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The Zhuangzi Au deposit in the world-class Jiaodong gold province hosts visible natural gold, and pyrite as the main ore mineral, making it an excellent subject for deciphering the complex hydrothermal processes and mechanisms of gold precipitation. Three types of zoned pyrite crystals were distinguished based on textural and geochemical results from EPMA, SIMS sulfur isotopic analyses and NanoSIMS mapping. Py0 has irregular shapes and abundant silicate inclusions and was contemporaneous with the earliest pyrite–sericite–quartz alteration. It has low concentrations of As (0–0.3 wt.%), Au and Cu. Py1 precipitated with stage I mineralization shows oscillatory zoning with the bright bands having high As (0.4–3.9 wt.%), Au and Cu contents, whereas the dark bands have low contents of As (0–0.4 wt.%), Au and Cu. The oscillatory zoning represents pressure fluctuations and repeated local fluid phase separation around the pyrite crystal. The concentration of invisible gold in Py1 is directly proportional to the arsenic concentration. Py1 is partially replaced by Py2 which occurs with arsenopyrite, chalcopyrite and native gold in stage II. The replacement was likely the result of pseudomorphic dissolution–reprecipitation triggered by a new pulse of Au-rich hydrothermal fluids. The δ34S values for the three types of pyrite are broadly similar ranging from + 7.1 to + 8.8‰, suggesting a common sulfur source. Fluid inclusion microthermometry suggests that extensive phase separation was responsible for the gold deposition during stage II mineralization. Uranium–Pb dating of monazite constrains the age of mineralization to ca. 119 Ma coincident with a short compressional event around 120 Ma linked to an abrupt change in the drift direction of the subducting Pacific plate.

The Daliuhang gold deposit (> 20 t gold) is located in the central Penglai-Qixia belt of the giant Jiaodong gold province, eastern China. The ore-hosting Guojialing granodiorite and pegmatite were formed at 129.0 ± 0.6 Ma and 126.2 ± 0.6 Ma, respectively. Syn-ore monazite, with a U–Pb age of 120.5 ± 1.7 Ma, represents the timing of gold mineralization. Given at least 5 m.y. between magmatism and mineralization, a genetic relationship to magmatic-hydrothermal activity is negated. Noble gas isotopes of pyrite have crust-mantle-mixed 3He/4He (1.13 to 1.50 Ra) and air-like 40Ar/36Ar (327–574). Together with the broadly positive correlation between 3He and 36Ar, it is inferred that the initial ore-forming fluids were deeply sourced from the sedimentary wedge overlying the subducted plate and overlying mantle during early Cretaceous paleo-Pacific plate subduction. The pre-ore and post-ore pyrites have low δ34S values (3.7–5.6‰ and 5.3–6.4‰, respectively), whereas ore-related pyrites have higher δ34S values, especially in As–Au-rich domains (7.8–8.3‰). These positive δ34S values also suggest that the initial ore fluid and some of the sulfur component were derived via subduction-related devolatilization. The elevated δ34S values of the ore-related pyrite are partly ascribed to mass fractionation and partly to a contribution from sulfur leached from crustal host rocks. This interpretation is also supported by neodymium isotope ratios of monazite (εNd (~ 120 Ma) = − 13.7 to − 11.6), which correlate well with the ore-hosting Guojialing granodiorite. This study highlights the combined roles of deeply derived fluids and intense interaction with upper crustal rocks in the formation of Jiaodong gold deposits.

Objective To evaluate the efficacy of wearable transcutaneous electrical nerve stimulation (TENS) combined with transcranial direct current stimulation (tDCS) in the middle-aged person with mild knee osteoarthritis (KOA). Design Double-blind, randomized clinical trial. Setting A general hospital. Subjects Participants aged 60–70 with mild KOA (Kellgren–Lawrence grade 1–2). Interventions The experimental group received TENS + tDCS, and the control group received TENS + sham tDCS for four weeks from Monday through Friday. Main measures The primary outcome was Brief Pain Inventory (BPI). The secondary outcomes included participants’ Visual Analog Scale (VAS), step length, cadence, 6-minute walking test (6MWT), active knee range of motion (ROM), and quadriceps strength. The indexes were assessed one week before treatment (T0), two weeks after treatment commencement (T1), four weeks after treatment commencement (T2), one month after treatment cessation (T3), and two months after treatment cessation (T4). Results A total of 110 participants (55 per group) completed the intervention and follow-up. Repeated-measures ANOVA indicated that tDCS significantly improved the efficacy of TENS in alleviating pain and enhancing walking ability among patients with mild KOA. Statistically significant differences in BPI scores were observed between the experimental and control groups at T1 (2.16 vs. 2.45, P  = 0.038), T2 (1.17 vs. 1.73, P  < 0.001), and T3 (2.17 vs. 2.41, P  = 0.021). However, no significant difference was detected at T4 (2.50 vs. 2.63, P  = 0.293). Conclusion The four-week combined intervention demonstrated that tDCS potentiated the therapeutic efficacy of TENS in managing mild KOA. The combined protocol exhibited superiority over TENS monotherapy, with sustained benefits observed up to one-month post-intervention. Trial registration This research has been registered in chictr.org.cn (registration number: ChiCTR2200064735) on 15 October 2022, https://www.chictr.org.cn/showproj.html?proj=182561 .

Transcranial direct current stimulation (tDCS) and transcutaneous electrical nerve stimulation (TENS) are both recognized for their analgesic effects; however, evidence suggests limitations in their efficacy when applied to knee osteoarthritis (KOA) after stroke. This study aimed to assess the efficacy and cortical activity impact of a dual‐target electrical stimulation approach combining tDCS and TENS in the treatment of KOA after stroke. We hypothesized that the combination of tDCS with TENS could more effectively address KOA after stroke by enhancing brain activity through the induction of neural oscillations. To test this hypothesis, a double‐blind, randomized trial was conducted with 30 participants receiving either TENS + tDCS or TENS + sham tDCS over an 8‐week period, from Monday to Friday. Electroencephalograms (EEGs), Brief Pain Inventory (BPI), visual analog scale (VAS), stride length, cadence, 6‐min walk test (6 MWT), knee range of motion (ROM), and quadriceps strength were collected pre‐ and poststimulation. Pain indicators were analyzed using t ‐tests for continuous variables and chi‐square tests for categorical variables, with repeated measures ANOVA employed to explore changes and interactions over time. For EEG analysis, paired t ‐tests were utilized to investigate changes in brain regions before and after treatment on the affected side, with visual analysis conducted subsequently. The results indicated that the combined treatment led to significant improvements in the affected hemisphere, with significant changes observed in α1, α2, and β power. Additionally, significant group× time interaction effects were noted for BPI, VAS, stride length, cadence, and 6MWT. The study concludes that dual‐target electrostimulation using tDCS combined with TENS significantly ameliorates knee joint inflammation following stroke by acting on the cerebral cortex and target organs. Trial Registration: Chinese Clinical Trial Registry: ChiCTR2200064735

Winged fruits possess a unique flight mechanism relying on simple geometric structures rather than neuromuscular control. This study proposes an innovative approach using origami techniques to create three-winged model fruits, serving as a proxy for understanding the flight dynamics of natural winged fruits. Paper is employed to simulate inherent wing flexibility, with the option to add plastic frames for rigidity. We comprehensively investigate the free fall motion of both rigid and flexible winged fruits through experimental and numerical analyses. Velocity–time curves reveal a three-stage descent pattern—acceleration, deceleration, and steady states. The overshoot phenomenon is attributed to rapid lift increase due to leading-edge vortices attaching stably to the wings. This insight sheds light on aerodynamics governing fruit flight. Compared with rigid wings, flexible wings exhibit two key properties—slower descent and higher self-orienting capability—that facilitate a more stable and longer-distance dispersal of seeds under crosswind conditions. Our study demonstrates the potential benefits of flexible wings in natural seed distribution. This study advances our understanding of winged fruit flight dynamics, utilizing origami as a powerful tool for biomimetic investigations. The findings have broad implications, from improving aerodynamic designs to developing efficient micro air vehicles and electronic microfliers, and understanding seed dispersal evolution. Graphical abstract

Date Presented 4/1/2017 This study explores smartphone use in undergraduate students’ self-directed learning. The factors were identified, providing an understanding of how undergraduate students could be more motivated and effective in their short-term, self-directed learning under the influence of smartphone use. Primary Author and Speaker: Ya-chun Chang Additional Authors and Speakers: Kuan-Chen Chen, Wen Ting Chen, Ya-syuan Cai Contributing Authors: Chang-Chih Robin Kuo

Margin trading in which investors purchase shares with money borrowed from brokers is blamed to be a major cause of the 2015 Chinese stock market crash. We propose a cascading failure model and examine how an increase in margin trading increases share price vulnerability. The model is based on a bipartite graph of investors and shares that includes four margin trading factors, (i) initial margin \\(k\\), (ii) minimum maintenance \\(r\\), (iii) volatility \\(v\\), and (iv) diversity \\(s\\). We use our model to simulate margin trading and observe how the share prices are affected by these four factors. The experimental results indicate that a stock market can be either vulnerable or stable. A stock market is vulnerable when an external shock can cause a cascading failure of its share prices. It is stable when its share prices are resilient to external shocks. Furthermore, we investigate how the cascading failure of share price is affected by these four factors, and find that by increasing \\(v\\) and \\(r\\) or decreasing \\(k\\) we increase the probability that the stock market will experience a phase transition from stable to vulnerable. It is also found that increasing \\(s\\) decreases resilience and increases systematic risk. These findings could be useful to regulators supervising margin trading activities.

In a stock market, the price fluctuations are interactive, that is, one listed company can influence others. In this paper, we seek to study the influence relationships among listed companies by constructing a directed network on the basis of Chinese stock market. This influence network shows distinct topological properties, particularly, a few large companies that can lead the tendency of stock market are recognized. Furthermore, by analyzing the subnetworks of listed companies distributed in several significant economic sectors, it is found that the influence relationships are totally different from one economic sector to another, of which three types of connectivity as well as hub-like listed companies are identified. In addition, the rankings of listed companies obtained from the centrality metrics of influence network are compared with that according to the assets, which gives inspiration to uncover and understand the importance of listed companies in the stock market. These empirical results are meaningful in providing these topological properties of Chinese stock market and economic sectors as well as revealing the interactively influence relationships among listed companies.

A mass of traces of human activities show rich dynamic patterns. In this article, we comprehensively investigate the dynamic patterns of 50 thousands of researchers' activities in Sciencenet, the largest multi-disciplinary academic community in China. Through statistical analyses, we found that (i) there exists a power-law scaling between the frequency of visits to an academic forum and the number of corresponding visitors, with the exponent being about 1.33; (ii) the expansion process of academic forums obeys the Heaps' law, namely the number of distinct visited forums to the number of visits grows in a power-law form with exponent being about 0.54; (iii) the probability distributions of time intervals and the number of visits taken to revisit the same academic forum both follow power-laws, indicating the existence of memory effect in academic forum activities. On the basis of these empirical results, we propose a dynamic model that incorporates the exploration, preferential return and memory effect, which can well reproduce the observed scaling laws.

The financial market and turbulence have been broadly compared on account of the same quantitative methods and several common stylized facts they shared. In this paper, the She-Leveque (SL) hierarchy, proposed to explain the anomalous scaling exponents deviated from Kolmogorov monofractal scaling of the velocity fluctuation in fluid turbulence, is applied to study and quantify the hierarchical structure of stock price fluctuations in financial markets. We therefore observed certain interesting results: (i) The hierarchical structure related to multifractal scaling generally presents in all the stock price fluctuations we investigated. (ii) The quantitatively statistical parameters that describes SL hierarchy are different between developed financial markets and emerging ones, distinctively. (iii) For the high-frequency stock price fluctuation, the hierarchical structure varies with different time period. All these results provide a novelty analogy in turbulence and financial market dynamics and a insight to deeply understand the multifractality in financial markets.