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Dr. John Jurist, Sunday, 2-16-14 February 17, 2014

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Dr. John Jurist, Sunday, 2-16-14

Artificial Gravity

http://archived.thespaceshow.com/shows/2188-BWB-2014-02-16.mp3

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Guest:  Dr. John Jurist.  Topics: Artificial gravity, spinning, tethers, rotation rates, the gravity gradient & more.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://thespaceshow.wordpress.com.  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See www.onegiantleapfoundation.org/amazon.htm.

We welcomed back Dr. John Jurist for this two hour discussion on all aspects of artificial gravity.  Note that Dr. Jurist prepared presentation material for this program which you will find on the archived blog entry for this discussion.  Also, I recommend you read the excellent article by our UK guest, inventor, & friend, Robert Walker, “Can Spinning Habs Solve the Zero g Health Issues?  Can Humans Live in Mars or Lunar g? Why Nobody Knows.” (see www.science20.com/print/129424).  During our first segment, Dr. Jurist introduced us to the basics of artificial gravity including the Coriolis effect, the gravity gradient & the info needed from in-space artificial gravity R&D.  Several studies including one by UC Irvine were mentioned, plus other bed rest studies.  He also talked about the Wyle Centrifuge studies which used a short arm for experimentation.  Our attention turned to the presentation material on TSS blog titled “Artificial Gravity Comments–JmJurist.”  Dr. Jurist took us through the tables & charts on his two page document.  He was asked about gender & age differences with gravity as well as small rodent/mammal ISS experiments now or in the future.  Our first caller was John from Ft. Worth who clarified some of his comments from the last Open Lines show plus he talked about the hardware, infrastructure, & engineering issues for in-space experiments.  We talked about the use of tethers & the relationship with microgravity & radiation issues.  With our caller still with us, Jenna emailed asking if either Mars One or Inspiration Mars would provide the needed research that never seems to be done by NASA or others.

In the second segment, Doug from S. California called.  He talked about his T frame tetherball type structure concept as an interim artificial gravity tool but said it was not a long term solution.  He also inquired about tethers, then he wanted to know about the mass of possible tether cables as well as potential materials that could be used for in-space tethers.  Doug then described a reference mission using a long arm centrifuge for the surface of the Moon.  Doug described a very good concept and Dr. Jurist had much to say about it.  We had quite the discussion on possible implementation strategies and the roadmap from theory to operations given our current policy & economic environment, plus the track record on other large projects that never made it.  With Doug on the phone, Ft. Worth John emailed to inquire about stability issues and tidal forces on the tether.  Both Dr. Jurist & Doug made a pass at providing John an answer to his question.  In his closing statement, our guest went over some basic advantages with a tether, the problems of the gravity gradient & the fact that the issues for colonization were very different than for experiments or a reference mission.

Please post your comments/questions on TSS blog above.  If you want to reach Dr. Jurist or our callers, do so through me.

Dr. Mindy Howard, Monday, 6-10-13 June 11, 2013

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Dr. Mindy Howard, Monday, 6-10-13

http://archived.thespaceshow.com/shows/2026-BWB-2013-06-10.mp3

Guest:  Dr. Mindy Howard.  Topics:  Addressing the mental and emotional challenges that may be experienced during commercial space flight.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://thespaceshow.wordpress.com.  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information.

We welcomed Dr. Mindy Howard to the program for our 1 hour 30 minute discussion about the psychological issues and training for commercial astronauts.  During our first segment, Dr. Howard introduced us to many of the issues that will be faced by commercial astronauts, including psychological aspects.  Our guest described her business, Inner Space Training (see http://innerspacetraining.com) and the benefits that her training offers commercial astronauts, especially if the training is engaged a few months in advance of the actual spaceflight.  Dr. Howard was asked if in her research she noticed differences among potential commercial astronauts based on age, gender, physical fitness, or other metrics.  In addition, our guest explained brain wave theory and the use of the MindSpa device for the training.  Dr. Howard was asked about training in Holland and Europe as well as here in the States, plus individual and/or group training.  As for her Inner Space Training program, it lasts one day but “homework” follows for several weeks to a month or two in advance of the actual flight, especially using the MindSpa tool which you use and learn in the formal part of the one day training program.

In our second segment, we talked about commercial astronaut peaks, performance, and flow.  We also addressed more issues regarding training for a long duration flight such as Inspiration Mars.  Dr. Howard did go into some detail about peak experiences, especially when I suggested that the entire flight to Mars might be a peak experience.  However, when properly defined, the entire Martian trip would not be a peak experience though it would likely be very exciting. I also asked her how she might modify her training to include the longer Mars flight.  Toward the end of the program, we talked about the business need for the space tourism programs to make this type of training mandatory to help assure all participants/customers have a successful flight experience.  Dr. Howard provided a few examples in support of my suggestion that this type of training be required & included by the space companies.

Please post your comments/questions on The Space Show blog.  You can also email Dr. Howard at mindyhoward@innerspacetraining.com.

Dr. John Jurist, Tuesday, 3-27-12 March 27, 2012

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Dr. John Jurist, Tuesday, 3-27-12

http://archived.thespaceshow.com/shows/1744-BWB-2012-03-27.mp3

Part 1, Bisphosphonate Usage in Microgravity

Guest:  Dr. John Jurist.  Topics:  This is the first in a series of programs focused on the use of bisphosphonates to mitigate bone loss in long duration spaceflight.  You are invited to comment, ask questions, & discuss the Space Show program/guest(s) on the Space Show blog, https://thespaceshow.wordpress.com. Comments, questions, & any discussion must be relevant & applicable to Space Show programming. Transcripts of Space Show programs are not permitted without prior written consent from The Space Show (even if for personal use) & are a violation of the Space Show copyright.  We welcomed back Dr. John Jurist for the first of several programs devoted to understanding bone loss in microgravity & the use of prescription the bisphosphonate family of drugs to mitigate the problem.  Dr. Jurist provided talking points which you can find below this summary on The Space Show blog.  A significant portion of the second segment is devoted to understanding these talking points so follow along.  We started our discussion with an explanation of the bone loss problem facing those in microgravity.  Following this brief overview, Dr. Jurist told us about bisphosphonates, the origins of this drug, how it was developed, how its usage, what some of the side effects are, some of the trials that have been associated with the drug, & space/NASA studies.  Later in this nearly hour long segment, we talked about the human population & what happens to our bone mass at various stages in our life. We talked about gender, racial, & ethnic differences in human bone mass issues.  As you will hear, there are gender & other differences among our diverse population.  This led us to asking about using targeted genetics in selecting crews for longer spaceflight missions.  Genetic modification was mentioned, especially for the long term, but for the near term, looking for better exercise routines & pharmaceutical modification/treatment seem to hold the most promise.  Dr. Jurist then talked about bisphosphonate side effects.  Fast transit time to Mars or a long duration mission destination came up. As you will hear, even if you get to Mars faster, you still have the problem on the surface of Mars.  The big problem is we have no credible information on what the gravity prescription for humans needs to be so we do not know if Martian gravity is sufficient to mitigate the problem.  Next, we focused on the need for an orbiting centrifuge, we talked about the size & spin rate of the centrifuge, & what to actually test for in experiments.  Dr. Jurist suggested that starting with 1/6th lunar gravity made sense because if it was sufficient, we would know that anything stronger than 1/6th would work.  If not, we should probably next experiment with Martian gravity which is about 1/3rd Earth gravity.

In our second segment, Dr. Jurist referred to his talking points which you will find on The Space Show blog. We went line by line so follow along with us.  Despite interruptions, John stayed on topic with the talking points.  Listener questions asked about how gravity & having a load on bones works & what happens in space when that load is no longer present.  We talked about the time prescription as well as the load factor (G force).  Toward the end, John told us about a reviewed radiation article from 2010 showing that radiation impacted bone loss so the issue in space is more complex than just microgravity.  Near the end, John got a question asking about ETs & their thin, pencil like shape making them perfectly designed for microgravity.  This was both an interesting & fun discussion, bordering on science fiction.  Another question asked about fish, reptilian, sea mammal, & bird bones.  Our final topic dealt with the release of personal astronaut medical information & others & the ways for private information to be legally released to the public.

Please post your comments/questions on The Space Show blog URL above.  Email for Dr. Jurist can be sent to me for forwarding.

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Dr. John Jurist Bisphosphonate Talking Points:

Bisphosphonate show Tues 8:00-9:30 MDT Talking Points

Introduction:             Bone is incredibly complex with many inter-related factorsGoal:                          Brief outline of cellular, structural, and functional aspects of bone metabolism in order to help listeners better understand and appreciate the potential role of bisphosphonates (which is the subject of a future show)

Bone Function:          Two types of bone – compact and trabecular: Compact is outer shell, very dense, and fairly strong

Trabecular – also called spongy, contains spicules, plates, and struts of bone tissue with lots of vascular and fatty marrow, called trabecular

Remodeling:             Bone is constantly being turned over or remodeled with portions being torn down and constituents dumped into bloodstream and other portions being built up from nutrients supplied by blood

Very rapid bone loss can lead to kidney stone formation from calcium dumped into blood

Turnover rate and the volume of total skeleton undergoing remodeling at any given time tends to go down with increasing age (remember this – important)

Balance between formation and resorption (tearing down) also tends to be lost after about age 30, lack of activity, certain hormonal imbalances, diseases, etc. with resorption predominating – one rationale for estrogen replacement therapy after menopause

Coordination between formation and resorption partly controlled by mechanical strains on bone tissue (called Wolff’s Law and issue in microgravity) – some evidence that mechanism is electrical in nature – rationale for electric and electromagnetic bone growth stimulators used to treat problematic fractures and improve incorporation of bone grafts

Cells:                          Stem cells differentiate (or specialize) into osteoprogenitor cells which differentiate into osteoblasts which are the bone formers

Osteoblasts create and secrete a protein and polysaccharide matrix called osteoid which is then calcified later to form the stuff we call bone

Interference in that calcification leads to rickets in children and osteomalacia (Greek for soft bones) in adults

Osteomalacia is often a result of interference in Vitamin D metabolism or dietary deficiencies

During bone formation, some osteoblasts “paint” themselves into a corner and get surrounded by bone – they are then called osteocytes and somehow maintain bone tissue

If osteocytes die in a volume of bone, that devitalized bone no longer undergoes remodeling but can eventually be replaced by a process called creeping substitution (remember comment about remodeling volume going down with age)

Devitalized bone can accumulate fatigue defects and eventually suffer fatigue fractures (called stress fractures – common in military recruits and deconditioned people who recondition too rapidly) if the defects are not replaced by new bone during creeping substitution

Other cells, with multiple nuclei and called osteoclasts, differentiate from marrow cells (monocytes and macrophages) which in turn differentiate from stem cells

Osteoclasts are the bone resorbers and destroyers

Autoradiographic studies show that their nuclei also came from osteocytes as well – presumably as they are resorbed during bone destruction process

Osteoclasts are related to multinucleated “giant cells” which are associated with inflammation in ways I do not understand

Bisphosphonates:      Used over past 20-30 years in clinical medicine – brands include Actonel, Boniva, Fosamax, Aredia, etc.

Multiple mechanisms with different dose-response properties results in clinicians juggling doses and brands to get effects they want without effects they do not want

Bind to hydroxyapatite – the mineralized  portion of bone tissue (calcified osteoid)

Inhibit bone resorption by inhibiting osteoclastic activity

Inhibition of resorption signals osteoblasts to slow down formation rates after a delay (but increases their lifetimes (anti-apotosis)

Bisphosphonates also inhibit mineralization of osteoid – especially at higher doses

That eventually reduces turnover rate and can lead to fatigue fractures with prolonged treatment (remember to call 1-800-BAD-DRUG)

Orthopedic surgeon (Frost atHenryFordHospital) figured out that cyclic therapy exploits delay in osteoblast inhibition relative to osteoclast activity and results in better bone mass gains

Bisphosphonates used in oncology to preserve bone and reduce pathological fractures with osteolytic tumors such as breast and prostate cancers.  Also to counter hormonal blocking therapy used for prostate and breast cancers, but side effects increase with duration of treatment

Interesting sidelight with oncology is some evidence that bisphosphonates reduce risk of tumor metastasis to bone and other sites (somehow involving same signaling pathway as giant cells?)

Oral bisphosphonates cause stomach upset – advise staying upright for an hour or two after taking pill – how does this affect microgravity exposure?

Intravenous bisphosphonates get around oral gastric upset, but placing line or port has risks too (most oncology patients have ports during active treatment)

Also cause osteonecrosis – especially jaw which I believe is septic or infective – and atrial fibrillation (talk to Bill Rowe on this one since he is interested in heart physiology in space)

Bone quality:             Turnover rates and percent of skeleton not devitalized important factors in determining bone strength – measuring bone mass by DEXA or other means is not the be all and end all in evaluating bone strength and risk of fracture.

My Goal:                   General background on bone physiology and function to aid in appreciating upcoming show(s) on bisphosphonates in space medicine

John Batchelor “Hotel Mars,” Wednesday, 12-7-11 December 8, 2011

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John Batchelor “Hotel Mars,” Wednesday, 12-7-11

This segment features Mr. Batchelor,  Dr.Space and Dr. John Jurist discussing bone loss in space

http://archived.thespaceshow.com/shows/1668-BWB-2011-12-07.mp3

Guests:  John Batchelor, Dr. David Livingston, Dr. John Jurist.  Topics:  Bone loss issues for short and long duration spaceflight.  You are invited to comment, ask questions, and discuss the Space Show program/guest(s) on the Space Show blog, https://thespaceshow.wordpress.com.  Comments, questions, and any discussion must be relevant and applicable to Space Show programming. Transcripts of Space Show programs are not permitted without prior written consent from The Space Show (even if for personal use) & are a violation of the Space Show copyright. The Space Show/OGLF is now engaged in its annual fundraising drive. Please see & act upon our appeal at https://thespaceshow.wordpress.com/2011/11/21/space-show-2011-fundraising-campaign.  As many of you know, I have been doing a weekly segment on the John Batchelor Radio Show with Mr. Batchelor on various space topics.  Sometimes I appear with John as the only guest on the segment, at other times I co-host the segment with John and bring on board an expert in the subject being discussed. Mr. Batchelor has given The Space Show permission for these segments to be archived on The Space Show site and blog.  Mr. Batchelor calls these segments “Hotel Mars” and they are targeted toward his significant live and podcast highly educated general audience.  Find out more about the excellent John Batchelor Show and listen to his archived segments at http://johnbatchelorshow.com.  You can hear the live stream of his show if it is not carried live in your radio market at www.wabcradio.com/article.asp?id=531472.  For this segment of Hotel Mars, we discussed bone loss in space and the use of the class of drugs known as bisphosphonates in treating bone loss issues.  This discussion was prompted by various news reports such as this one:  www.dispatch.com/content/stories/national_world/2011/12/06/osteoporosis-drugs-helped-astronauts-scientists-say.html.  Our special guest was Dr. John Jurist and I co-hosted the segment with Mr. Batchelor.  During our eleven minute segment, we addressed bone loss issues for both short duration and long duration spaceflight.  We talked about the use of bisphosphonates, the benefits and the risks associated with them.  We also addressed artificial gravity, issues of both lunar and Martian gravity, and the seriousness of the bone loss issue as well as the other human factors issues primarily for the longer duration voyages.  Post any comments/questions that you might have regarding this John Batchelor Show segment on The Space Show blog URL above.  We thank Mr. Batchelor for allowing us to archive this segment on The Space Show website and blog.  Please note that the copyright to this material remains with The John Batchelor Show.  Any and all uses of this material must be approved by John Batchelor.