jimmydasaint
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It indicates that suicide victims often show the presence of T gondii, a parasite protoctistan organism (with several warm blooded hosts, especially the cat). T gondii can cause cell inflammation which then releases metabolites which can cause inflammation of brain tissues. People with inflammation in the brain are often seen to have committed suicide, presumably after autopsy evidence.
Previous research has found signs of inflammation in the brains of suicide victims and people battling depression, and there also are previous reports linking Toxoplasma gondii to suicide attempts," she said. "In our study we found that if you are positive for the parasite, you are seven times more likely to attempt suicide."The work by Brundin and colleagues is the first to measure scores on a suicide assessment scale from people infected with the parasite, some of whom had attempted suicide.
The results found those infected with T. gondii scored significantly higher on the scale, indicative of a more severe disease and greater risk for future suicide attempts. However, Brundin stresses the majority of those infected with the parasite will not attempt suicide: "Some individuals may for some reason be more susceptible to develop symptoms," she said.
"Suicide is major health problem," said Brundin, noting the 36,909 deaths in 2009 in America, or one every 14 minutes. "It is estimated 90 percent of people who attempt suicide have a diagnosed psychiatric disorder. If we could identify those people infected with this parasite, it could help us predict who is at a higher risk."
Although this is interesting news and is also interesting science, are the premises strong enough for the conclusion are are they weak enough for other factors to be considered?
Any comments?
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A truly inspiring find. This vindicates the fact that we share this planet with other sentient and intelligent beings who deserve our respect. However, I think the gorillas should all be trained and armed with baseball bats to chase away any more callous poachers.
Do the poachers deserve any better?1 -
True, but it might make a whole lot of things that we don't know work just fine.
Or, as Douglas Adams put it
"Imagine a puddle waking up one morning and thinking, "This is an interesting world I find myself in an interesting hole I find myself in fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!"
But what caused the rain?
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The British bee population is decreasing. Of course, there are the usual biological factors to consider - lack of food, space, competition or the appearance of new predators, or a combination of the above.
Bee experts have also speculated at the decline in bee numbers:
1.Disease from mite and virus infections. The varroa mite reached the UK in 1992 and now infests 95% of hives. Untreated bee colonies die in 3 to 4 years and even low populations of mites affects the bees' health. Other notifiable diseases include American Foul Brood and European Foul Brood have all been found in some areas of the UK .
2.Changing weather patterns. Recent wet and cold summers have prevented bees from foraging for food and have affected the time of year that forage plants appear.
3.Loss of Habitat. Flower-rich grasslands in England have declined by 97% over 60 years, with similar losses elsewhere. This has hit the UK 's bumblebees particularly hard. A range of options are available to farmers to create useful habitat but if we can all work together to create a flower-rich countryside, this would help our UK honey bees, bumblebees and other pollinating insects survive.
4.Insecticides. Insecticides used to kill agricultural pests may harm bees if these are applied incorrectly or without care.
We all need to do our part to help save our bees, whether that's by planting bee friendly plants or by supporting the work of the scientists, UK beekeepers and organisations such as the Bumblebee Conservation Trust, who are working hard to try and help the UK's dying bees
Although Dan the Gardener is not giving references to peer reviewed journals, he is giving his experienced opinion on possible causes for the decline of numbers of bees.
I am speculating that there is another cause that has not been considered - microwaves from our communications matrix called TETRA.
http://www.youtube.com/watch?v=xUc2DG9Cl64
Dr B Trower Report to the Police Federation of England and Wales
IMHO, there is sufficient evidence from Dr Trower and other researchers to suggest that humans are affected by the communication networks which propagate microwave radiation. I am speculating that it is possible that bee reproduction or physiological functions are affected by microwaves and predict that numbers of bees will decline as our communication networks expand and mast numbers increase.
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Interesting find Moontanman,
I think the researchers looked at the every interesting Hox (or homeotic box) genes. IIRC, these genes are like a molecular 'flag' which are pointers for body parts to be made by the protein generating machinery of the cell. For example, some Hox genes may be responsible for organising head development and others for development of the thorax. I think the researchers found that the whole genome duplication allowed two sets of genes to be present simultaneousy in the organism for limbs etc... One set would be conserved whilst the other would act as a substrate for evolution events and could result in a new type of limb or body structure which would then be open to selection (or extinction) by the environment.
Crow and colleagues sequenced chromosomal regions containing 19 Hox genes in the American paddlefish. Hox genes determine body shape and limb development, and have become prime candidates for detecting whole genome duplications.Whole genome duplications are game-changing events in evolutionary history that give rise to new species or novel features within a species. They occur when a series of unlikely circumstances coincide, resulting in twin copies of every gene. When this happens, one scenario that could take place is that one gene in the pair keeps its designated function while the other is either lost or takes on a new purpose.
"This extra genetic material provides the canvas for evolution to paint with," said Crow, who studies the evolution of novelty and diversity.
Two milestone genome duplications are believed to have taken place before the evolution of jawed vertebrates. Additional whole genome duplications have also taken place further down the evolutionary tree, in specific lineages or branches, but it is a phenomenon more common in plants than animals.
"Our findings on the paddlefish suggest that whole duplication is not as uncommon in animals as previously thought," Crow said.
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Hi, need a little help here. If you are assaying the pressence of a protein during several stages of development of an animal, and you see that, let's say, P1 and P8 have two bands (let's say P0 is the embryonic stage and no protein iband is seen; and the latter stages are P1 to P9) and the rest (P2 to P7 and P9) one band. What is the most probable explanation to this? And how can you verify it?
This is what I think: 1)the antibody is recognizing more than one epitope (not very specific) or 2) there is a protein with a very similar epitope (not really think is probable, also relates to 1) in some stages or 3) the protein is an oligomer and it is cleaved in some stages (early and adult).
I think 1) is the most probable and I would verify it isolating the lighter protein and re-doing the western blot. If it's positive, then the antibody is not very specific.
Any help would be apreciated, hope you can understand me.
My research is very rusty and I have to strain my memory to the days when I performed Western Blots. However, if I have understood you properly, it is possible for explanation/hypothesis 1 shows crossreactivity of the antibody to other proteins of roughly the same relative molecular mass. However, it is also possible that some protein degradation may have occurred or for an oligomer to break up during the gel electrophoresis.
A possible solution is to ask a friendly laboratory to make monoclonal antibody against P2 and, separately to P8 and then to re-do the blot or immunoprecipitations with these two on a gel.
Last time I got two bands instead of one which was expected, I am pretty sure it was down to cross contamination of antigens
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Identical twins, one egg/embryo in the uterus splits into two embryos after fertilization.
Fraternal twins, two eggs end up in the uterus and are fertilized separately. The two eggs can come from different ovaries or the same ovary... Fraternal twins can have different fathers...
I always thought that identical twins are exactly as you described (and have to be the same gender because this is an example of natural cloning). However, IIRC, fraternal, or non-identical, twins are caused by two different sperms from the same father fertilising two different ova from the mother. Due to the 'gene shuffling' that occurs in the process of meiosis before sperm or eggs are made, the fraternal twins are likely to be different in both genes and looks.
The example you gave of superfecundation where a mother can give rise to twins from two different fathers is, IMO, a much rarer event.
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This cast some light on the OP:
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Hi, to start with, I assume I am correct in this assumption, you should plot a graph of the independent variable on the x-axis and the dependent variable (what you measured) on the y-axis. If you are clear on this point, how do you work out concentrations?
If I had a 0.25 mmol/L solution it contains 0.25 mmol per 1000 ml,
so it should have 0.25/1000 mmol per each ml. Has the penny droppped yet?
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I already knew about non verbal cues forming a greater part of communication amongst people than verbal communication. Body language for business However, I was surprised to find out that shoulder body language is also revealing. For example it can reveal mood, leadership potential, or even the extent to which someone may be telling the truth. This surprised me. Any thoughts?
Both Desmond Morris, the famous zoologist, and David Givens, the famous anthropologist (see bibliography below), have talked about how wide muscular shoulders, as found on the statue of David, represent strength and virility. It is also something the Greeks particularly valued, as shown in their kouros statues with “V” shaped young men. There is probably a genetic component to this as Morris argues that we associate positive attributes to males who have that mesomorphic “V” look (wide shoulders narrow hips), we see on athletes. Perhaps this explains why women swoon when soccer player David Beckham takes off his shirt. Here the shoulders are communicating health and vitality and from an evolutionary perspective, as David Givens would say, there would be biological advantages to selecting mates with these featuresThe shoulders communicate vitality but they can also communicate dominance and hierarchy. Over my career I have interviewed a lot of criminals and I always made it a point to ask how they assessed their victims before they acted out. Over and over three things stood out, how their victims looked (frail, weak, not athletic), their overall situational awareness (never go after someone who sees you first), and their arm swing (vigorous arm movement or passive subdued). And so to a criminal, our own intra-species predators, as Robert Hare would call them, how the shoulders look is a key factor for those who seek to prey on us. As one psychopath said to me, and this was very telling, “silverbacks don’t go after silverbacks, they go after everything else.” Good point.0 -
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DNA is transcribed into RNA which is then translated into amino acids.
So, the question here is can XNA be transcribed into RNA, which is then translated into amino acids?
If I understand you correctly, RNA polymerase does not bind to XNA and transcribe out RNA.
Also, I don't understand how this XNA was made nor what the molecule looks like.
If someone could post a picture, that would be great.
I just gave the article a quick scan, but, as you know, DNA is made of a 'backbone' of sugar and phosphate, with 4 bases facing to the inside of the spiral - A, C, G and T. The XNA changes the sugar from the normal deoxyribose to other sugars, such as arabinose. So far, DNA can be made into XNA using mutated DNA polymerases. Also, mutated reverse transcriptase-like DNA polymerases can change the XNA back into DNA with excellent fidelity of base sequences. If I read the article correctly, XNA was not made into RNA.
I have found a picture of XNA which looks pretty similar to the canonical two antiparallel strands of DNA :
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Why not look at the Science News thread. XNA is cutting edge if you understand your nucleotides.
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It is exciting and cutting edge research. However, I would be cautious about the possibilities of this research. So far, the XNA's cannot be translated into amino acids. They are not recognised by conventional DNA or RNA polymerases so they do not present an environmental hazard. However, the use of these XNA's does not seem to be to generate new lfe forms but to do the following, because of their molecular tougness:
These properties mean that the XNAs are well-suited for certain applications. For decades, scientists have created short strands of DNA or RNA called aptamers, which are designed to stick to specific targets. They could act as sensors that reveal the presence of a specific molecule, or deliver drugs to diseased cells by latching onto telltale proteins. Their uses are legion, but they are fragile tools.If aptamers were built from XNAs (and more on this later), they would be tougher. However, they would still retain their key feature: they could evolve to recognise different targets. Just like RNA, many of the XNAs fold up into complicated three-dimensional structures. Alex Taylor used this property to create HNA aptamers (H is for anhydrohexitol) that recognise a protein and an RNA shape, by repeatedly selecting for the ones that form the closest fit.
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Dosage - as in mean infective dose? One of the articles cited above offered that < pfu was sufficient in a model. I dont think comments above are so relevant to herpes infection. Humoral imunity requires sufficient exposure to provoke antibody response - with that the indivudal is likely infected. As for effectiveness of macrophage and neutrophil role - suggest you look up herpes and molecular mimcry. http://www.ncbi.nlm....les/PMC1384256/
IMO, dosage, state of immune system, genetic predisposition, interactions with the environment and a host of other factors are involved in transmission of herpesviruses. Looking at the article you cited on very low doses of viruses, down to 0.1 pfu, causing infection in a model system, the authors are circumspect in their findings. Moreover, the results are for gamma herpesvisuses called Epstein Barr Virus and Kaposi sarcoma-causing herperviruses. IIRC, these are commonly transmitted by saliva and not by bottoms on toilet seats. Additonally, the virus was administered by intraperitioneal injection and not swabs. Did you know that?
Following intraperitoneal (i.p.) infection with 106 PFU of γHV68, the frequencies of reactivation were 1 in 1,000 for peritoneal cells and 1 in 9,700 for splenocytes at 16 days postinfection (Fig. 1A). Notably, these frequencies did not differ more than fourfold over infecting doses ranging from 0.1 to 106 PFU and were similar to data previously published for 106 PFU (25). That infection was detectable with doses as small as 0.1 PFU (as determined by plaque assay on 3T12 cells) likely reflects the fact that mice are a more sensitive indicator of infection with γHV68 than are cultured 3T12 fibroblasts.I could not find your references on effectiveness of neutrophil and macrophage in viral infection but the large human population would seem to indicate their role in success, as the first arm of the immune system, and in contributing to the survival of the human species.
The second study that you cited did show shedding in sites that could possibly be exposed to toilet seats. However, given the sheer variability of social, environmental and genetic factors, it is very difficult to establish if herpesvirus could be spread this way.
Participants attended individual educational sessions on HSV-2, were shown pictures of both typical and atypical lesions, and were instructed to inspect the genital region for lesions daily and obtain swabs of their genital area, including any genital lesions. Men were instructed to swab first the penile skin and then the perineum and the perianal areas.9 Women were instructed to insert the swab into the vagina and then swab the vulva, the perineum, and the perianal areas.10 Swabs were placed into vials containing 1 mL of polymerase chain reaction transport medium and stored at 4°C until laboratory processing. Each participant kept a diary of genital lesions and symptoms.10 Participants visited the clinic every 2 weeks for symptom review and collection of swabs0 -
The OP is a bit problematic IMHO. Although persistence of bacteria and viruses on surfaces such as door handles and banisters etc... has an evidential basis, we still have to consider the important dosage effect of the virus in question and also skin and mucosal immunity as well as the state of the immune system of the person sitting on the seat, amonsgst other factors. The answer would have to be that the chances are high against infection from a toilet seat.
Humans have a very powerful non specific arm of the immune system (for example macrophages and neutrophils) which are capable of ingesting foreign materials. Additionally, the specific arm of the immune system, exemplified by the production of antibodies such as IgA and IgM are also associated with mucosal/skin surfaces, IIRC, as a powerful deterrent to the internalisation of viruses.
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It is cool but seems to be a model system in use. Although the ease with which an embryo can be split by a wave means that coral can respond quickly to reef damage quickly. Interesting.
When corals mass spawn at night on the Great Barrier Reef, the rough waves that often accompany this event could help maximize their breeding success, according to new Australian research published in Science on March 1.After fertilization, the eggs begin to divide, forming larvae overnight that may be dispersed by ocean currents prior to settling. However, unlike most other marine invertebrates, the embryos are not shielded by a membrane, making them vulnerable to fragmentation.
“As the early-stage embryo develops, it divides into a cluster of cells,” said study co-author Andrew Heyward at the Australian Institute of Marine Science (AIMS) in a press release. “Because this ball of cells lacks a protective outer-layer, we wondered whether subjecting them to a little turbulence might cause them [to] break up.”
The researchers recreated the effects of the smallest waves on the reef by pouring embryos into another vessel containing seawater from about a foot (30 cm) above.
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Ah, I think that I see the misunderstanding, thanks questionposter, I wonder if jimmydasaint has the same misunderstanding.
Do you think that I meant that mutations are only ever either beneficial or detrimental according to evolution, and never neutral?
Again, another excellent answer. I would consider that most mutations are neutral. However, I did not read the last paragraph of one of your responses and just wanted to point out that there is a large number of human mutations that do affect fitness and decrease the opportunity for successful reproduction, in the current environment.
For example, there are a number mentioned in wiki:
Wiki List of Genetic Disorders
That is all I meant by 'balance'. Of course you have to be candid about the contribution that those affected could make to the gene pool and define evolutionary fitness.
Of course slight variations in skin and hair colour can be determined to be beneficial or detrimental evolutionarily wise. For example all it takes is for the majority of sexual partners to have a penchant for a slightly different hair, skin, or feather (think peacocks and birds of paradise) colour for the frequency of the alleles for that particular mutation to increase in the population over the generations via sexual selection. That, in a nutshell is how evolution via sexual selection works. Also with other types of selection all it can take is a very slight phenotypic difference to effect an evolutionary change.I don't know how relevant this article is, but it suggests that the skin colour of the Europeans may have evolved to increase the 'fitness' to make vitamin D in light-deprived areas.
According to a team of researchers from Copenhagen University, a single mutation which arose as recently as 6-10,000 years ago was responsible for all the blue-eyed people alive on Earth today.
The team, whose research is published in the journal Human Genetics, identified a single mutation in a gene called OCA2, which arose by chance somewhere around the northwest coasts of the Black Sea in one single individual, about 8,000 years ago.
The gene does not "make" blue in the iris; rather, it turns off the mechanism which produces brown melanin pigment. "Originally, we all had brown eyes," says Dr Hans Eiberg, who led the team...
It is only in Europe that you will find large numbers of blondes and redheads, brunettes, pale skins and olive skins, blueeyed and green-eyed people living together in the same communities. Across the rest of the world people are almost uniformly darkhaired and dark-eyed.
Why this should be remains unknown, and in particular how such mutations can have arisen so quickly since Europe was colonised by Africans just a few tens of thousands of years ago.
One theory is that Europe's cold weather and dark skies played a part. Fair skin is better at making Vitamin D from the 8 per cent of the world's population have blue eyes weak sunlight found in northern latitudes.
and Link to Paper
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I accept the point that the market does dictate wages paid to players in team sports and that male team sports generate far more income than female teams. I accept also that males are physically stronger than females and that this physical disparity means that women have very little chance of winning a man's sport generally. Males also prefer watching male sports presumably. They like watching other men get hot and sweaty. Fine.
Would you then agree that women are equal in educational and employment opportunities? I would argue that women are badly under-represented in academic occupations, in government and in becoming CEO's of well-known companies - but that is a separate issue altogether, and deserves a separate post.
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You gave an excellent answer to the previous few posts. However, IMO, many mutations are either neutral or downright deleterious. I believe there should be caution and some balance when human mutations are mentioned Halucigenia.
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What about Huntington's Disease, Motor Neuron Disease, Alzheimer's Disease and Polydactyly?
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How equal do I want it? Equal prize money for starters. I was making the point initially that there is no equality between genders in sport despite our proclamations about equality for women generally in society. Nevertheless when it comes to prize money, women get paid far less for winning golf, and, to my knowledge, tennis tournaments, in the past (which are now awarding equal money). What is the underlying silent script? It seems to say that women's sports are less worthy, and that, to my mind, is unfair.
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Well, I have some poetic and some interesting answers. However, is it possible that we are talking about psycopathy as a lack of empathy towards an individual and we can then classify this as being evil. I take that it is not easy to distinguish evil people from those that have empathy, by conversation or by a questionnaire of some sort, otherwise it would be easy to disengage socially from these people. I have a professionally qualified friend who quite openly wishes to take a baseball bat to his managers and has said that he has, in his head, rehearsed a routine where he can 'bash these people to death'. He also has problems with explosive anger. Are these signs of psycopathy or evil. He is also a committed Christian, which implies to me that the environment can control or ameliorate the natural feelings to get even and to kill others that wrong you.
Any thoughts?
And death shall have no dominion.Dead men naked they shall be one
With the man in the wind and the west moon;
When their bones are picked clean and the clean bones gone,
They shall have stars at elbow and foot;
Though they go mad they shall be sane,
Though they sink through the sea they shall rise again;
Though lovers be lost love shall not;
And death shall have no dominion.
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Just a thought here. By evil, I mean are there people who are born with a complete lack of empathy towards other individuals and therefore are completely selfish and self-serving? If so, the concern is that can we blame these people for their subsequent actions or do we contextualise their evil with their particular genomic profile?
In short if you are born with the genetic profile of a murderer and then go on to murder people. can you claim that your genetic predisposition can provide suitable extenuating circumstances?
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Why is the Northern Hemisphere Colder Than the Southern?
in Earth Science
Posted · Edited by jimmydasaint
This is a brief question exposing my lack of knolwedge on this issue. However, on average, I am considering that most of Northern Europe (including e.g. Sweden, Norway and Scotland) is colder than Southern Europe closer to the Equator. However, why is it that Australia, New Guinea and New Zealand are considered hot countries when they are close to the South Pole?
I would love to know the answer.