Embryoid induction and plantlet regeneration from leaf segments of sugarcane (Saccharum officinarum L.)

     Sugarcane (Saccharum officinarum L.) is an economically important crop in Sudan for domestic consumption and export. It is the first and essential source for production of high purity sugar. Tissue culture techniques can be used for in vitro conservation of sugarcane (Taylor and Dukic, 1993) and mass propagation of elite cultivars of crop species. Moreover, it was used for production of pathogen-free planting material from infected mother plants. Variability induced in vitro can furnish a base for improvement of vegetatively propagated crops including sugarcane. Different tissue culture techniques were applied successfully to sugarcane propagation and plant regeneration through organogenesis of shoot meristem (Nadar and Heinz, 1977; Ho and Vasil, 1983a), cell suspension cultures (Ho and Vasil, 1983b, Aftab et al., 1996) and protoplast cultures ( Liu, 1994). Cell suspen - Sion cultures were also used for cytological, pathological (Peros and Lombard, 1992), biochemical and physiological investigations of sugarcane (Heinz et al., 1977).      This study was initiated, during 1998-2000, to investigate the effect of 2,4-D on induction of embryogenic callus from leaf explants of sugarcane and regeneration of somatic embryos on different concen-trations of Murashige and Skoog (1962) medium (MS)

Role of Laser Produced Silver Nanoparticles in Reversing Antibiotic Resistance in Some MultidrugResistant Pathogenic Bacteria

Silver nanoparticles (Ag NPs) were produced through nanosecond laser in deionized water. These nanoparticles were characterized by UV–VIS spectrometer and transmission electron microscopy. VITEK®2 compact system was used to identify Escherichia coli (ESBL strain) and Staphylococcus aureus (MRSA strain) as multidrug-resistance (MDR) bacteria. The antibacterial activity of Ag NPs, ampicillin (AMP), and their combinations was tested against both bacterial isolates through standard microbiological culturing techniques. Our data show that both of E. coli and S. aureus were highly resistant to AMP. Ag NPs alone reduced growth in both bacterial isolates considerably. Growth declined drastically in both bacteria when AMP was used in combination with Ag NPs. The minimal inhibitory concentration of combined agents for E. coli was 20 µg/ml Ag NPs + 1 mg AMP/ml and for S. aureus was 10 µg/ml Ag NPs + 1 mg AMP/ml. The results show that the Ag NPs have great potentials in enhancing the antimicrobial activities of drugs that used to be ineffective against MDR bacteria. Administering combinations of antibiotic(s) with AgNPs may help in treating patients suffering from infections caused by MDR bacteria. Further in vivo and in vitro investigations are required to evaluate the side effects of these combinations

The Accumulation Risk of Heavy Metals in Vegetables which Grown in Contaminated Soil

أجريت الدراسة الحالية لتقييم الحركة، التراكم الأحيائي ونقل المعادن الثقيلة (الحديد، الزنك، الكادميوم، النيكل، الكروم، المنجنيز، النحاس والرصاص) من التربة الملوثة إلى أنسجة الجذور ومن الجذور إلى الأجزاء الهوائية عن طريق حساب معامل التركيز الأحيائي وعامل الانتقال. جمعت عينات التربة والعينات النباتية لثمانية أنواع من الخضروات خلال موسم الصيف 2019 من أربعة مواقع مختلفة تقع في وادي الأرج ، محافظة الطائف ، المملكة العربية السعودية. بشكل عام ، سجلت عينات التربة المأخذوه من الموقع الثالث والرابع قيمًا مرتفعة من المعادن الثقيلة مقارنةً بالموقعين الأول والثاني. أظهرت التربة من الموقع الرابع أعلى تركيز من Mn و Ni و Cr و Pb و Cu و Cd بلغ 31.63 و 14.05 و 13.56 و 22.79 و 31.02 و 2.98 ملجم / كجم تربة جافة على التوالي ، بينما أظهرت التربة من الموقع الثالث أعلى تركيز للزنك. أشارت البيانات من الدراسة إلى أنه يمكن التعرف على نباتات الخس، النعناع، الشبث، الخيار، الفلفل والقرع التي نمت في مواقع الدراسة على أنها مناسبة للاستهلاك البشري، فهذه الخضروات الستة تراكم المعادن الثقيلة في أعضائها بكميات مقبولة بأقل من المستويات المسموح بها لمنظمة الأغذية والزراعة للأمم المتحدة. بخلاف ذلك، وجد أن تركيزات المعادن الثقيلة في نبات الطماطم ونبات الباذنجان أعلى من الحدود المسموح بها لمنظمة الأغذية والزراعة. الطماطم والباذنجان أيضاً أظهرت قيم عامل التركيز الأحيائي  مرتفعة لمعظم المعادن الثقيلة المقاسة. بالنسبة للطماطم كان معامل التركيز الأحيائي لكل من الكادميوم، النحاس، الحديد، الرصاص، المنجنيز، الزنك، الكروم والنيكل 27.250، 42.150، ،1.023، ND، 4.649، 0.459، 5.926 و 29.409 على التوالي. بينما كان في الباذنجان 21.333، ND، 2.360، 0.170، 3.113، 0.623، ND و 50.318 على التوالي.لتجنب الآثار الضارة لتراكم المعادن الثقيلة على صحة الإنسان ، يجب مراعاة الفحص المستمر للمحاصيل المزروعة في الترب الملوثة بالمعادن الثقيلة. أشارت البيانات من الدراسة إلى أنه يمكن التعرف على نباتات الخس، النعناع، الشبث، الخيار، الفلفل والقرع التي نمت في مواقع الدراسة على أنها مناسبة للاستهلاك البشري، فهذه الخضروات الستة تراكم المعادن الثقيلة في أعضائها بكميات مقبولة بأقل من المستويات المسموح بها لمنظمة الأغذية والزراعة. بخلاف ذلك، وجد أن تركيزات المعادن الثقيلة في نبات الطماطم ونبات الباذنجان أعلى من الحدود المسموح بها لمنظمة الأغذية والزراعة. الطماطم والباذنجان أيضاً أظهرت قيم عامل التركيز الأحيائي  مرتفعة لمعظم المعادن الثقيلة المقاسة. بالنسبة للطماطم قيم عامل التركيز الأحيائي لكل من الكادميوم، النحاس، الحديد، الرصاص، المنجنيز، الزنك، الكروم والنيكل كانت 27.250، 42.150، ،1.023، 0.000، 4.649، 0.459، 5.926 و 29.409 على التوالي. بينما كانت في الباذنجان 21.333، 0.000، 2.360، 0.170، 3.113، 0.623، 0.000 و 50.318 على التوالي. لا ينصح بزراعة الطماطم والباذنجان في التربة الملوثة بالمعادن الثقيلة بدون معالجة التربة مع ضرورة إجراء تحليل دوري للأجزاء الصالحة للأكل من الخضروات المزروعة في التربة الملوثة بالمعادن الثقيلة لمراقبة هذه المواد في النظام الغذائي البشري وتجنب آثاره الضارة على صحة الإنسان.The present study has been carried out to estimate heavy metals mobility, bioconcentration and transfer from polluted soil to roots tissues and from roots tissues to aerial parts using bioconcentration factor and translocation factor. Soil samples and the biomass of the eight vegetable species have been collected during summer season, 2019 from four different sites in Wadi Al-Arg, Taif Governorate, KSA. In general, heavy metals content of soil samples in site III and IV have recorded elevated values compared with those of site I and II. The soil from site IV has shown the highest concentration of Mn, Ni, Cr, Pb, Cu, and Cd amounted 31.63, 14.05, 13.56, 22.79, 31.02 and 2.98 mg/kg dry soil respectively, while the soil from site III has shown the highest concentration of Zn. The data referred to the fact that Mentha longifolia, Cucumis sativus, Capsicum annuum, Lactuca sativa Cucurbita pepo, and Anethum graveolens that grown in sites of investigation could be recognized as suitable for human consumption. These six vegetables could accumulate the measured heavy metals in their tissues with acceptable quantities, less than the permissible levels of Food and Agriculture Organization of the United Nations (FAO). Otherwise, heavy metal concentrations in Solanum lycopersicum and Solanum melongena have been found to be higher than permissible limits of FAO. Both plants also have shown elevated bioconcentration factors values for most of measured heavy metals. For S. lycopersicum the bioconcentration factor values of Fe, Cd, Cu, Pb, Cr, Mn, Ni, and Zn have been found to be 42.150, 27.250, 1.023, ND, 5.926, 4.649, 29.409, and 0.459 respectively. While for S. melongena, they have been 2.360, 21.333, ND, 0.170, ND, 3.113, 50.318, and 0.623, respectively. To avoid the harmful effects of the heavy metals accumulation on human health, consideration should be given to the constant examination to the edible parts of the vegetables grown in heavy metals contaminated soil

Emerging Wireless LAN Mobility Protocols

Wireless LANs have become the dominant device over the last few years. The initial goal was to remove cables from the network, but with the fast pace in technological development wireless networks became popular not only inside organizations, but also as hotspots throughout cities. Major governments are encouraging the institutes to deploy wireless LANs due to the increase in number of Internet users and online applications. Over the past few years, wireless LANs have grown tremendously from a small network to the enterprise level, installed across buildings and organizations to provide mobility. In addition, the mobility and convenience of wireless has been improved by the advanced throughput and range performance available in today’s products, extending the reach of wireless LANs to a broad array of applications. This has led researchers to work on protocols which provide smooth mobility to the mobile nodes. It has opened the door to develop protocols which can be used to provide mobility within an organization and between organizations. This paper discusses the existing mobility architecture and reviews some of the emerging wireless mobility protocols—specifically host-based and network-based mobility—with a focus on local and global mobility. It also serves as part of the ongoing research for the PhD program in the department of Computer Science at the Universiti Teknologi Malaysia

Microbial Contamination of Date Rutab Collected from the Markets of Al-Hofuf City in Saudi Arabia

The microbial contamination of 60 samples from six date cultivars in the rutab stage purchased from different retail outlets in AL-Hofuf City, Saudi Arabia was studied. All samples were found contaminated with aerobic mesophilic bacteria at loads in the order 102 to 105 cfu/cm2 with some significant differences among varieties that can be attributed to differences in the weather conditions during rutab season. Also all samples, except only one, were contaminated with molds and yeasts at loads in the order 102 to 103 cfu/cm2. Potentially pathogenic Staphylococcus aureus was detected in 57 samples and A. flavus/parasiticus in 13 samples, while coliforms were detected in 39 samples

Effects of mist fractions on heat transfer characteristics in a rotating roughened cooling passage

This paper investigates the effects of the mist fractions on heat transfer characteristics applied on a rotating U-channel with inclined ribs at an angle of 45°. This study has been conducted on five different mist percentages from 1 to 5 with a 1% increment at each step, and all of the cases have been investigated for Reynolds number values of 5000, 10000, 25000 and 40000. The numerical results obtained from the application of RNG k-ε turbulence model with enhanced-wall function were in good agreement with the experimental data of the smooth and ribbed channels both with and without mist addition. Results also demonstrated a 300% increase in the flow temperature difference and a noticeable increase in Nusselt number at each bend region and at the downstream of the leading edge around 25% and 110% respectively, at high mist fraction (5%); when compared with the case where only air was used. With %5 mist addition, the convective efficiency also reaches approximately 69%

Biomimetic Based EEG Learning for Robotics Complex Grasping and Dexterous Manipulation

There have been tremendous efforts to understand the biological nature of human grasping, in such a way that it can be learned and copied to prosthesis–robotics and dextrous grasping applications. Several biomimetic methods and techniques have been adopted, hence applied to analytically comprehend ways human performs grasping to duplicate human knowledge. A major topic for further study, is related to decoding the resulting EEG brainwaves during motorizing of fingers and moving parts. To accomplish this, there are a number of phases that are performed, including recording, pre-processing, filtration, and understanding of the waves. However, there are two important phases that have received substantial research attentions. The classification and decoding, of such massive and complex brain waves, as they are two important steps towards understanding patterns during grasping. In this respect, the fundamental objective of this research is to demonstrate how to employ advanced pattern recognition methods, like fuzzy c-mean clustering for understanding resulting EEG brain waves, in such a way to control a prosthesis or robotic hand, while relying sets of detected EEG brainwaves. There are a number of decoding and classification methods and techniques, however we shall look into fuzzy based clustering blended with principle component analysis (PAC) technique to help for the decoding mechanism. EEG brainwaves during a grasping and manipulation have been used for this analysis. This involves, movement of almost five fingers during a grasping defined task. The study has found that, it is not a straight forward task to decode all human fingers motions, as due to the complexity of grasping tasks. However, the adopted analysis was able to classify and identify the different narrowly performed and related fundamental events during a simple grasping task

Ownership structure’s effect on financial performance : an empirical analysis of Jordanian listed firms

This study aims to examine the impact of the ownership structure on firm performance in the Jordan. This study employed the multiple-regression model and fixed regression effect to analyse the data. The sample included all Jordanian first market firms listed on the Amman Stock Exchange (ASE) from 2012 to 2018. The paper’s findings reveal a positive and significant relationship between institutional ownership and both accounting measure Return on Assets (ROA) and market measure Tobin’s Q (TQ). Other ownership structure types, such as concentration of ownership, also affect ROA and TQ. While managerial ownership shows a negative relationship with ROA, but there is no association with TQ. This study has broad and comprehensive practical implications that are good for policymakers. On the one hand, it adds to the debate on agency theory from the ownership structure and firm’s performance relationship. On the other hand, it helps the Jordanian Government formulate policies and regulations to strengthen corporate governance (CG), which increases the interests of all stakeholders in the Jordanian market