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To evaluate interaction is one of the most important objectives of fatorial experiments. The use of less rigorous level of significance for interpretation of the interaction, maybe it can catch important effect. In some situations, even without significant interaction (p≤0.05), the decomposed interaction demonstrates the differential effects of levels of factor B for each level of factor A or vice versa.
Could I use p≤0.15 for the interpretation of the effect of the interaction, keeping the usual p≤0.05 for the isolated effect of factors and comparisons? Is it adequate for analyzing agricultural field experiments?
Do you have current article recommendations on this topic?
Thanks!
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It's interesting than you seem to consider 0.05 a "rigorous level". It is more likely to get p<0.05 by pure noise than it is to toss a pair of 6 with two dice. And this happens quite often. Seeing a publication making a point of the fact that a player seems to have some supernatural control about the outcome of dice tosses because he tossed a pair of 6 is anything but "rigurous". You may find this a stupid comparison because the hypothesis is obviousely nonsense. But this is relevant. The statistical significance is independent from the scientifc context, but its interpretation is not. A level of 0.05 is already quite loose or permissive and requires some solid theoretical context that explains why the observed effect should make sense. A "less rigorous" level would require even more than that. It might be acceptable in a context of several experiments with all coherent results.
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All the externally aided projects which are funded have to go through rigorous checks and appraisals on a continued basis depending on the work plan. In order to meet the timeline the scholars engaged under the projects has to follow the deadlines. How should the scholars be made to work?
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Make a timeline for completing the tasks and accuracy. An coding control sample and other sample must be placed in the laboratories
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Need a device for field experimentation by which temperature of fruit pulp of developing fruit can be measured by non destructive means especially for fruits like mango, banana etc.
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Infrared thermometer used to measure temperature of fruit pulp of developing fruit on plant by non destructive method.
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Is there any method (optimization) for time delay change between the time of the sample collection and when it is assessed/examined?
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A new method to reduce the number of time delays in a network
Time delays may cause dramatic changes to the dynamics of interacting oscillators. Coupled networks of interacting dynamical systems can have unexpected behaviours when the signal between the vertices are time delayed. It has been shown for a very general class of systems that the time delays can be rearranged as long as the total time delay over the constitutive loops of the network is conserved. This fact allows to reduce the number of time delays of the problem without loss of information. There is a theoretical lower bound for this number that can be numerically improved if the time delays are commensurable. Here we propose a formulation of the problem and a numerical method to even further reduce the number of time delays in a network. Source: Scientific Reports | 7: 2744 | DOI:10.1038/s41598-017-02978-5
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Dear all,
we are going to use the PAM-2500 to measure chlorophyll fluorescence parameters in grapevine. The measurements will be conducted outside, therefore we want to keep it simple, but of course efficient in data aquisition. Therefore dark adaptation is no option for us, bu the instrument has many different functions to circumvent this problem.
I have the following questions:
1. the field screen with the Y(II) measurment provides no light acclimation step with standard actinic light, just a light puls. do you think a standardized acclimations to actinic light is necessary?
2. Fo´is measured under field sceen after the light sat puls and a short period of FR. Is this similar to the FR+Y option?
3. do you use default light intensities? we are working with grapevine
many thanks
Michaela
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http://www.walz.com/products/chl_p700/pam-2500/downloads.html, YII will vary with light intensity and a step curve can be made with portions of the leaf shaded by a net or a filter 5 min before taking reads. Clips with a frame holder can be made from spare. Further questions are on manual, care in recording temperature water status and chl density, with the best
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I want to create range of light intensities in the 2×5 m plots under field condition. Which materials can be suitable for this purpose?.
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Dr. Ali Reza Yousefi,
I consider that there is no best way to change light intensity under field conditions. There are various materials to do this like shading nets and screens as already pointed out by Dr. Bongi and Dr. Graham, respectively. I agree strongly with Dr. Graham if the point is the modification of light intensity. The suitability of each available material in field conditions depends primarily on its resistance to extreme weather conditions e.g. hail. In an open field, another problem is the greater variability of a number of variables, in general, in relation to a glasshouse and the effective control of this variability.
The attached publication, with regard to shading by shading nets, may be useful for your research.
Best Regards
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If someone have phenotypic data that could be applied to the  methodology suggested in this paper that could be great as this method could have several applications in field and experimental works
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Jeg har også en del data, som metoden evt. kan testes på. Kontakt mig på vibeke.simonsen@gmail.com
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I am currently working on evaluating the effects of climate change on marine plankton using a mesocosm facility. I have some queries
The capacity of my tank is 2000 L - Indoor facility
1. Do I need a wave maker for recirculation in the tank or is it enough if I use a high capacity blower (e.g. 80 HP).
2. What kind of instruments should I used for CO2 diffuser?
3. I am planning to run one set of experiment for 20 days, the total capacity of seawater will be 2000 L, Do I need a separate recirculating system?
4. I will be drawing around 10 L for various analysis on alternate days for a period of 20 days.. how much will this effect the total volume ? I don't think refilling is a good idea, kindly suggest me some alternative.
5. What are the general problems that we could face while using a mesocosm facility?
Thank you
Regards
Vinitha
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Hello Vinitha, 
If i may suggest some literature that you will find very useful and will answer some of your questions:
The Guide to Best Practice in Ocean Acidification Research:
A methods review from Dr. Cornwall et al., 
1) You do not really need a wave maker, but a recirculation pump, unless of course wave motion is a parameter that you want to add to your experiment;
2) For CO2 diffusion it is advised to use an atomizer, but strongly depends on what kind of tank (e.g. if your tank is closed or open) and on your CO2 injection systems. Also in your case with a 2000L tank you will need A LOT of CO2 to maintain high CO2 to simulate future oceans conditions, that will be hard (but not impossible) and costly to accomplish;
4) if you have a closed system, you have to consider refilling... using UV filtered seawater, or a synthetic one that you can DIY
5) there are many problems that you face, and these are similar to the ones that aquarist and aquaculture professionals experience, so you will find a lot about proper methods of cultivating planktonic communities. For example, water changes, proper nutrients concentration, oxygen depletion, in your case also CO2 diffusion, temperature maintenance, proliferation of unwanted organisms... etc etc... 
personal advices:
I just wonder why you need so much volume, since you need to replicate your experiment, there are simpler (and easier treated) tanks that are designed for planktonic communities, for example a very very simple one that you can build yourself: http://www.reefkeeping.com/issues/2002-07/ds/images/image002.jpg 
Hope it helped you a bit, this is as far as i can go with the information you gave, 
Regards, 
Fabio
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In reference to the recent Science article, "The valley Hall Effect in MoS2" there is a Hall voltage developed when monolayer MoS2 is illuminated by circularly polarized light. There are no external sources of magnetic field in this experiment and yet there is a hall voltage.
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Its basically like the motion of the electrons induced a magnetic-like field( the Berry curvature), and electrons/holes feels a force in this field which caused them move to the edges. There is a RMP paper Berry phase effects on electronic properties, I think it will serve you well.
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I am trying citations related to the idea that "diversity begets diversity." In particular, I am interested in finding examples of experiments where diversity has been manipulated at one trophic level, and then diversity of lower or higher trophic levels was measured as a response variable. I am not interested in experiments that have only manipulated diversity as presence-absence. I am more interested in experiments that have multiple levels of diversity. I'm looking for experiments like these: 
Haddad, N.M., Tilman, D., Haarstad, J., Ritchie, M., Knops, J.M., 2001. Contrasting effects of plant richness and composition on insect communities: a field experiment. Am. Nat. 158, 17–35. doi:10.1086/320866
De Deyn, G.B., Raaijmakers, C.E., van Ruijven, J., Berendse, F., van der Putten, W.H., 2004. Plant species identity and diversity effects on different trophic levels of nematodes in the soil food web. Oikos 106, 576–586.
Ogada, D., M.E. Gadd, R.S. Ostfeld, T.P. Young and F. Keesing. 2008. Impacts of large herbivores on bird diversity and abundance in an African savanna. Oecologia 156:387-397.
Thanks for any leads!
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Hi Grace,
I know of the study by Scherber et al. looking at the diversity of different species groups in response to a plant diversity treatment. This may be of interest for you.
Scherber, C. et al. (2010) Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment. Nature 468, 553-556.
All the best,
Christian
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We conducted study to check the impact of microbial inoculations, water level variation and addition of organic amendments on soil structure and their indirect impact on root development and growth. Now the problem is my software (Smartroot) is not working properly and other softwares (WinRhizo, RootEdge etc) are not in my access. If someone has an advice as well as some sort of other software then please recommend.
Waiting for your reply
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Please check similar software on the right side of the page.
If EZ-Rhizo works for you, then good. All the best
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Until recently, the Eotvos experiment (or the equivalence principle) has NEVER been validated under the strong magnetic field. And the strong magnetic field may be one possible factor to impact evidently the Eotvos experiment, resulting in the variation of gravitational mass.
On the other hand, it is necessary to validate the Eotvos experiment in the strong magnetic field. 1) When the distribution of strong magnetic field is uniform, the variation of magnetic flux density will alter the gravitational mass. 2) In case the distribution of strong magnetic field is non-uniform, the variation of magnetic flux density will result in not only the alteration of gravitational mass but also the emergence of strength gradient force.
As a result, the strong magnetic field must break the existing state of force equilibrium, transferring the existing equilibrium position of the neutral particle. Furthermore, on the basis of existing Eotvos experiments, it is feasible to validate the Eotvos experiment via applying strong magnetic fields in the experimental technique.
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I don't see what you mean by change of gravitational mass because of magnetic fields (at least not without utterly unobtainable magnetar like magnetic fields), but I can certainly see how even minute magnetisation effects in a strong magnetic field (by earth standards) could provide additional torques on a suspended test mass that would make Eotvos type experiments even more difficult than they are without a magnetic field. I would be interested to know how you think strong magnetic fields can validate the Eotvos experiment.
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Anyone have an idea about the long term field experiment (LTFE) with PGPR combination in worldwide
 We want to start LTFE with PGPR any reference experiment like this or any idea to start like this,, 
Please provided suitable suggestions 
Thanks 
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Long term field experiment can be used by native microbial strain which can be inoculated at seed treatment, seedling dip and booster dose at regular intervals till the completion of experiment taking into the consideration of OD of culture.
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I am basically an Agribusiness professional, interested in Random Field Experiment projects. Kindly help me to start with this
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Dear Anderson,
I am ready with my draft proposal. Kindly, provide your email id so that I can send the same for your review.
Dr. Rams
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I would like to compute light interception and use efficiency for cassava growth. I got data from a field experiment conducted in a location where solar radiation nor sunshine hours data were not available. Only daily minimum and maximum temperatures and rainfall data were available. What is the best way to estimate daily solar radiation in this case? Computer programs and scientific references are welcome! Thanks for your suggestions
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Guillaume, you might want to look at NASA power to see if they have data for your location (see power.larc.nasa.gov, under the section Access Data, select Agroclimatology); and also the improved Bristow-Campbell approach to estimating solar radiation based on temperature and rainfall. I'll send you some references. Best
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Field experiment.
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I recommend the small portable rainfall simulator option in order to obtain comparative field data.
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I made crosses in 6 varieties of tomatos according to half diallel fashion in a field experiment. In this way I attempted a total of 15 cross combinations. I got sufficient fruit setting in crossed flowers but the number of seeds were less i.e. 20-30 seeds per tomato fruit. On the other hand there were up to 100-150 seeds in selfed tomato fruits. My question is that when I made crosses with sufficient pollen grains, I got less seeds per fruit, what could be possible reasons for less seeds in crossed fruits.
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Dear Rakesh,
I perform about 100,000 pollination per year on potato flowers and found that there are some things to keep in mind.  Use a lot of FRESH pollen.  Apply it to the protected stigma generously.  Warm and dry environments shed great pollen but it counters fertilization/pollen tube growth on emasculated flowers, due to styles becoming dehydrated.  Obviously, there are also incompatibility issues between genotypes.  My suggestion is to perform  the crosses in a humid environment and dip the emasculated flower in a 2ppm mixture of 2,4-D with surfactant - this should encourage fruit set and possibly pollen receptivity.  Enclosing flowers in a small bag increases humidity, but keep the bag out of the light so as not to "cook" the flowers.  Remove the bag after 24 hours.  Potato pollen fertilizes the eggs usually within 12 hours.  I assume the tomatoes would act the same. 
I hope this is useful for your studies.
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I intend to measure N release rate from broadcast applied controlled release fertilizers. I expect to explain other plant and soil variables according to different release rates. All methods I could find are based in fertilizers incorporation or small pots laboratory incubation. I would like to do that directly in the field. Has someone seen or done a paper with such evaluation?
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I have not seen this done in the field, though am interested to see what others post.  I would go for a very straightforward method of sampling the rooting depth (typically 30cm) and looking at total N, inorganic N forms (KCl extraction), and mineralization rates (KCl extraction seperated by a short times), and doing all three of those as a time series.  From that you should have total N and total inorganic N at different times, as well as the conversion rate or organic N to inorganic N.  From that time series I think you could calculate based on pool balances all that you need to know.  Maybe not the cleanest method, but relatively cheap and easy. 
Again..interested to hear what others have to say.
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I want to use a mobile eye tracker for some real world experiments and still trying to search for the best option for it. Any opinions or experiences about this device?
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Hi, I used Positive Science eyetrackers when I was a Products Researcher at Procter & Gamble. It's the best mobile eye tracker on the market if keeping every eye tracking movie as a usable data source is important to you. It's the most flexible & has the best tools for getting an eye tracker to work, once you get the hang of the software. In that arena, it easily outperforms systems that are 3-4 times more expensive. I've used Tobii, ASL, SMI, and Eyelink, and the Positive Science Ultraflex is the absolute best at delivering accurate tracking in a wide variety of conditions. I've used Positive Science eyetrackers in grocery stores, in consumers' homes, even in rural india - it works everywhere.
Coding data is really the big problem for all head mounted eye trackers. There are some eye trackers that have provided coding solutions, (dikablis, Tobii, ASL) but those have largely come at an insane cost, and they also deliver a terrible track. The Dikablis,. for example, costs $60,000 and puts its scene camera in the middle of the forehead, unnecessarily increasing parallax error. The Tobii glasses just plain don't work about 70% of the time. When they do actually work, and when you have put their markers on everything, it's OK, i guess, but you never really know when they're working until after you're done, and they also cost $45k. (last i checked, which was a few years ago). Also, if someone isn't tracking in a Tobii, it's a complete black box, so you just have to give up & try a new person. ASL has a reasonably good eye tracker, and they are doing a lot to improve their motion matching algorithms, but there are still risks where you can lose the entire video if someone moves their head too fast & smears the image (from what I can recall, I last tested their technology in 2010)
For full disclosure, I worked with Positive Science and with the Rochester Institute of Technology to develop their coding solution, Semanticode. This is mostly because the other solutions on the market were so bad. I've divested all financial interests and receive no money from the licensing of the software, however. But I'll freely admit bias when it comes to the hand-coding solution - I think it is the best way to code fixations for real-world eye tracking experiments, mostly because you still need humans to categorize fixations, unless you're running Tannenhaus-esque visual world experiments, or something like that.
So, just one opinion, but I think the Positive Science is best in class at delivering an accurate track (if you are willing to learn the extensive tools that they have for tracking gaze), and that it has the most accurate coding solution, given that the other trackers (like Tobii and Dikablis) are so ungodly terrible at, well, eye tracking. SMI had an interesting moveable ROI tool in their software, but their hardware are also high in cost, and you probably aren't saving yourself a lot of time by coding videos that way vs. coding them in SemantiCode. Positive Science way outperforms SMI on cost.
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When we use the dirac delta function to solve the paradox of divergence of a 1/r^2 field, we say that divergence of the field is infinity at r=0 as delta function reaches infinity at r=0 which means that there is infinite flux passing through a minute volume. But since it can be mathematically proven that a point charge is nothing but a uniformly charged solid sphere with a very small radius, the electrostatic field at r=0 is 0, which contradicts the result obtained using dirac delta function. Why?
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First, the field going as 1/r^2 (and naturally diverging at r=0), corresponds to
a classical model and describes the field in the vacuum, that is, outside the point charge.
Second, the Dirac's delta is not a function but a distribution. Distributions have such a 'bizarre' behavior because they are defined to be finite under integration.
Finally, that is not true that a point charge is exactly an sphere with small radius. The issue here is precisely, that a point charge is a mathematical point, that is, has no measure. That is precisely why we describe point charge densities by using Dirac's deltas: to have finite fluxes! So there are no paradoxes. It is just a convenient description to treat classically objects (particles and fields) that are quantum in their very essence.