Long range dipole-dipole interaction in low-density atomic vapors probed by double-quantum two-dimensional coherent spectroscopy

Optical double-quantum two-dimensional coherent spectroscopy (2DCS) was implemented to probe interatomic dipole-dipole interactions in both potassium and rubidium atomic vapors. The dipole-dipole interaction was detected at densities of $4.81 \times 10^8$ cm$^{-3}$ and $8.40 \times 10^9$ cm$^{-3}$ for potassium and rubidium, respectively, corresponding to a mean interatomic separation of 15.8 $\mu$m or $3.0\times 10^5a_0$ for potassium and 6.1 $\mu$m or $1.2\times 10^5a_0$ for rubidium, where $a_0$ is the Bohr radius. We report the lowest atomic density at which dipole-dipole interactions are detected. The experimental results confirm the long range nature of the dipole-dipole interaction which is critical for understanding many-body physics in atoms/molecules. The long range interaction also has implications in atom-based applications involving many-body interactions. Additionally, we demonstrated that double-quantum 2DCS is sufficiently sensitive to probe dipole-dipole interaction at densities that can be achieved with cold atom in a magneto-optical trap, paving the way for double-quantum 2DCS studies of cold atoms and molecules. The method can also open a new avenue to study long-range interactions in solid states systems such as quantum dots and color centers in diamonds.Comment: 5 pages, 4 figure

Genomic imprinting defect in Zfp57 mutant iPS cell lines

AbstractZFP57 maintains genomic imprinting in mouse embryos and ES cells. To test its roles during iPS reprogramming, we derived iPS clones by utilizing retroviral infection to express reprogramming factors in mouse MEF cells. After analyzing four imprinted regions, we found that parentally derived DNA methylation imprint was largely maintained in the iPS clones with Zfp57 but missing in those without maternal or zygotic Zfp57. Intriguingly, DNA methylation imprint was lost at the Peg1 and Peg3 but retained at the Snrpn and Dlk1-Dio3 imprinted regions in the iPS clones without zygotic Zfp57. This finding will be pursued in future studies

Learning Geometry-Dependent and Physics-Based Inverse Image Reconstruction

Deep neural networks have shown great potential in image reconstruction problems in Euclidean space. However, many reconstruction problems involve imaging physics that are dependent on the underlying non-Euclidean geometry. In this paper, we present a new approach to learn inverse imaging that exploit the underlying geometry and physics. We first introduce a non-Euclidean encoding-decoding network that allows us to describe the unknown and measurement variables over their respective geometrical domains. We then learn the geometry-dependent physics in between the two domains by explicitly modeling it via a bipartite graph over the graphical embedding of the two geometry. We applied the presented network to reconstructing electrical activity on the heart surface from body-surface potential. In a series of generalization tasks with increasing difficulty, we demonstrated the improved ability of the presented network to generalize across geometrical changes underlying the data in comparison to its Euclidean alternatives

The effect of parenting styles on Chinese undergraduate nursing students’ academic procrastination: the mediating role of causal attribution and self-efficacy

BackgroundAcademic procrastination is common among college students, but there is a lack of research on the influencing mechanism of academic procrastination among nursing students. The purpose of this study was to explore the influence of parental rearing patterns on academic procrastination of nursing students, and the mediating role of causal attribution and self-efficacy.MethodsUsing Parental Bonding Instrument, Aitken Procrastination Inventory, Multidimensional Multi-Attribution Causality Scale and General Self-Efficiency Scale, the data of 683 nursing undergraduates from two universities in China were collected. Moreover, path analysis for structural equation modeling via AMOS 26.0 to evaluate mediation path model.ResultsPositive parenting style was negatively associated with academic procrastination (r = –0.350) and negative parenting style was positively associated with academic procrastination (r = 0.402). Positive parenting style directly or indirectly predicted academic procrastination through the mediating effect of internal attributional style (β = –0.10, 95% CI: –0.18 to –0.04) and self-efficacy (β = –0.07, 95% CI: –0.11 to –0.03), and this mediating effect accounted for 41.46% of the total effect. Positive parenting style directly or indirectly predicted academic delay through the mediating effect of external attributional style (β = 0.12, 95% CI: 0.07 to 0.17) and self-efficacy (β = 0.05, 95% CI: 0.03 to 0.08), and this mediating effect accounted for 42.5% of the total effect. In addition, causal attribution and self-efficacy of nursing students play a chain intermediary role between parenting style and academic procrastination.ConclusionParents should give students more care and autonomy and reduce control. In addition, educators should give students attribution training, which is helpful to improve students’ self-efficacy and reduce academic procrastination

The role of taurine in male reproduction: Physiology, pathology and toxicology

Taurine, a sulfur-containing amino acid, has a wide range of biological effects, such as bile salt formation, osmotic regulation, oxidative stress inhibition, immunomodulation and neuromodulation. Taurine has been proved to be synthesized and abundant in male reproductive organs. Recently, accumulating data showed that taurine has a potential protective effect on reproductive function of male animals. In physiology, taurine can promote the endocrine function of the hypothalamus-pituitary-testis (HPT) axis, testicular tissue development, spermatogenesis and maturation, delay the aging of testicular structure and function, maintain the homeostasis of the testicular environment, and enhance sexual ability. In pathology, taurine supplement may be beneficial to alleviate pathological damage of male reproductive system, including oxidative damage of sperm preservation in vitro, testicular reperfusion injury and diabetes -induced reproductive complications. In addition, taurine acts as a protective agent against toxic damage to the male reproductive system by exogenous substances (e.g., therapeutic drugs, environmental pollutants, radiation). Related mechanisms include reduced oxidative stress, increased antioxidant capacity, inhibited inflammation and apoptosis, restored the secretory activity of the HPT axis, reduced chromosomal variation, enhanced sperm mitochondrial energy metabolism, cell membrane stabilization effect, etc. Therefore, this article reviewed the protective effect of taurine on male reproductive function and its detailed mechanism, in order to provide reference for further research and clinical application