Postharvest rot caused by fusarium species is considered one of the most devastating diseases limiting production and commercialization of water melon worldwide. Two economically important fungi species are generally ...
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Postharvest rot caused by fusarium species is considered one of the most devastating diseases limiting production and commercialization of water melon worldwide. Two economically important fungi species are generally responsible for fruit rot in watermelon. The aim of this study was to identify and characterize the fruit rot causing pathogen in watermelon in Ibadan Nigeria. Symptomatic watermelon leaves and fruits expressing severe wilt and rot were collected and cultured on solidified Potato dextrose agar. Pure culture of the isolated pathogen was identified based on morphological and molecular characterization as a new species offusarium viz. fusarium chlamydosporium. The pathogenicity off. chlamydosporum confirmed on watermelon and golden melon fruits revealed its capability to cause infection on healthy fruits. Golden melon fruits artificially inoculated with f. chlamydosporum isolate had higher rot diameter (81.7 mm) than watermelon (40.0 mm), disease incidence and severity also was significantly higher in golden melon with 88.3% and 100.0% respectively. To our knowledge this is the first report off. chlamydosporum as a causal pathogen of watermelon wilt and fruit rot disease in Nigeria.
Robust Independent Modelling of Class Analogy (RSIMCA) was applied to classify over 2,800 Passaic River sediment samples into seven groups or not assigned to any group after an initial screening of a 3,255 sample data...
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Robust Independent Modelling of Class Analogy (RSIMCA) was applied to classify over 2,800 Passaic River sediment samples into seven groups or not assigned to any group after an initial screening of a 3,255 sample dataset. This multivariate statistical output was compressed from seven latent dimensions into two interpretable dimensions using t-Distributed Stochastic Neighbor Embedding (t-SNE) graphics. Polytopic Vector Analysis (PVA) was then used to identify distinct source end-members based on PCDD/f characteristics of the classified samples. Among several advantages, the integrated chemometrics approach 1) applies emerging data visualization tools in this "Big Data" era to retain the fidelity of high-dimensional data attributes of a chemical dataset spanning over two decades of sample collection;2) employs a classification technique undisturbed by compositional outliers yet tracks those for subsequent investigations;3) provides an intuitive reduced-dimensional data visualization map for the PVA mixing polytope solution;4) fills a data gap in the contextual inventory of PCDD/f source dynamics in a complex river system;and 5) serves as a backdrop for further forensics investigations of the finer structure of less dominant point sources and potential upland source end-members in sediments. This tiered chemometrics strategy provides a strong weight-of-evidence approach to the interpretation of sediment data.
This study is the first attempt to document methodology development undergone using liquid chromatography tandem quadrupole time offlight mass spectrometry (LC-QTOf) to investigate degradation products of eutectic bi...
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This study is the first attempt to document methodology development undergone using liquid chromatography tandem quadrupole time offlight mass spectrometry (LC-QTOf) to investigate degradation products of eutectic bis(2,2-dinitropropyl) acetal/formal nitroplasticizer (called NP here). Method properties investigated are: desolvation temperature (degrees C) and spray voltage (V) of the electrospray ionization source, and the development of an acetone system rinse to prevent any residual contamination between sample injections. Details are given on why it is essential to investigate method optimization with changes shown in MS/MS analysis in addition to MS results. Trends in MS/MS analytic results reveal important relationships between baseline and aged materials. In addition to verification of previously proposed fragments, insights offered by this newly developed methodology will also identify new degradation products and shed light on the complexity of NP degradation chemistry.
A series of Mn1-xNi1-xfe2xSi0.95Al0.05 MM'X-type compounds (with x = 0.28, 0.3, 0.32 and 0.35) were investi-gated for their potential as magnetocaloric materials. Structural and magnetic properties were studied by...
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A series of Mn1-xNi1-xfe2xSi0.95Al0.05 MM'X-type compounds (with x = 0.28, 0.3, 0.32 and 0.35) were investi-gated for their potential as magnetocaloric materials. Structural and magnetic properties were studied by magnetometry, microscopy and X-ray diffraction. Double substitution offe in Mn and Ni sites allowed to tune martensitic transition temperatures between low temperature orthorhombic and high temperature hexagonal structures from 373 K in x = 0.28-183 K in x = 0.35 during cooling. Transition temperatures occur around room temperature for x = 0.30 (300 K for cooling transformation) and 0.32 (270 for heating transformation). Isothermal entropy changes of-8,-19 and-26 J/kg.K were calculated for field changes of mu 0H = 0-2, 0-5 and 0-7 T for x = 0.30. The values are comparable to those reported for MnNi(SiAl)-based compounds with single site substitutions (Mn and Ni) by fe. further analyses show that high magnetic fields are necessary to induce the magnetostructural transition in all studied compounds, which can be attributed to the presence of secondary phases and/or disorder at a local level.
Chestnut rose, R. roxburghii Tratt. (Rosaceae) (RR) is an important crop in China due to its nutritional and medicinal values. RR frequently produces trichomes on the surfaces of a diverse range of organs, however a g...
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Chestnut rose, R. roxburghii Tratt. (Rosaceae) (RR) is an important crop in China due to its nutritional and medicinal values. RR frequently produces trichomes on the surfaces of a diverse range of organs, however a genetic component exists to the control of trichome development, with some cultivars having significantly fewer trichomes to others. Certain varieties have fruits that are thickly covered with macroscopic trichomes, which is an undesirable trait for fruit processing and consumption. However, smooth-fruit cultivars exist, such as R. roxburghii Tratt. f. esetosa Ku (RRE). Despite their economic importance, the anatomical features of trichomes have not been explored in detail for these two chestnut rose germplasms. Here, we investigate the ultrastructure of trichomes distributed on the stem, sepal, and fruit of RR and RRE using transmission electron microscopy (TEM). The internal structure of stem prickle trichomes in RR and RRE was oval in shape and did not contain nucleoli or other organelles. The cell walls of stem prickles in RR are thick and the intercellular spaces occupied with liquid, whereas the cells wall of stem prickles in RRE are thin and have air-filled intercellular spaces. The cells of sepal acicular trichomes in RR and glandular trichomes (GTs) of sepals in RRE had similar vacuole sizes, cytoplasm content, intercellular spaces, and arrangement of plastids within cells. However, there were osmiophilic granules present in the GTs of RRE. The flagelliform trichomes in the sepals of the two germplasms are composed of oval or rod-shaped cells. Although the flagelliform trichomes in the sepals of the two germplasms had a similar internal structure, and both contained starch grains and plastids with visible thylakoid membranes, the flagelliform trichomes in the sepals of RR had a thinner cell wall and a higher proportion of cytoplasm which was more evenly distributed across the cell. There were granules that stained heavily with osmium tetroxide w
Using the source identification and classification methodology described in UNEP standardized toolkit for dioxin re-leases, combined with research data over the past decade, the production and release of polychlorinat...
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Using the source identification and classification methodology described in UNEP standardized toolkit for dioxin re-leases, combined with research data over the past decade, the production and release of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/fs) from 6 major sectors in China were inventoried from 2003 to 2020, and were projected until 2025 based on current control measures and relevant industrial plans. The results showed that after ratification of the Stockholm Convention, China's production and release of PCDD/fs began to de-cline after peaking in 2007, demonstrating the effectiveness of preliminary control measures. However, the continual expansion of manufacturing and energy sectors, along with the lack of compatible production control technology, re-versed the declining trend of production after 2015. Meanwhile, the environmental release continued to decrease, but at a slower rate after 2015. If subject to current policies, production and release would remain elevated with an expanding gap in between. This study also established the congener inventories, revealing the significance of OCDf and OCDD in terms of both production and release, and that of PeCDf and TCDf in terms of environmental impacts. Lastly, through comparison with other developed countries and regions, it was concluded that room for further reduc-tion exists, but can only be achieved through strengthened regulations and improved control measures.
M. E. Rudin (1971) proved, under CH, that for each P-pointp there exists a P-point q strictly RK-greater than p. This result was proved under p = c by A. Blass (1973), who also showed that each RK-increasing co -seque...
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M. E. Rudin (1971) proved, under CH, that for each P-pointp there exists a P-point q strictly RK-greater than p. This result was proved under p = c by A. Blass (1973), who also showed that each RK-increasing co -sequence of P-points is upper bounded by a P-point, and that there is an order embedding of the real line into the class of P-points with respect to the RK-ordering. In this paper, the results cited above are proved under the (weaker) assumption that b = c. A. Blass asked in 1973 which ordinals can be embedded in the set of P-points, and pointed out that such an ordinal cannot be greater than c+. In this paper it is proved, under b = c, that for each ordinal a < c+, there is an order embedding of a into P-points. It is also proved, under b = c, that there is an embedding of the long line into P-points.
Direct-current comparator bridges (DCC) are the working horses of primary resistance metrology in the intermediate resistance range. Having a ratio accuracy reaching 10-7 or better, they allow the realization of resis...
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Direct-current comparator bridges (DCC) are the working horses of primary resistance metrology in the intermediate resistance range. Having a ratio accuracy reaching 10-7 or better, they allow the realization of resistance scales and the calibration of artifact standard resistors for customers. In this paper we compare the performances of three commercial DCC bridges, by performing measurements on resistors in decadal ratios (1 omega to 10 k omega) of very high stability in a thermostated environment. The results show that the three bridges give mutually compatible results within the manufacturer's specifications, therefore mutually validating the bridges;nevertheless, the readings time series show quite different statistical behavior, with internal correlations, making an evaluation of the Type A measurement uncertainty not trivial.
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