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The thermophysical properties, such as thermal conductivity, thermal diffusivity, specific heat capacity and linear thermal expansion of reactive powder concrete (RPC) with different steel fiber volumetric fractions are investigated by means of high temperature tests. The thermophysical characteristics of RPC with different fiber volumes under different temperatures are analyzed and compared with those of the common high-strength concrete and high-performance concrete. The empirical relationships of thermophysical properties with temperature and fiber volume are identified. By the heat transfer and solid physics methods, the microscopic physical mechanism of heat transfer process and heat conduction properties of RPC are investigated, and the theoretical formulas of specific heat capacity and thermal expansion coefficient are derived, respectively. The effects of temperature and steel fibers on the specific heat capacity and the thermal expansion coefficient are quantitatively analyzed and the discriminant conditions are provided. It is shown that the experimental results are consistent with the theoretical prediction. reactive powder concrete (RPC), thermophysical properties, high temperature, fiber reinforcement, heat conduction, specific heat capacity, thermal expansion coefficient Citation: Ju Y, Liu H B, Liu J H, et al. Investigation on thermophysical properties of reactive powder concrete.

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BackgroundThe menstrual cycle is regulated by reproductive hormones such as estrogen which has been implicated in the pathogenesis of hypertension and is associated with obesity. However, to date there has scant study of hypertension in relation to menstrual characteristics and abnormalities. We hypothesize that adverse menstrual characteristics are associated with an increase the prevalence of hypertension and that this relationship is exacerbated by obesity.MethodsOur study leverages 178,205 healthy female participants (mean age = 29) in a population-based cross-sectional study in Tianjin, China. Menstrual characteristics including menstrual cycle length and regularity, menstrual bleeding length, menstrual blood loss and dysmenorrhea were assessed by self-reported questionnaires, and hypertension was diagnosed by physician. Multiple logistic regression models were used to assess the relationships between menstrual characteristics and hypertension.ResultsNormal length menstrual cycle (OR = 1.21, 95% CI: 1.03–1.41), oligomenorrhea (OR = 1.54, 95% CI: 1.12–2.07), irregular cycle (OR = 1.54, 95% CI: 1.22–1.93), and light menstrual blood loss (OR = 1.36, 95% CI: 1.06–1.72) were associated with hypertension among women who are overweight or obese, but not among women who are normal weight. Longer menstrual bleeding duration (OR = 1.44, 95% CI: 1.24–1.67) and dysmenorrhea were associated with increased prevalence of hypertension (OR = 1.20, 95% CI: 1.14–1.41) in all young women.ConclusionsThe prevalence of hypertension is higher among women with menstrual abnormalities, and this association is modified by overweight and obesity.

BackgroundRobotically performed neurointerventional surgery has the potential to reduce occupational hazards to staff, perform intervention with greater precision, and could be a viable solution for teleoperated neurointerventional procedures.ObjectiveTo determine the indication, robotic systems used, efficacy, safety, and the degree of manual assistance required for robotically performed neurointervention.MethodsWe conducted a systematic review of the literature up to, and including, articles published on April 12, 2021. Medline, PubMed, Embase, and Cochrane register databases were searched using medical subject heading terms to identify reports of robotically performed neurointervention, including diagnostic cerebral angiography and carotid artery intervention.ResultsA total of 8 articles treating 81 patients were included. Only one case report used a robotic system for intracranial intervention, the remaining indications being cerebral angiography and carotid artery intervention. Only one study performed a comparison of robotic and manual procedures. Across all studies, the technical success rate was 96% and the clinical success rate was 100%. All cases required a degree of manual assistance. No studies had clearly defined patient selection criteria, reference standards, or index tests, preventing meaningful statistical analysis.ConclusionsGiven the clinical success, it is plausible that robotically performed neurointerventional procedures will eventually benefit patients and reduce occupational hazards for staff; however, there is no high-level efficacy and safety evidence to support this assertion. Limitations of current robotic systems and the challenges that must be overcome to realize the potential for remote teleoperated neurointervention require further investigation.

ObjectiveCystatin C (Cys C) is a marker of renal dysfunction. Prior studies have shown that blood Cys C is related to the prognosis of coronary heart disease. The aim of the present study was to evaluate the long-term prognostic impact of Cys C on acute coronary syndrome (ACS) octogenarians with diabetes mellitus (DM).MethodsWe enrolled 660 consecutive ACS octogenarians who underwent coronary angiography and were classified into two groups based on diabetes. The baseline characters and Cys C level were measured on admission. Survival curve was calculated using the Kaplan-Meier method. Multivariate Cox regression was used to identify predictors of mortality and of major adverse cardiac events (MACE) rate.ResultsThere were 223 and 398 patients in groups DM and non-DM who fulfilled the follow-up. The average follow-up period was 28 (IQR 16–38) months. Diastolic blood pressure (DBP) was lower, ratios of hypertension and chronic renal failure (CRF), fasting blood glucose, HbA1c and Cys C levels were higher in DM group than those in non-DM group (P<0.01). The cumulative survival of DM group was significantly lower than that of non-DM group in the long term (P = 0.018). All cause mortality and MACE of DM group were higher than those of non-DM group (P<0.05). The plasma Cys C concentration (OR = 3.32, 95% CI = 1.18-10.92, P = 0.023) was the uniqueness independent predictor for long-term all cause mortality. The plasma Cys C concentration (OR = 2.47, 95% CI = 1.07-7.86, P = 0.029) and Genesis score (OR = 1.01, 95% CI = 1.00-1.03, P = 0.043) were independent predictors for MACE in DM group. ROC curve analysis showed that the predictive cut-off value of Cys C for mortality of DM group was 1.605 (0.718, 0.704).ConclusionsCys C is an independent predictor for long-term mortality and MACE of ACS octogenarians with DM.

Although cardiac rupture (CR) is a fatal mechanical complication of acute myocardial infarction (AMI), to date no predictive model for CR has been described. CR has common pathological characteristics with major bleeding. We aimed to investigate the relationship between the risk factors of major bleeding and CR. A total of 10202 consecutive AMI patients were recruited, and mechanical complications occurred in 72 patients. AMI patients without CR were chosen as control group. Clinical characteristics including bleeding-related factors were compared between the groups. The incidences of free wall rupture (FWR), ventricular septal rupture (VSR), and papillary muscle rupture (PMR) were 0.39%, 0.21%, and 0.09%, respectively, and the hospital mortalities were 92.5%, 45.5%, and 10.0%, respectively. Female proportion and average age were significantly higher in the groups of FWR and VSR than in the control group (P<0.01); higher white blood cell count and lower hemoglobin were found in all CR groups (P<0.01). Compared to the control group, patients with CR were more likely to receive an administration of thrombolysis [26.39% vs. 13.19%, P<0.05], and were less likely to be treated with primary percutaneous coronary intervention (PCI) [41.67% vs. 81.60%, P<0.05]. The major bleeding scores (integer scores) of FWR, VSR, and PMR were (17.70±7.24), (21.91±8.33), and (18.60±7.88), respectively, and were significantly higher than that of the control group (11.72±7.71) (P<0.05). A regression analysis identified age, increased heart rate, anemia, higher white blood cell count, and thrombolysis as independent risk factors of CR, most of which were major bleeding-related factors. The patients with CR have a significantly higher risk of hemorrhage compared to the group without CR. Risk of CR after AMI is related to the risk of hemorrhage.

Objectives: Can addition of neurokinin-1 receptor antagonists (NK1-RAs) be considered as an ideal strategy for the prevention of chemotherapy-induced nausea and vomiting (CINV)? Researchers differ on this question. Materials and Methods: Electronic databases were searched for randomized control trials (RCTs) that evaluated the effectiveness and safety of NK1-RAs in preventing CINV. The primary end point was complete response (CR) in the acute, delayed, and overall phases after chemotherapy. Subgroup analyses evaluated the types of NK1-RAs, routines of administration, types of malignancies, regimens used in combination with NK1-RAs, and age of patients included in the studies. The incidences of different types of adverse events were also extracted to estimate the safety of NK1-RAs. Results: A total of 38 RCTs involving 13,923 patients were identified. The CR rate of patients receiving NK-RAs was significantly higher than patients in the control groups during overall phase (70.8% vs 56.0%, P<0.001), acute phase (85.1% vs 79.6%, P<0.001), and delayed phase (71.4% vs 58.2%, P<0.001). There were three studies including patients of children or adolescents, the CR rate was also significantly higher in the treatment group (overall phase: OR=2.807, P<0.001; acute phase: OR=2.863, P =0.012; delayed phase: OR=2.417, P<0.001). For all the other outcomes, patients in the NK1-RAs groups showed improvements compared to the control groups (incidence of nausea: 45.2% vs 45.9%, P<0.001; occurrence of vomiting: 22.6% vs 38.9%, P<0.001; usage of rescue drugs: 23.5% vs 34.1%, P<0.001). The pooled side effects from NK1-RAs did not significantly differ from previous reports and the toxicity rates in patients less than eighteen years old also did not diff between the two groups (P=0.497). However, we found that constipation and insomnia were more common in the patients of control groups, whereas diarrhea and hiccups were more frequently detected in patients receiving NK1-RAs. Conclusions: NK1-RAs improved the CR rate of CINV. They are effective for both adults and children. The use of NK1-RAs might be associated with the appearance of diarrhea and hiccups, while decreasing the possibility of constipation and insomnia.