Metal-organic framework derived crystalline nanocarbon for Fenton-like reaction.

Nanoporous carbons with tailorable nanoscale texture and long-range ordered structure are promising candidates for energy, environmental and catalytic applications, while the current synthetic methods do not allow elaborate control of local structure. Here we report a salt-assisted strategy to obtain crystalline nanocarbon from direct carbonization of metal-organic frameworks (MOFs). The crystalline product maintains a highly ordered two-dimensional (2D) stacking mode and substantially differs from the traditional weakly ordered patterns of nanoporous carbons upon high-temperature pyrolysis. The MOF-derived crystalline nanocarbon (MCC) comes with a high level of nitrogen and oxygen terminating the 2D layers and shows an impressive performance as a carbocatalyst in Fenton-like reaction for water purification. The successful preparation of MCC illustrates the possibility to discover other crystalline heteroatom-doped carbon phases starting from correctly designed organic precursors and appropriate templating reactions.

Retrospective study of 189 cases of acute perforated peptic ulcer: safety and efficacy of over-the-scope-clip based endoscopic closure.

BACKGROUND: To compare the clinical outcomes in patients with acute perforated peptic ulcer (PPU) treated with over-the-scope clip (OTSC), non-surgical, and surgical interventions, and to explore the effectiveness and safety of OTSC closure. METHODS: Hospital stay, antibiotic use, diet resumption time, and mortality rate were analyzed retrospectively. Binary Logistic regression analysis was used to identify the risk factors influencing PPU complicated with sepsis. RESULTS: Patients were divided into three treatment groups: OTSC (n = 62), non-surgical (n = 72), and surgical (n = 55) groups. The median time (IQR) from symptom onset to admission was 9.0 (4-23) h. 88.71% (55/62) of the patients in In the OTSC group underwent OTSC closure within 24 h (median [IQR] time: 14.5 [7.00-30.25] h). The perforation diameters in the OTSC and surgical groups were 9.87 mm ± 5.97 mm and 8.55 mm ± 6.17 mm, respectively. The median (IQR) hospital stays in the OTSC (9.50 [7.00-12.25] days) and non-surgical group (9.00[7.00-13.00]days) were similar (p > 0.05), but shorter than that in surgical group (12.00[10.00-16.00]days), (p < 0.05). The median duration of antibiotic use was shorter in the OTSC group (7.00[3.00-10.00]) than in the non-surgical group (9.00[7.00-11.00]) and surgical group (11.00[9.00-13.00]) ( p < 0.05); and the time to resume oral feeding was shorter in the OTSC group (4.00[2.00-5.25]) than in the non-surgical group (7.00[6.13-9.00]) and surgical group (8.00[6.53-10.00]), respectively ( p < 0.05). No mortality difference among groups (p = 0.109) was found. Lower albumin level at admission, older age, and elevated creatinine levels were associated with increased sepsis risk, with OR(95%CI) of 0.826 (0.687-0.993), 1.077 (1.005-1.154), and 1.025 (1.006-1.043), respectively (all p < 0.05). CONCLUSION: OTSC closure improves clinical outcomes of acute PPU patients without sepsis. Age, hypoalbuminemia, and baseline renal dysfunction increase the risk of sepsis, while mortality was associated with sepsis and multiorgan dysfunction.

Construction of a physiologically based pharmacokinetic model of paclobutrazol and exposure estimation in the human body.

Paclobutrazol (PBZ) is a plant growth regulator that can delay plant growth and improve plant resistance and yield. Although it has been widely used in the growth of medicinal plants, human beings may take it by taking traditional Chinese medicine. There are no published studies on PBZ exposure in humans or standardized limits for PBZ in medicinal plants. We measured the solubility, oil-water partition coefficient (logP), and pharmacokinetics of PBZ in rats and established a physiologically based pharmacokinetic (PBPK) model of PBZ in rats. This was followed by extrapolation to healthy Chinese adult males as a theoretical foundation for future risk assessment of PBZ. The results showed that PBZ had low solubility and high fat solubility. Pharmacokinetic experiments showed that PBZ was absorbed rapidly but eliminated slowly in rats. On this basis, the rat PBPK model was successfully constructed and extrapolated to healthy Chinese adult males to predict the plasma concentration-time curve and exposure of PBZ in humans. The construction of the PBPK model of PBZ in this study facilitates the determination of the standard formulation limits and risk assessment of PBZ residues in medicinal plants.

TLR9 promotes monocytic myeloid-derived suppressor cell induction during JEV infection.

Myeloid-derived suppressor cells (MDSCs) are a group of heterologous populations of immature bone marrow cells consisting of progenitor cells of macrophages, dendritic cells and granulocytes. Recent studies have revealed that the accumulation of MDSCs in the mouse spleen plays a pivotal role in suppressing the immune response following JEV infection. However, the mechanisms by which JEV induces MDSCs are poorly understood. Here, it was found that JEV infection induces mitochondrial damage and the release of mitochondrial DNA (mtDNA), which further leads to the activation of TLR9. TLR9 deficiency decreases the M-MDSCs population and their suppressive function both in vitro and in vivo. Moreover, the increase of MHCⅡ expression on antigen-presenting cells and CD28 expression on T cells in TLR9-/- mice was positively correlated with M-MDSCs reduction. Accordingly, the survival rate of TLR9-/- mice dramatically increased after JEV infection. These findings reveal the connections of mitochondrial damage and TLR9 activation to the induction of M-MDSCs during JEV infection.

Studies of Mycotoxins in Medicinal Plants Conducted Worldwide over the Last Decade: A Systematic Review, Meta-Analysis, and Exposure Risk Assessment.

BACKGROUND: Mycotoxins have been reported to be present in medicinal plants. With the growing usage of medicinal plants, contamination of mycotoxins has emerged as one of the biggest threats to global food hygiene and ecological environment, posing a severe threat to human health. PURPOSE: This study aimed to determine the mycotoxin prevalence and levels in medicinal plants and conduct a risk assessment by conducting a systematic review and meta-analysis. METHODS: A thorough search on Web of Science and PubMed was conducted for the last decade, resulting in 54 studies (meeting the inclusion criteria) with 2829 data items that were included in the meta-analysis. RESULTS: The combined prevalence of mycotoxins in medicinal plants was 1.7% (95% confidence interval, CI = 1.1% - 2.4%), with a mean mycotoxin concentration in medicinal plants of 3.551 µg/kg (95% CI = 3.461 - 3.641 µg/kg). Risk assessment results indicated that aflatoxins and ochratoxin A found in several medicinal plants posed a health risk to humans; additionally, emerging enniatins exhibited possible health risks. CONCLUSION: Therefore, the study underlines the need for establishing stringent control measures to reduce the severity of mycotoxin contamination in medicinal plants.

Advances in the endoscopic management of gastric varices.

This review provides an overview of the treatment options available for gastric varices (GV) with a focus on endoscopic methods. Various minimally invasive techniques, including endoscopic band ligation, endoscopic cyanoacrylate injection, and transjugular intrahepatic portosystemic shunt, can be applied to the treatment of GV. Endoscopic cyanoacrylate injection is now recognized as a first-line treatment for GV. Endoscopic ultrasound-guided cyanoacrylate injection combined with coils has shown good security and effectiveness. Thrombin injection therapy is a promising treatment, with a similar hemostasis rate to cyanoacrylate injection but with fewer serious complications. With the deepening understanding of the hemodynamics of the GV system, various treatment methods and their combination are gradually evaluated to provide patients with safer and more effective treatment options.

Dendritic Cell-Derived Exosomes Stimulated by Treponema pallidum Induce Endothelial Cell Inflammatory Response through the TLR4/MyD88/NF-κB Signaling Pathway.

Exosomes have been implicated in vascular damage in recent research. The influence of dendritic cell-derived exosomes generated by Treponema pallidum (T. pallidum) on the inflammatory process of vascular cells was examined in this study. Human umbilical vein endothelial cells (HUVECs) were cocultured with exosomes isolated from dendritic cells induced by T. pallidum. Western blot and reverse transcription-quantitative real-time polymerase chain reaction were used to assess toll-like receptor 4 (TLR4) expression and the quantity of proinflammatory cytokines. The findings showed that the expression of TLR4 was considerably upregulated, and TLR4 knockdown dramatically reduced interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) production in exosome-treated HUVECs. Furthermore, TLR4 silencing reduced myeloid differentiation primary response protein 88 (MyD88) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB) levels in exosome-treated HUVECs. Additionally, suppression of the activity of NF-κB with BAY11-7082, an NF-κB inhibitor, also reduced the exosome-treated inflammatory response. Our results suggested that dendritic cell-derived exosomes stimulated by T. pallidum induced endothelial cell inflammation, and the TLR4/MyD88/NF-κB signal axis was activated, significantly increasing IL-1ß, IL-6, and TNF-α expression. This may have a significant role in the vascular inflammatory response in syphilis, which would contribute to the understanding of the pathogenesis of syphilis and the host immunological response to T. pallidum.

Plasma Exosome-Derived microRNAs Profiles in Patients with Serofast Status: A Cross-Sectional Study.

Purpose: Syphilis is a sexually transmitted bacterial infection caused by Treponema pallidum (T. pallidum), which can lead to chronic morbidity and adverse complications. In clinical practice, serofast status (SF) patients present with clinical symptoms that are very similar to those of healthy individuals or syphilis-cured patients, and often require prolonged follow-up for diagnosis. Currently, there is increasing interest in the potential of plasma exosome-derived miRNA as a biomarker for the detection of infectious diseases. In this study, we aimed to explore the diagnostic potential of miRNA in SF and its possible biological implications. Patients and Methods: Exosome-derived miRNAs were isolated from peripheral plasma samples obtained from 20 patients with secondary syphilis (SS), SF, serologically cured syphilis (SC), and healthy controls (HC), and differentially expressed miRNAs (DEmiRNAs) were identified by microarray analysis. Prediction of potential target genes, functional annotation, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were then performed. The expression of selected miRNAs was confirmed in 37 patients by quantitative reverse transcription polymerase chain reaction (RT-qPCR). A receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance of these miRNAs in differentiating syphilis from HC or SC. Results: The expression profile of plasma exosome-derived miRNA was discovered in individuals with SF through microarray analysis. The targeted genes of DEmiRNAs were found to be involved in diverse biological processes according to GO and KEGG analysis, such as regulation of transcription, mitochondria, Golgi, immune system, apoptosis, Ras signaling pathway, etc. Using RT-qPCR validation, miR-1273g-3p, miR-4485-5p, miR-197-3p, and miR-1908-3p showed significant upregulation in patients with SF. These miRNAs exhibited a superior diagnostic ability, either individually or combined, to distinguish SF from SC or HC. Conclusion: The DEmiRNAs in plasma exosomes may play a role in the pathogenesis of SF and have the potential to become a noble and effective diagnostic method.

Elevated Pro-inflammatory Cytokine Levels in Acute Reflux Esophagitis Are Reduced by 1,25 Dihydroxy Vitamin D3.

BACKGROUND/AIM: Gastric acid reflux into the esophagus can cause irritation and inflammation of the esophagus and progress to reflux esophagitis (RE). Vitamin D3 (VitD3) has anti-inflammatory effects and plays an important regulatory role in adaptive and innate immunity. We hypothesized that VitD3 may play a protective role in RE. MATERIALS AND METHODS: Seventy male Sprague-Dawley rats were used, and acute RE (n=35) or chronic RE (n=35) were surgically induced. The effects of different doses of VitD3 on morphological changes and alteration of pro-inflammatory cytokine levels were examined in the rat models. Western blot analysis was performed to determine protein expression levels of IL-1ß, IL-6, and IL-8 in esophageal tissues. Serum levels of VitD3 and calcium were determined using enzyme-linked immunosorbent assays. RESULTS: The protein expression of pro-inflammatory cytokines IL-1ß, IL-6, and IL-8 was found significantly increased in RE. VitD3 treatment significantly reduced the levels of these pro-inflammatory cytokines in both the low-dose and high-dose VitD3 groups compared to control groups in acute RE, but not chronic RE. Macrographic and histopathological examination revealed various degrees of esophageal impairment in rats following surgical induction of acute or chronic RE in rats. These impairments were not improved by VitD3. Morphological grading of esophageal mucosa showed no significant differences between acute and chronic RE. Elevated serum levels of calcium were observed after VitD3 treatment. CONCLUSION: IL-1ß, IL-6, and IL-8 levels were significantly elevated in RE. The abnormal increase in these important pro-inflammatory cytokines was suppressed by VitD3 in the rat models of acute RE. These novel findings suggest a potential protective role of VitD3 in early-stage RE.

The Role of Tyrosine Kinase Inhibitors in Reduction of Mortality from Non-small Cell Lung Cancer: A Meta-analysis.

BACKGROUND: Tyrosine kinase inhibitors are widely used in the treatment of non-small cell lung cancer. However, the exact role of these inhibitors, particularly in the reduction of mortality of non-small cell lung cancer, is unclear so far. As a result, we used RevMan 5 to conduct a meta- analysis of accessible data from randomised clinical trials. METHODS: The studies were categorised based on the inclusion and exclusion criteria after being collected from PubMed using appropriate MeSH terms. The fixed or random effect model was used based on heterogeneity among studies. The overall estimate was estimated as an odd ratio with a confidence interval of 95%. The heterogeneity among studies was calculated by I2 and Cochrane Q test. The qualitative analysis of publication bias was done using a funnel plot. RESULTS: The overall estimate measures [OR 1.02 (0.83, 1.25)] have shown non-significant role of tyrosine kinase inhibitors in reduction of deaths of non-small cell lung cancer patients as compared to non-tyrosine kinase inhibitors group. The subgroup analysis of individual tyrosine kinase inhibitors (erlotinib, gefitinib, afatinib, osimertinib and vandetanib) has also shown similar findings. CONCLUSION: Based on available data, there is no significant role played by tyrosine kinase inhibitors in the reduction of deaths of non-small cell lung cancer patients.

'Green-to-Green': Iron oxides embedded in lignin-based carbon scaffolds for water remediation via oxidation excluding free-radical pathways.

Advanced oxidation processes (AOP) are a common tool to remove organic compounds from the water cycle. The process is mostly relied on free radicals (i.e., SO4•- and HO•) with high oxidation power in solution. Surface-mediated mechanism could improve this process to prevent undesired quenching of aqueous radicals that widely exists in free radical pathways and alleviate metal leaching through direct electron transfer. In this work, a facile low-temperature pre-treatment combined with pyrolytic strategy was employed to construct a green catalyst with iron oxides embedded in Kraft-lignin derived bio-char (γ-Fe2O3 @KC), upon which radicals stay surface mediated and the activity-stability trade-off is achieved for pollutant degradation. The γ-Fe2O3 @KC is capable of activating PMS to generate non-radical species which are more stable (1O2 and Fe(V)=O) and of enhancing electron transfer efficiency. A surface-bound reactive complex (Catalyst-PMS*) was identified by electrochemical characterization and was discussed with primary surface-bound radical pairs to explain the contradictions between quenching and EPR detection results. We analyzed the γ-Fe2O3 @KC as a PMS-activating catalyst for a wider range of oxidation targets, such as Rhodamine B (∼100%), p-nitrophenol (∼85%), and Ciprofloxacin (∼63%), and found competitive removal efficiencies. The system also shows an encouraging reusability for at least 5 times and high stability at pH 3-9, and the low concentration of iron in γ-Fe2O3 @KC/PMS system implies the carbon scaffold of biochar alleviate the leakage process. The combined findings highlight the applicability in 'green (source) to green (application)' processes using cost-effective and bio-friendly iron@carbon catalysts, where alternative oxidation pathways are activated to play a dominant role for water purification.

N-3 polyunsaturated fatty acids protect esophageal epithelial cells from acid exposure.

Our previous study showed that n-3 PUFAs inhibited inflammation in rats with esophagitis. This study aimed to observe the protective effect of n-3 PUFAs against acid damage to esophageal epithelial cells (Het-1A cells) and to explore its mechanism. The level of malondialdehyde (MDA) was increased by acid exposure, while that of superoxide dismutase (SOD) was decreased. In groups with different ratios of n-6/n-3 PUFAs, the expression levels of nuclear factor E2 related factor 2 (Nrf2) and SOD were increased with increasing proportions of n-3 PUFAs and were highest in the 1:1 group. Compared with those in the 9:1 group, the expression of NOD like receptor pyrin domain-containing protein 3 (NLRP3) and caspase-1 and the pyroptosis rate in the 1:1 group were decreased. Intervention with an Nrf2 agonist increased the expression of Nrf2 and decreased the expression of NLRP3 and caspase-1 and the pyroptosis rate. However, inhibiting Nrf2 expression led to the opposite result. In conclusion, n-3 PUFAs protected esophageal epithelial cells from acid damage by upregulating Nrf2 expression, which disrupted oxidative stress and NLRP3 inflammasome activation and inhibited pyroptosis.

Thermal property evaluation of a 2.5D integration method with device level microchannel direct cooling for a high-power GaN HEMT device.

Gallium nitride high electron mobility transistor (GaN HEMT) devices have become critical components in the manufacturing of high-performance radio frequency (RF) or power electronic modules due to their superior characteristics, such as high electron saturation speeds and high power densities. However, the high heat characteristics of GaN HEMTs make device level cooling a critical problem to solve since performance degradation or even failure may occur under high temperatures. In this paper, we proposed a 2.5D integration method with device-level microchannel direct cooling for a high-power GaN HEMT device. To demonstrate this technological concept, a multigate GaN HEMT device featuring a gate length/width/source drain spacing of 0.5 µm/300 µm/6 µm that underwent in-house backside thinning and metallization was used as the test vehicle. A high-resistivity silicon (HR Si) interposer embedded with four-layer microchannels was designed, having widths/pitches of 30 µm/30 µm at the top microchannel. The high-power GaN HEMT device was soldered on a Si interposer embedded with open microchannels for heat dissipation. A pair of GSG Pad chips was soldered simultaneously to display the capacity for the heterogeneous integration of other chip types. Thermal property evaluation was conducted with experiments and simulations. The test results showed that the maximum surface temperature of the GaN HEMT device decreased to 93.8 °C when it experienced a heat dissipation density of 32 kW/cm2 in the gate finger area and an average heat dissipation density of 5 kW/cm2 was found in the active area with the DI water coolant at a flow rate of 3 mL/min. To our knowledge, among recently reported works, this finding was the best cooling capacity of heterogeneously integrated microchannels for GaN HEMT devices. In addition, this technology was scalable regarding the numbers of gate fingers or GaN HEMT devices.

Lamellar carbon nitride membrane for enhanced ion sieving and water desalination.

Membrane-based water treatment processes offer possibility to alleviate the water scarcity dilemma in energy-efficient and sustainable ways, this has been exemplified in filtration membranes assembled from two-dimensional (2D) materials for water desalination purposes. Most representatives however tend to swell or disintegrate in a hydrated state, making precise ionic or molecular sieving a tough challenge. Here we report that the chemically robust 2D carbon nitride can be activated using aluminum polycations as pillars to modulate the interlayer spacing of the conjugated framework, the noncovalent interaction concomitantly affords a well-interlinked lamellar structure, to be carefully distinguished from random stacking patterns in conventional carbon nitride membranes. The conformally packed membrane is characterized by adaptive subnanochannel and structure integrity to allow excellent swelling resistance, and breaks permeability-selectivity trade-off limit in forward osmosis due to progressively regulated transport passage, achieving high salt rejection (>99.5%) and water flux (6 L m-2 h-1), along with tunable permeation behavior that enables water gating in acidic and alkaline environments. These findings position carbon nitride a rising building block to functionally expand the 2D membrane library for applications in water desalination and purification scenarios.

Full-length TprK of Treponema pallidum subsp. pallidum in lipid nanodiscs is a monomeric porin.

TprK is a key virulence factor of Treponema pallidum subsp. pallidum (T. pallidum) due to its ability to undergo intra-strain antigenic variation through gene conversion. This mechanism can generate millions of tprK gene and protein variants to allow immune evasion and pathogen persistence during infection. In silico structural modeling supports that TprK is an outer membrane ß-barrel with porin function and with several surface-exposed loops, seven of which corresponding to the variable regions. No definitive structural of functional data, however, exist for this protein aside from its role in immune evasion. Studies to elucidate TprK biological function as a porin, are hindered by the evidence that TprK is not abundant on T. pallidum outer membrane, and by the fragility of T. pallidum envelope. To gain insight onto TprK structure and possible function as a porin, we used an Escherichia coli - based expression system that yielded highly pure full-length TprK without any intermediate denaturation step, and proceeded to reconstitute it in detergents and lipid nanodiscs. Visualization of TprK in nanodiscs using negative staining electron microscopy supported that TprK is a monomeric porin in an artificial lipid environment mimicking T. pallidum membrane. Our work provided evidence that TprK is a possible porin transporter of T. pallidum, a biological function compatible with its structural models. These results bring us closer to a comprehensive understanding of the function of this important virulence factor in syphilis pathogenesis and T. pallidum biology.

Effect of Endoscopic Appendix Intubation and Irrigation on Acute Uncomplicated Appendicitis.

OBJECTIVE: To investigate the efficacy and safety of endoscopic appendix intubation and irrigation (EAI) on acute uncomplicated appendicitis. METHODS: This prospective non-randomized study examined 169 patients with suspected acute uncomplicated appendicitis at The First Affiliated Hospital of Fujian Medical University from October 2015 to 2017. Patients were divided into three groups: endoscopic appendix intubation and irrigation (EAI, n = 18), laparoscopic appendectomy (LA, n = 87), and antibiotic alone (A, n = 64). The treatment success rate, duration of hospitalization, medical costs, operation time, duration of abdominal pain, fasting time, complications, and recurrence were analyzed. RESULTS: The three groups had no significant differences in baseline characteristics (age, gender, Alvarado score, white blood cell count, and neutrophil count; all P > 0.05). Compared to the LA group, the EAI group had shorter durations of the operation, fasting, and abdominal pain; less use of oral and intravenous antibiotics; and lower medical costs (all P < 0.05). Compared to the A group, the EAI group had shorter durations of abdominal pain and hospitalization, and less use of intravenous antibiotics (all P < 0.05). The EAI group had no complications, but 3 patients (3.4%) in the LA group had surgery-related complications. CONCLUSION: EAI is a safe and effective treatment for acute uncomplicated appendicitis. Patients who received EAI had shorter durations of abdominal pain and hospitalization than those who received LA or conservative antibiotic treatment. TRIAL REGISTRATION NUMBER AND AGENCY: ChiCTR-IPN-15006565, Chinese Clinical Trial Registry.

The Parameters Identification of High-Temperature Constitutive Model Based on Inverse Optimization Method and 3D Processing Map of Cr8 Alloy Steel.

As a novel kind of cold roller steel, Cr8 alloy steel has the characteristics of high hardness, high wear resistance and good toughness, which can effectively prolong the service life of the roller that is an important part of the steel rolling mill. How to accurately define the constitutive model parameters of metal materials is the major problem, because it seriously affects the accuracy of numerical simulation results of the roller hot forming process. In the study of Cr8 alloy steel's thermal deformation behavior of the present paper, the high temperature compression test was done on a Gleebel-1500D thermal/force simulation testing machine. A novel method of parameter identification was proposed based on inverse optimization. The Hansel-Spittel constitutive model was established by using the inverse optimization method. To carry out the verification on the accuracy of the established constitutive model, the predicted flow-stress of constitutive model was made a contrast to the experimental flow-stress, and the standard statistical parameters were also applied to further evaluation. The results showed a relatively high prediction accuracy of the Hansel-Spittel constitutive model based on the inverse optimization algorithm. Meanwhile, to obtain optimal parameters of Cr8 alloy steel in the thermal processing, 3D thermal processing maps concerning strain-rate, strain and temperature were built based on the dynamic material model. According to the 3D processing map, the most adequate thermal processing parameters of Cr8 alloy steel were obtianed as follows: strain 0.2-0.4, strain-rate 0.05-0.005 s-1, temperature 1100-1150 °C.

Identification of the Constitutive Model Parameters by Inverse Optimization Method and Characterization of Hot Deformation Behavior for Ultra-Supercritical Rotor Steel.

X12 (X12CrMoWVNbN10-1-1) ferritic heat resistant steel is an important material for the production of new-generation ultra-supercritical generator rotors. Hot compression tests of X12 ferritic heat-resistant steel were performed via a Gleeble-1500D testing machine under temperatures of 1050-1250 °C and strain rates of 0.05-5 s-1. In order to provide material model data for finite element simulations and accurately predict the hot deformation behavior, a reverse optimization method was proposed to construct elevated temperature constitutive models of X12 ferritic heat-resistant steel in this paper, according to the Hansel-Spittel constitutive model. To verify the accuracy of the model, the predicted and experimental values of the constitutive model were compared. The results indicated that the model had a high prediction accuracy. Meanwhile, the correlation coefficient between the experimental value and the predicted value of constitutive model was 0.97833. For further verification of the accuracy of the model, it was implemented in finite element FORGE@ software to simulate the compression tests of different samples under different conditions. Comparing actual displacement-load curves with displacement-load curves acquired through finite element simulations, the results indicated that displacement-load curves predicted by the model were very consistent with actual displacement-load curves, which verified the accuracy of the model. Moreover, to research the optimal processing parameters of the material, hot processing maps were drawn according to the dynamic material model. In terms of microstructure evolution, a characteristic area distribution map of the hot processing map was established. Therefore, the optimal hot forming parameters regions were in the range of 1150-1200 °C/0.05-0.62 s-1 for X12 ferritic heat-resistant steel.

Design and Mechanical Compatibility of Nylon Bionic Cancellous Bone Fabricated by Selective Laser Sintering.

In order to avoid the stress shielding phenomenon in orthopedic bionic bone implantation, it is necessary to consider the design of mechanical compatible implants imitating the host bone. In this study, we developed a novel cancellous bone structure design method aimed at ensuring the mechanical compatibility between the bionic bone and human bone by means of computer-aided design (CAD) and finite element analysis technology (specifically, finite element modeling (FEM)). An orthogonal lattice model with volume porosity between 59% and 96% was developed by means of CAD. The effective equivalent elastic modulus of a honeycomb structure with square holes was studied by FEM simulation. With the purpose of verifying the validity of the cancellous bone structure design method, the honeycomb structure was fabricated by selective laser sintering (SLS) and the actual equivalent elastic modulus of the honeycomb structure was measured with a uniaxial compression test. The experimental results were compared with the FEM values and the predicted values. The results showed that the stiffness values of the designed structures were within the acceptable range of human cancellous bone of 50-500 MPa, which was similar to the stiffness values of human vertebrae L1 and L5. From the point of view of mechanical strength, the established cellular model can effectively match the elastic modulus of human vertebrae cancellous bone. The functional relationship between the volume porosity of the nylon square-pore honeycomb structure ranging from 59% to 96% and the effective elastic modulus was established. The effect of structural changes related to the manufacture of honeycomb structures on the equivalent elastic modulus of honeycomb structures was studied quantitatively by finite element modeling.

Skin autofluorescence and the complexity of complications in patients with type 2 diabetes mellitus: a cross-sectional study.

BACKGROUND: The accumulation of advanced glycation end products (AGEs) occurring in skin tissues can be measured as skin autofluorescence (SAF). Here, we assessed the correlation between SAF values and the complexity and severity of type 2 diabetes mellitus (T2DM) complications. METHODS: The basic clinical information of 825 patients with T2DM was collected through an electronic system, and SAF was measured by adapting a DM-Scan, a non-invasive optical signal detector. Diabetic complications were diagnosed based on clinical criteria by experienced doctors. Linear regression analysis was used to evaluate the independent determinants of SAF, and multiple logistic regression analysis was performed to assess independent determinants that influence the severity of the complications. RESULTS: SAF was significantly associated with the complexity of T2DM complications. Similarly, independent relationships between SAF and age (ß = 0.389, P <  0.001), sex (ß = - 2.221, P = 0.004), 2-h C-peptide (ß = - 0.182, P = 0.017), aminotransferase (ALT, ß = - 0.158, P = 0.041), blood creatinine (BCr, ß = 0.206, P = 0.009), and fatty liver (ß = 0.161, P = 0.026) were observed. With the increasing number of complications, the SAF values increased significantly after adjusting for related risk factors. The SAF values correlated with diabetic retinopathy, diabetic kidney diseases, cardiovascular disease, and diabetic peripheral neuropathy when compared with patients without any T2DM-associated complications. Moreover, the AGE-based diabetic complication risk score for each complication demonstrated a relationship with the presence or absence of certain complications. CONCLUSION: SAF is an independent marker for diabetic retinopathy, diabetic kidney diseases, cardiovascular disease, and diabetic peripheral neuropathy, and it is also a predictor of the complexity of T2DM complications. Moreover, the diabetic complication risk score is capable of predicting the risk of diabetic complications in patients with T2DM.