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The author focuses on usefulness of antiviral drugs for treatment of Alzheimer's disease and mentions degeneration of neurons involved in the neuron. Topics discussed include case study of postmortem brain tissue from patient Auguste Deter, amyloid beta (Aβ) considered as cause of the diseases which is knowns as amyloid cascade hypothesis and limited therapeutics shown by compounds that deplete Aβ.

In the Initial Orbit Determination (IOD) context, Admissible Regions are subsets of parameter space of orbital elements that are reckoned as functions of the tracking measurement variables. Physically acceptable orbits, e.g., orbits with negative energies, constitute an Admissible Region. This paper defines sets of orbits that satisfy constraints imposed by the measurement variables. Using a probabilistic representation of constraints on some of the orbital parameters the Admissible Region can be further constrained to give a Probabilistic Admissible Region (PAR). PAR gives a particle cloud representation of the initial probability density function (pdf) of the state of a Resident Space Object (RSO). This paper presents a geometric solution to the Probabilistic Admissible Region (G-PAR). G-PAR is a set of algorithms sharing the same underlying template that geometrically maps postulated statistics on some orbital elements and statistics of the measurement process to the uncertainty in the states. The proposed scheme gives a simple closed-form solution for mapping particles to get the PAR pdffor the first time. This speeds up the PAR initial orbit determination with a single partial state measurement. The effectiveness of the proposed G-PAR is shown on diverse combinations of sensors and prior knowledge.

The article discusses science communication and efforts to prevent disinformation in science. It references the author's personal experience from 2011-2015 in contesting the fraudulent information on the supposed cure for HIV and hepatitis C espoused by the Egyptian Major General Ibrahim Abdel-Aty known as "Kofta-Gate," including within the context of Egypt's politics.

To date, most light curve analyses take place using time and frequency domain analyses that generally lack in their ability to quantify the information content of the data. In this paper, we examine the information content of light curves using information theoretic and functional data approaches to characterize physical and dynamic attributes of space objects from non-resolved photometric observations. The information content is examined in a probabilistic context where a set of simulated light curves for a diverse set of object shapes, sizes and dynamics are used to demonstrate the application and value of Functional Data Analysis, data clustering and information theory. The results confirm the value of these approaches by correctly categorizing independent sets of light curve measurements and quantifying the likelihood of a given light curve being associated with a specific object. These analytical tools can also be applied to better understand how well a given set of observations characterize an object and, hence, guide the necessity of future observations. In this paper, we also comment on how the proposed ideas can enable the use of light curves, treated as a functional observation, for joint object tracking and characterization within a multi-hypothesis testing framework such as Finite Set Statistics.

A hybrid control methodology is presented for autonomous rendezvous, proximity operations and docking of a pair of spacecraft. For the theoretical development of the control algorithms, the dynamics of the spacecraft are modeled using the Clohessy-Wiltshire-Hill equations, which result in a linear system of relative motion equations. Only in-plane motion is considered, resulting in a two-dimensional system, and the control input is the acceleration vector of the active spacecraft, constrained by a maximum thrust value. Individual controllers are designed for different phases of the of approach and transitions are governed by a hybrid supervising algorithm. The hybrid control algorithm is implemented both in MATLAB, using a simplified dynamic model, as well as in actual spacecraft flight code and tested in a high-fidelity spacecraft simulation test environment.

Cesarean delivery rates have been steadily rising since the beginning of the 21st century. The growing incidence is even more prominent in developing countries owing to lack of evidence-based guidance and audit, and the expansion of private practice. The uprise in Cesarean delivery rate has been associated with considerable financial burden and has increased the risk otherwise uncommon serious complications such as placenta accreta disorders and uterine rupture. In addition to primary prevention of Cesarean delivery, trial of labor after cesarean section is one of the most successful strategies to reduce Cesarean deliveries and minimize risks associated with higher order Cesarean deliveries. This guideline appraises patient selection strategies and use of prediction model to promote counseling and enhance safety in women considering vaginal birth after Cesarean.

In this paper, a novel dynamic awareness model is proposed and applied to coverage control over large-scale task domains using a decentralized multi-vehicle sensor network with intermittent communications and/or faulty sensors. For each vehicle, an individual state of awareness is defined. The individual vehicle's state of awareness continuously evolves based on the vehicle's motion and is updated at discrete instants whenever the vehicle establishes a communication link with other vehicles. This information sharing update step aids in reducing the amount of redundant coverage. Based on this awareness model, a decentralized control strategy is proposed that guarantees that every point within the task domain will be covered with a satisfactory state of awareness under intermittent communications and/or faulty sensors. We demonstrate the results using numerical simulations. [ABSTRACT FROM AUTHOR]

In this paper, we use an affine connection formulation to study an optimal control problem for a class of nonholonomic, underactuated mechanical systems. In particular, we aim to minimize the norm-squared of the control input to move the system from an initial to a terminal state. We consider systems evolving on general manifolds. The class of nonholonomic systems we study in this paper includes, in particular, wheeled-type vehicles, which are important for many robotic locomotion systems. The two special aspects of this optimal control problem are the nonholonomic constraints and underactuation. Nonholonomic constraints restrict the evolution of the system to a distribution on the manifold. The non-holonomic connection is used to express the constrained equations of motion. Many robotic systems are underactuated since control inputs are usually applied through the robot's internal configuration space only. While we do not consider symmetries with respect to group actions in this paper, the fact that the system is under-actuated is taken into account in our problem formulation. This allows one to compute reaction forces due to any inputs applied in directions orthogonal to the constraint distribution. We illustrate our ideas by considering a simple example on a three-dimensional manifold, including obstacle avoidance using the method of navigation functions. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we study shape-preserving formations of three spacecraft, where the formation keeping forces arise from the electric charges deposed on each craft. Inspired by Lagrange’s 3-body problem, the general conditions that guarantee preservation of the geometric shape of the electrically charged formation are derived. While the classical collinear configuration is a solution to the problem, the equilateral triangle configuration is found to only occur with unbounded relative motion. The three collinear spacecraft problem is analyzed and the possible solutions are categorized based on the spacecraft mass–charge ratio. Precise statements on the number of solutions associated with each category are provided. Finally, a methodology is proposed to study boundedness of the collinear solution that is inspired by past understanding and results for the 3-body problem. Given the initial position and the velocity vectors of each craft along with the charges, analytical solutions are provided describing the resulting relative motion.

This paper revisits a class of Earth-orbiting interferometric observatories introduced previously and reviews the general procedures to achieve wave-number plane coverage. The effect of eccentric spacecraft trajectories and gravity field J2perturbations on wave-number plane coverage are considered. Conditions for complete wave-number plane coverage are found for certain classes of orbit perturbations. This analysis leads to design criteria for interferometric observatories that ensure wave-number plane coverage as a function of perturbation strength.

Human adenovirus (HAdV) infection is common in the general population and can cause a range of clinical manifestations, among which pneumonia and keratoconjunctivitis are the most common. Although HAdV infections are mostly self-limiting, infections in immunocompromised individuals can be severe. No antiviral drug has been approved for treating adenoviruses. Filociclovir (FCV) is a nucleoside analogue which has successfully completed phase I human clinical safety studies and is now being developed for treatment of human cytomegalovirus (HCMV)-related disease in immunocompromised patients.

To determine the mechanism of action of third-generation methylenecyclopropane nucleoside analogs (MCPNAs), DNA sequencing of herpes simplex virus 1 (HSV-1) isolates resistant to third-generation MCPNAs resulted in the discovery of G841S and N815S mutations in HSV-1 UL30.