Post-Rifting Magmatism and the Drowned Reefs in the Xisha Archipelago Domain

Fourteen isolated drowned reefs have been identified around the Xisha Uplift by multibeam and seismic data. The drowning processes of these reefs can be divided into three different stages, which correspond to three different accelerated tectonic subsidence periods. The drowning of the Xisha reefs is the result of the combined action of tectonic subsidence and sea level fluctuations, and the tectonic subsidence rate had to remain above 0.2 mm yr^(-1 )for a long time. Three abrupt accelerated tectonic subsidence events that occurred in the late Miocene, Pliocene and early Quaternary in the Xisha Uplift were closely related to the thermal subsidence processes after three stages of post-rifting magmatism. The magmatism of the middle Miocene and the following thermal subsidence resulted in the drowning of reefs in the northwestern Xisha uplift(Zone A). During the early Pliocene, massive magmatic intrusions and volcanic eruptions occurred in the Xisha Uplift. Then, the subsequent thermal subsidence started the drowning process of reefs in the northeastern and western regions of the Xisha Uplift(Zone B and C). During the early Quaternary, large-scale magmatism also occurred in the Xisha Uplift. The subsequent thermal subsidence resulted in a new rapid tectonic subsidence, which caused the reefs in the southern and southeastern regions of the Xisha Uplift to drown(Zone D and E).

Development of a Systematic Review of Public Health Interventions to Prevent Children Drowning

Drowning is the leading cause of death from unintended injury in children globally. Drowning is preventable, and mechanisms exist which can reduce its impact, however the peer-reviewed literature to guide public health interventions is lacking. This paper describes a protocol for a review of drowning prevention interventions for children. Electronic searching will identify relevant peer-reviewed literature describing interventions to prevent child drowning worldwide. Outcome measures will include: drowning rates, water safety behaviour change, knowledge and/or attitude change, water safety policy and legislation, changes to environment and water safety skills. Quality appraisal and data extraction will be independently completed by two researchers using standardised forms recording descriptive and outcome data for each included article. Data analysis and presentation of results will occur after data have been extracted. This review will map the types of interventions being implemented to prevent drowning amongst children and identify gaps within the literature.

The East Japan Great Earthquake and Three Cases of Near-Drowning with Tsunami Due to the Earthquake

We encountered the Great East Japan Earthquake on March 11, 2011. The magnitude of the earthquake is 9.0 and it is one of the greatest from A.D. 1900 to now. The earthquake developed large tsunami and many people living on the pacific coast of east Japan died from lung disorder caused by near drowning with tsunami. We also encountered three cases of lung disorders caused by near drowning. All three were females, and two of them were old elderly. All segments of both lungs were involved in all the three patients, necessitating ICU admission and endotracheal intubation and mechanical ventilation. All three died within three weeks. In at least two cases, misswallowing of oil was suspected from the features noted at the time of the detection. Many bacteria were detected from the phlegm of two cases.

Pollen Findings in a Presumptive Drowning Case

A medicolegal/botanical collaboration has to lead to an interdisciplinary procedure for developing methods when studying dead bodies found in water with no clear circumstances. Hereby we present a report or a preliminary attempt as a basis for encouraging further work in the field. The body of an unidentified 25 - 35 years old woman was found immersed in a fresh water ditch in state of decomposition. Structural alterations avoid any a priori identification of asphyxia or traumatic cervical lesions. The last cause of death was estimated as a cardio respiratory collapse and a drowning investigation was proposed. Taxonomic species identification was carried out to relate the pollen aspiration with the water medium in lung, spleen, liver and water medium. We presented pollen grains in spleen, as a closed organ, as a clue for death investigation in the absence of diatom findings. Information about where and when pollen grains occur may ascertain that a body or an object was in some place at a certain time. Since the consequences of aspiration depend on many factors, such as the quantity, size and solidity of the material aspirated and whether the aspiration is chronically recurrent or acute, the pollen investigation must be done with precaution. We conclude that in the absence of other microscopic structures, biochemical blood analyses, or histological findings, forensic palynology may be of help to relate the presumptive drowned body with its death scenario.

Pulmonary Immunohistochemical Detection of Surfactant Protein A (SP-A) in Fatal Drowning

Drowning still remains one of the most difficult diagnoses in forensic pathology because macroscopic and microscopic autopsy findings are unspecific. An ideal diagnostic marker for drowning still needs to be developed, but some authors have recently studied SP-A as a marker of asphyxiation and drowning. The aim of this study is to compare the histopathological features and the SP-A immunohistochemical expression in lung tissue in the case of drowning with those determined by other causes to discriminate between cadaver submersion and drowning.

Acute and Severe Hypercalcemia in a Near-Drowning Victim

An 80-year-old male was admitted to our hospital because of near-drowning in a hot spring. Besides hypoxia, serum calcium was extremely high at 15.5 mg/dL on admission. After the treatment with normal saline infusion, furosemide and calcitonin, the hypercalcemia was transient and didn’t recur during the course. The hot spring water contained much calcium, so his hypercalcemia was considered to be a result of calcium absorption mainly through the alveoli. In this case, we revealed that serum calcium rose within a short time after drowning, suggesting the necessity to measure the calcium concentration of the drowning fluid in a near-drowning victim.

ECG after near-drowning mimicking acute coronary syndrome with left main coronary artery involvement

We present the case of a 74-year-old man with diabetes and hypertension who had to be rescued owing to a near-drowning syndrome at sea.When he was rescued,he complained of dyspnea and chest pain.An electrocardiogram(ECG)suggested acute coronary syndrome(ACS)affecting the left main coronary artery.Therefore,he was referred to our hospital for urgent coronary angiography.

A sort of iron-manganese nodule developing in drowned platform margin

A sort of purplish red iron-manganese nodules was found in the Middle Ordovician Guniutan-Miaopu period limestone, Anhui Province. About their formational environment, there are two different viewpoints:Yue thought they were deep-water pelagic deposit and Huang et al. believed they were formed inshallow water tide. We think that these nodules were formed in drowned platform margin belonging to atransitional type between shallow-water and deep-water iron-manganese nodules, and different from shoalwater iron-manganese oolites and pelagic iron-manganese nodules in feature and origin. 1 Palaeogeographic setting of iron-manganese nodules

Scedosporium Apiospermum Infection after Near-drowning

Scedosporium apiospermum （S.apiospermum,sexual form of Pseudallescheria boydii） is a highly invasive and opportunistic pathogen.It can invade various organs of the body,causing lethal infections.S.apiospermum is widely distributed in natural environments,including marshes,wetlands,sewage,putrilage,and salt waters.The incidence of S.apiospermum infection can be especially high in humid temperate and subtropical regions.

Postmortem chest computed tomography for the diagnosis of drowning:a feasibility study

It may be difficult to distinguish the cause of death in drowning cases without specific findings.The aim of this study was to explore the forensic value of thoracic postmortem computed tomography(PMCT)using routine images and three-dimensional(3D)image reconstructions.The imaging data of PMCT examinations of six drowning cadavers,aged 21-54years,were analyzed.Twelve victims of sudden death from coronary artery disease(CAD)were chosen as a control group.After 3D bilateral lung images were reconstructed using image processing software,an interactive medical image control system was used to measure and analyze parameters including lung volume,lung volume ratio,mean CT value of the whole lung,and lung CT value distribution curves.Lung volume and lung volume ratio were used to assess the shape changes of the lung.Lung CT value distribution curves showed the corresponding number of pixels of the different CT values in the lung image.Lung volume was not signifi-cantly larger in drowning cases(mean 2958cm^(3))than in controls(mean 2342cm^(3)).Lung vo-lume ratio values in the drowning group(mean 0.3156)were greater than those in the control group(mean 0.2763);(P=0.02).There was no significant difference between the drowning and control group in the mean CT value of the whole lung.There were differences between lung CT value distribution curves in drowning victims and controls,with drowning victims showing a single peak and CAD cases showing a bimodal distribution.Thoracic PMCT is help-ful for the forensic medical diagnosis of drowning.Lung volume ratio and lung CT value distri-bution are potential indicators to distinguish between drowning and CAD.

Bystander resuscitation of a near-drowning child in a rural south China township

We report resuscitation of a near-drowning child by a bystander in a rural south China township.Resuscitation was performed on a 6-year-old,otherwise healthy boy who was witnessed drowning in a river,with submersion for approximately 12 min.Following several resuscitation attempts,spontaneous breathing was established at the scene and the boy was transferred to a nearby hospital.He developed pneumonia but recovered completely on the ward and was discharged without any neurologic disabilities.This case shows that early bystander resuscitation is an important factor for survival after submersion.The search for an ideal approach to resuscitation must continue,and all members of society must work together towards this goal.

Automatic Real-Time Detection of Infant Drowning Using YOLOv5 and Faster R-CNN Models Based on Video Surveillance

Infant drowning has occurred frequently in swimming pools recent years,which motivates the research on automatic real-time detection of the accident.Unlike youths or adults,swimming infants are small in terms of size and motion range,and unable to send out distress signals in emergencies,which exerts negative effects on the detection of drowning.Aiming at this problem,a new step is initialized towards detecting infant drowning automatically and efficiently based on video surveillance.Diverse live-scene videos of infant swimming and drowning are collected from a variety of natatoriums and labeled as datasets.A part of the datasets is downscaled or enlarged to enhance generalization ability of the model.On this basis,advantages of Faster R-CNN and a series of YOLOv5 models are specifically explored to enable fast and accurate detection of infant drowning in real-world.Supervised learning experiments are carried out,model test results show that mean Average Precision(mAP)of either Faster R-CNN or YOLOv5s of the series of YOLOv5 can be over 89%;the former can process merely 6 frames of videos per second with the precision of only 62.04%,while the latter can reach an average speed of 75 frames/s with the precision of about 86.6%.The YOLOv5s eventually stands out as an optimal model for detecting infant drowning in view of comprehensive performance,which is of great application value to reduce the accidents in swimming pools.

Drowning in Illegal Capital

The Chinese Government is cracking down on capital illegally invested in the stock market The Chinese stock market has attracted huge amounts of capital,much of which is speculative or illegal money.

基于改进YOLOv5的溺水人员检测

针对情况复杂而无法实现人员全天全面监管的场所,在实时检测人员防溺水方面存在困难的问题,提出了一种融合统一注意力机制动态头的YOLOv5-Dy-GBCA模型。首先,通过在YOLOv5的Head前引入动态检测头(DyHead),增强头部感知目标的空间位置、尺度和检测任务的能力;其次,将Backbone中的C3模块替换成由GhostBottleneck结构和坐标注意力模块(CA)构成的幻影坐标注意力特征提取模块(GBCA),有效改善了因水上人员相互遮挡、人体在水面浮现体积较少而造成输入的特征语义信息不丰富,特征信息提取不足的问题;然后,引入加权双向特征金字塔网络(BiFPN),增强模型在不同尺度上的特征融合能力;最后,采用Focal-EIoU损失函数,改善难易样本不平衡对检测结果的影响。实验结果表明,YOLOv5-Dy-GBCA模型在维持了原模型检测速度的同时,取得了91.50%的平均精度(mAP),相较于传统算法和其他主流算法检测效果更优。

基于吞咽监测技术的溺水自主救援产品设计研究

目的通过对溺水自主救援产品的再设计,为游泳人群寻找更好的溺水自救途径。方法以溺水者的自主救援需求为导向,运用观察法与情景分析法对溺水者的各种生理表象进行观测、记录及实验比对,确定“呛咳”是有效判断溺水的唯一表象。借助“呛咳”与“吞咽”时喉部肌肉运动方式的一致性,运用吞咽监测技术间接识别“呛咳”的发生,并通过实验验证水下环境中吞咽监测技术识别“呛咳”的可行性。结果溺水状态下的“呛咳”信号呈现特征性变化规律且与正常“呛咳”信号差异显著。结论吞咽监测技术能够准确识别溺水状态,并有效应用于溺水自主救援产品设计中,其提高了溺水者的自救成功率,减少了溺水事故的发生。

面向溺水救援机器人平稳跟踪的模糊比例微分控制视觉伺服方案

针对溺水救援机器人的平稳跟踪需求,提出一种基于模糊比例微分控制的视觉伺服方案,通过场馆顶部安装的俯视摄像头获取机器人的坐标位置,使用虚拟导航线设计动态行走路径,计算偏移方向、偏移角并制定转弯规则;利用三角隶属度函数制定模糊比例、微分控制规则表,根据2种规则表中的比例、微分系数分别控制机器人的偏移角、距离偏移量及其变化率,实现机器人的跟踪与避障的平稳性调整;机器人采用核相关滤波跟踪算法对溺水人员进行跟踪,在溺水人员位置变化时调整运动方向,依靠实时、稳定的声呐信息设置偏移角,实现避障功能;对所提出的方案在先锋P3DX型机器人上进行实验验证。结果表明:机器人能及时应对目标变化,没有跟错、跟丢现象;在不同工况时的横滚角均小于1°,避障率达到100%,能够快速、稳定、准确地到达目标位置,达到溺水救援机器人的前期应用要求。

下扬子地区早二叠世末期碳酸盐台地死亡事件的沉积学与碳同位素记录

华南板块在早二叠世时期位于赤道附近,发育了以栖霞组为代表的浅海碳酸盐岩,随后被孤峰组黑色页岩和硅质岩所取代,代表一次碳酸盐台地死亡事件。文章对下扬子区安徽巢湖平顶山剖面和江苏句容正盘山剖面上栖霞组与孤峰组进行了系统的沉积微相、碳同位素地层学等研究,试图探讨早二叠世末期栖霞组碳酸盐台地死亡的机制。分析表明,栖霞组顶部可划分为9种微相,属于碳酸盐内缓坡—中缓坡沉积环境;孤峰组底部可划分为5种岩相,属于深水盆地环境。栖霞组与孤峰组界处沉积环境和古水深发生突变,代表了下扬子地区早二叠世末期的碳酸盐台地死亡。栖霞组与孤峰组之间的碳酸钙含量突然降低、碳酸盐碳同位素快速负偏、有机质碳同位素明显正偏,指示碳酸盐台地死亡的突发性和事件性。观察显示,无机碳δ^(13)C_(carb)与有机质δ^(13)C_(org)存在镜像关系。文章认为,导致有机和无机碳解耦的原因可能与陆源有机质输入有关,而碳酸盐台地死亡可能为相对海平面上升所导致。

秦皇岛地区基于Utstein模式溺水数据库的建立及相关因素分析

目的通过建立基于心肺复苏乌斯坦因(Utstein)评估模式的溺水数据库,分析秦皇岛地区溺水者的临床特征及影响溺水者存活的关键因素,为溺水急救和治疗提供更有针对性的策略和方法。方法选取2019年6月—2022年11月秦皇岛地区医院收治的108例溺水者,收集溺水者的一般临床资料,包括性别、年龄、溺水类型、既往病史、溺水者初始情况、急救人员是否心肺复苏、首次急救医疗服务(EMS)时间、首次心肺复苏(CPR)时间、现场护理结束(EOSC)时间、意识清醒时间、到达医院是否正在心肺复苏、心肺复苏持续时间、院内心肺复苏类型、生命体征(体温、收缩压、舒张压、心率、呼吸、外周氧饱和度)、院内首次监护心率(室颤、室速、无脉搏新店活动)、初次院内神经系统检查[格拉斯哥昏迷评分(GCS),清醒、言语反应、疼痛反应、无反应评分(AVPU)]、血气[氧分压、二氧化碳分压、pH值、呼气末二氧化碳]、血乳酸水平、气道或通气(无、普通氧气、无创通气、有创通气、非常规有创通气)、肺水肿、自主循环恢复(ROSC)后96 h体温(T_(max)、T_(min))、自主循环恢复(ROSC)后24 h血糖、血糖能否维持、低血压发作(收缩压≤90 mmHg)、持续升压药/正性肌力药支持、溺水并发症(急性呼吸窘迫综合征、弥散性血管内凝血、肺炎、胰腺炎、急性肾损伤、休克、多系统器官衰竭、败血症、电解质紊乱、葡萄糖紊乱)、出院后去向(其他医院、回家、康复疗养院、其他)、出院时情况(脑功能分级、GCS评分、AVPU评分、有无自主呼吸)、院内死亡原因(呼吸窘迫综合征、弥散性血管内凝血、颅内高压、电解质紊乱、急性肾衰竭、癫痫发作、败血症或心肌衰竭)。采用多因素逐步Logistic回归模型分析溺水者存活的危险因素。结果存活组与死亡组的年龄、是否存在既往病史、有无目击者、有无脉搏/心跳、有无呼吸、首次EMS时间、首次CPR时间、EOSC时间、血乳酸水平、有无肺水肿、ROSC后96 h体温T_(max)、ROSC后96 h体温T_(min)、溺水并发急性呼吸窘迫综合征、弥散性血管内凝血、急性肾损伤、休克、多系统器官衰竭、败血症、电解质紊比较,差异均有统计学意义(P<0.05)。多因素逐步Logistic回归分析结果显示,年龄、既往病史、目击者、脉搏/心跳、有无呼吸、首次EMS时间、首次CPR时间、EOSC时间、血乳酸水平、肺水肿、ROSC后96 h体温T_(max)、ROSC后96 h体温T_(min)、溺水并发症均是溺水者存活的影响因素(P<0.05)。基于以上指标构建的列线图预测模型分析显示,其具有较好的区分能力;Bootstrap验证也表明,模型的偏差校准曲线与理想曲线吻合良好。结论本研究基于Utstein评估模式建立的溺水数据库有效地揭示了影响溺水者存活的多种危险因素。这些发现对于提高溺水者的存活率和改善治疗效果具有重要意义。未来的急救和治疗中,需加强对关键影响因素的关注和干预并掌握心肺复苏的重要性。

提升学生溺水高危行为自我控制能力的教育策略研究

溺水高危行为是溺水事故发生的重要前因变量,提升学生溺水高危行为自我控制能力,将有效预防和减少学生溺水高危行为,进而保护学生的生命安全。本文采用文献资料法、访谈法、逻辑分析法等研究方法,总结了溺水高危行为的影响因素,并从行为者本身自我控制资源角度,分析了溺水高危行为自我控制失败的原因:自我游泳能力认知偏差、风险感知能力不足、从众心理的偏离焦虑。据此,提出学生溺水高危行为自我控制能力提升的教育策略:引导学生准确评估自身游泳技能水平,安全知识普及要明确溺水高危行为边界及其危害严重性,通过其他被社会认可的积极冒险行为满足高感觉寻求体验,强化积极型学习群体建设使群体规范指向正向的水域安全态度。

一种基于改进YOLOv7的落水人员检测方法

溺水事故一旦发生,对溺水对象的及时发现并采取积极的相应措施,在减小伤亡后果方面有着至关重要的作用,因此对落水人员的自动监测变得尤为重要。在对野外落水人员目标进行模拟检测的过程中发现,自然水域场景复杂,具有检测目标小、环境干扰大等问题,现有的基准模型YOLOv7的目标漏检率较高。通过在YOLOv7模型的骨干组件中加入ResNet-ACmix,以及在Head部分增加ACmix,从而保留了Backbone采集到的特征,有效提取了复杂场景下的落水人员小目标的特征信息,并增强了模型对落水人员小目标的特征感知和位置信息,降低了水域复杂环境对特征提取的干扰,改进SPPCSPC中的池化部分,保证了落水人员小目标在大场景复杂水域的定位,进一步降低环境干扰,并提升检测速度。在构建的落水人员数据集上进行的各种实验表明,与基线网络的YOLOv7算法相比,改进的YOLOv7平均精度达到80.7%,比原始网络提高了7%。消融实验表明,所设计的模块可以提高检测精度,并能直观地显示不同场景下的检测效果。实验验证了改进YOLOv7在落水人员目标检测中的适用性。