Chelsea will assess Ramires ahead of the derby with Fulham.The midfielder missed Saturday’s 2-1 win against Wigan because of illness but it is hoped that he will be available for the Easter Monday clash at Craven Cottage.John Terry, Frank Lampard and Ashley Cole, who all missed the Wigan game, will also be checked to see if they can rejoin the Blues squad.Skipper Terry is nursing a rib injury, while Lampard has a thigh problem and Cole recently suffered a twisted ankle.See also:Last-ditch Mata gives Chelsea victoryChelsea showed their strength, insists bossFollow West London Sport on TwitterFind us on Facebook
Ostrich eggshell beads from Border Cave, which show similar production techniques as those used by Kalahari San women. People used beads as part of a gift exchange system, just as modern people give and receive presents from each other. A Kalahari San woman drilling through beads to produce perforations. Prof Francesco d’Errico, leader of the international research team. The site is a treasure trove for archaeologists as it records well preserved organic remains from that time. (Images: Lucinda Backwell) Notched bones were used for counting purposes and the stone tools discovered in the same archaeological layers show a gradual evolution in stone tool technology. (Image: Francesco d’Errico and Lucinda Backwell) MEDIA CONTACTS • Erna van Wyk Communications Officer Wits University +27 11 717 4023 RELATED ARTICLES • Fossils tell the mammal story • No bedbugs for early humans • Maropeng top evotourism destination • Khoisan couple home at last Wilma den HartighRecent analysis and dating of archaeological material discovered at a rock shelter in South Africa reveals that modern human behaviour, as we know it, developed much earlier than previously thought.The findings of a multi-disciplinary research team made up of scientists from all over the world has shed new light on this topic, providing answers to the crucial question of when in prehistory human cultures similar to ours emerged – something that human evolution scientists have grappled with for many years.Dr Lucinda Backwell, a senior researcher in palaeoanthropology at Wits University says until now, many archaeologists believed the oldest traces of San hunter-gatherer people in South Africa dated back 10 000 to 20 000 years, at the most.However, when researchers analysed objects retrieved from archaeological layers at KwaZulu-Natal’s Border Cave, they discovered people lived at this site as far bar back as 44 000 years ago.“This find is important because it shows the earliest evidence of modern human behaviour as we know it,” Backwell explains.“What we found there shows that people made use of symbolism, they were innovative and had cognitive ability.“It reveals that we are more like than we think we are.”More alike to our ancestorsProf Francesco d’Errico, leader of the international team and director of research at the French National Research Centre, says their results confirm that when people in southern Africa developed a lifestyle similar to that of hunter-gatherers, it remained almost unchanged for 40 000 years.He believes this adds a new dimension to the definition of modern cultural adaptation.“We often consider modern behaviour as synonymous with rapid cultural turn over,” D’Errico says.“The results show that even among modern humans, as among previous human species, culture can remain almost unchanged for very long, when there is no need to change.”What they foundThe site is a treasure trove for archaeologists as it records well preserved organic remains from that time. By using radio carbon methods, microscopic and chemical analysis, the team was able to identify how the artefacts were manufactured, used and what they were made of.“We were able to show in this way that already 44 000 years ago the inhabitants of this site manufactured and used many artefacts that until recently were an integral part of Kalahari Bushman culture,” Backwell says.Many of the discoveries, such as the ostrich egg and marine shell beads used as jewellery, show that even 44 000 years ago early humans had great aesthetic sense.“This shows that the first focus of aesthetic behaviour was the human body,” D’Errico explains.Backwell adds that people also used beads as part of a gift exchange system, just as modern people give and receive presents from each other.“It is similar to bartering, but this system was reciprocal and not just a business transaction,” she says.They also used notched bones for counting purposes and the stone tools discovered in the same archaeological layers show a gradual evolution in stone tool technology.“They fashioned fine bone points for use as awls (long pointed spikes) and poisoned arrowheads,” Backwell says. “One point is decorated with a spiral groove filled with red powder, comparable with similar marks made by Bushmen to identify their arrow heads when hunting.”Complicated chemical analysisUsing only a grain of material smaller than a pinhead, chemists based in Italy made extraordinary discoveries about the use of natural materials to manufacture poison and glue.A closer look at the artefacts revealed the earliest evidence for the use of poison. Chemical analysis of residues on a wooden stick decorated with incisions shows it was used to hold and carry a poison containing ricinoleic acid found in castor beans.The oldest known use of beeswax as an ingredient in glue was also discovered at the cave. Backwell says the lump of beeswax, mixed with the resin of Euphorbia (a plant with poisonous milky sap), and possibly egg, was wrapped in plant fibres made from the inner bark of a woody plant.The beeswax product was used as a binding agent to make stone tools such as arrowheads using a hafting technique, a process which involves attaching bone, metal or stone to a handle or shaft. Through this process, early humans could make tools that were more useful and stronger, such as a spear or an axe.“This is a complicated list of ingredients used to make tools with impact,” she explains.Once the arrowhead was attached using the binding agent, it was reinforced with twine or animal ligaments.The inhabitants of the cave also shaped warthog tusks into awls and possibly spear heads. “The use of small pieces of stone to arm hunting weapons is confirmed by the discovery of resin residue still adhering to some of the tools,” she says.The Italian chemists identified the resin to be suberin, a waxy substance produced from the sap of yellowwood trees, also used in the hafting process.She says the variety of ingredients indicate the ability of early human cultures to adapt to their geographical surroundings and use any available materials.More questionsBackwell says there are still many unanswered questions, such as why there appears to be a different rate of cultural development of early humans.“There are clear signs of a punctuated evolution,” she says.There are many theories as to why this happened, ranging from communities moving to another site, population growth, or even a loss of interest in a particular innovation.“Innovations came, were used and were lost again. This shows that human evolution was not entirely gradual,” she says. “There is also a possibility that entire communities could have been wiped out by illness or disease.”According to D’Errico, their research further demonstrates that Bushmen technology and lifestyle emerged abruptly, and remained relatively unchanged until recent times.“This represented an extremely successful and flexible cultural adaptation, able to cope with changing African environments,” he says.He believes their results have implications for the origins of language and the relationship between genetic and cultural heritage.Backwell anticipates that more archaeological material will be discovered at Border Cave. “At the same cave, the oldest child burial site was discovered, dated 80 000 years ago,” she says.She explains that the excavation, analysis and interpretation of the artefacts found at Border Cave demonstrate the value of interdisciplinary collaboration.She’s also consulted with Kalahari Bushmen in the Botswana and Namibia regions. “”They have shed new perspectives of what we’ve found,” she says.
Former Australian skipper Ricky Ponting has analysed that the shoulder injury to KL Rahul has played an underappreciated role in Royal Challengers Bangalore’s (RCB) horror campaign in the ongoing tenth edition of the Indian Premier League (IPL).Predicting how RCB have gone from 2016 finalists to 2017 cellar-dwellers in the IPL, Ponting said although poor form of key players like Virat Kohli, AB de Villiers and Chris Gayle can be the obvious reason behind the team’s downfall, he insisted that the absence of Rahul could not be avoided.The 42-year-old, who was in charge of Mumbai Indians in 2015-16, pointed out that Rahul and Kohli were a pretty formidable opening pair last year and, therefore, the absence of one of them is a massive loss for the RCB.”KL Rahul is a massive loss for them. He had a terrific back-end to last season. He did some amazing things last year, so him not being at the top has been a big loss,” cricket.com.au quoted Ponting as saying.”He and Virat were a pretty formidable opening pair last year. You couldn’t argue with what they did last year and they’ve played a bit of cricket with each other in the Indian Test team for the few months leading in to the IPL. So they would have had a good dynamic there at the top of the order and unfortunately that’s been missing for them,” he added.Rahul, who averaged 44 in last year’s IPL, was ruled out of the ongoing IPL season as well as from the Champions Trophy after sustaining the shoulder injury during the four-match Test series against Australia in March.advertisementThe right-handed batsman opened the batting in six matches for the RCB last season, having scored more than 35 on four occasions, behind also impressing batting at No.4 spot when West Indies swashbuckling batsman Gayle returned to the side to open.ALSO WATCH:
The event will begin at 9:00 a.m. on each day and will assist the unemployed youth in Cumberland and surrounding areas to secure employment. The Social Development Commission (SDC) will be hosting its inaugural Youth Empowerment and Job Fair at the Cumberland Community Centre in Portmore, St. Catherine, from February 20 to 22.The event will begin at 9:00 a.m. on each day and will assist the unemployed youth in Cumberland and surrounding areas to secure employment.Participants will be engaged in the areas of résumé writing, skills development, leadership training, career counselling and interview preparation.Young persons between the ages of 17 and 35 are encouraged to take their résumes and meet with prospective employers from various sectors, including communications, security and business process outsourcing (BPO). Participants will be engaged in the areas of résumé writing, skills development, leadership training, career counselling and interview preparation. Story Highlights Entrepreneurship Officer with the HEART Trust/NTA, Michelle McLymonth addresses participants of a recent Social Development Commission (SDC) Fair in Annotto Bay, on workplace etiquette. The Social Development Commission (SDC) will be hosting its inaugural Youth Empowerment and Job Fair at the Cumberland Community Centre in Portmore, St. Catherine, from February 20 to 22.
Now playing: Watch this: 5:30 Internet Services Music MySpace may have lost 12 years of music in a “server migration project.” Lionel Bonaventure / AFP/Getty Images MySpace may have lost your digital memories in a server migration.”As a result of a server migration project, any photos, videos, and audio files you uploaded more than three years ago may no longer be available on or from Myspace,” it said in a note at the top of the site.”We apologize for the inconvenience. If you would like more information, please contact our Data Protection Officer at DPO@myspace.com.” Tags 5 Comments Share your voice Andy Baio, one of the people behind Kickstarter, tweeted that it could mean millions of songs uploaded between the site’s Aug. 1, 2003 launch and 2015 are gone for good.”Myspace accidentally lost all the music uploaded from its first 12 years in a server migration, losing over 50 million songs from 14 million artists,” he wrote Sunday.”I’m deeply skeptical this was an accident. Flagrant incompetence may be bad PR, but it still sounds better than ‘we can’t be bothered with the effort and cost of migrating and hosting 50 million old MP3s,’ ” Baio noted.MySpace didn’t immediately respond to a request for further comment.It might seem like a dim and distant memory now, but MySpace was an essential springboard for musicians like Arctic Monkeys in 2005 and the most popular site in the US in 2006. It was got a makeover back in 2013, when it was refurbished and rebranded as a cool place to share music and video.First published at 5:07 a.m. PT.Updated at 9:44 a.m. PT: Adds background detail. MySpace is still alive but it’s nothing like it was 15…
The researchers, Can Onur Avci et al., at MIT and ETH Zürich, have published a paper on the new memory concept in a recent issue of Applied Physics Letters.”With some device and structural optimization, the bit density of existing random access memory devices may be increased by several factors, with the possibility of all-electrical operation,” Avci told Phys.org.Magnetoresistance effects date back to around 1850, when Lord Kelvin demonstrated that applying a magnetic field to a metal object increases the object’s electric resistance in one direction and decreases it in the perpendicular direction. Since then, several other types of magnetoresistance have been discovered. Most notably, Albert Fert and Peter Grünberg won the 2007 Nobel Prize in Physics for their discovery of giant magnetoresistance, which is used to make magnetic field sensors that are found in many of the hard disk drives in today’s computers.In 2015, scientists discovered the newest magnetoresistance effect, called unidirectional spin Hall magnetoresistance. This effect differs from other kinds of magnetoresistance in that the change in resistance depends on the direction of either the magnetization or the electric current. As the scientists explain, this direction-dependent effect occurs because the spin-polarized electrons created by the spin Hall effect in a nonmagnetic layer are deflected in opposite directions by the magnetization of the adjacent magnetic layer. Previously, this new effect was demonstrated in two-layer structures consisting of a nonmagnetic and a magnetic layer. But by adding another magnetic layer, the researchers achieved a great potential advantage for memories: the ability to distinguish between not just two, but four magnetic states. Other types of magnetoresistance effects are only sensitive to the relative orientation of the magnetizations (parallel or antiparallel), although it’s possible to have four distinct magnetic states. Because the new effect is sensitive to the magnetization direction of individual layers, it can distinguish between all four states.The researchers then demonstrated four distinct resistance levels corresponding to the four different magnetic states in their three-layer device. They showed that the four resistance levels can be read out by a simple electric measurement, paving the way for the development of an all-electrical multi-bit-per-cell memory device.The researchers expect that it will be possible to scale up this memory device to higher bit densities by adding more layers, which could realistically enable eight different magnetization states, each with its own unique resistance level. In the future, the researchers also plan to look for materials that exhibit a larger unidirectional spin Hall magnetoresistance effect, which would further enhance the performance of these memory devices. (Left) With a single ferromagnetic layer, the system has two resistance levels. (Right) Adding another ferromagnet to the system creates four levels of resistance, corresponding to the four different magnetic states indicated by the arrows. Credit: Avci et al. ©2017 American Institute of Physics (Phys.org)—In 2015, scientists discovered a new magnetoresistance effect—that is, a new way in which magnetization affects a material’s electric resistance—but hadn’t yet found a promising application for the discovery, beyond the existing technologies. Now in a new paper, the same researchers have demonstrated that the effect can be used to design memories with four distinct stable magnetic states, allowing the memories to store four bits of information in a single magnetic structure. More information: Can Onur Avci et al. “A multi-state memory device based on the unidirectional spin Hall magnetoresistance.” Applied Physics Letters. DOI: 10.1063/1.4983784ABSTRACTWe report on a memory device concept based on the recently discovered unidirectional spin Hall magnetoresistance (USMR), which can store multiple bits of information in a single ferromagnetic heterostructure. We show that the USMR with possible contribution of Joule heating-driven magnetothermal effects in ferromagnet/normal metal/ferromagnet (FM/NM/FM) trilayers gives rise to four different 2nd harmonic resistance levels corresponding to four magnetization states (⇉⇉, ⇄⇄, ⇆⇆, ⇇⇇) in which the system can be found. Combined with the possibility of controlling the individual FMs by spin-orbit torques, we propose that it is possible to build an all-electrical lateral two-terminal multi-bit-per-cell memory device. © 2017 Phys.org Smart multi-layered magnetic material acts as an electric switch Journal information: Applied Physics Letters Citation: New magnetoresistance effect leads to four-state memory device (2017, June 5) retrieved 18 August 2019 from https://phys.org/news/2017-06-magnetoresistance-effect-four-state-memory-device.html Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Tuesday, November 29, 2016 Posted by Michael Smith TORONTO — In celebration of Giving Tuesday today, Intrepid Travel is donating 10% of all tour bookings to help aid four community projects around the world. Running through Dec. 20, the campaign applies to bookings on over 1,000 of the company’s small-group tours.According to the company, this is the first time it has taken this type of philanthropic approach to discounting, a concept that aligns with the brand’s mission to help consumers see the world through “real, immersive experiences while leaving the destinations they visit in a better position than it was found.”The four projects are currently supported through Intrepid Group’s not-for-profit, ‘The Intrepid Foundation’, and represent a mix of initiatives that the foundation supports through over 50 projects around the world.The projects that will benefit from the campaign include: Kusimayo (Peru), which works to improve the living conditions of children and adults affected by poverty in Puno; Blue Dragon (Vietnam), which provides vocational training and educational support to the impoverished; Pollinate Energy (India), a social enterprise that provides access to sustainable and affordable energy for India’s urban poor; and Friends of the Asian Elephant (Thailand), the FAE hospital that helps rehabilitate elephants once used in tourism entertainment venues.“The holiday season is a time of reflection and giving back,” said Leigh Barnes, North America Director for Intrepid Travel. “While we remain committed to supporting local communities throughout the year, this campaign allows our travellers to help create meaningful impact in the destinations we visit.”Globally recognized as a leader in responsible travel, Intrepid has been carbon-neutral since 2010 and has donated over $5 million through its foundation since 2002. Intrepid Travel hopes to donate $150,000 through the Travel for Good campaign, making it the largest fundraising initiative for The Intrepid Foundation in North America.Canadian agents can experience an Intrepid tour first-hand and win a spot on an upcoming fam. To find out more details, watch Travelweek’s latest video with Leigh Barnes.For more information on Intrepid Travel and the Travel for Good campaign, please visit: intrepidtravel.com/us/travel-for-good. Tags: Intrepid Travel Intrepid to donate 10% of bookings, launches agent fam contest Share << Previous PostNext Post >>