Minhas músicas preferidas –1– Let me call you sweetheart -

Acute use of cannabinoids depresses motor neuron activity

New research could explain the acute lack of coordination and difficulty speaking and breathing experienced by some people who use cannabis. Why do some habitual marijuana users have difficulties speaking, breathing or swallowing food? Is it true that people who use this substance may suffer acute lack of motor coordination? Does the use of cannabis cause muscular weakness? These questions have been addressed by researchers of the NeuroDegeneration and NeuroRepair Group of the University of Cadiz, directed by professor Bernardo Moreno, and who recently published a study related to this topic in the journal Neuropharmacology. This study reveals that synthetic analogues of the psychoactive compounds of marijuana significantly reduce the activity of motor neurons. To fully understand the importance of this discovery, it is necessary to bear in mind that up until now there were no studies focusing on this subject. All the work known to date related to cannabis and its effects had been based on the psychomotor mechanisms (the higher central nervous system) and there was no study focused on describing the direct impact of cannabinoids on the neurons that control the muscles, that is, the motor neurons. Therefore, at the University of Cadiz it was decided to work on this topic using the motor hypoglossal nucleus (that controls the movements of the tongue) as a model, given that "the tongue is an important muscle used in respiratory phenomena, in speech, it is necessary to swallow food, i.e., it has many functions that in cannabis users, appear to be disrupted," explains professor Bernardo Moreno. Thus, "during the investigation, we used an animal model in which we studied the alterations produced by synthetic cannabinoids on the activity of the motor neurons of the hypoglossal nucleus. In doing so, we discovered that these psychoactive compounds inhibit the information that reaches these neurons via the synapses (structures specialized in the communication of information between neurons). In other words, cannabinoids hinder the transmission of information between neurons." A consequence of this fact is, for example, that muscular weakness is produced as "the motor neuron, that is the one that gives the order to the muscle to contract, sees its activity reduced which, as a consequence, would weaken the strength of the muscle contraction," as doctor Moreno points out. All of this could lead to problems speaking, breathing and even swallowing food. Nevertheless, this action mechanism could also explain the beneficial therapeutic effects that marijuana has on motor disturbances in people suffering from neurodegenerative diseases such as multiple sclerosis for example, given that "in pathological processes associated with muscular hyperactivity phenomena, the reduction in motor neuron activity induced by cannabis could lead to a symptomatological improvement." This study, carried out as a consequence of the studies on synaptic mechanisms performed by this group at the University of Cadiz, opens a new avenue of research for the scientific community. In spite of this, "our work will be steered towards other territories. At this time we are in the middle of a study focusing on the effects of cannabinoids as possible mediators of synaptic plasticity (phenomenon involved in motor learning), although it must be made clear that these compounds are not the central theme of the work of our research group," concludes Bernardo Moreno. In order to carry out this study, the work of the researchers of the UCA, Victoria García Morales (pre-doctoral scholarship holder at the UCA) and Fernando Montero (postdoctoral contract from the Junta de Andalucía) has been fundamental and, directed by professor Bernardo Moreno, they have carried out all the experimental stages. Equally, we must mention that this discovery has been made thanks to the funding of two research projects, one by the Ministry of Science and Innovation, now the Ministry of Economy and Competitiveness, and the other by the Junta de Andalucía.

Scientists bring oxygen back to dead fjord

Deployment of scientific instrumentation for measuring microbial processes in the sediment is shown: Byfjord, Sweden. More and more of the world's waters are seriously lacking oxygen. Could we use pumps to bring oxygen and thus higher life back into these waters? A Danish/Swedish research team says yes. They installed pumps in a Swedish fjord that showed a strong oxygen deficit and now they report that all the right oxygen-loving organisms have come back to the fjord. Lack of oxygen is a major problem in many of the world's waters. Both big oceans and small fjords are affected, and climate models predict an increase of this phenomenon in the future. To bring oxygen and thus higher life back to these waters is a huge task. But maybe it is possible -- at least judging by a pilot project in a Swedish fjord. "Our Swedish colleagues got the idea to use a pump to mix oxygen-rich surface water into the deeper parts of the water column in the fjord which was lacking oxygen," says postdoc Michael Forth and Associate Professor Alexander Treusch from the Nordic Center for Earth Evolution, Institute of Biology at the University of Southern Denmark. Could also help the Baltic Sea The Swedish part of the team, Professor Anders Stigebrandt and Dr. Bengt Liljebladh from the Department of Earth Sciences, Oceanography, and Professor Per Hall from the Department of Chemistry and Molecular Biology, Marine Chemistry at the University of Gothenburg, were interested if pumps could support and enhance natural venting events, that bring oxygen-rich water into deeper parts of the water column. Ultimately such an approach could be used to increase water quality in the oxygen-lacking Baltic Sea, they believe. To test these ideas, a large-scale experiment was conducted in a Swedish fjord called Byfjord, which is located near the town of Uddevalla. Similarly to the Baltic, the four kilometer long and 1.5 m wide fjord has a shallow entrance with a deeper basin that, in the case of the fjord, is 51 m deep. The water in the fjord's deep basin doesn't get mixed as oxygen-rich water coming in from the Kattegat Ocean and the river Bävenå exchanges only the surface water. Therefore the bottom waters suffer from a long-term lack of oxygen. The pump was used during multiple periods between 2010 and 2013 to bring oxygen-rich water from the fjord's surface down to about 35 meters depth. The surface water then was naturally and instantly replaced with new water from the Kattegat Ocean, creating inflows of oxygen-rich water into the fjord. Two months of pumping Did the experiment work? After two months of pumping, higher oxygen concentrations became detectable in the bottom waters. Forth says "Already while the pumps were working we could see how some oxygen requiring bacteria returned into the deeper water of the fjord and some that don't like oxygen disappeared." Before the pumps were used, the anoxic bottom waters were home to certain groups of bacteria, e.g. the so-called SUP05 clade and Desulfocapsa bacteria. These microorganisms use nitrate or sulphate instead of oxygen for respiration. As part of this lifestyle the SUP05 and similar bacteria transform sulfur, carbon and nitrogen in such large quantities that it can change the chemical composition of an ocean and can contribute to the production of climate-active gases. "At the same time as we saw the SUP05 bacteria disappearing from the fjord's bottom waters, the oxygen-requiring SAR11 clade bacteria appeared. Until then they had only lived in the surface water," say Forth and Treusch and continue: "In the later phase of the experiment the entire water column began to look healthy. Many of the oxygen-needing bacterial species had returned and new bacterial communities similar to those in natural oxic fjords formed. This showed us that the idea worked." 50 pct of bottom water was replaced For obvious reasons the scientists do not know if the oxygen levels in the fjord will begin to fall again in the future, now that the pumps have stopped. But initially there was no sign of this happening. "It seems that the fjord "only" needs help from time to time to restore the oxygen levels and then can maintain them for a longer period of time on its own," the researchers said. Overall, 50 per cent of the Byfjords bottom water (below 15 meters) was replaced with fresh oxygen-rich water from the Kattegat Ocean in the frame of the experiment. The results from the Swedish fjord may have implications for the whole Baltic Sea. "The bacterial communities in the Baltic Sea are very similar to those in Byfjord before the fjord was aerated. So it is fair to imagine that the same change in the bacterial community will take place in the Baltic Sea if we start to pump oxygen-rich water down to the bottom waters of the Baltic Sea. This is an idea our Swedish colleagues are investigating further," say Forth and Treusch. Facts about lack of oxygen in world oceans Lack of oxygen in the oceans is an increasing problem. Climate models indicate that the large anoxic areas, called Oxygen Minimum Zones (OMZs), are growing. Growing OMZs may lead to an increase in the loss of organic nitrogen and affect the global carbon cycle. There are very large OMZs off the coast of Chile and in the Arabian Sea.

How a wound closes

Epithelial cells move collectively out of their original shape (left) into the environment (right). Localisation of Merlin is shown in green, the cell nuclei in red. For wounds to close, cells need to move collectively in one direction in a coordinated fashion. Until now the central molecular mechanism that allows cells to coordinate these movements over larger distances has been unclear. Now researchers from Heidelberg University and the Max Planck Institute for Intelligent Systems in Stuttgart have succeeded in decoding it. Collective cell migration is not only important in wound healing, but also in the development of the embryo and even of cancer. The results of their research, published in the journal "Nature Cell Biology," have tremendous implications for all three of these areas. "The collective migration of cells and biological systems is one of the most important natural phenomena and occurs in nature at different levels and length scales. We have now identified the key molecular player and the related mechanism that controls the collective migration of epithelial cells, that is the covering layer of skin cells," explains Prof. Dr. Joachim Spatz of the Institute for Physical Chemistry at Heidelberg University and the Max Planck Institute for Intelligent Systems. In their investigation, the researchers introduce a complete molecular mechanism that focuses on the protein called Merlin. The results link intercellular mechanical forces to collective cell movements and also demonstrate how local interactions give rise to collective dynamics at the multicellular level. "They create an analogy with what we already know about collective movements observable in both the biological and physical world," explains Prof. Spatz. The researcher compares the process of cell migration to running a marathon. "At the level of the organism, an individual in a collective consciously tries to align its movements with those of its neighbours, which involves orchestrated sensing and action." Within a cellular collective, these two processes are linked via signal transduction pathways. There is a lead cell in the collective, similar to the leader in a marathon. It is mechanically connected to its follower cells by cell-to-cell contacts. The forward motion of the lead cell puts mechanical tension on the follower cells, according to Spatz. The merlin protein senses this mechanical tension and initiates spatially polarised following movement. This transmits the mechanical tension among the follower cells from one cell to the next. The follower cells respond by forming 'leg-like' protrusions directed at the lead cell in order to move forward. "Until now it has been unclear what molecular link connects these two events, sensing and action," says Joachim Spatz. "Our study now shows how the mechanosensitive Merlin protein converts cellular forces to collective cell motions by acting as a mechanochemical transducer. What's truly astonishing is that Merlin is the only protein in the responsible signal network that conveys this property to cellular collectives -- that there are no replacement mechanisms. If Merlin fails, the cells lose their ability to move collectively and trigger the related medically relevant, pathophysiological properties in the organism." The major player in the study, Merlin, is also a known tumour suppressor that is responsible for several types of cancer. Merlin is also a regulator of the Hippo pathway, an important signal pathway in biology that controls cell proliferation and organ size. It has been preserved in evolution since the emergence of primitive multicellular organisms. "It's exciting to see a connection between these seemingly disparate fields, linked by a Merlin-mediated signalling mechanism," says the researcher. Story Source: The above story is based on materials provided by Heidelberg, Universität. Note: Materials may be edited for content and length. Journal Reference: Tamal Das, Kai Safferling, Sebastian Rausch, Niels Grabe, Heike Boehm, Joachim P. Spatz. A molecular mechanotransduction pathway regulates collective migration of epithelial cells. Nature Cell Biology, 2015; DOI: 10.1038/ncb3115 Cite This Page:

Your privacy online: Health information at serious risk of abuse, researchers warn

An analysis of over 80,000 such web pages shows that nine out of ten visits result in personal health information being leaked to third parties, including online advertisers and data brokers. There is a significant risk to your privacy whenever you visit a health-related web page. An analysis of over 80,000 such web pages shows that nine out of ten visits result in personal health information being leaked to third parties, including online advertisers and data brokers. This puts users are risk for two significant reasons: first, people's health interests may be publicly identified along with their names. This could happen because criminals get ahold of the information, it is accidentally leaked, or data brokers collect and sell the information. Second, many online marketers use algorithmic tools which automatically cluster people into groups with names like "target" and "waste." Predictably, those in the "target" category are extended favorable discounts at retailers and advance notice of sales. Given that 62 percent of bankruptcies are the result of medical expenses, it is possible anyone visiting medical websites may be grouped into the "waste" category and denied favorable offers. For individuals, this means profiles are built based on web page visits, potentially resulting in someone being labeled a commercial risk due to the fact that they have used a site like WebMD.com or CDC.gov to look up health information for themselves, a family member, or a friend. Given that data brokers are free to sell any information they collect regarding visits to health websites, those visiting such sites are potentially at risk of being discriminated against by potential employers, retailers, or anybody else with the money to buy the data. These findings are reported in the article "Privacy Implications of Health Information Seeking on the Web," appearing in the March 2015 issue of Communication of the ACM. Timothy Libert, a doctoral student at the University of Pennsylvania's Annenberg School for Communication wrote the article. He authored a software tool that investigates Hypertext Transfer Protocol (HTTP) requests initiated to third party advertisers and data brokers. He found that 91 percent of health-related web pages initiate HTTP requests to third-parties. Seventy percent of these requests include information about specific symptoms, treatment, or diseases (AIDS, Cancer, etc.). The vast majority of these requests go to a handful of online advertisers: Google collects user information from 78 percent of pages, comScore 38 percent, and Facebook 31 percent. Two data brokers, Experian and Acxiom, were also found on thousands of pages. "Google offers a number of services which collect detailed personal information such as a user's persona email (Gmail), work email (Apps for Business), and physical location (Google Maps)," Libert writes. "For those who use Google's social media offering, Google+, a real name is forcefully encouraged. By combining the many types of information held by Google services, it would be fairly trivial for the company to match real identities to "anonymous" web browsing data." Indeed, in 2014, the The Office of the Privacy Commissioner of Canada found Google to be violating privacy Canadian laws. "Advertisers promise their methods are wholly anonymous and therefore benign," Libert writes. "Yet identification is now always required for discriminatory behavior to occur." He cites a 2013 study where individuals' names were associated with web searches of a criminal record, simply based on whether someone had a "black name." "Personal health information -- historically protected by the Hippocratic Oath -- has suddenly become the property of private corporations who may sell it to the highest bidder or accidentally misuse it to discriminate against the ill," Libert said. "As health information seeking has moved online, the privacy of a doctor's office has been traded in for the silent intrusion of behavioral tracking." Online privacy has for some time been a concern. Studies conducted by Annenberg dating back to 1999 indicate wariness among Americans about how their personal information may be used. And slightly more than one in every three Americans even knows that private third-parties can track their visits to health-related websites. Libert points out that the Federal Health Insurance Portability and Accountability Act (HIPPA) is not meant to police business practices by third party commercial entities or data brokers. The field of regulation is widely nonexistent in the U.S., meaning that individuals looking up health information online are left exposed and vulnerable. According to Libert, "Proving privacy harms is always a difficult task. However, this study demonstrates that data on online health information seeking is being collected by entities not subject to regulation oversight. This information can be inadvertently misused, sold, or even stolen. Clearly there is a need for discussion with respect to legislation, policies, and oversight to address health privacy in the age of the internet."

O Professor Pardal ataca novamente–parte II

Na postagem  em que disserto sobre inventos e onde apresento a minha ideia para se aproveitar a força da gravidade, ao reler a postagem sobre as bóias que aproveitam a força das ondas para gerar eletricidade,  estas simplesmente sustentam o mecanismo principal que gera eletricidade e que fica ligado abaixo da bóia. O movimento das ondas do mar produzem um movimento linear no mecanismo e uma empresa sueca desenvolveu um sistema para transformar o mocimento linear em movimento rotatório. É esse movimento rotatório que irá efetivamente gerar eletricidade usando-se alguma tecnologia que não foi possível descobrir na postagem já que obviamente deve tratar-se de algo secreto. Então, na minha idéia do peso descendo sob a ação da gravidade, o movimento linear também poderia ser transformado em movimento rotativo. A diferença é que no lugar das ondas do mar como fonte de energia, usa-se a força da gravidade. E o alternador seria substituido pelo mesmo sistema usado no sistema das bóias.  (continua no próximo capítulo) Ia esquecendo de mencionar. Quem se aventurar no projeto que idealizei e se der bem, favor enviar para a conta 876-98675-r54t-6745 do Banco da Praça, 10% dos rendimentos obtidos com a venda das máquinas já que a ideia foi minha. Obrigado de antemão.

Alimentos que devem compor a sua dieta

Publicado em 22/02/2015 por galdinopinto em Alimentação Conheça 8 alimentos que devem compor a sua dieta e a de qualquer pessoa. Existem determinados alimentos que são, de modo implacável, deixados em segundo e terceiro planos quando se pensa em legumes e frutas. Curiosamente, a maioria sequer é conhecida do paladar dos brasileiros. Mas, sempre é bom descobrir novos aromas e se surpreender. Às vezes surge um ingrediente com aparência ou nome estranho, mas mesmo assim vale a pena seguir em frente e experimentá-los, pois todos a seguir são extremamente nutritivos e preciosos sob diversos aspectos. Acompanhe mais detalhas na sequência. A lentilha Muito consumida durante o período de comemorações do fim de ano, a lentilha está longe de ser a preferência nacional. No entanto, não deveria ser assim. As lentilhas mereceriam outro tratamento, já que são fundamentais para o enrijecimento dos músculos, além de conter substâncias que prestam auxílio durante os processos de cicatrização de ferimentos. Por fim, sua relevância também se deve ao fato de ser uma ótima fonte de ferro e fibras. Em virtude de tudo isso, é altamente aconselhável trocar, de vez em quando, o tradicional feijão pela lentilha. A batata doce Há quem goste, mas a grande maioria dispensa a batata doce. Os nutricionistas não negam que em comparação com a dita “batata comum” a versão doce detém uma concentração bem superior de calorias, o dobro para ser exato. Entretanto, eles recomendam o seu consumo devido ao conjunto de elementos que a constituem, tais como o potássio, as fibras e a vitamina C, diferentemente do que é apresentado pela outra batata. O inhame Como possui uma elevada concentração de proteínas, fósforo e potássio, o inhame é um dos alimentos que não podem faltar na lista, pois ajuda a evitar complicações oriundas de cálculos renais, osteoporose e artrite. Esse tubérculo também aparece bastante em massas, pães e cereais. Isso se torna possível porque ele é muito rico em fibras e carboidratos. Para obter todos esses nutrientes da forma correta, o melhor é consumir o inhame após ele passar por cozimento. Contudo, os nutricionistas avisam que eles não devem permanecer por muito tempo sob ação do fogo, pois isso favorece a perda de suas principais propriedades. O rabanete Por ser uma ótima fonte de diversos nutrientes, tais como fósforo, potássio, cálcio e magnésio, esse legume concede força extra ao sistema imunológico, melhora o trânsito do sistema respiratório e ainda aperfeiçoa as funções executadas dentro do aparelho digestivo. A nêspera O nome exótico costuma produzir caretas quando é pronunciado. Entretanto, trata-se da popular ameixa amarela, uma fruta que contém elevada concentração de cálcio, sais minerais, fósforo e vitamina C. Além de prestar uma valiosa colaboração para se evitar o desenvolvimento do diabetes, a nêspera também atua diretamente sobre as vias respiratórias, contribuindo para uma sensível melhora nos quadros de sinusite, asma, rinite e até bronquite. Esse efeito ocorre em razão de uma substância chamada triterpenos, capaz de sintetizar óxido nítrico. A beterraba Já esse legume não é tão raro assim na mesa dos brasileiros, pois possui muitos apreciadores. Mesmo assim, está um pouco distante de ser unanimidade. Esse pensamento deve mudar porque a beterraba desempenha um importante papel em relação ao consumo de oxigênio. Essa característica faz com que o corpo não sofra as consequências ocasionadas pela fadiga. Isso ficou comprovado mediante estudos científicos efetuados pelos cientistas britânicos da Universidade de Exeter. O nabo O nabo, por sua vez, é rico em potássio e cálcio, além das vitaminas A, B e C. Some-se a isso a sua contribuição sobre o fluxo do intestino e a ajuda quanto à prevenção de determinados cânceres. A chicória Como é composta por oligossacarídeos (carboidratos constituídos por até 6 monossacarídeos), o consumo da chicória se justifica pela provisão alimentar que é direcionada às bactérias que sobrevivem no intestino, os populares prebióticos. A presença destes no intestino é de suma importância, uma vez que eles ajudam a aliviar o fluxo do órgão ao mesmo tempo em que eliminam toxinas extremamente agressivas. Os nutricionistas também recomendam a ingestão regular de chicória porque essa planta gerencia os teores de triglicérides na corrente sanguínea, além de melhorar a rapidez de absorção dos sais minerais por parte do organismo. Por fim, a chicória também possui elevadas doses das vitaminas A, B, C e D e detém um baixíssimo nível de calorias. fonte : http://saudeemalta.net.br

Inesquecíveis Sylvia Telles e Luiz Bonfá

Eu vi, a água do rio correr, canoa do Nego passar, a chuva no vento chegar, eu vi sem poder reclamar.. “Cendi” meu cigarro e fumei, lembrei meu passado e chorei, peguei na viola e pontiei, tirei um cochilo e sonhei… Sonhei com você junto a mim, olhando meu rosto a sorrir, que grande alegria senti em ve-lo ao meu lado cantar.. Fiquei em silêncio a ouvir, seu canto saudoso chamar. Seus lábios tão doces beijei, do sonho bonito acordei… (“Meu sonho” – Luiz Bonfá e Sylvia Telles – )

How We Could Actually Build a Space Colony

In our cosmic megastructures series, Popular Mechanics explores some of the key engineering and design challenges in constructing gigantic structures for use by humankind in space. Today, three classic space-colony concepts.  Name: Bernal sphere; Stanford torus; O'Neill cylinder   Named For: Respectively, British scientist John Desmond Bernal, who proposed the idea in 1929; a summer study program held by NASA in 1975 at Stanford University; Princeton physicist Gerard K. O'Neill in a 1976 book on space colonization. Selected Science Fiction Portrayals: Stanford torus–like space stations are depicted in the 1968 film 2001: A Space Odyssey and 2013's Elysium. A modified O'Neill cylinder served as the basis of the Babylon 5 space station in the 1990s TV series of the same name, and in Arthur C. Clarke's Rama novels. The desire to live in new places has driven our species to settle Earth's harshest climes, from deserts to tundras. Someday, that same urge (or, less optimistically, devastation to our home world) might drive us to colonize the toughest environment of all: space. Although they sound unfathomably futuristic, space stations housing many thousands of people are actually well within our technical and engineering know-how. Scientists have argued that permanent space outposts conceivably could be built for less than what the United States spends annually on its military. Back in the 1970s, for example, NASA-funded researchers investigated the feasibility of multiple colony designs. And they had to do it for less than $35 billion (north of $200 billion in today's dollars). "Everything had to be based on what was available at the time," said Jerry Stone, leader of the British Interplanetary Society's Project SPACE (Study Project Advancing Colony Engineering), which is now updating the decades-old designs to take new materials such as carbon fiber into account, as well as modern robots and computing power. That 1970s workshop yielded three distinct design concepts that are still widely referenced today: the Bernal sphere, the Stanford torus, and the O'Neill cylinder. So we'll use them as our guide to what it would take to build a thriving colony in space. All three designs essentially contain a living space rotated to induce gravity, with the key difference being the shape used. The Bernal Sphere A Bernal sphere exterior. (Photo Credit: National Space Society) A Bernal sphere is essentially a globe about a third of a mile in diameter that rotates almost twice per minute to provide Earthlike gravity along its equator. (This feeling of artificial gravity would peter out near the poles.) Around 10,000 people could populate the interior space, their buildings lining the curve and appearing overhead clear across the sphere's expanse.   A Bernal sphere interior. (Photo Credit: Rick Guidice/NASA) The Stanford Torus A Stanford torus, a donut-shaped tube 430 feet thick with a diameter spanning 1.1 miles, spins once per minute to produce its gravity. The inner portion of the tube is open, as in the movie Elysium, or enclosed by a transparent material to let in light. The exterior of a Stanford torus. A mirror, situated above the torus, directs sunlight into the habitat ring. (Photo Credit: Don Davis/NASA) The torus would shelter a similar number of colonists as the sphere. Horizons would slope away, upwards, and the ring of the inhabited landscape soaring overhead would make newcomers swoon. Six spokes connect the habitat ring to a central hub where spacecraft can dock. A mass estimate: 10 million tons.   The interior of a Stanford torus. (Photo Credit: Don Davis/NASA) The O'Neill Cylinder The third shape is the O'Neill cylinder, the main body of which is about 5 miles wide and 20 miles long. Three strips of land would stretch along the interior, with three equal-size, interspersed strips serving as giant, sealed windows. The cylinder's huge size means a gentle spin of one revolution every minute and a half would be enough for terrestrial gravity. One problem, though, is that objects want to rotate about their long axes, so an active control system would be needed to maintain the desirable short-axis spin rate. O'Neill also envisioned that the cylinders would always come in counter-rotating pairs to offset destabilizing, gyroscopic effects that would cause the cylinders to stray from their intended, Sun-facing angles.   O'Neill cylinder interior. (Photo Credit: Rick Guidice/NASA) While any of these space colonies would be far more vast than humanity's biggest space infrastructure project to date, the International Space Station, their designs would not pose insurmountable engineering challenges. "From an engineering standpoint, the structure is very easy—the engineering calculations are totally valid," says Anders Sandberg, a research fellow at Oxford University's Future of Humanity Institute, who has studied megastructure concepts. Mining the Moon The bigger issue is the logistics. Rocketing enough material into space to build a colony would cost big bucks. A better bet: establishing simple manufacturing facilities in space designed to use raw materials mined from the moon or asteroids. The real cost-saver O'Neill envisioned would be installing a large electromagnetic catapult on the moon. Popular among hobbyists as coilguns, these devices use electromagnets to propel a magnetizable payload down a shaft. Thanks to the moon's weak gravity, only one-sixth of Earth's, throwing ample material into space would be a piece of cake. "The nice thing about an electromagnetic launcher, once it's been constructed, the launch costs are pretty much zero," Stone says. "You don't have to provide fuel, just electricity, and you get that from the sun by solar energy." The raw lunar or asteroidal ingredients could be fashioned molecule by molecule, thanks to 3D-printing technology, into most of the components needed for the colony. "We know from Apollo samples the composition of moon rocks and soil," Stone says. "There's lots of oxygen, which we need for breathing; lots of aluminum, which is needed for structural parts; there's silicon, for the windows; and magnesium and titanium and other useful stuff." Other key structural items would include solar panels for energy, and mirrors to angle reflected sunlight into habitat enclosures through their windows. Robots could handle much of the construction itself, guided by humans or working autonomously. Soil and other Earth-specific items, such as wildlife, would, with some difficulty, need to be shipped aloft. Colonies Built to Last The completed colonies would reside in the Lagrangian point known as L5, an island of stability where gravitational attraction from our planet, the moon, and the sun balance out. Dedicated agricultural areas (located in additional tori outside the Bernal sphere, or in the O'Neill cylinder's end caps, with optimized environmental controls) would keep colonists well-fed with fresh food. Trade with other colonies and Earth would supply any unavailable wares. To protect the colonies from meteorite impacts, leftover slag from manufacturing could be built up as padding on the colony's exterior. In general, the experts says, meteorites should be a manageable nuisance. "A meteorite with enough kinetic velocity to break a window panel might happen every three years," Stone says, based on studies of the issue. The windows would be made of many small panels, so one getting smashed now and then, no problem—it would take centuries for the colony's air to leak out. Shielding residents from harmful space radiation, though, is trickier. Cosmic rays from deep space could not reasonably be stopped if humans lived outside the protection of our planet's atmosphere. Space residents would have slightly elevated cancer risks, mitigable by frequent screenings, Stone says. As for radiation from the sun, several inches of water shielding would block most of it. During rarely intense solar flares, colonists could take refuge in thickly shielded "storm shelters"—not unlike precautions for major weather events here on Earth. One benefit: Space colonies would be immune to Earthly natural disasters. "In the colonies there would be no Marsquakers, no hurricanes, no tsunamis, no volcanoes," Stone says. "Plus, you pretty much control the weather in an O'Neill cylinder. Because it's so big, you would have natural rain clouds forming in there." That level of control—and the chance to thrive in the final frontier—should motivate humankind to leave our planetary home. As O'Neill wrote in Physics Today in 1974: "I believe we have now reached the point where we can, if we so choose, build new habitats far more comfortable, productive and attractive than is most of Earth."

O Professor Pardal ataca novamente.

Professor Sparrow strikes again…. Até agora eu conhecia como fontes geradoras de energia elétrica, a força do vento utilizada em geradores com imensas hélices e capazes de gerar uma potência da ordem de megawatts, outra que tem o maior potencial como fonte segura de geração de energia,  é a energia solar, e que ainda deve passar por várias etapas de desenvolvimento tecnológico,  em contraposição à energia nuclear que pode gerar uma potência enorme mas que apresenta os riscos já por demais conhecidos, a força gerada por usinas hidroelétricas e as baterias de lítio que estão cada vez mais eficientes. Recentemente eu tomei conhecimento de um gerador que utiliza a força das ondas do mar quando publiquei esse artigo, e compreendi rápidamente seu mecanismo de ação. O único ponto espinhoso nesse sistema é a necessidade de cabos para levar a corrente elétrica gerada até a praia ou costa oceânica, e isso talvez possa ser modificado no futuro. Talvez embarcações ancoradas próximas ao conjunto de bóias e providas de torres com cabos que levariam a energia gerada até à praia, Teria que haver uma fila dessas embarcações, e os cabos balançariam muito mas como elas estarão ancoradas no fundo do mar, isso não representaria problema.  Eu não sei a que distãncia da costa ficam essas bóias e se não ficarem muito distante, talvez no futuro torres fixadas no fundo do mar possam levar o cabo até a costa. Mas existe uma força natural que ainda não foi explorada, pelo menos não li até agora nada à respeito. Trata-se da força da gravidade. Se construirmos uma torre bem alta e no seu interior for fixado um tubo de metal, vertical, desde o topo até a metade da altura da torre, Dentro do tubo uma peça de metal com dentes em um dos seus lados, pesada o suficiente para fazer girar um alternador colocado no ponto central da torre, tendo uma polia também dentada para que a peça de metal engrene nessa polia e faça girar o alternador gerando assim uma corrente elétrica. Isso tudo é apenas o fundamento da minha idéia. Nesse ponto alguém perguntaria : E quando a barra de metal chegar ao chão como ela voltaria para o alto? Eu dei tratos á bola para descobrir uma maneira, e em pouco tempo cheguei à um resultado. No lugar da torre que evidentemente não funcionaria, uma roda. Como protótipo, uma roda de 6 metros de diâmetro, com um suporte fixado no chão, um alternador em seu centro e várias peças de metal denteada (umas 5 peças mais ou menos)  As peças de metal deslizariam em tubos como na torre, fazendo o alternador girar. Quando fossem chegando no lado oposto do raio da roda, um dispositivo faria com que esta girasse até o ponto em que a peça de metal subsequente começasse a deslizar, e ao  mesmo tempo engrenasse novamente com o alternador. Existe o problema da velocidade exigida pelo alternador para produzir uma voltagem. Isso poderia ser resolvido com uma caixa de engrenagens que aumentasse grandemente a velocidade. A peça de metal não iria então ser acoplada diretamente ao alternador, mas sim ao lado primário da caixa de engrenagens. No lado de saida iria ser acoplada o alternador já com a velocidade adequada. O alternador tem imãs em seus polos fazendo com que fique pesado para ser rotacionado. Isso é o que o peso da peça de metal descendo pelo tubo iria resolver. Tudo isso é apenas um esboço da idéia. Seria preciso calcular o peso que as peças de metal teriam que ter para que pudessem fazer girar o alternador, um que gerasse uma potência de 1200W, 120V e 10A, para uso doméstico. Muito teria que ser resolvido nesse projeto para que funcionasse, mas eu acredito que possa. E nem tenho idéia do tamanho que teria um alternador que produzisse a potência de 1200W, como também não tenho idéia do peso das peças de metal. Só mesmo engenheiros na área de eletricidade e mecânica poderiam dizer se essa minha engenhoca funcionaria. As imagens abaixo servem apenas para preencher o vazio, nada tendo a ver com o tema da postagem,mas valem a pena porque são imagens belíssimas. Se você não concordou com a minha idéia, tem as imagens abaixo para não dizer que perdeu tempo abrindo este post.