Did you know that sixty percent of your body weight is water? However, a loss of only two percent of this water through dehydration (脱水) during exercise can significantly affect your performance. The more you sweat, the more your exercise performance declines, unless you drink enough to replace your loss of fluids (液体).

    When you lose too much water, you can overheat quite easily, especially in a warm environment. But this is not the only problem you may face. Dehydration leads to your heart pumping much faster, which means exercise becomes more difficult and requires more effort. Despite these problems, however, many of us simply do not take enough fluids in when we head for the gym or set out on a run.

    So why is this? How do we manage to lose so much water without simply drinking more to replace it? Well, it's easier than you think. When we are at rest, we quickly become aware that we are thirsty and will put that right by having a drink. When we exercise, on the other hand, our thirst mechanism (结构) does not work as effectively, so we don't notice early enough that we are actually thirsty. In fact, we only start to fed thirsty when we have already lost around two percent of our body weight.

    Another problem is that, the more dehydration we become during exercise, the more difficult it is to prevent further dehydration-because our stomachs become intolerant (不能容忍的) to fluids and we do not absorb water properly, just when we need it most.

    The key thing about fluids and exercise is to manage your intake properly-regular small amounts are preferable, and some should be drunk before the period of exercise begins. You also need to match your intake to the sort of exercise you are doing. For example, for one hour of exercise, such as taking part in a 10 km run, you need to drink about two extra litres of water. For longer periods of exercise, sports drinks are recommended.

    I've recently published a book of letters from 32 amazing Australian women about their experiences of new motherhood. Perhaps the most common question I've been asked since publication is why more of the mothers didn't ask for help. If those early months were so hard and so exhausting as they were described, then why didn't more of these women simply ask for help?

Embedded (把……牢牢地嵌入) deep in this enquiry is the assumption that if you ask, you shall receive—and that you shall receive without judgment. And if there is any experience of new motherhood in the 21^st century it is the inescapability of judgment. By asking for help new mothers open themselves up to a wave of quiet—and not-so-quiet—disapproval of why on earth they need it.

    The earliest moments of motherhood are synonymous with sacrifice(等同于牺牲). A mother sacrifices her body for not nine but almost ten long months, sharing her shell with a new being. A mother sacrifices her control, and often her mental and physical health, during the painful process of childbirth. A mother, in the weeks and months that follow, puts the needs of another before her own, sacrificing her sense of self, her ambition and all too often, her happiness.

    We don't normally use the word sacrifice to describe the newborn period. It's supposed to be sweet and milky and warm but a sacrifice is exactly what it is. And when we sacrifice we should be entitled (使享有权利) to mourn—a privilege new mothers are expressly prevented from.

    We have reached the point where being a mother who admits she needs help is like saying your child isn't worth the sacrifice. The suffering has become a badge(徽章) of honor, worn in service to your family.

    The role of mothering is not an easy one, nor will it ever be. But it could be made more manageable if we were all to offer help or support.

A Chinese legend—A pretty maiden is trapped by a dragon. A prince must slay（杀死）the dragon to save her. Then, magically, they fall in love and live happily ever after. Traditional stories tend to emphasize the fantastic, magical side of love. Fate plays matchmaker. Strangers see each other from across a room and instantly know that they are destined to be together.

    It isn't difficult to imagine two strangers coming together and falling in love despite their differences. It suggests that love is challenging, uncertain, and incomprehensible.

    But with more people using online dating services, a very different kind of love has emerged: one that is scientific, convenient, and self-directed. It minimizes risk and provides a choice, like on a menu. There is anonymity（匿名）and the avoidance of immediate rejection. Meeting terms are negotiated online.

    Online dating also allows the setting of preconditions. Computer algorithms（推算） exclude undesirable traits such as the wrong hair color, race, or age. But they also exclude randomness. They reduce the chances of meeting someone different, or someone who could challenge one's romantic ideals. Instead, they find the partner we think we want and exclude everyone else. As a result, we could be missing the opportunity of a lifetime, to meet someone we would never have expected to fall in love with.

    Perhaps this new way represents a more efficient form of romance. Traditional ideas of love may be enchanting - but are they useful? Loneliness and boredom are less exciting than chance encounters, but they represent the more realistic side of love. All too often people have suffered through bad dates and humiliations. If they could just choose what they wanted, wouldn't it save time and reduce suffering? However, by choosing partners based on our preconceived ideas, we may be indulging in our illusions. Instead of letting ourselves grow with someone, love becomes more about looking for ourselves in the other. What if we don't know ourselves as well as we think? Perhaps love isn't about knowing what we want. Perhaps it's about being open to unimagined possibilities.

    Three years ago I worked for a few weeks as a doctor in a new dental clinic(牙科诊所）at Victor Harbor to the south of Adelaide and an hour further away than my usual workplace. My first day there was a driving to a new clinic and getting used to the clinical environment.

    As it was all new to me, I took off my rings: my wedding ring, and one that was an anniversary(周年纪念日)gift from my husband. I put them in a tissue(纸巾)and placed them beside my computer. During my lunch break, I noticed the tissue and thought that it did not look very clean and threw it into the rubbish bin. I went about my work and my day went well; I met new patients and felt that I had been productive

    Driving home at the end of the day, just moments before I reach that were missing. I felt the heat in my body rise, my cheeks(脸颊)burning red. I felt sick to my stomach.

    I spat an hour or so making calls, trying to find my rings. The first people I called were and clinical leader and they gave me a few phone numbers for cleaners I got in touch with already who managed the leaning services for the clinic, and she told me that the bins had already been collected.

    I knew nothing could be done now. I had lost my rings. Bu after two or so hours, I received the most amazing phone cal. The cleaner had gone through the bins and found my rings! I was so thankful to her, someone who had taken the trouble to go through the bins-which is not a pleasant task-to find my priceless rings.

    I worked at that clinic the following day, so I bought chocolates to thank this wonderful person. Unfortunately I did not get to meet her as she was not at work that day.

    Next month, I'm traveling to a remote area of Central Africa and my aim is to know enough Lingala — one of the local languages — to have a conversation. I wasn't sure how I was going to manage this — until I discovered a way to learn all the vocabulary I'm going to need. Thanks to Memrise, the application I'm using. It feels just like a game.

    "People often stop learning things because they feel they're not making progress or because it all feels like too much hard work," says Ed Cooke, one of the people who created Memrise. "We're trying to create a form of learning experience that is fun and is something you'd want to do instead of watching TV."

    Memrise gives you a few new words to learn and these are "seeds" which you plant in your "greenhouse". When you learn the words, you "water your plants". When the application believes that you've really memorized a word, it moves the word to your "garden". And if you forget to log on, the application sends you emails, reminding you to "water your plants".

    The application uses two principles about learning. The first is that people memorize things better when they link them to a picture in their mind. Memrise translates words into your own language, but it also encourages you to use "mems". For example, I memorized motele, the Lingala word for "engine", using a mem I created — I imagined an old engine in a motel (汽车旅馆) room.

    The second principle is that we need to stop after studying words and then repeat them again later, leaving time between study sessions. Memrise helps you with this, because it's the kind of application you only use for five or ten minutes a day.

    I've learnt hundreds of Lingala words with Memrise. I know this won't make me a fluent speaker, but I hope I'll be able to do more than just smile when I meet people in Congo. Now, I need to go and water my Vocabulary!

Humans' overconsumption of resources is a leading contributor to global climate change, says University of Arizona researcher Sabrina Helm. Therefore, it's increasingly important to understand the choices consumers make and how those decisions affect the health of a planet with limited resources. In a new study, published in the journal Young Consumers, Helm and her colleagues explore how materialistic values influence pro-environmental behaviors in millennials, who are now the nation's most influential group of consumers.

The researchers focused on two main categories of pro-environmental behaviors: reduced consumption, which includes actions like repairing instead of replacing older items; and "green buying," or purchasing products designed to limit environmental impacts. The researchers also looked at how engaging in pro-environmental behaviors affects consumer well-being.

More materialistic participants, the researchers found, were unlikely to engage in reduced consumption. However, materialism did not seem to have an effect on their likelihood of practicing "green buying." That's probably because "green buying," unlike reduced consumption, still offers a way for materialists to fulfill their desire to get new items, Helm said.

Study participants who reported having fewer materialistic values were much more likely to engage in reduced consumption. Consuming less was, in turn, linked to higher personal well-being and lower psychological suffering. Green buying—which may have some positive environmental effects, although to a smaller degree than reduced consumption—was not found to improve consumer well-being, Helm said.

The take-home message for consumers: "The key is to reduce consumption and not just buy green stuff. Having less and buying less can actually make us more satisfied and happier," Helm said. "If you have a lot of stuff, you have a lot on your mind," she said. "For example, it requires maintenance and there's a lot of burdens of ownership, and if you relieve yourself of that burden of ownership, most people report feeling a lot better and freer."

Helm and her colleagues additionally looked at how materialism affects millennial consumers' proactive financial behaviors, such as budgeting and saving. Examining financial behaviors alongside pro-environmental behaviors provides a picture of how young adults proactively deal with resource limitations in two contexts: environmental and financial, Helm said.

As expected, Helm and her colleagues found that those who reported having more materialistic values engaged in fewer proactive financial behaviors than their less materialistic counterparts (对应的人). The researchers also found that, consistent with previous studies, proactive financial behaviors were associated with better personal well-being, life satisfaction and financial satisfaction, as well as lower psychological suffering.

Understanding how materialistic values impact consumer behaviors, and how those behaviors in turn affect personal and environmental well-being, is important, Helm said. However, she acknowledges that for many consumers, shifting behaviors to be more financially proactive and consume less will be challenging.