A coexisting anatomic variation of median and ulnar nerves in a cadaver palm

During a routine dissection we observed an anatomical variation of the median nerve and an atypical anastomosis in the palm region of a male cadaver. There were four distinct recurrent motor branches of the left median nerve and the palmar cutaneous branch of the ulnar nerve communicated directly with the third common palmar digital nerve. The presence of such anatomical variant in the hand should keep surgeons alert in the management of hand pathology especially in carpal tunnel syndrome which is a routine operation for many medical centers

Environmental concentrations of antifouling paint particles are toxic to sediment-dwelling invertebrates

Antifouling paint particles (APPs) and associated metals have been identified in sediments around boatyards and marinas globally, but the effects of APPs on benthic organisms are largely unknown. Sub-lethal endpoints were measured following laboratory exposures of the harbour ragworm (Hediste diversicolor) and the common cockle (Cerastoderma edule) to environmentally relevant concentrations of biocidal (‘modern’ and ‘historic’) and biocide-free (‘silicone’) APPs added to clean estuarine sediment. Further, the 5-day median lethal concentrations (LC50) and effects concentrations (EC50) for modern biocidal APPs were calculated. For ragworms, significant decreases in weight (15.7%; p < 0.01) and feeding rate (10.2%; p < 0.05) were observed in the modern biocidal treatment; burrowing behaviour was also reduced by 29% in this treatment, but was not significant. For cockles, the modern biocidal treatment led to 100% mortality of all replicates before endpoints were measured. In cockles, there was elevated levels of metallothionein-like protein (MTLP) in response to both modern and historic biocidal treatments. Ragworms had a higher tolerance to modern APPs (5-day LC50:19.9 APP g L−1; EC50: 14.6 g L−1) compared to cockles (5-day LC50: 2.3 g L−1 and EC50: 1.4 g L−1). The results of this study indicate that modern biocidal APPs, containing high Cu concentrations, have the potential to adversely affect the health of benthic organisms at environmentally relevant concentrations. The findings highlight the need for stricter regulations on the disposal of APP waste originating from boatyards, marinas and abandoned boats

Antifouling paint particles in intertidal estuarine sediments from southwest England and their ingestion by the harbour ragworm, Hediste diversicolor

© 2019 Antifouling paint particles (APPs) of between 500 μm and >2 mm in diameter have been identified in silty, intertidal estuarine sediments through a combination of microscopy and x-ray fluorescence spectrometry. APPs were heterogeneously distributed, with maximal concentrations of 430 particles L −1 (0.2 g L −1 ) near to a facility where boats are regularly maintained and 400 particles L −1 (4.2 g L −1 ) at a location where old boats had been abandoned, with the majority of particles encountered in the finest size fraction retrieved. APPs contained variable concentrations of Cu, Zn, Sn and Pb, with respective maxima of 562,000, 269,000, 9,970 and 126,000 mg kg −1 . These characteristics are attributed to a multitude of contemporary and historic sources of an assortment of formulations and result in significant but heterogeneous metal contamination of local sediments. APPs were also identified in the guts of the deposit-feeding ragworm, Hediste diversicolor, that inhabited sediments impacted by abandoned boats or boating activities. The tissue of H. diversicolor was particularly enriched in Cu where ingested APPs were observed, with a significant correlation between dry weight Cu concentrations in the two media (r = 0.734) presumably reflecting the inability of the animal to regulate this metal. While the toxicity of APPs requires further investigation, there is clearly a need for stricter regulations on antifouling wastes in boatyards and marinas and a requirement to better manage abandoned boats. Antifouling paint particles in contaminated estuarine sediments can be ingested by Hediste diversicolor and result in the bioaccumulation of copper

Time-varying correlations and interrelations:Firm-level-based sector evidence

Using firm-level data, we examine stock market correlations and interrelations for the G7 over the period 2000–2013. An examination using aggregate market data supports the view that correlations have risen and particularly so during crisis periods. Using firm-level data, which is tradeable, we establish sector portfolios. We consider three regression approaches. The results support, first, that correlations using firm data are lower than those observed using aggregate market index data. Second, the most important driver for home sector returns is the home market followed by the corresponding US sector. Third, correlations rose during the crisis but have stabilised and even fallen since. This supports the view that markets fall together but rise apart. Fourth, there is evidence that most sector correlations follow a market-wide component, but some sector correlations follow their own component. Subsequently, we examine the key drivers of time-varying correlations. We find that the market-wide component of correlations increases in a US bear market as well as with higher US market volatility and lower US interest rates. However, on a sector basis, there are notable exceptions with some correlations falling in a bear market. Together, these results support the view that diversification benefits remain across market sectors