Amidst a now extensive literature on the imputed decline of party in Western democracies, particular emphasis has been placed on the theme of organisational decline, and on the supposed erosion of the organisational links which tie parties to electors. Much of this emphasis, inevitably, has been impressionistic, since, at least up to now, there has been a notable absence of systematic, cross-nationally comparable data on the development of party organisations over time. And while this general absence has been bemoaned at regular intervals by students of comparative party politics, regret has been most often focussed on the absence of cross-nationally comparable data concerning the development of party memberships, since it is these particular data which have generally been regarded - if not always appropriately (Katz & Mair, 1990) - as providing the most direct indicator of party organisational hold.

Liquid water at the ground–snow interface is thought to play a crucialrole in the release of glide-snow avalanches, which can be massive and threateninfrastructure in alpine regions. Several mechanisms have been postulated toexplain the formation of this interfacial water. However, these mechanismsremain poorly understood, in part because suitable measurement techniques arelacking. Here, we demonstrate the use of neutron radiography for imaging watertransport in soil–snow systems. Columns of sand, gravel and snow wereused to simulate the capillary forces of the soil–vegetation–snowlayering found in nature. The columns were connected to a water reservoir tomaintain a constant-pressure boundary condition and placed in a climatic chamberwithin the neutron beam. We show that neutron radiography is capable ofmeasuring changes in the optical density distribution (related to liquid watercontent) within all three layers of the model system. Results suggest that aporous interface between the sand and snow may induce the formation of a waterlayer in the basal snowpack. Improved understanding of the water transport insoil–snow systems should lead to better prediction of glide-snowavalanche release and could also benefit other fields such as snowhydrology.

The dynamics of the Greenland Ice Sheet are affected by surface meltwater reaching the base of the ice, altering ice contact with the bedrock. Lack of understanding of this evolution hampers the ability to predict the effects of increasing temperatures on the Greenland Ice Sheet mass balance. Here we present a unique high-resolution study of ice velocity response to surface melting based on data from a COSMO-SkyMed satellite campaign over Upernavik Isstrøm (Northwest Greenland) for two months around the end of the 2014 melt season. We show that the velocity variations, due to both short-term (days) and seasonal variations in surface melt rates, are increasing in relative strength farther from the glacier terminus. Furthermore, we observe how ice dynamic response to frontal retreat, reaching several kilometres inland, can obscure the meltwater-induced velocity change close to the terminus. Future studies should consider the flow velocity dependence on the distance to the terminus, and local geometry, to distinguish subglacial hydrologic system changes from frontal processes and local basal conditions.

In this paper, we obtain a precise formula for the one-level density of L-functions attached to non-Galois cubic Dedekind zeta functions. We find a secondary term which is unique to this context, in the sense that no lower-order term of this shape has appeared in previously studied families. The presence of this new term allows us to deduce an omega result for cubic field counting functions, under the assumption of the Generalised Riemann Hypothesis. We also investigate the associated L-functions Ratios Conjecture and find that it does not predict this new lower-order term. Taking into account the secondary term in Roberts’s conjecture, we refine the Ratios Conjecture to one which captures this new term. Finally, we show that any improvement in the exponent of the error term of the recent Bhargava–Taniguchi–Thorne cubic field counting estimate would imply that the best possible error term in the refined Ratios Conjecture is $O_\varepsilon (X^{-\frac 13+\varepsilon })$. This is in opposition with all previously studied families in which the expected error in the Ratios Conjecture prediction for the one-level density is $O_\varepsilon (X^{-\frac 12+\varepsilon })$.

Osiurak and Reynaud do not explain the evolutionary emergence and development of the elephant in the room, that is, technical cognition. We first argue that there is a tight correlation between the evolution of cumulative technological culture (CTC) and the evolution of reasoning about abstract forces. Second, intentional teaching plays a greater role in CTC evolution than acknowledged in the target article.

Immigrant children in Denmark differ greatly in educational outcomes. This study examined whether systematic differences in majority language (L2) and preliteracy skills are apparent already at ages 2–6 in immigrant children in Denmark across regional immigration background. Danish language and preliteracy skills in 1,211 immigrant children in four regional groups (based on maternal origin) and 11,259 native Danish nonimmigrant children, all enrolled in Danish childcare centers, were assessed using an age- and gender-normed language assessment instrument. Hierarchical linear models showed that all four immigrant groups scored significantly lower than the native Danish group; the negative coefficients diminished but remained significant when socioeconomic background and having a native Danish father were controlled for. In addition, even with these controls, significant differences existed between some of the immigrant groups, suggesting that factors relating to regional immigrant background were important sources of differences in L2 development. A greater immigrant disadvantage for language than preliteracy skills was found; two immigrant groups did not differ significantly from the nonimmigrant Danish group for preliteracy skills. The results suggest that measures to reduce inequalities in long-term educational achievement between immigrant groups should be taken already before school with a particular focus on L2 language skills.

The Grönhögen-2015 core drilling on southern Öland, Sweden, penetrated 50.15 m of Cambrian Series 3, Furongian and Lower–Middle Ordovician strata. The Cambrian succession includes the Äleklinta Member (upper Stage 5) of the Borgholm Formation and the Alum Shale Formation (Guzhangian–Tremadocian). Agnostoids and trilobites allowed subdivision of the succession into eight biozones, in ascending order: the uppermost Cambrian Series 3 (Guzhangian) Agnostus pisiformis Zone and the Furongian Olenus gibbosus, O. truncatus, Parabolina spinulosa, Sphaerophthalmus? flagellifer, Ctenopyge tumida, C. linnarssoni and Parabolina lobata zones. Conspicuous lithologic unconformities and the biostratigraphy show that the succession is incomplete and that there are several substantial gaps of variable magnitudes. Carbon isotope analyses (δ13Corg) through the Alum Shale Formation revealed two globally significant excursions: the Steptoean Positive Carbon Isotope Excursion (SPICE) in the lower–middle Paibian Stage, and the negative Top of Cambrian Excursion (TOCE), previously referred to as the HERB Event, in Stage 10. The δ13Corg chemostratigraphy is tied directly to the biostratigraphy and used for an improved integration of these excursions with the standard agnostoid and trilobite zonation of Scandinavia. Their relations to that of coeval successions in Baltoscandia and elsewhere are discussed. The maximum amplitudes of the SPICE and TOCE in the Grönhögen succession are comparable to those recorded in drill cores retrieved from Scania, southern Sweden. The results of this study will be useful for assessing biostratigraphic relations between shale successions and carbonate facies on a global scale.

This article discusses the relation between knowing, learning and teaching in relation to early Palaeolithic technologies. We begin by distinguishing between three kinds of knowledge: knowing how, knowing what and knowing that. We discuss the relation between these types of knowledge and different forms of learning and long-term memory systems. On the basis of this analysis, we present three types of teaching: (1) helping and correcting; (2) showing; and (3) explaining. We then use this theoretical framework to suggest what kinds of teaching are required for the pre-Oldowan, the Oldowan, the early Acheulean and the late Acheulean stone-knapping technologies. As a general introductory overview to this special section, the text concludes with a brief presentation of the papers included.

We argue that Kline's analysis does not account for the evolutionary mechanisms that can explain the uniqueness of human teaching. We suggest that data should be complemented by an analysis of archaeological material with respect to what forms of teaching are required for the transmission of technologies over generations.

The Next Generation Transit Survey (NGTS) is a new ground-based survey for transiting exoplanets. Our primary goal is to find the first statistically-significant sample of Neptunes and super-Earths that are bright enough for radial velocity confirmation. By measuring precise masses and radii we will constrain the bulk composition and internal structure of planets that span the transition between the gas giants and terrestrial planets. Our brightest exoplanets will also be suitable for atmospheric characterisation with large facilities such as the VLT, JWST and the E-ELT. NGTS construction began in June 2013, and the survey is due to commence in 2014.

Angle of arrival (AOA), time of arrival (TOA), and frequency of arrival (FOA) can be measured for a signal from multiple platforms. By combining such measurements it is possible to obtain high-accuracy emitter position estimates. This requires a data link with low latency and sufficient data-rate, and synchronization of the platforms in space, time, and search pattern. Typically several of the platforms will have to make their measurements in the radar sidelobes that require very high receiver sensitivity. This paper focuses on discussing how the sensitivity can be improved using antenna gain or signal processing.