Why GTA genes can’t be maintained by ‘selfish’ transmission

Below is the line of reasoning showing that the genes responsible for producing GTA particles cannot maintain themselves or spread into new populations by GTA-mediated transfer of themselves into new cells.  I initially worked this out with a rigorous set of mathematical equations, but then realized that the problem was so glaringly obvious that math isn't needed.The main GTA gene cluster is too big to fit inside a single GTA particle, so GTA particles can't…

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Might GTA be a vaccination system for infecting phages?

My work at Dartmouth (to be described in upcoming posts) showed conclusively that genes encoding Gene Transfer Agents (such as the GTA system of Rhodobacter capsulatus) cannot be maintained by 'selfish' transfer of either whole GTA gene clusters or single GTA genes into GA- recipients.  Neither can the GTA genes be maintained by general recombination benefits that can arise when fragments of chromosomal DNA are transferred into new cells.  So, although 'gene transfer agent' does…

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What are you doing on that screen of yours?

A few years ago we were with my wife’s family for the holidays.  I often read a lot over the holidays, and at the time I was doing most of my reading on my iPad.  This was before my son was born, so I could easily read for 1-2 hours/day during the holidays.  So I was on my iPad an awful lot. At one point my mother-in-law asked what I was working on.  At the…

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Let Them Sniff and Early Socialization

Two recent posts considered how to make the world better for dogs and how to make the world better for cats. An incredible set of experts gave their answers to the questions, with wonderful ideas for a better world for our animals.I am making images for each answer to share on social media.These are the first two. I am working my way through in somewhat random order (not truly random because if I happen to…

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Nominations now open for the 2018 Canadian Blood Services Lifetime Achievement Award

Do you know someone who has made an outstanding contribution to the blood system in Canada?   Who can be nominated?  Recipients of the Canadian Blood Services Lifetime Achievement Award are individuals whose landmark contributions are recognized as both extraordinary and world class in the field of transfusion or transplantation medicine, stem cell or cord blood research in Canada and/or abroad.

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The Baseball Batter’s Predictive Brain

For some years now, cognitive scientists have increasingly come to regard the human brain as a machine for making predictions. In other words, these scientists think that our brains spend most of their time trying to figure out what is going to happen next so that they can take action accordingly. The great adaptive value of such a process is immediately obvious. The theoretical framework underlying this view of things is extensive and fairly new,…

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Des capacités d’intégration neuronale bien plus complexes qu’on le croyait depuis des décennies ?

Pourquoi ne pas commencer l’année avec un billet sur une découverte qui a des allures de révolution ? C’est du moins ce que laisse sous-entendre des titres comme : « Physicists Negate Century-Old Assumption Regarding Neurons and Brain Activity » ! Qu’en est-il au juste ? Et d’abord quel phénomène neuronal serait ici remis en question ? Rien de moins que le processus de base de ce qu’on appelle l’intégration neuronale : le fait que…

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What you get for what you gave: Why yield is an important metric in the development of CGTs.

  In this month’s blog on addressing specific bioprocess and bioanalytical challenges to develop Cell and Gene Therapies (CGTs), we hear from Dr. Nick Timmins on quantifying performance of CGTs using cell yield, and some of the methods to measure it, as a metric of optimized manufacturing of CGTs. (SV) Nick Timmins is VP, Process Science at BlueRock Therapeutics – a company focused on harnessing the power of induced pluripotent stem cells as a manufacturing…

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036 – Diets and Californian Cell Phones

  Dr. Yoni Freedhoff guest stars to discuss our changing food environment. He talks dieting, The Biggest Loser, food frequency questionnaires, and the Cornell Food Lab fiasco. He also valiantly defends his children against the Don Drapers of the world. Also on the show: California issues guidelines for people worried about cell phones and how these guidelines were released is a really wacky story involving "FREEEEDOM!"; electricity to fight cancer; and Chris' The More You…

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What tool should we use to measure sedentary behaviour in population health surveys?

Article: Prince SA, LeBlanc AG, Colley RC, Saunders TJ. Measurement of sedentary behaviour in population health surveys: a review and recommendations. PeerJ 2017;5:e4130. Travis’ Note: Today’s post comes from friend and colleague Dr Stephanie Prince, and details a recent collaboration in which we (along with Drs Allana LeBlanc and Rachel Colley) reviewed the current questionnaires available for measuring sedentary behaviour, and offer evidence-based suggestions for moving forward.  The result is the International Sedentary Assessment Tool,…

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