bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impacts of Autumnal Eurasian Snow Cover on Predominant Modes of Boreal Winter Surface Air Temperature Over Eurasia
Authors: Han Shuangze , Sun Jianqi 
Published: August 2018

AbstractIn the present paper, the linkage between the predominant modes of boreal winter surface air temperature (SAT) anomalies over Eurasia and the preceding autumnal Eurasian snow cover is investigated for the period of 1979–2014. The first leading winter Eurasian SAT mode exhibits a strong signal over the region northward from 40°N; in association with this SAT mode, a significant zonal dipole pattern in snow cover can be observed in the midlatitude Eurasia during November. Such anomalous November snow cover strengthens the wave activity flux upward propagating over the middle latitudes, which can change the stratospheric polar vortex thereafter. In the following winter, the anomalous polar vortex signal propagates downward to the surface and gives rise to the negative Arctic Oscillation‐like structure. Consequently, this leads to the winter SAT anomalies occupying the area north of 40°N. The second leading winter Eurasian SAT mode shows negative values northward from 60°N as well as positive over the middle latitudes of Eurasia; in association with the second SAT mode, the significant anomalous snow cover appears to the east of the Ural Mountains during October. Such an anomalous snow signal can persist from October until the subsequent winter and produce a wave‐like structure with a southeastward propagation from the Ural Mountains to the midlatitude Eurasia in the midtroposphere and upper troposphere, which results in the dipole anomalous temperatures lying in the middle to high latitudes of Eurasia. The preceding autumn snow cover signal is valuable for the prediction of the winter SAT over the Eurasian continent.
Triggered Lightning Return Stroke Luminosity up to 1 km in Two Optical Bands
Authors: Carvalho F. L. , Uman M. A. , Jordan D. M. , Wilkes R. A. , Kotovsky D. A. 
Published: August 2018

AbstractLuminosity waveforms measured using two types of avalanche photodiodes (APDs) are presented as a function of time and channel height for 15 triggered‐lightning return strokes. Short vertical sections of 20 channel heights ranging from 0 to 1 km were observed by both types of APDs. For APD type I, the return stroke luminosity waveforms decay faster following a single initial peak (IP) than the waveforms recorded by APD type II, which often exhibit a second maximum (SM) following the IP, though the risetimes of the initial luminosity wavefront preceding the IP are similar for both types of APDs. APD type II responds better to longer wavelengths than APD type I, and since the SM occurs about 10 μs after the IP at the channel‐bottom and about 20 μs after the IP at 1‐km height, the SM is likely a consequence of spectral lines excited during the cooling of the channel, following the initial high‐temperature/pressure stage. The initial optical radiation during the return stroke is likely dominated by ionized atomic species radiated at higher temperatures (NII lines between 450 and 600 nm) better captured by APD type I, while the later optical radiation is likely due to neutral atomic species radiated at lower temperatures (e.g., H‐alpha at 656.3 nm, OI at 715.7 nm and 777.4 nm, and the NI at 744.4 nm) better captured by APD type II. The average IP upward speed is 1.3e8 m/s, while the average SM upward speed is 3.1e7 m/s.
Geochemical Trends in the Burns Formation Layered Sulfate Deposits at Meridiani Planum, Mars, and Implications for Their Origin
Authors: McCollom Thomas M. 
Published: August 2018

AbstractThe layered deposits that comprise the Burns formation at Meridiani Planum have a chemical composition that closely resembles Martian basalts with addition of an oxidized sulfur component. Alternative scenarios proposed to explain this composition differ over whether the sulfur component was added by itself (sulfur only) or was accompanied by transport of other elements, primarily Mg, Fe, and Ca (sulfur‐plus‐cations). Analysis of trends in elemental abundance relative to SO3 and TiO2 indicates that many elements, including Si, Al, K, Na, P, Cr, and Ti, were essentially immobile during the addition of the sulfur component and throughout all subsequent diagenetic processes. Conversely, the divalent cations (Fe, Mg, Ca, Mn, and Zn) were mobilized during diagenesis. This mobilization obscures any trends in composition that were established prior to diagenesis, making it difficult to determine whether these elements were transported into the materials along with sulfur or not. Mass balance models indicate that the current compositions can plausibly be accounted for by either sulfur‐only or sulfur‐plus‐cations scenarios. However, the sulfur‐plus‐cations scenario requires that the bedrocks had a much more complex geochemical history in order to arrive at their present chemical composition, including highly variable compositions prior to diagenetic alteration and extensive mobilization of elements during diagenesis. Conversely, sulfur‐only scenarios are consistent with the evidence for immobility of many elements and require only limited mobilization of cations during diagenesis. Overall, sulfur‐only scenarios provide a much simpler and more straightforward means of accounting for the chemical composition of the Burns formation than scenarios that involve cation mobility.
Hydrological Controls on the Seasonal Variability of Dissolved and Particulate Black Carbon in the Altamaha River, GA
Authors: Roebuck J. Alan , Medeiros Patricia M. , Letourneau Maria L. , Jaffé Rudolf 
Published: August 2018

AbstractRivers play an important role in the transport of organic carbon from terrestrial to marine environments. A significant portion of this material is black carbon (BC), a residue of incomplete biomass and fossil fuel combustion. BC is mobilized in fluvial systems as both particulate BC (PBC) and dissolved BC (DBC), and the export of BC to coastal environments may have significant implications for carbon cycling in marine environments. However, while little is known regarding the potential connectivity between riverine export of PBC and DBC or the potential importance of such a relationship in constraining future BC budgets, current knowledge suggests that fluvial export of PBC and DBC are decoupled in small fire‐impacted watersheds. This study aims to further address this subject on a larger watershed scale. For this study, 13 monthly samples were collected (September 2015 to September 2016) near the mouth of the Altamaha River, Georgia. PBC and DBC were characterized using the benzenze polycarboxylic acid method. Seasonal hydrology and regional shifts in storm events play an important role for both PBC and DBC export during high flow months. The DBC concentrations were comparable among wet and dry seasons, whereas evidence of seasonal salt water intrusions suggests an additional estuarine contribution of PBC at the sampling location. The DBC and PBC fluxes were generally coupled, although this pattern was disrupted during initial storm pulses. While this is the first report of potential coupling between DBC and PBC export, environmental drivers controlling this behavior between DBC and PBC remain to be constrained.
Estimating Soil Respiration in a Subalpine Landscape Using Point, Terrain, Climate, and Greenness Data
Authors: Berryman Erin M. , Vanderhoof Melanie K. , Bradford John B. , Hawbaker Todd J. , Henne Paul D. , Burns Sean P. , Frank John M. , Birdsey Richard A. , Ryan Michael G. 
Published: August 2018

AbstractLandscape carbon (C) flux estimates help assess the ability of terrestrial ecosystems to buffer further increases in anthropogenic carbon dioxide (CO2) emissions. Advances in remote sensing have led to coarse‐scale estimates of gross primary productivity (GPP; e.g., MODIS 17), yet efforts to develop spatial respiration products are lacking. Here we demonstrate a method to predict growing season soil respiration at a regional scale in a mixed subalpine ecosystem. We related field measurements (n = 396) of growing season soil respiration mostly from subalpine forests in the Southern Rocky Mountains ecoregion to a suite of biophysical predictors using a Random Forest model (30‐m pixel size). We found that Landsat Enhanced Vegetation Index, growing season aridity index, temperature, precipitation, elevation, and slope aspect explained spatiotemporal variability in soil respiration. Our model had a psuedo‐r2 of 0.45 and root‐mean‐square error of roughly one quarter of the mean value of respiration. Predicted growing season soil respiration across the region was remarkably consistent across 2004, 2005, and 2006 (150‐day sums of 542.8, 544.3, and 536.5 g C/m2, respectively). Yet we observed substantial variability in spatial patterns of soil respiration predictions that varied among years, suggesting that our method is sensitive to changes in respiration drivers. Mean predicted growing season soil respiration was 73% of MODIS GPP, while predicted soil respiration was generally within 20% of nocturnal net ecosystem exchange from nearby eddy covariance towers. Thus, geospatial and remotely sensed data sets can be used to estimate soil respiration at landscape scales.
Deglacial Warming and Hydroclimate Variability in the Central Indonesian Archipelago
Authors: Schröder Jan F. , Kuhnt Wolfgang , Holbourn Ann , Beil Sebastian , Zhang Peng , Hendrizan Marfasran , Xu Jian 
Published: August 2018

AbstractWe present centennial‐scale records of sea surface temperature and oxygen isotopes from the Celebes Sea, Makassar Strait, Flores Sea, and northwestern Banda Sea, which provide new insights into the variability of Indonesian hydroclimate over the past 25 kyr. Deglacial warming was generally gradual with an amplitude of 3–4 °C. Statistical evaluation of the temperature data suggests that the onset of deglacial sea surface temperatures warming in the tropical Indonesian Sea occurred earlier than the global atmospheric CO2 rise. In contrast to previous terrestrial precipitation records, our ice volume‐corrected δ18O of seawater (δ18Osw) does not support widespread aridity in central Indonesia during the last glacial period. While δ18Osw was substantially enriched during Heinrich Stadial 1 and the Younger Dryas, δ18Osw values were only ~0.2‰ heavier during the Last Glacial Maximum than during the Holocene. Heavier δ18Osw during Heinrich Stadial 1 and the Younger Dryas either reflects a decline in precipitation amount and/or increased δ18O of rainfall in central Indonesia, both likely caused by a southward displacement of the tropical rain belt. Comparison of the Celebes Sea, Makassar Strait, Flores Sea, and Banda Sea records suggests that rainfall isotope and/or amount changes were comparable over Borneo and Sulawesi during the last termination.
The Wilson Cycle and Effects of Tectonic Structural Inheritance on Rifted Passive Margin Formation
Authors: Salazar‐Mora Claudio A. , Huismans Ritske S. , Fossen Haakon , Egydio‐Silva Marcos 
Published: August 2018

AbstractThe parallelism between older collisional belts and younger rift systems is widely known and particularly well portrayed along the Atlantic Ocean. How tectonic inherited and new‐formed shear zones control rift nucleation and the final architecture of rifted conjugate passive margins is still poorly understood. Here we present lithospheric‐scale thermo‐mechanical numerical models that self‐consistently create extensional and contractional tectonic inheritance, where prior extension and contraction are systematically varied. Our results show that (1) initial reactivation occurs along the former lithospheric suture zones; (2) upper crustal thick‐skinned basement thrusts are partially or fully reactivated depending on the amount of prior contraction and size of the orogen; (3) with a small amount of contraction, thick‐skinned thrusts are efficiently reactivated in extension and provide the template for rifted margin formation; (4) with larger amounts of contraction, thick‐skinned thrusts distal to the lithospheric suture zone do not reactivate in extension; and (5) reactivation of prior contractional shear zones dominates during the early stages of rifting, while during the final stage of margin formation new‐formed extensional shear zones dominate. Force balance analysis predicts an inverse relation between midcrustal viscosity and the maximum offset for reactivation of weak upper crustal structures. Force balance also predicts that the degree of weakening or healing of the weak suture and the thermal thinning of the necking area control at which stage suture reactivation is deactivated and extension proceeds by mantle lithosphere thermal necking. Two rifted conjugate margins with orogenic inheritance in the North and South Atlantic are used for comparison.
Alpinetin exerts anti-colitis efficacy by activating AhR, regulating miR-302/DNMT-1/CREB signals, and therefore promoting Treg differentiation
Authors: Lv Qi , Shi Can , Qiao Simiao , Cao Na , Guan Chunge , Dai Yue , Wei Zhifeng 
Published: August 2018

AbstractAlpinetin, a flavonoid compound extracted from the seeds of Alpinia katsumadai Hayata, has been demonstrated to exert massive biological properties. This study aimed to evaluate the effect of alpinetin on dextran sulfate sodium (DSS)-induced colitis, and elucidate the potential mechanisms. Alpinetin significantly alleviated colitis in mice, accompanied with restored Th17/Treg balance in colons. In vitro, alpinetin directly promoted Treg differentiation but exerted little effect on Th17 differentiation, and the action was in an aryl hydrocarbon receptor (AhR)-dependent manner. It acted as a potential AhR activator, evidenced by increased expression of CYP1A1, dissociation of AhR/HSP90 complexes, AhR nuclear translocation, XRE-driven luciferase reporter gene and DNA-binding activity of AhR/ARNT/XRE in T cells. Furthermore, alpinetin significantly promoted expression of miR-302 but not others, and restrained expression of DNMT-1 and methylation level of Foxp3 promoter region in CD4+ T cells and colons of colitis mice. However, the association of CREB and Foxp3 promoter region but not expression, nuclear translocation and DNA-binding activity of CREB was up-regulated by alpinetin in CD4+ T cells. The relationship of alpinetin-adjusted AhR activation, expressions of miR-302 and DNMT-1, association of CREB and Foxp3 promoter region, and Treg differentiation was confirmed by using CH223191, siAhR, miR-302 inhibitor and pcDNA3.1(+)-mDNMT-1. Finally, CH223191 abolished the amelioration of alpinetin on colitis, induction of Treg cells and regulation of miR-302/DNMT-1/CREB signals in colons of colitis mice. In conclusion, alpinetin ameliorated colitis in mice via activating AhR, regulating miR-302/DNMT-1/CREB signals, therefore promoting Treg differentiation.
Dual role of autophagy on docetaxel-sensitivity in prostate cancer cells
Authors: Cristofani Riccardo , Montagnani Marelli Marina , Cicardi Maria Elena , Fontana Fabrizio , Marzagalli Monica , Limonta Patrizia , Poletti Angelo , Moretti Roberta Manuela 
Published: August 2018

AbstractProstate cancer (PC) is one of the leading causes of death in males. Available treatments often lead to the appearance of chemoresistant foci and metastases, with mechanisms still partially unknown. Within tumour mass, autophagy may promote cell survival by enhancing cancer cells tolerability to different cell stresses, like hypoxia, starvation or those triggered by chemotherapic agents. Because of its connection with the apoptotic pathways, autophagy has been differentially implicated, either as prodeath or prosurvival factor, in the appearance of more aggressive tumours. Here, in three PC cells (LNCaP, PC3, and DU145), we tested how different autophagy inducers modulate docetaxel-induced apoptosis. We selected the mTOR-independent disaccharide trehalose and the mTOR-dependent macrolide lactone rapamycin autophagy inducers. In castration-resistant PC (CRPC) PC3 cells, trehalose specifically prevented intrinsic apoptosis in docetaxel-treated cells. Trehalose reduced the release of cytochrome c triggered by docetaxel and the formation of aberrant mitochondria, possibly by enhancing the turnover of damaged mitochondria via autophagy (mitophagy). In fact, trehalose increased LC3 and p62 expression, LC3-II and p62 (p62 bodies) accumulation and the induction of LC3 puncta. In docetaxel-treated cells, trehalose, but not rapamycin, determined a perinuclear mitochondrial aggregation (mito-aggresomes), and mitochondria specifically colocalized with LC3 and p62-positive autophagosomes. In PC3 cells, rapamycin retained its ability to activate autophagy without evidences of mitophagy even in presence of docetaxel. Interestingly, these results were replicated in LNCaP cells, whereas trehalose and rapamycin did not modify the response to docetaxel in the ATG5-deficient (autophagy resistant) DU145 cells. Therefore, autophagy is involved to alter the response to chemotherapy in combination therapies and the response may be influenced by the different autophagic pathways utilized and by the type of cancer cells.
Roles of Nmnat1 in the survival of retinal progenitors through the regulation of pro-apoptotic gene expression via histone acetylation
Authors: Kuribayashi Hiroshi , Baba Yukihiro , Iwagawa Toshiro , Arai Eisuke , Murakami Akira , Watanabe Sumiko 
Published: August 2018

AbstractLeber congenital amaurosis (LCA) is a severe, genetically heterogeneous dystrophy of the retina and mutations in the nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) gene is one of causal factors of LCA. NMNAT1 is a nuclear enzyme essential for nicotinamide adenine dinucleotide (NAD) biosynthesis pathways, but the mechanisms underlying the LCA pathology and whether NMNAT1 has a role in normal retinal development remain unclear. Thus, we examined the roles of Nmnat1 in retinal development via short hairpin (sh)-RNA-mediated downregulation. Retinal explants expressing sh-Nmnat1 showed large numbers of apoptotic retinal progenitor cells in the inner half of the neuroblastic layer. Decreased intracellular NAD content was observed and the addition of NAD to the culture medium attenuated sh-Nmnat1-induced apoptosis. Of the nuclear Sirtuin (Sirt) family, the expression of sh-Sirt1 and sh-Sirt6 resulted in a phenotype similar to that of sh-Nmnat1. Sirt proteins are histone deacetylases and the expression of sh-Nmnat1 increased the levels of acetylated histones H3 and H4 in the retina. Expression of sh-Nmnat1 resulted in significantly increased expression of Noxa and Fas, two pro-apoptotic genes. Acetylation of the genomic 5′-untranslated regions of Noxa and Fas loci was upregulated by sh-Nmnat1 expression. The co-expression of sh-Fas with sh-Nmnat1 reduced the number of apoptotic cells induced by sh-Nmnat1 expression alone. Taken together, our data suggested that the increased expression of Noxa and Fas explains, at least in part, the phenotype associated with sh-Nmnat1 in the retina. Taken together, these findings demonstrate the importance of the NAD biosynthesis pathway in normal development of the retina.
Combining discovery and targeted proteomics reveals a prognostic signature in oral cancer
Authors: Carnielli Carolina Moretto , Macedo Carolina Carneiro Soares , De Rossi Tatiane , Granato Daniela Campos , Rivera César , Domingues Romênia Ramos , Pauletti Bianca Alves , Yokoo Sami , Heberle Henry , Busso-Lopes Ariane Fidelis , Cervigne Nilva Karla , Sawazaki-Calone Iris , Meirelles Gabriela Vaz , Marchi Fábio Albuquerque , Telles Guilherme Pimentel , Minghim Rosane , Ribeiro Ana Carolina Prado , Brandão Thaís Bianca , de Castro Gilberto , González-Arriagada Wilfredo Alejandro , Gomes Alexandre , Penteado Fabio , Santos-Silva Alan Roger , Lopes Márcio Ajudarte , Rodrigues Priscila Campioni , Sundquist Elias , Salo Tuula , da Silva Sabrina Daniela , Alaoui-Jamali Moulay A. , Graner Edgard , Fox Jay W. , Coletta Ricardo Della , Paes Leme Adriana Franco 
Published: August 2018

AbstractDifferent regions of oral squamous cell carcinoma (OSCC) have particular histopathological and molecular characteristics limiting the standard tumor−node−metastasis prognosis classification. Therefore, defining biological signatures that allow assessing the prognostic outcomes for OSCC patients would be of great clinical significance. Using histopathology-guided discovery proteomics, we analyze neoplastic islands and stroma from the invasive tumor front (ITF) and inner tumor to identify differentially expressed proteins. Potential signature proteins are prioritized and further investigated by immunohistochemistry (IHC) and targeted proteomics. IHC indicates low expression of cystatin-B in neoplastic islands from the ITF as an independent marker for local recurrence. Targeted proteomics analysis of the prioritized proteins in saliva, combined with machine-learning methods, highlights a peptide-based signature as the most powerful predictor to distinguish patients with and without lymph node metastasis. In summary, we identify a robust signature, which may enhance prognostic decisions in OSCC and better guide treatment to reduce tumor recurrence or lymph node metastasis.
RAS at the Golgi antagonizes malignant transformation through PTPRκ-mediated inhibition of ERK activation
Authors: Casar Berta , Badrock Andrew P. , Jiménez Iñaki , Arozarena Imanol , Colón-Bolea Paula , Lorenzo-Martín L. Francisco , Barinaga-Rementería Irene , Barriuso Jorge , Cappitelli Vincenzo , Donoghue Daniel J. , Bustelo Xosé R. , Hurlstone Adam , Crespo Piero 
Published: August 2018

AbstractRAS GTPases are frequently mutated in human cancer. H- and NRAS isoforms are distributed over both plasma-membrane and endomembranes, including the Golgi complex, but how this organizational context contributes to cellular transformation is unknown. Here we show that RAS at the Golgi is selectively activated by apoptogenic stimuli and antagonizes cell survival by suppressing ERK activity through the induction of PTPRκ, which targets CRAF for dephosphorylation. Consistently, in contrast to what occurs at the plasma-membrane, RAS at the Golgi cannot induce melanoma in zebrafish. Inactivation of PTPRκ, which occurs frequently in human melanoma, often coincident with TP53 inactivation, accelerates RAS-ERK pathway-driven melanomagenesis in zebrafish. Likewise, tp53 disruption in zebrafish facilitates oncogenesis driven by RAS from the Golgi complex. Thus, RAS oncogenic potential is strictly dependent on its sublocalization, with Golgi complex-located RAS antagonizing tumor development.
Precipitation thresholds regulate net carbon exchange at the continental scale
Authors: Liu Zhihua , Ballantyne Ashley P. , Poulter Benjamin , Anderegg William R. L. , Li Wei , Bastos Ana , Ciais Philippe 
Published: August 2018

AbstractUnderstanding the sensitivity of ecosystem production and respiration to climate change is critical for predicting terrestrial carbon dynamics. Here we show that the primary control on the inter-annual variability of net ecosystem carbon exchange switches from production to respiration at a precipitation threshold between 750 and 950 mm yr−1 in the contiguous United States. This precipitation threshold is evident across multiple datasets and scales of observation indicating that it is a robust result and provides a new scaling relationship between climate and carbon dynamics. However, this empirical precipitation threshold is not captured by dynamic global vegetation models, which tend to overestimate the sensitivity of production and underestimate the sensitivity of respiration to water availability in more mesic regions. Our results suggest that the short-term carbon balance of ecosystems may be more sensitive to respiration losses than previously thought and that model simulations may underestimate the positive carbon–climate feedbacks associated with respiration.