我国化妆品产品稳定性研究与管理现状的探讨

化妆品的稳定性是评价化妆品质量与安全的重要因素,也是化妆品使用性与功效性的保障。本文对比了全球化妆品稳定性研究的监管体系和稳定性文件情况,梳理了国内化妆品产品有效期、稳定性及监管等相关文件的内容。通过对“监管、协会和企业”三个板块电子问卷调查结果,分析我国目前化妆品产品稳定性研究现状,发现工作开展面临的主要问题。借鉴国外化妆品产品稳定性研究的经验及我国食品药品等行业领域产品稳定性研究情况,对我国化妆品产品稳定性研究方向、技术文件的制定和监管服务提出建议。

基于网络药理学的化妆品原料粉防己抗敏作用机制分析

采用网络药理学方法探索化妆品原料粉防己对敏感肌肤的抗敏作用机制。通过TCMSP、中国知网、PubMed等数据库收集粉防己的主要化学成分,并利用SwissTargetPrediction预测其靶点,与从Genecards数据库获得的疾病靶点取交集后采用String数据库构建蛋白质相互作用(PPI)网络,采用Cytoscape3.9.1软件分析获得核心靶点,再运用DAVID在线数据库对核心靶点进行基因GO功能分析和KEGG通路富集分析,Cytoscape3.9.1软件构建粉防己活性成分-靶点交互网络。共筛选出粉防己潜在活性成分50个及相应靶点682个,敏感肌肤疾病相关靶点2389个,交集靶点295个,其中核心靶点39个。GO富集分析结果显示,39个核心靶点主要涉及蛋白磷酸化、信号转导、转录调控、基因表达等多种生物学过程。KEGG通路富集分析结果显示,粉防己发挥抗敏作用可能与VEGF信号通路、HIF-1信号通路、ErbB信号通路、PI3K-Akt信号通路密切相关。粉防己中荷包牡丹碱、千金藤素、防己诺林碱等活性成分可能是通过作用于JAK2、JAK3、SYC等靶点发挥抗敏作用,体现了粉防己多成分-多靶点-多通路的作用特点。

The effect of thermal fluid derived from mud diapir on sandstone reservoirs in the Yinggehai Basin, South China Sea

The underground thermal fluid is one of the significant factors controlling the formation and quality of reservoirs.The Huangliu Formation(N_(1)h)in YF1 area of the central depression belt in the Yinggehai Basin,South China Sea,is characterized by intense thermal fluid activities related to mud diapir and large-scale shallow-water gravity flow deposits.The multi-episodic invasion of high-temperature and CO_(2)-rich thermal fluid into the formation induces complex water-rock reaction during diagenetic pro-cess,providing a preferable investigation opportunity for revealing how thermal fluid affects reservoir quality.This study characterizes the reservoirs in the formation through core and thin section analyses as well as physical property test.The reservoirs are dominated by fine-grained sandstone characterized by medium porosity(15.2-21.3%)and lower permeability(0.56-15.75mD).Based on an analysis of casting thin section,cathode luminescence(CL),scanning electron microscope(SEM),carbon and oxygen isotope,inclusion test,and electron-probe microanalysis(EPMA),we systematically investigate the diagenetic patterns and pore evolution process for the reservoirs in the formation.The episodic invasion of thermal fluid occurred approximately 0.4 Ma ago plays an important role in controlling reservoir development:The CO_(2)-rich formation water induces massive late-stage dissolution,resulting in a higher proportion of dissolved pores(38.7-46.4%),which improves the porosity of reservoirs at a depth of 2600-3100 m.Nevertheless,the late dissolution together with carbonate cementation occurred in closed diagenetic system blocks most seepage channels.Furthermore,the relatively high level clay mineral transformation in the YF1 area leads to a higher content of authigenic illite(44-62%)in the formation.Massive authigenic illite severely blocks the pore throats in fine sandstone,reducing permeability.This study offers an insight to the understanding of mud diapir-derived thermal fluid affecting and controlling the quality of reservoirs in some areas of the Yinggehai Basin.

基于超级微波消解-电感耦合等离子体质谱法分析儿童化妆品中的40种元素

为了解儿童化妆品中元素含量的情况,建立了超级微波消解-电感耦合等离子体质谱法测定儿童化妆品中40种元素的方法,方法学验证后,对75批样品进行了测定和检测结果分析评价。结果表明,该方法满足化妆品的检测要求,且方法简便、快速、准确、适用儿童化妆品中元素的测定。汞、铅、砷、镉元素检测结果均符合规定;镍、铬、钡三种元素,其中2批样品的钡元素测定结果分别为0.88和0.62 mg/kg,1批镍元素测定结果为6.71 mg/kg,其余样品三种元素的检测结果均小于0.5 mg/kg;钛元素测定结果为0.2~82.5 mg/kg;1批银元素的测结果为6.83 mg/kg;16种稀土元素均小于0.1 mg/kg,其余元素均小于0.3 mg/kg。建议在儿童化妆品中,对镍、铬、钡三种元素及其盐开展限度研究、对钛含量进行健康风险评估、对氰化银钾的检测方法进行完善,稀土元素和其余元素安全状况良好,安全风险较低。

高效液相色谱-质谱法测定健美类化妆品中咖啡因等33种成分

建立高效液相色谱-质谱法筛查化妆品中咖啡因等33种成分的分析方法。样品经甲醇溶解提取,高速离心后,经0.22μm滤膜过滤,采用Atlantis^(TM)dC18(2.1 mm×100 mm×3μm)色谱柱分离,0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,柱温为30℃,流速0.3 mL/min,基质加标标准曲线测定咖啡因等33种成分。结果表明,咖啡因等33种成分在相应的质量浓度范围内线性关系良好,相关系数(r)均大于0.99;回收率为80.7%~118.2%,相对标准偏差(RSDs)均小于10%,检出限为0.003~0.015μg/g。该方法操作简单、快速,适用于健美类化妆品中咖啡因等33种成分的检测。

EVs-mediated delivery of CB2 receptor agonist for Alzheimer’s disease therapy

Alzheimer’s disease(AD)is a typical neurodegenerative disease that leads to irreversible neuronal degeneration,and effective treatment remains elusive due to the unclear mechanism.We utilized biocompatible mesenchymal stem cell-derived extracellular vesicles as carriers loaded with the CB2 target medicine AM1241(EVs-AM1241)to protect against neurodegenerative progression and neuronal function in AD model mice.According to the results,EVs-AM1241 were successfully constructed and exhibited better bioavailability and therapeutic effects than bare AM1241.The Morris water maze(MWM)and fear conditioning tests revealed that the learning and memory of EVs-AM1241-treated model mice were significantly improved.In vivo electrophysiological recording of CA1 neurons indicated enhanced response to an auditory conditioned stimulus following fear learning.Immunostaining and Western blot analysis showed that amyloid plaque deposition and amyloidβ(Aβ)-induced neuronal apoptosis were significantly suppressed by EVs-AM1241.Moreover,EVs-AM1241 increased the number of neurons and restored the neuronal cytoskeleton,indicating that they enhanced neuronal regeneration.RNA sequencing revealed that EVs-AM1241 facilitated Aβphagocytosis,promoted neurogenesis and ultimately improved learning and memory through the calcium-Erk signaling pathway.Our study showed that EVs-AM1241 efficiently reversed neurodegenerative pathology and enhanced neurogenesis in modelmice,indicating that they are very promising particles for treating AD.

Imaginary-Time Quantum Relaxation Critical Dynamics with Semi-Ordered Initial States

We explore the imaginary-time relaxation dynamics near quantum critical points with semi-ordered initial states.Different from the case with homogeneous ordered initial states,in which the order parameter M decays homogeneously as M∝τ^(-β/vz),here M depends on the location x,showing rich scaling behaviors.Similar to the classical relaxation dynamics with an initial domain wall in model A,which describes the purely dissipative dynamics,here as the imaginary time evolves,the domain wall expands into an interfacial region with growing size.In the interfacial region,the local order parameter decays as M∝τ^(-β1/vz),withβ_(1)being an additional dynamic critical exponent.Far away from the interfacial region the local order parameter decays as M∝τ-β/vz in the short-time stage,then crosses over to the scaling behavior of M∝τ^(-β1/vz)when the location x is absorbed in the interfacial region.A full scaling form characterizing these scaling properties is developed.The quantum Ising model in both one and two dimensions are taken as examples to verify the scaling theory.In addition,we find that for the quantum Ising model the scaling function is an analytical function andβ_(1)is not an independent exponent.

Cerebral mechanism of puncturing at He-Mu point combination for functional dyspepsia: study protocol for a randomized controlled parallel trial

Acupuncture is widely used to treat functional dyspepsia with satisfactory outcomes. Combination of the He and Mu acupoints is commonly used and has a synergistic effect on functional dyspepsia; however, its underlying mechanisms remain unclear. Therefore, a randomized controlled parallel clinical trial is currently underway at Chengdu University of Traditional Chinese Medicine, China. This trial is designed to explore the efficacy of and central responses to the He-Mu point combination in patients with functional dyspepsia using functional magnetic resonance imaging. A total of 105 patients with functional dyspepsia will be allocated into 3 groups: the low-He point group(puncturing at Zusanli(ST36)), Mu point group(puncturing at Zhongwan(CV12)), and He-Mu point combination group(puncturing at ST36 and CV12). Every participant will receive 20 sessions of manual acupuncture for 4 weeks. The needles will be inserted perpendicularly to a depth of 1 to 2 cun. The angle of rotation and twisting will range from 90 to 180 degrees, while lifting and thrusting will range from 0.3 to 0.5 cm. The various manipulations will be performed 60 to 90 times per minute. The needles will remain in place for 30 minutes, during which manipulation will be applied every 10 minutes. Magnetic resonance imaging will be performed before and after 20 sessions of acupuncture. The primary outcome is symptom improvement according to the Chinese version of the Nepean Dyspepsia Index. Secondary outcomes include the Leeds dyspepsia questionnaire, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Beck Anxiety Inventory, Beck Depression Inventory, and visual analogue scale scores before and after 10 and 20 sessions of acupuncture. Needle sensation and adverse events will be used to assess the therapeutic effects. This study will promote more widespread awareness of the benefits of acupoint combination in the clinical setting and provide a further explanation of the neuromechanism by which acupuncture at the He-Mu point combination for functional dyspepsia. Registration: Chinese Clinical Trial Registry, Chi CTR-IOR-15006402.

The effect of adjuvant chemotherapy in resectable cholangiocarcinoma: A meta-analysis and systematic review

Background: The benefit of adjuvant chemotherapy for resectable cholangiocarcinoma remains unclear due to the lack of randomized control studies. This study aimed to investigate the possible benefit of postoperative adjuvant chemotherapy for resectable cholangiocarcinoma. Data sources: Relevant research articles published before 1 st March 2018 in Pub Med, Embase and the Cochrane library databases were retrieved. Published data were extracted and analyzed by RevMan 5.3, and the results were presented as hazard ratios(HRs) [95% confidence intervals(CI)] and forest plots. Results: One prospective and eighteen retrospective studies were included, with a total number of 11,458 patients, 4696 of whom received postoperative chemotherapy. There was a significant improvement of the overall survival(OS) for patients who underwent operation + adjuvant chemotherapy compared to those who underwent operation alone(HR = 0.61; P < 0.001). Subgroup analyses show that the postoperative chemotherapy group compared with operation alone group are indicated as follows: hilar cholangiocarcinoma group(HR = 0.60; P < 0.001), intrahepatic cholangiocarcinoma group(HR = 0.60; P < 0.001), R1 resection group(HR = 0.71; P = 0.04), LN-positive diagnosis group(HR = 0.58; P < 0.001), gemcitabine-based chemotherapy group(HR = 0.42; P < 0.001), distal cholangiocarcinoma group(HR = 0.48; P = 0.17), R0 resection group(HR = 0.69; P = 0.43), and 5-flurouracil-based chemotherapy group(HR = 0.90; P = 0.66), respectively. Conclusions: Postoperative adjuvant chemotherapy can improve the OS in intrahepatic and hilar cholangiocarcinoma patients. However, distal cholangiocarcinoma patients gain no benefit from postoperative adjuvant chemotherapy. Prospective randomized trials are warranted in order to define the standard chemotherapy regimen.

葡萄籽原花青素调控NLRP3/Caspase-1通路介导的焦亡途径对糖尿病视网膜病变大鼠的保护作用

目的探讨葡萄籽原花青素调控NLRP3/Caspase-1通路介导的焦亡途径对糖尿病视网膜病变(DR)大鼠的保护作用。方法建立DR大鼠模型,随机分为模型组、葡萄籽原花青素组、VX-765组、葡萄籽原花青素+VX-765组(每组各12只),另取12只大鼠为对照组,药物干预14 d,HE染色观察各组大鼠视网膜组织病理学变化;TUNEL染色检测各组大鼠视网膜神经节细胞(RGC)焦亡情况;采用试剂盒测定各组大鼠视网膜组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、活性氧(ROS)、丙二醛(MDA)及血清中炎症因子糖基化终末产物(AGEs)、白细胞介素(IL)-1β与IL-18水平;Western blot检测各组大鼠视网膜组织NLRP3/Caspase-1通路蛋白表达水平。结果与对照组相比,模型组大鼠视网膜组织明显变薄,结构疏松,细胞结构层次紊乱、排列不规则,RGC变少、稀疏,呈现严重病理损伤变化,RGC焦亡率,ROS与MDA水平,AGEs、IL-1β、IL-18水平,NLRP3与Caspase-1蛋白表达水平均显著升高(均为P<0.05),SOD与CAT水平均显著降低(均为P<0.05)。与模型组相比,葡萄籽原花青素组、VX-765组大鼠视网膜组织形态结构得到恢复,病理损伤均有不同程度减轻,RGC焦亡率,ROS与MDA水平,AGEs、IL-1β与IL-18水平,NLRP3与Caspase-1蛋白表达水平均降低(均为P<0.05),SOD与CAT水平均升高(均为P<0.05)。与葡萄籽原花青素组及VX-765组分别相比,葡萄籽原花青素+VX-765组大鼠视网膜组织病理损伤进一步减轻,形态结构几乎恢复正常,RGC焦亡率,ROS与MDA水平,AGEs、IL-1β与IL-18水平,NLRP3与Caspase-1蛋白表达水平均降低(均为P<0.05),SOD与CAT水平均升高(均为P<0.05)。结论葡萄籽原花青素可以抑制炎症发生发展,增强DR大鼠抗氧化活性,减轻过氧化反应,缓解视网膜组织病理学损伤,减少RGC焦亡,可能是通过抑制NLRP3/Caspase-1信号通路实现的。

黄芩苷调节IL-33/ST2信号通路对糖尿病视网膜病变大鼠视网膜新生血管生成的影响

目的探讨黄芩苷调节白细胞介素(IL)-33/基质裂解素2(ST2)信号通路对糖尿病视网膜病变(DR)大鼠视网膜新生血管生成的影响。方法SD大鼠随机分为对照组(正常大鼠,灌胃生理盐水)、DR模型组(大鼠建立DR模型后,灌胃生理盐水)和黄芩苷低、中、高剂量组(大鼠建立DR模型后,分别灌胃75 mg·kg^(-1)、150 mg·kg^(-1)、300 mg·kg^(-1)黄芩苷),所有大鼠均以右眼为实验眼。FFA检查各组大鼠视网膜血管生成情况,ELISA检测各组大鼠血清血管内皮生长因子(VEGF)、Ang-1、IL-6、IL-33、肿瘤坏死因子-α(TNF-α)水平,Western blot检测各组大鼠视网膜组织中IL-33、ST2蛋白表达水平。结果与对照组相比,DR模型组大鼠血清VEGF、Ang-1、IL-6、IL-33、TNF-α水平及视网膜组织中IL-33、ST2蛋白表达水平均显著升高(均为P<0.05),右眼眼底新生血管增多,荧光素渗漏明显;与DR模型组相比,黄芩苷低、中、高剂量组大鼠血清VEGF、Ang-1、IL-6、IL-33、TNF-α水平及视网膜组织中IL-33、ST2蛋白表达水平均显著降低(均为P<0.05),右眼视网膜新生血管生成减少,荧光素渗漏减少;随着黄芩苷剂量的升高,大鼠血清VEGF、Ang-1、IL-6、IL-33、TNF-α水平及视网膜组织中IL-33、ST2蛋白表达水平均逐渐降低(均为P<0.05)。结论黄芩苷能抑制IL-33/ST2信号通路激活,减轻DR大鼠体内炎症水平,减少视网膜新生血管生成。

Technical Analysis of Energy Saving and Emission Reducing in China's Cement Industry Based on LEAP Model

[Objective]The study aimed at evaluating the ability to save energy and reduce CO 2 emission in China's cement industry.[Method] Based on long-term energy alternative planning system software(LEAP)," LEAP of China's cement industry" model was established to simulate energy conservation and emission reduction in China's cement industry from 2010 to 2040 in different technologic situations.[Result]To save energy and reduce CO 2 emissions,new dry process kiln has priority over other technologies or measures,followed by equipment enlargement,mechanical shaft kiln,power generation system based on waste heat,as well as high-efficiency and energy-saving grinding technology,and new preparation technology.If all the advanced technologies and measures are adopted,energy consumption and CO 2 emissions can be reduced by about 40.76% and 42.97% respectively.[Conclusion]LEAP of model is suitable for analyzing energy saving and emission reducing in China's cement industry and other industrial fields.

高效液相色谱法测定防晒类化妆品中邻甲氨基苯甲酸甲酯

建立了一种高效液相色谱法测定防晒类化妆品中邻甲氨基苯甲酸甲酯含量的方法。样品经提取、超声、过滤后,采用Welch Xtimate^(®)C_(18)色谱柱分离,高效液相色谱-二极管阵列检测器进行定性、定量分析。在本实验条件下,邻甲氨基苯甲酸甲酯能与防晒类化妆品中常见的22种防晒剂进行分离,其质量浓度与峰面积之间呈良好的线性关系(r=0.9996),检出限为0.009%,定量限为0.029%,在高、中、低三种质量浓度的添加回收率实验中,回收率在99.33%~111.5%之间,RSD在0.3%~3.0%之间。该方法专属性强、准确度高,适用于防晒类化妆中邻甲氨基苯甲酸甲酯含量的测定。

Restoration of the pre-Jurassic paleogeomorphology and its control on hydrocarbon distribution in western Ordos Basin

In recent years,the discovery of the Jurassic oil reservoirs in the Western Thrust Belt of the Ordos Basin reveals that the Jurassic formation in this area has huge oil and gas potential.The pre-Jurassic paleo-geomorphology plays a vital role in the formation of the Jurassic oil reservoirs.In this paper,the impression method is applied to restore the pre-Jurassic paleogeomorphology of the Hongde area in the western Ordos Basin,using a large number of drilling,logging,well testing and the latest 3D seismic data.The pre-Jurassic paleogeomorphological units in the study area can be categorized into five groups,including ancient channel valley,ancient terrace,slope,interchannel mound,and low residual mound facies.The oil reservoirs are mainly distributed in highland areas such as slope belts and low residual mounds,the main areas where hydrocarbons accumulate.In addition,the branch ditches in the study area are developed to the southeast and merged into the Ganshan ancient channel.The sandstone in the confluence area of the branch gully is well sorted and connected under frequent scouring by the river.The sand bodies of good connectivity therefore form a drainage system for long-term hydrocarbon migration.The formation of the Jurassic reservoirs in the study area is mainly affected by sedimentary facies,deposition location,and hydrocarbon migration pathway(or fault)of pre-Jurassic paleo-morphology.The results from this study can be useful for the prediction of the Jurassic sweet spots in the western margin of the Ordos Basin.

Decay rate of Larix gmelinii coarse woody debris on burned patches in the Greater Khingan Mountains

The decomposition of coarse woody debris(CWD)affects the energy flow and nutrient cycling in forest ecosystems.Previous studies on CWD have focused on the input,decomposition,reserve dynamics,and CWD functions,but coarse woody debris decomposition is complex and the results from different regions vary considerably.It is not clear which factors affect decay rate(k),especially at different decomposition stages.In this study,a single-exponential decay model was used to analyze the characteristics of CWD decomposition in Larix gmelinii forests over the 33 years following a fire in the Greater Khingan Mountains.The results show that the decay rate of coarse woody debris was positively correlated to decay class.The average decomposition rate was 0.019,and 41 years and 176 years are needed for a 50%and 95%mass loss,respectively.CWD nutrient content,density,and water content could explain the variance in the decay rate(~42%)of the decay factors such as amount of leaching,degree of fragmentation,respiration of the debris,and biotransformation,and varied significantly between different decay classes.Using the space-time substitution method,this study arranged the coarse woody debris of different mortality times to form a 33 year chronosequence which revealed the decomposition process.It was concluded that the decay rate was mainly explained by structural component of the debris and its nitrogen and water contents.This paper quantifies the indicators affecting CWD decay to explain the decomposition process.

Self-Similarity Breaking:Anomalous Nonequilibrium Finite-Size Scaling and Finite-Time Scaling

Symmetry breaking plays a pivotal role in modern physics.Although self-similarity is also a symmetry,and appears ubiquitously in nature,a fundamental question arises as to whether self-similarity breaking makes sense or not.Here,by identifying an important type of critical fluctuation,dubbed‘phases fluctuations’,and comparing the numerical results for those with self-similarity and those lacking self-similarity with respect to phases fluctuations,we show that self-similarity can indeed be broken,with significant consequences,at least in nonequilibrium situations.We find that the breaking of self-similarity results in new critical exponents,giving rise to a violation of the well-known finite-size scaling,or the less well-known finite-time scaling,and different leading exponents in either the ordered or the disordered phases of the paradigmatic Ising model on two-or three-dimensional finite lattices,when subject to the simplest nonequilibrium driving of linear heating or cooling through its critical point.This is in stark contrast to identical exponents and different amplitudes in usual critical phenomena.Our results demonstrate how surprising driven nonequilibrium critical phenomena can be.The application of this theory to other classical and quantum phase transitions is also anticipated.

Spatial Distribution of CO2 Concentration over South America during ENSO Episodes by Using GOSAT Data

Carbon dioxide (CO2) is one of the most important greenhouse gases;its concentration and distribution have important implications on climate change. The El Ni?o Southern Oscillation (ENSO) is the Earth’s strongest climate fluctuation on inter-annual time scales and has global impacts. However, to date, there is no research on how ENSO affects the spatial distribution of CO2 concentration. In this study, we used spatial CO2 data from the ENVIronmentSATellite (ENVISAT) and the Greenhouse Gases Observing Satellite (GOSAT), the long duration monthly mean atmospheric CO2 from Mauna Loa Observatory, Multivariate ENSO Index (MEI) from Earth System Research Laboratory to analyze the way that ENSO affects spatial distribution of CO2 concentration in South America, which is affected by ENSO seriously. Our research revealed that monthly CO2 growth rate has a moderate, positive correlation relationship with MEI. We used geostatistics to predict and simulate the spatial distribution of CO2 and found that in south of 12°S, CO2 concentration of ENSO warm episode is lower than the one of ENSO cold and neutral episodes. ENSO impacts CO2 spatial distribution mainly in November, December, January and February;moderate-high concentration zone of ENSO warm episode more concentrates in the northern part of South America.

A new method for predicting injection multiples of extreme displacement in waterflood reservoirs

The theoretical relationship between water injection multiple(i.e.injected pore volume)and water saturation is inferred from theoretical concepts of reservoir engineering.A mathematical model based on core displacement tests is established for the entire injection process that satisfies both initial displacement and extreme displacement,simultaneously.The results show that prior to the flooding,the water injection multiple has a linear relationship with the water saturation,and the utilization rate of the injected water is the highest.As water breakthrough at the production end,the water-cut increases,and the injection multiple increases exponentially while the utilization efficiency of the injected water gradually decreases.When the injection multiple approaches infinity,the utilization efficiency of the injected water gradually decreases to 0,by which time the water-cut at the production end is always 1.At this time,the water saturation no longer changes,and the water flooding recovery rate reaches its limit.Based on the experimental test data,a mathematical model of the entire process of injection multiple and water saturation is established,which has high fitting accuracy that can predict the injection multiple in the different stages of development of a mature oil reservoir.The dynamically changing index of the injection water utilization efficiency in reservoir development by reactive water flooding can be obtained through reasonable transformation of the mathematical model.This is of great significance in guiding evaluations of the effects of reservoir development and formulating countermeasures.

Recent advances in evaluation, evolution and quantitative characterization of tight reservoirs: Introduction

Unconventional resources will significantly add to the petro-leum reserves and their contribution to global gas/oil production is expected to increase to 25%over the next two decades.However,unconventional reservoirs of coal methane,shale gas,tight sand-stone gas and gas hydrate have complex pore structures and are typically tight with porosity and permeability much lower than conventional reservoirs(Pang et al.,2022;Yin et al.,2018a,2018b).The characterization of the pore structure and the study of micro-scale multiphase flow mechanism are extremely impor-tant for the understanding of unconventional reservoirs.Recent studies show that emerging methodologies have become the most powerful in characterizing the dynamics of liquids in porous media from the nano-pore to fracture scale.

Unresolved Excess Accumulation of Myelin-Derived Cholesterol Contributes to Scar Formation after Spinal Cord Injury

Spinal cord injury triggers complex pathological cascades,resulting in destructive tissue damage and incomplete tissue repair.Scar formation is generally considered a barrier for regeneration in the central nervous system.However,the intrinsic mechanism of scar formation after spinal cord injury has not been fully elucidated.Here,we report that excess cholesterol accumulates in phagocytes and is inefficiently removed from spinal cord lesions in young adult mice.Interestingly,we observed that excessive cholesterol also accumulates in injured peripheral nerves but is subsequently removed by reverse cholesteroltransport.Meanwhile,preventing reverse cholesterol transport leads to macrophage accumulation and fibrosis in injured peripheral nerves.Furthermore,the neonatal mouse spinal cord lesions are devoid of myelin-derived lipids and can heal without excess cholesterol accumulation.We found that transplantation of myelin into neonatal lesions disrupts healing with excessive cholesterol accumulation,persistent macrophage activation,and fibrosis.Myelin internalization suppresses macrophage apoptosis mediated by CD5L expression,indicating that myelin-derived cholesterol plays a critical role in impaired wound healing.Taken together,our data suggest that the central nervous system lacks an efficient approach for cholesterol clearance,resulting in excessive accumulation of myelin-derived cholesterol,thereby inducing scar formation after injury.