It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Tuesday, July 09, 2024
New technique offers unprecedented control over light at terahertz frequencies
LIGHT PUBLISHING CENTER, CHANGCHUN INSTITUTE OF OPTICS, FINE MECHANICS AND PHYSICS, CAS
IMAGE:
(A) SCHEMATIC DIAGRAM OF THE EXPERIMENTAL SETUP. (B) SCHEMATICS OF THE LASER-ASSISTED-MAGNETIC-PROGRAMMING METHOD.
CREDIT: BY SHUNJIA WANG, WENTAO QIN, TONGYANG GUAN, JINGYU LIU, QINGNAN CAI, SHENG ZHANG, LEI ZHOU, YAN ZHANG, YIZHENG WU, ZHENSHENG TAO
Researchers have developed a novel method for generating structured terahertz light beams using programmable spintronic emitters. This breakthrough offers a significant leap forward in terahertz technology, enabling the generation and manipulation of light with both spin and orbital angular momentum at these frequencies for the first time.
Terahertz radiation lies between microwaves and infrared light on the electromagnetic spectrum. It holds great promise for various applications, including security scanners, medical imaging, and ultrafast communication. However, generating and controlling terahertz light effectively has proven challenging.
This new research, led by Prof. Zhensheng Tao, Prof. Yizheng Wu from Fudan University and Prof. Yan Zhang from Capital Normal University, overcomes these limitations by employing programmable spintronic emitters based on exchange-biased magnetic multilayers. These devices consist of thin layers of magnetic and non-magnetic materials that convert laser-induced spin-polarized currents into broadband terahertz radiation.
"The key innovation lies in our ability to flexibly program the magnetization pattern within the emitter with high precision and high spatial resolution," graduate student and first author Shunjia Wang explains. "This allows us to design and generate terahertz beams with complex polarization states, including beams with spatially separated circular polarizations, azimuthal or radial polarization states, and even a full Poincaré beam."
A Poincaré beam exhibits all possible states of light polarization within its cross-section. This unique property has applications in areas like generating special optical forces, achieving flat-top intensity profiles, and single-shot polarimetry measurements.
The researchers successfully demonstrated the generation of various structured terahertz beams using their programmable emitters. These beams hold promise for advancing terahertz technologies in numerous fields.
"Our findings pave the way for the development of novel terahertz devices with enhanced functionalities," concludes Prof. Zhensheng Tao. "The ability to manipulate terahertz light with such precision opens exciting possibilities for applications in spectroscopy, sensing, and communication."
(a) Programmed terahertz emitter for spatially separated left- and right-circularly polarized terahertz radiation. (b) Programmed terahertz emitter for azimuthal polarization. (c) Programmed terahertz emitter for the full Poincaré beam.
CREDIT
by Shunjia Wang, Wentao Qin, Tongyang Guan, Jingyu Liu, Qingnan Cai, Sheng Zhang, Lei Zhou, Yan Zhang, Yizheng Wu, Zhensheng Tao
UAB researchers were involved in the development of a switch, an essential device in telecommunications, capable of operating at very high frequency with lower power consumption than conventional technologies. The technology has applications in the new 6G mass communication systems and is more sustainable in terms of energy consumption than current devices. The study was published recently in Nature Electronics.
An indispensable element for controlling signals in electronic communication devices is the switch, whose function is to allow an electrical signal to pass (ON state) or to block it (OFF state). The fastest elements currently used to perform this function are silicon-based (the so-called RF silicon-on-insulator MOSFET switches) and operate using signals with frequencies of tens of gigahertz (GHz). However, they are volatile, i.e., they require a constant power source to maintain the ON state. To improve current communication systems and meet the demand for increasingly faster communications that will involve the Internet of Things (IoT) and the popularisation of virtual reality, it is necessary to increase the frequency of the signals with which these elements are able to act, and improve their performance.
An international collaboration involving researchers from the UAB Department of Telecommunications and Systems Engineering has developed a switch that, for the first time, is capable of performing at twice the operating frequency of current silicon-based devices, with a frequency range of up to 120 GHz, and without the need to apply a constant voltage.
The new switch uses a non-volatile material, called hBN (Hexagonal Boron Nitride), which allows its ON or OFF state to be activated by applying an electrical voltage pulse instead of a constant signal. In this way, the energy savings that can be attained are very significant.
"Our research team from the Department of Telecommunications and Systems Engineering at the UAB was involved in the design of the devices and their experimental characterisation in the laboratory," explains researcher Jordi Verdú. "For the first time we have been able to demonstrate the operation of a switch based on hBN, a non-volatile material, in a frequency range of up to 120 GHz, which suggests the possibility of using this technology in the new 6G mass communications systems, where a very high number of these elements will be required". For Verdú, this is a "very important contribution, not only from the point of view of device performance, but also towards a much more sustainable technology in terms of energy consumption".
These devices work thanks to the property of memristance, the change in electrical resistance of a material when a voltage is applied. Until now, very fast switches had been developed experimentally from memristors (devices with memristance) created with two-dimensional networks of hexagonal boron nitride (hBN) bonded together to form a surface. With this arrangement, the device frequency could reach up to 480 GHz, but only for 30 cycles, i.e., with no practical application. The new proposal uses the same material, but arranged in a superposition of layers (between 12 and 18 layers in total) that can operate at 260 GHz and with a sufficiently high stability of about 2000 cycles to be implemented in electronic devices.
The research, recently published in the journal Nature Electronics, was coordinated by the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, with the involvement of researchers from the Department of Telecommunications and Systems Engineering at the UAB Jordi Verdú, Eloi Guerrero, Lluís Acosta and Pedro de Paco, as well as researchers from the University of Texas at Austin (USA), the Tyndall National Institute and University College Cork (both in Ireland).
THE RESEARCHERS USED CIRCUIT MODELING, ADVANCED MODULATION TECHNIQUES, AND POLARIZATION DIVERSITY TO DESIGN A MIMO TRANSCEIVER SYSTEM FOR BACKCOM APPLICATIONS, ACHIEVING A SPECTRAL EFFICIENCY OF 2.0 BPS/HZ AND IMPROVING ENERGY EFFICIENCY BY 40% COMPARED TO CONVENTIONAL TECHNIQUES.
CREDIT: PROFESSOR SANGKIL KIM FROM PUSAN NATIONAL UNIVERSITY
Backscatter communication (BackCom) is a promising low-power method for the widespread adoption of the Internet of Things (IoT) technologies, where connected devices reflect and modulate existing signals by altering their load impedance, rather than generating signals themselves. To achieve low bit error rates and high data rates, higher-order modulation schemes such as Quadrature Amplitude Modulation (QAM) are selected based on accurately modeled reflection coefficients. However, discrepancies between simulations and real-world measurements make it challenging to accurately predict the optimal reflection coefficient.
“As the technology for more efficient and reliable backscatter communication improves, it lowers the barrier for IoT adoption across numerous industries. This could lead to a proliferation of IoT devices and integrated sensing and communication (ISC), facilitating smart cities, more efficient industries, and enhanced personal and public services,” says Prof. Kim.
Transfer learning involves applying knowledge gained from one task to enhance performance on a related task. The researchers pretrained an artificial neural network (ANN) using simulated input bias voltages (VI and VQ). This initial training step familiarized the ANN with the load modulator behaviors across varying voltage conditions. The knowledge gained from the pretraining step was then used in a main training step, where the ANN was trained using experimental data to predict reflection coefficients based on VI and VQ inputs.
This transfer of knowledge enabled the ANN to improve its predictions, achieving a minimal deviation of only 0.81% between modeled and measured reflection coefficients. Using these accurate models, researchers selected optimal 4- and 16-QAM schemes by aligning predicted reflection coefficients with specific points in the QAM constellation. This optimization ensured energy-efficient data transmission, with total consumption below 0.6 mW, much lower than conventional wireless systems.
Following this, the researchers designed a 2 × 2 × 2 MIMO transceiver system for BackCom, featuring two transmit and two receive antennas with different polarizations (such as vertical and horizontal). This setup enhances signal reception, throughput, and efficiency in BackCom. Utilizing a dual-polarized Vivaldi antenna, the team achieved a high gain exceeding 11.5 dBi and effective cross-polarization suppression of 18 dB.
The researchers tested their algorithm and MIMO BackCom system in the 5.725 GHz to 5.875 GHz C-band of the Industrial, Scientific, and Medical band, offering a 150 MHz bandwidth. Their approach achieved a spectral efficiency of 2.0 bps/Hz using 4-QAM modulation, demonstrating effective bandwidth utilization. They also attained an error vector magnitude of 9.35%, indicating high reliability and efficiency in data transmission.
“The combination of accurate circuit modeling, advanced modulation techniques, and polarization diversity, all tested in over-the-air environments, presents a holistic approach to tackling the challenges in ISC and IoT,” says Prof. Kim.
Overall, the proposed system lays the groundwork for a highly reliable and efficient backscatter system for multiple applications, including consumer electronics, healthcare monitoring, smart infrastructure for urban management, environmental sensing, and even radar communication.
About the institute Pusan National University, located in Busan, South Korea, was founded in 1946, and is now the no. 1 national university of South Korea in research and educational competency. The multi-campus university also has other smaller campuses in Yangsan, Miryang, and Ami. The university prides itself on the principles of truth, freedom, and service, and has approximately 30,000 students, 1200 professors, and 750 faculty members. The university is composed of 14 colleges (schools) and one independent division, with 103 departments in all.
About the author Prof. Sangkil Kim graduated magna cum laude with a B.S. from Yonsei University in 2010. He earned his M.S. and Ph.D. from the Georgia Institute of Technology in 2012 and 2014, respectively. From 2015 to 2018, he was the lead engineer at Qualcomm, pioneering the world’s first 5G mmWave AiP module for mobile devices. In 2018, he joined Pusan National University, where his SWARM lab focuses on advanced mmWave phased antenna arrays, machine learning-enhanced backscattering communication, and RF-photonics systems. Dr. Kim has received several accolades, including the IET Premium Award in 2015 and the KIEES Young Researcher Award in 2019. He is also a member of the IEEE MTT-26 RFID, Wireless Sensors, and IoT Committee.
New research highlights the challenge of balancing the risks of overdiagnosing and underdiagnosing prostate cancer early enough to intervene and minimize risk of death. Recently, some experts have called for the lowest grade of prostate cancer—biopsy Gleason Grade Group (GGG) 1—to be reclassified as ‘benign.’ But a new study led by a researcher from Mass General Brigham has found that many patients with a biopsy GGG1 may have a more aggressive cancer than their biopsy alone suggests.
By looking at data from more than 10,000 patients at a university in Germany, researchers found that at least 8 percent of patients with this classification had a more aggressive form of prostate cancer. They also found that many of the patients with GGG1 who are at highest risk can be identified based on high PSA levels or 50 percent or more of their biopsy samples coming back positive. Maintaining a “cancer” classification for these higher risk patients could improve their treatment plan and minimize risk of death. Results are published in European Urology Oncology.
“Our study identifies two risk factors that help determine which patients with GGG1 are at heightened risk of aggressive disease and death,” said senior author Anthony D’Amico, MD, PhD, of the Department of Radiation Oncology at Brigham and Women’s Hospital, a founding member of the Mass General Brigham healthcare system. “For patients with GGG1 who are at heightened risk, we should continue to call their diagnosis cancer and we should report it back to their physician so that they can act on this information. For patients with GGG1 who do not have either of these risk factors, the chance of dying is much lower. But for clinicians caring for patients at greatest risk, our message is clear: Call it cancer, and look harder.”
D'Amico collaborated with colleagues from University Hospital Hamburg Eppendorf to analyze data from 10,228 patients with GGG1 prostate cancer who underwent radical prostatectomy (surgical removal of the prostate) at the university hospital in Germany. Of these patients, 9,249 were diagnosed based on transrectal ultrasound (TRUS)-guided biopsies, and 980 were diagnosed using a more modern approach that combines TRUS with MRI to detect prostate cancer more accurately. The study began enrolling patients in February 1992 and continued following them through November 2023.
Of the 10,228 patients in the study cohort, adverse pathology—that is, a higher-grade Gleason Group Score or positive pelvic lymph nodes—at the time of radical prostatectomy was found in 955 of 9,248 patients diagnosed using TRUS (10.33 percent) and 77 of 980 patients diagnosed using the combined biopsy approach (7.86 percent). About 6 percent of patients with GGG1 had a PSA level of 20 ng/ml or more and about 12-14 percent of patients with GGG1 had more than half of their systematic biopsies return a positive result. Patients with either of these indicators had a significantly elevated risk of adverse pathology, increased risk for early PSA failure, and risk of death.
The authors note potential limitations to their study, including that the study population is from a single institution, PSA levels prior to diagnosis were not available, and most patients had samples collected and diagnosed before combined biopsy became widely adopted and diagnostic guidelines were updated in 2014. However, researchers found the same result for what predicts increased risk of adverse pathology and early recurrence (within 18 months) despite taking the prostate out in patients diagnosed with both approaches.
D’Amico notes that for patients with GGG1 who have one or both indicators of heightened risk, there are steps that clinicians can take, such as doing a follow-up biopsy sooner or recommending genomic testing, to assess if aggressive prostate cancer is present but missed on initial biopsy so as to intervene earlier to minimize risk of aggressive disease and death/
“Physicians and patients can have an informed discussion about whether observation, active surveillance or treatment is the right approach,” he said. “But if all patients with GGG1 are labeled ‘benign,’ it may preclude those conversations from happening.”
Authorship: D’Amico’s co-authors on the paper include Derya Tilki, Ming-Hui Chen, Hartwig Huland, and Markus Graefen.
Paper cited: Tilki D et al. “Mortality Risk in patients with Biopsy Gleason Grade Group 1 Prostate Cancer” European Urology Oncology DOI: 10.1016/j.euo.2024.06.009
###
About Mass General Brigham
Mass General Brigham is an integrated academic health care system, uniting great minds to solve the hardest problems in medicine for our communities and the world. Mass General Brigham connects a full continuum of care across a system of academic medical centers, community and specialty hospitals, a health insurance plan, physician networks, community health centers, home care, and long-term care services. Mass General Brigham is a nonprofit organization committed to patient care, research, teaching, and service to the community. In addition, Mass General Brigham is one of the nation’s leading biomedical research organizations with several Harvard Medical School teaching hospitals. For more information, please visit massgeneralbrigham.org.
Mortality Risk in patients with Biopsy Gleason Grade Group 1 Prostate Cancer
Scientists design method to lessen reliance on air conditioning
UNIVERSITY OF SHARJAH
Scientists say they have found a way to cool buildings that will reduce dependence on energy-hungry air conditioners. They do not claim their design would keep buildings cool with virtually no energy requirements but confirm that once their method is adopted it could lower indoor temperature by 0.7 degrees centigrade.
The study published in the Journal of Architectural Engineering focuses on natural ventilation techniques which the scientists apply to a prototype building in the United Arab Emirates (UAE), a country where life is not bearable without keeping vampire air conditioning appliances running 24 hours per day throughout the year.
“The prototype building was real, and several tests have been run on it,” says Vittorino Belpoliti, associate professor of green building design and energy technologies at Sharjah University.
The research compares predicted results, simulated with specific software, and real recordings of the building's performance. It assesses the extent of heat gain control and dissipation in the building to improve indoor temperature and lower energy consumption – a process called passive cooling.
The scientists write, “The study described here analyzed natural ventilation techniques, operated in a real building in the United Arab Emirates (UAE), to assist passive cooling. The assessment has been conducted by comparing digital simulation results and field measurements.
“Computational fluid dynamics (CFD) was used to retrospectively understand and quantify the monitored contribution of natural ventilation toward cooling the building.”
Belpoliti, who is also the study’s first author, adds, “The findings of the study contribute to assist early-stage design, with special regard to passive cooling via natural ventilation, to achieve more sustainable buildings.
“Natural ventilation strategies such as cross-ventilation, chimney effect, and wind catcher (Barjeel) prove efficient in reducing the building's indoor temperature (by 0.7°C throughout the day). Natural ventilation cannot replace air conditioning, in the UAE, but can contribute to lower its use during mild seasons.”
The Barjeel or Barjil is an appellation referring to the once common wind towers that used to cool buildings in the UAE and the entire oil-rich Gulf region before the advent of air-conditioning gadgets.
Barjeel is an ingenious method of catching the breeze that has kept houses cool for centuries. But given the uptick in temperatures and the scorching heat in the UAE, Belpoliti says there is so far no way to cool a building without turning on air conditioning.
Reinforced concrete, steel and large panes of glass are the construction materials of choice in the UAE and other oil-rich Gulf states. As such, the buildings provide no insulation against sweltering heat outside, and according to Belpoliti, they are built without having passive cooling in mind.
However, the scientists note in their research that structures allowing natural ventilation like Barjeel can be added to private residential buildings, but the process needs “cooperation of the occupant, to practically operate (open/close) the house openings.”
The study is part of a research and education program called Know-Howse whose target is to boost people’s awareness to help construct houses that are friendly to the environment.
The idea, as stated in Know-Howse website, is “to conceive a prototype house as a test-unit extracted from a broader housing development … [that] combines occupants’ comfort with environmental goals, such as reducing land-use and resource consumption.
“The educational program is directed to the new generations of society members, and targets particularly nationals, who are responsible for high energy and resources consumption.”
The Know-Howse comprises a multidisciplinary team of students and researchers from the University of Sharjah and Italy’s University of Ferrara and its research arm Architettura>Energia Research Centre the Research.
"The KNOW HOWse was not just an energy efficient project, it was a whole educational program: a house that trained the occupant to behave with more awareness to energy, water, and other finite resources," maintains Belpoliti.
Total electricity consumption in the UAE is among the highest in the world. It is estimated at 122.39 bn kWh per year, of which nearly 70 per cent is guzzled by air conditioning. Any reduction of indoor temperature via passive cooling is certain to have an impact on demand and carbon emissions.
The scientists are aware of the exorbitant demand for power. Passive cooling, they add, can only partially reduce consumption. "In the UAE, natural ventilation cannot replace air conditioning, but it can greatly contribute to limit its use toward the achievement of more sustainable buildings for hot climates,” says Belpoliti.
The study, says Belpoliti, has already garnered some interest in just a few months since publishing particularly from companies, both local and international, providing support and sponsorship for the Dubai-based Solar Decathlon Middle East 2018, a body run by the Dubai Electricity and Water Authority and the US Department of Energy.
JOURNAL
Journal of Architectural Engineering
METHOD OF RESEARCH
Experimental study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Assessment of Natural Ventilation Techniques by Means of Measurements and Retrospective CFD Simulation on a Test Building
UTSA joins new consortium dedicated to nuclear security and nonproliferation
This marks the second NNSA consortium that UTSA will participate in to advance nuclear science
UNIVERSITY OF TEXAS AT SAN ANTONIO
IMAGE:
MILTOS ALAMANIOTIS, GREENSTAR ENDOWED FELLOW IN ENERGY AND ASSOCIATE PROFESSOR OF ELECTRICAL AND COMPUTER ENGINEERING AT THE UNIVERSITY OF TEXAS AT SAN ANTONIO.
The University of Texas at San Antonio (UTSA) has joined one of two newly established university consortia committed to nuclear security and nonproliferation. The consortia were awarded $50 million in cooperative agreements by the Office of Defense Nuclear Nonproliferation in the U.S. Department of Energy’s National Nuclear Security Administration (DOE NNSA).
“The pressing challenges of nuclear security and nonproliferation require a concerted effort from experts across the country,” said JoAnn Browning, UTSA interim vice president for research. “We’re thrilled to join this collaborative network of universities and national labs, and I look forward to seeing the impact of our researchers as they leverage AI to make nuclear energy more secure, protecting the integrity of the U.S. nuclear stockpile as well as the collective impact of the broader consortium.”
The consortia were established to facilitate collaboration between university and laboratory researchers to advance science and technology that furthers NNSA's nuclear security and nonproliferation missions, “enabling an effective pipeline of talented next-generation experts to establish careers at DOE national laboratories.” Each consortium will receive up to $5 million per year for five years to further these objectives.
UTSA’s participation will be led by Miltos Alamaniotis, GreenStar Endowed Fellow in Energy and associate professor of electrical and computer engineering. Alamaniotis is an expert in applied artificial Intelligence within the nuclear engineering domain.
This marks the second NNSA consortium that UTSA will participate in to advance nuclear science. In 2019, NNSA provided $3 million in funding for CONNECT (The CONsortium on Nuclear sECurity Technologies), a project engaging investigators from the University of Nevada at Las Vegas, St. Mary’s University, Argonne National Laboratory and Los Alamos National Laboratory.
“The exceptional researchers at UTSA are critical partners in this collaboration,” said Eric Brey, dean of the Klesse College of Engineering and Integrated Design at UTSA. “UTSA is home to world-class researchers and innovators in the nuclear fields. Connecting with our peer institutions and national labs will catalyze our scientific advancements and enhance our students’ experience in this field.”
Alamaniotis is also confident that membership in the consortium will benefit researchers and students.
“This consortium will be an eye-opener for our students, as they will have the chance to interact and collaborate with students from top schools across U.S., while performing high-quality research in a critical field of national and international interest,” he said. “Furthermore, in a consortium of this large scale our students will have the chance to prove themselves and showcase the qualities and capabilities of UTSA.”
Alamaniotis is a co-principal investigator in the consortium and the principal investigator (PI) representing UTSA, where he leads research efforts and prepares students for careers in the nuclear enterprise.
Each PI in the consortium is responsible for contributing to collaborative research as well as leading one research project of their own. Alamaniotis will lead a project that “focuses on developing artificial intelligence algorithms to coordinate the movement of multiple mobile detectors within a metropolitan area to identify hidden radiological threats,” he said.
“This project is particularly challenging due to the presence of naturally occurring ambient radiation and the uncertainty regarding the type of threat,” added Alamaniotis. “Anyone in possession of illicit nuclear material is a threat to our safety. We want to prevent detonation and dispersion of radioactive material within metropolitan areas, and there is only way to accomplish this: detect the material while on the move before it is detonated. We also need to retain privacy in data analysis, as we cannot allow mistakes and wrongly accuse people as potential terrorists. This can only be attained by developing highly sophisticated AI algorithms fed with high-quality datasets.”
The two consortia that are receiving funding from the U.S. Department of Energy will be led by the University of Tennessee, Knoxville and Georgia Institute of Technology respectively.
They include:
Enabling Capabilities in Technology Consortium, led by the University of Tennessee, Knoxville.
This consortium comprises 15 universities and eight national laboratories, including UTSA, the Colorado School of Mines, the Air Force Institute of Technology, Clemson, UC Santa Barbara, University of Hawaiʻi, Louisiana State, MIT, North Carolina State, University of Oklahoma, Oregon State, Texas A&M, University of Utah, Virginia Tech, Idaho National Laboratory, Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Sandia National Laboratories and Savannah River National Laboratory.
Consortium for Enabling Technologies and Innovation, led by Georgia Tech.
This consortium comprises 12 universities in partnership with 12 national laboratories, including Abilene Christian, Colorado School of Mines, MIT, The Ohio State University, Rensselaer Polytechnic Institute, Stony Brook University, Texas A&M, University of Alaska Fairbanks, UT-Austin, University of Wisconsin - Madison, Virginia Commonwealth, Argonne National Laboratory, Brookhaven National Laboratory, Idaho National Laboratory, Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Nevada National Security Site, Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Princeton Plasma Physics Laboratory, Sandia National Laboratories and Savannah River National Laboratory.
The formation of the consortia began in November 2023, when the NNSA released a call for proposals. Interested schools extended invitations to potential collaborators. The University of Tennessee, Knoxville took the initiative to lead the proposal for the consortium that includes UTSA. It identified target research areas and invited individuals, including Alamaniotis, to participate. The NNSA conducted the final selection process, which was highly competitive.
“Our school is renowned for its cybersecurity programs,” added Alamaniotis. “This initiative will establish a new line of research in security, broadening the scope of security research at UTSA in a domain of the utmost importance for our society and future energy sustainability.”
Nitrite-driven anaerobic ethane oxidation
EURASIA ACADEMIC PUBLISHING GROUP
Ethane, an overlooked greenhouse gas, can be oxidized with electron acceptors like sulfate and nitrate. Despite nitrite being a more thermodynamically feasible electron acceptor, little is known about nitrite-driven anaerobic ethane oxidation.
In a study published in Environmental Science and Ecotechnology, a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through long-term operation of a nitrite-and-ethane-fed bioreactor. During continuous operation, the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO2–N L−1 d−1 and 11.48 mg C2H6 L−1 d−1, respectively. Batch tests demonstrated that ethane is essential for nitrite removal in this microbial culture. Metabolic function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae, designated as 'Candidatus Alkanivoras nitrosoreducens', may perform the nitrite-driven anaerobic ethane oxidation. This novel genus is described in full in the paper.
Based on a meta-omic analysis, 'Ca. A. nitrosoreducens' encoded and expressed a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to N2, although the genes for ethane conversion to ethyl-succinate (assAs) and succinate-CoA ligase (sucCD) required further identification.
Phylogenetic affiliation analysis showed a distant genetic relationship between 'Ca. A. nitrosoreducens' and the previously reported 'Candidatus Alkanivorans nitratireducens' that was capable of nitrate-driven anaerobic ethane oxidation, which suggests functional microbial differences in different natural environments.
This study offers new evidence of nitrite-driven anaerobic ethane oxidation occurring in enriched cultures from hot-spring sediment, and describes a novel genus potentially involved in this process .
These findings advance our understanding of nitrite-driven anaerobic ethane oxidation, highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.
A personalized brain-computer interface therapy, RehabSwift, significantly enhances hand mobility for stroke survivors. Strokes often lead to impaired hand function, presenting substantial challenges in daily activities. Sam Darvishi and colleagues developed and tested a brain-computer interface therapy that translates imagined hand movements into real actions using a personalized algorithm and bionic hands. The study involved twelve chronic stroke survivors from South Australia who had limited use of their arms but retained clear thinking abilities. Throughout 18 sessions, participants used the RehabSwift system, which included a special cap that measured their brain activity. Participants imagined moving their fingers, and this brain activity was then translated into actual finger movements by bionic hands providing both visual and physical feedback. Participants showed improvements in various areas, including overall arm function, hand movement tests, reaction times, and hand strength. These gains were maintained at follow-up assessments 4 ̶ 6 weeks after training. Many participants reported achieving their mobility goals after the training. According to the authors, these findings highlight the potential of brain-computer interfaces as powerful, personalized, and adaptable tools for stroke rehabilitation.
JOURNAL
PNAS Nexus
ARTICLE TITLE
Enhancing poststroke hand movement recovery: Efficacy of RehabSwift, a personalized brain–computer interface system
ARTICLE PUBLICATION DATE
9-Jul-2024
COI STATEMENT
Sam Darvishi is the founder of and a shareholder of RehabSwift Pty Ltd, who made available their system for the duration of the study and paid for the consumables and the salary of the personnel who assisted with the governance of the clinical trials. Other authors were not paid by RehabSwift and declare no conflict of interest.
