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61.
Rao B Anderson TA Orris GJ Rainwater KA Rajagopalan S Sandvig RM Scanlon BR Stonestrom DA Walvoord MA Jackson WA 《Environmental science & technology》2007,41(13):4522-4528
A substantial reservoir (up to 1 kg ha(-1)) of natural perchlorate is present in diverse unsaturated zones of the arid and semi-arid southwestern United States. The perchlorate co-occurs with meteoric chloride that has accumulated in these soils throughout the Holocene [0 to 10-15 ka (thousand years ago)] and possibly longer periods. Previously, natural perchlorate widely believed to be limited to the Atacama Desert, now appears widespread in steppe-to-desert ecoregions. The perchlorate reservoir becomes sufficiently large to affect groundwater when recharge from irrigation or climate change flushes accumulated salts from the unsaturated zone. This new source may help explain increasing reports of perchlorate in dry region agricultural products and should be considered when evaluating overall source contributions. 相似文献
62.
Anelsy Ramos-Guerrero Ramsés Ramón González-Estrada Greta Hanako-Rosas Silvia Bautista-Baños Gustavo Acevedo-Hernández Martin Ernesto Tiznado-Hernández Porfirio Gutiérrez-Martínez 《Food science and biotechnology》2018,27(3):755-763
Soursop (Annona muricata) is a tropical fruit that can be infected by Colletotrichum gloeosporioides and Rhizopus stolonifer. Traditional methods used for postharvest disease control include the application of fungicides, however due to their excessive use, as well as their persistence in the environment, the development of new strategies that control pathogens are required. The application of chitosan (Chi), salicylic acid (SA) and methyl jasmonate (MJ) is an environmentally-friendly alternative with antimicrobial properties and also induces defense mechanisms in plant tissues. In this study, Colletotrichum was reactivated and Rhizopus was identified using morphological features and molecular tools. In vitro, the application of 0.5 and 1.0% of Chi alone or in combination with SA and MJ decreased mycelial growth and sporulation, a complete inhibition of spore germination was obtained. Thus, the application of Chi in combination with SA and MJ could be a smart strategy to inhibit the development of pathogens that attack soursop fruit. 相似文献
63.
Greta Falavigna 《Expert systems with applications》2012,39(2):1784-1792
On a wake of Basel II Accord in 2004, banks and financial institutions can build an internal rating system. This work focuses on Italian small firms that are more hard to judge because quite often financial data are not simply available. The aim of this paper is to propose a simulation model for assigning rating judgements to these firms, using poor financial information.The proposed model produces a simulated counterpart of Bureau van Dijk-K Finance (BvD) rating judgements. It is clear that there are problems when small firms must be judged because it is difficult to obtain financial data; indeed in Italy these enterprises must deposit the balance-sheet in reduced form. Suggested methodology is a three-layer process where each of them is formed by, respectively, one, two and four feed-forward artificial neural networks with back-propagation algorithm. The proposed model is a good solution for evaluating small firms with poor financial information but not only: the research underlines and supports the ability of artificial neural networks of learning and reproducing some aspects or some features or behaviours of reality. 相似文献
64.
Nikolina Liović Andre Bratanić Zoran Zorić Sandra Pedisić Anet Režek Jambrak Greta Krešić Tea Bilušić 《International Journal of Food Science & Technology》2021,56(4):1996-2008
The influence of freeze-drying, pasteurisation and high-intensity ultrasound on gastrointestinal stability and antioxidant activity of cultivated blueberry phenolics was investigated. Quantitative and qualitative analyses were done before and after a two-phase in vitro digestion by human digestive enzymes. Antioxidant capacity of blueberry phenolics before and after simulated digestion was evaluated using DPPH and the FRAP assays. After the simulated gastric digestion phase, high stability of phenolics was determined, especially after freeze-drying. During the simulated duodenal digestion, the most affected compounds were anthocyanins. The average loss of quercetin derivatives was 60%, while in all ultrasound-treated samples, a 3-fold increase in the concentration of phenolic acids was observed. The highest antioxidant activity after in vitro gastric and duodenal digestion was determined in a freeze-dried sample. The results after in vitro digestion demonstrated that the use of freeze-drying and high-intensity ultrasound can ensure better gastrointestinal stability and higher antioxidant activity of blueberry phenolics. 相似文献
65.
66.
Investigated whether, in an unfamiliar, semipublic place, children as young as 18 mo of age would be sensitive to variations in the nature of social encounters between their mothers and an unfamiliar adult (E). Measures of the child's distance from the mother at the beginning of each 10-sec interval of the encounter, the percentage of 10-sec intervals spent by the child on the stranger's side of the room, frequency of child vocalizations to the mother, times child made physical contact with the mother, and frequency of smiling show that 18-mo-old children are already sensitive to background contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Greta Fein; David Johnson; Nancy Kosson; Linda Stork; Lisa Wasserman 《Canadian Metallurgical Quarterly》1975,11(4):527
Examined the toy preferences of 20-mo-old Ss under free play and modeling conditions. The relationship between toy familiarity and preference was also studied. The interaction between sex of child and sex-type of toy was significant. The hypothesis that toy contacts or imitation would be associated with toy familiarity was not supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
In this work, a new candying procedure with partial re-use of sugar syrup is proposed. Physicochemical analysis, together
with sensory evaluation, of candied celeriac samples was done. Candying was performed in a pilot unit at 65‡C, through three
cycles of 5 hours duration each. Sugar syrups of 75‡ Brix were used. Effects of 1 % (m/v) citric and 1 % (m/v) ascorbic acid
addition, as well as the drying of candied celeriac (60‡C for 8 h) were studied. Sugar syrup deterioration was estimated by
the concentration of hydroxymethylfurfural. The results obtained showed that there were no significant(P < 0.01) differences in total dry matter and total sugar content between samples, while the increases after drying were significant(P > 0.01). Differences were observed in sugar compositions between samples. After three cycles, samples turned lighter, with
decreasedL* values after drying. The celeriac from the first cycle of the ascorbic acid addition procedure was adjudged best with respect
to all quality parameters. The decreased concentration of hydroxymethylfurfural confirmed that re-use of sugar syrup is possible. 相似文献
69.
The creation and characterization of histidine-tagged fusion protein arrays using nitrilotriacetic acid (NTA) capture probes on gold thin films for the study of protein-protein and protein-DNA interactions is described. Self-assembled monolayers of 11-mercaptoundecylamine were reacted with the heterobifunctional linker N-succinimidyl S-acetylthiopropionate (SATP) to create reactive sulfhydryl-terminated surfaces. NTA capture agents were immobilized by reacting maleimide-NTA molecules with the sulfhydryl surface. The SATP and NTA attachment chemistry was confirmed with Fourier transform infrared reflection absorption spectroscopy. Oriented protein arrays were fabricated using a two-step process: (i) patterned NTA monolayers were first formed through a single serpentine poly(dimethylsiloxane) microchannel; (ii) a second set of parallel microchannels was then used to immobilize multiple His-tagged proteins onto this pattern at discrete locations. SPR imaging measurements were employed to characterize the immobilization and specificity of His-tagged fusion proteins to the NTA surface. SPR imaging measurements were also used with the His-tagged fusion protein arrays to study multiple antibody-antigen binding interactions and to monitor the sequence-specific interaction of double-stranded DNA with TATA box-binding protein. In addition, His-tagged fusion protein arrays created on gold surfaces were also used to monitor antibody binding with fluorescence microscopy in a sandwich assay format. 相似文献
70.
Greta Lindwall Peisheng Wang Ursula R. Kattner Carelyn E. Campbell 《JOM Journal of the Minerals, Metals and Materials Society》2018,70(9):1692-1705
Oxygen is always a constituent in “real” titanium alloys including titanium alloy powders used for powder-based additive manufacturing (AM). In addition, oxygen uptake during powder handling and printing is hard to control and, hence, it is important to understand and predict how oxygen is affecting the microstructure. Therefore, oxygen is included in the evaluation of the thermodynamic properties of the titanium-vanadium system employing the CALculation of PHAse Diagrams method and a complete model of the O-Ti-V system is presented. The β-transus temperature is calculated to increase with increasing oxygen content whereas the extension of the α-Ti phase field into the binary is calculated to decrease, which explains the low vanadium solubilities measured in some experimental works. In addition, the critical temperature of the metastable miscibility gap of the β-phase is calculated to increase to above room temperature when oxygen is added. The effects of oxygen additions on phase fractions, martensite and ω formation temperatures are discussed, along with the impacts these changes may have on AM of titanium alloys. 相似文献