30 research outputs found
Optical properties of radially-polarised twisted light
We show that, in general, any type of radially-polarised paraxial twisted
optical mode carries only an axial total optical angular momentum (AM) where is the winding number and
is a constant. This mode, however, is shown to have zero spin angular momentum
(SAM), so it is endowed only with orbital angular momentum (OAM) and no SAM.
The helicity is found to be proportional to , hence radially-polarised
modes display chirality. When applied to a Laguerre-Gaussian (LG) mode our
treatment leads to a total helicity equal to , where
is the action constant. The factor , depends on
the sign, not the magnitude of and so the result holds for any
radially-polarised LG mode however large the magnitude of its winding number
is. The magnitude of the action constant and hence the
helicity are diminished for all such LG modes of large beam waist .Comment: 4 figure
Diet Selection by Goats on Rangeland of North Kordofan State, Sudan
This study was conducted at El Demokeya forest, North Kordofan State, Sudan. The objective was to evaluate goat diet botanical composition as an indicator for pasture quality. Bite counts were obtained from seven goats in protected and open rangeland sites. Percent plant cover in the two range sites were 81.9% and 87.5% respectively. Density was 260.9 and 181.9 plants / m2 respectively (P \u3c 0.05). At flowering, goat diet contained 10.8% ± 1.12 and 11.8% ± 5.94 CP in protected and open sites respectively. At seed set CP% was 8.1 ± 1.32 and 8.2 ± 3.01 respectively (P \u3e 0.01). Diet CP% was higher in diet than in forage biomass vegetation. At flowering, in protected range Acacia senegal (26.6%), Echinocloa colonum (11.34%) and Zaleya pentandra (9.08%) were the browse, grasses and forbs most selected, respectively. In the open range site Acacia senegal was 22.58%, Eragrostis tremula 13.78% and Zaleya pentandra 11.05% of the diet. At seed set, in the protected range site, the diet contained 18.36% Justica kotschyi, 15.02% Acacia senegal and 4.28% Eragrostis tremula.While in open range site Eragrostis tremula was 52.92%, Acacia senegal 25.58% and Chrozophora brocchiana 1.62%. Grasses and forbs with highest relative preference indeces (RPI) at flowering in protected range site were Cenchrus biflorus (RPI=2.05) and Justica kotschyi (RPI=7.93). In open range site the grass and forb with highest RPI were Echinocloa colonum (RPI=1.17) and Zornia glochidiata (RPI=6.7) respectively. Diet botanical composition is an indicator of plant preference and is useful in selecting plants for reseeding of deteriorated range and in identifying key species for range management
On the application of proper orthogonal decomposition (POD) for in-cylinder flow analysis
Proper orthogonal decomposition (POD) is a coherent structure identification technique based on either measured or computed data sets. Recently, POD has been adopted for the analysis of the in-cylinder flows inside internal combustion engines. In this study, stereoscopic particle image velocimetry (Stereo-PIV) measurements were carried out at the central vertical tumble plane inside an engine cylinder to acquire the velocity vector fields for the in-cylinder flow under different experimental conditions. Afterwards, the POD analysis were performed firstly on synthetic velocity vector fields with known characteristics in order to extract some fundamental properties of the POD technique. These data were used to reveal how the physical properties of coherent structures were captured and distributed among the POD modes, in addition to illustrate the difference between subtracting and non-subtracting the ensemble average prior to conducting POD on datasets. Moreover, two case studies for the in-cylinder flow at different valve lifts and different pressure differences across the air intake valves were presented and discussed as the effect of both valve lifts and pressure difference have not been investigated before using phase-invariant POD analysis. The results demonstrated that for repeatable flow pattern, only the first mode was sufficient to reconstruct the physical properties of the flow. Furthermore, POD analysis confirmed the negligible effect of pressure difference and subsequently the effect of engine speed on flow structures
Nutritional composition, extraction, and utilization of wheat germ oil: A review
Wheat germ is a by-product of wheat milling from which wheat germ oil (WGO) can be obtained using different techniques. For a better quality WGO, techniques such supercritical fluid fractionation, molecular distillation, and other innovative methods can be adopted. WGO is composed of nonpolar lipids, glycolipids, phospholipids, alcohols, esters, alkene, aldehydes, tocopherols, n-alkanols, sterols, 4-methyl sterols, triterpenols, hydrocarbons, pigments, and volatile components. The most abundant WGO fatty acid is linoleic acid which composes 42–59% of total triglycerides followed by palmitic (16:0) and oleic acids (18:1). The stearic acid, a saturated fatty acid, is usually less than 2%. WGO is rich in tocopherols particularly vitamin E. It contains a-tocopherol and b-tocopherol which gives various health benefits to it. It is being used in medicine, cosmetic, agricultural, and food industry. Some of its applications include production of vitamins and food supplements, animal feed and biological insect control and for treating circulatory/cardiac disorders and weaknesses. More studies are required for producing better quality WGO such as application of more innovative and optimized techniques that can increase its health benefits and hence utilization. More mechanistic approaches for extraction, evaluation, and utilization of WGO can help in making this by-product of wheat processing more valuable
The Khartoum revolving drug fund: an evaluation of sustainability, quality and access
sch_iihunpub3382unpu
Evaluation of nutritional status of foreign students at King Saud University, Kingdom of Saudi Arabia
Isolation and Identification of Streptomyces spp. from Desert and Savanna Soils in Sudan
The purpose of this study was to investigate streptomycete populations in desert and savanna ecozones in Sudan and to identify species based on 16S rRNA gene sequences. A total of 49 different Streptomyces phenotypes (22 from sites representing the desert and semi-desert ecozone; 27 representing the savanna ecozone) have been included in the study. The isolates were characterized phenotypically and confirmed using 16S rRNA gene sequence analysis. The two ecozones showed both similarities and uniqueness in the types of isolates. The shared species were in cluster 1 (Streptomyces (S.) werraensis), cluster 2 (Streptomyces sp.), cluster 3 (S. griseomycini-like), and cluster 7 (S. rochei). The desert ecozone revealed unique species in cluster 9 (Streptomyces sp.) and cluster 10 (S. griseomycini). Whereas, the savanna ecozone revealed unique species in cluster 4 (Streptomyces sp.), cluster 5 (S. albogriseolus/ S. griseoincarnatus), cluster 6 (S. djakartensis), and cluster 8 (Streptomyces sp.). Streptomycetes are widely distributed in both desert and the savanna ecozones and many of these require full descriptions. Extending knowledge on Streptomyces communities and their dynamics in different ecological zones and their potential antibiotic production is needed
Changes in protein nutritional quality as affected by processing of millet supplemented with Moringa seed flour
Pearl millet flour was supplemented with 5%, 10% and 15% defatted Moringa seeds flour (DMSF). Raw and supplemented flour were fermented and/or cooked for 0, 8 and 16 h. Changes in protein content and digestibility and amino acid compositions and scores of the samples were investigated. Supplementation of raw flour increased significantly (p ⩽ 0.05) the protein content and digestibility. Further increase in protein content and digestibility was observed in the fermented dough of raw flour and higher values were obtained after cooking of 16 h-fermented dough (p ⩽ 0.05). Amino acids were increased significantly (p ⩽ 0.05) with supplementation level. Cooking of the flour supplemented with 10% DMSF lowered both essential and non-essential amino acids with lysine and glycine reduced to 25.68 and 12.09 mg/100 g, respectively. Fermentation for 16 h increased amino acids except isoleucine, phenylalanine, arginine, serine and proline compared to cooked composite flour. All amino acids were significantly (p ⩽ 0.05) increased after cooking of 16 h-fermented dough. The chemical scores of the essential amino acids of the flour were fluctuated after supplementation. The majority of the amino acids scores were decreased after cooking of 10% DMSF fermented dough except histidine, lysine and threonine
International Journal of Multidisciplinary and Current Research Assessment the Effect of Omega-3 Fatty Acid Supplementation in Sudanese patients with Sickle Cell Anemia; Khartoum, Sudan
Abstract Background: Sickle cell disease (SCD) is a group of genetic blood disorders characterized by a single point mutation i