217 research outputs found

    Quantum Double Dot as Quantum Computer Unit

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    In this work, we have investigated the exchange interaction of two electrons in double lateral quantum dot (which is the base of quantum gate) under effect of external magnetic field, electric field and inter dot distance between double dots. From similarity between double quantum dots and molecule, we have used molecular physics approaches (Hitler London and Hund Mullikan approximation method) to investigate our system. We also show the magnetization behavior as function of magnetic field

    Modeling and simulation of a 3-ф induction motor based on two types of WFA

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    This paper has been proposed to simulate the transient model of 3-Ф cage rotor induction motor based on winding function approach (WFA). According to this method the motor is assumed to be consist of an electrical circuits on both stator and rotor. The magneto motive forces (MMF) that have been generated by these circuits play a role for coupling them together. Then mutual and self-inductances will be easily computed using WFA. Two types of WFA have been used to build and simulate the model of the induction motor. In the one part type, it’s assumed that the coupling MMF between stator and rotor have a non-sinusoidal shapes according to the actual windings distribution over the motor slots. While in second part type the generated MMF in are assumed to have sinusoidal waveform. The suggested models may be used to simulate the dynamic as well as steady state performance of a faulty and non-faulty motor. A simulation of the suggested models that consists of m-rotor bars and n-stator phases multiple coupled circuit-based has been performed using matlab m.file and the results of the motor current have been proved in its nonlinear way by using WFA

    DNA minor groove binders-inspired by nature

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    The synthesis and biological activity of a variety of analogues to the naturally occurring anti-bacterial and anti-fungal Distamycin A were explored by a number of authors. These compounds were subject to a large array of assays. Some of these compounds showed high activity against a range of Gram-positive, Gram-negative bacteria as well as fungi. To explore the anti-parasitic activity of this class of compounds, specific modifications had to be made. A number of these compounds proved to be active against Trypanosoma brucei. The binding of a number of these compounds to short sequences of DNA were also examined using footprinting assays as well as NMR spectroscopy. Computer modelling was employed on selected compounds to understand the way these compounds bind to specific DNA sequences. A large number of variations were made to the standard structure of Distamycin. These changes involved the replacement of the pyrrole moieties as well as the head and tail groups with a number of heterocyclic compounds. Some of these MGBs were also investigated for their capability for the treatment of cancer and in particular lung cancer

    Biomarker Significance of Serum CXCL8, CXCL10 and CXCL16 in Breast Tumors of Iraqi Patients

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    قيمت الاهمية الواسم-حياتية لثلاث من الحركيات الكيميائية (CXCL8 وCXCL10 وCXCL16) في مصول 45 من مريضات سرطان الثدي و28 من مريضات ورم الثدي الحميد و20 من نساء السيطرة. واعتمدت المرحلة السريرية وتعبير الورم لمستقبلات Estrogen وProgesterone وعامل النمو الشري HER-2 في هذا التقييم. اظهرت النتائج زيادة معنوية في متوسط CXCL8 وCXCL10 وCXCL16 لمريضات سرطان الثدي ومريضات ورم الثدي الحميد مقارنة بالسيطرة (CXCL8: 47.3 و25.7 مقابل 15.0؛ CXCL10: 37.6 و30.7 مقابل 13.1؛ CXCL16: 27.9 و25.2 مقابل 19.2 بيكوغرام/مل، على التوالي). وكانت زيادة مستوى CXCL8 وCXCL16 اكثر وضوحا في المريضات ثلاثية-سالبة التعبير والموجبة للمستقبل HER-2، على التوالي. اظهر تحليل الانحدار اللوجستي الثنائي اهمية CXCL8 كعامل تنبؤي لسرطان الثدي وان ذلك اكثر وصفا في المريضات ثلاثية سالبة التعبير. وفضلا عن ذلك فقد اظهر تحليل خصائص المستقبل التشغيلية باحتلال CXCL8 مساحة تحت المنحنى قدرها 0.988 في مريضات سرطان الثدي. يمكن الاستنتاج بان CXCL8 ذو اهمية لواسم - حياتي لسرطان الثدي خصوصا عند الاخذ بنظر الاعتبار تعبير الورم لمستقبلات Estrogen وProgesterone وعامل النمو الشري HER-2. وفي هذا الصدد، فان الدراسة تقترح الاهمية التنبؤية للحركي الكيميائي-8 في تطور سرطان الثدي لدى المريضات ثلاثية سالبة التعبير.The biomarker significance of three chemokines (CXCL8, CXCL10 and CXCL16) was evaluated in sera of 45 breast cancer (BC) and 28 benign breast lesion (BBL) patients, as well as 20 control women. Clinical stage and tumor expression of estrogen (ER), progesterone (PgR) and human epidermal growth factor receptor-2 (HER-2) receptors were considered in this evaluation. The results demonstrated that CXCL8, CXCL10 and CXCL16 showed a significant increased median in BC and BBL patients compared to control (CXCL8: 47.3 and 25.7 vs. 15.0; CXCL10: 37.6 and 30.7 vs. 13.1; CXCL16; 27.9 and 25.2 vs. 19.2 pg/ml, respectively). The increased levels of CXCL8 and CXCL16 were more pronounced in triple-negative and HER-2 positive patients, respectively. Binary logistic regression analysis revealed that CXCL8 was a significant predictor of BC, and such prediction was more depicted in triple-negative patients. The receiver operating characteristic analysis also revealed that CXCL8 recorded an area under curve of 0.998 in BC patients. In conclusion, CXCL8 is a potential biomarker for BC, especially when ER, PgR and HER-2 expression is considered. In this context, the predictive significance of CXCL8 in influencing BC progression is suggested in triple-negative patients

    Performance investigation of stand-alone induction generator based on STATCOM for wind power application

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    Self-Excited induction generators (SEIG) display a low voltage and frequency regulation due to variable applied load and input rotation speed. Current work presents a simulation and performance analysis of a three-phase wind-driven, SEIG connect to a three-phase load. In addition, an investigation of the dynamic operation of the induction generator from starting steady state until no-load operation. It is assumed that the input mechanical power is constant where the rotor of the SEIG rotates at a constant speed. The value of the excitation capacitance which is necessary to the operation of the induction generator also computed to ensure a smooth and self-excitation starting. The output voltage of the generator is adjusted by varying the reactive power injected by STATCOM. A 3-phase IGBT voltage source inverter with a fuel cell input supply is connected as STATCOM which is used to compensate for the reduction in the supply voltage and its frequency due to variation occurred in the applied loads. This work includes introducing a neuro-fuzzyy logic controller to enhance the performance of the SEIG by regulation the generated voltage and frequency The dynamic model of SEIG with STATCOM and loads are implemented using MATLAB/SIMULIN

    Sponge media drying using a swirling fluidized bed dryer

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    Surface preparation today has seen the introduction of sponge media as an alternative product against the traditionally used abrasive materials. Being soft and elastic, the sponge media reduces air borne emission significantly during surface preparation with capability to be re-used. However the environmental conditions limit the sponge media usage whereby wet surroundings prohibit the re-use of the sponge without being dried properly. This study proposes the swirling fluidized bed dryer as a novel drying technique for sponge media. Batch experiments were conducted to study the bed’s hydrodynamics followed by drying studies for three bed loadings of 0.5 kg, 0.75 kg and 1.0 kg at three drying temperatures of 80°C, 90°C and 100°C. It was found that, minimum fluidization velocities for the wet sponge particles were found to be 1.342, 1.361 and 1.382 m/s with minimum swirling velocities of 1.400, 1.469 and 1.526 m/s. Drying times were recorded between 6 to 16 minutes depending on bed loading and drying temperature. Smaller bed weights exhibits faster drying with constant-rate drying period while higher drying temperature and larger bed load resulted in falling-rate drying period. Thin layer modelling for the falling-rate region indicates that Verma et. al model provides the best fit for the present experimental data with coefficient of determination, R2 = 0.98773, root mean square error, RMSE = 0.05048, residuals = 0.3442 and reduced chi-square, χ2 = 0.00254. The effective diffusivity, Deff, for 0.5 kg bed load was found to be 3.454 x 10-9 m2/s and 1.751 x 10-9 m2/s for 0.75 kg bed load. In conclusion, SFBD was found to be a viable and efficient method in drying of sponge media for various industrial applications particularly surface preparation

    The Effect of Teaching an Advanced Unit from the Geograghy Textbook Based on Economic Values on Developing Consumer Awareness among Basic Eighth Grade Students in Jordan أثر تدريس وحدة مطورة من كتاب الجغرافيا قائمة على القيم الاقتصادية في تنمية الوعي الاستهلاكي لدى طلاب الصف الثامن الأساسي في الأردن

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    Abstract: This study aimed at discovering the effect of developed unit from the geograghy textbook, based on economic values on developing consumer awareness among basic eighth grade students in Jordan.The sample of the study consisted of (66) students who were purposely selected from the Judge Eyas Basic School for Boys in the Directorate of Education in Sahab District, and were randomly divided into an experimental group of (33) students and a control group consisting of (33) students. The third unit, Natural Resources of the 8th grade geography textbook were developed in light of economic values system, and the consumer awareness scale were built, the results showed that there was an effect of the developed unit from the geograghy textbook based on economic values on developing the consumer awareness in Jordan. The study recommended the adoption of the developed unit in the textbook of geography to teach students at the eighth grade. ملخص: هدفت هذه الدراسة إلى الكشف عن أثر تدريس وحدة مطورة من كتاب الجغرافيا قائمة على القيم الاقتصادية في تنمية الوعي الاستهلاكي لدى الطلاب الصف الثامن الأساسي في الأردن, وتكونت عينة الدراسة من (66) طالبًا جرى اختيارهم قصديًا من مدرسة القاضي إياس الأساسية للبنين التابعة لمديرية التربية والتعليم في لواء سحاب, وجرى تقسيمهم عشوائيًا إلى مجموعة تجريبية مكونة من (33) طالبًا, ومجموعة ضابطة تكونت من (33) طالبًا, وطورت الوحدة الثالثة الموارد الطبيعية من كتاب الجغرافيا للصف الثامن, و تم بناء مقياس الوعي الاستهلاكي, أظهرت النتائج وجود أثر للوحدة المطورة من كتاب الجغرافيا للصف الثامن الأساسي في ضوء منظومة القيم الاقتصادية في تنمية الوعي الاستهلاكي لدى الطلاب في الأردن, وأوصت الدراسة باعتماد الوحدة المطورة في كتاب الجغرافيا لتدريس طلبة الصف الثامن الأساسي

    Synthesis and Characterization of Cu(I)-Folic Acid Complex A Theoretical and Experimental Study

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    Copper (I) complex containing folic acid ligand was prepared and characterized on the basis of metal analyses, UV-VIS, FTIR spectroscopies and magnetic susceptibility. The density functional theory (DFT) as molecular modeling calculations was used to determine the donor atoms of folic acid ligand which appear clearly at oxygen atoms binding to hydrogen. Detection of donation sights is supported by theoretical parameters such as geometry, mulliken population, mulliken charge and HOMO-LUMO gap obtained by DFT calculations

    Production of Partially Purified Collagenase from Bacillus licheniformis and It’s Use to Tenderize Aged Buffalo Meat

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    This study aimed to isolate and identify the Bacillus licheniformis bacteria that produces the enzyme collagenase. Due to the selective nature of this enzyme in breaking down and degrading collagen, it was used to tenderize aged buffalo meat. The bacterial isolates were screened using a selective medium and then grown on collagen-agar medium to identify enzyme-producing isolates. Thirteen enzyme-producing isolates were obtained based on the formation of a transparent corona around the colony. Biochemical assessments of the bacterial isolates were carried out using the ABIS online program. The isolates BL1–BL9, BL12 and BL13 were found to be related to B. licheniformis with a percentage match of 98%, while BL10 and BL11 were related to Bacillus pumilus and Bacillus subtilis with a percentage match of 95% and 95.3%, respectively. The enzyme activity of the isolates varied, with the highest activity reaching 200.71 units.ml-1 for isolate BL12. The enzyme of this isolate was chosen to complete the other tests. The optimal time required to obtain the highest enzymatic activity was found to be 20 h, which amounted to 210.25 units.ml-1, with a specific activity of 135.64 units.ml-1. The enzyme was partially purified using ammonium sulphate at a saturation rate of 20–70% as it showed an enzymatic activity and specificity of 355.81 units.ml-1 and a specific activity of 423.58 units.ml-1. Partially purified collagenase was used to tenderize aged buffalo meat. The results showed that treating aged buffalo meat with the enzyme solution for different immersion durations improved the pH, water-holding capacity (WHC) and cooking yield, with an increase in the concentration of hydroxyproline and a significant percentage of soluble collagen; the treated samples showed the best properties with a 60-min immersion duration

    Hiding data in images using steganography techniques with compression algorithms

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    Steganography is the science and art of secret communication between two sides that attempt to hide the content of the message. It is the science of embedding information into the cover image without causing a loss in the cover image after embedding.Steganography is the art and technology of writing hidden messages in such a manner that no person, apart from the sender and supposed recipient, suspects the lifestyles of the message. It is gaining huge attention these days as it does now not attract attention to its information's existence. In this paper, a comparison of two different techniques is given. The first technique used Least Significant Bit (LSB) with no encryption and no compression. In the second technique, the secret message is encrypted first then LSB technique is applied. Moreover, Discrete Cosine Transform (DCT) is used to transform the image into the frequency domain. The LSB algorithm is implemented in spatial domain in which the payload bits are inserted into the least significant bits of cover image to develop the stego-image while DCT algorithm is implemented in frequency domain in which the stego-image is transformed from spatial domain to the frequency domain and the payload bits are inserted into the frequency components of the cover image.The performance of these two techniques is evaluated on the basis of the parameters MSE and PSNR
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