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In this paper, we extend the reinterpreted discrete fracture model for flow simulation of fractured porous media containing flow blocking barriers on non-conforming meshes. The methodology of the approach is to modify the traditional Darcy's law into the hybrid-dimensional Darcy's law where fractures and barriers are represented as Dirac-delta functions contained in the permeability tensor and resistance tensor, respectively. As a natural extension of the reinterpreted discrete fracture model for highly conductive fractures, this model is able to account for the influence of both highly conductive fractures and blocking barriers accurately on non-conforming meshes. The local discontinuous Galerkin (LDG) method is employed to accommodate the form of the hybrid-dimensional Darcy's law and the nature of the pressure/flux discontinuity. The performance of the model is demonstrated by several numerical tests.

The development of artificial intelligent composition has resulted in the increasing popularity of machine-generated pieces, with frequent copyright disputes consequently emerging. There is an insufficient amount of research on the judgement of artificial and machine-generated works; the creation of a method to identify and distinguish these works is of particular importance. Starting from the essence of the music, the article constructs a music-rule-identifying algorithm through extracting modes, which will identify the stability of the mode of machine-generated music, to judge whether it is artificial intelligent. The evaluation datasets used are provided by the Conference on Sound and Music Technology(CSMT). Experimental results demonstrate the algorithm to have a successful distinguishing ability between datasets with different source distributions. The algorithm will also provide some technological reference to the benign development of the music copyright and artificial intelligent music.

The US government is gradually shifting the full retirement age in Social Security to age 67. However, previous studies suggest that this shift could negatively impact the mental and physical health of retirees. To understand the potential impact of raising the full retirement age on the functional health of retirees, this longitudinal study examined changes in physical functioning over time in retirees by age at retirement. Twelve waves of the Health and Retirement Study (1994 – 2018) were used. A total of 8,261 retirees was included. The retirement age was a categorical variable: very early age (67). Physical functioning was measured using 15 Activities of Daily Living and Instrumental Activities of Daily Living. A GEE model was used to assess the relationship between the retirement age category and the number of functional limitations. In the adjusted model, after controlling for all the other variables including baseline health and functioning, late retirement was associated with an 8.9% increased risk of functional limitations compared to traditional age retirement (IRR: 0.91, 95% CI:0.84 –0.98). Compared to late retirees, the risk of functional limitations was increased by 28.6% in very early age retirees (IRR: 1.29, 95% CI:1.21–1.36). Compared to those retiring at traditional retirement age, those retiring late, after 67, have increased the risks of functional limitations. Although levels of disability could influence age of retirement, these results suggest that for some workers efforts to increase age of full retirement, could have negative effects.

Metastasis accounts for the vast majority of cancer deaths. To minimize metastasis-associated mortality, it is crucially important to evaluate the metastatic potential (M.P.), that is, defined as a tendency of a primary tumor to colonize a distant organ. Dysregulated pH in solid tumors, especially the acidification of extracellular pH (pHe ) promotes dormant metastasis by driving protease-mediated digestion, disrupting cell-matrix interaction and increasing migration of cancer cells. Therefore, imaging intratumoral acidosis creates a unique opportunity to evaluate the M.P. In this work, a novel pH activatable probe was developed, in which two near-infrared (NIR) fluorophores were conjugated via a flexible and acid liable linkage. While the fluorescence of this probe is quenched due to intramolecular dimeric aggregate under neutral environment, the cleavage of pH liable linkage with the concomitant disruption of aggregates in acidic tumor microenvironment results in a remarkable fluorescence enhancement. This probe not only visualized the primary tumors with high target to background (T/B) signal ratio in vivo, but also revealed the correlation between the M.P. and acidosis distribution pattern in tumor. While the acidosis locate dispersedly at tumor periphery in highly metastatic tumor, it distribute more widely in lowly metastatic tumor and the acidification degree increases substantially from the margin to core areas. This pH activatable NIR fluorescent probe holds the potential to evaluate the M.P., monitor the therapeutic response and predict the prognosis by delineating acidosis in tumors.