Strain directs spin waves

It is becoming harder to respond to the demands of the rapidly-growing information society due to failures caused by increased chip temperatures in the ever-more integrated chips used by the latest electronic devices based on semiconductor materials. Therefore, the development of spin wave integrated circuits (ICs), which can perform information processing with minimal generation of heat by manipulating spin only rather than moving electrons, has been gaining attention. Within this field, spin waves transmitted through a magnetic insulator film have the advantage that energy loss is small and long-distance transmission is possible. On the other hand, in order to transmit spin waves within a magnetic insulator film, it was previously necessary to attach relatively large permanent magnet parts to the magnetic insulator film, which was a problem for realizing spin wave ICs.

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Memory molecule limits plasticity by calibrating calcium

The brain has an incredible capacity to support a lifetime of learning and memory. Each new experience fundamentally alters the connections between cells in the brain called synapses. To accommodate synaptic alterations, certain areas of the brain are highly plastic, meaning that have the ability to adapt to incoming information. Within an important brain structure for memory, the hippocampus, reside some of the most plastic cells in the entire brain, utilizing the process of synaptic plasticity to remain primed and flexible.

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Long-term study reveals one invasive insect can change a forest bird community

Eastern hemlock forests have been declining due to a non-native insect pest, the hemlock woolly adelgid. A new study from The Condor: Ornithological Applications presents some of the best long-term data showing how the decline of a single tree species (eastern hemlock) leads to the disappearance of birds specialized to those trees. The data also indicate birds associated with non-hemlock habitat features (deciduous forest, woodland edge, and shrubs) are spreading into former hemlock forests. A single insect species has led to a less diverse bird community across this landscape.

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Controlled nano-assembly

DNA, the carrier of genetic information, has become established as a highly useful building material in nanotechnology. One requirement in many applications is the controlled, switchable assembly of nanostructures. In the journal Angewandte Chemie, scientists have now introduced a new strategy for control through altering pH value. It is based on ethylenediamine, which only supports the assembly of DNA components in a neutral to acidic environment — independent of the base sequences and without metal ions.

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Birds play the waiting game in tough environmental conditions

Every animal’s ultimate goal in life is to generate offspring to pass on its genetic material to the next generation. But sometimes, resources are scarce and the task of reproduction is too difficult or risky. If resources are limited and tough to find, reproductive efforts may fail anyway. In these situations, it may be in an animal’s best interests to not defend a territory or to breed at all, but rather to focus its efforts on surviving to the next breeding season. Biologists refer to individuals without a territory during the breeding season as ‘floaters’. A new study from The Auk: Ornithological Advances presents some of the best evidence on how changes in environmental conditions, specifically droughts, impact the social and reproductive behavior of birds.

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Weird World 

Chimpanzee calls differ according to context

Studies examining animal alarm calls suggest species which require different escape responses for different predators are more likely to have correspondingly different alarm calls, facilitating appropriate escape responses from receivers. However, what causes calls to diversify in less urgent contexts is little examined. “To address this, we examine a quiet contact vocalisation of chimpanzees, the ‘hoo’,” says Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology. “We found that chimpanzees have at least three acoustically different ‘hoo’ variants, each given in a different behavioural context: alert, travel and rest.”

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Men take shortcuts, while women follow well-known routes

When navigating in a known environment, men prefer to take shortcuts to reach their destination more quickly, while women tend to use routes they know. This is according to Alexander Boone of UC Santa Barbara in the US who is lead author of a study that investigated the different ways in which men and women navigate. The research is published in Springer’s journal Memory & Cognition.

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