Name: investigating long-distance transport of perfluoroalkyl acids in wheat via a split-root exposure technique
Uploaded: 2022-09-28T14:05:00
Description: Watch this Scientific Journal Video about Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique at JoVE.com

我们衷心感谢国家自然科学基金（NSFC 21737003）、中国高校科学基金（第2452021103号）和中国博士后科学基金（编号：2021M692651，2021M702680）的资助。

小麦种子小麦种子小麦L .被采购（见 材料表）并用于本研究。
1.小麦幼苗萌发与水培培养
<ol><li>选择大小相似的小麦种子，并用8%（w / w）过氧化氢溶液消毒15分钟。</li>
	<li>消毒后的种子用去离子水彻底冲洗，然后在室温下在黑暗中将其置于潮湿的滤纸上发芽5天。</li>
	<li>选择大约九个大小均匀的发芽幼苗，并将它们转移到装有250 mL营养液（...

<ol>
	<li>Lindstrom, A. B., Strynar, M. J., Libelo, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polyfluorinated+compounds:+Past,+present,+and+future.">Polyfluorinated compounds: Past, present, and future.</a> Environmental Science &amp; Technology. 45 (19), 7954-7961 (2011).</li><li>Kannan, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perfluoroalkyl+and+polyfluoroalkyl+substances:+Current+and+future+perspectives.">Perfluoroalkyl and polyfluoroalkyl substances: Current and future perspectives.</a> Environmental Chemistry. 8 (4), 333-338 (2011).</li><li>Cui, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Occurrence+and+tissue+distribution+of+novel+perfluoroether+carboxylic+and+sulfonic+acids+and+legacy+per/polyfluoroalkyl+substances+in+black-spotted+frog+(Pelophylax+nigromaculatus).">Occurrence and tissue distribution of novel perfluoroether carboxylic and sulfonic acids and legacy per/polyfluoroalkyl substances in black-spotted frog (Pelophylax nigromaculatus).</a> Environmental Science &amp; Technology. 52 (3), 982-990 (2018).</li><li>Negri, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exposure+to+PFOA+and+PFOS+and+fetal+growth:+a+critical+merging+of+toxicological+and+epidemiological+data.">Exposure to PFOA and PFOS and fetal growth: a critical merging of toxicological and epidemiological data.</a> Critical Reviews in Toxicology. 47 (6), 489-515 (2017).</li><li>Chi, Q., Li, Z., Huang, J., Ma, J., Wang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interactions+of+perfluorooctanoic+acid+and+perfluorooctanesulfonic+acid+with+serum+albumins+by+native+mass+spectrometry,+fluorescence+and+molecular+docking.">Interactions of perfluorooctanoic acid and perfluorooctanesulfonic acid with serum albumins by native mass spectrometry, fluorescence and molecular docking.</a> Chemosphere. 198, 442-449 (2018).</li><li>Zhang, X., Chen, L., Fei, X. C., Ma, Y. S., Gao, H. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Binding+of+PFOS+to+serum+albumin+and+DNA:+insight+into+the+molecular+toxicity+of+perfluorochemicals.">Binding of PFOS to serum albumin and DNA: insight into the molecular toxicity of perfluorochemicals.</a> Bmc Molecular Biology. 10, 16 (2009).</li><li>Pan, Y. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Worldwide+distribution+of+novel+perfluoroether+carboxylic+and+sulfonic+acids+in+surface+water.">Worldwide distribution of novel perfluoroether carboxylic and sulfonic acids in surface water.</a> Environmental Science &amp; Technology. 52 (14), 7621-7629 (2018).</li><li>Knight, E. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+investigation+into+the+long-term+binding+and+uptake+of+PFOS,+PFOA+and+PFHxS+in+soil+-+plant+systems.">An investigation into the long-term binding and uptake of PFOS, PFOA and PFHxS in soil - plant systems.</a> Journal of Hazardous Materials. 404, 124065 (2021).</li><li>Liu, Z. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crop+bioaccumulation+and+human+exposure+of+perfluoroalkyl+acids+through+multi-media+transport+from+a+mega+fluorochemical+industrial+park,+China.">Crop bioaccumulation and human exposure of perfluoroalkyl acids through multi-media transport from a mega fluorochemical industrial park, China.</a> Environment International. 106, 37-47 (2017).</li><li>Mei, W. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Per-+and+polyfluoroalkyl+substances+(PFASs)+in+the+soil-plant+system:+Sorption,+root+uptake,+and+translocation.">Per- and polyfluoroalkyl substances (PFASs) in the soil-plant system: Sorption, root uptake, and translocation.</a> Environment International. 156, 106642 (2021).</li><li>Wang, W., Rhodes, G., Ge, J., Yu, X., Li, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake+and+accumulation+of+per-+and+polyfluoroalkyl+substances+in+plants.">Uptake and accumulation of per- and polyfluoroalkyl substances in plants.</a> Chemosphere. 261, 127584 (2020).</li><li>Lu, J., Wu, J., Stoffella, P. J., Wilson, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+bisphenol+A,+nonylphenol,+and+natural+estrogens+in+vegetables+and+fruits+using+gas+chromatography-tandem+mass+spectrometry.">Analysis of bisphenol A, nonylphenol, and natural estrogens in vegetables and fruits using gas chromatography-tandem mass spectrometry.</a> Journal of Agricultural and Food Chemistry. 61 (1), 84-89 (2013).</li><li>Herschbach, C., Gessler, A., Rennenberg, H., Luttge, U., Beyschlag, W., Budel, B., Francis, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long+Distance+Transport+and+Plant+Internal+Cycling+of+N-+and+S-Compounds.">Long Distance Transport and Plant Internal Cycling of N- and S-Compounds.</a> Progress in Botany 73. , 161-188 (2012).</li><li>Liu, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake+kinetics,+accumulation,+and+long-distance+transport+of+organophosphate+esters+in+plants:+Impacts+of+chemical+and+plant+properties.">Uptake kinetics, accumulation, and long-distance transport of organophosphate esters in plants: Impacts of chemical and plant properties.</a> Environmental Science &amp; Technology. 53 (9), 4940-4947 (2019).</li><li>Wang, Z. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Xylem-+and+phloem-based+transport+of+CuO+nanoparticles+in+maize+(Zea+mays+L.).">Xylem- and phloem-based transport of CuO nanoparticles in maize (Zea mays L.).</a> Environmental Science &amp; Technology. 46 (8), 4434-4441 (2012).</li><li>Chen, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake,+accumulation,+and+translocation+mechanisms+of+steroid+estrogens+in+plants.">Uptake, accumulation, and translocation mechanisms of steroid estrogens in plants.</a> Science of the Total Environment. 753, 141979 (2021).</li><li>Felizeter, S., McLachlan, M. S., de Voogt, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake+of+perfluorinated+alkyl+acids+by+hydroponically+grown+lettuce+(Lactuca+sativa).">Uptake of perfluorinated alkyl acids by hydroponically grown lettuce (Lactuca sativa).</a> Environmental Science &amp; Technology. 46 (21), 11735-11743 (2012).</li><li>Zhou, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+into+uptake,+translocation,+and+transformation+mechanisms+of+perfluorophosphinates+and+perfluorophosphonates+in+wheat+(Triticum+aestivum+L.).">Insights into uptake, translocation, and transformation mechanisms of perfluorophosphinates and perfluorophosphonates in wheat (Triticum aestivum L.).</a> Environmental Science &amp; Technology. 54 (1), 276-285 (2020).</li></ol>

为确保该方法的准确性，必须谨慎操作，以确保管B中的加标溶液不会污染管A中的未加标溶液。本研究中给定的目标PFAAs浓度相对高于其在真实环境中的浓度，确保使用LC-MS/MS监测小麦和未加标溶液中的目标PFAAs。 
此方法存在局限性。由于每个处理组仅使用一株小麦幼苗，并且根被分成两半，如果加标溶液的初始浓度相对较低，则从最终处理中获得的生物量越少，可能导致在?...

全氟烷基酸（PFAAs）由于其优异的物理化学性质，包括表面活性以及热稳定性和化学稳定性1，2，3，广泛用于各种商业和工业产品。全氟辛烷磺酸（PFOS）和全氟辛烷酸（PFOA）是全球使用的两种最重要的PFAAs4，5，6，尽管这些化合物分别于2009年和2019年被列入国际斯德哥尔摩公约7，8。全氟辛烷磺酸和全氟辛烷磺酸由于其持久性和广泛使用，已在各种环境基质中得到广泛检测。全球不同河流和湖泊地表水中全氟辛烷磺酸和全氟辛烷磺酸的浓度分别为0.15-52.8纳克/升和0.09-29.7纳克/升9。由于使用地下水或再生水进行灌溉，也使用生物固体作为肥料，全氟辛烷磺酸和全氟辛烷磺酸广泛存在于土壤中，分别为0.01-123微克/千克和0.003-162微克/千克，10，这可能将大量全氟辛烷磺酸引入植物，对人类健康构成潜在风险。农业土壤和谷物（小麦和玉米）中的PFAA（C4-C8）浓度呈正线性相关11。因此，研究PFAAs在植物内的积累和易位势在必行。
植物中PFAAs的易位首先发生在根部到地上组织，PFAAs从根部到食用组织的易位被认为是长距离运输12，13。以前的研究已经在蔬菜和水果中检测到双酚A，壬基酚和天然雌激素14，这意味着这些化学物质可能通过韧皮部迁移。因此，揭示植物中PFAA的易位对于评估其潜在风险非常重要。然而，PFAAs的积累和易位受其在土壤中的生物利用度的影响，因此评估目标PFAAs在植物中的易位能力并不容易。此外，水培实验通常受到多种因素的限制，使得获得植物的可食用组织变得更加困难。通常，韧皮部直接从植物中收集，以观察有机化合物在植物中长距离的易位，而很难从植物幼苗中获取韧皮部15。因此，引入一种简单有效的方法，即分根技术，用于研究植物中PFAAs在相对短期暴露下的易位。至于分根研究，将一株植物幼苗的根分成两部分;一部分放入含有目标PFAA的营养液（管A），另一部分在没有PFAA的情况下放入营养液（管B）。暴露几天后，通过LC-MS / MS测量管B中的PFAA。管B中PFAA的浓度揭示了PFAAs通过植物内韧皮部的易位潜力16，17，18。
据报道，裂根实验用于研究植物中许多化合物的长距离易位，例如CuO纳米颗粒17，类固醇雌激素18和有机磷酸酯16。这些研究提供了证据，证明这些化合物可以通过韧皮部转移到植物的可食用部分。然而，PFAAs是否有助于植物的易位以及化合物特性的影响需要进一步探索。基于这些报道，本研究进行了分根实验，以揭示PFAAs在小麦中的长距离运输。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>ACQUITY UPLC BEH C18 column</td>
			<td>Waters, Milford, MA</td>
			<td></td>
			<td>Liquid chromatographic column</td>
		</tr>
		<tr>
			<td>Cleanert PEP cartridge</td>
			<td>Bonna- Angel Technologies, China</td>
			<td></td>
			<td>Solid phase extraction column</td>
		</tr>
		<tr>
			<td>Clearnert Pesticarb cartridge</td>
			<td>Bonna- Angel Technologies, China</td>
			<td></td>
			<td>Solid phase extraction column</td>
		</tr>
		<tr>
			<td>LC-MS/MS(Waters Acquity UPLC i-Class Coupled to Xevo TQ-S)</td>
			<td>Waters, Milford, MA</td>
			<td></td>
			<td>Liquid chromatography and mass spectrometry</td>
		</tr>
		<tr>
			<td>Lyophilizer&#160;</td>
			<td>Boyikang Instrument Ltd., Beijing, China</td>
			<td>FD-1A50</td>
			<td>Freeze-dried sample</td>
		</tr>
		<tr>
			<td>Masslynx</td>
			<td>Waters, Milford, MA</td>
			<td></td>
			<td>data analysis software</td>
		</tr>
		<tr>
			<td>Methyl tert-butyl ether</td>
			<td>Sigma-Aldrich Chemical Co. (St. Louis, US)</td>
			<td></td>
			<td>use for extracting target compounds from plant tissues</td>
		</tr>
		<tr>
			<td>MPFAC-MXA</td>
			<td>Wellington Laboratories (Ontario, Canada)</td>
			<td>PFACMXA0518</td>
			<td>the internal standards</td>
		</tr>
		<tr>
			<td>PFAC-MXB</td>
			<td>Wellington Laboratories (Ontario, Canada)</td>
			<td>PFACMXB0219</td>
			<td>mixture of PFAA calibration standards</td>
		</tr>
		<tr>
			<td>PFOA</td>
			<td>Sigma-Aldrich Chemical Co. (St. Louis, US)</td>
			<td>335-67-1</td>
			<td>a represent PFAAs</td>
		</tr>
		<tr>
			<td>PFOS</td>
			<td>Sigma-Aldrich Chemical Co. (St. Louis, US)</td>
			<td>2795-39-3</td>
			<td>a represent PFAAs</td>
		</tr>
		<tr>
			<td>Sodium carbonate buffer</td>
			<td>Sigma-Aldrich Chemical Co. (St. Louis, US)</td>
			<td></td>
			<td>use for extracting target compounds from plant tissues</td>
		</tr>
		<tr>
			<td>Tetrabutylammonium hydrogen sulfate</td>
			<td>Sigma-Aldrich Chemical Co. (St. Louis, US)</td>
			<td></td>
			<td>use for extracting target compounds from plant tissues</td>
		</tr>
		<tr>
			<td>Wheat seeds</td>
			<td>Chinese Academy of Agricultural Sciences (Beijing,China)&#160;</td>
			<td></td>
			<td>Triticum aestivum L.</td>
		</tr>
	</tbody>
</table>

investigating long-distance transport of perfluoroalkyl acids in wheat via a split-root exposure technique

大量的全氟烷基酸（PFAAs）被引入土壤并由植物积累，对人类健康构成潜在风险。必须研究植物内PFAA的积累和易位。长距离运输是PFAA通过韧皮部从植物叶子转移到可食用组织的重要途径。然而，以前很难在短期接触期内评估有机污染的易位潜力。裂根实验提供了一种使用水培实验有效揭示PFAAs长距离易位的解决方案，在本研究中，该实验在两个50 mL离心管（A和B）中进行，其中离心管A具有50 mL四分之一强度的Hoagland无菌营养液，而离心管B具有相同的营养浓度， 以及以给定浓度添加的目标PFAA（全氟辛烷磺酸，PFOS和全氟辛烷酸，PFOA）。将全麦根手动分成两部分，并小心地插入管A和B中。在培养箱中培养7 d并收获后，分别使用LC-MS / MS评估根，小麦芽和管A和B中的溶液中PFAA的浓度。结果表明，PFOA和PFOS经历了类似的长距离运输过程，通过韧皮部从芽到根部，并可能释放到周围环境中。因此，裂根技术可用于评估不同化学品的长距离传输。

分根实验研究了PFAAs在小麦中的长距离运输。如图 2A，C所示，全氟辛烷磺酸和全氟辛烷磺酸都可以被小麦根部吸收并转移到枝条上。在空白对照的试管A中的小麦根和溶液中未检测到PFOS和PFOA。研究发现，在未加标溶液中培养的小麦根系中检测到全氟辛烷磺酸和全氟辛烷磺酸，浓度分别为0.26纳克/克±0.02纳克/克和0.64纳克/克±0.05纳克/克干重（dw）（n=3），分别占全...

Watch this Scientific Journal Video about Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique at JoVE.com

Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique

本协议描述了一种在小麦中长距离运输全氟烷基酸的简单有效的方法。

通过裂根暴露技术 研究 全氟烷基酸在小麦中的长距离运输

Large amounts of perfluoroalkyl acids (PFAAs) have been introduced into the soil and accumulated by plants, posing potential risks to human health. It is ...

韧皮部直接从植物中收集，以观察有机化合物的远距离易位，而很难从植物幼苗中获取韧皮部。引入了一种简单有效的方法，即分根技术，以研究植物中PFAAs在相对短期暴露期间的易位。该方法还可以揭示不同化合物在植物中的长距离传输。给定的目标PFAAs浓度必须相对高于其在实际环境中的浓度，以确保在未加标溶液中监测小麦中的目标PFAA。首先选择类似大小的小麦或小麦种子，并用8%过氧化氢溶液消毒15分钟。用去离子水彻底冲洗消毒的种子。将种子放在室温下在黑暗中潮湿的滤纸上发芽5天。选择大约 9 个大小均匀的发芽幼苗，并将它们转移到装有 250 毫升 1/4 强度的 Hoagland 溶液的塑料烧杯中。在处理之前，在生长室中培养幼苗7天，在22摄氏度下循环14小时，在27摄氏度下循环10小时。对于幼苗栽培，准备 2 个离心管 A 和 B，每个离心管含有 50 毫升 1/4 强度的 Hoagland 溶液。将市售全氟辛烷酸（PFOA）和全氟辛烷磺酸（PFOS）溶解在甲醇中，并用无菌营养液作为储备溶液稀释，然后将储备溶液以每升100微克的PFOA和PFOS加入试管B中。接下来，使用镊子将小麦幼苗的整个根分成 2 等份，根连接到同一根芽，然后分别将它们插入管 A 和 B 中。用铝箔密封 2 个管，然后在培养箱中培养 7 天，在 22 摄氏度下循环 14 小时，在 27 摄氏度下循环 10 小时。7天后，收集小麦幼苗并用剪刀将它们分成3部分，例如在未加标溶液中的全氟烷基酸或PFAAs加标溶液中培养的芽和根。将植物样品在零下55摄氏度的冻干机中冷冻干燥48小时。2天后，均质化。称量根部并拍摄样品。收集加标和未加标的溶液样品。在15毫升聚丙烯管中，加入2毫升碳酸钠缓冲液，1毫升四丁基硫酸氢铵，5毫升甲基叔丁基醚，以及均质化的根或芽。完成后，以250RPM摇动管20分钟，然后在室温下以2000g离心10分钟，以获得上清液有机相。第二次提取后，将类似的处理提取物合并并在温和的氮气流中蒸发至干，然后用5毫升甲醇复溶并涡旋它们，保持相同的速度约30秒。用 5 毫升 0.1% 氢氧化铵甲醇溶液、5 毫升水和 5 毫升甲醇调节 PestiCarb 墨盒。通过PestiCarb滤芯加入5毫升提取甲醇溶液以去除色素。用5毫升甲醇洗脱小柱并收集在样品管中。将收集的10毫升甲醇溶液蒸发至干，并在涡旋前用200微升甲醇复溶，然后将样品在室温下以10， 000g离心20分钟。用 5 毫升甲醇和 5 毫升水调节极性增强聚合物提取滤芯以活化。通过小柱加入 1 毫升加标溶液或 50 毫升未加标溶液样品。用10毫升甲醇躲避目标PFAA。用温和的氮气流蒸发提取物，然后用200微升甲醇重新配制蒸发的提取物进行分析。分根实验研究了PFAAs在小麦中的长距离运输。结果表明，加标溶液中全氟辛烷磺酸和全氟辛烷磺酸分别被浓度为11.94纳克/克和30.67纳克/克干重的小麦根吸收，并以5.01纳克/克和4.17纳克干重的浓度转移到枝条上。结果发现，在未加标溶液中培养的小麦根系中检测到PFOA和PFOS，浓度分别为0.26纳克/克和0.64纳克/克干重。它表明PFOA和PFOS可以通过韧皮部从芽到根部进行长距离迁移。据指出，在未加标的营养液中也发现了全氟辛烷磺酸和全氟辛烷磺酸，浓度分别为每升17.8毫微克和每升28.5毫微克，这表明全氟辛烷磺酸和全氟辛烷磺酸可以通过卡斯帕里亚根带。必须采取预防措施，以确保试管B中的加标溶液不会污染试管A中的未加标溶液.该方法的视觉演示可以提供一个简单的操作来揭示PFAAs在小麦中的远距离运输。

Research

JoVE Journal

Environment

Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique

Optimize Flue Gas Settings to Promote Microalgae Growth in Photobioreactors via Computer Simulations

优化烟气设置通过电脑模拟来促进微藻生长的光生物反应器中

Flue gas from power plants can promote algal cultivation and reduce greenhouse gas emissions1. Microalgae not only capture solar energy more efficiently ...

科研

环境科学

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. I. Collection of Virus Samples

EPA方法1615测量肠道病毒和诺瓦克病毒发生水由文化和RT-qPCR的了。病毒样本的收集I.

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. ...

A Whole Cell Bioreporter Approach to Assess Transport and Bioavailability of Organic Contaminants in Water Unsaturated Systems

全细胞Bioreporter方法​​评估交通有机污染物的生物利用度和水饱和系统

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. II. Total Culturable Virus Assay

EPA方法1615年测量和肠道病毒水中诺如病毒发生由文化部和RT-qPCR的的。 II。总可培养病毒试验

A standardized method is required when national studies on virus occurrence in environmental and drinking waters utilize multiple analytical laboratories. ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

EPA方法1615测量肠道病毒和诺瓦克病毒发生水由文化和RT-qPCR的了。第三部分。病毒检测用RT-qPCR的

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a ...

Extraction and Analysis of Microbial Phospholipid Fatty Acids in Soils

提取及土壤微生物磷脂脂肪酸分析

Phospholipid fatty acids (PLFAs) are key components of microbial cell membranes. The analysis of PLFAs extracted from soils can provide information about ...

Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe

Implementation of Portable Emissions Measurement Systems PEMS for the Real-driving Emissions RDE Regulation in Europe

便携式排放测量系统（PEMS）在欧洲的真实驾驶排放（RDE）规例的执行情况

Vehicles are tested in controlled and relatively narrow laboratory conditions to determine their official emission values and reference fuel consumption. ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

对水生生命值评价悬浮泥沙影响的流通系统曝光

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Techniques for Investigating the Anatomy of the Ant Visual System

蚂蚁视觉系统解剖学研究方法

This article outlines a suite of techniques in light microscopy (LM) and electron microscopy (EM) which can be used to study the internal and external eye ...

Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments

多年生草试验中土壤、根际和根系微生物群落的分离与分析

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The ...

通过裂根暴露技术 研究 全氟烷基酸在小麦中的长距离运输

通过裂根暴露技术研究全氟烷基酸在小麦中的长距离运输