The term "stretch factor" can refer to different concepts depending on the context in which it is used. Here are a few interpretations of "stretch factor": 1. **Mathematics and Geometry**: In the context of geometric transformations, the stretch factor refers to the ratio by which a shape is stretched or scaled. For example, if a line segment is stretched to twice its original length, the stretch factor is 2.

A **sub-Riemannian manifold** is a differentiable manifold equipped with a certain kind of generalized metric structure that allows for the measurement of lengths and distances along curves, but only in a constrained manner.

Nucleic acid secondary structure refers to the specific three-dimensional shapes that nucleic acids (DNA and RNA) can form as a result of hydrogen bonding between the nucleotides. This structure is crucial for the functionality of nucleic acids, influencing processes such as replication, transcription, and translation.

Nicolae Vasilescu-Karpen (1881–1964) was a Romanian engineer and inventor, best known for his work in the field of electrical engineering and for significant contributions to thermoelectricity and energy conversion. He is particularly noted for developing the "Karpen battery," a type of thermoelectric generator that operates based on the principles of thermoelectricity.

"Polish women physicists" refers to female physicists from Poland who have made significant contributions to the field of physics. While historically, the sciences, including physics, have been male-dominated, many Polish women have excelled and made impactful contributions in various areas of physics, such as theoretical physics, experimental physics, and applied physics.

"Romanian astrophysicists" refers to astrophysicists from Romania or those who conduct their research and work in Romania, contributing to the study of the universe, celestial bodies, and the fundamental laws of physics governing them. Romania has a number of institutions and universities engaged in astronomical and astrophysical research, including the Astronomical Institute of the Romanian Academy and the University of Bucharest.

Ion I. Agârbiceanu (1882–1963) was a Romanian writer, journalist, and politician, known for his contributions to Romanian literature and his involvement in the cultural and social life of Romania. He is particularly recognized for his novels, short stories, and essays that often depict the rural life and traditions of Transylvania. His works reflect themes of social justice, morality, and the struggles of the peasant class.

Ștefan C. Hepites is not widely recognized as a notable figure in popular media, history, or other well-documented fields as of my last update in October 2021. It's possible that he may be a lesser-known individual, or perhaps a local figure, artist, or academic whose prominence has emerged more recently or is not well-documented in widely accessible sources.

Russian biophysicists are scientists from Russia who specialize in the field of biophysics, which is an interdisciplinary area combining principles and methods from physics with biological systems. Biophysicists study the physical principles underlying biological processes, including the structure and function of biomolecules, cellular mechanisms, and physiological phenomena. In Russia, biophysics has a rich history, with contributions from renowned scientists and institutions.

Dmitry Kolker was a Russian scientist and professor known for his work in the field of quantum optics and laser physics. He gained some public attention for his contributions to research and education in these areas. Unfortunately, as of my last knowledge update in October 2021, I do not have any further specific details beyond that. Please check current sources for the most up-to-date information about his work or any recent developments related to him.

As of my last knowledge update in October 2021, there isn't a widely recognized individual named Andrei Tverdokhlebov. It's possible that he may not be a public figure, or information about him hasn't reached widespread visibility in news or popular culture. If he has gained prominence after my last training cut-off, I would not have that information. Please provide additional context or check current sources for the most up-to-date information.

Irina Novikova is a physicist known for her work in the field of quantum optics and photonics. She has made significant contributions to areas such as electromagnetically induced transparency (EIT), quantum memory, and the interaction of light with matter. Her research often involves exploring how light can be controlled and manipulated at the quantum level, which has important implications for quantum information science and technology.

Lev Pitaevskii is a notable Russian physicist known for his significant contributions to the fields of statistical mechanics and condensed matter physics. He is particularly recognized for his work on quantum fluids, including Bose-Einstein condensates, and for co-developing the Gross-Pitaevskii equation, which describes the behavior of such systems.

Michael Tendler is not a widely recognized public figure, so there is limited information available about a person by that name. It's possible that he is a private individual or someone who may have emerged in news or popular culture after my last update in October 2023.

Nikolay Sukhomlin is a name that may refer to various individuals, but it is not widely recognized in prominent historical, scientific, or cultural contexts as of my last training data up to October 2023.

Sergey Bagayev is a scientist known for his work in the fields of mathematics and computer science. While specific details about his contributions may vary, he is typically recognized for his research and publications in areas such as algorithms, computational theory, and potentially other interdisciplinary applications involving mathematics and technology.

Yaroslav Blanter is a physicist known for his work in statistical mechanics, condensed matter physics, and quantum information theory. He has made significant contributions to our understanding of various phenomena in these fields.

Scottish women physicists are women from Scotland who have made significant contributions to the field of physics. Throughout history, women in science, including physics, have often faced various challenges and barriers, but many have achieved notable accomplishments and have played crucial roles in advancing our understanding of the physical world.

Alfred Ewing could refer to Alfred Ewing, a notable figure in the field of philosophy and science. He is best known for his contributions to the philosophy of mind, philosophy of science, and the philosophy of language. Ewing was also involved in discussions related to ethics and the philosophy of religion.

Soudan 2 is a neutrino detector located at the Soudan Underground Laboratory in Minnesota, USA. It was originally constructed as a continuation of the work in the field of particle physics aimed at detecting neutrinos, which are extremely light and elusive subatomic particles. Soudan 2 began full operations in the late 1980s and was designed to study neutrinos produced by cosmic rays and by the Sun.