Search for physics beyond the standard model at particle colliders using machine learning techniques

Both ATLAS and CMS collaborations have reported the discovery of a res- onance with a mass around 125 GeV, immediately associated with the long sought after Higgs boson. With this discovery, the standard model (SM) of particle physics is considered to be complete. However, non-vanishing neu- trino masses provide the first confirmed hint towards physics beyond the SM. Extending the SM by sterile neutrinos can naturally explain the smallness of neutrino masses as observed by neutrino oscillation. Moreover, the problem of naturalness and the meta stability of the SM vacuum are hints for extending the SM scalar potential. A well motivated framework to naturally extend the SM scalar sector is to add SU(2)L complex scalar singlet, doublet or triplet to the SM Lagrangian. These hypothetical particles, the additional neutrinos or scalars, can give rise to a testable phenomenology when they have masses around the electroweak scale. They are actively searched for at the current colliders such as the Large Hadron Collider (LHC). The proposed future col- liders, which are currently in the design phase, will be more powerful than the operated colliders to date. In this dissertation, we investigate various aspects of sterile neutrino and heavy scalar phenomenology as well as the prospects of the current and fu- ture colliders searches for them. In particular, we investigate the prospects of searching for sterile neutrinos in low scale seesaw scenarios via the lepton fla- vor violating (but lepton number conserving) dilepton dijet signature at the high luminosity phase of the current LHC and the proposed Large Hadron electron Collider (LHeC). For part of the parameter space where the sterile neutrino is long lived, where the sterile neutrino mass is less than the W bo- son mass, we investigate the LHeC sensitivity to the displaced vertex search. For sterile neutrino mass above O(TeV) we investigate the LHeC sensitivity to the charged lepton flavor violation processes that can be generated at one loop level. We show that for all sterile neutrino mass range, from 5 GeV up to O(105) GeV, the LHeC could already probe the LFV signatures beyond the current experimental bounds. In the second part of this dissertation, various aspects for heavy scalars ex- tending the SM Lagrangian and various searches for heavy scalars at colliders are investigated. We start with studying the prospects of the LHeC search for heavy neutral scalars within the minimal extension of the SM Lagrangian with one additional complex scalar field. The mixing between the singlet and the SM doublet scalar fields gives rise to a SM like Higgs and a heavy scalar. More- over, it induces phenomenological signatures for the heavy Higgs, analogously to the SM Higgs boson, that can be tested at the LHeC. Using multivariate anal- ysis and machine learning techniques we show that the LHeC could probe the heavy signatures for masses between 200 and 800 GeV beyond the current LHC and its future high luminosity phase sensitivity. Also, the prospect signature of the spontaneous CP violation are investigated via the angular distribution of tau lepton pair produced from heavy scalar decays. For this purpose, we focus on the Two Higgs Doublet Model, as an ex- ample model, which can offer a source for CP violation in its scalar potential. Considering a benchmark point that is compatible with the current constraints but within reach of the high luminosity LHC, we study the prospects of de- termining the CP property of a heavy neutral Higgs state. We show that CP conservation in the scalar sector can be excluded at the 90% CL for a bench- mark point with maximal CP violation if the background can be controlled with a relative accuracy of 0.5%, which could be the accuracy target for future LHC measurements. Finally, we study the phenomenology of the minimal extension of the SM La- grangian with a scalar triplet field. The precedence of this scenario over any other consideration that after the symmetry breaking, when the components of the triplet field have masses around the electroweak scale, the model fea- tures a rich phenomenology. We discuss the current allowed parameter space taking into account all relevant constraints, including charged lepton flavour violation as well as collider search. In part of the parameter space the triplet components can be long lived, with displaced distance, in the range of cm, potentially leading to a characteristic displaced vertex signature where the doubly charged component decays into same sign charged leptons. The fact that the LHC is looking for doubly charged scalars via track only analysis or charged stable particles, makes this part of the parameter space still untested by the current LHC measurements. By performing a detailed analysis at the reconstructed level we show that already at the current run of the LHC a dis- covery would be possible for the considered parameter point, via dedicated searches for displaced vertex signatures

Future Anxiety and its Relationship to Students' Attitude toward Academic Specialization

Future anxiety is considered one of the main features as a result of economic and social changes, and increasingly emerges among university students not only because of the fear of failure in the study, but also because of the fear of lack of job opportunities – the thing that affects joining their specializations. Hence this study examines the relationship between future anxiety and specialization in the light of variables of gender and specialization. The sample consists of 380 males and females at Najran University (200 students in Humanities and 180 students in Scientific specializations), and their age ranged between 18 to 22 years. The two scales of future anxiety and specialization have been applied. The results showed a negative correlation between future anxiety and specialization, and there are differences in future anxiety for students of Humanity specializations, and gender differences in favor of males; the study also resulted in differences in the attitude towards specialization in favor of students of scientific specializations that have no differences due to gender. Keywords: future anxiety, attitudes, specialization and university student

Radio Resource Management Optimization For Next Generation Wireless Networks

The prominent versatility of today’s mobile broadband services and the rapid advancements in the cellular phones industry have led to a tremendous expansion in the wireless market volume. Despite the continuous progress in the radio-access technologies to cope with that expansion, many challenges still remain that need to be addressed by both the research and industrial sectors. One of the many remaining challenges is the efficient allocation and management of wireless network resources when using the latest cellular radio technologies (e.g., 4G). The importance of the problem stems from the scarcity of the wireless spectral resources, the large number of users sharing these resources, the dynamic behavior of generated traffic, and the stochastic nature of wireless channels. These limitations are further tightened as the provider’s commitment to high quality-of-service (QoS) levels especially data rate, delay and delay jitter besides the system’s spectral and energy efficiencies. In this dissertation, we strive to solve this problem by presenting novel cross-layer resource allocation schemes to address the efficient utilization of available resources versus QoS challenges using various optimization techniques. The main objective of this dissertation is to propose a new predictive resource allocation methodology using an agile ray tracing (RT) channel prediction approach. It is divided into two parts. The first part deals with the theoretical and implementational aspects of the ray tracing prediction model, and its validation. In the second part, a novel RT-based scheduling system within the evolving cloud radio access network (C-RAN) architecture is proposed. The impact of the proposed model on addressing the long term evolution (LTE) network limitations is then rigorously investigated in the form of optimization problems. The main contributions of this dissertation encompass the design of several heuristic solutions based on our novel RT-based scheduling model, developed to meet the aforementioned objectives while considering the co-existing limitations in the context of LTE networks. Both analytical and numerical methods are used within this thesis framework. Theoretical results are validated with numerical simulations. The obtained results demonstrate the effectiveness of our proposed solutions to meet the objectives subject to limitations and constraints compared to other published works

Mechanisms controlling the cell body response to axon injury in dorsal root ganglion neurons

Successful axon regeneration appears to depend on the development of an injury response. Dorsal root ganglion neurons exemplify the necessity of this injury response in a unique way. Peripheral nerve transection leads to development of an injury response and successful regeneration whereas central root transection does neither. The injury response may involve extracellular and intracellular pathways. To investigate the extraneuronal influences, we performed nerve transection of either the central or peripheral axon branches and studied the expression of GAP-43, a key growth associated protein, and the transcription factors ATF3, c-Jun, and STAT3. Our results show that the responses to peripheral versus central nerve transection are fundamentally different. Peripheral but not central nerve transection increases GAP-43, ATF3, and c-Jun expression. STAT3, however, is upregulated as a result of central but not peripheral nerve transection. To investigate potential intracellular signalling pathways, we applied FGF-2, an extracellular mitogen, or an analog of cAMP, an intracellular second messenger to the cut end of the peripheral axon. Our results indicate that FGF-2 and cAMP act as activators of GAP-43 expression. On the other hand, FGF-2 and cAMP act to downregulate the expression of ATF3. FGF-2 upregulates c-Jun and the activated form of STAT3. Paradoxically, the regulation of GAP-43 expression by cAMP or by FGF-2 in vivo shows opposing results from the previously reported in vitro studies. Our present results suggest that the peripheral nerve injury response may be governed by at least three different signalling pathways

Tall Buildings in Dubai—Converting Architecture into Reality

In just over two decades, Dubai has transformed from a desert served by a single port to a flourishing metropolis. Dubai alone is the home to 20% of the world’s tallest 50 buildings. This transformation brings new challenges to the city during construction and post completion. The surrounding areas will be affected by these skyscrapers from transportation, traffic constraints, parking, power and water consumption and other factors. The cost of building a skyscraper remains the major obstacle with the need to source out new materials other than steel and concrete. Also, moving people around efficiently in super tall buildings is another challenge for engineers keeping in mind the unique designs that architects are looking after. Once all design aspects are concluded and approved by different stakeholders, it will move on to the next phase which is construction, that is called: Reality.Construction realization is the focus of this paper. It will discuss the actual facts and surprises which will be encountered during the transformation of the design into shop drawings and tangible concrete. A physical case study from a busy district in the city of Dubai is the main focus of this study along with the core challenges and obstacles faced the team during the execution phase. Also, this review will debate couple of design elements that were considered as a design feature then developed to be a real construction challenge.Originality/value: the paper will focus on a case study of a high-end skyscrapers designed and built in the city of Dubai in a dense area and the challenges faced by the team during construction. These challenges are beneficial to understand since they will help architects and designers to take into consideration during their studies