5,220 Matching Annotations
  1. Oct 2018
    1. low-grade energy

      An energy that cannot be fully converted into another type of energy. Heat is considered a low-grade energy. Low-grade energies are naturally less expensive than high-grade energies such as electricity.

    1. DNA

      Deoxyribonucleic acid, or DNA for short, is one class of genetic material. It is an example of a nucleic acid molecule.

      DNA is composed of three chemical building blocks: a sugar (called deoxyribose), a phosphate group, and a nitrogenous base.

  2. Sep 2018
    1. d-dimensional

      When a vector is d-dimensional, d refers to a placeholder value that could stand for any integer, depending on how many feature values are associated with each image.

    2. hash function

      Hashing is used in computer science to reorganize large data sets (regardless of their size) into tables of fixed size. During this process, multiple data points will typically be stored in the same bin (or hash) based on how similar they are. The hash is then represented with a shortened name, or key, that takes up less storage space in the computer.

      In other words, this process helps compress the data so that a computer can use it more efficiently. It also makes it easier and faster to look up data in the table.

      ![] (https://upload.wikimedia.org/wikipedia/commons/5/58/Hash_table_4_1_1_0_0_1_0_LL.svg)

    3. feedforward

      This describes an element in a system that passes information from a source (in this case, from odorant receptor neurons) forward to another element in the system (in this case, projection neurons).

    1. bumblebee

      Not all bees are honeybees! There are actually about 25,000 different species of bees, and the European Honeybee is just one. Bumblebees (genus Bombus) can be distinguished by their fuzzy abdomens and generally larger size.

      Check out this infographic from Gould (2015) showing the different families of bees, and "bee hotspots" around the world.

      (c) Gould 2015

    2. Experimental relocation

      Also known as assisted colonization or facilitated colonization, is the act of deliberately moving a species to a different habitat, that the species would have eventually occupied given enough time or the removal of another barrier to its natural dispersal. This is in contrast to other types of assisted migrations or species introductions, where species are moved to completely new regions that they would likely never see without human intervention (e.g. the introduction of Cane Toads to Australia, or mongoose in Hawaii).

      In this instance, the authors suggest that controlled and carefully managed relocations of bumblebee colonies further north could help these species to track climate change and avoid range compressions.

    3. range shifts

      Indicates a change in where species are found. There are two ways this can happen. First, a species can move into a new place where it never used to be found. Second, a species can disappear (or go locally extinct) from a place where it used to be found.

    4. Status and Trends of European Pollinators Collaborative Project

      The Status and Trends of European Pollinators (STEP) Collaborative Project, is a multinational European initiative to "assess the current status and trends of pollinators in Europe, quantify the relative importance of various drivers and impacts of change, identify relevant mitigation strategies and policy instruments, and disseminate this to a wide range of stakeholders."

      See here for more info.

    5. Mechanisms

      The precise cause of an observed trend.

      For example, if the trend we observe is a door opening and closing by itself, the mechanism causing this trend may be the circulation of air in the hallway adjoining the door, or the mischievous actions of a sibling using a long line of transparent fishing line.

      In this study, the observed trend is the lags in range responses at species’ northern or cool thermal limits. Potential mechanisms could include a lack of host-plants in these newly-accessible regions at the northern thermal limit, or a competitor species that currently occupies this space.

    6. neonicotinoid

      A class of insecticides designed to affect the central nervous system of insects, causing paralysis and death. They are also systemic insecticides, meaning they are absorbed into every cell of a plant, and making every part poisonous. Pesticides, and neonicotinoids in particular, have been implicated as a possible reason for pollinator declines.

      Watch Prof. Richard Pywell (unrelated to this study) explain what neonicotinoids are and how they may be affecting pollinators here.

    1. dopaminergic (DA) neurons

      Cells that synthesize and release a compound called dopamine, commonly referred to as a neurotransmitter. Neurotransmitters are released at distant structures of a neuron that come into contact with close or distant cells, called synapses.

    1. Variant Description ModelThis model type is used to describe the set of features of a single productin the product line. Taking the Input Models of a Configuration Space andmaking choices where there is variability in the Input Models creates thesemodels
    2. Family ModelThis model type is used to describe how the products in a product line willbe assembled or generated from pre-specified components. Each compo-nent in a Family Model represents one or more functional elements of theproducts in the product line, for example software (in the form of classes,objects, functions or variables) or documentation. Family models are de-scribed in more detail in Section 5.4, “Family Models”.
    3. Feature ModelThis model type is used to describe the products of a product line in termsof the features that are common to those products and the features that varybetween those products. Each feature in a Feature Model represents a prop-erty of a product that will be visible to the user of that product. These mod-els also specify relationships between features, for example, choices be-tween alternative features. Feature Models are described in more detail inSection 5.3, “Feature Models”.
    1. oxidation

      In Earth's atmosphere, oxidation generally involves the reaction of a chemical species (such as a VOC) with an oxygen-containing molecule (such as ozone) or a radical (such as OH). The oxidized molecule will generally be less volatile and more water soluble than the starting material. The oxidized product may condense more easily (due to lowered vapor pressure) and form SOA in the atmosphere.

    2. three-way catalytic converters

      An emission control device that simultaneously removes three air pollutants from tailpipe exhaust by oxidizing carbon monoxide and VOCs, and reducing nitrogen oxides.

    3. secondary organic aerosols

      Small particles that are formed in the atmosphere from the oxidation (a type of chemical reaction) of carbon-containing gases such as VOCs. Later referred to as SOAs in this paper.

    1. aircraft penetrations

      As part of weather missions, certain aircraft literally penetrate to a storm's center in order to drop sensors that can transmit information about the storm back to the National Hurricane Center.

      This supplies data on environmental conditions of different storms in order to directly compare against satellite images.

      For more information, check out the "Hurricane Hunters" tab on NOAA"s website: https://www.noaa.gov/explainers/hurricane-forecasting

    2. aircraft reconnaissance

      The Department of Defense in conjunction with the National Oceanic and Atmospheric Administration (NOAA) have access to a fleet of aircraft to conduct hurricane/tropical cyclone reconnaissance, general surveillance, and research missions.

      The aircraft take measurements of geographic position, pressure height and altitude, wind direction and speeds, temperature and dew point temperature among others. These data are collected anywhere from every 30 seconds to every half hour while in flight. Up to five reconnaissance missions may go out in a day.

      This image shows some of the types of aircraft used by the U.S. to study hurricanes: Image from NOAA's Hurricane Hunters

    3. covariability

      "Covariability" is the measure of how much two variables vary together. In this case, the authors are looking at whether ocean temperatures and hurricanes vary together.

    4. significant at the 99% confidence level

      A confidence level is the probability that the value of a parameter falls within a specified range of values. In this case, the authors are 99% certain that there is an increasing trend in the number of North Atlantic hurricane and storm days.

    5. regional names

      The term "hurricane" is given to systems that develop over the Atlantic or the eastern Pacific Oceans. They are called "typhoons" in the western North Pacific and Philippines. Lastly, they are called "cyclones" in the Indian and South Pacific Ocean.

    6. best track archives

      Using satellite data it is possible to track the development and movement of hurricanes. The tracks that hurricanes progress upon are recorded and stored in online archives typically run by governmental agencies.

      For example, the National Hurricane Center compiles past track maps which allow us to look at U.S. landfalling major hurricanes from 2001-2010:

      Check out some of the other tracks and data available here: https://www.nhc.noaa.gov/data/?#tracks_all

    7. Joint Typhoon Warning Center

      The U.S. Department of Defense agency responsible for issuing tropical cyclone warnings for the Pacific and Indian Oceans does so through the Joint Typhoon Warning Center, which utilizes satellite data in order to estimate the risk of typhoons and hurricanes of the Pacific and Indian Oceans.

      To check out if any storms are currently being watched, visit their website: http://www.metoc.navy.mil/jtwc/jtwc.html

      For example from September 19th, 2018:

    8. interannual

      "Interannual" means occurring between years or from one year to the next.

      Thus this is stating that there is variability in hurricanes from one year to the next due to the effects of large scale climate conditions.

    1. Homo erectus

      An early hominin that is thought to have evolved from Australopithecus or the earliest of the Homo species. H. erectus first appeared in the fossil record about 1.9 million years ago and shares many of the traits seen in modern humans, including upright posture.

    2. 3D photogrammetric elevation model

      Photogrammetry is a 3D measuring system that uses photographs. In this study, the Laetoli footprints were measured and photographed from two different locations. Lines of sight were developed from each camera to points on the footprint. The lines of sight were then used to mathematically produce 3D coordinates of the points of interest.

    3. faults/fractures

      Faults are cracks in Earth's crust due to movement. Fractures are cracks in Earth's crust along which there is no movement. A fracture is called a fault when stresses cause the rock surfaces along the fracture to move in opposite directions.

    4. hypodigm

      A sample of a population used to infer the characteristics shared by the individuals making up the population. As it is used in this article, it refers to the fossil remains of Australopithecus afarensis used to determine the traits of of the population.

    5. palaeobiology

      Refers to the combination of two different fields of study. Paleontology examines evidence of past life from fossils and biology studies living organisms. Thus, palaeobiology examines the environmental and biological history of Earth.

    6. hominin

      Hominins are any species of early human that are more closely related to modern humans than chimpanzees.

      Hominids refers to all modern and extinct great apes, including humans, chimpanzees, gorillas, and orangutans.

      All hominins are hominids, but not all hominids are hominins!

    1. opiate

      Compounds derived from a plant known as the opium poppy. Originally these came only from natural sources, but now there are synthetic opioids. They are often prescribed for pain relief.

      Opiates are considered controlled substances due to their addictive properties. One example is heroin.

    2. dopamine

      A type of chemical messenger. Dopamine levels spike in certain brain regions in response to a reward. They also sometimes spike in anticipation of a reward.

      Once the reward is over, dopamine levels will return to normal. Cocaine stops dopamine from being cleared from the synapse by binding to dopamine transporters, so cocaine can cause a larger than normal response, resulting in greater reinforcement.

    3. skin conductivity

      Skin can become a better or worse conductor of energy/electricity when it is presented with stimuli that represent arousal. When something is physiologically arousing (e.g. scary), the electrical conductance of our skin increases because certain sweat glands become more active. Because of this, skin conductivity is an important indicator of attention and memory function.

    4. conditioned stimulus (CS)

      A stimulus that is used to trigger a learned response.

      For example, let’s say that you like ice cream, and every time you go to your aunt’s house she gives you your favorite ice cream. Now you tend to associate visiting your aunt with getting ice cream. The stimulus is visiting your aunt, and the association is getting ice cream.

    5. Slip-of-action test

      A test that allows scientists to test for habitual behavior by devaluing certain stimuli that people were trained to associate with a reward. After the stimuli have been devalued, it no longer makes sense to respond to them because there is no longer a reward. If people continue to respond, their behavior is considered habitual.

    6. DSM-IV-TR

      A guide used to classify and diagnose many different mental disorders, such as drug use and dependence.

      For substance abuse, some of the considerations are failure to perform normal tasks and functions, legal problems, and physical hazards. For drug dependence, it assesses the need for higher doses, the amount of effort and risk to get the drug, and the persistence of use. All of these must be recurrent problems to be classified as a disorder.

    7. ill-judged

      Reckless, foolish, or inappropriate. Here, the author refers to behaviors that can have consequences on health, social life (e.g. personal relationships), employment, housing, and more.

    1. DNA origami

      DNA origami is a widely studied method of self-assembly that takes advantage of the complementarity of the base pairs of strands of DNA, meaning that two specific base pairs always pair together (adenine with thymine and guanine with cytosine) by hydrogen bonding.

    2. DNA self-assembly

      Self-assembly is the spontaneous organization of preformed components into patterns or arrangements held together by reversible forces. In molecular self-assembly the components are molecules and the forces are non-covalent forces like hydrogen bonding. In DNA self-assembly, the molecules are DNA molecules.

    3. bionanotechnology

      Nanotechnology, according to the National Nanotechnology Initiative, "is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nm."

      Bionanotechnology is the use of nanotechnology to biological problems or applications such as medicine or agriculture.

      For more information on nanotechnology, why it's important, and how it is being used, visit www.nano.gov.

    4. supramolecular chemistry

      Supramolecular chemistry is the chemistry not of individual atoms and molecules which combine and are held together by covalent bonds, but of complexes of multiple molecules together which are held together by weaker, reversible non-covalent interactions such as hydrogen bonding, van der Waals forces, or electrostatic interactions (the attraction of like charges).

    1. C4 grass

      A C4 plant has light dependent reactions in its mesophyll cells and the Calvin Cycle in the specialized cells around the leaf veins. The 4-carbon organic acid, oxaloacetate is fixed from CO2. This is carried out by PEP carboxylase.

    1. (d.b.h.)

      Stands for diameter at breast height, which is the standard method of measuring tree trunks at the height of an adult's breast. It is now standardized to 1.3m above the ground.

    2. ecosystem processes and services

      Also known as ecosystem functions, these are the biological, geochemical, and physical factors that take place in every ecosystem (including water, nutrient, and energy cycles).

      Services are the benefits that people gain from nature.

    1. mollusk

      Invertebrates that are grouped together because of their unsegmented bodies, preferences for aquatic or damp-marshy habitat and usually the presence of an outer shell. Some examples are snails, octopuses, and mussels. In this experiment, they used the marsh slug (Deroceras laeve).

    2. forbs

      A general term to describe any herbaceous flowering plant that isn't a grass. In this experiment, they observed the species Achillea borealis, commonly known as boreal yarrow.

    3. extirpation

      The phenomenon of a species or organism dying off or not being found in a specific area at all while it is still found elsewhere. If the foxes were allowed to persist uncontrolled, the sea birds may die off in the Aleutian Islands.

    4. geographical information system (GIS)

      A computer system that is designed to show geographical areas in different ways and can be manipulated for the collection of data. An example is the map of fox-free vs. fox-infested islands in Fig. 1 and the map of concentrated species in Fig. 3.

    5. insular ecosystems

      A geographic region of suitable habitat for a specific organism/organisms that is surrounded by unsuitable habitat. Therefore it is isolated via environmental conditions; in this case, the habitat of both the birds and foxes are the islands on which they reside that are surrounded by the ocean.

      Both the bird species and Alopex lagopus are bound to their corresponding landscape. The foxes are trapped on their respective island because they lack the ability to swim to a new location. The birds are unable to use the same islands as Alopex lagopus because of the predation of Alopex lagopus. Therefore, both species belong to an insular ecosystem because of the unsuitable landscape around them.

    1. photosynthesize

      The process organisms use in order to produce glucose as a food source.

      Photosynthesis converts carbon dioxide, water, and sunlight, and converts it into glucose and oxygen.

    2. perturbation

      Perturbation is the act of an object or subject being "pushed" off of it's normal path. A small setback and/or a sudden change of plan.

      An example of perturbation in a biological setting would be a limb being torn off of a tree.

    3. profligately

      To do something profligately is to do spend something fast and unwisely. An example of doing something profligately is to spend large amounts of money on luxury: while being fun, you may regret it at a later time.

    4. ecologist

      Someone who studies and observes the interactions between an organism and its environment, an organism with another organism, or other non-living interactions of the environment.

  3. Aug 2018
    1. archipelago

      A group of scattered islands within a larger body of water. In this case, the Aleutian archipelago is a grouping of volcanic islands located in the Pacific ocean that are under the possession of both the United States and Russia.

    2. trophic levels

      Categorical feeding positions of groups of organisms in a food chain or web. Some common trophic levels would be primary producers (grasses), primary consumers (birds), and secondary consumers, (birds or foxes).

    1. electrophoresis

      A technique used in laboratories used to separate macromolecules based on size.The term refers to movement of charged particles in a fluid or gel under the influence of an electric field.

    2. temperature gradient capillary electrophoresis (TGCE)

      An instrument used to test for single nucleotide polymorphisms (SNP's) (common genetic variations among individuals) between DNA fragments.

    3. high-performance liquid chromatography (dHPLC)

      Denaturing High-Performance Liquid Chromatography (dHPLC) is a technique that is used to separate chemicals in a mixture. dHPLC has been used on 19 patients with auto-inflammatory syndrome suspicion to spot polymorphism in the gene MVK. This technique is a quick and low cost process in order to obtain accurate screening of the mutations.

    4. real-time PCR

      PCR is a technique in the laboratory in which short sequences of DNA are amplified. Real-time PCR has been used to rapidly detect Salmonella from cloves. It has also been used to compare three different methods to extract DNA.

    5. postelectrophoresis

      Used to increase DNA of interest. This is done by analyzing the separation patterns on the gel with the use of fluorescently labeled DNA sequencing fragments. Cutting out the desired band and then amplifying the DNA for further use.

    1. selective pressures

      Agents that condition organisms to have either a survival benefit or a disadvantage. Selective pressures drive natural selection. They can include environmental conditions, availability of food and energy sources, predators, diseases, and direct human influence among others.

    1. (AMOVA)

      The purpose of this experiment was to analyze population genetics. To achieve this, the researchers used AMOVA, or analysis of molecular variance, to detect population differentiation using molecular markers. The program was set to 10,000 permutations and they were able to obtain estimates of genetic differentiation and mean number of migrants with the GenAIEx v. 6.5 program.

    2. Linkage disequilibrium (LD)

      Refers to the non-random association of alleles at different loci in a given population. This experiment included a test for linkage disequilibrium (LD). To achieve this the researcher used ARLEQUIN v.3.5.2.2 which is an integrated software for population genetics data analysis. From this program they used the likelihood ratio test which tested for LD.