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31.
Partial duplication of 11q is related to several malformations like growth retardation, intellectual disability, hypoplasia of corpus callosum, short nose, palate defects, cardiac, urinary tract abnormalities and neural tube defects. We have studied the clinical and molecular characteristics of a patient with severe intellectual disabilities, dysmorphic features, congenital inguinal hernia and congenital cerebral malformation which is referred to as cytogenetic exploration. We have used FISH and array CGH analysis for a better understanding of the double chromosomic aberration involving a 7p microdeletion along with a partial duplication of 11q due to adjacent segregation of a paternal reciprocal translocation t(7;11)(p22;q21) revealed after banding analysis. The patient's karyotype formula was: 46,XY,der(7)t(7;11)(p22;q21)pat. FISH study confirmed these rearrangement and array CGH technique showed precisely the loss of at least 140 Kb on chromosome7p22.3pter and 33.4 Mb on chromosome11q22.1q25. Dysmorphic features, severe intellectual disability and brain malformations could result from the 11q22.1q25 trisomy. Our study provides an additional case for better understanding and delineating the partial duplication 11q.  相似文献   
32.
Moringa oleifera is a less used, drought-tolerant tropical plant, rich in nutritionally and nutraceutically important bioactive compounds. It is native to India and now under cultivation in many countries, but no data is available on genetic variability. Three DNA marker techniques, i.e., random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and cytochrome P450 gene-based markers were used for the detection of genetic variability in eight Indian cultivars of M. oleifera, collected from various states of India. A total of 17 RAPD, 6 ISSR and 7 pairs of cytochrome P450-based markers generated 48.68, 48.57 and 40.00 % polymorphisms, respectively. The marker index (MI) for each of these marker systems (3.25 for RAPD, 4.73 ISSR and 2.95 for Cyt P450-based markers) suggest that ISSR markers are the most effective for assessment of genetic diversity. Based on the three types of marker data, the eight cultivars of M. oleifera were grouped into four sub-clusters in a dendrogram, but without any distinct geographical pattern. This suggests spread of planting material and high rates of gene flow through cross pollination. High bootstrap values (94.4 and 82.3) were obtained at major nodes of the dendrogram using the winboot software. The dendrogram and PCA plots generated from the binary data matrices of the three marker systems were found highly concordant to each other. This study reveals a huge genetic diversity among the cultivars and this can be utilised for conservation and cultivar development in breeding programmes to produce high yielding, nutritionally superior cultivars.  相似文献   
33.
The initial microorganism adhesion on substrate is an important step for the biofilm formation. The surface properties of the stainless steel and B. cereus were characterized by the sessile drop technique. Moreover, the physicochemical properties of surface adhesion and the impact of bio adhesion to the stainless steel were determined at different time of contact (2, 4, 7, 9 and 24 h). The results showed that the strain was hydrophilic (Giwi = 3.37 mJ/m2), whereas the substratum has hydrophobic character (Giwi = ?57.6 mJ/m2). Stainless steel surface presents a weak electron-donor character (γ? = 4.1 mJ/m2) conversely to B. cereus that presents an important parameter (γ? = 31.6 mJ/m2). The bio adhesion was investigated at different time of contact. The data analysis after 2 h, confirmed the adhesion of B. cereus with an amount of 10 cfu/cm2 which increased to 1.2104 cfu/cm2 after 24 h. Interestingly, despite the difference of hydropohbicity, the interaction between B. cereus and substratum was favored by the thermodynamic aspect of adhesion (ΔGadhesion < 0). Interestingly, the study of the effect of B. cereus adhesion on the stainless steel has revealed that, the substratum becomes hydrophilic (θ° = 41.3, ΔGiwi = 39.6 mJ/m2) and highly electron donor (Γ? = 52.9 mJ/m2) after 2 h of bio adhesion.  相似文献   
34.
Capsule Woodpigeon Columba palumbus nest-tree selection is affected by human disturbance, grazing and tree characteristics.

Aims To determine the characteristics of trees used for nesting by Woodpigeons under two levels of grazing and disturbance in a Holm oak Middle Atlas forest, Morocco.

Methods Woodpigeon nest-tree selection was investigated in highly disturbed and less-disturbed sites over two years (2010 and 2011). The features of nest-tree characteristics were determined by comparing the characteristics of trees used for nesting to those of randomly selected trees.

Results Tree physical characteristics, grazing intensity and level of human disturbance were the main factors determining selection for nest-trees. Woodpigeons chose nesting trees that were greater in height, larger in DBH, lower in base of the live crown, in denser stands and at greater distance from tracks.

Conclusions Forest management for Woodpigeon nest habitat selection should focus on controlling the access of vehicles especially trucks, introducing a rotating system of forest utilization for grazing and maintaining (without extending) the cereal crops. These recommendations may assist land managers to plan for continued persistence of this species in Middle Atlas forests.  相似文献   
35.
36.

Purpose

Rarely considered in environmental assessment methods, potential land use impacts on a series of ecosystem services must be accounted for in widely used decision-making tools such as life cycle assessment (LCA). The main goal of this study is to provide an operational life cycle impact assessment characterization method that addresses land use impacts at a global scale by developing spatially differentiated characterization factors (CFs) and assessing the extent of their spatial variability using different regionalization levels.

Methods

The proposed method follows the recommendations of previous work and falls within the framework and principles for land use impact assessment established by the United Nations Environment Programme/Society of Environmental Toxicology and Chemistry Life Cycle Initiative. Based on the spatial approach suggested by Saad et al. (Int J Life Cycle Assess 16: 198–211, 2011), the intended impact pathways that are modeled pertain to impacts on ecosystem services damage potential and focus on three major ecosystem services: (1) erosion regulation potential, (2) freshwater regulation potential, and (3) water purification potential. Spatially-differentiated CFs were calculated for each biogeographic region of all three regionalization scale (Holdridge life regions, Holdridge life zones, and terrestrial biomes) along with a nonspatial world average level. In addition, seven land use types were assessed considering both land occupation and land transformation interventions.

Results and discussion

A comprehensive analysis of the results indicates that, when compared to all resolution schemes, the world generic averaged CF can deviate for various ecosystem types. In the case of groundwater recharge potential impacts, this range varied up to factors of 7, 4.7, and 3 when using the Holdridge life zones, the Holdridge regions, and the terrestrial biomes regionalization levels, respectively. This validates the importance of introducing a regionalized assessment and highlights how a finer scale increases the level of detail and consequently the discriminating power across several biogeographic regions, which could not have been captured using a coarser scale. In practice, the implementation of such regionalized CFs suggests that an LCA practitioner must identify the ecosystem in which land occupation or transformation activities occur in addition to the traditional inventory data required—namely, the land use activity and the inventory flow.

Conclusions

The variability of CFs across all three regionalization levels provides an indication of the uncertainty linked to nonspatial CFs. Among other assumptions and value choices made throughout the study, the use of ecological borders over political boundaries was deemed more relevant to the interpretation of environmental issues related to specific functional ecosystem behaviors.  相似文献   
37.
Biomechanics and Modeling in Mechanobiology - This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg...  相似文献   
38.
Ma  Wen-Tao  Liu  Qi  Ning  Meng-Xia  Qi  Yu-Xu  Rehman  Saad  Chen  De-Kun 《BMC biotechnology》2019,19(1):1-11
Background

Tobacco stalk (TS), a major agricultural waste abundant in pectin, has resulted in concerns about the need for its reuse. The nicotine in TS is considered a chemical that is to\xic and hazardous to the environment.

Results

In this study, Bacillus tequilensis CAS-MEI-2-33 was isolated from cigar wrappers to produce alkaline pectinase using TS. Subsequently, the medium and fermentation conditions for the production of pectinase by B. tequilensis CAS-MEI-2-33 were optimized. The optimal fermentation period, pH of the initial fermentation medium, concentration of TS, and inoculum amount for B. tequilensis CAS-MEI-2-33 were 40 h, 40 g/L, 7.0, and 3%, respectively. Under optimal conditions, the pectinase activity was 1370 U/mL. Then, the enzymatic properties, such as the optimum pH, reaction temperature, temperature stability, and effects of metal ions, were studied. The optimal pH was determined to be 10.0, indicating that the enzyme was an alkaline pectinase. The optimal temperature was 40 °C, and pectinase activity was stable at 40 °C. The Ag+ metal ions were shown to remarkably promote enzyme activity. The pectinase was partly purified by ammonium sulfate precipitation, ion exchange chromatography, and Sephacryl S-100 chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and LC-MS/MS analyses were utilized to analyze the pectinase.

Conclusions

This study provided a new alkaline pectinase candidate and a new strategy for the use of TS.

  相似文献   
39.
A spectrofluorimetric method for the determination of eptifibatide is presented based on its native fluorescence. The type of solvent and the wavelength of maximum excitation and emission were carefully selected to optimize the experimental conditions. Under the specified experimental conditions, the linearities obtained between the emission intensity and the corresponding concentrations of eptifibatide were in the range 0.1–2.5 μg/ml for the calibration curve constructed for direct determination of eptifibatide in dosage form and 0.05–2.2 μg/ml for the calibration curve constructed in spiked human plasma with a good correlation coefficient (r > 0.99). The lower limit of quantification for the calibration curve constructed in human plasma was 0.05 μg/ml. Recovery results for eptifibatide in spiked plasma samples and in dosage form, represented as mean ± % RSD, were 95.17 ± 1.94 and 100.29 ± 1.33 respectively. The suggested procedures were validated according to the International Conference on Harmonization (ICH) guidelines for the direct determination of eptifibatide in its pure form and dosage form and United States Food and Drug Administration (US FDA) Guidance for Industry, Bioanalytical Method Validation for the assay of eptifibatide in human plasma.  相似文献   
40.
Protein content and amino acids composition of bee-pollens from major pollen floral sources in Al-Ahsa, Saudi Arabia were determined to investigate the nutritive value of pollen protein relative to requirements of honeybees and adult humans. The major pollen sources were alfalfa, date palm, rape, summer squash, and sunflower. Bee-pollens from alfalfa and date palm showed high content of crude protein and amino acid concentrations. Bee-pollen from sunflower had low content of those components. Eighteen amino acids were found in bee-pollens from the five major floral sources. The highest concentrations of individual amino acids valine, leucine, isoleucine, phenylalanine and proline were obtained from alfalfa bee-pollen; lysine, arginine, cysteine, tryptophan and tyrosine from date palm; methionine, histidine, glycine and alanine from summer squash; threonine, serine and glutamic acid from sunflower; and aspartic acid from rape bee-pollen. The amino acid composition obtained from sunflower bee-pollen showed the lowest concentrations of the essential amino acids: isoleucine, leucine, methionine, phenylalanine and valine. Apart from methionine, arginine and isoleucine, the essential amino acids of bee-pollen from alfalfa, date palm, summer squash and rape exceeded the honeybees’ requirements. Methionine was the limiting amino acid in bee-pollens from the five selected sources. Concentrations of essential amino acids in the tested bee-pollens were variable and significantly correlated to their botanical origin of pollen. Bee-pollens from alfalfa, date palm and summer squash was found to be rich source of protein and amino acids for bees and for humans.  相似文献   
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