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PubMedDate not supplied

Respiratory effects of occupational exposure to an epoxy resin system.

A standardized respiratory questionnaire and pulmonary function tests were used to examine thirty-four employees of a snow-ski manufacturing plant, including twenty-five workers who were exposed to an epoxy resin system containing the amine hardener 3-dimethylamino propylamine (3-DMAPA). Maximum expiratory flow-volume curves were obtained on Monday and Thursday, before and after each shift, and FVC, FEV1.0, MEF50%, and MEF25% were caculated. Environmental measurements of the total amine levels were found to range from 0.41 to 1.38 ppm. The group with the greatest exposure (0.55-1.38 ppm) showed significant decreases in lung function over Monday and over the week. Although all employees in this group showed decreases in pulmonary function, acute changes were greater in present cigarette smokers and in subjects who reported respiratory symptoms upon exposure to the epoxy resin system. There was no evidence of permanent loss of lung function in subjects with either the highest or longest exposure.

Adult↗
PubMedDate not supplied

Physical dosimetry and biological indicators of carcinogenic risk in a cohort of persons exposed to unhealthy ecological factors following the Chernobyl Nuclear Power Plant accident.

The April 1986 Chernobyl Nuclear Power Plant accident caused ecological changes in the Ovruch State forests in the Zhytomir oblast in the Ukraine. The highest radioactivity existed in moss, followed by the pine-forest substrate and soil. During 1984-1985, the pine needles were primarily surface contaminated, whereas during 1986-1988, they were contaminated secondarily. Radioactivity in air was highest (1.07+/-0.185 Bq/l) during dry and sunny weather and when trees were felled; the lowest levels (0.196+/-0.044 Bq/l) occurred during periods of stable snow coverage. Between 1987 and 1989 (i.e., after the Chernobyl accident), the caesium levels in forestry employees exceeded by 13.9-fold the average levels found in the Ukrainian Polessje population. Ovruch forest guards and woodcutters had the highest effective equivalent doses of radiation, and they therefore exhibited the highest carcinogenic risk.

Air Pollutants, Radioactive↗
PubMed1995

Loads on spinal tissues during simultaneous lifting and ventilatory challenge.

Muscles of the torso have been implicated to play a role in stabilization of the low back, and to assist in ventilation. This motivated an investigation to combine a load challenge to the low back with a breathing challenge, similar to that which a worker might experience when shovelling snow. Perhaps modulation of muscle activity needed to facilitate breathing may compromise the margin of safety of tissues that depend on constant muscle activity for support. Eight young healthy males dynamically lifted, and isometrically held, large loads (73-95 kg) and breathed a 10% CO2 gas mixture to elevate breathing (both with and without hand-held loads). Individual tissue forces were calculated using an anatomically detailed, dynamic model of the torso that was sensitive to individual variation by utilizing myoelectric signals, intra-abdominal pressure, ventilation rate and spine kinematics, obtained from each subject, as input. For large loads in the hands, most subjects appeared to stabilize the trunk with large muscle forces relegating the responsibility of creating lung air flow to the diaphragm. When reasonably small low-back demands were coupled with a breathing challenge and higher ventilation rates two out of eight subjects demonstrated entrainment of abdominal activity to breathing that resulted in additional cyclic low-back compressive loading of the order of 1000 N. Ergonomists should consider the additional tissue loading from physiologically demanding tasks and the related ventilation challenge, together with the tissue loads required to support external objects and maintain body posture.

Adult↗
PubMed1998

Slip, trip and fall accidents occurring during the delivery of mail.

This study sought to identify causal factors for slip, trip and fall accidents occurring during the delivery of mail. Analysis of in-house data produced information about accident circumstances for 1734 fall cases. The most common initiating events in delivery falls were slips and trips. Slips most often occurred on snow, ice or grass, while trips tended to involve uneven pavements, obstacles and kerbs. Nearly one-fifth of falls occurred on steps, with step falls requiring longer absence from work than falls on the level. Half of all falls occurred during November-February and three-quarters of falls occurred between 7 and 9 a.m. Incidence rates for female employees were 50% higher than for their male colleagues. Accident-independent methods included interviews with safety personnel and managers, discussion groups with delivery employees, and a questionnaire survey of employees and managers. These techniques provided data on risk factors related to the task, behaviour, footwear and equipment. Arising from these accident-independent investigations, it is suggested that unsafe working practices, such as reading addresses while walking and taking shortcuts, increase the risk of falls. Organizational issues include management safety activities, training and equipment provision. Measures are discussed that might lead to a reduction in the incidence of delivery fall accidents.

Absenteeism↗
PubMed1991

Delusions and hallucinations of cocaine abusers and paranoid schizophrenics: a comparative study.

We compared delusions and hallucinations of 100 cocaine abusers and 100 paranoid schizophrenic subjects admitted to an East Texas state psychiatric hospital. Subjects in both groups feared that individuals or organized groups might harm them in some way, but delusions of the paranoid schizophrenic subjects were more often bizarre than those of the cocaine abuse subjects. "Cocaine bugs" (parasitosis) were more often found in the cocaine abuse subjects. Command hallucinations were found in both groups, but the commands of the schizophrenic group more often related to harming or killing others. Cocaine abusers had a greater frequency of visual hallucinations (47 to 7), distinguished by shadows, flashing lights ("snow lights"), objects moving and bugs crawling on the arm. Finally, the most distinguishing characteristics were identity delusions, possession delusions, grandiose delusions (other than identities and possessions), and delusions that their families were imposters (Capgras Syndrome) reported by paranoid schizophrenics. No such delusions were reported by the cocaine abusers.

Adolescent↗
PubMed1979

Primary care of ocular emergencies. 2. Thermal, chemical, and nontraumatic eye injuries.

First- and second-degree flash burns can be treated by the primary care physician, but third-degree burns will require a specialist for extensive debridement and skin grafting. Actinic keratitis, often associated with welding and snow skiing, is painful but can be treated with drugs in the office. There is no treatment for eclipse burn. Alkali is more toxic to the eye than is acid and can dill corneal epithelium and endothelium. All chemical burns require copious irrigation, but a patient with an alkali burn must be sent immediately thereafter to an ophthalmic surgeion. Acute glaucoma and acute occlusion of the central retinal artery are the two major nontraumatic eye emergencies. Patients with either of these injuries should be referred to a specialist after emergency measures have been taken.

Acute Disease↗
PubMedDate not supplied

The use of reminiscence therapy for the treatment of depression in rural-dwelling older adults.

This article explores the potential for the use of reminiscence therapy as an effective means of reducing depression among institutionalized, rural-dwelling elders, especially elderly women. Reminiscence therapy is a nurse-initiated intervention that has the advantages of being cost-effective, therapeutic, social, and recreational for the institutionalized older adult. As a communicative psychosocial process, reminiscence therapy has proven to be a valuable intervention for the depressed elderly client (Cully, LaVoie, & Gfeller, 2001; Haight & Hendrix, 1998; Haight, Michel, & Hendrix, 1998, 2000). It has been shown that depressed elders living in rural areas resist treatment from mental health services for a variety of different reasons (Molinari, Boeve, Kunik, & Snow-Turek, 1999; Neese, Abraham, & Buckwalter, 1999). For those elders, reminiscence therapy may prove an extremely beneficial alternative to more traditional treatment modalities in reducing the effects of depression and depressive symptoms.

Aged↗
PubMed2003

Energy cost of different skating techniques in cross-country skiing.

The aims of this study were to compare the aerobic energy cost of four 'on-snow' skating techniques in cross-country skiing and to examine the relationships between performance and aerobic energy cost. Twelve male skiers from recreational to national standard performed four level skating trials of 6 min duration in random order, each at the same submaximal velocity but with a different skating technique: (1) 'offset' (V1), using a double asymmetrical and asynchronous pole plant as weight is transferred to one ski; (2) 'two-skate' (V2A), where the pole plant is symmetrical; (3) 'one-skate' (V2), where there is a pole plant as weight is transferred to each ski; and (4) 'conventional', without poles. Oxygen uptake (VO2), pulmonary ventilation, the respiratory exchange ratio and heart rate were measured using a K4(b2) portable gas analyser. The aerobic energy cost (VO2/mean speed) and heart rate were higher (P < 0.05) in the one-skate than in the offset condition. This may be explained by the greater and more efficient use of the upper body and the lower variation in centre of gravity velocity in the offset condition. The aerobic energy cost was 5-9% higher (P < 0.01) in the conventional than in the other techniques, probably because of the shorter duration of propulsive forces within a cycle in the conventional skating condition. Moreover, in ski skating, the mechanical efficiency (propulsive forces/total forces) was shown to be higher in the upper than in the lower limbs. The correlation coefficient between performance and aerobic energy cost was significant in the two-skate (r = 0.68, P = 0.02), one-skate (r = 0.72, P = 0.01) and conventional (r = 0.62, P = 0.04) conditions, but not in the offset condition (r = 0.50, P = 0.10). Our results stress the importance of the upper body component in cross-country skiing and that the aerobic energy cost discriminates between skiers of different standards.

Adult↗
PubMed2003

Biomechanical aspects of new techniques in alpine skiing and ski-jumping.

There have been considerable changes in equipment design and movement patterns in the past few years both in alpine skiing and ski-jumping. These developments have been matched by methods of analysing movements in field conditions. They have yielded new insights into the skills of these specific winter sports. Analytical techniques have included electromyography, kinetic and kinematic methods and computer simulations. Our aim here is to review biomechanical research in alpine skiing and ski-jumping. We present in detail the techniques currently used in alpine skiing (carving technique) and ski-jumping (V-technique), primarily using data from the authors' own research. Finally, we present a summary of the most important results in biomechanical research both in alpine skiing and ski-jumping. This includes an analysis of specific conditions in alpine skiing (type of turn, terrain, snow, speed, etc.) and the effects of equipment, materials and individual-specific abilities on performance, safety and joint loading in ski-jumping.

Biomechanical Phenomena↗
PubMed1986

Influence of ski materials on muscle activity.

The purpose of this study was to examine whether differences in construction between the compact ski, the racing ski and the soft ski influence the behavioural and electromuscular responses of the user. Eight qualified male ski instructors performed two 'shuss' trials and three different basic turns. Six muscles (M. biceps femoris, M. gastrocnemius lateralis and medialis, M. rectus femoris, M. vastus lateralis and M. tibialis anterior) were studied, using a conventional but portable electromyographic (EMG) registration with telemetric synchronization, active electrodes and a six-channel portable data recorder. Muscle contractions were continuously registered and visualized in raw EMG form and linear envelopes. The differences between the mean rectified EMG data of dynamic contractions while skiing and the mean rectified EMG data of the maximal voluntary contraction were used in the primary analysis of data, from which the participation levels of the muscles investigated could be calculated for each type of ski. Based on this comparison, differences between the effects on muscle activity of the three types of skis were unimportant. In a second phase, the normalized linear envelopes of all subjects were graphically superimposed and averaged. This was performed for each muscle, for each movement, for each leg and for each ski tested. The EMG data were considered in combination with anthropometric values, with snow characteristics and with the velocity of skiing. This study showed systematic differences between the use of the racing, soft and compact ski. On average the soft ski showed the lowest muscle activity patterns and thus the most economical muscular efforts for all muscles investigated and within all movements.

Adult↗
PubMed1994

Ergonomic analyses of downhill skiing.

The purpose of this study was to provide electromyographic feedback for (1) pedagogical advice in motor learning, (2) the ergonomics of materials choice and (3) competition. For these purposes: (1) EMG data were collected for the Stem Christie, the Stem Turn and the Parallel Christie (three basic ski initiation drills) and verified for the complexity of patterns; (2) integrated EMG (iEMG) and linear envelopes (LEs) were analysed from standardized positions, motions and slopes using compact, soft and competition skis; (3) in a simulated 'parallel special slalom', the muscular activity pattern and intensity of excavated and flat snow conditions were compared. The EMG data from the three studies were collected on location in the French Alps (Tignes). The analog raw EMG was recorded on the slopes with a portable seven-channel FM recorder (TEAC MR30) and with pre-amplified bipolar surface electrodes supplied with a precision instrumentation amplifier (AD 524, Analog Devices, Norwood, USA). The raw signal was full-wave rectified and enveloped using a moving average principle. This linear envelope was normalized according to the highest peak amplitude procedure per subject and was integrated in order to obtain a reference of muscular intensity. In the three studies and for all subjects (elite skiers: n = 25 in studies 1 and 2, n = 6 in study 3), we found a high level of co-contractions in the lower limb extensors and flexors, especially during the extension phase of the ski movement. The Stem Christie and the Parallel Christie showed higher levels of rhythmic movement (92 and 84%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Electromyography↗
PubMed1997

Isolated fracture of the posterolateral tibial lip (Volkmann's triangle).

PURPOSE: To retrospectively evaluate the underlying pathomechanism of isolated fracture of the posterolateral tibial lip (Volkmann's triangle), and to demonstrate associated radiographic methods. MATERIAL AND METHODS: Retrospective analysis of 2500 ankle lesions showed an isolated fracture of the dorsal tibial lip in 25 cases. Distal tibial lesions of growing individuals were not considered. All patients were examined by radiography in internal oblique and lateral views. RESULTS: Sixteen of 25 patients had had their accident during winter; 11 had slipped on ice or snow. All 25 patients showed a closed ankle lesion in the correct joint position with no clinical signs of instability. Evaluation of the standard images showed isolated fracture of the posterolateral tibial lip in 24 patients. The fracture was best recognized in the standard lateral view in 22 patients. In 2 patients the lateral stress projection demonstrated the fracture (20 degrees internal rotation). In one case the fracture was only seen on axial CT images. Twenty-two patients with small wedge fragments were treated conservatively; 3 with a displaced and large fragment had surgical revision and stabilization. Sixteen cases were examined by conventional radiography at follow-up examination and 5 of these showed radiological signs of arthrosis. CONCLUSION: Plain conventional radiography is still necessary in the primary diagnosis of ankle joint lesions. The isolated fracture of the dorsal tibial margin is best seen in the standard lateral view. Indication for CT in routine diagnostics is limited to cases showing clinical evidence of ankle injury without roentgenological signs of a fracture in the standard images. Differential diagnoses include the pilon lesion and the Maison-neuve-type fracture.

Accidental Falls↗
PubMed1987

Determination of trialkyllead species in water samples.

An analytical compound procedure is described for the determination of trimethyl- and triethyllead in water samples like rain, melted snow, and surface waters. The method consists of an enrichment step (adsorption onto and elution from silica gel), a chromatographic separation with column switching (HPLC including pre-column enrichment), and a spectrophotometric detection (chemical reaction detector). The detection limits for the whole procedure, starting with 500 ml sample volume, are 15 pg/ml and 20 pg/ml for trimethyl- and triethyllead resp. The standard deviation for repeated analysis of a sample containing 90 pg Et3Pb+/ml is calculated to +/- 4%. The method also covers the analysis of the chemically mixed trialkyllead species Me2EtPb+ and MeEt2Pb+. The investigation of several water samples taken from different locations shows the presence of trimethyl- and triethyllead in the concentration range of 20-100 pg/ml.

Fresh Water↗
PubMed2006

Omitting details from post-event information: are true and false memory affected in the same way?

Participants who witness an event and later receive post-event information that omits a critical scene are less likely to recall and to recognise that scene than are participants who receive no post-event information (Wright, Loftus, & Hall, 2001). The present study used the Deese-Roediger-McDermott (DRM) paradigm, in which participants study lists of semantic associates (e.g., hot, snow, warm, winter) that commonly elicit false memories of critical non-presented words (e.g., cold), to determine whether omitting information from a second presentation decreases memory for both presented and non-presented information. Participants were presented with a list of the semantic associates of six non-presented words. For half the participants, this list was presented a second time with the semantic associates of one of the non-presented words omitted. As expected, participants were less likely to recall and to recognise the presented words when they had been omitted from the second presentation. Omission also decreased the rate at which non-presented words were recalled, although false recognition of these words was not reduced. These results suggest that false recognition may be particularly difficult to attenuate and that post-event omission may be more detrimental to memory accuracy than previously thought.

Adolescent↗
PubMedDate not supplied

How light reaches the eye and its components.

The human eye is exquisitely sensitive to light (i.e., visible radiant energy), and when dark-adapted, the retina can detect a few photons of blue-green light. It is therefore not at all surprising that ocular tissues are also more vulnerable to ultraviolet (UV) and light damage than the skin. For this reason, humans have evolved with certain anatomical, physiological, and behavioral traits that protect this critical organ from the UV damage that would otherwise be certain from the intense bath of overhead solar ultraviolet radiation (UVR) when we are outdoors during daylight. For example, the UV exposure threshold dose for photokeratitis ("welders' flash" or "snow blindness")--if measured as falling on a horizontal ground surface--would be reached in less than 10 minutes around midday in the summer sun. There are three critical ocular structures that could be affected by UV exposure: the cornea, the lens, and the retina. The cornea transmits radiant energy only at 295 nm and above. The crystalline lens absorbs almost all incident energy to wavelengths of nearly 400 nm. In youth, a very small amount of UV-A reaches the retina, but the lens becomes more absorbing with age. Thus there are intraocular filters that effectively filter different parts of the UV spectrum and allow only of the order of 1% or less to actually reach the retina. Nevertheless, this small fraction of energy--if phototoxic--could still be of concern. Finally, oblique rays entering the eye from the temporal side, can actually reach the equatorial (germinative) area of the lens.

Eye↗
PubMed2001

Use of Rtrade mark stent in the percutaneous coronary intervention of coronary bifurcation lesions.

BACKGROUND: Percutaneous Coronary Intervention (PCI) of coronary bifurcation lesion is technically quite demanding. It has been associated with a lower procedural success, higher rates of complication and restenosis. Side-branch occlusion and plaque shifting or 'snow plow' effect are not uncommon. Stenting of the main vessel may cause 'stent jail' of the side-branch. Modern stent design may allow passage of a balloon or stent into the side-branch through the struts of the stent placed in the main vessel. A newly developed 316 stainless steel tubular stent, the Rtrade mark stent is uniquely designed to provide flexibility, radial strength on deployment and conformability. Its large cell size facilitates PCI of bifurcation lesion. AIM: To assess the feasibility of R(trade mark) stent in the treatment of symptomatic patients with bifurcation coronary lesions. The main objective was to assess the ease of deployment, side-branch access and overall success of the R(trade mark) stent in this group of patients without any major adverse events. METHODS: Between December 1998 and September 2000 the R(trade mark) stent was used as a main stent in 28 consecutive patients with coronary bifurcation lesions, 46% of which had unstable angina. The mean age was 59 +/- 10 and 89% were male. Adjunctive medical therapy included clopidrogel, aspirin and intraprocedure heparin. Abciximab (ReoPro) was given to 9 patients. RESULTS: Successful stent deployment was achieved in all patients. Thirty-four R Stents and 16 other stents were used. Two patients had post-procedure rise in cardiac enzymes. There were no major adverse events at 30 days. LAD/D1 with LAD/diagonal was the target lesion in the majority of patients. Stenting of the side-branch was done in 18 and balloon dilatation in 9 patients. At 3-23 months (mean 11.8) follow-up, repeat angiography was done in 18 patients with restenosis in 4, two of them had repeat PCI and one had coronary artery bypass graft (CABG). CONCLUSION: Coronary bifurcation lesions are not uncommon. Current advances in stent technology offer a safe and effective revascularisation strategy for such complex lesions. The R(trade mark) stent appears to be a suitable device that provides good wall coverage, radial strength, conformability and easy side-branch access.

Journal Article↗
PubMed2006

Management of respiration in MND/ALS patients: an evidence based review.

This systematic review comprises an objective appraisal of the evidence in regard to the management of respiration in patients with motor neuron disease (MND/ALS). Studies were identified through computerised searches of 32 databases. Internet searches of websites of drug companies and MND/ALS research web sites, 'snow balling' and hand searches were also employed to locate any unpublished study or other 'grey literature' on respiration and MND/ALS. Since management of MND/ALS involves a number of health professionals and care workers, searches were made across multiple disciplines. No time frame was imposed on the search in order to increase the probability of identifying all relevant studies, although there was a final limit of March 2005. Recommendations for patient and carer-based guidelines for the clinical management of respiration for MND/ALS patients are suggested on the basis of qualitative analyses of the available evidence. However, these recommendations are based on current evidence of best practice, which largely comprises observational research and clinical opinion. There is a clear need for further evidence, in particular randomised and non-randomised controlled trials on the effects of non-invasive ventilation and additional larger scale cohort studies on the issues of initial assessment of respiratory symptoms, and management and timing of interventions.

Amyotrophic Lateral Sclerosis↗
PubMed2004

The effectiveness of ESP (Electronic Stability Program) in reducing real life accidents.

ESP (Electronic Stability Program) has recently been introduced onto the market in an effort to reduce the number and severity of loss-of-control automobile accidents. This reduction is expected to be particularly evident for accidents on roads with low friction (e.g., wet or icy conditions). This study aimed to evaluate the statistical effectiveness of ESP using data from accidents that occurred in Sweden during 2000 to 2002. To control for exposure, induced exposure methods were used, where ESP-sensitive to ESP-insensitive accidents and road conditions were matched in relation to cars equipped with and without ESP. Cars of similar, or in some cases identical, make and model were used to isolate the role of ESP. As predicted, the study showed a positive effect of ESP in circumstances where road surfaces have low friction. The overall effectiveness was 22.1 (+/-21) percent, while for accidents on wet roads, the effectiveness increased to 31.5 (+/-23.4) percent. On roads covered with ice and snow, the corresponding effectiveness was 38.2 (+/-26.1) percent. In addition, ESP was found to be effective for three different types of cars: small front-wheel drive; large front-wheel drive; and large rear-wheel drive.

Accidents, Traffic↗