bluuebunny/crossref_metadata_2025_split huggingface dataset:
DERIVATION RELATION FOR FINITE MULTIPLE ZETA VALUES IN
Authors: MURAHARA HIDEKI , ONOZUKA TOMOKAZU 
Published: January 2020

AbstractIhara et al. proved the derivation relation for multiple zeta values. The first-named author obtained its counterpart for finite multiple zeta values in ${\mathcal{A}}$. In this paper, we present its generalization in $\widehat{{\mathcal{A}}}$.
Community transformation through certified organic cotton initiatives—an analysis of case studies in Peru, Tanzania and India
Authors: Altenbuchner Christine , Vogel Stefan , Larcher Manuela 
Published: January 2020

AbstractThis paper examines how certified organic cotton initiatives (COCIs) influence community capitals in rural Peru, Tanzania and India using the community capitals framework (CCF). Case study analyses, including qualitative interviews of farmers, expert interviews and participatory observations, were conducted in Northern Peru, Northern Tanzania and Eastern India. The results show slight changes in community capitals in Peru, while comprehensive changes and spiraling-up effects were triggered by certified organic cotton farming initiatives in Tanzania and India. These community developments strongly depended on set measures, such as the extent of (1) partnership (e.g., contract farming), (2) input support (e.g., seeds, loans, community infrastructure), (3) capacity building (through training and advisory services), (4) group formation and (5) formation of cooperatives. Favorable environmental conditions and supporting local institutions facilitated spiraling-up effects, while social preconditions (e.g., gender inequality) strongly limited these effects. The research showed that COCIs have considerable potential to trigger spiraling-up effects in rural communities. However, the capacity strongly depends on the respective initiative and its ability to involve and empower farmers, i.e., to build up human and social capital.
Response of Extreme Rainfall for Landfalling Tropical Cyclones Undergoing Extratropical Transition to Projected Climate Change: Hurricane Irene (2011)
Authors: Liu M. , Yang L. , Smith J. A. , Vecchi G. A. 
Published: January 2020

AbstractExtreme rainfall and flooding associated with landfalling tropical cyclones (TCs) have large societal impacts, both in fatalities and economic losses. This study examines the response of TC rainfall to climate change projected under future anthropogenic greenhouse emissions, focusing on Hurricane Irene, which produced severe flooding across the Northeastern United States in August 2011. Numerical simulations are made with the Weather Research and Forecasting model, placing Irene in the present‐day climate and one projected for the end of 21st century climate represented by Phase 5 of the Coupled Model Intercomparison Project Representative Concentration Pathway 8.5 scenario. Projected future changes to surface and atmospheric temperature lead to a storm rainfall increase of 32% relative to the control run, exceeding the rate expected by the Clausius‐Clapeyron relation given a ~3‐K lower atmospheric warming. Analyses of the atmospheric water balance highlight contributions to the increase in rainfall rate from both increased circulation strength and atmospheric moisture. Storm rainfall rate shows contrasting response to global warming during TC and extratropical transition periods. During the TC phase, Irene shows a significant increase of storm rainfall rate in inner core regions. This increase shifts to outer rainbands as Irene undergoes extratropical transition, collocated with the maximum tangential wind increase and the change of secondary circulation strength. Changes of storm track from the control run to global warming projections play a role in the change of spatial rainfall pattern. Distinct roles of surface and atmospheric warming in storm rainfall and structure changes are also examined.
Ferropericlase Control of Lower Mantle Rheology: Impact of Phase Morphology
Authors: Thielmann M. , Golabek G. J. , Marquardt H. 
Published: January 2020

AbstractThe rheological properties of Earth's lower mantle play a key role for global mantle dynamics. The mineralogy of the lower mantle can be approximated as a bridgmanite‐ferropericlase mixture. Previous work has suggested that the deformation of this mixture might be dramatically affected by the large differences in viscosity between bridgmanite and ferropericlase. Here, we employ numerical models to establish a connection between ferropericlase morphology and the effective rheology of the Earth's lower mantle using a numerical‐statistical approach. Using this approach, we link the statistical properties of the two‐phase composite to its effective viscosity tensor using analytical approximations. We find that ferropericlase develops elongated structures within the bridgmanite matrix that result in significantly lowered viscosity. While our findings confirm previous endmember models that suggested a change of mantle viscosity due to the formation of interconnected weak layers, we show that significant rheological weakening can thus be already achieved even when ferropericlase does not form an interconnected network. Additionally, the alignment of weak ferropericlase leads to a pronounced viscous anisotropy that develops with total strain, which may have implications for understanding the viscosity structure of Earth's lower mantle as well as for modeling the behavior of subducting slabs. We show that to capture the effect of ferropericlase elongation on the effective viscosity tensor (and its anisotropy) in large‐scale mantle convection models, the analytical approximations that have been derived to describe the evolution of the effective viscosity of a two‐phase medium with aligned elliptical inclusions can be used.
Cementation Failure Behavior of Consolidated Gas Hydrate‐Bearing Sand
Authors: Wu Peng , Li Yanghui , Liu Weiguo , Sun Xiang , Kong Xianjing , Song Yongchen 
Published: January 2020

AbstractThe macromechanical properties (strength, stiffness, stress‐strain relationship, etc) of the hydrate‐bearing sediment are often correlated with the hydrate cementation failure behavior. In this study, a consolidated drained triaxial shear test with X‐ray computed tomography was conducted on a hydrate‐bearing sediment with a hydrate saturation of 32.1% under 3 MPa effective confining pressure for revealing the cementation failure behavior. The hydrate occurrences were clearly identified to be cementing, grain‐coating, prepatchy cluster and patchy cluster. The cementation failure behavior (morphology), deformation evolution (quantitative statistics), and localized shear deformation at different regions of stress‐strain curve were observed and analyzed using computed tomography. In the linearity region, the hydrate‐cemented clusters moved as a whole, while small hydrate particles would aggregate to the periphery of the clusters. The noncemented sand particles move disorderly during this process. Localized deformation occurred perfectly exhibit an antisymmetric bifurcation pattern. In the plasticity region, the specimen starts to deform plastically; an internal shear band occurs in the specimen. The hydrates begin to shed from the periphery of the cemented structure, and the grinding effect of hydrates begins to occur between sand particles. However, the shedded hydrates will not enter and fill the neighboring pores but hind the movement of sand particles structurally near the original position. In the yielding region, the hydrate‐cemented cluster structure is completely damaged and crushed into small pieces; a shear band with a determined thickness and inclination angle was observed.
Iron Isotope Behavior During Melt‐Peridotite Interaction in Supra‐subduction Zone Ophiolite From Northern Tibet
Authors: Zhang Long , Sun Wei‐dong , Zhang Zhao‐Feng , An Yajun , Liu Fang 
Published: January 2020

AbstractMelt‐peridotite interaction has the ability to modify the δ56Fe of peridotite. However, iron isotopic fractionation during melt‐peridotite interaction is not well understood at present. In this study, we present high‐precision iron isotopic data for serpentinized and carbonated peridotite from the Yushigou supra‐subduction zone ophiolite in the North Qilian orogen of northern Tibet, to provide insights into iron isotope behavior during melt‐peridotite interaction in the mantle wedge. High‐Cr and high‐Al dunites coexist with harzburgite in the Yushigou ophiolite. The high‐Cr and high‐Al dunites were produced by interaction of peridotite with boninitic melt and tholeiitic melt, respectively. Serpentinization and carbonation have negligible influence on δ56Fe of the peridotite. The harzburgite mostly has δ56Fe ranging from −0.055 ± 0.029‰ to 0.056 ± 0.030‰, which overlaps with δ56Fe of abyssal peridotite. The high‐Al dunite is enriched in FeO, but it has δ56Fe (0.004 ± 0.034‰–0.083 ± 0.064‰) similar to the harzburgite. In contrast, the high‐Cr dunite displays a large range in δ56Fe from −0.173 ± 0.017‰ to 0.173 ± 0.057‰. Moreover, δ56Fe of the high‐Cr dunite is negatively correlated with its FeO content, which is ascribed to kinetic iron isotopic fractionation during melt‐peridotite interaction. Surprisingly, distinct iron isotope behavior during melt‐peridotite interaction recorded by the Yushigou peridotite can well explain the large variation of FeO and δ56Fe in abyssal peridotite and mantle wedge peridotite on a global scale.
Late Quaternary East Asian Summer Monsoon Variability Deduced From Lacustrine Mineral Magnetic Records of Dahu Swamp, Southern China
Authors: Wei Zhiqiang , Zhong Wei , Xue Jibin , Ouyang Jun , Shang Shengtan , Ye Susu , Cao Jiayuan , Li Mingkun 
Published: January 2020

AbstractThe lack of long‐term and well‐preserved terrestrial archives from southern China largely impedes our understanding of past variability in the East Asian summer monsoon (EASM). In this study, we developed rainfall/precipitation‐related records by conducting a systematic mineral‐magnetic investigation on Dahu Swamp sediments over the past ~47.0 ka. The integrated magnetic results show that the magnetic minerals in the sediments were mainly catchment derived, likely reflecting hydroclimatic changes associated with EASM strength. In combination with other climatic proxies, our magnetic records reveal a relatively wet climate during the middle‐late Marine Oxygen Isotope Stage 3 and the Holocene and a relatively dry climate during the Marine Oxygen Isotope Stage 2, which broadly follow the precession‐induced summer insolation changes in the middle‐low latitudes of the Northern Hemisphere. The regional heterogeneity of the EASM rainfall evolution might be ascribed to the changes in timing and duration of Mei‐yu Front in China, which were closely associated with the El Niño/Southern Oscillation activities through its effects on the Western Pacific Subtropical High position. Long‐term climatic patterns inferred from Dahu Swamp were broadly similar to those of the Western Pacific Warm Pool region, especially during the mid‐Holocene rainfall optimum period, further supporting that the thermal mean states of the tropical Pacific associated with El Niño/Southern Oscillation modes may influence EASM precipitation. Our results highlight the coupled influence of external insolation forcing and internal low‐latitude processes on the spatial and temporal EASM variability, and understanding these influences could be critical to the prediction of future monsoon behavior under ongoing and future global warming.
Ultrafast relaxation of photoexcited superfluid He nanodroplets
Authors: Mudrich M. , LaForge A. C. , Ciavardini A. , O’Keeffe P. , Callegari C. , Coreno M. , Demidovich A. , Devetta M. , Fraia M. Di , Drabbels M. , Finetti P. , Gessner O. , Grazioli C. , Hernando A. , Neumark D. M. , Ovcharenko Y. , Piseri P. , Plekan O. , Prince K. C. , Richter R. , Ziemkiewicz M. P. , Möller T. , Eloranta J. , Pi M. , Barranco M. , Stienkemeier F. 
Published: January 2020

AbstractThe relaxation of photoexcited nanosystems is a fundamental process of light–matter interaction. Depending on the couplings of the internal degrees of freedom, relaxation can be ultrafast, converting electronic energy in a few fs, or slow, if the energy is trapped in a metastable state that decouples from its environment. Here, we study helium nanodroplets excited resonantly by femtosecond extreme-ultraviolet (XUV) pulses from a seeded free-electron laser. Despite their superfluid nature, we find that helium nanodroplets in the lowest electronically excited states undergo ultrafast relaxation. By comparing experimental photoelectron spectra with time-dependent density functional theory simulations, we unravel the full relaxation pathway: Following an ultrafast interband transition, a void nanometer-sized bubble forms around the localized excitation (He$${}^{* }$$

*

) within 1 ps. Subsequently, the bubble collapses and releases metastable He$${}^{* }$$

*

at the droplet surface. This study highlights the high level of detail achievable in probing the photodynamics of nanosystems using tunable XUV pulses.
Differential expansion of T central memory precursor and effector subsets is regulated by division speed
Authors: Kretschmer Lorenz , Flossdorf Michael , Mir Jonas , Cho Yi-Li , Plambeck Marten , Treise Irina , Toska Albulena , Heinzel Susanne , Schiemann Matthias , Busch Dirk H. , Buchholz Veit R. 
Published: January 2020

AbstractWhile antigen-primed T cells proliferate at speeds close to the physiologic maximum of mammalian cells, T cell memory is maintained in the absence of antigen by rare cell divisions. The transition between these distinct proliferative programs has been difficult to resolve via population-based analyses. Here, we computationally reconstruct the proliferative history of single CD8+ T cells upon vaccination and measure the division speed of emerging T cell subsets in vivo. We find that slower cycling central memory precursors, characterized by an elongated G1 phase, segregate early from the bulk of rapidly dividing effector subsets, and further slow-down their cell cycle upon premature removal of antigenic stimuli. In contrast, curtailed availability of inflammatory stimuli selectively restrains effector T cell proliferation due to reduced receptivity for interleukin-2. In line with these findings, persistence of antigenic but not inflammatory stimuli throughout clonal expansion critically determines the later size of the memory compartment.
Forest management in southern China generates short term extensive carbon sequestration
Authors: Tong Xiaowei , Brandt Martin , Yue Yuemin , Ciais Philippe , Rudbeck Jepsen Martin , Penuelas Josep , Wigneron Jean-Pierre , Xiao Xiangming , Song Xiao-Peng , Horion Stephanie , Rasmussen Kjeld , Saatchi Sassan , Fan Lei , Wang Kelin , Zhang Bing , Chen Zhengchao , Wang Yuhang , Li Xiaojun , Fensholt Rasmus 
Published: January 2020

AbstractLand use policies have turned southern China into one of the most intensively managed forest regions in the world, with actions maximizing forest cover on soils with marginal agricultural potential while concurrently increasing livelihoods and mitigating climate change. Based on satellite observations, here we show that diverse land use changes in southern China have increased standing aboveground carbon stocks by 0.11 ± 0.05 Pg C y−1 during 2002–2017. Most of this regional carbon sink was contributed by newly established forests (32%), while forests already existing contributed 24%. Forest growth in harvested forest areas contributed 16% and non-forest areas contributed 28% to the carbon sink, while timber harvest was tripled. Soil moisture declined significantly in 8% of the area. We demonstrate that land management in southern China has been removing an amount of carbon equivalent to 33% of regional fossil CO2 emissions during the last 6 years, but forest growth saturation, land competition for food production and soil-water depletion challenge the longevity of this carbon sink service.
The mechanistic and functional profile of the therapeutic anti-IgE antibody ligelizumab differs from omalizumab
Authors: Gasser Pascal , Tarchevskaya Svetlana S. , Guntern Pascal , Brigger Daniel , Ruppli Rahel , Zbären Noemi , Kleinboelting Silke , Heusser Christoph , Jardetzky Theodore S. , Eggel Alexander 
Published: January 2020

AbstractTargeting of immunoglobulin E (IgE) represents an interesting approach for the treatment of allergic disorders. A high-affinity monoclonal anti-IgE antibody, ligelizumab, has recently been developed to overcome some of the limitations associated with the clinical use of the therapeutic anti-IgE antibody, omalizumab. Here, we determine the molecular binding profile and functional modes-of-action of ligelizumab. We solve the crystal structure of ligelizumab bound to IgE, and report epitope differences between ligelizumab and omalizumab that contribute to their qualitatively distinct IgE-receptor inhibition profiles. While ligelizumab shows superior inhibition of IgE binding to FcεRI, basophil activation, IgE production by B cells and passive systemic anaphylaxis in an in vivo mouse model, ligelizumab is less potent in inhibiting IgE:CD23 interactions than omalizumab. Our data thus provide a structural and mechanistic foundation for understanding the efficient suppression of FcεRI-dependent allergic reactions by ligelizumab in vitro as well as in vivo.
Global warming changes tropical cyclone translation speed
Authors: Yamaguchi Munehiko , Chan Johnny C. L. , Moon Il-Ju , Yoshida Kohei , Mizuta Ryo 
Published: January 2020

AbstractSlow-moving tropical cyclones (TCs) can cause heavy rain because of their duration of influence. Combined with expected increase in rain rates associated with TCs in a warmer climate, there is growing interest in TC translation speed in the past and future. Here we present that a slowdown trend of the translation speed is not simulated for the period 1951–2011 based on historical model simulations. We also find that the annual-mean translation speed could increase under global warming. Although previous studies show large uncertainties in the future projections of TC characteristics, our model simulations show that the average TC translation speed at higher latitudes becomes smaller in a warmer climate, but the relative frequency of TCs at higher latitudes increases. Since the translation speed is much larger in the extratropics, the increase in the relative frequency of TCs at higher latitudes compensates the reduction of the translation speed there, leading to a global mean increase in TC translation speed.
ULK1 phosphorylates Exo70 to suppress breast cancer metastasis
Authors: Mao Liyuan , Zhan Yan-yan , Wu Bin , Yu Qiang , Xu Liang , Hong Xiaoting , Zhong Linhai , Mi Panying , Xiao Li , Wang Xinquan , Cao Hanwei , Zhang Wenqing , Chen Binbin , Xiang Jingzhou , Mei Kunrong , Radhakrishnan Ravi , Guo Wei , Hu Tianhui 
Published: January 2020

AbstractIncreased expression of protein kinase ULK1 was reported to negatively correlate with breast cancer metastasis. Here we report that ULK1 suppresses the migration and invasion of human breast cancer cells. The suppressive effect is mediated through direct phosphorylation of Exo70, a key component of the exocyst complex. ULK1 phosphorylation inhibits Exo70 homo-oligomerization as well as its assembly to the exocyst complex, which are needed for cell protrusion formation and matrix metalloproteinases secretion during cell invasion. Reversely, upon growth factor stimulation, Exo70 is phosphorylated by ERK1/2, which in turn suppresses its phosphorylation by ULK1. Together, our study identifies Exo70 as a substrate of ULK1 that inhibits cancer metastasis, and demonstrates that two counteractive regulatory mechanisms are well orchestrated during tumor cell invasion.
Dopamine transients do not act as model-free prediction errors during associative learning
Authors: Sharpe Melissa J. , Batchelor Hannah M. , Mueller Lauren E. , Yun Chang Chun , Maes Etienne J. P. , Niv Yael , Schoenbaum Geoffrey 
Published: January 2020

AbstractDopamine neurons are proposed to signal the reward prediction error in model-free reinforcement learning algorithms. This term represents the unpredicted or ‘excess’ value of the rewarding event, value that is then added to the intrinsic value of any antecedent cues, contexts or events. To support this proposal, proponents cite evidence that artificially-induced dopamine transients cause lasting changes in behavior. Yet these studies do not generally assess learning under conditions where an endogenous prediction error would occur. Here, to address this, we conducted three experiments where we optogenetically activated dopamine neurons while rats were learning associative relationships, both with and without reward. In each experiment, the antecedent cues failed to acquire value and instead entered into associations with the later events, whether valueless cues or valued rewards. These results show that in learning situations appropriate for the appearance of a prediction error, dopamine transients support associative, rather than model-free, learning.
Soil bacterial diversity mediated by microscale aqueous-phase processes across biomes
Authors: Bickel Samuel , Or Dani 
Published: January 2020

AbstractSoil bacterial diversity varies across biomes with potential impacts on soil ecological functioning. Here, we incorporate key factors that affect soil bacterial abundance and diversity across spatial scales into a mechanistic modeling framework considering soil type, carbon inputs and climate towards predicting soil bacterial diversity. The soil aqueous-phase content and connectivity exert strong influence on bacterial diversity for each soil type and rainfall pattern. Biome-specific carbon inputs deduced from net primary productivity provide constraints on soil bacterial abundance independent from diversity. The proposed heuristic model captures observed global trends of bacterial diversity in good agreement with predictions by an individual-based mechanistic model. Bacterial diversity is highest at intermediate water contents where the aqueous phase forms numerous disconnected habitats and soil carrying capacity determines level of occupancy. The framework delineates global soil bacterial diversity hotspots; located mainly in climatic transition zones that are sensitive to potential climate and land use changes.
Topological magneto-optical effects and their quantization in noncoplanar antiferromagnets
Authors: Feng Wanxiang , Hanke Jan-Philipp , Zhou Xiaodong , Guo Guang-Yu , Blügel Stefan , Mokrousov Yuriy , Yao Yugui 
Published: January 2020

AbstractReflecting the fundamental interactions of polarized light with magnetic matter, magneto-optical effects are well known since more than a century. The emergence of these phenomena is commonly attributed to the interplay between exchange splitting and spin-orbit coupling in the electronic structure of magnets. Using theoretical arguments, we demonstrate that topological magneto-optical effects can arise in noncoplanar antiferromagnets due to the finite scalar spin chirality, without any reference to exchange splitting or spin-orbit coupling. We propose spectral integrals of certain magneto-optical quantities that uncover the unique topological nature of the discovered effect. We also find that the Kerr and Faraday rotation angles can be quantized in insulating topological antiferromagnets in the low-frequency limit, owing to nontrivial global properties that manifest in quantum topological magneto-optical effects. Although the predicted topological and quantum topological magneto-optical effects are fundamentally distinct from conventional light-matter interactions, they can be measured by readily available experimental techniques.