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Abstract. The last glacial period (LGP; ca. 110–10 kyr BP) was marked by the existence of two types of abrupt climatic changes, Dansgaard–Oeschger (DO) and Heinrich (H) events. Although the mechanisms behind these are not fully understood, it is generally accepted that the presence of ice sheets played an important role in their occurrence. While an important effort has been made to investigate the dynamics and evolution of the Laurentide ice sheet (LIS) during this period, the Eurasian ice sheet (EIS) has not received much attention, in particular from a modeling perspective. However, meltwater discharge from this and other ice sheets surrounding the Nordic seas is often implied as a potential cause of ocean instabilities that lead to glacial abrupt climate changes. Thus, a better comprehension of the evolution of the EIS during the LGP is important to understand its role in glacial abrupt climate changes. Here we investigate the response of the EIS to millennial-scale climate variability during the LGP. We use a hybrid, three-dimensional, thermomechanical ice-sheet model that includes ice shelves and ice streams. The model is forced off-line via a novel perturbative approach that, as opposed to conventional methods, clearly differentiates between the spatial patterns of millennial-scale and orbital-scale climate variability. Thus, it provides a more realistic treatment of the forcing at millennial timescales. The effect of both atmospheric and oceanic variations are included. Our results show that the EIS responds with enhanced ice discharge in phase with interstadial warming in the North Atlantic when forced with surface ocean temperatures. Conversely, when subsurface ocean temperatures are used, enhanced ice discharge occurs both during stadials and at the beginning of the interstadials. Separating the atmospheric and oceanic effects demonstrates the major role of the ocean in controlling the dynamics of the EIS on millennial timescales. While the atmospheric forcing alone is only able to produce modest iceberg discharges, warming of the ocean leads to higher rates of iceberg discharges as a result of relatively strong basal melting at the margins of the ice sheet. Our results clearly show the capability of the EIS to react to glacial abrupt climate changes, and highlight the need for stronger constraints on the ice sheet's glacial dynamics and climate–ocean interactions.

Materials processing by ultrafast lasers offers several distinct possibilities for micro/nano scale applications. This is due to the unique characteristics of the laser-matter interactions involved, when sub-picosecond pulses are employed. Prospects arising will be discussed in the context of surface and in bulk laser induced modifications. In particular, examples of diverse applications including the development and functionalization of laser engineered surfaces, the laser transfer of biomolecules and the functionalization of 3D structures constructed by three-photon stereolithography will be presented. Furthermore, the removal of molecular substrates by ultrafast laser ablation will be discussed with emphasis placed on assessing the photochemical changes induced in the remaining bulk material. The results indicate that in femtosecond laser processing of organic materials, besides the well acknowledged morphological advantages, a second fundamental factor responsible for its success pertains to the selective chemical effects. This is crucial for the laser cleaning of sensitive painted artworks.

to refer to a dynamic socio-analytic framework that relies on learning processes as the main source of the emergence, persistence and change of institutional arrangements (cultural norms and legal rules). For the authors, institutions frame and guide the mental models, decisions and behaviors of social actors over time. What is more, the cognitive foundations of these processes may explain their success or failure.Back in 2001, Mantzavinos had already written an outstanding book –

Abstract. The recovery phase of an earthquake-affected settlement is a time-consuming and complex process that requires monitoring, which is now possible using UAS. The purpose of this paper is to present the methodology followed and the results obtained by the exploitation of UAS for rapid multitemporal 3D mapping during the recovery phase of Vrisa traditional settlement, Lesvos island, Greece, which was highly damaged by the earthquake (Mw=6.3) on 12th June 2017. More analytically, three (3) flight campaigns covering the period July 2017 – May 2020 took place by means of an UAS for collecting high-resolution images on: i) 19th May 2019, ii) 29th September 2019, iii) 17th May 2020. Structure from Motion (SfM) and Multi Stereo View (MSV) methods have been applied and produced: i) Digital Surface Models – DSMs, ii) 3D Point Clouds – 3DPC and iii) Orthophoto-maps, of Vrisa. In parallel, GIS capabilities has been exploit to calculate building volumes based on: a) DSM produced by UAS image processing, b) DEM produced by 233 RTK measurements and c) building footprints derived by the digitization of the orthophoto-map of 25th July 2017. The methodology developed and implemented achieves extremely reliable results in a relatively easy, fast and economically feasible way, which is confirmed with great precision by field work. By applying the above-described methodology, it was possible to monitoring the recovery phase during July 2017 and May 2020 which 302/340 buildings that had been severely damaged by the earthquake have been demolished. A small number of new buildings have also been rebuilded and small number of buildings that have just begun excavations for their construction. An important parameter for obtaining reliable data and comparable results is the correct selection of flight parameters and their maintenance at all times when it is decided to take data, without affecting the accuracy of the results from taking photos or videos. Automation in the future of the proposed methodology can significantly accelerate the achievement of reliable results without the intermediate interpretation of orthophoto-maps.

This article examines the politics of smell at the edge of perception. In January 2014, the municipal water supply of Charleston, West Virginia was contaminated by an under-characterized chemical, crude MCHM. Even when instrumental measurements no longer detected the chemical, people continued to smell its licorice-like odor. In a space where nothing was certain, smell became the only indicator of potential harm. Officials responded by commissioning state-funded sensory testing of crude MCHM to determine its sensory threshold. Via the critical passage point of sensory science, some instances of embodied attunement were allowed to enter into the evidentiary regimes of perception, while other, similarly trained moments of attunement were excluded from the process. This, I show, produced knowledge about the spilled chemical that maintained the systems that contributed to the spill in the first place. Drawing on new materialist thought, I riff on biology and ‘transduce’ the ephemeral phenomena of smelling crude MCHM into a new medium: Rather than thinking of smell as a volatile molecular material (an odorant), I show that consideration of smell as a manipulable object that one can imagine as having tangible substance and shape offers a way to experiment with disciplinary forms. I suggest an alternate future, where sensory science acts to record sensory labor that produces facts about collective experience that cannot (easily) travel through current systems, a process that is one possible way of beginning to unravel entrenched systems of toxic harm.

Science changes in waves, the so-called paradigm shifts or scientific revolutions. This concept was prominently elabo­rated by Thomas S. Kuhn more than 50 years ago in what remains one of the most cited science philosophy books of all time. Kuhn described how “normal science” experiences anomalies, which bring it to crisis and revolution from which a new, immature scientific paradigm results, which over time becomes the new normal. Building on an analysis on how this applies to toxicology and its change in approach in 2008, we concluded at the time that toxicology had encountered a number of such anomalies and was moving into crisis. Here, the progress along Kuhn’s trajectory over the last 12 years of a scientific revolution is discussed. We conclude that this decade has shown up even more anomalies, and the perception of crisis has spread and consolidated. Indications of revolutionary paradigm changes are emerging. published

Microcalcifications are the main indicator for breast cancer. Dual energy imaging can enhance the detectability of calcifications by suppressing the tissue background. Two digital images are obtained using two different spectra, for the low- and high-energy respectively, and a weighted subtracted image is produced. In this study, a dual energy method for the detection of the minimum breast microcalcification thickness was developed. The used integrated prototype system consisted of a modified tungsten anode X-ray tube combined with a high resolution CMOS sensor. The breast equivalent phantom used was an elastically compressible gel of polyvinyl alcohol (PVAL). Hydroxyapatite was used to simulate microcalcifications with thicknesses ranging from 50 to 500 μm. The custom made phantom was irradiated with 40kVp and 70kVp. Tungsten (W) anode spectra filtered with 100μm Cadmium and 1000pm Copper, for the low- and high-energy, respectively. Microcalcifications with thicknesses 300μm or higher can be detected with mean glandular dose (MGD) of 1.62mGy.

International audience; We present experimental photoelectron spectra obtained by ionizing two-valence electron Sr atoms with ≈25 fs Ti- Sapphire laser pulses and we show preliminary evidence that electron-electron correlation effects dominate for laser intensities 13 W-cm-2, while a single electron picture prevails when the laser intensity is increased further.