This work was supported by Natural Sciences and Engineering Research Council of Canada (grant 402105), Canadian Foundation for Innovation (grant 129087) and Alberta Education and Training (grant AAETRCP-12-026-SEG) to RJC.

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The authors have nothing to disclose.

소형 형식으로 조류 성장. 현재 실험에서 복제가 증가 될 수 있도록 마이크로 타이 터 플레이트에서 1ml의 배양 부피 조류 배양의 소형화를 허용한다. 이 녹조류는 실험 내내 건강 보장하는 것이 중요하다; 조류의 영양 요건이 충족 될 수 있도록, 다양한 조류 매체를 평가하기 위해 마이크로 타이 터 플레이트 포맷을 사용하여, 성장 곡선 (도 2)를 수행한다. 또한,이?...

식물 플랑크톤의 생리는 전통적으로 원뿔 플라스크에 20 ㎖에서 carboys 1-7에서 5 L에 이르는 메조 규모의 실험에서 연구되어왔다. 각 시점에 대한 복제 샘플을 희생하는 것이 관리하기 어려운 실험 장치를 만들어으로이 실험 규모는 실험 모니터링을위한 서브 샘플링을 필요로한다. 줄이거 나 대량의 서브 샘플링 및 의사 - 복제의 제한을 제거한다 조류 생리학 실험 실험 용적을 소형화하여 일주 동일한 인큐베이터 공간을 사용하면서 기능은 독립적 인 실험의 수를 증가시키는. 마이크로 타이 터 플레이트 포맷은 가변 실험적 조건에서 조류를 조작 1ml의 배양 부피를 사용하여 조류 생물 검정을 위해 개발되었다. 실험이 작은 부피 복제물의 수가 증가 될 수 있도록 허용 복제에 의한 샘플 간의 감소 가변성 실험의 재현성을 증가(그림 2) 12 1백40일에 대한 실험 컨트롤 (즉, 무균 조류 배양)를 유지하면서 실험하고, 진정한 복제를 할 수 있습니다. 이 마이크로 타이 터 플레이트 형식은 쉽게 같은 실험 다양한 질문에 대한 적응 : 박테리아가 조류 호스트와 공생 중성 또는 병원성 상호 작용을해야합니까? 조류의 복합 자극의 추가 또는 독성인가? 이들 및 다른 문제는이 새로운 포맷을 사용하여 9-11 빠른 높은 처리량 방법으로 해결할 수있다. 48 웰 마이크로 타이 배양 플레이트는 각 1 ㎖를 잘 단일 시간 시점에서 샘플링 독립적 인 실험 장치가 될 수 있습니다. 다양한 매개 변수를 포함하여 1 ml의 볼륨에서 샘플링, 이에 국한되지 수 있습니다 WATER-펄스 진폭 변조 (WATER-PAM) 형광 측정 (재료 및 장비 표 참조) 1을 사용 엽록소 형광 및 광 화학적 매개 변수3. WATER-PAM의 형광 측정 조류 13의 실험을 모니터링하는 데 사용할 수있는 신속하고 비 침습적 방법이다. 14, 15 (WATER-PAM 4 ml의 볼륨 - - 2 중간에 희석 문화의 300 μL 150) 그것은 작은 문화 볼륨에서 광합성 효율과 광계 건강을 측정 할 수 있습니다. WATER-PAM의 형광 측정에 더하여,이 설정을 포함한 다른 다양한 파라미터를 측정하는데 사용될 수 있으나, 이에 제한되지 : 조류 세포 및 조류 세포 형태의 변화에​​ 부착 된 박테리아를 시각화하는 현미경; 단위 (CFU) 수를 형성하는 박테리아 식민지; 및 조류 세포 수 및 식별 주민들을위한 유동 세포 계측법.

<table border="0" cellpadding="0" cellspacing="0" width="1233">
	<tbody>
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			<td height="21" style="height:21px;width:413px;">Name of Material/ Equipment</td>
			<td style="width:328px;">Company</td>
			<td style="width:331px;">Catalog Number</td>
			<td style="width:163px;">Comments/Description</td>
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			<td height="20" style="height:20px;">10 cu. ft. Diurnal Incubator (6012-1)</td>
			<td>Caron Corporate</td>
			<td>112310-6012-1-11</td>
			<td><a href="http://www.caronproducts.com">www.caronproducts.com</a></td>
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			<td height="23" style="height:23px;">Nunc EasYFlask 25cm2, Vent/Close Cap, 7mL working volume, 200/Cs&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td>N156340</td>
			<td><a href="http://www.fishersci.ca">www.fishersci.ca</a></td>
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			<td height="20" style="height:20px;">Multiwell TC Plates &#8211; 48 Well</td>
			<td>BD Biosciences Discovery Labware</td>
			<td>353078</td>
			<td><a href="http://www.bdbiosciences.com/">www.bdbiosciences.com</a></td>
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			<td height="20" style="height:20px;">P1000 Gilson The Pipetting Standard&#8212;Gilson&#39;s Pipetman</td>
			<td>Mandel Scientific Company Inc.</td>
			<td>GF-F123602</td>
			<td><a href="http://www.mandel.ca">www.mandel.ca</a></td>
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		<tr height="20">
			<td height="20" style="height:20px;">P10mL Gilson The Pipetting Standard&#8212;Gilson&#39;s Pipetman</td>
			<td>Mandel Scientific Company Inc.</td>
			<td>GF-F161201</td>
			<td><a href="http://www.mandel.ca">www.mandel.ca</a></td>
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			<td height="20" style="height:20px;">Wide Orifice Tips nonsterile [100&#8211;1250 &#181;L]</td>
			<td>VWR International</td>
			<td>89079-468</td>
			<td><a href="http://www.ca.vwr.com">www.ca.vwr.com</a></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ultrafine Tips nonsterile [100&#8211;1250 &#181;L]</td>
			<td>VWR International</td>
			<td>89079-470</td>
			<td><a href="http://www.ca.vwr.com">www.ca.vwr.com</a></td>
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			<td height="20" style="height:20px;">Finntip 10mL [Vol: 1-10mL]</td>
			<td>Thermo Fisher Scientific</td>
			<td>9402151</td>
			<td><a href="http://www.fishersci.ca">www.fishersci.ca</a></td>
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			<td height="20" style="height:20px;">WATER-Pulse Amplitude Modulation (Water-ED)</td>
			<td>Heinz Walz GmbH, Effeltrich, Germany</td>
			<td>EDEE0232</td>
			<td><a href="http://www.walz.com">www.walz.com</a></td>
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			<td height="20" style="height:20px;">15 mm diameter quartz glass cuvette (WATER-K)</td>
			<td>Caron Corporate</td>
			<td></td>
			<td><a href="http://www.caronproducts.com">www.caronproducts.com</a></td>
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			<td height="20" style="height:20px;">Sodium&#160;Chloride&#160;(Crystalline/Certified ACS), Fisher Chemical</td>
			<td>Thermo Fisher Scientific</td>
			<td>Thermo Fisher Scientific</td>
			<td><a href="http://www.fishersci.ca">www.fishersci.ca</a></td>
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			<td height="20" style="height:20px;">BD Difco Marine Broth 2216</td>
			<td>BD Biosciences Discovery Labware</td>
			<td>BD Biosciences Discovery Labware</td>
			<td><a href="http://www.bdbiosciences.com">www.bdbiosciences.com</a></td>
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			<td height="20" style="height:20px;">BD Bacto Agar</td>
			<td>BD Biosciences Discovery Labware</td>
			<td>BD Biosciences Discovery Labware</td>
			<td><a href="http://www.bdbiosciences.com">www.bdbiosciences.com</a></td>
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			<td height="21" style="height:21px;">L1 Medium Kit, 50L</td>
			<td>NCMA [National Center for Marine Algae and Microbiota</td>
			<td>NCMA [National Center for Marine Algae and Microbiota</td>
			<td><a href="http://www.ncma.bigelow.org">www.ncma.bigelow.org</a></td>
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</table>

a small volume bioassay to assess bacterial/phytoplankton co-culture using water-pulse-amplitude-modulated (water-pam) fluorometry

배양 실험 1-7에 걸쳐 서브 샘플링 될 수 있도록 미세 조류의 실험 조작을위한 종래의 방법은 대량 배양 (5 L 내지 20 ml)에 사용했다. 대량의 서브 샘플링 다양한 이유로 문제가 될 수있다 : 1)는 총 부피와 표면적의 변화 원인은 다음 실험 기간 동안 배양 체적비; 2) 의사 복제 (즉, 동일한 치료 플라스크 8에서 샘플)는 종종 오히려 진정한 복제물 (복제 치료에서 즉, 샘플링)보다 채용을 복제; 3) 실험 기간은 총 부피에 의해 제한된다; 4) 배양 무균 또는 일반적인 세​​균 미생물 오염은 일반적으로 서브 샘플링 동안 발생 장기 실험 동안 유지하기 어렵다. 미세 적정 플레이트의 사용은 최대 48 내의 별도의 처리 1 ㎖의 각각의 배양에 사용되는 복제 볼륨을 가능12.65 X 8.5 X 2.2 cm 판함으로써 실험 볼륨을 감소하고 치료를 서브 샘플링하지 않고 광범위한 복제를 허용. 9-11 스크리닝 세균성 조류 공동 배양, 조류 생리 테스트 및 독소 : 또한,이 기술은 실험을 포함한 다양한 포맷에 맞게 수정 될 수있다. 조류, 박테리아 및 / 또는 공동 문화와 개인 우물로 제한 등 다양한 실험 절차에 대한 샘플링,하지만 할 수 있습니다 WATER-펄스 진폭 변조 (WATER-PAM) 형광 측정, 현미경, 세균 집락 형성 단위 (CFU) 수와는 유동 세포 계측법. 마이크로 타이 터 플레이트 포맷 WATER-PAM 형광 측정의 조합은 광 화학적 수율 및 샘플, 높은 재현성과 낮은 가변성과 다른 광 화학적 파라미터의 다수의 신속한 측정이 가능하며 실험의 과정 속에 든 대형 유리 병 또는 원추형 플라스크를 서브 샘플링 많은 함정을 피할 .

WATER-PAM의 형광 측정 수치. 물 - 펄스 진폭 변조 (PAM) 형광 측정은 형광 (엽록소 콘텐츠에 대한 프록시) 및 조류 문화의 광합성 수율 (PSII 건강)를 결정하는 빠르고 효율적인 방법입니다. PAM WinControl 소프트웨어는 원시 데이터 값의 스프레드 시트 (다음 어두운 적응 조류 시료 기본적인 파라미터이다)를 생성한다 : 어두운 적응 세포의 F 0 = 형광 <p cl...

Watch this Scientific Journal Video about A Small Volume Bioassay to Assess Bacterial/Phytoplankton Co-culture Using WATER-Pulse-Amplitude-Modulated WATER-PAM Fluorometry at JoVE.com

A Small Volume Bioassay to Assess Bacterial/Phytoplankton Co-culture Using WATER-Pulse-Amplitude-Modulated WATER-PAM Fluorometry

The goal of this procedure is to demonstrate the reproducibility and adaptability of using a microtiter plate format for microalgal screening. This rapid screen combines WATER-Pulse-Amplitude-Modulated (WATER-PAM) fluorometry to measure photosynthetic yield as an indicator of Photosystem II (PSII) health with small volume bacterial-algal co-cultures.

작은 볼륨 생물 검정은 물 - 펄스 진폭 변조 (WATER-PAM) 형광 측정을 사용하여 세균 / 식물 플랑크톤의 공동 문화를 평가하는

Conventional methods for experimental manipulation of microalgae have employed large volumes of culture (20 ml to 5 L), so that the culture can be ...

a-small-volume-bioassay-to-assess-bacterialphytoplankton-co-culture

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A Small Volume Bioassay to Assess Bacterial/Phytoplankton Co-culture Using WATER-Pulse-Amplitude-Modulated (WATER-PAM) Fluorometry

10.5K 조회수.  University of Alberta. The goal of this procedure is to demonstrate the reproducibility and adaptability of using a microtiter plate format for microalgal screening. This rapid screen combines WATER-Pulse-Amplitude-Modulated (WATER-PAM) fluorometry to measure photosynthetic yield as an indicator of Photosystem II (PSII) health with small volume bacterial-algal co-cultures.

비디오: A Small Volume Bioassay to Assess Bacterial/Phytoplankton Co-culture Using WATER-Pulse-Amplitude-Modulated WATER-PAM Fluorometry

Optimized Negative Staining: a High-throughput Protocol for Examining Small and Asymmetric Protein Structure by Electron Microscopy

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of natural proteins have a molecular mass between 40 - 200 kDa1,2, a robust and high-throughput method with a nanometer resolution capability is needed. Negative staining (NS) electron microscopy (EM) is an easy, rapid, and qualitative approach which has frequently been used in research laboratories to examine protein structure and protein-protein interactions. Unfortunately, conventional NS protocols often generate structural artifacts on proteins, especially with lipoproteins that usually form presenting rouleaux artifacts. By using images of lipoproteins from cryo-electron microscopy (cryo-EM) as a standard, the key parameters in NS specimen preparation conditions were recently screened and reported as the optimized NS protocol (OpNS), a modified conventional NS protocol 3 . Artifacts like rouleaux can be greatly limited by OpNS, additionally providing high contrast along with reasonably high&#8208;resolution (near 1 nm) images of small and asymmetric proteins. These high-resolution and high contrast images are even favorable for an individual protein (a single object, no average) 3D reconstruction, such as a 160 kDa antibody, through the method of electron tomography4,5. Moreover, OpNS can be a high&#8208;throughput tool to examine hundreds of samples of small proteins. For example, the previously published mechanism of 53 kDa cholesteryl ester transfer protein (CETP) involved the screening and imaging of hundreds of samples 6. Considering cryo-EM rarely successfully images proteins less than 200 kDa has yet to publish any study involving screening over one hundred sample conditions, it is fair to call OpNS a high-throughput method for studying small proteins. Hopefully the OpNS protocol presented here can be a useful tool to push the boundaries of EM and accelerate EM studies into small protein structure, dynamics and mechanisms.

More than half of proteins are small proteins (molecular mass &#60;200 kDa) that are challenging for both electron microscope imaging and three-dimensional reconstructions. Optimized negative staining is a robust and high-throughput protocol to obtain high contrast and relatively high resolution (~1 nm) images of small asymmetric proteins or complexes under different physiological conditions.

최적화 된 음의 염색 : 전자 현미경으로 작은 비대칭 단백질 구조 검사를위한 높은 처리량 프로토콜

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of ...

연구

환경과학

A Small Volume Procedure for Viral Concentration from Water

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to identify optimal parameters for virus concentration. Viruses can be concentrated from water using filtration (electropositive, electronegative, glass wool or size exclusion), followed by secondary concentration with beef extract to release viruses from filter surfaces, and finally tertiary concentration resulting in a 5-30 ml volume virus concentrate. In order to identify optimal concentration procedures, two different electropositive filters were evaluated (a glass/cellulose filter [1MDS] and a nano-alumina/glass filter [NanoCeram]), as well as different secondary concentration techniques; the celite technique where three different celite particle sizes were evaluated (fine, medium and large) followed by comparing this technique with that of the established organic flocculation method. Various elution additives were also evaluated for their ability to enhance the release of adenovirus (AdV) particles from filter surfaces. Fine particle celite recovered similar levels of AdV40 and 41 to that of the established organic flocculation method when viral spikes were added during secondary concentration. The glass/cellulose filter recovered higher levels of both, AdV40 and 41, compared to that of a nano-alumina/glass fiber filter. Although not statistically significant, the addition of 0.1% sodium polyphosphate amended beef extract eluant recovered 10% more AdV particles compared to unamended beef extract.

An approach was developed for identifying optimal viral concentration conditions for small volume water samples using spikes of human adenovirus. The techniques described here are used to identify concentration parameters for other viral targets, and applied to large-scale viral concentration experimentation.

물에서 바이러스 농도에 대한 작은 볼륨 절차

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to ...

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.

전체 셀 Bioreporter 접근 물 불포화 시스템에서 유기 오염 물질의 운송과 생체 이용률을 평가하기 위해

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

A Fish-feeding Laboratory Bioassay to Assess the Antipredatory Activity of Secondary Metabolites from the Tissues of Marine Organisms

Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with the goal of examining the ecological functions of secondary metabolites from the tissues of marine organisms. The result has been a progression of protocols that have increasingly refined the ecological relevance of the experimental approach. Here we present the most up-to-date version of a fish-feeding laboratory bioassay that enables investigators to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms. Organic metabolites of all polarities are exhaustively extracted from the tissue of the target organism and reconstituted at natural concentrations in a nutritionally appropriate food matrix. Experimental food pellets are presented to a generalist predator in laboratory feeding assays to assess the antipredatory activity of the extract. The procedure described herein uses the bluehead, Thalassoma bifasciatum, to test the palatability of Caribbean marine invertebrates; however, the design may be readily adapted to other systems. Results obtained using this laboratory assay are an important prelude to field experiments that rely on the feeding responses of a full complement of potential predators. Additionally, this bioassay can be used to direct the isolation of feeding-deterrent metabolites through bioassay-guided fractionation. This feeding bioassay has advanced our understanding of the factors that control the distribution and abundance of marine invertebrates on Caribbean coral reefs and may inform investigations in diverse fields of inquiry, including pharmacology, biotechnology, and evolutionary ecology.

This bioassay employs a model predatory fish to assess the presence of feeding-deterrent metabolites from organic extracts of the tissues of marine organisms at natural concentrations using a nutritionally comparable food matrix.

물고기 먹이 실험 생물 검정은 해양 생물의 조직에서 이차 대사 산물의 Antipredatory 활동을 평가하기 위해

Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with ...

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.

작은 오염 물질의 면역 학적 분석을위한 물 샘플의 자동화 된 고체상 추출을위한 간단한 방법

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

Extracting Metrics for Three-dimensional Root Systems: Volume and Surface Analysis from In-soil X-ray Computed Tomography Data

Plant roots play a critical role in plant-soil-microbe interactions that occur in the rhizosphere, as well as processes with important implications to climate change and crop management. Quantitative size information on roots in their native environment is invaluable for studying root growth and environmental processes involving plants. X-ray computed tomography (XCT) has been demonstrated to be an effective tool for in situ root scanning and analysis. We aimed to develop a costless and efficient tool that approximates the surface and volume of the root regardless of its shape from three-dimensional (3D) tomography data. The root structure of a Prairie dropseed (Sporobolus heterolepis) specimen was imaged using XCT. The root was reconstructed, and the primary root structure was extracted from the data using a combination of licensed and open-source software. An isosurface polygonal mesh was then created for ease of analysis. We have developed the standalone application imeshJ, generated in MATLAB1, to calculate root volume and surface area from the mesh. The outputs of imeshJ are surface area (in mm2) and the volume (in mm3). The process, utilizing a unique combination of tools from imaging to quantitative root analysis, is described. A combination of XCT and open-source software proved to be a powerful combination to noninvasively image plant root samples, segment root data, and extract quantitative information from the 3D data. This methodology of processing 3D data should be applicable to other material/sample systems where there is connectivity between components of similar X-ray attenuation and difficulties arise with segmentation.

A methodology for obtaining visual and quantitative root structure information from X-ray computed tomography data acquired in-soil is presented.

3 차원 루트 시스템에 대한 통계를 추출 : 볼륨 및 표면 분석에-토양 X 선 컴퓨터 단층 촬영 데이터에서

Plant roots play a critical role in plant-soil-microbe interactions that occur in the rhizosphere, as well as processes with important implications to ...

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.

방목 접지가 작은 반추 동물과 우디 작물에 커버에 대해 어떻게 조절 맛 혐오감을 만드는 방법

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.

O의 저서 교환<sub&gt; 2</sub&gt;, N<sub&gt; 2</sub작은 코어 항온 사용&gt;와 용존 영양소

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

Measuring the Flight Ability of the Ambrosia Beetle, Platypus Quercivorus (Murayama), Using a Low-Cost, Small, and Easily Constructed Flight Mill

The ambrosia beetle, Platypus quercivorus (Murayama), is the vector of a fungal pathogen that causes mass mortality of Fagaceae trees (Japanese oak wilt). Therefore, knowing the dispersal capacity may help inform trapping/tree removal efforts to prevent this disease more effectively. In this study, we measured the flight velocity and duration and estimated the flight distance of the beetle using a newly developed flight mill. The flight mill is low cost, small, and constructed using commonly available items. Both the flight mill arm and its vertical axis comprise a thin needle. A beetle specimen is glued to one tip of the arm using instant glue. The other tip is thick due to being covered with plastic, thus it facilitates the detection of rotations of the arm. The revolution of the arm is detected by a photo sensor mounted on an infrared LED, and is indicated by a change in the output voltage when the arm passed above the LED. The photo sensor is connected to a personal computer and the output voltage data are stored at a sampling rate of 1 kHz. By conducting experiments using this flight mill, we found that P. quercivorus can fly at least 27 km. Because our flight mill comprises cheap and small ordinary items, many flight mills can be prepared and used simultaneously in a small laboratory space. This enables experimenters to obtain a sufficient amount of data within a short period.

Measuring the Flight Ability of the Ambrosia Beetle, Platypus Quercivorus Murayama, Using a Low-Cost, Small, and Easily Constructed Flight Mill

We developed a low cost and small flight mill, constructed with commonly available items and easily used in experimentation. Using this apparatus, we measured the flight ability of an ambrosia beetle, Platypus quercivorus.

저가, 소형, 그리고 쉽게 생성 된 비행 밀을 사용 하 여 신들의 딱정벌레, 오리너구리 Quercivorus (무라야마)의 비행 능력을 측정

The ambrosia beetle, Platypus quercivorus (Murayama), is the vector of a fungal pathogen that causes mass mortality of Fagaceae trees (Japanese oak wilt). ...

A Flexible Low Cost Hydroponic System for Assessing Plant Responses to Small Molecules in Sterile Conditions

A wide range of studies in plant biology are performed using hydroponic cultures. In this work, an in vitro hydroponic growth system designed for assessing plant responses to chemicals and other substances of interest is presented. This system is highly efficient in obtaining homogeneous and healthy seedlings of the C3 and C4 model species Arabidopsis thaliana and Setaria viridis, respectively. The sterile cultivation avoids algae and microorganism contamination, which are known limiting factors for plant normal growth and development in hydroponics. In addition, this system is scalable, enabling the harvest of plant material on a large scale with minor mechanical damage, as well as the harvest of individual parts of a plant if desired. A detailed protocol demonstrating that this system has an easy and low-cost assembly, as it uses pipette racks as the main platform for growing plants, is provided. The feasibility of this system was validated using Arabidopsis seedlings to assess the effect of the drug AZD-8055, a chemical inhibitor of the target of rapamycin (TOR) kinase. TOR inhibition was efficiently detected as early as 30 min after an AZD-8055 treatment in roots and shoots. Furthermore, AZD-8055-treated plants displayed the expected starch-excess phenotype. We proposed this hydroponic system as an ideal method for plant researchers aiming to monitor the action of plant inducers or inhibitors, as well as to assess metabolic fluxes using isotope-labeling compounds which, in general, requires the use of expensive reagents.

A simple, versatile, and low-cost in vitro hydroponic system was successfully optimized, enabling large-scale experiments under sterile conditions. This system facilitates the application of chemicals in a solution and their efficient absorption by roots for molecular, biochemical, and physiological studies.