Words Starting With "R"
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Rotavirus
A virus that causes gastroenteritis, an inflammation of the stomach and intestines. It is the most common cause of severe diarrhea in children worldwide and often leads to dehydration.
Rotaxane
A rotaxane is a type of molecular architecture in organic chemistry. It consists of a macrocycle ('ring') that encircles a dumbbell-shaped component (axis), which contains two terminal groups. The macrocycle is mechanically bound to the axis by two end groups (á stators) through a process called coordination bonding.<br><br>Rotaxanes can be viewed as a combination of a macrocycle and a dumbbell-shaped molecule linked together. The macroring encircles the axis in a specific orientation and is held together by weak chemical bonds (e.g. dipole-dipole forces, van der Waals forces), which can be too weak to separate the component, hence the term "mechanochemical" is not used for molecules that sustain such bonds between their constituent parts.<br><br>Rotaxanes can be considered as a type of molecule that consists of three parts described as a macrocycle and two ends in which two of its non-covalent closures of the dumbbell-shaped axis.
Rotaxanes
Rotaxanes are a type of mechanically interlocked molecular architecture. In a rotaxane, a linear molecule (the axle) is threaded through a molecular ring (the wheel), and the two components are mechanically bonded together through covalent bonds.<br><br>Imagine a mechanical embodiment of a sliding door: the axle is like the door's rod, and the wheel is like the door. However, unlike a sliding door, the axle cannot be removed from the wheel in the case of a rotaxane.<br><br>Rotaxanes have unique properties due to their mechanical bonding:<br><br>1. <strong>Stability</strong>: The mechanical bonding between the wheel and the axle provides additional stability to the molecule.<br>2. <strong>ﾍSelective binding</strong>: The wheel-axle interaction can be selective, allowing the molecular system to bind specifically to certain targets.<br>3. <strong>Switching behavior</strong>: Rotaxanes can exhibit switching behavior by moving the wheel along the axle in response to external stimuli, such as changes in temperature, pH, or the presence of specific molecules.<br><br>Rotaxanes have various applications in fields like:<br><br>1. <strong>Supramolecular chemistry</strong>: Studying the interplay between the wheel and axle components provides insights into molecular recognition, binding selectivity, and energy transfer.<br>2. <strong>Molecular machines</strong>: Rotaxanes can be designed to perform tasks such as switching, oscillating, or pumping, which can lead to innovative self-assembly and nanoscale device applications.<br>3. <strong>Biomimetics</strong>: Rotaxane-based systems can be used to model biological processes, such as protein function, folding, and interactions.<br>4. <strong>Materials science</strong>: Rotaxanes can be utilized in the development of shape-memory materials, switchable metamaterials, and self-healing composites.<br><br>Overall, the interlocked architecture of rotaxanes enables sophisticated control and manipulation of molecular interactions, leading to a wide range of interesting properties and applications.
Rotc
The Junior Reserve Officers' Training Corps (JROTC) is a leadership and citizenship program for high school students. It's a covers both civics and first aid, and focuses on teaching students skills such as leadership, teamwork, and community service.
Rote
A memorized verbal routine or set of actions performed without much thought or creativity, often in a mechanical or automatic way: the secretary's workdays were a series of routine tasks; her life on the farm was a routine of hard work and rest.
Rotella
Rotella is a brand of automotive oil, but the word can also refer to a European surname, specifically Italian and Greek.
Rotenone
Rotenone is a naturally occurring chemical insecticide derived from the roots of certain plants, such as the Derris tree. It is a non-selective insecticide that works by inhibiting the energy-producing process in cells, killing insects and other organisms by suffocation. Rotenone is used to control insect pests, particularly in agriculture and in aquariums. It is also used in some fisheries to remove insects and other unwanted organisms from the water.
Rothera
Rothera Island, also known as Rothera, is a small Antarctic island lying south of Adelaide Island, in the Errera Channel, which connects it to the Antarctic mainland in Graham Land, Antarctica.
Rothes
Rothschilds <br><br>The Rothschilds were a wealthy banking dynasty of Jewish origin, beginning with Mayer Amschel Rothschild, who is considered the founder of the dynasty.
Rothesians
People from the town of Rothbury in Northumberland, northeast England, or more likely, a dialect term of endearment for someone from Rothbury.
Rothschild
The term "Rothschild" can refer to the Rothschild family, a wealthy and influential European banking dynasty that originated in Frankfurt, Germany in the 18th century. The family rose to prominence during the 18th and 19th centuries, particularly through their banking firm N M Rothschild & Sons, which had a significant impact on the world's financial markets.<br><br>Today, the Rothschild family is known for its significant wealth, with estimated combined wealth of over $400 billion. They continue to maintain a significant influence in the worlds of finance, politics, and philanthropy.<br><br>The term can also be used more broadly to refer to the following:<br><br> A communal name or surname shared by family members and descendants.<br> A term used to describe the privileges, advantages, or social benefits associated with the wealthy and influential members of the family.<br> A figure of metaphorical reference, often ironic or satirical, used to represent the very embodiment of wealth, power, or capitalism.
Roti
Roti is a type of flatbread that is commonly eaten in many parts of the world, particularly in South Asia, the Middle East, and the Caribbean. It is made from flour, water, and sometimes yeast, and is cooked on a hot surface or in a dry frying pan.
Rotifer
A rotifer is a small, usually microscopic, multicellular, non-vascular animal that belongs to the phylum Rotifera. They are found in aquatic environments, such as ponds, lakes, and streams, and feed on small organisms like bacteria, algae, and protozoa. Rotifers play an important role in the ecosystem as both predators and prey, and are often used as indicators of water quality.
Rotifera
Rotifera refers to a phylum of small, usually microscopic or near-microscopic, invertebrate animals. They are a group of aquatic animals, such as water fleas or wheel animals, that are characterized by a distinctive wheel-like pattern of cilia (hair-like appendages) on their bodies. These animals are an essential part of aquatic ecosystems and play a crucial role in the food chain, serving as both predators and prey for various aquatic organisms.
Rotifers
Rotifers are a group of small, spinning, usually transparent or translucent invertebrate animals that are commonly found in freshwater environments such as ponds, lakes, and slow-moving streams. They are an important part of the aquatic food chain and are often used as indicators of water quality.<br><br>Rotifers have a distinctive crown-like arrangement of cilia, or hair-like structures, around their mouth, which they use to capture small particles of food from the water. They are also equipped with a flexible, disk-shaped body that is divided into two parts: the trophi (or pharynx) and the body proper.<br><br>Rotifers are typically 0.2-2 millimeters in length and are an essential food source for many aquatic animals, including fish, amphibians, and invertebrates. They are also an important food source for young fish and amphibians.<br><br>Rotifers are often divided into two main subgroups:<br><br> Monogononta: Found in freshwater environments, these rotifers are usually small, with a characteristic crown of cilia around their mouth.<br> Bdelloidea: Found in freshwater and brackish environments, these rotifers have a distinctive shell-like structure on their body.<br><br>Overall, rotifers play a crucial role in aquatic ecosystems and are an important part of the nutrient cycle.
Rotigotine
Rotigotine is a non-ergoline dopamine agonist with affinity for the dopamine D1, D2, D3, and D4 receptors, indicating it has a broad action on the dopamine system.<br><br>It is primarily used to treat Parkinson's disease and restless leg syndrome, a condition characterized by feelings of unease in the legs that can cause an irresistible urge to move them, often accompanied by uncomfortable sensations, such as tingling, burning, or itching.<br><br>As a dopamine agonist, rotigotine works by stimulating the brain's dopamine receptors, mimicking the action of dopamine, a neurotransmitter that plays a crucial role in movement control and coordination. In Parkinson's disease, the degeneration of dopamine-producing neurons leads to motor symptoms, such as tremors, stiffness, and bradykinesia (slow movement).<br><br>By increasing dopamine activity in the brain, rotigotine helps alleviate these symptoms and improve motor function.
Rotisserie
A device for cooking food, typically meat, by turning it slowly on a spit over heat, often used in a restaurant or commercial kitchen.
Roto-tiller
A roto-tiller, also known as a rotary tiller or a garden tiller, is a garden tool used to loosen and aerate soil. It consists of a rotating shaft with rotating blades that break up and turn over the soil, making it easier to till and prepare for planting.
Rotodyne
A rotodyne, or ducted fan, is a type of aircraft propulsion system that uses a fan to generate thrust, similar to a turboprop engine, but with a much larger, more ducted fan. It was developed in the 1950s and 1960s, and was intended as a more efficient alternative to traditional propellers or jet engines.<br><br>In a rotodyne, the fan is ducted, meaning it is surrounded by a casing, and it uses the principles of propeller propulsion but with a larger, slower-turning fan. This ducting is designed to reduce noise and increase efficiency, and to allow the fan to generate more thrust at a slower speed.<br><br>The rotodyne was also intended to reduce the amount of vibration and noise generated by propellers, by encapsulating the fan within a casing. The rotodyne was also designed to be more efficient than traditional propellers, by using the Bernoulli's principle to generate additional thrust by accelerating the air coming out of the duct.<br><br>The rotodyne is also referred to as a ducted fan, or a ducted propeller. It is a standout technology for personal aircraft like trainer planes, ambulances, or military surveillance planes.
Rotogravure
Rotogravure is a method of etching and printing that involves etching an image onto a smooth cylinder or roller, which is then used to print the image onto a medium, such as paper or fabric. It is a type of intaglio printing. The word "rotogravure" comes from the French words "rotor" meaning rotor, and "gravure" meaning etching.
Rotor
A rotor is a part of a machine, especially a motor or engine, that rotates around a central axis, conveying forces from a drive shaft to a load or transferring energy from a prime mover to a work surface.
Rotorcraft
A rotorcraft is a type of aircraft that uses rotor blades to generate lift, such as a helicopter or a gyrocopter.
Rotors
Rotors can refer to:<br><br> A part of an engine, particularly in a helicopter, aircraft, or a type of generator that converts mechanical energy into electrical energy.<br> A series of blades or vanes that rotate to change the direction of airflow in a fan or a blower.<br> A term used in cryptography to describe a processing unit in an electric solitary vending machine.<br> The act of rotating or to a device with rotating parts.
Rotorua
Rotorua is a city in the North Island of New Zealand, situated on the shores of Lake Rotorua. It is known for its natural geothermal wonders, such as hot springs, geysers, and mud pools, which are a result of its volcanic origin. The city is a popular tourist destination, attracting visitors from all over the world to experience its unique geothermal features and to learn about the area's rich Maori culture and history.<br><br>The name "Rotorua" is derived from the Maori language, with "Roto" meaning "lake" and "Rua" meaning "reddened" or "inflamed", referring to the bright red color of the lake's water.<br><br>Rotorua is also home to numerous adventure activities, such as bungee jumping, skydiving, and hiking, making it an ideal destination for thrill-seekers and outdoor enthusiasts.
Rotoscope
Rotoscope is a technique of tracing over live-action footage frame by frame to create the illusion of animation. It involves creating a cel with a stylized drawing or tracing over each frame of live-action footage to create a animated effect. This technique is often used to create stylized, hand-drawn, and grainy animated sequences that give a unique visual appearance.
Rotoscoped
Rotoscoping is a technique in animation and filmmaking where live-action footage is traced over to create the illusion of animation or a stylized, hand-drawn look.
Rotoscopes
A type of animation technique where an artist traces over live-action footage, frame by frame, to create a cartoon-like effect. The resulting animation can be used to add special effects, create interesting visuals, or transform one object or character into another.
Rotoscoping
Rotoscoping is a technique used in animation or filmmaking where live-action footage is traced over frame by frame with a painterly or hand-drawn element. This process involves obtaining live action footage and then drawing or painting over each frame to create a look that blends live-action performance with animation.<br><br>The result is a dreamlike, stylized animation with a unique visual identity that can be used to create distinctive visual effects, evoke a specific mood or atmosphere, or add a touch of hand-crafted charm to a film or video. Rotoscoping allows filmmakers to create a range of effects, from subtle texture overlays to complete animation transformations of the original footage.<br><br>Rotoscoping has been used in various iconic films and commercials, including Walt Disney's "Tron" and "A Trip to Tikitown," as well as in the animated film "Mostly Harmless" and the music video for Beck's "Cellphone's Dead." By turning live-action footage into animated scenes, rotoscoping gives creators a tool to re-imagine and re-design the visual elements of an scene in a creative and unique way.
Rototiller
A rototiller is a farming tool used to break up and aerate the soil. It typically has a rotating shaft with tines or blades that cut through the soil, loosening and turning it over. This is often done to prepare the soil for planting, or to remove weeds and debris.
Rotproof
Resistance to decay or decomposition, especially because of some antiseptic or preservative.
Rots
To rot: to decay or spoil, often because of a lack of fresh air or water, or because of bacterial or fungal infection.<br><br>Example: The fruit has started to rot because it was left on the counter too long.<br><br>To rot (someone's) nerves: to annoy or frustrate someone to the point of causing anxiety or psychological distress.<br><br>Example: The constant noise was rotting her nerves.<br><br>Rot: decay or deterioration, often of a physical substance.<br><br>Example: The rot in the wood caused it to collapse.