Benefit of excercise

Fox news reports that a new study shows that exercise is good for you.

Something to bear in mind. Remember correlation is not necessarily causation.

So the research shows that people who exercise vigorously had a reduced risk of dying regardless of bodyweight or chronic diseases.

75 minutes of vigorous exercise is all you need for the week

Some vigorous exercise gives some benefit on life span — reduced chance of early death.

Current recommendation is for 30 minutes of exercise per day.

If you can talk easily while exercising your are not doing it hard enough, Sweating is good. Heart should be really pumping, 7 or 8 out of 10 (maximum effort).

Any amount of exercise is better than none.

Unfortunately I don’t think Fox reported which study made these findings so I can’t see how accurately they reported on the findings of the paper.

Forbes (Alice G. Walton) report on this story (I presume) here: http://www.forbes.com/sites/alicegwalton/2015/04/06/vigorous-exercise-may-lengthen-lives-study-finds/

… a large new study in JAMA Internal Medicine suggests that indeed vigorous exercise, regardless of body weight or chronic disease status, can reduce early mortality significantly…

The researchers from James Cook University and the University of Sydney looked at data tracking over 204,000 participants, 45 and older, for an average of six and a half years. They were divided into three groups: those who engaged in only moderate activity, like leisurely swimming, social tennis, or even household chores; and people whose activity was vigorous (jogging, aerobics, or competitive tennis) up to 30% of the time, or more than 30% of the time.

This news story is based on the paper “Effect of Moderate to Vigorous Physical Activity on All-Cause Mortality in Middle-aged and Older Australians” by
Klaus Gebel, Ding Ding, Tien Chey, Emmanuel Stamatakis, Wendy J. Brown, Adrian E. Bauman. JAMA Intern Med. Published online April 06, 2015. doi:10.1001/jamainternmed.2015.0541

These are quotes from the abstract, the full abstract can be seen on-line for free if you search for the paper.

… Objective To examine whether the proportion of total moderate to vigorous activity (MVPA) that is achieved through vigorous activity is associated with all-cause mortality independently of the total amount of MVPA…

… Design, Setting, and Participants We performed a prospective cohort study with activity data linked to all-cause mortality data from February 1, 2006, through June 15, 2014, in 204 542 adults aged 45 through 75 years from the 45 and Up population-based cohort study from New South Wales, Australia (mean [SD] follow-up, 6.52 [1.23] years). Associations between different contributions of vigorous activity to total MVPA and mortality were examined using Cox proportional hazards models, adjusted for total MVPA and sociodemographic and health covariates…

Results During 1 444 927 person-years of follow-up, 7435 deaths were registered. Compared with those who reported no MVPA (crude death rate, 8.34%), the adjusted hazard ratios for all-cause mortality were 0.66 (95% CI, 0.61-0.71; crude death rate, 4.81%), 0.53 (95% CI, 0.48-0.57; crude death rate, 3.17%), and 0.46 (95% CI, 0.43-0.49; crude death rate, 2.64%) for reporting 10 through 149, 150 through 299, and 300 min/wk or more of activity, respectively. Among those who reported any MVPA, the proportion of vigorous activity revealed an inverse dose-response relationship with all-cause mortality: compared with those reporting no vigorous activity (crude death rate, 3.84%) the fully adjusted hazard ratio was 0.91 (95% CI, 0.84-0.98; crude death rate, 2.35%) in those who reported some vigorous activity (but <30% of total activity) and 0.87 (95% CI, 0.81-0.93; crude death rate, 2.08%) among those who reported 30% or more of activity as vigorous. These associations were consistent in men and women, across categories of body mass index and volume of MVPA, and in those with and without existing cardiovascular disease or diabetes mellitus.

…Conclusions and Relevance Among people reporting any activity, there was an inverse dose-response relationship between proportion of vigorous activity and mortality. Our findings suggest that vigorous activities should be endorsed in clinical and public health activity guidelines to maximize the population benefits of physical activity…

So not a bad job of reporting by Fox news.. they told us that a study exists although they added a lot of caveats to the results given that it is in line with current advice that exercise if good.

1 month’s free access to “Materials Science and Technology”

Maney publishing have made Materials Science and Technology to be their Journal of the month — if you sign up you can access the journal and back issues (from 1985 onwards) for the whole of November.

http://www.maneypublishing.com/index.php/journal-of-the-month-mst
We also have access to all the publications of the Royal Society for the whole of November Royal society celebrate open access week.

So the question is, which papers should we be reading from MST/ Phil Mag/ Proceedings of the Royal Society during November?

Royal Society Celebrate ‘Open Access week’

To celebrate open access, the royal society is giving free access to it’s 350-n years worth of publications (where n is the time in years till 30 November when it celebrates it’s 350th anniversary).

http://royalsocietypublishing.org/journals/

Incredibly low dislocation density in Steel

Gutierrez and Raabe have reported amazingly low dislocation density in Fe-3Si (wt.%) alloy after deforming to 500 MPa, using electron channeling contrast imaging in SEM-EBSD. In their paper “Dislocation density measurement by electron channeling contrast imaging in a scanning electron microscope“, published in Scripta Materialia, Vol 66, Issue 6, 2012. They report dislocation density of 10 ± 4 × 10-13 and 17 ± 6 × 10-13 m-2.

Boo typos 😦

Just for fun… lets imagine shortest dislocation to be 3 unit cells long and calculate the volume it would be found in (any shorter and we might be considered out dislocation to be some sort of point defect, but I wonder if there is criteria for shortest length?). 3 unit cells, so 2.8 * 3 = 9 nm. Volume = length/ density. 9 × 10-9 / 10 × 10-13 = 9000 m3. So one of our short dislocations would be found in a block 20 m × 20 m × 20 m.

A more usual dislocation density would be 10 × 1013. That means a length of 1014 m of dislocations in 1 cubed meter. That is equivalent to 100,000 km of dislocations in a 1 cm cube (a block of 1 cm × 1 cm × 1 cm). Or 100 km of dislocations in 1 mm cube. — A distance that would take more than 1 hour to ride on a motorbike, although it would be balance on the dislocations travelling at that speed.

The distance to the moon is 385,000 km, so we can only go 1/4 of the way there using the dislocation density I started with, also dislocations are space, and space is space too, so there are already dislocations there. It makes more sense to dig a tunnel with them…

Impression of what earth would look like if we introduced dislocations from surface (Burgers Vector not to scale).

The radius of Earth varies from 6,353 km to 6,384 km (Wikipedia), so there is a long enough length of dislocations in 1 cm cube of steel (if we take dislocation density to be 114 m/m3 still) to stretch to the centre of the earth 16 times, or to go all the way through the earth and come out the other side 8 times.

Newton Papers Online

http://cudl.lib.cam.ac.uk/collections/newton

New Podcasts

I made three new podcasts with Prof. Harry Bhadeshia on his latest papers on transformation texture, the new delta-Trip steels and on prediction of Hot Strength of ferritic steels.

The work on transformation texture is from Saurabh Kundu’s thesis were Patel and Cohen’s model has been shown to correctly predict the orientation relationship between ferrite and austenite after martensitic transformation. It’s shown that variants are selected by free energy differences that can be calculated depending on the orientation.

The delta-Trip steels were developed as a result of the prediction of neural networks, were after the neural network was made computer optimisation was used to try and maximise the mechanical properties. This work was done with Saurabh Chatterjee in collaboration with Murugananth Marimuthu. Both Saurabh Kundu and Saurabh Chatterjee completed their PhD’s at Cambridge while visiting from Tata Steel, Murugananth Marimuthu is a previous member of the phase transformations group, and has now also joined Tata Steel’s research and development section.

The work on Hot Strength of ferritic steels is the part of Radu Dmitriu’s topic of research. A neural network model of the hot-strength of ferritic steels. It was observed from the neural network that the strength is expected to suddenly start to decrease at 800 Kelvin, which can has been explained to be due to changes in the mobility of dislocations.

Addendum

According to wordpress documentation these links should get added to the rss feed of this bainite blog as enclosures.

Podcast: Hot Strength

Podcast: Delta Ferrite

Podcast: Transformation Texture

Subcribing to RSS Feed of this webpage should get you all the podcasts, or for Podcasts Only
Subscibe to RSS Feed for posts I remember to add to Podcasts category

Accessing Papers from University of Cambridge

The University of Cambridge news feed had notified about the new use of Raven Passwords to access electronic resources.

The ATHENS system of controlling access to networked services has been centrally funded as a national service for many years. That funding is being withdrawn by the JISC in favour of national Federated Access Control based on local user login.

ATHENS handles around 3 million users and 250 online services but it is a purely UK solution to providing access to remote services. The JISC have established that a
Federated solution using open source software and international standards will lead to a Single Sign On system with an individual using their institutional login to use both national and local services. This will also tie in with strategies for e-learning and e-science.

Raven is the web authentication system administered by University of Cambridge Computing Service.