Environmental occurrence, analysis, and toxicology of toxaphene compounds.

Toxaphene production, in quantities similar to those of polychlorinated biphenyls, has resulted in high toxaphene levels in fish from the Great Lakes and in Arctic marine mammals (up to 10 and 16 microg g-1 lipid). Because of the large variabiliity in total toxaphene data, few reliable conclusions can be drawn about trends or geographic differences in toxaphene concentrations. New developments in mass spectrometric detection using either negative chemical ionization or electron impact modes as well as in multidimensional gas chromatography recently have led researchers to suggest congener-specific approaches. Recently, several nomenclature systems have been developed for toxaphene compounds. Although all systems have specific advantages and limitations, it is suggested that an international body such as the International Union of Pure and Applied Chemistry make an attempt to obtain uniformity in the literature. Toxicologic information on individual chlorobornanes is scarce, but some reports have recently appeared. Neurotoxic effects of toxaphene exposure such as those on behavior and learning have been reported. Technical toxaphene and some individual congeners were found to be weakly estrogenic in in vitro test systems; no evidence for endocrine effects in vivo has been reported. In vitro studies show technical toxaphene and toxaphene congeners to be mutagenic. However, in vivo studies have not shown genotoxicity; therefore, a nongenotoxic mechanism is proposed. Nevertheless, toxaphene is believed to present a potential carcinogenic risk to humans. Until now, only Germany has established a legal tolerance level for toxaphene--0.1 mg kg-1 wet weight for fish

Central effects of atropine upon aversive classical conditioning in rabbits

Rabbits were given classical discrimination conditioning with one of two tones followed by shock. In Experiment I, 40 rabbits were trained under saline, 10, 18 or 26 mg/kg atropine sulfate or 18 mg/kg methylatropine. Six rabbits in Experiment 2 were conditioned, then given further sessions with saline, and 18, 26 and 34 mg/kg atropine sulfate and methylatropine. In Experiment 3, 18 rabbits were conditioned and then given two extinction sessions under saline or 34 mg/kg atropine sulfate or methylatropine followed by extinction under saline. Chief findings were (a) atropine sulfate but not methylatropine disrupted acquisition and maintenance of conditioned eyeblinks, (b) neither drug affected unconditioned blinks, (c) fewer blinks occurred in extinction under atropine sulfate than under methylatropine or saline, (d) rabbits extinguished under atropine sulphate showed higher percentages of eyeblinks when tested without drug. Disruptions in performance of learned eyeblink responses appeared to be due to drug interference with central cholinergic transmission.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46381/1/213_2004_Article_BF00406735.pd

Understanding acute ankle ligamentous sprain injury in sports

This paper summarizes the current understanding on acute ankle sprain injury, which is the most common acute sport trauma, accounting for about 14% of all sport-related injuries. Among, 80% are ligamentous sprains caused by explosive inversion or supination. The injury motion often happens at the subtalar joint and tears the anterior talofibular ligament (ATFL) which possesses the lowest ultimate load among the lateral ligaments at the ankle. For extrinsic risk factors to ankle sprain injury, prescribing orthosis decreases the risk while increased exercise intensity in soccer raises the risk. For intrinsic factors, a foot size with increased width, an increased ankle eversion to inversion strength, plantarflexion strength and ratio between dorsiflexion and plantarflexion strength, and limb dominance could increase the ankle sprain injury risk. Players with a previous sprain history, players wearing shoes with air cells, players who do not stretch before exercising, players with inferior single leg balance, and overweight players are 4.9, 4.3, 2.6, 2.4 and 3.9 times more likely to sustain an ankle sprain injury. The aetiology of most ankle sprain injuries is incorrect foot positioning at landing – a medially-deviated vertical ground reaction force causes an explosive supination or inversion moment at the subtalar joint in a short time (about 50 ms). Another aetiology is the delayed reaction time of the peroneal muscles at the lateral aspect of the ankle (60–90 ms). The failure supination or inversion torque is about 41–45 Nm to cause ligamentous rupture in simulated spraining tests on cadaver. A previous case report revealed that the ankle joint reached 48 degrees inversion and 10 degrees internal rotation during an accidental grade I ankle ligamentous sprain injury during a dynamic cutting trial in laboratory. Diagnosis techniques and grading systems vary, but the management of ankle ligamentous sprain injury is mainly conservative. Immobilization should not be used as it results in joint stiffness, muscle atrophy and loss of proprioception. Traditional Chinese medicine such as herbs, massage and acupuncture were well applied in China in managing sports injuries, and was reported to be effective in relieving pain, reducing swelling and edema, and restoring normal ankle function. Finally, the best practice of sports medicine would be to prevent the injury. Different previous approaches, including designing prophylactice devices, introducing functional interventions, as well as change of games rules were highlighted. This paper allows the readers to catch up with the previous researches on ankle sprain injury, and facilitate the future research idea on sport-related ankle sprain injury

Engaging audiences with difficult pasts: the Voices of ’68 Project at the Ulster Museum, Belfast

Can history museums influence the relationship between divided communities? This paper explores why an initially modest collaboration between the authors and the Ulster Museum on the non‐violent Northern Ireland Civil Rights Movement of 1968/69, eventually had substantial impact beyond the museum’s walls. Having placed the Northern Ireland Civil Rights Movement within the context of both the international protests of 1968 and the specific environment of Northern Ireland, particularly the virtual civil war known as the Troubles, the paper turns to the role of museums in responding to the legacy of this past, and the evolving practice of the Ulster Museum, as background to the project. The latter began as a limited intervention within an existing display, based on oral histories and underpinned by the theory of ‘agonism’, proposing that divided communities must learn to live with difference. It eventually included exhibitions, workshops, school study days, curricular materials and online provision. It has directly influenced the Northern Ireland GCSE History Curriculum and been held up as an example of good practice within the province’s peace process. The paper discusses why the project succeeded – location within a national museum; credibility with protagonists, academics, communities and audiences; starting small; a willingness to take risks and share control; multiple perspectives; and an acceptance that not everyone will be satisfied. With a version of the Voices of 68 exhibition now installed in the Museum’s permanent gallery, the next challenges are longitudinal studies on its impact and assessing the approach’s relevance to other museums working in post‐conflict societies

Managing potential conflicts in the South China Sea

Since 1990 a series of informal meetings on the South China Sea has been sponsored by Canada and Indonesia. Rather than adopting an academic approach to the South China Sea, the meetings are attended by government officials from the region in their private capacities. The project proceeds on the assumption that resolution of territorial and jurisdictional disputes in the region is not possible without first addressing cooperation on other levels such as navigation and the environment. This paper examines progress made on these and other issues during 1993, and prospects for the future.

BLOOD TYPING BEEFALO CATTLE

In this article we review the species-specific genetic markers in the blood that are currently being used to authenticate the bison ancestry of animals entering the Ancestry Registry of the American Beefalo World Registry. Independently of that program we are also testing for these same genetic markers in a number of private herds in which attempts are being made to develop bison-cattle hybrids that are fully fertile and incorporate desirable traits of both ancestral species