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The first of the so-called diffraction-limited storage rings (DLSRs), MAX I V, has now gone into operation. For this ring, a multibend achromat (MBA) lattice is employed in order to achieve a small electron beam emittance. Several non-conventional technical system solutions have been introduced in order to reduce size, cost, assembly time, installation effort and to increase the ring robustness. Examples of this are solid magnet blocks housing several magnet items, a fully NEG-coated vacuum system and a low frequency RF system. The commissioning started in late August 2015. Several base-line parameters have now been reached like a sufficiently high stored circulating current, beam lifetime and beam quality for beamline commissioning. The MBA concept and the operation of the non-conventional solutions technical systems are verified. This article describes some of the technical solutions chosen and the early commissioning results.

The NeoArabia project tries to understand how environmental, social, economic and technological factors work in concert to influence settlement and abandonment along a latitudinal transect of 1200 km from UAE to southern Oman. This region was affected by wide north–south variations in the Indo‐Arabian monsoon, marine upwelling activity and eustatic variations in the Mid‐Holocene. On the local settlement scale, this transect is based on fine stratigraphic excavations and permits the reconstruction of the site formation processes and site catchment analysis. A large number of studies have been conducted on the Ruways‐1 site, focusing on a deep stratified sequence corresponding to three millennia of occupation. These studies include on‐site climate‐environmental signal analysis, local palaeogeography and environmental reconstruction, reservoir effect studies, typo‐technological studies, palaeoeconomic strategies, anthropological studies, sclerochronological studies and, finally, site formation processes, the understanding of which makes it possible to explain the potential and limits of the archaeological excavation. The first results confirm the richness of these archaeological archives for documenting the socio‐environmental dynamics, but also the richness of its complex sedimentary structure and the importance of conducting fine and multidisciplinary excavations to answer questions about the rhythms and functions of occupations and the causalities of socio‐environmental changes. [ABSTRACT FROM AUTHOR]

The monitoring of the N'Kossa offshore oil and gas fields in the Republic of Congo allowed us to assess the ecological traits of two polychaete species belonging to Sigambra (Annelida, Pilargidae). Sigambra parva occur in very low densities in all bottoms, except the most impacted, where it is totally absent; it is an undescribed species that reached >4,000 ind/m 2 in hydrocarbon-enriched sediments. Their distribution patterns are compared with those of other polychaetes, showing a range of affinities for hydrocarbon-enriched sediments in the N'Kossa region. Our results suggest that S. parva would be a representative of the original local fauna, while the species associated with artificial hydrocarbon-enriched sediments, including the other Sigambra , six more polychaetes and a bivalve, could be natively associated with natural hydrocarbon-enriched sediments, using the former as alternative habitats and as dispersal stepping stones. This ecological segregation, together with a careful morphological and morphometric analyses led us to describe the latter as a new species, namely Sigambra nkossa sp. nov. Moreover, morphometric analysis allowed us to discuss on the taxonomic robustness of the key morphological characters of S. nkossa sp. nov., as well as to emend the generic diagnosis of Sigambra to accommodate the new species., Competing Interests: Sébastien Thorin, Romain Le Gall & Éric Dutrieux are employed by CREOCEAN. Claude-Henri Chaineau is employed by TotalEnergies., (©2022 Martin et al.)

In this paper the design of the free-electron laser (FEL) in the SXL (Soft X-ray Laser) project at the MAX IV Laboratory is presented. The target performance parameters originate in a science case put forward by Swedish users and the SXL FEL is foreseen to be driven by the existing MAX IV 3 GeV linac. The SXL project is planned to be realized in different stages and in this paper the focus is on Phase 1, where the basic operation mode for the FEL will be SASE (self-amplified spontaneous emission), with an emphasis on short pulses. Simulation results for two linac bunches (high and low charge) with different pulse duration are illustrated, as well as the performance for two-color/two-pulses mode and power enhancement through tapering. Besides standard SASE and optical klystron configurations, the FEL setup is also tailored to allow for advanced seeding schemes operations. Finally possible upgrades that will be implemented in a second phase of the project are discussed., (open access.)

The Gulf of Lions (GoL) is among the most productive areas of the Mediterranean Sea, with the Rhône River contributing with as much as 90% of the liquid and solid materials (including anthropogenic chemicals) reaching the area. In this paper, we assessed whether classical descriptive ecology and MaxEnt predictive species distribution modelling were able to provide complementary information when analysing the long-distance influence of the river discharges on the GoL benthic ecosystem. Samples were collected in August 2014 from 12 stations covering the sedimentary plain of the deep submarine delta, from the Gulf of Fos to Gruissan. Sediments were mostly muddy with a high organic carbon and low P and N contents first decreasing and then increasing from east to west. The same pattern occurred for chlorophyll-a, particulate organic carbon and sea surface temperature, and was overall correlated with metal and pollutant contents derived from agricultural, port, urban and industrial sources driven by Rhône outputs. We observed a typical deltaic succession in the benthos, showing a relatively low diversity and including polychaetes (Sternaspis scutata) and holothurians (Oestergrenia digitata) known to be indicators of high sedimentation rates. Overall, benthos showed an inversed pattern regarding environmental variables, an evident consequence of the Rhône River influence. The suitability of some species was either positively or negatively correlated with some of the environmental variables, producing species-specific predicted distribution patterns, with the highest amount of information allowing to predict distributions being mainly provided by organic pollutants. Even with a limited number of available samples, our integrated approach reveals to be a very robust tool to highlight hidden patterns and contributes to improve our knowledge on how river-mediated anthropogenic discharges may influence biodiversity distribution and functional patterns in marine benthic ecosystems., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The MAX IV 3 GeV electron storage ring in Lund, Sweden, is the first of a new generation of light sources to make use of the multibend-achromat lattice (MBA) to achieve ultralow emitance and hence ultrahigh brightness and transverse coherence. The conceptual basis of the MAX IV 3 GeV ring project combines a robust lattice design with a number of innovative engineering choices: compact, multifunctional magnet blocks, narrow low-conductance NEG-coated copper vacuum chambers and a 100 MHz radio-frequency system with passively operated third-harmonic cavities for bunch lengthening. In this paper, commissioning and first-year operational results of the MAX IV 3 GeV ring are presented, highlighting those aspects that are believed to be most relevant for future MBA-based storage rings. The commissioning experience of the MAX IV 3 GeV ring offers in this way an opportunity for validation of concepts that are likely to be essential ingredients of future diffraction-limited light sources., (open access.)

The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100 fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.

Although the limitations of implementing the mitigation hierarchy have been widely discussed in scientific literature, these studies have drawn mainly on feedback concerning terrestrial ecosystems. In the case of development projects in marine and coastal environments, certain issues must be tackled to improve existing practice. This article focuses on the methodologies used to assess both the ecological losses resulting from a development project and the ecological gains generated by an offset measure. The originality of this article is to propose a standardized, operational approach regardless of the development project and the ecosystem impacted that (i) enhances avoidance and reduction efforts and (ii) assesses biodiversity offset needs based on data available in Environmental Impact Assessments (EIAs). The proposed hybrid method combines a multi-criteria analysis of the state of the environment, inspired by the Unified Mitigation Assessment Method (UMAM), and a more accurate assessment at indicator level inspired by Habitat Equivalency Analysis (HEA). The steps of the method, from the selection of biophysical indicators to offset sizing, are described and are then applied to two EIA case studies: one related to a port extension and the other to an offshore wind farm., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The ecological quality of the Gulf of Lions coast was assessed using three biotic indices (H', AMBI and BQI). The three indices correlated positively. The positive correlation between AMBI and BQI was surprising and was mostly due to the fact that the dominant species Ditrupa arietina featured a low ES50(0.05) but was classified in GI by AMBI. Both H' and BQI were efficient in distinguishing impacted from un-impacted sites but AMBI was not. Differences between H' and BQI were mainly due to the scale used to translate indices in terms of EcoQ. The three indices were able to detect the major changes in macrofauna composition, which occurred in the Bay of Banyuls-sur-Mer during the last 40years. However, the interpretations of such changes in terms of EcoQ differed between indices. These results are discussed relative to the characteristics of the tested indices.