Formation of Quantum Phase Slip Pairs in Superconducting Nanowires

Macroscopic quantum tunneling (MQT) is a fundamental phenomenon of quantum mechanics related to the actively debated topic of quantum-to-classical transition. The ability to realize MQT affects implementation of qubit-based quantum computing schemes and their protection against decoherence. Decoherence in qubits can be reduced by means of topological protection, e.g. by exploiting various parity effects. In particular, paired phase slips can provide such protection for superconducting qubits. Here, we report on the direct observation of quantum paired phase slips in thin-wire superconducting loops. We show that in addition to conventional single phase slips that change superconducting order parameter phase by $2\pi$, there are quantum transitions changing the phase by $4\pi$. Quantum paired phase slips represent a synchronized occurrence of two macroscopic quantum tunneling events, i.e. cotunneling. We demonstrate the existence of a remarkable regime in which paired phase slips are exponentially more probable than single ones

Negative Link Prediction in Social Media

Signed network analysis has attracted increasing attention in recent years. This is in part because research on signed network analysis suggests that negative links have added value in the analytical process. A major impediment in their effective use is that most social media sites do not enable users to specify them explicitly. In other words, a gap exists between the importance of negative links and their availability in real data sets. Therefore, it is natural to explore whether one can predict negative links automatically from the commonly available social network data. In this paper, we investigate the novel problem of negative link prediction with only positive links and content-centric interactions in social media. We make a number of important observations about negative links, and propose a principled framework NeLP, which can exploit positive links and content-centric interactions to predict negative links. Our experimental results on real-world social networks demonstrate that the proposed NeLP framework can accurately predict negative links with positive links and content-centric interactions. Our detailed experiments also illustrate the relative importance of various factors to the effectiveness of the proposed framework

A brief note on the human visceral skeleton - An evolutionary perspective

A review of the visceral skeleton whose origin is in the branchial arches is reported here. It refers to bones, muscles and ligaments of relevant anatomical areas (ear ossicles, basicranium and mandible). The phylogenetic role of visceral skeleton components in the classification of prehistoric human remains has been analyzed by many scholars. It seems that the large morphological variation of these components among human groups makes their taxonomic significance questionable.Cette contribution porte sur le squelette viscéral qui, trouvant son origine dans les arcs branchiaux, concerne os, muscles et ligaments de différentes régions anatomiques (osselets de l’oreille moyenne, basicranium et mandibule). Le rôle phylogénétique de ces différents composants dans la classification des fossiles humains a été analysé par plusieurs auteurs. La grande variation morphologique qui affecte ces composants interpelle quant à leur utilisation à des fins d’analyse taxinomique

Adaptive Changes in Basal Metabolic Rate in Humans in Different Eco-Geographical Areas

Our aim was to establish whether the human basal metabolic rate (BMR) shifts towards the reduction of vital functions as an adaptation response to extreme environmental conditions. Data was collected in arid and Extreme North zones. The arid zone samples included Bedouins living in the Sinai Peninsula in Egypt, Turkmen students, the Pedagogical University of Chardzhou, Turkmenistan born Russians and Russian soldiers. Soldiers were divided into 3 groups according to the length of their tour of duty in the area: 1st group: up to six months, 2nd group: up to 2 years and the 3rd group: 3-5 years. The Extreme North samples comprised Chukchi natives, 1st generation Russian immigrants born in the area and 3 groups of soldiers comparable to the soldiers from Turkmenistan. BMR values of the new recruits had the highest values of total and relative BMR (1769±16 and 28.3±0.6, correspondingly). The total and relative BMR tended to decrease within a longer adaptation period. The BMR values of officers who served >3 years in Turkmenistan were very similar to the Turkmenistan born Russians (1730±14 vs. 1726±18 and 26.5±0.6 vs. 27.3±0.7, correspondingly). Similarly, in Chukotka, the highest relative BMR was found in the new recruits, serving up to 6 months (28.1±0.7) and was significantly (p3 years, compared to the middle-aged Chukchi or Chukotka-born Russians (25.8±0.5 vs. 25.6±0.5 and 25.5±0.6, correspondingly). The BMR parameters demonstrated a stronger association with body weight than with age. In extreme environmental conditions, migrant populations showed a decrease in BMR, thus reducing its vital functions. The BMR reduction effect with the adequate adaptive transformation is likely to be the key strategy for developing programs to facilitate human and animal adaptation to extreme factors. This process is aimed at preserving the optimum energy balance and homeostasis while minimizing stress on the body’s vital functions

: une note brève sur le squelette viscéral dans une perspective évolutive

National audienceA review of the visceral skeleton whose origin is in the branchial arches is reported here. It refers to bones, muscles and ligaments of relevant anatomical areas (ear ossicles, basicranium and mandible). The phylogenetic role of visceral skeleton components in the classification of prehistoric human remains has been analyzed by many scholars. It seems that the large morphological variation of these components among human groups makes their taxonomic significance questionable.Cette contribution porte sur le squelette viscéral qui, trouvant son origine dans les arcs branchiaux, concerne os, muscles et ligaments de différentes régions anatomiques (osselets de l'oreille moyenne, basicranium et mandibule). Le rôle phylogénétique de ces différents composants dans la classification des fossiles humains a été analysé par plusieurs auteurs. La grande variation morphologique qui affecte ces composants interpelle quant à leur utilisation à des fins d'analyse taxinomique

Morpho-Physiological Features of Human Populations in the Context of Climatic – Geographical Conditions

This paper is based on the data obtained in the course of population studies conducted in 33 geographical regions of the former USSR territory by the faculty of the Anuchin Research Institute and Museum of Anthropology, Lomonosov Moscow State University, between 1961 and 1991. The data resulting from study of 4386 male and 4626 female subjects aged 17 to 99 include head and body morphology, bone mineral density, blood oxygen saturation and blood biochemistry. We aimed at studying the link between the traits of a population and the climatic conditions of the area inhabited by this population. Individual characteristics of the subjects were normalized by age and sex, and factor analysis was used to reduce the number of cross-correlating features. As a result, several integral characteristics (factors) were identified: five body morphology-related factors, two headmorphology-related factors, one bone mineral density-related factor, one blood oxygen saturation-related factor and three blood biochemistry-related factors. These factors explained 79.3%, 78.38%, 63.51%, 74.4% and 66.77% of the trait groups’ variability, respectively. The correlation analysis between these factors and climatic indicators demonstrated that chest dimensions were the least tolerant to the climatic conditions among the morphological characteristics studied. Hemoglobin-protein ratios, as well as the factor that includes total cholesterol, were the most climate-dependent among the biochemical parameters. As far as our data show, blood serum oxygen saturation – the key factor determining the performance of the cardiovascular and respiratory systems – is also climate-dependent

Muscle β1D Integrin Reinforces the Cytoskeleton–Matrix Link: Modulation of Integrin Adhesive Function by Alternative Splicing

Expression of muscle-specific β1D integrin with an alternatively spliced cytoplasmic domain in CHO and GD25, β1 integrin-minus cells leads to their phenotypic conversion. β1D-transfected nonmuscle cells display rounded morphology, lack of pseudopodial activity, retarded spreading, reduced migration, and significantly enhanced contractility compared with their β1A-expressing counterparts. The transfected β1D is targeted to focal adhesions and efficiently displaces the endogenous β1A and αvβ3 integrins from the sites of cell–matrix contact. This displacement is observed on several types of extracellular matrix substrata and leads to elevated stability of focal adhesions in β1D transfectants. Whereas a significant part of cellular β1A integrin is extractable in digitonin, the majority of the transfected β1D is digitonin-insoluble and is strongly associated with the detergent-insoluble cytoskeleton. Increased interaction of β1D integrin with the actin cytoskeleton is consistent with and might be mediated by its enhanced binding to talin. In contrast, β1A interacts more strongly with α-actinin, than β1D. Inside-out driven activation of the β1D ectodomain increases ligand binding and fibronectin matrix assembly by β1D transfectants. Phenotypic effects of β1D integrin expression in nonmuscle cells are due to its enhanced interactions with both cytoskeletal and extracellular ligands. They parallel the transitions that muscle cells undergo during differentiation. Modulation of β1 integrin adhesive function by alternative splicing serves as a physiological mechanism reinforcing the cytoskeleton– matrix link in muscle cells. This reflects the major role for β1D integrin in muscle, where extremely stable association is required for contraction