Connect with us

Bioengineer

Global analysis suggests COVID-19 is seasonal

Credit: L. Brian Stauffer, University of Illinois URBANA, Ill. – With cities around the globe locking down yet again amid

Published

on

Credit: L. Brian Stauffer, University of Illinois

URBANA, Ill. – With cities around the globe locking down yet again amid soaring COVID-19 numbers, could seasonality be partially to blame? New research from the University of Illinois says yes.

In a paper published in Evolutionary Bioinformatics, Illinois researchers show COVID-19 cases and mortality rates, among other epidemiological metrics, are significantly correlated with temperature and latitude across 221 countries.

“One conclusion is that the disease may be seasonal, like the flu. This is very relevant to what we should expect from now on after the vaccine controls these first waves of COVID-19,” says Gustavo Caetano-Anollés, professor in the Department of Crop Sciences, affiliate of the Carl R. Woese Institute for Genomic Biology at Illinois, and senior author on the paper.

The seasonal nature of viral diseases is so widespread that it has become part of the English vernacular. For example, we often speak of the “flu season” to describe the higher incidence of influenza during the cold winter months. Early in the pandemic, researchers and public health officials suggested SARS-CoV-2 may behave like other coronaviruses, many of which rear their heads in fall and winter. But data was lacking, especially on the global scale. The work of Caetano-Anollés and his students fills that specific knowledge gap.

First, the researchers downloaded relevant epidemiological data (disease incidence, mortality, recovery cases, active cases, testing rate, and hospitalization) from 221 countries, along with their latitude, longitude, and average temperature. They pulled the data from April 15, 2020, because that date represents the moment in a given year in which seasonal temperature variation is at its maximum across the globe. That date also coincided with a time during the early pandemic when COVID-19 infections were peaking everywhere.

The research team then used statistical methods to test if epidemiological variables were correlated with temperature, latitude, and longitude. The expectation was that warmer countries closer to the equator would be the least affected by the disease.

“Indeed, our worldwide epidemiological analysis showed a statistically significant correlation between temperature and incidence, mortality, recovery cases, and active cases. The same tendency was found with latitude, but not with longitude, as we expected,” Caetano-Anollés says.

While temperature and latitude were unmistakably correlated with COVID-19 cases, the researchers are quick to point out climate is only one factor driving seasonal COVID-19 incidence worldwide.

They accounted for other factors by standardizing raw epidemiological data into disease rates per capita and by assigning each country a risk index reflecting public health preparedness and incidence of co-morbidities in the population. The idea was that if the disease was surging in countries with inadequate resources or higher-than-average rates of diabetes, obesity, or old age, the risk index would appear more important in the analysis than temperature. But that wasn’t the case. The index did not correlate with the disease metrics at all.

Earlier work from Caetano-Anollés and his coworkers identified areas in the SARS-CoV-2 virus genome undergoing rapid mutation, some represented in the new virus variant out of Britain, and other genomic regions becoming more stable. Since similar viruses show seasonal upticks in mutation rates, the research team looked for connections between mutational changes in the virus and temperature, latitude, and longitude of the sites from which genomes were sampled worldwide.

“Our results suggest the virus is changing at its own pace, and mutations are affected by factors other than temperature or latitude. We don’t know exactly what those factors are, but we can now say seasonal effects are independent of the genetic makeup of the virus,” Caetano-Anollés says.

Caetano-Anollés notes more research is needed to explain the role of climate and seasonality in COVID-19 incidences, but he suggests the impact of policy, such as mask mandates, and cultural factors, such as the expectation to look out for others, are key players as well. However, he doesn’t discount the importance of understanding seasonality in battling the virus.

The researchers say our own immune systems could be partially responsible for the pattern of seasonality. For example, our immune response to the flu can be influenced by temperature and nutritional status, including vitamin D, a crucial player in our immune defenses. With lower sun exposure during the winter, we don’t make enough of that vitamin. But it’s too soon to say how seasonality and our immune systems interact in the case of COVID-19.

“We know the flu is seasonal, and that we get a break during the summer. That gives us a chance to build the flu vaccine for the following fall,” Caetano-Anollés says. “When we are still in the midst of a raging pandemic, that break is nonexistent. Perhaps learning how to boost our immune system could help combat the disease as we struggle to catch up with the ever-changing coronavirus.”

###

The article, “Temperature and latitude correlate with SARS-CoV-2 epidemiological variables but not with genomic change worldwide,” is published in Evolutionary Bioinformatics [DOI: 10.1177/1176934321989695]. Authors include Prakruthi Burra, Katiria Soto-Díaz, Izan Chalen, Rafael Jaime Gonzalez-Ricon, Dave Istanto, and Gustavo Caetano-Anollés. The work was supported by the Office of Research and the Office of International Programs in the College of Agricultural, Consumer and Environmental Sciences at the University of Illinois at Urbana-Champaign.

“One conclusion is that the disease may be seasonal, like the flu. This is very relevant to what we should expect from now on after the vaccine controls these first waves of COVID-19,” says Gustavo Caetano-Anollés, professor in the Department of Crop Sciences, affiliate of the Carl R. Woese Institute for Genomic Biology at Illinois, and senior author on the paper.

Source: https://bioengineer.org/global-analysis-suggests-covid-19-is-seasonal/

global-analysis-suggests-covid-19-is-seasonal

Bioengineer

Benefits of AstraZeneca COVID-19 vaccine outweigh its risks

Pausing AstraZeneca vaccinations because of suspected links to deadly blood clots could allow COVID-19 to continue to spread, cause more

Published

on

Pausing AstraZeneca vaccinations because of suspected links to deadly blood clots could allow COVID-19 to continue to spread, cause more deaths.

Credit: Davide Faranda, Tommaso Alberti, Maxence Arutkin, Valerio Lembo, and Valerio Lucarini

WASHINGTON, April 27, 2021 — The AstraZeneca COVID-19 vaccine is suspected of being linked to a small number of deep vein thrombosis (DVT) cases, which recently emerged within Europe as millions of people received vaccinations. This led several countries to suspend AstraZeneca injections and investigate the causal links to DVT.

Researchers within Europe teamed up to explore a hypothesis that pausing AstraZeneca vaccinations, even for a short duration, could cause additional deaths from the faster spread of COVID-19 within a population of susceptible individuals.

In Chaos, from AIP Publishing, researchers report using an epidemiological susceptible-exposed-infected-recovered (SEIR) model and statistical analysis of publicly available data to estimate excess deaths resulting from suspending AstraZeneca vaccinations and those potentially linked to DVT-adverse events in France and Italy.

They concluded the benefits of deploying the AstraZeneca vaccine greatly outweigh its associated risks, and relative benefits are wider in situations where the reproduction number is larger.

The SEIR model was discussed in a paper, published by Chaos, titled “Modeling the second wave of COVID-19 infections in France and Italy via a stochastic SEIR model.” It was able to predict the magnitude and timing of the second wave of the disease in France and Italy.

“Despite its simplicity, the model is able to propagate uncertainties via adding interactivity as a source of randomness within the data,” said Davide Faranda, from Laboratoire des Sciences du Climat et de l’Environnement and the London Mathematical Laboratory. “It mimics our ignorance of the exact parameters of the model due to testing capacities and evolving political and medical protocols.”

Risk-benefit analysis is performed by using a methodology inspired by the Fermi estimates. The group compares the excess deaths due to temporal restriction of the AstraZeneca vaccine’s deployment and excess deaths due to its possible side effects. Given the many uncertainties of possible side effects of the vaccine, they resorted to making worst-case scenario calculations to provide a robust upper bound to the related excess deaths.

“Our work shows suspending AstraZeneca vaccinations in France and Italy for three days without replacing it with another vaccine led to about 260 and 130 additional deaths, respectively,” said Faranda. “The difference between the two countries’ number of deaths is due to their different epidemiological situations and, in particular, to the higher basic reproduction number R0 measured in Italy with respect to France on March 15, 2021.”

The group analyzed the case of resuming vaccinations at a doubled rate for the same number of days as the vaccination interruption.

“Excess deaths are still on the same order of magnitude as those observed by resuming vaccinations at the same rate as before the interruption but scaled down by a factor of two,” said Faranda. “This is an evident outcome of nonlinear effects of epidemiological dynamics. Those who have not been vaccinated can contaminate other individuals before vaccination resumes.”

Even if several countries have resumed or are about to resume AstraZeneca vaccinations, the researchers show the effect of the interruption is hard to counterbalance and will require doubling down on deployment of vaccines. For large countries where AstraZeneca vaccinations have resumed, confidence in vaccines has been reduced by a nonnegligible percentage.

“The analysis presented here was performed with a parsimonious but well posed and tested model, and we hope our results will be the starting point for more detailed, more advanced, and more mature investigations with sophisticated models and data collection exercises,” said Faranda.

A first proof of the validity of their estimates is the report of seven DVT deaths per 18 million vaccinations within the U.K., a value that is in line with the group’s work based on data available a few weeks ago and assuming a standard fatality rate of DVT from AstraZeneca vaccinations.

###

The article “Interrupting vaccination policies can greatly spread SARS-CoV-2 and enhance mortality from COVID-19 disease: The AstraZeneca case for France and Italy” is authored by Davide Faranda, Tommaso Alberti, Maxence Arutkin, Valerio Lembo, and Valerio Lucarini. It will appear in Chaos on April 27, 2021 (DOI: 10.1063/5.0050887). After that date, it can be accessed at https://aip.scitation.org/doi/10.1063/5.0050887.

ABOUT THE JOURNAL

Chaos is devoted to increasing the understanding of nonlinear phenomena in all areas of science and engineering and describing their manifestations in a manner comprehensible to researchers from a broad spectrum of disciplines. See https://aip.scitation.org/journal/cha.

Researchers within Europe teamed up to explore a hypothesis that pausing AstraZeneca vaccinations, even for a short duration, could cause additional deaths from the faster spread of COVID-19 within a population of susceptible individuals.

Source: https://bioengineer.org/benefits-of-astrazeneca-covid-19-vaccine-outweigh-its-risks/

benefits-of-astrazeneca-covid-19-vaccine-outweigh-its-risks

Continue Reading

Bioengineer

Army technique enhances robot battlefield operations

Credit: (Photo illustration / U.S. Army) ADELPHI, Md. — Army researchers developed a technique that allows robots to remain resilient

Published

on

Credit: (Photo illustration / U.S. Army)

ADELPHI, Md. — Army researchers developed a technique that allows robots to remain resilient when faced with intermittent communication losses on the battlefield.

The technique, called α-shape, provides an efficient method for resolving goal conflicts between multiple robots that may want to visit the same area during missions including unmanned search and rescue, robotic reconnaissance, perimeter surveillance and robotic detection of physical phenomena, such as radiation and underwater concentration of lifeforms.

Researchers from the U.S. Army Combat Capabilities Development Command, known as DEVCOM, Army Research Laboratory and the University of Nebraska, Omaha Computer Science Department collaborated, which led to a paper featured in ScienceDirect’s journal Robotics and Autonomous Systems.

“Robots working in teams need a method to ensure that they do not duplicate effort,” said Army researcher Dr. Bradley Woosley. “When all robots can communicate, there are many techniques that can be used; however, in environments where the robots cannot communicate widely due to needing to stay covert, clutter leading to radios not working for long distance communications, or to preserve battery or bandwidth for more important messages, the robots will need a method to coordinate with as few communications as possible.”

This coordination is accomplished through sharing their next task with the team, and select team members will remember this information, allowing other robots to ask if any other robot will perform that task without needing to communicate directly with the robot that selected the task, Woosley said.

The robot that remembers a task is based on the topology of their wireless communications network and the geometric layout of the robots, he said. Each robot is assigned a bounding shape representing the area of the environment that they are caching goal locations for, which enables a quick search in the communications network to find the robot that would know if there were any goals requested in that area.

“This research enables coordination between robots when each robot is empowered to make decisions about its next tasks without requiring it to check in with the rest of the team first,” Woosley said. “Allowing the robots to make progress towards what the robots feel is the most important next step while handling any conflicts between two robots as they are discovered when robots move in and out of communications range with each other.”

The technique uses a geometric approximation called α-shape to group together regions of the environment that a robot can communicate with other robots using multi-hop communications over a communications network. This technique is integrated with an intelligent search algorithm over the robots’ communication tree to find conflicts and store them even if the robot that selects the goal disconnects from the communication tree before reaching the goal.

The team reported experimental results on simulated robots within multiple environments and physical Clearpath Jackal Robots.

“To our knowledge, this work is one of the first attempts to integrate geometry-based prediction of potential conflict regions to improve multi-robot information collection under communication constraints, while gracefully handling intermittent connectivity loss between robots,” Woosley said.

According to Woosley, other available approaches can only get input from the robots that are inside the same communications network, which is less efficient when robots can move in and out of communications range with the team.

In contrast, he said, this research provides a mechanism for the robot to quickly find potential conflicts between its goal and the goal another robot selected, but is not in the communications network anymore.

What specifically makes this research unique includes:

    -Providing an efficient method (fast and with few messages) for resolving goal conflicts between multiple robots that is robust to intermittent communications loss and robots joining or leaving local sets of robots that are in communications with each other

    -Performing as good as querying every robot in the communications range while saving radio bandwidth for more important communications

    -Performing better than each robot operating fully on its own without communications

Woosley said that he is optimistic this research will pave the way for other communications limited cooperation methods that will be helpful when robots are deployed in a mission that requires covert communications.

He and the research team, including DEVCOM ARL researchers Dr. John Rogers and Jeffrey Twigg and Naval Research Laboratory research scientist Dr. Prithviraj Dasgupta, will continue to work on collaboration between robotic team members through limited communications, especially in directions of predicting the other robot’s actions in order to avoid conflicting tasks to begin with.

###

Source: https://bioengineer.org/army-technique-enhances-robot-battlefield-operations/

army-technique-enhances-robot-battlefield-operations

Continue Reading

Bioengineer

Skoltech and MIT researchers identify optimal human landing system architectures to land on the Moon

Credit: Pavel Odinev (Skoltech) Researchers from Skoltech and the Massachusetts Institute of Technology have analyzed several dozen options to pick

Published

on

Researchers from Skoltech and the Massachusetts Institute of Technology have analyzed several dozen options to pick the best one in terms of performance and costs for the ‘last mile’ of a future mission to the Moon – actually delivering astronauts to the lunar surface and back up to the safety of the orbiting lunar station. The paper was published in the journal Acta Astronautica.

Ever since December 1972, when the crew of Apollo 17 left the lunar surface, humans have been eager to return to the Moon. In 2017, the US government launched the Artemis program, which intends to bring “the first woman and the next man” to the lunar south pole by 2024. The Artemis mission will use a new orbital platform, dubbed the Lunar Gateway, which is going to be a permanent space station from which reusable modules will bring astronauts back to the Moon. This new approach requires a reanalysis of the optimal landing approaches; the private companies contracted by NASA to design the reusable landing modules are conducting this research, but keeping their findings to themselves.

Skoltech M.Sc. student Kir Latyshev, Ph.D. student Nicola Garzaniti, Associate Professor Alessandro Golkar, and MIT’s Edward Crawley developed mathematical models to assess the most promising options for human landing systems for a future Artemis mission. For instance, the Apollo program used 2-stage architecture, when the Apollo Lunar Module, consisting of a descent and ascent modules, was able to carry two people to the lunar surface and back up, leaving the descent module behind.

The team assumed the Lunar Gateway is located in the L2 near rectilinear halo orbit, the currently preferred option that has the station orbiting the L2 Lagrange point in a way that makes it easier to land on the lunar south pole. They also modeled an expedition of four astronauts, who will spend around seven days on the Moon. The scientists considered both the optimal number of stages and the preferred propellants for the system. In total, they went through 39 variants of the future lunar human landing system, also modeling the cost for the most promising options.

The team went through a comprehensive approach for assessing alternative concepts of lunar human landers, looking at a broad number of options using architectural screening models. They first defined the key set of architectural decisions to be taken, such as number of stages and propellant type to be employed at each stage of the lander. They organized the information in mathematical models, and performed a comprehensive computational exploration of alternative system architectures coming from the combination of the different architectural decisions. Finally, they analyzed the resulting tradespace and identified preferred architectures for consideration by stakeholders concerned with the design of human lunar landers.

Their analysis showed that for expendable landing systems such as the ones used in the Apollo program, the 2-stage architecture is indeed the most advantageous as it has both lower total dry masses and propellant loads as well as lower launch costs per mission. However, for reusable vehicles planned for the Artemis program, 1-stage and 3-stage systems quickly become comparable in their advantages.

With all assumptions in the paper considered, the ‘ultimate’ winner for a number of short ‘sortie’-type lunar missions is the 1-stage reusable module running on liquid oxygen and liquid hydrogen (LOX/LH2). The authors note that this is a preliminary analysis, which does not take into account crew safety, probability of mission success as well as project management risks considerations – these will require more elaborate modeling at a later stage of the program.

Kir Latyshev notes that, for the Apollo program, NASA engineers did a similar analysis and chose the 2-stage lunar module. However, the overall architecture of lunar missions was different back then. It did not have an orbiting lunar station to keep the lunar module at between the missions, which meant that all ALM flights should be performed directly from Earth. It also meant using fully expendable lunar modules (a new vehicle for each mission), as opposed to reusable ones considered nowadays. Apart from that, without the lunar station, one of the current options – the 3-stage landing system – was not possible at all.

“Interestingly, our study finds that, even with the orbiting station, if fully expendable vehicles are considered, then the 2-stage (Apollo-like) landing system is still expected to have lower masses and, therefore, lower costs – which sort of reconfirms the Apollo decision. However, reusability changes that. Though 1-stage and 3-stage vehicles in this case are still heavier than the 2-stage one, they allow to reuse more of the ‘vehicle mass’ (approximately 70-100% compared to around 60% for the 2-stage option) over and over again, thus saving money on producing and delivering new vehicles to the orbiting station and making lunar missions potentially cheaper,” Latyshev says.

He adds that crew safety consideration is an important factor in designing human space systems which the authors did not account for in their study. “This safety factor can affect the results in either way. For example, multi-stage solutions might offer more safe return opportunities in case of emergency in the parking lunar orbit prior to descent to the surface than our ‘winner’, the 1-stage system: either the descent or ascent vehicle can be used for return in case of 3-stage and 2-stage systems as opposed to the single stage of the 1-stage system. At the same time, 2-stage and 3-stage systems are expected to be more complex and therefore to have more risks of breakdowns, as opposed to the simpler 1-stage solution. So there is a trade-off again,” Latyshev explains.

The team plans to expand the work in the future, with a comprehensive exploration of the system architecture of the entire exploration infrastructure required in future human spaceflight programs for lunar exploration.

###

https://www.skoltech.ru/en/2021/03/skoltech-and-mit-researchers-identify-optimal-human-landing-system-architectures-to-land-on-the-moon/

The team went through a comprehensive approach for assessing alternative concepts of lunar human landers, looking at a broad number of options using architectural screening models. They first defined the key set of architectural decisions to be taken, such as number of stages and propellant type to be employed at each stage of the lander. They organized the information in mathematical models, and performed a comprehensive computational exploration of alternative system architectures coming from the combination of the different architectural decisions. Finally, they analyzed the resulting tradespace and identified preferred architectures for consideration by stakeholders concerned with the design of human lunar landers.

Source: https://bioengineer.org/skoltech-and-mit-researchers-identify-optimal-human-landing-system-architectures-to-land-on-the-moon/

skoltech-and-mit-researchers-identify-optimal-human-landing-system-architectures-to-land-on-the-moon

Continue Reading

Title

Cointelegraph11 mins ago

VanEck and BetaShares apply for Aussie crypto ETFs as family offices snap up BTC

VanEck and BetaShares have lodged submissions with the ASX for Bitcoin and crypto-related funds.

Ventureburn12 hours ago

West African tech startup launches app in Gabon 

West African tech startup Gozem has announced the launch of 'Super App' taxi booking service in Libreville enabling consumers to travel...

Business insider15 hours ago

Spark Networks Announces Conference Call to Discuss First Quarter 2021 Results

BERLIN, May 5, 2021 /PRNewswire/ -- Spark Networks SE (NYSE: LOV), one of the world's leading online dating companies, announced today that...

Coinpedia18 hours ago

Dogecoin Price Close 70 Cents, Will the Whales Allow Rally To Hit $1?

Dogecoin price rallies more than 50% for the second consecutive day, may smash $1. The doge price may flip BNB...

Bioengineer20 hours ago

Benefits of AstraZeneca COVID-19 vaccine outweigh its risks

Pausing AstraZeneca vaccinations because of suspected links to deadly blood clots could allow COVID-19 to continue to spread, cause more

Reuters23 hours ago

U.S. Commerce Dept. pressing Taiwan to supply more chips to U.S. automakers

The U.S. Commerce Department is pressing Taiwan Semiconductor Manufacturing Co Ltd (2330.TW) and other Taiwanese firms to prioritize the needs...

Blockchain news1 day ago

Total Value Locked in Maker Reaches a Record High as Maker Foundation Returns Dev Fund to DAO

Maker's total value locked (TVL) surged to $12.02B, hitting a record high amid Maker Foundation's announcement that it would refund...

Techcrunch2 days ago

Indian online teaching platform Teachmint raises $16.5 million – TechCrunch

An Indian startup that began its life after the global pandemic broke last year said on Tuesday it has concluded...

ZDNET2 days ago

Adobe Flash: Microsoft lays out plans to remove it from Windows 10 PCs for good

Microsoft's July Patch Tuesday security update will include the Flash removal update for all versions of Windows 10.

CNBC2 days ago

Berkshire Hathaway’s annual meeting is here: What to expect from Warren Buffett and Charlie Munger

The 90-year-old Buffett is taking the "Woodstock for Capitalists" to Los Angeles, marking the first time the annual meeting will...

Review

    Select language

    Trending