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Snow cover is the most common upper boundary condition influencing the soil freeze-thaw process in the black soil farming area of northern China. Snow is a porous dielectric cover, and its unique physical properties affect the soil moisture diffusion, heat conduction, freezing rate and other variables. To understand the spatial distribution of the soil water-heat and the variable characteristics of the critical depth of the soil water and heat, we used field data to analyze the freezing rate of soil and the extent of variation in soil water-heat in a unit soil layer under bare land (BL), natural snow (NS), compacted snow (CS) and thick snow (TS) treatments. The critical depth of the soil water and heat activity under different snow covers were determined based on the results of the analysis, and the variation fitting curve of the difference sequences on the soil temperature and water content between different soil layers and the surface 5-cm soil layer were used to verify the critical depth. The results were as follows: snow cover slowed the rate of soil freezing, and the soil freezing rate under the NS, CS and TS treatments decreased by 0.099 cm/day, 0.147 cm/day and 0.307 cm/day, respectively, compared with that under BL. In addition, the soil thawing time was delayed, and the effect was more significant with increased snow cover. During freeze-thaw cycles, the extent of variation in the water and heat time series in the shallow soil was relatively large, while there was less variation in the deep layer. There was a critical stratum in the vertical surface during hydrothermal migration, wherein the critical depth of soil water and heat change gradually increased with increasing snow cover. The variance in differences between the surface layer and both the soil water and heat in the different layers exhibited "steady-rising-steady" behavior, and the inflection point of the curve is the critical depth of soil freezing and thawing. This critical layer is a demarcation point between frozen soil and non-frozen soil, delineating the boundary between soil water and heat migration and non-migration. Furthermore, with increasing snow cover thickness and increasing density, the critical depth gradually increased. [ABSTRACT FROM AUTHOR]

Background Unruptured intracranial aneurysm treatment aims to reduce the risk of aneurysm rupture and bleeding, relieves symptoms and improve the quality of life for patients. This study aimed to assess the safety and efficacy of Pipeline Embolization Device (PED, Covidien/Medtronic, Irvine, CA) treatment for intracranial aneurysms presenting with mass effect in real-world settings.Methods We selected patients from the PED in China Post-Market Multi-Center Registry Study with mass effect presentation. The study endpoints included postoperative mass effect deterioration and mass effect relief at follow-up (3–36 months). We conducted multivariate analysis to identify factors associated with mass effect relief. Subgroup analyses by aneurysm location, size and form were also performed.Results This study included 218 patients with a mean age of 54.3±11.8 years and a female predominance of 74.0% (162/218). The postoperative mass effect deterioration rate was 9.6% (21/218). During a median follow-up period of 8.4 months, the mass effect relief rate was 71.6% (156/218). Notably, immediate aneurysm occlusion following treatment was significantly associated with mass effect relief (OR 0.392, 95% CI, 0.170 to 0.907, p=0.029). Subgroup analysis demonstrated that adjunctive coiling contributed to mass effect relief in cavernous aneurysms, while dense embolism impeded symptom relief in aneurysms

Background Hypertension is widely acknowledged as a significant contributory factor to the heightened risk of intracranial aneurysm rupture. Nevertheless, the impact of hypertension management on the outcomes subsequent to aneurysmal subarachnoid haemorrhage (aSAH), particularly concerning the severity of aSAH, remains an underexplored area.Methods We conducted a retrospective analysis using data from a prospectively multicentre cohort of 4545 patients with aSAH in China. Premorbid hypertension status and the utilisation of antihypertensive medications prior to admission were set as key exposure factors. The primary outcomes encompassed unfavourable clinical grading scales observed on admission. Employing multivariable logistic regression, we explored the association between premorbid hypertension status, preadmission use of renin-angiotensin-aldosterone system (RAAS) inhibitors and unfavourable clinical grading scales.Results In comparison to patients with normal blood pressure, only uncontrolled hypertension demonstrated a significant and independent association with an elevated risk of poor outcomes on the Hunt-Hess scale (OR=1.799, 95% CI 1.413 to 2.291, p

Objective To evaluate the recanalization efficacy and safety of a novel stent retriever in a swine model of acute arterial occlusion. Methods The JRecan thrombectomy device, a stent retriever with a weaving stent design, was evaluated in 18 occluded cervicocerebral vessels of swine. The flow restoration effect immediately upon deployment, the reperfusion rate after retrieval, thromboembolic events, and complications were assessed. The histologic structure of the renal arteries after retriever passage was measured to further assess the safety of JRecan. Results Immediate flow restoration was achieved in 66.7% of occlusions (12/18). The reperfusion rate was 94.4% (two Thrombolysis in Cerebral Infarction (TICI) 2b and 15 TICI 3). Distal thromboembolic events did not occur. Microscopic examination of the arteries after retrieval showed mild degrees of endothelial loss in 96.6% (29/30), fibrin or platelet deposition in 53.3% (16/30), and disruption of the internal elastic lamina in 10% (3/30), without severe pathologic lesions. Conclusions The JRecan is highly effective at clot removal with a favorable safety profile and merits further development as a stent retriever for the treatment of acute ischemic stroke. [ABSTRACT FROM AUTHOR]

With the development of an agricultural economy, agricultural water demand has increased. The increased demand has resulted in extremely unbalanced development and utilization of surface and groundwater and has seriously affected the sustainable development of a regional economic ecology. To understand the law covering the complex phenomena of groundwater systems, it is important to select the appropriate method to measure the complexity of groundwater resource systems. Previous analyses of regional groundwater resource systems had the shortcomings of ignoring the system complexity as well as difficulty to realize the importance in deed of scientific management of groundwater resources. The Jiansanjiang Administration research platform was used to detect the monthly depth series of groundwater complexity with an aim to determine the complexity of the series. The average complexity of groundwater table depth series of each subarea on a monthly basis by was determined adopting symbolic dynamics. The diagnostic analysis results showed that the complexity of monthly groundwater table depth series of each subarea of the Jiansanjiang Administration featured highest complexity in the northern area, lowest complexity in the middle area, and medium complexity in the southern area. Local agricultural production activities are the key driving factors of dynamic change of groundwater table depth. Compared with the traditional rescaled range (R/S) analysis fractal theory and wavelet entropy theory, they showed that the results of diagnostic analysis by symbolic dynamics have a higher degree of reasonableness, providing an effective method for the research on the complexity of regional hydrological processes. The research results have uncovered the evolution characteristic of complexity of the local groundwater depth, providing a scientific basis for partition management and sustainable utilization of regional groundwater resources. The goal of the research is the rational exploitation of Jiansanjiang groundwater. The study results reveal the complex spatial distribution pattern of local groundwater depth and provide scientific evidence for management and sustainable utilization of regional groundwater resources. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a worldwide malignancy of high incidence and mortality. At present, there is a lack of effective drugs against CRC. The B-cell leukemia/lymphoma 2 (Bcl-2) protein family members are considered to be closely associated with tumorigenesis and the chemoresistance of CRC. As a novel gossypol derivative targeting antiapoptotic proteins of the Bcl-2 family, apogossypolone (ApoG2) exhibits antitumor properties in various cancer types, although its effects against CRC remain to be fully elucidated. In the present study, the cytotoxicity of ApoG2 in vitro on CRC cells was investigated, with the aim of elucidating the underlying mechanism. Using an MTT assay, ApoG2 was revealed to inhibit the growth of the HT29, SW480 and HCT116 CRC cell lines in a dose- and a time-dependent manner. Hoechst staining revealed that ApoG2 induced CRC cell apoptosis, marked by morphological changes, including cell shrinkage and nuclear fragmentation. Flow cytometric analysis also detected a higher apoptotic ratio following treatment with ApoG2. The ratio was dependent upon the concentration of ApoG2, which the cells were exposed to, and the duration of the exposure. Western blot analysis and immunoprecipitation experiments revealed that ApoG2 treatment led to the downregulation of the protein expression of Mcl-1, and the interruption of the binding of Mcl-1 to the protein Bax. Furthermore, treatment with ApoG2 led to the release of cytochrome c into the cytoplasm and the activation of caspases 3 and 7. The present study revealed that ApoG2 inhibited the proliferation of the CRC cell lines through mitochondrial signaling pathway-dependent apoptosis, which may be associated with the disruption of the function of the Mcl-1 protein by ApoG2. [ABSTRACT FROM AUTHOR]

Compared with peppermint oil, natural peppermint has more ingredients, a layered fragrance, and a green colour. It has been widely used as a nutritional additive, herbal tea, food flavouring or colouring. In this work, the retention of volatile flavour compounds of peppermint powders was enhanced by propylene glycol, a reagent that enhances hydrogen bonds and moisture absorption. The levels of influence of propylene glycol content on the retention of different volatile flavour compounds, moisture absorption and water distribution were evaluated by GC–MS, dynamic water absorption instrument (DVS), and low‐field nuclear magnetic resonance (LF‐NMR), respectively. GC–MS analysis showed that the volatile substances of peppermint powders (PMs) without propylene glycol were reduced to 22 kinds after storage for 90 days, and the total amount of volatile substances remained at 40.94%; PG2 with 2% propylene glycol had the best flavour retention. After 90 days of storage, the residual percentage of volatile flavour compounds of PG2 was approximately 72.56%, which was significantly increased compared with that of PM. The DVS results suggested that all the peppermint powders adopted a type III moisture absorption isotherm, and they all had multilayer adsorbed water. PG2 had the best moisture retention capacity and the highest hygroscopic hysteresis, while PG4 with a high propylene glycol content had a relatively poor moisture retention capacity. Similarly, LF‐NMR analysis showed that PG2 had a higher proportion of bound water and lower relaxation times T21 and T22 under different humidity conditions, indicating that it had the strongest water binding capacity. The correlation analysis showed that there was a significant positive correlation between the residual volatile compounds of peppermint powders and the peak area of bound water A21. The higher the proportion of strongly bound water in peppermint particles was, the more residual volatile substances were identified in peppermint particles. These results show that peppermint particles supplemented with propylene glycol can significantly improve the flavour retention ability of peppermint powders. In short, the results could be applied to the storage stability and quality control of peppermint products. [ABSTRACT FROM AUTHOR]

Based on a winter field experiment between 2016 and 2017, four treatments (bare land (BL), natural snowfall coverage (NS), 5-cm-deep straw + natural snowfall coverage (SC5), and 10-cm-deep straw + natural snowfall coverage (SC10)) were established to determine the effects of the different treatments on soil temperature at the soil surface and at depths of 10 cm, 20 cm, and 30 cm. The environmental factors of ambient temperature, ambient humidity, water vapor pressure, 10-min wind speed, total radiation, net radiation, and long wave radiation were obtained from the weather station in the study area. Through correlation, multiple regression, and stepwise regression analysis, models for dynamic simulation of the tillage-layer soil temperature were constructed for analyzing the relation between tillage-layer soil temperature and environmental factors. The results showed that the environmental factors were all significantly correlated with tillage-layer temperature at the 0.01 level; when the impacts of other environmental factors were excluded, the correlations decreased significantly. The dynamic simulation models for tillage-layer soil temperature under different coverage conditions were different, and the larger the coverage amount, the fewer the environmental factors that could affect the tillage-layer temperature. The coefficients of determination of the prediction results of the dynamic models for the tillage-layer soil temperature under the four treatments (BL, NS, SC5, and SC10) were 0.8385, 0.7110, 0.7283, and 0.6216, respectively. The prediction had a high accuracy and can accurately depict the dynamic changes of the tillage-layer soil temperature. The results provided a theoretical basis for the efficient utilization of farmland soil water and heat resources. [ABSTRACT FROM AUTHOR]

Background: In acute ischemic stroke, there is uncertainty regarding the benefit and risk of administering intravenous alteplase before endovascular thrombectomy., Methods: We conducted a trial at 41 academic tertiary care centers in China to evaluate endovascular thrombectomy with or without intravenous alteplase in patients with acute ischemic stroke. Patients with acute ischemic stroke from large-vessel occlusion in the anterior circulation were randomly assigned in a 1:1 ratio to undergo endovascular thrombectomy alone (thrombectomy-alone group) or endovascular thrombectomy preceded by intravenous alteplase, at a dose of 0.9 mg per kilogram of body weight, administered within 4.5 hours after symptom onset (combination-therapy group). The primary analysis for noninferiority assessed the between-group difference in the distribution of the modified Rankin scale scores (range, 0 [no symptoms] to 6 [death]) at 90 days on the basis of a lower boundary of the 95% confidence interval of the adjusted common odds ratio equal to or larger than 0.8. We assessed various secondary outcomes, including death and reperfusion of the ischemic area., Results: Of 1586 patients screened, 656 were enrolled, with 327 patients assigned to the thrombectomy-alone group and 329 assigned to the combination-therapy group. Endovascular thrombectomy alone was noninferior to combined intravenous alteplase and endovascular thrombectomy with regard to the primary outcome (adjusted common odds ratio, 1.07; 95% confidence interval, 0.81 to 1.40; P = 0.04 for noninferiority) but was associated with lower percentages of patients with successful reperfusion before thrombectomy (2.4% vs. 7.0%) and overall successful reperfusion (79.4% vs. 84.5%). Mortality at 90 days was 17.7% in the thrombectomy-alone group and 18.8% in the combination-therapy group., Conclusions: In Chinese patients with acute ischemic stroke from large-vessel occlusion, endovascular thrombectomy alone was noninferior with regard to functional outcome, within a 20% margin of confidence, to endovascular thrombectomy preceded by intravenous alteplase administered within 4.5 hours after symptom onset. (Funded by the Stroke Prevention Project of the National Health Commission of the People's Republic of China and the Wu Jieping Medical Foundation; DIRECT-MT ClinicalTrials.gov number, NCT03469206.)., (Copyright © 2020 Massachusetts Medical Society.)