Dealuminated Hβ zeolite for selective conversion of fructose to furfural and formic acid

The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at433 K for 1 h in the γ-butyrolactone(GBL)-H_(2)O system, as well as the concomitant formation of 83.0% formic acid. The^(13)C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose.

Sodium butyrate alleviates fructose-induced non-alcoholic fatty liver disease by remodeling gut microbiota to promoteγ-amino butyric acid production

Sodium butyrate(NaB)can regulate lipid metabolism and inhibit hepatic steatosis.This study aimed to investigate whether NaB can alleviate fructose-induced hepat ic steatosis via remodeling the gut microbiota and evaluate the anti-fatty liver mechanisms.The results showed that NaB and NaB-remodeled gut microbiota significantly alleviated fructose-induced hepatic steatosis and increased plasma uric acid and fructose levels.Furthermore,both NaB and NaB-remodeled gut microbiota increased the abundance of Lactobacillus and altered the levels of plasma amino acids(upregulating gamma-amino butyric acid(GABA)and downregulating L-glutamic acid and L-arginine)in fructose-exposed mice.The correlation analysis showed that GABA levels positively correlated with Lactobacillus abundance,and increased GABA levels might promote the reduction of the hepatic triglyceride content.Further studies confirmed that GABA significantly reduced lipid deposition in mouse hepatocytes induced via fructose pretreatment in vitro.These findings suggested that NaB could ameliorate fructose-induced hepatic steatosis by regulating gut microbiota.

Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds

Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction conditions.Here,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal method.Remarkably,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction conditions.The yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO.

Effects of different doses of glucose and fructose on central metabolic pathways and intercellular wireless communication networks in humans

Fructose and glucose are often widely used in food processing and may contribute to many metabolic diseases.To observe the effects of different doses of glucose and fructose on human metabolism and cellular communication,volunteers were given low,medium,and high doses of glucose and fructose.Serum cytokines,glucose,lactate,nicotinamide adenine dinucleotide(NADH)and metabolic enzymes were assayed,and central carbon metabolic pathway networks and cytokine communication networks were constructed.The results showed that the glucose and fructose groups basically maintained the trend of decreasing catabolism and increasing anabolism with increasing dose.Compared with glucose,low-dose fructose decreased catabolism and increased anabolism,significantly enhanced the expression of the inflammatory cytokine interferon-γ(IFN-γ),macrophage-derived chemokine(MDC),induced protein-10(IP-10),and eotaxin,and significantly reduced the activity of isocitrate dehydrogenase(ICDH)and pyruvate dehydrogenase complexes(PDHC).Both medium and high doses of fructose increase catabolism and anabolism,and there are more cytokines and enzymes with significant changes.Furthermore,multiple cytokines and enzymes show strong relevance to metabolic regulation by altering the transcription and expression of enzymes in central carbon metabolic pathways.Therefore,excessive intake of fructose should be reduced to avoid excessive inflammatory responses,allergic reactions and autoimmune diseases.

Determination of Carbon and Nitrogen Isotope Fractions in Tartaric Acid, Oxalic Acid, Glucose and Fructose—National Center of High Technologies of Georgia

Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetables, and fruits. Understanding the isotopic compositions in organic compounds is crucial for comprehending various biochemical processes and the nature of substances present in different natural products. Tartaric acid, oxalic acid, glucose, and fructose are widely distributed compounds, including in vegetables and fruits. Tartaric acid plays a significant role in determining the quality and taste properties of wine, while oxalic acid is also prevalent but holds great interest for further research, especially in terms of carbon isotopic composition. We can unveil the mechanisms of processes that were previously impossible to study. Glucose and fructose are the most common monosaccharides in the hexose group, and both are found in fruits, with sweeter fruits containing higher amounts of these substances. In addition to fruits, wheat, barley, rye, onions, garlic, lentils, peppers, dried fruits, beans, broccoli, cabbage, tomatoes, and other foods are also rich sources of fructose and glucose. To determine the mass fraction of the carbon-13 isotope in these compounds, it is important to study their changes during natural synthesis. These compounds can be modified with a carbon center. According to the existing isotopic analysis method, these compounds are converted into carbon oxide or dioxide [1]. At this point, the average carbon content in the given compound is determined, but information about isotope-modified centers is lost. Dilution may occur through the transfer of other carbon-containing organic compounds in the sample or by dilution with natural carbon or carbon dioxide during the transfer process. This article discusses the possibility of carbon-13 isotope propagation directly in these compounds, both completely modified and modified with individual carbon centers. The literature provides information on determining carbon-13 substance in organic compounds, both with a general approach and for individual compounds [2] [3].

Assessing the impact of concurrent high-fructose and highsaturated fat diets on pediatric metabolic syndrome:A review

High-saturated fat(HF)or high-fructose(HFr)consumption in children predispose them to metabolic syndrome(MetS).In rodent models of MetS,diets containing individually HF or HFr lead to a variable degree of MetS.Nevertheless,simultaneous intake of HF plus HFr have synergistic effects,worsening MetS outcomes.In children,the effects of HF or HFr intake usually have been addressed individually.Therefore,we have reviewed the outcomes of HF or HFr diets in children,and we compare them with the effects reported in rodents.In humans,HFr intake causes increased lipogenesis,hypertriglyceridemia,obesity and insulin resistance.On the other hand,HF diets promote low grade-inflammation,obesity,insulin resistance.Despite the deleterious effects of simultaneous HF plus HFr intake on MetS development in rodents,there is little information about the combined effects of HF plus HFr intake in children.The aim of this review is to warn about this issue,as individually addressing the effects produced by HF or HFr may underestimate the severity of the outcomes of Western diet intake in the pediatric population.We consider that this is an alarming issue that needs to be assessed,as the simultaneous intake of HF plus HFr is common on fast food menus.

科宝500和AA白羽肉鸡生产性能比较分析

文章旨在探讨科宝500和爱拔益加(AA)白羽肉鸡生产性能的差异。试验以科宝500和爱拔益加(AA)白羽肉鸡为研究对象,测定1~6周龄两个品种的平均采食量、平均体重、平均日增重、料重比、死淘率以及欧洲效益指数,分析比较两品种间生产性能的差异变化。结果表明:(1)科宝500肉鸡平均采食量前期变化较大,2周龄时显著高于AA肉鸡(P<0.05),但3周龄显著低于AA白羽肉鸡(P<0.05),整个试验期(1~6周龄),科宝500肉鸡平均采食量高于AA肉鸡,但差异不显著(P>0.05);(2)7和35日龄时,科宝500肉鸡平均体重显著大于AA肉鸡(P<0.05),5周龄时,科宝500肉鸡平均日增重显著高于AA肉鸡(P<0.05),而其他周龄及整个试验期(1~6周龄),科宝500肉鸡平均体重和平均日增重均高于AA肉鸡,但差异均不显著(P>0.05);(3)各周龄及整个试验期(1~6周龄)科宝500肉鸡料重比均低于AA肉鸡,但差异均不显著(P>0.05);(4)4周龄时,科宝500肉鸡死淘率显著高于AA肉鸡(P<0.05),而其他周龄及整个试验期(1~6周龄),科宝500肉鸡死淘率高于AA肉鸡,但差异均不显著(P>0.05);(5)欧洲效益指数(EPI)方面,科宝500肉鸡高于AA肉鸡,但差异不显著(P>0.05)。综合分析,科宝500肉鸡生产性能及养殖效益优于AA肉鸡。

Exposure to Electromagnetic Fields from Mobile Phones and Fructose consumption Coalesce to Perturb Metabolic Regulators AMPK/SIRT1-UCP2/FOXO1 in Growing Rats

Objective In this study,the combined effect of two stressors,namely,electromagnetic fields(EMFs)from mobile phones and fructose consumption,on hypothalamic and hepatic master metabolic regulators of the AMPK/SIRT1-UCP2/FOXO1 pathway were elucidated to delineate the underlying molecular mechanisms of insulin resistance.Methods Weaned Wistar rats(28 days old)were divided into 4 groups:Normal,Exposure Only(ExpO),Fructose Only(FruO),and Exposure and Fructose(EF).Each group was provided standard laboratory chow ad libitum for 8 weeks.Additionally,the control groups,namely,the Normal and FruO groups,had unrestricted access to drinking water and fructose solution(15%),respectively.Furthermore,the respective treatment groups,namely,the ExpO and EF groups,received EMF exposure(1,760 MHz,2 h/day x 8 weeks).In early adulthood,mitochondrial function,insulin receptor signaling,and oxidative stress signals in hypothalamic and hepatic tissues were assessed using western blotting and biochemical analysis.Result In the hypothalamic tissue of EF,SIRT1,FOXO 1,p-PI3K,p-AKT,ComplexⅢ,UCP2,MnSOD,and catalase expressions and OXPHOS and GSH activities were significantly decreased(P<0.05)compared to the Normal,ExpO,and FruO groups.In hepatic tissue of EF,the p-AMPKα,SIRT1,FOXO1,IRS1,p-PI3K,ComplexⅠ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,UCP2,and MnSOD expressions and the activity of OXPHOS,SOD,catalase,and GSH were significantly reduced compared to the Normal group(P<0.05).Conclusion The findings suggest that the combination of EMF exposure and fructose consumption during childhood and adolescence in Wistar rats disrupts the closely interlinked and multi-regulated crosstalk of insulin receptor signals,mitochondrial OXPHOS,and the antioxidant defense system in the hypothalamus and liver.

Synthesis of MgO-doped ordered mesoporous carbons by Mg^(2+)-tannin coordination for efficient isomerization of glucose to fructose

In-situ MgO-doped ordered mesoporous carbon(OMC@MgO)was fabricated by formaldehyde-free self-assembly method,in which biomass-derived tannin was used as carbon precursor replacing fossil-based phenolics,Mg^(2+)as both cross-linker and precursor of catalytic sites.Up to~20 wt% MgO could be doped in the carbon skeleton with good dispersion retaining well-ordered mesoporous structures,while more MgO content(35 wt%)led to the failing in the formation of ordered mesoporous structure.The OMC@MgO possessed a high specific surface area(298.8 m^(2) g^(-1)),uniform pore size distribution(4.8 nm)and small crystallite size of MgO(1.73 nm)due to the confinement effect of ordered mesoporous structure.Using OMC@MgO as the heterogeneous catalyst,a maximum fructose yield of 32.4% with a selectivity up to 81.1%was achieved from glucose in water(90℃,60 min),which is much higher than that obtained using the MgO doped active carbon via conventional post-impregnation method(26.5%yield with 58.3% selectivity).Higher reaction temperature(>90℃)resulted in decrease of selectivity due to the formation of humins.The designed OMC@MgO displayed tolerant to high initial glucose concentrations(10 wt%)and could remain good recyclability without significant loss of activity for three cycles.

Hydrothermal conversion of fructose to lactic acid and derivatives:Synergies of metal and acid/base catalysts

With increasing strict regulation on single-use plastics,lactic acid(LA)and alkyl lactates,as essential monomers for bio-degradable polylactic acid(PLA)plastic products,have gained worldwide attention in both academia and industry.While LA is still dominantly produced through fermentation processes from start,chemical synthesis from cellulosic biomass remains a grand challenge,owing to poor selectivity in activating CAH and CAC bonds in sugar molecules.To our best knowledge,recent publications have been focused on hydrothermal conversion of glucose to LA,while this review summarizes the highlights on direct thermal conversion of fructose as starting material to LA and derivatives.In particular,the synergies of metal/metal cations and acid/base catalysts will be critically revised on retro-aldol and dehydration reactions.This work will provide insights into rational design of active and selective catalysts for the production of carboxylic acids from biomass feedstocks.

circMYO9A_006通过翻译蛋白MYO9A-208aa发挥抑制心肌细胞肥大的作用

目的:研究环状RNA MYO9A_006(circMYO9A_006)对心肌细胞肥大表型的调控作用及可能机制。方法:利用腺病毒介导在乳小鼠心室肌细胞(NMVCs)中过表达circMYO9A_006,并以腺病毒介导过表达同样带有绿色荧光蛋白标签的空载体为对照,检测NMVCs中心肌肥大相关蛋白β-肌球蛋白重链(β-MHC)、骨骼肌肌动蛋白α1(ACTA1)和心房钠尿肽(ANP)的表达。建立去氧肾上腺素(PE)诱导的乳大鼠心室肌细胞(NRVCs)肥大模型,通过鬼笔环肽染色检测过表达circMYO9A_006对NRVCs表面积的影响。双萤光素酶报告基因实验检测circMYO9A_006包含的潜在内部核糖体进入位点(IRES)的活性。通过Western blot实验检测circMYO9A_006翻译蛋白MYO9A-208aa及其在细胞内分布情况。分别制备circMYO9A_006-ORF(直接表达MYO9A-208aa)和circMYO9A_006-ATG-mut(不能表达MYO9A-208aa)重组病毒,以空载体病毒和circMYO9A_006重组病毒分别感染NRVCs,检测circMYO9A_006翻译蛋白MYO9A-208aa对心肌细胞肥大表型的特异调节作用。结果:利用腺病毒可在NMVCs中有效介导circMYO9A_006过表达。过表达circMYO9A_006可显著抑制NMVCs中心肌肥大相关蛋白的表达(P<0.01),并显著抑制PE诱导的NRVCs中心肌肥大相关蛋白的表达和细胞表面积的增加(P<0.05)。双萤光素酶报告基因实验结果提示,circMYO9A_006包含的2个IRES均具有活性。Western blot检测结果显示,在NRVCs中过表达circMYO9A_006可翻译预期大小为28 kD的MYO9A-208aa蛋白,并主要分布于细胞质中。过表达MYO9A-208aa和circMYO9A_006可一致地抑制NRVCs心肌肥大相关蛋白表达(P<0.01),并可逆转PE诱导的NRVCs肥大反应(P<0.05);而过表达circMYO9A_006-ATG-mut没有抑制NRVCs肥大的作用。结论:circMYO9A_006通过翻译蛋白MYO9A-208aa发挥抑制心肌细胞肥大的作用。

构式语法框架下清涧方言“圪AA的”状态形容词研究

陕北晋语清涧方言中“圪AA的”状态形容词有180多个且在日常生活中使用频繁,按照构式语法属于四字格构式。形态上,该构式中A可以是形容词、动词和拟声词。“圪AA的”表达式一部分是通过其对应的“A”式“圪A”式、“AA的”式经重叠、加缀等形态变化生成,一部分是通过给“圪AA的”构式填充A后再将其重叠的结果。句法上,该构式可以在句中作谓语、定语、补语和状语,不受单音节否定词修饰,但可以用在“不/没说”含有对比的否定句中。该构式的基本义为描绘性,其语义和语用内涵包括“极致性”语义量值、“消极/负面性”立场态度偏向和“口语性”语体色彩。

日粮中添加琥珀酸对AA肉鸡生产性能和肠道健康的影响

试验旨在探究日粮中添加琥珀酸对AA肉鸡生产性能和肠道健康的影响。选用1日龄健康AA肉鸡240羽,根据体重随机分为4组,每组5个重复,每个重复12羽。对照组饲喂基础日粮,抗生素组在基础日粮中添加15 mg/kg维吉尼亚霉素,低剂量和高剂量琥珀酸组分别在基础日粮中添加1 g/kg和2 g/kg琥珀酸。试验期为42 d(1~21 d和22~42 d)。结果表明:与对照组相比,高剂量琥珀酸能够提高肉鸡全净膛率(P<0.05);与抗生素组相比,低剂量琥珀酸能够提高肉鸡血清尿酸和尿素氮水平(P<0.05);日粮中添加琥珀酸对肉鸡肠道形态结构和盲肠微生物组成影响较小,但与对照组相比,添加低剂量和高剂量琥珀酸具有下调肠道炎症因子基因IL-4 mRNA表达的趋势(P=0.0992和P=0.0728),添加高剂量琥珀酸还上调了IFN-γ mRNA的表达(P<0.05),提示日粮中添加琥珀酸有利于缓解肉鸡肠道炎症,调节免疫力。由此可见,日粮中添加高剂量(2 g/kg)琥珀酸能够促进肉鸡生长发育、缓解肠道炎症、调节免疫力,而添加低剂量(1 g/kg)琥珀酸则可以改善机体氨氮代谢水平。

AA7075-T6铝合金电阻点焊工艺参数优化研究

轻量化结构设计在保证了结构强度的前提下降低了整车质量,减少了能量消耗,成为汽车工业和航空航天的研究重点。本工作通过建立正交实验获取AA7075-T6铝合金的最佳焊接工艺参数。对接头进行拉伸剪切实验、金相观察和显微硬度测试,并对最优参数组合进行数值模拟,以研究焊接工艺参数对接头质量的影响。结果表明:当焊接时间为60 ms、焊接电流为17 kA、电极压力为0.22 MPa时,点焊接头的综合力学性能最好;焊接参数对电阻点焊接头力学性能的影响顺序为焊接时间>焊接电流>电极压力。焊接过程数值模拟得到的熔核尺寸与实验结果一致。焊接过程发生飞溅和熔核存在缩孔缺陷,导致接头的力学性能较差,失效模式为界面断裂。由于焊接过程接头显微组织发生变化,接头显微硬度变化呈“W”形。

玉米和小麦在AA肉鸡和黄羽肉鸡中的能值及养分代谢率评定

试验旨在比较玉米和小麦在AA肉鸡和黄羽肉鸡中的代谢能值及营养物质的表观代谢率,为玉米和小麦饲粮在家禽养殖生产上的应用提供理论基础。试验通过选择同日龄和相近体重的AA肉鸡和黄羽肉鸡分别进行两个代谢试验。同日龄试验:AA肉鸡和黄羽肉鸡在18日龄时分别各选择96羽,共192羽,AA肉鸡和黄羽肉鸡均随机分为玉米日粮和小麦日粮2个处理组,每个处理组8个重复,每个重复6羽。同体重试验;在试验鸡体重均达到600 g左右时分别在AA肉鸡和黄羽肉鸡中各选择96羽,试验设计分组与同日龄试验一致。试验结果表明,玉米在AA肉鸡中的表观代谢能(AME)、氮校正表观代谢能(AMEn)、粗蛋白和粗脂肪的表观代谢率显著高于同体重的黄羽肉鸡(P<0.05),与同日龄黄羽肉鸡相比没有显著差异;小麦在AA肉鸡中的AME、AMEn、粗蛋白和粗脂肪的表观消化率与同日龄和同体重的黄羽肉鸡相比均有提高,其中AME差异显著(P<0.05);AA肉鸡和黄羽肉鸡对玉米和小麦中淀粉的表观消化率没有显著差异(P>0.05)。综上所述,玉米在AA肉鸡中的能值和养分代谢率高于同体重黄羽肉鸡,小麦在AA肉鸡中的能值和养分表观代谢率高于同日龄和同体重的黄羽肉鸡。

基于AA-UNet的肝硬化辅助诊断系统

为准确地提取高频肝脏超声图像中的肝包膜,本文采用注意力门和空洞空间金字塔池化UNet(Attention gates and Atrous spatial pyramidal pooling UNet,AA-UNet)分割算法,对高频肝脏超声图像中的肝包膜进行识别,并根据肝包膜的物理形状判断肝硬化程度。首先,将数据增强后的高频肝脏超声图像送入网络模型进行训练;其次,将训练好的模型部署到肝硬化辅助诊断系统。实验结果表明,肝硬化辅助诊断系统能有效识别肝包膜区域并判断肝硬化程度。

AA2024铝合金板料敲击式渐进成形性能研究

为了探究合适的数控渐进成形工艺参数范围,确定更优的敲击式渐进成形性能方案,通过单因素试验法研究振幅、频率、工具头直径和层进给量4个因素对AA2024铝合金板料成形性能的影响规律。试验结果表明:与传统的增量成形方式相比,敲击式渐进成形方式会降低板料的成形极限角,板料的成形性能会有所降低;当振幅为5 mm时,成形极限角随着频率的增大而增大;当振幅为10 mm时,成形极限角随着频率的增大而减小,成形随层进给量增大而增大,随层工具头直径增大先减小后增大。

Ywhab通过靶向Hsp90aa1抑制小鼠B细胞淋巴瘤38B9细胞生长

目的:研究Ywhab在小鼠B细胞淋巴瘤发生发展中的作用,并探讨其可能的分子机制。方法:使用生物信息学分析Ywhab与弥漫性大B细胞淋巴瘤(DLBCL)的相关性。在小鼠B细胞淋巴瘤38B9细胞中感染逆转录病毒构建Ywhab基因过表达细胞系,并采用RT-qPCR和Western blot验证Ywhab的mRNA及蛋白(14-3-3β)水平;通过细胞计数法、CCK-8法和小鼠皮下成瘤实验检测Ywhab过表达对38B9细胞在体内外生长的影响;RT-qPCR和Western blot检测细胞凋亡相关蛋白的表达;应用蛋白质免疫共沉淀联合蛋白质谱(CoIP-MS)筛选与14-3-3β特异性结合的蛋白并采用Western blot及分子对接分析进行验证。结果:Ywhab基因在DLBCL中低表达,其低表达预示DLBCL患者的临床预后较差。与正常小鼠骨髓B细胞相比,Ywhab在38B9细胞中低表达。Ywhab过表达能在体内外诱导38B9细胞凋亡,促进凋亡蛋白Puma、Noxa和Bax的mRNA及蛋白表达,抑制抗凋亡蛋白Bcl2的mRNA及蛋白表达(P<0.05)。14-3-3β蛋白能特异性结合Hsp90aa1蛋白并抑制其表达,从而促进38B9细胞凋亡。结论:Ywhab能够显著诱导小鼠B细胞淋巴瘤38B9细胞凋亡,其机制可能是通过靶向抑制Hsp90aa1蛋白表达来实现的。

汉日语言AA式名词叠词与数字的搭配考察

汉日语言中都存在大量AA式名词叠词,但有所不同的是像“年年”这样的同形同义词在汉语中可以和数字“一”共起,在日语中却不行。文章通过词典收集语料后,再将语料逐一输入语料库对汉日AA式名词叠词与数字的搭配见考察,发现汉语AA式名词叠词有“只能与数字‘一’搭配”和“可以和所有数字搭配”两种类型,日语AA式与数字搭配的名词叠词有“不能与数字‘一’搭配”和“可以和所有数字搭配”两种类型。并且汉语AA式名词叠词与数字搭配情况更为普遍,搭配上也更具灵活性。

重庆方言AA式名词重叠结构分析

以方言文献、研究专著、重庆方言电视剧等为语料来源,构建重庆方言AA式名词语料库。研究发现,重庆方言AA式名词具有自己的显著特点。首先,基式词类丰富,包括单音节名词、形容词、动词和量词,它们均能通过重叠构成AA式名词。其次,AA式名词既存在着构形重叠,也存在着构词重叠。再次,基式为名词的AA式重叠结构最为常见,表现出较强的造词能力。最后,重庆方言AA式重叠结构的使用源于长期的语言演变,其词汇量会随方言的变化而不断变化。