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PubMed2005

Effects of snowfalls on motor vehicle collisions, injuries, and fatalities.

OBJECTIVES: We estimated the effects of snowfalls on US traffic crash rates between 1975 and 2000. METHODS: We linked all recorded fatal crashes (1.4 million) for the 48 contiguous states from 1975 through 2000 to daily state weather data. For a subsample including 17 states during the 1990s, we also linked all recorded property-damage-only crashes (22.9 million) and nonfatal-injury crashes (13.5 million) to daily weather data. Employing negative binomial regressions, we investigated the effects of snowfall on crash counts. Fixed effects and other controls were included to address potential confounders. RESULTS: Snow days had fewer fatal crashes than dry days (incidence rate ratio [IRR] = 0.93; 95% confidence interval [CI] = 0.90, 0.97), but more nonfatal-injury crashes (IRR = 1.23; 95% CI = 1.18, 1.29) and property-damage-only crashes (IRR=1.45; 95% CI=1.38, 1.52). The first snowy day of the year was substantially more dangerous than other snow days in terms of fatalities (IRR = 1.14; 95% CI=1.08, 1.21), particularly for elderly drivers (IRR=1.34; 95% CI=1.23, 1.50). CONCLUSIONS: The toll of snow-related crashes is substantial. Our results may help estimate the potential benefits of safety innovations currently proposed by meteorology and traffic safety experts.

Accidents, Traffic↗
PubMed2001

Reuse of heat energy in wastewater: implementation examples in Japan.

Sewage and treated water can be a heat source in urban area due to large heat capacity, thus recovery and reuse of its energy is one of the most desirable plans for the sewerage system. In this paper, characteristics of heat energy in wastewater, reuse plans, and some experiences in Japan are presented. Full-scale reuse projects for heating and cooling in the Tokyo Metropolitan Districts and project for melting snow in Sapporo City are discussed. The key factors found in experience of Tokyo were setting the heat pumps near the demand points and the technical developments of equipment to prevent system from clogging, corrosion, and decrease in the heat transfer efficiency. It was also found through the project for melting snow in Sapporo that the key factor in public acceptance was the multi-purpose use of the sewerage system both for melting snow in winter and retaining rain water in summer.

Air Conditioning↗
PubMed2003

Review of operation of urban drainage systems in cold weather: water quality considerations.

Cold climate imposes special requirements on urban drainage systems, arising from extended storage of precipitation and pollutants in the catchment snowpack, processes occurring in the snowpack, and changes in catchment surface and transport network by snow and ice. Consequently, the resulting catchment response and runoff quantity differ from those experienced in snow- and ice-free seasons. Sources of pollutants entering urban snowpacks include airborne fallout, pavement and roadside deposits, and applications of de-icing and anti-skid agents. In the snowpack, snow, water and chemicals are subject to various processes, which affect their movement through the pack and eventual release during the melting process. Soluble constituents are flushed from the snowpack early during the melt; hydrophobic substances generally stay in the pack until the very end of melt and coarse solids with adsorbed pollutants stay on the ground after the melt is finished. The impacts of snowmelt on receiving waters have been measured mostly by the snowmelt chemical composition and inferences about its environmental significance. Recently, snowmelt has been tested by standard bioassays and often found toxic. Toxicity was attributed mostly to chloride and trace metals, and contributed to reduced diversity of benthic and plant communities. Thus, snowmelt and winter runoff discharged from urban drainage threaten aquatic ecosystems in many locations and require further studies with respect to advancing their understanding and development of best management practices.

Cities↗
PubMed2003

Seasonal variations in road runoff quality in Luleå, Sweden.

In regions with cold climate the urban drainage and highway runoff processes become much more complex, compared to temperate regions. Therefore, climatic conditions should be taken into account in planning and design of BMPs and snow handling strategies. In order to increase the knowledge of road runoff quality during melt and rain periods, respectively, measurements were carried out at a field site during a two-month period. The field site was situated at Södra Hamnleden, a road with 7,400 vehicles/day, in the central part of Luleå. Runoff samples were analysed for suspended solids and heavy metals (Pb, Cu, Cd, Ni and Zn). The results showed that the concentrations of suspended solids, lead, copper and cadmium were higher for the melt period, compared to rain generated runoff on the catchment without snow, and the highest concentrations were found during the rain-on-snow events. The results indicate a flow dependent increase in the concentration of suspended solids during the melt period. A comparison of the total mass of suspended solids over a one-month period showed that the melt period produced about 3 times more suspended solids. Metal elements during melt period were more particulate bound as compared to the rain period characterised by a higher percentage of the dissolved fraction.

Climate↗
PubMed2004

[Snow/wind damage in natural secondary forests in Liaodong mountainous regions of Liaoning Province].

In early spring of 2003, the secondary forests at the Qingyuan Experimental Forests (QEF) of the Institute of Applied Ecology, Chinese Academy of Sciences suffered from the damage caused by snow and wind (snow/wind damage). This damage occurred at 800 m above sea level was the most serious one since 1949. In order to make clear its occurrence and process and to analyze its possible influences on the secondary forest system, comprehensive investigations were conducted soon after the snow/wind damage. The results showed that the occurrence of this damage was due to the special site conditions (higher sea level and steeper slopes) and air temperature, which suited the wet snow formation and the snow accumulation on trees after a large scale of precipitation. The more seriously damaged areas were those with the stands of Acer mono, Juglans mandshurica, Populus spp. and so on. The ratio of damaged trees was negatively correlated with stand density, soil depth and size class of diameter, and positively correlated with tree height. Based on these results, the likely influences of snow/wind damage, i. e., the happening of diseases and insect pests, the vegetation changing under forests, and the factors of habitat and dominant species in natural secondary forests were also discussed. It is significant that to do observation and basic research on damaged forests will provide reasonable strategies for management of natural secondary forests.

China↗
PubMed1993

[Avalanche accidents].

Most avalanche victims die from asphyxia (68%) followed by trauma (13%). Hypothermia is a less common cause of death. Asphyxia may be caused by obstructed airways owing to aspiration of snow, an immobile thorax due to compression by the surrounding snow or lack of diffusion of oxygen through the mass of snow. Clearing airways and quick mobilization of the thorax are of utmost importance in the initial treatment. Cardiopulmonary resuscitation may be required. Unconscious victims without vital signs should be treated in the same way as victims with severe hypothermia.

Asphyxia↗
PubMed1996

[Differential diagnosis of circulatory failure in hypothermic avalanche victims: retrospective analysis of 32 avalanche accidents].

In avalanche accidents the cause of cardio-respiratory arrest (asphyxia, hypothermia, trauma) is difficult to determine in the field but may be important (high number of victims, limited number of rewarming places). 32 avalanche accidents (16 survivors/16 deaths) were therefore reviewed retrospectively. In 19 patients with cardiorespiratory arrest, asphyxia was frequent (17 patients, 89%) hypothermia was rare (two patients, 11%). The cooling rate between the accident and the arrival at the hospital was 3.0 degrees C/h. (range 0.75-5.8). The core temperature at arrival in the hospital was dependent on the time spent buried under the snow (survivors) and total time (nonsurvivors). The maximal cooling rate under the snow was estimated at 8 degrees C/h. Cardiorespiratory arrest in hypothermic patients without asphyxia seems only to be possible after being buried for at least 1 h. under the snow. Serum potassium was elevated in most cases of asphyxia.

Accidents↗
PubMed2000

Thermoregulation in Antarctic fulmarine petrels.

We measured resting metabolic rates at air temperatures between ca. -5 and 30 degrees C in snow petrels (Pagodroma nivea), cape petrels (Daption capense), Antarctic petrels (Thalassoica antarctica), and Antarctic fulmars (Fulmarus glacialoides). We measured seven age classes for each species: adults, and nestlings that were 3, 8, 15, 28, 35, and 42 days old. Basal metabolic rate (BMR) and thermal conductance (C) of adults averaged, respectively, 140% and 100% of values predicted allometrically for nonpasserine birds. Minimum metabolic rates of unfasted nestlings aged 15-42 days averaged, respectively, 97% and 98% of predicted adult BMR in Antarctic petrels and snow petrels, versus 119% and 126% of predicted in Antarctic fulmars and cape petrels. Nestlings of the southerly breeding snow petrel and Antarctic petrel were relatively well insulated compared with nestlings of other high-latitude seabirds. Adult lower critical temperature (T1c) was inversely related to body mass and averaged 9 degrees C lower than predicted allometrically. As nestlings grew, their T1c decreased with increasing body mass from ca. 14 to 22 degrees C (depending upon species) at 3 days of age, to -4 to 8 degrees C when nestlings attained peak mass. Nestling T1c subsequently increased as body mass decreased during pre-fledging weight recession. Nestling T1c was close to mean air temperature from the end of brooding until fledging in the three surface nesting species.

Aging↗
PubMed2005

Predation regulation of sedimentary faunal structure: potential effects of a fishery-induced switch in predators in a Newfoundland sub-Arctic fjord.

The collapse of the cod fishery in Newfoundland has coincided with marked increases in abundances of snow crab, pandalid shrimp, and other crustaceans that prey on sedimentary infauna. A 3-year sampling program in Bonne Bay, Newfoundland indicates differences in composition and number of these predators in the two main arms of the fjord that coincide with strong differences in benthic community structure. To test whether predation pressure contributes to the observed patterns in sedimentary fauna, exclusion field experiments with full and partial cages were deployed in both arms at 30-m depth and sampled along with ambient sediments at 0-, 4-, and 8-week periods. Predation significantly influenced species composition, abundance and, in some cases, diversity. The most striking changes included increases in the polychaetes Phöloe tecta and Ophelina cylindricaudata in exclusions relative to controls, and concurrent declines in the polychaete Paradoneis lyra and the cumacean Lamphros fuscata. In laboratory experiments, fresh non-disturbed sediment cores from each experimental area were either protected or exposed to snow crab, the most abundant predator in the bay. A snow crab inclusion experiment was also carried out in the field, using cages similar to those used for exclusions. Despite differences in sedimentary faunas in the two arms, both types of experiments detected a predator effect that was very similar to that documented in exclusion experiments. Thus, despite differences in the scales associated with each type of manipulation, our results suggest that crab predation is a significant structuring force in Newfoundland sedimentary communities. Given the historical changes that have occurred in predator composition as a result of cod over-fishing, we hypothesize that broad-scale community changes may be taking place in North Atlantic benthic ecosystems.

Analysis of Variance↗
PubMed1992

Orographic enhancement of snowfall.

Field studies have been conducted at a hill site in Scotland to measure the variation with altitude of wet deposition by snowfall. The results showed that, due to wind drift effects, snowflakes were captured very inefficiently by snow collectors. It was therefore not possible to measure an increase in precipitation with altitude. The average concentrations of principal ions dissolved in the snow water were calculated over a two-month period. The results showed that the concentrations increased by factors of between 1.4 and 1.9 with an altitude rise of 400 m. A model of the orographic enhancement of snowfall by the seeder-feeder effect showed that the orographic enhancements of precipitation and pollutant deposition were significantly greater for snowfall than for rainfall. The wind drift of snow crystals and the evaporation of precipitation in dry valley air were important in determining the patterns of deposition.

Journal Article↗
PubMed1995

The composition of rime ice as an indicator of the quality of winter deposition.

Rime ice deposition and snow chemistry has been determined over a 4-year period on the summit of Cairngorm Mountain, NE Scotland. The direction of ice deposition reflected the dominant air mass movement over the summit. Sea salt concentrations in the rime ice were approximately 2.5 times greater than in snow deposited over the same period. Excess sulphate concentrations were double, and those of nitrate nearly four times higher. The direction of deposition influenced concentrations of excess sulphate and nitrogen species (nitrate and ammonium) in rime ice. The same directional effect was found in the snow chemistry indicating increased entrapment of pollutants, or a more polluted air mass, when it prevailed from a Southerly or Easterly direction. The potential surface reactions involving gaseous species of S and N may increase the ionic loading to the rime and reflect natural ionic enrichment of the rimed snowpack surface. Because of such phenomena, rime ice is proposed as a further indicator of winter air quality revealing important information on ionic interactions and total deposition flux measurement, especially at high altitudes.

Journal Article↗
PubMed1996

Current and historical relationships between the tissue nitrogen content of a snowbed bryophyte and nitrogenous air pollution.

Snowbed vegetation is under threat from atmospheric pollution. Most of the late lying snowbeds in Britain are in the central highlands of Scotland, coinciding with an area of very high deposition of nitrogenous air pollutants. Snow is a very efficient scavenger of atmospheric pollution and, due to the dynamics of snowmelt, much of the pollution load of a snow pack is released at very high concentrations in episodes known as 'acid flushes'. This study demonstrates the existence of a positive relationship between duration of snow-lie and tissue nitrogen content of Kiaeria starkei, a bryophyte characteristic of late snowbeds. An increase in the tissue nitrogen content of this bryophyte over this century is also shown, reflecting increasing air pollution. Maximum tissue nitrogen concentration in K. starkei is up to 50% greater than that recorded in other upland bryophyte species, demonstrating the exceptional threat of pollution to snowbed bryophytes. This has implications for the critical loads approach to pollution emission controls, as it indicates that some mountain communities are receiving higher pollution loadings than previously realised and therefore current exceedence of critical loads is probably greater than recognised at present.

Journal Article↗
PubMed1985

Effect of season and weather on pediatric emergency department use.

It is commonly believed that emergency department (ED) use is affected by extreme weather. To test this hypothesis, data concerning use of a pediatric ED during three seasonally diverse months was analyzed in the light of Weather Bureau information concerning daily conditions during the study months. Seven measures of extreme weather were defined: 1) extreme cold (daily high temperature less than or equal to 25 degrees F); 2) extreme heat (daily high temperature greater than or equal to 88 degrees F); 3) unusual cold (winter) with departure from normal of mean temperature less than -10 degrees F; 4) unusual heat (summer) with departure from normal of mean temperature greater than 10 degrees F; 5) precipitation greater than or equal to 0.25 inches (in water-equivalent inches); 6) stormy (thunderstorm, hail, ice, or blowing snow); 7) snow-covered (greater than or equal to 6 inches of snow on the ground). Seasonal use patterns were examined and the proportion of days with each weather factor was compared with the proportion of visits on days with the factor. The data indicate 1) season has a major affect on ED use because it affects prevalence of disease and injury; 2) extremely cold and stormy conditions significant reductions in ED use of approximately 5-20%; 3) 80-95% of expected visits are made on days with very bad weather. The data indicate that weather is a minor factor in determining ED use.

Child↗
PubMed2005

Assessment of anti-slip devices from healthy individuals in different ages walking on slippery surfaces.

The interest for effective preventive strategies for slips and falls is growing. Much remains to be done, however, to prevent slips and falls in the traffic environment. Using an appropriate anti-slip device may reduce the risk of slips and falls on different surfaces outdoors during winter. The aim of this study was to evaluate the best anti-slip devices of different designs in the Swedish market on a larger group of healthy individuals in different ages on five different slippery surfaces as a way to develop a standard method to test anti-slip devices. Three different designs of anti-slip devices: heel device, foot-blade device and whole-foot device were evaluated on ice surfaces uncovered or covered with gravel, sand, salt or snow. The evaluations were done according to subject's perceived walking safety and balance, videorecordings of walking postures and movements, time to take on and off each anti-slip device, advantages/disadvantages with each anti-slip device and a list of priorities for own use according to three criteria: safety, balance and appearance. The heel device was perceived to be the most safe on all five surfaces, followed by the toe device and the whole-foot device. The heel device was also perceived to be the one with the best walking balance on uncovered ice and on snow covered ice. There were some significant differences due to gender and age. Most subjects walked with a normal muscle function in the hip and knee when walking with or without an anti-slip device on all surfaces. The heel device was perceived as the most rapid one to take on and the toe device as the most rapid one to take off. All three devices were perceived as having a good foothold. The heel device was perceived to fit the shoe and to be stable at heel-strike. The toe device was easily portable and stable on uncovered ice. The whole-foot device was comfortable to walk with and safe on snow covered ice. The heel device had the highest priority according to walking safety, walking balance and choice for own use.

Accidental Falls↗
PubMed2006

Propagation of program control: a tool for distributed disease surveillance.

PURPOSE: The purpose of the study was (1) to identify the requirements for syndromic, disease surveillance and epidemiology systems arising from events such as the SARS outbreak in March 2003, and the deliberate spread of Bacillus anthracis, or anthrax, in the US in 2001; and (2) to use these specifications as input to the construction of a system intended to meet these requirements. An important goal was to provide information about the diffusion of a communicable disease without being dependent on centralised storage of information about individual patients or revealing patient-identifiable information. METHODS: The method applied is rooted in the engineering paradigm involving phases of analysis, system specification, design, implementation, and testing. The requirements were established from earlier projects' conclusions and analysis of disease outbreaks. The requirements were validated by a literature study of syndromic and disease surveillance systems. The system was tested on simulated EHR databases generated from microbiology laboratory data. RESULTS: A requirements list that a syndromic and disease surveillance system should meet, and an open source system, "The Snow Agent system", has been developed. The Snow Agent system is a distributed system for monitoring the status of a population's health by distributing processes to, and extracting epidemiological data directly from, the electronic health records (EHR) system in a geographic area. CONCLUSIONS: Syndromic and disease surveillance tools should be able to operate at all levels in the health systems and across national borders. Such systems should avoid transferring patient identifiable data, support two-way communications and be able to define and incorporate new and unknown diseases and syndrome definitions that should be reported by the system. The initial tests of the Snow Agent system shows that it will easily scale to national level in Norway.

Communicable Diseases↗
PubMed2001

Test of swedish anti-skid devices on five different slippery surfaces.

The interest for effective preventive strategies for slips and falls is growing. Much remains to be done, however, to prevent slips and falls in the traffic environment. Some pedestrians are injured because of slippery pavements and roadways. Using an appropriate anti-skid device may reduce the risk of slips and falls on different surfaces outdoors during winter. The aim of this study was to evaluate new anti-skid devices on the Swedish market representing three different designs of anti-skid devices; heel device, fore-foot device and whole-foot device on different slippery surfaces, gravel, sand, salt, snow and ice. The evaluations were done according to subject's perceived walking safety and balance, videorecordings of walking postures and movements, time to take on and off each anti-skid device, advantages/disadvantages with each anti-skid device and a list of priority for own use according to three criteria; safety, balance and appearance. Practical tests were carried out on different slippery surfaces, gravel, sand, salt, snow and ice. The subject's were randomly selected from the registered population over 55 years in a city in northern Sweden. The results showed that eight or more of the ten subjects perceived all four anti-skid devices as fairly good or good regarding walking safety and balance when walking on gravel, sand, and salt. Anti-skid device 3, a whole-foot device was perceived as having none or bad walking safety and balance on snow by seven subjects and anti-skid device 4, a heel device, as having none or bad walking balance on ice by all ten subjects. Eight subjects walked with a normal muscle function in the hip and knee with all anti-skid devices on all surfaces. Small deviations in walking posture and movements were noted in one to two subjects when walking on different surfaces, but no systematic difference between the devices. Anti-skid device 1 'Rewa', a fixed heel device, was perceived as the most rapid one to take on. All four devices were perceived as easy to use and as giving good foothold. Anti-skid device 1 'Rewa' and 4 'Thulin-spike', both heel devices, had the highest priority according to walking safety. 'Rewa' also had the highest priority according to walking balance as well as own use. When combining the criterias 'Rewa' had the highest priority according to walking safety and balance, priority for own use, time to take on and easiness to use.

Accidental Falls↗
PubMedDate not supplied

[Flight into the imaginary world and dependence: personality trait or opportunist defence mechanism in the transsexual].

While analysing the psychological functioning of sex reassignment candidates, it appeared that they frequently use the mechanism which consist in taking refuge in passivity and fantasies so that they can avoid displeasing situations, responsibilities and decisions making. This unconscious process, identified by Exner in the Rorschach as the Snow-White Syndrome seems to take place in a specific way regarding the real situation faced by the sex reassignment candidates: the achievement of their aim (the sex reassignment) actually depends on the medical crew (doctors, psychologists, surgeons). We wondered if this fact consisted in a stylistic component, that is to say a stable feature of transsexuals' personality or in an opportunist defence. The dependence on the third, executor and decision-maker could be seen either as the indication of this feature being a favourable condition to the construction of the transsexual Issue or a consequence the transsexual's real situation. The hypothesis of the situational use of this process is studied by comparing the frequency of the Snow-White Syndrome during the moment before giving the surgical response with its appearance frequency after the sex reassignment. The individuals' retest (7MF/7FM) after the operation brings favourable arguments to the second interpretation since the process stops being used as soon as the passive dependence position doesn't exist anymore (the Snow-White Syndrome disappears in 70% of cases). So, as the goals are reached (the medico-surgical transformation materialising the desire), the flight in fantasies and passivity is not necessary anymore and the dependence on contributors disappears. During the psychological follow-up, attention should be paid to this psychic impact of anatomical reality so that it favours an earliest access to autonomy the transsexual is able to prove. In regard of a psychological view (in opposition with a surgical view), this autonomy could be researched before the body transformation, validating the "Real Life Test" experience.

Adult↗
PubMed1997

Seasonal variability of total and easily leachable element contents in topsoils (0-5 cm) from eight catchments in the European Arctic (Finland, Norway and Russia).

Frozen topsoil samples (0-5 cm) were collected during March/April 1994 in eight Arctic catchments in northern Europe (4 in Russia, 3 in Finland, 1 in Norway) at varying distances and wind directions from the emissions of the Russian nickel ore mining, roasting and smelting industry on the Kola Peninsula. Between 14 and 25 sites were sampled in catchment basins ranging in size from 12 to 35 km(2). Sampling was repeated in spring immediately after the snow melted, in summer and in autumn to study seasonal variability and the fate of elements when the snow melts. The <2 mm fraction of air-dried topsoils was analysed for total (aqua regia extraction) and easily leachable (in 1 m ammonium acetate, buffered at pH 4.5) element concentrations using ICP-AES and GFAAS for up to 35 elements. Results for selected elements are presented here. Soil organic matter can be shown to be the controlling factor determining element contents and fate. In catchments close to the Russian nickel industry, the topsoils have low carbon and nitrogen contents. Using both extraction methods most elements reach maximum concentrations in winter; lowest concentrations are observed in midsummer. Soil organic matter and elements associated with it are thus leached out of the soils together with soluble elements when the snow melts. This process continues in summer. Elements will enrich surface waters, the lower layers of podzol profiles, or reach the groundwater. The use of the two extractions described provides a simple method to study the mobilities and pathways of elements in the topsoils during the arctic year. Using the proportions of easily leachable to total concentration, a good estimation of the status of the topsoil in the study area can be given.

Journal Article↗