52 research outputs found

    State estimation technique for a planetary robotic rover

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    Given the long traverse times and severe environmental constraints on a planet like Mars, the only option feasible now is to observe and explore the planet through more sophisticated planetary rovers. To achieve increasingly ambitious mission objectives under such extreme conditions, the rovers must have autonomy. Increased autonomy, obviously, relies on the quality of estimates of rover's state i.e. its position and orientation relative to some starting frame of reference. This research presents a state estimation approach based on Extended Kalman Filter (EKF) to fuse distance from odometry and attitude from an Inertial Measurement Unit (IMU), thus mitigating the errors generated by the use of either system alone. To simulate a Sun-sensor based approach for absolute corrections, a magnetic compass was used to give absolute heading updates. The technique was implemented on MotherBot, a custom-designed skid steered rover. Experimental results validate the application of the presented estimation strategy. It showed an error range within 3% of the distance travelled as compared to about 8% error obtained from direct fusion

    Spatial variations in COVID-19 risk perception and coping mechanism in Pakistan

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    The outbreak of novel coronavirus disease (COVID-19) was declared a pandemic by the World Health Organization, which instigated governments to impose lockdowns across their countries. Amidst the lockdown in Pakistan, this study comprised measures of the COVID-19 risk perception, coping mechanism, and spatial variations. The data from 40 selected indicators was collected using an online questionnaire and grouped into domains (4 risk perception and 3 coping mechanisms domains). The results revealed the spatial variations and the levels of risk perception and coping mechanisms within the study area. Relative to each other, overall risk perception was highest in Northern Areas (Gilgit-Baltistan and Azad Jammu and Kashmir) and Islamabad, and lowest in Balochistan province. Very little spatial variation was observed in terms of coping mechanisms. Age, gender, and marital status influenced the risk perception associated with COVID-19. The findings suggest spatial variation in risk perception, implying the need for localized and modified COVID-19 risk communication and risk reduction strategies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s41324-022-00498-7

    Evaluation Of Antibody Response To Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccination In Patients With Lymphoid And Solid Organ Malignancies

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current COVID-19 pandemic. There is emerging evidence regarding suboptimal response to vaccination against COVID-19 in patients with hematologic and solid organ malignancies. We conducted a single-center prospective study assessing seroconversion in response to vaccination against COVID-19 in 53 patients with chronic lymphocytic leukemia (CLL), non-Hodgkin’s lymphoma (NHL), multiple myeloma (MM), and solid organ malignancies. A quantitative immunoassay of IgG antibodies to SARS-CoV-2 Spike (S) protein was measured prior to vaccination and at 2 weeks after completion of two-dose vaccination series. A fourfold increase in antibody titers was considered positive seroconversion. Through a predesigned survey, patients also self-reported side effects from each dose of vaccination. Seroconversion on vaccination was seen in 6/12 (50%) patients with CLL, 7/11 (63.6%) patients with NHL, 9/10 (90%) patients with MM, and 17/20 (85%) patients with solid organ malignancy. Only 6 of the 14 (42.8%) patients currently on or with previous history of rituximab use seroconverted. Injection site soreness was the most reported side effect. The only severe side effect occurred in a patient with solid organ malignancy who developed Parsonage-Turner syndrome. Patients with CLL and NHL appear less likely to respond to vaccination against COVID-19 in contrast to patients with MM or solid organ malignancies. Previous treatment with rituximab is a possible risk factor for suboptimal response to vaccination. These data highlight the importance of continuing risk mitigation strategies against COVID-19 in individuals with hematologic malignancy, particularly those with CLL or on treatment with rituximab

    The impact of psychological distance to climate change and urban informality on adaptation planning

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    Climate change adaptation planning involves adjusting to the impacts of climate change and taking action to mitigate its adverse effects. Psychological distance, the separation between one's self-perception and actual events, can play a significant role in an individual's readiness to adapt to climate change impacts. This study aims to investigate the socioeconomic factors associated with psychological distance to climate change in formal and informal settlements of Lahore, Pakistan. Using a literature review, data indicators were selected and grouped into the psychological distance dimensions of spatial, temporal, social, and hypothetical. A questionnaire survey was conducted in the study area, resulting in a total of 400 responses. Descriptive statistics and sampled paired t-tests were used to measure differences between responses from formal and informal communities, and multivariate regression models were developed to identify socioeconomic factors associated with psychological distance to climate change. The results of the study indicate a significant difference between formal and informal settlements in spatial distance and hypothetical dimensions. Additionally, household size, average household income, number of children, and past experiences with extreme weather conditions were found to be significant factors. The study recommends that these factors be taken into account when engaging with the public, communicating risks, and devising relevant policies for effective adaptation planning

    Differentiation Syndrome

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    Overview of AML Differentiation Syndrome Conclusio
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