What is a sonar pulse and how can it injure humans under water?

Christine Erbe, Curtin UniversityOver the weekend, the Australian government revealed that last Tuesday its navy divers had sustained “minor injuries”, likely due to sonar pulses from a Chinese navy vessel. The divers had been clearing fishing nets from the propellers of HMAS Toowoomba while in international waters off the coast of Japan. According to a statement from deputy prime minister Richard Marles, despite HMAS Toowoomba communicating with internationally recognised signals, the Chinese vessel approached the Australian ship and turned on its sonar, forcing the Australian divers to exit the water. The incident prompted a response from the Australian government, who labelled the incident “unsafe and unprofessional”. But what exactly is a sonar pulse, and what kinds of injuries can sonar cause to divers? What is sonar? Light doesn’t travel well under water – even in clear waters, you can see perhaps some tens of metres. Sound, however, travels very well and far under water. This is because water is much denser than air, and so can respond faster and better to acoustic pressure waves – sound waves. Because of these properties, ships use sonar to navigate through the ocean and to “see” under water. The word “sonar” stands for sound navigation and ranging. Sonar equipment sends out short acoustic (sound) pulses or pings,...

Read More........→November 22, 2023

Fieldwork can be challenging for female scientists. Here are 5 ways to make it better

Sarah Hamylton, University of Wollongong; Ana Vila Concejo, University of Sydney; Hannah Power, University of Newcastle, and Shari L Gallop, University of WaikatoWomen coastal scientists face multiple barriers to getting into the field for research. These include negative perceptions of their physical capabilities, not being included in trips, caring responsibilities at home and a lack of field facilities for women. Even if women clear these barriers, the experience can be challenging. This is a problem because fieldwork is crucial for gathering data, inspiring emerging scientists, developing skills, expanding networks and participating in collaborative research. Our recent study revisited an international survey of 314 coastal scientists that revealed broad perceptions and experiences of gender inequality in coastal sciences. We offer five ways to improve the fieldwork experience for women. Our collective experience of more than 70 years as active coastal scientists suggests women face ongoing problems when they go to the field. Against a global backdrop of the #MeToo movement, the Picture a Scientist documentary and media coverage about incidents of sexual harassment in the field, conversations between fieldworkers and research managers about behaviour and policy change are needed. Our research: what we did and what we...

Read More........→November 06, 2023

Is it okay to kiss your pet? The risk of animal-borne diseases is small, but real

Shutterstock Sarah McLean, Swinburne University of Technology and Enzo Palombo, Swinburne University of Technology Our relationship with pets has changed drastically in recent decades. Pet ownership is at an all-time high, with a recent survey finding 69% of Australian households have at least one pet. We spend an estimated A$33 billion every year on caring for our fur babies. While owning a pet is linked to numerous mental and physical health benefits, our pets can also harbour infectious diseases that can sometimes be passed on to us. For most people, the risk is low. But some, such as pregnant people and those with weakened immune systems, are at greater risk of getting sick from animals. So, it’s important to know the risks and take necessary precautions to prevent infections.  What diseases can pets carry? Infectious diseases that move from animals to humans are called zoonotic diseases or zoonoses. More than 70 pathogens of companion animals are known to be transmissible to people. Sometimes, a pet that has a zoonotic pathogen may look sick. But often there may be no visible symptoms, making it easier for you to catch it, because you don’t suspect your pet of harbouring germs. Zoonoses can be transmitted directly from pets to humans, such as through contact with saliva, bodily fluids and faeces, or indirectly, such as...

Read More........→September 06, 2023

Why Should You Breastfeed Your Baby?

(Photo courtesy of Flushing Hospital Medical Center)Flushing Hospital Medical Center’s New Beginnings unit provides the women and their families with the ultimate birthing experience. Each month, we cover a new topic exploring an important aspect of health and well-being for expectant mothers. This month, we’ll cover the health benefits of exclusive breastfeeding for both mothers and their babies. According to the American Academy of Pediatrics, exclusive breastfeeding involves only feeding breast milk to your baby and no other foods or liquids. It is the best source of nutrition for your infant’s first six months of life. Some of the benefits to babies and mothers include: Providing all necessary nutrients for the baby’s healthy physical development, including vitamin D, iron, and zincPreventing infections and serious health conditions, both during infancy and later in lifeReducing a mother’s risk of conditions such as cancer, type 2 diabetes, and high blood pressureBreastfeeding may become less frequent as your baby starts eating solid foods around six to 12 months of age. For guidance on how you should breastfeed your baby, talk to a lactation consultant or your baby’s doctor or nurse.Flushing Hospital’s New Beginnings unit offers spacious, modern delivery suites and advanced postpartum care, providing you with a safe...

Read More........→August 23, 2023

What’s the difference between skim milk and light milk?

Margaret Murray, Swinburne University of TechnologyIf you’re browsing the supermarket fridge for reduced-fat milk, it’s easy to be confused by the many different types. You can find options labelled skim, skimmed, skinny, no fat, extra light, lite, light, low fat, reduced fat, semi skim and HiLo (high calcium, low fat). So what’s the difference between two of these common milks – skim milk and light milk? How are they made? And which one’s healthier? What do they contain? Skim milk In Australia and New Zealand, skim milk is defined as milk that contains no more than 1.5% milk fat and has at least 3% protein. On the nutrition information panel this looks like less than 1.5 grams of fat and at least 3g protein per 100 millilitres of milk. But the fat content of skim milk can be as low as 0.1% or 0.1g per 100mL. Light milk Light milk is sometimes spelled “lite” but they’re essentially the same thing. While light milk is not specifically defined in Australia and New Zealand, the term “light” is defined for food generally. If we apply the rules to milk, we can say light milk must contain no more than 2.4% fat (2.4g fat per 100mL). In other words, light milk contains more fat than skim milk. You can find the fat content by reading the “total fat per 100mL” on the label’s nutrition information panel. How about other nutrients? The...

Read More........→June 14, 2023