Effects of exoplanetary gravity on human locomotor ability

At some point in the future, if mankind hopes to settle planets outside the Solar System, it will be crucial to determine the range of planetary conditions under which human beings could survive and function. In this article, we apply physical considerations to future exoplanetary biology to determine the limitations which gravity imposes on several systems governing the human body. Initially, we examine the ultimate limits at which the human skeleton breaks and muscles become unable to lift the body from the ground. We also produce a new model for the energetic expenditure of walking, by modelling the leg as an inverted pendulum. Both approaches conclude that, with rigorous training, humans could perform normal locomotion at gravity no higher than 4 $g_{\textrm{Earth}}$.Comment: 12 pages, 4 figures, to be published in The Physics Teache

C9orf72 hexanucleotide repeat allele tagging SNPs : Associations with ALS risk and longevity

Peer reviewe

Associations of subjective and objective cognitive functioning after COVID-19 : A six-month follow-up of ICU, ward, and home-isolated patients

Publisher Copyright: © 2023 The AuthorsBackground: Subjective and objective cognitive dysfunction are reported after COVID-19 but with limited data on their congruence and associations with the severity of the acute disease. The aim of this cohort study is to describe the prevalence of subjective and objective cognitive dysfunction at three and six months after COVID-19 and the associations of subjective cognitive symptoms and psychological and disease-related factors. Methods: We assessed a cohort of 184 patients at three and six months after COVID-19: 82 patients admitted to the Intensive Care Unit (ICU), 53 admitted to regular hospital wards, and 49 isolated at home. A non-COVID control group of 53 individuals was included. Demographic and clinical data were collected. Subjective cognitive symptoms, objective cognitive impairment, and depressive and post-traumatic stress disorder (PTSD) symptoms were assessed. Results: At six months, subjective cognitive impairment was reported by 32.3% of ICU-treated, 37.3% of ward-treated, and 33.3% of home-isolated patients and objective cognitive impairment was observed in 36.1% of ICU-treated, 34.7% of ward-treated, and 8.9% of home-isolated patients. Subjective cognitive symptoms were associated with depressive and PTSD symptoms and female sex, but not with objective cognitive assessment or hospital metrics. Conclusions: One-third of COVID-19 patients, regardless of the acute disease severity, reported high levels of subjective cognitive dysfunction which was not associated with results from objective cognitive screening but with psychological and demographic factors. Our study stresses the importance of thorough assessment of patients reporting long-term subjective symptoms, screening for underlying mental health related factors such as PTSD or depression.Peer reviewe

Efficient isogeometric shell element with through-thickness stretch: application to incremental sheet forming

An isogeometric shell element with through-thickness stretch is applied to a two-point incremental forming problem. The shell element supports full three-dimensional constitutive laws and therefore does not make the plane stress assumption. An anisotropic material model is implemented to account for the sheet rolling direction. Automatically adjusting penalty stiffness is proposed for modeling the contact between the stylus tool and the sheet, whereas the die contact algorithm uses traditional constant penalty stiffness. A comparison is made between experimental results as well as results from a conventional shell formulation

From Extractivism to Global Extractivism : The Evolution of an Organizing Concept

All the named authors were members of the Helsinki Research Working Group on Global Extractivisms and Alternatives, who jointly constructed this article. Equal authorship by all authors is recognised.Research on extractivism has rapidly proliferated, expanding into new empirical and conceptual spaces. We examine the origins, evolution, and conceptual expansion of the concept. Extractivism is useful to analyze resource extraction practices around the world. ‘Global Extractivism’ is a new conceptual tool for assessing global phenomena. We situate extractivism within an ensemble of concepts, and explore its relation to development, the state, and value. Extractivism as an organizing concept addresses many fields of research. Extractivism forms a complex of self-reinforcing practices, mentalities, and power differentials underwriting and rationalizing socio-ecologically destructive modes of organizing life-through subjugation, depletion, and non-reciprocity.Peer reviewe

Key principle of the efficient running, swimming, and flying

Empirical observations indicate striking similarities among locomotion in terrestrial animals, birds, and fish, but unifying physical grounds are lacking. When applied to efficient locomotion, the analytical mechanics principle of minimum action yields two patterns of mechanical similarity via two explicit spatiotemporal coherent states. In steady locomotory modes, the slow muscles determining maximal optimum speeds maintain universal intrinsic muscular pressure. Otherwise, maximal speeds are due to constant mass-dependent stiffness of fast muscles generating a uniform force field, exceeding gravitation. Being coherent in displacements, velocities and forces, the body appendages of animals are tuned to natural propagation frequency through the state-dependent elastic muscle moduli. Key words: variational principle of minimum action (04.20.Fy), locomotion (87.19.ru), biomechanics (87.85.G-).Comment: Submitted to the Europhysical Letter

Putative risk alleles for LATE-NC with hippocampal sclerosis in population-representative autopsy cohorts

Limbic-predominant age-related TAR-DNA-binding protein-43 (TDP-43) encephalopathy with hippocampal sclerosis pathology (LATE-NC + HS) is a neurodegenerative disorder characterized by severe hippocampal CA1 neuron loss and TDP-43-pathology, leading to cognitive dysfunction and dementia. Polymorphisms in GRN, TMEM106B and ABCC9 are proposed as LATE-NC + HS risk factors in brain bank collections. To replicate these results in independent population-representative cohorts, hippocampal sections from brains donated to three such studies (Cambridge City over 75-Cohort [CC75C], Cognitive Function and Ageing Study [CFAS], and Vantaa 85+ Study) were stained with hematoxylin-eosin (n = 744) and anti-pTDP-43 (n = 713), and evaluated for LATE-NC + HS and TDP-43 pathology. Single nucleotide polymorphism genotypes in GRN rs5848, TMEM106B rs1990622 and ABCC9 rs704178 were determined. LATE-NC + HS (n = 58) was significantly associated with the GRN rs5848 genotype (chi(2)(2) = 20.61, P <0.001) and T-allele (chi(2)(1) = 21.04, P <0.001), and TMEM106B rs1990622 genotype (Fisher's exact test, P <0.001) and A-allele (chi(2)(1) = 25.75, P <0.001). No differences in ABCC9 rs704178 genotype or allele frequency were found between LATE-NC + HS and non-LATE-NC + HS neuropathology cases. Dentate gyrus TDP-43 pathology associated with GRN and TMEM106B variations, but the association with TMEM106B nullified when LATE-NC + HS cases were excluded. Our results indicate that GRN and TMEM106B are associated with severe loss of CA1 neurons in the aging brain, while ABCC9 was not confirmed as a genetic risk factor for LATE-NC + HS. The association between TMEM106B and LATE-NC + HS may be independent of dentate TDP-43 pathology.Peer reviewe

Filled pauses in Hungarian: Their phonetic form and function

Filled pauses are natural occurrences in spontaneous speech and they may turn up at any level of the speech planning process and in a number of functions. The aim of this paper is to find out whether the diverse functions of filled pauses correlate with diverse articulations resulting in diverse acoustic structures. Spontaneous narratives are used as research material. The duration of the filled pauses and the frequency values of their first two formants are analyzed. The most frequent form, schwa, shows function-dependent realizations as confirmed by the durational values and by the second formant values of these vowel-like sounds

Growing up with cancer: Accommodating the effects of cancer into young people’s social lives.

Adolescence and young adulthood are transitional periods of rapid and dramatic personal change. Few events can cause as unpredictable and challenging alterations to this process as the onset of a serious illness, such as cancer. Although we know much about the physical and psychological consequences of having cancer at this time, we know little about the effect of cancer on young people’s relationships. We conducted interviews with 15 women and 12 men aged between 16 and 29 years, who had survived cancer. Our findings demonstrate that the experience of cancer and how it affects relationships is complex. It arrests young people’s development by increasing their dependence on parents, giving them life experiences unavailable to peers, and complicating the process of establishing new relationships. However, it also accelerates development by facilitating closer and more mature relationships with parents and giving young people wisdom and insight not shared by peers. Cancer profoundly shapes how young people conduct their relationships. These changes require ongoing accommodation by young people with cancer, their parents, peers, and new acquaintances