Can anyone identify this Permian seed from Madagascar?

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Can anyone identify this fossil fish vertebral disc?

Shoreline discovery, lighthouse beach, Chatham, MA.

09 October 2018 1,260 0 View

What are the top three largest natural gas fields in the world?

Can you estimate the reserves of each?

08 September 2014 6,058 1 View

How might one recognize tornado occurrence in the rock record?

Would shredded plant material be an indication?

03 April 2014 490 18 View

Are any American scientists, a marine vertebrate paleontology and a marine sedimentologist, interested in co-supervising a Keck study?

Research venue: Triassic strata, Nevada. Date: Next summer.

06 July 2013 2,338 9 View

What is the oldest known fossil amphipod?

Why do amphipods in general have such a limited fossil record?

05 June 2013 9,883 7 View

Is the type and only specimen of Bostrichopus antiquus Goldfuss in fact lost?

Does anyone have recent interpretations or ideas about this curious taxon?

04 May 2013 7,942 1 View

Can Neo-Darwinism (ND) today be considered a valid scientific theory?

[Tip of the hat to Darryl Smith.]

04 May 2013 3,463 34 View

Do slime molds have a fossil record?

If so, can you provide the pertinent reference?

03 April 2013 1,714 2 View

What controls the placement of parr marks or lateral bars in Salmonidae juveniles (parrs)?

Is the retention of parr marks in adult Golden Trout (Salmo aguabonita) a case of neoteny?

01 January 1970 7,144 0 View

Is life as fundamental a property of the universe as matter and energy?

This was the contention of Vladimir Vernadsky; a viewpoint that really upset A. I. Oparin.

01 January 1970 6,128 1 View

SDS page software for analysis?

I did sds page to determine the difference in protein expression between 3 types of vaccine , but i don't have scanner or densitometer available. . so i wonder if there is a software to analyze...

02 March 2021 6,270 3 View

Is there a deep reason for using the squared modulus of the wave function as the probability density of the existence of the particle?

I think we were all surprised at the first time we got to know quantum mechanics that the squared modulus of the wave function is the probability density of the existence of the particle? The role...

28 February 2021 6,282 9 View

How can I assign a velocity along one direction to CO2 molecules in a molecular dynamics simulation using GROMACS?

Dear all, I am trying to perform a MD simulation about the interaction between CO2 and a polymer. I create my model, solvate it and perform the NVT and NPT equilibration. Now I am not able to...

26 February 2021 10,014 3 View

How to plot the probability paper of Gumbel distribution using R programing?

In R-studio, there are many commands of Gumbel package. Arguments are also different. I`m asking about the alpha parameter of the Copula which must be greater than 1. If this is the one used to...

25 February 2021 5,229 3 View

Recalcitrant seed short-mid storage method?

Dear peer scientists, Ultradry storage is not suitable for recalcitrant seeds. However, theoretically, if we can stabilize the structure of the subcellular membrane, as well as glassify the...

25 February 2021 2,442 1 View

Do I need to ask permission to use pictures for my questionnaire?

I would like to use some photo from a government website for my questionnaire. But, different photo is from the different owner. So, should I just get permission from that government body or still...

23 February 2021 1,631 3 View

Is there a suitable way to confine cell attachment area inside a multi-well plate?

Are there any types of cylindrical cell culture inserts that are designed to confine cell seeding area? Say, if I'm using a 12 well plate (3.5 cm^2/well), but only want to seed cells in the middle...

22 February 2021 7,127 4 View

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The regenerated cellulose film was prepared by zinc chloride/H2O system. The zinc chloride had been washed away in the regeneration process, and the wet film which was not dried had uniform...

18 February 2021 9,538 1 View

Is it possible to use maize mature seed to do transformation for maize transgenic study?

Almost all research reports which i ever seen work on Early mature embryo for Agrobacterium mediated maize transformation. In other grass families like rice, we can use mature seed and what do...

17 February 2021 1,434 13 View

Onset of Photo Oxidation in Polymers?

Hi! I am looking for some specific information in regards to the minimum amount of UV intensity required to begin the photo degradation process in polymers. I understand each polymer is...

15 February 2021 7,703 4 View