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The abuse of antibiotics has caused severe environmental issues. Photocatalytic treatment technology has the advantages of high efficiency, strong effectiveness and no secondary pollution, which presents great potential for degrading or removing many kinds of environment pollutants. However, the intermediate products formed during the photocatalytic degradation process of antibiotics may possess greater toxicity than the antibiotics themselves, and the toxicity of most of these intermediates still remains unclear. Therefore, understanding the photocatalytic degradation pathways of antibiotics and obtaining qualitative and quantitative information about the main degradation products are of vital importance for the large-scale application of photocatalytic technology in the removal of antibiotics and other pollutants. Probe electrospray ionization mass spectrometry (PESI-MS) technology, adopting a solid probe as the electrospray ionization emitter, has the advantages of rapid response, low sample consumption, high salt tolerance, and strong resistance to suspended particles. These features make PESI-MS to be an ideal technique for direct analysis of complex systems, such as biological and chemical reactions. In this study, PESI-MS was used to perform continuous real-time in situ monitoring and analysis of the photocatalytic degradation of oxytetracycline (OTC), which photocatalyzed by TiO2 under UV irradiation for 160 min, with spectra collected at a resolution of 1 spectrum per second. The results showed that the intensity of protonated OTC ions decreases progressively during the reaction, and forms product ions at various stages of degradation. 35 Kinds of key degradation products are identified by high time-resolved spectra. Based on the changes in the extracted ion chromatograms (EIC) of these products, 7 major degradation products are screened out and 10 possible degradation pathways are proposed, two of which can lead to the degradation of OTC into lower molecular weight products. Although complete photocatalytic degradation of OTC is not achieved in the experimental conditions, the amount of degradation products observed in this study is significantly higher than those previously reported using various high performance liquid chromatography mass spectrometry (HPLC-MS). Furthermore, in the early stages of the photocatalytic process, products of combined ethyl radicals and ethoxy radicals are detected, which likely are contributed by the ethanol added intentionally in the reaction. The use of organic solvents to reduce solution surface tension during PESI operation at atmospheric pressure is inevitable. In the future, we aim to develop a high-pressure PESI ionization source to resolve this issue, which is expected to reveal a more accurate photocatalytic reaction mechanism and pathway. The findings of this study provide valuable data for understanding the kinetics of photocatalytic reactions and developing new photocatalysts, helping researchers gain a more comprehensive understanding of photocatalytic mechanisms.

The distribution and fractionation of persistent organic pollutants (POPs) in different matrices refer to how these pollutants are dispersed and separated within various environmental compartments. This is a significant study area as it helps us understand the transport efficiencies and long-range transport potentials of POPs to enter remote areas, particularly polar regions. This study provides a comprehensive review of the progress in understanding the distribution and fractionation of POPs. We focus on the contributions of four intermedia processes (dry and wet depositions for gaseous and particulate POPs) and determine their transfer between air and soil. These processes are controlled by their partitioning between gaseous and particulate phases in the atmosphere. The distribution patterns and fractionations can be categorized into primary and secondary types. Equations are developed to quantificationally study the primary and secondary distributions and fractionations of POPs. The analysis results suggest that the transfer of low molecular weight (LMW) POPs from air to soil is mainly through gas diffusion and particle deposition, whereas high molecular weight (HMW) POPs are mainly via particle deposition. HMW-POPs tend to be trapped near the source, whereas LMW-POPs are more prone to undergo long-range atmospheric transport. This crucial distinction elucidates the primary reason behind their temperature-independent primary fractionation. However, the secondary distribution and fractionation can only be observed along a temperature gradient, such as latitudinal or altitudinal transects. An animation is produced by a one-dimensional transport model to simulate conceptively the transport of CB-28 and CB-180, revealing the similarities and differences between the primary and secondary distributions and fractionations. We suggest that the decreasing temperature trend along latitudes is not the major reason for POPs to be fractionated into the polar ecosystems, but drives the longer-term accumulation of POPs in cold climates or polar cold trapping.

In this study, a Ti3C2 MXene@g-C3N4 composite powder (TM-CN) was prepared by the ultrasonic self-assembly method and then loaded onto a carbon nanofiber membrane by the self-assembly properties of MXene for the treatment of organic pollutants in wastewater. The characterization of the TM-CN and the C-TM-CN was conducted via X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometer (FTIR) to ascertain the successful modification. The organic dye degradation experiments demonstrated that introducing an appropriate amount of Ti3C2 MXene resulted in the complete degradation of RhB within 60 min, three times the photocatalytic efficiency of a pure g-C3N4. The C-TM-CN exhibited the stable and outstanding photocatalytic degradation of the RhB solution over a wide range of pH values, indicating the characteristics of the photodegradation of organic pollutants in a wide range of aqueous environments. Furthermore, the results of the cyclic degradation experiments demonstrated that the C-TM-CN composite film maintained a degradation efficiency of over 85% after five cycles, thereby confirming a notable improvement in its cyclic stability. Consequently, the C-TM-CN composite film exhibits excellent photocatalytic performance and is readily recyclable, making it an auspicious eco-friendly material in water environment remediation.

The thermal characteristics of whole goat and bovine milk powder, prepared by vacuum freeze drying, and goat milk powder adulterated with different proportions (75%, 50%, 25%, 10%, 5%, 3% and 1%) of bovine milk powder were analyzed by differential scanning calorimetry (DSC). The results showed that there were differences in DSC thermal characteristics between whole goat and bovine milk powder. Compared with whole goat milk powder, whole milk powder lacked the characteristic melting endothermic peak (b) of fat, and had lower protein melting endothermic peak (c) temperature and enthalpy value but higher enthalpy value for lactose melting decomposition peak (e). According to the presence or absence of endothermic peak b and its enthalpy value, we could judge whether goat milk powder was adulterated with bovine milk powder at levels below 25% and determine adulteration levels. In conclusion, DSC can be used for the analysis and evaluation of the thermal properties of goat milk powder and milk powder and can also be used as a potential tool for quality assurance and authenticity identification in the dairy industry.

Objective To investigate the role of vascular endothelial growth factor (VEGF) and the Wnt/β-catenin signaling pathway in gingival tissues remodeling by measuring the changes in VEGF and β-catenin expression in mouse gingival tissues under hyperocclusion. Methods Thirty male Kunming mice aged four weeks were randomly divided into control group (n=15) and experimental group (n=15). All the right maxillary molars of mice in the experimental group were extracted to establish a hyperocclusion model. On the 3rd, 7th, 14th, 28th, and 56th days after operation, three mice in each group were randomly selected and sacrificed under anesthesia. Their left mandibular first molars with the gingival tissues were isolated. Hematoxylin-eosin (HE) staining was performed to observe the histological changes of the gingiva, and immunohistochemical staining was used to measure the changes in VEGF and β-catenin expression in the gingival tissues. Results The HE staining showed that in the experimental group, the thickness of gingival tissues and the number of blood vessels increased on day 14 after tooth extraction. The results of immunohistochemical examination showed that in the control group, there were no significant differences in the expression of VEGF and β-catenin in the gingival tissues between different time points (P>0.05); while in the experimental group, there were significant differences in that between different time points (F=250.4,343.9,P

BackgroundsThe safety of different sodium-glucose transporter 2 (SGLT-2) inhibitors remains uncertain due to the lack of head-to-head comparisons.MethodsThis network meta-analysis (NMA) was performed to compare the safety of nine SGLT-2 inhibitors in patients with type 2 diabetes (T2DM). PubMed, Embase, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov were searched for studies published in English before August 30, 2022. Published and unpublished randomized controlled trials (RCTs) comparing the safety of individual SGLT-2 inhibitors in patients with T2DM were included. A Bayesian NMA with random effects model was applied. Subgroup and sensitivity analyses were performed. The quality of the evidence was evaluated using the Confidence in Network Meta-Analysis framework.ResultsNine SGLT-2 inhibitors were evaluated in 113 RCTs (12 registries) involving 105,293 adult patients. Reproductive tract infections (RTIs) were reported in 1,967 (4.51%) and 276 (1.01%) patients in the SGLT-2 inhibitor and placebo groups, respectively. Furthermore, pollakiuria was reported in 233 (2.66%) and 45 (0.84%) patients, respectively. Compared to placebo, a significantly higher risk of RTIs was observed with canagliflozin, ertugliflozin, empagliflozin, remogliflozin, dapagliflozin, and sotagliflozin, but not with luseogliflozin and ipragliflozin, regardless of gender. An increased risk of pollakiuria was observed with dapagliflozin [odds ratio (OR) 10.40, 95% confidence interval (CI) 1.60-157.94) and empagliflozin (OR 5.81, 95%CI 1.79-32.97). Remogliflozin (OR 6.45, 95%CI 2.18-27.79) and dapagliflozin (OR 1.33, 95%CI 1.10-1.62) were associated with an increased risk of urinary tract infections (UTIs). Instead, the included SGLT-2 inhibitors had a protective effect against acute kidney injury (AKI). No significant differences were found for hypovolemia, renal impairment or failure, fracture, diabetic ketoacidosis (DKA), amputation, and severe hypoglycemia between the SGLT-2 inhibitor and the placebo groups.ConclusionIn patients with T2DM, dapagliflozin was associated with an increased risk of RTIs, pollakiuria, and UTIs. Empagliflozin increased the risk of RTIs and pollakiuria. Remogliflozin increased the risk of UTIs. None of the SGLT-2 inhibitors showed a significant difference from the placebo for hypovolemia, renal impairment or failure, fracture, DKA, amputation, and severe hypoglycemia. The findings guide the selection of SGLT-2 inhibitors for patients with T2DM based on the patient’s profiles to maximize safety.Systematic review registrationhttps://www.crd.york.ac.uk/prospero, identifier CRD42022334644.

The historical annual loading to, removal from, and cumulative burden in the Arctic Ocean for β-hexachlorocyclohexane (β-HCH), an isomer comprising 5–12% of technical HCH, is investigated using a mass balance box model from 1945 to 2020. Over the 76 years, loading occurred predominantly through ocean currents and river inflow (83%) and only a small portion via atmospheric transport (16%). β-HCH started to accumulate in the Arctic Ocean in the late 1940s, reached a peak of 810 t in 1986, and decreased to 87 t in 2020, when its concentrations in the Arctic water and air were ∼30 ng m−3 and ∼0.02 pg m−3, respectively. Even though β-HCH and α-HCH (60–70% of technical HCH) are both the isomers of HCHs with almost identical temporal and spatial emission patterns, these two chemicals have shown different major pathways entering the Arctic. Different from α-HCH with the long-range atmospheric transport (LRAT) as its major transport pathway, β-HCH reached the Arctic mainly through long-range oceanic transport (LROT). The much higher tendency of β-HCH to partition into the water, mainly due to its much lower Henry's Law Constant than α-HCH, produced an exceptionally strong pathway divergence with β-HCH favoring slow transport in water and α-HCH favoring rapid transport in air. The concentration and burden of β-HCH in the Arctic Ocean are also predicted for the year 2050 when only 4.4–5.3 t will remain in the Arctic Ocean under the influence of climate change.

Tribbles homolog 3(TRIB3,TRB3) is a kind of protein kinase inhibitors involved in a variety of biological processes like apoptosis, stress response, transcription and transcriptional regulation. Obesity is a chronic metabolic disease caused by many factors including lifestyle, endocrine and drug factors. Abnormal expression of TRIB3 in vivo may be involved in the development of obesity, with expansion of adipose tissue and visceral fat leading to metabolic disorders, organ dysfunction, male infertility, various chronic diseases, and increased mortality. Therefore, exploring the mechanism of TRIB3 in obesity may provide new ideas for the diagnosis and treatment of obesity.

To overcome the vulnerability of strong physical unclonable function, the adversarial learning model of strong PUF was presented based on the adversarial learning theory, then the training process of gradient descent algorithm was analyzed under the framework of the model, the potential relationship between the delay vector weight and the prediction accuracy was clarified, and an adversarial sample generation strategy was designed based on the delay vector weight. Compared with traditional strategies, the prediction accuracy of logistic regression under new strategy was reduced by 5.4% ~ 9.5%, down to 51.4%. The physical structure with low overhead was designed corresponding to the new strategy, which then strengthened by symmetrical design and complex strategy to form a new PUF architecture called ALPUF. ALPUF not only decrease the prediction accuracy of machine learning to the level of random prediction, but also resist hybrid attack and brute force attack. Compared with other PUF security structures, ALPUF has advantages in overhead and security.

Myxofibrosarcoma (MFS) is a highly malignant subtype of soft tissue sarcoma, accounting for 5% of cases. Immunotherapy guided by immune cell infiltration (ICI) is reportedly a promising treatment strategy. Here, MFS samples (n = 104) from two independent databases were classified as ICI clusters A/B/C and gene clusters A/B/C. Then, a close relationship between ICI and gene clusters was established. We found that the features of these clusters were consistent with the characteristics of immune-inflamed tumors (cluster C), immune-desert tumors (cluster B), and immune-excluded tumors (cluster A). Moreover, cluster C was sensitive to immunotherapy. Finally, an independent ICI score was established to predict the therapeutic effect, which has prospects for application in guiding immunotherapy during clinical practice.

The development of a platform of clinical electrocardiograph(ECG) big data and diversified internet teaching resources brings opportunities to explore the innovation of ECG teaching mode supported by big data. By analyzing current problems of traditional ECG teaching, this article puts forward three examples of ECG teaching innovation on ECG big data platform: sequential teaching combined with theory and practical training, heuristic teaching based on ECG vector theory and self-directed learning, and expounds their implementation strategies.

This paper assesses the occurrence, distribution, source, and toxicity of polycyclic aromatic hydrocarbons (PAHs), and their methylated form (Me-PAHs) in sewage sludge from 10 WWTPs in Northeastern China was noted. The concentrations of ∑PAHs, ∑Me-PAHs ranged from 567 to 5040 and 48.1 to 479 ng.g−1dw, which is greater than the safety limit for sludge in agriculture in China. High and low molecular weight 4 and 2-ring PAHs and Me-PAHs in sludge were prevalent. The flux of sludge PAHs and Me-PAHs released from ten WWTPs, in Heilongjiang province, was calculated to be over 100 kg/year. Principal component analysis (PCA), diagnostic ratios and positive matrix factorization (PMF) determined a similar mixed pyrogenic and petrogenic source of sewage sludge. The average values of Benzo[a]pyrene was below the safe value of 600 ng.g−1 dependent on an incremental lifetime cancer risk ILCR of 10−6. Sludge is an important source for the transfer of pollutants into the environment, such as PAHs and Me-PAHs. Consequently, greater consideration should be given to its widespread occurrence.

Polycyclic aromatic hydrocarbons (PAHs), 33 methylated PAHs (Me-PAHs), and 14 nitrated PAHs (NPAHs) were measured in wastewater treatment plants (WWTPs) to study the removal efficiency of these compounds through the WWTPs, as well as their source appointment and potential risk in the effluent. The concentrations of ∑PAHs, ∑Me-PAHs, and ∑NPAHs were 2.01–8.91, 23.0–102, and 6.21–171 µg/L in the influent, and 0.17–1.37, 0.06–0.41 and 0.01–2.41 µg/L in the effluent, respectively. Simple Treat 4.0 and meta-regression methods were applied to calculate the removal efficiencies (REs) for the 63 PAHs and their derivatives in 10 WWTPs and the results were compared with the monitoring data. Overall, the ranges of REs were 55.3–95.4% predicated by the Simple Treat and 47.5–97.7% by the meta-regression. The results by diagnostic ratios and principal component analysis PCA showed that “mixed source” biomass, coal composition, and petroleum could be recognized to either petrogenic or pyrogenic sources. The risk assessment of the effluent was also evaluated, indicating that seven carcinogenic PAHs, Benzo[a]pyrene, Dibenz[a,h]anthracene, and Benzo(a)anthracene were major contributors to the toxics equivalency concentrations (TEQs) in the effluent of WWTPs, to which attention should be paid.

The partitioning of semi-volatile organic compounds (SVOCs) between gas and particle phases plays a crucial role in their long-range transport and health risk assessment. However, the accurate predicting of the gas/particle (G/P) partitioning quotient (KP') remains a challenge, especially for the light molecular weight (LMW) SVOCs due to their upward deviation from the equilibrium state. Based on the diurnal study of concentrations and KP' values for methylated polycyclic aromatic hydrocarbons (Me-PAHs), it was found that the diurnal variations of methylated naphthalenes (Me-Naps, one type of LMW SVOCs) were different from other Me-PAHs, that KP' values during daytime were higher than that during nighttime, and the regression lines of log KP' versus log KOA (octanol-air partitioning coefficient) for daytime and nighttime were non-overlap. It was found that the higher gaseous degradation of Me-Naps during daytime than that during nighttime should be responsible for their special diurnal variation of KP', which provided a new explanation for the non-equilibrium behavior of KP' of LMW SVOCs. Moreover, the influence of gaseous degradation on the deviation of KP' from the equilibrium state was deeply studied based on a theoretical model considering particulate proportion in emission (0). It was found that the deviation occurred when 0FGR (FGR, degradation flux of gas phase) cannot be ignored when compared with FGP (flux from gas phase to particle phase). It can be concluded that the deviation was not only related to the gaseous degradation rate (kdeg), but also related to 0. Furthermore, an amplification of KP' ranging from 1 to 8.4 times under different 0 (0 to 1) in the temperature range of -50 to 50°C was estimated based on the individual degradation rates of Me-Naps and three LMW PAHs. In summary, it can be concluded that the influence of gaseous degradation should also be considered for the G/P partitioning models of SVOCs, especially for the LMW SVOCs, which provided new insights into the related fields. [ABSTRACT FROM AUTHOR]

Objective To explore the clinicopathological features of cerebellar lipidized medulloblastoma. Methods The clinical manifestations， neuroimaging, histopathological and immunohistochemical features were analysed in one case of lipidized medulloblastoma in the cerebellar vermis. Related literatures were reviewed. Results A 26 ⁃ year ⁃ old man presented with intermittent headache，accompanied by dizziness, nausea and vomiting. The magnetic resonance imaging (MRI) demonstrated a mass located the cerebellar vermis convex to the fourth ventricle. The tumor with well⁃ demarcated boundary was homogeneous hypointense on T1 weighted and heterogeneous hyperintense on T2 weighted images, and enhanced brilliantly and homogenously on contrast. The patient subsequently underwent gross total mass resection. Microscopically，there was diffuse infiltration by high cellularity of tumor cells. The cytoplasm were thin eosinophilic to amphophilic. The neoplastic cells showed round to oval hyperchromatic nuclei with a delicately stippled chromatin and occasional conspicuous nucleoli and numerous mitotic figures were also present. Thin⁃wall vascular proliferation was detected. Lipid⁃laden cells were focally distributed in tumor tissue. On immunohistochemical examination, the neoplasm was reactive for CD56 and synaptophysin (Syn), focally positive for neurofilament protein (NF), weakly positive for oligodendrocyte lineage transcription factor 2 (Olig⁃2), and negtive for nestin, neuronal nuclei (NeuN), S⁃100 protein (S ⁃ 100), glial fibrillary acidic protein (GFAP) and epithelial membrane antigen (EMA). TP53 protein was over expressed in 10% of tumor cells. Ki ⁃ 67 antigen labeling index were about 40% . Conclusion Cerebellar lipidized medulloblastoma is rare. Neuroimaging showed space occupying lesion in cerebellar vermis. Histologically, the tumor cells were consisted of monotonous, round cells with focal accumulations of lipidized cells. The differential diagnosis include liponeurocytoma and ependymoma and so on. DOI：10.3969/j.issn.1672⁃6731.2012.03.014