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1.
Soil particle size distribution (PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains (D1 and D2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D1 and clay content (R2 = 0.924), a negative correlation between D1 and silt content (R2 = 0.801), and a negative correlation between D2 and sand content (R2 = 0.913). The geometric mean diameter of soil particles had a negative correlation with D1 (R2 = 0.569) and D2 (R2 = 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D1 and D2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D1 and D2 and particle size fractions. According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.  相似文献   
2.
Tropical Animal Health and Production - The present study was conducted to estimate autosomal and sex-linked genetic parameters by restricted maximum likelihood method using four different...  相似文献   
3.
Journal of Soils and Sediments - In urban areas, humans shape the surface, (re-)deposit natural or technogenic material, and thus become the dominant soil formation factor. The 2015 edition of the...  相似文献   
4.
The objective of this study was to compare the reproductive performance of cows affected by clinical endometritis (CE) following treatment with an intrauterine infusion of 50% dextrose solutions (DEX) and liquid paraffin (LP) as alternative therapies with routine treatments including PGF2α injection and intrauterine infusion of oxytetracycline (OTC). Moreover, the reproductive indices of cows treated with endometritis were compared with those of healthy ones. At postpartum reproductive tract examination (28–35 DIM) in one Iranian dairy farm, cows with CE without any selection were assigned to four groups: (a) OTC, a common treatment in Iran, was administered (5 g) to 396 cows, (b) PGF2α (PG) was injected to 496 cows, (c) dextrose solution (DEX): intrauterine infusion of 50% dextrose solution (200 ml) was done in 427 cows, and (d) liquid paraffin (LP) was administered (100 ml) to 423 cows via intrauterine route. We further assigned 2,233 clinically healthy cows to the control group. The incidence of endometritis was 41.6% in this study. Based on the results of reproductive indices including median days to first AI, days open (DO), first service conception rate, conception rate in 2nd and 3rd services, conception rate in all three services, pregnancy rate < 100 days and pregnancy rate < 200 days, except for median days to first AI in other reproductive indexes, reproductive performance was significantly lower in LP group compared with the healthy cows and other treatment groups (p < 0.05). Except for the first service conception rate and proportion of cows pregnant before 100 days in milk (DIM), there existed no significant difference between the DEX group and the control as far as reproductive performance is concerned (p ≥ 0.05). The first service conception rate was recognizably lower in DEX group compared with OTC and PG (p < 0.05). In conclusion, the use of a non‐antibiotic special solution of dextrose 50% is a good alternative to antibiotic agents concerning the treatment of CE in dairy cows.  相似文献   
5.
A factorial experiment was developed with two factors of the growing medium (v/v): 100% coconut fiber (CF), 75% vermicompost+25% perlite (VP), 25% zeolite+75% perlite (ZP), 75% peat+25% perlite (PP), 75% coco chip+25% perlite (CCP), 75% coconut fiber+25% perlite (CFP) and 100% perlite (P); and sodium bicarbonate (NaHCO3) (0, 20 and 40 mM) involving the growth of gerbera cv. Dafne. Compared with CF substrate, NaHCO3 in the nutrient solution caused significant decrease in vegetative and reproductive traits and nutrient concentration [especially iron, phosphorus, and magnesium (Fe, P and Mg)] in the rest of the media. The improved crop performance of plants grown onto CF substrate was attributed to their strong capacity to accumulate Fe in the aerial part under alkaline conditions and to maintain a better plant nutritional status (higher P and Mg). It is concluded that the use of CF substrate could provide a useful tool to improve alkalinity tolerance of gerbera plants under NaHCO3 stress.  相似文献   
6.
Tropical Animal Health and Production - Separation of autosomal and sex-linked direct additive genetic effects has significant role in sheep breeding programs. Hence, this study was conducted to...  相似文献   
7.
In recent years, considerable interest has been focused on the use of physiological parameters as selection criteria in salt tolerance ranking. Eighteen bread wheat (Triticum aestivum L.) landraces from the west area of the Urmia Saline Lake were grown in a greenhouse in the Department of Plant Biology and Halophytes Biotechnology Center, Azarbaijan University of Tarbiyat Moallem, Tabriz, Iran to study the effects of increasing levels of sodium chloride (NaCl) (control, 75, and 150 mM) on the plant leaves. The experimental design was factorial with a randomized complete block with three replications. The results showed salinity caused an obvious decrease in growth of all landraces. Physiological parameters such as lipid peroxidation, hydrogen peroxide (H2O2) content, and cell membrane injury increased with increasing salinity levels with different degrees among the landraces. Salt stress increased the sodium (Na+) accumulation coupled with a decrease in leaf potassium (K+) depending on salinity levels. The analysis of variance showed significant effects of salinity, landraces and their interactions in all studied parameters. The landraces were ranked for salt tolerance indexes, and cluster group ranking ordered landraces from tolerant to sensitive and their properties for salt stress tolerance are open for further research.  相似文献   
8.
Journal of Soils and Sediments - Sb is a metalloid that naturally occurs in traces in the Northern German Lowland Area, only. Its frequent and still growing demand for industrial purposes and its...  相似文献   
9.
Background:The MET receptor is a critical member of cancer-associated RTKs and plays an important role in different biological activities, including differentiation, migration, and cell proliferation. Methods:In this study, novel MET inhibitors were introduced and applied on esophageal squamous carcinoma cell line KYSE-30, and the level of proliferation and migration, as well as the activated form of MET receptor protein were assessed in the examined cells. The human KYSE-30 cell line was cultured according to ATCC recommendations. The mRNA level of the MET gene was measured in the examined cell line using the quantitative RT-PCR assay. Cytotoxicity evaluation test was performed at different concentrations of heterocyclic anti-MET compounds (i.e. D1, D2, D5, D6, D7, and D8). Finally, the capability of these compounds in MET receptor inhibition was evaluated using the migration assay and Western blot. All experiments were performed in triplicate and repeated three times with similar results. Results:Cell growth and proliferation were significantly inhibited (p ≤ 0.05) by all the above-mentioned compounds. Moreover, the majority of compounds significantly prevented the cell migration (p ≤ 0.05) and inhibited MET autophosphorylation. Interestingly, the level of phosphorylated MET was significantly correlated with KYSE-30 cell migration. Conclusion:The obtained data introduced and confirmed the biological activities of the mentioned novel compounds in KYSE-30 cells and proposed that the therapeutic inhibition of MET with these compounds may be a powerful approach for inhibiting cancer cell migration and proliferation although some structural optimizations are needed to improve their inhibitory functions. Key Words: c-MET, Esophageal squamous cell carcinoma, Receptor tyrosine kinases  相似文献   
10.
Draught animal technology (DAT) can potentially play a central role in agriculture transformation for traditional farmers. This study surveyed the state of DAT in En-Nhoud area, North Kordofan State, Sudan in an attempt to have a clear view of the changes brought about by introducing the technology. The study followed the cross-sectional survey design. Farmers were selected from ten clusters (villages) and data were collected using questionnaires and face to face interviews with farmers in addition to group discussions with them and the different actors in the field. The results showed that farmers appreciate the role played by DAT, but they highlighted the need for further capacity building and technical backup. Harnessing issues are not well understood and applied by the farmers. The different actors involved in DAT in the area lack networking and coordination, and this reflected on the many problems and constraints faced by the farmers.  相似文献   
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