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Investigation of the cause of death during diving is one of the contents of forensic pathology. In this article, relevant foreign literature is reviewed to summarize the techniques and methods used in the identification of diving deaths, such as accident reconstruction, diving monitoring data, postmortem CT examination and gas analysis (location and quantity) in the body of the corpse, in order to provide a reference for forensic identification of such cases.
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Humans , Autopsy/methods , Diving , Forensic Medicine , Forensic Pathology , Postmortem ChangesABSTRACT
Objective To investigate the dietary and nutritional status of submarine crew, and to provide guides for reasonable diet and reference for seting new food standards for military personal. Methods During submarine docking, 100 submarine crew were selected as subjects. A total of 100 questionnaires were sent out and 96 valid questionnaires were collected, with an effective rate of 96.0%. The dietary survey was carried out for 4 consecutive days by weighing method. The daily energy consumption of the crew was measured by 24-hour life observation method, meanwhile the body mass index (BMI) and body fat rate were also measured. The common nutritional deficiency symptoms and suggestions on food supply were evaluated by the questionnaire. Results The survey showed that the food intakes, such as cereals, soybean, vegetables, poultry, milk, fish and shrimp, were insufficient, while the intakes of livestock meat and vegetable oil were above the military standard. Their daily energy intakes were higher than the military standard requirements and could meet the energy consumption; the protein and fat energy supply ratios were too high, while that of carbohydrate was too low. The intakes of sodium, iron, phosphorus and vitamin E were all over the standard, while the intakes of iodine, vitamin A and B vitamins were insufficient. Physical investigation showed that overweight and obesity was 46.8% (36/77), and slightly higher and high body fat rate was 48.1% (37/77). In addition, the incidences of nutritional deficiency symptoms, such as dry eyes, bleeding gums, and mouth and tongue ulcers were 26.0% (25/96), 22.9% (22/96) and 19.8% (19/96), respectively. Fruits, dairy products, beef and mutton were the top three recommended food to be increased for the crew's food supply. Conclusion The submarine crew have an unreasonable dietary structure, inappropriate energy supply of the three major nutrients, and unbalanced nutrient intakes. It is necessary to adjust the dietary structure and improve the diet pattern so as to promote the crew's health..
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A standardized neurocognitive test battery is needed to study the effects of military isolated and confined environments on the cognitive functions of personnel. The cognitive tests currently in use have the following problems: inconsistency among different studies, no clear psychological processes, the presence of practice effect, absence of related normative data, and insufficiency in sensitivity, difficulty, and comprehensiveness. Therefore it is proposed that the neurocognitive tests for military isolated and confined environments should meet the following requirements: (1) easy to carry and easy to carry out the test; (2) the test time should be as short as possible (≤30 min); (3) suitable for repeated measuring, and the subjects can reach a stable level quickly; (4) preferably a complete set of test, the cognitive function should be comprehensively and should be closely related to specific tasks; (5) the test should be based on the norm of military isolated and confined environments and the changing curve with time, which can be used as controls; (6) the reliability and validity of the cognitive test should have been tested; (7) with high sensitivity and appropriate test difficulty; (8) the psychological process involved in the cognitive test is clear and simple, making it easy for result interpretation; and (9) the brain areas activated by cognitive test should be clear, which is convenient for further neuropsychological research. Cognition, American National Aeronautics and Space Administration (NASA) neurocognitive test battery for spaceflight, almost perfectly fits the above nine requirements. In the future when our army develops the neurocognitive test tools based on NASA Cognition, we should emphasize the following four focuses: improving the portability of the cognitive test device, developing computerized adaptive cognitive tests, clarifying the inclusion criteria of cognitive tests, and developing parallel tests with consistent psychometrics characteristics.
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OBJECTIVE: To develop a diagnostic model for superficial soft tissue lesions to differentiate epidermal cyst (EC) from other lesions based on ultrasound (US) features. MATERIALS AND METHODS: This retrospective study included 205 patients who had undergone US examinations for superficial soft tissue lesions and subsequent surgical excision. The study population was divided into the derivation set (n = 112) and validation set (n = 93) according to the imaging date. The following US features were analyzed to determine those that could discriminate EC from other lesions: more-than-half-depth involvement of the dermal layer, “submarine sign” (focal projection of the hypoechoic portion to the epidermis), posterior acoustic enhancement, posterior wall enhancement, morphology, shape, echogenicity, vascularity, and perilesional fat change. Using multivariable logistic regression, a diagnostic model was constructed and visualized as a nomogram. The performance of the diagnostic model was assessed by calculating the area under the curve (AUC) of the receiver operating characteristic curve and calibration plot in both the derivation and validation sets. RESULTS: More-than-half-depth involvement of the dermal layer (odds ratio [OR] = 3.35; p = 0.051), “submarine sign” (OR = 12.2; p < 0.001), and morphology (OR = 5.44; p = 0.002) were features that outweighed the others when diagnosing EC. The diagnostic model based on these features showed good discrimination ability in both the derivation set (AUC = 0.888, 95% confidence interval [95% CI] = 0.825–0.950) and validation set (AUC = 0.902, 95% CI = 0.832–0.972). CONCLUSION: More-than-half-depth of involvement of the dermal layer, “submarine sign,” and morphology are relatively better US features than the others for diagnosing EC.
Subject(s)
Humans , Acoustics , Calibration , Discrimination, Psychological , Epidermal Cyst , Logistic Models , Nomograms , Retrospective Studies , ROC Curve , UltrasonographyABSTRACT
Objective: To investigate the effects of submarine environment on the comprehension, memory and job performance of submariners through a comparative study. Methods: A cluster sampling method was used to select 141 submarine crew members from a submarine detachment, and 159 off-shore crew members from a submarine base were taken as the controls. The comprehension capability was examined with comprehension testing subscale of Wechsler adult intelligence scale-Chinese revised in the two groups, and the memory capability was examined with picture arrangement subscale of Wechsler memory scale-Chinese revised. The job performance was evaluated by hand coordination tester and finger flexity tester, and the results were compared between the two groups. Results: Comprehension test showed that the comprehension ability of submariners with a more than 5 years service experience was significantly lower than that of off-shore counterparts (t=4.67, P<0.01). In hand coordination test, the out track times were significantly more in submariners with a 3-5 and more than 5 years service experience than those in off-shore counterparts (Z= - 2.20, P<0.05; Z= - 2.21, P<0.05). In finger flexity test, the out track times was significantly more in submariners with a 3-5 and more than 5 years service experience than those in off-shore counterparts (Z= - 3.08, P<0.01; Z= - 4.52, P<0.01). Conclusion: Comprehension ability and job performance of submariners are lower than those of off-shore counterparts. Comprehension ability of submariners with a more than 5 years service experience is worse than that of off-shore counterparts. Job performance of submariners with a 3-5 or more than 5 years service experience is worse than that of off-shore counterpart. The submarine environment has no obvious influence on memory of submariners.
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On-shore port-based training is important to improve naval submarine rescue and escape capability. It is highly necessary to establish subordinate comprehensive training base for submarine rescue and escape, so as to solve the current problems in on-shore port training. Taking into consideration of the organizational leadership, coordination mechanism, supporting system, operational mode, main function, role design, numbers and location of setting, and supplementary measures, we put forward a general concept for the training base, hoping to provide ideas for innovating the training mechanism and improving the training effectiveness of naval submarine rescue and escape capability.
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Objective To explore the application of asymmetric kinetics of physiological inert gases in diving decompression algorithm.Methods Considering that the actual desaturation in the human body was slower than the saturation process,the kinetic equations of different saturation and desaturation rate of inert gases were constructed with piecewise functions on the basis of the original single exponential kinetic equation.The results were compared other adjustment methods.Results With the application of asymmetric kinetics, the time at each decompression stop was prolonged for an approximately equal proportion, remained unchanged at some deeper and shorter stops.Conclusion Asymmetric kinetics can more closely simulate the gas movement in the body to effectively control the conservativeness of decompression,and adapt to different decompression requirements by adjusting the half-saturation time ratio.
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Object To execute medical information informatized acquisition, transmission, storage and procession to facilitate the submarine medical rescue team to implement medical treatment on the rescue ship.Methods A submarine rescue medical information system based on information and material flows was developed with PowerBuilder 11.5 platform, C/S architecture and Oracle 11g database, which was composed of six modules of personnel management, equipment management, drug and consumables management, examination and evaluation, medical treatment and system management. In medical treatment module information sharing and real-time communication were implemented between the groups of casualty triage, casualty holding, surgical treatment and severe injury treatment.Results The system realized information acquisition, procession, application and integrated sharing during mass casualty treatment on the rescue ship.Conclusion The system enhances the military hospital in medical support to multi military missions, medical commanding and comprehensive treatment.
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Objective To optimize the application principles of gradient factors(GFs) in decompression algorithm by analyzing its law of regulation.Methods The saturated value of compartments was listed and the limits of decompression were calculated to evaluate the effect of GFs on safety and efficiency of decompression.The anchor point of GFs was changed.Results and Conclusion A higher GF was recommended in shallow and short dives, while in deep and long dives a moderate low GF and decompression by oxygen was preferred.The modification of the anchor points of GFs can increase the risk of decompression sickness and should be used with caution.
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Objective To investigate the distribution and changes of microorganisms on the skin of submariners under a chronically closed environment , and provide reference for targeted medical support .Methods One hundred and twenty-two samples were collected using swab.After culture and isolation, the microbes were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry ( MALDI-TOF-MS) .Results A total of 52 types of 229 bacteria and 2 types of fungi were isolated . Major opportunistic pathogens included Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter cloacae, while major dwelling bacteria included Micrococcus luteus, Oslo Mora bacteria, Acinetobacter, Staphylococcus epidermidis, and Serratia marcescens.Compared with the early period of the task, major opportunistic pathogens and dwelling bacteria were significantly increased in the middle and late period of the task .Conclusion The skin microbes of the submariners are investigated , targeted drugs need to be prepared for daily medical support and war trauma .
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Objective To establish a safety culture scale for conventional submarine troops and to analyze the key factors influencing the safety during peace time, so as to provide evidence for future study. Methods Twenty-five items from relative scales were sorted based on a literature review, and 21 of them were included in the final safety questionnaire after extensive analysis and review. A total of 180 submariners were surveyed with the questionnaire, and the effective response rate was 81. 67% (147) and their data were used for further analysis. Results Thirty-two (21. 77%) responders have experienced a safety incidence, and 12 (8. 16%) had been injured due to the incidences. Four dimensions of the safety culture for the target population were indentified by exploratory factor analysis, including commitment to safety by the decision-makers, satisfaction degree of safety effort, priority of safety effort, and communication on safety, which could explain 71. 532% of the variance. The Cronbach’s α was calculated for each scale (all over 0. 7). indicating satisfactory internal consistency for this measurement. Conclusion High incidence of safety events and injury rate of the participants from submarine troop demand more efforts on safety. Submariners are different from other seafarers in civil groups. They are trained to be obedient to orders and leadership, aware of the importance of missions; on the other hand they have stronger self-consciousness and they are not satisfied with simple emphasis on safety and repeated education. However, they are not active in reporting safety issues to the superiors, so the safety culture among them needs to be improved.
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Objective To investigate the effects of submarine environment on the ability of attention focusing and distribution of submariners through a comparative study. Methods To measure simple reaction time, complex reaction time, correct times of reaction, the time on targets as well as the times out of track with attention focus measuring instrument (EP701C) and attention distribution measuring instrument(EP708A). Results In the attention focusing test, the times out of track of target was significantly more in submariners with a 3-5 years service experience compared with their off-shore counterparts(t=2.03,P<0.05). The time on targets was significantly shorter in submariners with a more than 5 years service experience compared with their off-shore counterparts(t=2.27,P<0.05), and the times out of track of target was significantly more in submariners (t=2.12,P<0.05). In the attention distribution test, the correct times of reaction in submariners with 3-5 years service was significantly less than their off-shore counterparts(Z=7.03,P<0.01), and the same was also true for those with a more than 5 years service experience(Z=7.74,P<0.01). Conclusion Our findings indicate that the attention abilities of submariners are lower than those of off-shore staffs, and 3-5 year service period is the important time for impairment of attention ability among submariners.
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Hyperbaric oxygen has been widely used in the treatment of many diseases and in some special circumstances such as deepwater diving, and it plays an irreplaceable role. But oxygen toxicity is an important complication, especially in diving medicine. Due to the characteristics of lung itself and the differences in dry/wet environment, the pathological mechanism of pulmonary oxygen toxicity is very complicated. With the advances in the experimental techniques and expansion of the research ideas, the studies on pulmonary oxygen toxicity have no longer limited to the level of tissue morphology and pathological strata, more and more studies that focused on cellular and sub-cellular levels have been carried out. The present review will focus mainly on the clinical manifestations, pathophysiology, pathogenesis and progresses in monitoring and treatment of pulmonary oxygen toxicity over recent years.
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Objective To study the effect of different regulation modes of the air in cabin on the arterial blood gas of mariners during a prolonged voyage in a nuclear submarine. Methods During three long distance voyages of the same nuclear submarine, the same air-regeneration device was adopted. According to the different doses and percentages of the oxygen-lithium hydroxide absorbers, the mariners of three voyages were divided by sequence of voyages into control group (C), observation group 1 (A), and observation group 2 (B). The change in arterial blood PaO2 and PaCO2 of mariners in the three groups were detected on the third day of surface navigation (T1), 10th day (T2), 12nd day (T3), 13th day (T4) of submarine navigation, and the day before returning (T5). Result There was no difference between the three groups in T1 and T2 (P>0.05). There was a significant difference in PaO2 and PaCO2 between the two observation groups and the control group on T3, T4 and T5 (P<0.05). Conclusions Different amount and percentage of the oxygenlithium hydroxide showed an influence on PaO2 and PaCO2 of the mariners. Optimal amount and percentage of the oxygen-lithium hydroxide is very important in keeping normal physiological status of mariners in a nuclear submarine.
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Objective To evaluate the effect of military performance stress on the changes of concentrations in salivary chromogranin A ( CgA) ,β-endorphin (β-EP) and salivary IgA ( sIgA) of submariners.Methods Twenty-nine submarine soldiers were selected, and their saliva samples were collected separately at the end of a long dive trip and nine months after relaxation ashore.In addition,the saliva samples of twenty-eight graduate students were collected as the normal control.The method of ELISA was used to detect the level of salivary CgA,β-EP and sIgA.Results After long-term dive training, the submariners showed significantly decreased CgA,β-EP and sIgA.Conclusion After a long term dive trip, chronic military performance stress is associated with the decline of salivary CgA,β-EP and sIgA, indicating that the function of sympathet-ic adrenal medulla is suppressed.The biological significance of these changes needs to be assessed in the future.
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Objective To investigate the correlation between the types of constitution in TCM and the sleep status in the PLA Navy divers. Methods Eighty-nine PLA Navy divers who performed 10m diving professional training were selected. Constitution in TCM was classified and determined by the standardized standard Constitution in Chinese Medicine Questionnaire, sleep status was evaluated by the Pittsburgh Sleep Quality Index. Results 62.9% of Navy divers were the mild constitution in TCM. The eight kinds of the biased constitution in TCM are ranked with yang deficiency, phlegm-dampness, dampness-heat, qi deficiency, yin deficiency, blood stasis, qi stagnation and special intrinsic quality. Among 78 Navy divers with good sleep quality, there were 49 divers (72.1%) with the mild constitution in TCM and 19 (27.9%) with the biased constitution in TCM. Among 21 Navy divers with poor sleep quality, there were 7 divers (33.3%) with the mild constitution in TCM (accounting for) and 14 (66.7%) with the biased constitution in TCM. For Navy divers with poor sleep quality, the sleep quality scores were positive correlated with the blood stasis constitution in TCM (r=0.481,P<0.05). Conclusion Sleep status is correlated with the types of the constitution in TCM, and regulating constitution in TCM can improve sleep quality in PLA Navy divers.
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Objective To investigate the significance of salivary cortisol , dehydroepiandrosterone sulfate (DHEA-S) and cortisol/DHEA-S ratio changes for evaluation of military performance stress .Methods Forty submarine soldiers were selected, whose saliva samples were collected separately at the end of long-term dive training and after nine months of relaxation break.In addition, the saliva samples of thirty-four graduate students were collected the moment they finished a three-hour final examination and one week later .The method of ELISA was used to detect the levels of salivary cortisol and DHEA-S and to count their ratio .Results After long-term dive training , the submarine soldiers showed significantly decreased DHEA-S and an increased cortisol/DHEA-S ratio, but the cortisol level did not change very much .In contrast, the final examination stress did not change the level of cortisol , DHEA-S or the cortisol/DHEA-S ratio among these students.Conclusion This is the first study to show that long-term, chronic military performance stress is associated with the salivary DHEA-S and cortisol/DHEA-S ratio changes .The increase in the cortisol/DHEA-S ratio may be used as an important and useful biomarker to evaluate chronic stress .In addition , it is relatively simple and sensitive to detect stress biomarkers by using saliva samples .
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Objective To optimize the constitutionsof the rescue process and medical support teams for submarine rescue, so as to provide new method for evaluating the medical service performance. Methods Using the MedModel software, we established the simulation model of rescue process according to the constitution and work flow for submarine rescue and five ways of getting out of thewater. The mean waiting time of 5 ways was calculated. Results According to the ways of getting out of water, the mean waiting time of each way were calculated and the allocation of medical resources were optimized, making the total waiting time meeting the need of medical rescue team. Conclusion This paper optimizes the rescue process and constitution of the rescue team, saving the medical resources, reducing the total waiting time of the wounded, and providing a new method for evaluating medical serves.
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Os sistemas de disposição oceânica de esgotos domésticos, ou emissários submarinos, têm sido historicamente utilizados em todo o mundo como solução para destinação final de efluentes urbanos, principalmente devido aos aspectos econômicos.Porém, o descarte no oceano, seja em águas rasas ou mais profundas, pode induzir uma série de impactos ambientais negativos, dos quais se destacam a eutrofização, a floração de algas tóxicas, a introdução de microrganismos patogênicos e a contaminação por substâncias químicas capazes de produzir efeitos tóxicos sobre a biota e bioacumulação. Desse modo, o lançamento de esgoto não tratado no mar não constitui uma prática ambientalmente adequada, sendo necessário o tratamento dos efluentes de forma a remover nutrientes, contaminantes e organismos patogênicos e evitar a degradação ambiental.
Oceanic disposal systems of domestic sewage, or submarine sewage outfalls, have been historically used around the world as a solution for urban effluents, in special due to economic aspects. However, release into the ocean, in shallow or deepwaters, may induce a set of negative environmental impacts, as eutrophication, toxic algal blooms, pathogenic microorganisms introduction and contamination by chemical substances which are capable of causing toxic effects to the biota and bioaccumulation. Thus, the release of untreated sewage into the sea does not constitute an adequate environmental practice; then, urban effluents should be treated in order to remove nutrients, contaminants and pathogenic organisms and avoid environmental degradation.
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Humans , Environmental Pollution , Public Health , Sewage , Submarine Outfall , Domestic EffluentsABSTRACT
Objective To investigate the factors influencing the interpersonal relationship of the divers undergoing simulating 450-m diving in the Chinese Navy, in order to establish the psychological intervention strategies and evaluate the efficacy of the intervention, so as to provide a theoretical basis for increasing the combat effectiveness of naval forces. Methods Twenty excellent divers taking part in simulating 450-m diving from Navy units were interviewed, and the record of the interview was analyzed to find out their five common behaviors deteriorating the interpersonal relations, the attributional modes when conflicts happened and five commonly used countermeasures. The divers were divided into two groups, the experimental group and control group (10 people for each), and the experimental group was given psychological intervention. By using the sociometric method and Positive and Negative Affect Schedule(PANAS), comparison was made between experimental group and control group, and also between the pre-intervention status and the post-intervention status of each group. Results All the scores, including social distance (t=-2.61, P=0.03), index of individual social distance (t=-4.83, P=0.00) and negative emotion of PANAS (t=-0.38, P=0.03), were lower in the experimental group than in the control group, and in the experimental group these scores after the intervention were also lower than those before intervention. Conclusions Group psychological intervention has substantial effects on improving the divers' communication skills and satisfaction in interpersonal relationship. This kind of intervention can produce more positive emotion and reduce negative emotion, thus can be popularized in the Navy.