•Volumetric solar receiver with double-layer ceramic foam is investigated.•Local thermal non-equilibrium model is adopted to solve the temperature field.•Thickness of the first porous layer affects ...the temperature field and pressure drop.•Gradual designs of porosity and mean cell size are studied.•The increasing design with large cell size gradient shows improved performance.
Using porous materials has become an effective means to enhance heat transfer. Volumetric receiver is a key component inside the solar thermal systems. The novel concept using double-layer ceramic foam holds great potential for improving the efficiency. The current study aims to investigate the effects of geometric properties of each porous layer on the thermal performance. The local thermal non-equilibrium model is adopted for energy equations of the fluid and solid phases. Radiative transfer in the foam combined the concentrated solar radiation absorption is solved with the modified P1 approximation. The results indicate that the thickness of the first porous layer has significant effect on the temperature field and pressure drop. Compared with the increasing-porosity configuration, the decreasing-porosity configuration tends to achieve higher air outlet temperature and lower solid inlet temperature. In addition, the increasing design of mean cell size shows improved performance compared to the decreasing design.
•New blanching method, vacuum-steam pulsed blanching, was employed to carrot.•Compared with HB, the VSPB treatment had higher blanching efficiency and quality.•VSPB enhanced carrot drying, ...phytochemical contents, antioxidant capacity and colour.•Ultrastructural and microstructure observations clarified the mechanism of quality enhancement.•Chlorogenic acid in blanched carrot increased more than 220 times compared to fresh samples.
An emerging blanching technology, namely vacuum-steam pulsed blanching (VSPB) was employed to blanch the carrots and its effects on blanching efficiency, microstructure and ultrastructure, drying kinetics, colour, texture, phytochemicals (phenolics and β-carotene) and antioxidant capacity of carrot slices were explored and compared with the traditional hot water blanching. Results showed that both blanching treatments enhanced the drying velocity and shortened the drying time by 25.9% compared with untreated samples. VSPB yielded higher blanching efficiency, better colour (more red and yellow), greater antioxidant capacity and higher preservation of phytochemicals compared with hot water blanched samples. Especially, compared to hot water blanched carrots, the p-hydroxybenzoic acid, ferulic acid, and caffeic acid content of VSPB samples increased of 106.6%, 42.0%, and 19.0%, respectively. Interestingly, the chlorogenic acid content in the blanched carrot increased more than 220 times compared to fresh samples. Ultrastructure and microstructure observation clarify the mechanism of quality enhancement of VSPB.
To report long‐term results of a randomized controlled trial that compared cisplatin/fluorouracil/docetaxel (TPF) induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) with CCRT alone ...in locoregionally advanced nasopharyngeal carcinoma (NPC). Patients with stage III–IVB (except T3–4 N0) NPC were randomly assigned to receive IC plus CCRT (n = 241) or CCRT alone (n = 239). IC included three cycles of docetaxel (60 mg/m2 d1), cisplatin (60 mg/m2 d1), and fluorouracil (600 mg/m2/d civ d1–5) every 3 weeks. Patients from both groups received intensity‐modulated radiotherapy concurrently with three cycles of 100 mg/m2 cisplatin every 3 weeks. After a median follow‐up of 71.5 months, the IC plus CCRT group showed significantly better 5‐year failure‐free survival (FFS, 77.4% vs. 66.4%, p = 0.019), overall survival (OS, 85.6% vs. 77.7%, p = 0.042), distant failure‐free survival (88% vs. 79.8%, p = 0.030), and locoregional failure‐free survival (90.7% vs. 83.8%, p = 0.044) compared to the CCRT alone group. Post hoc subgroup analyses revealed that beneficial effects on FFS were primarily observed in patients with N1, stage IVA, pretreatment lactate dehydrogenase ≥170 U/l, or pretreatment plasma Epstein–Barr virus DNA ≥6000 copies/mL. Two nomograms were further developed to predict the potential FFS and OS benefit of TPF IC. The incidence of grade 3 or 4 late toxicities was 8.8% (21/239) in the IC plus CCRT group and 9.2% (22/238) in the CCRT alone group. Long‐term follow‐up confirmed that TPF IC plus CCRT significantly improved survival in locoregionally advanced NPC with no marked increase in late toxicities and could be an option of treatment for these patients.
What's new?
Despite advances in the treatment of nasopharyngeal carcinoma, approximately 30% of high‐risk patients experience recurrence after treatment. Here the authors find that combining the conventional chemoradiotherapy with a triple induction chemotherapy (cisplatin/fluorouracil/docetaxel) prolonged survival of patients with locoregionally advanced cancer, even after more than 70 months of follow‐up. The combination treatment increased acute, but not late, toxicities, and the authors propose that it could present a new treatment option for this patient group.
Summary Background The value of adding cisplatin, fluorouracil, and docetaxel (TPF) induction chemotherapy to concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma is ...unclear. We aimed to compare TPF induction chemotherapy plus concurrent chemoradiotherapy with concurrent chemoradiotherapy alone in a suitably powered trial. Methods We did an open-label, phase 3, multicentre, randomised controlled trial at ten institutions in China. Patients with previously untreated, stage III–IVB (except T3-4N0) nasopharyngeal carcinoma, aged 18–59 years without severe comorbidities were enrolled. Eligible patients were randomly assigned (1:1) to receive induction chemotherapy plus concurrent chemoradiotherapy or concurrent chemoradiotherapy alone (three cycles of 100 mg/m2 cisplatin every 3 weeks, concurrently with intensity-modulated radiotherapy). Induction chemotherapy was three cycles of intravenous docetaxel (60 mg/m2 on day 1), intravenous cisplatin (60 mg/m2 on day 1), and continuous intravenous fluorouracil (600 mg/m2 per day from day 1 to day 5) every 3 weeks before concurrent chemoradiotherapy. Randomisation was by a computer-generated random number code with a block size of four, stratified by treatment centre and disease stage (III or IV). Treatment allocation was not masked. The primary endpoint was failure-free survival calculated from randomisation to locoregional failure, distant failure, or death from any cause; required sample size was 476 patients (238 per group). We did efficacy analyses in our intention-to-treat population. The follow-up is ongoing; in this report, we present the 3-year survival results and acute toxic effects. This trial is registered with ClinicalTrials.gov , number NCT01245959. Findings Between March 1, 2011, and Aug 22, 2013, 241 patients were assigned to induction chemotherapy plus concurrent chemoradiotherapy and 239 to concurrent chemoradiotherapy alone. After a median follow-up of 45 months (IQR 38–49), 3-year failure-free survival was 80% (95% CI 75–85) in the induction chemotherapy plus concurrent chemoradiotherapy group and 72% (66–78) in the concurrent chemoradiotherapy alone group (hazard ratio 0·68, 95% CI 0·48–0·97; p=0·034). The most common grade 3 or 4 adverse events during treatment in the 239 patients in the induction chemotherapy plus concurrent chemoradiotherapy group versus the 238 patients in concurrent chemoradiotherapy alone group were neutropenia (101 42% vs 17 7%), leucopenia (98 41% vs 41 17%), and stomatitis (98 41% vs 84 35%). Interpretation Addition of TPF induction chemotherapy to concurrent chemoradiotherapy significantly improved failure-free survival in locoregionally advanced nasopharyngeal carcinoma with acceptable toxicity. Long-term follow-up is required to determine long-term efficacy and toxicities. Funding Shenzhen Main Luck Pharmaceuticals Inc, Sun Yat-sen University Clinical Research 5010 Program (2007037), National Science and Technology Pillar Program during the Twelfth Five-year Plan Period (2014BAI09B10), Health & Medical Collaborative Innovation Project of Guangzhou City (201400000001), Planned Science and Technology Project of Guangdong Province (2013B020400004), and The National Key Research and Development Program of China (2016YFC0902000).
With the increase of combustion temperatures, the thermal radiation effect for hot components in the new generation of aero-engines has become a key factor in the combustion process, cooling ...structure design, and thermal protection. A radiation loading system can be used as an external heat source to simulate the real thermal environment of hot components in aero-engines. Total receiving power, as well as 3-D heat flux distribution, should better coincide with real conditions. With the aid of freeform optics and the feedback optimization method, the current study develops a concentrating-type radiation heating system fit for the leading-edge surface of a C3X turbine vane. A xenon lamp combined with a freeform reflector was optimized for controllable heat flux. A design method in the area of illumination engineering was innovatively extended for the current model. Considering the effect of polar angular radiative flux distribution of a xenon lamp, a Monte Carlo ray tracing (MCRT) method was adopted to evaluate the optical performance. Feedback modifications based on Bayesian theory were adopted to obtain the optimal shape of the FFS for target heat flux. The current study seeks a feasible way to generate 3-D heat flux distribution for complex curved surfaces, such as turbine vane surfaces, and helps to simulate the real thermal environment of hot components in aero-engines.
Fibroblast-like synoviocytes (FLS) in the synovial tissue of rheumatoid arthritis (RA) exhibit over-proliferative and aggressive phenotypes, which participate in the pathophysiology of RA. In RA, ...little is known about the nonantioxidant effect of nuclear factor erythroid 2-related factor 2 (nrf2), the master regulator of redox homeostasis. In this study, we aimed to explore the expression and upstream regulatory factors of nrf2 and revealed its functions in modulating the proliferation and invasion in RA-FLS. FLS were isolated from RA and osteoarthritis patients. Expression of nrf2 in the synovial tissues and FLS was analyzed by immunohistochemistry, real-time PCR, Western blotting, and immunofluorescence staining. Cell proliferation was examined by Cell Counting Kit-8. Cell invasion was tested by transwell assay. Phosphorylation of JNK was determined by Western blotting. The results showed that nrf2 expression in the RA synovial tissues was upregulated. TNF-α promoted expression and nuclear translocation of nrf2 in RA-FLS and increased the intracellular reactive oxygen species (ROS) level. Nrf2 nuclear translocation was blocked by ROS inhibitor N-acetylcysteine. Both knockdown of nrf2 by siRNA and inhibition of nrf2 by ML385 significantly promoted the TNF-α-induced proliferation and invasion of RA-FLS. Activation of nrf2 by sulforaphane (SFN) profoundly inhibited the TNF-α-induced proliferation and invasion of RA-FLS. Knockdown of nrf2 also enhanced the TNF-α-induced matrix metalloproteinases (MMPs) expression and phosphorylation of JNK in RA-FLS. Proliferation and invasion of RA-FLS incubated with TNF-α and nrf2 siRNA were inhibited by pretreatment with JNK inhibitor SP600125. In conclusion, nrf2 is overexpressed in synovial tissues of RA patients, which may be promoted by TNF-α and ROS levels. Activation of nrf2 may suppress TNF-α-induced proliferation, invasion, and MMPs expression in RA-FLS by inhibiting JNK activation, indicating that nrf2 plays a protective role in relieving the severity of synovitis in RA. Our results might provide novel insights into the treatment of RA.
Imaging concentrators like the parabolic trough solar concentrators have been widely employed for energy production in solar power plants. The conventional imaging solar concentrators form a ...non-uniform Gaussian distribution on receiving absorbers yielding the highest temperatures. The traditional CSP system normally truncated a peripheral region of heat flux to better use the central part. CPV/T systems using the waste heat recovery method can largely improve the total efficiency. However, for the CPV module, the coolant temperature was usually below 80 °C, which limited the applications of the thermal cycle such as the ORC system. In this article, a novel trough-type free-form secondary solar concentrator (TFSC) for PV/Thermal hybrid application has been proposed. Different from other CPV/T concepts using a combined PV panel and cooling tunnel/tube, the current concept separates the receiver in two parts. The secondary free-form reflector is generated by the geometric construction method, resulting in uniform heat flux in the edge region and high concentration in the central region. Through the ray tracing method, the optical properties have been verified. Sensitivity analysis of the concentrating structure is also conducted. The results provide supports for the design and applications of novel CPV/T systems.
In current work, the energy and exergy analysis of hot air impingement drying mushroom slices was conducted under different air temperature (55, 60, 65, 70, and 75 °C), air velocity (3, 6, 9, and ...12 m/s), and sample thickness (6, 9, and 12 mm) by the first and second law of thermodynamics. The statistical analysis results indicated that the effect of air velocity and temperature on the energy and exergy was more important than the sample thickness on it. The energy utilization and energy utilization ratio were in the range of 0.067-0.859 kJ/s and 0.087-0.34, respectively. The exergy loss and exergy efficiency was varied from 0.045-0.571 kJ/s and 0.315-0.879, respectively. Besides, the artificial neural network (ANN) was employed to predict the energy and exergy parameters. The modeling results revealed that the ANN models with arranged training algorithms and transfer function could be utilized to predict the performance of hot air impingement drying system with satisfactory accuracy.
The traditional production methods of porous magnesium scaffolds are difficult to accurately control the pore morphologies and simultaneously obtain appropriate mechanical properties. In this work, ...two open-porous magnesium scaffolds with different pore size but in the nearly same porosity are successfully fabricated with high-purity Mg ingots through the titanium wire space holder (TWSH) method. The porosity and pore size can be easily, precisely and individually controlled, as well as the mechanical properties also can be regulated to be within the range of human cancellous bone by changing the orientation of pores without sacrifice the requisite porous structures. In vitro cell tests indicate that the scaffolds have good cytocompatibility and osteoblastic differentiation properties. In vivo findings demonstrate that both scaffolds exhibit acceptable inflammatory responses and can be almost fully degraded and replaced by newly formed bone. More importantly, under the same porosity, the scaffolds with larger pore size can promote early vascularization and up-regulate collagen type 1 and OPN expression, leading to higher bone mass and more mature bone formation. In conclusion, a new method is introduced to develop an open-porous magnesium scaffold with controllable microstructures and mechanical properties, which has great potential clinical application for bone reconstruction in the future.
Summary Background The effect of the addition of adjuvant chemotherapy to concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma is unclear. We aimed to assess the ...contribution of adjuvant chemotherapy to concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone. Methods We did an open-label phase 3 multicentre randomised controlled trial at seven institutions in China. Randomisation was by a computer-generated random number code. Patients were stratified by treatment centre and randomly assigned in blocks of four. Treatment allocation was not masked. We randomly assigned patients with non-metastatic stage III or IV (except T3–4N0) nasopharyngeal carcinoma to receive concurrent chemoradiotherapy plus adjuvant chemotherapy or concurrent chemoradiotherapy alone. Patients in both groups received 40 mg/m2 cisplatin weekly up to 7 weeks, concurrently with radiotherapy. Radiotherapy was given as 2·0–2·27 Gy per fraction with five daily fractions per week for 6–7 weeks to a total dose of 66 Gy or greater to the primary tumour and 60–66 Gy to the involved neck area. The concurrent chemoradiotherapy plus adjuvant chemotherapy group subsequently received 80 mg/m2 adjuvant cisplatin and 800 mg/m2 per day fluorouracil for 120 h every 4 weeks for three cycles. Our primary endpoint was failure-free survival. We did efficacy analyses in our intention-to-treat population. Our trial is ongoing; in this report we present the 2 year survival results and acute toxic effects. This trial is registered with ClinicalTrials.gov , number NCT00677118. Findings 251 patients were assigned to the concurrent chemoradiotherapy plus adjuvant chemotherapy group and 257 to the concurrent chemoradiotherapy alone group. After a median follow-up of 37·8 months (range 1·3–61·0), the estimated 2 year failure-free survival rate was 86% (95% CI 81–90) in the concurrent chemoradiotherapy plus adjuvant chemotherapy group and 84% (78–88) in concurrent chemoradiotherapy only group (hazard ratio 0·74, 95% CI 0·49–1·10; p=0·13). Stomatitis was the most commonly reported grade 3 or 4 adverse event during both radiotherapy (76 of 249 patients in the concurrent chemoradiotherapy plus adjuvant chemotherapy group and 82 of 254 in the concurrent chemoradiotherapy alone group) and adjuvant chemotherapy (43 21% of 205 patients treated with adjuvant chemotherapy). Interpretation Adjuvant cisplatin and fluorouracil chemotherapy did not significantly improve failure-free survival after concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma. Longer follow-up is needed to fully assess survival and late toxic effects, but such regimens should not, at present, be used outside well-designed clinical trials. Funding Sun Yat-sen University Clinical Research 5010 Programme (No 2007037), Science Foundation of Key Hospital Clinical Programme of Ministry of Health PR China (No 2010–178), and Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (2010).
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