Brain Functional Network Changes in Patients with Poststroke Cognitive Impairment Following Acupuncture Therapy

Background: The mechanisms by which acupuncture affects poststroke cognitive impairment (PSCI) remain unclear. Objective: To investigate brain functional network (BFN) changes in patients with PSCI after acupuncture therapy. Methods: Twenty-two PSCI patients who underwent acupuncture therapy in our hospital were enrolled as research subjects. Another 14 people matched for age, sex, and education level were included in the normal control (HC) group. All the subjects underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans;the PSCI patients underwent one scan before acupuncture therapy and another after. The network metric difference between PSCI patients and HCs was analyzed via the independent-sample t test, whereas the paired-sample t test was employed to analyze the network metric changes in PSCI patients before vs. after treatment. Results: Small-world network attributes were observed in both groups for sparsities between 0.1 and 0.28. Compared with the HC group, the PSCI group presented significantly lower values for the global topological properties (γ, Cp, and Eloc) of the brain;significantly greater values for the nodal attributes of betweenness centrality in the CUN. L and the HES. R, degree centrality in the SFGdor. L, PCG. L, IPL. L, and HES. R, and nodal local efficiency in the ORBsup. R, ORBsupmed. R, DCG. L, SMG. R, and TPOsup. L;and decreased degree centrality in the MFG. R, IFGoperc. R, and SOG. R. After treatment, PSCI patients presented increased degree centrality in the LING.L, LING.R, and IOG. L and nodal local efficiency in PHG. L, IOG. R, FFG. L, and the HES. L, and decreased betweenness centrality in the PCG. L and CUN. L, degree centrality in the ORBsupmed. R, and nodal local efficiency in ANG. R. Conclusion: Cognitive decline in PSCI patients may be related to BFN disorders;acupuncture therapy may modulate the topological properties of the BFNs of PSCI patients.

合水油田含聚合物采出水处理技术的研究与应用

长庆合水油田采出水废水中含有大量的聚合物、水凝胶,采出水水体发黑、黏度大、乳化稳定性强、难破乳,难以用常规污水处理方法进行处理。在对水质成份进行详细分析后,认为水体发黑的原因是其中的二价铁离子与硫化物形成了黑色的硫化铁胶体固形物。用“氧化→解聚→絮凝”新工艺对合水油田采出水进行处理,效果十分显著。首先对含聚水中聚合物氧化解聚,破坏其结构稳定性,然后用适量的过碳酸钠(SPC)使硫化铁胶体脱色,随后再进行絮凝沉淀,使用200~350ppm的SPC和2~5ppm的阳离子聚丙烯酰胺和聚合硫酸铁组合的复合絮凝剂,可以使含聚采出水的悬浮物下降到30mg·L^(-1)以下,pH约为7.0,且有效降低了水体的色度和浊度,其中浊度降低率达到98.02%,铁离子去除率为96.46%。较好地解决了含聚废水水体发黑、不易沉降、难处理等问题,有效改善了采出水水质,达到回注要求。

Decoding molecular mechanisms:brain aging and Alzheimer's disease

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's disease.Beyond these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging brain.Understanding these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect cognition.This review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements

In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were performed.Two projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 g.The onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and analysed.Uniaxial compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching process.During the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant grain.The calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were observed.The dynamic mechanical response process of the dummy propellant grain was analysed in detail.The results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.

Isoindigo nanoparticles for photoacoustic imaging-guided tumor photothermal therapy

The key factor in photothermal therapy lies in the selection of photothermal agents.Traditional photothermal agents generally have problems such as poor photothermal stability and low photothermal conversion efficiency.Herein,we have designed and synthesized an isoindigo(IID)dye.We used isoindigo as the molecular center and introduced common triphenylamine and methoxy groups as rotors.In order to improve the photothermal stability and tumor targeting ability,we encapsulated IID into nanoparticles.As a result,the nanoparticles exhibited high photothermal stability and photothermal conversion efficiency(67%)upon 635 nm laser irradiation.Thus,the nanoparticles demonstrated a significant inhibitory effect on live tumors in photothermal therapy guided by photoacoustic imaging and provided a viable strategy to overcome the treatment challenges.

Microscopic Analysis of Cementitious Sand and Gravel Damming Materia

The mechanical properties of cementitious sand and gravel damming material have been experimentally determined by means of microscopic SEM(Scanning Electron Microscopy)image analysis.The results show that the combination of fly ash and water can fill the voids in cemented sand and gravel test blocks because of the presence of hydrated calcium silicate and other substances;thereby,the compactness and mechanical properties of these materials can be greatly improved.For every 10 kg/m^(3) increase in the amount of cementitious material,the density increases by about 2%,and the water content decreases by 0.2%.The amount of cementitious material used in the sand and gravel in these tests was 80-110 kg/m^(3),the water-binder ratio was 1-1.50.Moreover,the splitting tensile strength was 1/10 of the compressive strength,and the maximum strength was 7.42 MPa at 90 d.The optimal mix ratio has been found to be 50 kg of cement,60 kg of fly ash and 120 kg of water(C50F60W120).The related dry density was 2.6 g/cm^(3),the water content was 6%,and the water-binder ratio was 1.09.

Analysis of risk factors for postpartum depression after cesarean section in women with early-onset preeclampsia

BACKGROUND Early-onset preeclampsia significantly increases maternal and fetal morbidity and mortality.Many pregnant women with early onset preeclampsia choose cesarean section as their delivery method.Although extensive research has explored the association between postpartum depression(PPD)and cesarean section,few studies have investigated the risk factors after cesarean section in women with early-onset preeclampsia.AIM To examine these risk factors through a retrospective,observational analysis of 287 women who underwent a cesarean section for early preeclampsia between June 2014 and March 2024.METHODS Participants were assessed in person during the 32nd week of pregnancy,2 days post-cesarean,and 6 weeks postpartum.According to the Edinburgh Postnatal Depression Scale(EPDS),participants who underwent cesarean section were divided into PPD(n=60)and non-PPD groups(n=227).Furthermore,PPD was diagnosed at 6 weeks postpartum according to depressive symptoms(EPDS score≥11).The demographic and clinical features of PPD were screened.Multivariate logistic regression analysis was used to identify PPD risk factors.RESULTS The prevalence of PPD was 20.9%(60/287)among the 287 women who underwent cesarean section for early-onset preeclampsia.Multivariate logistic regression analyses revealed that advanced age(age>40 years)[odds ratio(OR)=1.93,95%CI:1.31-2.82],previous preeclampsia(OR=7.15,95%CI:5.81-8.85),pre-pregnancy obesity(OR=2.42,95%CI:1.62-3.63),gestational diabetes mellitus(OR=3.52,95%CI:2.51-4.92),preexisting hypertension(OR=1.35,95%CI:1.03-1.89),PPD symptoms(EPDS≥11)at 2 days postpartum(OR=6.15,95%CI:1.32-28.35),high prenatal self-rating anxiety scale score(OR=1.13,95%CI:1.06-1.18),and pain at 6 weeks postpartum(OR=2.16,95%CI:1.28-3.66)were independently associated with PPD.CONCLUSION Risk factors for PPD after cesarean section in women with early-onset preeclampsia include advanced age(age>40 years),pre-pregnancy obesity,previous preeclampsia,gestational diabetes mellitus,preexisting hypertension,PPD symptoms(EPDS≥11)at 2 days postpartum,prenatal anxiety,and pain at 6 weeks postpartum.The early identi-fication of these factors and interventions can mitigate the risk of PPD.

Intravoxel Incoherent Motion Diffusion Weighted Imaging for the Therapeutic Response of Transarterial Chemoembolization for Hepatocellular Carcinoma

Background: Intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) can not only observe the diffusion of tissue water molecules but also reflect the blood perfusion information of tissue microcirculation. IVIM-DWI has been applied in many clinical areas. However, few studies have addressed the use of IVIM-DWI for the evaluation of transarterial chemoembolization (TACE) response in hepatocellular carcinoma (HCC) patients. Objectives: The purpose of the present study was to explore the role of IVIM-DWI for the therapeutic response of TACE for HCC. Materials and Methods: Twenty patients underwent IVIM-DWI scan on a 3.0T magnetic resonance imaging instrument 1 - 3 days before and 30 to 40 days after TACE. The values of IVIM-DWI parameters, including standard apparent diffusion coefficient (ADC), pure diffusion coefficient (Dslow), pseudo-diffusion coefficient (Dfast) and perfusion fraction (f) were measured. The values of IVIM-DWI parameters before and after TACE were compared using paired t tests. The values between responsive and non-responsive groups were compared using independent-samples t test. P 0.05 indicated statistical significance. Results: After TACE, the ADC and Dslow values in the tumors increased significantly, and the values of Dfast decreased significantly, while the values of f value did not change obviously. The ADC values in responsive group were remarkably higher than those in non-responsive group, the Dfast values in responsive group were significantly lower than those in non-responsive group, but the values of Dslow and f between the two groups were not different significantly. Conclusions: IVIM-DWI parameters can be used as potential markers for the therapeutic response of TACE for HCC.

Symmetry Transformations and Exact Solutions of a Generalized Hyperelastic Rod Equation

In this paper,a nonlinear wave equation with variable coefficients is studied,interestingly,this equation can be used to describe the travelling waves propagating along the circular rod composed of a general compressible hyperelastic material with variable cross-sections and variable material densities.With the aid of Lou’s direct method1,the nonlinear wave equation with variable coefficients is reduced and two sets of symmetry transformations and exact solutions of the nonlinear wave equation are obtained.The corresponding numerical examples of exact solutions are presented by using different coefficients.Particularly,while the variable coefficients are taken as some special constants,the nonlinear wave equation with variable coefficients reduces to the one with constant coefficients,which can be used to describe the propagation of the travelling waves in general cylindrical rods composed of generally hyperelastic materials.Using the same method to solve the nonlinear wave equation,the validity and rationality of this method are verified.

Discovery of hydrocarbon source rocks in the Permian Xinxing Formation in the southern Zhangguangcai range,Northeast China

1.Objective The study area is located at the southern Zhangguangcai range,which is thought to be the eastern part of the Central Asian Orogenic Belt(CAOB).The study area is closed to the eastern margin of the Songliao basin(Fig.1a).No petroleum exploration or related research work have been conducted in this area by far.Based on our most recent geological mapping,numerous hydrocarbon source rocks were firstly discovered within the Xinxing Formation,which is widely exposed from the central Jilin Province to the southeastern Heilongjiang province.The Xinxing Formation covers an area of nearly 1000 km2 with a total thickness of more than 1481 m(Regional Geology of Heilongjiang Province,1993).Therefore,the Xinxing Formation has huge potential to form oil and gas resources.This new discovery of hydrocarbon source rocks within the Xinxing Formation could provide critical clues for oil and gas resources’investigation in Northeast China,also may has important economic significance.

Synthesis of ordered hierarchically mesoporous/microporous carbon materials via compressed CO_(2) for fructose-to-HMF transformation

Well-ordered hierarchically mesoporous/microporous carbon materials have been successfully fabricated by using dual soft-templating approach through compressed CO_(2).Pluronic F127 and different type of surfactants,including nonionic,cationic,and anionic surfactants,were used as dual templates to investigate the influence on the morphology and nanostructure of the as-prepared carbon samples.TEM,SEM,N2 sorption,wide-angle and small-angle XRD analysis were employed to reveal the well-ordered hierarchically micro-mesoporous structure with2 D hexagonal symmetry by using compressed CO_(2).The prepared HPC samples with different pressures as the catalyst carriers have been functioned by chlorosulfonic acid for the fructose conversion into HMF.Chlorosulfonic acid concentration,catalyst dosage and reaction temperature have been optimized for fructose-to-HMF transformation with the obtained catalyst.The performances of as-made HPC-SO_(3) H samples in HMF yield and reaction rate of fructose-to-HMF transformation have been investigated.The stability of the samples was also conducted in the dehydration of fructose to HMF for five cycles.The possible catalytic mechanism by using hierarchically porous carbon materials as catalyst support for fructose-to-HMF transformation was proposed.

Partial pore blockage and polymer chain rigidification phenomena in PEO/ZIF-8 mixed matrix membranes synthesized by in situ polymerization

Nanostructured zeolitic imidazolate frameworks(ZIF-8) was incorporated into the mixture of poly(ethylene glycol) methyl ether acrylate(PEGMEA) and pentaerythritol triacrylate(PETA) to synthesize mixed matrix membranes(MMMs) by in situ polymerization for CO_2/CH_4 separation. The solvent-free polymerization between PEGMEA and PETA was induced by UV light with 1-hydroxylcyclohexyl phenyl ketone as initiator. The chemical structural characterization was performed by Fourier transform infrared spectroscopy. The morphology was characterized by scanning electron microscope. The average chain-to-chain distance of the polymer chains in MMMs was investigated by X-ray diffraction. The thermal property was evaluated by differential scanning calorimetry. The CH_4 and CO_2 gas transport properties of MMMs are reported. The relationship between gas permeation–separation performances or physical properties and ZIF-8 loading is also discussed. However, the permeation–separation performance was not improved in Robeson upper bound plot compared with original polymer membrane as predicted. The significant partial pore blockage and polymer rigidification effect around the ZIFs confirmed by the increase in glass temperature and the decrease in the d-spacing, were mainly responsible for the failure in performance improvement, which offset the high diffusion induced by porous ZIF-8.

Molecular dynamics simulation studies of transmembrane transport of chemical components in Chinese herbs and the function of platycodin D in a biological membrane

Objective:To study the transmembrane transport of chemical components of Chinese herbs and to explore the function of platycodin D (PD) on biomembranes.Methods:Interaction between PD and the dipalmitoylphosphatidylcholine (DPPC) bilayer was reproduced by molecular dynamics simulation with the Martini force field.A model validation and methodological study were first performed,and were based on simulation investigations of transmembrane transport for three herbal compounds with distinct hydrophilic properties.Results:PD increased the mobility of the DPPC bilayer since its aglycone strongly interacted with the hydrophobic layer,which broke the structure of the gate layer,and weakened the ordered performance of hydrophobic tails.Conclusion:The Martini force field was successfully applied to the study of the interaction between herbal compounds and a biological membrane.By combining the dynamics equilibrium morphology,the distribution of drugs inside and outside the biomembrane,and the interaction sites of drugs on the DPPC bilayer,factors influencing transmembrane transport of drugs were elucidated and the function of platycodin D in a biological membrane was reproduced.

Molecular hallmarks of long non-coding RNAs in aging and its significant effect on aging-associated diseases

Aging is linked to the deterioration of many physical and cognitive abilities and is the leading risk factor for Alzheimer’s disease. The growing aging population is a significant healthcare problem globally that researchers must investigate to better understand the underlying aging processes. Advances in microarrays and sequencing techniques have resulted in deeper analyses of diverse essential genomes(e.g., mouse, human, and rat) and their corresponding cell types, their organ-specific transcriptomes, and the tissue involved in aging. Traditional gene controllers such as DNA-and RNA-binding proteins significantly influence such programs, causing the need to sort out long non-coding RNAs, a new class of powerful gene regulatory elements. However, their functional significance in the aging process and senescence has yet to be investigated and identified. Several recent researchers have associated the initiation and development of senescence and aging in mammals with several well-reported and novel long non-coding RNAs. In this review article, we identified and analyzed the evolving functions of long non-coding RNAs in cellular processes, including cellular senescence, aging, and age-related pathogenesis, which are the major hallmarks of long non-coding RNAs in aging.

Carcinoembryonic antigen,carbohydrate antigen 199 and carbohydrate antigen 724 in gastric cancer and their relationship with clinical prognosis

BACKGROUND Gastric cancer(GC)is a common malignant tumor of the digestive system with a high degree of malignancy.It usually develops insidiously without any specific symptoms in the early stages.As one of the diseases caused by abnormal gene changes,GC has abnormal expression of various oncogenes and products during its development.Tumor markers such as carcinoembryonic antigen(CEA),carbohydrate antigen 199(CA199)and carbohydrate antigen 724(CA724)are not expressed or lowly expressed in normal people,but significantly increased after carcinogenesis.Monitoring the changes in the levels of tumor markers such as CEA,CA199 and CA724 is conducive to early diagnosis and evaluation of the occurrence of some solid tumors.AIM To investigate the expression of CEA,CA199 and CA724 in GC and their correlation with clinical features,hoping to provide more effective markers for the early preventive diagnosis of GC.METHODS Of 87 patients with GC admitted to our hospital from September 2020 to December 2021 were included in the GC group,and another 80 healthy people who came to our hospital for physical examination with normal results during the same period were selected as the control group.The serum CEA,CA199,and CA724 levels were compared between the two groups,and the serum CEA,CA199,and CA724 levels were compared in patients with GC at different TNM stages,and the differences in the positive rates of CEA,CA199,and CA724 alone and in combination in detecting TNM stages of GC and GC were compared.In addition,the relationship between the levels of tumor markers CEA,CA199 and CA724 and the clinicopathological characteristics of GC patients was also analyzed.The relationship between the serum levels of CEA,CA199 and CA724 and the survival period of GC patients was analyzed by Pearson.RESULTS The serum levels of CEA,CA199 and CA724 in GC group were significantly higher than those in control group(P<0.05).With the increase of TNM stage,the serum CEA,CA199 and CA724 expression levels in GC patients increased significantly,and the differences between groups were statistically significant(P<0.05).The positive rate of the CA724 single test was higher than that of CEA and CA199 single test(P<0.05).The positive rate of the three combined tests was 95.40%(83/87),which was higher than that of CEA,CA199 and CA724 single tests.The difference was statistically significant(P<0.05).The combined detection positive rates of CEA,CA199,and CA724 in stages I,II,III,and IV of GC were 89.66%,93.10%,98.85%,and 100.00%respectively,all of which were higher than the individual detection rates of CEA,CA199,and CA724.The differences were statistically significant(P<0.05).There was no significant difference in serum CEA,CA199 and CA724 levels between GC patients with different genders,smoking history and alcohol history(P>0.05).However,the serum CEA,CA199 and CA724 levels were significantly higher in GC patients aged≥45 years,TNM stage III-IV,with lymph node metastasis and tumor diameter≥5 cm than in GC patients aged<45 years,TNM stage I-II,without lymph node metastasis and tumor diameter<5 cm(P<0.05).CONCLUSION The expression levels of serum tumor markers CEA,CA199 and CA724 in patients with GC are high and rise with the increase of TNM stage.The levels of CEA,CA199 and CA724 are related to age,TNM stage,lymph node metastasis and tumor diameter.The combined detection of CEA,CA199 and CA724 is helpful to improve the diagnostic accuracy of GC with high clinical guidance value.

直流故障下MMC-HVDC的两段式限流保护策略

如何对直流故障电流进行有效抑制是实现柔性直流电网大规模发展的关键。为此,研究模块化多电平变换器(modular multilevel converter,MMC)的控制方法,提出一种针对半桥型MMC的两段式限流保护策略,通过减少子模块的投入数目来降低换流站直流出口电压,达到限制短路电流的目的。首先,介绍MMC的拓扑结构及基于MMC的高压直流输电(MMC based high voltage direct current,MMC-HVDC)系统控制策略;其次,分析两段式限流保护策略的原理与直流故障电流特性,介绍MMC-HVDC系统的直流故障保护策略;最后,通过双端MMC-HVDC系统仿真实验,对所提限流保护策略的有效性进行验证。仿真结果表明,两段式限流保护策略可以有效降低断路器开断电流和吸收能量,节约成本。

“Three‐in‐one”strategy:Heat regulation and conversion enhancement of a multifunctional separator for safer lithium-sulfur batteries

The safety problems encountered with lithium–sulfur batteries(LSBs)hinder their development for practical applications.Herein,a highly thermally conductive separator was constructed by cross‐weaving super‐aligned carbon nanotubes(SA‐C)on super‐aligned boron nitride@carbon nanotubes(SA‐BC)to create a composite film(SA‐BC/SA‐C).This separator was used to fabricate safe LSBs with improved electrochemical performance.The highly aligned separator structure created a uniform thermal field that could rapidly dissipate heat accumulated during continuous operation due to internal resistance,which prevented the development of extremely high temperatures.The array of boron nitride nanosheets endowed the composite separator with a large number of adsorption sites,while the highly graphitized carbon nanotube skeleton accelerated the catalytic conversion of high‐valence polysulfides into low‐valence polysulfides.The arrayed molecular brush design enabled the regulation of local current density and ion flux,and considerably alleviated the growth of lithium dendrites,thus promoting the smooth deposition of Li metal.Consequently,a battery constructed with the SA‐BC/SA‐C separator showed a good discharge capacity of 685.2 mAh g−1 over 300 cycles(a capacity decay of 0.026%per cycle)at 2 C and 60°C.This“three‐in‐one”multifunctional separator design strategy constitutes a new path forward for overcoming the safety problems of LSBs.

Evolutionary game-based optimization of green certificate-carbon emission right-electricity joint market for thermal-wind-photovoltaic power system

With the increasing proportion of renewable energy in the power market,the demands on government financial subsidies are gradually increasing.Thus,a joint green certificate-carbon emission right-electricity multi-market trading process is proposed to study the market-based strategy for renewable energy.Considering the commodity characteristics of green certificates and carbon emission rights,the dynamic cost models of green certificates and carbon rights are constructed based on the Rubinstein game and ladder pricing models.Furthermore,considering the irrational bidding behavior of energy suppliers in the actual electricity market,an evolutionary game based multi-market bidding optimization model is presented.Subsequently,it is solved using a composite differential evolutionary algorithm.Finally,the case study results reveal that the proposed model can increase profits and the consumption rate of renewable energy and reduce carbon emission.

哈长柄叶蝉种团一新种及分种检索表(半翅目:叶蝉科:小叶蝉亚科)

哈长柄叶蝉种团Alebroideshaculusgroup此前仅知3种,分布于印度及印度尼西亚。本文记述采自中国陕西及云南的该种团1新种:拟羡长柄叶蝉Alebroides paraxanthus sp.nov.,提供了新种的成虫外部形态及雄性外生殖器特征图。文中还提供了该种团的分种检索表。

Intensified shape selectivity and alkylation reaction for the two-step conversion of methanol aromatization to p-xylene

Two-step conversion of methanol to aromatics via light hydrocarbons can significantly improve the conversion stability compared with direct aromatization of methanol,but it remains a challenge to achieve a high p-xylene(PX)selectivity.Herein,silica coating was firstly used to passivate external acid sites of ZSM-5 catalyst for the aromatization of light hydrocarbons by the chemical liquid deposition method.With the increase of SiO_(2) deposition,the density of the external acid sites of the catalyst was decreased from 0.1 to 0.03 mmol·g^(-1),which inhibited the surface secondary reactions and increased the PX/X from 34.6% to 60.0%.In view of the fact that the aromatization process in the second step was partly inhibited as methanol was consumed in advance in the upper methanol-to-light hydrocarbons catalyst layer,part of methanol was directly introduced into the lower aromatization catalyst layer to promote the alkylation process during the aromatization,which decreased the toluene selectivity from 34.5% to 14.3% but increased the xylene selectivity from 40.0%to 55.3%.It was also found that an appropriate external acid density was needed for aromatization catalyst to strengthen the alkylation process and improve the selectivity of xylene under the conditions of methanol introduction.