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The shortages of river sand and freshwater in marine engineering can be addressed by utilizing seawater and sea sand concrete (SWSSC). However, the sulfate resistance of SWSSC at low temperature is not clear. In this study, the seawater and sea sand cement mortar (SSCM) and ordinary cement mortar (OCM) with different limestone powder (LP) content were corroded by different sulfate solutions at 5 °C. The change of compressive strength and compositions of corrosion products in mortars after different times of corrosion were studied. The results show that SSCM presents 9.4∼19 % lower strength loss and better sulfate resistance than OCM. The presence of Friedel's salt in SSCM contributes to a reduction in corrosion products like ettringite, gypsum, and thaumasite, thereby minimizing microstructural damage and mitigating the thaumasite sulfate attack (TSA). All mortars containing LP suffer from TSA and significantly damage with 17.4∼48.7 % strength loss after 360 days of MgSO 4 or Na 2 SO 4 corrosion. Increasing the LP content exacerbates the TSA damage in SSCM. This is primarily due to the additional soluble carbonate from LP promoting the formation of gypsum and thaumasite, thereby worsening the microstructure deterioration of SSCM. Meanwhile, the thaumasite is not found in SSCM without LP after corrosion. In contrast to Na 2 SO 4 corrosion, the thaumasite formation under MgSO4 corrosion mainly results from indirect reaction. The combined corrosion effects of Mg2+ and SO 4 2- lead to a more significant increase in expansive products (thaumasite and gypsum) and TSA damage. The findings of this study help to advance the sulfate resistance of SWSSC in marine environments. • The TSA characteristics of seawater sea sand cement concrete under sulfate attack at 5 °C were summarized. • The sulfate resistance of seawater sea sand cement mortar and ordinary cement mortar were compared. • The effect of LP content on the TSA characteristics of seawater sea sand cement mortar was evaluated. • The differences of sodium sulfate and magnesium sulfate during the TSA damage were discussed. [ABSTRACT FROM AUTHOR]

As the development of neuromorphic computing, it is meaningful to explore the synaptic memristors based on organic materials owing to their advantages in low cost, good mechanical flexibility and strong biocompatibility. In this work, organic pentacene thin films have been deposited on different substrates by the thermal evaporation method. The prepared thin films on SiO 2 /Si substrates demonstrate the co-existence of digital and analog resistive switching (RS) behaviors as well as a series of synaptic plasticity. To characterize the flexibility of the organic thin films, lateral memristors have been fabricated on polyethylene terephthalate (PET) substrates and demonstrate comparable RS behaviors when the bending radius is decreased to 1.26 cm or after 1000 bending. Furthermore, vertical memristors with Pt/pentacene/indium tin oxide (ITO) structure have been constructed when the organic thin films are deposited on ITO/PET substrates, exhibiting bipolar RS behaviors with low SET voltage of 0.65 V. The vertical synaptic memristors can be used to simulate the "learning-forgetting" experience of human brain. More importantly, an artificial neural network (ANN) can be simulated based on the vertical synaptic memristors, demonstrating 93.8 % recognition accuracy for hand-written digit image. This study suggests potential applications of the organic pentacene thin films for neuromorphic computing. [Display omitted] • The pentacene thin films show the co-existence of digital and analog memristive behaviors. • The thin films on flexible substrates demonstrate good mechanical flexibility. • The vertical synaptic memristors can successfully simulate the "learning-forgetting" experience. • An artificial neural network based on the vertical memristors can be emulated with high image recognition accuracy. [ABSTRACT FROM AUTHOR]

Upright positions, as a non-pharmacological, have been well documented in multiple studies to promote normal labor, facilitate favourable birth outcomes and positive childbirth experience. Yet, the application status of upright positions in China, and even globally, is unfavourable. Thus, we have developed the Program for Upright Positions in the Second Stage of Labor (UPSSL program) for the widespread application of upright positions. While there is limited research evidence on the areas of improvement and corresponding strategies for embedding the evidence into midwifery practice. To explore perspectives of health care providers on improvement areas of upright positions in the second stage of labor, and to identify corresponding strategies in order to develop a management framework for successful implementation of upright positions. A qualitative descriptive design with semi-structured interviews was conducted in the study. The participants involving 13 midwives, six obstetricians and six department managers were selected from three hospitals in Beijing, China. ATLAS.TI 8 software was utilized to manage, identify the transcript data, and the thematic analysis method guided the data analysis. A management framework of upright positions in the second stage of labor was developed based on our study, which included five improvement areas : (1) promoting the renewal of midwifery notions and the professional training;(2) strengthening maternal health education based on the "trinity" approach; (3) promoting multidisciplinary cooperation and refining the labor procedures in upright positions; (4) optimizing midwifery human resource allocation and formulating incentive policies; (5) encouraging partner involvement and improving the birth environment. The study findings could provide a comprehensive view to promote UPSSL Program to be utilized in practice. Our study also provided a way for midwives, obstetricians, and other healthcare providers to work together to facilitate high quality maternal care. Our findings will be useful for nursing managers to carry out the UPSSL program through several strategies, such as strengthening the professional training for assisting labor in the upright positions, reallocating midwifery human resources, and developing the childbirth education on the upright positions. [ABSTRACT FROM AUTHOR]

Upright positions in the second stage of labour are recommended by many international organizations. However, they have not been widely used worldwide, especially in China. One of the important factors is the absence of a practice programme based on the best available evidence. We thus developed a Practice Programme for Upright Positions in the Second Stage of Labour following the UK Medical Research Council framework. Under the guidance of the programme, whether the use of upright positions can improve the maternal birth experience is a question of great concern. This study aimed to explore the birth experience of Chinese women who adopted upright positions in the second stage of labour. This qualitative descriptive study was conducted as part of an implementation study that developed an evidence-based intervention and used strategies to integrate the evidence-based intervention into routine obstetric clinical practice. The maternity department of a tertiary comprehensive hospital in Hebei Province, China. Semi-structured interviews with twelve eligible women who adopted upright positions in the second stage of labour were conducted between March and April 2022. Qualitative data were analyzed by using conventional content analysis. The average age of included women was 26.5 ± 3.5 years, and ten of them were primiparous women. Eight women adopted epidural analgesia during labour to relieve labour pain. All women gave birth in at least one type of upright position in the passive second stage of labour and adopted the semi-recumbent position in the active second stage of labour. Through conventional content analysis, we found that the use of upright positions in the second stage of labour could possibly promote an overall positive birth experience. Women giving birth in upright positions generally perceived they were more involved in their birthing process, and had greater physical and mental capacity to cope with childbirth. Women have a positive birth experience when using upright positions in the second stage of labour. This study suggests upright positions could improve women's birth experience and have the potential to be widely applied in clinical practice. [ABSTRACT FROM AUTHOR]

Highlights • The physical and chemical effects of limestone powder (LP) were calculated. • The chemical effect of LP was influenced by its particle size and amount of LP at 3d. • The particle size and amount of LP had little effect on its chemical effect at 180d. Abstract The study aims to quantitatively calculate the physical and chemical effects of limestone powder (LP) with four average particle sizes and two amounts in cement pastes by using thermal gravimetric analysis (TGA), X-ray diffraction (XRD), mercury intrusion porosimetry (MIP) techniques. At 3d, as the average particle size of LP decreased from 32 to 6 μm, the consumed CaCO 3 content in LP increased from 0.67% to 1.71%, and the chemically reactive portion of LP increased from 1.15% to 2.95%. However, at 180d, the consumed CaCO 3 content and chemically reactive portion of LP was almost 2.4% and 4.2%, respectively. At 3d, as the LP content increased from 25% to 50%, the consumed CaCO 3 content in LP increased from 1.71% to 2.02%, and the chemically reactive portion of LP increased from 2.95% to 3.5%. However, at 180d, the differences of consumed CaCO 3 content and chemically reactive portion of LP between cement pastes with different LP content were limited. The physical and chemical effects of limestone powder on the compressive strength of cement pastes were calculated. At 180d, as the average particle size of LP decreased from 32 to 6 μm, the contribution of chemical effect of LP on the compressive strength of cement pastes increased from 1.01% to 1.08% while the contribution of physical effect decreased from 21.19% to 20.03%. [ABSTRACT FROM AUTHOR]

Highlights • The effects of limestone powder (LS) depends on its particle size and content. • Using LS to replace fine aggregate improves the properties of concrete. • Using LS to replace cement reduces the properties of the concrete. Abstract Limestone powder (LS) is one of the mineral materials in concrete due to its wide availability and low cost. This paper discusses effects of LS on the workability, setting time, shrinkage, mechanical properties and durability of concrete. Such effects are mainly influenced by many factors, including the particle size and content of LS, the polymorph of calcium carbonate and synergetic effect between LS and alumina-rich supplementary cementitious materials (SCMs). In general, incorporating LS, as cement paste replacement or in the form of fine aggregate, improves the properties of concrete. Whereas, when LS is incorporated into concrete to replace cement, effects of LS on the properties of concrete depend on its particle size and content. In the end, some further research needs are also suggested. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy and safety of transarterial embolization (TAE) with n -butyl cyanoacrylate (n BCA) for juvenile nasopharyngeal angiofibroma (JNA). A retrospective review was performed on patients with JNA who underwent TAE and endoscopic resection between 2020 and 2022. Patients embolized with n BCA were identified, and those embolized with microspheres were set as the control group. Data on demographics, symptoms, tumor characteristics, blood loss, adverse events, residual disease, and recurrence were collected, and case-control analysis was performed for the 2 groups. Differences in characteristics between the groups were tested using the Fisher exact and Wilcoxon tests. A generalized linear model (GLM) was used to analyze the univariate and multivariate influences on blood loss. Twenty patients were included in this study: 13 in the microsphere group and 7 in the n BCA group. The median blood loss was 400 mL (interquartile range [IQR], 200–520 mL) in the n BCA group and 1,000 mL (IQR, 500–1,000 mL) in the microsphere group (P =.028). The GLM confirmed lower blood loss in the n BCA group (relative risk, 0.58 [0.41–0.83]; P =.01). A residual tumor was found in 1 patient in each group (7.7% vs 14.3%; P = 1.000). Recurrence was not observed in any patient. None of the patients experienced adverse events during embolization. TAE of advanced JNA with n BCA glue is safe and effective and can significantly reduce intraoperative blood loss compared with microspheres. [Display omitted] [ABSTRACT FROM AUTHOR]

The self-mixing technique based on the traditional reflecting mirror has been demonstrated with great merit for angle sensing applications. Here we demonstrate a modified self-reflection-mixing angle measurement system by combine a right-angle prism to self-mixing angle measurement. In our system, the wavelength is crucial to the angle measurement resolution. For a microchip solid-state laser, the measurement resolution can reach 0.49 mrad, while the resolution for the He-Ne laser is 0.53 mrad. In addition, the ranges in the system with the microchip solid-state laser and He-Ne laser are up to 22 mrad and 24.9 mrad respectively. This modified angle measurement system effectively combines the advantage of self-mixing measurement system with a compact structure, providing interesting features such as of high requisition of resolution and precision. [ABSTRACT FROM AUTHOR]

A sensitive and simple 2,6-diphenylpyridine-based receptor servered as a “turn-on” fluorescent chemosensor was designed and synthesized for selectively sensing Ag + ions in aqueous media with an anomalously quantum yield. The probe exhibits high selectivity toward Ag + over other common metal ions, displaying a significant fluorescent turn on nature in the presence of Ag + . The fluorescence response is explained by X-ray diffraction analysis, mass spectrometry, and theoretical calculations. The unprecedentedly high luminescence quantum yield can be attributed to intraligand charge transfer (ILCT) transitions with mixed some Ag(I) 5p orbitals perturbation characters. Finally, the results of cell experiments show that the probe can be used to selectively detect Ag + in mammalian cells. [ABSTRACT FROM AUTHOR]

This study investigated the flowability, compressive strength, heat of hydration, porosity and calcium hydroxide content of ultra-high-strength concrete (UHSC) with cement–silica fume–slag binder at 20 °C. The composition of the binder was designed using seven-batch factorial design method. The relationships between the binder composition and the properties were expressed in contours. Results showed that proper silica fume content could improve the flowability and compressive strength of UHSC, reduce the porosity and calcium hydroxide content of UHSC. Slag reduced the flowability, compressive strength, porosity, and calcium hydroxide content of UHSC to certain extent. The silica fume and slag demonstrated positive synergistic effects on the flowability and 3 d compressive strength, but have negative synergistic effects on the total heat of hydration, hydration heat when the time is infinitely long( P 0 ), 56 d compressive strength, porosity and calcium hydroxide content of UHSC. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider a discrete insurance risk model in which the claims, the premiums and the rates of interest are assumed to have dependent autoregressive structures (AR(1)). We derive recursive and integral equations for expected discounted penalty function. By these equations, we obtain generalized Lundberg inequality for the infinite time severity of ruin and hence for the infinite time ruin probability, consider asymptotic formula for the finite time ruin probability when loss distributions have regularly varying tails, and study some probability properties of the duration of ruin. [Copyright &y& Elsevier]

Carbonic anhydrase 9 (CA9), as a member of the carbonic anhydrase enzyme family, was an endogenous marker of hypoxia. Previous studies suggested CA9 expression was correlated with poor prognosis in multiple types of malignancies. Therefore, this study was to evaluate the role of CA9 in sinonasal squamous cell carcinoma (SNSCC) and to determine whether this biomarker was associated with patient clinicopathologic characteristics and prognosis. We assessed 63 patients diagnosed with SNSCC in 2013–2017 who underwent curative surgery. Tumor specimens was immunohistochemically analyzed for CA9 expression. The expression levels of CA9 was evaluated in relation to clinicopathological factors and prognosis. Positive expression of CA9 was observed in 21 (33.3%) patients and was significantly correlated with local recurrence (p = 0.016), overall survival (OS) (p = 0.003) and disease-free survival (DFS) (p = 0.002). In Cox's multivariate analysis, CA9 expression was an independent negative prognostic factor for OS (p = 0.048) and DFS (p = 0.019). Our findings demonstrated that CA9 overexpression could be used as an independent prognostic biomarker and therapeutic target in SNSCC. • This is the first study demonstrating CA9 expression in 63 patients diagnosed with SNSCC in 2013-2017. • CA9 is an independent prognostic marker for SNSCC patients who have undergone surgical treatment. • CA9 may serve as a novel therapeutic target for SNSCC. [ABSTRACT FROM AUTHOR]

To deepen the application and development of 3D Printing Construction Technology, the rheological characteristics, compressive strength and bending performance of 3D printed polyvinyl alcohol fiber (PVA fiber) reinforced cement-based material were explored. The direction of the intralayer interfaces and the fiber's distribution direction caused the anisotropy of 3D printed PVA fiber reinforced cement-based material. The printed specimens presented different failure patterns in different compressive directions, and there was certain anisotropy in the X, Y and Z directions. For the bending performance, the load-midpoint deflection curves of casted specimens and the Z x direction of printed specimens showed the strain hardening behavior, while the Z y direction of printed specimens did not. Compared with the Z y specimen, the bending strength of the Z x specimen was about 3 ∼ 4 times higher, and the peak deflection was about an order of magnitude higher. The anisotropy of the printed specimen can be used to improve the bending performance in a specific loading direction to a certain extent. • The rheological characteristics were used to characterize the Printability. • The printed specimens showed different compressive failure modes. • The direction of intralayer interfaces caused the anisotropy in bending performance. • The fiber's distribution direction also led to the bending anisotropy. • The microstructure of the printed specimen was denser than the casted specimen. [ABSTRACT FROM AUTHOR]

[Display omitted] • The co-existence of digital and analog resistive switching behaviors can be observed in BiOI nanosheets. • The synaptic memristors can be used to simulate learning-forgetting experience and Pavlov's dog experiment. • The artificial neural network based on the memristors can be emulated for image recognition with 91.15% accuracy. The emulation of the biological synapses is essential for brain-inspired computing which is expected to overcome the traditional von Neumann bottleneck. Thus, synaptic memristor with analog resistive switching (RS) is highly desirable in non-volatile memristors for future neuromorphic computing. Herein, the co-existence of digital and analog RS can be observed in two-dimensional (2D) layered BiOI nanosheets sandwiched by the top and bottom Pt electrodes. The vertical Pt/BiOI/Pt memristors demonstrate typical bipolar RS behaviors with a large ON/OFF ratio of 1.0 × 103 and long retention time up to 1.6 × 104 s under a relatively large operation voltage. When the operation voltages are reduced to 1 V, analog RS behaviors with a series of tunable resistance states can be observed. The adjustable resistance states can be utilized to emulate "learning-forgetting" experience of human brain. Repeatable long-term potentiation (LTP) and long-term depression (LTD) cycles can be implemented based on the synaptic memristors, which can be used for simulation of artificial neural network for image recognition with accuracy up to 91.15 %. Moreover, Pavlov's dog experiment is successfully emulated based on the synaptic memristors. This study suggests good prospects of the synaptic memristors based on BiOI nanosheets for future neuromorphic computing. [ABSTRACT FROM AUTHOR]

To better describe the characteristics of time series of counts such as over-dispersion, asymmetry and structural change, this paper considers a class of integer-valued self-exciting threshold autoregressive processes that properly capture flexible asymmetric and nonlinear responses without assuming the distributions for the errors. Empirical likelihood methods are proposed for constructing confidence intervals for the parameters of interest. Maximum empirical likelihood estimators, as well as their asymptotic properties, are obtained for both the cases that the threshold variable is known or not. A method to test the nonlinearity of the data is provided. As an illustration, we conduct a simulation study and empirical analysis of Pittsburgh crime data sets. [ABSTRACT FROM AUTHOR]