1,573 research outputs found

    Study To Assess Knowledge and Attitude of Hepatitis B Among Medical Students

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    Background: HBV among health care professionalscan be prevented by strategies like vaccination, increasing awareness and following universal precautions. The present study was conducted on medical studentsto evaluate knowledge regarding Hepatitis BVirus and to know their vaccination status. Methodology: Cross sectional study was carried out onIst year MBBS students of BLDEU Shri B.M. Patil medical college Vijaypur.  All the students who were present on the day of data collection were included in the study and interviewed using pretestedquestionnaire. Data was analyzed using percentages. Results-Most of the students had good knowledge about disease, causative agent and modes of transmission & prevention. Astonigshly half of them were unaware of high risk of transmission to health professional. Conclusion –It is recommended for Hepatitis B vaccination for all unimmunized students who enter medical profession. The orientation and sensitization programme should be held to create awareness regarding HBV infection

    Optimizing quantum error correction for superconducting qubit processors

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    The theory of quantum mechanics describes many phenomena that may initially seem to be counter-intuitive and, in some cases, impossible, given the understanding of classical mechanics that most of us are more intimately familiar with. Following its initial introduction, there was a great deal of debate among scientists regarding the predictions made by this theory. The strange nature of quantum mechanics has led to many memorable quotes and the use of “spooky” to describe some of these predictions. Since its initial introduction, quantum mechanics has been rigorously tested and has proven to be quite a successful theory. Quantum mechanics has found many different applications and has led to the existence of devices and technologies we use daily. Another potential application of quantum mechanics is quantum computation, which Richard Feynman first put forward as an idea in 1982. Quantum computers have the potential to solve specific problems that can be infeasible for even the most powerful (classical) supercomputers and have potential applications in many different areas, such as quantum chemistry, cryptography, and optimization. However, performing a quantum computation is challenging and requires overcoming the inherent fragility of quantum systems. Storing information in a quantum system requires it to be well isolated from the environment to avoid any unwanted interactions that can corrupt the stored data. Unfortunately, at the same time, we need the ability to control this system, make it interact with other such systems, and ultimately measure it for us to perform an actual computation. This is a universal issue and all of the systems we have so far developed to be used as quantum bits (qubits) have been plagued by noise. Each operation applied to the qubit or even the act of leaving the qubit idling for some time generally leads to an error with a non-negligible probability. The impact of this noise has so far prevented quantum computers from performing any practical computation. While substantial efforts have been made to reduce these physical error rates over the past several years, we are still far from the universal fault-tolerant quantum computers we ultimately strive for. Fortunately, quantum error correction can help us reach the low error rates necessary for quantum computers to realize their potential applications in the future. This can be achieved by storing the quantum information in a logical qubit instead of a noisy physical one. When using a stabilizer code, which will be the focus of this dissertation, this logical information is distributed over many (noisy) physical qubits, referred to as data qubits. Another set of qubits, the so-called ancilla qubits, is used to perform indirect parity measurements, which do not destroy the stored information but give some information about whether an error has occurred. We then try to interpret this information to identify what errors have happened and correct them, which is done by a classical algorithm referred to as the decoder. Increasing the number of physical qubits used to encode the logical qubits allows more physical errors to be detected and corrected. The number of correctable errors is captured by the distance of the code, defined as the minimum number of physical single-qubit errors that constitute a logical error. One of the critical properties of error correction is the ability to reduce the logical error rate by increasing the code distance, which requires the physical error rates to be below some threshold value. The valiant experimental effort over the years has led to several recent experiments that implement various error-correcting codes and demonstrate the reduction of the error rates promised by error correction. In particular, these experiments (and the experiments leading up to them) identified several noise sources that had not been explored in sufficient detail and could significantly impact the logical performance of the code. In this dissertation, we explore the impact of the noise encountered in transmon-qubit devices on the performance of error-correcting codes, namely the surface code. Transmon qubits are, in practice, multi-level systems, and only the lowest two energy levels are used for computation. Unfortunately, they are also weakly anharmonic, leading to the applied operations having some probability of exciting the qubit outside of this computational subspace, referred to as a leakage error. We explore the impact of leakage in both simulations and experiments and develop schemes to mitigate it. We also consider other approaches to improve the logical performance or to reduce unwanted interactions. In Chapter 2, we develop a realistic model of leakage induced by the two-qubit gates between flux-tunable transmon qubits. We show that leaked qubits effectively spread errors on their neighboring qubits, which are then detected by the parity measurements. We show that a Hidden Markov model can detect the increased error rate due to leakage. This enables us to post-select out runs during which any qubit has leaked to restore the code performance. Unfortunately, post-selection is ultimately not scalable. Instead, it is desirable to have operations that return leaked qubits to the computational subspace. These operations are called leakage-reduction units and convert leakage into a regular error. In Chapter 3, we propose a leakage-reduction scheme, which does not require any overhead in the time needed to perform the parity measurements or an overhead in the quantum hardware. For data qubits, we propose an operation that transfers the leakage to a dedicated readout resonator, where it can quickly decay. This operation is designed to not disturb the computational states, allowing it to be applied unconditionally. For the ancilla qubit, we use the fact that measurements can determine if a qubit is in the leaked state. We then apply a conditional operation to return the qubit to the computational subspace whenever it is measured to be leaked. Using detailed density-matrix simulation, we show that this scheme can be easily implemented to remove qubit leakage from the system, mitigating its impact on the logical performance of the code. In Chapter 4, we realize the data-qubit leakage reduction unit in an experiment and show it can also be used to remove ancilla-qubit leakage, removing the need for fast conditional operations and readout that distinguishes the leaked states. We show that these operations can remove most of the leaked population in about a hundred nanoseconds while having a negligible impact on the computational subspace. We also demonstrate that these operations decrease the number of observed errors by a two-qubit parity check, showing that the effect of leakage can be mitigated. Chapter 5 considers an architecture employing two types of superconducting qubits, the transmon qubit and the fluxonium qubit. These qubits have very different frequencies, making it unclear whether these qubits can even interact with each other in the first place. We show that the interactions with the higher-excited states can be utilized to perform operations between them, and we propose two types of gates. In practice, qubit frequencies are targeted with only a certain precision in fabrication. In certain cases, this can lead to unwanted interaction between qubits that increase the physical error rates, referred to as frequency collisions. We show that the large detuning between these qubits reduces the frequency of frequency collision, thereby increasing the expected fabrication yield. In Chapter 6, we realize a distance-two surface code experiment and perform repeated parity measurements to detect and post-select errors, given that it’s impossible to correct them when using such a small code. We implement a suite of logical operations for this code, including initialization, measurement, and several single-qubit gates. In the context of error detection, a logical operation is said to be fault-tolerant if the errors produced by each operation are detectable. We show that fault-tolerant variants of operations perform better than non-fault-tolerant ones. We also characterize the impact of various noise sources on the code performance. In Chapter 7, we look at another small-distance code, in this case, the distance-seven repetition code. We show that increasing the distance weakly suppresses the logical error rate of the code. We investigate the limiting factors behind the observed logical performance by analyzing the correlation between the observed parity measurements and performing simulations using noise models parameterized by the measured physical error rates. Chapter 8 considers a decoder that can perform the error inference more accurately. In particular, we implement a neural network decoder and investigate how it performs on experimental data from surface code experiments. We show that the accuracy of this decoder approaches what can be achieved by an optimal and computationally inefficient tensor network decoder. Transmon measurement produces analog outcomes. These are then typically converted to binary ones, leading to some information loss. We show how a neural network can also use this analog information to improve the achieved logical performance further. We have investigated the impact of non-conventional errors in simulation and in several experiments, demonstrating the importance of characterizing and mitigating these errors. We expect the methods introduced in this dissertation to lead to lower logical error rates. In the short term, this can aid in demonstrations of the usefulness of error correction. In the long term, addressing such errors is important to ensure the ability to suppress logical error rates to sufficiently low levels. We finish this dissertation with a brief conclusion of each chapter. We also outline several potential challenges that can impact future error-correction experiments, namely how to reduce the larger qubit overhead needed for fault-tolerant computation and several error sources that might become a limiting factor for future error-correction experiments.QCD/Terhal Grou

    Study of maternal and fetal outcome in pregnancy beyond 40 weeks: a prospective observational study at a tertiary institute

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    Background: Prolonged pregnancy is one that exceeds 42 0/7weeks. Management of prolonged pregnancy is very challenging in modern obstetrics.Methods: It is prospective observational study in department of Obstetrics and Gynecology, Shri B.M Patil medical college and Research center, deemed to be University, Vijayapur, North karnataka. Study period was from January 2018 to January 2019.Results: Total of 186 pregnant women were included in the study. Results in terms of age, gravidity, gestational age, time of induction, mode of delivery, neonatal outcome and maternal complications.Conclusion: Pregnancies beyond 40 weeks require early detection, effective fetal monitoring and proper planning of labour. In pregnancies beyond 40 weeks, decision of induction should be taken cautiously as early induction leads to failure of induction and increased rates of lower (uterine) segment Caesarean section (LSCS), while delayed induction leads to increased fetal complications

    Monitoring biodegradation capacity of organic pollutants in the environment

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    Micro-organismen zijn in staat om organische verbindingen om te zetten in minder schadelijke stoffen en spelen daarom een belangrijke rol bij het opruimen van milieuvervuiling. Voor beleidsmakers, landgebruikers en landeigenaren is het belangrijk dat er bij milieuverontreiniging goed toezicht wordt gehouden op de biologische afbraakprocessen en dat deze goed worden beheerst. Aangezien microbiële activiteit in het milieu wordt beïnvloed door diverse fysische, geochemische en biologische factoren, is nauwkeurige kennis van het afbraakproces hierbij noodzakelijk. In dit promotieonderzoek wordt de relatie tussen geochemische condities en de biologische afbraakcapaciteit van micro-organismen in het milieu beschreven, inclusief methoden om de activiteit en metabole functies van deze micro-organismen in het milieu te mete

    Building Simplification using Offset Curves obtained from the Straight Skeleton

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    We propose a conceptual simple algorithm based on offset curves obtained from the straight skeleton to simplify building outlines. We present initial results with some real world data and show that the approach can be used to simplify and amalgamate building outlines. We discuss how this approach can be extended to generate smooth transitions for continuous zoom.Accepted Author ManuscriptOLD Department of GIS Technolog

    Bereiding, konformatie en nitratie van alkylbenzenen

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    Applied Science

    EFFECT OF FLY ASH AND RBI GRADE 81 ON SWELLING CHARACTERISTICS OF CLAYEY SOIL

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    The thickness of road depends on geotechnical properties of subgrade soil and traffic intensity. The clayey soil is not suitable for subgrade due to its swelling characteristics. The soil having more liquid limit (LL), lower Maximum dry density (MDD) and higher Optimum moisture content (OMC) is suitable for subgrade of road. The clayey soil having more LL, lower MDD and higher OMC. Therefore clayey soil is not suitable as subgrade soil of roads. This paper deals with stabilization of clayey soil by using fly ash and RBI Grade 81 to improve the geotechnical properties of soil. The fly ash is a thermal waste and RBI Grade 81 is a chemical soil stabilizer. In the laboratory standard Proctor test (SPT), Atterbergs limits and differential free swelling index (DFS) test for different proportions of soil, fly ash and RBI Grade 81conducted. The results show that, the LL, MDD, OMC and DFS index of clayey soil improved considerably. The LL of untreated soil is 67% and it reduces to 46% for mix of soil: fly ash: RBI Grade 81 for 76:20:04 proportion. The DFS of untreated soil is 65% and it reduces to 40% for addition of fly ash and RBI Grade 81

    Effect of industrial waste and RBI Grade 81 on swelling characteristics of clayey soil

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    This paper deals with improvement of swelling characteristics of clayey soil by adding industrial waste and RBI Grade 81. The construction of road in clayey soil is challenging due to its more swelling and more shrinkage characteristics. To overcome this problem there are two solutions one is replace the clayey soil by good quality granular material. The second is stabilizing the subgrade clayey soil by using various industrial wastes. Generally pond ash, fly ash and stone dust are use for soil stabilization. The swelling and shrinkage characteristics of clayey soil are considerably improved if it treated with industrial wastes and RBI Grade 81. The RBI Grade 81 is chemical soil stabilizer. The differential free swell index (DFS) test was carried out on different mix of soil, industrial waste and RBI Grade 81. The result shows that the DFS index of untreated soil obtained is 65% reduces to 35% by addition of 20% fly ash and 4% RBI Grade 81. This reduction in DFS index helps to reduce the effect of moisture variation in clayey soil
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