Study on the effect of new type liquid accelerator on the performance of shotcrete

Shotcrete is an essential preliminary support means in New Austrian Tunneling Method (NATM) construction and plays a very important role in controlling the stability of surrounding rock. The accelerator is a necessary admixture in shotcrete and its quality can greatly affect shotcrete performance. This paper proposes a new liquid accelerator characterized by short initial and final setting time, small dosage, and good adaptability to cement. Laboratory tests and field tests are conducted to verify the influence of this liquid accelerator on performance of shotcrete. Numerical simulation is carried out to study the strength growth of shotcrete with time and interaction between the strength and stress release of surrounding rock. The results show that the initial and final setting time of this liquid accelerator is 2 minutes and 4 minutes respectively. Its dosage is just 1.5% to 4% of the cement quantity. Adding this liquid accelerator can effectively improve the early strength and reduce the later strength loss of shotcrete, and therefore enhance the supporting effects of shotcrete on surrounding rock. In the field application, it is an ideal liquid accelerator for shotcrete, characterized by little resilience, no slurry shedding, and low dust

Prognostic value of inflammatory nutritional scores in locally advanced esophageal squamous cell carcinoma patients undergoing neoadjuvant chemoimmunotherapy: a multicenter study in China

ObjectiveThis study investigates the prognostic significance of inflammatory nutritional scores in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC) undergoing neoadjuvant chemoimmunotherapy.MethodsA total of 190 LA-ESCC patients were recruited from three medical centers across China. Pre-treatment laboratory tests were utilized to calculate inflammatory nutritional scores. LASSO regression and multivariate logistic regression analyses were conducted to pinpoint predictors of pathological response. Kaplan-Meier and Cox regression analyses were employed to assess disease-free survival (DFS) prognostic factors.ResultsThe cohort comprised 154 males (81.05%) and 36 females (18.95%), with a median age of 61.4 years. Pathological complete response (pCR) was achieved in 17.38% of patients, while 44.78% attained major pathological response (MPR). LASSO and multivariate logistic regression analyses identified that hemoglobin, albumin, lymphocyte, and platelet (HALP) (P=0.02) as an independent predictors of MPR in LA-ESCC patients receiving neoadjuvant chemoimmunotherapy. Kaplan-Meier and log-rank tests indicated that patients with low HALP, MPR, ypT1-2, ypN0 and, ypTNM I stages had prolonged DFS (P < 0.05). Furthermore, univariate and multivariate Cox regression analyses underscored HALP (P = 0.019) and ypT (P = 0.029) as independent predictive factors for DFS in ESCC.ConclusionOur study suggests that LA-ESCC patients with lower pre-treatment HALP scores exhibit improved pathological response and reduced recurrence rate. As a comprehensive index of inflammatory nutritional status, pre-treatment HALP may be a reliable prognostic marker in ESCC patients undergoing neoadjuvant chemoimmunotherapy

Smad7 enables STAT3 activation and promotes pluripotency independent of TGF-β signaling

TGF-β and related growth factors critically regulate cell potency and functions. Smad7 is induced by TGF-βs and inhibits the physiological functions of TGF-β signaling. This study describes an unexpected finding that Smad7 promotes self-renewal of embryonic stem cells (ESCs) in a manner independent of its inhibition on TGF-β signaling. Instead, Smad7 acts to induce activation of transcription factor signal transducers and activators of transcription 3 (STAT3) in ESCs. Smad7 activates STAT3 through its direct binding to the cytokine receptor upstream of STAT3 activation. In agreement with the role of STAT3 in maintaining ESC pluripotency, Smad7 promotes ESC self-renewal and induced pluripotent stem cell reprogramming. This finding illustrates a regulatory mechanism for Smad7 in maintaining pluripotency, and likely in cancer and inflammation

Roadmap on commercialization of metal halide perovskite photovoltaics

Perovskite solar cells (PSCs) represent one of the most promising emerging photovoltaic technologies due to their high power conversion efficiency. However, despite the huge progress made not only in terms of the efficiency achieved, but also fundamental understanding of the relevant physics of the devices and issues which affect their efficiency and stability, there are still unresolved problems and obstacles on the path toward commercialization of this promising technology. In this roadmap, we aim to provide a concise and up to date summary of outstanding issues and challenges, and the progress made toward addressing these issues. While the format of this article is not meant to be a comprehensive review of the topic, it provides a collection of the viewpoints of the experts in the field, which covers a broad range of topics related to PSC commercialization, including those relevant for manufacturing (scaling up, different types of devices), operation and stability (various factors), and environmental issues (in particular the use of lead). We hope that the article will provide a useful resource for researchers in the field and that it will facilitate discussions and move forward toward addressing the outstanding challenges in this fast-developing field

Edge states in a two-dimensional honeycomb lattice of massive magnetic skyrmions

We study the collective dynamics of a two-dimensional honeycomb lattice of magnetic skyrmions. By performing large-scale micromagnetic simulations, we find multiple chiral and non-chiral edge modes of skyrmion oscillations in the lattice. The non-chiral edge states are due to the Tamm-Shockley mechanism, while the chiral ones are topologically protected against structure defects and hold different handednesses depending on the mode frequency. To interpret the emerging multiband nature of the chiral edge states, we generalize the massless Thiele's equation by including a second-order inertial term of skyrmion mass as well as a third-order non-Newtonian gyroscopic term, which allows us to model the band structure of skrymion oscillations. Theoretical results compare well with numerical simulations. Our findings uncover the importance of high order effects in strongly coupled skyrmions and are helpful for designing novel topological devices.Comment: 6 pages,4 figures,accepted by Physical Review B as a Rapid Communicatio

Research Progress in Rat Models of Intrauterine Adhesion

Intact endometrium and proper endometrial thickness are the necessary conditions for normal uterine reproductive function. Intrauterine adhesion (IUA) can cause recurrent abortion and infertility, which seriously affects the normal reproductive function of patients. At present, the treatment methods for IUA include surgery elimination and use of estrogen, but there are problems such as poor effectiveness, high rate of recurrence, and still with low pregnancy rate. The specific pathogenesis and developmental mechanism of IUA and the repair mechanism of damaged endometrium are still unclear. Establishing an appropriate animal model is conducive to the research of human IUA in all aspects. Here, we introduced the common rat models of IUA in recent years, including physical and mechanical damage method, chemical damage method, biological damage method and combined damage method, and described its application from the aspects of modeling rate, stability, and pathogenesis of IUA, and discussed the observation indexes to evaluate the success of modeling, in order to provide useful reference for selecting appropriate modeling methods. Generally, the combined model of repeated endometrial damage and infection of pregnant rats may be more suitable for the clinical IUA caused by multiple abortions and infections after curettage

Knockdown of ubiquitin-specific peptidase 39 inhibited the growth of osteosarcoma cells and induced apoptosis in vitro

Abstract Background Ubiquitin specific peptidase 39 (USP39), an essential factor in the assembly of the mature spliceosome complex, has an aberrant expression in several cancer. However, its function and the corresponding mechanism on human osteosarcoma has not been fully explored yet. Methods The mRNA and DNA copies of USP39 were increased in osteosarcoma cancer tissues compared with the one in human normal tissues according to datasets from the publicly available Oncomine database. A further western blot analysis also demonstrated an aberrant endogenous expression of USP39 in three different osteosarcoma cells. Then lentivirus-mediated short hairpin RNA (shRNA) was designed to silence USP39 in human osteosarcoma cell line U2OS, which is used to test the impact of USP39-silencing on cellular proliferation, colony formation, cell cycle distribution and apoptosis. Results Knockdown of USP39 expression in U2OS cell significantly decreased cell proliferation, impaired colony formation ability. A further analysis indicated suppression of USP39 arrested cell cycle progression at G2/M phase via p21 dependent way. In addition, the results of Annexin V/7-AAD staining suggested the knockdown of USP39 could promote U2OS cell apoptosis through PARP cleavage. Conclusions These results uncover the critical role of USP39 in regulating cancer cell mitosis and indicate USP39 is critical for osteosarcoma tumorigenesis