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Background Cancer patients are at a high risk of being infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), and are more likely to develop severe illness and have higher mortality once infected. In the COVID‐19 pandemic, it is urgent to understand the effects of antitumor therapy on the prognosis of patients with COVID‐19. Methods A systematic literature search was conducted in PubMed, Cochrane Library, Embase, MedRxiv, and Chinese National Knowledge Infrastructure (CNKI) until 21 June 2020. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were evaluated using a random effects model to analyze the effects of antitumor therapies on COVID‐19 patients. Results For cancer patients with COVID‐19, the death events related to antitumor treatment were higher than those with no antitumor treatment (OR = 1.55; 95% CI 1.07–2.25; p = 0.021). Compared with patients in the survival group, the non‐survival group showed no significant differences in patients who received antitumor therapy. Compared with patients in the non‐severe group, the severe group was more likely to receive antitumor therapy (OR = 1.50; 95% CI 1.02–2.19; p = 0.037) and there was a significant difference. The incidence of severe events was higher in the subgroup of chemotherapy (OR = 1.73; 95% CI 1.09–2.73). Conclusion The synthesized evidence suggests that cancer patients with COVID‐19 who received antitumor treatment shortly before symptom onset are more likely to experience severe symptoms and have high mortality. Receiving chemotherapy is an unfavorable factor for the prognosis of cancer patients with COVID‐19., Patients with cancer and COVID‐19 who received anti‐tumor treatment shortly before symptom onset are more likely to develop severe illness and have high a mortality. Receiving chemotherapy is an unfavorable factor for the prognosis of patients with COVID‐19.

Two methods based on local stress responses are proposed to locate fatigue critical point of metallic notched components under non-proportional loading. The points on the notch edge maintain a state of uniaxial stress even when the far-field fatigue loading is multi-axial. The point bearing the maximum stress amplitude is recognized as fatigue critical point under the\ud condition of non-mean stress, otherwise the Goodman’s empirical formula is adopted to amend mean stress effect prior to the determination of fatigue critical point. Furthermore, the uniaxial stress state can be treated as a special multi-axial stress state. The Susmel’s fatigue damage parameter is employed to evaluate the fatigue damage of these points on the notch edge.\ud Multi-axial fatigue tests on thin-walled round tube notched specimens made of GH4169 nickel-base alloy and 2297 aluminum-lithium alloy are carried out to verify the two methods. The prediction results show that both the stress amplitude method and the Susmel’s parameter method can accurately locate the fatigue critical point of metallic notched components under multi-axial fatigue loading.

A loosely coupled fluid-structural thermal numerical method is introduced for the thermal protection system (TPS) gap thermal control analysis in this paper. The aerodynamic heating and structural thermal are analyzed by computational fluid dynamics (CFD) and numerical heat transfer (NHT) methods respectively. An interpolation algorithm based on the control surface is adopted for the data exchanges on the coupled surface. In order to verify the analysis precision of the loosely coupled method, a circular tube example was analyzed, and the wall temperature agrees well with the test result. TPS gap thermal control performance was studied by the loosely coupled method successfully. The gap heat flux is mainly distributed in the small region at the top of the gap which is the high temperature region. Besides, TPS gap temperature and the power of the active cooling system (CCS) calculated by the traditional uncoupled method are higher than that calculated by the coupled method obviously. The reason is that the uncoupled method doesn't consider the coupled effect between the aerodynamic heating and structural thermal, however the coupled method considers it, so TPS gap thermal control performance can be analyzed more accurately by the coupled method.

The fatigue damage of composite sandwich panels is divided into two parts: the face sheet damage and the core damage. Both the two kinds of damage cause the performance degradation of panels, however only the core damage results in the ultimate failure. In this paper, a fatigue damage model of the face sheet and the core is proposed and three-point bending tests are carried out to obtain the deflection evolution curves. With the proposed model, the fatigue damage can be predicted accurately, which proves the validity of the fatigue damage model proposed in this paper.

In this paper, the bending fatigue tests of honeycomb sandwich panels are carried out by using an improved three-point bending test fixture, and the S-N curves at different stress ratios are obtained. Through the records of fatigue damage in the experiment, the failure mode of the honeycomb sandwich panels and the source of fatigue damage are determined. At the same time, through the calculation of the shear stress distribution on the honeycomb wall, the reasons for the difference in the failure morphology of the L-direction and W-direction sandwich panels are clarified. Besides, a life prediction method is proposed and its effectiveness in predicting the fatigue life of sandwich panels has been verified.

Astragalus polysaccharides (APS) have been shown to possess a variety of biological activities including anti-oxidant and anti-inflammation functions in a number of diseases. However, their function in pulmonary arterial hypertension (PAH) is still unknown. Rats received APS (200[Formula: see text]mg/kg once two days) for 2 weeks after being injected with monocrotaline (MCT; 60[Formula: see text]mg/kg). The pulmonary hemodynamic index, right ventricular hypertrophy, and lung morphological features of the rat models were examined, as well as the NO/eNOS ratio of wet lung and dry lung weight and MPO. A qRT-PCR and p-I[Formula: see text]B was used to assess IL-1[Formula: see text], IL-6 and TNF-[Formula: see text] and WB was used to detect the total I[Formula: see text]B. Based on these measurements, it was found that APS reversed the MCT-induced increase in mean pulmonary arterial pressure (mPAP) (from 32.731[Formula: see text]mmHg to 26.707[Formula: see text]mmHg), decreased pulmonary vascular resistance (PVR) (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text] min/L to 246.351[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L), and reduced right ventricular hypertrophy (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L to 246.351 mmHg[Formula: see text][Formula: see text][Formula: see text]min/L) ([Formula: see text]0.05). In terms of pulmonary artery remodeling, the WT% and WA% decreased with the addition of APS. In addition, it was found that APS promoted the synthesis of eNOS and the secretion of NO, promoting vasodilation and APS decreased the MCT-induced elevation of MPO, IL-1[Formula: see text], IL-6 and TNF-[Formula: see text], reducing inflammation. Furthermore, APS was able to inhibit the activation of pho-I[Formula: see text]B[Formula: see text]. In couclusion, APS ameliorates MCT-induced pulmonary artery hypertension by inhibiting pulmonary arterial remodeling partially via eNOS/NO and NF-[Formula: see text]B signaling pathways.

In order to solve the problem of 3D intricate product design and mold development, an approach based on UG NX was proposed. The design platform and modular technology of UG MoldWizard were introduced. How to add and edit attributes of the standard part library was explained by using sankyo lifter as example. As an application, a lamp set and its injection mold were rapidly designed by UG MoldWizard. How to patch surfaces, define parting lines and how to extract mold core and mold cavity were illustrated step by step. It proved that UG MoldWizard efficiently promoted work and integrated complex elements of design technology into automated sequences.