Dopamine and semantic activation: An investigation of masked direct and indirect priming

To investigate the effects of dopamine on the dynamics of semantic activation, 39 healthy volunteers were randomly assigned to ingest either a placebo (n = 24) or a levodopa (it = 16) capsule. Participants then performed a lexical decision task that implemented a masked priming paradigm. Direct and indirect semantic priming was measured across stimulus onset asynchronies (SOAs) of 250, 500 and 1200 ms. The results revealed significant direct and indirect semantic priming effects for the placebo group at SOAs of 250 ms and 500 ms, but no significant direct or indirect priming effects at the 1200 ms SOA. In contrast, the levodopa group showed significant direct and indirect semantic priming effects at the 250 ms SOA, while no significant direct or indirect priming effects were evident at the SOAs of 500 ins or 1200 ms. These results suggest that dopamine has a role in modulating both automatic and attentional aspects of semantic activation according to a specific time course. The implications of these results for current theories of dopaminergic modulation of semantic activation are discussed

Patterns of abundance across geographical ranges as a predictor for responses to climate change: Evidence from UK rocky shores

Aim: Understanding patterns in the abundance of species across thermal ranges can give useful insights into the potential impacts of climate change. The abundant-centre hypothesis suggests that species will reach peak abundance at the centre of their thermal range where conditions are optimal, but evidence in support of this hypothesis is mixed and limited in geographical and taxonomic scope. We tested the applicability of the abundant-centre hypothesis across a range of intertidal organisms using a large, citizen science-generated data set. Location: UK. Methods: Species' abundance records were matched with their location within their thermal range. Patterns in abundance distribution for individual species, and across aggregated species abundances, were analysed using Kruskal–Wallis tests and quantile general additive models. Results: Individually, invertebrate species showed increasing abundances in the cooler half of the thermal range and decreasing abundances in the warmer half of the thermal range. The overall shape for aggregated invertebrate species abundances reflected a broad peak, with a cool-skewed maximum abundance. Algal species showed little evidence for an abundant-centre distribution individually, but overall the aggregated species abundances suggested a hump-backed abundance distribution

Does the Millennium Challenge Corporation reinforce capitalist power structures or empower citizens?

In development practice, how does ‘mutual benefit’ accrue, and to whom? China criticises America for perpetuating capitalist power relations and claims it can seek a new geo-political order based on South-South cooperation. Meanwhile, there has been an extraordinary shift of emphasis toward the private sector as a driver of development, but this shift is attracting increasing criticism. The Millennium Challenge Corporation (MCC) - the only development agency to grow in influence under the Trump administration - is evaluated in the light of these two key themes. Neither China nor the private sector are successful in achieving ‘mutual benefit’ for ordinary citizens – both replicate existing power inequalities. As with the rise of both China and the private sector, the MCC also enmeshes developing countries further into the existing neoliberal capitalist structures. However, the advantages of the agency should not be dismissed outright, as its Ruling Justly and Investing in People indicators can enhance the capacity of citizens to challenge these power structures themselves

Insights into the chemical composition of Equisetum hyemale by high resolution Raman imaging

Equisetaceae has been of research interest for decades, as it is one of the oldest living plant families, and also due to its high accumulation of silica up to 25% dry wt. Aspects of silica deposition, its association with other biomolecules, as well as the chemical composition of the outer strengthening tissue still remain unclear. These questions were addressed by using high resolution (<1 μm) Confocal Raman microscopy. Two-dimensional spectral maps were acquired on cross sections of Equisetum hyemale and Raman images calculated by integrating over the intensity of characteristic spectral regions. This enabled direct visualization of differences in chemical composition and extraction of average spectra from defined regions for detailed analyses, including principal component analysis (PCA) and basis analysis (partial least square fit based on model spectra). Accumulation of silica was imaged in the knobs and in a thin layer below the cuticula. In the spectrum extracted from the knob region as main contributions, a broad band below 500 cm−1 attributed to amorphous silica, and a band at 976 cm−1 assigned to silanol groups, were found. From this, we concluded that these protrusions were almost pure amorphous, hydrated silica. No silanol group vibration was detected in the silicified epidermal layer below and association with pectin and hemicelluloses indicated. Pectin and hemicelluloses (glucomannan) were found in high levels in the epidermal layer and in a clearly distinguished outer part of the hypodermal sterome fibers. The inner part of the two-layered cells revealed as almost pure cellulose, oriented parallel along the fiber

Uzbekistan’s development experiment: An assessment of Karimov’s peculiar economic legacy

Uzbekistan’s unique post-independence experiment with development was led by Islam Karimov until his sudden death in September 2016. Despite defying international advice on structural reforms, under Karimov’s rule, Uzbekistan achieved an average annual growth rate of 5% in the period 1996–2016, which was particularly impressive (over 8%) in 2004–2016. Karimov also left behind strong macroeconomic fundamentals for his successor. Since taking over the presidency in December 2016, Shavkat Mirziyoyev has introduced wide-ranging reforms, creating an impression of a de facto start to transition in Uzbekistan. This study analyses Karimov’s economic legacy and assesses whether it has enabled or hindered the developmental targets set by his successor