Chronic Multi-Electrode Electromyography in Snakes

Knowledge about body motion kinematics and underlying muscle contraction dynamics usually derives from electromyographic (EMG) recordings. However, acquisition of such signals in snakes is challenging because electrodes either attached to or implanted beneath the skin may unintentionally be removed by force or friction caused from undulatory motion, thus severely impeding chronic EMG recordings. Here, we present a reliable method for stable subdermal implantation of up to eight bipolar electrodes above the target muscles. The mechanical stability of the inserted electrodes and the overnight coverage of the snake body with a “sleeping bag” ensured the recording of reliable and robust chronic EMG activity. The utility of the technique was verified by daily acquisition of high signal-to-noise activity from all target sites over four consecutive days during stimulus-evoked postural reactions in Amazon tree boas and Western diamondback rattlesnakes. The successful demonstration of the chronic recording suggests that this technique can improve acute experiments by enabling the collection of larger data sets from single individuals.

Thermal property analysis of tri layer composite fabric towards the utility of sleeping bag

Purpose This paper aims to investigate on composite fabrics to develop the improved sleeping bag using trilayered textile structures. A thermal comfort analysis of fabrics is essential to design an enhanced type of sleeping bag. Design/methodology/approach In this study, optimizing thermal and permeability properties of different combinations of trilayer composite fabrics was done. The inner layer was 100% wool-knitted single jersey fabric. The middle layer was polyester needle punched non-woven fabric. The outermost layer was nylon-based Core-Tex branded waterproof breathable fabric. Five variations in wool-knitted samples were developed by changing the loop length and yarn count to optimize the best possible combination. Two different polyester non-woven fabrics have been produced with the changes in bulk density. Twelve trilayer composite fabric samples have been produced, and thermal comfort properties such as thermal conductivity, thermal absorptivity, thermal resistance, air permeability and relative water vapour permeability have been analysed. Findings Among the 12 samples, one optimized sample has been found with the specification of 100% wool with 25 Tex yarn linear density having 4.432-mm loop length inner-layered fabric, 96 g/m2 polyester nonwoven fabric as the middle layer, and 220 g/m2 Nylon-Core tex branded outermost layer. All the functional properties of the composite fabric are significantly different with the knitted wool fabrics and polyester nonwoven fabrics, which have been confirmed by analysis of variance study. Originality/value This research work supports for producing sleeping bag with enhanced comfort level.

Factors influencing thermal resistance of a down sleeping bag

PurposeTo have a better understanding of the heat transfer mechanisms in a sleeping bag and to investigate the factors influencing thermal resistance of a down sleeping bag.Design/methodology/approachThe mechanism of heat transfer in a sleeping bag was discussed in this paper. The thermal resistances of 24 samples were investigated. Besides, the relation between fill weight and thermal resistance, and that between the air permeability of fabric and thermal resistance, as well as that between down filling rate and thermal resistance were analyzed.FindingsThe results showed that thermal resistances of samples varied from 0.35 to 0.8 m2 K/W. The fill weight was the most important factor of thermal resistance of sleeping bag and the relation between fill weight and thermal resistance matched well with cubic function. A multiple regression formula was proposed, which with thermal resistance as a dependent variable and with air permeability of fabric, down filling rate, fill weight as independent variables.Originality/valueThermal properties of a sleeping bag were analyzed through simplified basic unit under simplified environment conditions, which was necessary for building the first stage of systematic study of thermal performance of a sleeping bag.

Survive, Revive, Thrive: Chapter 5: Shakedown Cruise

I am very resourceful, as any woman would be. - Valentina Tereshkova, Russian cosmonaut, born 1937 (first woman in space, Vostok 6, 16 June 1963) What is a Shakedown Cruise? Learning is not compulsory ... neither is survival. - W. Edwards Deming, American engineer, 1900-1993 (His management practices revived Japan.) For those unfamiliar, a “shakedown cruise,” also known as a sea trial, is performed to test a ship’s operational systems, both mechanical and human. I became painfully aware of the term “shakedown” when I went on my first trip to the Charles L. Sommers Canoe Base operated by the Boy Scouts in northern Minnesota in 1974. The guides had us (literally) dump everything out of our travel bags and then selected only the essential items we could take. Weight was at a premium, and, if I may confess, I did lie a little about my age. The minimum age was 12, and I turned 12 during the trip, but it was a brutal physical experience for us. We were left with a compass, a few utensils for eating, a sleeping bag, and one change of clothes. I actually recall drinking, eating, and cooking out of a single stainless steel cup. Bluntly, I don’t think I have ever been colder, hungrier, or more tired in my life. But, of course, the guides were correct. You only need the essentials to survive. Many of you are probably thinking, “I’ll bet I know where he is going with this …,” and you are right. As individuals and as an industry, we need to focus on the essentials. Our industry is on a shakedown cruise like no other in our history. We must jettison the nonessentials and test the machinery (i.e., our technical knowledge and capabilities) as we restart and re-engage. Most importantly, we must focus on those actions/paths that ensure our effectiveness, efficiency, and long-term survival. At SPE, we, too, are in shakedown mode, which has been painful for all and excruciating for some. We have had to redirect resources, and, perhaps most importantly, we have had to focus on the reality that our business model must undergo substantial changes. The essentials will remain, such as technical conferences, workshops, and our primary intellectual asset, technical publications. However, assistance to sections and student chapters has been reduced, as well as support for academic and public service programs. The reality is that SPE is financially sound, but, like any ship in a storm, it has to batten its hatches and, if the pandemic prevails, make further program reductions. On a positive note, SPE has been able to avoid reducing its workforce, as we have created a financial path that avoids personnel reductions. As the 2021 SPE President, I congratulate the SPE’s senior management for their efforts to achieve this outcome.

Can infant sleeping bags be recommended by medical professionals as protection against sudden infant death syndrome?

Clinical scenario: A mother brought her infant to the hospital with bronchiolitis and incidentally asked if I would recommend the use of infant sleeping bags to protect against Sudden Infant Death Syndrome as several of her friends use them. Structured question: Can infant sleeping bags be recommended by medical professionals as protective against Sudden Infant Death Syndrome? Methods: A literature search was performed. Trials were included if they had an English version available and the papers examined the impact that sleeping bag use had on risk of SIDS or its risk factors. Cochrane Library search found eight trials, two of which were found to meet inclusion criteria. MEDLINE was searched using the search terms ((baby sleeping bag) OR infant sleeping bag) OR cotton sleeping sack. Forty-seven papers were found, two of which were found to meet the inclusion criteria, one of which had already been found in the Cochrane Library search. One further paper was found through searching citations of the papers included. Discussion: Sleeping bags are used in 48-95% of infants in the UK and advocated for by the Lullaby Trust for their safety in the prevention of SIDS. The case control studies included found that sleeping bags are as safe, if not safer than other bedding when examining SIDS as an outcome. For sleeping bags to be safe they must be well made and appropriately used, which includes the correct size, Tog, clothing and other bedding for bedroom temperature.