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A series of novel monoazo disperse dyes based on N-carboxylic acid-1,8-naphthalimides have been synthesized via 4-(4-amino-1,8-naphthalimido) butanoic acid as diazo components and various couplers. The synthesized dyes were characterized with elemental analysis, differential scanning colorimetry, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and UV-visible spectroscopic techniques. The molar extinction coefficient, wavelength maxima, and solvatochromism effect were obtained using chloroform, acetone, and N,N-dimethyl formamide as solvent. The results showed that the synthesized dyes had molar extinction coefficient of 20908 to 38939 l mol−1 cm−1, wavelength maxima of 409–549 nm, and positive solvatochromism by changing solvent from chloroform to N,N-dimethyl formamide. The synthesized dyes were applied on poly(ethylene terephthalate) using high temperature method. Dyes 1 and 2 showed high build-up properties on poly(ethylene terephthalate), whereas dyes 3 and 4 offered medium build-up. All the dyes offered excellent heat fastness, good wash and rubbing fastnesses on poly(ethylene terephthalate) fabrics. The hydrolysis of the synthesized dyes in alkali media indicated that the presence of a carboxylic acid group within the dye molecules provides alkali-clearable potential.  相似文献   
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The trnL (UAA) intron and the intergenic spacer between the 3′ exon of trnL (UAA) and trnF (GAA) sequences were used as genetic markers for differentiating Ficus carica cultivars and establishing refined genetic relationships. The study was based on 20 fig cultivars, collected from south and centre of Tunisia. Since, the intron was thought to be more variable among close relatives than is the chloroplast spacer. The size of these non-coding regions varied from 554 to 589 and from 989 to 1022 bases pairs for the intron and the combined sequences correspondingly. The average of GC content was 33.9% and 34.6% in the intron and the combined intron and spacer respectively. High values of A + T contents were detected in both data sets and may explain the high proportions of transversions founded. The observed variation pattern of plastid DNA provides evidence of an important genetic diversity. The overall transition/transversion bias (R) was 0.202 in the intron and 0.27 in the combined regions. The RI index of 0.592 indicates that these combined sequences have clearly more homoplasy then the intron (RI = 0.705) and spacer (RI = 0.777) sequences separately. Phylogenetic trees were generated based on maximum parsimony (MP) and neighbor-joining (NJ) analysis of the chloroplast sequences data. Results proved that a typically continuous genetic diversity characterizes the local fig germplasm. In fact, relationships inferred from the cpDNA analysis suggest several clades, which do not show geographical or tree sex correspondence. Although the level of apparent diversity is considerable, we may conclude that non-coding regions of chloroplast genome provide a new and practical opportunity to evaluate genetic diversity and to discriminate fig cultivars. Revealed cytoplasmic DNA markers are reliable to elaborate a molecular data base to conduct management and breeding programs on local fig germplasm.  相似文献   
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Fifteen plastid fragments were amplified from a set of Tunisian date-palm accessions by PCR with consensus primers and analysed by RFLP. Polymorphic DNA bands were obtained as reliable molecular markers to estimate genetic distances among the accessions and to examine their phylogenetic relationships. The ctDNA PCR-RFLP method permitted the identification of two haplotypes that differ in the presence or absence of the HinfI restriction site. Phenetic groups composed of cultivars clustered together but does not constitute monophyletic groups. This typology agrees with the haplotypes' organization and provides a common genetic background within the implied varieties.  相似文献   
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In this study, we report on the relationship between individual antioxidant carotenoids, phenolic fractions, and flavonoids and attenuating NaCl toxicity in two contrasting varieties of lettuce (Lactuca sativa L., var. Verte and Romaine), as a means of developing more precise targets for lettuce breeding. In seedling leaves, carotenoid levels increased under NaCl stress in Verte, but remained unchanged in Romaine. Chlorogenic acid (CGA), a soluble polyphenol abundantly present in leaves, was the only phenolic acid that accumulated significantly in both varieties and was predominant under salinity. Remarkably, CGA was more prominent in Verte than Romaine at moderate salinity levels (100 mM). Foliar flavonoid levels were also differentially increased in both seedling types grown under 100 mM NaCl, but dropped significantly in both varieties under 200 mM NaCl. Germination, which was overall more salt‐resistant in Romaine, was significantly increased under salt stress by application of low dosage (10–6 to10–5 M) of CGA to Verte, but not to Romaine. These results suggest that CGA is involved in modulating NaCl‐induced oxidative‐stress responses during seed germination in Verte.  相似文献   
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BACKGROUND: Accurate measurements of physical characteristics of bone are essential for diagnosis, assessment of change following treatment, and therefore, indirectly, for evaluation of new forms of therapy. This is particularly true of osteoporosis and aging skeleton, in which fractures occur easily. METHODS: In this study an ultrasonic system was set-up and calibrated on Plexiglas tubes of variable thickness then used to detect the cortical bone thickness change in calf and bovine adult femurs. Lamb waves have been generated and detected using a pair of Piezoelectric point transducers (transmitter and receiver) operating at 60 kHz in contact with the surface of the bone. RESULTS: A link has been established between the ultrasound velocity and the bone thickness. On the other hand, the density variation has been also investigated by the simulation of the bone decalcification chemically. The results show that the velocity is very sensitive to both thickness and density, its value reduces as the cortical bone thickness and density decrease. CONCLUSION: This technique might be considered in the attendance of certain bone diseases expressing itself by gradual change in physical properties.  相似文献   
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The genetic diversity of 18 Tunisian fig cultivars was investigated at the DNA level using the Inter Simple Sequence Repeat (ISSR) associated with the Polymerase Chain Reaction (PCR). Using a set of primers, the most informative ones were selected that were characterized by an important Resolving power value of 29.6. A total of 47 discernible fragments were scored from samples, with a mean of 11.7 fragments per primer. The 90.4% of sample that were polymorphic were scored as molecular markers to examine the Tunisian fig germplasm polymorphism at DNA level. A large genetic diversity as related to ISSR patterns was found within the local Tunisian fig germplasm. An UPGMA dendrogram exhibits the unstructured variability in this crop. Moreover, the principal component analysis shows that the observed diversity was typically continuous. Our data provide a large number of ISSR markers that are useful in the fingerprinting of Ficus carica L. cultivars, and in the understanding of the genetic relationships among these accessions.  相似文献   
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Crop coefficients of some plants have been provided by the Food and Agricultural Organization albeit crop coefficients for different medicinal plants such as black cumin (Nigella sativa L.) have not been determined so far. Experiments were carried out during 2 years (2010 and 2011) to determine the water requirements, single and dual crop coefficients of black cumin using drainable lysimeter in a semi-arid region. In this study, black cumin water requirement was determined to be 724 mm by water balance method. The reference evapotranspiration was estimated by Penman–Monteith method. Finally, single and base crop coefficients for initial, development, middle and final stages of black cumin growth were determined to be as 0.59, 0.91, 1.29, 0.78 and 0.24, 0.71, 1.09 0.78, respectively. In order to estimate black cumin evapotranspiration by meteorological parameters, multiple regression models were presented. The results of the study showed that the determination of black cumin water requirements with dual crop coefficients had a less difference as compared to the results obtained from regression model. The total dry matter produced was 9.48 kg/ha per mm of irrigation water applied, seed yield was 3.10 kg/ha per mm of irrigation water applied, and oil content was 31 %.  相似文献   
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This study was conducted on nine heads of normal adult one-humped camels. The specimens were collected from Cairo slaughterhouse. The nasal cavity in the freshly collected samples were dissected and photographed. The specimens for microscopic studies were fixed in different fixatives and prepared to examine by light and scanning electron microscope (SEM). The nasal cavity of the camel was studied grossly and by using of light and scanning electron microscope. Specimens from different regions of this cavity were subjected to different histological stains and also demonstrated by the acid and alkaline phosphatases. Gross morphological examination of this cavity showed its three parts: rostral part (the nasal vestibule) covered with skin of usual structure then it lined with smooth mucosa. The middle part (respiratory) had dorsal, middle and ventral nasal conchae, but the caudal part (olfactory) contained the ethmoidal concha. The lining mucosa of the camel nasal cavity was similar to that of other mammals, but there were some differences: the respiratory epithelium showed a small number of goblet cells and there were a mixture of acidic and neutral mucins inside the epithelial and glandular mucous cells. Strong acid and alkaline phosphatase reaction was observed in the lining epithelium of the nasal cavity. By SEM, it showed the surface epithelial layer of the nasal cavity mucosa in three regions (vestibule, respiratory and olfactory) and resulted that it was stratified cuboidal to columnar epithelium, ciliated pseudostratified columnar epithelium with few goblet cells or olfactory mucosa containing neurosensory olfactory cells. This study aimed to investigate the anatomical features, the histological and histochemical structures of the nasal cavity in one humped camel. The findings of this study were discussed with the previous works in this field with the other domestic animals.  相似文献   
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