Πέμπτη, 24 Απριλίου 2014

ScienceDaily: Latest Science News

ScienceDaily: Latest Science News


Innovation improves drowsy driver detection

Posted: 23 Apr 2014 02:09 PM PDT

A new way to detect when drivers are about to nod off behind the wheel has been developed. "Video-based systems that use cameras to detect when a car is drifting out of its lane are cumbersome and expensive. They don't work well on snow-covered or curvy roads, in darkness or when lane markers are faded or missing. Our invention provides an inexpensive and user-friendly technology that overcomes these limitations and can help catch fatigue earlier, well before accidents are likely to happen," said a developer of the device.

Drought may take toll on Congo rainforest, NASA satellites show

Posted: 23 Apr 2014 02:09 PM PDT

A new analysis of NASA satellite data shows Africa's Congo rainforest, the second-largest tropical rainforest in the world, has undergone a large-scale decline in greenness over the past decade. Scientists use the satellite-derived "greenness" of forest regions as one indicator of a forest's health. While this study looks specifically at the impact of a persistent drought in the Congo region since 2000, researchers say that a continued drying trend might alter the composition and structure of the Congo rainforest, affecting its biodiversity and carbon storage.

Not just the poor live hand-to-mouth

Posted: 23 Apr 2014 02:09 PM PDT

Thirty to 40 percent of US households live hand-to-mouth, but new research has found that most of those people aren't poor. Stimulus programs -- such as those in 2001, 2008 and 2009 -- are designed to boost the economy quickly by getting cash into the hands of people likely to turn around and spend it. But sending cash to just the very poor may not be the right approach, according to researchers.

Rural microbes could boost city dwellers' health, study finds

Posted: 23 Apr 2014 02:09 PM PDT

The greater prevalence of asthma, allergies and other chronic inflammatory disorders among people of lower socioeconomic status might be due in part to their reduced exposure to the microbes that thrive in rural environments, according to a new scientific paper.

Cyber buddy is better than 'no buddy'

Posted: 23 Apr 2014 12:10 PM PDT

A researcher is looking to give exercise enthusiasts the extra nudge they need during a workout, and her latest research shows that a cyber buddy can help. The study is the first to indicate that although a human partner is still a better motivator during exercise, a software-generated partner also can be effective.

Male or female? First sex-determining genes appeared in mammals some 180 million years ago

Posted: 23 Apr 2014 12:10 PM PDT

The Y chromosome, which distinguishes males from females at the genetic level, appeared some 180 million years ago. It originated twice independently in all mammals. Scientists have managed to date these events that are crucial for both mammalian evolution and our lives, because the Y chromosome determines whether we are born as a boy or girl.

Superconducting qubit array points the way to quantum computers

Posted: 23 Apr 2014 12:10 PM PDT

A fully functional quantum computer is one of the holy grails of physics. Physicists have moved one step closer to making a quantum computer a reality by demonstrating a new level of reliability in a five-qubit array. Quantum computing is anything but simple. It relies on aspects of quantum mechanics such as superposition. This notion holds that any physical object, such as an atom or electron -- what quantum computers use to store information -- can exist in all of its theoretical states simultaneously. This could take parallel computing to new heights.

Mapping the road to quantum gravity

Posted: 23 Apr 2014 12:09 PM PDT

The road uniting quantum field theory and general relativity -- the two great theories of modern physics -- has been impassable for 80 years. Could a tool from condensed matter physics finally help map the way?

Atomic switcheroo explains origins of thin-film solar cell mystery

Posted: 23 Apr 2014 12:09 PM PDT

Treating cadmium-telluride (CdTe) solar cell materials with cadmium-chloride improves their efficiency, but researchers have not fully understood why.

Finding safe drugs to treat neurodegenerative diseases

Posted: 23 Apr 2014 11:30 AM PDT

'Mutant' protein clusters, long blamed for the progression of Huntington's and other neurodegenerative diseases, have been the primary focus of therapies in development by pharmaceutical companies. But according to new research, these drugs may not only be ineffective -- they may pose a serious threat to patients.

Conservation priorities released for several protected areas along U.S.-Mexico border

Posted: 23 Apr 2014 11:30 AM PDT

The CEC releases its conservation assessment for priority conservation areas in a region straddling the United States-Mexico border that includes 11 different protected areas in the states of Texas, Coahuila, and Chihuahua. This region features highly diverse arid and semi-arid habitats inhabited by endangered plants and animals, and provides a vital migratory stopping point for many species of birds and animals.

Increased infrastructure required for effective oil spill response in U.S. Arctic

Posted: 23 Apr 2014 11:30 AM PDT

A changing climate is increasing the accessibility of U.S. Arctic waters to commercial activities such as shipping, oil and gas development, and tourism, raising concern about the risk of oil spills. The Arctic poses several challenges to oil spill response, including extreme weather and environmental settings, limited operations and communications infrastructure, a vast geographic area, and vulnerable species, ecosystems, and cultures.

Hearing quality restored with bionic ear technology used for gene therapy: Re-growing auditory nerves

Posted: 23 Apr 2014 11:30 AM PDT

Researchers have for the first time used electrical pulses delivered from a cochlear implant to deliver gene therapy, thereby successfully regrowing auditory nerves. The research also heralds a possible new way of treating a range of neurological disorders, including Parkinson's disease, and psychiatric conditions such as depression through this novel way of delivering gene therapy.

Halving hydrogen: First view of nature-inspired catalyst after ripping hydrogen apart provides insights for better fuel cells

Posted: 23 Apr 2014 11:28 AM PDT

A fuel cell catalyst that converts hydrogen into electricity must tear open a hydrogen molecule. Now researchers have captured a view of such a catalyst holding onto the two halves of its hydrogen feast, provides insight into how to make the catalyst work better.

Pollutants from coal-burning stoves strongly associated with miscarriages in Mongolia

Posted: 23 Apr 2014 11:28 AM PDT

Burning coal for domestic heating may contribute to early fetal death according to a new study that took place in Ulaanbaatar, Mongolia -- the coldest capital city in the world. Researchers report "alarmingly strong statistical correlations" between seasonal ambient air pollutants and pregnancy loss.

Picky male black widow spiders prefer well-fed virgins

Posted: 23 Apr 2014 10:26 AM PDT

New research shows that male black widow spiders prefer their female mates to be well-fed virgins -- a rare example of mate preference by male spiders. The study found they can tell whether a potential mate is well-fed and unmated by pheromones released by females.

Enzymes that help fix cancer-causing DNA defects disovered

Posted: 23 Apr 2014 10:26 AM PDT

An important enzyme pathway that helps prevent new cells from receiving too many or too few chromosomes, a condition that has been directly linked to cancer and other diseases, has been discovered by researchers. Near the end of cell division, the enzyme Cdc14 activates Yen1, an enzyme that ensures any breaks in DNA are fully repaired before the parent cell distributes copies of the genome to daughter cells, the researchers found. This process helps safeguard against some of the most devastating genome errors, including the loss of chromosomes or chromosome segments.

Gold nanoparticles help target, quantify breast cancer segments in a living cell

Posted: 23 Apr 2014 10:26 AM PDT

A way to detect and measure cancer levels in a living cell by using tiny gold particles with tails of synthetic DNA has been developed by scientists. The process uses gold nanoparticles to target and bind to fragments of genetic material known as BRCA1 messenger RNA splice variants, which can indicate the presence and stage of breast cancer. The number of these mRNA splice variants in a cell can be determined by examining the specific signal that light produces when it interacts with the gold nanoparticles.

Novel compound halts cocaine addiction, relapse behaviors

Posted: 23 Apr 2014 10:26 AM PDT

A novel compound that targets an important brain receptor has a dramatic effect against a host of cocaine addiction behaviors, including relapse behavior, an animal study has found. The research provides strong evidence that this may be a novel lead compound for treating cocaine addiction, for which no effective medications exist.

Scientists identify source of mysterious sound in the Southern Ocean

Posted: 23 Apr 2014 10:26 AM PDT

Scientists have conclusive evidence that the source of a unique rhythmic sound, recorded for decades in the Southern Ocean and called the 'bio-duck,' is the Antarctic minke whale (Balaenoptera bonaerensis). First described and named by submarine personnel in the 1960s who thought it sounded like a duck, the bio-duck sound has been recorded at various locations in the Southern Ocean, but its source has remained a mystery, until now.

Odds of storm waters overflowing Manhattan seawall up 20-fold

Posted: 23 Apr 2014 10:26 AM PDT

Maximum water levels in New York harbor during major storms have risen by nearly two and a half feet since the mid-1800s, making the chances of water overtopping the Manhattan seawall now at least 20 times greater than they were 170 years ago, according to a new study.

Hundreds of genetic mutations found in healthy blood of a supercentenarian

Posted: 23 Apr 2014 10:26 AM PDT

Genetic mutations are commonly studied because of links to diseases such as cancer; however, little is known about mutations occurring in healthy individuals. Researchers have now detected over 400 mutations in healthy blood cells of a 115-year-old woman, suggesting that lesions at these sites are largely harmless over the course of a lifetime.

Predicting drift of floating pumice 'islands' can benefit shipping

Posted: 23 Apr 2014 10:25 AM PDT

A new technique will aid in predicting the dispersal and drift patterns of large floating 'islands' of pumice created by volcanic eruptions at sea. Known as pumice rafts, these large mobile accumulations of pumice fragments can spread to affect a considerable area of the ocean, damaging vessels and disrupting shipping routes for months or even years. The ability to predict where these rafts will end up could give enough advance warning for protective measures to be put in place on shipping routes or in harbours where the presence of pumice is hazardous.

Late freeze kills fruit buds, study shows

Posted: 23 Apr 2014 10:24 AM PDT

The recent late cold snap could mean less fruit this year. A horticulturist explains how to check if your fruit buds survived the late burst of cold weather. Fruit buds are usually damaged when it is 28 degrees Fahrenheit or lower. However, this researcher says that while the fruit may be lost, the trees will survive so there should be plenty of fruit next year.

Sugar-sweetened beverages contribute to U.S. obesity epidemic, particularly among children

Posted: 23 Apr 2014 10:24 AM PDT

In response to the ongoing policy discussions on the role of sugar-sweetened beverages (SSBs) on weight and health, The Obesity Society (TOS) concludes that SSBs contribute to the United States' obesity epidemic, particularly among children. Based on an in-depth analysis of the current research, TOS's position statement provides several recommendations for improving health, including that children minimize their consumption of SSBs.

Some astronauts at risk for cognitive impairment, animal studies suggest

Posted: 23 Apr 2014 10:24 AM PDT

Rats exposed to high-energy particles, simulating conditions astronauts would face on a long-term deep space mission, show lapses in attention and slower reaction times, even when the radiation exposure is in extremely low dose ranges, new research shows. The cognitive impairments — which affected a large subset, but far from all, of the animals — appear to be linked to protein changes in the brain, the scientists say.

New target for prostate cancer resistant to anti-hormone therapies

Posted: 23 Apr 2014 10:24 AM PDT

A new target that could remain sensitive even when prostate cancer becomes resistant to current treatments has been discovered by researchers. Prostate cancer becomes deadly when anti-hormone treatments stop working. This new study suggests a way to block the hormones at their entrance.

From liability to viability: Genes on the Y chromosome prove essential for male survival

Posted: 23 Apr 2014 10:24 AM PDT

The human Y chromosome has, over the course of millions of years of evolution, preserved a small set of genes that has ensured not only its own survival but also the survival of men. Moreover, the vast majority of these tenacious genes appear to have little if any role in sex determination or sperm production. Taken together, these remarkable findings suggest that because these Y-linked genes are active across the body, they may actually be contributing to differences in disease susceptibility and severity observed between men and women.

Following a protein's travel inside cells is key to improving patient monitoring, drug development

Posted: 23 Apr 2014 08:15 AM PDT

A technique to detect subcellular location of a protein has been developed by scientists. In science, "simple and accessible detection methods that can rapidly screen a large cell population with the resolution of a single cell inside that population has been seriously lacking," said one engineer involved in the study. Their work involved a simple and unique tweak to the conventional cell staining process allowed the researchers to accurately define the subcellular location of the protein by measuring the amount of the residual protein after release.

More Americans in their golden years are going hungry

Posted: 23 Apr 2014 08:15 AM PDT

The seniors who are dealing with hunger are also facing negative health and nutrition consequences, American research indicates. In a country as wealthy as the United States, it may come as a surprise that one in 12 seniors do not have access to adequate food due to lack of money or other financial resources. They are food insecure.

Airport security-style technology could help doctors decide on stroke treatment

Posted: 23 Apr 2014 08:15 AM PDT

A new computer program could help doctors predict which patients might suffer potentially fatal side-effects from a key stroke treatment. The program assesses brain scans using pattern recognition software similar to that used in airport security and passport control. Currently, stroke affects over 15 million people each year worldwide. Ischemic strokes are the most common and these occur when small clots interrupt the blood supply to the brain.

Surface area of the digestive tract much smaller than previously thought

Posted: 23 Apr 2014 08:15 AM PDT

The internal surface area of the gastro-intestinal tract has long been considered to be between 180 and 300 square meters. Scientists have used refined microscopic techniques that indicate a much smaller area. "Actually, the inner surface of the gastro-intestinal tract is only as large as a normal studio apartment," says one scientist.

Fiction prepares us for a world changed by global warming

Posted: 23 Apr 2014 07:27 AM PDT

Climate fiction, or simply cli-fi, is a newly coined term for novels and films which focus on the consequences of global warming. New research shows how these fictions serve as a mental laboratory that allows us to simulate the potential consequences of climate change and imagine other living conditions.

In lab tests, the antimicrobial ingredient triclosan spurs growth of breast cancer cells

Posted: 23 Apr 2014 07:27 AM PDT

Some manufacturers are turning away from using triclosan as an antimicrobial ingredient in soaps, toothpastes and other products over health concerns. And now scientists are reporting new evidence that appears to support these worries. Their study found that triclosan, as well as another commercial substance called octylphenol, promoted the growth of human breast cancer cells in lab dishes and breast cancer tumors in mice.

Legalizing medical marijuana doesn't increase use among adolescents, study says

Posted: 23 Apr 2014 07:27 AM PDT

Parents and physicians concerned about an increase in adolescents' marijuana use following the legalization of medical marijuana can breathe a sigh of relief. According to a new study that compared 20 years worth of data from states with and without medical marijuana laws, legalizing the drug did not lead to increased use among adolescents.

How to avoid water wars between 'fracking' industry and residents

Posted: 23 Apr 2014 07:27 AM PDT

The shale gas boom has transformed the energy landscape in the U.S., but in some drier locations, it could cause conflict among the energy industry, residents and agricultural interests over already-scarce water resources, say researchers. They add that degraded water quality is a potential risk unless there are adequate safeguards.

Steering chemical reactions with laser pulses

Posted: 23 Apr 2014 07:27 AM PDT

Ultra short laserpulses in the femtosecond-range give scientists a powerful new method of controlling chemical reactions. A team of researchers could now show that the fragmentation of carbohydrates can be controlled by these pulses.

Male-biased tweeting: Gender differences in the use of Twitter

Posted: 23 Apr 2014 07:27 AM PDT

Today women take an active part in public life. Without a doubt, they also converse with other women. In fact, they even talk to each other about other things besides men. As banal as it sounds, this is far from being the norm in Hollywood movies. The same goes for Twitter, as a new study shows.

Physical activity keeps hippocampus healthy in people at risk for Alzheimer's disease

Posted: 23 Apr 2014 07:27 AM PDT

Moderate physical activity may preserve the hippocampus -- the brain region responsible for memory and spatial orientation that is attacked first in Alzheimer's disease, a study of older adults at increased risk for Alzheimer's disease shows. It is the first evidence that physical activity may protect against cognitive decline and the onset of dementia symptoms in those who carry the genetic marker for Alzheimer's.

High-calorie, low-nutrient foods in kids' TV programs

Posted: 23 Apr 2014 07:26 AM PDT

Fruits and vegetables are often displayed in the popular Swedish children's TV show Bolibompa, but there are also plenty of high-sugar foods. A new study explores how food is portrayed in children's TV programs, as well as the link between young children's TV viewing, dietary habits and weight status.

Uniting community development efforts could benefit members of underserved communities

Posted: 23 Apr 2014 07:22 AM PDT

Although many organizations address poverty, they often serve similar demographics and may compete for clients and resources. Recently, researchers studied one effort to link community development organizations and concluded that this program is the hub that can improve resource access for members of underserved communities.

Toward unraveling the Alzheimer's mystery: New step points to proteins

Posted: 23 Apr 2014 07:21 AM PDT

Getting to the bottom of Alzheimer's disease has been a rapidly evolving pursuit with many twists, turns and controversies. In the latest crook in the research road, scientists have found a new insight into the interaction between proteins associated with the disease. The report could have important implications for developing novel treatments.

ADHD drug may help preserve self-control resources

Posted: 23 Apr 2014 07:21 AM PDT

Methylphenidate, also known as Ritalin, may prevent the depletion of self-control, according to research. Self-control can be difficult -- sticking with a diet or trying to focus attention on a boring textbook are hard things to do. Considerable research suggests one potential explanation for this difficulty: Exerting self-control for a long period seems to "deplete" our ability to exert self-control effectively on subsequent tasks.

New discovery helps solve mystery source of African lava

Posted: 23 Apr 2014 07:21 AM PDT

Floods of molten lava may sound like the stuff of apocalyptic theorists, but history is littered with evidence of such past events where vast lava outpourings originating deep in the Earth accompany the breakup of continents. New research shows that the source of some of these epic outpourings, however, may not be as deep as once thought. The results show that some of these lavas originated near the surface rather than deep within the mantle.

How Australia's Outback got one million feral camels: Camels culled on large scale

Posted: 23 Apr 2014 07:19 AM PDT

A new study has shed light on how an estimated one million-strong population of wild camels thriving in Australia's remote outback have become reviled as pests and culled on a large scale.

Political ravens? Ravens notice the relationships among others, study shows

Posted: 23 Apr 2014 07:19 AM PDT

Cognitive biologists have revealed that ravens do understand and keep track of the rank relations between other ravens. Such an ability has been known only from primates. Like many social mammals, ravens form different types of social relationships -- they may be friends, kin, or partners and they also form strict dominance relations. From a cognitive perspective, understanding one's own relationships to others is a key ability in daily social life ("knowing who is nice or not"). Yet, also understanding the relationships group members have with each other sets the stage for "political" maneuvers ("knowing who might support whom").

Picture books aren't just fun: Children learn sophisticated animal facts when parent read them

Posted: 23 Apr 2014 07:18 AM PDT

Children hear as much sophisticated information about animals when parents read picture book stories about animals as when they read flashcard-type animal vocabulary books, according to a new study. "Children do learn a lot when parents read books with them and many parents read to their children several times each week," said one researcher. "So, conducting studies using picture books and storybooks has important implications for understanding how children really learn in their daily lives."

2.5 million basketball injuries to high school athletes in 6 seasons, research finds

Posted: 23 Apr 2014 07:18 AM PDT

The first study to compare and describe the occurrence and distribution patterns of basketball-related injuries treated in emergency departments and the high school athletic training setting among adolescents and teens has been conducted. The study found that in general, injuries that are more easily diagnosed and treated, such as sprains/strains, were more likely to be treated onsite by an athletic trainer while more serious injuries, such as fractures, that require more extensive diagnostic and treatment procedures were more commonly treated in an ED.

Researchers compare hip width and sexual behavior

Posted: 23 Apr 2014 07:17 AM PDT

Hip width and risk of birth-related trauma may play a role in a woman's decision to have sex. Women who were more inclined to have one-night stands had wider hips, reveals a study into how a woman's build influences her sexual behavior. Results of the study show that the number of sexual partners a woman had is largely driven by one-night stand behavior. This, in turn, correlates with a woman's hip width and not waist-to-hip ratio. Overall, women in this study with hips wider than 14.2 inches had more sexual partners and more one-night stands than women with hips under 12.2 inches wide.

Inverse effects of midlife occupational, leisure time physical activity on mobility limitation in old age

Posted: 23 Apr 2014 07:17 AM PDT

Strenuous occupational physical activity in midlife increases the risk of mobility limitation in old age, whereas leisure-time physical activity decreases the risk. This is found in a study that followed up 5,200 public sector employees for 28 years. It states that heavy physical labor is often repetitive, wears the body and lasts for several hours a day. On the contrast, leisure-time physical activity is designed to improve fitness and provide recreation and a typical exercise session lasts for one or two hours. Even though both are based on muscle activity and result in energy expenditure, their long-term consequences are different.

Loss of memory in Alzheimer's mice models reversed through gene therapy

Posted: 23 Apr 2014 07:17 AM PDT

Alzheimer's disease is the most common cause of dementia and affects some 400,000 people in Spain alone. However, no effective cure has yet been found. One of the reasons for this is the lack of knowledge on the cellular mechanisms which cause alterations in nerve transmissions and the loss of memory in the initial stages of the disease. Researchers have now discovered the cellular mechanism involved in memory consolidation and were able to develop a gene therapy which reverses the loss of memory in mice models with initial stages of Alzheimer's disease.

Liquid spacetime: What if spacetime were a kind of fluid?

Posted: 23 Apr 2014 06:52 AM PDT

What if spacetime were a kind of fluid? This is the question tackled by theoretical physicists working on quantum gravity by creating models attempting to reconcile gravity and quantum mechanics. Some of these models predict that spacetime at the Planck scale is no longer continuous – as held by classical physics – but discrete in nature. Just like the solids or fluids we come into contact with every day, which can be seen as made up of atoms and molecules when observed at sufficient resolution. A structure of this kind generally implies, at very high energies, violations of Einstein's special relativity (a integral part of general relativity).

Cell division speed influences gene architecture

Posted: 23 Apr 2014 06:51 AM PDT

Speed-reading is a technique used to read quickly. It involves visual searching for clues to meaning and skipping non-essential words and/or sentences. Similarly in humans, biological systems are sometimes under selective pressure to quickly "read" genetic information. Genes that need to be read quickly are usually small, as the smaller the encoding message, the easier it will be to read them quickly. Now, researchers have discovered that, besides size, the gene architecture is also important to the optimization of the "reading" process.

Best practices in communication for animal world

Posted: 22 Apr 2014 05:23 PM PDT

Effective communication is not just about the signaler, according to a new study. The receiver also needs to assess the signaler efficiently. For instance, one of the most effective strategies from the perspective of female birds is assessing groups of males called leks, where females can assess multiple males in a short period of time.

Biting vs. chewing: Cutting their food helps kids behave better

Posted: 22 Apr 2014 05:23 PM PDT

There's a new secret to get your child to behave at the dinner table -- cut up their food! This new study found that when 6- to 10-year-old children ate food that they had to bite with their front teeth, chicken on the bone, they were rowdier than when the food had been cut into bite-sized pieces.

Getting at the root of mountain pine beetle's rapid habitat expansion

Posted: 22 Apr 2014 05:23 PM PDT

The mountain pine beetle has wreaked havoc in North America, across forests from the American Southwest to British Columbia and Alberta, with the potential to spread all the way to the Atlantic coast. Using a newly sequenced beetle genome, authors examined how the pine beetle could undergo such rapid habitat range expansion.

Brain circuits involved in emotion discovered by neuroscientists

Posted: 22 Apr 2014 05:23 PM PDT

A brain pathway that underlies the emotional behaviors critical for survival have been discovered by neuroscientists. The team has identified a chain of neural connections which links central survival circuits to the spinal cord, causing the body to freeze when experiencing fear. Understanding how these central neural pathways work is a fundamental step towards developing effective treatments for emotional disorders such as anxiety, panic attacks and phobias.

Insurance status affects where young adults seek health care

Posted: 22 Apr 2014 05:20 PM PDT

Perhaps due to lack of or inconsistent insurance coverage, young adults age 18 to 25 tend to go to the doctor's office less often than children or adolescents, yet have higher rates of emergency room use, finds a study. These findings are from a study of data from the 2009 Medical Expenditure Panel Survey, collected in advance of the implementation of the Affordable Care Act (ACA), which allows young adults to stay on family insurance plans until age 26 and makes it easier for them to obtain their own health insurance.

Cougars’ diverse diet helped them survive the mass extinction that wiped out the saber-tooth cat, American lion

Posted: 22 Apr 2014 05:20 PM PDT

Cougars may have survived the mass extinction that took place about 12,000 years ago because they were not particular about what they ate, unlike their more finicky cousins the saber-tooth cat and American lion who perished, according a new analysis of the microscopic wear marks on the teeth of fossil cougars, saber-tooth cats and American lions.

Physicists consider implications of recent revelations about the universe's first light

Posted: 22 Apr 2014 01:23 PM PDT

Recent evidence that the universe expanded from microscopic to cosmic size in a mere instant brings with it important implications. During a live Google Hangout, leading astrophysicists from the University of Chicago and Stanford University discussed what this potential 'crack in the cosmic egg' means for our understanding of the universe.

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