Computers Math

The sex hormone commonly known as estrogen plays an important role in multiple aspects of women’s health and fertility. High levels of estrogen in the body are associated with breast and ovarian cancers, while low levels of estradiol can result in osteoporosis, heart disease, and even depression. (Estrogen is a class of hormones that includes estradiol as the most potent form). Estradiol is also necessary for the development of secondary sexual characteristics in women and regulates the reproductive cycle.
Because of its many functions, the hormone estradiol is often specifically monitored by physicians as part of women’s health care, but this usually requires the patient to visit a clinic to have blood drawn for analysis in a lab. Even at-home testing kits require samples of blood or urine to be mailed to a lab.
But now Caltech researchers have developed a wearable sensor that monitors estradiol by detecting its presence in sweat. The researchers say the sensor may one day make it easier for women to monitor their estradiol levels at home and in real time.
The research was conducted in the lab of Wei Gao, assistant professor of medical engineering, investigator with the Heritage Medical Research Institute, and Ronald and JoAnne Willens Scholar. In recent years, Gao has developed sweat sensors that detect cortisol, a hormone associated with stress; the presence of the COVID-19 virus; a biomarker indicating inflammation in the body; and a whole slew of other nutrients and biological compounds.
Gao says the development of the estradiol sensor was spurred in part by requests from people who were unsatisfied with the options they had for monitoring their estrogen levels and had seen his previous work.
“People often ask me if I could make the same kind of sweat sensor for female hormones, because we know how much those hormones impact women’s health,” Gao says.
One population of women who would benefit from estradiol monitoring are those who are attempting to conceive a child, either naturally or through in vitro fertilization. The success of either method is dependent on getting timing right with regards to ovulation, but not all women have a reproductive cycle that follows a regular schedule. Some women have been able to track their ovulation by monitoring their body temperature, but Gao says that method has limited usefulness because it’s not very accurate and body temperature doesn’t increase until ovulation has begun. More

Patterns of chemical interactions are thought to create patterns in nature such as stripes and spots. This new study shows that the mathematical basis of these patterns also governs how sperm tail moves.
The findings, published today in Nature Communications, reveal that flagella movement of, for example, sperm tails and cilia, follow the same template for pattern formation that was discovered by the famous mathematician Alan Turing.
Flagellar undulations make stripe patterns in space-time, generating waves that travel along the tail to drive the sperm and microbes forward.
Alan Turing is most well-known for helping to break the enigma code during WWII. However he also developed a theory of pattern formation that predicted that chemical patterns may appear spontaneously with only two ingredients: chemicals spreading out (diffusing) and reacting together. Turing first proposed the so-called reaction-diffusion theory for pattern formation.
Turing helped to pave the way for a whole new type of enquiry using reaction-diffusion mathematics to understand natural patterns. Today, these chemical patterns first envisioned by Turing are called Turing patterns. Although not yet proven by experimental evidence, these patterns are thought to govern many patterns across nature, such as leopard spots, the whorl of seeds in the head of a sunflower, and patterns of sand on the beach. Turing’s theory can be applied to various fields, from biology and robotics to astrophysics.
Mathematician Dr Hermes Gadêlha, head of the Polymaths Lab, and his PhD student James Cass conducted this research in the School of Engineering Mathematics and Technology at the University of Bristol. Gadêlha explained: “Live spontaneous motion of flagella and cilia is observed everywhere in nature, but little is known about how they are orchestrated.
“They are critical in health and disease, reproduction, evolution, and survivorship of almost every aquatic microorganism in earth.”
The team was inspired by recent observations in low viscosity fluids that the surrounding environment plays a minor role on the flagellum. They used mathematical modelling, simulations, and data fitting to show that flagellar undulations can arise spontaneously without the influence of their fluid environment. More

A groundbreaking development in biomedical engineering has led to the creation of a human stomach micro-physiological system (hsMPS), representing a significant leap forward in understanding and treating various gastrointestinal diseases, including stomach cancer. The research team, led by Professor Tae-Eun Park from the Department of Biomedical Engineering at UNIST and Professor Seong-Ho Kong from Seoul National University Hospital, has successfully developed a biomimetic chip that combines organoid and organ-on-a-chip technologies to simulate the complex defense mechanisms of the human gastric mucosa.
Organoids, which mimic human organs using stem cells, have shown great potential as in vitro models for studying specific functions. However, they lack the ability to replicate mechanical stimulation or cell-to-cell interactions found within the human body. This limitation prompted researchers to develop an innovative biochip capable of recreating real-life gastric mucosal protection systems.
The newly developed biochip incorporates fluid flow within its microfluidic channels to simulate mechanical stimuli and facilitate cell-to-cell interactions. Mesenchymal substrate cells exposed to fluid flow activate gastric stem cell proliferation while promoting cellular differentiation balance. This process ultimately mimics key features necessary for developing functional gastric mucosal barriers at a biologically relevant level.
One remarkable achievement demonstrated by this hsMPS is its ability to uncover previously unseen defense mechanisms against Helicobacter pylori — a pathogen associated with various stomach diseases — in ways that were not possible with existing models. Gastric mucosal peptide known as TFF1 was observed forming mosaic-like structures within groups infected with Helicobacter pylori — forming a protective barrier essential for establishing an efficient defense system against external infectious factors. Suppression of gastric mucosal peptide expression resulted in more severe inflammatory reactions.
“This study presents our model’s potential for observing dynamic interactions between epithelial cells and immune cells in chips infected with Helicobacter pylori, contributing to a comprehensive understanding of gastric mucosal barrier stability,” explained Professor Park.
The research findings, supported by the Basic Research Laboratory (BRL) research grant from the National Research (NRF), funded by the Ministry of Science and ICT (MSIT), have been published online on July 31 in Advanced Science.
These groundbreaking advancements in hsMPS open up new avenues for studying host-microbe interactions, developing therapeutic strategies for gastric infections, and gaining a deeper understanding of gastrointestinal diseases. This innovative biochip technology has the potential to reduce reliance on animal experimentation while providing valuable insights into complex physiological processes within the human stomach. More

Quantum mechanics is a branch of physics that explores the properties and interactions of iparticles at very small scale, such as atoms and molecules. This has led to the development of new technologies that are more powerful and efficient compared to their conventional counterparts, causing breakthroughs in areas such as computing, communication, and energy.
At the Okinawa Institute of Science and Technology (OIST), researchers at the Quantum Systems Unit have collaborated with scientists from the University of Kaiserslautern-Landau and the University of Stuttgart to design and build an engine that is based on the special rules that particles obey at very small scales.
They have developed an engine that uses the principles of quantum mechanics to create power, instead of the usual way of burning fuel. The paper describing these results is co-authored by OIST researchers Keerthy Menon, Dr. Eloisa Cuestas, Dr. Thomas Fogarty and Prof. Thomas Busch and has been published in the journal Nature.
In a classical car engine, usually a mixture of fuel and air is ignited inside a chamber. The resulting explosion heats the gas in the chamber, which in turn pushes a piston in and out, producing work that turns the wheels of the car.
In their quantum engine the scientists have replaced the use of heat with a change in the quantum nature of the particles in the gas. To understand how this change can power the engine, we need to know that all particles in nature can be classified as either bosons or fermions, based on their special quantum characteristics.
At very low temperatures, where quantum effects become important, bosons have a lower energy state than fermions, and this energy difference can be used to power an engine. Instead of heating and cooling a gas cyclically like a classical engine does, the quantum engine works by changing bosons into fermions and back again.
“To turn fermions into bosons, you can take two fermions and combine them into a molecule. This new molecule is a boson. Breaking it up allows us to retrieve the fermions again. By doing this cyclically, we can power the engine without using heat,” Prof. Thomas Busch, leader of the Quantum Systems Unit explained. More

Is it possible to make a femtosecond laser entirely out of glass? That’s the rabbit hole that Yves Bellouard, head of EPFL’s Galatea Laboratory, went down after years of spending hours — and hours — aligning femtosecond lasers for lab experiments.
The Galatea laboratory is at the crossroads between optics, mechanics and materials science, and femtosecond lasers is a crucial element of Bellouard’s work. Femtosecond lasers produce extremely short and regular bursts of laser light and have many applications such as laser eye surgery, non-linear microscopy, spectroscopy, laser material processing and recently, sustainable data storage. Commercial femtosecond lasers are made by putting optical components and their mounts on a substrate, typically optical breadboards, which requires fastidious alignment of the optics.
“We use femtosecond lasers for our research on the non-linear properties of materials and how materials can be modified in their volume,” explains Bellouard. “Going through the exercise of painful complex optical alignments makes you dream of simpler and more reliable ways to align complex optics.”
Bellouard and his team’s solution? Use a commercial femtosecond laser to make a femtosecond laser out of glass, no bigger than the size of a credit card, and with less alignment hassles. The results are published in the journal Optica.
How to make a femtosecond laser out of glass
To make a femtosecond laser using a glass substrate, the scientists start with a sheet of glass. “We want to make stable lasers, so we use glass because it has a lower thermal expansion than conventional substrates, it is a stable material and transparent for the laser light we use,” Bellouard explains.
Using a commercial femtosecond laser, the scientists etch out special grooves in the glass that allow for the precise placement of the essential components of their laser. Even at micron level precision fabrication, the grooves and the components are not sufficiently precise by themselves to reach laser quality alignment. In other words, the mirrors are not yet perfectly aligned, so at this stage, their glass device is not yet functional as a laser. More

Movement offers a window into how the brain operates and controls the body. From clipboard-and-pen observation to modern artificial intelligence-based techniques, tracking human and animal movement has come a long way. Current cutting-edge methods utilize artificial intelligence to automatically track parts of the body as they move. However, training these models is still time-intensive and limited by the need for researchers to manually mark each body part hundreds to thousands of times.
Now, Associate Professor Eiman Azim and team have created GlowTrack, a non-invasive movement tracking method that uses fluorescent dye markers to train artificial intelligence. GlowTrack is robust, time-efficient, and high definition — capable of tracking a single digit on a mouse’s paw or hundreds of landmarks on a human hand.
The technique, published in Nature Communications on September 26, 2023, has applications spanning from biology to robotics to medicine and beyond.
“Over the last several years, there has been a revolution in tracking behavior as powerful artificial intelligence tools have been brought into the laboratory,” says Azim, senior author and holder of the William Scandling Developmental Chair. “Our approach makes these tools more versatile, improving the ways we capture diverse movements in the laboratory. Better quantification of movement gives us better insight into how the brain controls behavior and could aid in the study of movement disorders like amyotrophic lateral sclerosis (ALS) and Parkinson’s disease.”
Current methods to capture animal movement often require researchers to manually and repeatedly mark body parts on a computer screen — a time-consuming process subject to human error and time constraints. Human annotation means that these methods can usually only be used in a narrow testing environment, since artificial intelligence models specialize to the limited amount of training data they receive. For example, if the light, orientation of the animal’s body, camera angle, or any number of other factors were to change, the model would no longer recognize the tracked body part.
To address these limitations, the researchers used fluorescent dye to label parts of the animal or human body. With these “invisible” fluorescent dye markers, an enormous amount of visually diverse data can be created quickly and fed into the artificial intelligence models without the need for human annotation. Once fed this robust data, these models can be used to track movements across a much more diverse set of environments and at a resolution that would be far more difficult to achieve with manual human labeling.
This opens the door for easier comparison of movement data between studies, as different laboratories can use the same models to track body movement across a variety of situations. According to Azim, comparison and reproducibility of experiments are essentialin the process of scientific discovery. More

One-hour training is enough for people to carry a task alone with their supernumerary robotic arms as effectively as with a partner, study finds.
A new study by researchers at Queen Mary University of London, Imperial College London and The University of Melbourne has found that people can learn to use supernumerary robotic arms as effectively as working with a partner in just one hour of training.
The study, published in the journal IEEE Open Journal of Engineering in Medicine and Biology, investigated the potential of supernumerary robotic arms to help people perform tasks that require more than two hands. The idea of human augmentation with additional artificial limbs has long been in science fiction, like in Doctor Octopus in The Amazing Spider-Man (1963).
“Many tasks in daily life, such as opening a door while carrying a big package, require more than two hands,” said Dr Ekaterina Ivanova, lead author of the study from Queen Mary University of London. “Supernumerary robotic arms have been proposed as a way to allow people to do these tasks more easily, but until now, it was not clear how easy they would be to use.”
The study involved 24 participants who were asked to perform a variety of tasks with a supernumerary robotic arm. The participants were either given one hour of training in how to use the arm, or they were asked to work with a partner.
The results showed that the participants who had received training on the supernumerary arm performed the tasks just as well as the participants who were working with a partner. This suggests that supernumerary robotic arms can be a viable alternative to working with a partner, and that they can be learned to use effectively in a relatively short amount of time.
“Our findings are promising for the development of supernumerary robotic arms,” said Dr Ivanova. “They suggest that these arms could be used to help people with a variety of tasks, such as surgery, industrial work, or rehabilitation.”
The study was funded by the EU H2020 NIMA (FETOPEN 899626), TRIMANUAL (MSCA 843408) and CONBOTS (ICT 871803) grants. More

In the future, quantum computers may be able to solve problems that are far too complex for today’s most powerful supercomputers. To realize this promise, quantum versions of error correction codes must be able to account for computational errors faster than they occur.
However, today’s quantum computers are not yet robust enough to realize such error correction at commercially relevant scales.
On the way to overcoming this roadblock, MIT researchers demonstrated a novel superconducting qubit architecture that can perform operations between qubits — the building blocks of a quantum computer — with much greater accuracy than scientists have previously been able to achieve.
They utilize a relatively new type of superconducting qubit, known as fluxonium, which can have a lifespan that is much longer than more commonly used superconducting qubits.
Their architecture involves a special coupling element between two fluxonium qubits that enables them to perform logical operations, known as gates, in a highly accurate manner. It suppresses a type of unwanted background interaction that can introduce errors into quantum operations.
This approach enabled two-qubit gates that exceeded 99.9 percent accuracy and single-qubit gates with 99.99 percent accuracy. In addition, the researchers implemented this architecture on a chip using an extensible fabrication process.
“Building a large-scale quantum computer starts with robust qubits and gates. We showed a highly promising two-qubit system and laid out its many advantages for scaling. Our next step is to increase the number of qubits,” says Leon Ding PhD ’23, who was a physics graduate student in the Engineering Quantum Systems (EQuS) group and is the lead author of a paper on this architecture. More