Pharmacokinetics of Enrofloxacin and Its Metabolite in Carp (Cyprinus carpio) After a Single Oral Administration in Medicated Feed

A precise and reliable analytical method of high performance liquid chromatography-tandem mass spectrometry(HPLCMS/MS)was developed to measure trace levels of enrofloxacin(ENR)and its major metabolite ciprofloxacin(CIP)in carp tissues.Optimized chromatographic separation was obtained on a Waters Xterra MS C_(18) reversed-phase column using gradient elution with methanol and 0.1%formic acid aqueous solution including 5mmolL^(-1) of ammonium acetate.The established method was applied to study the pharmacokinetics and distribution of ENR and CIP in tissues of carp following a single oral administration in feed at a dosage of 40mgkg^(-1) bw(body weight).Data were analyzed using DAS 2.0 dynamics software,and the experimental results suggest that ENR was rapidly absorbed and extensively distributed in carp tissues through systemic circulation,and the pharmacokinetic characteristics can be described with a two-compartment model.The elimination half-lives(t_(1/2β))from muscle,liver,gill,plasma and skin were 131,160,104,132 and 310 h,respectively.The areas under the drug concentration-time curves(AUC)for these tissues were 491,972,750,249 and 706hmgkg^(-1),respectively.The maximum concentration(C_(max))values were 13,29,37,9 and 5mgkg^(-1) with peak times(t_(max))of 8,4,4,2 and 4 h,respectively.Ciprofloxacin,the active metabolite of ENR,was also detected in carp tissues,indicating that only 1.54%of de-ethylation of ENR occurs in carp.At a water temperature of 18℃,the drug withdrawal time was determined to be no less than 24 d while the carp was fed at a single dosage of 40mgkg^(-1).

“物美质优”判断偏差对次优食物浪费的影响--心理机制及应对策略

全球因食物外形缺陷而产生的浪费问题日趋严重,这些外观有缺陷但仍可食用的食物被称为“次优食物”。次优食物浪费根源于消费者的审美偏差,但以往研究较少关注消费者回避次优食物的心理机制,对相关干预措施的有效性探讨不够。本文基于常人信念理论,研究消费者在次优食物购买中的常人信念,并提出“酷化拟人形象”的干预措施。通过四个实验发现,消费者存在“物美质优”信念,即次优食物的低外观水平会降低消费者对次优食物口味与健康的评价,而“酷化拟人形象”可以强化消费者对次优食物的自然性感知,增强消费者的购买意愿,消费者的自主性水平对此效应可产生调节作用。本文厘清了消费者的美学偏见对次优食物感知障碍的影响路径,创新性地提出新型视觉线索,促进消费者形成可持续性食物选择行为,系统地揭示了从食物浪费的认知偏差到视觉助推效应再到助推机制与效应边界的内在机理,为企业提供低成本、易执行的管理工具,有助于解决次优食物滞销问题,也在推动食物可持续发展方面为政府提供了高效率的政策方案。

聚乙烯醇缩丁醛改性膜片研究

聚乙烯醇缩丁醛(PVB)作为安全玻璃中间膜的主要用材,在实际生产中得到了广泛的关注,但是对于安全玻璃而言,提高安全玻璃的整体安全性是推动相关行业发展的重要目标,这就对PVB膜片的综合性能提出了更高的要求。文章介绍了聚乙烯醇缩丁醛膜片的四种改性研究方式,主要有共混改性、原位聚合改性、交联改性和增塑改性,旨在为PVB膜片的改性研究提供更多参考。

基于大核分离和通道先验卷积注意的PCB缺陷检测方法

针对印刷电路板缺陷尺寸微小、形态复杂多样和低区分度导致检测准确率低、漏检率高等问题,提出了一种基于大核分离和通道先验卷积注意的印刷电路板缺陷检测方法。首先,结合多尺度特征提取和空间卷积注意力机制,提出大核分离空间金字塔池化以提升模型的多尺度特征整合能力和建模能力。其次,在Neck网络中构建P2小目标检测层,使模型学习更加丰富且鲁棒的特征表示。引入通道先验卷积注意力模块在通道和空间维度上动态分布注意力权重,保留通道先验的同时有效地提取空间关系,提高模型对小目标缺陷的检测精度。实验结果表明,本文方法在PKU-Market-PCB数据集上的mAP达到了98.6%,比基准模型YOLOv8n提升了3.4%,精确度提升了2.6%,召回率提升了4.6%,单张图像推理时间仅为4.1 ms,适于实时检测。该方法显著提高了印刷电路板缺陷检测的准确率和实时性,具有较高的实际应用价值。

复杂基质环境中长时间维度被动采样装置的研发与评估——以污水管网中精神活性物质的监测为例

精神活性物质(Psychoactive Substance,PAS)的非法滥用是人类发展面临的难题,快速高效地评估毒情是解决这一难题的基础,及时获取时间加权浓度、低成本的被动采样技术日益受到关注。本研究基于混合型阳离子交换树脂吸附剂开发了一种新型被动采样装置,并应用于污水管网中PAS的快速监测。探讨了采样条件对甲基苯丙胺、3,4-亚甲二氧基甲基苯丙胺、氯胺酮、去甲氯胺酮、吗啡和可替宁采样率(Sampling Rates,RS)的影响。结果表明,温度和pH对RS的影响较大,流速和溶解性有机物的影响不明显。温度改变时,6种PAS的RS的平均变化为0.195 L·d^(−1);pH改变时,6种PAS的RS的平均变化为0.171 L·d^(−1);流速改变时,6种PAS的RS的平均变化为0.057 L·d^(−1);溶解性有机物浓度改变时,6种PAS的RS的平均变化为0.094 L·d^(−1)。实验室模拟阳性环境下,采用胶体金法快速检测采样装置洗脱液中的PAS,3次实验结果均呈阳性,验证了该方法的可靠性。

安定组地层渗透性变化下的覆岩白垩系含水层涌水规律研究

为了研究呼吉尔特矿区某深埋矿井煤层开采对地下含水层的影响,采用地下水三维数值模型对大采高深埋煤层开采过程中地下水流场的变化进行模拟研究。模拟结果显示,煤层开采对顶板白垩系含水层及侏罗系直罗组含水层流场均产生较大影响,工作面开采过程中安定组地层渗透系数发生改变,使其隔水性能产生变化,上覆白垩系含水层参与井下涌水程度随之改变,导致工作面涌水量呈阶梯状变化趋势。由于白垩系含水层富水性强于直罗组含水层,白垩系含水层依然是工作面的主要涌水来源,其贡献度达到70.4%。该结果可为呼吉尔特矿区深部大采高煤层的防治水重点提供依据。

涡轮盘榫槽电火花线切割加工质量研究

为了提高涡轮叶盘榫槽电火花加工的材料去除率、几何形状精度,文中采用3种相同直径、不同材质的电极丝,进行电火花线切割GH4169枞树形榫槽的对比实验。采用不同工艺规准下的3道线切割工艺:第一次切割使用较大脉冲能量,加工出外形轮廓;第二次切割消除工件在上次加工中产生的变形,提高工件尺寸精度;第三次切割对工件表面进行精修整,减小工件表面变质层。对加工后榫槽进行材料去除率的计算、几何形状精度和轮廓偏差的测量,分析电火花线切割加工对榫槽加工质量的影响。试验结果表明:在高速线加工下榫槽的材料去除率最高;不同电极丝加工后的榫槽几何形状精度均在要求的0.075 mm之内;线切割加工的榫槽轮廓偏差都在0.030 mm左右,同时采用黄铜丝加工的榫槽轮廓偏差最小。采用电火花线切割工艺加工出的榫槽几何形状精度和加工质量均满足加工要求,显示出该工艺巨大的技术潜力。

Synergetic Bioproduction of Short-Chain Fatty Acids from Waste Activated Sludge Intensified by the Combined Use of Potassium Ferrate and Biosurfactants

The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were explored in this work.Experimental results showed that 0.2 g PF(g TSS)^(-1)(total suspended solid)combined with 0.02 g TS(g TSS)^(-1) could further improve SCFAs’production,and the maximum SCFAs content reached 2008.7 mg COD L^(-1),which is 1.2 and 4.5 times higher than those with PF and TS individually added,respectively,and 5.3 times higher than that of blank WAS on Day 12.In the model substrates experiments,the degradation rates of bovine serum albumin and dextran with combination of PF and TS were 41.3%±0.1% and 48.5%±0.06%,respectively,on Day 3,which are lower than those in blank WAS(with degradation rates of 72.3%±0.5%and 90.3%±0.3%).It was revealed that the oxidative effect of PF and the solubilization of TS caused more organic matters to be dissolved out from WAS,providing a large number of biodegradable substances for subsequent SCFAs production.While WAS pretreated with the combination of PF and TS,the relative abundances of Firmicutes increased from 6.4%(blank)to 38.6%,and that of Proteobacteria decreased from 41.8%(blank)to 21.8%.The combination of PF and TS promoted the hydrolysis process of WAS by enriching Firmicutes,and then increased acetic acid production by inhibiting Proteobacteria that consumed SCFAs.Meanwhile,at the genus level,acidogenesis bacteria(e.g.,Proteiniclasticum and Petrimonas)were enriched whereas SCFAs consuming bacteria(e.g.,Dokdonella)were inhibited.

Occurrence,Spatial Distribution,Sources and Risk Assessment of Per-and Polyfluoroalkyl Substances in Surface Sediments of the Yellow River Delta Wetland

Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence,spatial distribution,potential sources,and ecological risks of PFASs.Twenty-three out of 26 targeted PFASs were detected in surface sediment samples from the YRDW,with totalΣ23PFASs concentrations ranging from 0.23 to 16.30 ng g^(-1) dw and a median value of 2.27 ng g^(-1) dw.Perfluorooctanoic acid(PFOA),perfluorobutanoic acid(PFBA)and perfluorooctanesulfonic acid(PFOS)were the main contaminants.The detection frequency and concentration of perfluoroalkyl carboxylic acids(PFCAs)were higher than those of perfluoroal-kanesulfonic acids(PFSAs),while those of long-chain PFASs were higher than those of short-chain PFASs.The emerging PFASs substitutes were dominated by 6:2 chlorinated polyfluoroalkyl ether sulfonic acid(6:2 Cl-PFESA).The distribution of PFASs is significantly influenced by the total organic carbon content in the sediments.The concentration of PFASs seems to be related to human activities,with high concentration levels of PFASs near locations such as beaches and villages.By using a positive matrix factorization model,the potential sources of PFASs in the region were identified as metal plating mist inhibitor and fluoropolymer manufacturing sources,metal plating industry and firefighting foam and textile treatment sources,and food packaging material sources.The risk assessment indicated that PFASs in YRDW sediments do not pose a significant ecological risk to benthic organisms in the region overall,but PFOA and PFOS exert a low to moderate risk at individual stations.

老年旅游视角下乡村旅游适老化服务优化升级研究

目的:文章基于老年旅游的视角,探究乡村旅游适老化服务的优化升级策略。方法:通过实地调研和老年游客访谈,针对乡村旅游适老化服务出现的诸多问题提出具有可行性的优化升级策略。结果:文章分析发现乡村旅游发展中存在适老化旅游产品数量、层次较少,适老化服务基础配套设施缺乏等问题。结论:优化升级乡村旅游景区的适老化服务,既能够实现乡村旅游的改革创新,又能为老年人提供更优质的康养服务、旅游服务、旅居服务等,助力乡村旅游更好地发展。

基于VIC-3D监测的相似材料模拟导水裂隙带发育规律研究

东胜煤田呼吉尔特矿区煤层厚度大、埋深大,煤层开采导水裂隙带存在超高发育现象。为研究呼吉尔特矿区某深埋矿井煤层开采覆岩裂隙的动态演化规律,采用相似材料模拟试验,模拟过程中采用VIC-3D技术监测采动裂隙的动态发育规律。相似材料模拟显示,导水裂隙带发育高度为88 cm,裂采比为30.8,裂隙带形态呈对称“梯形”;VIC-3D监测结果表明,在裂隙发育处,拉张应变较集中,基于VIC-3D监测的导水裂隙带应变云图形态与裂隙带形态相似,与模拟试验结果相吻合,VIC-3D监测技术能够进一步验证实际开挖中裂隙发育情况。

Determination of Lignin in Marine Sediment Using Alkaline Cupric Oxide Oxidation-Solid Phase Extraction-on-Column Derivatization-Gas Chromatography

Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters （TOMs） in marine environment. Extraction and derivatization of lignin oxidation products （LOPs） are crucial for accurate quantification of lignin in marine sediment. Here we report a modification of the conventional alkaline cupric oxide （CuO） oxidation method, the modification consisting in a solid phase extraction （SPE） and a novel on-column derivatization being employed for better efficiency and reproducibility. In spiking blanks, recoveries with SPE for the LOPs are between 77.84% and 99.57% with relative standard deviations （RSDs） ranging from 0.57% to 8.04% （n=3）, while those with traditional liquid-liquid extraction （LLE） are from 44.52% to 86.16% With RSDs being from 0.53% to 13.14% （n=3）. Moreover, the reproducibility is greatly improved with SPE, with less solvent consumption and shorter processing time. The average efficiency of on-column derivatization for LOPs is 100.8%±0.68%, which is significantly higher than those of in-vial or in-syringe derivatization, thus resulting in still less consumption of derivatizing reagents.Lignin in the surface sediments sampled from the south of Yangtze River estuary, China, was determined with the established method. Recoveries of 72.66% to 85.99% with standard deviation less than 0.01mg/10g dry weight are obtained except for p-hydroxybenzaldehyde. The lignin content ∑8 （produced from 10g dry sediment） in the research area is between 0.231 and 0.587mg. S/V and C/V ratios （1.028 ± 0.433 and 0.192±0.066, respectively） indicate that the TOMs in this region are originated from a mixture of woody and nonwoody angiosperm plants; the high values or （Ad/Al）v suggest that the TOMs has been highly degraded.

Application of Principal Component Analysis(PCA)to the Evaluation and Screening of Multiactivity Fungi

Continued innovation in screening methodologies remains important for the discovery of high-quality multiactive fungi,which have been of great significance to the development of new drugs.Mangrove-derived fungi,which are well recognized as prolific sources of natural products,are worth sustained attention and further study.In this study,118 fungi,which mainly included Aspergillus spp.(34.62%)and Penicillium spp.(15.38%),were isolated from the mangrove ecosystem of the Maowei Sea,and 83.1%of the cultured fungi showed at least one bioactivity in four antibacterial and three antioxidant assays.To accurately evaluate the fungal bioactivities,the fungi with multiple bioactivities were successfully evaluated and screened by principal component analysis(PCA),and this analysis provided a dataset for comparing and selecting multibioactive fungi.Among the 118 mangrove-derived fungi tested in this study,Aspergillus spp.showed the best comprehensive activity.Fungi such as A.clavatonanicus,A.flavipes and A.citrinoterreus,which exhibited high comprehensive bioactivity as determined by the PCA,have great potential in the exploitation of natural products and the development of new drugs.This study demonstrated the first use of PCA as a time-saving,scientific method with a strong ability to evaluate and screen multiactive fungi,which indicated that this method can affect the discovery and development of new drugs.

Migration of Some Elements and Radionuclides across aGranite-Granite Contact Zone: A Natural Analoguefor Safe Disposal of High-Level Radwastes

Abstract Elements and natural radionuclides in the contact zone of two granites with different ages would migrate from one to the other because of the difference in their chemical contents and later water-rock interactions. This migration could serve as an analogue for the near-field process of radwastes in a high-level radwaste deep geological disposal repository.

基于Transformer和多尺度CNN的图像去模糊

卷积神经网络(CNN)单独应用于图像去模糊时感受野受限,Transformer能有效缓解这一问题但计算复杂度随输入图像空间分辨率的增加呈2次方增长。为此,提出一种基于Transformer和多尺度CNN的图像去模糊网络(T-MIMO-UNet)。利用多尺度CNN提取空间特征,并嵌入Transformer全局特性捕获远程像素信息。设计局部增强Transformer模块、局部多头自注意力计算网络和增强前馈网络,采用窗口的方式进行局部逐块多头自注意力计算,通过增加深度可分离卷积层,加强不同窗口之间的信息交互。在GoPro测试数据集上的实验结果表明,T-MIMO-UNet的峰值信噪比相比于MIMO-UNet、DeepDeblur、DeblurGAN、SRN网络分别提升了0.39 dB、2.89 dB、3.42 dB、1.86 dB,参数量相比于MPRNet减少了1/2,能有效解决动态场景下的图像模糊问题。

Optimization of Sample Pretreatment for Determination of Polycyclic Aromatic Hydrocarbons in Estuarine Sediments by Gas Chromatography

This study examined levels of polycyclic aromatic hydrocarbons (PAHs) in estuarine sediments in Licun (Qingdao, China) by gas chromatography under optimized conditions for sample pretreatment via ultrasonic extraction, column chromatography, and thin layer chromatography. Methanol and dichloromethane (DCM)/methanol (2:1, v/v) were used in ultrasonic extraction, and DCM was used as eluate for column chromatography. The developing system consisted of n-hexane and DCM at a ratio of 9:1 (v/v), with DCM as the extraction solvent for PAHs-containing silica gel scraped off the plate. When the spiking level is 100 ng, total recoveries of spiked matrices for four target PAHs (phenanthrene, anthracene, pyrene and chrysene) were 83.7%, 76.4%, 85.8%, and 88.7%, respectively, with relative standard deviation (RSD) between 5.0% and 6.5% (n = 4). When the spiking level is 1000 ng, associated total recoveries were 78.6%, 72.7%, 82.7% and 85.3%, respectively, with RSD between 4.4% and 5.3% (n = 4). The opti-mized method was advantageous for determination of PAHs in complex matrix due to its effective sample purification.

Optimization of Ultrasonic Extraction and Clean-up Protocol for the Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments by High-performance Liquid Chroma-tography Coupled with Fluorescence Detection

The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were purified with a miniaturized silica gel chromatographic column and analyzed with high performance liquid chromatography (HPLC) with a fluorescence detector. Ultrasonication with methanol-dichloromethane (2:1, v/v) mixture gave higher extraction efficiency than that with dichloromethane. Among the three elution solvents used in clean-up step, dichloromethane-hexane (2:3, v/v) mixture was the most satisfactory. Under the optimized conditions, the recoveries in the range of 54.82% to 94.70% with RSDs of 3.02% to 23.22% for a spiked blank, and in the range of 61.20% to 127.08% with RSDs of 7.61% to 26.93% for a spiked matrix, were obtained for the 15 PAHs studied, while the recoveries for a NIST standard reference SRM 1941b were in the range of 50.79% to 83.78% with RSDs of 5.24% to 21.38%. The detection limits were between 0.75 ng L-1 and 10.99 ng L-1for different PAHs. A sample from the Jiaozhou Bay area was examined to test the established methods.

QSAR for Photodegradation Activity of Polycyclic Aromatic Hydrocarbons in Aqueous Systems

The relationship between chemical structures and photodegradation activity of 12 PAHs is studied using DFT and HF methods, and stepwise multiple linear regression analysis method. The equilibrium geometries and vibration frequency have been investigated by considering Solvent effects using a selfconsistent reaction field based on the polarizable continuum model. With DFT and HF methods, different quantum chemical structural descriptors are obtained by quantum chemical calculation and the results with DFT method are better for QSAR model. It is concluded that the photodegradation activity is closely related to its molecular structure. In the regression analysis, the main factors affecting photodegradation rate include the energy of the highest occupied orbital EHOMO and the number of six-carbon benzene ring N1, and the QSAR model successfully established is logkb = 6.046 + 54.830EHOMO + 0.272N1. Statistical evaluation of the developed QSAR shows that the relationships are statistically significant and the model has good predictive ability. EHOMO is the most important factor influcing the photodegradation of PAHs, because the higher EHOMO is, the more easily electron will be excited and the more easily molecular will be degraded. Comparison of the photodegradation of PAHs with their biodegradation shows that the committed step of biodegradation is that the effects of microorganisms make the chemical bond break, while in the committed step of photodegradation PAHs eject electrons.

Sources and Transport of Terrigenous Organic Matters Along the East China Sea Inner Shelf: Insights from Lignin and Alkane Biomarkers

The area of East China Sea(ECS)inner shelf is an important sink of suspended particulates from Yangtze River(YR)and materials originated from YR basin.In this study,the parameters of lignin and alkane biomarkers in surface sediment samples from ECS inner shelf were determined to distinguish the sources and to trace the transport of terrigenous organic matters in the region.Our dataset showed that total alkanes with carbon numbers from 10 to 38(T-alkanes)were significantly correlated to both TAR(terrigenous/aquatic ratio)and HMW/LMW(the ratio of high molecular weight to low molecular weight alkanes)(r=0.88,P<0.05 for both),indicating that the majority of T-alkanes was predominantly originated from terrestrial sources,and T-alkanes are important constituents of terrestrial organic matters in the study area.The area was probably affected by petroleum pollution to a certain degree,as indicated by the values of carbon preference index(CPI),odd-over-even carbon number predominance(OEP)and the ratio of pristane to phytane(Pr/Ph).The values of Pr/n-C_(17) and Ph/n-C_(18) suggested a strong reductive sedimentary condition in the region with no obvious biodegradation.The content of eight lignin phenols(Σ8)decreased from the coast to the open sea,indicative of riverine input and hydrodynamic transport of terrigenous organic matters.Lignin degradation parameters presented an increasing trend from the coastline toward the open sea.The lignin vegetation parameters and alkane index(AI)suggested the predominance of non-woody angiosperms in the YR basin.The obvious correlation betweenΛ8(Σ8 normalized to 100 mg organic carbon),TAR and HMW/LMW reveals the significantly concurrent input of lignin and alkanes from terrestrial sources.

Catalytic Hydrothermal Liquefaction of Algae for Production of Bio-oil with Solid Superacid Catalyst SO_(4)^(2−)/ZrO_(2)

Solid superacid SO_(4)^(2−)/ZrO_(2)as heterogeneous catalyst was prepared to upgrade the bio-oil in the progress of hydrother-mal liquefaction(HTL)for the represented algae of Chlorella vulgaris and Enteromorpha prolifera.The solid superacid catalyst could obviously adjust the composition of the bio-oil and improve the higher heating values(HHVs).The catalytic performance could be regulated by adjusting the acid amount and acid strength of SO_(4)^(2−)/ZrO_(2).Furthermore,it was explored the catalytic effects of SO_(4)^(2−)/ZrO_(2)by the HTL for algae major model components,including polysaccharides,proteins,lipids,binary mixture and ternary mixture.The results showed that the introducing of SO_(4)^(2−)/ZrO_(2)catalyst could increase the yields of bio-oil from proteins and lipids,and avoid the Maillard reaction between polysaccharides and proteins.Moreover,a possible reaction pathway and mechanisms has proposed for the formation of bio-oils from HTL of algae catalyzed by SO_(4)^(2−)/ZrO_(2)based on the systematic research of the producing bio-oil from major model components.