Stalagmite study offers clues about Earths past magnetic polarity shifts

first_img The geomagnetic field shields Earth from the direct impact of solar wind and cosmic radiation. Credit: PNAS © 2018 Phys.org 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. Stalagmites in southern China preserve detailed geomagnetic oscillations and centennial geomagnetic reversal events. Credit: PNAS Journal information: Proceedings of the National Academy of Sciences A large team of researchers from China, Taiwan and Australia has found evidence of faster-than-expected shifts in Earth’s magnetic polarity several thousand years ago. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of stalagmites found in a cave in China and what they found. More information: * Yu-Min Chou et al. Multidecadally resolved polarity oscillations during a geomagnetic excursion, Proceedings of the National Academy of Sciences (2018). DOI: 10.1073/pnas.1720404115AbstractPolarity reversals of the geomagnetic field have occurred through billions of years of Earth history and were first revealed in the early 20th century. Almost a century later, details of transitional field behavior during geomagnetic reversals and excursions remain poorly known. Here, we present a multidecadally resolved geomagnetic excursion record from a radioisotopically dated Chinese stalagmite at 107–91 thousand years before present with age precision of several decades. The duration of geomagnetic directional oscillations ranged from several centuries at 106–103 thousand years before present to millennia at 98–92 thousand years before present, with one abrupt reversal transition occurring in one to two centuries when the field was weakest. These features indicate prolonged geodynamo instability. Repeated asymmetrical interhemispheric polarity drifts associated with weak dipole fields likely originated in Earth’s deep interior. If such rapid polarity changes occurred in future, they could severely affect satellites and human society.* Press release Explore further Earth’s magnetic field is not about to reverse, study finds Citation: Stalagmite study offers clues about Earth’s past magnetic polarity shifts (2018, August 21) retrieved 18 August 2019 from https://phys.org/news/2018-08-stalagmite-clues-earth-magnetic-polarity.html Prior research has shown that the Earth’s magnetic field sometimes reverses polarity—such an event has been experienced only once by modern humans, but that was long before the age of satellites and electronics. In the modern age, such a reversal could spell trouble for many devices that we have come to rely on. For that reason, scientists study past reversals in the hope of predicting when the next might occur. In this new effort, the researchers traveled to the Sanxing Cave in Guizhou Province in southern China. There, they obtained samples of stalagmites (columns of calcium salts that rise from the floor of caves, caused by dripping water), which hold evidence of changes to the magnetic field going back thousands of years.The Earth’s magnetic field is generated by liquid metal churning at depths 1,700 miles below the surface. But sometimes, that churning can change slightly, affecting the magnetic field. Prior research has suggested that a full reversal would likely take thousands of years, but this new research suggests it can happen in as few as 100.The researchers report that the stalagmite sample taken from the cave showed evidence of magnetic field changes from 107,000 to 91,000 years ago—a span of 16,000 years. By studying the sample very precisely using a high-resolution cryogenic magnetometer, the researchers were able to trace changes in the magnetic field more precisely than has ever been done before. In so doing, they discovered that approximately 98,000 years ago, a magnetic reversal occurred over just a century and a half, approximately 10 times faster than had been believed possible. The researchers found several other phase changes, as well, with various degrees of fluctuation strength. They also found that when the magnetic field was weaker than normal, more fluctuations in strength occurred. They suggest such fluctuations likely caused some instability in convection in the planet’s outer core.last_img read more

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From Fruit Fly To Stink Eye Searching For Angers Animal Roots

first_img“Practically every sexually reproducing, multicellular animal shows aggressive behavior,” says David Anderson, a professor of biology at Caltech and co-author of the book The Neuroscience of Emotion.”Fruit flies show aggression.” For comedian Lewis Black, anger is a job. When I relay that last bit to Black, he’s skeptical. “Really?” he says. “Come on.” Onstage, he often looks ready for a fight. He leans forward. He shouts. He stabs the air with an index finger, or a middle finger. There’s an ongoing debate among scientists about whether that’s true. Psychologist Lisa Feldman Barrett of Northeastern University is among the researchers who contend that human emotions including anger are “constructed” rather than hard-wired in the brain. Read the whole story: NPRcenter_img Black is famous for his rants about stuff he finds annoying or unfair or just plain infuriating. — To a scientist, Black looks a lot like a belligerent dog, or an irritated gerbil.last_img read more

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The colours of winter

first_imgThe art show titled The Winter Tale is driven with the intention of displaying works by an array of renowned artists.The amalgamated and showcased art by many renowned artists under one roof affirms aesthetic sensibility and celebrates the creative impulse that weaves colour and form into variegated manifestations of visual reality. Each of the works is selected after serious deliberation on the individual profile and work corpus of the respective young artist. Also Read – ‘Playing Jojo was emotionally exhausting’Colorful abstracts executed in vibrant colours by artist Gurdeep Singh emanates energy through the bold strokes and thick impasto technique. These art works takes you beyond the limitation of perceived physical ideas, forms and realities. Manu Parekh’s The temple boat at the Banaras Ghats, scenery is expressed through prominent lines and forms which display a volatile energy that can barely be contained within the confined structural space.Revati Sharma Singh’s works shows the metamorphosis in thought process as an endless experience of life depicted in an amalgamation of her thoughts. The visual imagery of striking colours, bold strokes and the play of textures are stunning. Artist Shuvaprasana has an interesting mix of tradition and contemporaneous character in the all the works that includes portraiture, paintings, charcoals, drawings, etchings and sculptures. Thota Vaikuntam’s works as always are close observation of the rural life is expressed through the detailed portraits of the Telangana people. Vaikuntam mainly prefers the primary colours and pure Indian hues like- reds and yellows. His beloved Telangana is beautifully portrayed through his paintings.When: Till 31 January 2014Where: Gallerie Nvya, saketlast_img read more

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Tagore returns to Delhi

first_imgPopular children’s stories of Rabindranath Tagore like Kabuliwala among others will be staged during a five-day children’s theatre festival in the national capital beginning 18 June, the organisers said Tuesday.Presented by Hindi Academy, the inaugural ‘Bal Utsav’ will showcase ten famous stories written by the Nobel laureate. Two plays will be staged per day at the Kamani Auditorium. The theme of this year’s festival is ‘This Summer Children are in Tagore’s Company’. Also Read – ‘Playing Jojo was emotionally exhausting’The academy had organised a month-long workshop across various schools in Delhi to choose children to play various roles in these plays.‘From these workshops around 450 students have been selected,’ an official from the Hindi Academy said. ‘In the workshop, directors and assistants trained these children. These stories were first translated from Bengali to Hindi and children started rehearsing,’ he added. The festival will open with Rajesh Bakshi’s Ichchha Puran, followed by Asif Kamar’s Chhutti.On the second day Nilesh Kumar Deepak’s Kabuliwala and Anumita Dutta Choudary’s Taash Ka Desh will be staged.Other stories like Doctor Babu aur Mukut, Tota Kahani, Subha, Bhikarin, among others will be staged.When: 18June onwards Where: Kamani Auditoriumlast_img read more

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Drug awareness

first_imgJune 26 is the International Day against Drug Abuse.  Every year since 2003, the mass awareness event Run against Drug Abuse is being held at India Gate on this day. A joint venture of 13 partners in the 13th year of this mega event, aims to spread the message — Think Health Not Drugs. This year the event focussed on the message — Drug use disorders are Preventable and Curable. Cabinet Minister Thaawarchand Gehlot (Ministry of Social Justice & Empowerment, GOI) and Sandeep Kumar, Minister , Social Welfare/Women & Child Development, Govt. of Delhi, flagged off the Run and  took  pledge with other dignitaries and 4000 participants  Also Read – ‘Playing Jojo was emotionally exhausting’present at the occasion.The event also featured a number of activities such as ­— thematic cultural show with skits, demos to spread awareness on drug use prevention, slogan March, yoga, martial art — self defense, poster competition, dance, counseling and expo on Drug de-addiction.Participants from various government Institutions, Schools and colleges, NGO’s, Defense/Police forces (CRPF, BSF, ITBP, Indian Coast Guard, SSB, CISF), NCC cadets, scouts, Civil Defense, Martial art academies, media along with the members of civil society organisations took part in the Run.last_img read more

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Misti Hub launches Facebook page folk artists to perform regularly

first_imgKolkata: In a bid to popularise Bengal’s mouth watering sweets among people, the Facebook page for Misti Hub, situated in New Town, was launched on Saturday afternoon.The hub will act a platform for the budding folk artists, who will perform at the hub regularly. This platform was inaugurated on Saturday with a musical performance by well-known folk artist Saurabh Mani.For the first time in Bengal, 10 famous branded sweet shops of Kolkata have opened their outlets under one roof. The hub has come up near gate number 3 of Eco-Park off Biswa Bangla Sarani. The hub is open from 12 noon to 9 pm. Now, people can leave comments and reviews about the sweets on the Facebook page. One will also get to know about the new varieties that are being introduced and the musical programmes to be held from the page. The main idea behind the hub is to explore the tremendous potential of Bengali sweets both in the country and abroad.Earlier, people from abroad and other states, who wanted to take Bengal’s special sweets along, could not find the shops as they are situated in different parts of the city. But now they can. The Misti hub offers both traditional and modern sweets.last_img read more

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Six killed including minors in accident

first_imgKolkata: Six persons including two children died in a tragic road accident at Mathabhanga in Cooch Behar district on Monday late night.Four people died on the spot when a vehicle hit a truck standing on the Siliguri- Mathabhanga Highway at around 2.15 am. The impact of the collision was such that the vehicle fell into a canal on the side of the road. Several persons were also injured in the accident. According to police sources, the deceased has been identified as Khagen Rabha (35), Ajoy Sonar 32, Ratna Munda 45, and Payro Munda 40 and Sonamoni Munda (2). The identity of another child has not been ascertained as yet. Also Read – Rain batters Kolkata, cripples normal lifeImmediately after the accident, locals of Bhomramguri village along with the officials of Mathabhanga police station rushed to the spot and took the injured persons to Mathbhanga Mahakuma hospital. Four were declared brought dead, while two children died in the hospital.The injured persons include — Budhuya Khariya, Bandheni Munda, Somra Munda, Biraj Munda, Mona Munda and Gita Munda to name a few. All of them were travelling from Tufangunj in Cooch Behar and Samuktala from Alipurduar to work at a brick kiln at Bihar’s Purnea. After rescuing the passengers, police along with the disaster management team also lifted the mangled vehicle and took it to the police station. Cops have started an enquiry into the cause of accident though preliminary investigation has revealed that the driver has fallen asleep while driving.last_img read more

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Style hacks for all dads

first_imgA solid white or navy poplin shirt or smaller tartan with country checks tucked in with a pair of slim fit, stretchable jeans and aviators will keep you in vogue irrespective of your age, say experts. Take a look at the below mentioned style hacks:Linen shirts: A crisp linen shirt is an absolute must-have in any father’s wardrobe. A millennial father would look dapper in a full-sleeved linen shirt with rolled-up sleeves paired with denim jeans. For a seasoned father, a short-sleeved linen shirt tucked in with clean and clear cut creases would be more appropriate to give him a prim and proper look. Also Read – Add new books to your shelfPolos: Polos are extremely versatile. It is recommended, especially for seniors, that they experiment with polos for a fresher optic. They could try saturated brights paired with navy chinos or rugby polos for a family day out and printed polos for an evening get-together. The new age dads could opt for solid polos with denims or chinos.Prints: Younger dads could opt for subtle, minimal, tonal prints while the senior ones could try printed shirts with khakis, geometric motifs/cravats. Also Read – Over 2 hours screen time daily will make your kids impulsiveBelts: The most essential accessory in any man’s wardrobe is the belt. The choice of belts is very important. It’s time to give up on the conventionally formal metal buckle belt and instead move towards matt finish leather belts.Denims: The younger dad could go for denims with a medium to heavy wash accompanied by mild distress along with plaid. The older ones should opt for cleaner, mid-washed to rinsed jeans that could be clubbed with a solid shirt, tan belt and leather boots. Khakis: From its origin to its sturdiness, khaki beautifully blends into the Indian man’s wardrobe. Be it the khaki-based checks or brown tartans, they go well with Indian geography. The younger dads could go for earthy shades, be it mud-brown or maroon with bigger checks paired with desert boots. The seniors could bring alive the perfect urban escape by adding a dimension of adventure amidst wilderness.Invest: Divulge in live-forever pieces like a good white oxford shirt, premium indigo denim, leather bomber, cable knit sweater, pure wool suit and a navy blazer.last_img read more

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Bengal MPs to heighten glam factor in LS

first_imgKolkata: Bengal is set to raise the glam quotient in the upcoming Lok Sabha with a number of celebrity candidates sailing through the bitterly fought elections in the eastern state. Making their debut in the lower house of Parliament are two young Bengali actresses and Trinamool Congress winners — Nusrat Jahan (Basirhat) and Mimi Chakraborty (Jadavpur) — both famed for their oomph factor. Trinamool chief Mamata Banerjee’s decision to nominate the two political greenhorns had created quite a sensation, and they even became the butt of distasteful trolls on the social media. When the TMC announced its decision, there was a flurry of memes, jokes and comments. There were reports that several netizens were disgruntled with the development and quoted someone saying that Mamata Banerjee should know that unlike the Indian Premier League, politics does not need cheerleaders. However, the counting of votes has proved otherwise and shown that Tollywood celebrities can not only make the audiences flock to the theatres, but can also get a sweeping victory on the political battlefield. Also Read – Rs 13,000 crore investment to provide 2 lakh jobs: MamataBanerjee’s gamble paid off as both actors defeated their BJP rivals by handsome margins. Chakraborty triumphed by a margin of 2,95,239 votes over Anupam Hazra, while Jahan left her nearest rival Sayantan Basu behind by 3,50,369 votes. Bollywood singer-actor-turned-politician Union minister Babul Supriyo retained his Asansol seat, but his victory robbed Parliament of the presence of yesteryear actress Moon Moon Sen, who lost out in the race. Bengali superstar Deepak Adhikari (Dev) retained the Ghatal seat for Trinamool, humbling BJP nominee and former IPS officer Bharati Ghosh. Deb’s winning margin was 1,07,973 votes. Also Read – Lightning kills 8, injures 16 in stateAll the hard work of BJP’s Locket Chatterjee, who had failed to turn the tables on her opponents during the 2016 Assembly elections, brought cheer to the party as she won the Hooghly seat defeating Trinamool’s sitting MP Ratna De Nag by 73,362 votes. Another yesteryear actress and the Trinamool’s Birbhum candidate, Shatabdi Roy, posted a hat-trick of Lok Sabha wins by getting the better of BJP’s Dudh Kumar Mondal by 88,924 votes. However, theatre personality and Trinamool’s Lok Sabha sitting member Arpita Ghosh fell by the wayside in Balurghat, from where her BJP opponent Sukanta Majumdar won with a 33,293-vote margin.last_img read more

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Tips for studying abroad

first_imgAmong the more important things we do in life is to take decisions. At a time of information overload, this can be particularly challenging. And yet, this is the time of year when students have to make up their minds on their future course of study. It is one of the most difficult and important decisions they would need to take and would, most certainly, impact them for the rest of their lives. Trends suggest that there would be an increasing number of Indian students who would be opting for higher studies, particularly in Australia. Also Read – Add new books to your shelf What are some of the key things to keep in mind? Do your homework, but don’t get bogged down: Doing your homework and basic research are important, but too much information can make decision-making difficult and even confusing. It is important to decide what subject you would like to pursue, where you would like to study, whether you meet the entry and eligibility criteria and, finally, do you have the required funds to pay for it. Given the Indian Rupee-Australian Dollar exchange rate, studying in Australia is significantly cheaper than opting for the US and the UK, which pose additional and new challenges. Also Read – Over 2 hours screen time daily will make your kids impulsiveKnow how to apply: If you are going through an education agent, first find out which education agents have been empanelled by the university of choice. For instance, the internationally-ranked University of New South Wales (UNSW), Sydney, has only 12 registered India-based education partners. No one else is authorised to process student applications. The list is available on the university’s website. Furthermore, empanelled agents are not authorised to charge students for services they render. Such payments, or commissions, are paid by the university. Know why you are pursuing higher studies: Simon Sinek, in his path-breaking book, ‘The Power of Why’, emphasised the misplaced emphasis that so many place on “what” and “how” without ever knowing “why”. If we know “why” we are planning on a particular course of action, other things fall in place. In terms of sequencing, “why” is where we first start. You can decide, for instance, to pursue an undergraduate course in Finance and Accounting if you are clear in your mind as to why you would like to do so. Once you know your “why”, the “where” is easy. Embrace Change: Often our parents, in particular, and sometimes even we, fear the uncertain. Living abroad, especially if it is the first time, can be challenging. Is it safe? What is the culture like? Would my son or daughter make friends? Would the studying and living culture cause problems? These are all legitimate questions and anxieties. At the same time, if the decision is to study abroad, it is important to be open to change. Some things might be similar to what we are used to but there would be big differences in several other aspects. What is particularly fascinating is that “other cultures” open up the mind to new ways of seeing and thinking – and even behaving. Learn with Passion: We can learn every single day but only if we are open to it. “Smell the roses” we are told and yet, we rarely do. Employability is not a quotient of how many books we have read or quotations we know by heart but how we are able to relate with our external environment. This is what employers look for because what they want are persons who can work in a team, who can take decisions and, consequently, who anticipate and solve problems without compromising on integrity and values. Great educational institutions recognise this and embed it into their pedagogy. It is what makes them stand out.last_img read more

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