jimmydasaint
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Posts posted by jimmydasaint
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As far as I recall, the evidence for subatomic particles and most molecular biological phenomena is indirect. However, at least the electromagnetic spectrum interacts with all matter and we can "see" a pellet of DNA at the bottom of an Eppendorf. How on Earth do you have conclusive proof where the whole of the electromagnetic spectrum does not allow access to it. I could hypothesise that God has ordered the angels to push apart galaxies and expand space and I can use the same evidence that you have used. Where there are galaxies with apparent less dark matter, there are just fewer angels.
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I'lll be honest and say that I don't know much about this subject. However, what would be conclusive is the actual measurement and characterisation of dark matter otherwise we might as speculate that leprechauns or unicorns cause the expansion of space/galaxies from each other.
So, IMHO, dark matter is a hypothesis that fits in with the current data but we cannot say more about it yet but speculate. Even the authors are being cautious.
QuoteThe origin of these large, faint galaxies with an excess of luminous globular clusters and an apparent lack of dark matter is, at present, not understood.
https://iopscience.iop.org/article/10.3847/2041-8213/ab0d92/meta
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Hi Charon Y,
I do try to keep with literature for my Yr 12 and 13 (A level) classes. I also try to incorporate information from papers in these lessons if it is not available in textbooks. I was not aware that live interactions between organelles have been "seen" for such a long tie. I did use fluorescent imaging and observed shedding of fluorescent proteins using a confocal light microscope many moons ago. However, I could not discern the smaller organelles (Golgi apparatus, RER etc...). I realise that parts of narratives that are incomplete are not helpful to students. However, these can be made available to bright students who are keen for extra extension to the dogma that we teach them and who can accommodate uncertainties. I agree with the misuse of titles to make each scientific discovery into a sensation.
Thank you for your reply. I will look up the latest microscopy techniques if you could point me in the correct direction.
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This is news to me. I have been teaching the textbook version for 21 years. It is about time that the textbooks are now changed. It amazes me that the new science is not incorporated into textbooks sooner. Great find and I will re-read this information. Electron microscopy has been such a useful tool to provide a snapshot of what goes on in cells but the fact that light microscopes have been developed which can provide intercellular interactions "live" is a most welcome innovation to cell biology.
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Interesting find. I did not believe it at first but then read these quotes:
Quotehe researchers’ setup resembled the French team’s, but an attached microscope allowed them to track the bacteria’s behavior. Sure enough, when the E. coli cocktail reached 10 to 20 percent bacteria by volume, swirls formed. As bacteria plowed through the water, which feels honey-thick at their microscopic scale, they produced shockwaves that buffeted their companions both near and far.
“It’s a bit like if you have a lot of stars in a galaxy and they can affect each other,” Dunkel said. Those forces encouraged local groups of swimming E. coli to align their pill-shaped bodies.
Then the motion of the plates makes that local behavior global. Dragging the top plate sends shearing forces rippling through the fluid, which in effect organize and orient the swarms.
“Without shear, the direction of swarming is random,” Cheng said. “Under shear, you get the tendency to have all the bacteria lining up in certain directions.”
Once the influence of the plates helps the bacteria settle into an average alignment, their swimming pushes on the water and generates local flows that transform the solution’s large-scale properties.
https://www.quantamagazine.org/swarming-bacteria-create-an-impossible-superfluid-20180726/
There is also a model stated here:
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.018001
As for having a motor driven by bacteria, that need warmth and a continuous flow of suitable nutrients - dream on!
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I am so glad that China, an economically developed nation, have entered the space race in such an able manner. Let's hope that they open up data and pictures to the world in an open and unselfish way. This is a great moment for the whole of humanity - not only China and let's not be small minded here. Congratulations China!
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/nice one mate. Thank you for the information.
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First of all, it is no surprise that computer scientists would consider DNA as an excellent information store. Treated correctly, DNA can be frozen and kept for potentially hundreds of years if I believe the magazine article which I scanned very quickly today. Also, there are 2 billion base pairs in the entire chromosomal content of one cell nucleus which are responsible for the encoding of roughly 21,000 genes to make a human being IIRC.
However, here is the bit where I need help. The article claimed that 9 base oligonucleotides could be used to code for short instructions and that 13 of these 9 base oligonucleotides could encode 13 trillion "words" of code (in the same way that sentences could be broken into words).
I am assuming that I read this correctly.
Not knowing coding, can someone clarify:
a) What it means by words of code and
b) What technique would allow this code to be read quickly enough for practical purposes?
In the meantime, I will hunt for the original article...
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2 minutes ago, CharonY said:
A lot (most) of mitochondrial (and plastid) DNA has been incorporated into the the host genome, though the extent can vary between different groups of organisms. Many of functions for replication are typically transferred to the host, though a few may still be retained. Typically the mitochondrial genomes lack the complete set of genes required for independent replication. There are several models and evidence of DNA transfer during the early phases of organelle origins. After establishing the core functions of organelles the rise of protein import/export functions have slowed down the transfer of the rest.
Is there a particular model which is more plausible than others about the movement of DNA from the organelle to the nuclear chromosomes? I am making an assumption here that the genes for mitochondrial replication are spread amongst several chromosomes as a "buffer" to avoid deleterious mutations, but I could be corrected...
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These are questions where I have struggled to find answers.
How did instinct arise?
How did it become "embedded" in species of animals?
Are the changes epigenetic and passed on in subtle base modifications (e.g. methylation)?
Do instincts change?
The Great monarch butterfly seems to use the sun to guide itself huge distances. I wonder if the amount of sunlight is a cue that then allows instinct to fly to "kick in"?
QuoteWe identified that the input cues depend entirely on the Sun,” explained Prof Shlizerman.
“One is the horizontal position of the Sun and the other is keeping the time of day.
“This gives [the insects] an internal Sun compass for travelling southerly throughout the day.”
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Are some of the genes for replication of mitochondria and chloroplasts found in the cellular chromosomes?
One would need to explain why the cell's chromosomes also contribute in a pivotal way to the replication of organelles and how the genes got there in the first place.
Or are the DNA plasmids found in the organelles enough for replication?
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There are two papers - one on bats, including wild bats in an uncontrolled but closely observed environment. The other is on tracking wild tiger movements in habitats fragmented by humans. These are looking at end behaviours which are measurable and provide evidence. How could you provide evidence for any behaviour which is not measurable? It would not be considered evidence by you! Evidence is only provided on the end results of behaviours surely!
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All behaviour is human behaviour? I am now worried! Did you read the two pieces of evidence that were presented by me, including the figures? I would certainly read them prior to such erroneous and hasty posting. Do you know that circadian rhythms in mammals are controlled in the same way as humans and that melatonin is similarly involved. Did you know that oxytocin receptors in some mammals determine nurturing behaviour of the young, which may be similar to humans? (I don't know if papers are out about this phenomenon in humans).
I gave you evidence = please take time to read and consider it. All behaviour is not human behaviour and we certainly get a lot of clues about human behaviour from animal studies (e.g. Pavlov's dogs).
Oh, and Science is about theory/hypothesis followed by observation and analysis. Falsification is a method for reaching objective truths; hence the carefully couched language of most scientific papers.
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I see A meta-analysis is an overall view based on other analyses by other researchers. This marks a review of trends about "nocturnality".
The original paper can be share here:
QuoteAbstract
Rapid expansion of human activity has driven well-documented shifts in the spatial distribution of wildlife, but the cumulative effect of human disturbance on the temporal dynamics of animals has not been quantified. We examined anthropogenic effects on mammal diel activity patterns, conducting a meta-analysis of 76 studies of 62 species from six continents. Our global study revealed a strong effect of humans on daily patterns of wildlife activity. Animals increased their nocturnality by an average factor of 1.36 in response to human disturbance. This finding was consistent across continents, habitats, taxa, and human activities. As the global human footprint expands, temporal avoidance of humans may facilitate human-wildlife coexistence. However, such responses can result in marked shifts away from natural patterns of activity, with consequences for fitness, population persistence, community interactions, and evolution.
http://science.sciencemag.org/content/360/6394/1232
Also, because you want evidence, there is evidence of bat behaviour being affected by streetlight illumination, here:
QuoteArtificial light puts ecosystem services of frugivorous bats at risk
https://besjournals.onlinelibrary.wiley.com/doi/abs/10.1111/1365-2664.12206
If you go straight to the figures, you will see a very clear change in behaviour when streetlight illumination is in force.
Also, there is evidence of humans affecting tiger populations by their living processes including farming:
QuoteThe 21st century has brought many conservation challenges to the fore. One very important and significant challenge that has evoked considerable scientific interest is the fragmentation of wildlife habitat. With rapidly expanding human populations and other competing land uses, areas that used to be continuous habitat have become broken and fragmented, isolating plant and animal populations contained within them. Habitat fragmentation is usually a time driven process that is innocuously initiated by human habitation or man induced habitat alteration and which eventually accelerates and results in complete isolation of once contiguous habitat. Populations thus isolated face survival pressures through increased competition for food and space and obligated risks in relation to disease outbreaks and episodic calamities such as fire and flood. Over a larger time span, species inhabiting isolated habitats also face the risk of extinction through mechanisms such as excessive inbreeding [1], [2].
The evidence is presented about six key factors which affected tiger movement (e.g. perennial water bodies) and then presented observations and analyses about each one. You can find the paper here:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0039996
They did not look at some tiger poo and make analytical statements: they performed the field work.
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9 hours ago, T. McGrath said:
First you have to have actual evidence. All they have are supposition and conjecture, and they know it. Which is why their so-called conclusions begins with "seems to..." This is nothing more than anthropomorphism, attempting to impose human characteristics and behaviors into animals they observe. It is total BS.
Wow! What a remarkably obtuse answer!
From a quick glance, this looks like a meta-analysis of 76 published studies (all of which are likely to have been peer-reviewed). The opinion reached by at maximum 76 teams of researchers who use the scientific method are likely to be better than you sitting at your computer and trying to rubbish their work. Don't talk complete garbage. Also, if you are a troll, you are likely to get caught early with your stubborn and near-sighted nonsense.
QuoteResearchers analysed 76 published studies that monitored the activity of 62 mammal species, including some that are mostly nocturnal by nature, on 6 continents. They compared the night-time activity of each species during periods of time or in regions with high human disturbance, such as during hunting season or in areas rife with roads, with their night-time activity during periods of time or in regions with low human disturbance. The findings1, published on 14 June in Science, show that most mammals become on average 20% more active at night in response to higher levels of human disturbance.
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Mathgeek, I plagiarised your post here:
QuoteIf contacting the publisher of the work containing the plagiarism is unsatisfactory, I would contact the author(s) and publisher of the original work that was plagiarized. I would also give ample public notice in forums like this one and possibly others. Errors in scholarship (including plagiarism) should be brought to the attention of a wide audience.
Just to agree with what you have written. Also, it may be possible that authors who are not expert in English would be more willing to plagiarise because they might not have the range of semantic and syntactic skills to enable them to rephrase a paragraph which appears to be perfectly written from their viewpoint. In short, help should be available to rephrase a scientific statement for people who are imperfect in written English skills (I include myself in this description due to this repetitive and word-heavy paragraph which I have just written).
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beecee, superb find which, IIRC, support the Classical Model. What are likely to be the fields of enquiry (no pun intended) for string theorists in the future?
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I don't know about the Big Bang as an act of faith. I thought the theory had pretty strong evidential basis. Big Bang evidence As a first cause, it is pretty good. And yes I base my faith on my own train of logic and inference which is my own personal opinion based on my own reasoning. I do not expect others to follow my reasoning. Like I said, I am not here to bang on a religious book - I am sharing my thoughts and opinions. If there is evidence of consciousness/soul after death then it would back my thoughts further.
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Sure. hope you are keeping well mate. All three Revelations talk about something called the soul which has a relationship with the corporeal part of existence. By its own deeds, it either elevates itself to a higher plane (Heaven) or a lower form of existence (Hell). We are also causative agents (apart from the Supreme Intelligence which caused the Big Bang) and our actions on Earth have consequences - to improve or degrade the standard of life of others. Those who give of their wealth, or time, generously raise society (and their own soul) whilst those who hoard their money and are filled with the ego of power (e.g. Pharaoh) destroy or corrupt society (and their own soul). The Revelations gave their guidance in the form of metaphor and allegory. I am not quoting these directly, it would take too long unless you want me to elaborate further?
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Just to reply to the OP. I believe in a Supreme Intelligence, call it what you will. I approach my thinking from the cause and effect relationships evident throughout the Universe. Then, I attribute the Big Bang and all subsequent events to this Supreme Intelligence that could conceivably create the forces of nature and allow the potentialities of the Universe to manifest. At some point in my chain of thinking, I come across question marks and I have doubts about the existence of this Supreme Intelligence. At this point, I need faith to believe that there is an afterlife where the elevated soul can rest after the excrescence of an Earthly existence. That faith is a strong hope underpinned by not one but 3 revelations and books that seem to give broadly the same message. However, all the above is my opinion, which I believe was requested by the OP. I am not here to bang the drum.
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In some cases they are large enough to be considered microtubes rather than nanotubes, and some researchers believe that the smaller TNTs are functionally different from microtubes. Efforts are ongoing to characterize the different subtypes of nano- and microtubes.....
Frank Winkler, a neurologist, oncologist and cancer researcher at the University of Heidelberg, discovered that the brain cancers called gliomas are full of tumor microtubes (TNTs’ larger cousins). He’d noticed these structures while watching single tumor cells grow in the brains of live mice, but he hadn’t recognized their significance. The pathologist with whom he collaborated had attributed them to defects in the preparation of the specimens. Not until Winkler and the pathologist saw these tiny tubes in living cells did they realize that the structures were real.
https://www.quantamagazine.org/cells-talk-and-help-one-another-via-tiny-tube-networks-20180423/
You probably did read about them a decade ago. IIRC, these were first discovered in 2004.
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Damn! What a shame! Have nanoparticles ever been used in vivo Charon?
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I think the assassin molecule is central to the development of Huntington's disease but that a short exposure could destroy cancers before the brain is affected. However, it is poignant that people who desperately need the treatment have to wait for Science to come through.
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These findings need to be confirmed by other labs but are stunning if they are correct. This discovery could provide a low cost solution to many cancers. Will Big Pharma pick upon this or ignore it?
QuoteThe team tested the effects of the small interfering RNAs produced by the repeated sequences in human and mouse cancer cells grown from laboratory cell lines.
They tested them in brain, breast, colon, liver, lung, ovarian, and skin cancer cells. The "assassin molecules" killed all the cancer cells from both human and mouse cell lines.They also tested the molecules' effects on live mice with human ovarian cancer. The molecules were delivered in nanoparticles that released their cargo when they reached the tumors.
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How secret conversations inside cells are transforming biology
in Science News
Posted
Thank you for the reply. I will look up each of the developments. This is fascinating material. I am sure you are an inspiring lecturer with your sheer breadth of knowledge. Please do not leave this Forum.
Have a good day.
Jimmy