HAMNET Report 29 July 2018

Noting the wildfires in UK, Sweden, Latvia, and especially in Greece, and that the European Civil Protection mechanism has been activated in some cases with support from other EU countries such as the Polish Fire Service sending assistance to Sweden, Greg Mossop G0DUB has wondered if any groups have been asked to support their emergency services.

Reports from Greece, Ireland and Germany revealed no participation, but Michal Wilczynski SP9XWM in Poland reported that their fires had rapidly been brought under control by their local fire brigades; and that their special Fire Brigade, consisting of 139 firemen and 44 rescue vehicles, had started to help people in Sweden to fight the flames, and are available to help the citizens of Greece. Very good cross-border cooperation from Poland!

The World Health Organisation has announced that the 24th July marks the end of the ninth outbreak of Ebola in the Democratic Republic of Congo (DRC). WHO Director-General, Dr Tedros Adhanom Ghebreyesus, and Regional Director for Africa, Dr Matshidiso Moeti, joined Minister of Health Dr Oly Ilunga for the announcement in Kinshasa.

“The outbreak was contained due to the tireless efforts of local teams, the support of partners, the generosity of donors, and the effective leadership of the Ministry of Health. That kind of leadership, allied with strong collaboration between partners, saves lives,” said Dr Tedros.

Within hours of the outbreak being declared on 8 May, WHO released US$2 million from its Contingency Fund for Emergencies, deployed a team to augment capacity in the field, and activated an emergency incident management system.

“WHO moved quickly and efficiently,” said Dr Moeti, “We also demonstrated the tremendous capacity of the African region. More than three-quarters of the 360 people deployed to respond came from within the region. Dozens of experts from Guinea spent weeks leading Ebola vaccination efforts here, transferring expertise which will enable the DRC to mount an effective response both within its borders and beyond.”

“This effective response to Ebola should make the Government and partners confident that other major outbreaks affecting the country such as cholera and polio can also be tackled,” said Dr Tedros. “We must continue to work together, investing in strengthened preparedness and access to healthcare for the most vulnerable.”

In Appateu, Laos, the rescue of a baby boy, terrified and hungry after days without food, has been captured in a viral video showing the infant survivor of a dam collapse in southern Laos being carefully carried through swirling flood waters and waist-high mud.

Footage of volunteers from Thailand rescuing 14 people, including the baby, went viral when it was released this Friday as an increasingly international relief mission scrambles to save lives in a disaster that has left scores dead and missing.

The survivors were stranded by flood waters after they fled up a hill on Monday as the Xe-Namnoy dam broke under heavy rain, leaving several villages devastated by flash floods.

The Thai team, who waded several kilometres through rushing water, carrying uprooted trees and debris, to rescue the group, are fresh from efforts to help free the youth football team trapped in a cave in the north of their country.

They have now come to help out in neighbouring Laos, which is poorly equipped to deal with natural disasters of this scale.

“The boy is four months old. He didn’t have fever but he was crying, maybe because of the cold weather,” Kengkard Bongkawong, one of the rescuers, who is from Thailand’s northeast, told AFP.

“The baby was crying and looked terrified. Actually survivors were (all) still terrified of the rushing water.”

Earlier this week officials said 27 bodies had been retrieved so far, with the country’s prime minister reporting 131 missing.

But on Friday the governor of Attapeu province Leth Xiayaphone revised down the toll to five, saying the larger number previously given was “unconfirmed information”.

Authorities in Laos are not used to international scrutiny, and have blocked access to foreign media, complicating efforts to establish the exact death toll.

Now, here’s a good news story about the use of drones. I have previously reported on the use of drones to assess disaster damage, and aid in rescue planning.

Well, TV20’s reporter Landon Harrar, reporting in wcjb.com, said that ” the drones aren’t just being used to map flooded areas. They, in fact, have many other uses including environmental ones, some that have to deal with wildlife.”

David Peaton, Levy County’s Assistant Director of Emergency Management, gave an example of this happening. “We had this birds nest at the top of one of our old communications towers which our public safety department had determined we had to tear down. Well, we wanted to make sure there were no active eggs in it, and that it was no longer being used. So instead of paying someone hundreds if not thousands of dollars to climb this tower, we decided to fly the drone up there and check the nest out.” The nest was empty and the tower came down! Well done, Levy County.

I hope most of you seized the opportunity on Friday evening  to watch our nearest celestial neighbour go through a change in colour-scheme. I refer of course to the Lunar Eclipse, visible to all of South Africa, most of which seems to have been free of cloud, allowing good viewing.

During the peak of the eclipse, examination of the moon through binoculars would have revealed stars in the near background, not normally visible when the moon is fully bright. And nearby, clearly visible, Mars seemed to shine even more brightly as the moon’s colour changed to a deep “blood” colour. In  fact, at moonrise, Jupiter was visible directly above us, and Venus just setting to the West, chasing after the Sun. It was a wonderful night for star-gazing, and I hope some of you experimented with your DSLR cameras and telephoto lenses, trying to get some decent memories of the event. The next eclipse of similar proportions for South Africa will take place only in 2025.

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.

HAMNET Report 22 July 2018

The website phys-org tells us that, for scientists watching the Red Planet Mars from data gathered by NASA’s orbiters, the past month has been a windfall. “Global” dust storms, where a runaway series of storms creates a dust cloud so large it envelops the planet, only appear every six to eight years (that’s three to four Mars years). Scientists still don’t understand why or how exactly these storms form and evolve.

In June, one of these dust events rapidly engulfed the planet. Scientists first observed a smaller-scale dust storm on May 30. By June 20, it had gone global.

For the Opportunity rover, that meant a sudden drop in visibility from a clear, sunny day to that of an overcast one. Because Opportunity runs on solar energy, scientists had to suspend science activities to preserve the rover’s batteries. As of July 18th, no response has been received from the rover.

Luckily, all that dust acts as an atmospheric insulator, keeping night-time temperatures from dropping down to lower than what Opportunity can handle. But the nearly 15-year-old rover isn’t out of the woods yet: it could take weeks, or even months, for the dust to start settling. Based on the longevity of a 2001 global storm, NASA scientists estimate it may be early September before the haze has cleared enough for Opportunity to power up and call home.

When the skies begin to clear, Opportunity’s solar panels may be covered by a fine film of dust. That could delay a recovery of the rover as it gathers energy to recharge its batteries. A gust of wind would help, but isn’t a requirement for a full recovery..

While the Opportunity team waits in earnest to hear from the rover, scientists on other Mars missions have gotten a rare chance to study this head-scratching phenomenon.

The Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiters are all tailoring their observations of the Red Planet to study this global storm and learn more about Mars’ weather patterns. Meanwhile, the Curiosity rover is studying the dust storm from the Martian surface.

In other news, the race to produce safe, powerful and affordable solid-state lithium batteries is accelerating and recent announcements about game-changing research using a solid non-flammable ceramic electrolyte known as garnet has some in the race calling it revolutionary.

“This is a paradigm shift in energy storage,” said Kelsey Hatzell, assistant professor of mechanical engineering. A paper describing her novel research on the failure points of a garnet electrolyte was published online in March in the American Chemical Society’s Energy Letters, which was among the most read ACS Letters articles that month.

Lithium-ion batteries typically contain a liquid organic electrolyte that can catch fire. The fire risk is eliminated by the use of a non-flammable garnet-based electrolyte. Replacing liquid electrolytes with a solid organic like garnet also potentially lowers the cost by increasing battery life.

“Solid-state batteries are desirable for all-electric vehicles and other applications where energy storage and safety are paramount,” Hatzell said.

Hatzell’s team tested Lithium lanthanum Zirconium Oxide or LLZO – a garnet-type material that shows great promise for all-solid-state battery applications due to its high Li-ion conductivity and its compatibility with Li metal.

“Understanding the failure mechanisms within these electrolyte systems is critical for designing resilient solid electrolyte systems,” said Hatzell.

I’m hoping that the search for the ideal lithium-based battery system that is light-weight and long-lasting is almost over. Thanks to phys-org for these inserts.

The ARES E-letter reports that, for the first time in the history of amateur communications support of Cooperstown, New York, area public events, high speed video and other data networking on the microwave bands were employed, implementing a mesh network in conjunction with the more traditional simplex VHF FM operations. In the past, the Cooperstown Triathlon run that courses through picturesque Glimmerglass State Park has been supported by Otsego County ARES/RACES with traditional VHF ops, but this year the group added amateur high speed video, enabling remote monitoring of the wooded race course, providing an enhanced, significant situational awareness for race officials.

With the leadership of John Rudolph, N2YP, of Unadilla, New York, and Brian Webster, N2KGC, of Cooperstown, a local area network was established to provide remote control and image transmission to and from remote TV cameras. The main net control station was set up at race headquarters, with the cameras placed at strategic sites around the race course. The real-time video was monitored by the race coordinators.

Along with the employment of the video system, the usual VHF FM portables were also deployed: A simplex frequency was used with backup of the 146.640 MHz Cooperstown repeater for the operators assisting officials with race participant and spectator safety.

The video links/networking used the mesh mode. Remote control of the cameras included full tilt and pan capabilities. Signal to noise ratios were good, and imaging was clear and smooth.

The amateur bands at 900 MHz, 2.4 GHz, 3.4 GHz and 5 GHz can be employed, with the Otsego group using 2.4 GHz channels for its network nodes.

There was absence of interference and a low noise floor, increasing the range of the small transmitters. The use of high-gain antennas at both ends helped with signal strengths, image quality, and hence, efficiency. Inexpensive Internet-protocol (IP) cameras were employed. The 5 GHz band was reserved as a backup, but its use was found to be unnecessary.

A portion of the network build was simply the firmware uploaded to the Ubiquiti® 2.4 GHz radios. Since the radios are designed to work in frequency bands all over the world, the firmware can take advantage of the radio’s ability to move to the amateur portions of the bands readily.

Thank you to ARES for these extracts from their newsletter.

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.



HAMNET Report 15 July 2018

The International Amateur Radio Union Region One website carries news of the YOTA 2018 in South Africa week, to be held in August. Nico, ZS6QL, President of the SARL writes that the event will be held in the beautiful central region of Gauteng at the Kopanong Hotel and Conference Centre easily accessible from the O.R. Tambo International Airport in Johannesburg.

The week will offer many opportunities to learn more about amateur radio and getting to know fellow amateurs from various other countries.
Highlights planned for the week include learning about SDR technology with your own SDR dongle, building a mini CubeSat and experiencing launching it as well as tracking it into near space on a high altitude balloon. Also, learning about Rapid Deployment Amateur Radio (RaDAR), which is in essence amateur radio on the move, and building a QRP HF transceiver kit.

Then there will be a visit to a game reserve to view the Big Five, and some cultural experiences like a traditional braaivleis in an open-air boma, and operating the ZS9YOTA special events station.

The theme of “Train the Trainer” will be explored, to enable participants to return to their home countries, equipped and inspired to organize and promote radio amateur activities to other youth groups, or ultimately starting a youth group.

An item of technology used for the rescue of the 13 people trapped in the cave system in Thailand came from Israel, where a company called Maxtech Networks has developed a mesh capability which allows handheld radios in a cave system to talk to each other, by being relayed to each other by a third handheld somewhere between them. Radio amateurs recognise this capability as being similar to repeaters, where our signals go in to the repeater on one frequency, and are simultaneously retransmitted out on a different frequency to the next radio in  the chain. However, with a mesh capability, the signal can be on the same frequency for the entire message path.

Uzi Hanuni, founder and CEO of Maxtech Networks was interviewed this week on CNN, and described his technology, which can daisy-chain the radio system to transmit video, voice and data as needed. Certainly good technology amongst rescue services.

And, since we’re talking about it, I’m sure you’ll join me in being hugely relieved that all 12 soccer players, and their adult coach were successfully rescued this week. It has been a very stressful time for the families of the victims. Tribute also needs to be paid to the senior diver who lost his life trying to ferry oxygen in to the trapped team. His efforts were not in vain.

In further watery disasters, the death toll from Japan’s record rainfall of last weekend stands now at 204, with another 40 people not accounted for. 6700 people are staying in evacuation shelters, nearly 5.9 million people were ordered to leave their homes in 19 prefectures due to landslides and flooding, and 203000 households are still without running water. It seems that the rain has stopped, but there is an enormous amount of clearing up and restoration of essential services still to be done. Japan’s Prime Minister Shinzo Abe cancelled his trip to Europe and the Middle East to oversee the Government response in the country.

Tropical Cyclone Maria-18 of last weekend crossed the Chinese Coast on Wednesday, and rapidly blew itself out, so that danger is over, without much damage or injury reported.

Off the Eastern American border with Canada, Hurricane Chris continued to track northeast at 37 kilometres per hour with sustained winds of 165 kilometres per hour, and was due to make landfall on the Avalon Peninsula late Thursday night as a post-tropical depression.

Rainfall in the affected area was likely to amount to 50 to 70 millimetres, with 80 to 100 kilometre per hour winds, and large surf.

A summary of rainfall figures in the provinces of South Africa shows all provinces except the Northern Cape’s averages as static or slightly up. The Northern Cape’s dams have emptied by 7 percentage points, compared to last week, now at 86% full. The Western Cape’s dams are up by 5 percentage points, to 47% full, compared to 24% full at this time last year. Our big dam, Theewaterskloof is standing at 38% full, as of yesterday afternoon, compared to 18.9% last year. Very reassuring indeed.

And snow reports in our area yesterday came from the Afriski Mountain Resort in Lesotho, and the Matroosberg, and Drakensberg mountains, as well as Sani Pass in to Lesotho. Snowreporter.co.za has plenty of pictures and videos of the snow on Saturday.

The ARRL News reports that IARU Region 1 Emergency Coordinator Greg Mossup, G0DUB, has posted a report on the Emergency Communications Meeting held at June’s Ham Radio event in Friedrichshafen, Germany. Mossup said some 20 emergency communicators attended the June 1 meeting, sponsored by the IARU.

“After the introduction and Region 1 report, there were interesting presentations followed by a good exchange of information in an open forum session, which carried on beyond the official closing time of the meeting,” Mossup said in his report.

He said Michal Wilczynski, SP9XWM, and Krzysztof Gaudnik, SP7WME, presented on emergency activities in Poland, followed by Herbert Koblmiller, OE3KJN, who discussed “Exercise Solar Flare,” which saw good cooperation between Austrian radio amateurs, the military, and service providers. Finally, Alberto Barbera, IK1YLO, and Marco, IU1GJE, spoke about the internet-linked DMR network they have been working on for use in emergencies and disasters.

HAMNET South Africa hopes you will bundle up and keep warm during this coldest period of South Africa’s Winter. With schools opening for the second semester this week, viral infections will be rife, so please be well prepared for the cold.

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.


HAMNET Report 8 July 2018

In the never-ending discussion as to the likelihood that there is intelligent life out there, a new report from Quartz says there’s a good chance that humans are the only intelligent life in the galaxy, according to a new study submitted to the journal Proceedings of the Royal Society of London. As Quartz reports, researchers at Oxford University’s Future of Humanity Institute applied existing knowledge of biology, chemistry, and cosmology to the Drake equation. This was created by astronomer Frank Drake in 1961 as an attempt to calculate the number of intelligent civilizations that could be in our galaxy. He included factors like the average rate of star formation and the average lifespan of intelligent civilizations.

They estimate there’s a 53 to 99.6 percent chance we’re alone in the galaxy, and a 39 to 85 percent chance we’re the only intelligent life to be found in the entire universe.

“Where are they?” the researchers ask, referring to the classic Fermi Paradox, which asserts that intelligent extraterrestrial beings exist and that they should have visited Earth by now. “Probably extremely far away, and quite possibly beyond the cosmological horizon and forever unreachable.”

Seth Shostak doesn’t buy it. Shostak is senior astronomer at the SETI Institute, a research organization that analyzes radio signals for signs of extraterrestrial intelligence. Part of the challenge with mathematical modelling like this, Shostak says, is that the data are limited; scientists just haven’t looked at very many star systems.

“I could walk outside here in Mountain View, California and not see too many hippos strolling the streets,” he tells Mental Floss. “But it would be incorrect for me to say on that rather limited basis that there’s probably no hippos anywhere. It’s a big conclusion to make on the basis of a local observation.”

Moreover, they may not even know what to look for in the solar systems they have reviewed. The SETI Institute examines radio communications and light signals, but there’s always the possibility that an intelligent civilization has attempted to contact us using means we may not have developed or even considered yet.

The Fermi Paradox itself may be naïve in its understanding of the universe, Shostak says. “You could have said the same thing about Antarctica in the 1700s. A lot of people wondered, ‘Is there a continent down there?’ On the one hand, you could argue there was [a continent], and on the other hand, you could say, ‘Look, there’s an awful lot of water in the Pacific and the Atlantic, and there’s no continents there, so why should there be one at the bottom of the ocean?’”

In other words, any conclusions about the existence of extraterrestrial intelligence are likely to be presumptive, made before any solid data is released or discovered. The truth may be out there, Shostak says. We just haven’t found it yet!

Now a report back about Hamvention near Dayton in May that shows the third highest attendance ever, at 28417 visitors, only 900 less than last year’s attendance, also at the new venue at Xenia. The organisers feel that there was slight reluctance on the part of rank and file amateurs to attend, because of reservations based on last year’s muddy flea market, and promised upgrades which were late in being announced.

Hamvention’s 2018 theme was “Amateur Radio…Serving the Community,” and the event highlighted emergency communication forums – many put on by ARRL – plus a big display of emergency communication vehicles. Nearly 800 volunteers put in a lot of their time before and during the convention to make it the success it was.

Last week’s Tropical Storm blew itself out alongside South Korea without doing much damage, but this week we have a new threat. Tropical Cyclone Maria-18 has been bearing down on the South coast of China, threatening to sideswipe Japan as it travels from South-East towards  North-West. On Thursday it was leaving the Guam area, and moving towards the Chinese coast, with Japan to its North and Taiwan to its South, and threatening an estimated population of 19 million people with wind-speeds of about 120km/h. Wind-speeds may reach 259 km/h, making it a category 5 storm. It’s main effect is to be expected on Monday, when it approaches the Chinese mainland.

Meanwhile, heavy rains already falling in Japan have killed at least 20 people and resulted in the ordered evacuation of 1.9 million people from threatened areas. Intense rainfall triggered huge landslides and flash floods in Hiroshima, Okayama, Kyoto and other regions, while hampering rescue operations with dozens of people reportedly missing. Some areas have been hit by more than a metre of rainfall, according to the government, while around 48,000 troops, police and firefighters have been deployed for rescue operations. We hope there Ham radio operators amongst them.

The Japan Meteorological Agency upgraded its alert system to the highest level—only issued when the amount of rain is expected to be the highest in decades—in large areas of Western Japan. Heavy rain was forecast to continue until Sunday in Western and Eastern Japan.

And the Hurricane Watch Net is having its attention drawn to early tropical depressions in the Atlantic Hurricane Basin. One such depression, entitled TD 3 at the moment, has been modelled by computers, and may grow and move up along the US East Coast into Nova Scotia, Canada.

A compact tropical cyclone, named Beryl intensified on Friday night to become the first hurricane of the season in that area. It is predicted to remain East of the Lesser Antilles until today (Sunday), and hopefully will weaken and dissipate before reaching the islands. Maximum winds so far seem to be in the 130 km/h range.

Luckily, the Western Cape Province is not having that kind of rain, but we are very happy to be able to report the City of Cape Town and surrounding dams currently at an average of 52.4% full. Our biggest dam, Theewaterskloof, is the slowest to fill, currently at 38.5% full, but there is a lot of river water still flowing in to it, and a lot of snow on the surrounding mountains still to melt and run in to all the dams, so we’re nowhere near finished with this rainy season yet. July and August’s rain has still to fall.

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.

HAMNET Report 1 July 2018

It is with sadness that we have learned that Ashley Ware-Lane’s key has become silent.

Ashley ZS1ASH was well known throughout the Western Cape Rescue Community as an operator for both ORRU and HAMNET and attended many rescues in his day. He was recently the chairman of the 4 wheel drive club and the organiser of a number of HAMNET Winter Exercises.

His bright and jovial presence will be missed by all but no more than  by his family. At this time our thoughts are with Mari, Bradley, Celine and his extended family.

Funeral arrangements will be made known later this week.

The Global Disaster Alert and Coordination System (GDACS) has been tracking Tropical Cyclone PRAPIROON-18, as it moves Northwards to hit the Southern tip of South Korea tomorrow (Monday) at 06h00 UTC, before turning North-East to skim the coast of North Korea. Maximum wind speeds are expected to reach nearly 140kph, and GDACS has set the alert level at RED.

Last Sunday, Andrew Gray ZS2G of HAMNET Eastern Cape reported that PE Amateur Radio Society members and Hamnet assisted the Mountain Club and EMS in bringing down two injured hikers on the Lady Slipper Mountain on Saturday afternoon the 23rd of June. The first injury was a suspected broken ankle. As the rescuers were making their way to the patient, another report came in that someone else higher up the mountain had fallen and sustained a head injury. The foot injury patient recovery was put on hold, while the head injury patient was brought down the mountain and flown to hospital. The second patient was off the mountain and at the ambulance by 16h15. It was really tough on the people who did two trips up the mountain. Andrew thanks and greets all who assisted, and says “Well done”!

In a sad ending to another rescue, HAMNET Western Cape participated in the eventual retrieval of a Cape Town Psychologist’s body, which was brought down off Table Mountain after a prolonged search. David ZS1DAV was duty logistics manager at the time.

A report coming from John ZS1JNT and Bruce ZD7VC brings to an end a saga that began in October 2015, when an unusually designed 51 foot high performance catamaran sailing yacht coming down the coast off the Eastern Cape struck a whale and started to take on water. After putting out a Mayday call on the Marine VHF radio, the owner/captain and his crewman abandoned ship in a dinghy and triggered their EPIRB. Shipping in the area was coordinated to search for the sailors and the capsized yacht was soon found, but it took another 24 hours to find the crewmen in their dinghy. They were finally rescued in 50 knot winds, and brought to Cape Town.

Nearly three years later, the Sea Rescue Service of St Helena found a piece of boat wreckage washed up on an inaccessible rocky beach of the island, called Turks Cap Bay. Sea Rescue decided to ask Bruce ZD7VC to help them identify the wreckage. Bruce thought of his old sailor friend John ZS1JNT, in Cape Town, and emailed him the details and pictures of the wreckage. John  identified them as bits of the bridge-deck of a catamaran, but with an unusual design and construction. There were features unusual in a catamaran, so John sent pictures to a few yacht designers around the world, who identified the structures as being of French origin.

A week ago, a knowledgeable cruiser in the United States thought the bridge construction looked similar to a yacht type called a “Switch 51”. It was discovered that only about a dozen of these had been built, and only one ever abandoned – the yacht struck off the East Cape Coast in 2015.

And thus, through the spirit of ham cooperation, was a mystery solved. The drift pattern to take the vessel Southwest in the Agulhas current and then up the West coast of Africa in the Benguela current, all the way to the tiny island of St Helena, is quite remarkable – a passage of around 2500 nautical miles or 4600 kilometres in just over two years and 7 months.

Thank you, John for this interesting story, and congratulations to you and Bruce on the ferreting achievement.

The ARRL letter for 28 June reports that, with typical propagation no better than fair to pretty good, most ARRL Field Day participants nonetheless enjoyed the 2018 running of Amateur Radio’s most popular operating event — most as part of club or group operations and some as individuals. Among them was an ARRL Headquarters team that included several newer operators as well as some veterans, who operated Maxim Memorial Station W1AW. ARRL Station Manager Joe Carcia, NJ1Q, said most contacts at their station were on the HF bands, with a handful of VHF/UHF FM and SSB satellite contacts via SO-50 or FO-29.

“Conditions were so-so on 15 and 10, but 6 meters opened for a while, and 20 and below were hopping!” Carcia enthused.

More than 1,600 clubs and groups registered their locations on the ARRL Field Day Locator website.

The newsletter includes reports from stations in the mountains, others out on rivers, some working low power (QRP – less than 5 watts output power), some operating CW only (morse code), and others only digital modes.

The station reports continue to come in, and we will try to bring the interesting ones to you.

Finally, I am happy to bring you news of record rains in the Western Cape for the month of June. Dam levels are on average very close to 45% full, much better than this time last year or the previous year, and, at my station, a record amount of 145mm rain has been measured, better than all June rainfall in the last 18 years, which is how long I have been keeping records. Long may this Winter trend continue!

This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.