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BACKGROUND: Primary sclerosing cholangitis (PSC) is an immune-mediated, chronic cholestatic liver disease. Currently, liver transplantation is the only established life-saving treatment. Several studies have evaluated the effect of different biologic therapies on PSC with inconclusive findings. We conducted a systematic review and meta-analysis to assess the effects of biologics in PSC and associated inflammatory bowel disease (IBD). METHODS: MEDLINE, Scopus, and Embase were searched up to July 31, 2023, for studies reporting the effects of biologics in patients with PSC-IBD. Effects of biologic therapy on alkaline phosphatase, total bilirubin, ulcerative colitis response score, and adverse events were calculated and expressed as standardized difference of means (SMD), proportions, and 95% CI using a random-effects model. RESULTS: Six studies, including 411 PSC-IBD patients who received biologics, were included. Biologic treatment was associated with no change in alkaline phosphatase (SMD: 0.1, 95% CI: -0.07 -0.17, p=0.43), but a small and statistically significant increase in total bilirubin (SMD: 0.2, 95% CI: 0.05-0.35, p

[Objective] The resilience of urban network structures is a crucial guarantee for the recovery and stability of urban spatial organization. Current research predominantly employs individual flows and focuses on developed regions, and there is relatively little research that combines multidimensional factor flows while also focusing on the resilience of network structures in underdeveloped regions. Therefore, this study took the underdeveloped Northwest China as the research object and explored its network structural resilience based on multidimensional factor flow, in order to fill the gap of related research and enrich the empirical analysis of network resilience from the perspective of multidimensional factor flow. [Methods] This study focused on 51 prefecture-level administrative units in Northwest China for the year 2022. It investigated the structural characteristics of urban networks from three perspectives: economic, transportation, and information, quantitatively measured their hierarchy, matching, transmission, and agglomeration, and examined the structural resilience of Northwest China’s urban networks under various disruption scenarios by using the method of computer simulation and proposed optimization strategies from different perspectives. [Results] (1) The economic, transportation, and information networks across the 51 prefecture-level administrative units in Northwest China are generally distributed in a pattern of dense in the east and sparse in the west, showing core-periphery characteristics, but there are significant differences in the structure of the three types of networks. The economic network density is low and the stickiness between the core nodes is large, showing the characteristics of coexistence of “strong assisting weak” and “strong alliances”, with multi-group pattern and fragmented development trend. The traffic network is more closely linked, with stronger inertia in intercity links, showing a “small world” effect, a spindle-shaped pattern, and a turbulent development trend. The information network has wide coverage and strong permeability, showing coordinated characteristics, a strip-like pattern, and a turbulent development trend. (2) The three types of networks differ greatly in terms of hierarchy and matching, and less in terms of transmission and agglomeration. The Matthew effect of the economic network is obvious, characterized by strong homophily at the core and weak heterophily at the periphery; the traffic network tends to experience three-dimensional development, showing local robustness and regional vulnerability; and the information network has highly heterogeneous resilience, showing the characteristics of flattened network structure and diversified connection paths, with a high level of resilience. (3) Deliberate attacks are significantly more damaging to network resilience than random attacks, and a hit on a core node has a greater impact on network operational efficiency than on a vulnerable node. [Conclusion] The problem of uneven regional development is particularly obvious in less developed regions, where the core city has concentrated power but a shorter radius of radiation, and cities on the periphery are not sufficiently motivated to develop. There are both similarities and differences in resilience characteristics between the three types of networks, and network resilience under different attack modes is characterized by phased changes. In order to promote the sustainable development of the region, response policies should be formulated according to regional characteristics.

Coupling model for two-dimensional mixed-compression supersonic inlet with Mach number of 2.5 at design point and pulse detonation combustor was established, and three working schemes were designed to investigate multi cycle working process by using unsteady numerical simulation with chemical reaction. The results show that the following two measurements can both restrain the back-propagating compression wave and broaden the stability margin of the inlet and increase the frequency, one of which is the pressure relief at the outlet of the combustor, the other is valve at the inlet of the combustor. Nevertheless, the former will lose thrust, while the latter can greatly increase thrust. Meanwhile, the valve will reflect the compression wave in the production; increase the turbulence in the combustor, and make the gas entrained into the diffuser section of the inlet at the moment of opening the valve. However, the reflected compression wave in the hot production will not affect the velocity and shape of the detonation wave. Furthermore, in the period of detonation wave initiation and propagation, the blockage ratio of physical obstructions at the inlet of the combustor should be expanded as much as possible. At the same time, the flow at the outlet of the inlet should not be blocked to increase the flow resistance.