The Authors would first like to acknowledge all students from the freshman Biology 121- Ecology Module lab at Juniata College for their help in generating data used in this study. We would also like to thank Dr. Randy Bennett, Chris Walls, Sherry Isenberg, and Taylor Cox for their assistance in acquiring materials necessary to develop this methodology. Additionally, we would like to thank Dr. Norris Muth and Dr. John Unger for their advice on methodological development and Dr. Jill Keeney and the Biology department for their support of this endeavor. We would also like to thank the anonymous reviewers that have helped to shape and focus this manuscript.&#160; Last but not least, I&#39;d like to thank Hudson Grant for his help with the initial stonefly collection for use in development of this technique

注意:这个实验没有使用脊椎动物，因此没有需要由杰尼阿塔学院研究所的动物护理和使用委员会的批准。然而，对于个人适应与脊椎动物使用这种方法，IACUC批准，应寻求。 领域样品采集<ol><li>确定并收集，存储能力评估潜在的野外场地，运输石蝇迅速在1小时过境最大推荐时间减少在途时间。 </li><li>在选定的领域站点执行球网采样下列标准球网的程序足够的时间来收集至少35石蝇12。 </li><li>收集50升流的水和岩石的与流2厘米的最大直径。 </li><li>放置水族馆中设定为数据流部位的温度的冰箱。在分发流现场收集到的岩石和水族馆，每水族馆4升溪水填补。将20每水族馆-30收集石蝇和放置连接到水族馆鼓泡到每个罐中鼓泡石和打开鼓泡向室内空气连续地添加到水中。 </li><li>允许石蝇调整到在水族馆的48小时期间新的环境。 </li></ol><img alt="图1" src="/files/ftp_upload/54430/54430fig1.jpg" /> 图1.为溶解氧操作。（A）1）安装铜管男性软管倒钩2）塞密封的位置，以检查确保密封性好烧瓶中。 （B）1）2 L侧臂烧瓶装满1.9升水2）气体管和分别空气鼓泡器（蓝色），于氮气鼓泡和房间空气鼓泡使用，3）氮罐和衡量值4）2升烧瓶洋溢着0.4升的水与真空管淹没5）溶解氧测定仪。 <a href="https://www.jove.com/files/ftp_upload/54430/54430fig1large.jpg" target="_blank">请点击这里</a>查看该图的放大版本。 2.实验设置<ol><li>上的台顶，一个标准的薄壁真空管连接到2L侧臂烧瓶的侧臂如图所示（ 图1B 1）。 </li><li>与3升的塑料容器保持收集流水在冰箱设置为12℃的1.9升流的水的填充烧瓶中。 </li><li>放在一个托盘大到足以容纳周围的侧臂瓶冰浴不遮挡烧瓶内部的看法和填充用冰托盘中的烧瓶和油管。 </li><li>钻两个直径3mm的孔的橡胶塞，以允许1）的铜管的通道，以输送气体到容器和2）的DO计， 如图1B中的探头插入2升侧臂烧瓶（1） 。 </li><li>使从塞子的边缘的横向切口的孔中的一个，以使DO探头的导线的座位到塞子。 </li><li>连接耦合器带有3毫米公软管倒钩（ 图1A 1）一块直径为2毫米铜管。确保该管足够长以10厘米烧瓶底部的内达到通过塞子到达时间。 </li><li>放置管具有耦合器虽然在止动件的第二孔，直到从止动件的底部的长度是足够到10cm烧瓶底部的内达到。 </li><li>连接0.75米长，薄壁聚乙烯燃气管的直径为3mm到管道上的耦合器。 </li><li>两者DO探头和铜管滑入烧瓶中并密封与止动烧瓶。 </li><li>检查塞子和烧瓶，以及管和塞子中的探针导线之间的紧密配合之间的安全密封。 </li><li>补的1L烧瓶加入0.4升的自来水，并放置相邻的冰浴，并在真空烧瓶中的托盘。 </li><li>淹没聚乙烯管从大保温瓶来进1升烧瓶中的水。固定用胶带管，使得其将通过实验保持浸没。 </li><li>从保温瓶3毫米直径的天然气管线连接到一个水族馆室内空气鼓泡。在水族馆起泡器，它引入了室内空气和氧气送到堵水开始泡在2升烧瓶上的水。 </li><li>监控溶解氧浓度及水分的温度与DO仪5分钟，或直至溶解氧的平衡在腔室内建立，使得在溶解氧很少改变正在发生。 </li></ol> 3.测试实验装置的稳定性<ol><li>测试每个设置为之前除了石蝇的DO稳定性。 </li><li>添加三个或四个石头到2升瓶，使石蝇有基材利于俯卧撑。 </li><li>通过从鼓泡断开气体管，并将其附加到氮气行开始的DO的试用操作。 </li><li>开始在立方英尺每小时（CFH）20约40氮气鼓泡秒至1分钟。 </li><li>一旦溶解氧已0.5毫克/升的目标浓度的内下降到时，流程降低到15 CFH和允许的浓度降低到目标。 </li><li>立即停止氮气流下一旦达到目标浓度。 </li><li>使用水族馆室内空气鼓泡至浓度返回到目标浓度如果溶解氧减小低于目标。 </li><li>如果做一套行动的测试过程中是不稳定的再检查水量仍处于1.9 L和没有水已经起泡了，水温稳定，不改变，并在所有接头密封显得紧，密封。 </li><li>一旦三个试验已经完成，并实验者在控制DO的能力有信心，附加气体线起泡和气泡再平衡。 </li><li>泡到平衡通过附加3mm直径的气体管线的水族馆起泡和开始加入室内空气的到水中，直到浓度氧气在水中不增​​加或更改3分钟。 </li><li>一旦处于平衡状态，停止冒泡和启封烧瓶。 </li></ol> 4. StoneFly的俯卧撑实验<ol><li>由观察员人数除以石蝇的总数确定试验来执行的数目。 </li><li>确定2和10毫克/升之间不同DO水平来评价石蝇的行为反应（俯卧撑的数量）。 </li><li>设置每试验一锥形瓶并添加石蝇的数目相等，因为有观察员至烧瓶（该设计内4石蝇），探针和管放回烧瓶，然后重新密封的橡胶塞的烧瓶中。 注:初始DO为10mg / L浓度被选为第一个观察点，因为它是流从其中石蝇进行取样的溶解氧浓度。 </li><li>一旦水是在10毫克/升通过鼓泡以下步骤2.10-2.11，记录开始水温，并允许石蝇附加到烧瓶中的岩石基体。 </li><li>仅指派一名观察员观看一个StoneFly的保证俯卧撑的行为，这是由StoneFly的表现上下肢体动作计数准确。 </li><li>算并记录在3分钟的观察期的过程中观察到的俯卧撑的数目。 </li><li>操纵DO到下一个试验的DO水平，并重复3分钟的观察期，附加的实验水平。 注意:在这个实验设计，三个不同的DO水平进行了评价。 </li></ol> 5.统计分析<ol><li>向在一组为给定的DO试验执行在四个石蝇俯卧撑的统计分析使用平均数。 </li><li>使用免费的R统计计算软件12在俯卧撑和使用每个实验试的顺序DO浓度的数量进行方差分析的分析（DO级）和温度COVariates。分析DO作为单个因素的离散电平。 </li><li>使用残差的安德森-达林正态性检验，检查正常13。 </li><li>通过绘制针对DO浓度俯卧撑的平均数对数据执行线性回归。 </li></ol>

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The authors declare that they have no competing financial interests.

关键步骤 这个程序提供了一个简单而有效的方式来操作DO在实验室环境对水生生物进行行为研究。我们发现有以几个关键步骤/项意识到执行该实验是直接相关的结果时的感觉。在一个试验中，它是保持室压力，以避免在水上方的气体的分压的变化的关键，和随后的DO波动。按照协议的"试实验装置的稳定"小节中所列的步骤是关键的。检查与烧瓶塞子的密封，保证真空管的完全浸没到水的1升烧?...

溶解氧（DO）是在调解一些水生生态系统中的生物和生态过程的重要关键生理参数。暴露于急性和慢性亚致死缺氧减少某些水生昆虫的生长率，降低暴露1昆虫的生存。该协议的开发提供一个可控的方法来操纵溪水DO水平，观察动物行为的影响。由于所有的有氧水生生物的生存，为了生存和繁殖依赖于氧浓度，溶解氧浓度的变化往往反映在生物行为变化。更多的移动水生无脊椎动物和鱼类已观察到寻求语言环境具有较高的DO 2,3低氧浓度（缺氧）响应。对于流动性较差的水生生物，行为适应增加DO的摄入量可能是唯一可行的选择。 PLEC的水生底栖动物秩序的OPTera（StoneFly的）已被指出以执行"上推"运动，以增加水中的氧的流量，和吸收，在其外部鳃4 - 6。这些适应性行为已在自然的环境，并在实验室实验中观察到。 在水中溶解氧的实验室操作开辟了动物行为研究显著的机会，但在方法上部署显著存在差距。例如，一项研究使用的大型水族馆评估以下用氮气脱气大嘴低音的生理响应时间（ 加州鲈 ）缺氧的环境中，但很少详细给出的方法7。使用氮气和多孔石将气体输送到水，减少水分8 DO描述上斑马鱼（ 斑马鱼 ）进行的另一项研究。对于基于化学的应用程序，对于溶剂的脱气方法使用专门的设备9 - 11从溶剂除去氧气，但不会是适合动物行为的研究。虽然这些研究采用的方法来从水中除去氧气，没有描述的方法可以查明将允许对动物行为评价响应于DO变化。 下面描述这种方法是试图通过使用氮气充分描述了的水的DO操作的协议。此外，这种方法对观察StoneFly的行为（如俯卧撑）之间的关系发展，去做一些在大一级别的生物实验室使用。其中一个这种方法的主要好处是，它可以很容易地与常用玻璃器皿和大多数中等和高等教育机构可获得的材料在实验室内进行。该协议也很容易适应，允许个人扩展，以满足提出的研究或教学应用目标的过程。 </p&gt;

<table border="0" cellpadding="0" cellspacing="0" width="665">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Filter flask 2 L</td>
			<td style="width:163px;">Pyrex</td>
			<td style="width:119px;">5340</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Rubber Stopper size 6</td>
			<td style="width:163px;">Sigma-Aldrich</td>
			<td style="width:119px;">Z164534</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Nalgene 180 Clear Plastic Tubing</td>
			<td style="width:163px;">Thermo Scienfitic</td>
			<td>8001-1216</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Whisper 60 air pump</td>
			<td style="width:163px;">Tetra</td>
			<td style="width:119px;">N/A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Standard flexible Air line tubing</td>
			<td style="width:163px;">Penn Plax</td>
			<td>ST25</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">0.25 inch Copper tubing</td>
			<td style="width:163px;">Lowes Home Improvement</td>
			<td align="right">23050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Male hose barb</td>
			<td style="width:163px;">Grainger</td>
			<td style="width:119px;">5LWH1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Female Connector</td>
			<td style="width:163px;">Grainger</td>
			<td style="width:119px;">20YZ22</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Heavy Duty Dissolved Oxygen Meter</td>
			<td style="width:163px;">Extech</td>
			<td style="width:119px;">407510</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Nitrogen gas</td>
			<td style="width:163px;">Matheson TRIGAS</td>
			<td style="width:119px;">N/A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Radnor AF150-580 Regulator</td>
			<td style="width:163px;">Airgas</td>
			<td style="width:119px;">RAD64003036</td>
			<td></td>
		</tr>
	</tbody>
</table>

a simple approach to manipulate dissolved oxygen for animal behavior observations

操纵溶解氧（DO）在实验室环境的能力有显著应用调查若干生态和生物体的行为的问题。这里所描述的协议提供了一种简单的，可重复，并且控制方法来操纵DO来研究从低氧和缺氧条件下得到的水生生物的行为反应。在执行的水脱气用氮气在实验室设置常用生态（水生）应用没有明确的方法存在于文献中，并且该协议是第一个描述的协议以degasify水来观察生物体反应。这种技术和协议是为水生无脊椎动物直接应用开发;然而，小鱼类，两栖类，和其它水生脊椎动物可以很容易被取代。它允许从2毫克/升，以11毫克/升与稳定性DO水平的容易操纵长达5分钟的动物观察期。超过5分钟的观察期水温开始上升，并在10分钟DO水平变得太不稳定维护。该协议可扩展到研究有机体，重现性好，可靠，允许快速实施到入门教学实验室和高层次的研究应用。这种技术的预期的结果应与溶解氧改变生物体的行为反应。

<html>所描述的设置六个试验是由24新生本科生教学实验室环境进行量化石蝇响应不同的溶解氧浓度的水进行俯卧撑的数量。俯卧撑的DO水平内，每个试验中进行的平均数为汇集暗算溶解氧水平俯卧撑如图2所示 。方差分析进行最初利用溶解氧浓度，试验的顺序，温度，以及所有的变量之间的相互作用。结果显示，只有做浓度显著影响由石蝇进行俯卧撑的数量（R ...

Watch this Scientific Journal Video about A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations at JoVE.com

A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

本文介绍了一个简单的和可重复的协议来操作溶氧条件在实验室环境对动物行为的研究。该协议可能在教学和研究实验室的设置可用于评估在溶解氧浓度的变化无脊椎动物，鱼类，两栖类或生物体的反应。

一个简单的方法来操作的动物行为观察溶解氧

The ability to manipulate dissolved oxygen (DO) in a laboratory setting has significant application to investigate a number of ecological and organismal ...

a-simple-approach-to-manipulate-dissolved-oxygen-for-animal-behavior

Research

JoVE Journal

Environment

9.2K 次观看.  Juniata College. 本文介绍了一个简单的和可重复的协议来操作溶氧条件在实验室环境对动物行为的研究。该协议可能在教学和研究实验室的设置可用于评估在溶解氧浓度的变化无脊椎动物，鱼类，两栖类或生物体的反应。 

视频: A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

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

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is not an appropriate measure for its availability; bioavailability rather depends on the dynamic interplay of potential mass transfer (flux) of a compound to a microbial cell and the capacity of the latter to degrade the compound. In water-unsaturated parts of the soil, mycelia have been shown to overcome bioavailability limitations by actively transporting and mobilizing organic compounds over the range of centimeters. Whereas the extent of mycelia-based transport can be quantified easily by chemical means, verification of the contaminant-bioavailability to bacterial cells requires a biological method. Addressing this constraint, we chose the PAH fluorene (FLU) as a model compound and developed a water unsaturated model microcosm linking a spatially separated FLU point source and the FLU degrading bioreporter bacterium Burkholderia sartisoli RP037-mChe by a mycelial network of Pythium ultimum. Since the bioreporter expresses eGFP in response of the PAH flux to the cell, bacterial FLU exposure and degradation could be monitored directly in the microcosms via confocal laser scanning microscopy (CLSM). CLSM and image analyses revealed a significant increase of the eGFP expression in the presence of P. ultimum compared to controls without mycelia or FLU thus indicating FLU bioavailability to bacteria after mycelia-mediated transport. CLSM results were supported by chemical analyses in identical microcosms. The developed microcosm proved suitable to investigate contaminant bioavailability and to concomitantly visualize the involved bacteria-mycelial interactions.

A whole cell bioreporter assay with Burkholderia sartisoli RP037-mChe was developed to detect fractions of an organic contaminant (i.e., fluorene) available for bacterial degradation after active transport by mycelia bridging air-filled pores in a water unsaturated model system.

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 ...

科研

环境科学

A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and enables to perform rapid, automated and simple SPE. The pre-concentrated solution is compatible with analysis by immunoassay, with a low organic solvent content. A method is described for the extraction and pre-concentration of natural hormone 17&#946;-estradiol in 100 ml water samples. Reverse phase SPE is performed with octadecyl-silica sorbent and elution is done with 200 &#181;l of methanol 50% v/v. Eluent is diluted by adding di-water to lower the amount of methanol. After preparing manually the SPE column, the overall procedure is performed automatically within 1 hr. At the end of the process, estradiol concentration is measured by using a commercial enzyme-linked immune-sorbent assay (ELISA). 100-fold pre-concentration is achieved and the methanol content in only 10% v/v. Full recoveries of the molecule are achieved with 1 ng/L spiked de-ionized and synthetic sea water samples.

A protocol for the extraction and pre-concentration of estradiol from water samples by using an automated and miniaturized system is presented.

对水样的自动固相萃取小污染物的免疫学分析的简单方法

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and ...

How to Create Conditioned Taste Aversion for Grazing Ground Covers in Woody Crops with Small Ruminants

Conditioned taste aversion (CTA) is a learning behavior process where animals are trained to reject certain feed after gastrointestinal discomfort has been produced. Lithium chloride (LiCl) is the preferred agent used in livestock to induce CTA because it specifically stimulates the vomit center. In addition, LiCl is commercially available, and easy to prepare and administer using a drenching gun. Nevertheless, some factors have to be considered to obtain an effective long-lasting CTA, which allows small ruminants to graze during the cropping season. A key aspect is to use animals with no previous contact with the target plant (the plant chosen to be avoided; new feed). Due to their native neophobic feeding behavior, small ruminants can easily associate the negative feedback effects with the new feed, resulting in a strong and persistent CTA. The recommended doses are 200 and 225 mg LiCl/kg body weight (BW) for goats and sheep, respectively. To induce CTA, 100 g of the target plant should be individually offered for at least 30 min, and LiCl administered thereafter if the intake is greater than 10 g. Each time the animal eats the target plant without negative consequences, the CTA becomes weaker. Consequently, to minimize the risk of target plant consumption, it is essential to have sufficient palatable ground cover available. The presence of an alternative feed (of quality and quantity) prevents the accidental consumption of the target plant. A close monitoring of the flock is recommended to remove and re-dose any animal consuming more than 4 bites or 10 g of the target plant. At the beginning of each grazing season, check the CTA status of each animal before moving them to the crop.

Feeding behavior preferences in livestock can be modified to implement a grazing management plan in woody crops. Here, we present a protocol to show a lithium chloride dose after eating a new plant that induces conditioned taste aversion.

如何创建条件性味觉厌恶放牧在地面木本作物与小反刍动物封面

Conditioned taste aversion (CTA) is a learning behavior process where animals are trained to reject certain feed after gastrointestinal discomfort has ...

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in nutrient and gas cycles. After cores with intact sediment-water interfaces are collected, they are submerged in incubation tanks and kept under aerobic conditions at in situ temperatures. To initiate a time course of overlying water chemistry, cores are sealed without bubbles using a top cap with a suspended stirrer. Time courses of 4-7 sample points are used to determine the rate of sediment water exchange. Artificial illumination simulates day-time conditions for shallow photosynthetic sediments, and in conjunction with dark incubations can provide net exchanges on a daily basis. The net measurement of N2 is made possible by sampling a time course of dissolved gas concentrations, with high precision mass spectrometric analysis of N2:Ar ratios providing a means to measure N2 concentrations. We have successfully applied this approach to lakes, reservoirs, estuaries, wetlands and storm water ponds, and with care, this approach provides valuable information on biogeochemical balances in aquatic ecosystems.

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

Here, we present small core incubations for the measurement of sediment-water gas and solute exchange. These will provide reliable measurements of sediment-water exchange that assess the role of sediment in influencing biological and biogeochemical processes in aquatic ecosystems.

Ø的底栖交易所<sub&gt; 2</sub&gt;，N<sub&gt; 2</sub&gt;和营养盐使用小的核心孵化

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in ...

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

VacuSIP，对改进的方法INEX<em&gt;原位</em&gt;颗粒物与测量溶解的化合物加工后主动悬挂给料机

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Understanding Dissolved Organic Matter Biogeochemistry Through In Situ Nutrient Manipulations in Stream Ecosystems

Dissolved organic matter (DOM) is a highly diverse mixture of molecules providing one of the largest sources of energy and nutrients to stream ecosystems. Yet the in situ study of DOM is difficult as the molecular complexity of the DOM pool cannot be easily reproduced for experimental purposes. Nutrient additions to streams however, have been shown to repeatedly alter the in situ and ambient DOM pool. Here we demonstrate an easily replicable field-based method for manipulating the ambient pool of DOM at the ecosystem scale. During nutrient pulse experiments changes in the concentration of both dissolved organic carbon and dissolved organic nitrogen can be examined across a wide-range of nutrient concentrations. This method allows researchers to examine the controls on the DOM pool and make inferences regarding the role and function that certain fractions of the DOM pool play within ecosystems. We advocate the use of this method as a technique to help develop a deeper understanding of DOM biogeochemistry and how it interacts with nutrients. With further development this method may help elucidate the dynamics of DOM in other ecosystems.

Understanding Dissolved Organic Matter Biogeochemistry Through In Situ Nutrient Manipulations in Stream Ecosystems

Dissolved organic matter provides an important source of energy and nutrients to stream ecosystems. Here we demonstrate a field-based method to manipulate the ambient pool of dissolved organic matter in situ through easily replicable nutrient pulses.

了解溶解有机物生物地球化学通过<em&gt;原位</em&gt;在河流生态系统营养手法

Dissolved organic matter (DOM) is a highly diverse mixture of molecules providing one of the largest sources of energy and nutrients to stream ecosystems. ...

Basic Research in Plasma Medicine - A Throughput Approach from Liquids to Cells

In plasma medicine, ionized gases with temperatures close to that of vertebrate systems are applied to cells and tissues. Cold plasmas generate reactive species known to redox regulate biological processes in health and disease. Pre-clinical and clinical evidence points to beneficial effects of plasma treatment in the healing of chronic ulcer of the skin. Other emerging topics, such as plasma cancer treatment, are receiving increasing attention. Plasma medical research requires interdisciplinary expertise in physics, chemistry, and biomedicine. One goal of plasma research is to characterize plasma-treated cells in a variety of specific applications. This includes, for example, cell count and viability, cellular oxidation, mitochondrial activity, cytotoxicity and mode of cell death, cell cycle analysis, cell surface marker expression, and cytokine release. This study describes the essential equipment and workflows required for such research in plasma biomedicine. It describes the proper operation of an atmospheric pressure argon plasma jet, specifically monitoring its basic emission spectra and feed gas settings to modulate reactive species output. Using a high-precision xyz-table and computer software, the jet is hovered in millisecond-precision over the cavities of 96-well plates in micrometer-precision for maximal reproducibility. Downstream assays for liquid analysis of redox-active molecules are shown, and target cells are plasma-treated. Specifically, melanoma cells are analyzed in an efficient sequence of different consecutive assays but using the same cells: measurement of metabolic activity, total cell area, and surface marker expression of calreticulin, a molecule important for the immunogenic cell death of cancer cells. These assays retrieve content-rich biological information about plasma effects from a single plate. Altogether, this study describes the essential steps and protocols for plasma medical research.

A high-throughput cold physical plasma treatment protocol of liquids and cells is shown. It involves setting up different feed gas compositions for plasma ignition, measuring the plasma&#39;s emission spectra, and the subsequent analysis of liquids and cellular activity after plasma treatment.

等离子体医学基础研究--从液体到细胞的吞吐量方法

In plasma medicine, ionized gases with temperatures close to that of vertebrate systems are applied to cells and tissues. Cold plasmas generate reactive ...

A Simple Planting Technique for Re-establishing Trees Where Frequent Inundation Occurs

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with herbaceous plants. This protocol describes a simple, cost-effective tree planting technique needed for restoring degraded Everglade tree islands. The design is patterned after a natural Everglades process that creates floating peat islands, which allows tree survival and growth in flooded conditions and often leads to the development of tree islands. Commercially available peat bags were used as the medium for the growth and establishment of potted native tree saplings. The pop-up configuration floated initially and provided additional elevation to minimize inundation, with a single native tree species sapling and a single tree fertilizer spike. During a 3 year study involving 105 pop-ups, most plants survived (80%) and many thrived. Determining whether this technique can establish trees on a degraded tree island will require longer studies and extensive field tests.

This protocol describes a simple, cost-effective tree planting technique for restoring degraded Everglades tree islands that experience inundation. The design creates an island (pop-up) which floats initially and adds elevation to promote tree survival and growth under flooded conditions.

常淹发生的重构树简易造林技术

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with ...

Lab-Scale Model to Evaluate Odor and Gas Concentrations Emitted by Deep Bedded Pack Manure

A lab-scaled simulated bedded pack model was developed to study air quality and nutrient composition of deep-bedded packs used in cattle mono-slope facilities. This protocol has been used to effectively evaluate many different bedding materials, environmental variables (temperature, humidity), and potential mitigation treatments that can improve air quality in commercial deep-bedded mono-slope facilities. The model is dynamic and allows researchers to easily collect many chemical and physical measurements from the bedded pack. Weekly measurements, collected over the course of six to seven weeks, allows sufficient time to see changes in air quality measurements over time as the bedded pack matures. The data collected from the simulated bedded packs is within the range of concentrations previously measured in commercial deep-bedded mono-slope facilities. Past studies have demonstrated that 8 - 10 experimental units per treatment are sufficient to detect statistical differences among the simulated bedded packs. The bedded packs are easy to maintain, requiring less than 10 minutes of labor per bedded packs per week to add urine, feces, and bedding. Sample collection using the gas sampling system requires 20 - 30 minutes per bedded pack, depending on the measurements that are being collected. The use of lab-scaled bedded packs allows the researcher to control variables such as temperature, humidity, and bedding source that are difficult or impossible to control in a research or commercial facility. While not a perfect simulation of &#34;real-world&#34; conditions, the simulated bedded packs serve as a good model for researchers to use to examine treatment differences among bedded packs. Several lab-scale studies can be conducted to eliminate possible treatments before trying them in a research or commercial-sized facility.

A protocol has been developed to measure gases, odors, and nutrient composition in lab-scaled bedded manure packs, which can be used to study ways to improve air quality in commercial cattle facilities using deep-bedded manure packs.

用实验室尺度模型评价深层包粪排放的恶臭和气体浓度

A lab-scaled simulated bedded pack model was developed to study air quality and nutrient composition of deep-bedded packs used in cattle mono-slope ...

Detached Leaf Assays to Simplify Gene Expression Studies in Potato During Infestation by Chewing Insect Manduca sexta

The multitrophic nature of gene expression studies of insect herbivory demands large numbers of biological replicates, creating the need for simpler, more streamlined herbivory protocols. Perturbations of chewing insects are usually studied in whole plant systems. While this whole organism strategy is popular, it is not necessary if similar observations can be replicated in a single detached leaf. The assumption is that basic elements required for signal transduction are present within the leaf itself. In the case of early events in signal transduction, cells need only to receive the signal from the perturbation and transmit that signal to neighboring cells which are assayed for gene expression.
The proposed method simply changes the timing of the detachment. In whole plant experiments, larvae are confined to a single leaf which is eventually detached from the plant and assayed for gene expression. If the order of excision is reversed, from last in whole plant studies, to first in the detached study, the feeding experiment is simplified.
Solanum tuberosum var. Kennebec is propagated by nodal transfer in a simple tissue culture medium and transferred to soil for further growth if desired. Leaves are excised from the parent plant and relocated to Petri dishes where the feeding assay is conducted with the larval stages of M. sexta. Damaged leaf tissue is assayed for the expression of relatively early events in signal transduction. Gene expression analysis identified infestation-specific Cys2-His2 (C2H2) transcription factors, confirming the success of using detached leaves in early response studies. The method is easier to perform than whole plant infestations and uses less space.

The presented method creates natural herbivore damaged plant tissue through the application of Manduca sexta larvae to detached leaves of potato. The plant tissue is assayed for expression of six transcription factor homologs involved in early responses to insect herbivory.

分离叶测定,以简化马铃薯中基因表达研究,在咀嚼昆虫曼杜卡性塔感染

The multitrophic nature of gene expression studies of insect herbivory demands large numbers of biological replicates, creating the need for simpler, more ...