Über die Existenz einer unbekannten natürlichen α-Aktivität im 4,3 – 4,6 MeV-Bereich

Abstract

Purpose. Female runners are known to be at greater risk from chronic running injuries than age-matched males, although the exact mechanisms are often poorly understood. The aim of the current investigation was to determine if female recreational runners exhibit distinct limb and joint stiffness characteristics in relation to their male counterparts. Methods. Fourteen male and fourteen female runners ran over a force platform at 4.0 m · s -1 . Lower limb kinematics were collected using an eight-camera optoelectric motion capture system operating at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. All stiffness and joint moment parameters were normalized to body mass. Sex differences in normalized limb and knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that normalized limb (male = 0.18 ± 0.07, female = 0.37 ± 0.10 kN · kg · m -1 ) and knee stiffness (male = 5.59 ± 2.02, female = 7.34 ± 1.78 Nm · kg · rad -1 ) were significantly greater in female runners. Conclusions. On the basis that normalized knee and limb stiffness were shown to be significantly greater in female runners, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between sexes.

The possible existence of Hs in nature from a geochemical point of view

“…The isotopes 271 Bh, 271 Hs, 267 Sg, 267 Db, and 263 Lr have not yet been produced experimentally, which is why the decay chains (3), (4), and (5) seem highly hypothetical. Thus, the idea of the presence of Hs long-lived isotopes in some natural objects [2][3][4] associated with the observed excess activity of 235 U, 239 Pu, and unidentified ~4.4-MeV 〈 activity in various natural samples cannot be accepted without additional assumptions. In view of the fact that the data of the papers [2-4, 10, 11] were not verified experimentally, such a check is the barest necessity.…”

“…The aim of these calculations was to fit the theoretical data to the indications of ~4. 4 MeV α activity experimentally found in some natural objects [2][3][4]. The possibility of Hs occurring in molybdenite and osmiride, in which this excess α activity was observed [2,4], is considered from a geochemical point of view in the present paper.…”

“…4 MeV α activity experimentally found in some natural objects [2][3][4]. The possibility of Hs occurring in molybdenite and osmiride, in which this excess α activity was observed [2,4], is considered from a geochemical point of view in the present paper. The problem of the existence of long-lived superheavy elements is discussed from the standpoint of theoretical and experimental physics, among other papers, in [5][6][7][8][9].…”

“…Later works were aimed at the identification of this transuranium element with the use of the α -spectroscopic method. In papers [2][3][4] in natural samples of different age and genesis (bone fossils, magmatic minerals, iron meteorite, etc.) unidentified α activity in the energy range from 4.2-4.6 MeV was observed, as well as the presence of an energy spectrum identified with 239Pu was recognized.…”

“…The chemical properties of the transuranium element were similar to osmium [3]. Different fractions of osmiridium after chemical sample preparation were analyzed, as well as αactivity of energy 4.4 MeV was revealed in [4]. To account for the observed phenomenon, it was suggested that there possibly exists a long-lived superheavy element with the chemical properties of osmium, now known as hassium (Hs, element 108).…”