramatically increased computational efficiency without compromising the correction results. The effects of varying the number of quantization levels and using Parzen window filtering to smooth the MI objective function are also investigated to obtain optimized algorithm parameters. The diffusion tensor image quality after applying the proposed distortion correction method is significantly improved visually. [Copyright &y& Elsevier]

Highlights • A deoxynivalenol-degrading bacterium was identified as Devosia insulae A16. • D. insulae A16 was able to eliminate 84.7% of DON at 20 mg/L within 24 h. • The degradation product were determined to be 3-keto-deoxynivalenol. • A16 is also able to degrade 3-acetyl- and 15-acetyl-deoxynivalenol. Abstract Deoxynivalenol (DON), a notorious mycotoxin mainly found in Fusarium -contaminated crops, causes great loss in livestock farming and severe safety risks to human health. Here we report the isolation of a Gram-negative bacterial strain with effective biodegrading abilities on DON and its derivatives including 3-acetyl-DON and 15-acetyl-DON. The strain was identified as Devosia insulae A16 on the basis of morphological and physiological characteristics and 16S rRNA-based phylogenetic analysis. D. insulae A16 was able to degrade 88% of 20 mg/l DON within 48 h under aerobic conditions at 35 °C and neutral pH. The major degradation product of DON and its derivatives was 3-keto-DON by the oxidation of the hydroxyl group at C-3. Both 3-acetyl-DON and 15-acetyl-DON underwent a deacetylation reaction to generate DON prior to the degradation to 3-keto-DON. The results provide the potential use of D. insulae A16 as a biodegradation agent to control DON contamination in cereals. [ABSTRACT FROM AUTHOR]

Indoleamine 2,3-dioxygenase (Ido) is a tryptophan-degrading enzyme that is widely distributed across species. Ido catalyzes the first step of tryptophan (TRP) degradation and drives the de novo synthesis of nicotinamide adenine dinucleotide (NAD+) coenzymes via the kynurenine (KYN) pathway. The budding yeast Saccharomyces cerevisiae possesses a single IDO gene (BNA2) that is responsible for NAD+ synthesis, whereas a number of fungal species contain multiple IDO genes. However, the biological roles of IDO paralogs in plant pathogens remain unclear. In the current study, we identified three FgIDOs from the wheat head blight fungus Fusarium graminearum. FgIDOA/B/C expression was significantly induced upon TRP treatment. Targeted disruption of FgIDOA and/or FgIDOB caused different levels of NAD+ auxotrophy, thus resulting in pleotropic phenotypic defects. Loss of FgIDOA resulted in abnormal conidial morphology, reduced mycelial growth, decreased virulence in wheat heads and reduced deoxynivalenol accumulation. Exogenous addition of KYN or various intermediates involved in the KYN pathway rescued auxotrophy of the mutants. Metabolomics analysis revealed shifts toward alternative TRP degradation pathways to melatonin and indole derivatives in mutants lacking FgIDOB. Upregulation of partner genes in auxotrophic mutants and the capacity to rescue the auxotroph by overexpressing a partner gene indicated functional complementation among FgIDOA/B/C. Taken together, the results of this study provide insights into differential roles in paralogous FgIDOs and how fungal TRP catabolism modulates fungal development and virulence. [ABSTRACT FROM AUTHOR]

[Display omitted] Age-related hearing loss (ARHL) is a most widespread neurodegenerative disease affecting the elderly population, but effective pharmacological treatments remain limited. Curcumin is a bioactive compound of Curcuma longa with antioxidant properties. Herein, we looked into the effects of curcumin on the H 2 O 2 -induced oxidative stress in cochlear hair cells and hearing function in an ARHL animal model (C57BL/6J mice). We found that pretreatment of curcumin could attenuate H 2 O 2 -induced apoptosis and cell senescence in auditory hair cells and prevent mitochondrial function dysfunction. More specifically, Western blot and luciferase activity assay showed that curcumin activated the nuclear translocation of Nrf2, which in turn triggered the activation of its downstream target gene Heme Oxygenase1 (HO-1). The enhanced Nrf2 and HO-1 activity by curcumin was blocked by the AKT inhibitor LY294002, indicating the protective effect of curcumin was mainly achieved by activating Nrf2/HO-1 through the AKT pathway. Furthermore, the knockdown of Nrf2 with siRNA diminished the protective effects of Nrf2 against apoptosis and senescence, consolidating the pivotal role of Nrf2 in the protective effect of curcumin on auditory hair cells. More importantly, curcumin (10 mg/kg/d) could attenuate progressive hearing loss in C57BL/6J mice, as evident from the reduced threshold of auditory nerve brainstem response. Administration of curcumin also elevated the expression of Nrf2 and reduced the expression of cleaved-caspase-3, p21, and γ-H2AX in cochlear. This study is the first to demonstrate that curcumin can prevent oxidative stress-induced auditory hair cell degeneration through Nrf2 activation, highlighting its potential therapeutic value in preventing ARHL. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEN), mainly produced by Fusarium species, is an estrogenic mycotoxin which causes reproductive disorders in livestock. In this study, we described a simple and rapid method for screening of ZEN-degrading bacteria by esterase activity assay. Soil bacteria strains were first tested for their esterase activities, then active strains were further evaluated for their ZEN-degrading potentials. A bacterial strain named Bacillus pumilus ES-21 was detected to be able to eliminate ZEN in the culture medium. ZEN degradation conditions were optimized through response surface methodology and the result showed that the degradation rate of ZEN by Bacillus pumilus ES-21 was up to 95.7% at the ZEN concentration of 17.9 μg/ml within 24 h. One of the degradation product was proposed to be 1-(3,5-dihydroxyphenyl)-6′-hydroxy-l′-undecen-l0′-one according to LC-TOF-MS/MS analysis. This study provided a strategy for the isolation of ZEN degrading microbes and a promising degrading strain. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEN) is a mycotoxin produced mainly by various Fusarium species which occur naturally in many crops worldwide. ZEN causes reproductive disorders and hyperestrogenic syndromes in animals and humans. This study aimed to isolate ZEN-degrading bacteria to develop strategies for detoxifying ZEN contamination in cereal crops. We screened approximately 1000 colonies for degrading ability and found four strains were capable of degrading ZEN. We selected one strain ZDS-1 for further study because it showed the high ZEN-degrading ability. On the basis of morphological, physiological and phylogenetic analysis of its 16SrRNA, gyr A gene sequences, strain ZDS-1 was identified as Bacillus amyloliquefaciens . The optimal conditions for the biodegradation of ZEN by ZDS-1 were temperature; 30 °C, pH; 6.0–7.0, and cell concentration; 5 × 10 8 cfu/mL. ZDS-1 could degrade ZEN efficiently with the concentration from 1 mg/L to 100 mg/L. ZDS-1 not only could remove ZEN in the culture medium, but also could degrade ZEN in wheat. The ZEN removal by ZDS-1 was not due to binding or absorption, and during the process of ZEN degradation, no ZEN derivatives of ZEN were produced. These results suggested that Bacillus amyloliquefaciens ZDS-1 would be explored further for its ability to degrade ZEN in field trials. [ABSTRACT FROM AUTHOR]

The present study was performed to identify prevailing Fusarium species and the environmental factors affecting their frequencies and the contamination of grain with major mycotoxins in Jiangsu province. The precipitation levels were 184.2 mm, 156.4 mm, and 245.8 mm in the years 2013–2015, respectively, and the temperature fluctuated by an average of 10.6 ± 7.2 °C in 2013, 10.9 ± 7.2 °C in 2014, and 10.6 ± 6.3 °C in 2015. Co-occurrence of deoxynivalenol (DON), 3-acetyldeoxynivalenol (3ADON), and 15-acetyldeoxynivalenol (15ADON) were observed in wheat. The average concentrations of DON were 879.3 ± 1127.8, 627.8 ± 640.5, and 1628.6 ± 2,168.0 μg/kg in 2013–2015, respectively. The average concentrations of 3ADON were 43.5 ± 59.0, 71.2 ± 102.5, and 33.5 ± 111.9 μg/kg in 2013–2015, respectively. We found that the average concentration of DON in wheat was positively correlated with precipitation ( r = 0.998, p < 0.01), and 3ADON was negatively correlated with precipitation ( r = − 0.887, p < 0.05). However, there was no correlation between precipitation and 15ADON or nivalenol (NIV). The differences in temperature were not as significant as the differences in rainfall amount over a short time period. Therefore, there were no correlations between temperature and the concentrations of trichothecenes, excluding 3ADON ( r = 0.996, p < 0.01). Our data indicated that Fusarium asiaticum is the primary pathogenic fungus prevalent in the Fusarium head blight disease nursery. The trichothecene chemotype composition differed between Fusarium graminearum sensu stricto (s. str.) and F. asiaticum isolates. The 3ADON chemotype was found only among strains of F. asiaticum . The NIV chemotype was not observed among strains of F. graminearum , while the 15ADON chemotype represented 100% of the F. graminearum strains collected. The results of this study indicated no correlations between environmental conditions and the species or genetic chemotype composition of pathogens in Jiangsu province in 2013–2015. [ABSTRACT FROM AUTHOR]

Meta-sedimentary rocks are widely distributed within the Diancang Shan–Ailao Shan metamorphic complex in the Southeastern Tibetan Plateau. Detailed geochemical analyses show that all of them have similar geochemical features. They are enriched in light rare-earth elements (LREEs) and depleted in heavy rare-earth elements (HREEs), with moderately negative Eu anomalies (Eu/Eu ∗ = 0.55–0.75). Major and trace element compositions for the meta-sedimentary rocks suggest that the protoliths were probably claystone, siltstone, and greywacke and deposited in an active continental margin. Garnet porphyroblasts in meta-sedimentary rocks have distinct compositional zonation from core to rim. The zonation of garnet in St–Ky–Grt–Bt–Ms schist indicates an increasing P – T trend during garnet growth. In contrast, garnets from (Sil)–Grt–Bt paragneiss show diffusion zoning, implying a decreasing P – T trend. Based on mineral transformations and P – T estimates using conventional geothermobarometers and pseudosection calculations, four metamorphic stages have been determined, including an early prograde metamorphic stage (M 1 ), a peak amphibolite–granulite facies metamorphic stage (M 2 ), a near-isothermal decompression stage (M 3 ), and a late amphibolites-facies retrograde stage (M 4 ). The relic assemblage of Ms + St ± Ky ± Bt ± Kfs + Qz preserved as inclusions in garnet porphyroblasts of the meta-sedimentary rocks belongs to prograde (M 1 ) stage and records P – T conditions of 560–590 °C and 5.5–6.3 kb. Matrix mineral assemblages of Grt + Bt + Ky/Sil + Pl + Qz and Grt + Bt ± Sil + Pl ± Kfs + Qz formed at peak (M 2 ) stage yield P – T conditions of 720–760 °C and 8.0–9.3 kb. M 3 is characterized by decompression reactions, dehydration melting of assemblages that include hydrous minerals (e.g., biotite), and partial melting of felsic minerals. The retrograde assemblages is Grt + Bt + Sil + Pl + Qz formed at 650–760 °C and 5.0–7.3 kb. At the amphibolites-facies retrograde (M 4 ) stage, fine-grained biotite–muscovite-bearing symplectites were formed, which occur at the grain boundaries of garnet and felsic minerals; such assemblage as Bt + Ms + Pl ± Kfs ± Grt + Qz were formed at 553–613 °C and 4.0–5.0 kb. The metamorphic history of the Diancang Shan–Ailao Shan metamorphic complex is thus defined by a clockwise P – T trajectory which includes a nearly isothermal decompression recording the subduction, collision and exhumation events between the Yangtze and Indochina blocks at Oligocene to Early Miocene, prior to the regional strong left-lateral shearing along the Ailao Shan-Red River Fault. [ABSTRACT FROM AUTHOR]

• Smartphone-controlled NIR spectrometer was successfully used to detect FBs contamination in corn. • The spectral absorbance intensity of corn samples varied with the different levels of FBs contamination. • LPLS-S showed higher prediction accuracy of FBs content in corn than PLS and SVM models. • PLS-DA and SVM-DA showed similar results for classifying corn samples according to the MRL of FBs. A portable near-infrared (NIR) spectrometer coupled with chemometrics for the detection of fumonisin B 1 and B 2 (FBs) in ground corn samples was proposed in the present work. A total of 173 corn samples were collected, and their FB contents were determined by HPLC–MS/MS. Partial least squares (PLS), support vector machine (SVM) and local PLS based on global PLS score (LPLS-S) algorithms were employed to construct quantitative models. The performance of the SVM and LPLS-S was better than that of PLS, and the LPLS-S presented the lowest RMSEP (12.08 mg/kg) and the highest RPD (3.44). Partial least squares-discriminant analysis (PLS-DA) and support vector machine-discriminant analysis (SVM-DA) were used to classify corn samples according to the maximum residue limit (MRL) of FBs, and the discriminant accuracy of both the PLS-DA and SVM-DA algorithms was above 86.0%. Thus, the present study provided a rapid method for monitoring FB contamination in corn samples. [ABSTRACT FROM AUTHOR]

The precise constraints on the timing of metamorphism of the Changhai metamorphic complex is of great importance considering the prolonged controversial issue of the north margin and the extension of the Sulu–Dabie HP–UHP Belt. While the monazite U–Th–Pb and muscovite 40 Ar/ 39 Ar techniques are widely accepted as two of the most powerful dating tools for revealing the thermal histories of medium–low grade metamorphic rocks and precisely constraining the timing of metamorphism. The Changhai metamorphic complex at the SE Jiao–Liao–Ji Belt, North China Craton consists of a variety of pelitic schist and Grt–Ky-bearing paragneiss, and minor quartzite and marble. Analyses of mineral inclusions and back-scattered electric (BSE) images of monazites, combined with LA–ICP–MS U–Th–Pb ages for monazites and 40 Ar/ 39 Ar ages for muscovites, provide evidence of the origin and metamorphic age of the Changhai metamorphic complex. Monazites separates from various Grt–Mus schists and Grt–Ky–St–Mus paragneisses exhibit homogeneous BSE images from cores to rims, and contain inclusion assemblages of Grt + Mus + Qtz ± Ctd ± Ky in schist, and Grt + Ky + St + Mus + Pl + Kfs + Qtz inclusions in paragneiss. These inclusion assemblages are very similar to matrix minerals of host rocks, indicating they are metamorphic rather than inherited or detrital in origin. LA–ICP–MS U–Th–Pb dating reveals that monazites of schist and paragneiss have consistent 206 Pb/ 238 U ages ranging from 228.1 ± 3.8 to 218.2 ± 3.7 Ma. In contrast, muscovites from various schists show slightly older 40 Ar/ 39 Ar plateau ages of 236.1 ± 1.5 to 230.2 ± 1.2 Ma. These geochronological and petrological data conclude that the pelitic sediments have experienced a metamorphic event at the Mid–Late Triassic (236.1–218.2 Ma) rather than the Paleoproterozoic (1950–1850 Ma), commonly regarded as the Precambrian basement for the Jiao–Liao–Ji Belt. Hence, the Changhai metamorphic complex should be considered as a discrete lithotectonic group. This newly recognized Mid–Late Triassic metamorphic event (236.1–218.2 Ma) for the Changhai metamorphic complex is coeval with the HP–UHP metamorphic event (235–220 Ma) for Sulu–Dabie rocks. This leads us to speculate that the metamorphism of the Changhai complex belt along the SE margin of the North China Craton was genetically related to the Mid–Late Triassic collision of the North China and South China cratons. By the same token, the Sulu–Dabie HP–UHP Belt may have extended through Yantai, and the southern Yellow Sea, and to the southern side of the Changhai metamorphic complex. [ABSTRACT FROM AUTHOR]

Highlights: [•] A three-year survey was conducted to evaluate the natural occurrence of DON and ZEN in FHB frequently epidemic region. [•] 74.4% Wheat samples were DON contaminated, while 12.8% of them were ZEN contaminated. [•] Rainfall from flowering to harvesting plays a major role in DON and ZEN accumulation. [Copyright &y& Elsevier]

The present study aimed to evaluate the feasibility of using near-infrared hyperspectral imaging (NIR-HSI) and chemometrics for quantifying deoxynivalenol (DON) in individual wheat kernels. In total, 120 wheat kernels of severely damaged kernels, moderately damaged kernels and asymptomatic kernels (SDKs, MDKs and AKs, respectively) were collected, and the DON content in the individual wheat kernels was analyzed by HPLC-MS/MS. Partial least squares (PLS), support vector machine (SVM) and local PLS based on global PLS scores (LPLS-S) algorithms were employed for building quantification models of DON. The results showed that SDKs and MDKs might contain low or no DON, while AKs could have a high DON content. Comparing the three modeling strategies, LPLS-S using mixed spectra achieved the best performance for kernels with RMSEP of 40.25 mg/kg and RPD of 2.24, which confirmed that NIR-HSI could be a feasible method for monitoring DON in individual kernels and removing highly contaminated kernels prior to food chain entry. • The impact of the kernel orientation (crease facing down or up) on the model results was investigated. • Wheat kernels were classified according to the degree of Fusarium infection by NIR-HSI and PLS-DA. • NIR-HSI combined with chemometrics was employed to quantify DON content in individual kernels. [ABSTRACT FROM AUTHOR]

Fusarium graminearum is the predominant pathogen related to Fusarium head blight (FHB) which causes mycotoxin contamination of grains, mainly involving zearalenone (ZEN) and deoxynivalenol. The present work aimed to isolate a bacterium capable of antagonizing various phytopathogenic fungi and degrading ZEN effectively. Through co-culture with Fusarium graminearum , the bacterial strain MQ01 was isolated from wheat rhizosphere soil for its antifungal activity and identified as Bacillus amyloliquefaciens according to its morphological, physiological and biochemical characteristics and phylogenetic trees based on sequences of the 16 S rRNA and gyr B genes. B. amyloliquefaciens MQ01 showed broad-spectrum antifungal activity against eight phytopathogens, namely F. oxysporum , Sclerotinia sclerotiorum , F. proliferatum , F. verticillioides , Colletotrichum gloeosporioides , Microdochium nivale , F. equiseti and F. semitectum. The antifungal substances were extracted, separated by native-PAGE and identified through MALDI-TOF-MS. Protein homology analysis showed that the two antagonistic components were chitin-binding protein and subtilisin, respectively. In addition, MQ01 showed a prominent degradation capacity of ZEN both in liquid medium (94.1%) and in practical samples such as corn (27.9%) and distiller's dried grains with solubles (35.3%). One of the degradation product was identified as 1-(3,5-dihydroxyphenyl)-6′-hydroxy-l'-undecen-l0′-one by TOF-MS/MS analysis. In conclusion, B. amyloliquefaciens MQ01 shows promising prospects for use as a biocontrol agent against FHB and for ZEN degradation under field conditions. • An antagonistic bacterial strain against Fusarium graminearum was isolated and identified as Bacillus amyloliquefaciens MQ01. • The inhibitory rates of MQ01 against eight phytopathogenic fungi ranged from 17.4% to 57.3%. • The antifungal substances were separated and identified as chitin-binding protein and subtilisin by MALDI-TOF-MS. • Bacillus amyloliquefaciens MQ01 was able to eliminate zearalenone to an extent of 27.9% in corn and 35.3% in DDGS. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), caused by the fungal pathogen Fusarium graminearum , is a destructive and widespread wheat disease. Chemical fungicides are becoming less effective at reducing the disease severity of FHB, and there is a need to find a more effective, low-cost natural product. A by-product of the pyrolysis of wheat straw is a condensate known as wheat straw vinegar, which was hypothesized to be an effective F. graminearum inhibitor in wheat. The organic and mineral compositions of wheat straw vinegar were analyzed. The results of GC–MS indicated that the major organic compounds in wheat straw vinegar are phenolics and acetic acid. The main inorganic elements in the liquid were K, Ca, S and Mg. A bio-test of wheat straw vinegar showed strong antifungal activity on F. graminearum growth and production of deoxynivalenol (DON) with an EC 50 (concentration for 50% of maximal effect) value of 3.1 μl ml−1. Field tests showed that the application of wheat straw vinegar diluted 200-fold significantly decreased the wheat FHB infection rate and DON content by 66% and 69%, respectively. The control efficacy of wheat straw vinegar at a dilution of 200-fold was similar to that of typical chemical fungicide applications. The use of wheat straw vinegar may increase farmers' income by reducing the net fungicide costs. Therefore, wheat straw vinegar has high potential as a natural fungicide for the control of FHB and can reduce the dependence on synthetic fungicides. Unlabelled Image • Wheat straw vinegar inhibited F. graminearum growth and deoxynivalenol production. • Wheat straw vinegar has a high potential as natural fungicide to the control of FHB • Using of wheat straw vinegar increase farmers' income by reducing the fungicide cost. • Recycling wheat straw vinegar may benefit the pyrolysis industry in China. [ABSTRACT FROM AUTHOR]

• The highly water-dispersible magnetic material MNPs/β-CDP was well prepared. • A water treatment model integrating adsorption and oxidation was established. • The MNPs/β-CDP exhibited remarkable kinetics, adsorption capacity and reusability. • This method could reduce secondary pollution and achieve non-polluting degradation. • The recovered material could be directly reused without any elution operation. Here, a porous superparamagnetic composite material magnetic β-cyclodextrin polymer (MNPs/β-CDP) was prepared and characterized as a adsorbent that may be used for the degradaion of acetaminophen (APAP) in aqueous solution by coupling with potassium permanganate (KMnO 4) oxidation. The results of adsorption properties investigation showed that the adsorption rate and capacity of MNPs/β-CDP were better than the component materials. When coupled with KMnO 4 oxidation, the degradation efficiency were evaluated with regards to the pseudo-first-order kinetics of 4-CP degradation. As an oxidation reactor, the material effectively alleviated the secondary pollution and water coloration caused by oxidation of KMnO 4. Moreover, the materials were directly regenerated by the reaction of KMnO 4 with APAP adsorbed in its cavities without additional elution treatment, making it more convenient and environmentally friendly. The repeated degradation experiments demonstrated that MNPs/β-CDP had mechanic stability and reusability. The findings provide novel ideas for the degradation of persistent contaminants in water environments. [ABSTRACT FROM AUTHOR]