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Cement factory emissions into air cause serious air pollution and affect the plant and animal life in the environment. Herein, we report the effects of cement industry emissions (O3, SO2 and NO2) in air, as pollutants, at Riyadh City on Datura innoxia Mill. plant. Morphological characters including plant height, leaves area and number, fresh and dry weight of shoot and root systems of D. innoxia showed a significant reduction from their normal control plants as a response to exposure to pollutant emissions. Chlorophyll and carotenoid contents recorded reductions in values compared to control plant, and the lowest values of chlorophyll A, B, total chlorophyll, carotenoids and total pigments were 0.431, 0.169, 0.60, 0.343 and 0.943 mg/g respectively at a distance of 1–5 m from the cement factory in fruiting stage. These changes in values may be attributed to a probable deceleration of the biosynthetic process rather than degradation of pigments. Further D. innoxia showed a significant (P < 0.01) reduction in non-reducing and total sugars, protein and total lipid contents compared with the control plant. The root system recorded the lowest values of reducing sugars (0.350 mg/g f. wt.), non-reducing sugars (0.116 mg/g f. wt.), total sugars (0.466 mg/g f. wt.), protein content (0.931 mg/g f. wt.) and total lipids content (0.669 mg/g f. wt.) in fruiting stage at a distance of 1–5 m from the cement factory. The peroxidase activity of shoot and root systems of the studied plant was also significantly higher than those of control plant. Thus a highest value of (29.616 units/g f. wt.) peroxidase activity was recorded in vegetative stage of shoot system at a distance 1–5 m from the cement factory. Results of the study indicated that cement industry emission strongly influence the physiology and morphology of date palm D. innoxia which contribute date fruits, a staple food in the Arab world.  相似文献   
2.
The harvested eggs of Rhynchophorus ferrugineus are ovo-cylindrical shaped, averaged 1.09 mm in length and 0.43 mm in width, with ratio of L\W 4.42. The chorionic layer of electron dense material is seen covering the exochorion structure of the eggs. The egg main body chorion exhibits a polygonal pattern and architecture surface of the egg is supported by a system of irregular interconnecting grooves. The micropylar apparatus of the eggs of the Red Palm Weevil, R. ferrugineus is described in the present study for the first time. Two micropylar openings are found closed to the center of the posterior wide pole of the egg. Each micropylar opening presents a single small orifice and its surrounding chorion is porous and densely set with tiny projections allowing the spermatozoa to penetrate the egg. Respiratory aeropyles are distributed on the borders of reticulations in the area chorionic surface of egg capsule. The hatching region is detected on the anterior part at the opposite side of the egg. Changes in the appearance and shape of R. ferrugineus eggs as well as the incidence of embryonic development are observed.  相似文献   
3.
Spermiogenesis, in particular the head differentiation of Diplometopon zarudnyi, was studied at the ultrastructural level by Transmission Electron Microscope (TEM). The process includes acrosomal vesicle development, nuclear elongation, chromatin condensation and exclusion of excess cytoplasm. In stage I, the proacrosomal vesicle occurs next to a shallow fossa of the nucleus, and a dense acrosomal granule forms beneath it. This step commences with an acrosome vesicle forming from Golgi transport vesicles; simultaneously, the nucleus begins to move eccentrically. In stage II, the round proacrosomal vesicle is flattened by projection of the nuclear fossa, and the dense acrosomal granule diffuses into the vesicle as the fibrous layer forms the subacrosomal cone. Circular manchettes surrounded by mitochondria develop around the nucleus, and the chromatin coagulates into small granules. The movement of the nucleus causes rearrangement of the cytoplasm. The nucleus has uniform diffuse chromatin with small indices of heterochromatin. The subacrosome space develops early, enlarges during elongation, and accumulates a thick layer of dark staining granules. In stage III, the front of the elongating nucleus protrudes out of the spermatid and is covered by the flat acrosome; coarse granules replace the small ones within the nucleus. One endonuclear canal is present where the perforatorium resides. In stage IV, the chromatin concentrates to dense homogeneous phase. The circular manchette is reorganized longitudinally. The Sertoli process covers the acrosome and the residues of the cytoplasmic lobes are removed. In stage V, the sperm head matures.  相似文献   
4.
Trichophyton rubrum is one of the major disease causing pathogens in human; mainly it causes tinea pedis, tinea cruris and tinea corporis. Cytochrome P450 which considered to be an important protein that can impact ergosterol biosynthesis pathway. B. aegyptiaca is rich source of secondary metabolites with tremendous medicinal values and it has sweet pulp, leaves with spine, strong seed and oily kernel. The epicarp of the fruit was taken for this study to inhibit T. rubrum using in vitro and in silico techniques. The epicarp portion was extracted using various solvents and water. The anti-dermatophytic activity on T. rubrum of these extracts was assessed utilizing poison plate technique with 5 individual concentrations. The fractioned chloroform extract of epicarp had fully inhibited the growth of T. rubrum at 3 mg/ml. Further, the chloroform extract was subjected to LC-MS analysis, in total, 40 compounds were elucidated. Then, the derived compounds were included for predicting ADMETox properties using Qikprop module. From the analysis 40 compounds were identified to be eligible for docking process. Then the desirable compounds, drug Ketoconazole were subjected to docking analysis using Glide module of Schrödinger. It shows that Platyphylloside has better docking result than other compounds and drug Ketoconazole. Further, MD simulation was carried out for Ketoconazole-Cyp450 and Platyphylloside-CYP450 complexes using Desmond, Schrödinger. MD simulation study also confirmed that the Platyphylloside-CYP450 complex more stable. This study suggests that Platyphylloside may act as potential inhibitor and it could be further subjected to experimental analysis to inhibit the T. rubrum growth.  相似文献   
5.
The earwig, Anisolabis maritima (Dermaptera: Carcinophoridae), is one of the most significant insects in KSA because, it was recorded in Saudi Arabia as a beneficial predator on eggs and newly hatched larvae of the red palm weevil, Rhyncophorus ferrugineus. We examined the external morphology of the antennal sensilla of males and females of A. maritima using scanning electron microscopy (SEM). The filiform antennae of A. maritima were of the conventional type comprising a basal scape, pedicle and a long, thread-like flagellum, which was composed of 12 flagellomeres of males and 16 flagellomeres of females. Six morphologically unique sensillar types were found and described on the antennae of males and females of A. maritima. Of those identified, there were three types of porous trichoid sensilla (long, curved and arcuate), and two types of basiconic sensilla (short and curved), and one type of aporous trichoid sensilla. The shape, external morphology and array of sensilla on the antennae of males and females of A. maritima were similar.  相似文献   
6.
Salinity is one of the largest stresses blocking horizontal and vertical expansion in agricultural lands. Establishing salt-tolerant genotypes is a promising method to benefit from poor water quality and salinized lands. An integrated method was developed for accomplishing reliable and effective evaluation of traits stability of salt-tolerant wheat. The study aims were to estimate the genetic relationships between explanatory traits and shoot dry matter (SDM), and determine the traits stability under three salinity levels. Morphophysiological and biochemical traits were evaluated as selection criteria for SDM improvement in wheat for salinity tolerance. Three cultivars and three high-yielding doubled haploid lines (DHLs) were used. Three salt (NaCl) levels (control (washed sand), 7 and 14 dS m−1) were applied for 45 days (at the first signs of death in the sensitive genotypes). All morphophysiological traits gradually decreased as salinity levels increased, excluding the number of roots. Decreases were more visible in sensitive genotypes than in tolerant genotypes. All biochemical traits increased as salinity levels increased. Variance inflation factors (VIFs) and condition number exhibited multicollinearity for membrane stability index and polyphenol oxidase activity. After their removal, all VIFs were <10, thereby increasing path coefficient accuracy. Total chlorophyll content (CHL) and catalase (CAT) provided significant direct effects regarding genetic and phenotypic correlations for the three salinity levels and their interactions in path analysis on SDM, indicating their stability. CHL and CAT had high heritability (>0.60%) and genetic gain (>20%) and highly significant genetic correlation, co-heritability, and selection efficiencies for SDM. CHL and CAT could be used as selection criteria for salinity tolerance in wheat-breeding programs. The tolerated line (DHL21) with the check cultivar (Sakha 93) can be also recommended as novel genetic resource for improving salinity tolerance of wheat.  相似文献   
7.
Diplometopon zarudnyi, a worm lizard belongs to amphisbaenia under trogonophidae family. This species exists in limited areas of the Arabian Peninsula and is an oscillating digger found in sub-surface soils. The present study aimed to investigate the sperm tail differentiation in D. zarudnyi. Ten male adults of D. zarudnyi were collected from Riyadh during April–May 2011. To study the sperm tail at the ultrastructural level the testes were fixed in 3% glutaraldehyde, than post fixed in 1% osmium tetaroxide followed by dehydration in ethanol grades; samples were cleared in propylene oxide and embedded in resin. Tail formation begins by the moving of centrioles and mitochondria towards the posterior pole of sperm head. Simultaneously many microtubules of the midpiece axoneme were enclosed by a thick layer of granular material. Mitochondria of midpiece lie alongside the proximal centriole which forms a very short neck region and possess tubular cristae internally and concentric layers of cristae superficially. During this course a fibrous sheath surrounds the axoneme of mid and principal piece. At the end dissolution of longitudinal manchette takes place. The mitochondria then rearrange themselves around the proximal and distal centrioles to form a neck region. Later, the fibrous sheath surrounds the proximal portion of the flagella. This part along with sperm head of D. zarudnyi provides a classical model that could be used in future for evolutionary and phylogenetic purposes of class reptilia.  相似文献   
8.
The earwig Anisolabis maritima is a cosmopolitan insect with a worldwide distribution, omnivorous in feeding, eating the eggs of different insects. Recently recorded in Saudi Arabia as a beneficial predator on eggs and newly hatched larvae of the red palm weevil Rhyncophrous ferrugineus, scanning electron microscopy (SEM) observations revealed the presence of different kinds of receptor sensillae occurring on the head and mouth parts of A. maritime. The sensillae are the same, but differ in numbers on both sexes. The head surface bears three subtypes of trichoid sensillae, one type of ceoloconica. Labrum, labium, labial palps and maxillary palps, possess different kinds of sensillae. Three subtypes of trichoid have been identified on the labrum. The labium contained one type of tricoid and basiconic sensillae. There are great numbers and numerous sensillae cheatica differing in length distributed on the maxillary and the labial palps on all segments between other stutter spines. The last terminal segment of maxillary or labial palps bears the greatest number of the sensillae cheatica. Adult A. maritima may be introduced in the future as a beneficial predator of eggs of R. ferrugineus as a tool for integrated pest management.  相似文献   
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10.
Sodium leak channel, nonselective (NALCN) is a voltage-independent and cation-nonselective channel that is mainly responsible for the leaky sodium transport across neuronal membranes and controls neuronal excitability. Although NALCN variants have been conflictingly reported to be in linkage disequilibrium with schizophrenia and bipolar disorder, to our knowledge, no mutations have been reported to date for any inherited disorders. Using linkage, SNP-based homozygosity mapping, targeted sequencing, and confirmatory exome sequencing, we identified two mutations, one missense and one nonsense, in NALCN in two unrelated families. The mutations cause an autosomal-recessive syndrome characterized by subtle facial dysmorphism, variable degrees of hypotonia, speech impairment, chronic constipation, and intellectual disability. Furthermore, one of the families pursued preimplantation genetic diagnosis on the basis of the results from this study, and the mother recently delivered healthy twins, a boy and a girl, with no symptoms of hypotonia, which was present in all the affected children at birth. Hence, the two families we describe here represent instances of loss of function in human NALCN.  相似文献   
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