| 1. |
|
|
| 2. |
- Golub, Malgorzata, et al.
(författare)
-
A framework for ensemble modelling of climate change impacts on lakes worldwide : the ISIMIP Lake Sector
- 2022
-
Ingår i: Geoscientific Model Development. - : Copernicus Publications. - 1991-959X .- 1991-9603. ; 15:11, s. 4597-4623
-
Tidskriftsartikel (refereegranskat)abstract
- Empirical evidence demonstrates that lakes and reservoirs are warming across the globe. Consequently, there is an increased need to project future changes in lake thermal structure and resulting changes in lake biogeochemistry in order to plan for the likely impacts. Previous studies of the impacts of climate change on lakes have often relied on a single model forced with limited scenario-driven projections of future climate for a relatively small number of lakes. As a result, our understanding of the effects of climate change on lakes is fragmentary, based on scattered studies using different data sources and modelling protocols, and mainly focused on individual lakes or lake regions. This has precluded identification of the main impacts of climate change on lakes at global and regional scales and has likely contributed to the lack of lake water quality considerations in policy-relevant documents, such as the Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC). Here, we describe a simulation protocol developed by the Lake Sector of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) for simulating climate change impacts on lakes using an ensemble of lake models and climate change scenarios for ISIMIP phases 2 and 3. The protocol prescribes lake simulations driven by climate forcing from gridded observations and different Earth system models under various representative greenhouse gas concentration pathways (RCPs), all consistently bias-corrected on a 0.5 degrees x 0.5 degrees global grid. In ISIMIP phase 2, 11 lake models were forced with these data to project the thermal structure of 62 well-studied lakes where data were available for calibration under historical conditions, and using uncalibrated models for 17 500 lakes defined for all global grid cells containing lakes. In ISIMIP phase 3, this approach was expanded to consider more lakes, more models, and more processes. The ISIMIP Lake Sector is the largest international effort to project future water temperature, thermal structure, and ice phenology of lakes at local and global scales and paves the way for future simulations of the impacts of climate change on water quality and biogeochemistry in lakes.
|
|
| 3. |
- Hirao, Yuki, et al.
(författare)
-
OGLE-2017-BLG-0406 : Spitzer Microlens Parallax Reveals Saturn-mass Planet Orbiting M-dwarf Host in the Inner Galactic Disk
- 2020
-
Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 160:2
-
Tidskriftsartikel (refereegranskat)abstract
- We report the discovery and analysis of the planetary microlensing event OGLE-2017-BLG-0406, which was observed both from the ground and by the Spitzer satellite in a solar orbit. At high magnification, the anomaly in the light curve was densely observed by ground-based-survey and follow-up groups, and it was found to be explained by a planetary lens with a planet/host mass ratio of q = 7.0 x 10(-4) from the light-curve modeling. The ground-only and Spitzer-only data each provide very strong one-dimensional (1D) constraints on the 2D microlens parallax vector pi(E). When combined, these yield a precise measurement of pi(E) and of the masses of the host M-host = 0.56 +/- 0.07 M-circle dot and planet M-planet = 0.41 +/- 0.05 M-Jup. The system lies at a distance D-L = 5.2 +/- 0.5 kpc from the Sun toward the Galactic bulge, and the host is more likely to be a disk population star according to the kinematics of the lens. The projected separation of the planet from the host is a(perpendicular to) = 3.5 +/- 0.3 au (i.e., just over twice the snow line). The Galactic-disk kinematics are established in part from a precise measurement of the source proper motion based on OGLE-IV data. By contrast, the Gaia proper-motion measurement of the source suffers from a catastrophic 10 sigma error.
|
|
| 4. |
- Khaliha, Sara, et al.
(författare)
-
Defective graphene nanosheets for drinking water purification : Adsorption mechanism, performance, and recovery
- 2021
-
Ingår i: FlatChem. - : Elsevier. - 2452-2627. ; 29
-
Tidskriftsartikel (refereegranskat)abstract
- Defect-rich graphene oxide (dGO) was used as sorbent for organic contaminants of emerging concern in tap water, including drugs and dyes, and the performance compared to those of lower-defects graphene types. The role of holes and carbonyl- carboxylic groups on graphene nanosheets surface on the adsorption mechanism and efficiency was investigated. dGO showed enhanced adsorption capacity toward two fluoroquinolone antibiotics (ofloxacin, OFLOX, and ciprofloxacin, CIPRO) in tap water with a maximum capacity of 650 mg/g, compared to 204 mg/g for Hummers derived commercial GO (hGO) and 125 mg/g for less defected Brodie derived GO (bGO) for OFLOX. The role of defects on the selective adsorption of OFLOX was also modelled by MD simulations, highlighting a mechanism mainly driven by the shape complementarity between the graphene holes and the molecules. Adsorption isotherms revealed different adsorption model for dGO, with a Langmuir fitting for dGO and BET fitting for all the other investigated samples. The maximum adsorption capacity of dGO for OFLOX was about six times higher than that of Granular Activated Carbon (95 mg/g), the industrial adsorption standard technology. Finally, it was also demonstrated that dGO can be recovered from treated water by ultrafiltration, this preventing secondary contamination risks and enabling safe use of graphene nanosheets for water purification.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Najafi, Leyla, et al.
(författare)
-
Topochemical Transformation of Two-Dimensional VSe2 into Metallic Nonlayered VO2 for Water Splitting Reactions in Acidic and Alkaline Media
- 2022
-
Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 16:1, s. 351-367
-
Tidskriftsartikel (refereegranskat)abstract
- The engineering of the structural and morphological properties of nanomaterials is a fundamental aspect to attain desired performance in energy storage/conversion systems and multifunctional composites. We report the synthesis of room temperature-stable metallic rutile VO2 (VO2 (R)) nanosheets by topochemically transforming liquid-phase exfoliated VSe2 in a reductive Ar-H2 atmosphere. The asproduced VO2 (R) represents an example of two-dimensional (2D) nonlayered materials, whose bulk counterparts do not have a layered structure composed by layers held together by van der Waals force or electrostatic forces between charged layers and counterbalancing ions amid them. By pretreating the VSe2 nanosheets by O-2 plasma, the resulting 2D VO2 (R) nanosheets exhibit a porous morphology that increases the material specific surface area while introducing defective sites. The assynthesized porous (holey)-VO2 (R) nanosheets are investigated as metallic catalysts for the water splitting reactions in both acidic and alkaline media, reaching a maximum mass activity of 972.3 A g(-1) at -0.300 V vs RHE for the hydrogen evolution reaction (HER) in 0.5 M H2SO4 (faradaic efficiency = 100%, overpotential for the HER at 10 mA cm(-2) = 0.184 V) and a mass activity (calculated for a non 100% faradaic efficiency) of 745.9 A g(-1) at +1.580 V vs RHE for the oxygen evolution reaction (OER) in 1 M KOH (overpotential for the OER at 10 mA cm(-2) = 0.209 V). By demonstrating proof-of-concept electrolyzers, our results show the possibility to synthesize special material phases through topochemical conversion of 2D materials for advanced energy-related applications.
|
|
| 8. |
- Najafi, Leyla, et al.
(författare)
-
Transition metal dichalcogenides as catalysts for the hydrogen evolution reaction : The emblematic case of "inert" ZrSe2 as catalyst for electrolyzers
- 2022
-
Ingår i: Nano Select. - : Wiley-VCH Verlagsgesellschaft. - 2688-4011. ; 3:6, s. 1069-1081
-
Tidskriftsartikel (refereegranskat)abstract
- The development of earth-abundant electrocatalysts (ECs) operating at high current densities in water splitting electrolyzers is pivotal for the widespread use of the current green hydrogen production plants. Transition metal dichalcogenides (TMDs) have emerged as promising alternatives to the most efficient noble metal ECs, leading to a wealth of research. Some strategies based on material nanostructuring and hybridization, introduction of defects and chemical/physical modifications appeared as universal approaches to provide catalytic properties to TMDs, regardless of the specific material. In this work, we show that even a theoretically poorly catalytic (and poorly studied) TMD, namely zirconium diselenide (ZrSe2), can act as an efficient EC for the hydrogen evolution reaction (HER) when exfoliated in the form of two-dimensional (2D) few-layer flakes. We critically show the difficulties of explaining the catalytic mechanisms of the resulting ECs in the presence of complex structural and chemical modifications, which are nevertheless evaluated extensively. By doing so, we also highlight the easiness of transforming 2D TMDs into effective HER-ECs. To strengthen our message in practical environments, we report ZrSe2-based acidic (proton exchange membrane [PEM]) and alkaline water electrolyzers operating at 400 mA cm–2 at a voltage of 1.88 and 1.92 V, respectively, thus competing with commercial technologies.
|
|
| 9. |
- Vonlanthen, René, et al.
(författare)
-
Toward a Consensus on Centralization in Surgery.
- 2018
-
Ingår i: Annals of surgery. - 1528-1140. ; 268:5, s. 712-724
-
Tidskriftsartikel (refereegranskat)abstract
- To critically assess centralization policies for highly specialized surgeries in Europe and North America and propose recommendations.Most countries are increasingly forced to maintain quality medicine at a reasonable cost. An all-inclusive perspective, including health care providers, payers, society as a whole and patients, has ubiquitously failed, arguably for different reasons in environments. This special article follows 3 aims: first, analyze health care policies for centralization in different countries, second, analyze how centralization strategies affect patient outcome and other aspects such as medical education and cost, and third, propose recommendations for centralization, which could apply across continents.Conflicting interests have led many countries to compromise for a health care system based on factors beyond best patient-oriented care. Centralization has been a common strategy, but modalities vary greatly among countries with no consensus on the minimal requirement for the number of procedures per center or per surgeon. Most national policies are either partially or not implemented. Data overwhelmingly indicate that concentration of complex care or procedures in specialized centers have positive impacts on quality of care and cost. Countries requiring lower threshold numbers for centralization, however, may cause inappropriate expansion of indications, as hospitals struggle to fulfill the criteria. Centralization requires adjustments in training and credentialing of general and specialized surgeons, and patient education.There is an obvious need in most areas for effective centralization. Unrestrained, purely "market driven" approaches are deleterious to patients and society. Centralization should not be based solely on minimal number of procedures, but rather on the multidisciplinary treatment of complex diseases including well-trained specialists available around the clock. Audited prospective database with monitoring of quality of care and cost are mandatory.
|
|
