Examples of nucleus accumbens in the following topics:
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- It is highly interconnected with the nucleus accumbens, the brain's pleasure center, which plays a role in sexual arousal and the "high" derived from certain recreational drugs.
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- A different movement disorder, called hemiballismus, may result from damage restricted to the subthalamic nucleus.
- The role in motivation of the limbic part of the basal ganglia—the nucleus accumbens (NA), ventral pallidum, and ventral tegmental area (VTA)—is particularly well established.
- The inputs from the cortex and thalamus to the striatum and subthalamic
nucleus are glutamatergic, but the outputs from the striatum, pallidum, and
substantia nigra pars reticulata all use GABA.
- Dopamine is used by the
projection from the substantia nigra pars compacta to the dorsal
striatum and also in the analogous projection from the ventral tegmental area
to the ventral striatum (nucleus accumbens).
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- Some of the most important parts of the brain's reward center include the nucleus accumbens, the VTA, and the frontal cortex.
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- Found within eukaryotic cells, the nucleus contains the genetic material that determines the entire structure and function of that cell.
- One of the main differences between prokaryotic and eukaryotic cells is the nucleus.
- The nucleus stores chromatin (DNA plus proteins) in a gel-like substance called the nucleoplasm .
- Lastly, the boundary of the nucleus is called the nuclear envelope.
- The nucleus is the control center of the cell.
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- A nucleus weighs less than its sum of nucleons, a quantity known as the mass defect, caused by release of energy when the nucleus formed.
- This mass, known as the mass defect, is missing in the resulting nucleus and represents the energy released when the nucleus is formed.
- As the size of the nucleus increases, the strong nuclear force is only felt between nucleons that are close together, while the coulombic repulsion continues to be felt throughout the nucleus; this leads to instability and hence the radioactivity and fissile nature of the heavier elements.
- This graph shows the nuclear binding energy (in MeV) per nucleon as a function of the number of nucleons in the nucleus.
- Notice that iron-56 has the most binding energy per nucleon, making it the most stable nucleus.
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- Pair production refers to the creation of an elementary particle and its antiparticle, usually when a photon interacts with a nucleus.
- Below is an illustration of pair production, which refers to the creation of an elementary particle and its antiparticle, usually when a photon interacts with a nucleus.
- In nuclear physics, this reaction occurs when a high-energy photon (gamma rays) interacts with a nucleus.
- The nucleus in the process carries away (or provides) access momentum.
- Describe process of pair production as the result of photon interaction with nucleus
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- Because a eukaryotic cell's nucleus is surrounded by a membrane, it is often said to have a "true nucleus. " Organelles (meaning "little organ") have specialized cellular roles, just as the organs of your body have specialized roles.
- Typically, the nucleus is the most prominent organelle in a cell.
- Eukaryotic cells have a true nucleus, which means the cell's DNA is surrounded by a membrane.
- The nuclear envelope is a double-membrane structure that constitutes the outermost portion of the nucleus.
- The nucleoplasm is the semi-solid fluid inside the nucleus where we find the chromatin and the nucleolus.
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- A nucleus can either by a relatively compact collection of neurons or a distinctly identifiable group of neurons spread over a large area.
- In neuroanatomy, a nucleus is a brain structure consisting of a relatively compact cluster of neurons.
- In anatomical sections, a nucleus shows up as a region of gray matter, often bordered by white matter.
- In addition, nucleus can refer to an identifiable distinct group of neurons that can spread over an extended area.
- For example, the reticular nucleus of the thalamus is a thin layer of inhibitory neurons that surround the thalamus.
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- In hydrogen-like atoms (those with only one electron), the net force on the electron is just as large as the electric attraction from the nucleus.
- However, when more electrons are involved, each electron (in the $n$-shell) feels not only the electromagnetic attraction from the positive nucleus, but also repulsion forces from other electrons in shells from '1' to '$n$'.
- Therefore, these electrons are not as strongly bonded to the nucleus as electrons closer to the nucleus.
- As an approximation, the effective nuclear charge on each electron can be estimated by: Zeff=Z−σZ_\text{eff} = Z - \sigma, where $Z$ is the number of protons in the nucleus and σ\sigma is the average number of electrons between the nucleus and the electron in question. σ\sigma can be found by using quantum chemistry and the Schrodinger equation or by using Slater's empirical formula.
- A multielectron atom with inner electrons shielding outside electrons from the positively charged nucleus
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- However, the nucleus can be modelled as a sphere of positive charge for the interpretation of electron scattering experiments: because there is no definite boundary to the nucleus, the electrons "see" a range of cross-sections, for which a mean can be taken.
- Rutherford was able to put an upper limit on the radius of the gold nucleus of 34 femtometers (fm).
- This gives a charge radius for the gold nucleus ($A=197$) of about 7.5 fm.
- The nuclear density for a typical nucleus can be approximately calculated from the size of the nucleus:
- Note that the image is not to scale; in reality the nucleus is vastly smaller than the electron shell.