This Way Up for Saturday 26 November 2016
Earthquake alerts, BBQ buyer's guide, are your gut microbes making you fat? and Canada's Great Trail.
Since the big Kaikoura earthquake last week there have already been well over 5,000 aftershocks, all logged and recorded by GeoNet – the earthquake and volcano monitoring system that sends alerts to smartphones and is made available on the web.
So how does the movement of the earth's crust get recorded and then broadcast as an alert to your phone within seconds? To discover how the information moves from a fault line in the South Island to your digital device we headed out with some of the team from GeoNet.
'The speed of the network even amazes me sometimes. I was sitting at home last night feeling the 5.7 near Culverden as my phone was alerting me of the same earthquake, so it was being picked up by our recorders in the South Island, transmitted to our servers in Avalon [in the North Island].... and was already being processed and initial estimates of the earthquake were being put out, as I was feeling the earthquake in Wellington' - Andrew Cowie, senior field technician, GeoNet
After the big quake, GeoNet was fielding up to 35,000 information requests per second, and got 233 million hits over the course of that first day. So how does the movement of the earth's crust get recorded, analysed, and then broadcast as an alert to your phone within a few seconds?
Well, as you might expect, technology plays a key role. A network of geophysical instruments transmit information about seismic movements using radio waves and cables to GNS Science's base in Lower Hutt where it is instantly analysed by an automated software application and then gets published automatically to the public. In fact, humans only really become involved in the process in the case of larger earthquakes (magnitude 4.5 and above) when a duty seismologist gets an alert, and has to examine the data.
To find out more about how the information moves from a fault line in the South Island to your digital device we headed out with Andrew Cowie a GNS Science senior field technician to Baring Head, a remote spot on the southern coast of the North Island. Baring Head is part of a network of more than 600 remote monitoring stations around New Zealand. It was here, at 12.02am on Monday 14 November, that data about the 7.8 magnitude earthquake started arriving from the Cape Campbell monitoring station located on the Marlborough coastline about 70 kilometres to the south.
"Top-scoring barbecues cooked everything evenly throughout, resulting in consistently tender and juicy meat. This also meant the barbecue's temperature was easy to control, and its heat was evenly distributed across the cooking surface" - George Block.
George Block of consumer.org.nz has been putting barbecues to the test, measuring how well they're made, how easy they are to use, and how well they cook steak, sausages, chicken wings, and the ultimate challenge... a whole chicken!
He tells This Way Up that with one manufacturer dominating the results, good budget options are hard to find.
"There's no reason an enterprising Kiwi manufacturer couldn't build on the simple lessons from the success of Weber grills, while adding some innovations of their own. Here's hoping next season we'll see some models that challenge Weber's supremacy, ideally at a price accessible to a wider range of Kiwis."
Eating high-calorie foods causes changes to the the bacteria living inside your gut which can hamper weight loss and contribute to yo-yo dieting, according to a new study.
The study suggests that the reason 80 percent of dieters relapse after losing weight, and even rebound to a higher body mass index within 12 months, could be down to their microbiomes - the unique communities of billions of bacteria which live on and inside us.
The researchers tried to replicate the effect of 'yo-yo dieting' in mice by alternating them between high-calorie and low-calorie diets. The composition of the mice's intestinal flora changed when you fed them calorific foods. And when the mice ate less food the metabolic consequences of being overweight, including raised cholesterol and insulin levels, were also reversed.
But the changes to the microbiome associated with an unhealthy diet persisted, almost lying dormant until the mice came off their diet and returned to eating less healthily. Christoph Thaiss and his colleagues found that it took over six months before these microbial populations started returning to their pre-obese state. And this time lag was important as exposure to an "obesogenic" environment before 6 months led to the weight returning quickly, and often rebounding to a higher level.
The study could have implications for the more than 40 percent of the world's population who are now overweight.
"The team speculate that this "lag effect" in the microbiome might be an evolved trait that, under normal circumstances, helps to maintain a stable state in the intestine. It prevents short-term changes in diet, or bouts of ill-health, from grossly changing our metabolic milieu. But in the world of plenty we now inhabit, it's turning out to be a pain in the posterior," Dr Smith said.
A 24,000km-long trail for trampers, cyclists and paddlers that links up the whole of Canada is nearly complete.
The Great Trail has been nearly 25 years in the planning but when all the work is done, hopefully next year to coincide with Canada's 150th anniversary, it will become the longest recreational trail in the world.
St John's in Newfoundland on the east coast will be linked by a network of paths and trails and waterways to Victoria near Vancouver on the west coast. And you'll even be able to take in Canada's rugged northern Arctic coastline on this trail, too!
Simon Morton talks with Valerie Pringle, co-chair of the Trans Canada Trail Foundation.