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Practical engineering optimization problems are characterized by high dimensionality, non-convexity, and non-linearity, and the use of optimizers to provide better quality solutions to the target problem in an acceptable time is a hot research topic in the field of optimal design. In this paper, inspired by the Sturnus vulgaris escape behavior, a Sturnus Vulgaris Escape Algorithm (SVEA) is proposed to provide a high-performance optimizer for complex optimization problems. The algorithm is composed of exploration and exploitation strategies, controlled by fixed parameters. The exploration strategies include the High-Altitude Escape Strategy and Wave Escape Strategy 1, while the exploitation strategies consist of the Cordon Line Strategy and Wave Escape Strategy 2. The High-Altitude Escape Strategy enhances exploration capabilities by reorganizing subgroups, preventing the leader and optimal individuals from overlapping, and avoiding collisions between individuals. The Cordon Line Strategy conducts refined searches around high-value regions, further improving optimization precision. Wave Escape Strategies 1 and 2 help the population escape local optima and prevent over-spreading. The performance of SVEA is evaluated through the employment of 23 benchmark test functions and the CEC2017 test set, with a subsequent comparison undertaken with nine statE − of-thE − art meta-heuristic algorithms. The outcomes of this evaluation demonstrate that SVEA attains the top ranking and is identified as the best-performing algorithm across all test sets. A statistical analysis reveals that the SVEA solution set exhibits superior performance in comparison to the other algorithms, with the discrepancy in performance being deemed to be statistically significant. Finally, the algorithm is applied to five real-world engineering problems, all providing optimal solutions while satisfying the constraints.

This study aimed to investigate the tribological properties and lubrication mechanisms of three cycloalkane carboxylic acids (cyclopropane, cyclobutane, and cyclopentane) as additives in PAO4 base oil. The testing was conducted in a TiN/steel tribosystem under ball-on-flat reciprocating sliding motion with a maximum contact pressure of 0.9 GPa. Notably, cyclopropane carboxylic acid exhibited excellent anti-friction and anti-wear properties, achieving a microscale coefficient of friction of 0.008 and a wear rate of only 7.0 × 10−8 mm3/N·m. XPS and Raman analyses of the tribofilms revealed that all three cycloalkane carboxylic acids underwent tribochemical reactions during frictional motion to form carbon-based tribofilms with varying contents. Moreover, cyclopropane carboxylic acid exhibited significant tribochemical reactions, forming carbon-based tribofilm with superior tribological properties. This behavior can be attributed to the stability and size of the carbon ring in cycloalkane, which influences its dissociation and the formation of carbon-based tribofilm under high-temperature and contact stress conditions.

Pipeline fittings with ferrules are applied to connect sections of hydraulic pipelines in aircraft, and their reliability and stability are essential. This paper aims at investigating the influence of internal fluid on the sealing characteristics of pipeline fittings by employing the multiscale model. Changes in the sealing characteristics induced by the fluid pressure switch are studied, and the assembly method under the internal fluid is also explored. The calculated results show that the multiscale model can accurately reflect the changes in the sealing area, and the high-pressure fluid can enhance the sealing reliability. Compared with the contact area, the fluid pressure exerts a greater influence on the change in the area of the high-stress zone. Furthermore, the unrestored sealing area enlarges with the increased maximum fluid pressure, and the change in the area of the high-stress zone is significantly larger than that in the contact area. Moreover, the optimum assembly position of ferrule decreases with the increase in fluid pressure, thus achieving the excellent sealing characteristics.

Renal ischemia–reperfusion (IR) injury and cyclosporine A (CsA) nephrotoxicity affect allograft function and survival. The prolonged effects and underlying mechanisms of erythropoietin derived cyclic helix B peptide (CHBP) and/or caspase-3 small interfering RNA (CASP-3siRNA) were investigated in mouse kidneys, as well as kidney epithelial cells (TCMK-1), subjected to transplant-related injuries. Bilateral renal pedicles were clamped for 30 min followed by reperfusion for 2 and 8 weeks, with/without 35 mg/kg CsA gavage daily and/or 24 nmol/kg CHBP intraperitoneal injection every 3 days. The ratio of urinary albumin to creatinine was raised by IR injury, further increased by CsA and lowered by CHBP at 2, 4, 6 and 8 weeks, whereas the level of SCr was not significantly affected. Similar change trends were revealed in tubulointerstitial damage and fibrosis, HMGB1 and active CASP-3 protein. Increased apoptotic cells in IR kidneys were decreased by CsA and CHBP at 2 and/or 8 weeks. p70 S6 kinase and mTOR were reduced by CsA with/without CHBP at 2 weeks, so were S6 ribosomal protein and GSK-3β at 8 weeks, with reduced CASP-3 at both time points. CASP-3 was further decreased by CHBP in IR or IR + CsA kidneys at 2 or 8 weeks. Furthermore, in TCMK-1 cells CsA induced apoptosis was decreased by CHBP and/or CASP-3siRNA treatment. Taken together, CHBP predominantly protects kidneys against IR injury at 2 weeks and/or CsA nephrotoxicity at 8 weeks, with different underlying mechanisms. Urinary albumin/creatinine is a good biomarker in monitoring the progression of transplant-related injuries. CsA divergently affects apoptosis in kidneys and cultured kidney epithelial cells, in which CHBP and/or CASP-3siRNA reduces inflammation and apoptosis.

Transforming carbon dioxide (CO2) into value-added fuels is an innovative way to address both the energy and the climate issues. In particular, formic acid, as formate salt, is recently attracting attention because this acid can be used as a chemical fuel in fuel cells. Here we present a novel method for hydrogenating CO2-containing industrially relevant salts, such as sodium bicarbonate ammonium bicarbonate and ammonium carbonate, to formate. Metal sodium (Na0) was used as the reducing agent to break the C–O bond and as a inducer of hydrogen transfer. A ball-milling mechanochemical method was used for the solid-phase reaction. Results show that reducing (NH4)2CO3(s) with sodium yielded 41.4% formate after 7 h under catalyst-free conditions. Our new method has thus promising potential applications in the emerging CO2 economy.

Although polymer-based nanocomposites have great application potential in many fields, compared with the application of ferroelectric nanocomposites in functional microscale structures and devices, especially in the field of photonics microdevices fabricated by laser processing, the development of polymer-based nanocomposites is relatively lagging behind. In this study, the polyvinylidene fluoride ferroelectric composite material was taken as the research object, and the preparation method of polymer nanocomposite material suitable for laser microstructure processing was solved by exploring the material functionalization method. The control of the optical properties of polyvinylidene fluoride ferroelectric composites was achieved through material design, control of the size of nanoparticles in the prepared polymer nanocomposites, and characterization of their structures and properties. Two-dimensional and three-dimensional structures of polymer nanocomposites were prepared by laser microstructure processing technology, and the optical properties of the microstructures were evaluated. When the applied stress field was zero, the macroscopic coercive field was larger, and the hystereswas loop was wider, while the butterfly curve changed rapidly near the coercive field, and the strain was negative. From the test results of the scanning electron microscope, it can be concluded that the lowest average power to find ablation traces was 0.06 mw, and the affected area was very small, and there was no damage to the surrounding nanotubes. Therefore, this paper believes that the damage threshold of carbon nanotubes was slightly less than 0.06 mw. This study contributes to the development of nanocomposite preparation methods for laser micromachining.

The objective of this study was to examine the clinical characteristics of patients with different cumulative hemodialysis (HD) durations, so as to improve their survival rate. In this cross-sectional study, we extracted background information and relevant clinical data from 145 patients who were undergoing maintenance HD three times a week at the Affiliated Hospital of Nantong University between January 1998 and January 2019. The study subjects were divided into four groups according to the duration of their HD: <5 years, 5-10 years, 10-15 years, and >15 years of HD. We collected the medical history and relevant clinical parameters for each subject, and measured the urea reduction ratio (URR), hemoglobin (Hb), serum calcium, phosphorus, parathyroid hormone (iPTH), and serum albumin (ALB) levels for each group. The average patient age was 52.06 ±  11.93 years old. The average patient age in the 10-15 years and >15 years groups was significantly lower than in the <5 years and 5-10 years groups (  = 0.002,  < 0.001,  = 0.012, and  = 0.0025, respectively). The most common cause of end-stage renal disease (ESRD) was chronic glomerulonephritis. We found no significant differences in URR, Hb, serum calcium, serum phosphorus, iPTH, and ALB levels. A prolonged HD duration was related to a younger mean age at the start of HD treatment. The leading cause of ESRD was chronic glomerulonephritis. We predominantly found diabetic nephropathy in the group with a duration of <5 years cumulative HD. Most of the indexes related to hemodialysis almost satisfied the recommended values in these patients.

Ischemia-reperfusion (IR) injury often affects transplant and native kidneys alike. IR injury is one of the main causes of acute kidney injury (AKI) and further associated with the progression of chronic kidney disease. Our previous study revealed the renoprotection of erythropoietin derived cyclic helix-B surface peptide (CHBP) against IR injury. However, the precise role and underlying mechanism of endoplasmic reticulum stress (ERS) in the injury and the renoprotection induced by IR or CHBP, respectively, have not been fully defined. This study using mouse kidney epithelial cells (TCMK-1) revealed that the level of CHOP (a key marker of ERS), PERK, and JNK (regulators of CHOP) was gradually increased by the prolonged time of hydrogen peroxide (H O ) stimulation. In addition, CHOP mRNA and protein were significantly reduced by small interfering RNA (siRNA) target CHOP, as were apoptotic and inflammatory mediator caspase-3 and HMGB-1, and early apoptosis. Furthermore, mRNA was correlated positively with PERK protein, active caspase-3, HMGB-1 and apoptosis, but negatively with cell viability , while CHOP protein was also correlated positively with the level of tubulointerstitial damage and active caspase-3 protein . Finally, CHBP improved the viability of TCMK-1 cells subjected to H O stimulation time-dependently, with reduced level of mRNA. CHBP also inhibited the increase of CHOP protein, not only in TCMK-1 cells, but also in the IR injury kidneys at 2 weeks. Moreover, CHBP reduced the expression of mRNA and protein, JNK and HMGB-1 protein, as well as early and later apoptosis. In addition, raised CHOP at 12 h post IR injury might be an early time window for intervention. In conclusion, the differential role of ERS and CHBP in IR-related injury was proved in mouse TCMK-1 cells and kidneys, in which the mechanistic signaling pathway was associated with CHOP/PERK/JNK, HMGB-1/caspase-3, and apoptosis. CHOP might be a potential biomarker and CHBP might be therapeutic drug for IR-induced AKI.

Ischemia reperfusion (IR) and cyclosporine A (CsA) injuries are unavoidable in kidney transplantation and are associated with allograft dysfunction. Herein, the effect and mechanism of a novel tissue protective peptide, helix B surface peptide (HBSP) derived from erythropoietin, were investigated in a rat model. The right kidney was subjected to 45 min ischemia, followed by left nephrectomy and 2-week reperfusion, with or without daily treatment of CsA 25 mg/kg and/or HBSP 8 nmol/kg. Blood urea nitrogen was increased by CsA but decreased by HBSP at 1 week and 2 weeks, while the same changes were revealed in urinary protein/creatinine only at 2 weeks. HBSP also significantly ameliorated tubulointerstitial damage and interstitial fibrosis, which were gradually increased by IR and CsA. In addition, apoptotic cells, infiltrated inflammatory cells, and active caspase-3+ cells were greatly reduced by HBSP in the both IR and IR + CsA groups. The 17 kD active caspase-3 protein was decreased by HBSP in the IR and IR + CsA kidneys, with decreased mRNA only in the IR + CsA kidneys. Taken together, it has been demonstrated, for the first time, that HBSP effectively improved renal function and tissue damage caused by IR and/or CsA, which might be through reducing caspase-3 activation and synthesis, apoptosis, and inflammation.

A nocardial abscess is a relatively rare opportunistic infection that typically occurs after immunosuppressive treatment and is a clinical challenge. In the present study, the case of a 69-year-old patient with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, and lung and kidney involvement, was reported. The patient received systemic glucocorticoid and cyclophosphamide treatment for 6 months, after which a large encapsulated abscess appeared on magnetic resonance imaging and CT in the subcutaneous tissue of the left hip and lung, respectively, and the pus culture showed Nocardia. Orthopedic abscess incision and ultrasound-guided thoracic puncture drainage were performed, and the lesion was completely absorbed after 1 month of treatment with linezolid and compound sulfamethoxazole. Tests for ANCA were negative, and renal function and urine tests were completely normal after 1 year of follow-up. Furthermore, a literature review performed for the present study retrieved a few reports of successful treatment of multiple nocardial abscesses secondary to ANCA-associated vasculitis in elderly patients in a short period of time. Therefore, the present case report and literature review have been reported to improve awareness of this rare disease, so as to facilitate its early diagnosis and treatment.