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    Anyone who has ever tried to stop smoking knows how difficult it is to quit. There is no lack of information about how unhealthy smoking is for you- not to mention the unpleasant smell. So why would teens ever begin to smoke?

    {#blank#}1{#/blank#} Research shows that the majority of smokers lit up their first cigarette in their early or mid-teens, precisely at a time when children are beginning to establish their own identity apart from their parents. Smoking can be an act of rebellion(反抗) against parents or authority figures, as well as a way to fit in with others and feel accepted.

    Here are some things that parents can do to help a child stay smoke-free.

    Start talking to your teen about how bad smoking is for him early, well before his teens. Keep talking, too. {#blank#}2{#/blank#}

    {#blank#}3{#/blank#} For example, smoking makes your hair and clothing smell bad, stains the teeth, and reduces your lung power to play sports.

    {#blank#}4{#/blank#} Talk about the addictive power of smoking and tell him while those few cigarettes are his choice, the addiction that occurs shortly afterwards makes him powerless to decide whether or not he wants to light up.

    Work on self-esteem(自尊) and self-confident with your teen. Much of the attraction of smoking is to gain acceptance. {#blank#}5{#/blank#}

    Residents in the poorest counties in the U.S. face a life expectancy up to decade shorter than their counterparts in the wealthiest areas, according to a study published in the American Journal of Public Health.

    Researchers from East Tennessee State University wanted to better understand how socioeconomic status was associated with heath outcomes. To find out they divided the country's 3,141 counties into 50 new 'states' (with 2 percent of the counties in each) based on household income as opposed to geographic proximity (接近).

    The researchers broke down the data by county since they found state-level data may hide some 'impact of socioeconomic differences on both the best-off and worst-off counties.' They then examined health data from the wealthiest and poorest 'states' (top and bottom 2 percent) to see how residents differed on factors like smoking, clinical care and excessive drinking. Researchers found that there was nearly a 10-year gap in the life expectancy of men with an average of 79.3 years in the wealthy counties compared to 69.8 years in the poorest. For women, the difference was slightly less - 83 years in the wealthiest counties and 76 years in the poorest.

    The study authors caution that while they found a connection between socioeconomic status and health outcomes, they did not analyze cause and effect. But they suggest that the data shows how policy makers should not just focus on state-wide initiatives (主动性) but more targeted efforts to help those most at risk. “With limited resources, methods of pinpointing the poorest counties can assist in the allocation of resources and programs to those communities that are in the greatest need,'' the study authors wrote.

    There are an unbelievable number of reasons to go to Greece; just like there are an unbelievable number of things to do once a traveler arrives there. Here is a look at just some of the great historical things to see when on holiday in Athens, Greece.

    Agora

    Agora lies in ruins now, but during its glory days it was a lively and active open marketplace where Greeks came to buy, sell, and exchange their goods and services. Agora has ties to common people of ancient Greece.  Guided tours are available and there is also a small museum with many artifacts from this area on display.

    Parthenon

    One of the most famous landmarks in Athens is the legendary Parthenon. This building is still today admired by architects who are appreciative of the decorative design, as well as the engineering involved in its construction.  Those interested in history will be impressed beyond belief with the opportunity to see this historic structure up close and personal.

    Temple of Olympian Zeus

    One of the most impressive monuments to see up close is the Temple of Olympian Zeus. Many people see this monument from far away, or even from the window of a taxi, and never stop for a first hand look themselves. This is a huge mistake as the size of it cannot truly be appreciated without visiting it up close.

    Odeum of Herodes Atticus

    Built into the hillside and providing a nice view of Athens is the Odeum of Herodes Atticus. This theater was constructed in the second century and was an important gathering place for both the upper and lower classes. It holds a little over 5,000 people, is located just below the Acropolis, and is still used for performances to this day.

    People typically wash their hands seven times a day in the United States, but they do it at a far higher temperature than is necessary to kill germs, a new study says. The energy waste is equivalent to the fuel use of a small country. Amanda R. Carrico, a research assistant professor at the Vanderbilt Institute for Energy and Environment in Tennessee, told National Geographic that hand washing is often “a case where people act in ways that they think are in their best interest, but they in fact have inaccurate beliefs or outdated perceptions.”

    Carrico said, “It's certainly true that heat kills bacteria, but if you were going to use hot water to kill them it would have to be a way too hot for you to tolerate.”

Carrico said that after a review of the scientific literature, her team found “no evidence that using hot water that a person could stand would have any benefit in killing bacteria.” Even water as cold as 40°F (4.4℃) appeared to reduce bacteria as well as hotter water, if hands were scrubbed, rinsed(冲洗)and dried properly.

    Using hot water to wash hands is therefore unnecessary, as well as wasteful, Carrico said, particularly when it comes to the environment. According to her research, people use warm or hot water 64 percent of the time when they wash their hands. Using that number, Carrico's team calculated a significant impact on the planet.

    “Although the choice of water temperature during a single hand wash may appear unimportant, when multiplied by the nearly 800 billion hand washes performed by Americans each year, this practice results in more than 6 million metric tons of CO2 equivalent emissions annually,” she said.

    The researchers published their results in the July 2013 issue of International Journal of Consumer Studies. They recommended washing with water that is at a “comfortable” temperature, which they noted may be warmer in cold months and cooler in hot ones.

    This year's flu season is pretty scary. To try to minimize the effects, public officials are still urging anyone who hasn't yet gotten their flu shot to get one as soon as possible. However, even if every single person got a shot in the arm, the vaccine(疫苗)—with its excellent 36 percent effectiveness—would not prevent everyone from getting infected with the annoying virus. Knowledge is power, so here's what goes on in your body when you come down with the flu.

    The influenza virus primarily attacks your nose, throat, and the tubes that lead to your lungs. But the flu is so much more than that. Your muscles ache, your head hurts, and your appetite goes down, among other things. To our surprise, almost all of these symptoms have less to do with the virus itself than with your immune(免疫的)response to them. Unfortunately, the very defense you have in place to get rid of the flu is the reason you feel so painful when you recover.

    The virus usually enters through your mouth, typically by way of your hands But it takes a few days for symptoms to set in. While this process might cause some harm to your nose and throat, it's nothing major, and nothing like the symptoms that typically accompany a bad or even mild case of the flu.

    The real fun starts when your immune system begins to fight. Your immune system comes in two parts: the innate system and the adaptive. The innate immune system is essentially an all-purpose tool. As soon as your body senses the presence of any injury or invader (入侵者), the innate immune system launches into action by producing tiny proteins called cytokines and chemokines. The cytokines reproduce almost immediately and start to attack the virus. This increase in immune cells creates an serious inflammation(炎症) throughout the body. But the worst is still to come. Meanwhile, the chemokines work with the adaptive immune system to help create T cells. These cells are a special type of white blood cell that works in a much more specific way: They find the influenza virus, identify what's special about it, and create something unique on their surface that finds and destroys similar invaders.

    Shark attacks not only disturb beach activities, but can affect associated tourist industries. Shark nets are a common solution to preventing shark attacks on beaches, but they cause dangers to sea ecosystems.

    Seeking a cost-effective way to monitor beach safety over large areas, we have developed a system called Shark Spotter. It combines artificial intelligence (AI), computing power, and drone (无人机) technology to identify and warn lifesavers to sharks near swimmers. The project is a cooperation between the University of Technology Sydney and The Ripper Group, which is pioneering the use of drones—called "Westpac Little Ripper Lifesavers"—in the search and rescue movement in Australia.

    SharkSpotter can detect sharks and other potential threats using real-time aerial imagery. The system analyses video from a camera attached to a drone to monitor beaches for sharks, send warnings, and conduct rescues. Developed with techniques known as "deep learning", the Shark Spotter system receives imagery from the drone camera and attempts to identify all objects in the scene. Once certain objects are detected, they are put into one of 16 categories: shark, whale, dolphin, rays, different types of boats, surfers, and swimmers.

    If a shark is detected, Shark Spotter provides both a visual sign on the computer screen and an audible warning to the operator. The operator confirms the warning and sends text messages from the Shark Spotter system to the Surf Life Savers for further action. In an emergency, the drone is equipped with a lifesaving flotation pod (漂浮仓) together with an electronic shark repellent (驱逐装置) that can be dropped into the water in cases where swimmers are in severe trouble, trapped in a rip, or if there are sharks close by.

    In January 2018, the Westpac Little Ripper Lifesavers was used to rescue two young swimmers caught in a rip at Lennox Head, NSW. The drone flew down the beach some 800 meters from the lifeguard station, and a lifesaving flotation pod was dropped from the drone. The complete rescue operation took 70 seconds.

    We believe Shark Spotter is a win-win for both marine life and beachgoers. This unique technology combines dynamic video image processing AI and advanced drone technology to creatively deal with the global challenge of ensuring safe beaches, protecting environments, and promoting tourism.