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The issue of climate change caused by global warming has become a major concern and challenge around the world, requiring comprehensive countermeasures. Agriculture is the most affected part of climate change and Iran's agriculture economy is at risk because of hot and dry and damages due global climate changes. This study investigates the effects of climatic variables temperature, such as precipitation, carbon and dioxide emission on total crop production in Iran from 1971 to 2020 using a fully modified conventional least squares econometric model (FMOLS). Chemical fertilizer and crop area variables, as well as fixed capital in agricultural have machinery, also been used as indicators of technology. The results showed that all variables had a significant effect on production. The average annual temperature and total annual rainfall its had an inverse U-shaped relationship with production, and were significant. Fertilizer and crop area variables had a positive effect, while CO2 had a negative relationship on total crop production in Iran. The findings of this study can be used to provide strategic plans for policymakers in the face of climate change. It is suggested that the government invest more in the mechanization of the agricultural sector and provide facilities and credits with priority given to farmers' education and the use of temperature-resistant varieties, and also act regionally against climate change.

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Event-related potentials (ERPs) derived from electroencephalography (EEG) have proven useful for understanding linguistic processes during language perception and production. Words are commonly produced in sequences, yet most ERP studies have used single-word experimental designs. Single-word designs reduce potential ERP overlap in word sequence production. However, word sequence production engages brain mechanisms in different ways than single word production. In particular, speech monitoring and planning mechanisms are more engaged than for single words since several words must be produced in a short period of time. This study evaluates the feasibility of recording ERP components in the context of word sequence production, and whether separate components could be isolated for each word. Scalp EEG data were acquired, while participants recited word sequences from memory at a regular pace, using a tongue-twister paradigm. The results revealed fronto-central error-related negativity, previously associated with speech monitoring, which could be distinguished for each word. Its peak amplitude was sensitive to Cycle and Phonological Similarity. However, an effect of sequential production was also observable on baseline measures, indicating baseline shifts throughout the word sequence due to concurrent sustained medial-frontal EEG activity. We also report a late left anterior negativity (LLAN), associated with verbal response planning and execution, onsetting around 100 ms before the first word in each cycle and sustained throughout the rest of the cycle. This work underlines the importance of considering the contribution of transient and sustained EEG activity on ERPs, and provides evidence that ERPs can be used to study sequential word production.

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Poly(vinyl chloride) membrane electrode, that is highly selective and sensitive to Cu(II) ions, was developed by using 2,2'-dithiodianiline and dibutyl phthalate as carrier and plasticizer, respectively. The electrode exhibits good potentiometric response for Cu(II) over a wide concentration range (5.0x10(-2)-7.0x10(-7) mol l(-1)) with Nernstian slope of 30+/-1 mV per decade. The response time of the electrode is 10 s and it has been used for a period of one month and exhibits good selectivity towards Cu(2+) in comparison to alkali, alkaline earth, transition and heavy metal ions, with no interference caused by Pb(2+), Cd(2+) and Fe(+2) which are known to interfere with many other copper electrodes.

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Two indirect immunofluorescence (IIF) assays, two enzyme-linked immunosorbent assays (ELISAs) and the carbon immunoassay (CIA) for determination of antibodies to Encephalitozoon cuniculi were compared using 210 sera of rabbits, 135 of which originated from seven infected colonies, while 75 originated from four uninfected colonies. There was no evidence of a difference between the different assays with respect to the number of positive sera. There was a clear correlation between the quantitative response measured by IIF and CIA and the other assays, and between both IIF tests, while no such correlation was found in the quantitative response measured by ELISAs, which might be explained by the less quantitative nature of the ELISA. Therefore quantitative determination of antibodies to E. cuniculi should be performed by IIF and not by ELISA. The nosographic sensitivities N1 and specificities N2 of the assays were > or = 0.94 and > or = 0.97 respectively. Small differences in N1 and N2 between the assays, although not statistically significant, were responsible for differences in the calculated predictive values of a positive test and of a negative test. As expected, the magnitude of these differences depended on the fraction of positive sera sampled from a given colony. There was strong evidence of such a difference between the fraction of positive sera found in different colonies, but the sample size from some colonies was too small to allow any conclusion, whether this was due to differences in the prevalences of the infection in the colonies or something else. We conclude that any of the assays will be suitable for the routine health monitoring of laboratory rabbit colonies for E. cuniculi infection, as recommended by the Federation of European Laboratory Animal Science Associations.

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A method for the extraction-spectrophotometric determination of palladium with 2,2'-dithiodianilline (DTDA) is described. DTDA-Pd(II) complex is extracted from an aqueous solution with pH 3 into isobutyl methyl ketone (IBMK) layer. The absorbance is measured at 397 nm and the molar absorptivity found to be 1.47x10(6) l mol(-1) cm(-1). The complex system conforms to Beer's law over the range 0.3-220 ng ml(-1) palladium (II). The effect of pH (1-6), NaClO(4) concentration, DTDA concentration and shaking time were studied. The ratio of the metal ion to ligand molecules in the complex and its stability constant were found to be 1:1 and 1.45x10(6), respectively. The tolerance limit for many cations and anions have been determined. Finally the method has been applied successfully to the determination of palladium in synthetic mixtures, alloy and catalyst samples.