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Plant zonation is one of the most conspicuous ecological features of salt marshes worldwide. In Patagonian salt marshes the cordgrass Spartina alterniflora forms dense monospecific stands along the lowest marsh level, while the higher levels are dominated by Spartina densiflora or Sarcocornia perennis. In this study, we coupled field transplants combined with neighbor exclusion treatments and greenhouse experiments to evaluate the effect of submersion and waterlogged anoxic soil in the determination of the lower distribution limit of S. densiflora in Central Patagonian salt marshes within its native range. In the field experiment, no S. densiflora survived the frequent tidal submersion by approximately 2 m of seawater in the low marsh, independent of the S. alterniflora neighbor's presence, while in the greenhouse experiment, all plants were able to tolerate strongly reducing soil conditions. Our results suggest that the absence of S. densiflora in the low marsh level is a consequence of the effect of the submersion, independent of the presence of S. alterniflora neighbors and of the strong soil anoxia. Our results contribute to optimize the efforts addressed to control or eradicate this exotic species in salt marshes where it is invading. [ABSTRACT FROM AUTHOR]

Injury is common in patients with epilepsy, can have serious consequences (fractures, burns), and can sometimes even be fatal (drowning, vehicular crashes). Seizure-related injuries, drowning, and vehicular crashes have been investigated across differing populations using various methodologies hindering consistent estimates with respect to its frequency, magnitude, and potential risk factors. Knowledge is further complicated by the low incidence of injury outcomes, the not insignificant background frequency of injury in the general population, and the emphasis on seizure-related explanatory mechanisms. Although not without its own complexity, privacy preserving data linkage is an emerging powerful technique that is being increasingly used in epilepsy and other chronic conditions to answer important questions, especially when measuring low incidence health outcomes prospectively, such as injury. This review examines the frequency of overall and specific seizure-related injures, describes the known risk factors and finally suggests future directions for research that may improve our understanding in the area. [ABSTRACT FROM AUTHOR]

There is a direct connection between the breach developed within a dam subjected to an overflow and the resulting flood. A normative model based on statistical studies has been developed in the province of Quebec to initialize the process of the flood: it predicts a breach width four times as long as the breach height and a maximal breach discharge that occurs in 30 min. This norm is applied for all the earth and rockfill dams without any consideration of their own particular characteristics. However, the prediction of the breach's characteristics is still uncertain, which explains that this norm is not over yet and is still the most reliable and secure process to use. A theoretical model is presented in this dissertation predicting the dam failure of the first earth and rockfill dam in Quebec using a bituminous core: Nemiscau-1 dam. Three potential damages have been analysed: potential planes of failure; fracturing of the bituminous core; surface erosion. The results are encouraging: the resulting hydrograph seems to predict the degradation of the dam more precisely and more faithfully than the normative model. The proposed model is more suited for hybrid dams than the safety standards of Hydro-Québec. [ABSTRACT FROM AUTHOR]

Along the southern coast of the North Sea, a large proportion of the Flemish coastal plain consists of densely populated reclaimed land, much of which lying below mean high tide level. This is particularly the case along the northern coast of France, from Dunkirk to the Belgium border, where the shoreline consists of coastal dunes that protect low-lying reclaimed lands from marine flooding. This area is vulnerable and subject to several risks. Extreme weather conditions could induce strong surges that could cause (1) a shoreline retreat, (2) marine submersion and (3) land and/or urban flooding due to drainage problems of the polders. Highly energetic events such as the November 2007 storm could have had much more severe consequences especially if they occurred at high tide and/or during a spring tide. In the current context of global change and projected sea-level rise, it is then important for the local authorities to take into account the potential impacts and return periods of such events, in order to implement coastal risk policies prevention and management, to reinforce sea defense, increase pumping station efficiency and plan warning systems against marine submersion and polder flooding, which is not the case yet in Northern France. [ABSTRACT FROM AUTHOR]

Abstract: The ancient fish tanks and fish traps of Crete are relics of the Roman domination of the island; they were usually constructed near the major urban centers of that period. The direct relationship of their various functional characteristics with past sea levels and the relatively accurate determination of their construction dates establish them as sensitive indicators of sea level change through space and time. The fish tanks presented in detail in this study, namely those of Matala, Chersonissos, Mochlos and Sitia and the fish trap in the gulf of Zakros, have all been reported, recorded and/or interpreted in regard to their operation by previous researchers. In the absence of a comprehensive interdisciplinary approach to the issue, uneven methodologies, inaccurate data and wrong measurements have led to erroneous conclusions about sea level during their operation and about the size and direction of vertical tectonic movements in eastern Crete during the Upper Holocene. The present study is based on a new underwater survey, in the course of which the architectural and functional features of the ancient constructions were reexamined precisely; their depth from modern sea level was measured and their relationship with coastal landforms, indicative of a past sea levels, was investigated. A review of their manner of operation and their modern submerged position allowed the definition of a Roman mean sea level 1.24 m ± 0.09 m below the present one. The submersion of the central and eastern parts of Crete – included in the same tectonic block with a total length of at least 150 km – at an average tectonic rate of 0.65 mm/year during the last 1900 ± 100 years occurred, as is shown by historical evidence, during a paroxysmal tectonic event, probably related to the strong earthquake of 1604. [Copyright &y& Elsevier]

Some small diving beetles can survive submerged through weeks and months, because they can extract oxygen, dissolved in the water, through respiratory pores in their integument. An air flux from the outside to the inside through the respiratory pores has been demonstrated. All diving beetles capable of such pore respiration are small, but not all small diving beetles have pore respiration. With increasing size, more and more of the surface must be covered by respiratory pores to meet the increasing demand of oxygen. In running water species the pore-respiration mode is regarded as an adaptation to life in current exposed substrates, thus they avoid the risk of being swept away during frequent surface visits. In stagnant water species the pore respiration mode reduces the risk of falling victim to pelagic predators. The submersion tolerant species can switch to surface respiration, e.g. during low oxygen content. The pore respiratory mechanism is believed to be a specialised plastron. The oxygen flux through the scattered, small respiratory pore area may be enhanced by a functional thinning of the boundary layer. [ABSTRACT FROM PUBLISHER]

Abstract: Due to the direct relationship between their function and ancient sea levels, Roman fish tanks and fish traps are excellent indicators for sea level changes through time. For this study, eleven submerged systems of fish tanks were investigated along the rocky southern coast of the gulf of Matala, Crete. Seven of them are still in a good state of preservation and thus underwent detailed survey and documentation. The measurements of their recent submersion, the determination of the way they operated, as well as their correlation with coastal landforms indicative of an older sea level, permit the identification of a mean Roman sea level at the SW coast of central Crete 1.25 m below the present one. According to historical evidence, the submersion of the SW coasts of the central part of Crete must have been occurred between 1415 and 1865 during a paroxysmal tectonic event and is probably related with the strong earthquake of 1604. [Copyright &y& Elsevier]

There is an old Chinese proverb that says: "Tell me and I will forget; Teach me and I might remember; Involve me and I will learn." This ancient proverb reflects the state of language retention and restoration. Living in a nation constructed of many diverse cultures provides teachers many unique conditions to their already challenging world of education. For centuries language was taught in the home and today the school is usually the place of language acquisition. Nowadays the two environments should work together to enhance exposure and success. Recently, much attention has been focused on the concept of bilingualism and the role of immersion. More and more of this attention is examining the role of immersion and its preference over the transitional bilingual approach (Kagan, 1990, p. 7). This urges us to carefully consider the impact that instructional media has on government and private schools in Ethiopia, which is a country of diversity in its culture and language. Hence, this research paper, "Instructional Media and its Impact on Government and Private Schools in Ethiopia" attempts to see if there exists any significant difference in the use of English as an instructional medium in both private and government schools and finally tries to perceive the cumulative effect that might happen due this difference. Apart from this, the paper also discusses the use of the vernacular language as medium of instruction and its possible impact on the learners. [ABSTRACT FROM AUTHOR]

Let M be a compact manifold with a symplectic form ω and consider the group $${\mathcal{D}_\omega}$$ consisting of diffeomorphisms that preserve ω. We introduce a Riemannian metric on M which is compatible with ω and use it to define an L-inner product on vector fields on M. Extending by right invariance we get a weak Riemannian metric on $${\mathcal{D}_\omega}$$ . We show that this metric has geodesics which come from integral curves of a smooth vector field on the tangent bundle of $${\mathcal{D}_\omega}$$ . Then, estimating the growth of such geodesics, we show that they extend globally. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The goal of this study was to describe the epidemiology of pediatric submersion events occurring in portable pools in the United States. METHODS: A retrospective analysis of fatal and nonfatal submersion events involving children younger than 12 years in portable pools was conducted using injury and fatality data compiled by the US Consumer Product Safety Commission from 2001 through 2009. RESULTS: There were 209 fatal and 35 nonfatal submersion cases reported to the commission from 2001 through 2009. The majority (94%) involved children younger than 5 years, 56% involved boys, 73% occurred in the child's own yard, and 81% occurred during the summer months. The number of submersion events increased rapidly from 2001 to 2005 and then leveled off from 2005 to 2009. CONCLUSIONS: The use of portable pools in residential settings poses a significant risk of submersion-related morbidity and mortality to children, especially in the <5-year-old age group. No single strategy will prevent all submersion deaths and injuries; therefore, layers of protection are recommended. Industry is advised to engage in development of protective devices that are effective and affordable for portable pools, including isolation fencing, pool alarms, and safety covers. A strong and pervasive consumer education campaign is needed to make consumers aware of the dangers of portable pools, because these small, inexpensive, consumer-installed pools may not generate the same sense of risk as an in-ground pool. [ABSTRACT FROM AUTHOR]

Abstract: There is some confusion, and consequent variation in policy, between the agencies responsible for the search, rescue and resuscitation of submersion victims regarding the likelihood of survival following a period of submersion. The aim of this work was to recommend a decision-making guide for such victims. This guidance was arrived at by a review of the relevant literature and specific case studies, and a “consensus” meeting on the topic. The factors found to be important for determining the possibility of prolonged survival underwater were: water temperature; salinity of water; duration of submersion; and age of the victim. Of these, only water temperature and duration are sufficiently clear to form the basis of guidance in this area. It is concluded that if water temperature is warmer than 6°C, survival/resuscitation is extremely unlikely if submerged longer than 30min. If water temperature is 6°C or below, survival/resuscitation is extremely unlikely if submerged longer than 90min. [Copyright &y& Elsevier]

Plant zonation is one of the most conspicuous ecological features of salt marshes worldwide. In this work we used a combination of field transplant and greenhouse experiments to evaluate the importance of interspecific interactions and physical stress in the determination of the major plant zonation patterns in Central Patagonian salt marshes. There, Spartina alterniflora dominates the low marsh, and Sarcocornia perennis the high marsh. We addressed two questions: (i) What prevents Spartina alterniflora from colonizing the Sarcocornia perennis-dominated high marsh zone? and (ii) What prevents Sarcocornia perennis from colonizing the Spartina alterniflora-dominated low marsh zone? Our experimental transplants combined with neighbour exclusion treatments showed that the presence of Sarcocornia perennis negatively affects Spartina alterniflora, preventing it from surviving and/or spreading. Complementary field transplant and greenhouse experiments showed that Sarcocornia perennis did not survive the frequent tidal submersion by approximately 1.5 m of turbid seawater in the Spartina alterniflora zone, but its survival was independent of the presence of Spartina neighbours, and of the strong soil anoxia as well. Our results suggest that Spartina alterniflora is excluded by Sarcocornia perennis towards the low marsh, where frequent and prolonged submersion limit the survival of the latter. We provide and discuss key baseline information to facilitate the future design of ecophysiological experiments designed to accurately identify the exact mechanisms acting in every situation. [ABSTRACT FROM AUTHOR]

The article focuses on changing sea levels in Venice, Italy, during the 18th century by examining and comparing landscape paintings depicting Venice and drawn with the aid of camera obscuras by painters such as Antonio Canal, also known as Canaletto, and Bernardo Bellotto. Topics include the camera obscura, an optical tool used by painters during the 1700s, and a comparison between the paintings and the actual Venetian buildings located on the Grand Canal. A study concerning the movement of algae levels since Canaletto's period and global warming are discussed. Also examined is the painting "Die Madonna der Familie Cuccina," by painter Paolo Caliari, also known as Véronèse.

Copyright of Wiener Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The discontinuous gas exchange (DGE) pattern of respiration shown by many arthropods includes periods of spiracle closure (C-phase) and is largely thought to serve as a physiological adaptation to restrict water loss in terrestrial environments. One major challenge to this hypothesis is to explain the presence of DGE in insects in moist environments. Here, we show a novel ecological correlate of the C-phase, namely, diving behaviour in mesic Paracinema tricolor grasshoppers. Notably, maximal dive duration is positively correlated with C-phase length, even after accounting for mass scaling and absolute metabolic rate. Here, we propose that an additional advantage of DGE may be conferred by allowing the tracheal system to act as a sealed underwater oxygen reservoir. Spiracle closure may facilitate underwater submersion, which, in turn, may contribute to predator avoidance, the survival of accidental immersion or periodic flooding and the exploitation of underwater resources. [ABSTRACT FROM AUTHOR]

This study examines underwater soft tissue decomposition of dismembered pig limbs deposited in polyethylene plastic bags. The research evaluates the level of influence that disposal method has on underwater decomposition processes and details observations specific to this scenario. To our knowledge, no other study has yet investigated decomposing, dismembered, and enclosed remains in water environments. The total sample size consisted of 120 dismembered pig limbs, divided into a subsample of 30 pig limbs per recovery period (34 and 71 days) for each treatment. The two treatments simulated non-enclosed and plastic enclosed disposal methods in a water context. The remains were completely submerged in Lake Ontario for 34 and 71 days. In both recovery periods, the non-enclosed samples lost soft tissue to a significantly greater extent than their plastic enclosed counterparts. Disposal of remains in plastic bags therefore results in preservation, most likely caused by bacterial inhibition and reduced oxygen levels. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPR) can have positive effects on vigour and productivity, especially under stress conditions. In asparagus (Asparagus officinalis L.) field culture, seeds are planted in high-density nurseries, and 1-year-old crowns are transplanted to production fields. Performance can be negatively affected by water stress, transplant shock, and disease pressure on wounded roots. PGPR inoculation has the potential to alleviate some of the stresses incurred in the production system. In this study, the effects of PGPR (Pseudomonas spp.) treatment were determined on 3-week-old greenhouse-grown seedlings and germinating seeds of 2 asparagus cultivars. The pots were irrigated to a predetermined level that resulted in optimum growth or the plants were subjected to drought or flooding stress for 8 weeks. The cultivars responded differently to PGPR: single inoculations of seedlings enhanced growth of ‘Guelph Millennium’ under optimum conditions and ‘Jersey Giant’ seedlings under drought stress. Seed inoculations with PGPR resulted in a positive response only for ‘Guelph Millennium’, for which both single or multiple inoculations enhanced plant growth under drought stress. [ABSTRACT FROM AUTHOR]

Abstract: Lagrangians related to submersions and foliations, which are analogous to Riemannian submersions and Riemannian foliations respectively are studied in the paper. One prove that a bundle-like Lagrangian, a transverse hyperregular Lagrangian, a hyperregular Lagrangian foliated cocycle or a geodesic orthogonal property are equivalent data for a foliation. A conjecture of E. Ghys is proved in a more general setting than that of Finslerian foliations: a foliation that has a transverse positively definite Lagrangian is a Riemannian foliation. One extend also a result of Miernowski and Mozgawa on Finslerian foliations, proving that the natural lift to the normal bundle of a Lagrangian foliation that has a transverse positively definite Lagrangian is a Riemannian foliation. [Copyright &y& Elsevier]

Water covers over 75% of the earth, has a wide variety of depths and temperatures, and holds a great deal of the earth's resources. The challenges of the underwater environment are underappreciated and more short term compared with those of space travel. Immersion in water alters the cardio-endocrine-renal axis as there is an immediate translocation of blood to the heart and a slower autotransfusion of fluid from the cells to the vascular compartment. Both of these changes result in an increase in stroke volume and cardiac output. The stretch of the atrium and transient increase in blood pressure cause both endocrine and autonomic changes, which in the short term return plasma volume to control levels and decrease total peripheral resistance and thus regulate blood pressure. The reduced sympathetic nerve activity has effects on arteriolar resistance, resulting in hyperperfusion of some tissues, which for specific tissues is time dependent. The increased central blood volume results in increased pulmonary artery pressure and a decline in vital capacity. The effect of increased hydrostatic pressure due to the depth of submersion does not affect stroke volume; however, a bradycardia results in decreased cardiac output, which is further reduced during breath holding. Hydrostatic compression, however, leads to elastic loading of the chest wall and negative pressure breathing. The depth-dependent increased work of breathing leads to augmented respiratory muscle blood flow. The blood flow is increased to all lung zones with some improvement in the ventilation-perfusion relationship. The cardiac-renal responses are time dependent; however, the increased stroke volume and cardiac output are, during head-out immersion, sustained for at least hours. Changes in water temperature do not affect resting cardiac output; however, maximal cardiac output is reduced, as is peripheral blood flow, which results in reduced maximal exercise performance. In the cold, maximal cardiac output is reduced and skin and muscle are vasoconstricted, resulting in a further reduction in exercise capacity. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new submersion, namely, screen lightlike submersion between a lightlike manifold and a semi-Riemannian manifold. We give an example and obtain a characterization for lightlike manifold to be Reinhart under such submersion. Then, we investigate the geometry of a screen lightlike submersion when the total manifold is a Reinhart lightlike manifold. [ABSTRACT FROM AUTHOR]

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A multidisciplinary team of researchers from the humanities and social sciences, including geographers, sociologists, and economists, worked together to develop a tool for evaluating coastal zone vulnerability. The results of this collaboration are presented in this article. Clearly, the vulnerability of the coastal zone is exacerbated by the combination of increasing socioeconomic stakes and high-level natural risks that come together in this limited geographical area. Whereas natural dynamics make the shoreline intrinsically mobile, with, in most cases, a tendency to drift inland, the evolving human activity in this zone adheres to a contrary logic; it progresses toward the sea, often working to define the coastline permanently through seawalls and jetties, for example. This highly developed coastal area is today at risk, the result of telescoping natural and anthropogenic forces. Given the risk, the notion of sustainable coastal development within the framework of integrated coastal zone management (ICZM) needs to be considered. If truth be told, the socioeconomic breaking point has apparently already been reached at several sites, where the cost of defending the coastline sometimes exceeds both the value of the property threatened and the financial means of the various local authorities, particularly the coastal communities. Certain imminent dangers have forced municipal governments to take emergency measures and the national government to resort to expropriation. Evaluating the risks of erosion and submersion thus appears to be an inevitable part of any forward-looking, strategic approach to coastal zone management. The method presented in this paper permits coastline vulnerability to erosion and submersion to be analyzed and evaluated from several different angles: the exposure to risk, which concentrates on the hazards and the stakes; the management of risk, which seeks to minimize risk through public policies of prevention and restoration; the remembrance of risk, which works to learn from past hazardous events; and the perception of risk, which focuses on how the different actors and users perceive the diverse risks. From these four approaches to risk analysis come five factors- hazards, stakes, management, events, and perceptions. Each one is analyzed and evaluated on a separate grid, facilitating the development of vulnerability indicators from detailed lists of descriptors. Elaborated in collaboration with risk managers and local authorities (elected officials), these grids are designed to become a decision support tool within the ICZM framework. Undertaken as part of the French National Coastal Environment Program, this research seeks to promote coastal risk management within a more integrated coastal zone management approach. [ABSTRACT FROM AUTHOR]

Abstract: Options for wetland creation or restoration might be limited because of the presence of contaminants in the soil. The influence of hydrological management on the pore water concentrations of Cd, Cr, Cu, Fe, Mn, Ni and Zn in the upper soil layer of a contaminated overbank sedimentation zone was investigated in a greenhouse experiment. Flooding conditions led to increased Fe, Mn, Ni and Cr concentrations and decreased Cd, Cu and Zn concentrations in the pore water of the upper soil layer. Keeping the soil at field capacity resulted in a low pore water concentration of Fe, Mn and Ni while the Cd, Cu, Cr and Zn concentrations increased. Alternating hydrological conditions caused metal concentrations in the pore water to fluctuate. Formation and re-oxidation of small amounts of sulphides appeared dominant in determining the mobility of Cd, Cu, and to a lesser extent Zn, while Ni behaviour was consistent with Fe/Mn oxidation and reduction. These effects were strongly dependent on the duration of the flooded periods. The shorter the flooded periods, the better the metal concentrations could be linked to the mobility of Ca in the pore water, which is attributed to a fluctuating CO2 pressure. [Copyright &y& Elsevier]

Abstract: Site-specific hydrological conditions affect the availability of trace metals for vegetation. In a greenhouse experiment, the effect of submersion on the metal uptake by the wetland plant species Salix cinerea and Populus nigra grown on a contaminated dredged sediment-derived soil and on an uncontaminated soil was evaluated. An upland hydrological regime for the polluted sediment caused elevated Cd concentrations in leaves and cuttings for both species. Emergence and soil oxidation after initial submersion of a polluted sediment resulted in comparable foliar Cd and Zn concentrations for S. cinerea as for the constant upland treatment. The foliar Cd and Zn concentrations were clearly higher than for submerged soils after initial upland conditions. These results point at the importance of submergence–emergence sequence for plant metal availability. The addition of foliar-based organic matter or aluminosilicates to the polluted sediment-derived soil in upland conditions did not decrease Cd and Zn uptake by S. cinerea. [Copyright &y& Elsevier]

We examine the power and limitations of the weakest vertex relabelling system which allows to change a label of a vertex in function of its own label and of the label of one of its neighbours. We characterize the graphs for which two important distributed algorithmic problems are solvable in this model: naming and election. [ABSTRACT FROM AUTHOR]

Background: The influence of water immersion on neuromuscular function is of importance to a number of disciplines; however, the reliability of surface electromyography (SEMG) following water immersion is not known. This study examined the reliability of SEMG amplitude during maximal voluntary isometric contractions (MVICs) of the vastus lateralis following water immersion. Methods: Using a Biodex isokinetic dynamometer and in a randomized order, 12 healthy male subjects performed four MVICs at 60° knee flexion on both the dominant and nondominant kicking legs, and the SEMG was recorded. Each subject's dominant and nondominant kicking leg was then randomly assigned to have SEMG electrodes removed or covered during 15 min of water immersion (20°C–25°C). Following water immersion, subjects performed a further four MVICs. Results: Intraclass correlation coefficient (ICC) and the relative standard error of measurement (%SEM) of SEMG amplitude showed moderate to high trial-to-trial reliability when electrodes were covered (0.93% and 2.79%) and removed (0.95% and 2.10%, respectively). Conclusions: The results of the this study indicate that SEMG amplitude of the vastus lateralis may be accurately determined during maximal voluntary contractions following water immersion if electrodes are either removed or covered with water-resistive tape during the immersion. [ABSTRACT FROM AUTHOR]

Only one prospective, controlled study has compared the risk of accidental injury in persons with epilepsy to controls without seizures. A mildly increased risk in the epilepsy group was found, predominantly due to injuries that result directly from a seizure. With regard to injury type, this study found significantly higher rates of only head and soft tissue injury; however, most injuries were minor. Several retrospective, population-based studies have suggested increased rates of more serious injury types. Submersion injury has a high mortality; the risk of submersion in children with epilepsy is 7.5–13.9 fold higher than in the general population. The risk of fracture is elevated approximately twofold, either resulting directly from seizure-induced injury or predisposed by drug-induced reduction in bone mineral density. Burns due to seizures account for between 1.6% and 3.7% of burn unit admissions. The risk of motor vehicle accidents in drivers with epilepsy also appears increased, albeit marginally. Several factors predispose to a higher risk of injury among those with epilepsy. Seizures resulting in falls increase the risk of concussion and other injuries. Higher seizure frequency, lack of a prolonged seizure-free interval, comorbid attention deficit disorder, or cognitive handicap may also increase the risk of injury. While some restrictions are necessary to protect the safety of the person with epilepsy, undue limitations may further limit achievement of independence. Given the high morbidity and mortality of submersion injury, those with active epilepsy should bathe or swim only with supervision; however, showering is a reasonable option. Appropriate vitamin D and calcium supplementation and periodic measurement of bone mineral density in those at risk for osteopenia are recommended. [ABSTRACT FROM AUTHOR]

This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confounding effect of shivering heat production was pharmacologically eliminated. Eight healthy male subjects were studied in 17°C water under four conditions: the body was either insulated or uninsulated, with the head either above the water or completely submersed in each body-insulation subcondition. Shivering was abolished with buspirone (30 mg) and meperidine (2.5 mg/kg), and subjects breathed compressed air throughout all trials. Over the first 30 rain of immersion, exposure of the head increased core cooling both in the body-insulated conditions (head out: 0.47 ± 0.2°C, head in: 0.77 ± 0.2°C; P < 0.05) and the body-exposed conditions (head out: 0.84 ± 0.2°C and head in: 1.17 ± 0.5°C; P < 0.02). Submersion of the head (7% of the body surface area) in the body-exposed conditions increased total heat loss by only 10%. In both body-exposed and body-insulated conditions, head submersion increased core cooling rate much more (average of 42%) than it increased total heat loss. This may be explained by a redistribution of blood flow in response to stimulation of thermosensitive and/or trigeminal receptors in the scalp, neck and face, where a given amount of heat loss would have a greater cooling effect on a smaller perfused body mass. In 17°C water, the head does not contribute relatively more than the rest of the body to surface heat loss; however, a cold-induced reduction of perfused body mass may allow this small increase in heat loss to cause a relatively larger cooling of the body core. [ABSTRACT FROM AUTHOR]

Abstract: A fast reusable water sensor for long-distance real-time submersion monitoring was fabricated using a macrobending-sensitive fiber (MSF). The proposed water sensor consists of floating matter, periodic macrobending deformers, and a MSF. In this structure, the floating matter moves up and down according to the buoyant force of water, thereby controlling the bending loss of the MSF and allowing the proposed sensor to detect submersion. A basic bending experiment was conducted using a MSF and macrobending deformer, and the results used to fabricate an efficient water sensor. In contrast to existing sensors where the optical loss increases in the case of submersion, the optical loss of the fabricated sensor decreases due to the buoyant force when the selected area is submerged. As such, the fabricated sensor is able to transmit submersion information further than sensors that detect submersion by increasing the optical loss, and it is unaffected by environmental factors, such as humidity and pollutants in the water. The proposed sensor detects submersion by monitoring a 16dB optical power change of 1550nm, and the change in the optical power of the fabricated sensor is only affected by the buoyant force. In addition, the proposed water sensor quickly returns to its initial state when the water disappears, and the insertion loss when it is connected to a single-mode fiber (SMF) at both ends using a connector is only −1.2dB at 1550nm. [Copyright &y& Elsevier]

Abstract: Several authors suggest that a hydrological regime aiming at wetland creation is a potential management option that favours reducing bioavailability for metal-contaminated sites. The hydrological conditions on a site constitute one of the many factors that may affect the availability of potentially toxic trace metals for uptake by plants. Bioavailability of Cd, Mn and Zn on a contaminated dredged sediment landfill (DSL) with variable duration of submersion was evaluated by measuring metal concentrations in the wetland plant species Salix cinerea in field conditions. Longer submersion periods in the field caused lower Cd and Zn concentrations in the leaves in the first weeks of the growing season. Foliar Cd and Zn concentrations at the end of the growing season were highest on the initially flooded plot that emerged early in the growing season. Foliar Zn concentrations were also high at a sandy-textured oxic plot with low soil metal concentrations. Zn uptake in the leaves was markedly slower than Cd uptake for trees growing on soils with prolonged waterlogging during the growing season, pointing at a different availability. Zn availability was lowest when soil was submerged, but metal transfer from stems and twigs to leaves may mask the lower availability of Cd in submerged soils. Especially for Cd, a transfer effect from one growing season to the next season was observed: oxic conditions at the end of the previous growing season seem to determine at least partly the foliar concentrations for S. cinerea through this metal transfer mechanism. Duration of the submersion period is a key factor for bioavailability inasmuch as initially submerged soils emerging only in the second half of the growing season resulted in elevated Cd and Zn foliar concentrations at that time. [Copyright &y& Elsevier]

Tooth ankylosis is a condition, which may lead to an occlusal abnormality. The etiology is unknown although different and often contradicting opinions have been presented. It prevails on primary teeth, characterized by progressive infraocclusion. Ankylosis on permanent teeth is less frequent and is associated with trauma and impaction. Management of the affected tooth ranges from simple observation to extraction. A protocol assisting in the proper diagnosis and treatment is presented. [ABSTRACT FROM AUTHOR]

Abstract Water immersion is a frequent cause of accidental death and hospital admission. This article outlines the pathogenesis and principles of treatment. Drowning is defined as death by asphyxia due to submersion in a liquid medium. Near-drowning is defined as immediate survival after asphyxia due to submersion. [ABSTRACT FROM AUTHOR]

Aims To understand better how often BAC-negative victims suffer fatal and non-fatal alcohol-involved injuries. Design We analyzed 1988-1993 data from Oklahoma surveillance systems that track all people killed or hospitalized due to burns, submersions and spinal cord injuries (SCIs) and investigate alcohol use by victims and any others who contributed to their injuries. Measurements Percentage of victims BAC-positive and percentage of victims BAC-negative in alcohol-involved incidents. Findings Of 5107 cases studied, alcohol involvement was known for 4773 (93%), 1882 fire burns (93%), 1560 scald and other burns (97%), 698 submersions (92%) and 967 spinal cord injuries (89%). By type of injuries, BAC-negative victims were 4%, 13%, 6% and 8% of alcohol-involved cases, respectively. Conclusion A sizeable number of BAC-negative victims suffer alcohol-involved injuries. Although alcohol is not the cause of some of these injuries, alcohol policy changes probably could avert others. [ABSTRACT FROM AUTHOR]

Plants growing on the beach are exposed to substrate mobility, freshwater inundation, and immersion in seawater, which greatly affect germination and species spatial distribution. In greenhouse experiments, we tested whether the most abundant species on the beach at La Mancha (on the Gulf of Mexico) were tolerant to burial and flooding. We buried seeds of Canavalia maritima, Ipomoea pes-caprae, Chamaecrista chamaecristoides, Palafoxia lindenii, and Ambrosia artemisiifolia at different depths. We used fresh- and seawater flooding with two frequencies: permanent and intermittent. The hard-coated seeds of Canavalia, Ipomoea, and Chamaecrista were left scarified and not scarified to test if dormancy was broken by the flooding regimes. Germination decreased as burial depth increased. We calculated a tolerance index for the burial responses, which indicated that Chamaecrista was the most tolerant species, followed by Canavalia and Palafoxia. Flooding inhibited germination, but more so permanent seawater flooding; it was especially lethal for species closest to the ocean such as Canavalia and Ipomoea. After transfer to freshwater, seeds of Chamaecrista, Palafoxia, and Ambrosia germinated. There was no evidence that hard-coat dormancy was broken by flooding. Tolerance to burial seems to be related to the spatial distribution of species but not to germination responses to flooding.Key words: germination, sand burial, freshwater, seawater, flooding, Gulf of Mexico.Les plantes poussant sur la grève sont exposées à la mobilité du substrat, à l'inondation par l'eau douce et l'immersion dans l'eau salée, ce qui affecte grandement la germination et la distribution spatiale des espèces. Au cours d'expériences menées en serres, les auteurs ont vérifié si les espèces les plus abondantes sur la grève à La Mancha (sur le golfe du Mexique) sont tolérantes à l'enfouissement et à la submersion. Ils ont enterré des graines de Canavalia maritima, d'Ipomoea pes-caprae, de Chameacrista chameacristoides, de Palaxifolia lindenii et d'Ambrosia artemisifolia à différentes profondeurs. Ils les ont submergées selon deux fréquences avec de l'eau douce et de l'eau salée : en permanence et en intermittence. Les graines à téguments durs des Canavalia, Ipomoea, et Chmaecrista ont été utilisées avec et sans scarification, pour vérifier si la dormance est brisée par les régimes de submersion. La germination diminue avec la profondeur du semis. Les auteurs ont établi un index de tolérance pour la réaction à l'enfouissement, qui indique que le Chamaecrista est l'espèce la plus tolérante, suivi du Canavalia et du Palaxifolia. La submersion inhibe la germination, ce qui est plus prononcé avec l'eau de mer; ce traitement est particulièrement létal pour les espèces venant près de la mer, soit le Canavalia et l'Ipomoea. Les graines des Chamaecrista, Palaxifolia et Ambrosia peuvent germer, après passage à l'eau douce. Il n'y a pas de preuve que la dormance des graines à téguments durs soit brisée par la submersion. La tolérance à l'enfouissement semble reliée à la distribution spatiale de l'espèce, mais non la germination en réaction à l'enfouissement.Mots clés : germination, enfouissement dans le sable, eau douce, eau de mer, submersion, golfe du Mexique.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Plants in central Amazonian floodplains are subjected to waterlogging or complete submersion for 50–270 days every year. Most trees have growth reductions, photosynthetic activity can be reduced for some weeks to months, and leaf fall increases during the high-water period, but leaf flush, flowering and fruiting also occur in waterlogged plants. Whether flooding can trigger the changes in phenology, growth and metabolism of the plants has not yet been established. The aim of this study was to analyse the extent to which waterlogging was directly responsible for morphological, phenological and physiological changes in floodplain seedlings. In two flooding experiments performed at different times of the year, the effects of waterlogging, submersion and drought were tested in seedlings of six species with different growth strategies. One experiment was performed in the period of highest precipitation and rising river levels, and a second experiment in the period of highest river levels and the onset of the period of lowest precipitation. All results were comparable in the two experiments, and the morphological, phenological and physiological responses were linked to the treatments. Height growth and new leaf production were not severely affected in the waterlogged seedlings. All waterlogged plants produced adventitious roots, lenticels and stem hypertrophy. Submersion and drought caused a state of rest, but soon after the water had receded, leaves resprouted. Five to 12 weeks after the end of submersion, the seedlings reached the height of the control plants, showing a high ability to compensate the period of rest induced by submergence. Only the three deciduous species subjected to waterlogging showed a different phenological behaviour in the two experiments, perhaps related to genetically fixed phenological rhythms which are synchronous to those of adult trees in the field. [ABSTRACT FROM AUTHOR]

Background-Heart rate variability (HRV) describes the cyclic variations in heart rate and offers a non-invasive tool for investigating the modulatory effects of neural mechanisms elicited by the autonomic nervous system on intrinsic heart rate. Objective-To introduce the HRV concept to healthy volunteers under control conditions and during scuba diving. In contrast with more established manoeuvres, diving probably activates both the sympathetic and parasympathetic nervous system through various stimuli-for example, through cardiac stretch receptors, respiration pattern, psychological stress, and diving reflex. A further aim of the study was to introduce a measure for determining a candidate's ability to scuba dive by providing (a) standard values for HRV measures (three from the time domain and three from the frequency domain) and (b) physiological responses to a strenuous manoeuvre such as scuba diving. Methods-Twenty five trained scuba divers were investigated while diving under pool conditions (27°C) after the effects of head out immersion and submersion on HRV had been studied. Results and conclusions-(a) Immersion under pool conditions is a powerful stimulus for both the sympathetic and parasympathetic nervous system. (b) As neither the heart rate nor the HRV changed on going from immersion to submersion, the parasympathetic activation was probably due to haemodynamic alterations. (c) All HRV measures showed an increase in the parasympathetic activity. (d) If a physiological HRV is a mechanism for providing adaptability and flexibility, diving should not provoke circulatory problems in healthy subjects. (e) Either a lower than normal HRV under control conditions or a reduction in HRV induced by diving would be unphysiological, and a scuba diving candidate showing such characteristics should be further investigated. [ABSTRACT FROM AUTHOR]

Storm Xynthia, which hit the French Atlantic coast on 28 February 2010, flooded vast territories despite coastal defences. This disaster highlighted the need to further study the behaviour of the coastal flood protection systems at an adapted geographical scale by considering the kinematics of the events. This objective has been achieved through a combination of conceptual input on the definition of protection systems, significant breakthroughs in the knowledge of the mechanisms governing the flooding, and via the improvement of strategies and methods dedicated to flood analysis and representation. The developed methodology was successfully tested on four sites submerged during Xynthia (Loix, Les Boucholeurs, and Boyardville, located in Charente-Maritime, and Batz-sur-Mer, located in Loire-Atlantique). This work is intended to guide the diagnosis of sites prone to marine flooding from the first investigations until the delivery of study reports. Beyond the usual focus on hydraulic structures, it provides guidelines to better analyse the interactions with the natural environment (sea, soil, dune, wetlands, etc.) and with the built environment (roads and urban networks, ponds used for fish farming, buildings, etc.). This systemic approach, which is applied to a territory considered as a complex adaptive system, is fundamental to understanding the reaction of a territory during a marine submersion event and subsequently developing adaptation or transformation strategies. [ABSTRACT FROM AUTHOR]

By writing the O'Neill tensors as derivatives of the natural projection one does not need the usual case distinctions any more and gets a much shorter list of basic equations. A short, induction free proof of the Frobenius theorem is a by-product. [ABSTRACT FROM AUTHOR]