Fishing activities can provoke volatile fluctuations in the populations they target, namely by altering the “age pyramid.” Lopping off the few large, older fish that make up the top of the pyramid leaves a broad base of faster-growing small younglings and the research team found that this rapidly growing and transitory base is dynamically unstable — a finding having profound implications for the ecosystem and the fishing industries built upon it.
Imagine a container of water with a 500-pound fish. With food, it grows a little bigger. Without food it gets a bit smaller. Imagine the same container with 500 one-pound fish. They eat, reproduce and the resulting thousands of fish boom, quickly outstripping the resources and the population crashes.
True agoraphobia is an invalidating disease but a paper by Giovanni A. Fava and associates of the University of Bologna, published in Psychotherapy and Psychosomatics, questions the excessive emphasis on panic which has been attributed in the past decade and the role of pharmaceutical industry in this attribution.
In studying the phenomenology of panic attacks, Argyle and Roth noticed that truly spontaneous attacks, not preceded by anxiety-provoking cognitions, were uncommon.
Patients meeting positive criteria for panic disorder suffered from the whole range of anxiety disorders, and a unique relationship with agoraphobia was not seen. Indeed, other diagnoses (particularly social phobia and generalized anxiety disorder) frequently predated the onset of panic. This was true also for agoraphobia.
People who score high on intelligence tests are also good at keeping time, new Swedish research shows. The team that carried out the study also suspect that accuracy in timing is important to the brain processes responsible for problem solving and reasoning.
Researchers at the medical university Karolinska Institutet and Umeå University have now demonstrated a correlation between general intelligence and the ability to tap out a simple regular rhythm. They stress that the task subjects performed had nothing to do with any musical rhythmic sense but simply measured the capacity for rhythmic accuracy. Those who scored highest on intelligence tests also had least variation in the regular rhythm they tapped out in the experiment.
There is continual debate taking place over whether organisms are the result of intelligent design or evolution. The proponents of intelligent design believe that chance and selection are too casual and slow to allow complex new properties to arise. In particular, they argue that the intermediate steps in shuffling the genes to make something new are likely to scramble the existing system and be bad for the organism, e.g., "half an eye is bad for you."
A study directed by Mark Isalan, leader of the group Gene Network Engineering and Luis Serrano, coordinator of the research programme Systems Biology and leader of the group Design of Biological Systems from the Centre for Genomic Regulation in Barcelona, Spain, says that although it may seem incredible that organisms could be able to face extreme mutation processes and gene reorganization, that is just what happens.
A new study shows that wetland regions emitted significantly less methane during glacial times while methane emissions by forest fire activity remained surprisingly constant from glacial to interglacial times.
Using novel isotopic studies, scientists from the European Project for Ice Coring In Antarctica (EPICA) say this identifies the most important processes responsible for changes in natural methane concentrations over the transition from the last ice age into our warm period.
Ice cores are essential for climate research because they represent the only archive which allows direct measurements of atmospheric composition and greenhouse gas concentrations in the past.
The risk of illegal information access, notably in money transactions, requires more and more advanced cryptographic techniques against criminals and the occasional mischevious teenager.
Quantum cryptography has been regarded as 100-percent protection against attacks on sensitive data traffic but a research team at Linköping University in Sweden has found a hole in even this advanced technology.
When an encrypted message needs to be sent over a computer network, the most difficult problem is how the key should be transmitted. One way is to literally send it by courier (which has its own security risks) or, if it's in your budget, attached to the wrist of James Bond.