Characterisation of Rocking Ratchet with Cold 87Rb Atoms

تم دراسة خصائص ظاهرة التيار الذري الهزاز Rocking ratchet)  (باستخدام ذرات الربيديوم المبردة 87Rb داخل الشبيكة البصرية ذات بعد واحد Configuration)   .(تم قياس درجة حرارة الغيمة الذرية الباردة باستخدام تقنية زمن الطيران ) (Time of Flight وهي . تم حساب عدد الذرات المقتنصة في المصيدة البصرية المغناطيسية باستخدام التصوير بالامتصاص وكانت بحدود     ذرة. النتيجة بينت تغير سعة التيار الذري عند تغيير معلمات الشبيكة البصرية. تم تضمين احد اشعة الشبيكة البصرية الليزرية بموجات ذات شدات مختلفة حيث تم ملاحظة أعلى تيار ذري عند اكبر عمق تضمين و ان سعة التيار تعتمد ايضاً على ترددات التضمين وان النتيجة بينت امكانية وجود تردد اهتزازي (Vibrational frequency)    كما تم ملاحظة تغير سعة التيار الذري بتغيير سعة الموجه المضمنه لاحد الاشعة للشبيكة البصرية وبذلك يتم التحكم بالتيار الذري عن طريق تغيير معلمات الشبيكة البصرية.     A rocking ratchet phenomenon of directed transport is demonstrated. This has been realised with cold rubidium atoms in one dimensional dissipative optical lattice with lin lin configuration. The temperature of the cold atomic cloud is measured by time of flight technique with 29 . The atom number trapped in the MOT is determined using absorption imaging to be  atoms. The results show the influence of the atomic current amplitude by varying the lattice beams parameters. One of the lattice beams is modulated with different modulation depths. It shows that highest modulation values have a higher atomic current. The current amplitude is also depending on the modulation frequencies. The results indicate the possibility of existence the vibrational frequency. The harmonic amplitude ratio varied and found the ratchet current is growing with increasing the amplitude of one of the lattice beams and at a certain value goes dow

Exploring the Integration of Memory Management and Trusted Computing

This thesis addresses vulnerabilities in current Trusted Computing architecture by exploring a design for a better Trusted Platform Module (TPM); one that integrates more closely with the CPU\u27s Memory Management Unit (MMU). We establish that software-based attacks on trusted memory can be carried out undetectably by an adversary on current TCG/TPM implementations. We demonstrate that an attacker with sufficient privileges can compromise the integrity of a TPM-protected system by modifying critical loaded code and static data after measurement has taken place. More specifically, these attacks illustrate the Time Of Check vs. Time of Use (TOCTOU) class of attacks. We propose to enhance the MMU, enabling it to detect when memory containing trusted code or data is being maliciously modified at run-time. On detection, it should be able to notify the TPM of these modifications. We seek to use the concepts of selective memory immutability as a security tool to harden the MMU, which will result in a more robust TCG/TPM implementation. To substantiate our ideas for this proposed hardware feature, we designed and implemented a software prototype system, which employs the monitoring capabilities of the Xen virtual machine monitor. We performed a security evaluation of our prototype and validated that it can detect all our software-based TOCTOU attacks. We applied our prototype to verify the integrity of data associated with an application, as well as suggested and implemented ways to prevent unauthorized use of data by associating it with its owner process. Our performance evaluation reveals minimal overhead

Realisation and Characterisation the BEC for 87Rb Atoms

تكاثف بوز- انشتاين هي حالة من حالات المادة يتم خلقها عن طريق تبريد ذرات غاز لدرجة حرارية فائقة الأنخفاض وبكثافة منخفضة جداً. تم توليد تكاثف بوز- انشتاين الى ذرات 87Rb عن طريق المصيدة المغناطيسية بترتيب يطلق عليه Quadrupole –Ioffe Configuration  الذي يتكون من مجال مغناطيسي رباعي يتولد عن رتيب زوج من الملفات بترتيب يسمى Anti-Helmholtz coils  . كما يستخدم سلك منفرد اضافي يولد مجال عمودي على المجال السابق يطلق عليه Offset coil  والغرض منه هو كبح انتقالات ماجورانا Majorana flip-flop  . اول خطوات العمل هو تبريد وقنص الذرات باستخدام الليزر في المصيدة المغناطيسية الضوئية Magneto-Optical Trap  وصولاً الى عدد ذرات بحدود  ذرة بزمن 3 ثواني. بعد ذلك يتم تبريد الذرات في ميكانيكية Optical Molasses  للوصول الى درجة حرارة أقل وتحقيقاً لكثافة ذرية عالية. الخطوة التالية هوتحميل الذرات الى المصيدة المغناطيسية بزمن عمر قدره    وهو كافي لتبريد الذرات لدرجة حرارية اقل لعملية التبخير Evaporative cooling  ومن ثم انتاج ال BEC  . يتم التبريد بالتبخير باستخدام ترددات راديوية للوصول الى انتقال الطور الى BEC  . تم قياس درجة حرارة الذرات باستخدام تقنية زمن الطيران Time Of Flight  وان سرعة تمدد الغيمة الذرية قيست بمقدار     والتي تودي الى قياس درجة الحرارة بمقدار  and   وهي مقاربة الى درجة حرارة الارتداد Recoil temperature للربيديوم.The Bose-Einstein condensate (BEC) is created in a magnetic trap in the Quadrupole-Ioffe configuration (QUIC). This kind of trap combines an anti-Helmholtz quadrupole field with an offset field produced by a single coil perpendicular to the quadrupole field axis to suppress Majorana transitions. In the quadrupole trap evaporative cooling is performed by using radio frequency, reaching the phase transition to a BEC in the QUIC trap. By using Time of Flight (TOF) technique, the expansion velocity is measured with  and  which lead to temperature of  and  It is roughly around the recoil temperature. &nbsp

A Novel Approach for Compressing Surveillance System Videos

The surveillance systems are expected to record the videos in 24/7 and obviously it requires a huge storage space. Even though the hard disks are cheaper today, the number of CCTV cameras is also vertically increasing in order to boost up security. The video compression techniques is the only better option to reduce required the storage space; however, the existing video compression techniques are not adequate at all for the modern digital surveillance system monitoring as they require huge video streams. In this paper, a novel video compression technique is presented with a critical analysis of the experimental results

Supplemental Primary Tooth: A Review & Report Of A Rare Occurrence

Supernumerary teeth, is defined as teeth that exceed the normal dental formula, regardless of their location and morphology and can be found in almost any region of the dental arch both in the primary and permanent dentition. A Supplemental Tooth is a type of supernumerary tooth that is so well formed that it mimics a fully formed tooth. It usually appears distal to a lateral incisor. Its detection requires the careful counting and identification of each tooth in the dental arch. Although many theories have been proposed, the cause is poorly understood. World-wide, few studies have measured the prevalence in the primary dentition, and statistics quoted in the dental literature are inconsistent.  While this discrepancy may be the result of a difference in detection, with primary teeth being more likely to be missing because of exfoliation or early extraction, it has also been postulated that disturbances in interactions between epithelium and mesenchyme, which affect tooth development, are less likely to occur in primary teeth because of the more stable environment prior to birth.This Paper Attempts to review the Occurrence of Supplemental Tooth in the Primary Dentition & report a rare Case of a Supplemental Maxillary Canine

A Role for the SmpB-SsrA System in Yersinia pseudotuberculosis Pathogenesis

Yersinia utilizes a sophisticated type III secretion system to enhance its chances of survival and to overcome the host immune system. SmpB (small protein B) and SsrA (small stable RNA A) are components of a unique bacterial translational control system that help maintain the bacterial translational machinery in a fully operational state. We have found that loss of the SmpB-SsrA function causes acute defects in the ability of Yersinia pseudotuberculosis to survive in hostile environments. Most significantly, we show that mutations in smpB-ssrA genes render the bacterium avirulent and unable to cause mortality in mice. Consistent with these observations, we show that the mutant strain is unable to proliferate in macrophages and exhibits delayed Yop-mediated host cell cytotoxicity. Correspondingly, we demonstrate that the smpB-ssrA mutant suffers severe deficiencies in expression and secretion of Yersinia virulence effector proteins, and that this defect is at the level of transcription. Of further interest is the finding that the SmpB-SsrA system might play a similar role in the related type III secretion system that governs flagella assembly and bacterial motility. These findings highlight the significance of the SmpB-SsrA system in bacterial pathogenesis, survival under adverse environmental conditions, and motility

Optimization of deep learning features for age-invariant face recognition

This paper presents a methodology for Age-Invariant Face Recognition (AIFR), based on the optimization of deep learning features. The proposed method extracts deep learning features using transfer deep learning, extracted from the unprocessed face images. To optimize the extracted features, a Genetic Algorithm (GA) procedure is designed in order to select the most relevant features to the problem of identifying a person based on his/her facial images over different ages. For classification, K-Nearest Neighbor (KNN) classifiers with different distance metrics are investigated, i.e., Correlation, Euclidian, Cosine, and Manhattan distance metrics. Experimental results using a Manhattan distance KNN classifier achieves the best Rank-1 recognition rate of 86.2% and 96% on the standard FGNET and MORPH datasets, respectively. Compared to the state-of-the-art methods, our proposed method needs no preprocessing stages. In addition, the experiments show its privilege over other related methods

Knowledge, attitude and practice of Tanta University medical students towards hepatitis B and C

Background: Egypt lies among the world’s highest prevalence rates of HCV and intermediate levels of HBV infection. The objectives of the study were detection of the knowledge, attitude and practice of Medical Students of Tanta University towards hepatitis B and C.Methods: This was a cross-sectional study, conducted in The Faculty of Medicine, Tanta University, Egypt; from 15th October 2013 to 15th of January 2014.Results: The study included 185 Students; their ages ranged between 17 to 28 years with a mean 20±1.731years. Sixty percent of students were males and 65% were urban residents. 50.8% of the participants were in the basic level of the academic study. More than half (57.85%) of the participants had sufficient knowledge, 77.3% of them had a positive attitude towards hepatitis C and B and more than two-thirds (68.1%) showed good practice. A significant association occurred between a positive attitude and good practice. Sufficient knowledge was significantly recorded among older students, females, urban residents and the clinical stage students. The most frequent sources of student information were family or friends, internet followed by TV or radio, healthcare workers, and newspapers.Conclusions: The students had reasonable knowledge, positive attitude and good practices towards B and C viral hepatitis. Areas of insufficient knowledge needed to be reinforced included some modes of transmission, complications, and treatment for B and C viral hepatitis

Genetic Basis of Attention Deficit Hyperactivity Disorder

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common neuropsychiatric disorders of childhood. Due to studies reporting that the effects of ADHD diagnosis on functioning may last throughout life, this disorder, which has great importance for child and adolescent psychiatry, started to attract greater attention recently in terms of adult psychiatry. A review, evaluating the results of studies conducted on the genetic basis of ADHD, which started to attract increasing attention both in our country and the world, was thought to help clinicians working in this field. PubMed and Turkish Psychiatry Index online search engines were screened using “attention deficit hyperactivity disorder”, “ADHD”, “genetics” as key words. The data obtained were combined with information gleaned from several textbooks. Based on previous studies, it could easily be concluded that ADHD is one of the most common heritable psychiatric disorder with distinguished genetic features. Despite its importance for diagnosis and treatment, the etiology of ADHD is still not clear and the disorder seems to be a complex problem arising from the effects of both genetic and environmental factors. Although previous studies revealed that ADHD displayed familial and hereditary transmission, stable patterns of Mendelian inheritance could not be discriminated by evaluation of pedigrees. Therefore, many studies have been conducted on the molecular genetic basis of ADHD recently. The previous studies did not report consistent results in identification of the genes responsible for ADHD which has been partially linked to heterogeneity of the disorder. Grouping relevant patients according to comorbidities and persistence in adolescence rather than DSM-IV subtypes could be an important alternative method for overcoming this limitation in the research studies