Functional and developmental studies of the peripheral arterial chemoreceptors in rat: effects of nicotine and possible relation to sudden infant death syndrome.

The drive on respiration mediated by the peripheral arterial chemoreceptors was assessed by the hyperoxic test in 3-day-old rat pups. They accounted for 22.5 +/- 8.8% during control conditions, but only for 6.9 +/- 10.0% after nicotine exposure, an effect counteracted by blockade of peripheral dopamine type 2 receptors (DA2Rs). Furthermore, nicotine reduced dopamine (DA) content and increased the expression of tyrosine hydroxylase (TH) in the carotid bodies, further suggesting that DA mediates the acute effect of nicotine on arterial chemoreceptor function. During postnatal development TH and DA2R mRNA levels in the carotid bodies decreased. Thus, nicotine from smoking may also interfere with the postnatal resetting of the oxygen sensitivity of the peripheral arterial chemoreceptors by increasing carotid body TH mRNA, as well as DA release in this period. Collectively these effects of nicotine on the peripheral arterial chemoreceptors may increase the vulnerability to hypoxic episodes and attenuate the protective chemoreflex response. These mechanisms may underlie the well-known relation between maternal smoking and sudden infant death syndrome.

Tunnel magnetoresistance in GaMnAs: going beyond Jullière formula

The relation between tunnel magnetoresistance (TMR) and spin polarization is explored for GaMnAs∕GaAlAs∕GaMnAs structures where the carriers experience strong spin–orbit interactions. TMR is calculated using the Landauer approach. The materials are described in the 6 band k⋅p model which includes spin–orbit interaction. Ferromagnetism is described in the virtual crystal mean field approximations. Our results indicate that TMR is a function of spin polarization and barrier thickness. As a result of the stong spin–orbit interactions, TMR also depends on the the angle between current flow direction and the electrode magnetization. These results compromise the validity of Julliere formula.

Measuring color differences in automotive samples with lightness flop: a test of the AUDI2000 color-difference formula

From a set of gonioapparent automotive samples from different manufacturers we selected 28 low-chroma color pairs with relatively small color differences predominantly in lightness. These color pairs were visually assessed with a gray scale at six different viewing angles by a panel of 10 observers. Using the Standardized Residual Sum of Squares (STRESS) index, the results of our visual experiment were tested against predictions made by 12 modern color-difference formulas. From a weighted STRESS index accounting for the uncertainty in visual assessments, the best prediction of our whole experiment was achieved using AUDI2000, CAM02-SCD, CAM02-UCS and OSA-GP-Euclidean color-difference formulas, which were no statistically significant different among them. A two-step optimization of the original AUDI2000 color-difference formula resulted in a modified AUDI2000 formula which performed both, significantly better than the original formula and below the experimental inter-observer variability. Nevertheless the proposal of a new revised AUDI2000 color-difference formula requires additional experimental data.

A partial success of trade cooperation within the ‘16+1’ formula: the case of food exports to China. OSW COMMENTARY #189, 2015-10-29

When in 2012 China approached the countries of Central and Eastern Europe (CEE) with a proposal of cooperation in the ‘16+1’ formula, it declared it was willing to meet the needs of CEE countries. Beijing had been aware of the political importance of the problem of trade deficit (which has been ongoing for years) and launched cooperation with the governments of 16 CEE countries to boost imports from these states. The years 2011–2014 brought an improvement in the balance of trade between China and: Hungary, Latvia, the Czech Republic, Romania, Bulgaria and Croatia. The remaining ten CEE countries recorded an increase in their trade deficits. Changes in CEE countries’ balance of trade with China resulted only slightly from political actions. Instead, they were due to the macroeconomic situation and to a deterioration of the debt crisis in the EU which, for example, caused a decline in the import of Chinese goods in some of these countries. Multilateral trade cooperation was successfully developed in the entire region only in the agricultural and food production sector – the area of greatest interest to China. The pace of bilateral cooperation with specific countries varied, with the fastest being Poland, Latvia, Romania, Hungary and Bulgaria. Actions by governments of CEE countries resulted in Chinese market opening up to hundreds of local companies which, in turn, translated into an increase in the volume of foodstuffs sold by ‘the 16’ to China from US$ 137 million in 2011 to US$ 400 million in 2014. The success achieved in the agricultural and food production sector has demonstrated the effectiveness of trade cooperation in the ‘16+1’ formula. It is, however, insufficient to generate a significant improvement of the trade balance. At present, the sector’s share in the total volume of goods sold to China by CEE states is a mere 3.7%, and any reduction of the trade deficit would require long-term and more comprehensive solutions still to be implemented by the governments of individual CEE states.

China’s foreign direct investments within the ‘16+1’ cooperation formula: strategy, institutions, results. OSW Commentary Number 191|27.11.2015

The ‘16+1’ formula of cooperation between the countries of Central and Eastern Europe (CEE) and China was launched in 2012. One of its priorities involved increasing the inflow of China’s foreign direct investments (FDI) to the region. China has been interested in carrying out investments which are likely to help Chinese companies gain competitive advantage in areas such as advanced technologies, recognizable brands and distribution channels. The following sectors were identified as areas of priority importance in CEE: construction and modernisation of transport infrastructure, including motorways; development of the network of railways, airports and sea ports; energy, in particular renewable sources of energy and nuclear energy; companies trading in commodities; the food production sector. China’s strategy mainly involves purchasing existing companies, preceded by cherry picking the most favourable candidates for investment, rather than making large greenfield investments.

Inhibition of Hippocampal Regeneration by Adjuvant Dexamethasone in Experimental Infant Rat Pneumococcal Meningitis

Pneumococcal meningitis (PM) causes neurological sequelae in up to half of surviving patients. Neuronal damage associated with poor outcome is largely mediated by the inflammatory host response. Dexamethasone (DXM) is used as an adjuvant therapy in adult PM, but its efficacy in the treatment of pneumococcal meningitis in children is controversially discussed. While DXM has previously been shown to enhance hippocampal apoptosis in experimental PM, its impact on hippocampal cell proliferation is not known. This study investigated the impact of DXM on hippocampal proliferation in infant rat PM. Eleven-day-old nursing Wistar rats (n = 90) were intracisternally infected with Streptococcus pneumoniae to induce experimental meningitis. Treatment with DXM or vehicle was started 18 h after infection, concomitantly with antibiotics (ceftriaxone 100 mg/kg of body weight twice a day [b.i.d.]). Clinical parameters were monitored, and the amount of cells with proliferating activity was assessed using in vivo incorporation of bromodeoxyuridine (BrdU) and an in vitro neurosphere culture system at 3 and 4 d postinfection. DXM significantly worsened weight loss and survival. Density of BrdU-positive cells, as an index of cells with proliferating activity, was significantly lower in DXM-treated animals compared to vehicle controls (P < 0.0001). In parallel, DXM reduced neurosphere formation as an index for stem/progenitor cell density compared to vehicle treatment (P = 0.01). Our findings provide clear evidence that DXM exerts an antiproliferative effect on the hippocampus in infant rat PM. We conclude that an impairment of regenerative hippocampal capacity should be taken into account when considering adjuvant DXM in the therapeutic regimen for PM in children.