Theoretical Design and Overview of Steam Propelled and Nuclear Powered Interplanetary Transit Vehicle for Human Crewed Extraterrestrial Exploration

This article provides a theoretical overview of a spacecraft that utilizes extraterrestrial water resources and controlled nuclear fission to propel itself during interplanetary travel. The spacecraft is equipped with a water extraction module to supply water to a large water-boiler container, a small nuclear reactor, a nuclear heat coupler, and an exhaust nozzle for steam propulsion. When the reactor is activated, the water is transformed into steam through nuclear heat and is stored in a pressurized steam chamber. Once the steam reaches a specific pressure limit, it is released through the nozzle, resulting in steam propulsion and the movement of the spacecraft. The velocity of the spacecraft can be adjusted by controlling the injection of steam into the propulsion chamber. In this study, we have examined the feasibility, design overview, and constraints associated with constructing this type of spacecraft in Low Earth Orbit (LEO). The proposed spacecraft aims to provide faster and more reliable interplanetary transit beyond Mars, utilizing renewable energy resources. Since water resources can be found beyond Mars through asteroids, comets, and moons, the challenge lies not in finding water but in the extraction process. Furthermore, the scientific community requires faster transit vehicles for human exploration of Mars and Ceres. However, no architecture has been proposed for crewed exploration beyond this point. Ultimately, it is hoped that this type of spacecraft will enable future astronauts to undertake deep space exploration missions in the coming decades. The manuscript will delve into the design strategy, challenges, launch vehicles needed for deploying assembling instruments, and the assessment of dimensions and crew capability

Development Trends in Wind Energy Conversion System: A Review

Wind energy for electricity production today is a mature, competitive and virtually pollution-free technology widely used in many areas of the world. Wind energy conversion systems have become a focal point in the research of renewable energy sources. This is not only due to the rapid advances in the size of wind generators but also for the improvement of energy electronics and their applicability in wind energy extraction. This paper deals with the recent developments in wind energy conversion systems, their classifications, choice of generators and their social, economic and environmental advantages and disadvantages, a review of the interconnection issues of distributed resources including wind power with electric power systems. DOI: 10.17762/ijritcc2321-8169.150710

Statistical Learning for Resting-State fMRI: Successes and Challenges

International audienceIn the absence of external stimuli, fluctuations in cerebral activity can be used to reveal intrinsic structures. Well-conditioned probabilistic models of this so-called resting-state activity are needed to support neuroscientific hypotheses. Exploring two specific descriptions of resting-state fMRI, namely spatial analysis and connectivity graphs, we discuss the progress brought by statistical learning techniques, but also the neuroscientific picture that they paint, and possible modeling pitfalls

McKay matrices for finite-dimensional Hopf algebras

For a finite-dimensional Hopf algebra $A$, the McKay matrix $M_V$ of an $A$-module $V$ encodes the relations for tensoring the simple $A$-modules with $V$. We prove results about the eigenvalues and the right and left (generalized) eigenvectors of $M_V$ by relating them to characters. We show how the projective McKay matrix $Q_V$ obtained by tensoring the projective indecomposable modules of $A$ with $V$ is related to the McKay matrix of the dual module of $V$. We illustrate these results for the Drinfeld double $D_n$ of the Taft algebra by deriving expressions for the eigenvalues and eigenvectors of $M_V$ and $Q_V$ in terms of several kinds of Chebyshev polynomials. For the matrix $N_V$ that encodes the fusion rules for tensoring $V$ with a basis of projective indecomposable $D_n$-modules for the image of the Cartan map, we show that the eigenvalues and eigenvectors also have such Chebyshev expressions

Resting Network Plasticity Following Brain Injury

The purpose of this study was to examine neural network properties at separate time-points during recovery from traumatic brain injury (TBI) using graph theory. Whole-brain analyses of the topological properties of the fMRI signal were conducted in 6 participants at 3 months and 6 months following severe TBI. Results revealed alterations of network properties including a change in the degree distribution, reduced overall strength in connectivity, and increased “small-worldness” from 3 months to 6 months post injury. The findings here indicate that, during recovery from injury, the strength but not the number of network connections diminishes, so that over the course of recovery, the network begins to approximate what is observed in healthy adults. These are the first data examining functional connectivity in a disrupted neural system during recovery

Predicting streamflow distributions and flow duration curves from landscape and climate

Characterizing the probability distribution of streamflows in catchments lacking in discharge measurements represents an attractive prospect with consequences for practical and scientific applications, in particular water resources management. In this paper, a physically-based analytic model of streamflow dynamics is combined with a set of water balance models and a geomorphological recession flow model in order to estimate streamflow probability distributions based on catchment-scale climatic and morphologic features. The models used are described and the novel parameterization approach is elaborated on. Starting from rainfall data, potential evapotranspiration and digital terrain maps, the method proved capable of capturing the statistics of observed streamflows reasonably well in 11 test catchments distributed throughout the United States, east of the rocky mountains. The method developed offers a unique approach for estimating probability distribution of streamflows where only climatic and geomorphologic features are known

FMRI resting slow fluctuations correlate with the activity of fast cortico-cortical physiological connections

Recording of slow spontaneous fluctuations at rest using functional magnetic resonance imaging (fMRI) allows distinct long-range cortical networks to be identified. The neuronal basis of connectivity as assessed by resting-state fMRI still needs to be fully clarified, considering that these signals are an indirect measure of neuronal activity, reflecting slow local variations in de-oxyhaemoglobin concentration. Here, we combined fMRI with multifocal transcranial magnetic stimulation (TMS), a technique that allows the investigation of the causal neurophysiological interactions occurring in specific cortico-cortical connections. We investigated whether the physiological properties of parieto-frontal circuits mapped with short-latency multifocal TMS at rest may have some relationship with the resting-state fMRI measures of specific resting-state functional networks (RSNs). Results showed that the activity of fast cortico-cortical physiological interactions occurring in the millisecond range correlated selectively with the coupling of fMRI slow oscillations within the same cortical areas that form part of the dorsal attention network, i.e., the attention system believed to be involved in reorientation of attention. We conclude that resting-state fMRI ongoing slow fluctuations likely reflect the interaction of underlying physiological cortico-cortical connections

Diagnosis delay of breast cancer and its associated factors in Malaysian women

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the leading cause of cancer mortality among women in Malaysia. Delayed diagnosis is preventable and has major effects on patients' prognosis and survival. The objectives of our study were to identify the magnitude of delayed diagnosis and its associated factors in women with breast cancer in Malaysia.</p> <p>Methods</p> <p>This study had a cross-sectional design. Respondents had histologically confirmed breast cancer and were registered at five medical centres between 2005 and 2007. All breast cancer patients who attended hospital clinics at the East Coast were included. Patients at Kuala Lumpur hospitals were selected by systematic sampling. A standardised questionnaire was developed to interview respondents. We measured the time from the first recognition of symptoms to the first general practitioners' consultation and to the histological diagnosis of breast cancer. Diagnosis delay was defined when there was more than 6 months from the recognition of symptoms to the histological diagnosis. Multiple logistic regression was used for analysis.</p> <p>Results</p> <p>In total, 328 respondents were included. The mean (standard deviation) age was 47.9 (9.4) years. Most respondents were of Malay ethnicity, were married housewives with a median family income of RM1500 a month. Most respondents had ductal carcinoma (89.3%) and the stage distribution was as follows: 5.2% stage I, 38.7% stage II, 44.8% stage III and 11.3% stage IV. The median time to consultation was 2 months and the median time to diagnosis was 5.5 months. The frequency of diagnosis delay of more than 3 months was 72.6% and delay of more than 6 months occurred in 45.5% of the cases. The factors associated with diagnosis delay included the use of alternative therapy (odds ratio (OR) 1.77; 95% confidence interval (CI): 1.06, 2.94), breast ulcer (OR 5.71; 95% CI: 1.59, 20.47), palpable axillary lymph nodes (OR 2.19; 95% CI: 1.23, 3.90), false-negative diagnostic test (OR 5.32; 95% CI: 2.32, 12.21), non-cancer interpretation (OR 1.68; 95% CI: 1.01, 2.78) and negative attitude toward treatment (OR 2.09; 95% CI: 1.15, 3.82).</p> <p>Conclusions</p> <p>Delays in consultation and diagnosis are serious problems in Malaysia. Diagnosis delay was influenced by complex interactions between many factors. Breast awareness and education are required to promote early detection, diagnosis and treatment before the tumours enlarge and metastasis.</p

COVID-19: Policy Interventions and Socio-economic Impact in Andhra Pradesh, India

The COVID-19 pandemic has claimed several lives and has already adversely affected the livelihoods of millions of vulnerable households. This policy brief surveys the current status of the disease, its spread and its likely socio-economic effects in the context of Andhra Pradesh, India. Given the global scope of the shock, the policy brief emphasizes the need for innovative and bold policy measures, particularly from the states’ perspective

Some Five-Dimensional Bianchi Type-III String Cosmological Models in General Relativity

Abstract. In this paper we have constructed some five-dimensional Bianchi type-III cosmological models in general relativity when source of gravitational field is a massive string. We obtained different classes of solutions by considering different functional forms of metric potentials. It is also observed that one of the models is not physically acceptable and the other models possess big-bang singularity. The physical and kinematical behaviors of the models are discussed