Suicides and other fatalities from train-person collisions on Swedish railroads: a descriptive epidemiologic analysis as a basis for systems-oriented prevention

PROBLEM: Suicide is a dominating, although hidden, safety problem on Swedish railroads. The aim of this paper is to describe the epidemiology of fatal train-person collisions as a basis for systems-oriented prevention. METHOD: Data on collision circumstances were collected from narrative reports at the Swedish National Rail Administration. RESULTS: The events were evenly distributed by months and weekdays, however, most suicides occur during the day while unintentional events usually occur at night. Most train-person collisions happened in densely populated areas, and 75% of the suicide victims were waiting on the track before the collision. Significance test between types of injury event (suicide, accident, or unknown intent) showed small or no differences. CONCLUSION: Traditional approaches to accident prevention by systems modification seem largely applicable to combat railroad suicide as well. IMPACT ON INDUSTRY: Our findings show promising preventive potentials.     

Modelling the transport of radionuclides from land to water

This paper addresses some fundamental problems related to the structure and function of catchment areas in general and for seasonal (weekly, monthly) mass balance calculations of radionuclides (and metals, organics and nutrients) in particular. A new catchment area model has been developed and critically tested. This modelling approach is based on mechanistic principles. The catchment area is differentiated into inflow ( approximately dry land) areas and outflow (=wetland) areas. The model also accounts for time-dependent fixation of substances in the catchment related to single-pulse fallouts. The model has a general structure. It is simple to use since there are only two soil type classes and three categories for the outflow areas. In critical tests, the model was put within a framework where it is intended, i.e., within a more comprehensive lake model. Radiocesium was used as a tracer in these tests. Modelled values were compared to empirical data from 23 lakes (351 data on (137)Cs in water, as well as in sediments, small fish and on suspended particles) covering a very wide limnological domain (latitudes from 42 to 61 degrees V, altitudes from 0 to 1090 m ASL, catchment areas from 0.17 to 114,700 km(2), precipitation from 430 to 1840 mm/year, lake areas from 0.042 to 1147 km(2), mean depths from 1.1 to 90 m, pH from 5.1 to 9 units, potassium concentrations from 0.23 to 27.5 mg/l, total P concentrations from 8.3 to 100 microg/l and theoretical water retention times from 0.02 to 137 years). When modelled values were compared to empirical data, the slope was almost perfect (0.99) as well as the coefficient of determination (r2 = 0.96).     

Bird skins in museum collections: are they suitable as indicators of environmental metal load after conservation procedures?

To find out whether modern conservation treatments alter thelevel of metals in feathers, we analysed the content of 10metals in feathers before and after skins were washed withdetergent and treated with Eulan U-33 (a commonly usedpreservative at museums). Feathers of 31 birds of Goshawk Accipiter gentilis, Eagle Owl Bubo bubo, Feral PigeonColumba livia domest. and Common Eider Somateriamollissima were analysed. We found that in most cases metalswere partly washed out of the feathers, but the effects wererelated to species and type of feather. The value of bird skinsas indicators of environmental metal load is therefore affectedby this treatment. It is recommended that the conservationtechniques used at museums should be reconsidered if skins areintended for specimen banking for future reference inenvironmental monitoring schemes and research.     

Evidence of equal maternal investment in the sexes in the polygynous and sexually dimorphic grey seal (Halichoerus grypus)

In polygynous and sexually dimorphic mammals, parents may be expected to bias their investment towards sons because variation in reproductive success is usually higher among males than among females. Moreover, male reproductive success often depends on adult body size, which, in turn, may depend on the level of parental investment. We therefore predicted that in the grey seal (Halichoerus grypus), a polygynous and sexually dimorphic phocid seal, females should invest more in individual sons than in individual daughters. We found that male pups were born heavier than female pups, but that the growth rates and suckling behaviour were similar for the two sexes. The growth rates and the birth weights were not correlated for the pups of either sex. Mothers did not behave differentially towards offspring of the two sexes, except that mothers of male pups spent more time in visual contact with their pups. Male and female pups had similar activity levels and begged at similar rates. We argue that reports of equal expenditure on the two sexes can be accepted as evidence of equal investment, provided that three assumptions are fulfilled. First, parental care must be costly to the parent. Second, energy expenditure must be the most important component of parental investment. Third, there must be no negative correlation between maternal body condition and the ratio of sons to daughters produced. We argue that these assumptions are met in our study, and that our results provide evidence of equal maternal investment in the sexes in grey seals.     

First evidence of regular common cuckoo, <Emphasis Type="Italic">Cuculus canorus</Emphasis>, parasitism on eastern olivaceous warblers, <Emphasis Type="Italic">Hippolais pallida elaeica</Emphasis>

Coevolution is defined as specialized relationships between species that lead to a reciprocal evolutionary change. A particularly suitable model system for studying coevolution is the interactions between obligate avian brood parasites and their hosts. The common cuckoo (Cuculus canorus, hereafter cuckoo) is a well-known brood parasite, which utilizes a range of smaller passerines as hosts. However, warblers of the genus Hippolais have rarely been reported as being victims of cuckoos, and furthermore, few data exist on the occurrence of antiparasite defenses in these hosts. In this study, we examined possible host–parasite coevolution between cuckoos and eastern olivaceous warblers (Hippolais pallida elaeica, hereafter olivaceous warblers) in three closely situated areas in northwestern Bulgaria. The olivaceous warbler has never been reported to be a regular cuckoo host. However, the present study, carried out in 2001–2003 shows that the olivaceous warbler is regularly and heavily parasitized by the cuckoo in this area. Parasitism rate was high (26.6%, 34/128) and consistent among years, with some variation between areas. The cuckoo egg mimicry was moderately good, and olivaceous warbler rejection rate of such eggs was 50%. Cuckoo eggs laid in olivaceous warbler nests had a whitish to whitish-green ground color, and the majority appeared to be distinctly different from cuckoo eggs found in other host species in the area. The olivaceous warbler proved to be a rather good host for cuckoos as 20.6% (7/34) of cuckoo eggs laid produced fledglings, a breeding success comparable to other suitable hosts in Europe. This is the first in-depth study of brood parasitism in a warbler of the genus Hippolais, and cuckoos parasitizing olivaceous warblers probably represent a previously unknown gens.     

Assessment of Bilateral Thoracic Loading on the Near-Side Occupant Due to Occupant-to-Occupant Interaction in Vehicle Crash Tests

Objective: This study aims, by means of the WorldSID 50th percentile male, to evaluate thoracic loading and injury risk to the near-side occupant due to occupant-to-occupant interaction in combination with loading from an intruding structure.

Method: Nine vehicle crash tests were performed with a 50th percentile WorldSID male dummy in the near-side (adjacent to the intruding structure) seat and a THOR or ES2 dummy in the far-side (opposite the intruding structure) seat. The near-side seated WorldSID was equipped with 6 + 6 IR-Traccs (LH and RH) in the thorax/abdomen enabling measurement of bilateral deflection. To differentiate deflection caused by the intrusion, and the deflection caused by the neighboring occupant, time history curves were analyzed. The crash tests were performed with different modern vehicles, equipped with thorax side airbags and inflatable curtains, ranging from a compact car to a large sedan, and in different loading conditions such as car-to-car, barrier, and pole tests. Lateral delta V based on vehicle tunnel acceleration and maximum residual intrusion at occupant position were used as a measurement of crash severity to compare injury measurements.

Result: In the 9 vehicle crash tests, thoracic loading, induced by the intruding structure as well as from the far-side occupant, varied due to the size and structural performance of the car as well as the severity of the crash. Peak deflection on the thoracic outboard side occurred during the first 50 ms of the event. Between 70 to 150 ms loading induced by the neighboring occupant occurred and resulted in an inboard-side peak deflection and viscous criterion. In the tests where the target vehicle lateral delta V was below 30 km/h and intrusion less than 200 mm, deflections were low on both the outboard (20–40 mm) and inboard side (10–15 mm). At higher crash severities, delta V 35 km/h and above as well as intrusions larger than 350 mm, the inboard deflections (caused by interaction to the far-side occupant) were of the same magnitude or even higher (30–70 mm) than the outboard deflections (30–50 mm).

Conclusion: A WorldSID 50th percentile male equipped with bilateral IR-Traccs can detect loading to the thorax from a neighboring occupant making injury risk assessment feasible for this type of loading. At crash severities resulting in a delta V above 35 km/h and intrusions larger than 350 mm, both the inboard deflection and VC resulted in high risks of Abbreviated Injury Scale (AIS) 3+ injury, especially for a senior occupant.