Arctic sea-ice loss is a leading indicator of climate change and can be attributed, in large part, to atmospheric forcing. Here, we show that recent ice reductions, weakening of the halocline, and ...shoaling of the intermediate-depth Atlantic Water layer in the eastern Eurasian Basin have increased winter ventilation in the ocean interior, making this region structurally similar to that of the western Eurasian Basin. The associated enhanced release of oceanic heat has reduced winter sea-ice formation at a rate now comparable to losses from atmospheric thermodynamic forcing, thus explaining the recent reduction in sea-ice cover in the eastern Eurasian Basin. This encroaching “atlantification” of the Eurasian Basin represents an essential step toward a new Arctic climate state, with a substantially greater role for Atlantic inflows.
Member states of the United Nations (UN) agree that its development system needs substantial reform given its fragmentation and outdated structures, as well as new demands from the 2030 Agenda. Yet, ...a recent two-year reform process yielded no substantial reform decisions. Why did member states fail to endorse the necessary reforms despite almost unanimous recognition of the need for change? This paper describes member states' conflicting positions on reforming the UN and analyses their failure to delegate authority to the UN development system. North and South, donors and recipients, are locked in a struggle for power and control, maximising bilateral influence at the expense of the benefits of multilateral cooperation. The paper contributes to the pool of UN studies, adding a decidedly political perspective of the reform process. It is based on diplomatic statements, negotiation drafts and interviews with UN diplomats.
Commensal gut bacterial communities (microbiomes) are predicted to influence human health and disease
. Neonatal gut microbiomes are colonized with maternal and environmental flora and mature toward ...a stable composition over 2-3 years
. To study pre- and postnatal determinants of infant microbiome development, we analyzed 402 fecal metagenomes from 60 infants aged 0-8 months, using longitudinal generalized linear mixed models (GLMMs). Distinct microbiome signatures correlated with breastfeeding, formula ingredients, and maternal gestational weight gain (GWG). Amino acid synthesis pathway accretion in breastfed microbiomes complemented normative breastmilk composition. Prebiotic oligosaccharides, designed to promote breastfed-like microflora
, predicted functional pathways distinct from breastfed infant microbiomes. Soy formula in six infants was positively associated with Lachnospiraceae and pathways suggesting a short-chain fatty acid (SCFA)-rich environment, including glycerol to 1-butanol fermentation, which is potentially dysbiotic. GWG correlated with altered carbohydrate degradation and enriched vitamin synthesis pathways. Maternal and postnatal antibiotics predicted microbiome alterations, while delivery route had no persistent effects. Domestic water source correlates suggest water may be an underappreciated determinant of microbiome acquisition. Clinically important microbial pathways with statistically significant dietary correlates included dysbiotic markers
, core enterotype features
, and synthesis pathways for enteroprotective
and immunomodulatory
metabolites, epigenetic mediators
, and developmentally critical vitamins
, warranting further investigation.
Coulomb crystallization of highly charged ions Schmöger, L.; Versolato, O. O.; Schwarz, M. ...
Science (American Association for the Advancement of Science),
03/2015, Letnik:
347, Številka:
6227
Journal Article
Recenzirano
Control over the motional degrees of freedom of atoms, ions, and molecules in a field-free environment enables unrivalled measurement accuracies but has yet to be applied to highly charged ions ...(HCIs), which are of particular interest to future atomic clock designs and searches for physics beyond the Standard Model. Here, we report on the Coulomb crystallization of HCIs (specifically 40Ar13+) produced in an electron beam ion trap and retrapped in a cryogenic linear radiofrequency trap by means of sympathetic motional cooling through Coulomb interaction with a directly laser-cooled ensemble of Be+ ions. We also demonstrate cooling of a single Ar13+ ion by a single Be+ ion—the prerequisite for quantum logic spectroscopy with a potential 10–19 accuracy level. Achieving a seven-orders-of-magnitude decrease in HCI temperature starting at megakelvin down to the millikelvin range removes the major obstacle for HCI investigation with high-precision laser spectroscopy.
This research introduces 4 new constructs that reflect interrole conflict (i.e., work‐to‐personal, personal‐to‐work, family‐to‐personal, and personal‐to‐family conflict) and provide a more complete ...view of the roles and responsibilities employees experience outside of work. An integration of interrole conflict literature and research on work and nonwork roles or domains highlights the importance of considering an individual's personal domain, which includes activities one pursues because of his or her own interests (e.g., friends, hobbies, community). Unfortunately, without conflict measures pertaining to this new role, researchers cannot clearly understand how roles other than family interfere with individuals’ work role including how interrole conflict impacts employees who do not have significant responsibilities in the family domain. Five phases of research across 4 separate samples were conducted in order to develop measures for the 4 new conflict constructs and to examine relationships with important work, family, life, and health outcomes. Findings from multisource data, including self‐rated, coworker‐rated, as well as single and nonsingle participants, show that the 4 new forms of interrole conflict have significant implications for employees and organizations.
A 15-yr duration record of mooring observations from the eastern (>70°E) Eurasian Basin (EB) of the Arctic Ocean is used to show and quantify the recently increased oceanic heat flux from ...intermediate-depth (∼150–900 m) warm Atlantic Water (AW) to the surface mixed layer and sea ice. The upward release of AW heat is regulated by the stability of the overlying halocline, which we show has weakened substantially in recent years. Shoaling of the AW has also contributed, with observations in winter 2017–18 showing AW at only 80 m depth, just below the wintertime surface mixed layer, the shallowest in our mooring records. The weakening of the halocline for several months at this time implies that AW heat was linked to winter convection associated with brine rejection during sea ice formation. This resulted in a substantial increase of upward oceanic heat flux during the winter season, from an average of 3–4 W m−2 in 2007–08 to >10 W m−2 in 2016–18. This seasonal AW heat loss in the eastern EB is equivalent to a more than a twofold reduction of winter ice growth. These changes imply a positive feedback as reduced sea ice cover permits increased mixing, augmenting the summer-dominated ice-albedo feedback.
The recent advances in relative protein-ligand binding free energy calculations have shown the value of alchemical methods in drug discovery. Accurately assessing absolute binding free energies, ...although highly desired, remains a challenging endeavour, mostly limited to small model cases. Here, we demonstrate accurate first principles based absolute binding free energy estimates for 128 pharmaceutically relevant targets. We use a novel rigorous method to generate protein-ligand ensembles for the ligand in its decoupled state. Not only do the calculations deliver accurate protein-ligand binding affinity estimates, but they also provide detailed physical insight into the structural determinants of binding. We identify subtle rotamer rearrangements between apo and holo states of a protein that are crucial for binding. When compared to relative binding free energy calculations, obtaining absolute binding free energies is considerably more challenging in large part due to the need to explicitly account for the protein in its apo state. In this work we present several approaches to obtain apo state ensembles for accurate absolute Δ
G
calculations, thus outlining protocols for prospective application of the methods for drug discovery.
Molecular dynamics based absolute protein-ligand binding free energies can be calculated accurately and at large scale to facilitate drug discovery.
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