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Calanoid copepods of the genus Calanus represent an important, nutrient-rich food source for a multitude of Arctic marine organisms. Although morphologically very similar, their life histories and ecological roles differ. Because the distribution of Calanus glacialis and C. finmarchicus corresponds to Arctic and Atlantic water masses, respectively, they are regularly used as climate indicators. A correct identification of these species is therefore necessary in many ecological, environmental and climatological studies. In this study, we aimed at validating the traditionally used morphological characteristics (combining prosome length and copepodite stage) for separation of species of Calanus by using molecular tools (PCR–RFLP of the 16S mtDNA). A total of 418 specimens of copepodite stages CIV, CV and CVI(af) from three Arctic fjords have been identified both morphologically and genetically. We find that the morphological identification systematically overestimates the abundance of C. finmarchicus at the expense of C. glacialis. Hence, parts of the C. glacialis populations are found to be structurally smaller and the within population size range thus larger than previously assumed. Consequently, using the traditional morphological species delimitation poses a serious problem in the use of these two species as indicators of Atlantic versus Arctic water masses and thus as climatic indicators. Furthermore, it obscures our understanding of the life history differences between the two species and of their relative importance as food for a number of ecologically and economically important species in the Arctic.

Crack propagation in brittle rock was simulated under different conditions to describe fracturing behavior of rocks due to the applied stress e.g., water pressure. It is assumed that pre-existing cracks initiate and propagate from the edges of the borehole. The two-dimensional finite element fracture code Franc2D with the non-cohesive method was used for computing the stress intensity factor (SIF), energy-release rates (G), and crack propagation and fracturing time. Static tensile and normal-distributed stresses were used within Franc2D to describe the fracture creation and propagation. Therefore, the pressure inside the bore hole was distributed as a tensile load along with the crack faces. Different scenarios were simulated by changing the boundary conditions, crack initiation, and propagation paths. The SIF determines the amount of tensile failure that is required to create a fracture. Then, the injection rate and pressure can be determined. The direction of fracturing is perpendicular to the maximum applied stresses. The crack propagation direction was compared with experimental observations taken from the literature. The predefined SIF solutions were modified according to the Franc2D solutions. Hence, the ability to use Franc2D for fracture simulation in brittle rock was demonstrated.

High-efficacy therapies in multiple sclerosis are traditionally used after unsuccessful treatment with first-line disease modifying therapies. We hypothesised that early commencement of high-efficacy therapy would be associated with reduced long-term disability. We therefore aimed to compare long-term disability outcomes between patients who started high-efficacy therapies within 2 years of disease onset with those who started 4–6 years after disease onset. In this retrospective international observational study, we obtained data from the MSBase registry and the Swedish MS registry, which prospectively collect patient data that are specific to multiple sclerosis as part of routine clinical care. We identified adult patients (aged ≥18 years) with relapsing-remitting multiple sclerosis, with at least 6 years of follow-up since disease onset, and who started the high-efficacy therapy (rituximab, ocrelizumab, mitoxantrone, alemtuzumab, or natalizumab) either 0–2 years (early) or 4–6 years (late) after clinical disease onset. We matched patients in the early and late groups using propensity scores calculated on the basis of their baseline clinical and demographic data. The primary outcome was disability, measured with the Expanded Disability Status Score (EDSS; an ordinal scale of 0–10, with higher scores indicating increased disability), at 6–10 years after disease onset, assessed with a linear mixed-effects model. We identified 6149 patients in the MSBase registry who had been given high-efficacy therapy, with data collected between Jan 1, 1975, and April 13, 2017, and 2626 patients in the Swedish MS Registry, with data collected between Dec 10, 1997, and Sept 16, 2019. Of whom, 308 in the MSBase registry and 236 in the Swedish MS registry were eligible for inclusion. 277 (51%) of 544 patients commenced therapy early and 267 (49%) commenced therapy late. For the primary analysis, we matched 213 patients in the early treatment group with 253 in the late treatment group. At baseline, the mean EDSS score was 2·2 (SD 1·2) in the early group and 2·1 (SD 1·2) in the late group. Median follow-up time for matched patients was 7·8 years (IQR 6·7–8·9). In the sixth year after disease onset, the mean EDSS score was 2·2 (SD 1·6) in the early group compared with 2·9 (SD 1·8) in the late group (p<0·0001). This difference persisted throughout each year of follow-up until the tenth year after disease onset (mean EDSS score 2·3 [SD 1·8] vs 3·5 [SD 2·1]; p<0·0001), with a difference between groups of −0·98 (95% CI −1·51 to −0·45; p<0·0001, adjusted for proportion of time on any disease-modifying therapy) across the 6–10 year follow-up period. High-efficacy therapy commenced within 2 years of disease onset is associated with less disability after 6–10 years than when commenced later in the disease course. This finding can inform decisions regarding optimal sequence and timing of multiple sclerosis therapy. National Health and Medical Research Council Australia and MS Society UK.

The combination of the latest geophysical instruments and geochemical methods applied to the arc volcanism (Aeolian Islands, Italy) has given new insights on the role of active tectonics on fluids migration. A continuous monitoring of the hydrothermal system off the island of Panarea has shown contemporaneous modifications of the vented fluids and the seismic activity of the nearby Stromboli volcano. The almost contemporary start of the last volcanic crisis at Panarea and Stromboli in 2002, besides the contemporary variation of the 3He/4He ratios at both the islands and the large number of submarine crater‐shaped structures at Panarea, bears testimony to interconnections between the volcanic edifices. To confirm a tectonic drive of magmatic fluids over volcanic arcs implies that episodes of volcanic unrest can be triggered by the tectonic activity increasing the volcanic risk for the whole area, and this might be the case of the Stromboli‐Panarea volcanic complex.

Groundwater samples from 33 locations within the Coastal Plain Sands aquifer of Calabar (Nigeria) were collected and analysed for 43 trace elements by means of ICP-MS. The aim of this study is to determine the natural background levels of trace elements as a guide for future pollution monitoring of the aquifer. Secondly, this article focuses on the pollution vulnerability of the coastal plain sand aquifer. Statistical methods have been used to determine the source(s) of these elements. Results show that the area is characterised by four types of groundwater, including: Na-HCO^sub 3^, Na-HCO^sub 3^-Cl, Na-Cl and Ca-Na-HCO^sub 3^-Cl. Secondly, all the elements considered are below normal averages. In addition, the Spearman correlation shows significant correlation especially among the lanthanide group of elements (p<0.0001). Factors analyses indicate mainly two groups of elements. The first group being due to the natural geochemical process (weathering/leaching of the basement lithology; characteristics of the elements) and the second is due to tidal flushing of the estuary. This indicates that the source of the trace element in the aquifer is due to a geogenic process and not anthropogenic. Thus, the present data set will serve as a reference source for pollution monitoring in the area.[PUBLICATION ABSTRACT]

Mosul Dam Lake is one of the largest artificial water reservoirs in Iraq, located in the north of the country. This lake is the main source of drinking water in Iraq, providing water to Mosul, Baghdad, and other cities. The surface area of the lake is 385 km2 at the maximum operation level with a total storage volume of 11.13×109 m3. The climate of the study area is arid to semi arid, with rainfall not exceeding 300 mm/year. The highest temperature in summer reaches more than 55ºC. The lake is monomictic with overturn occurring in the autumn. The difference between the lake surface and bottom temperatures during the summer is more than 17°C (31 14°C) and 2°C during winter (12 10°C). Secchi disk measurements show that Mosul Dam Lake is mesotrophic; only the outlet of Dohuk River is eutrophic. In the current study, the standard plate count agar procedure was used for analyzing 45 samples for heterotrophic bacteria. These samples have been collected from different depths and locations in the study area during two sampling campaigns in February 2011 and July 2011. Water quality parameters (pH, EC, NO3, NO2, PO4, TIC, and DOC) for the same locations and depths of the sampled bacteria were measured. Results of heterotrophic bacteria analysis show that Mosul Dam Lake is contaminated with bacteria. The river Dohuk is the major source of this pollution. Occurrence of heterotrophic bacteria during the summer exceeds the winter values by 57%. In a layer located 12–15 m below the surface of the lake with a temperature of 10.9°C, a linear correlation between heterotrophic bacteria and water quality parameters (R2 >0.7) in winter could be observed. However, with respect to phosphorous, a logarithmic relationship with heterotrophic bacteria can be seen. In the summer season, the heterotrophic bacteria had a clear relation with most water quality parameters (R2 >0.7) at depths of between 40 and 60 m within the

Monitoring of surface water and shallow aquifers inside and outside of the Los Azufres geothermal fieldduring the period November 1994 to May 1996 led to thedetection of some contamination of surface water andshallow aquifers due to exploitation of the deepbrines. Leaking of evaporation ponds and pipelines,occasionally overflowing of reinjection wells and pondrims as well as outflowing of brines duringrehabilitation or drilling operations, are potentialcontamination sources within the cycle of geothermalproduction.Temporarily and/or permanently increased traceelements concentrations, especially Fe, Mn, F, B, andAs in surface waters within the geothermal field aswell as up to 10 km outside, were observed. Maximumvalues of 125 and 8 mg L super(-1) were observed for B and As,respectively. The discharge of hypersaline geothermalbrines also causes salinization of surrounding soils.It occasionally happens that cattle drink from thebrines. The use of the river for irrigation anddrinking water supply in the surrounding regions maycause accumulation of toxic elements in the human foodchain or may endanger the public health.The establishment of a closed geothermal productioncycle can be achieved by simple remediationtechniques, such as sealing of the pond walls, removalof overflow channels, direct reinjection without anyreposal time in evaporation ponds, as well as animproved security and control system.

The computer program PHREEQC was used to determined the distribution, chemical speciation and mineral saturation indices in a fresh groundwater environment with limited mining activities in the adjoining areas. The aim was mainly to determine the potential risk of a coastal plain aquifer contamination by some potentially toxic elements. The results show that the elements Ba, Cd, Cu, Fe, Mn, Ni, Rb, Sr, and Zn are distributed as free metal ions. Arsenic is in the neutral form of H^sub 3^AsO^sub 3^^sup o^, while three species of aluminium [Al^sup 3+^, AlOH^sub 2^, Al(OH)^sub 2^ ^sup +^] dominate. The major species of uranium include UO^sub 2^CO^sub 3^, UO^sub 2^^sup 2+^+, UO^sub 2^^sup +^, and UO^sub 2^OH^sup +^,^sup ^respectively, in order of abundance. The groundwater is saturated with respect to alunite [KAl^sub 3^ (SO^sub 4^)^sub 2^ (OH)^sub 6^], basaluminite [Al^sub 4^ (OH)^sub 10^ SO^sub 4^], boehmite [Al(OH)], Cu metal (Cu), cuprous ferrite (CuFeO^sub 2^), diaspore [AlO(OH)], gibbsite [Al(OH)^sub 3^], goethite (FeOOH), hematite (Fe^sub 2^O^sub 3^), magnetite (Fe^sub 3^O^sub 4^) and uraninite (UO^sub 2^). Most of the species are not mobile under the prevailing pH (3.3 to 5.9) and Eh (7 to 158 mV) conditions. The mobile ones are very low in concentration and will be immobilized by precipitation of mineral phases. The study concludes that presently these species do not pose any risk to the aquifer.[PUBLICATION ABSTRACT]

Tracking data of marine predators are increasingly used in marine spatial management. We developed a spatial dataset with estimates of the monthly distribution of six pelagic seabird species breeding in the Northeast Atlantic. The dataset is based on year-round global location sensor (GLS) tracking data of 2356 adult seabirds from 2006-2019 from a network of seabird colonies, data describing the physical environment, and data on seabird population sizes. Tracking and environmental data were combined in monthly species distribution models (SDMs). Cross-validations were used to assess the transferability of models between years and breeding locations. The analyses showed that birds from colonies close to each other (<500 km apart) used the same nonbreeding habitats, while birds from distant colonies (>1000 km) used colony-specific, and in many cases, non-overlapping habitats. Based on these results, the SDM from the nearest model colony was used to predict the distribution of all seabird colonies lying within a species-specific cut-off distance (400-500 km). The uncertainties in predictions were estimated by cluster bootstrap sampling. The resulting dataset consists of 4692 map layers, each layer predicting the densities of birds from a given species, colony and month across the North Atlantic. The dataset represents the annual distribution of 23.5 million adult pelagic seabirds, or 87% of the Northeast Atlantic breeding population of the study species. We show how the dataset can be used in population and spatial management applications, including the detection of population-specific nonbreeding habitats and identifying populations influenced by marine protected areas.

Despite being the main drinking water resource for over 5 million people, the water balance of the Eastern Mountain Aquifer system on the western side of the Dead Sea is poorly understood. The regional aquifer consists of fractured and karstified limestone – aquifers of Cretaceous age, and it can be separated into a Cenomanian aquifer (upper aquifer) and Albian aquifer (lower aquifer). Both aquifers are exposed along the mountain ridge around Jerusalem, which is the main recharge area. From here, the recharged groundwater flows in a highly karstified aquifer system towards the east and discharges in springs in the lower Jordan Valley and Dead Sea region. We investigated the Eastern Mountain Aquifer system for groundwater flow, groundwater age and potential mixtures, and groundwater recharge. We combined 36Cl ∕ Cl, tritium, and the anthropogenic gases SF6, CFC-12 (chlorofluorocarbon) and CFC-11, while using CFC-113 as “dating” tracers to estimate the young water components inside the Eastern Mountain Aquifer system. By application of lumped parameter models, we verified young groundwater components from the last 10 to 30 years and an admixture of a groundwater component older than about 70 years. Concentrations of nitrate, simazine (pesticide), acesulfame K (ACE-K; artificial sweetener) and naproxen (NAP; drug) in the groundwater were further indications of infiltration during the last 30 years. The combination of multiple environmental tracers and lumped parameter modelling helped to understand the groundwater age distribution and to estimate recharge despite scarce data in this very complex hydrogeological setting. Our groundwater recharge rates support groundwater management of this politically difficult area and can be used to inform and calibrate ongoing groundwater flow models.