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Non-fibrillar soluble oligomeric forms of amyloid-β peptide (oAβ) and tau proteins are likely to play a major role in Alzheimer’s disease (AD). The prevailing hypothesis on the disease etiopathogenesis is that oAβ initiates tau pathology that slowly spreads throughout the medial temporal cortex and neocortices independently of Aβ, eventually leading to memory loss. Here we show that a brief exposure to extracellular recombinant human tau oligomers (oTau), but not monomers, produces an impairment of long-term potentiation (LTP) and memory, independent of the presence of high oAβ levels. The impairment is immediate as it raises as soon as 20 min after exposure to the oligomers. These effects are reproduced either by oTau extracted from AD human specimens, or naturally produced in mice overexpressing human tau. Finally, we found that oTau could also act in combination with oAβ to produce these effects, as sub-toxic doses of the two peptides combined lead to LTP and memory impairment. These findings provide a novel view of the effects of tau and Aβ on memory loss, offering new therapeutic opportunities in the therapy of AD and other neurodegenerative diseases associated with Aβ and tau pathology.

Observational networks enhance real‐time situational awareness for emergency and water resource management during extreme weather events. We present examples of how a diverse, multitiered observational network in California provided insights into hydrometeorological processes and impacts during a 3‐day atmospheric river storm centered on 14 February 2019. This network, which has been developed over the past two decades, aims to improve understanding and mitigation of effects from extreme storms influencing water resources and natural hazards. We combine atmospheric reanalysis output and additional observations to show how the network allows: (1) the validation of record cool season precipitable water observations over southern California; (2) the identification of phenomena that produce natural hazards and present difficulties for short‐term weather forecast models, such as extreme precipitation amounts and snow level variability; (3) the use of soil moisture data to improve hydrologic model forecast skill in northern California's Russian River basin; and (4) the combination of meteorological data with seismic observations to identify when a large avalanche occurred on Mount Shasta. This case study highlights the value of investments in diverse observational assets and the importance of continued support and synthesis of these networks to characterize climatological context and advance understanding of processes modulating extreme weather. Key Points A multitiered observational network in California is evaluated during an extreme atmospheric river storm spanning 13–15 February 2019 The network validates record precipitable water and detects mesoscale atmospheric processes driving flood, snowfall, and mass wasting events Diverse, high frequency observational networks are valuable investments to aid water resource management and natural hazard mitigation

B. Spencer, S. Williams, E. Rockenstein, E. Valera, W. Xin, M. Mante, J. Florio, A. Adame, E. Masliah, and M.R. Sierks, \"α-Synuclein Conformational Antibodies Fused to Penetratin are Effective in Models of Lewy Body Disease,\" Annals of Clinical and Translational Neurology 3, no. 8 (2016): 588-606, https://doi.org/10.1002/acn3.321. The above article, published online on 16 June 2016, in Wiley Online Library (http://onlinelibrary.wiley.com/), has been retracted by agreement between the journal Editor-in-Chief, Ahmet Hoke; the American Neurological Association; and Wiley Periodicals LLC. Following publication, a third party contacted the publisher with concerns about duplications in Figures 1A, 3A, 3C, and 4A. Additionally, duplicated panels were discovered for Figure 5 with an earlier publication by some of the same authors (Fields et al., 2016 [https://doi.org/10.1186/s12974-016-0585-8]). The retraction has been agreed to because of evidence that significant portions of multiple figures were duplicated, affecting the interpretation of the data and results presented. Author Eliezer Masliah did not indicate his agreement with the retraction. The other authors did not respond to communications from the Publisher regarding the retraction.

alpha-Synuclein (alpha-syn) has been identified as the major component of Lewy bodies that characterize neurodegenerative synucleinopathies, including Parkinson's disease. Overexpression of alpha-syn, and prefibrillar alpha-syn oligomers, has been implicated in these pathologies; therefore, prevention of prefibril accumulation, and inhibition of other aberrant effects of overexpressed alpha-syn, could provide novel treatments. Here, we have selected a human single-chan Fv (scFv) antibody, D10, that binds human monomeric wild-type alpha-syn. We demonstrate, by retargeting assays and coimmunoprecipitation, that the D10 scFv is a specific and efficient intracellular antibody (intrabody). By transfecting the D10 scFv gene into an HEK 293 cell line that overexpresses wild-type alpha-syn, we show that the D10 intrabody stabilizes detergent-soluble monomeric alpha-syn and inhibits the formation of detergent-insoluble high-molecular-weight alpha-syn species. In addition, the D10 intrabody ameliorates the decreased cell adhesion that characterizes the alpha-syn-overexpressing cells. Given the important role of alpha-syn pathology, and the facility with which intrabodies can be further engineered in vitro, anti-alpha-syn intrabodies may represent novel molecular therapeutics for synucleinopathies, with implications for other neurodegenerative disorders caused by misfolded accumulated proteins.

The precise mass, bulk density, porosity and internal structure of the nucleus of comet 67P/Churyumov–Gerasimenko are calculated, on the basis of its gravity field, showing it to be dusty, homogeneous, low-density and highly porous. An 'icy dirtball' cometary nucleus We are familiar with the bright coma and characteristic dust and plasma tails of comets when observed from ground, but the nucleus itself is hidden inside the coma. Comet nuclei consist of dust and mostly water ice, but their internal structure is essentially unknown. This paper reports results from the Radio Science Investigation (RSI) experiment on the Rosetta spacecraft that provide the precise mass, bulk density, porosity and internal structure of the nucleus of comet 67P/Churyumov–Gerasimenko based on its gravity field. Results point to a low-density, highly porous nucleus containing four times more dust than ice by mass and two times more dust than ice by volume. The authors conclude that the interior of the nucleus is homogeneous and constant in density on a global scale, with no large voids. Cometary nuclei consist mostly of dust and water ice 1 . Previous observations have found nuclei to be low-density and highly porous bodies 2 , 3 , 4 , but have only moderately constrained the range of allowed densities because of the measurement uncertainties. Here we report the precise mass, bulk density, porosity and internal structure of the nucleus of comet 67P/Churyumov–Gerasimenko on the basis of its gravity field. The mass and gravity field are derived from measured spacecraft velocity perturbations at fly-by distances between 10 and 100 kilometres. The gravitational point mass is GM  = 666.2 ± 0.2 cubic metres per second squared, giving a mass M  = (9,982 ± 3) × 10 9 kilograms. Together with the current estimate of the volume of the nucleus 5 , the average bulk density of the nucleus is 533 ± 6 kilograms per cubic metre. The nucleus appears to be a low-density, highly porous (72–74 per cent) dusty body, similar to that of comet 9P/Tempel 1 2 , 3 . The most likely composition mix has approximately four times more dust than ice by mass and two times more dust than ice by volume. We conclude that the interior of the nucleus is homogeneous and constant in density on a global scale without large voids. The high porosity seems to be an inherent property of the nucleus material.

Vesta's surface is characterized by abundant impact craters, some with preserved ejecta blankets, large troughs extending around the equatorial region, enigmatic dark material, and widespread mass wasting, but as yet an absence of volcanic features. Abundant steep slopes indicate that impact-generated surface regolith is underlain by bedrock. Dawn observations confirm the large impact basin (Rheasilvia) at Vesta's south pole and reveal evidence for an earlier, underlying large basin (Veneneia). Vesta's geology displays morphological features characteristic of the Moon and terrestrial planets as well as those of other asteroids, underscoring Vesta's unique role as a transitional solar system body.

The Rosetta spacecraft has investigated comet 67P/Churyumov-Gerasimenko from large heliocentric distances to its perihelion passage and beyond. We trace the seasonal and diurnal evolution of the colors of the 67P nucleus, finding changes driven by sublimation and recondensation of water ice. The whole nucleus became relatively bluer near perihelion, as increasing activity removed the surface dust, implying that water ice is widespread underneath the surface. We identified large (1500 square meters) ice-rich patches appearing and then vanishing in about 10 days, indicating small-scale heterogeneities on the nucleus. Thin frosts sublimating in a few minutes are observed close to receding shadows, and rapid variations in color are seen on extended areas close to the terminator. These cyclic processes are widespread and lead to continuously, slightly varying surface properties.

The North American monsoon (NAM) is the main driver of summertime climate variability in the U.S. Southwest. Previous studies of the NAM have primarily focused on the Tier I region of the North American Monsoon Experiment (NAME), spanning central-western Mexico, southern Arizona, and New Mexico. This study, however, presents a climatological characterization of summertime precipitation, defined as July–September (JAS), in the Lake Mead watershed, located in the NAME Tier II region. Spatiotemporal variability of JAS rainfall is examined from 1981 to 2016 using gridded precipitation data and the meteorological mechanisms that account for this variability are investigated using reanalyses. The importance of the number of wet days (24-h rainfall ≥1 mm) and extreme rainfall events (95th percentile of wet days) to the total JAS precipitation is examined and shows extreme events playing a larger role in the west and central basin. An investigation into the dynamical drivers of extreme rainfall events indicates that anticyclonic Rossby wave breaking (RWB) in the midlatitude westerlies over the U.S. West Coast is associated with 89% of precipitation events >10 mm (98th percentile of wet days) over the Lake Mead basin. This is in contrast to the NAMETier I region where easterly upper-level disturbances such as inverted troughs are the dominant driver of extreme precipitation. Due to the synoptic nature of RWB events, corresponding impacts and hazards extend beyond the Lake Mead watershed are relevant for the greater U.S. Southwest.

The dwarf planet (1) Ceres, the largest object in the main asteroid belt, is found to have localized bright areas on its surface; particularly interesting is a bright pit on the floor of the crater Occator that exhibits what is likely to be water ice sublimation, producing crater-bound haze clouds with a diurnal rhythm. Possible ice sublimation on dwarf planet Ceres Images from NASA's Dawn orbiter spacecraft reveal localized bright areas on the surface of the dwarf planet Ceres, the largest object in the main asteroid belt. These unusual areas are consistent with the presence of hydrated magnesium sulfates mixed with dark background material, although other compositions are possible. Recent reports of water vapour, bound water and OH on Ceres raised the possibility there may be surface water there, and the new images reveal multiple bright spots on the floor of crater Occator that could be from surface ice. The largest of these, corresponding to the crater's central pit, produces haze clouds inside the crater with a diurnal rhythm, a clear indication of possible sublimation of water ice. The dwarf planet (1) Ceres, the largest object in the main asteroid belt 1 with a mean diameter of about 950 kilometres, is located at a mean distance from the Sun of about 2.8 astronomical units (one astronomical unit is the Earth–Sun distance). Thermal evolution models suggest that it is a differentiated body with potential geological activity 2 , 3 . Unlike on the icy satellites of Jupiter and Saturn, where tidal forces are responsible for spewing briny water into space, no tidal forces are acting on Ceres. In the absence of such forces, most objects in the main asteroid belt are expected to be geologically inert. The recent discovery 4 of water vapour absorption near Ceres and previous detection of bound water and OH near and on Ceres (refs 5 , 6 , 7 ) have raised interest in the possible presence of surface ice. Here we report the presence of localized bright areas on Ceres from an orbiting imager 8 . These unusual areas are consistent with hydrated magnesium sulfates mixed with dark background material, although other compositions are possible. Of particular interest is a bright pit on the floor of crater Occator that exhibits probable sublimation of water ice, producing haze clouds inside the crater that appear and disappear with a diurnal rhythm. Slow-moving condensed-ice or dust particles 9 , 10 may explain this haze. We conclude that Ceres must have accreted material from beyond the ‘snow line’ 11 , which is the distance from the Sun at which water molecules condense.

The Philae lander, part of the Rosetta mission to investigate comet 67P/Churyumov-Gerasimenko, was delivered to the cometary surface in November 2014. Here we report the precise circumstances of the multiple landings of Philae, including the bouncing trajectory and rebound parameters, based on engineering data in conjunction with operational instrument data. These data also provide information on the mechanical properties (strength and layering) of the comet surface. The first touchdown site, Agilkia, appears to have a granular soft surface (with a compressive strength of 1 kilopascal) at least ~20 cm thick, possibly on top of a more rigid layer. The final landing site, Abydos, has a hard surface.