Tyler O'Neal, Staff Editor ECONOMICS

New Russian built system transmits high-speed unrepeated signal over 520 kilometers

Researchers from the Moscow Institute of Physics and Technology in Russia have partnered up with engineers from Corning Inc., U.S., and T8, Russia, and developed a system for high-throughput data transfer over great distances without the need for signal repeating along the way. Systems of this kind could be used to provide internet connection and other communication services in remote communities. The study is reported in an educational journal.

Countries with large underpopulated areas -- such as Russia and Canada -- or those comprised by numerous islands, like Indonesia, face difficulties in providing communication services. Without intermediate electricity-powered repeater stations, the signal gets attenuated and does not arrive at the destination. To make long-haul data transmission cheaper, engineers come up with fiber optic systems that amplify the signal along the link without the need for electrical power sources. Top transmission systems available today enable data transfer at the rate of 100 gigabits per second across 500 kilometers (311 miles).

The authors of the letter successfully transmitted a signal over 520 km (323 mi) at 200 Gbps. This had only been done in research labs before, but those results could not be carried over to actual applications. This time commercial cables developed by Corning were used, making the technology applicable under realistic conditions. To avoid the attenuation of the signal, it was amplified initially upon transmission and then two more times remotely, along the way. The newly developed Volga platform enables high-speed transmission lines spanning over 520 kilometers, or 323 miles.{module INSIDE STORY}

"To amplify the signal in the passive fiber, the stimulated Raman scattering effect and remote optically pumped amplifiers were used. The Raman scattering effect allowed us to use the passive optical fiber as an amplification medium, considerably increasing the signal-to-noise ratio at link output," explained the study's lead author Dimitriy Starykh, a PhD student at MIPT's Phystech School of Radio Engineering and Computer Technology.

The transmission line comprised three sections, each consisting of fiber optic cables of two types connected in series. Remote optically pumped erbium amplifiers (ROPA) were installed at the points of junction between the sections. ROPAs consume optical pump and use this energy to amplify signal. The team optimized the junction positions to increase output signal quality, placing the two ROPAs 122 km (76 mi) from the transmitter and 130 km (81 mi) from the receiver, respectively.

The researchers set the signal symbol rate to slightly short of 57 billion pulses per second; the transmitter allowed the transfer of five bits per symbol, enabling a total bit rate of 284 Gbps. While the system potentially supported data transfer at up to 400 Gbps, the engineers ran it at a reduced speed to increase the transmission distance.

"We are already working on a fiber optic system that would achieve higher transfer rates. While the current speed tops at about 400 Gbps, we aim to reach 600 Gbps per channel with the new system," T8 CEO Vladimir Treshchikov commented. "We achieved signal improvement for rates of 200 Gbps and even 400 Gbps per channel. I think, next year we could set a further transmission distance record."

The results achieved by the researchers can already be employed to provide communication services in sparsely populated areas, such as the Russian island Sakhalin.

NC State's model identifies high-risk areas for lumpy skin disease in cattle

Tyler O'Neal, Staff Editor ECONOMICS

Researchers have combined two separate supercomputer models to identify areas at the highest risk for outbreaks of lumpy skin disease virus (LSDV) in cattle. The models could help officials determine where to send resources ahead of outbreaks and serve as a potential early warning system for cattle farmers in affected areas.

LSDV is a disease that affects cattle. Current research points to transmission via biting insects such as flies, fleas, ticks or mosquitoes. Infected calves may die, and older cattle develop bleeding circular lesions on the skin, decreased milk production, and overall poor health.

Although LSDV is endemic to Africa since 2015 the disease has spread into the Northern Hemisphere including Azerbaijan, Kazakhstan, the Russian Federation, and the Balkans. The rapid expansion of LSDV in those regions shows the virus can thrive in more temperate regions than those in which LSDV traditionally occurred. {module In-article} 

"LSDV represents an emerging threat to international trade of livestock products and live animals, due to the economic impact of milk and beef production losses," says Gustavo Machado, assistant professor of population health and pathobiology at NC State and corresponding author of a paper describing the work. "The good news is that the disease can be controlled by vaccination. However, we need a way to efficiently target our prevention efforts."

Machado and an international team of colleagues combined two different supercomputer models - a risk model that examined the spatiotemporal dynamics within affected areas and a suitability model that looked at ecological conditions in affected areas - to determine where the virus would be most likely to thrive. Focusing on data from 2014 to 2016, before vaccination protocols began, the team divided study areas into 20 by 20-kilometer portions and fed information on cattle numbers and ecological conditions into the integrated model.

The model identified elevated risk areas in Russia, Turkey, Serbia, and Bulgaria. The risk was positively associated with precipitation and temperature and negatively affected by wind. Results suggest that if current ecological and epidemiological conditions persist, further spread of LSDV in Eurasia may be expected.

"Although there is little risk of airborne transmission of LSDV, if ecological conditions are favorable for the insects that can transmit it, the disease can spread - even in areas where there isn't a particularly large cattle population," Machado says.

Although LSDV hasn't yet been reported in the U.S., Machado says his model could easily be used to predict high-risk areas if an outbreak occurs. "We don't want LSDV to have the devastating impact on the cattle industry that African swine fever is having on the pork industry," he says. "Models like this one are necessary to help farmers and agricultural agencies stay ahead of the disease curve."