Wednesday, 1 April 2009

Are full or empty beer bottles sturdier and does their fracture-threshold suffice to break the human skull?

Journal of Forensic and Legal Medicine
Volume 16, Issue 3, April 2009, Pages 138–142

Stephan A. Bolliger, MD (Senior Forensic Pathologist), Steffen Ross, MD (Radiologist), Lars Oesterhelweg, MD (Forensic Pathologist), Michael J. Thali, MD (Professor, Director, Forensic Pathologist), Beat P. Kneubuehl, PhD (Physicist)

Centre for Forensic Imaging and Virtopsy, Institute of Forensic Medicine, University of Bern, IRM, Buehlstrasse 20, CH-3012 Bern, Switzerland

Abstract

Beer bottles are often used in physical disputes. If the bottles break, they may give rise to sharp trauma. However, if the bottles remain intact, they may cause blunt injuries. In order to investigate whether full or empty standard half-litre beer bottles are sturdier and if the necessary breaking energy surpasses the minimum fracture-threshold of the human skull, we tested the fracture properties of such beer bottles in a drop-tower.

Full bottles broke at 30 J impact energy, empty bottles at 40 J. These breaking energies surpass the minimum fracture-threshold of the human neurocranium. Beer bottles may therefore fracture the human skull and therefore serve as dangerous instruments in a physical dispute.

Keywords

Breaking energy threshold; Beer bottles; Blunt head trauma

http://www.sciencedirect.com/science/article/pii/S1752928X08001728

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Sunday, 1 March 2009

Earwax (cerumen) might be formulated into a safe and biodegradable insect repellent

Medical Hypotheses
Volume 72, Issue 3 , Pages 370-371, March 2009
doi: 10.1016/j.mehy.2008.09.036

Somaieh Ahmadian, Mohammad Amin Abolghassemi Fakhree

Research Center for Pharmaceutical Nanotechnology, Tabriz University (Medical Sciences), Daneshgah Street, Tabriz, Iran
Gifted and Talented Students Office, Educational Development Center, Tabriz University (Medical Sciences), Tabriz, Iran

Some of the most common life threatening insect-borne diseases include malaria, leshmaniasis and yellow fever which can be prevented or treated with different non-therapeutic/therapeutic procedures such as use of mosquito net, insect repellent (IR), vector controlling strategies, vaccination and implementation of pharmaceuticals. Among these methods IR provides the cheapest and easiest one to use. Active ingredients of IR usually include N,N-diethyl-3-methylbenzamide (DEET), botanical extracts and picaridin. However still some concerns remain e.g. DEET is not biodegradable, has side effects on skin, cardiovascular and central nervous system and is not applicable in under 3 years old children and animals.

Cerumen is produced by glands that are located on the outer third of the ear canal, has a characteristic of bitter taste and protection of ear which is known as IR, bactericide, fungicide and antivirus. It has lipidic and non-lipidic fractions; lipid fraction is consisted of squalene, cholesterol esters, wax esters, triacylglycerols, fatty acids, cholesterol, ceramides, cholesterol sulfate, and several unidentified polar components.

The authors would like to hypothesize an IR made from fatty acids and steroids of cerumen. Whereas masking skin odor and presenting a bad taste is the mechanism of action for IRs. Also fatty acids considered as major ingredient of Neem Oil as repellent, a screening of lipid fraction with the aim of discovering which components have the major effect is recommended.

The advantages of the proposed formulation will be easy of production, biodegradability and safety of use in adults, children and animals.

Beside, proteins and peptides in cerumen could be further analyzed in order to investigate a nontoxic multi-spectrum antibiotic; possessing bactericidal, fungicidal and antiviral activity.

http://www.medical-hypotheses.com/article/S0306-9877%2808%2900500-8/abstract

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Thursday, 15 January 2009

Effects of cocaine on honey bee dance behaviour

J Exp Biol
Jan 15, 2009; 212(2): 163–168
doi:  10.1242/jeb.025361

Andrew B. Barron [1,2,*], Ryszard Maleszka [1], Paul G. Helliwell [1] and Gene E. Robinson [2]

[1] ARC Centre for Molecular Genetics of Development, Research School of Biological Sciences, Australian National University, Canberra, ACT 2601, Australia
[2] Department of Entomology and Neuroscience Program, University of Illinois at Urbana-Champaign, 505 S. Goodwin Avenue, Urbana, IL 61801, USA

* Author for correspondence at present address: Centre for the Integrative Study of Animal Behaviour, Macquarie University, Sydney NSW 2109, Australia

Summary

The role of cocaine as an addictive drug of abuse in human society is hard to reconcile with its ecological role as a natural insecticide and plant-protective compound, preventing herbivory of coca plants (Erythroxylum spp.). This paradox is often explained by proposing a fundamental difference in mammalian and invertebrate responses to cocaine, but here we show effects of cocaine on honey bees (Apis mellifera L.) that parallel human responses. Forager honey bees perform symbolic dances to advertise the location and value of floral resources to their nest mates. Treatment with a low dose of cocaine increased the likelihood and rate of bees dancing after foraging but did not otherwise increase locomotor activity. This is consistent with cocaine causing forager bees to overestimate the value of the floral resources they collected. Further, cessation of chronic cocaine treatment caused a withdrawal-like response. These similarities likely occur because in both insects and mammals the biogenic amine neuromodulator systems disrupted by cocaine perform similar roles as modulators of reward and motor systems. Given these analogous responses to cocaine in insects and mammals, we propose an alternative solution to the paradox of cocaine reinforcement. Ecologically, cocaine is an effective plant defence compound via disruption of herbivore motor control but, because the neurochemical systems targeted by cocaine also modulate reward processing, the reinforcing properties of cocaine occur as a `side effect'.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2720998/

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Wednesday, 17 December 2008

Head and neck injury risks in heavy metal: head bangers stuck between rock and a hard bass

BMJ. 2008; 337: a2825
Published online Dec 17, 2008
doi:  10.1136/bmj.a2825

Declan Patton, research assistant
Andrew McIntosh, associate professor

School of Risk and Safety Sciences, University of New South Wales, Sydney, Australia 2052

Objective To investigate the risks of mild traumatic brain injury and neck injury associated with head banging, a popular dance form accompanying heavy metal music.

Design

Observational studies, focus group, and biomechanical analysis.

Participants

Head bangers.

Main outcome measures

Head Injury Criterion and Neck Injury Criterion were derived for head banging styles and both popular heavy metal songs and easy listening music controls.

Results

An average head banging song has a tempo of about 146 beats per minute, which is predicted to cause mild head injury when the range of motion is greater than 75°. At higher tempos and greater ranges of motion there is a risk of neck injury.

Conclusion

To minimise the risk of head and neck injury, head bangers should decrease their range of head and neck motion, head bang to slower tempo songs by replacing heavy metal with adult oriented rock, only head bang to every second beat, or use personal protective equipment.

http://www.bmj.com/content/337/bmj.a2825?view=long&pmid=19091761

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