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The Jiadi gold deposit, situated in the Southwestern region of Guizhou, is a large-scale, recently discovered, basalt-hosted, and fine-grained disseminated gold deposit. This study has unveiled that the tectonic deformation of the Jiadi gold deposit can be categorized into four stages: the Late Paleozoic crustal uplift and brittle deformation (D1-deformation) stage; the Early Yanshanian NW-trending compressive ductile deformation (D2-deformation) stage; the Late Yanshanian NS-trending strike-slip fault (D3-deformation) stage; and the Himalayan EW-trending nappe structure (D4-deformation) stage. The outcomes of the C-O isotope analysis revealed that the fluid responsible for ore formation exhibits the attributes of magmatic water blended with meteoric water, and the metallogenic constituents primarily originate from a deep source. The formation of the Jiadi gold deposit occurred during the D2-deformation stage and extended to the D3-deformation stage. The D2-deformation stage induced hydrothermal activity and rock devolatilization, leading to the generation of CO2-rich and low-salinity fluids. The D3-deformation stage, which is intimately associated with mineralization, can be classified into three stages: the pyrite stage; the smoky quartz stage; and the sulfide stage. The findings obtained from laser Raman spectroscopy indicate that the inclusions typically comprise CO2, CH4, N2, and SO2. These deep fluids ascended along the fault to the interlayer fracture zone during the D3-deformation stage. The alteration of the geochemical environment was accompanied by fluid immiscibility or boiling, resulting in the rapid precipitation of metallogenic materials.

Quantum lock-in amplifier aims to extract an alternating signal within strong noise background by using quantum strategy. However, as the target signal usually has an unknown initial phase, we can't obtain the complete information of its amplitude, frequency and phase in a single lock-in measurement. Here, to overcome this challenge, we give a general protocol for achieving a quantum double lock-in amplifier and illustrate its realization. In analog to a classical double lock-in amplifier, our protocol is accomplished via two quantum mixers under orthogonal pulse sequences. The two orthogonal pulse sequences act the roles of two orthogonal reference signals in a classical double lock-in amplifier. Combining the output signals, the complete characteristics of the target signal can be obtained. As an example, we illustrate the realization of our quantum double lock-in amplifier via a five-level double-$\Lambda$ coherent population trapping system with $^{87}$Rb atoms, in which each $\Lambda$ structure acts as a quantum mixer and the two applied dynamical decoupling sequences take the roles of two orthogonal reference signals. Our numerical calculations show that the quantum double lock-in amplifier is robust against experimental imperfections, such as finite pulse length and stochastic noise. Our study opens an avenue for extracting complete characteristics of an alternating signal within strong noise background, which is beneficial for developing practical quantum sensing technologies.

Spin cat states are promising candidates for achieving Heisenberg-limited quantum metrology. It is suggested that spin cat states can be generated by adiabatic evolution. However, due to the limited coherence time, the adiabatic process may be too slow to be practical. To speed up the state generation, we propose to use machine optimization to generate desired spin cat states. Our proposed scheme relies only on experimentally demonstrated one-axis twisting interactions with piecewise time-modulation of rotations designed via machine optimization. The required evolution time is much shorter than the one with adiabatic evolution and it does not make large modification to the existing experimental setups. Our protocol with machine optimization is efficient and easy to be implemented in state-of-the-art experiments., 9 pages, 7 figures

Atomic spectroscopy, an essential tool for frequency estimation, is widely used in quantum sensing. Atom-atom interaction can be used to generate entanglement for achieving quantum enhanced sensing. However, atom-atom interaction always induces collision shift, which brings systematic error in determining the resonance frequency. Contradiction between utilizing atom-atom interaction and suppressing collision shift generally exists in atomic spectroscopy. Here, we propose an antisymmetric Rabi spectroscopy protocol without collision shift in the presence of atom-atom interactions. We analytically find that the antisymmetric point can be used for determining the resonance frequency. For small Rabi frequency, our antisymmetric Rabi spectroscopy with slight atom-atom interaction can provide better measurement precision than the conventional Rabi spectroscopy. With stronger atom-atom interaction and Rabi frequency, the spectrum resolution can be dramatically improved and the measurement precision may even beat the standard quantum limit. Moreover, unlike the quantum-enhanced Ramsey interferometry via spin squeezing, our scheme is robust against detection noises. Our antisymmetric Rabi spectroscopy protocol has promising applications in various practical quantum sensors such as atomic clocks and atomic magnetometers., Comment: 6 pages, 4 figures

The Yuqia uranium deposit is a newly discovered sandstone-type uranium deposit in the northern margin of the Qaidam Basin. Concerning the sources of sediment in the basin, most scholars have focused on the study of Cenozoic sediment sources in the northern part of the basin, rather than on the study of Jurassic provenance and its implications for uranium mineralization. In this paper, the Jurassic sandstones in the area were selected for petrography, petrogeochemistry and electron microprobe analysis (EPMA), and the significance of sedimentary provenance and uranium metallogeny were further discussed, based on the previous data of detrital zircon chronology. It is reported here for the first time that coffinite and pitchblende are the main contributors. Independent uranium minerals in the region mainly occur in strawberry pyrite, xenotime, and margins or of quartz. The rocks in the source area, Jurassic sandstones, were mainly formed under the tectonic setting of the active continental margin; however, the sediments are mainly derived from the Indosinian and Paleozoic granitoids exposed in the northern margin of the Qaidam Basin. The uranium-rich granites in the source area led to the preconcentration of uranium in the sandstone of the target layer, and the uranium was brought into the ore-bearing target layer through uranium-bearing oxygenated water. The reduction reaction occurred under the action of reducing matter, and finally, the U6+ was reduced to U4+ in the formation of coffinite and pitchblende.

Qinxin Liu,1 Hongxia Duan,1 Anbei Lian,1 Min Zhuang,1,2 Xianli Zhao,1 Xiaodan Liu1,3 1School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China; 2Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China; 3Engineering Research Center of Intelligent Rehabilitation of Traditional Chinese Medicine, Ministry of Education, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of ChinaCorrespondence: Xiaodan Liu; Xianli ZhaoSchool of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, ChinaTel +86-21-51323158Fax +86-21- 51323199Email hzhp403@126.com; zhaoxianli16@126.comIntroduction: Diaphragm dysfunction is a significant extrapulmonary effect in chronic obstructive pulmonary disease (COPD), which is manifested by changes in diaphragm structure and reduced diaphragm strength. Acupuncture is a traditional rehabilitation technique in China, which has been used in rehabilitation for COPD. But whether acupuncture can improve the diaphragm function of COPD patients remains to be verified.Objective: The objective of this study was to evaluate the rehabilitation effects of acupuncture on diaphragm dysfunction in patients with COPD.Methods: The authors retrieved in CNKI, VIP, SinoMed, PubMed, Ebsco, Web of Science, from inception to November 2020, for relevant randomized control trials. Two researchers independently screened the articles and extracted the data. The quality of the included studies was evaluated by Physiotherapy Evidence Database scale. The primary outcome measures were maximal inspiratory pressure and the scale for accessory respiratory muscle mobilization, the secondary outcome measures were pulmonary function-related indicators and arterial blood gas indicators.Results: Nine articles were finally obtained. Seven studies added acupuncture to standard treatment for patients with diaphragm dysfunction in COPD and found statistically significant changes in the maximum inspiratory pressure and the scale for accessory respiratory muscle mobilization. Two studies have proved that use acupuncture combined with other Traditional Chinese Medicine methods in the rehabilitation for COPD can effectively improve the diaphragm strength and diaphragmatic motor performance. Seven studies showed that acupuncture has obvious improvement in pulmonary ventilation function. Seven studies reported significant differences in arterial blood gas pre- to post-intervention.Conclusion: This systematic review found that acupuncture can effectively enhance the diaphragm strength, relieve respiratory muscle fatigue, it can also play a promoting role in improving lung function, hypoxia, and carbon dioxide retention, as well as preventing and alleviating respiratory failure. The generalizability of these results is limited by the design of the included studies.Keywords: chronic obstructive pulmonary disease, diaphragm, dysfunction, acupuncture, rehabilitation effect

Recent music tourism researches are notable owing to growing socioeconomic significance of music. But the question about how music affects tourists’ behaviors in travel practice remains there. This...

In this paper, we use a wireless sensor network data algorithm to optimize the design of mechanical chain drive by conducting an in-depth study of the mechanical chain drive optimization. We utilize the crowdsourcing feature of the swarm-wise sensing network for assisted wireless sensor networking to achieve crowdsourcing-assisted localization. We consider a framework for crowdsourcing-assisted GPS localization of wireless sensor networks and propose two recruitment participant optimization objectives, namely, minimum participants and time efficiency, respectively. A model and theoretical basis are provided for the subsequent trusted data-driven participant selection problem in swarm-wise sensing networks. The sprocket-chain engagement frequency has the greatest influence on the horizontal bending-vertical bending composite in different terrain conditions. The dynamic characteristics under working conditions are most influenced, while the scraping of the scraper and the central groove significantly influenced horizontal bending and vertical bending. Under load conditions, the amplitude of the scraper and central groove scraping increases significantly, which harm the dynamics of the scraper conveyor. By monitoring the speed difference between the head and tail sprockets and the overhang of the scraper, the tensioning status of the scraper conveyor chain can be effectively monitored to avoid chain jamming and chain breakage caused by the loose chain, thus improving the reliability and stability of the scraper conveyor.

Bayesian estimation approaches, which are capable of combining the information of experimental data from different likelihood functions to achieve high precisions, have been widely used in phase estimation via introducing a controllable auxiliary phase. Here, we present a non-adaptive Bayesian phase estimation (BPE) algorithms with an ingenious update rule of the auxiliary phase designed via active learning. Unlike adaptive BPE algorithms, the auxiliary phase in our algorithm is determined by a pre-established update rule with simple statistical analysis of a small batch of data, instead of complex calculations in every update trails. As the number of measurements for a same amount of Bayesian updates is significantly reduced via active learning, our algorithm can work as efficient as adaptive ones and shares the advantages (such as wide dynamic range and perfect noise robustness) of non-adaptive ones. Our algorithm is of promising applications in various practical quantum sensors such as atomic clocks and quantum magnetometers., Comment: 8 pages, 4 figures

In this study, 127 light-duty gasoline cars and 10 light-duty gasoline trucks with different emission standards were selected to explore the influences of different conditions and vehicle parameters on the emission characteristics of carbon dioxide (CO

Additional file 1: Figure S1. Infectivity and western blot of pseudoviruses bearing Env with mutations E560K/D/G. (a) Infectivity of pseudoviruses in U87CD4+CXCR4+ and RC4 cells. The relative luciferase infectivity is indicating that the ratio is IC50 for the indicated pseudovirus/LAIwt pseudovirus. The averages and SD values (error bars) of at least three independent experiments are shown. *p

Additional file 2: Table S1. Primer sequences for LAI mutant env creation.

Wave-particle duality, an important and fundamental concept established upon pure quantum systems, is central to the complementarity principle in quantum mechanics. However, due to the environment effects or even the entanglement between the quanton and the which-way detector (WWD), the quanton should be described by a mixed quantum state but not a pure quantum state. Although there are some attempts to clarify the complementarity principle for mixed quantum systems, it is still unclear how the mixedness affects the complementary relation. Here, we give a ternary complementary relation (TCR) among wave, particle and mixedness aspects for arbitrary multi-state systems, which are respectively quantified by the $l_1$ measure for quantum coherence, the which-path predictability, and the linear entropy. In particular, we show how a WWD can transform entropy into predictability and coherence. Through modifying the POVM (positive-operator valued measure) measurement on WWD, our TCR can be simplified as the wave-mixedness and particle-mixedness duality relations. Beyond enclosing the wave-particle duality relation [PRL 116, 160406 (2016)], our TCR relates to the wave-particle-entanglement complementarity relation [PRL 98, 250501 (2008); Opt. Commun. 283, 827 (2010)]., 5 + 4 pages, 2 + 2 figures

This paper proposes an approach to carry out sensitivity analysis of tool axis errors caused by component geometric errors, in order to meet the high precision requirement in holes series machining with mill-turn machine tools. Firstly, ideal kinematic model and real kinematic model considering geometric errors of the mill-turn machine tools are built respectively based on homogeneous transfer matrix and multi-body system theory. Secondly, tool axis errors caused by component geometric errors are simulated using an orthogonal test. Finally, sensitivity analysis of tool axis errors is implemented by means of range analysis and variance analysis.

Quantum metrology is the interdisciplinary of investigating how to utilize the principles of quantum mechanics to perform parameter estimation and improve the measurement precision by quantum effects. With the experimental developments of ultracold atoms, ultracold atomic ensemble provides an excellent platform for implementing quantum metrology. Attributed to well-developed techniques of quantum control, one can prepare several exotic non-Gaussian multi-particle entangled states in the ensembles of ultracold atoms. Based on many-body quanum interferometry, and using these non-Gaussian entangled states as probe, the high-precision measurement beyond the standard quantum limit can be realized. This article introduces the background and advancement of this field.

Proteases constitute the largest enzyme family, yet their biological roles are obscured by our rudimentary understanding of their cellular substrates. There are 12 human caspases that play crucial roles in inflammation and cell differentiation and drive the terminal stages of cell death. Recent N-terminomics technologies have begun to enumerate the diverse substrates individual caspases can cleave in complex cell lysates. It is clear that many caspases have shared substrates; however, few data exist about the catalytic efficiencies (kcat/KM) of these substrates, which is critical to understanding their true substrate preferences. In this study, we use quantitative MS to determine the catalytic efficiencies for hundreds of natural protease substrates in cellular lysate for two understudied members: caspase-2 and caspase-6. Most substrates are new, and the cleavage rates vary up to 500-fold. We compare the cleavage rates for common substrates with those found for caspase-3, caspase-7, and caspase-8, involved in apoptosis. There is little correlation in catalytic efficiencies among the five caspases, suggesting each has a unique set of preferred substrates, and thus more specialized roles than previously understood. We synthesized peptide substrates on the basis of protein cleavage sites and found similar catalytic efficiencies between the protein and peptide substrates. These data suggest the rates of proteolysis are dominated more by local primary sequence, and less by the tertiary protein fold. Our studies highlight that global quantitative rate analysis for posttranslational modification enzymes in complex milieus for native substrates is critical to better define their functions and relative sequence of events.

Pulmonary hypertension is characterized by extensive vascular remodelling, leading to increased pulmonary vascular resistance and eventual death due to right heart failure. The pathogenesis of pulmonary hypertension involves vascular endothelial dysfunction and disordered vascular smooth muscle cell (VSMC) proliferation and migration, but the exact processes remain unknown. Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid involved in a wide spectrum of biological processes. S1P has been shown to regulate VSMC proliferation and migration and vascular tension via a family of five S1P G-protein-coupled receptors (S1P1-SIP5). S1P has been shown to have both a vasoconstrictive and vasodilating effect. The S1P receptors S1P1 and S1P3 promote, while S1P2 inhibits VSMC proliferation and migration in vitro in response to S1P. Moreover, it has been reported recently that sphingosine kinase 1 and S1P2 inhibitors might be useful therapeutic agents in the treatment of empirical pulmonary hypertension. The sphingosine kinase 1/S1P signalling pathways may play a role in the pathogenesis of pulmonary hypertension. Modulation of this pathway may offer novel therapeutic strategies.

Applications of single Flywheel Energy Storage System (FESS) to suppress power system multi-mode oscillations is presented in the paper. Based on independent active power and reactive power control loops and damping torque analysis, the feasibility of damping power system multi-mode oscillations using single FESS is studied. Based on modal analysis, the effective control loops are determined to install auxiliary damping controllers in FESS and the effective feedback signals to select to suppress each oscillation mode. And the eigenvalue analysis and non-linear simulation results show that single FESS has ability of damping power system multi-mode oscillations by an example of four-machine power system with FESS-based stabilizers.

Based on the design of SRRC roll-off filter used in DTTB system, a FPGA implementation method of using DA combined with the switch structure of multi-phase decomposition is proposed in this paper. The theoretical analysis and MATLAB simulation are adopted to verify the feasibility of the algorithm.