Inversion recovery is a technique used in magnetic resonance imaging (MRI) to enhance the contrast of images by manipulating the relaxation properties of tissues. The fundamental principle behind inversion recovery involves applying an inversion pulse to the spins of hydrogen nuclei (protons) in the body. Here’s how it works: 1. **Inversion Pulse**: The sequence starts with a 180-degree radiofrequency (RF) pulse that inverts the magnetization of the tissue.
Magic Angle Spinning (MAS) is a technique used in the field of nuclear magnetic resonance (NMR) spectroscopy, particularly for solid-state NMR. It is employed to enhance the resolution of NMR spectra of solid samples, which typically suffer from broad lines due to dipolar couplings and chemical shift anisotropy. The key concept behind MAS is to rotate the sample at a specific angle (the "magic angle," approximately 54.
Magnetization transfer is a phenomenon observed in magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) spectroscopy. It involves the transfer of magnetization from one pool of protons (nuclei) to another, typically between freely moving (mobile) protons and those that are closely bound within macromolecules or in less mobile environments. In MRI, magnetization transfer is utilized to enhance contrast between different tissues.
In the context of magnetism, a shim refers to a material or device used to correct or adjust the magnetic field of a magnet. Shimming is an important process in various applications, especially in magnetic resonance imaging (MRI) and particle accelerators, where uniform and precise magnetic fields are critical for performance.
TRISPHAT (or TRISPAT) is a synthetic compound that has been explored for various applications, notably in scientific research, particularly in biochemistry and molecular biology. It typically refers to a specific type of phosphonate or phosphorothioate compound used in the synthesis of oligonucleotides and nucleic acid analogs.
A "trigger zone" can refer to different concepts depending on the context in which it's used. Here are a few interpretations: 1. **Psychology/Therapy**: In mental health, a trigger zone can refer to a specific situation, location, or stimuli that evokes a strong emotional reaction, often related to past trauma or anxiety. Identifying trigger zones is an important part of therapy, as it helps individuals understand their reactions and develop coping strategies.
The basal electrical rhythm (BER), also known as slow wave activity, refers to the rhythmic electrical activity produced by pacemaker cells in certain tissues of the body, primarily in the gastrointestinal (GI) tract. These electrical waves facilitate the coordinated contractions of smooth muscle, which are essential for digestive movements. 1. **Location**: In the GI tract, the BER is primarily generated by specialized cells called interstitial cells of Cajal (ICC), which are located between the layers of the smooth muscle.
A bioamplifier is an electronic device or system designed to amplify biological signals, which can include electrical signals generated by biological systems such as muscles, nerves, or cells. These signals are typically very weak and need to be amplified to be useful for analysis, monitoring, or control applications. Bioamplifiers are commonly used in various fields, including medical diagnostics, biological research, and biomedical engineering.
Biothesiometry is a clinical assessment technique used to measure tactile sensitivity and vibratory perception in the skin. It utilizes a specialized device called a biothesiometer, which delivers vibrations at varying frequencies and intensities to different areas of the skin, usually on the feet or hands. The primary purpose of biothesiometry is to evaluate sensory nerve function and detect neuropathies, particularly in conditions such as diabetes, where peripheral neuropathy is common.
Clinical electrophysiology is a specialized branch of medicine that focuses on the study and treatment of electrical activities in the heart and nervous system. It plays a crucial role in diagnosing and managing various cardiac and neurological conditions related to abnormal electrical signals. ### Key Areas of Clinical Electrophysiology: 1. **Cardiac Electrophysiology**: - Involves the study of the heart's electrical system and its pathways.
Electrochemical skin conductance (ESC) is a biomarker used to measure the electrical properties of the skin, specifically its conductance. It reflects the activity of sweat glands and can provide information about an individual's physiological and emotional state. The measurement is typically obtained using electrodes placed on the skin, which detect changes in the electrical conductance resulting from the presence of sweat. ESC is often linked to the body's autonomic nervous system responses, particularly in relation to stress, arousal, and emotional states.
Electromyography (EMG) is a diagnostic procedure that assesses the electrical activity of muscles. It involves the use of electrodes—either surface electrodes placed on the skin or needle electrodes inserted into the muscle—to detect the electrical signals produced by muscle fibers during contraction.
Electrooculography (EOG) is a technique used to measure the electrical potential difference between the front and back of the human eye. This electrical potential is generated by the movement of the eye muscles and the orientation of the retina. EOG is commonly utilized to track eye movements and assess various conditions related to visual and ocular health.
Electrotonic potential refers to the local changes in membrane potential that occur in a neuron or muscle fiber as a result of synaptic activity or the propagation of an electrical signal. It is often associated with the concept of passive electrical properties of cells, particularly in the context of signal transmission along neurons.
Graded potentials are small changes in the membrane potential of a neuron or other excitable cell that occur in response to stimuli. Unlike action potentials, which are all-or-nothing responses, graded potentials can vary in magnitude and direction depending on the strength and duration of the stimulus. Key characteristics of graded potentials include: 1. **Magnitude**: The amplitude of a graded potential is proportional to the strength of the stimulus. A stronger stimulus produces a larger graded potential.
Local field potentials (LFPs) are electrical signals recorded from a specific region of the brain or a similar biological tissue. They represent the summed electrical activity of multiple nearby neurons and are primarily associated with the activity of synaptic potentials, rather than the action potentials of individual neurons. LFPs are measured using microelectrodes that are typically inserted into the tissue.
A Mercury swivel commutator is a type of electrical component used primarily in certain types of electric motors and generators, particularly in applications where low wear and maintenance are desired. The commutator is designed to facilitate the transfer of electrical current between stationary and rotating parts of the machine. In a traditional commutator, segments of conductive material are used to switch the direction of current in the armature windings as they rotate, allowing for continuous motion in one direction.
Microneurography is a technique used to study the function of peripheral nerves by recording electrical activity from individual nerve fibers. It involves inserting a very fine microelectrode into a peripheral nerve, typically in the leg or arm, to measure the action potentials (nerve impulses) generated by specific nerve fibers. This technique allows researchers and clinicians to gain insights into the sensory and motor functions of nerve fibers, the mechanisms of pain, and the effects of various diseases on nerve function.
Plateau potentials are a type of sustained depolarization that occurs in certain types of neurons and muscle cells. They are characterized by a prolonged period of depolarization, which makes the cell membrane more positive and can lead to an extended period of action potential firing or muscle contraction. In neurons, plateau potentials are often associated with specific types of excitability and are involved in functions such as rhythm generation in certain circuits (e.g., in neurons of the cardiac pacemaker or certain motor neurons).
Receptor potential refers to the graded electrical change that occurs in sensory receptor cells when they are activated by an appropriate stimulus. This change is part of the process of sensory transduction, where an external stimulus (like light, sound, or pressure) is converted into an electrical signal that can be interpreted by the nervous system. When a sensory receptor is stimulated, it typically causes the opening or closing of ion channels in the cell membrane, leading to a change in the membrane potential.
Pinned article: ourbigbook/introduction-to-the-ourbigbook-project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.Figure 3. Visual Studio Code extension installation.Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. - Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact