Study of heterosis in single-cross hybrids of sunflower

    This study was conducted to estimate the genetic variability and heterosis of 40 F1 hybrids of sunflower for seed yield and its components over two seasons (summer and winter) in 2007 at Sennar Research Station Farm in central Sudan. The plant material consisted of 14 sunflower parents            (4 females and 10 males) and their 40 F1-hybrids. The experiment was arranged in a randomized complete block design with three replicates. The traits measured were days to 50% flowering, plant height, head diameter, number of seeds per head, one thousand seed weight and seed yield.  Hybrids showed high genetic variability for all traits studied than their parents which suggested some degree of hybrid vigor. The direction and magnitude of heterosis varied from cross to cross. Over two seasons, the average mid-parent heterosis in preferred direction and magnitude depicted that the hybrid SA2 x SR41 followed by SA3 x SR41 for days to flowering, SA1 x SR14 for plant height, SA2 x SR14 for head diameter, SA2 x SR13 followed by SA3 x SR13 for number of seeds per head, and SA3 x SR7 for one thousand seed weight. With regard to seed yield, the best hybrids with positive average heterosis were SA3 x SR41 (53.42%), SA4 x SR45 (52.75%), SA4 x SR1 (52.25%) and SA3 x SR10 (40.63%) which also combined with high seed yield of 1581 kg/ha, 1479 kg/ha, 1474 kg/ha, and 1457 kg/ha, respectively. These hybrids (involving the female line SA3 or SA4 and the male lines (SR10, SR13, SR41 and SR45) can be used in our breeding program in an attempt to develop local sunflower hybrid (s) with high seed yield and other important agronomic traits and for testing their yield potential and stability across locations and seasons.  أجريت هذه الدراسة بهدف تقدير التباين الوراثي و قوة الهجن  للإنتاجية ومكوناتها لأربعين هجين مفرد من محصول زهرة الشمس، نتجت من تهجين أربعة أمهات ذات عقم ذكرى سايتوبلازمى مع عشرة آباء معيدة للخصوبة. أجريت التجربة بمحطة بحوث سنار فى وسط السودان بالقطاع المروي لموسين             (صيف وشتاء2007). أستخدم تصميم القطاعات العشوائية الكاملة بثلاثة مكررات. كانت الصفات المدروسة هى عدد الايام حتى 50% إزهار، طول النبات، قطر القرص، عدد البذور بالقرص، وزن الآلف حبة، وانتاج البذور. أظهرت النتائج فروقات معنوية لكل الصفات في الموسمين مع تفوق الهجن وتباينها وراثياً مقارنة بالآباء. وفي التحليل المشترك لحساب قوة الهجين لكل الصفات كنسبة زيادة أو نقصان من متوسط الأبويين، ظهر أنّ الهــجينينSA2 x SR41  وSA3 x SR 41 هما الأفضل للإزهار والنضج المبكر، الهجين SA1 x SR14 لطول النبات، الهـجين SA2 x SR14 لقطر القرص ، الهجينين SA2 x SR13  و SA3 x SR13 لعدد البذور بالقرص، الهجين SA3 x SR7 لوزن الألف بذرة. أما بخصوص إنتاجية البذور أظهرت بعض الهجن نسبة قوة هجين موجبة SA3 x SR41 ) (53.42%، (52.73% ) SA4 x SR45،   SA4 x SR1   (52.25%)و SA3 x SR10 ((40.63% وإنتاجية بذور تقدر بـ 1581 كيلوجرام للهكتار، 1479 كيلوجرام للهكتار، 1474 كيلوجرام للهكتار و1459 كيلوجرام للهكتار علي التوالي. ويستنتج من هذه الدراسة ان الهجن التي يدخل في تركبيها الأم SA3 أو الأم SA4 مع الآباء SR41 ، SR45، SR13      و SR10 هى هجن متفوقة لإنتاجية البذور والصفات الأخرى ، ويمكن استخدام تلك الأمهات والآباء في تطوير هجن محلية مفردة من محصول الزهرة واختبار ثبات إنتاجيتها عبر المواسم والمواقع المختلفة

Factors Influencing Managers’ Decisions to Continue/Discontinue Capital Budgeting Projects

Normative decision theories stipulate that rational economic decisions (including investment decisions) are made based on the assessment of the expected outcomes. Accordingly, if available feedback information about an investment project indicates at any given point in time that the expected outcome would be negative, one would expect that such an investment project would be immediately terminated. This implies that any prior funds spent on an investment project that cannot be recovered (known as sunk costs) are considered irrelevant to the decision to terminate. However, the decision-making literature provides instances of entrapment or escalation where decision makers were influenced by sunk costs in their decisions.The psychology literature provides two basic explanations for this entrapment or escalation behaviour. The first explanation attributes the escalation behaviour to the notion of self-justification and asserts that a decision-maker who is associated with the initial decision to invest in a project will elect to commit additional resources to the investment project as a way to justify past decisions, even when the available information indicates that the project should be terminated. The second explanation is rooted in prospect theory, which postulates that decision-makers tend to evaluate choices as gains and losses in relation to a neutral reference point and that decision-makers are generally risk seeking when faced with possible losses. That is, a risk-seeking person would reject a certain loss in favour of a gamble with equal or even “lower” expected value. Thus, for commitment escalation, the theory asserts that decision makers would view sunk costs as a sure loss and they would prefer to engage in the escalation of prior commitments with the possibility of incurring greater losses or recovering past investments.Agency theory provides a third explanation for escalation of commitments. When a manager posses private information on the state of the project, abandoning a potentially failing project would reveal this state and adversely affect the manager’s reputation while further commitment of resources protects the manager’s reputation. This paper extends previous work on the escalation of commitment by considering the effects of two additional variables that usually constrain managers’ decisions. These variables are managers’ potential liability for committing additional resources to a potentially failing project, and the level of credibility of a project’s prospective information that the manager obtains.A between-subject experimental design is used where the three research variables (managers’ responsibility, potential liability, and credibility of information about the prospects of a hypothetical project) are factorially crossed to obtain eight sets of experimental conditions (a 2x2x2 ANOVA design)The results indicate significant main effects of initial responsibility, potential liability, and information credibility. In addition, there were significant two-way interaction effects between initial responsibility and potential liability and information credibility

Managers Motivational Antecedents To Support Activity-Based Costing Systems

The past three decades have witnessed a growing trend in using activity-based costing systems. Management and accounting research have identified management support as one of the focal points for successful implementation of such systems. However, little research has been done to study managers motivational antecedents to support activity-based costing systems in the Middle East as well as in the Asian countries. It is expected that the level of support differs from one culture to another. This paper addresses this issue in an experimental setting where 129 managers from two different cultures were asked to respond to judgmental decisions to support activity-based costing systems. Two models of the expectancy theory (the force model and the valence model) were used to measure the motivational support for activity-based costing systems. The authors hypothesized that these models provide better explanations than a chance model. The results of the regression analyses support the research hypotheses. However, the force model had a higher explanatory power than the valence model

Delineation of Water Bearing Formations in North Kordofan and West White Nile Area Using Vertical Electrical Sounding (VES) and Borehole Data

     The present study was conducted in 2012 to delineate the water bearing formations in North Kordofan and West White Nile areas. Vertical Electrical Soundings (VES) technique data and boreholes information from the study area were used in this study. IPI2Win and Freehand 9.02 software applications were used in this study. The former was used for VES data curves ID interpretation along single profile while the latter was used for drawing purpose. The results of the interpretation indicated that, the study area involves three aquifers: upper, lower and deep aquifers. The upper and lower aquifers locate in Bara Basin and west Kosti Basin whereas the deep aquifer locates in Kosti Basin. The thickness of the upper and lower aquifers together attains 150 m as in Umm Balagi and the thickness of the deep aquifer ranges between 25 to 60 m. The upper and lower aquifers are composed of similar rocks of coarse sand and gravels while the deep aquifer is mainly made up of medium sand. The static water table ranges between 20 m in the northwestern parts to more than 100 m in the southern parts. The mode of occurrence, rocks type, and hydraulic condition of the deep aquifer indicated that the aquifer is not a part of the lower aquifer as believed previously

Effect of Nitrophoska® and irrigation interval on root and sugar yield of sugar beet (Beta vulgaris L.), Gezira State, Sudan

Sugar beet is one of the promising crops in the Sudan due to its high root, sugar yield and by-products as an industrial crop. The crop is also a promising alternative energy crop for the production of ethanol. An experiment was conducted at the experimental Farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan, during seasons 2012/13 and 2013/14. The objective was to investigate the effects of irrigation intervals (7, 14 and 21 days) and Nitrophoska (NPK compound fertilizer) rates (0, 100, 150 and 200 kg/ha) on root and sugar yield of sugar beet (Ballade cultivar) under Gezira conditions. Split-plot design with three replicates was used. Irrigation intervals were allotted to the main plots and Nitrophoska rates to the subplots. Results showed that shortening irrigation intervals from 21 to 14 and 7 days increased root diameter, root weight and root and sugar yields in both seasons. In addition, Nitrophoska rate of 150 kg/ha substantially improved most of the studied root characters and sugar yield in both seasons. Depending on the results of this study, to obtain high root and sugar yields from sugar beet Ballade cultivar, it could be recommended  to apply 150 kg/ha of  Nitrophoska  and  irrigate every 7 to14 days.   بنجر السكر من المحاصيل الواعدة في السودان وذلك نسبة لإنتاجيته العالية من الجذور والسكر ومنتجاته كمحصول صناعي. بنجر السكر من محاصيل الطاقة البديلة الواعدة لإنتاج الإيثانول. أجريت التجربة في المزرعة التجريبية، كلية العلوم الزراعية، جامعة الجزيرة، وادمدني، السودان في الموسمين 2012/ 13 و 2013/14م على التوالي. الهدف من التجربة هو دراسة تأثير فترات الري (7 و14 و21 يوم) ومعدلات سماد النيتروفوسكا المركب (0 و100 و150 و200 كجم للهكتار) على إنتاجية الجذور والسكر لبنجر السكر (صنف بلدي) تحت ظروف الجزيرة. تم إستخدام تصميم القطع المنشقة بثلاث تكرارات. أوضحت النتائج أن تقليل فترات الري من 21 الي 14 و7 زاد قطر الجذر ووزن الجذر وإنتاجية الجذور والسكر في كلا الموسمين. زيادة معدلات سماد النيتروفوسكا المركب من 0 الى أكثر 150 كجم للهكتار حسن بشكل كبير أغلب الصفات المدروسة للجذر وإنتاجية السكر في كلا الموسمين. إعتماداً على نتائج هذه الدراسة للحصول على أعلى إنتاجية من الجذور والسكر لمحصول بنجر السكر نوصي بإضافة سماد النيتروفوسكا بمعدل 150 كجم/هكتار على أن يروى المحصول كل 7 إلى 14 يو

Seismic performance of reinforced concrete frames retrofitted using external superelastic shape memory alloy bars

Pre-1970s designed and built reinforced concrete frame structures are considered unsafe when subjected to seismic loads. Insufficient anchorage of the beam reinforcement in the beam-column joints of these structures is considered a main deficiency. Newly built frame structures are seismically designed for safety, where high inelastic deformations can occur under moderate to strong earthquakes. Minimizing these inelastic deformations makes the structure repairable. One way to minimize these residual deformations is by using smart materials such as superelastic shape memory alloys (SMAs). In this paper, the seismic performance of RC frames retrofitted using external superelastic SMA bars is investigated and compared to the behaviour of a regular steel RC frame structure. Nonlinear time history analysis is performed for a six storey RC frame structure located in a high seismic region. After performing the analysis, two retrofitted frames are assumed and analyzed at the load intensities causing failure of the steel RC frame. The performance of the retrofitted frames is compared to the steel RC frame in terms of the damage level, the Maximum Inter-Storey Drift (MID) ratio, Maximum Residual Inter-Storey Drift (MRID), Maximum Roof Drift Ratio (MRDR), Residual Roof Drift Ratio (RRDR), and the earthquake intensity at collapse. Analysis results show improved seismic performance for the two retrofitted frames as compared to the original steel RC frame. This improvement was represented by lower level of damage at the same earthquake intensity; small reduction (10–15%) in the MID and MRDR values; significant reduction (50–70%) in the MRID and RRDR; and increased seismic capacity

Effects of sowing date and intercropping on yield, yield components and oil content of sunflower and groundnut in a desert environment in northern Sudan

    The summer season in the Northern State, Sudan, is characterized by its limited field activities. The present and future expansion of agricultural production is targeted in desert plain soils away from the River Nile bank. This study was conducted during seasons 2014/15 and 2015/16 with the objectives of determining the effects of sowing date and intercropping system on yield, yield components and oil content of sunflower and groundnut. Split-plot design with randomized complete arrangement with four replicates was used. The main plots were assigned to the three sowing date namely: 1st June, 1st July and 1st August. The sub-plots were assigned to intercropping system: viz: sole cropped and intercropping (two rows of groundnut alternate with two rows of sunflower). The interaction between sowing date and intercropping had a significant (p ≤ 0.05) effect on yield component, total yield and oil content of both crops in both seasons. The highest seed yield was obtained by intercropped sunflower and sole groundnut for 1st June and 1st August, respectively. The highest oil content was attained by intercropped groundnut and sole sunflower, respectively, for 1st August.  First June sowing date resulted in the best land equivalent ratio in both seasons. Based on these results, to obtain high seed yield of high oil content, it could be recommended that 1st of June and 1st of August were optimum sowing dates for sunflower and groundnut, respectively in the desert environment of north Sudan. It was also recommended to intercrop sunflower with groundnut and sow them on the first of June for the highest LER.   النشاط الزراعي محدود جدا في الموسم الصيفي بالولاية الشمالية في السودان.  وأن التوسع الحالي والمستقبلي في الرقعة الزراعية يستهدف أراضي السهل الصحراوي والتروس العليا البعيدة عن حوض نهر النيل. نفذت هذه التجربة في المناخ الجاف علي تربة السهل الصحراوي في الولاية الشمالية في الموسم الصيفي 2014/15 و2015/16 بهدف تحديد أثر تاريخ الزراعة ونظام الزراعة البينية علي الإنتاجية ومكوناتها وكمية الزيت لمحصولي زهرة الشمس والفول السوداني. نظمت المعاملات إحصائيا باستخدام تصميم القطع المنشقة مع القطاعات العشوائية الكاملة بأربعة مكررات. حيث وضع في القطع الرئيسية ثلاثة تواريخ زراعة (1/6 و1/ 7 و1/8) وفي القطع الثانوية نظام الزراعة البينية: حيث زرع المحصول الواحد بمفرده والمحصولين مع بعض في زراعة بينية (صفان من الفول السوداني يَتناوبانِ مع صفين من زهرة الشمس). أظهرت النتائج أن التداخل بين تاريخ الزراعة والزراعة البينية كان له تأثير معنوي على مكونات الإنتاج والإنتاجية وكمية الزيت لكلا المحصولين في كلا الموسمين. أعلى إنتاجية بذور تحققت للزراعة البينية لزهرة الشمس ولمحصول الفول السوداني منفردا عند زراعتهما في تواريخ الأول من يونيو والأول من أغسطس على التوالي. أعلى نسبة زيت تحققت لمحصولي زهرة الشمس منفردا وللزراعة البينية للفول السوداني عند ما نفذت الزراعة بتاريخ الأول من أغسطس. قيمة مؤشر نسبة الأرض المكافئ أعلي من الرقم واحد في كل تواريخ الزراعة، وتاريخ أول يونيو أعطي أفضل مكافئ في الموسمين علي التوالي. للحصول على أعلى إنتاجية بذور ونسبة زيت لمحصولي زهرة الشمس والفول السوداني توصي الدراسة بأن الأول من يونيو  والأول  من أغسطس هي الأمثل لزراعة محصولي زهرة الشمس والفول السوداني علي التوالي في البيئة الصحراوية بشمال السودان, كما توصي أيضا بأن الزراعة البينية لزهرة الشمس والفول السوداني في أول يونيو هي الأفضل في استغلال الأرض. &nbsp

Forage yield of some legumes in monoculture and mixtures under irrigation in central Sudan

    The study was conducted during summer, autumn and winter seasons of 2014/15 and 2015/16 at the experimental farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan, to investigate the effect of mixing on forage yield of selected three legumes namely: cowpea (CP), black-eyed bean (BB) and lablab bean (LB) and their mixtures with three selected grasses, Sudan grass (SG), maize (MZ) and forage sorghum (Abu70). Legumes were grown in pure stand and mixed with grasses in 1:1 and 1:2 ratios. Treatment combinations were arranged in a randomized complete block design (RCBD) with four replications. The results showed that mixing significantly increased plant fresh weight, LAI, and fresh forage yield during most seasons and decreased number of branches per plant during different seasons. Land equivalent ratio mostly was greater than one. Based on the results of this study to obtain high forage yield, it was recommended to use seed combinations of 30 kg seeds/ha LB + 30 kg seed/ha MZ during autumn and winter and 30 kg seeds/ha BB + 30 kg seed/ha SG during summer season.     نفذت هذه الدراسة خلال صيف، خريف وشتاء 2014/2015 و2015/2016 بالمزرعة التجريبية لكلية العلوم الزراعية، جامعة الجزيرة، السودان. تهدف هذه الدراسة لتقييم أثر الخلط علي إنتاجية المحاصيل البقولية المختارة وهي اللوبيا الحلو واللوبيا البيضاء واللوبيا العفن ومخاليطها مع المحاصيل النجيلية حشيشة السودان، أبوسبعين والذرة الشامية تحت ظروف الري في أواسط السودان. زرعت المحاصيل البقولية منفرده وفي مخاليط بنسبة 1 : 1 و 1 : 2. تم استخدام تصميم القطاعات العشوائية الكاملة بأربعة مكررات. الخلط أدى إلى زيادة معنوية لكل من  وزن النبات الرطب، دليل مساحة الأوراق وإنتاجية العلف الأخضر خلال معظم المواسم بينما أدى الخلط إلى نقصان عدد الأفرع في مختلف المواسم. كانت قيم نسبة مكافئ الأرض في أغلب المواسم  أعلى من الواحد الصحيح. بناءً على نتائج هذه الدراسة ولتحقيق إنتاجية أعلاف عالية نوصي بزراعة المحاصيل البقولية في مخاليط بنسبة خلط 30 كجم بذور/هكتار لوبيا عفن + 30 كجم بذور/هكتار ذرة شامية خلال فصلي الخريف والشتاء وبنسبة 30 كجم بذور/هكتار لوبيا حلو + 30 كجم بذور/هكتار حشيشة السودان خلال فصل الصيف.                         &nbsp

Blockage Prediction for Mobile UE in RIS-assisted Wireless Networks: A Deep Learning Approach

Due to significant blockage conditions in wireless networks, transmitted signals may considerably degrade before reaching the receiver. The reliability of the transmitted signals, therefore, may be critically problematic due to blockages between the communicating nodes. Thanks to the ability of Reconfigurable Intelligent Surfaces (RISs) to reflect the incident signals with different reflection angles, this may counter the blockage effect by optimally reflecting the transmit signals to receiving nodes, hence, improving the wireless network's performance. With this motivation, this paper formulates a RIS-aided wireless communication problem from a base station (BS) to a mobile user equipment (UE). The BS is equipped with an RGB camera. We use the RGB camera at the BS and the RIS panel to improve the system's performance while considering signal propagating through multiple paths and the Doppler spread for the mobile UE. First, the RGB camera is used to detect the presence of the UE with no blockage. When unsuccessful, the RIS-assisted gain takes over and is then used to detect if the UE is either "present but blocked" or "absent". The problem is determined as a ternary classification problem with the goal of maximizing the probability of UE communication blockage detection. We find the optimal solution for the probability of predicting the blockage status for a given RGB image and RIS-assisted data rate using a deep neural learning model. We employ the residual network 18-layer neural network model to find this optimal probability of blockage prediction. Extensive simulation results reveal that our proposed RIS panel-assisted model enhances the accuracy of maximization of the blockage prediction probability problem by over 38\% compared to the baseline scheme