Imagem original (Wikipedia)
Depois de editada com o Gimp 2.6 . Agora ficou melhor, e não precisei eliminar detalhes. mas ainda não ficou perfeita, quem sabe na próxima.
Palmas para mim,(Obrigado 
)
terça-feira, 21 de outubro de 2014
SLC–Gateway Tower East
Imagem original (da Wikipedia) (Não estou criticando a Wikipedia, editar todas aquelas imagens seria impossível) A Wikipedia é ótima.
Depois de editada por mim com Gimp 2.6
Infelizmente, para se editar uma imagem assim, tem que se eliminar alguns detalhes. E mesmo assim não ficou perfeita. Só mesmo com Photoshop, talvez. Mas o Gimp é muito bom como editor, talvez me falte prática, creio que conseguiria deixar a imagem melhor e com os detalhes originais.
Esta é a primeira, vamos ver as subsequentes. 
User-friendly electronic 'Eyecane' enhances navigational abilities for blind
October 20, 2014
IOS Press BV
White Canes provide low-tech assistance to the visually impaired, but some blind people object to their use because they are cumbersome, fail to detect elevated obstacles, or require long training periods to master. Electronic travel aids (ETAs) have the potential to improve navigation for the blind, but early versions had disadvantages that limited widespread adoption. A new ETA, the "EyeCane," expands the world of its users, allowing them to better estimate distance, navigate their environment, and avoid obstacles, according to a new study
White Canes provide low-tech assistance to the visually impaired, but some blind people object to their use because they are cumbersome, fail to detect elevated obstacles, or require long training periods to master. Electronic travel aids (ETAs) have the potential to improve navigation for the blind, but early versions had disadvantages that limited widespread adoption. A new ETA, the "EyeCane," developed by a team of researchers at The Hebrew University of Jerusalem, expands the world of its users, allowing them to better estimate distance, navigate their environment, and avoid obstacles, according to a new study published in Restorative Neurology and Neuroscience.
"The EyeCane was designed to augment, or possibly in the more distant future, replace the traditional White Cane by adding information at greater distances (5 meters) and more angles, and most importantly by eliminating the need for contacts between the cane and the user's surroundings [which makes its use difficult] in cluttered or indoor environments," says Amir Amedi, PhD, Associate Professor of Medical Neurobiology at The Israel-Canada Institute for Medical Research, The Hebrew University of Jerusalem.
The EyeCane translates point-distance information into auditory and tactile cues. The device is able to provide the user with distance information simultaneously from two different directions: directly ahead for long distance perception and detection of waist-height obstacles and pointing downward at a 45° angle for ground-level assessment. The user scans a target with the device, the device emits a narrow beam with high spatial resolution toward the target, the beam hits the target and is returned to the device, and the device calculates the distance and translates it for the user interface. The user learns intuitively within a few minutes to decode the distance to the object via sound frequencies and/or vibration amplitudes.
Recent improvements have streamlined the device so its size is 4 x 6 x 12 centimeters with a weight of less than 100 grams. "This enables it to be easily held and pointed at different targets, while increasing battery life," says Prof. Amedi.
The authors conducted a series of experiments to evaluate the usefulness of the device for both blind and blindfolded sighted individuals. The aim of the first experiment was to see if the device could help in distance estimation. After less than five minutes of training, both blind and blindfolded individuals were able to estimate distance successfully almost 70% of the time, and the success rate surpassed 80% for two of the three blind participants. "It was amazing seeing how this additional distance changed their perception of their environment," notes Shachar Maidenbaum, one of the researchers on Prof. Amedi's team. "One user described it as if her hand was suddenly on the far side of the room, expanding her world."
A second experiment looked at whether the EyeCane could help individuals navigate an unfamiliar corridor by measuring the number of contacts with the walls. Those using a White Cane made an average of 28.2 contacts with the wall, compared to three contacts with the EyeCane -- a statistically significant tenfold reduction. A third experiment demonstrated that the EyeCane also helped users avoid chairs and other naturally occurring obstacles placed randomly in the surroundings.
"One of the key results we show here is that even after less than five minutes of training, participants were able to complete the tasks successfully," says Prof. Amedi. "This short training requirement is very significant, as it make the device much more user friendly. Every one of our blind users wanted to take the device home with them after the experiment, and felt they could immediately contribute to their everyday lives," adds Maidenbaum.
The Amedi lab is also involved in other projects for helping people who are blind. In another recent publication in Restorative Neurology and Neuroscience they introduced the EyeMusic, which offers much more information, but requires more intensive training. "We see the two technologies as complementar,y" says Prof. Amedi. "You would use the EyeMusic to recognize landmarks or an object and use the EyeCane to get to it safely while avoiding collisions."
A video demonstration of the EyeCane is available at http://www.youtube.com/watch?v=rpbGaPxUKb4. For more information visit the Amedi lab website at http://brain.huji.ac.il where you can also experience an online virtual demonstration of the device.
Story Source:
The above story is based on materials provided by IOS Press BV. Note: Materials may be edited for content and length.
Journal Reference:
- Shachar Maidenbaum, Shlomi Hanassy, Sami Abboud, Galit Buchs, Daniel-Robert Chebat, Shelly Levy-Tzedek, and Amir Amedi. The “EyeCane,” a new electronic travel aid for the blind: Technology, behavior & swift learning. Restorative Neurology and Neuroscience, October 2014 DOI: 10.3233/RNN-130351
Curitiba-PR-Brazil
Curitiba (Tupi: "Pine Nut Land",) is the capital and largest city of the Brazilian state of Paraná. The city's population numbered approximately 1,760,500 people as of 2010, making it the eighth most populous city in the country, and the largest in Brazil's South Region. The Curitiba Metropolitan area comprises 26 municipalities with a total population of over 3.2 million (IBGE estimate in 2010), making it the seventh most populous in the country.
Curitiba is an important cultural, political, and economic center in Latin America. The city sits on a plateau at 932 metres (3,058 ft) above sea level. It is located 105 kilometres (65 mi) west of the seaport of Paranaguá and is served by the Afonso Pena International and Bacacheri airports. The city hosts the Federal University of Paraná, established in 1912.
In the 1700s Curitiba possessed a favorable location between cattle-breeding country and marketplaces, leading to a successful cattle trade and the city's first major expansion. Later, between 1850 and 1950, it grew due to logging and agricultural expansion in the Paraná State (first Araucaria logging, later mate and coffee cultivation and in the 1970s wheat, corn and soybean cultivation). In the 1850s waves of European immigrants arrived in Curitiba, mainly Germans, Italians, Poles and Ukrainians, contributing to the city's economic and cultural development.Nowadays, only smaller numbers of foreign immigrants arrive, primarily from Middle Eastern and other Latin American countries.
The biggest expansion occurred after the 1950s, with innovative urban planning that changed the population size from some hundreds of thousands to more than a million people. Curitiba's economy is based on industry and services and is the fourth largest in Brazil. Economic growth occurred in parallel to a substantial inward flow of Brazilians from other cities of the country, as approximately half of the city's population was not born in Curitiba.
Curitiba sports one of Brazil's highest Human Development Index readings at 0.856, and in 2010 was awarded the Global Sustainable City Award, given to cities and municipalities that excel in sustainable urban development. According to US magazine Reader's Digest, Curitiba is the best "Brazilian Big City" in which to live.
Shopping Estação 1
Arena da Baixada
Universidade Federal do Paraná
Boston-MA-USA
Boston is the capital and largest city of the Commonwealth of Massachusetts in the United States. Boston also serves as county seat of Suffolk County. The largest city in New England, the city proper, covering 48 square miles (124 km2), had an estimated population of 645,966 in 2014, making it the 24th largest city in the United States. The city is the anchor of a substantially larger metropolitan area called Greater Boston, home to 4.5 million people and the tenth-largest metropolitan area in the country. Greater Boston as a commuting region is home to 7.6 million people, making it the sixth-largest Combined Statistical Area in the United States.
One of the oldest cities in the United States, Boston was founded on the Shawmut Peninsula in 1630 by Puritan colonists from England. It was the scene of several key events of the American Revolution, such as the Boston Massacre, the Boston Tea Party, the Battle of Bunker Hill, and the Siege of Boston. Upon American independence from Great Britain, the city continued to be an important port and manufacturing hub, as well as a center for education and culture. Through land reclamation and municipal annexation, Boston has expanded beyond the original peninsula. Its rich history helps attract many tourists, with Faneuil Hall alone attracting over 20 million visitors. Boston's many "firsts" include the United States' first public school, Boston Latin School (1635), and first subway system (1897).
The area's many colleges and universities make Boston an international center of higher education and medicine, and the city is considered to be a world leader in innovation for a variety of reasons. Boston's economic base also includes finance, professional and business services, and government activities. The city has one of the highest costs of living in the United States, though it remains high on world livability rankings.
Boston Public Garden
Luca Galuzzi
What’s Your Favorite Vintage Gadget?
Share your nostalgia for a long-obsolete device with other Scientific American readers
October 15, 2014 By Larry Greenemeier
Atari 800 XL Rijeka P&P
Wikimedia Commons/Roberta F.
Few technologies of the past 25 years have had more of an impact on our lives than the cell phone. Twenty years ago, a friend offered to lend me hers because I was having car trouble. She was worried I would get stuck on the side of the highway on my way home from work with no way of calling for help. Such concern about being unable to communicate now seems quaint. Like many people, I’m rarely without my smartphone these days, and it does a whole lot more than call for roadside assistance.
Such progress makes me nostalgic for the gadgets of yesterday that once seemed so cutting edge: the Samsung Rogue SCH-U960 that first put the Internet in my pocket (sort of); the Handspring Visor that let me digitize all my contacts a decade earlier; and the Atari 800XL that introduced me to home computing in the early 1980s. I’m sure that firing up my old 8-bit Atari for a game of Karateka or Hardball! wouldn’t be as much fun as I remember it being when I was in middle school. Still, I think back to all of the hours spent in front of that computer with a certain fondness.
Scientific American would like to hear about any vintage gadgets you have lying around—a Sharp Wizard PDA, a Motorola StarTAC phone or even an Apple Newton, for example—and why you still have them. Share a couple of sentences in the box below describing how you used that particular device, and include a related photo. Please note that you must own the rights to any photos you submit.
See-through, one-atom-thick, carbon electrodes powerful tool to study brain disorders
Photograph of a 16-electrode transparent array. Inset, a closer view showing the electrode area. Fainted squares are the recording electrodes.
Researchers from the Perelman School of Medicine and School of Engineering at the University of Pennsylvania and The Children's Hospital of Philadelphia have used graphene -- a two-dimensional form of carbon only one atom thick -- to fabricate a new type of microelectrode that solves a major problem for investigators looking to understand the intricate circuitry of the brain.
Pinning down the details of how individual neural circuits operate in epilepsy and other neurological disorders requires real-time observation of their locations, firing patterns, and other factors, using high-resolution optical imaging and electrophysiological recording. But traditional metallic microelectrodes are opaque and block the clinician's view and create shadows that can obscure important details. In the past, researchers could obtain either high-resolution optical images or electrophysiological data, but not both at the same time.
The Center for NeuroEngineering and Therapeutics (CNT), under the leadership of senior author Brian Litt, PhD, has solved this problem with the development of a completely transparent graphene microelectrode that allows for simultaneous optical imaging and electrophysiological recordings of neural circuits. Their work was published this week in Nature Communications.
"There are technologies that can give very high spatial resolution such as calcium imaging; there are technologies that can give high temporal resolution, such as electrophysiology, but there's no single technology that can provide both," says study co-first-author Duygu Kuzum, PhD. Along with co-author Hajime Takano, PhD, and their colleagues, Kuzum notes that the team developed a neuroelectrode technology based on graphene to achieve high spatial and temporal resolution simultaneously.
Aside from the obvious benefits of its transparency, graphene offers other advantages: "It can act as an anti-corrosive for metal surfaces to eliminate all corrosive electrochemical reactions in tissues," Kuzum says. "It's also inherently a low-noise material, which is important in neural recording because we try to get a high signal-to-noise ratio."
While previous efforts have been made to construct transparent electrodes using indium tin oxide, they are expensive and highly brittle, making that substance ill-suited for microelectrode arrays. "Another advantage of graphene is that it's flexible, so we can make very thin, flexible electrodes that can hug the neural tissue," Kuzum notes.
In the study, Litt, Kuzum, and their colleagues performed calcium imaging of hippocampal slices in a rat model with both confocal and two-photon microscopy, while also conducting electrophysiological recordings. On an individual cell level, they were able to observe temporal details of seizures and seizure-like activity with very high resolution. The team also notes that the single-electrode techniques used in the Nature Communications study could be easily adapted to study other larger areas of the brain with more expansive arrays.
The graphene microelectrodes developed could have wider application. "They can be used in any application that we need to record electrical signals, such as cardiac pacemakers or peripheral nervous system stimulators," says Kuzum. Because of graphene's nonmagnetic and anti-corrosive properties, these probes "can also be a very promising technology to increase the longevity of neural implants." Graphene's nonmagnetic characteristics also allow for safe, artifact-free MRI reading, unlike metallic implants.
Kuzum emphasizes that the transparent graphene microelectrode technology was achieved through an interdisciplinary effort of CNT and the departments of Neuroscience, Pediatrics, and Materials Science at Penn and the division of Neurology at CHOP.
Ertugrul Cubukcu's lab at Materials Science and Engineering Department helped with the graphene processing technology used in fabricating flexible transparent neural electrodes, as well as performing optical and materials characterization in collaboration with Euijae Shim and Jason Reed. The simultaneous imaging and recording experiments involving calcium imaging with confocal and two photon microscopy was performed at Douglas Coulter's Lab at CHOP with Hajime Takano. In vivo recording experiments were performed in collaboration with Halvor Juul in Marc Dichter's Lab. Somatasensory stimulation response experiments were done in collaboration with Timothy Lucas's Lab, Julius De Vries, and Andrew Richardson.
As the technology is further developed and used, Kuzum and her colleagues expect to gain greater insight into how the physiology of the brain can go awry. "It can provide information on neural circuits, which wasn't available before, because we didn't have the technology to probe them," she says. That information may include the identification of specific marker waveforms of brain electrical activity that can be mapped spatially and temporally to individual neural circuits. "We can also look at other neurological disorders and try to understand the correlation between different neural circuits using this technique," she says.
The work was supported by grants from the National Institutes of Health (R01-NS063039, 1U24 NS 63930-01A1, R01-NS038572, RO1-NS082046), Citizens United for Research in Epilepsy (CURE) through the Julie's Hope Award, and the Mirowski Family Foundation.
See-through sensors open new window into the brain
A blue light shines through a clear implantable medical sensor onto a brain model. See-through sensors, which have been developed by a team of UW-Madison engineers, should help neural researchers better view brain activity.
Developing invisible implantable medical sensor arrays, a team of University of Wisconsin-Madison engineers has overcome a major technological hurdle in researchers' efforts to understand the brain.
The team described its technology, which has applications in fields ranging from neuroscience to cardiac care and even contact lenses, in the Oct. 20 issue of the online journal Nature Communications.
Neural researchers study, monitor or stimulate the brain using imaging techniques in conjunction with implantable sensors that allow them to continuously capture and associate fleeting brain signals with the brain activity they can see. However, it's difficult to see brain activity when there are sensors blocking the view.
"One of the holy grails of neural implant technology is that we'd really like to have an implant device that doesn't interfere with any of the traditional imaging diagnostics," says Justin Williams, a professor of biomedical engineering and neurological surgery at UW-Madison. "A traditional implant looks like a square of dots, and you can't see anything under it. We wanted to make a transparent electronic device."
The researchers chose graphene, a material gaining wider use in everything from solar cells to electronics, because of its versatility and biocompatibility. And in fact, they can make their sensors incredibly flexible and transparent because the electronic circuit elements are only 4 atoms thick -- an astounding thinness made possible by graphene's excellent conductive properties. "It's got to be very thin and robust to survive in the body," says Zhenqiang (Jack) Ma, a professor of electrical and computer engineering at UW-Madison. "It is soft and flexible, and a good tradeoff between transparency, strength and conductivity."
Drawing on his expertise in developing revolutionary flexible electronics, he, Williams and their students designed and fabricated the microelectrode arrays, which -- unlike existing devices -- work in tandem with a range of imaging technologies. "Other implantable microdevices might be transparent at one wavelength, but not at others, or they lose their properties," says Ma. "Our devices are transparent across a large spectrum -- all the way from ultraviolet to deep infrared. We've even implanted them and you cannot find them in an MR scan."
The transparent sensors could be a boon to neuromodulation therapies, which physicians increasingly are using to control symptoms, restore function, and relieve pain in patients with diseases or disorders such as hypertension, epilepsy, Parkinson's disease, or others, says Kip Ludwig, a program director for the National Institutes of Health neural engineering research efforts. "Despite remarkable improvements seen in neuromodulation clinical trials for such diseases, our understanding of how these therapies work -- and therefore our ability to improve existing or identify new therapies -- is rudimentary."
Currently, he says, researchers are limited in their ability to directly observe how the body generates electrical signals, as well as how it reacts to externally generated electrical signals. "Clear electrodes in combination with recent technological advances in optogenetics and optical voltage probes will enable researchers to isolate those biological mechanisms. This fundamental knowledge could be catalytic in dramatically improving existing neuromodulation therapies and identifying new therapies."
The advance aligns with bold goals set forth in President Barack Obama's BRAIN (Brain Research through Advancing Innovative Neurotechnologies) Initiative. Obama announced the initiative in April 2013 as an effort to spur innovations that can revolutionize understanding of the brain and unlock ways to prevent, treat or cure such disorders as Alzheimer's and Parkinson's disease, post-traumatic stress disorder, epilepsy, traumatic brain injury, and others.
While the team centered its efforts on neural research, they already have started to explore other medical device applications. For example, working with researchers at the University of Illinois-Chicago, they prototyped a contact lens instrumented with dozens of invisible sensors to detect injury to the retina; the UIC team is exploring applications such as early diagnosis of glaucoma.
Additional authors on the Nature Communications paper include UW-Madison electrical and computer engineering graduate students Dong-Wook Park and Solomon Mikael, materials science graduate student Amelia A. Schendel, biomedical engineering research specialist Sarah K. Brodnick; biomedical engineering graduate students Thomas J. Richner, Jared P. Ness and Mohammed R. Hayat; collaborators Farid Atry, Seth T. Frye and Ramin Pashaie of the University of Wisconsin-Milwaukee; and Sanitta Thongpang of Mahidol University in Bangkok, Thailand.
The researchers are patenting their technology through the Wisconsin Alumni Research Foundation. Funding for the research came from the U.S. Defense Advanced Research Projects Agency, the National Institutes of Health, and the U.S. Office of Naval Research.
Story Source:
The above story is based on materials provided by University of Wisconsin-Madison. The original article was written by Renee Meiller. Note: Materials may be edited for content and length.
Journal Reference:
- Dong-Wook Park, Amelia A. Schendel, Solomon Mikael, Sarah K. Brodnick, Thomas J. Richner, Jared P. Ness, Mohammed R. Hayat, Farid Atry, Seth T. Frye, Ramin Pashaie, Sanitta Thongpang, Zhenqiang Ma, Justin C. Williams. Graphene-based carbon-layered electrode array technology for neural imaging and optogenetic applications. Nature Communications, 2014; 5: 5258 DOI: 10.1038/ncomms6258
University of Wisconsin-Madison. "See-through sensors open new window into the brain." ScienceDaily. ScienceDaily, 20 October 2014. <www.sciencedaily.com/releases/2014/10/141020212345.htm>.
Untangling the biological effects of blue light
Drs. Aguirre and Brainard and graduate student Spitschan found that melanopsin, a protein and short wave-sensitive S-cones, both in the retina have opposite effects and compete for control of the pupil in response to blue light.
Blue light can both set the mood and set in motion important biological responses. Researchers at the University of Pennsylvania's School of Medicine and School of Arts and Sciences have teased apart the separate biological responses of the human eye to blue light, revealing an unexpected contest for control. Their work addresses the properties of melanopsin, a light-sensitive protein in the eye that establishes the rhythm of our day-night cycle and the familiar constriction of the pupil to bright light. They measured the pupil response to stimulation of melanopsin and of short-wave-sensitive (S) cones, the other blue light-sensing cells that operate in daylight. Surprisingly, they found that melanopsin and S-cones have opposite effects and compete for control of the pupil in blue light. Their complete results are published in the current issue of PNAS.
Drs. Aguirre and Brainard and graduate student Spitschan found that melanopsin, a protein and short wave-sensitive S-cones, both in the retina have opposite effects and compete for control of the pupil in response to blue light.
"The challenge of studying melanopsin is that it is very sensitive to blue light, a short-wave light emitted by digital devices including smartphones, tablets, and computers, as are S-cones," says lead author, Manuel Spitschan, a Penn graduate student in psychology. "Previous studies in the human eye have not separately studied the S-cones and melanopsin because flashing a blue light stimulates both of these cells, so we didn't know if what a person saw or the response of the pupil was from one or both." To overcome this problem, the Penn team developed a special class of visual stimuli: they produced flickering light that stimulates melanopsin but is invisible to S-cones, and a second flickering light that stimulates S-cones but is invisible to melanopsin. The lights were created using a machine that can sculpt and switch between computer-designed rainbows of light.
The researchers had 16 people watch this flickering light while the response of their pupil was recorded. The light that stimulates melanopsin made the pupil slowly contract. To their surprise, they also discovered that stimulation of S-cones made the pupil get larger. That is, when the S-cones of the eye captured more light, the pupil enlarged, the opposite of what is generally thought of as the natural pupil response. This means that blue light sets off a tug-of-war between melanopsin and S-cones to make your pupil smaller or bigger. The melanopsin effect is stronger, resulting in the familiar shrinking of the pupil to bright light of any color.
"For the first time in people we are able to probe the relationship between melanopsin signals and the cones and how they work together or in opposition," says David Brainard, PhD, RRL professor of Psychology, director of the Vision Research Center and director of the Institute for Research in Cognitive Science. And what do these special flickering lights look like? "The flicker that stimulates S-cones looks like it is switching between a bluish and yellowish color. The flicker that stimulates melanopsin, however, is hard to see, and looks like a soft glow that rises and falls in brightness."
Light enters the human eye and is imaged on the retina. It has long been know that the retinal image is sensed by neurons known as the rods and cones. The rods operate in dim light levels and allow us to see at night. It is the signals from rods and cones that the brain converts into the images we see. Recently, though, another class of retinal cells has been identified that also senses light. These cells are known as intrinsically photosensitive ganglion cells, and they contain the protein melanopsin. Melanopsin is sensitive to light at wavelengths intermediate to those sensed by the S and M cones. It appears that it primarily mediates light-driven functions other than conscious vision, such as setting our circadian clock and contributing to control of the pupil.
The work of the Penn team makes it possible to isolate and study the properties of melanopsin in people, separate from the cone cells. We can now ask what we "see" with melanopsin.
"This is important because we think melanopsin could be involved in clinical conditions," says Geoffrey K. Aguirre, MD, PhD, a behavioral neurologist and associate professor in the department of Neurology. "For example, it seems that too much stimulation of melanopsin produces the feeling of pain from light that is too bright, and not having enough melanopsin stimulation may be part of seasonal affective disorder, in which people become depressed when they don't have enough light exposure. Having now teased apart the melanopsin and cone responses to blue light, we can study how the eye is involved in these disorders."
A patent on this alternative photoreceptor isolation method and its applications has been filed by the University of Pennsylvania with Spitschan, Aguirre and Brainard as inventors. In addition, they have founded a company with the Penn UpStart incubator with the goal to commercialize a device based upon these techniques. This work was supported by NIH grants R01 EY020516, R01 EY10016 and P30 EY001583.
Story Source:
The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.
Journal Reference:
- M. Spitschan, S. Jain, D. H. Brainard, G. K. Aguirre. Opponent melanopsin and S-cone signals in the human pupillary light response. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1400942111
Mental rest and reflection boost learning, study suggests
The patterns of brain activity recorded in this fMRI scanner revealed how mental rest and reflection on past learning activities can boost future learning.
A new study, which may have implications for approaches to education, finds that brain mechanisms engaged when people allow their minds to rest and reflect on things they've learned before, may boost later learning.
Scientists have already established that resting the mind, as in daydreaming, helps strengthen memories of events and retention of information. In a new twist, researchers at The University of Texas at Austin have shown that the right kind of mental rest, which strengthens and consolidates memories from recent learning tasks, helps boost future learning.
The results appear online this week in the journal Proceedings of the National Academy of Sciences.
Margaret Schlichting, a graduate student researcher, and Alison Preston, an associate professor of psychology and neuroscience, gave participants in the study two learning tasks in which participants were asked to memorize different series of associated photo pairs. Between the tasks, participants rested and could think about anything they chose, but brain scans found that the ones who used that time to reflect on what they had learned earlier in the day fared better on tests pertaining to what they learned later, especially where small threads of information between the two tasks overlapped. Participants seemed to be making connections that helped them absorb information later on, even if it was only loosely related to something they learned before.
"We've shown for the first time that how the brain processes information during rest can improve future learning," says Preston. "We think replaying memories during rest makes those earlier memories stronger, not just impacting the original content, but impacting the memories to come.
Until now, many scientists assumed that prior memories are more likely to interfere with new learning. This new study shows that at least in some situations, the opposite is true.
"Nothing happens in isolation," says Preston. "When you are learning something new, you bring to mind all of the things you know that are related to that new information. In doing so, you embed the new information into your existing knowledge."
Preston described how this new understanding might help teachers design more effective ways of teaching. Imagine a college professor is teaching students about how neurons communicate in the human brain, a process that shares some common features with an electric power grid. The professor might first cue the students to remember things they learned in a high school physics class about how electricity is conducted by wires.
"A professor might first get them thinking about the properties of electricity," says Preston. "Not necessarily in lecture form, but by asking questions to get students to recall what they already know. Then, the professor might begin the lecture on neuronal communication. By prompting them beforehand, the professor might help them reactivate relevant knowledge and make the new material more digestible for them."
This research was conducted with adult participants. The researchers will next study whether a similar dynamic is at work with children.
This work was supported by the National Institute of Mental Health of the National Institutes of Health, the National Science Foundation (NSF) through the NSF CAREER Award and the Department of Defense through the National Defense Science and Engineering Graduate Fellowship Program.
Story Source:
The above story is based on materials provided by University of Texas at Austin. Note: Materials may be edited for content and length.
Journal Reference:
- M. L. Schlichting, A. R. Preston. Memory reactivation during rest supports upcoming learning of related content. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1404396111
Salmonella-infected mice that were given antibiotics became superspreaders
Pigs. About 80 percent of all antibiotics used in the United States are given to livestock -- mainly cattle, pigs and chickens -- because doing so increases the animals' growth rates. Ten to thirty percent -- superspreaders -- remain symptom-free yet shed huge amounts of bacteria, causing the great bulk of the pathogen's spread through a population.
Salmonella-infected mice that were given antibiotics became sicker and began shedding far more bacteria in their feces than they had before.
Some people infected with pathogens spread their germs to others while remaining symptom-free themselves. Now, investigators at the Stanford University School of Medicine believe they may know why.
When the scientists gave oral antibiotics to mice infected with Salmonella typhimurium, a bacterial cause of food poisoning, a small minority -- so called "superspreaders" that had been shedding high numbers of salmonella in their feces for weeks -- remained healthy; they were unaffected by either the disease or the antibiotic. The rest of the mice got sicker instead of better and, oddly, started shedding like superspreaders. The findings point to a reason for superspreaders' ability to remain asymptomatic. They also pose ominous questions about the widespread, routine use of sub-therapeutic doses of antibiotics in livestock.
About 80 percent of all antibiotics used in the United States are given to livestock -- mainly cattle, pigs and chickens -- because doing so increases the animals' growth rates. Experts have already voiced concerns about how this practice contributes to the rise of drug-resistant pathogens. But the new study, published online Oct. 20 in Proceedings of the National Academy of Sciences, highlights an entirely different concern.
"We've shown that the immune state of an infected mouse given antibiotics can dictate how sick that mouse gets and also carries implications for disease transmission," said Denise Monack, PhD, associate professor of microbiology and immunology and the study's senior author. "If this holds true for livestock as well -- and I think it will -- it would have obvious public health implications. We need to think about the possibility that we're not only selecting for antibiotic-resistant microbes, but also impairing the health of our livestock and increasing the spread of contagious pathogens among them and us."
Upon invading the gut, S. typhimurium produces a powerful inflammation-inducing endotoxin, which annually results in an estimated 1 million cases of food poisoning, 19,000 hospitalizations and nearly 400 deaths in the United States. Passed from one individual to the next via fecal-oral transmission, it is known to produce a curious pattern of pathology among infected individuals: Some 70-90 percent of those infected shed fairly light amounts of bacteria (and so are not very contagious). But the remaining 10-30 percent -- superspreaders -- remain symptom-free yet shed huge amounts of bacteria, causing the great bulk of the pathogen's spread through a population. The reasons for this dichotomy have not been understood.
Evading detection
From a public health standpoint, knowing how to easily and quickly identify superspreaders could help curtail or even prevent epidemics, Monack said. Yet superspreaders don't appear to be sick, so they evade treatment. At the moment, the only way to determine which category a person or beast belongs to is by inspecting each individual's stool, a procedure that would be inconvenient at best even with livestock.
But the Stanford team has discovered that the immune systems of superspreaders and non-superspreaders are in differing states, raising the possibility of a blood test that could make identifying superspreaders more practical.
Salmonella infection in mice is not uncommon, said Monack. "Mice in a barn can be infected with salmonella for a long time and not get sick. They run around perfectly healthy. They're happy little incubators for salmonella."
In Monack's lab, more than 1 in 5 salmonella-infected mice are superspreaders. "The mice we use are inbred," she noted. "So this difference in response to salmonella infection can't be just a simple matter of genetic mutations."
The Stanford investigators had previously published work showing that giving non-superspreader mice an oral antibiotic, which kills some of the friendly microbes that ordinarily inhabit mammals' intestines and provide protection against invading pathogens, led to a rapid increase in salmonella shed in their feces.
In the new study, the scientists gave streptomycin, an antibiotic, to salmonella-infected mice. They were surprised by the results. Overnight, the majority that had been shedding relatively low levels of salmonella in their feces now evidenced very high levels of the pathogen in both their gut and their feces. And within a few days, these antibiotic-treated, formerly low-shedding mice became visibly ill. "They lost weight, had ruffled fur and hunched up the in corners of their cages," Monack said. "They also began to shed much larger quantities of bacteria." Several of them died. What was most surprising, though, was that superspreaders kept on shedding large amounts of bacteria while remaining blithely asymptomatic. Examination of the animals' intestines showed that gut concentrations of S. typhymurium in former non-superspreaders now rivaled those of superspreaders.
Giving the mice another antibiotic, neomycin, produced the same outcomes.
Symptom-free superspreaders
Postdoctoral scholar Smita Gopinath, PhD, the study's lead author, demonstrated that while all the animals harbored the pathogenic bacteria in their gut, the superspreaders -- despite carrying even higher intestinal levels of salmonella and harboring more gut inflammation than the other mice -- had a dampened immune response: Their overall systemic levels of several important pro-inflammatory signaling proteins, secreted by various types of immune cells to whip the immune system into an antimicrobial froth, were substantially lower than those of mice that had morphed from non-superspreaders to sickened superspreaders.
That explained the absence of symptoms in superspreaders, Monack said. Rather than mounting a heightened immune response to the pathogen, superspreaders appear to simply shrug off its presence. "Instead of jousting with the germ, they tolerate it," she said. "Their immune cells have been rewired and aren't responding to the inflammatory signals in the intestines the same way."
Antibiotics actually cause precisely the opposite of the intended effect in the salmonella-infected mouse population, Monack said. "The superspreaders stay healthy and keep on shedding and transmitting disease. Somehow, in an as yet unknown manner, they're coping with S. typhimurium. The others temporarily shed more bacteria than before, although they're too sick to spread much disease."
The bacteria shed in bulk by former non-superspreader mice were every bit as infectious and virulent as those shed by bona fide superspreaders.
Could it happen in humans?
The phenomenon shown in mice hasn't yet been shown in humans, but should be checked out, said Monack. "We humans shouldn't take antibiotics lightly," she said. "We need to consider whether they're always beneficial when they're given to animals across the board, or when we take them ourselves."
On the positive side, she said, "if we can figure out what leads to this immune dampening in superspreaders, it could potentially be helpful in suppressing symptoms of people with chronic inflammatory intestinal disorders, such as Crohn's syndrome or inflammatory bowel disease."
Other Stanford co-authors of the study are professor of comparative medicine Donna Bouley, DVM, PhD; assistant professor of chemical and systems biology Joshua Elias, PhD; and graduate student Joshua Lichtman.
The study was supported by the Burroughs Wellcome Fund and the National Institutes of Health (grant R01A1095396).
Story Source:
The above story is based on materials provided by Stanford University Medical Center. The original article was written by Bruce Goldman. Note: Materials may be edited for content and length.
Journal Reference:
- Smita Gopinath, Joshua S. Lichtman, Donna M. Bouley, Joshua E. Elias, and Denise M. Monack. Role of disease-associated tolerance in infectious superspreaders. PNAS, October 20, 2014 DOI: 10.1073/pnas.1409968111
Stanford University Medical Center. "Salmonella-infected mice that were given antibiotics became superspreaders." ScienceDaily. ScienceDaily, 20 October 2014. <www.sciencedaily.com/releases/2014/10/141020212928.htm>.
Carvey: The desktop 3D carving machine
Carvey is a prototype 3D carving device that can sculpt wood, plastic, and metal into almost any object that you care to design.
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3D printers are the appliance of choice for a new generation of makers keen to rapidly prototype straight from their computer. But many materials with which 3D printers can produce items have limitations, and there are others that they can’t work with at all. Enter Carvey – a working prototype of a desktop mounted, rapid-modelling, 3D carving device that can sculpt wood, plastic, and metal into almost any object that you care to design.
Inventables – the company behind the Carvey – claims that the benefits of being able to mill store-bought-quality items in minutes from a range of materials is the next, and obvious, step beyond 3D printing.
"In the past few years we’ve seen an explosion in 3D printing, and we believe that 3D carving is the next step," said Zach Kaplan, Inventables CEO. "We are looking for the support of the Kickstarter community to make Carvey a reality. Carvey is for the maker in all of us, and we hope we can bring everyone the opportunity to create something exciting."
With specifically-designed software dubbed "Easel" loaded on your computer, the Carvey is designed to be plug-and-play via USB. With the added benefit of automatic calibration, the system's developers also assert that it is simply a matter of plugging in the Carvey, designing your object, choosing the material that you want to be whittled, dropping in that material, and pushing "carve."
According to Inventables, you can mill all manner of things like circuit boards, aluminum, copper, brass, plastic, carbon fiber, hardwoods, softwoods ... in fact, a vast range of natural and man-made substances are said to be easy-carving grist to the Carvey's mill.
Carvey is also billed as whisper-quiet, despite the fact that it incorporates a high-speed, exceptionally sharp milling bit to do the cutting work. This is due to its noise-dampened aluminum housing, which the company says makes it suitable for use in quiet areas like classrooms or offices – it is even supposed to be possible to talk on the telephone right next to the unit whilst it is carving.
Now, CNC-style hobbyist milling machines are nothing new; there’s even one that can both mill and print in 3D. But the Carvey seems to embody a number of interesting and useful features that set it apart.
For a start, there’s the previously mentioned auto-calibration: many CNC machines require detailed and fiddly set up processes in this regard. Then there’s the idea that you can make a prototype, or even a limited production run, of items using durable and aesthetically-pleasing materials rather than just plastic.
"People want to create their own products out of different materials, but there is nothing available on the market as affordable and easy to use as Carvey," said Inventables Chief Engineer, Bart Dring. "We aim to make the process of making easier and more inspiring, in a way that considers the overall user experience - and we hope we’ve created this with Carvey."
To get the prototype to the engineering verification stage and to put prototypes into pilot production, the Carvey team have just launched a crowdfunding campaign on Kickstarter. With early-bird pledges US$1,999 or more, you can "pre-order" a Carvey complete with toolkit and starter bit. It's due to be shipped – providing all goes to plan – sometime in September 2015.
Sources: Inventables, Kickstarter
Yosemite National Park
Yosemite National Park is a United States National Park spanning eastern portions of Tuolumne, Mariposa and Madera counties in the central eastern portion of the U.S. state of California. The park, which is managed by the National Park Service, covers an area of 747,956 acres (3,026.87 km2) and reaches across the western slopes of the Sierra Nevada mountain chain. Over 3.7 million people visit Yosemite each year: most spend their time in the seven square miles (18 km2) of Yosemite Valley. Designated a World Heritage Site in 1984, Yosemite is internationally recognized for its spectacular granite cliffs, waterfalls, clear streams, Giant Sequoia groves, and biological diversity. Almost 95% of the park is designated wilderness. Yosemite was central to the development of the national park idea. First, Galen Clark and others lobbied to protect Yosemite Valley from development, ultimately leading to President Abraham Lincoln's signing the Yosemite Grant in 1864. Later, John Muir led a successful movement to establish a larger national park encompassing not just the valley, but surrounding mountains and forests as well—paving the way for the United States national park system.
Yosemite is one of the largest and least fragmented habitat blocks in the Sierra Nevada, and the park supports a diversity of plants and animals. The park has an elevation range from 2,127 to 13,114 feet (648 to 3,997 m) and contains five major vegetation zones: chaparral/oak woodland, lower montane forest, upper montane forest, subalpine zone, and alpine. Of California's 7,000 plant species, about 50% occur in the Sierra Nevada and more than 20% within Yosemite. There is suitable habitat or documentation for more than 160 rare plants in the park, with rare local geologic formations and unique soils characterizing the restricted ranges many of these plants occupy.
The geology of the Yosemite area is characterized by granitic rocks and remnants of older rock. About 10 million years ago, the Sierra Nevada was uplifted and then tilted to form its relatively gentle western slopes and the more dramatic eastern slopes. The uplift increased the steepness of stream and river beds, resulting in formation of deep, narrow canyons. About 1 million years ago, snow and ice accumulated, forming glaciers at the higher alpine meadows that moved down the river valleys. Ice thickness in Yosemite Valley may have reached 4,000 feet (1,200 m) during the early glacial episode. The downslope movement of the ice masses cut and sculpted the U-shaped valley that attracts so many visitors to its scenic vistas today.
Muir and Roosevelt (restored)
Nucla, Colorado
From Wikipedia, the free encyclopedia
Nucla is a Statutory Town in Montrose County, Colorado, United States. The population was 734 at the 2000 census. Its name comes from the town's founders intent that it serve as a "nucleus" for the surrounding farms and mines, although it has since come to be associated with the growth of uranium mining in the region.
Geography
Nucla is located at 38°16′0″N 108°32′50″W38.26667°N 108.54722°W / 38.26667; -108.54722 (38.266775, -108.547146).5
According to the United States Census Bureau, the town has a total area of 0.7 square miles (1.8 km2), all of it land. Nucla is located in an area of desert land, surrounding the Uncompahgre National Forest.
Demographics
As of the census6 of 2000, there were 734 people, 311 households, and 208 families residing in the town. The population density was 1,036.0 people per square mile (399.2/km²). There were 369 housing units at an average density of 520.8 per square mile (200.7/km²). The racial makeup of the town was 94.69% White, 1.09% Native American, 0.14% Asian, 0.54% from other races, and 3.54% from two or more races. Hispanic or Latino of any race were 3.68% of the population.
There were 311 households out of which 31.8% had children under the age of 18 living with them, 49.8% were married couples living together, 11.3% had a female householder with no husband present, and 32.8% were non-families. 30.5% of all households were made up of individuals and 14.8% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.91.
In the town the population was spread out with 28.6% under the age of 18, 6.5% from 18 to 24, 24.3% from 25 to 44, 27.9% from 45 to 64, and 12.7% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 93.7 males. For every 100 females age 18 and over, there were 89.9 males.
The median income for a household in the town was $28,466, and the median income for a family was $33,636. Males had a median income of $32,417 versus $21,726 for females. The per capita income for the town was $12,982. About 14.4% of families and 17.0% of the population were below the poverty line, including 23.4% of those under age 18 and 12.1% of those age 65 or over.
There are several prehistoric sites near Nucla on the Colorado State Register of Historic Properties:7
- Cottonwood Cave is a large rock shelter inhabited by 270 BC and the earliest date at which corn was found in the state of Colorado.
- Tabeguache Cave is another prehistoric rock shelter.
- Tabeguache Pueblo is an example of an early, dispersed Ancient Pueblo settlement, inhabited about AD 1100 and later abandoned.
The town was established by socialists, who emphasized the sharing of things. The name of the town comes from the word nucleus.
In May 2013, the Nucla Town Board passed an ordinance that required every non-exempted head of household in the town to own a firearm.
Notable residents
- W. A. Draves (1912–1994), founder and an apostle of the Church of Christ with the Elijah Message, now headquartered in Independence, Missouri. Draves is believed by his church to have received ninety messages from John the Baptist, some of them while he lived in Nucla.
- Bill Symons, Canadian Football Hall of Famer.
- Buzz Zatterstrom, Leonard Sage Zatterstrom, During his long life, he was an athlete, coach, teacher, rancher, craftsman, and artist.
Municipalities and communities of Montrose County, Colorado, United States
Strengthening Thin-Film Bonds with Ultrafast Data Collection
From NIST Tech Beat: October 17, 2014
Contact: Michael Baum
301-975-2763
When studying extremely fast reactions in ultrathin materials, two measurements are better than one. A new research tool invented by researchers at Lawrence Livermore National Laboratory (LLNL), Johns Hopkins University and the National Institute of Standards and Technology (NIST) captures information about both temperature and crystal structure during extremely fast reactions in thin-film materials.*
Temperature and structure: Graph shows heat absorbed by a thin film of aluminum as its temperature increased. Inset boxes show electron diffraction patterns captured by DTEM as temperature changes. The patterns reveal the crystal structure and orientation of the aluminum. At low temperatures, pattern is characteristic of a face-centered-cubic crystal structure. When the sample is heated past the large melting peak, the spots disappear indicating that the aluminum has lost its crystal structure due to melting.
Credit: NIST
The combined device will help scientists study new materials and processes used to make advanced technologies, including state-of-the-art semiconductors and flat-screen display devices, says David LaVan, a NIST materials scientist who co-led the study.
Modern electronics manufacturing often pushes the limits of current measurement technology. Making a flat-screen display requires bonding a large sheet of a pure, rare material to an underlying metal substrate with as few defects as possible. To do so, manufacturers typically sandwich a thin film between the two materials and heat it rapidly to high temperatures, causing it to react and bond the metals.
This method usually works, but industry researchers would like to optimize the process. And existing tools to describe what’s happening in the reactive thin film provide only incomplete information. One such technique, nanocalorimetry, can track very precisely large temperature changes—at rates up to ,1000 degrees Celsius per millisecond—that occur at a very small scale. Such a measurement can alert researchers to a material’s phase transitions, for example, when a metal melts. But nanocalorimetry tells researchers little about the actual chemical processes or microstructural changes they are measuring as a material heats up or cools down.
To study these changes, LaVan’s LLNL collaborators Geoffrey Campbell, Thomas LaGrange and Bryan Reed developed a different device, the dynamic transmission electron microscope (DTEM). In traditional transmission electron microscopy, diffraction and transmission patterns made by electrons passing through a thin sample provide information about how the sample’s atoms are arranged. But TEM typically requires that the sample maintain one crystal structure for an extended period, as the microscope’s detector captures enough electrons to generate an image.
DTEM, by contrast, captures structural information very rapidly. It relies on a pulsed laser to send short, bright blasts of electrons through a sample. LaVan and his colleagues at NIST and Johns Hopkins realized that if the LLNL group’s DTEM laser pulses were synched with a rapid temperature rise, the researchers could simultaneously track phase transitions and structural changes in materials they were studying. “It’s like peanut butter and chocolate,” LaVan says. “If we can somehow get these two instruments working simultaneously, we’ll have the whole story.”
But first the researchers needed to shrink the circuitry for their nanocalorimeter to a tenth of its original size, so that it could fit inside the microscope. The researchers also needed to write new software to synchronize the microscope’s electron pulses with the nanocalorimeter’s rapid heating pulses. “To get [the devices] to work together was really a substantial effort from three different research groups,” LaVan says.
Finally, LaVan and team member Michael Grapes, a research associate at NIST, and graduate student in materials science Timothy Weihs’ group at Johns Hopkins, flew the redesigned nanocalorimeter to Livermore, synchronized it with the DTEM, and ran tests on thin films of materials such as aluminum, whose microstructural and thermal properties are well understood. The scientists found that, as expected, the nanocalorimeter recorded phase transitions at the same time the DTEM recorded structural changes, and both sets of measurements were consistent with their study materials’ known properties.
The research team is already moving on to study other, less well-understood materials. Recently, the scientists have used their combined nanocalorimeter-DTEM to measure what happens when aluminum and nickel combine to form thin-film alloys. The team’s study provides, for the first time, simultaneous structural and thermal data on this reaction at high heating rates, LaVan says.
*M.D. Grapes, T. LaGrange, L.H. Friedman, B.W. Reed, G.H. Campbell ,T.P. Weihs and D.A. LaVan. Combining nanocalorimetry and dynamic transmission electron microscopy for in situ characterization of materials processes under rapid heating and cooling. Review of Scientific Instruments 85, 084902. Published online Aug. 18, 2014.
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