Modelling the dynamic gas/particle partitioning process of semi-volatile organic compounds emitted from point sources: Quantitative analysis and impact assessment.

The deleterious impact of pollution point sources on the surrounding environment and human has long been a focal point of environmental research. When considering the local atmospheric dispersion of semi-volatile organic compounds (SVOCs) around the emission sites, it is essential to account the dynamic process for the gas/particle (G/P) partitioning, which involves the transition from an initial state to a steady state. In this study, we have developed a model that enables the prediction of the dynamic process for G/P partitioning of SVOCs, particularly considering the influence from emission. It is important to note that the dynamic processes of the concentrations of SVOCs in particle phase (CP) and in gas phase (CG) differ significantly. These differences arise due to the influence of two critical factors: particulate proportion of SVOCs in the emissions (ϕ0) and octanol-air partitioning coefficient (KOA). The validity of our model was assessed by comparing its predictions of the extremum value of the G/P partitioning quotient (KP) with the results obtained from the steady-state model. Remarkably, the characteristic time (tC), used to evaluate the timescale required for SVOCs to reach steady state, demonstrated different variations with KOA for CP and CG. Additionally, the values of tC were quite different for CP and CG, which were markedly influenced by ϕ0. For some SVOCs with high KOA values, it took approximately 35 h to reach steady state. Furthermore, it was found that the time to achieve 95 % of steady state (t95 ≈ 3tC) could reach approximately 105 h. This duration is sufficient for chemicals to disperse from their emission site to the surrounding areas. Therefore, it is crucial to consider the dynamic process of G/P partitioning in local atmospheric transport studies. Moreover, the influence of ϕ0 should be incorporated into future investigations examining the dynamic process of G/P partitioning.

Closed-Loop Polymer-to-Polymer Upcycling of Waste Poly (Ethylene Terephthalate) into Biodegradable and Programmable Materials.

Poly(ethylene terephthalate) (PET), extensively employed in bottles, film, and fiber manufacture, has generated persistent environmental contamination due to its non-degradable nature. The resolution of this issue requires the conversion of waste PET into valuable products, often achieved through depolymerization into monomers. However, the laborious purification procedures involved in the extraction of monomers pose challenges and constraints on the complete utilization of PET. Herein, a strategy is demonstrated for the polymer-to-polymer upcycling of waste PET into high-value biodegradable and programmable materials named PEXT. This process involves reversible transesterifications dependent on ester bonds, wherein commercially available X-monomers from aliphatic diacids and diols are introduced, utilizing existing industrial equipment for complete PET utilization. PEXT features a programmable molecular structure, delivering tailored mechanical, thermal, and biodegradation performance. Notably, PEXT exhibits superior mechanical performance, with a maximal elongation at break of 3419.2 % and a toughness of 270.79 MJ m-3. These characteristics make PEXT suitable for numerous applications, including shape-memory materials, transparent films, and fracture-resistant stretchable components. Significantly, PEXT allows closed-loop recycling within specific biodegradable analogs by reprograming PET or X-monomers. This strategy not only offers cost-effective advantages in large-scale upcycling of waste PET into advanced materials but also demonstrates its enormous prospect in environmental conservation.

Sesquiterpenoids from the leaves of Chimonanthus nitens.

Two new sesquiterpenoids (1 and 3), one new natural product (2), and two known compounds (4 and 5) were isolated from the leaves of Chimonanthus nitens. Their structures were elucidated by spectroscopic analysis, and the absolute configuration of compound 3 was determined by the X-ray single-crystal diffraction analysis. The cytotoxicity of compounds 1-5 was evaluated at three concentrations on two human breast cancer cell lines (MDA-MB-468 and MDA-MB-231) by MTT assay. As a result, we found that the cytotoxicity was weak even with a concentration of these compounds up to 100 µM.

Prevention of Shivering Post Subarachnoid Block: Comparison between Different Doses of Intravenous Magnesium Sulphate.

Background and Objectives: Shivering is a common complication of subarachnoid block (SAB). Magnesium sulphate has been proven to be effective in preventing shivering. The aim of this study was to compare the effectiveness and adverse effects in hemodynamic parameters between 50 mg/kg and 30 mg/kg of intravenous magnesium sulphate for prevention of shivering post-subarachnoid block. Materials and Methods: Eighty-six patients scheduled for surgery under SAB, aged between 18 to 65 years old with American Society of Anesthesiologists physical status I and II were randomised into two groups. Group A received a bolus of 50 mg/kg, while Group B received 30 mg/kg of intravenous magnesium sulphate, given over a 20 min duration following SAB. Shivering grade was recorded intraoperatively according to the Crossley and Mahajan shivering scale. Mean arterial pressure (MAP), heart rate, tympanic temperature, oxygen saturation and the use of vasopressors were recorded. Results: Forty-five percent of patients in Group A and 20% of patients in Group B did not exhibit shivering (p-value < 0.01). High-grade shivering was observed in 12.5% in Group A and 40% in Group B, respectively (p-value 0.02). The MAP trend was lower in Group B (p-value < 0.01), but the incidence of hypotension was not significant in both groups. The use of vasopressors was also similar between groups. Group B showed a lower oxygen saturation trend (p-value 0.04). The trends of heart rate and tympanic temperature were not significant in both groups. No patients had episodes of bradycardia or oxygen desaturation. Conclusions: In this study, intravenous magnesium sulphate 50 mg/kg is the lowest effective dose for prevention and treatment of high-grade shivering post-SAB without significant hemodynamic adverse events.

Three new cassane-type diterpenoids from Caesalpinia sinensis.

Three new cassane-type diterpenoids, namely, (4S)-6ß,12α,19-trihydroxy-cass-13(15)-en-16,12-olide (1), cass-13(15)-en-​16,12-olide (2), and 12α-hydroxy-cass-13(15)-en-16,12-olide (3), were isolated from the seeds of Caesalpinia sinensis. The structures of 1-3 were established by extensive spectroscopic analysis, and their absolute configurations were assigned by electronic circular dichroism (ECD) calculations. The inhibitory activities against PTP1B of the isolated compounds were evaluated. The results showed that compound 2 possessed PTP1B inhibitory activity with an IC50 value of 217.45 ± 36.4 µM.

3, 4-seco-Isopimarane and 3, 4-seco-pimarane diterpenoids from Callicarpa nudiflora.

A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora, resulting in the characterization of five new 3, 4-seco-isopimarane (1-5) and one new 3, 4-seco-pimarane diterpenoid (6), together with four known compounds. The structures of the new compounds were fully elucidated by extensive analysis of MS, 1D and 2D NMR spectroscopic data, and time-dependent density functional theory (TDDFT) calculation of electronic circular dichroism (ECD) spectra, and DFT calculations for NMR chemical shifts and optical rotations.

Six new cadinane-type sesquiterpenoids from the leaves of Chimonanthus nitens Oliv.

Six new cadinane-type sesquiterpenoids, named Chimnitensin A-F (1-6) were isolated from the leaves of Chimonanthus nitens Oliv. Their structures were elucidated by comprehensive spectroscopic analyses and comparison with structurally related known analogues. In vitro MTT assay showed that all six compounds had cytotoxicity against two selected human breast cancer cell lines (MDA-MB-468 and MDA-MB-231), which indicate their potential of developing into anticancer drugs.

3, 4-seco-Isopimarane and 3, 4-seco-pimarane diterpenoids from Callicarpa nudiflora / 中国天然药物

A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora, resulting in the characterization of five new 3, 4-seco-isopimarane (1-5) and one new 3, 4-seco-pimarane diterpenoid (6), together with four known compounds. The structures of the new compounds were fully elucidated by extensive analysis of MS, 1D and 2D NMR spectroscopic data, and time-dependent density functional theory (TDDFT) calculation of electronic circular dichroism (ECD) spectra, and DFT calculations for NMR chemical shifts and optical rotations.

Non-volatile constituents and pharmacology of Chimonanthus: A review.

Chimonanthus plants widely distributed in southern area of China, which have a long history of edibles and medicine. Phytochemical investigations have shown that Chimonanthus produced 143 non-volatile constituents, including alkaloids, flavonoids, terpenoids, coumarins and others, which exhibit significant anti-oxidant, anti-bacterial, anti-cancer, anti-inflammatory, antihyperglycemic, antihyperlipidemic and other biological activities. On the basis of systematic reviewing of literatures, this article overviews the non-volatile constituents and pharmacology of Chimonanthus from domestic and foreign over the last 30 years (until June 2018), and may provide a useful reference for the further development of Chimonanthus.

Non-volatile constituents and pharmacology of Chimonanthus: A review / 中国天然药物

Chimonanthus plants widely distributed in southern area of China, which have a long history of edibles and medicine. Phytochemical investigations have shown that Chimonanthus produced 143 non-volatile constituents, including alkaloids, flavonoids, terpenoids, coumarins and others, which exhibit significant anti-oxidant, anti-bacterial, anti-cancer, anti-inflammatory, antihyperglycemic, antihyperlipidemic and other biological activities. On the basis of systematic reviewing of literatures, this article overviews the non-volatile constituents and pharmacology of Chimonanthus from domestic and foreign over the last 30 years (until June 2018), and may provide a useful reference for the further development of Chimonanthus.

Intracranial multicentric astrocytoma:A case report and literature review / 吉林大学学报(医学版)

Objective:To report the clinical manifestations of 1 case of intracranial multicentric astrocytoma,and to provide a reference for its clinical diagnosis and treatment.Methods:The clinical data of one patient with intracranial multicentric astrocytomas were retrospectively analyzed and the diagnosis and treatment were summarized,and the relevant literatures were reviewed.Results:The patient was male,25 years old,and admitted to hospital due to the sudden convulsions 1 time 18 d ago.The head MRI scanning and enhanced scanning displayed that the left frontal lobe and corpus callosum knee exited the group of patchy mixed abnormal signals,and the left frontal temporal lobe exited the capsule-like mixed signals.Surgical treatment was performed,and the lesions of the left frontal lobe and corpus callosum knee and left frontal temporal lobe were resected.The difference of the two lesions was observed during the operation(the left frontal and corpus callosum knee lesion was cystic and solid mixed tissue,solid organization accounted for majority,and had internal calcification;the left frontal temporal lobe lesion was cystic and solid mixed tissue,and cystic tissue accounted for the majority).The postoperative pathology showed that the left frontal lobe and corpus callosum knee lesion had locally more intensive cells,and more different cells,and it was diagnosed as astrocytoma(WHO Ⅱ-Ⅲ);the left frontal temporal lobe lesion was diagnosed as astrocytoma(WHO Ⅱ).After operation,the patient recovered well,and it was recommended to continue radiotherapy and chemotherapy.Conclusion:For the patients with intracranial multicentric astrocytomas,active surgical treatment is in favor of prolonging the survival of the patients.Postoperative radiotherapy is still controversial,but chemotherapy should be recommended.

Pneumocephalus caused by congenital mastoid dysplasia:A case report and literature review / 吉林大学学报(医学版)

Objective:To investigate the diagnosis and treatment of one patient with pneumocephalus caused by congenital mastoid dysplasia,and to clarify the clinical features,diagnostic methods and treatment strategies of intracranial accumulation of pneumocephalus.Methods:The patient with ineffective right upper limb activity accompanied stupid speech for 12 h was admitted to hospital.After admission,the head CT and MRI examination were performed again,and the patient was diagnosed as pneumocephalus.The paitent scheduled for stoma repair,neurotrophic treatment,infection prevention and other symptomatic treatments were performed after operation;the patient was instructed avoid cough forcefully,blowing nose,defecating and sneezing to increase the intracranial pressure.Results:Due to congenital dysplasia of mastoid wall,local thinning bones and intense swimming choking cough of the patient destroyed the intracranial pressure balance to form pneumocephalus,the patient scheduled for stoma and damaged dura repair;when discharged from hospital,the patient's right upper limb muscle strength and language function returned to normal;the head CT results showed that pneumocephalus disappeared completely.Conclusion;Pneumocephalus is common in clinic,and its reason is diversiform;it should be combined with the patient's history and imaging findings to explore the causes,the most reasonable treatment measures should be performed in order to relieve the patient's symptoms of increased intracranial pressure,and promote the recovery of neural function.

Chemical constituents of Glechoma longituba / 中草药

Objective To study the chemical constituents of Glechoma longituba. Methods Chemical constituents were extracted by organic solvents, isolated and purified by chromatographic techniques with silica gel, Sephadex LH-20, semi-preparative HPLC, and recrystallization. Their structures were elucidated on the basis of physiochemical and spectral analyses. Results Thirteen compounds were obtained and elucidated as ursolic acid (1), asoleanolic acid (2), protocatechualdehyde (3), betulic acid (4), luteolin (5), β-sitosterol (6), lutin (7), syringic acid (8), 4-acetoxy-3,5-dimethoxybenzoicacid (9), 2,5-dihydroxy-1,4-benzenedicarboxylic acid (10), (E)-3-[4-(carboxymethoxy)-3-methoxyphenyl] acrylic acid (11), emodin (12), and loliolide (13). Conclusion Compounds 8-10 and 12 are isolated from this plant for the first time. Compounds 11 and 13 are isolated from the plants of Glechoma Linn. for the first time.

[Study on the flavonoids from Mosla chinensis 'jiangxiangru'].

OBJECTIVE: To study the chemical constituents of Mosla chinensis 'jiangxiangru'. METHODS: The chemical components were isolated and purified by silica gel and Sephadex LH-20 column chromatography. The chemical structures were elucidated on the basis of physic chemical properties and spectral data. RESULTS: Five compounds have been isolated from Mosla chinensis 'jiangxiangru'. On the basis of spectral analysis and physicochemical properties, the compounds were identified as negletein (I), luteolin (II), quercetin (III), chrysoeriol (IV) and apigenin (V). CONCLUSION: Compounds I-V are obtained from the genus for the first time.

Fumigaclavine C, an fungal metabolite, improves experimental colitis in mice via downregulating Th1 cytokine production and matrix metalloproteinase activity.

In the present paper, the effect of Fumigaclavine C, a fungal metabolite, on experimental colitis was examined. Fumigaclavine C, when administered intraperitoneally once a day, significantly reduced the weight loss and mortality rate of mice with experimental colitis induced by intrarectally injection of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). This compound also markedly alleviated the macroscopic and microscopic appearances of colitis. Furthermore, Fumigaclavine C, given both in vivo and in vitro, showed a marked inhibition on the expression of several inflammatory cytokines, including IL-1beta, IL-2, IL-12alpha, IFN-gamma, TNF-alpha as well as MMP-9 in sacral lymph node cells, colonic patch lymphocytes and colitis tissues from the TNBS colitis mice. Meanwhile, the compound caused a dose-dependent reduction in IL-2 and IFN-gamma from the lymphocytes at the protein level and MMP-9 activity. These results suggest that Fumigaclavine C may alleviate experimental colitis mainly via down-regulating the production of Th1 cytokines and the activity of matrix metalloproteinase.