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This paper presents a new, simple, and exact solution to the formation keeping of satellites when the relative distance between the satellites is so large that the linearized relative equations of motion no longer hold. We employ a recently proposed approach, the Udwadia-Kalaba approach, which makes it possible to explicitly obtain the desired control function without making any approximations related to the nonlinearities in the underlying dynamics. We use an inertial frame of reference to describe the motion of a satellite and since no approximations are made, the results obtained apply to situations even when the distance between the satellites is arbitrarily large. The paper deals with a projected circular formation, but the methodology in this paper can be applied to any desired configuration or orbital requirements. Numerical simulations confirm the brevity and the accuracy of the analytical solution to the dynamical control problem developed herein. DOI: 10.1061/(ASCE)AS.1943-5525.0000013 CE Database subject headings: Satellites; Orbits; Simulation.

Background Objective Methods Results Conclusion Parkinson's disease (PD) has been consistently linked to alterations within the gut microbiome.Our goal was to identify microbial features associated with PD incidence and progression.Metagenomic sequencing was used to characterize taxonomic and functional changes to the PD microbiome and to explore their relation to bacterial metabolites and disease progression. Motor and non‐motor symptoms were tracked using Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS‐UPDRS) and levodopa equivalent dose across ≤5 yearly study visits. Stool samples were collected at baseline for metagenomic sequencing (176 PD, 100 controls).PD‐derived stool samples had reduced intermicrobial connectivity and seven differentially abundant species compared to controls. A suite of bacterial functions differed between PD and controls, including depletion of carbohydrate degradation pathways and enrichment of ribosomal genes. Faecalibacterium prausnitzii‐specific reads contributed significantly to more than half of all differentially abundant functional terms. A subset of disease‐associated functional terms correlated with faster progression of MDS‐UPDRS part IV and separated those with slow and fast progression with moderate accuracy within a random forest model (area under curve = 0.70). Most PD‐associated microbial trends were stronger in those with symmetric motor symptoms.We provide further evidence that the PD microbiome is characterized by reduced intermicrobial communication and a shift to proteolytic metabolism in lieu of short‐chain fatty acid production, and suggest that these microbial alterations may be relevant to disease progression. We also describe how our results support the existence of gut‐first versus brain‐first PD subtypes. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

The corrected Hohenberg–Kohn–Sham and corrected Harris total energy functionals recently proposed [B. Zhou and Y. A. Wang, J. Chem. Phys. 128, 084101 (2008)] have been generalized to the Hartree–Fock method. We have tested the functionals on a few molecular systems and found them to be very useful in accelerating the convergence of the total energy during a self-consistent field process. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the geometries, energies, dipole moments and other properties of all tautomers of pyridinethiones. The thione form of the tautomer is dominant for monomers of pyridinethiones.

Introduction: Hearing impairments in Parkinson's Disease (PD) have received limited attention in the past, possibly because PD patients often report no perceived hearing disability, yet negative consequences of hearing impairment might aggravate communication difficulties and social withdrawal., Objective: Our aim was to investigate functional hearing (speech in noise recognition) in PD and evaluate its relationship to neuropsychiatric symptoms, cognition and quality of life., Methods: Participants with PD were recruited in a tertiary movement disorder clinic. Demographic, audiological, neuropsychiatric and quality of life data were collected. Participants underwent pure tone audiometry (PTA) and Hearing in Noise test (HINT) as a part of their audiological evaluation., Results: A total of 29 participants (mean age: 65.8±8.3 years, M:F= 1.6:1, mean disease duration 5.2 ± 4.0 years) completed the study. All assessments were done in the ON state. 19/29 (65.5 %) participants had normal tone audiometry for age; functional hearing loss, however, was present in 17/29 (58.6 %) according to the HINT. 65 % (11/17) of the affected participants had a disease duration of <4 years. The majority (72.4 %) with poor functional hearing did not perceive any hearing impairment. Hearing deficits did not correlate with non-motor symptoms (NMS), including cognition or other quality of life measures., Conclusions: Functional hearing loss is common in PD, often presents early in the disease and the majority of PD patients are unaware of their functional hearing loss. Its potential impact on cognition, communication and quality of life requires further investigation and tailored treatment., Competing Interests: Declaration of Competing Interest None, (Copyright © 2024. Published by Elsevier B.V.)