Prediction of signs/symptoms of decompression sickness following submarine tower escape

2019 ◽  
pp. 17-33
Author(s):  
Joel Edney ◽  
Geoffrey Loveman ◽  
Fiona Seddon ◽  
Julian Thacker ◽  
Karen Jurd ◽  
...  
Keyword(s):  
Body Mass ◽  
Marked Effect ◽  
Decompression Sickness ◽  
Outcome Data ◽  
Calibration Data ◽  
Limb Pain ◽  
Pulmonary Barotrauma ◽  
Escape Depth ◽  
Different Types ◽  
Risk Curves

Crew survival in a distressed submarine (DISSUB) scenario may be enhanced by the knowledge of the risks of different types of decompression sickness (DCS) should the crew attempt tower escape. Four models were generated through calibration against DCS outcome data from 3,919 pressure exposures, each for the prediction of one of four categories of DCS: neurological, limb pain, respiratory and cutaneous. The calibration data contained details of human, goat, sheep and pig exposures to raised pressure while breathing air or oxygen/nitrogen mixtures. No exposures had substantial staged decompression or cases of suspected pulmonary barotrauma. DCS risk was scaled between species and with body mass. A parameter was introduced to account for the possibility of the occurrence of some symptom types masking others. The calibrated models were used to estimate likelihood of DCS occurrence for each symptom category following submarine tower escape. Escape depth was found to have a marked effect only on predicted rates of neurological DCS. Saturation at raised internal DISSUB pressure prior to escape was found to affect predicted rates of all symptom types. The iso-risk curves presented are offered as guidance to submarine crews and rescue forces in preparation for, or in the event of, a DISSUB scenario.

scholarly journals Potential Effects of Human Papillomavirus Type Substitution, Superinfection Exclusion and Latency on the Efficacy of the Current L1 Prophylactic Vaccines

Viruses ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 22
Author(s):  
Ian N. Hampson ◽  
Anthony W. Oliver ◽  
Lynne Hampson
Keyword(s):  
Life Cycle ◽  
High Risk ◽  
Outcome Data ◽  
Benign Lesions ◽  
Complex Dynamic ◽  
Papilloma Virus ◽  
Superinfection Exclusion ◽  
Different Types ◽  
Hpv Types ◽  
Type Substitution

There are >200 different types of human papilloma virus (HPV) of which >51 infect genital epithelium, with ~14 of these classed as high-risk being more commonly associated with cervical cancer. During development of the disease, high-risk types have an increased tendency to develop a truncated non-replicative life cycle, whereas low-risk, non-cancer-associated HPV types are either asymptomatic or cause benign lesions completing their full replicative life cycle. HPVs can also be present as non-replicative so-called “latent” infections and they can also show superinfection exclusion, where cells with pre-existing infections with one type cannot be infected with a different HPV type. Thus, the HPV repertoire and replication status present in an individual can form a complex dynamic meta-community which changes with respect to both time and exposure to different HPV types. In light of these considerations, it is not clear how current prophylactic HPV vaccines will affect this system and the potential for iatrogenic outcomes is discussed in light of recent outcome data.

Evaluation of Measurement Uncertainties for Pneumatic Multi-Hole Probes Using a Monte Carlo Method

2016 ◽  
Author(s):  
Magnus Hölle ◽  
Christian Bartsch ◽  
Peter Jeschke
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Compressible Flows ◽  
Uncertainty Evaluation ◽  
Calibration Data ◽  
Input Quantity ◽  
Parameter Evaluation ◽  
Polynomial Curve ◽  
Different Types ◽  
Measurement Uncertainties

The subject of this paper is a statistical method for the accurate evaluation of the uncertainties for pneumatic multi-hole probe measurements. The method can be applied to different types of evaluation algorithms and is suitable for steady flowfield measurements in compressible flows. The evaluation of uncertainties is performed by a Monte Carlo method (MCM), which is based on the statistical law of large numbers. Each input quantity, including calibration and measurement quantities, is randomly varied on the basis of its corresponding probability density function (PDF) and propagated through the deterministic parameter evaluation algorithm. Other than linear Taylor series based uncertainty evaluation methods, MCM features several advantages. On the one hand, MCM does not suffer from lower-order expansion errors and can therefore reproduce nonlinearity effects. On the other hand, different types of PDFs can be assumed for the input quantities and the corresponding coverage intervals can be calculated for any coverage probability. To demonstrate the uncertainty evaluation, a calibration and subsequent measurements in the wake of an airfoil with a 5-hole probe are performed. MCM is applied to different parameter evaluation algorithms. It is found that the MCM approach presented cannot be applied to polynomial curve fits, if the differences between the calibration data and the polynomial curve fits are of the same order of magnitude compared to the calibration uncertainty. Since this method has not yet been used for the evaluation of measurement uncertainties for pneumatic multi-hole probes, the aim of the paper is to present a highly accurate and easy-to-implement uncertainty evaluation method.

scholarly journals Body Mass Index in Human Walking on Different Types of Soil Using Graph Theory

IEEE Access ◽  
2018 ◽  
Vol 6 ◽  
pp. 47935-47942
Author(s):  
Washington Velasquez ◽  
Manuel S. Alvarez-Alvarado ◽  
Joaquin Salvachua
Keyword(s):  
Body Mass Index ◽  
Graph Theory ◽  
Body Mass ◽  
Human Walking ◽  
Different Types

Decompression Sickness Damaging the Spinal Cord in a Scuba Diver: Case Report

1987 ◽  
Vol 3 (2) ◽  
pp. 41-45
Author(s):  
B.G. Mathew
Keyword(s):  
Spinal Cord ◽  
Decompression Sickness ◽  
The United States ◽  
Neurological Involvement ◽  
Detailed Knowledge ◽  
Type I ◽  
Type Ii ◽  
Pulmonary Barotrauma ◽  
Emergency Personnel ◽  
Diving Accidents

Scuba diving has become a popular sport resulting in an increased incidence of diving accidents. A survey done by the United States Navy from 1955 to 1960 revealed that decompression sickness (D.C.S.) is the most common serious complication experienced by scuba divers and the third most likely cause of death. The major cause is drowning and the second is arterial gas embolism from pulmonary barotrauma.D.C.S. has been classified into two groups. Type I includes the less severe forms with bubbles in the skin (“itches”), joints and other tissues. Type II includes the serious conditions with neurological involvement “staggers.” A detailed knowledge of D.C.S., commonly known as “the bends,” is essential to both divers and emergency personnel in order to minimize the morbidity and mortality associated with this condition.A case of Type II bends with spinal cord damage is presented and the condition discussed.

scholarly journals Effects of different types of training on weight loss

2019 ◽  
Vol 72 (9-10) ◽  
pp. 272-279
Author(s):  
Danijel Slavic ◽  
Dea Karaba-Jakovljevic ◽  
Andrea Zubnar ◽  
Borislav Tapavicki ◽  
Tijana Aleksandric ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Metabolic Rate ◽  
Body Mass ◽  
Resting Metabolic Rate ◽  
Young Male ◽  
Fat Free Mass ◽  
Daily Energy Expenditure ◽  
Total Body Mass ◽  
Daily Energy ◽  
Different Types

Introduction. The difference between 24-hour daily energy intake and total daily energy expenditure determines whether we lose or gain weight. The resting metabolic rate is the major component of daily energy expenditure, which depends on many different factors, but also on the level of physical activity. The aim of the study was to determine anthropometric and metabolic parameters of athletes engaged in different types of training, to compare obtained results and to examine whether there are statistically significant differences among them. Material and Methods. The study included a total of 42 young male athletes divided into two groups. The first group included 21 athletes who were predominantly engaged in aerobic type of training, and the other group of 21 athletes in anaerobic type of training. Anthropometric measurements were taken and resting metabolic rate was assessed using the indirect calorimetry method. The results were statistically analyzed and the differences in parameters between the two groups were compared. Results. Statistically significant differences were established in total body mass, amount of fat-free mass and muscle mass, body mass index, as well as in the relative metabolic indices between two groups of subjects. Conclusion. The percentage of fat-free body mass has the greatest impact on the resting metabolic rate. The rate of metabolic activity of this body compartment is higher in athletes engaged in aerobic than in athletes engaged in anaerobic type of training.

scholarly journals Динаміка лейкоцитів крові поросят у різні стресорні періоди онтогенезу при згодовуванні добавок «В-глюкан» та «Біовір»

2017 ◽  
Vol 19 (73) ◽  
pp. 193-197
Author(s):  
V.H. Stoyanovskyi ◽  
O.I. Matsiuk ◽  
V.A. Kolotnyskyy
Keyword(s):  
Body Mass ◽  
Oxygen Transport ◽  
Physiological State ◽  
Vena Cava ◽  
Feed Additives ◽  
Feed Additive ◽  
Transport Function ◽  
Absolute Content ◽  
Hematology Analyzer ◽  
Different Types

The article provides the results of the research of the number of different types of leukocytes in blood of piglets at stress periods of ontogenesis while adding to their ration probiotic feed additives «B-Glukan» and «Biovir». There was formed three groups for conducting the research – Control (K), and two research (D1, D2), with 10 piglets in each group. Starting from 5th to 45th day age, piglets of the D1 group were fed with feed additive «B-Glukan», piglets of D2 group were fed with feed additive «Biovir» with the amount of 10 mg/kg of body mass per day. At the 28th day piglets were separated from sow. The material for the research was blood, which was taken in the morning, before the process of animals feeding, using the method of puncture of cranial vena cava at the 25th day of life (period before separation), at the 29th day of life (1 day after separation), at the 35th day of life (7 days after separation), at the 58th day of life (20 days after separation), at the 88th day of life (60 days after separation). The blood was determined by the absolute content of granulocytes, lymphocytes and monocytes using hematology analyzer MITIKH-18 (Switzerland). It is proven that while adding for D1 and D2 groups of piglets feed additives «B-Glukan» and «Biovir» in amount of 10 gr/kg body mass per day during 5th–45th day age promotes oxygen-transport function of blood, normalization of physiological state of an animals' organism in the period of adaptation to the stress action due to the process of separation, that can show the increase of leukocytes content in blood in 1.9 and 2.6 times (Р < 0.01), owing to granulocytes, lymphocytes and monocytes, in comparison with the animals of K group. Better result at the analysis of experimental material was obtained in piglets of D2 group, which were fed with feed additive «Biovir».

scholarly journals At Odds: Concerns Raised by Using Odds Ratios for Continuous or Common Dichotomous Outcomes in Research on Physical Activity and Obesity

2012 ◽  
Vol 5 (1) ◽  
pp. 13-17 ◽  
Author(s):  
Gina S. Lovasi ◽  
Lindsay J. Underhill ◽  
Darby Jack ◽  
Catherine Richards ◽  
Christopher Weiss ◽  
...  
Keyword(s):  
Body Mass Index ◽  
New York ◽  
Body Mass ◽  
Odds Ratio ◽  
Statistical Power ◽  
Relevant Information ◽  
Outcome Data ◽  
Odds Ratios ◽  
Dichotomous Outcomes ◽  
Prevalence Ratios

Purpose: Research on obesity and the built environment has often featured logistic regression and the corresponding parameter, the odds ratio. Use of odds ratios for common outcomes such obesity may unnecessarily hinder the validity, interpretation, and communication of research findings. Methods: We identified three key issues raised by the use of odds ratios, illustrating them with data on walkability and body mass index from a study of 13,102 New York City residents. Results: First, dichotomization of continuous measures such as body mass index discards theoretically relevant information, reduces statistical power, and amplifies measurement error. Second, odds ratios are systematically higher (further from the null) than prevalence ratios; this inflation is trivial for rare outcomes, but substantial for common outcomes like obesity. Third, odds ratios can lead to incorrect conclusions during tests of interactions. The odds ratio in a particular subgroup might higher simply because the outcome is more common (and the odds ratio inflated) compared with other subgroups. Conclusion: Our recommendations are to take full advantage of continuous outcome data when feasible and to use prevalence ratios in place of odds ratios for common dichotomous outcomes. When odds ratios must be used, authors should document outcome prevalence across exposure groups.

Predicting risk of decompression sickness in humans from outcomes in sheep

1999 ◽  
Vol 86 (6) ◽  
pp. 1920-1929 ◽  
Author(s):  
Robert Ball ◽  
Charles E. Lehner ◽  
Erich C. Parker
Keyword(s):  
Animal Model ◽  
Kinetic Parameters ◽  
Body Mass ◽  
Decompression Sickness ◽  
Compressed Air ◽  
Combined Model ◽  
Scaled Model ◽  
Log Likelihood ◽  
Practical Tool ◽  
Similar Body

In animals, the response to decompression scales as a power of species body mass. Consequently, decompression sickness (DCS) risk in humans should be well predicted from an animal model with a body mass comparable to humans. No-stop decompression outcomes in compressed air and nitrogen-oxygen dives with sheep ( n = 394 dives, 14.5% DCS) and humans ( n = 463 dives, 4.5% DCS) were used with linear-exponential, probabilistic modeling to test this hypothesis. Scaling the response parameters of this model between species (without accounting for body mass), while estimating tissue-compartment kinetic parameters from combined human and sheep data, predicts combined risk better, based on log likelihood, than do separate sheep and human models, a combined model without scaling, and a kinetic-scaled model. These findings provide a practical tool for estimating DCS risk in humans from outcomes in sheep, especially in decompression profiles too risky to test with humans. This model supports the hypothesis that species of similar body mass have similar DCS risk.

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