In a simulation using atomic force microscopy, four water molecules bond with a sodium ion one by one (A to D). A fifth water molecule (white spot at lower left) bonds with the hydrated sodium ion. As one sodium ion can only bond with four water molecules tightly at most, the fifth one can only bond outside. (E) An artist's rendering of a hydrated sodium ion with three water molecules. (F) Chinese scientists have become the first to directly observe the atomic structure of a hydrated sodium ion-the basic chemical makeup of seawater. The technology can be used to study other water-based liquids, opening new avenues for molecular and materials sciences, experts said on Monday in the science journal Nature. It is the first time scientists have been able to visualize the atomic structure of hydrated ions in their natural environment since the notion was proposed more than a hundred years ago. The same team of scientists also discovered that exactly three water molecules are needed to allow a single sodium ion to travel 10 to 100 times faster than other ion hydrates-a process that could lead to more efficient ion batteries, anti-corrosion coatings and seawater desalination plants, according to the Nature article. Water is the most plentiful liquid on Earth. Its simple chemical structure-two hydrogen atoms bonded to one oxygen atom-is the basic building block of most life on Earth, said Wang Enge, a physicist and academician of the Chinese Academy of Sciences. But the science behind water, especially regarding its structure and interaction with other chemicals, is extremely hard and not well understood, Wang said. In 2005, the journal Science listed the structure of water as one of the most compelling scientific puzzles, despite a century's worth of research having been done. Since the late 19th century, scientists have been studying ion hydration, a process in which water dissolves soluble materials such as sodium chloride, or salt. Although the process is extremely common in nature, exactly how it works at an atomic level has remained a mystery. The main reason for water's complexity is its simplicity, said Jiang Ying, a professor at Peking University's International Center for Quantum Materials, who was part of the study. Because hydrogen atoms are so simple and small compared with the oxygen atom, the weird properties of quantum mechanics start to interfere with experiments and make them less predictable, he said. Therefore, it is crucial for scientists to directly see how water interacts with other materials at an atomic level. By using new atomic force microscopy developed by Chinese scientists, it's possible to see even the smallest changes in a single water molecule's structure around the ions, Jiang said. Scientists found that three water molecules surrounding a single sodium ion can travel exceptionally fast on a sodium chloride molecule's surface. This sublime phenomenon can occur at room temperature, but also applies with other chemical ions such as potassium ions-one of the key ions necessary for neural cell communication. Although the magic number for each type of ion might be different, the phenomenon is a game changer for ion-related fields, he said. For example, engineers can alter the flow speed of lithium ions in batteries to make them charge faster or store more power. Scientists can also create special filter systems that can change the number of water molecules surrounding an ion, thus speeding up or reducing the filtering speed according to specific needs. This discovery also allows scientists to have a better understanding of how cells communicate with each other by exchanging ions through channels on their membranes, Jiang said. This has potentially profound scientific implications for future applications in biology and medicine, he said, adding that two Nobel Prizes were given to research related to ion channels in the last two decades-one for their discovery in 1991 and the other for their mechanisms in channeling water in 2003. custom bar bracelet
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With an increasing number of males seeking cosmetic surgery on their genitals, more efforts are needed to regulate the services to ensure safety, said the head of a special committee of the Chinese Medical Doctor Association.Patients range from teenagers to seniors, but most of them are young, said Tian Long, director of the association's male reproductive organ plastic surgery and recovery committee and a doctor of andrology, or male medicine, at Beijing Chaoyang Hospital.Some of them seek surgery because they feel there's a problem with their genitals, such as being too small or deformed, which causes psychological problems and makes them shy in social interactions, such as worrying about using public restrooms or not daring to seek a girlfriend, Tian said.Some, though, have no abnormalities but have unrealistic expectations of size - either their own or their spouses', he said."These conditions can create heavy psychological pressure, and some people are even prone to violence," he said. "Some problems result in divorces."Although cosmetic surgery on the male genitals has been performed in China for many years, techniques vary greatly between hospitals and regions, and there is a lack of unified standards, Tian said.Promotional advertisements for surgeries that don't really work are rampant on the internet, he said."Such surgery, if improperly done, can result in serious negative impacts on patients, such as genital infection, pain and erection problems due to damage to blood vessels or nerves," he said."Such surgeries have been a major cause of medical disputes between hospitals and patients, especially for private hospitals that lack qualified talent."To meet increasing demand and regulate the services, the male reproductive organ committee was set up in mid-December in Wuhan, Hubei province."By setting up the committee we hope diagnoses and surgeries can be regulated, standards can be established and promoted and technological breakthroughs can be made in such surgeries to improve their efficacy and safety," he said.The committee comprises about 50 andrology experts from major hospitals in China, most of them from big hospitals in cities such as Beijing, Shanghai and Wuhan, he said."The number of surgeries conducted to extend or thicken the penis is estimated at more than 10,000 a year nationwide," he said. "More surgeries are conducted on patients with diseases in their reproductive system, such as infection caused by injuries, urinary tract diseases and cancer of the penis."Demand for cosmetic surgery on male genitals has also been increasing in recent years, driven by higher sexual expectations for the patient or his partner and the pursuit of psychological comfort, he said.In the andrology department of Beijing Chaoyang Hospital, doctors perform between 1,000 and 2,000 surgeries on penises every year, about half of them cosmetic surgeries, which is at least twice as much as 10 years ago, according to Tian."In recent years we have seen an increasing number of males coming for advise or treatment for their reproductive organs," he said. "Young men are having higher expectations of sex, and many of them want their penis to be bigger, or have a particular shape. Some also wish to make their penis look good, and ask for cosmetic surgery."Zhang Zhichao, a professor at Peking University First Hospital's Andrology Department, said that while demand for genital surgery is high among males, irregularities in the industry such as misdiagnosis and treatment driven by profit are rampant due to lack of supervision."Cosmetic surgeries have been excessively and improperly conducted in many hospitals," he said. "In some cases patients who have sexual malfunctions and should have operations for treatment ended up receiving cosmetic surgery that will not help them improve their sexual ability."In some cases patients' poor sexual performance is psychological rather than physiological, and they should not rely on surgery to improve their performance, he said.More effective supervision from health authorities is needed to check such irregularities and protect the interests of patients, he said.
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