sábado, 1 de agosto de 2015
Research explores future energy security of China
| July 30, 2015 China needs to reduce its dependence on coal and improve the range of fuels it uses if it is to have long term energy security, according to new research from the University of East Anglia (UEA). The study, published in the journal Technological Forecasting and Social Change, looks at the future of electricity supply in China and the issues it faces in reducing its carbon emissions -- nationally China's electricity sector accounts for more than half its total greenhouse gas emissions. The country's electricity sector is the largest in the world and energy security concerns mean that China meets its electricity needs with domestic resources, resulting in a system heavily reliant on coal. However, increasing demand for electricity and direct coal consumption, and gradual depletion of its own supply, have led to it becoming the world's largest coal importer. Lead researcher Dr Konstantinos Chalvatzis, of UEA's Norwich Business School and the Tyndall Centre for Climate Change Research, said: "China's energy sector is under pressure to achieve a secure and affordable supply while at the same time reducing its carbon emissions. There has been this long argument about whether China can give up coal because that would harm their supply security. "We recommend that the Chinese Government continues to work towards two main objectives. First, increase the share of renewable energy sources, such as wind and hydro-power, in the fuel mix and as a result maintain high energy independence. Secondly, improve diversity in the fuel mix. If imports are necessary, prioritise non-coal fuels, such as nuclear fuels and natural gas. These two objectives will improve electricity supply security while allowing China to decarbonise its economy." While acknowledging that China appears to be leading its electricity sector away from the dominance of coal, the researchers say that at this stage this is only a gradual, incremental change that will not deliver a radically different fuel mix in less than a decade. "We argue that long-term aggressive deployment of renewable energy will unblock China's coal-biased technological dependence and increase supply security in all fronts," said Dr Chalvatzis, a Senior Lecturer in Business and Climate Change. "However, reduced supply diversity in China during the 1990s will not recover until after 2020s due to the long-term coal lock-in that can threaten to hold China's back from realising its full potential. "China's rapid growth rate presents a challenge as well as an opportunity for the country's energy future. The challenge is to secure increasing energy supplies while maintaining a decarbonisation path. In contrast, the opportunity lies in transforming the historical coal lock-in into a diversified and secure energy supply system that will fuel the Chinese economy for the years to come." China is the world's largest consumer of coal and its electricity sector is the largest single source of coal demand, consuming approximately half of the country's coal. Electricity consumption continues to grow rapidly, reaching a growth rate of 7.2% in the first three quarters of 2013, while electricity production for the same period grew at 6.8%. Dr Chalvatzis said: "Policy makers must design a path that will be influenced by the international energy prices and the role of technological 'dumping' caused by China or other countries. In this process climate policy, its effect on energy prices and their subsequent consequences for the well-being of the global economy will also need to be considered. "The success of China's decarbonisation path is keenly observed by the international community. The capacity of the Chinese Government to commit to international emission targets is linked to its capacity to achieve these targets without compromising its energy supply security and development prospects." Source: University of East Anglia
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Machine Learning’s Impact on Solar Energy
| Wed, 07/29/2015 - 1:00pm Lindsay Hock, Editor
IBM's solar forecasting technology. Image: IBM Research In 2013, solar was the second-largest source of new electricity generating capacity in the U.S., exceeded only by natural gas. A USA SunShot Vision Study suggests solar power could provide as much as 14% of U.S. electricity demand by 2030, and 27% by 2050. There are currently two main customers for renewable energy forecasting technologies: utility companies and independent system operators (ISOs). However, the difficulty in producing accurate solar and wind forecasts has required electric utilities to hold higher amounts of energy reserves as compared to conventional energy sources. Yet, solar power installations grow each day, and future solar penetration levels require increased attention to the value of more accurate solar forecasting. With better solar and wind forecasts, it’s possible that solar energy’s contribution to the U.S.’s energy will reach up to 50%. Until now, due to intermittency, solar energy won’t supply more than 20 to 30% of the U.S.’s energy. However, a collaboration between IBM and the U.S. Dept. of Energy (DOE) could double the accuracy of solar and wind forecasts within the next year with the help of IBM Research’s machine learning technology. “This collaboration could have a huge impact on the energy industry, as well as local businesses, the economy and the natural environment,” says Hendrik Hamann, Physical Analytics Manager, IBM Research. “Part of our goal is to help a wide range of industries and professions better understand how the world works so we can all make better decisions.” Announced on July 16, 2015, IBM Research revealed that solar and wind forecasts it’s producing using machine learning and other cognitive computing technologies proved 30% more accurate than ones created using convention approaches. The research program was funded by the DOE’s SunShot Initiative, and the results suggest new ways to optimize solar resources as they are increasingly integrated into the nation’s energy system. Machine learning for solar improvements While other solar forecasting systems take more narrow location and timeframe views, IBM’s approach incorporates a great number of weather and solar energy prediction models. “We use machine learning techniques to blend those using historical data as a function of weather situation, forecast horizon and location to create what we call a supermodel,” says Hamann. These advances are valuable for the future of alternative energy, and the machine learning model can generate accurate forecasts of solar energy from minutes ahead to several days. IBM Research worked with academic, government and industry partners for about three years to develop this self-learning weather model renewable forecasting technology, otherwise known as SMT. This technology uses a combination of machine learning, big data analytics and mathematical modeling of complex weather systems to continuously analyze, learn from and improve solar forecasts derived from a large number of weather models, including satellite observations, sensor networks and local weather stations and sky cameras. The system analyzes the data to forecast how much solar energy will be available at different locations and times. IBM’s approach provides a general platform for renewable energy forecasting, including wind and hydro. The SunShot Initiative Through the DOE SunShot Initiative, IBM Research is working with a number of collaborators in academia, government and industry to grain various perspectives. “For example, National Renewable Energy Laboratory (NREL) and ISO-New England are two main partners who are helping evaluate the important metrics to determine accuracy of solar forecasting,” says Hamann. IBM Research is also providing foundational solar forecasts covering all 48 contiguous states at 5-km spatial resolution. This is primarily for government agencies, utilities and grid operators to evaluate how solar forecasting can impact the supply and demand, in addition to operations. source: http://www.rdmag.com/articles/2015/07/machine-learnings-impact-solar-energy
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3 Exercises You Need To Do To Counteract Sitting All Day
| Fitness Lifestyle by Joel Runyon Are you a desk jockey? Do you spend most of your day sitting or hunched over a computer or laptop? According to a report from CNN, sitting all day may actually be killing you, or at the very least, could be taking years off of your life. When you sit, especially for long periods of time, your body slowly becomes more hunched over. Your internal organs get compacted and are forced to operate in less than ample space. Over time, the spine begins to weaken because of the unnatural stress placed on the joints. Hip muscles and joints begin to shorten and become tight, making standing up straight less comfortable. Ultimately, the body’s blood circulation decreases due to lack of movement. This is partially why legs and ankles will also swell during long stationary periods. The point is alarmingly clear: if you sit for long periods of time during the day, you could actually be doing your body some real harm. The great news is that there are simple foam rolling exercises that you can do in the comfort of your own home that can help your body heal, which all take less less than 15 minutes total. Grab a foam roller or a mobility ball (like a lacrosse ball) and try out these three exercises. Glute SmashIf you’re sitting on your butt all day, you need to give it some love. Most people don’t realize that rolling out your glutes will help you loosen more than just your butt muscles. You’ll also loosen your upper hamstrings and help remove some pressure from your lower back. How to do it: Place a mobility ball, or a lacrosse ball under your glute muscle on one side. Rotate the ball until you find a tight spot or “trigger point”. Contract and release the muscle (basically squeeze your butt cheek and release it) for two minutes. Keep your legs bent with the knees out to the side. Hip FlexorLike I mentioned earlier, when you sit for long periods of time, the hip muscles (including the quad and hip flexors) slowly shorten and become tighter. Tight hips make it really uncomfortable to stand up straight, and the tight joint puts a lot of unnecessary pressure on the lower back. Stretch out and open up the hips by focusing on the hip flexors. T-Spine SmashThis simple movement is one of my favorites because it helps counteract the “dreaded hunchback syndrome” so many people get from hunching over their computers every day. A great added benefit: part of this movement passes over the shoulders so you are able to help release tension that has built up throughout the week.
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sexta-feira, 31 de julho de 2015
12 Reasons You Should Visit Finland At Least Once In Your Life
Lifestyle by Julia Kitlinski-Hong
Norway and Sweden might be more popular destinations for tourists visiting Scandinavia, but Finland has many highlights that make it worth exploring as well. Here are a few reasons why you should visit Finland. You will not regret spending time in this often overlooked country in Northern Europe.
1. It Is Not As Cold As You Might Imagine
The average temperatures range from 25 F in the winter to 64 F in the summer. While the rest of their European neighbors are experiencing sometimes unbearable summer temperatures, Finns have a mild summer that makes sightseeing activities enjoyable.
2. There Is Plenty Of Space
There is a total of 5.5 million people living in Finland’s 131, 000 square miles. This comes out to about 38 people per square mile. You definitely will not feel claustrophobic here. You can have a restorative vacation while reveling in all the wide open spaces.
3. Communication Is Easy
Like the rest of its Scandinavian neighbors, Finland’s official business language is English. The added layer of having to navigate a foreign country where English is not widely spoken is not an issue at all in this country, allowing you to stress about other things — like where to eat and what to see.
4. Uses The Euro As Its Currency
Unlike its Scandinavian neighbors, Finland uses the Euro. This makes it easy if you are visiting Western Europe before or after your trip up north. Having the Euro as currency means that Finland is the cheapest Nordic destination, which will make budget travelers rejoice.
5. There Is An Advanced Technology Infrastructure In Place
Finland is famous for having the world’s largest number of cell phones and internet nodes per capita. This country is also is known for leading the way with information technology in Europe. In fact, Finland comes in second to the USA.
6. Virtually Crime Free
The extremely low-level of crime makes Finland an ideal place for solo travelers, families and elderly travelers who might feel more vulnerable than others in cities that are known to have their fair share of crime. Helsinki, the capital city, has been named the second safest city in the world.
7. There Is Endless Outdoor Activities Available
Finland is known as having 187, 888 lakes in its borders. This makes it the country with the most lakes anywhere in the world. There are plenty of places to explore “The Great Outdoors”, whether its on a boat, on wheels, or your own two feet.
8. It Has A Great Food Scene
The Finnish food scene is just getting started with a batch of young chefs making their way into the spotlight, a renewed appreciation for local ingredients, and innovative ways to create traditional dishes. What, did you think you will be eating a lot of reindeer while in Finland? If so, you’ll be in for a great surprise.
9. Stable Government
Tied with Denmark, Finland has the lowest levels of corruption in the world. This adds to the general feeling of being secure while visiting, knowing that riots against the government are not bound to break out during your visit.
10. Nature’s Spectacular Light Show
With front row seats to the Northern Lights, it’s hard to resist this brilliant display of color. For the optimal viewing, make sure to do some research beforehand, because these lights cannot be seen every night.
11. Experience The Never-Ending Daylight
In the summertime, the sun can be in the sky for a twenty-four hour period. This is a unique natural phenomenon that should be experienced at least once in your life.
12. Staying Warm in A Finnish Sauna
Saunas in Finland are a common recreational activity where Finns go both to socialize and use for its relaxation purposes. There are reportedly three million saunas in Finland, a lot of them in private households.
Featured photo credit: Flickr via flickr.com
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Baines&Fricker reveal a stylish portable research lab for Fieldwork
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Baines&Fricker were commissioned by consultancy firm Fieldwork to design and make a portable research lab. The lab comes in a custom built flightcase with rollers on one side. The flightcase doubles as a base when stood on one end and the lab’s front panel pulls forward to create a desk. According to Fieldwork founder Curtis James, “Fieldwork do ethnographic research into working life, which entails making visible the ordinary and extraordinary things that might go unnoticed in day to day office life.” This new portable research lab allows them to advance their work in a stylish, convenient way. source: http://inhabitat.com/bainesfricker-reveal-a-stylish-portable-research-lab-for-fieldwork/
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How to Maintain a Healthy Work-Life Balance in the Age of Technology
| We are living in a digital age and are always connected to our computers, tablets and smartphones. Just a few decades ago, when the workday ended at 5:00PM, workers packed up and turned their minds off for the evening. However, because of our constant connection through technology, client emails, proposals and projects have become a part of time spent outside of the office. These extra hours and inability to step away from work have caused many individuals to call for a work-life balance, which places an emphasis on juggling work and maintaining a personal life with family and friends outside of the office. Here are some suggestions for succeeding with work and your personal life both inside and outside of the office: Incorporate Physical Activity Into Your RoutineIncorporating physical activity into your routine is an important part of maintaining a work-life balance. Physical activity not only helps to refresh both your mind and body, but also provides mental clarity during a time of stress at work. In addition to this, it keeps your body in optimal physical shape, which makes you feel more productive and healthy. Summer is the perfect time to place an emphasis on physical activity. If your schedule does not allow for going to the gym before or after work consider making this a part of your workday. Step away from your desk and take a walk with a co-worker to gain a new perspective and exercise your muscles. Separating from Electronic DevicesAnother important aspect of maintaining a work-life balance is separating from electronic devices during evenings and weekends. If you feel the need to complete extra work or respond to emails outside of the office designate a specific time for these responses. For example, allow yourself to complete work in the evenings from 6-8 and then close your laptop. Or, respond to emails Saturday morning and then take Sunday off. Find what works best for you and your schedule and make a point to separate from electronic devices and clear your mind. While spending time working outside of the typical 9-5 has become normal in our current workforce, working all day every day is not efficient and will eventually cause you to burn out. Make Work ProductiveThe Internet and social media have made our lives faster and easier. Workplace communication that previously took place in the form of long meetings and phone calls has been replaced by quick email and instant message exchanges. While the use of technology for communication has saved us time, it can often serve as a distraction as well. This is important to keep in mind at the office. When you are at work make it productive and spend your hours completing projects and assignments instead of surfing the web or checking Facebook. Consider keeping a time-sheet to monitor your hours and stay on task. Incorporate Downtime Into Your RoutineTake some time to do what you love whether that means spending time with friends and family or investing in a hobby. Having an active social life often correlates with having a positive work life so make sure to invest in what makes you happy outside of the office. This will provide you a sense of meaning and allow you to define yourself outside of a work role. Feeling overwhelmed by a situation or project at work? Sometimes the best ideas come when your mind is refreshed and focused. Grabbing dinner with a friend and discussing your situation may provide new light and a solution to your problem. Take some time to see how others in your office maintain a work-life balance and follow their lead. They may have tips to help you achieve the work-life balance you have been looking for.
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10 Reasons to Focus on Steps, Not Goals
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Productivity Success by Matt Duczeminski When you want to improve an aspect of your life, it’s important to set goals. This is how you know where you want to end up. However, once you’ve set a goal for yourself, you should focus on the small steps you’ll be taking in order to reach this goal. You should always keep your final destination in sight, but know that it’s the small steps that will guide you there. Here’s what you can expect by keeping the small steps in mind. 1. You won’t feel intimidatedMaybe your goal is to become a master guitarist, but you don’t even know how to play a chord. It can be incredibly intimidating to watch a Grateful Dead concert as Jerry Garcia moves up and down the fret board for hours without breaking a sweat. You’ll most likely get the feeling that you’ll “never be able to do that,” and run the risk of quitting before you even get started. By taking small steps toward your goal, you’ll feel less intimidated when you see others who are above your level. 2. You’ll see progress constantlyIf you’re constantly looking at your endgame as your only goal, you won’t think you’re getting anywhere when you make a small improvement in your skills. When you focus on the small steps, you’ll see progress almost instantaneously. Yesterday, you might have set out to memorize the order of the guitar strings. It can be highly motivating to see this goal accomplished. It might not seem like a huge accomplishment, but you’ll know you’re one step closer to achieving your overall goal. 3. You’ll appreciate the processWhen you focus on the small steps, you’ll realize that even the experts have been in your shoes at one point in their lives. It’s hard to imagine a time in which Garcia didn’t know the difference between an E and an A string, but he had to have started somewhere, right? The small steps might be boring at times — do you think Michael Jordan really loved taking foul shots all day? — , but going through them is an absolute necessity if you want to reach your goal. 4. You’ll learn the basicsIt might be tempting to skip steps at times in order to reach your goal faster. However, this will only lead to confusion and frustration in the long run. Imagine a child trying to learn multiplication before he or she learns how to add. So much instruction would be lost in this method that the child wouldn’t possibly be able to succeed. The old saying is true: “You have to learn to crawl before you can walk.” Take baby steps to ensure you can handle the small stuff before moving on to the big time. 5. You’ll learn moreWhile you’re learning the basics, you should slow down and try different methods to accomplish your short-term goals. There’s always more than one way to get something done. Going about a task in a variety of ways will lead you to the most efficient way for you to complete the task at hand. You might learn something about the whole process that you would have missed had you rushed through the small steps. 6. You’ll understand the fundamentalsIt’s not enough just to complete the small tasks — you have to understand why you completed them. Tuning a guitar might seem pretty straight-forward, as you can just memorize each string’s open note and tune it. However, it’s important to take the time to understand the relationship between the strings, and how each is utilized when forming chords and scales. Go beyond rote memorization and truly comprehend each step as you progress toward your goal. 7. You’ll anticipate successIf you schedule the small goals to be accomplished, you’ll know on Wednesday what you’ll be able to do on Friday. This not only gives you an idea about how you’re moving forward, but it also motivates you to keep up the hard work. If you schedule out your week of practice and growth, skipping a day will set everything back. When you’ve put it all in writing, you’ll be even more motivated not to let yourself down. 8. You’ll adapt your goalsThen again, some days you might not do as well as you’d hoped you would. That’s certainly alright. By setting mini-goals along the way, you’ll be able to modify them depending on your progress the previous day. While you would most likely feel disappointed in yourself for skipping a day of work, there’s no shame in getting stuck on a previous step as long as you’re making strides to overcome it. 9. You’ll celebrate small victoriesWhen you set smaller goals, you’ll be able to celebrate more. Like I said, making a schedule and anticipating success will allow you set your sights on a short-term goal, possibly a week-long one. Once you reach that smaller goal, you’ll definitely feel much more accomplished than you would if you’d reached that point without considering it a “goal.” Every small accomplishment is reason to celebrate, so don’t downplay your improvements. 10. You’ll keep pushing yourselfIf you set one major goal for yourself at the beginning of your journey, you run the risk of becoming complacent once you reach that goal. For example, if your goal was to run a six-minute mile, and it took you months to get to that point, you might just breathe a sigh of relief and consider yourself a success. While that would undoubtedly be a great accomplishment, there’s still room for improvement. If you had spent months improving your time and acknowledging each incremental improvement, you’re more apt to celebrate your milestone and then get back up the next day and work to shatter your own record. Love this article? Share it with your friends on Facebook Matt is a part-time freelance writer trying to make the move to full time, so be prepared to be inundated with articles you may or may not find interesting. Hopefully you do. No, you definitely will. Catch up with me on LinkedIn or Twitter! source : www.lifehack.org
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O valor do alimento que é jogado fora
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O valor nutricional de frutas e legumes não é nenhuma novidade. O que as pessoas não sabiam é que as cascas, folhas e talos de alguns desses alimentos possuem nutrientes como vitamina C, carboidratos, cálcio e fibras, muitas vezes em quantidades superiores às da própria polpa. Essa descoberta faz parte de uma pesquisa desenvolvida no Instituto de Biociências (IB), campus de Botucatu, que avaliou o valor nutricional, em cada 100 gramas, de 20 espécies de frutas e hortaliças das mais consumidas pelos brasileiros. O estudo integra o projeto Alimente-se Bem, promovido pelo Serviço Social da Indústria (Sesi) de São Paulo, que ensina donas-de-casa de comunidades carentes a preparar receitas baratas e nutritivas. (Leia texto na página ao lado.) “Sempre soubemos que as cascas também contêm vitaminas e nutrientes, mas não conhecíamos a quantidade dessas substâncias”, comenta Tereza Watanabe, diretora de Alimentação do Sesi-SP, que solicitou a ajuda da UNESP para a realização do projeto. “Por falta de conhecimento da população sobre o valor nutricional dos talos, folhas e cascas e como aproveitá-los nos pratos, eles acabam indo para o lixo, algo inadmissível em um país em que a desnutrição atinge cerca de 22 milhões de pessoas”, comenta Giuseppina Lima, docente do Departamento de Química e Bioquímica do IB e coordenadora da pesquisa. Presença da vitamina C A folha da couve-flor foi o produto que mais surpreendeu os pesquisadores. Embora geralmente não seja aproveitada no preparo de pratos, o estudo constatou que 100 g da folha contêm 122 mg de vitamina C, quantidade quatro vezes maior do que no mesmo volume da polpa da laranja, por exemplo. A casca do mamão, por sua vez, registrou 52 mg. “Esses dois alimentos possuem níveis acima da dose diária de 45 mg da vitamina, recomendada pelos médicos”, aponta Giuseppina. A vitamina C é um dos nutrientes mais importantes para o organismo. Sua carência pode levar a distúrbios neurológicos, dores musculares, perda de dentes e ao escorbuto, doença que provoca hemorragia nas gengivas. Outra função importante é a de neutralizar a ação dos radicais livres, moléculas associadas ao envelhecimento e à formação de tumores. Goiaba, acerola, morango, tomate, pimentão, manga, caju e limão também têm bons níveis da vitamina. Já em 100 g de casca de laranja, os pesquisadores acharam 107 mg de fósforo, volume bem superior ao verificado na polpa da fruta (18 mg). Esse elemento químico é utilizado pelas células humanas para armazenar e transportar energia em forma de calorias. “O fósforo potencializa os efeitos de algumas vitaminas, especialmente as do complexo B, que ajudam a transformar os carboidratos, lipídios e proteínas em energia, fortalecendo os sistemas neurológico, dermatológico e gastrintestinal”, revela Giuseppina. No estudo, essa substância foi encontrada ainda na casca do mamão, no talo do espinafre, na folha e no talo da salsinha. Na casca da laranja, também foi detectado cálcio na concentração de 362 mg. Outro destaque foram as folhas do salsão, com 66 mg dessa substância, que faz parte da constituição dos ossos, dentes e músculos. “É um mineral que controla a atividade hormonal, evita contraturas musculares e cãibras, além de auxiliar a transmissão de impulsos nervosos”, esclarece Suraya Rocha, que realizou, com esse estudo, a sua dissertação de mestrado no IB. Níveis de carotenóides Em quantidade de 68 mg, o cálcio também é encontrado na rama da cenoura, cuja polpa é rica em carotenóides (119 mg). Esses pigmentos, responsáveis pela cor dos alimentos, auxiliam o crescimento ósseo e estão relacionados à vitamina A, sendo antioxidantes associados à prevenção do câncer de pulmão, pele e estômago. São recomendados, ainda, em casos de doenças cardiovasculares, aids e processos ligados ao envelhecimento, como o mal de Alzheimer. As cascas de abóbora, goiaba e mamão são outros produtos que apresentam esses pigmentos. “Nos vegetais, os níveis de carotenóides aumentam à medida que eles amadurecem”, observa Suraya. Na rama da cenoura, as análises identificaram teor de 25 mg de ferro, quantidade necessária para suplementação diária de homens e mulheres. A deficiência desse elemento, responsável pelo transporte do oxigênio na hemoglobina do sangue, costuma causar anemia. “Trata-se de um dos minerais mais importantes na absorção de substâncias fundamentais para a vida”, afirma Pedro Magalhães Padilha, que integrou o grupo do IB. Outro produto rico em nutrientes é a casca de limão, que possui 3 g de proteínas a cada 100 g, o maior volume entre as frutas estudadas. “Compostas por vários aminoácidos que ajudam a formação de novas proteínas, elas são ligadas ao bom funcionamento do sistema de defesa, que combate bactérias e vírus”, aponta Padilha. As cascas de limão também se mostraram as mais ricas em fibras, com 6,7 g. O baixo consumo de fibras pode originar problemas que vão de prisão de ventre a câncer de cólon. Seu consumo reduz os índices de glicemia e colesterol no sangue, o que previne as doenças do coração. Componentes de muitas frutas, hortaliças e cereais, as fibras são encontradas ainda nas cascas de laranja Dieta mais saudável O estudo demonstra que as camadas externas de várias frutas são ricas em carboidratos, que fornecem energia às células, fortalecem a parede celular e servem de reserva energética. As cascas do abacaxi (4 g), da maçã (4,7 g) e da laranja (12 g) podem ser aproveitadas em várias receitas de bolos e sobremesas. De qualquer forma, a polpa da banana superou todos os demais produtos analisados, com 14 g de carboidratos. Um grama de carboidrato possui 3,7 calorias – valor utilizado para medir o valor energético dos alimentos. Outro componente importante das cascas de algumas frutas são os lipídios, encontrados principalmente no limão (0,9 g), na laranja (0,7 g) e na maçã (0,7 g). “Cada grama dessas moléculas de gordura possui 9 calorias de energia”, destaca Giuseppina. “Eles fazem parte da membrana celular e exercem no organismo um importante papel de transportar elétrons, hormônios e vitaminas A, D, E e K.” A pesquisadora ressalta que é recomendável o consumo de 80 g de lipídios por dia. Um dos nutrientes mais importantes para a formação dos dentes e ossos nas crianças, o potássio foi encontrado (2,3 mg) nas folhas do salsão. A substância também aparece em quantidades expressivas na rama da cenoura (1,1 mg), na casca do limão (1,9 mg) e no talo do espinafre (1,0 mg). A casca de banana tem o dobro de potássio, 0,9 g, em relação ao encontrado na polpa da fruta, com 0,4 g. A carência de potássio causa fraqueza, desorientação mental e fadiga muscular. Segundo Giuseppina, os próximos passos da pesquisa serão ampliar o número de espécies vegetais analisadas e comparar os valores nutricionais com as formas de cultivo e armazenamento dos alimentos. “Vamos continuar a estudar partes geralmente descartadas dos vegetais, para proporcionar à população uma dieta mais saudável; afinal de contas, uma alimentação balanceada é o primeiro passo para uma vida saudável”, argumenta. Receitas com talos, folhas e ramos Arroz verdinho Bolo de casca de banana Patê de salsa Caldo Verde Quiche de casca de abóbora Na Internet Estudantes ensinam receitas baratas ados da Coordenadoria de Abastecimento da Secretaria de Agricultura e Abastecimento do Estado de São Paulo estimam que o País perde o equivalente a 1,4% do PIB com alimentos não aproveitados. O volume poderia alimentar 19 milhões de pessoas com três refeições diárias. Para combater esse desperdício e oferecer uma alimentação mais saudável à população, o Serviço Social da Indústria em São Paulo (Sesi) criou, em 1999, o Programa Alimente-se Bem. Receitas com partes dos alimentos geralmente descartadas, como talos, cascas e folhas, são elaboradas e testadas nas cozinhas experimentais da entidade e depois servidas em seus restaurantes do Estado. Diretora de Alimentação do Sesi, Tereza Watanabe enfatiza que o projeto começou a partir de uma pesquisa que detectou que 65% dos trabalhadores das indústrias se alimentavam mal. Depois de uma reformulação nos cardápios oferecidos, em 2003, um outro levantamento constatou a aprovação de 84% em relação a essa inovação. “A mudança de paradigma na alimentação passou pela apresentação dos pratos e seu preparo com receitas deliciosas e nutritivas”, comenta Tereza. Participação de alunos Além da pesquisa sobre o valor nutritivo de frutas e legumes, a UNESP participa do programa na divulgação das receitas elaboradas pelas nutricionistas do Sesi para donas-de-casa, principalmente de bairros carentes. Em Botucatu, estudantes do 4o e 5o anos do curso de Nutrição do IB percorrem a cidade em um ônibus-escola para ensinar as receitas. Doado pela prefeitura local, o coletivo está equipado com forno elétrico, fogão, microondas, geladeiras e utensílios de cozinha. “O mais importante para os alunos é o contato com o público, que apresenta várias questões sobre os tipos de alimento que fazem bem à saúde, o que nos leva a pesquisar e ficar mais atualizados”, diz a quintanista Reila Castaldeli. Aluna do 4o ano, Keny Tirapeli revela que, depois de participar do projeto, também passou a reaproveitar alimentos e fazer sobremesas com cascas de frutas. Desde 2001, em todo o Estado de São Paulo, 360 mil pessoas já passaram pelos cursos e palestras. Nos restaurantes educativos, 4 milhões de refeições foram servidas utilizando receitas que integram um livro com tiragem de mais de 100 mil exemplares. O programa está sendo implantado em 26 Estados pelo Ministério do Desenvolvimento e Combate à Fome do Governo Federal. Em abril, foi lançado um novo livro, o Alimente-se Bem – Fundamentos, Estratégias e Realizações, que traz o estudo dos pesquisadores da UNESP sobre o valor nutricional de frutas e legumes.
Julio Zanella
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Major milestone in molecular electronics
 Schematic of the molecular junction created using asymmetric area electrodes which functions as a diode, allowing current to flow in one direction only. Credit: Berkeley Lab and Columbia University A team of researchers from Berkeley Lab and Columbia University has passed a major milestone in molecular electronics with the creation of the world's highest-performance single-molecule diode. Working at Berkeley Lab's Molecular Foundry, a U.S. Department of Energy (DOE) Office of Science User Facility, the team used a combination of gold electrodes and an ionic solution to create a single-molecule diode that outperforms the best of its predecessors by a factor of 50. "Using a single symmetric molecule, an ionic solution and two gold electrodes of dramatically different exposed surface areas, we were able to create a diode that resulted in a rectification ratio, the ratio of forward to reverse current at fixed voltage, in excess of 200, which is a record for single-molecule devices," says Jeff Neaton, Director of the Molecular Foundry, a senior faculty scientist with Berkeley Lab's Materials Sciences Division and the Department of Physics at the University of California Berkeley, and a member of the Kavli Energy Nanoscience Institute at Berkeley (Kavli ENSI). "The asymmetry necessary for diode behavior originates with the different exposed electrode areas and the ionic solution," he says. "This leads to different electrostatic environments surrounding the two electrodes and superlative single-molecule device behavior." With "smaller and faster" as the driving mantra of the electronics industry, single-molecule devices represent the ultimate limit in electronic miniaturization. In 1974, molecular electronics pioneers Mark Ratner and Arieh Aviram theorized that an asymmetric molecule could act as a rectifier, a one-way conductor of electric current. Since then, development of functional single-molecule electronic devices has been a major pursuit with diodes -- one of the most widely used electronic components -- being at the top of the list. A typical diode consists of a silicon p-n junction between a pair of electrodes (anode and cathode) that serves as the "valve" of an electrical circuit, directing the flow of current by allowing it to pass through in only one "forward" direction. The asymmetry of a p-n junction presents the electrons with an "on/off" transport environment. Scientists have previously fashioned single-molecule diodes either through the chemical synthesis of special asymmetric molecules that are analogous to a p-n junction; or through the use of symmetric molecules with different metals as the two electrodes. However, the resulting asymmetric junctions yielded low rectification ratios, and low forward current. Neaton and his colleagues at Columbia University have discovered a way to address both deficiencies. "Electron flow at molecular length-scales is dominated by quantum tunneling," Neaton explains. "The efficiency of the tunneling process depends intimately on the degree of alignment of the molecule's discrete energy levels with the electrode's continuous spectrum. In a molecular rectifier, this alignment is enhanced for positive voltage, leading to an increase in tunneling, and is reduced for negative voltage. At the Molecular Foundry we developed an approach to accurately compute energy-level alignment and tunneling probability in single-molecule junctions. This method allowed myself and Zhenfei Liu to understand the diode behavior quantitatively." In collaboration with Columbia University's Latha Venkataraman and Luis Campos and their respective research groups, Neaton and Liu fabricated a high-performing rectifier from junctions made of symmetric molecules with molecular resonance in nearly perfect alignment with the Fermi electron energy levels of the gold electrodes. Symmetry was broken by a substantial difference in the size of the area on each gold electrode that was exposed to the ionic solution. Owing to the asymmetric electrode area, the ionic solution, and the junction energy level alignment, a positive voltage increases current substantially; a negative voltage suppresses it equally significantly. "The ionic solution, combined with the asymmetry in electrode areas, allows us to control the junction's electrostatic environment simply by changing the bias polarity," Neaton says. "In addition to breaking symmetry, double layers formed by ionic solution also generate dipole differences at the two electrodes, which is the underlying reason behind the asymmetric shift of molecular resonance. The Columbia group's experiments showed that with the same molecule and electrode setup, a non-ionic solution yields no rectification at all." The Berkeley Lab-Columbia University team believes their new approach to a single-molecule diode provides a general route for tuning nonlinear nanoscale-device phenomena that could be applied to systems beyond single-molecule junctions and two-terminal devices. "We expect the understanding gained from this work to be applicable to ionic liquid gating in other contexts, and mechanisms to be generalized to devices fabricated from two-dimensional materials," Neaton says. "Beyond devices, these tiny molecular circuits are petri dishes for revealing and designing new routes to charge and energy flow at the nanoscale. What is exciting to me about this field is its multidisciplinary nature -- the need for both physics and chemistry -- and the strong beneficial coupling between experiment and theory. "With the increasing level of experimental control at the single-molecule level, and improvements in theoretical understanding and computational speed and accuracy, we're just at the tip of the iceberg with what we can understand and control at these small length scales." Story Source: The above post is reprinted from materials provided by DOE/Lawrence Berkeley National Laboratory. The original item was written by Lynn Yarris. 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