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Lithium niobate Mach–Zehnder modulators (MZMs) with compact footprint and fast electro-optics (EO) responses are highly demanded for the next-generation optical interconnect systems. Here, we demonstrate slow-light (SL) effect using a coupled Bragg resonator structure on the thin-film lithium niobate (TFLN) platform, and an ultra-compact SL-MZM with length L of ∼370 μm is also constructed. The fabricated SL waveguides show a large optical passband width of ∼8 nm, an insertion loss of 2.9 dB, and a maximal optical group index of 7.50, corresponding to 3.4 times as large as that of regular TFLN rib waveguide. The fabricated SL-MZM exhibits a large EO bandwidth of >50 GHz in an operating wavelength band of ∼8 nm as well. High-speed OOK transmissions at data rates of 64 Gbit/s and 80 Gbit/s are successfully achieved. To our best knowledge, it is first time to build SL waveguides and compact SL-MZMs with large EO bandwidths of >50 GHz on the monolithic TFLN platform.

Background Stroke is one of the major public health problems affecting human health in current. Longitudinal check up data has accumulated a large amount of health information. However, the utilization rate of the longitudinal check up data is low and important information has not been fully extracted due to many problems such as missing data and small sample size, which brings difficulties to the effective prevention and control of common chronic diseases. Objective To explore the risk factors of stroke in check-up population based on Bayesian multivariate joint model, so as to provide a new approach for the analysis of risk factors for chronic diseases. Methods In this study, the data were collected from the Center for Health and Medicine, Xijing Hospital, Air Force Military Medical University from 2008 to 2015. Follow-up status: the follow up was conducted with the first occurrence of stroke as the outcome event and stopped at the occurrence of outcome event or ended when the collection of medical examination information was completed by 2015 if the outcome event did not occur. The interval between physical examinations was 1 year. The participants were divided into the stroke group and the non-stroke group according to whether stroke occurred during follow-up. Longitudinal variables observed in this study included total cholesterol (TC) , triglyceride (TG) , low density lipoprotein cholesterol (LDL-C) , high density lipoprotein cholesterol (HDL-C) , body mass index (BMI) and systolic blood pressure (SBP) . Multivariate Cox regression model was used to analyze the influence of baseline conditions on stroke outcome events. Bayesian multivariate joint model was used for analyzing the effect of longitudinal trajectory of TC, TG, LDL-C, HDL-C, BMI and SBP on the incidence of stroke during follow-up. Results A total of 234 subjects with 1 581 longitudinal follow-up records were included in this study, with the mean follow-up time of (7.4±1.2) years, of which 70 cases (29.9%) developed stroke during the follow-up. The results of multivariate Cox proportional hazards model showed that there was no effect of baseline values including TC, TG, LDL-C, HDL-C, BMI and SBP on the incidence of stroke (P>0.05) . The results of Bayesian multivariate joint model showed that the risk of stroke was 1.863 times higher for per longitudinal increase of 1 mmol/L TG level 〔95%CI (1.018, 3.294) , P=0.042〕 and 1.347 times higher for per longitudinal increase of 1 mmol/L LDL-C level〔95%CI (1.045, 1.863) , P=0.046〕. Conclusion The longitudinal increase of TG and LDL-C levels over time is a risk factor for stroke in check-up population. Bayesian multivariate joint model can be used to explore the risk factors of chronic diseases in check-up population.

In many regions across the world, hepatitis B virus (HBV) infection is still endemic and the transmission rate is much greater than majority of the known epidemic diseases. Numerous mathematical models (utilizing various differential operators) have been put forth over the past 20 years to understand the transmission mechanism of HBV in various nations and geographical areas. In this manuscript, an epidemic model with various novelties for capturing the dynamic of HBV while utilizing Caputo–Fabrizio fractional differential operator with asymptomatic carriers and vaccination effects is introduced. Initially, the model is formulated by using the ordinary derivative, and afterward, the fractional differential operator is applied to transform the model into arbitrary-ordered derivative. A few basic mathematical properties for the proposed integer-ordered model is presented. The existence of solution to the problem and its uniqueness of the fractional order model are established by transforming the problem into integral equations and then applying the standard results of fixed point theory. For boundedness and positivity of model’ solution is elaborated utilizing the techniques of fractional calculus. It is too much important to validate the theoretical findings through simulations; therefore, the solution curves of the model under consideration are displayed by using the well-known approach called the Mittag-Leffler. To show the behavior of the order of the operator on the dynamics of the disease, various graphical illustrations are presented at the end of the manuscript. By comparing the findings of the present study with the available literature, it is observed that fractional derivative is better to use than integer-order operator for capturing the realistic scenario of the disease.

Osteoblasts originate from mesenchymal stem cells (MSCs) and their maturation is regulated by numerous genes. However, specific genes that play decisive roles in osteoblast maturation are not completely understood. Herein, we propose a new algorithm called SGCAL to identify sensitive gene combinations during osteoblast development and decode the regulatory roles of sensitive gene combinations in cell development. In contrast to conventional gene identification algorithms, the SGCAL algorithm, which is based on a combination of ARNN-LNE iterative cycles, quantitatively evaluates the sensitivity of genes by analyzing the average network entropy before and after gene perturbation. We verified that osteoblast development is fundamentally regulated by an overall sensitive network formed by specific genes. Moreover, we explored the roles of these sensitive genes and their combinations in the transition time point of the initial state of network change. Our algorithm was validated on two independent mouse osteoblast development datasets, successfully identifying sensitive genes and their combinations in both datasets and revealing that gene combinations containing Col1a1 can exhibit significant sensitivity. This study demonstrated the universality of cell fate and network regulation, offering new insights and a theoretical basis for the treatment and repair of bone diseases An algorithm called SGCAL is proposed to check effectively the sensitive genes and their combination during osteoblast development. The gene combinations containing Col1a1 can exhibit significant sensitivity for the process of Osteoblasts. We perturb expression data to discern the sensitivity of the maker gene by measuring the network entropy. [ABSTRACT FROM AUTHOR]

The formation of spatial patterns is an important issue in reaction–diffusion systems. Previous studies have mainly focused on the spatial patterns in reaction–diffusion models equipped with symmetric diffusion (such as normal or fractional Laplace diffusion), namely, assuming that spatial environments of the systems are homogeneous. However, the complexity and heterogeneity of spatial environments of biochemical reactions in vivo can lead to asymmetric diffusion of reactants. Naturally, there arises an open question of how the asymmetric diffusion affects dynamical behaviors of biochemical reaction systems. To answer this, we build a general asymmetric Lévy diffusion model based on the theory of a continuous time random walk. In addition, we investigate the two-species Brusselator model with asymmetric Lévy diffusion, and obtain a general condition for the formation of Turing and wave patterns. More interestingly, we find that even though the Brusselator model with symmetric diffusion cannot produce steady spatial patterns for some parameters, the asymmetry of Lévy diffusion for this model can produce wave patterns. This is different from the previous result that wave instability requires at least a three-species model. In addition, the asymmetry of Lévy diffusion can significantly affect the amplitude and frequency of the spatial patterns. Our results enrich our knowledge of the mechanisms of pattern formation. [ABSTRACT FROM AUTHOR]

Background: In locally advanced rectal cancer (LARC), optimizing neoadjuvant strategies, including the addition of concurrent chemotherapy and dose escalation of radiotherapy, is essential to improve tumor regression and subsequent implementation of anal preservation strategies. Currently, dose escalation studies in rectal cancer have focused on the primary lesions. However, a common source of recurrence in LARC is the metastasis of cancer cells to the proximal lymph nodes. In our trial, we implement simultaneous integrated boost (SIB) to both primary lesions and positive lymph nodes in the experimental group based on magnetic resonance-guided adaptive radiotherapy (MRgART), which allows for more precise (and consequently intense) targeting while sparing neighboring healthy tissue. The objective of this study is to evaluate the efficacy and safety of MRgART dose escalation to both primary lesions and positive lymph nodes, in comparison with the conventional radiotherapy of long-course concurrent chemoradiotherapy (LCCRT) group, in the neoadjuvant treatment of LARC. Methods: This is a multi-center, randomized, controlled phase III trial (NCT06246344). 128 patients with LARC (cT3-4/N+) will be enrolled. During LCCRT, patients will be randomized to receive either MRgART with SIB (60–65 Gy in 25–28 fractions to primary lesions and positive lymph nodes; 50–50.4 Gy in 25–28 fractions to the pelvis) or intensity-modulated radiotherapy (50–50.4 Gy in 25–28 fractions). Both groups will receive concurrent chemotherapy with capecitabine and consolidation chemotherapy of either two cycles of CAPEOX or three cycles of FOLFOX between radiotherapy and surgery. The primary endpoints are pathological complete response (pCR) rate and surgical difficulty, while the secondary endpoints are clinical complete response (cCR) rate, 3-year and 5-year disease-free survival (DFS) and overall survival (OS) rates, acute and late toxicity and quality of life. Discussion: Since dose escalation of both primary lesions and positive nodes in LARC is rare, we propose conducting a phase III trial to evaluate the efficacy and safety of SIB for both primary lesions and positive nodes in LARC based on MRgART. Trial registration: The study was registered at ClinicalTrials.gov with the Identifier: NCT06246344 (Registered 7th Feb 2024). [ABSTRACT FROM AUTHOR]

【Background】 In order to alleviate the shortage of water resources, China has established many water transfer projects. Due to its long water transfer distance, large water delivery volume, and numerous water passing buildings along the line, the control process is very complicated. Unsteady flow will inevitably appear in the channel operation scheduling process, and the Saint-Venant equations are an important way to describe and solve the unsteady flow. 【Objective】 With the construction of large-scale water transfer projects and the complexity of the operation scheduling and control process, the traditional method of solving the sparse matrix of the original Saint-Venant equations has been unable to meet the requirements of calculation volume and calculation speed. In order to find efficient and stable algorithms for solving large and sparse linear equations to improve the speed of solving Saint-Venant equations. 【Method】 In this paper, four algorithms for solving Saint-Venant equations based on the four-point eccentric scheme are summarized and improved, and the calculation efficiency of different algorithms is compared through simulation experiments. 【Result】 From the simulation results, it can be seen that when the number of calculation sections is small (less than 500), the calculation time of all methods is basically the same; when the number of calculation sections is large (more than 500), the speed of the four algorithms is improved compared with the traditional algorithm.When the number of cross sections is 1520, the calculation speed of the four algorithms is 4 times that of the traditional algorithm. When the number of cross sections is 3040, the calculation speed is more than 10 times. 【Conclusion】 The improved GE and PM algorithms have faster calculation speed and higher calculation efficiency when the number of cross sections is larger. The results of this paper have reference value for improving the calculation speed of large channel non-constant flow simulation. The method can be applied to canal system automatic control technology such as MPC control, LQR control point, etc., to improve the running speed of simulation program.

Considering the time delay originating from a certain incubation period or asymptomatic state, we propose a delayed epidemic system within the noisy environment of the hepatitis B virus to analyze the mechanism of disease transmission and elucidate how to control it by applying the strategy of vaccinating and treatment. Applying stochastic Lyapunov functional theory, we first construct an integral Lyapunov function coupling the time delay and stochastic fluctuation to investigate whether there exists a unique global solution to the model. Next, we yield the threshold condition for controlling disease extinction, and persistence, as well as its stationary distribution. Governed by these sufficient conditions, we study the existence of optimal control solutions in deterministic and stochastic scenarios to uncover how to accelerate disease extinction through vaccination and treatment. The results indicate that the time delay will prolong the duration of the disease for the original system but suppress the peak value of HBV in the controlled system. Finally, we verify the versatility of theoretical results by numerical simulations. These results will effectively decipher the importance of the time delay in the control of hepatitis B. [ABSTRACT FROM AUTHOR]

As ferroelectric materials, lithium tantalate and lithium niobate share similar material characteristics, such as a high Pockels effect and nonlinear optical coefficients. When compared to lithium niobate, lithium tantalate offers a higher optical damage threshold, a broader transparent window, and lower birefringence, making it a promising candidate for high-performance electro-optical photonic integrated devices. In this study, we design and successfully fabricate micro-ring resonators on an acoustic-grade lithium-tantalate-on-insulator wafer, demonstrating their tunability and dynamic modulation capabilities. Experimental results indicate that the achieved thin-film lithium tantalate based micro-ring resonator exhibits an intrinsic Q-factor of 8.4 × 105, corresponding to a waveguide propagation loss of 0.47 dB/cm and a tuning efficiency of 1.94 pm/V. More importantly, as compared to those based on thin-film lithium niobate, a much weaker photorefractive effect and drift phenomenon around the 1550 nm wavelength under a direct-current drive are observed in the present fabricated thin-film lithium tantalate micro-rings with a silicon oxide over-cladding and a tuning electrode on top. [ABSTRACT FROM AUTHOR]