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Background: In some patients, persistent gastrointestinal symptoms like abdominal pain, nausea, and diarrhea occur as part of long COVID-19 syndrome following acute respiratory symptoms caused by SARS-CoV-2. However, the characteristics of immune cells in the gastrointestinal tract of COVID-19 patients and their association with these symptoms remain unclear. Methodology: Data were collected from 95 COVID-19 patients. Among this cohort, 11 patients who exhibited gastrointestinal symptoms and underwent gastroscopy were selected. Using imaging mass cytometry, the gastrointestinal tissues of these patients were thoroughly analyzed to identify immune cell subgroups and investigate their spatial distribution. Results: Significant acute inflammatory responses were found in the gastrointestinal tissues, particularly in the duodenum, of COVID-19 patients. These alterations included an increase in the levels of CD68+ macrophages and CD3+CD4+ T-cells, which was more pronounced in tissues with nucleocapsid protein (NP). The amount of CD68+ macrophages positively correlates with the number of CD3+CD4+ T-cells (R = 0.783, p < 0.001), additionally, spatial neighborhood analysis uncovered decreased interactions between CD68+ macrophages and multiple immune cells were noted in NPpositive tissues. Furthermore, weighted gene coexpression network analysis was employed to extract gene signatures related to clinical features and immune responses from the RNA-seq data derived from gastrointestinal tissues from COVID-19 patients, and we validated that the MEgreen module shown positive correlation with clinical parameter (i.e., Total bilirubin, ALT, AST) and macrophages (R = 0.84, p = 0.001), but negatively correlated with CD4+ T cells (R = -0.62, p = 0.004). By contrast, the MEblue module was inversely associated with macrophages and positively related with CD4+ T cells. Gene function enrichment analyses revealed that the MEgreen module is closely associated with biological processes such as immune response activation, signal transduction, and chemotaxis regulation, indicating its role in the gastrointestinal inflammatory response. Conclusion: The findings of this study highlight the role of specific immune cell groups in the gastrointestinal inflammatory response in COVID-19 patients. Gene coexpression network analysis further emphasized the importance of the gene modules in gastrointestinal immune responses, providing potential molecular targets for the treatment of COVID-19-related gastrointestinal symptoms. [ABSTRACT FROM AUTHOR]

Purpose: Chemotherapy has been the primary treatment for patients with B-cell acute lymphoblastic leukemia (B-ALL). However, there are still patients who are not sensitive to chemotherapy, including those with refractory/relapse (R/R) disease and those experiencing minimal residual disease (MRD) re-emergence. Chimeric antigen receptor-T lymphocytes (CAR-T) therapy may provide a new treatment option for these patients. Materials and Methods: Our institution conducted a single-arm prospective clinical trial (ChiCTR-OPN-17013507) using CAR-T-19 to treat R/R B-ALL and MRD re-emergent patients. One hundred and fifteen patients, aged 1-25 years (median age, 8 years), were enrolled, including 67 R/R and 48 MRD re-emergent CD19-positive B-ALL patients. Results: All patients achieved morphologic complete remission (CR), and within 1 month after infusion, 111 out of 115 (96.5%) patients achieved MRD-negative CR. With a median follow-up time of 48.4 months, the estimated 4-year leukemia-free survival (LFS) rate and overall survival (OS) rate were 68.7%±4.5% and 70.7%±4.3%, respectively. There were no significant differences in longterm efficacy observed among patients with different disease statuses before infusion (4-year OS: MRD re-emergence vs. R/R B-ALL, 70.6%±6.6% vs. 66.5%±6.1%, p=0.755; 4-year LFS: MRD re-emergence vs. R/R B-ALL, 67.3%±7.0% vs. 63.8%±6.2%, p=0.704). R/R B-ALL patients bridging to transplantation after CAR-T treatment had a superior OS and LFS compared to those who did not. However, for MRD re-emergent patients, there was no significant difference in OS and LFS, regardless of whether they underwent hematopoietic stem cell transplantation or not. Conclusion CD19 CAR-T therapy effectively and safely cures both R/R B-ALL and MRD re-emergent patients. [ABSTRACT FROM AUTHOR]

Introduction: Diabetic nephropathy (DN), distinguished by detrimental changes in the renal glomeruli, is regarded as the leading cause of death from end-stage renal disease among diabetics. Cellular senescence plays a paramount role, profoundly affecting the onset and progression of chronic kidney disease (CKD) and acute kidney injuries. This study was designed to delve deeply into the pathological mechanisms between glomerulus-associated DN and cellular senescence. Methods: Glomerulus-associated DN datasets and cellular senescence-related genes were acquired from the Gene Expression Omnibus (GEO) and CellAge database respectively. By integrating bioinformatics and machine learning methodologies including the LASSO regression analysis and Random Forest, we screened out four signature genes. The receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic performance of the selected genes. Rigorous experimental validations were subsequently conducted in the mouse model to corroborate the identification of three signature genes, namely LOX, FOXD1 and GJA1. Molecular docking with chlorogenic acids (CGA) was further established not only to validate LOX, FOXD1 and GJA1 as diagnostic markers but also reveal their potential therapeutic effects. Results and discussion: In conclusion, our findings pinpointed three diagnostic markers of glomerulus-associated DN on the basis of cellular senescence. These markers could not only predict an increased risk of DN progression but also present promising therapeutic targets, potentially ushering in innovative treatments for DN in the elderly population. [ABSTRACT FROM AUTHOR]

Introduction: The prognostic role of Wilms' tumor 1 (WT1) gene expression at diagnosis in children with B cell precursor acute lymphoblastic leukemia (BCPALL) is still controversial. Methods: We detected the WT1 transcript levels of 533 de novo pediatric BCPALL patients using TaqMan-based real-time quantitative PCR and analyzed their clinical features. Results: The WT1 transcript levels differed among the distinct molecularly defined groups, with the highest levels in the KMT2A rearrangements (KMT2A-r) group. According to the results of the X-tile software, all patients were divided into two groups: WT1/ABL ≥ 0.24% (group A) and <0.24% (group B). The proportions of patients whose age was ≥10 years old, with immunophenotype of Pro-B, belonging in high-risk group, or with minimal residual disease (MRD) ≥ 0.01% at week 12 were significantly higher in group A than in group B. In the B-other group, WT1 overexpression was an independent risk factor of overall survival (OS) rate (P = 0.042), and higher MRD ≥ 0.01% at week 12 was associated with lower OS rate (P<0.001) and event-free survival rate (P<0.001). Moreover, the subgroup analysis revealed that, in patients with initial WBC<50 × 109/L or MRD<0.1% at day 33 or MRD<0.01% at week 12 or in the standard-risk group, WT1 overexpression led to a poorer outcome in comparison with those with WT1 downexpression (P<0.05). Discussion: Therefore, pediatric BCP-ALL with WT1 overexpression had unique clinico-pathological characteristics and poor treatment response. In B-other patients, WT1 overexpression at diagnosis predicted an inferior prognosis. The WT1 gene may serve as a biomarker for monitoring residual disease in the Bother population, especially in children in the standard-risk group. [ABSTRACT FROM AUTHOR]

ATG7, one of the core proteins of autophagy, plays an important role in various biological processes, including the regulation of autophagy. While clear that autophagy drives angiogenesis, the role of ATG7 in angiogenesis remains less defined. Several studies have linked ATG7 with angiogenesis, which has long been underappreciated. The knockdown of ATG7 gene in cerebrovascular development leads to angiogenesis defects. In addition, specific knockout of ATG7 in endothelial cells results in abnormal development of neovascularization. Notably, the autophagy pathway is not necessary for ATG7 regulation of angiogenesis, while the ATG7-dependent non-autophagic pathway plays a critical role in the regulation of neovascularization. In order to gain a better understanding of the non-autophagic pathway-mediated biological functions of the autophagy-associated protein ATG7 and to bring attention to this expanding but understudied research area, this article reviews recent developments in the ATG7-dependent non-autophagic pathways regulating angiogenesis. [ABSTRACT FROM AUTHOR]

The solvability conditions for the dual matrix equation ATX + X⊤A = D are deduced by applying the singular value decomposition, and the expression of the general solution to this dual matrix equation is presented. Furthermore, the minimum-norm solution of this dual matrix equation is also provided. Finally, a numerical example is presented to show the correctness of our results. [ABSTRACT FROM AUTHOR]

In the context of the COVID-19 pandemic, this research aimed to explore the relationship between dormitory environment, learning engagement, and mental health among college students, with a special focus on college students of different gender groups. We conducted a cross-sectional survey of students from 45 universities in China. For mental health, we tested students for depression using the 5-Item WHO Well-Being Index (WHO-5). The dormitory environment is exemplified by a typical four-person dormitory layout in China, which is assessed in four main areas: site location, functional layout, maintenance management, and view from the window. Meanwhile, we examined the relationship between mental health and the dormitory environment using learning engagement as a mediating variable. We found that the dormitory environment positively influences college students’ mental health through the mediating role of learning engagement. We found gender differences in mental health among Chinese college students. The mental health of male students was better than that of female students. More importantly, we found differences in the influence of dormitory environment on the mental health of college students in different gender groups. In the dormitory environment-learning engagement pathway, the influence was more pronounced for male students. In the learning engagement— mental health pathway, the total and indirect effects were more substantial for women than for men. As our study took place during the epidemic, the examination of the relationship between dormitory environment and college students’ mental health in this study will also inspire college administrators to pay more attention to the dormitory environment and support the development of public health policies to promote college students’ mental health. We encourage further research on the relationship between dormitory environment and college students’ mental health, which will promote the greening of college dormitories and improve college students’ mental health. [ABSTRACT FROM AUTHOR]

In recent decades, water scarcity is a significant constraint for socioeconomic development and threatens livelihood in an agriculture-based developing country like Pakistan. The water crisis in the country is projected to exacerbate in the coming years, especially in the southern parts. This dire situation calls for an investigation of major droughts, associated water scarcity, and changes in teleconnection patterns over Southern Pakistan. Moderate to low Southeastern monsoon (SEM) precipitation triggered the extreme drought episode (2017--2020) over Southern Pakistan and intensified the water scarcity. This study explored the severity of the respective drought event, underlying mechanisms, and changes in water scarcity over Southern Pakistan. To investigate the future changes (1980--2050) in water scarcity, coupling models (global hydrological models (GHMs)-global climate models (GCMs)) have been used to achieve the interannual performance of water availability and total water consumption. Besides, future scenarios used in this study are the combinations of SSPs and RCPs, including middle-of-the-road (SSP1-RCP4.5) and fossil-fueled development (SSP2-RCP8.5). The findings indicated a precipitation deficit of 45% during the 4-year (2017--2020), depicting the worst events in the past 50 years. South Pakistan observed the worst SEM droughts over the last 50 years, as 2000--2005 was the worst drought (precipitation deficit of 75%), followed by 2017--2020 with a 49% of precipitation deficit. Water scarcity was exacerbated by the extreme dry spells that developed over most of southern Pakistan between 2017 and 2020 as a result of moderate-to- exceptionally low SEM precipitation. Furthermore, this drought episode was accompanied by the cool phase in the Pacific and equatorial Indian Oceans. The future changes in water scarcity over the southern regions of Pakistan present a sharp increase under the SSP2-RCP8.5 scenario and are anticipated to be intensified in already stressed regions. This research is essential for environmentalists, and water resources managers, and provided crucial information to identify the hot spot areas in the target region so that water scarcity problems could be reduced in the future. [ABSTRACT FROM AUTHOR]

The solvability conditions for the dual matrix equation AXB = D and a pair of dual matrix equations AX = C and XB = D are deduced by applying the singular value decomposition, and the expressions of the general solutions to these dual matrix equations are provided. Furthermore, the minimum-norm solutions of these dual matrix equations are provided. Finally, two numerical experiments are given to validate the accuracy of the results obtained. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the expression and treatment of chemokine CXCL12 and its receptor CXCR4/CXCR7. Methods: The liver cirrhosis hypersplenism model of rats was made with CCL4, and then was detected by immunohistochemistry, Western blot and qRT-PCR. Results: The area of spleen fibrosis in the model group was significantly larger than that in the control group (p < 0.01), and the expression of CXCL12, CXCR4 and CXCR7 in the model group was significantly higher than that in the control group (p < 0.01). Conclusions: CXCL12-CXCR4/CXCR7 is abnormally high in splenic fibrosis, and blocking its high expression can slow down the occurrence of hypersplenism. [ABSTRACT FROM AUTHOR]

Allergic diseases (AD) are significant and hence rapid and accurate immunoglobulin E (IgE) determination is critical for diagnosis and treatment. Herein, a rapid, sensitive, and quantitative immunochromatographic test strip was designed for assaying IgE in human serum based on laboratory-constructed time-resolved fluorescent nanospheres (LTRFNs) which have large specific surface areas and multiple carboxyl groups in the outer layer with efficient coupling to the antibodies. Using the stable fluorescence created by the LTRFNs, the test strip accurately quantified IgE for early diagnosis with a detection limit of 4.2 ng/mL. The test strip has a long working range from 8 to 1024 ng/mL, and excellent performance, including high sensitivity, good inter-batch repeatability, and stability. Furthermore, the analysis of 30 clinical serum samples showed good correlation with a commercial chemiluminescence protocol. Therefore, the laboratory-constructed test strip has potential as a novel tool for clinical diagnosis and a rapid home test for allergic diseases. [ABSTRACT FROM AUTHOR]

Progression of leaf senescence consists of both degenerative and nutrient recycling processes in crops including wheat. However, the levels ofmetabolites in flag leaves in spring-cultivated wheat, as well as biosynthetic pathways involved under different nitrogen fertilization regimes, are largely unknown. Therefore, the present study employed a widely untargeted metabolomic profiling strategy to identify metabolites and biosynthetic pathways that could be used in a wheat improvement program aimed at manipulating the rate and onset of senescence by handling spring wheat (Dingxi 38) flag leaves sampled from no-, low-, and highnitrogen (N) conditions (designated Groups 1, 2, and 3, respectively) across three sampling times: anthesis, grain filling, and end grain filling stages. Through ultrahighperformance liquid chromatography--tandem mass spectrometry, a total of 826 metabolites comprising 107 flavonoids, 51 phenol lipids, 37 fatty acyls, 37 organooxygen compounds, 31 steroids and steroid derivatives, 18 phenols, and several unknown compounds were detected. Upon the application of the stringent screening criteria for differentially accumulated metabolites (DAMs), 28 and 23 metabolites were differentially accumulated in Group 1_vs_Group 2 and Group 1_vs_Group 3, respectively. From these, 1-O-Caffeoylglucose, Rhoifolin, Eurycomalactone;Ingenol, 4-Methoxyphenyl beta-D-glucopyranoside, and Baldrinal were detected as core conserved DAMs among the three groups with all accumulated higher in Group 1 than in the other two groups. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that tropane, piperidine, and pyridine alkaloid biosynthesis; acarbose and validamycin biosynthesis; lysine degradation; and biosynthesis of alkaloids derived from ornithine, lysine, and nicotinic acid pathways were the most significantly (p < 0.05) enriched in Group 1_vs_Group 2, while flavone and flavonol as well as anthocyanins biosynthetic pathways were the most significantly (p < 0.05) enriched in Group 1_vs_Group 3. The results from this study provide a foundation for themanipulation of the onset and rate of leaf senescence and N remobilization in wheat. [ABSTRACT FROM AUTHOR]

Introduction: Patients with malignant brain tumors frequently exhibit hypercoagulation and are at a high risk of postoperative thrombosis-related complications. However, the risk factors for postoperative thrombosis-related complications remain unclear. Methods: In this retrospective, observational study, we consecutively enrolled elective patients undergoing resection of malignant brain tumors from 26 November 2018 to 30 September 2021. The primary objective of the study was to identify risk factors for a composite of three major adverse events including postoperative lower limb deep venous thrombosis, pulmonary embolism, and cerebral ischemia. Results: A total of 456 patients were enrolled in this study, where 112 (24.6%) patients had postoperative thrombosis-related complications, 84 (18.4%) with lower limb deep venous thrombosis, 0 (0.0%) with pulmonary embolism, and 42 (9.2%) with cerebral ischemia. In a multivariate model, age more than 60 years (OR: 3.98, 95% CI: 2.30-6.88, P < 0.001), preoperative abnormal APTT (OR: 2.81, 95% CI: 1.06-7.42, P = 0.037), operation duration longer than 5 h (OR: 2.36, 95% CI: 1.34-4.16, P = 0.003), and admission to ICU (OR: 2.49, 95% CI: 1.21-5.12, P = 0.013) were independent risk factors of the postoperative deep vein thrombosis. Intraoperative plasma transfusion (OR: 6.85, 95% CI: 2.73-17.18, P < 0.001) was associated with significantly increased odds of deep vein thrombosis. Conclusion: Patients with craniocerebralmalignant tumors have a high incidence of postoperative thrombosis-related complications. There is an increase in the odds of postoperative lower limb deep venous thrombosis in patients; over 60 years old, with preoperative abnormal APTT, undergoing surgeries longer than 5-h, admission to ICU, or receiving intraoperative plasma infusion. Fresh frozen plasma infusion should be used more cautiously, especially in patients with a high risk of thrombosis. [ABSTRACT FROM AUTHOR]

Ischemia with non-obstructive coronary artery (INOCA) is a blind spot of coronary artery disease (CAD). Such patients are often reassured but offered no specific care, that lead to a heightened risk of adverse cerebrovascular disease (CVD) outcomes. Epicardial adipose tissue (EAT) is proven to correlate independently with CAD and its severity, but it is unknown whether EAT is a specific and sensitive indicator of INOCA. This review focuses on the INOCA epidemiology and related factors, as well as the association between EAT [ABSTRACT FROM AUTHOR]

Introduction: Patients underwent peroral endoscopic myotomy (POEM) for treating achalasia suffered with mild to moderate, sometimes even severe postoperative pain. Aim: To evaluate the efficacy of oxycodone on postoperative analgesia of patients undergoing PEOM. Material and methods: In this prospective, double-blinded, randomized, controlled trial, patients with achalasia were recruited and received 0.08 mg/kg oxycodone or morphine 15 min before the end of the POEM procedure. The short-form McGill questionnaire (SF-MPQ) was used to measure the postoperative pain at 0, 2, 6, 24, and 48 h after surgery, which included the visual analogue scale (VAS), the present pain intensity (PPI) scale, and the pain rating index (PRI). Results: A total of 73 patients were included, of whom 36 received oxycodone, and 37 received morphine. Compared with morphine, patients received oxycodone were associated with lower VAS in the first 24 h postoperatively (1.64 ±0.76 vs. 2.14 ±1.23, p = 0.042) as well as PPI at 2 h (1.11 ±0.40 vs. 2.22 ±0.89, p < 0.001), 6 h (1.42 ±0.55 vs. 2.08 ±0.92, p < 0.001) and 24 h (1.06 ±0.23 vs. 1.30 ±0.46, p = 0.006). Patients who received oxycodone experienced lower sensory McGill pain score than those who received morphine at 2, 6, 24, and 48 h after surgery (p < 0.05). Significantly lowered affective McGill pain score was observed in the oxycodone group at 0, 2, and 24 h postoperatively. Regarding the PRI, the sum of both sensory and affective McGill pain scores, patients with oxycodone therapy were associated with better scores postoperatively. Conclusions: Oxycodone appears to be superior to morphine in dealing with post-POEM pain, which has distinct visceral pain characteristics. [ABSTRACT FROM AUTHOR]

With the shortage of fossil energy, more attention is paid to two-phase flow due to the high heat transfer efficiency and uniform surface temperature. However, flow distribution in parallel channels is more complex than that of single-phase flow, which usually leads to heat transfer deterioration. Thus, a 3D numerical model of flow distribution and heat transfer of two-phase flow in parallel channels is developed and validated in the present study. The effect of channel cross section was investigated, and three typical cross section shapes are discussed. The results show that the flow distribution in parallel channels of the triangular cross section is the worst, and of the circular section is the best. Similarly, the heat transfer performance of the circular channel is the best because the bubbles are difficult to separate at the junction of adjacent channel surfaces in the rectangular and triangular channel. Besides, flow distribution in the U-type heat exchanger is better than that in the Z-type heat exchanger. [ABSTRACT FROM AUTHOR]

The supercritical CO2 Brayton cycle is widely utilized by various industries because of its compactness and efficiency. However, in the actual process, there are always temperature fluctuations that affect the normal operation of the whole supercritical CO2 Brayton cycle system, in order to weaken the temperature fluctuations without adding additional components, a new structure of PCHE with PCM embedded in PCHE was designed in this study. Fluent was used to simulate the working conditions and compare with the commonly used PCHE under the same working conditions. It was found that the structures with porosity of 0.8 to 0.9, the percentage reduction of temperature fluctuations on the hot side was 26.84 %, 26.78 % and 26.49 %, respectively, and the percentage reduction of temperature fluctuations on the cold side was 40.30 %, 40.81 % and 41.63 %, respectively, and the percentage reduction of heat exchange was 1.8 %, 1.9 % and 2.3 %, respectively. [ABSTRACT FROM AUTHOR]

The liquid lead-bismuth eutectic (LBE) is an ideal primary coolant for the fourth-generation advanced nuclear systems. Due to its special physical properties, especially the low Prandtl number and high density, the natural convection phenomenon caused by buoyancy is significant. In this study, a circular tube is three-dimensionally modeled to predict the flow and heat transfer process of LBE. On the base of the model validation, simulations of the uniformly heated tube with/without buoyancy are performed. The different thermal-hydraulic performance obtained under different tube arrangements and operating parameters are compared, and the effects of buoyancy on the convective heat transfer of LBE are discussed. The results show that for LBE flow with smaller Reynolds numbers, convective heat transfer is significantly enhanced when gravity is opposite to the flow direction, while the same gravity and flow direction slightly weakens the convective heat transfer capacity. For the higher Reynolds number LBE flow, the buoyancy impact and the tube arrangement can be ignored. When the tube is placed horizontally, the heat transfer coefficient of the lower wall is about three times that of the upper wall. For different engineering applications, an appropriate arrangement is necessary to improve the efficiency of heat exchanger. This study may contribute to the development and application of LBE-cooled reactors. [ABSTRACT FROM AUTHOR]

The results of numerical research on boiling heat transfer of R410A refrigerant in an elliptic tube with four microchannels and micro fins are presented in this paper. The boiling performance of elliptic microchannel tubes with different inlet vapor qualities is studied, keeping saturation temperature constant at 278.15 K corresponding to the saturation pressure at 93,623 Pa with 3 kW/m² heat flux and 150 kg/(m²s) mass flux. The Martinelli parameter, heat transfer coefficient, pressure drop, and so on are investigated in the present paper. The CFD results are compared with and verified by the previous two-phase heat transfer correlations. The discrepancies in flow rate, heat transfer performance, and two-phase flow pattern between the middle and the two sides of the elliptic tube are compared. The velocity field and flow trajectory of gas-liquid two-phase flow in the elliptic tube microchannels are discussed and analysed. The results show that when the inlet vapor quality is high, there will be a distinct heat transfer deterioration area in the microchannels during the boiling process. The large area of gas film can weaken the heat transfer performance of the microchannel heat exchanger up to 35.42 % in the region without micro fin. The local highest heat transfer coefficient can reach 2,886.8 W/(m²K) in the physical model. The micro fins can not only increase the heat transfer area and enhance the nucleate boiling but also divide the gas film to form a local annular flow pattern and inhibit the deterioration of boiling heat transfer. The present paper is of great significance for scientific utilization and optimization of the heat exchanger, the reduction of energy consumption, and the enhancement of the exergy efficiency of the system. [ABSTRACT FROM AUTHOR]

This paper presents the evaluation of a multisite statistical weather generator (MulGETS: Multisite weather Generator of École de Technologie Supérieure) based on its simulation effect of precipitation in the Yangtze River Basin. MulGETS effectively generates spatially correlated sequences of precipitation simultaneously, while maintaining their spatial and temporal distribution characteristics. On the spatial scales, the accuracy of the model varies from station to station, and in general, the errors are lower at stations in the middle and lower reaches of the Yangtze River Basin than in the upper reaches. This difference is likely to exist because of the lower amount of rainfall and more complex topography than those of the upper river basins. On the temporal scales, the simulated values are more precise on the annual scale than on the seasonal scale. Large relative errors occur more frequently in winter, ranging from -35% to 25%. MulGETS can consistently produce precipitation by considering the intensity, magnitude, and duration indices with sub-basin varied observations. However, the precipitation maxima were much lower than the observations. This work shows the general reasonability of the model in downscaling precipitation in the Yangtze River Basin. [ABSTRACT FROM AUTHOR]

This work presents a one-step synthesis of monodisperse nano-flowers by aqueous polymerization-induced self-assembly (PISA), modulated by host-guest interactions. Owing to the low monomer swelling of nanoparticles restricted by host-guest complexation, hierarchical surficial micellar structures were generated at the outer surface of the vesicles, forming fractal nanoflowers with a diameter polydispersity as low as 1.01. Our method allows the straightforward synthesis of monodisperse hierarchical nano-particles for a wide range of applications. [ABSTRACT FROM AUTHOR]

Czech-Chinese Project Transmission Enhancement and Energy Optimised Integration of Heat Exchangers in Petrochemical Industry Waste Heat Utilisation is a joint project of Czech Republic, SPIL, Brno University of Technology – VUT Brno and the People‘s Republic of China, Xi’an Jiaotong University, Xi’an, Shaanxi. The 3 y project contributes to solving the energy situation and reduction of emissions. The use of low-grade heat is an effective means of saving energy and reducing greenhouse gases, which is increasingly sought after both for large companies also in local industrial facilities and even households. It has been increasing the emphasis on the use of low-potential energy results in increased demand for sophisticated heat exchangers. Methods, standards and the creation of modular structures optimised for different outputs based on the practical use of research results are being developed for various sources of waste heat, types of circulating media and technical operating parameters. Layout and construction designs allow designers to professionally design and manufacture suitable heat exchangers for specific conditions of the production process from the very beginning and a wide scope of conditions and requirements. Utility models and software modules were created and supported with research publications. [ABSTRACT FROM AUTHOR]

The supercritical carbon dioxide Brayton cycle has become the choice of a wide range of users because of its higher efficiency and smaller turbine size, and is often used in space vehicles, sodium cooled fast reactors, Marine power equipment and other energy storage and power generation applications. However, in the process of use, the detachment of the load is a common problem, if not well handled often cause the system to crash. In this paper, based on the software Simulink in MATLAB, the moment of inertia of turbine and generator is regarded as fixed value, the key parameter differential equations of Brayton cycle are derived, and the dynamic recompression and intercooling Brayton cycle models are established. The response parameters of the system after load disconnection and different time tie-back are studied. The responses of key parameters of the system after load detachment were obtained. It was found that the recompression model had higher stability under load detachment and tie-back conditions than the intercooling model, and the length of parameter variation after load detachment was linear. The earlier the tie-back was, the faster the system could restore stability. [ABSTRACT FROM AUTHOR]

With the increasing demand for natural gas in the world, ensuring the safety and stability of pipeline transportation of natural gas has become an important subject. Compared with the studies focused on the erosion of single bend, T-pipe, and U-pipe, the studies on the continuous bend in different directions are scarce. In this paper, the model is characterized by three straight pipes with the same length and directions along the Z, Y, and X axes of the Cartesian coordinate system. The numerical simulation of gas-solid two-phase flow under different gas to solid mass ratios in the continuous bent pipeline is carried out by selecting the Oka erosion model. The results indicate that the velocity distribution of the second bend is different from that of the first bend. With the change of flow deflection angle and the accumulation of the centrifugal force, the shape of the velocity contours in the second bend turns from “basin” into a "comma" and the velocity experiences a process including rapid increase, slow decrease, gradual increase, and steep decrease. When the flow rate is 12.5 m/s, the maximum speed of the second bend is about 5 % greater than that of the first bend. Instead of a “straight-line” shape in the erosion area of the first bend, the second presents a "feather" shape. As the flow rate increases gradually, the shape characteristics of the "feather" erosion zone change from "short and dense" to "long and loose". Besides, the maximum erosion rate of the second bend is greater than that of the first even about 1.52 times. Finally, according to the simulation results, the protection suggestion of the continuous elbow is given. [ABSTRACT FROM AUTHOR]

This document is a corrigendum for an article titled "Recent and projected changes in water scarcity and unprecedented drought events over Southern Pakistan." The correction addresses an error in the funding statement of the article, providing the correct funding information. The authors express their gratitude for the financial support and state that the correction does not affect the scientific conclusions of the article. The document also includes a note from the publisher, stating that the claims expressed in the article are solely those of the authors and do not necessarily represent the views of their affiliated organizations or the publisher. The authors and their affiliations are listed at the end of the document. [Extracted from the article]

Two carboxylate-bridged one-dimensional chain complexes, {[MnII(MeOH)2][FeIII(L)2]2}n (1) and {[MnII(DMF)2][MnIII(L)2]2·DMF}n (2) [H2L = ((2-carboxyphenyl)azo)-benzaldoxime], containing a low-spin [FeIII(L)2]− or [MnIII(L)2]− unit were synthesized. Magnetic measurements show that the adjacent high-spin MnII and low-spin MIII ions display weak antiferromagnetic coupling via the syn–anti carboxyl bridges, with J = −0.066(2) cm−1 for complex 1 and J = −0.274(2) cm−1 for complex 2. [ABSTRACT FROM AUTHOR]

We report a potential way to effectively improve the magnetic properties of BiFeO3 (BFO) nanoparticles through Mg2+ ion substitution at the Fe-sites of BFO lattice. The high purity and structural changes induced by Mg doping are confirmed by X-ray powder diffractometer and Raman spectra. Enhanced magnetic properties are observed in Mg substituted samples, which simultaneously exhibit ferromagnetic and superparamagnetic properties at room temperature. A physical model is proposed to support the observed ferromagnetism of Mg doped samples, and the superparamagnetic properties are revealed by the temperature dependent magnetization measurements. The improved magnetic properties and soft nature obtained by Mg doping in BFO nanoparticles demonstrate the possibility of BFO nanoparticles to practical applications. [ABSTRACT FROM AUTHOR]

Manganese (MnFe2O4) nanoparticles are prepared via a facile solvothermal method. The electromagnetic properties are investigated in 1-18 GHz, indicating the MnFe2O4 nanoparticles are the promising materials to be applied as microwave absorbers. The wave absorbing mechanism can be attributed to the dielectric loss, magnetic loss, and the synergetic effect. The permittivity dispersion behavior is explained by Debye dipolar relation expression. The complex permeability is analyzed using Landau-Lifshitz-Gilbert equation. Natural resonance, exchange resonance, and eddy current loss arise at different frequencies. [ABSTRACT FROM AUTHOR]

Heat exchanger network (HEN) retrofit is an effective way to reduce energy consumption and improve energy efficiency. A key criterion in industrial practice to evaluate the performance of a retrofit plan is the minimising total annualised cost. However, when pursuing the goal of minimising total annualised cost by graphical tools, sub-optimal solutions are inevitable because of the difficulty in finding the balance of utility cost and investment. In this study, a method based on constrained particle swarm optimisation (PSO) algorithm is developed for the annual cost minimisation when retrofitting HENs. The proposed method is applied based on an initial retrofit plan obtained by graphical tools. It can achieve the aim of total annualised cost reduction by adjusting the inlet and outlet temperatures of each heat exchanger through PSO with the consideration of different utility prices and investment. The results show that this method can find optimal temperature spans for heat exchangers to reduce the total annualised cost. [ABSTRACT FROM AUTHOR]

The Brayton cycle system has a wide range of applications, including ship waste heat utilization, space reactors, sodium-cooled fast reactors, megawatt nuclear power systems and aerospace. The circulating temperature and circulating medium also vary with the specific application environment. The heat source temperature is usually between 700 K and 2,100 K. The commonly used working medium includes SCO2, helium and nitrogen. At present, the research and analysis of some parameters in a given working fluid and temperature are applied to specific engineering. According to the environment temperature and working medium, based on MATLAB software, the numerical model of the Brayton cycle under different working conditions is established. In addition, other calculation software is used for programming calculation to obtain the analysis results of temperature change conditions and the comparison of different conditions, providing reference and selection basis for the application of Brayton cycle in practical engineering, so that the most suitable Brayton cycle working medium and cycle model can be selected under specific conditions. The influence of changing the heat exchanger into phase change heat exchanger on the instability of the heat source is analyzed. In this paper, the thermal efficiency curves between 716 K and 2,116 K of the heat source of Brayton cycle for helium, SCO2 and nitrogen under four different cycle efficiencies were calculated, and the thermal efficiency curves of Brayton recompression cycle for helium, SCO2 and nitrogen under different extraction ratios were calculated. And the temperature changes of four different models in three working media (helium, nitrogen and SCO2) with thermal cycle efficiency were compared. [ABSTRACT FROM AUTHOR]

Heat exchanger network (HEN) retrofit has been widely studied to achieve energy savings. Different types of heat exchangers such as shell and tube, double-pipe, spiral plate, and spiral tube have their working temperature ranges and prices. However, considering the type of heat exchangers in the HEN retrofit process is rarely seen in previous publications. Selecting suitable types of heat exchangers according to their temperature ranges and prices is a crucial aspect in industrial implementation. The above-mentioned issue can be solved by the proposed Shifted Retrofit Thermodynamic Grid Diagram with the temperature range of heat exchangers (SRTGD-TR). The aim is to minimise the total cost, including utility cost and capital cost. The methodology is illustrated using a case study. [ABSTRACT FROM AUTHOR]