A multiline fitting method for measuring ethylene concentration based on WMS-2f/1f

Coal spontaneous combustion risk assessment is a global technical challenge for the sustainable development of deep mining technology, and C2H4 is a key indicator for early warning of coal spontaneous combustion. Tunable diode laser absorption spectroscopy (TDLAS) has the advantages of high selectivity, high sensitivity, high accuracy and real-time on-line measurement, and it can detect multiple gases simultaneously, so it has significant advantages in the accurate detection of coal spontaneous combustion indicator gases. To address the problem of cross-interference between the near-infrared absorption lines of CH4 and C2H4, which are the indicator gases of spontaneous combustion in coal, a multi-line fitting method was proposed in this study to calibrate the concentration of C2H4. The high-precision Environics2000 automatic standard gas dispenser from the United States, which has a built-in CPU computer control and data control and processing system, was used. Its gas concentration accuracy: ± 1.0%, gas flow accuracy: ± 1.0%, gas repeatability accuracy: ± 1.0%, flow linearity accuracy: ± 0.5%, and inlet operating pressure: minimum 10 psig (0.67 bar) ~ 75 psig (5.04 bar). The measured and simulated WMS-2f/1f signals were multilinearly fitted using a multilinear fitting algorithm and wavelength modulation spectroscopy (WMS), and the measurement of C2H4 concentration was achieved based on the extracted spectral line information. The results show that the maximum relative error of C2H4 concentration measurement is 2.40%, which is 54% lower than that of the conventional 2f peak measurement method, thus demonstrating the effectiveness of the multilinear fitting algorithm in the inversion of C2H4 concentration under the interference of absorption lines. In addition, this study has far-reaching implications for the application of TDLAS technology in the accurate detection of coal spontaneous combustion indicator gases.

Herbicide residues in soil decrease microbe-mediated plant protection

The residues of glyphosate are found to remain in soils longer than previously reported, affecting rhizosphere microbes. This may adversely affect crop and other non-target plants because the plant's resilience and resistance largely rely on plant-associated microbes. Ubiquitous glyphosate residues in soil and how they impact mutualistic microbes inhabiting the aboveground plant parts are largely unexplored. We studied the effects of herbicide residues in soil on Epichloë sp., which are common endophytic symbionts inhabiting aerial parts of cool-season grasses. In this symbiosis, the obligate symbiont subsists entirely on its host plant, and in exchange, it provides alkaloids conferring resistance to herbivores for the host grass that invests little in its own chemical defence. We first show decreased growth of Epichloë endophytes in vitro when directly exposed to two concentrations of glyphosate or glyphosate-based herbicides. Second, we provide evidence for a reduction of Epichloë-derived, insect-toxic loline alkaloids in endophyte-symbiotic meadow fescue (F. pratensis) plants growing in soil with a glyphosate history. Plants were grown for 2 years in an open field site, and natural herbivore infestation was correlated with the glyphosate-mediated reduction of loline alkaloid concentrations. Our findings indicate that herbicides residing in soil not only affect rhizosphere microbiota but also aerial plant endophyte functionality, which emphasizes the destructive effects of glyphosate on plant symbiotic microbes, here with cascading effects on plant-pest insect interactions.

Thermodynamic Analysis of In Situ Underground Pyrolysis of Tar-Rich Coal: Primary Reactions

In situ underground pyrolysis of tar-rich coal is significant for alleviating the scarcity of oil and gas resources and realizing the green and efficient development and utilization of coal in China. Tar-rich coal is often subjected to high axial pressure, surrounding pressure, and pore pressure in the in situ underground pyrolysis environment. Consequently, laboratory simulation conditions are difficult to meet the actual needs. This paper conducts a thermodynamic study of the pyrolysis characteristics of tar-rich coal under an in situ environment. Typical thermodynamic functions of tar-rich coal, including the standard enthalpy of formation, standard formation Gibbs free energy, and standard entropy, were determined. Ten representative primary reactions were constructed with typical tar-rich coal pyrolysis oil components as a guide. The Gibbs free energy and equilibrium constant change laws of the above reactions were analyzed for pyrolysis temperatures from 200 to 800 °C and pyrolysis pressures from atmospheric pressure to 10 MPa. The results showed that the standard enthalpy of formation of tar-rich coal was -72.27 kJ·mol^-1, the standard entropy was -37.79 J·mol^-1·K^-1, and the standard formation Gibbs free energy was -60.01 kJ·mol^-1. When the reaction pressure increased from atmospheric pressure to 10 MPa, the thermodynamically feasible initial temperature fractions of the primary reaction of tar-rich coal pyrolysis all showed different degrees of increase. In the underground environment, the initial temperature of the primary reaction of in situ underground pyrolysis of tar-rich coal moves to a higher-temperature gradient to some extent, so the adjustment of the reaction temperature and pressure could guide the directional regulation of the in situ underground pyrolysis products of tar-rich coal.

[Outcome of surgical repair for aortic coarctation with coexisting descending aortic aneurysm in adult patients]

Objective: To evaluate the efficacy of surgical treatment of aortic coarctation combined with descending aortic aneurysm in adult patients. Methods: This is a retrospective cohort study. Adult patients with aortic coarctation who were hospitalized in Beijing Anzhen Hospital from January 2015 to April 2019 were enrolled. The aortic coarctation was diagnosed by aortic CT angiography, and the included patients were divided into the combined descending aortic aneurysm group and the uncomplicated descending aortic aneurysm group based on descending aortic diameter. General clinical data and surgery-related data were collected from the included patients, and death and complications were recorded at 30 days after surgery, and upper limb systolic blood pressure was measured in all patients at discharge. Patients were followed up after discharge by outpatient visit or telephone call for their survival and the occurrence of repeat interventions and adverse events, which included death, cerebrovascular events, transient ischemic attack, myocardial infarction, hypertension, postoperative restenosis, and other cardiovascular-related interventions. Results: A total of 107 patients with aortic coarctation aged (34.1±15.2) years were included, and 68 (63.6%) were males. There were 16 cases in the combined descending aortic aneurysm group and 91 cases in the uncomplicated descending aortic aneurysm group. In the combined descending aortic aneurysm group, 6 cases (6/16) underwent artificial vessel bypass, 4 cases (4/16) underwent thoracic aortic artificial vessel replacement, 4 cases (4/16) underwent aortic arch replacement+elephant trunk procedure, and 2 cases (2/16) underwent thoracic endovascular aneurysm repair. There was no statistically significant difference between the two groups in the choice of surgical approach (all P>0.05). In the combined descending aortic aneurysm group at 30 days after surgery, one case underwent re-thoracotomy surgery, one case developed incomplete paraplegia of the lower extremity, and one case died; and the differences in the incidence of endpoint events at 30 days after surgery were similar between the two groups (P>0.05). Systolic blood pressure in the upper extremity at discharge was significantly lower in both groups compared with the preoperative period (in the combined descending aortic aneurysm group: (127.3±16.3) mmHg vs. (140.9±16.3) mmHg, P=0.030, 1 mmHg=0.133 kPa; in the uncomplicated descending aortic aneurysm group: (120.7±13.2) mmHg vs. (151.8±26.3) mmHg, P=0.001). The follow-up time was 3.5 (3.1, 4.4) years. There were no new deaths in the combined descending aortic aneurysm group, no transient ischemic attack, myocardial infarction or re-thoracotomy surgery, and one patient (1/15) suffered cerebral infarction and 10 patients (10/15) were diagnosed with hypertension. The differences in the occurrence of endpoint events during postoperative follow-up were similar between the two groups (P>0.05). Conclusion: In experienced centers, long-term prognosis of patients with aortic coarctation combined with descending aortic aneurysm is satisfactory post surgical intervention.

Effect of ripening temperature on the chemical composition of lingonberries (Vaccinium vitis-idaea L.) of northern and southern origin

Lingonberries (Vaccinium vitis-idaea L.) from two locations, northern (69°N, 18°E) and southern (59°N, 10°E) Norway, were grown under controlled conditions in a phytotron at two temperatures (9 and 15 °C) to study the effects of the ripening temperature and origin on the chemical composition of the berries. The concentrations of phenolic compounds, sugars, and organic acids as well as the profile of volatile organic compounds (VOCs) were determined using chromatographic and mass spectrometric methods. Five anthocyanins, eleven flavonols, eight cinnamic acid derivatives, three flavan-3-ols, three sugars, three organic acids, and 77 VOCs were identified, of which 40 VOCs had not previously been reported in lingonberries. Berries from both locations, were found to have higher contents of anthocyanins and cinnamic acid derivatives when ripened at lower temperature (9 °C), compared to the higher temperature (15 °C). Lingonberries of northern origin had a different VOC profile and higher contents of anthocyanins and organic acids than berries originating from the south. Lingonberries from the northern location also had higher proportions of cyanidin-3-O-glucoside and cyanidin-3-O-arabinoside than lingonberries from the southern location. The results show that the composition of lingonberries is influenced by both the environment and the origin of the plants, with phenolic compounds mainly influenced by the growth temperature and VOCs mainly influenced by plant origin.

Clinical Relevance of Plaque Distribution for Basilar Artery Stenosis

BACKGROUND AND PURPOSE

There is no clear association between plaque distribution and postoperative complications in patients with basilar artery atherosclerotic stenosis. The aim of this study was to determine whether plaque distribution and postoperative complications after endovascular treatment for basilar artery stenosis are related.

MATERIALS AND METHODS

Our study enrolled patients with severe basilar artery stenosis who were scanned with high-resolution MR imaging and followed by DSA before the intervention. According to high-resolution MR imaging, plaques can be classified as ventral, lateral, dorsal, or involved in 2 quadrants. Plaques affecting the proximal, distal, or junctional segments of the basilar artery were classified according to DSA. An experienced independent team assessed ischemic events after the intervention using MR imaging. Further analysis was conducted to determine the relationship between plaque distribution and postoperative complications.

RESULTS

A total of 140 eligible patients were included in the study, with a postoperative complication rate of 11.4%. These patients were an average age of 61.9 (SD, 7.7) years. Dorsal wall plaques accounted for 34.3% of all plaques, and plaques distal to the anterior-inferior cerebellar artery accounted for 60.7%. Postoperative complications of endovascular treatment were associated with plaques located at the lateral wall (OR = 4.00; 95% CI, 1.21-13.23; P = .023), junctional segment (OR = 8.75; 95% CI, 1.16-66.22; P = .036), and plaque burden (OR = 1.03; 95% CI, 1.01-1.06; P = .042).

CONCLUSIONS

Plaques with a large burden located at the junctional segment and lateral wall of the basilar artery may increase the likelihood of postoperative complications following endovascular therapy. A larger sample size is needed for future studies.

Thermodynamic Analysis on In Situ Underground Pyrolysis of Tar-Rich Coal: Secondary Reactions

To develop the in situ underground pyrolysis process of tar-rich coal more scientifically, the effect of temperature and pressure on the distribution of pyrolysis products should be clarified. This paper selected the typical components in five distillates of light tar, phenol tar, naphthalene tar, washing tar, and anthracene tar as the main reaction products. 32 typical secondary reactions were constructed. Based on the thermodynamic analysis strategy, the variation of the Gibbs free energy and equilibrium constant of secondary reactions was investigated. The results showed that pressure mainly affected the reaction characteristics of molecule-increasing reactions. The Gibbs free energy value of the molecule-increasing reactions increased with increasing pressure. The trend that the reaction could proceed spontaneously gradually weakened. The initial temperature of some reactions that could proceed spontaneously would need to increase by dozens or even hundreds of degrees. Due to the influence of formation pressure, the generation of related components of light tar, naphthalene tar, washing tar, and anthracene tar would be inhibited to varying degrees in the in situ underground pyrolysis process. The secondary reactions related to phenol tar were equimolecular reactions, which were almost unaffected by stratal pressure. Axial pressure and confining pressure of different coal seam depths should be considered in the process of in situ underground pyrolysis.

Uncovering and engineering the mechanical properties of the adhesion GPCR ADGRG1 GAIN domain

Key cellular functions depend on the transduction of extracellular mechanical signals by specialized membrane receptors including adhesion G-protein coupled receptors (aGPCRs). While recently solved structures support aGPCR activation through shedding of the extracellular GAIN domain, the molecular mechanisms underpinning receptor mechanosensing remain poorly understood. When probed using single-molecule atomic force spectroscopy and molecular simulations, ADGRG1 GAIN dissociated from its tethered agonist at forces significantly higher than other reported signaling mechanoreceptors. Strong mechanical resistance was achieved through specific structural deformations and force propagation pathways under mechanical load. ADGRG1 GAIN variants computationally designed to lock the alpha and beta subdomains and rewire mechanically-induced structural deformations were found to modulate the GPS-Stachel rupture forces. Our study provides unprecedented insights into the molecular underpinnings of GAIN mechanical stability and paves the way for engineering mechanosensors, better understanding aGPCR function, and informing drug-discovery efforts targeting this important receptor class.

[Current practices in the harmonisation of autoantibodies test]

Standardisation and harmonisation of the detection of autoantibodies is important for the clinical application of autoantibodies. However, achieving complete standardisation is difficult and involves several challenges due to the complexity and particularity of autoantibody detection. Harmonisation is feasible and valued, but it involves all aspects and processes of autoantibody detection. Based on the consensus and practice of the clinical application of autoantibody detection in recent years, we discuss harmonisation in this review.

Unravel the regulatory mechanism of Yrr1p phosphorylation in response to vanillin stress in Saccharomyces cerevisiae

Improving the resistance of Saccharomyces cerevisiae to vanillin, derived from lignin, will benefit the design of robust cell factories for lignocellulosic biorefining. The transcription factor Yrr1p mediates S. cerevisiae resistance to various compounds. In this study, eleven predicted phosphorylation sites were mutated, among which 4 mutants of Yrr1p, Y134A/E and T185A/E could improve vanillin resistance. Both dephosphorylated and phosphorylated mutations at Yrr1p 134 and 185 gathered in the nucleus regardless of the presence or absence of vanillin. However, the phosphorylated mutant Yrr1p inhibited target gene expression, while dephosphorylated mutants promoted expression. Transcriptomic analysis showed that the dephosphorylated Yrr1p T185 mutant, under vanillin stress, upregulated ribosome biogenesis and rRNA processing. These results demonstrate the mechanism by which Yrr1p phosphorylation regulates the expression of target genes. The identification of key phosphorylation sites in Yrr1p offers novel targets for the rational construction of Yrr1p mutants to improve resistance to other compounds.

[Changes of serum calcium and bone turnover markers in maintenance hemodialysis patients treated with denosumab]

A total of 20 patients (8 males and 12 females) aged (64.8±13.9) years who underwent regular hemodialysis and had bone loss or osteoporosis in Peking University People's Hospital from July to December 2021 were recruited. Sixty milligrams of denosumab were given subcutaneously. The average serum calcium decreased by 0.31 mmol/L and 40% (8/20) of the patients had hypocalcemia one month after treatment. The markers of bone turnover began to decrease 3 days after treatment, and continued to decrease until 5 months after denosumab medication. Multivariate logistic regression analysis failed to detect any independent risk factor for hypocalcemia (R²=0.516, P=0.021). Therefore, denosumab can significantly inhibit bone turnover in hemodialysis patients, however, patients with denosumab medication are more prone to hypocalcemia.

Exploring the Dehydrogenation Reaction Pathway of Perhydro-Polycyclic Aromatic Hydrocarbons over the Pt/Al2O3 Catalyst as Liquid Organic Hydrogen Carriers by In Situ DRIFT

Polycyclic aromatic hydrocarbons (PAHs) have been paid more attention as liquid organic hydrogen carriers (LOHCs) because of their high hydrogen storage, easy transportation, low price, and other advantages. Dehydrogenation is the key point of the PAH hydrogen storage. However, the dehydrogenation reaction rate of perhydro-PAHs is slow, and their pathway is still not clear. To clarify the PAH dehydrogenation pathway, three kinds of perhydro-PAHs containing six-membered rings (methylcyclohexane, perhydro-diphenylmethane, and perhydro-dibenzyltoluene) are selected, and their dehydrogenation processes over the Pt/Al₂O₃ catalyst are carried out by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFT). It was found that the dehydrogenation in the six-membered ring started in the para position of the -CH₃ group, and then, the six-membered ring was transformed into a benzene ring gradually. Between the six-membered rings, dehydrogenation started from the side ring, which has fewer groups.

[Exploration of pathogenesis and clinical diagnosis and treatment for portal vein thrombosis formation]

Portal vein thrombosis (PVT) refers to the thrombosis of the main portal vein and/or branches, with or without mesenteric vein and splenic vein thrombosis, and is the most common cause of extrahepatic portal vein obstruction. It is latent under chronic conditions and is often detected accidentally during physical examinations or liver cancer screenings. Notably, the understanding of PVT management is still limited, both at home and abroad. Therefore, the purpose of this article is to provide a reference for clinical diagnosis and treatment of PVT formation by summarizing the basis and standards for clinical diagnosis and treatment based on representative research with a large sample size and new perspectives with recent guidelines and consensus.

[Evaluation of diagnostic efficacy of digital liquid chip method for detection of specific antineutrophil cytoplasmic antibodies]

To explore the clinical diagnostic efficacy of antineutrophil cytoplasmic antibody associated vasculitis (AAV) by comparing the consistency and coincidence rate of serum anti-myeloperoxidase (MPO) antibody and anti-protease 3 (PR3) antibody detected by digital liquid chip method (DLCM) and enzyme-linked immunosorbent assay (ELISA). To provide reference for the selection of detection methods of anti-MPO antibody and anti-PR3 antibody in clinical laboratory. This study is a cross-sectional study, a total of 307 cases of antineutrophil cytoplasmic antibodies were detected in the Department of Clinical Immunology, West China Hospital of Sichuan University from January to March 2021. The serum samples and related clinical information were collected. At the same time, the levels of anti-MPO antibody and anti-PR3 antibody in serum samples were detected by ELISA and DLCM, indirect immunofluorescence (IIF) was used to re-test the differential samples between the two methods. SPSS 26.0 was used to analyze the test results, Cohen's kappa coefficient analysis was used to compare the consistency of the two methods, and paired chi-square test was used to compare the sensitivity and specificity of the two methods to AAV. The results showed that the positive cases of anti-MPO antibody detected by ELISA and DLCM were 63 and 44, and the negative cases were 244 and 263; the positive cases of anti-PR3 antibody detected by ELISA and DLCM were 34 and 28, and the negative cases were 273 and 279. The results of anti-MPO antibody and anti-PR3 antibody detected by the two methods had good consistency and coincidence rate, in which the total coincidence rate of anti-MPO antibody was 92.51%, the positive coincidence rate was 66.67%, and the negative coincidence rate was 99.18%. The results of consistency analysis showed that kappa=0.741 had well consistency. The total coincidence rate of anti-PR3 antibody is 96.74%, the positive coincidence rate is 76.47%, and the negative coincidence rate is 99.27%. The consistency analysis results show that kappa=0.821 had strong consistency. The results of IIF re-test of differential samples showed that the coincidence rate between DLCM and IIF was higher. The results of comparative analysis of anti-MPO antibody and anti-PR3 antibody showed that the specificity of DLCM was better than that of ELISA, and its sensitivity was lower than that of ELISA. In conclusion, the results of anti-MPO antibody and anti-PR3 antibody detected by DLCM were consistent with those of ELISA. In the combined detection of anti-MPO antibody and anti-PR3 antibody, the specificity of DLCM is better than that of ELISA.

A few-shot learning-based eye diseases screening method

OBJECTIVE

This study aims to construct a brand-new ophthalmic disease screening task and establish a practically valuable ophthalmic disease screening model in the case of insufficient data.

MATERIALS AND METHODS

The main methods are as follows: firstly, we mixed data from different sources (these data may come from different cameras, including different fundus diseases) to get a new dataset. Based on this dataset, we conducted subsequent experiments on fundus multi-disease screening. However, in the past public datasets, each dataset often only corresponded to the screening diagnosis of one disease. Secondly, we proposed a method to simulate the characteristics of different fundus cameras by using a method based on style transfer, and to augment the training data, so that the model could learn the features of ophthalmic diseases in a more comprehensive way. Finally, a robust disease screening model based on few-shot learning was constructed on the combined dataset, and compared with benchmark algorithms.

RESULTS

We focused on the study of eye disease screening methods based on the metric-based few-shot learning model, data augmentation methods, and focus on key technologies such as data augmentation based on style transfer. Experiments have shown that our method can significantly improve the generalization ability of the disease screening model.

CONCLUSIONS

By introducing few-shot learning theory and data augmentation based on style transfer into ophthalmic disease screening, the generalization ability of the model is greatly improved, and it has certain practical value.

Accelerated Fatigue Model for Predicting Composite Restoration Failure

An empirical method is proposed to predict the clinical performance of resin composite dental restorations by using laboratory data derived from simple specimens subjected to chemical degradation and accelerated cyclic fatigue. Three resin composites were used to fill dentin disks (2-mm inner diameter, 5-mm outer diameter, and 2 mm thick) made from bovine incisor roots. The specimens (n = 30 per group) were aged with different durations of a low-pH challenge (0, 24, and 48 h under pH 4.5) before being subjected to diametral compression with either a monotonically increasing load (fast fracture) or a cyclic load with a continuously increasing amplitude (accelerated fatigue). The data from 1 material were used to establish the relationship between laboratory time (number of cycles) and clinical time to failure (years) via the respective survival probability curves. The temporal relationship was then used to predict the clinical rates of failure for restorations made of the other 2 materials, and the predictions were compared with the clinical data to assess their accuracy. Although there were significant differences in the fast fracture strength among the groups of materials or durations of chemical challenge, fatigue testing was much better at separating the groups. Linear relationships were found between the laboratory and clinical times to failure for the first material (R2 = 0.90, 0.90, and 0.62 for the 0-, 24-, and 48-h low-pH groups, respectively). The clinical life of restorations made of the other 2 materials was best predicted with data from the 48-h low-pH groups. In conclusion, an accelerated fatigue model was successfully calibrated and applied to predict the clinical failure of resin composite restorations, and the predictions based on data obtained from chemically aged specimens provided the best agreement with clinical data.