4,366 research outputs found

    Search for Dark Matter with LHC proton Beam Dump

    Full text link
    Dark Matter (DM) comprising particles in the mass range of a few MeV to GeV is waiting to be explored, given the many theoretical models accommodating cosmological abundance. We hereby propose an experiment with the LHC proton beam of 7 TeV striking onto the beam dump target, emitting neutrinos and possibly, Dark Matter candidates. This experiment would also permit to observe signatures involving elastic and inelastic processes involving DM candidates, electrons and strongly interacting particles present in nuclei of the dump target. There will be residual neutrino background present in each of these signatures, hence the proposed experimental detector sub-systems would be such that they would involve as final states, elastically or inelasticity scattered, standard model particles. The bump or the excess in the tail of the kinematic distributions will eventually give us glimpse of presence of new particles which could possibly be Dark Matter candidates. Given the parameters of the LHC machine, the sensitivity of such an experiment is unique in the energy region it is supposed to exploit

    An Interesting Case Of Acute Disseminated Encephalomyelitis

    Get PDF
    Acute disseminated encephalomyelitis (ADEM) is an uncommon inflammatory demyelinating disease of the central nervous system. The disease typically occurs after infections or vaccinations. However, in many patients with ADEM, no evidence of prior infection or vaccination can be found. We are reporting a patient who developed clinical and radiological features of acute disseminated encephalomyelitis after trauma of repeated attempts at lumber puncture for spinal anesthesi

    Design and Implementation of a Re-Configurable Arbitrary Signal Generator and Radio Frequency Spectrum Analyser

    Get PDF
    This research is focused on the design, simulation and implementation of a reconfigurable arbitrary signal generator and the design, simulation and implementation of a radio frequency spectrum analyser based on digital signal processing. Until recently, Application Specific Integrated Circuits (ASICs) were used to produce high performance re-configurable function and arbitrary waveform generators with comprehensive modulation capabilities. However, that situation is now changing with the availability of advanced but low cost Field Programmable Gate Arrays (FPGAs), which could be used as an alternative to ASICs in these applications. The availability of high performance FPGA families opens up the opportunity to compete with ASIC solutions at a fraction of the development cost of an ASIC solution. A fast digital signal processing algorithm for digital waveform generation, using primarily but not limited to Direct Digital Synthesis (DDS) technologies, developed and implemented in a field-configurable logic, with control provided by an embedded microprocessor replacing a high cost ASIC design appeared to be a very attractive concept. This research demonstrates that such a concept is feasible in its entirety. A fully functional, low-complexity, low cost, pulse, Gaussian white noise and DDS based function and arbitrary waveform generator, capable of being amplitude, frequency and phase modulated by an internally generated or external modulating signal was implemented in a low-cost FPGA. The FPGA also included the capabilities to perform pulse width modulation and pulse delay modulation on pulse waveforms. Algorithms to up-convert the sampling rate of the external modulating signal using Cascaded Integrator Comb (CIC) filters and using interpolation method were analysed. Both solutions were implemented to compare their hardware complexities. Analysis of generating noise with user-defined distribution is presented. The ability of triggering the generator by an internally generated or an external event to generate a burst of waveforms where the time between the trigger signal and waveform output is fixed was also implemented in the FPGA. Finally, design of interface to a microprocessor to provide control of the versatile waveform generator was also included in the FPGA. This thesis summarises the literature, design considerations, simulation and implementation of the generator design. The second part of the research is focused on radio frequency spectrum analysis based on digital signal processing. Most existing spectrum analysers are analogue in nature and their complexity increases with frequency. Therefore, the possibility of using digital techniques for spectrum analysis was considered. The aim was to come up with digital system architecture for spectrum analysis and to develop and implement the new approach on a suitable digital platform. This thesis analyses the current literature on shifting algorithms to remove spurious responses and highlights its drawbacks. This thesis also analyses existing literature on quadrature receivers and presents novel adaptation of the existing architectures for application in spectrum analysis. A wide band spectrum analyser receiver with compensation for gain and phase imbalances in the Radio Frequency (RF) input range, as well as compensation for gain and phase imbalances within the Intermediate Frequency (IF) pass band complete with Resolution Band Width (RBW) filtering, Video Band Width (VBW) filtering and amplitude detection was implemented in a low cost FPGA. The ability to extract the modulating signal from a frequency or amplitude modulated RF signal was also implemented. The same family of FPGA used in the generator design was chosen to be the digital platform for this design. This research makes arguments for the new architecture and then summarises the literature, design considerations, simulation and implementation of the new digital algorithm for the radio frequency spectrum analyser

    EQUAL: Energy and QoS Aware Resource Allocation Approach for Clouds

    Get PDF
    The popularity of cloud computing is increasing by leaps and bounds. To cope with resource demands of increasing number of cloud users, the cloud market players establish large sized data centers. The huge energy consumption by the data centers and liability of fulfilling Quality of Service (QoS) requirements of the end users have made resource allocation a challenging task. In this paper, energy and QoS aware resource allocation approach which employs Antlion optimization for allocation of resources to virtual machines (VMs) is proposed. It can operate in three modes, namely power aware, performance aware, and balanced mode. The proposed approach enhances energy efficiency of the cloud infrastructure by improving the utilization of resources while fulfilling QoS requirements of the end users. The proposed approach is implemented in CloudSim. The simulation results have shown improvement in QoS and energy efficiency of the cloud

    Energy Aware Resource Allocation for Clouds Using Two Level Ant Colony Optimization

    Get PDF
    In cloud environment resources are dynamically allocated, adjusted, and deallocated. When to allocate and how many resources to allocate is a challenging task. Resources allocated optimally and at the right time not only improve the utilization of resources but also increase energy efficiency, provider's profit and customers' satisfaction. This paper presents ant colony optimization (ACO) based energy aware solution for resource allocation problem. The proposed energy aware resource allocation (EARA) methodology strives to optimize allocation of resources in order to improve energy efficiency of the cloud infrastructure while satisfying quality of service (QoS) requirements of the end users. Resources are allocated to jobs according to their QoS requirements. For energy efficient and QoS aware allocation of resources, EARA uses ACO at two levels. First level ACO allocates Virtual Machines (VMs) resources to jobs whereas second level ACO allocates Physical Machines (PMs) resources to VMs. Server consolidation and dynamic performance scaling of PMs are employed to conserve energy. The proposed methodology is implemented in CloudSim and the results are compared with existing popular resource allocation methods. Simulation results demonstrate that EARA achieves desired QoS and superior energy gains through better utilization of resources. EARA outperforms major existing resource allocation methods and achieves up to 10.56 % saving in energy consumption

    Successful Surgical Treatment of a Septuagenarian with Anomalous Right Coronary Artery from the Pulmonary Artery with an Eleven Year Follow-Up : Case report and review of literature

    Get PDF
    An anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is a very rare coronary artery anomaly with only 98 cases reported in literature till date. We report the oldest surgically treated patient and the fourth ever septuagenarian with this anomaly diagnosed ante-mortem with an eleven year followup. The literature on this anomaly was reviewed and discussed to highlight the clinical implications

    STUDY OF PANEL OF DIAGNOSTIC CARDIAC MARKERS FOR ACUTE MYOCARDIAL INFARCTION

    Get PDF
    Objectives: The aim of this study is to estimate the level of creatine kinase-myocardial band (CK-MB), C-reactive protein (CRP), and lactate dehydrogenase (LDH) biomarker in myocardial infarction (MI) (troponin T-positive) and compare with normal healthy individuals (Troponin-T [TnT] negative). Methods: A cross-sectional study on 172 patients involving 100 patients with nondiabetic MI and 72 apparently healthy controls with no history of diabetes and/or MI was done from December 2017 to May 2018. The diagnosis of MI was established with electrocardiogram findings and TnT estimation. Blood samples were gathered and processed for the estimation of CK-MB, LDH, and CRP. Results: The mean age of the cases was 62.15±7.75 years and in the controls was 61.49±8.35 years (p=0.592). The mean value of CK-MB, LDH, and CRP in the TnT positive group was 111.94±29.59 IU/L, 564.43±110.99 IU/L, and 15.69±4.04 mg/L, whereas in the TnT negative group was 16.36±3.77 IU/L, 223.68±36.23 IU/L, and 6.08±2.02 mg/L, respectively (p<0.0001). CK-MB was deranged in 100% of TnT positive group, and in only 2.78% in TnT negative group (p<0.0001). LDH was deranged in 100% TnT positive group, and in 16.67% in TnT negative group (p<0.0001). CRP was deranged in 4% TnT positive group, and in 0% in TnT negative group (p=0.141). Conclusion: This study indicated that CK-MB and LDH are sensitive cardiac markers for the diagnosis of MI

    Traits for Screening and Selection of Cowpea Genotypes for Drought Tolerance at Early Stages of Breeding

    Get PDF
    The association of leaf water content with yield-attributes such as pod setting and number of pods/plant and seed yield in cowpea was examined using midday drop of leaf relative water content (RWC) determined from morning (800 h) and midday (1330 h) measurements of RWC. Midday drop of RWC was significantly correlated to pod setting ratio (R2 = 0.80, P 0.01), number of pods/plant (R2 = 0.87, P 0.01) and seed yield (R2 = 0.37, P 0.05). There was a significant genotypic variation for leaf water potential (LWP) at 800 and 1330 h and for RWC at 1330 h. Significant genotypic differences were also observed in pod setting ratio, number of pods/plant, number of seeds/pod, 1000-seed weight, biomass and seed yield. Pod setting ratio was significantly and positively correlated with number of pods/plant (R2 = 0.80, P 0.01) and seed yield (R2 = 0.38, P 0.05). These results showed that the genotypes with a smaller reduction in midday drop of RWC produced a larger number of pods/plant and consequently had higher seed yield as compared with a larger midday drop of RWC. The results also showed that there was a large genotypic variation in the midday drop of RWC, which was correlated with yield-attributes and seed yield. It may therefore be possible to use midday drop of RWC as a screening and selection trait for drought tolerance of cowpea genotypes
    corecore