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Pesticide residues are decomposed by a number of microorganisms and used as a source of nitrogen and carbon. The discovery of new strains capable of tolerating and degrading toxic pesticides can increase the flexibility of strategic planning for environmental decontamination initiatives. Our goal was to isolate bacteria tolerant to different concentrations of 40% dimethoate (0-80 µg L-1) from soil samples, determine the optimization of cultural conditions (pH, temperature and incubation time), and examine the inhibitory/inducing effect on the plant growth enhancing traits. The most effective bacterial isolate was identified by biochemistry and phylogenetics, and was also tested for HPLC biodegradation. Data showed that only one strain (SH1) had the greatest tolerance to dimethoate after 72 hours at the highest concentrations (80 µg L−1), despite the fact that all isolates (SH1–SH7) showed some degree of tolerance. Furthermore, at the greatest concentration of dimethoate, the highest growth was observed by the SH1 isolate, which recorded 0.64 for optimum pH 7, 0.69 for optimum temperature 30 °C, and 0.79 for optimum incubation time 72 h. In the same context, isolate (SH1) recorded positive results in producing IAA, NH3, P solubilization, and siderophores at 60 µg L−1 compared to other tested isolates and different concentrations of dimethoate. Therefore, according to the biochemical characteristics and 16S rRNA sequence, SH1 isolate belonged to Bacillus subtilis that had GenBank accession number OQ347968. According to the results of HPLC biodegradation, after 7 days, B. subtilis OQ347968 had the highest rates of dimethoate elimination (80 mg L-1). These findings imply that B. subtilis OQ347968 has a great deal of ability to degrade dimethoate 40% in a variety of environmental conditions. [ABSTRACT FROM AUTHOR]

Premature diagnosis of transformer oil faults enables the operator for diagnosing the transformer condition and hence operating the transformer continuously without outage. DGA is one of the most popular chemical tests used for fault diagnosis and there are many techniques which have been developed in this regard. This paper presents a proposed DGA technique for transformer oil fault identification based on the results of the recently published techniques. The proposed technique has been constructed based on the integration between the outputs of two recently established DGA techniques; Conditional probability and artificial neural network. A total of 532 datasets, obtained from the Egyptian Electricity Transmission Company (EETC) with known faults, have been used for designing and testing the proposed technique. The proposed fault diagnostic technique's accuracy attained 86.6 %, which is higher than the results of the combined techniques; 81.7% for ANN and 82.8% for conditional probability technique. The proposed developed technique came to the conclusion that integrating several DGA techniques, with higher accuracy, enhances fault detection's overall accuracy. [ABSTRACT FROM AUTHOR]

Background and Aims Drought reduces plant productivity, especially in the susceptible species Brassica napus. Water stress, mimicked by applications of 10 % polyethylene glycol (PEG), elevates nitric oxide (NO) in root cells after a few hours, contributing to degradation of the root apical meristems (RAMs), the function of which relies on auxin and brassinosteroids (BRs). Phytoglobins (Pgbs) are effective NO scavengers induced by this stress. This study examines the effects of BnPgb1 dysregulation in dehydrating B. napus roots, and the spatiotemporal relationship between Pgb1 and activities of auxin and BRs in the regulation of the RAM. Methods Brassica napus lines over-expressing [BnPgb1(S)] or down-regulating [BnPgb1(RNAi)] BnPgb1 were exposed to PEG-induced water stress. The localization of BnPgb1, NO, auxin and PIN1 were analysed during the first 48 h, while the expression level of biosynthetic auxin and BR genes was measured during the first 24 h. Pharmacological treatments were conducted to assess the requirement of auxin and BR in dehydrating roots. Key Results During PEG stress, BnPgb1 protein accumulated preferentially in the peripheral domains of the root elongation zone, exposing the meristem to NO, which inhibits polar auxin transport (PAT), probably by interfering with PIN1 localization and the synthesis of auxin. Diminished auxin at the root tip depressed the synthesis of BR and caused the degradation of the RAMs. The strength of BnPgb1 signal in the elongation zone was increased in BnPgb1(S) roots, where NO was confined to the most apical cells. Consequently, PAT and auxin synthesis were retained, and the definition of RAMs was maintained. Auxin preservation of the RAM required BRs, although BRs alone was not sufficient to fully rescue drought-damaged RAMs in auxin-depleted environments. Conclusions The tissue-specific localization of BnPgb1 and NO determine B. napus root responses to water stress. A model is proposed in which auxin and BRs act as downstream components of BnPgb1 signalling in the preservation of RAMs in dehydrating roots. [ABSTRACT FROM AUTHOR]

Wood species identification and characterization of its weathering processes are crucial steps in the scientific approach of conservation of wooden cultural heritage. Many precious wooden objects of ancient Egypt are largely present in museums, nevertheless relatively little information is available concerning the nature of timber used and on their status of conservation. To address this gap, the wooden species of three relevant archaeological wood objects (statue, box, and coffin) arising from different Egyptian archaeological sites dated from the Old Kingdom (2,686–2,181 BC) to New Kingdom (1,550–1,069 BC) were deeply studied. Five hardwood and softwood species were identified belonging to Tamarix mannifera, T. gennessarensis, Ficus sycomorus, Vachellia nilotica, and Cedrus sp. Such data confirmed the recurrence of Vachellia and Tamarix among the most common timbers found in ancient Egypt. Scanning electron microscope, Fourier transform spectroscopy, and synchrotron x‐ray radiation diffraction were conducted to evaluate the archaeological wood deterioration. The formation of microcracks, biological degradation patterns (fungal colonization), or chemical characterization (accumulation of salts on and in‐between wooden cells) were detected. SEM micrographs showed the presence of fungal hyphae and conidial spores on the wooden cells. Significant changes in the chemical wood composition and decrease in the crystallinity index were detected. [ABSTRACT FROM AUTHOR]