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The heat transfer efficiency of a thermal energy storage unit (TESU) can be improved by the addition of novel longitudinal fins. A series of TESUs are analyzed using the finite volume method (FVM) to determine the effect of fin angle on the heat transfer performance. As the fin angle increases, the TES rate first increases, then decreases, reaching a maximum rate at 60°, where the melting time is less by 30.9%, 28.58%, 21.99%, 9.02%, and 18.1% than at 0°, 15°, 30°, 45°, and 80°, respectively. In addition, it is found that the melting time of the phase change material is significantly greater at the bottom of the TESU. The time percentage of this stage decreases as the fin angle increases through these percentages by 7%, 14%, 23%, 33%, and 20%, respectively. Further, the response surface methodology (RSM) is applied to optimize the longitudinal fin by minimizing the total melting time. The analysis concludes that a fin angle of 58.68° reduces the complete melting time of the stearic acid by 44% below the time at 0°. These findings fill a gap in knowledge of the effect on melting performance of the design angle of longitudinal fins and provide a reference for the design of horizontally placed longitudinal finned thermal energy storage units. [ABSTRACT FROM AUTHOR]

This retrospective cohort study aimed to identify baseline patient characteristics involving modifiable lifestyle factors that are associated with the development of colorectal adenomas, and establish and validate a nomogram for risk predictions among high-risk populations with negative index colonoscopy. A total of 83,076 participants who underwent an index colonoscopy at the Tianjin Union Medical Center between 2004 and 2019 were collected. According to meticulous inclusion and exclusion criteria, 249 subjects were enrolled and categorized into the primary and validation cohorts. Based on the primary cohort, we utilized the LASSO-Cox regression and the univariate/multivariate Cox proportional hazards (Cox-PH) regression parallelly to select variables, and incorporated selected variables into two nomogram models established using the multivariate Cox-PH regression. Comparison of the Akaike information criterion and the area under the receiver operating characteristic curve of the two models demonstrated that the nomogram model constituted by four covariates retained by the LASSO-Cox regression, including baseline age, body mass index, physical activity and family history of colorectal cancer (CRC) in first-degree relatives, performed better at predicting adenoma-free survival probabilities. Further validation including the concordance index, calibration plots, decision curve analysis and Kaplan–Meier survival curves also revealed good predictive accuracy, discriminating ability, clinical utility and risk stratification capacity of the nomogram model. Our nomogram will assist high-risk individuals with negative index colonoscopy to prevent colorectal adenoma occurrence and CRC morbidity with improved cost-effectiveness. [ABSTRACT FROM AUTHOR]

Objectives: With the intention of providing a reference for secondary prevention, our study provides some insight on diagnostic yield of factors influencing compliance with colonoscopy and the presence of advanced adenomas (AA). Methods: We conducted large-scale CRC screening among local Tianjin residents aged 40–75 years between 2012 and 2019. A high-risk factor questionnaire (HRFQ) was distributed to each participant, followed by the performance of a fecal immunochemical test (FIT). Participants who tested positively for any of these items were advised to undergo a colonoscopy. Relevant basic information was collected from participants during CRC screening, and the screening data were sorted and analysed. Results: A total of 5,670,924 people participated in CRC screening by the end of 2019, including 275,708 people in the high-risk group, and 74,685 (27.1%) people who underwent colonoscopy. The results of the logistic regression model demonstrated that participants with a history of mucous bloody stool (OR = 8.20, 95% CI: 7.92, 8.50, p < 0.001), chronic diarrhea (OR = 5.73, 95% CI: 5.57, 5.89, p < 0.001), and higher level of education (OR = 1.87, 95% CI: 1.80, 1.93, p < 0.001) were more likely to comply with a colonoscopy. Several factors including age (70–75 years old:OR = 3.72, 95% CI: 2.71, 5.10, p < 0.001), and FIT(+) (OR = 1.65, 95% CI: 1.42,1.90, p < 0.001) were identified to be associated with the presence of AA. Conclusions: Increased compliance with colonoscopy is urgently needed. Our findings can inform the design of future effective large-scale population-based CRC screening programmes. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is one of the most common cancers and is associated with high incidence and mortality rates worldwide. CRC has caused a tremendous loss of human health and wealth. The incidence and mortality of colorectal carcinoma are increasing in young adults. Early cancer detection and prevention are made possible through screening. At present, the faecal immunochemical test (FIT) is a noninvasive method that can be used for the large-scale clinical screening of CRC status. Therefore, this study, based on CRC screening results in Tianjin from 2012 to 2020, was conducted to analyse the major differences in diagnostic performance parameters according to sex and age. Methods: This study was based on 39,991 colonoscopies performed for individuals in the Tianjin CRC screening program from 2012 to 2020. Of these individuals, they had complete FIT and colonoscopy results. The differences in FIT results were analysed by sex and age. Results: According to this study, males were generally more likely to develop advanced neoplasms (ANs) than females, and the prevalence increased with age. Males with negative FIT results were more likely to have advanced neoplasms than females with positive results. The accuracy of the FIT in detecting ANs in each age group was 54.9%, 45.5%, 48.6% and 49.5% in the 40–49, 50–59, 60–69, and ≥ 70 age groups, respectively. Conclusions: The FIT detected ANs with highest accuracy in the 40–49 age group. Our research can provide guidance to formulate CRC screening strategies. [ABSTRACT FROM AUTHOR]

We evaluate the prognostic value of chemotherapy and other prognostic factors on overall survival among colon patients with deficient mismatch repair (dMMR), and determine the optimum time to start chemotherapy after surgery. Data of 306 colon cancer patients with dMMR who received radical surgery were collected from three Chinese centers between August 2012 and January 2018. Overall survival (OS) was assessed with the Kaplan–Meier method and log-rank. Cox regression analysis were used to assess influencing prognosis factors. The median follow-up time for all patients was 45.0 months (range, 1.0–100). There was a nonsignificant OS benefit from chemotherapy for patients with stage I and stage II disease, including high-risk stage II disease (log-rank p: 0.386, 0.779, 0.921), and a significant OS benefit for patients with stage III and stage IV disease for receiving post-operation chemotherapy (log-rank p = 0.002, 0.019). Stage III patients benefitted from chemotherapy regimens that contained oxaliplatin (log-rank p = 0.004), and Starting chemotherapy with oxaliplatin treatment earlier resulted in better outcomes (95% CI 0.013–0.857; p = 0.035). Chemotherapy regimens containing oxaliplatin can prolong the survival time of stage III and IV dMMR colon cancer patients. This beneficial manifestation was more pronounced after starting chemotherapy treatment early post operation. High risk stage II dMMR colon patients including T4N0M0 cannot benefit from chemotherapy. [ABSTRACT FROM AUTHOR]

In order to explore the utility of barium hydroxide octahydrate (BHO) in heat storage systems, high-performance composite phase change materials (CPCMs) were prepared by mixing additives. CaCO3, MgCl2·6H2O, and MgSO4 were firstly selected as nucleating agents to reduce the supercooling degree of BHO. The enhancement of thermal conductivity by nucleating agent CaF2 was quantified. Gelatin, sodium carboxymethyl cellulose, and xanthan gum (XG) were added to inhibit phase separation. It was found that 3 mass% CaF2 reduced the supercooling degree of BHO to 0.4 °C and also made the phase change platform of solidification (PCPs) temperature most stable. It was also found that 4 mass% MgCl2·6H2O prolonged PCPs by 50.2%. The CPCM with 3 mass% XG still showed supereminent suspension stability after cycling, which hindered the phase separation. Expanded graphite (EG) was used to intensify the thermal conductivity of CPCM. After the investigation of thermal properties and microstructure, it was concluded that 4 mass% EG could increase the thermal conductivity by 3.37 times. [ABSTRACT FROM AUTHOR]

In order to solve the conflict between indoor lighting and PV cells in building-integrated photovoltaic/thermal (BIPV/T) systems, a glass curtain wall system based on a tiny transmissive concentrator is proposed. This glass curtain wall has a direct influence on the heat transfer between indoor and outdoor, and the operating parameters of air and water inlet temperature, indoor and outdoor temperature, and radiation intensity have a significant influence on the heat transfer characteristics of the glass curtain wall. The 3D model is established by SoildWorks software, and the thermal characteristics of the new glass curtain wall system are simulated through computational fluid dynamics (CFD) method. Thermal performance was tested under actual weather for the winter working conditions. The CFD simulation results are verified by the test results under actual weather. The results show that thermal efficiency simulation results are in good agreement with the experimental results of the new glass curtain wall system. The simulation conditions were designed by using the orthogonal method, and the significance analysis of the influencing factors of the indoor wall surface heat gain was carried out. With the increase of the bottom heat flux and the air velocity, the heat absorption of the inner wall surface increases. When the wind speed is 0.1 m/s, the heat flow on the bottom surface rises from 500 W/m2 to 2500 W/m2, and the heat flow intensity on the interior wall changes from 10.31 W/m2 to −29.12 W/m2. Under typical working conditions, the new glass curtain wall system can reduce the indoor heat load by 47.5% than ordinary glass curtain wall. [ABSTRACT FROM AUTHOR]

Dust accumulation is one of the reasons for the performance degradation of concentrating photovoltaic and thermal (CPV/T) systems due to the deposition of dust particles with different compositions, shapes, sizes, and masses. In this work, an optical model was developed to investigate the influence of the particle size, diameter, shape, and deposition density on the light concentration efficiency, using the Monte Carlo raytracing (MCRT) method in the Tracepro software. The triangular particles had a larger influence on the light ray deflection and energy flux degradation than the circular and square particles. An average increase in the dust density of 1 g/m2 decreased the light concentration efficiency of particles with sizes smaller than 50 µm and 60 µm by 3.31% and 3.26%, respectively. Furthermore, the effect of the incidence angle on the light concentration efficiency was considered at an angle less than 2°. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to analyze the clinical characteristics of fatal adverse events (AEs) of rivaroxaban combined with aspirin and to underline the importance of the rational use of drugs. Methods: The WHO global database of reported potential side effects of medicinal products (VigiBase) was searched for fatal AEs in the combined use of rivaroxaban and aspirin, and the clinical characteristics of those cases with sufficient information (vigiGrade completeness score ≥ 0.80) were analyzed. Results: By January 19, 2020, 2309 fatal adverse event reports of rivaroxaban combined with aspirin from 21 countries were entered in VigiBase. One hundred and twenty cases contained further information, of which 42 were female (35%) and 78 were male (65%). The median age was 75 (range 34 to 93) years, and 109 cases (91%) were elderly patients (≥ 65 years). The AEs listed in the fatal case reports included bleeding in 114 cases (mainly intracranial hemorrhage and gastrointestinal hemorrhage, 59 and 46 respectively, accounting for 88%) and ischemic events in six cases (ischemic stroke in three, acute myocardial infarction in two, myocardial infarction combined with acute liver failure in one). Among the patients with bleeding events, 108 (95%) had existing risk factors for bleeding or for interacting with aspirin or rivaroxaban. These may be divided into the following: diseases (hypertension, renal impairment, history of stroke, peptic ulcer, or previous bleeding), drugs (high dose aspirin, antiplatelet drugs, anticoagulants, P-gp inhibitors/CYP3A4 inhibitors, non-steroidal anti-inflammatory drugs, steroids, and selective serotonin reuptake inhibitors), or other factors (e.g., elderly, low body weight, or excessive intake of ginger, fish oil, or alcohol). There were 45 cases with two or more of these risk factors in addition to rivaroxaban and aspirin. Patients with ischemic events are often in very high-risk groups of atherosclerotic cardiovascular disease (ASCVD) or self-discontinuation of treated drugs. Medication errors occurred in 24 patients (20%): excessive treatment in 17 cases, contraindication in three, frequency error in two, excessive treatment combined with contraindication in one, and self-discontinuation in one. Conclusions: Fatal AEs related to rivaroxaban combined with aspirin, including bleeding and ischemic events, have been reported mostly in the elderly, and sometimes involved medication errors. The fatal AEs mainly manifested as serious bleeding, and most of them occurred in patients with concurrent multiple risk factors. Monitoring coagulation during rivaroxaban treatment is recommended in very high-risk ASCVD populations, and attention should be paid to prevention of medication errors. [ABSTRACT FROM AUTHOR]

Background Geriatric outpatients with polypharmacy have a high risk of potentially inappropriate medication (PIM) use. Aim To identify differences in both prevalence and patterns of PIMs and drug-related problems (DRPs) in older outpatients who visited the tertiary hospitals (THs) and community health centers (CHCs) and analyze associated factors. Method A prospective cross-sectional study was conducted in five THs and five CHCs from September 2018 to November 2019 in Beijing, China. Data were collected from outpatients aged ≥ 65 years with chronic diseases and polypharmacy. PIMs were evaluated using the 2015 and 2019 Beers Criteria and the Screening Tool of Older Persons' Prescriptions (STOPP) criteria. DRPs were classified using the Helper-Strand DRP Classification. The prevalence and types of PIMs and DRPs were compared, and relevant factors were analyzed. Results The prevalence of PIMs based on the 2015 Beers Criteria was higher in patients from the THs, while PIMs based on the 2019 Beers Criteria did not show a significant difference. PIM prevalence based on STOPP Criteria and DRPs was higher in patients from CHCs. Visiting CHCs was an independent factor of PIMs based on the 2015 Beers Criteria (OR 0.774, 95% CI 0.604–0.992) and the STOPP Criteria (OR 2.427, 95% CI 1.883–3.128), and DRPs (OR 3.612, 95% CI 2.682–4.865). Conclusion Differences in PIM and DRP might be due to the patients and settings. Specific measures to improve the appropriateness of medications in both settings should be used. [ABSTRACT FROM AUTHOR]

The linear Fresnel reflector concentrator (LFRC) is widely used in the field of solar energy utilization due to its simple structure, low cost, and excellent wind resistance. Nevertheless, the LFRC operates outdoors all year round, and the dust accumulation on the mirror will reduce the optical efficiency of the system, so it needs to be perfected and improved. In this paper, a focal plane energy flux experimental device was designed to test the energy flux of the system under different dust accumulation times. The results indicate that, the dust density on the mirror increased and the energy flux on the focal plane decreased with increase of dust accumulation time. After undergoing dust accumulation for 35 days, the dust density on the mirror reached 4.33 g/m2 and the average energy flux on the focal plane decreased to 1.78 kW/m2. Additionally, the variation of reflectivity caused by dust accumulation on mirror was taken as the quantitative index, and a prediction model for the impact of dust on the optical efficiency of the system was proposed. The results will provide guidance for improving the optical efficiency of the LFRC. [ABSTRACT FROM AUTHOR]

The vapor compression heat pump is considered as the best option for aerospace thermal control system. The heat exchanger in vapor compression heat pump is a component that is greatly influenced by the cosmic environment. Lubricating oil enters heat pump system with a refrigerant under microgravity, and the entrance of the lubricant increases the complexity of the flow. In this work, FLUENT software was used to study the flow and lubricant deposition of a two-phase mixture of lubricant POE RL 68H and refrigerant R134a in a heat exchanger without the consideration of phase-change heat transfer. The functional relationships between the oil film thickness and the proportion of lubricating oil, the gravitational acceleration, the inlet flow velocity, and the placement directions of the two phases of oil in the heat exchanger were established. The results demonstrate that with the increase of the gravitational acceleration and the lubricating oil content, the thickness of the oil film will exhibit an S-type change in line with the Boltzmann function, and the amount of lubricating oil deposition will increase. With the increase of the flow velocity, the thickness of the oil film will exhibit an exponential decline. [ABSTRACT FROM AUTHOR]

Aim: Evaluate the effect of the Physician-Pharmacist Collaborative Management (PPCM) practice model in patients after percutaneous coronary intervention (PCI). Method: A retrospective cohort study was conducted in post-PCI patients. The study enrolled patients who underwent PCI at our hospital from May 1, 2018, to January 31, 2020. Patients were divided into two groups: the PPCM group if they utilized the Complex Coronary Interventions Medication Therapy Management (CCI-MTM) clinic and the usual care (UC) group if they used the physician-only cardiology clinic. Patients had clinic visits monthly, and data were analyzed after 6-months of follow-up. A propensity score matching (PSM) method was used to control confounding bias between groups. Results: A total of 727 patients met the inclusion criteria, including 67 patients in the PPCM group and 660 patients in the UC group. Using the 1:2 nearest neighbor matching method, 61 pairs were successfully matched; this included 61 patients in the PPCM group and 122 patients in the UC group. The proportion of patients reaching both LDL-C (73.8% versus 41.0%, P < 0.001) and heart rate (14.8% versus 4.1%, P = 0.007) goals in the PPCM was higher compared to the UC group. The median time to achieving the goal LDL-C was shorter in the PPCM group (31 days versus 126 days, P = 0.001). The utilization rates of β -receptor blockers (73.8% versus 56.6%, P = 0.005) and ACEIs or ARBs (72.1% versus 56.6%, P = 0.018) were higher in the PPCM group compared to the UC group. There was no significant difference in adverse drug events between the two groups (P > 0.05). All recommendations to resolve drug-related problems were accepted by the physicians and patients. Conclusion: The pharmaceutical care provided by the pharmacist in the PPCM clinic improved risk factor control and increased the utilization of preventive drugs in post-PCI patients. [ABSTRACT FROM AUTHOR]

Eu(NO3)3 was selected as an enhancer to improve the performance of luminescent hybrid bimodal mesoporous silica (LHMS), and a series of LHMS-EN(x) (Eu(NO3)3/1,8-naphthalic anhydridemolar ratio = x :1; x = 0, 0.1, 0.5, 1, 2, 2.5, and 5) samples were prepared. The influence of various Eu3+ amounts on the textural characteristics and luminescent performance of the LHMS-EN(x) samples were investigated. It is shown that Eu3+ ions played a role of fluorescence enhancer in this system, but various amounts of Eu3+ ions obviously influenced the luminescent intensity of the LHMS-EN(x) samples, with the LHMS-EN(1) sample displaying the highest luminescent intensity. The tendency of the luminescent intensity of the LHMS-EN(x) samples was gained and confirmed by that of the LHMS-EA(x) (Eu(CH3COO)3 as enhancer) and LHMS-EC(x) (Eu(Cl)3 as enhancer) samples. [ABSTRACT FROM AUTHOR]

Water-based ZnO nanofluids were prepared via the two-step method, and the influences of dispersant type and mass fraction on the stability and particle size distribution of the nanofluids were investigated. The spectral transmittances of the nanofluids were obtained by a UV-Vis-NIR spectrophotometer. Thermal conductivities of the nanofluids with various mass fractions were measured at different temperatures and a fitted nonlinear correlated equation was established for low-concentration application and compared with existing models. The photothermal conversion performance of the nanofluids was evaluated by theoretical and experimental methods at three optical depths. The results showed that, CTAB as the dispersant provides better physical stability of water-based ZnO nanofluids than SDBS or GA does. Effect of the temperature on the nanofluid thermal conductivity is remarkable with the increase of nanoparticle mass fraction, especially in the range 55°C to 75°C. The maximum thermal conductivity of the studied nanofluids is 0.9488 W/(m·°C) at 75°C, 43.61% higher than that of water. The minimum thermal conductivity of the studied nanofluids is 0.6376 W/(m·°C) at 25°C, 5.16% higher than that of water. The photothermal conversion performance of the nanofluids is quite good with a maximum average absorption efficiency of 0.47, 135% higher than that of water (η=0.2), and the maximum SAR is 527.5 W/g. [ABSTRACT FROM AUTHOR]

Solar reflecting and heat collecting systems are generally operated outdoors year-round, and the optical performance of the reflector is reduced by dust accumulation on the surface. In this study, the dust accumulation on a linear Fresnel reflector was investigated. The relative reflectivity of the mirror before and after dust accumulation and the physical and chemical characteristics of the dust were measured using an ultraviolet spectrophotometer, scanning electron microscope, and X-ray diffractometer. The results showed that the dust density on the mirror increased, and the relative reflectivity decreased with an increase in the dust accumulation time. During 48 days of dust accumulation, the average relative reflectivity decreased 9.4% for a 1 g/m2 increase in the dust density. Additionally, the dust density on the mirror increased while the relative reflectivity decreased with a decrease in the mirror tilt angle. The rate of decrease of the relative reflectivity was higher for the aluminum mirror than that of the silver mirror after dust accumulation. The main component of the dust particles in the test area was SiO2, and the particle size range of the dust was 0.9 um to 87 µm. According to the physical and chemical properties of the dust and the shielding effect of the dust on the mirror, a model to predict the influence of natural dust accumulation on the relative reflectivity of the linear Fresnel reflector was proposed. The predicted results deviated about 1% from the test results. [ABSTRACT FROM AUTHOR]

Background: For elderly patients who are about to undergo surgery, research on the effects of preoperative medication on postoperative outcomes is rare, especially preoperative discontinuation-requiring medication (PDRM) which needed to be discontinued because of its increased risk of postoperative complications. Aim: To investigate whether preoperative medication (PDRM and polypharmacy) is associated with postoperative length of hospital stay (LOS) in elderly patients undergoing hip fracture surgery. Methods: Patients aged ≥ 65 who were scheduled for hip (limited to femoral tuberosity) fracture surgery were included. Baseline characteristics, preoperative medication and postoperative LOS were collected from the electronic medical record. The primary outcome was postoperative LOS. Results: A total of 369 hip fracture patients were included. There were 188 and 122 patients exposed to PDRM and polypharmacy, respectively. Multivariate analysis models were constructed using significant factors for prolonged postoperative hospital stay from univariate analysis: Model I (body mass index (BMI), Charlson comorbidity index (CCI) ≥ 7, creatinine clearance rate (Ccr) < 60 and PDRM) and Model II (BMI, Ccr ≥ 7, Ccr < 60 and polypharmacy). CCI was the most significant factor. Its adjusted odds ratio was as large as 2.7 and attributable risk was 63%. In preoperative medication use, both polypharmacy and PDRM showed significant association with postoperative LOS. Conclusion: The present study supported the impact of PDRM on postoperative LOS in geriatric hip fracture patients. The results added a further aspect to preoperative medication optimization in elderly patients undergoing hip fracture surgery. [ABSTRACT FROM AUTHOR]

Carbon nanotube nanofluids have wide application prospects due to their unique structure and excellent properties. In this study, the thermal conductivity properties of carbon nanotube nanofluids and SiO2/water nanofluids were compared and analyzed experimentally using different preparation methods. The physical properties of nanofluids were tested using a Malvern Zetasizer Nano Instrument and a Hot Disk Thermal Constant Analyzer. Combined with field synergy theory analysis of the heat transfer performance of nanofluids, results show that the thermal conductivity of carbon nanotube nanofluids is higher than that of SiO2/water nanofluids, and the thermal conductivity of nanofluid rises with the increase of mass fraction and temperature. Moreover, the synergistic performance of carbon nanotube nanofluids is also superior to that of SiO2/water nanofluids. When the mass fraction of the carbon nanotube nanofluids is 10% and the SiO2/water nanofluids is 8%, their field synergy numbers and heat transfer enhancement factors both reach maximum. From the perspective of the preparation method, the thermal conductivity of nanofluids dispersed by high shear microfluidizer is higher than that by ultrasonic dispersion. This result provides some reference for the selection and use of working substance in a microchannel cooling concentrated photovoltaic and thermal (CPV/T) system. [ABSTRACT FROM AUTHOR]

Vapor compression heat pump is of great significance to space thermal control. It can effectively regulate the temperature of electronic devices to ensure proper operation. Weightlessness is a significant factor affecting the operation. Weightlessness test of vapor compression heat pump was conducted to investigate the weightless effect on its performance. Weightlessness test was achieved by free fall on a platform 60 m above the ground. The tests of continuous weightlessness and single stroke of weightlessness were presented and analyzed. The results showed that the weightlessness decreased the evaporative heat transfer performance and enhanced the condensation heat transfer performance. It is then advisable to increase heat transfer area of the evaporator in the design of future vapor compression heat pumps, and the design of condensers could still be based on the routine method adopted in ground applications. This part of experimental data for space application of vapor compression heat pump is expected to be of great significance. [ABSTRACT FROM AUTHOR]