bluuebunny/crossref_metadata_2025 huggingface dataset:
GEOTHERMAL ENERGY OF THE REPUBLIC OF SRPSKA AND HYDROCHEMICAL ASPECTS OF ITS EXPLORATION AND EXPLOITATION
Authors: Stevanović Andrijana , Jolović Boban
Published: January 2018

One of the most used renewable energy sources worldwide is geothermal energy. Itrepresents the heat, originated by natural processes happen in the Earth interior. The hot springsphenomena are the most frequent natural manifestation of geothermal activity.Geothermal potentiality of some area can be estimated based on geothermal gradient. Geothermalgradient is a conductive terrestrial parameter that represents the degree of increasing of the Earthtemperature vs. depth. It is usually expressed in ⁰C/m or ⁰C/km. Different areas have differentthermal gradients and thus different geothermal potential. Generally, higher geothermal gradientscorrespond to areas containing more geothermal energy.Geothermal characteristics of the territory of the Republic of Srpska are closely related to itscomplex geological setting. It is the reason why geothermal characteristics are different from areato area. Higher geothermal potentiality is recognised in the northern parts of the entity, in the firstorder in Semberija, Posavina and Banja Luka regions.The use of geothermal energy with different fluid temperatures can be considered throughthe Lindaldiagram, who firstly proposed acomprehensive scale with appropriate temperatures for differentuses. High temperature fluids are mostly used for electricity production and moderate and lowtemperature fluids for the direct use.Despite the fact that the territory of the Republic of Srpska hasfavourable geothermal properties, utilization of this kind of renewable energy resource isinadequate. Especially indicative are data about the use of geothermal energy by heat pumps (inbad sense) in comparison with praxis of developed countries.Chemical composition of thermal waters plays very important role and can be used in itsexploration stage, for analyses of possibility of its use and for prediction of exploitation effects, aswell. This kind of renewable energyresource, highly ecologically recommended, must be consideredmore seriously in the future in the Republic of Srpska. Furthermore, it must be put into the energystrategic documentsin appropriate manner.
INFLUENCE OF DOUBLE SOLUTION TREATMENT ON HARDNESS IN 17-4 PH STEEL
Authors: Sowa R. , Arabasz S. , Roga E. , Dziedzic A. , Dul I. , Kowal A. , Parlinska-Wojtan M.
Published: January 2018

The investigated material is a corrosion-resistant, Cu precipitation hardened steel 17-4PH,which undergoes a macroscopic contraction, as a result of applying the following heat treatment:double solution treatment at 1028°C for 1 h (condition A), ageing at 540°C for 4 h (conditionH1025). The second solution treatment at 1028°C was found to eliminate the retained austenite,being the evidence of a completely finished martensitic transformation.Indeed, the only phaseidentified in all samples was fcc lath martensite exhibiting a parallel striped structure.Unfortunately, this additional heat-treatment operation leads likewise to significant and irregulargrain growth, which consequently causes a drop in material hardness. Moreover, the secondsolution annealing, caused a shift in the XRD peaks to higher 2θ angles, resulting from a latticeparameter decrease by0,25%. The two subsequent heat-treatment procedures bring the latticeparameter back to its initial value. This seemingly reversible process of decrease and increase of thelattice parameter was observed for samples subjected to all the heat treatment operations, stronglysuggesting the existence of a relation between the microstructural changes and the macroscopiccontraction of the steel material. In addition to the martensitic phase, in the unaged samples, a δ-ferrite phase could be identified by TEM and electron diffraction, which is favorable for ductilityand toughness of the material. In all samples, non-coherent fcc-NbC precipitates identified byelectron diffraction and EDX mapping having sizes up to 70 nm were found.
ALERGENI U HRANI – PRISUSTVO, RIZICI I UPRAVLJANJE U PREHRAMBENOJ INDUSTRIJI
Authors: Grujić Radoslav
Published: January 2018

Alergija na hranu predstavlja reakciju imunog sistema organizma na prisustvo proteinaunešenih u organizam preko hrane. Alergijske reakcije mogu uticati na kožu (koprivnjače),gastrointestinalne organe (muka, grčevi, dijareja), disajne organe (gušenje) i cirkulaciju (padkrvnog pritiska). U ekstremnim slučajevima može se pojaviti i anafilaksija. U tom slučaju smrt moženastupiti za nekoliko minuta. Alergeni u hrani su prirodni proteini koji su otporni na djelovanjetoplote, proteolitičkih enzima i promjenu pH. Imuni sistem pojedinca može da reaguje na veomamalu količinu prisutnih alergena (količina izraženu u ppm). Različite individue su različito osjetljivei specifično reaguju na prisustvo istog alergena. Izbegavanje kontakta sa alergenom je jedini putkojim alergična osoba može spriječiti reakciju. Prema procjenama, 2-4% od ukupnog brojastanovništva u Evropi, 4-8% djece i 1-2% odraslih stanovnika u SAD je alergično na hranu.Alergijske reakcije na hranu u SAD su uzrok 150-200 smrtnih slučajeva godišnje. Smanjenje rizikana elergene iz hrane sa kojim se suočavaju potrošači može se smanjiti: pravovremenimidentifikovanjem prehrambenih proizvoda koji sadrže materije izazivače alergijskih reakcija,adekvatnom kontrolom u procesu proizvodnje i skladištenja hrane (GMP, HACCP) i korištenjemalatki koje mogu verifikovati provedenu kontrolu (propisi, označavanje).
La efectividad de las campañas de comunicación anti-tabaco en los jóvenes españoles. Un análisis exploratorio
Authors: Vázquez Burguete José Luis , Gutiérrez Rodríguez Pablo , Cuesta Valiño Pedro , García Miguélez María Purificación
Published: January 2018

Despite the growing use of commercial communication in different economic sectors, literature still has certain theoretical and practical gaps. These gaps are produced because there still exists a lack of information about which variables are those that make up commercial communication as well as which of those variables is the most effective. With an exploratory approach, our article tries to fill the gaps through research in the public university education sector. The results validate some of the hypotheses raised and show that some variables are more effective than others. At the same time, that the influence of commercial communication on purchasing is not direct but that it should be thought of as the intervention of variables which are of a subjective nature. In this way, our study contributes to literature in as much as it demonstrates that commercial communication can be used in non-profitable sectors which have very specific restrictions when using communication variables.
Estrategia de creación de un sello de calidad: Canarias destino familias
Authors: García Henche Blanca , Mielgo Álvarez Arancha , Reinares Lara Eva Marina , Saco Vázquez Manuela
Published: January 2018

This article is part of more extensive research which has as a final objective the creation and commercialization of a Seal of Quality for tourist destinations. Since the beginning of the 1990´s, the Spanish tourist sector has carried out different initiatives with a common goal – to improve quality. The latest aim of an Integrated Quality System in all the subsectors of the tourist industry is to create seals of quality guarantee which generate a new image of Tourist Quality. This allows the promoting of quality destinations as well as the adapting of these to the tourist´s profile in addition to developing business administrative tools to improve consumer satisfaction. In this context, a seal of quality indicative of specific services which serve to qualify and distinguish the Canary Islands as an adequate family tourist destination has been proposed. The theoretical framework of this work is centered on the strategies of creating seals or labels and their objectives. From the perspective of offer, as common generic objectives, it is worth noting that it is an instrument of protection, promotion, and commercialization. With regards to demand, it is considered an important source of information and meaning for the target customers. From these objectives, the specific performance areas which are covered by the research done refer to: the definition of the seal for the users, the analysis of the recipients, the identification of the advantages of the seal for the users/tourists and for the enterprises/institutions and the drawing-up of the requisites that the establishments and organisms belonging to this seal should meet. To reach these goals secondary sources as well as primary sources have been used from personal surveys carried out on family units.
Efectos de la promoción de ventas en el largo plazo en Marcas de Fabricante y Marcas de Distribución en la categoría de bebidas energéticas
Authors: Alard Josemaría Julio , Marín Palacios Cristina , Cubillo Pinilla José María
Published: January 2018

In this research, the authors analyze the different types of promotion used by National Brand and Private Label and the long-run effects on sales on both categories. The analysis focusses on the promotional activity undertaken by the leading brands of energy drinks that operate in the domestic market. The survey, based on scanner data al store-level in a series which covers 7 years, provides almost all of the history of the category. In this sub-segment of beverages, there have been significant increases in sales in recent years and the brands managed by the retailer has to more than half the market share in the super and hyper channels, overcoming the volume from leading brand in 2004. However the study shows that the effect of promotions in the category in question is less intense in the Private Label than in the National Brand, and that not all the promotion types tested have the same effect, being the display and feature that have an impact higher sales.
Marcas de la distribución. Denominación y definición para una comunicación más precisa
Authors: Yustas López Yolanda , Requena Laviña María
Published: January 2018

This article reviews the main literary contributions on the various names and concepts of distribution brands to see if it is possible to establish a definition that encompasses all of these label types and create a single term with which to call them. In doing this, the communication carried out by different social agents (researchers, brand managers, and mass media) of the brands would be more accurate, as it would then be clear if the information conveyed referred to all the brands or just to some of them. The review of the literature includes references from Spanish authors and other, mainly English-speaking countries, and covers an extensive period of time from the 60´s to the present day. The review also includes several different types of sources: books, journal articles, doctoral thesis and web pages among others. The article highlights the profusion of terms used by different authors to refer to distribution brands, the non-existence an equal relationship between each term used and the concept that it refers to. It highlights that sometimes two or more different terms are used to refer to the same concept, sometimes the same name is used to refer to two different concepts, and sometimes the same term is used to designate not only the global concept of distribution brands but also to designate specific types. It is therefore difficult to establish the most adequate term and definition for retail brands that wouldn’t cause confusion when dealing with information related to them. Nonetheless, after analyzing the terms and concepts from the literature, a name and a new definition for distribution brands is proposed and that could used in broad terms.
Pollination implications of the diverse diet of tropical nectar-feeding bats roosting in an urban cave
Authors: Lim Voon-Ching , Ramli Rosli , Bhassu Subha , Wilson John James
Published: January 2018

Background. Intense landscaping often alters the plant composition in urban areas. Knowing which plant species that pollinators are visiting in urban areas is necessary for understanding how landscaping impacts biodiversity and associated ecosystem services. The cave nectar bat, Eonycteris spelaea, is an important pollinator for many plants and is often recorded in human-dominated habitats. Previous studies of the diet of E. spelaea relied on morphological identification of pollen grains found in faeces and on the body of bats and by necessity disregarded other forms of digested plant material present in the faeces (i.e., plant juice and remnants). The main objective of this study was to examine the diet of the nectarivorous bat, E. spelaea, roosting in an urban cave at Batu Caves, Peninsular Malaysia by identifying the plant material present in the faeces of bats using DNA metabarcoding.

Methods. Faeces were collected under the roost of E. spelaea once a week from December 2015 to March 2016. Plant DNA was extracted from the faeces, PCR amplified at ITS2 and rbcL regions and mass sequenced. The resultant plant OTU were searched against NCBI GenBank for identification.

Results. A total of 55 species of plants were detected from faeces of E. spelaea including Artocarpus heterophyllus, Duabanga grandiflora and Musa spp. which are likely to be important food resources for the cave nectar bat.

Discussion. Many native plant species that had not been reported in previous dietary studies of E. spelaea were detected in this study including Bauhinia strychnoidea and Urophyllum leucophlaeum, suggesting that E. spelaea remains a crucial pollinator for these plants even in highly disturbed habitats. The detection of many introduced plant species in the bat faeces indicates that E. spelaea are exploiting them, particularly Xanthostemon chrysanthus, as food resources in urban area. Commercial food crops were detected from all of the faecal samples, suggesting that E. spelaea feed predominantly on the crops particularly jackfruit and banana and play a significant role in pollination of economically important plants. Ferns and figs were also detected in the faeces of E. spelaea suggesting future research avenues to determine whether the “specialised nectarivorous” E. spelaea feed opportunistically on other parts of plants.
Neuronal activity determines distinct gliotransmitter release from a single astrocyte
Authors: Covelo Ana , Araque Alfonso
Published: January 2018

Accumulating evidence indicates that astrocytes are actively involved in brain function by regulating synaptic activity and plasticity. Different gliotransmitters, such as glutamate, ATP, GABA or D-serine, released form astrocytes have been shown to induce different forms of synaptic regulation. However, whether a single astrocyte may release different gliotransmitters is unknown. Here we show that mouse hippocampal astrocytes activated by endogenous (neuron-released endocannabinoids or GABA) or exogenous (single astrocyte Ca2+ uncaging) stimuli modulate putative single CA3-CA1 hippocampal synapses. The astrocyte-mediated synaptic modulation was biphasic and consisted of an initial glutamate-mediated potentiation followed by a purinergic-mediated depression of neurotransmitter release. The temporal dynamic properties of this biphasic synaptic regulation depended on the firing frequency and duration of the neuronal activity that stimulated astrocytes. Present results indicate that single astrocytes can decode neuronal activity and, in response, release distinct gliotransmitters to differentially regulate neurotransmission at putative single synapses.
COX16 promotes COX2 metallation and assembly during respiratory complex IV biogenesis
Authors: Aich Abhishek , Wang Cong , Chowdhury Arpita , Ronsör Christin , Pacheu-Grau David , Richter-Dennerlein Ricarda , Dennerlein Sven , Rehling Peter
Published: January 2018

Cytochrome c oxidase of the mitochondrial oxidative phosphorylation system reduces molecular oxygen with redox equivalent-derived electrons. The conserved mitochondrial-encoded COX1- and COX2-subunits are the heme- and copper-center containing core subunits that catalyze water formation. COX1 and COX2 initially follow independent biogenesis pathways creating assembly modules with subunit-specific, chaperone-like assembly factors that assist in redox centers formation. Here, we find that COX16, a protein required for cytochrome c oxidase assembly, interacts specifically with newly synthesized COX2 and its copper center-forming metallochaperones SCO1, SCO2, and COA6. The recruitment of SCO1 to the COX2-module is COX16- dependent and patient-mimicking mutations in SCO1 affect interaction with COX16. These findings implicate COX16 in CuA-site formation. Surprisingly, COX16 is also found in COX1-containing assembly intermediates and COX2 recruitment to COX1. We conclude that COX16 participates in merging the COX1 and COX2 assembly lines.
Multivesicular bodies mediate long-range retrograde NGF-TrkA signaling
Authors: Ye Mengchen , Lehigh Kathryn M , Ginty David D
Published: January 2018

The development of neurons in the peripheral nervous system is dependent on target-derived, long-range retrograde neurotrophic factor signals. The prevailing view is that target-derived nerve growth factor (NGF), the prototypical neurotrophin, and its receptor TrkA are carried retrogradely by early endosomes, which serve as TrkA signaling platforms in cell bodies. Here, we report that the majority of retrograde TrkA signaling endosomes in mouse sympathetic neurons are ultrastructurally and molecularly defined multivesicular bodies (MVBs). In contrast to MVBs that carry non-TrkA cargoes from distal axons to cell bodies, retrogradely transported TrkA+ MVBs that arrive in cell bodies evade lysosomal fusion and instead evolve into TrkA+ single-membrane vesicles that are signaling competent. Moreover, TrkA kinase activity associated with retrogradely transported TrkA+ MVBs determines TrkA+ endosome evolution and fate. Thus, MVBs deliver long-range retrograde NGF signals and serve as signaling and sorting platforms in the cell soma, and MVB cargoes dictate their vesicular fate.
Multiband and Miniaturized dual layer Antenna incorporated with FSS and DGS
Authors: Sah S. , Tripathy M. R. , Mittal A.
Published: January 2018

A novel dual  layer rectangular printed Antenna based on loop type Frequency selective surfaces with five concentric rings and I shaped defected ground structure (DGS) is designed and investigated. The deigned antenna is tested for application in C band, WiFi devices and some cordless telephones and X band radiolocation, airborne and naval radars as multiband  operational frequencies are at 5.5GHz, 6.81GHz, 9.3GHz and thus covers two wireless communication band C Band (4 to 8GHz ) and  X band (8 to 12 GHz) The bandwidth is 200MHz, 300MHz and 1GHz respectively and measured gain of this designed antenna are 2.42dBi against 5.5GHz, 2.80dBi against 6.81GHz, 6.76dBi against 9.3GHz. The proposed antenna in addition to multiband operation also exhibits minituarization.The Floquet port technique is used to analyse concentric rings. The Results comparison of proposed structure with the basic dual layer antenna resonaing at 5.5GHz  shows the patch area is reduced by 58.15% while the volume of the antenna is reduced by 81.5%.
Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection
Authors: Tan Wei-Lian , Lee Yean Kee , Ho Yen Fong , Yusof Rohana , Abdul Rahman Noorsaadah , Karsani Saiful Anuar
Published: January 2018

Dengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV) infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda) that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection.
Morphological Indicators of a Mascon Beneath Ceres's Largest Crater, Kerwan
Authors: Bland M. T. , Ermakov A. I. , Raymond C. A. , Williams D. A. , Bowling T. J. , Preusker F. , Park R. S. , Marchi S. , Castillo‐Rogez J. C. , Fu R. R. , Russell C. T.
Published: January 2018

Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long‐term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact‐induced uplift of the high‐density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest‐degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin‐associated gravity anomalies, although their origin may differ substantially.
Turbidity Currents With Equilibrium Basal Driving Layers: A Mechanism for Long Runout
Authors: Luchi R. , Balachandar S. , Seminara G. , Parker G.
Published: January 2018

Turbidity currents run out over 100 km in lakes and reservoirs, and over 1,000 km in the ocean. They do so without dissipating themselves via excess entrainment of ambient water. Existing layer‐averaged formulations cannot capture this. We use a numerical model to describe the temporal evolution of a turbidity current toward steady state under condition of zero net sediment flux at the bed. The flow self‐partitions itself into two layers. The lower “driving layer” approaches an invariant flow thickness, velocity profile, and suspended sediment concentration profile that sequesters nearly all of the suspended sediment. This layer can continue indefinitely at steady state over a constant bed slope. The upper “driven layer” contains a small fraction of the suspended sediment. The devolution of the flow into these two layers likely allows the driving layer to run out long distances.
Chemical Reactions Between Fe and H2O up to Megabar Pressures and Implications for Water Storage in the Earth's Mantle and Core
Authors: Yuan Liang , Ohtani Eiji , Ikuta Daijo , Kamada Seiji , Tsuchiya Jun , Naohisa Hirao , Ohishi Yasuo , Suzuki Akio
Published: January 2018

We investigated the phase relations of the Fe‐H2O system at high pressures based on in situ X‐ray diffraction experiments and first‐principles calculations and demonstrate that FeHxand FeO are present at pressures less than ~78 GPa. A recently reported pyrite‐structured FeO2was identified in the Fe‐H2O system at pressures greater than ~78 GPa after laser heating. The phase observed in this study has a unit cell volume 8%–11% larger than that of FeO2, produced in the Fe‐O binary system reported previously, suggesting that hydrogen might be retained in a FeO2Hxcrystal structure. Our observations indicate that H2O is likely introduced into the deep Earth through reaction between iron and water during the accretion and separation of the metallic core. Additionally, reaction between Fe and H2O would occur at the core‐mantle boundary, given water released from hydrous subducting slabs that intersect with the metallic core. Accumulation of volatile‐bearing iron compounds may provide new insights into the enigmatic seismic structures observed at the base of the lower mantle.
What Climate Sensitivity Index Is Most Useful for Projections?
Authors: Grose Michael R. , Gregory Jonathan , Colman Robert , Andrews Timothy
Published: January 2018

Transient climate response (TCR), transient response at 140 years (T140), and equilibrium climate sensitivity (ECS) indices are intended as benchmarks for comparing the magnitude of climate response projected by climate models. It is generally assumed that TCR or T140 would explain more variability between models than ECS for temperature change over the 21st century, since this timescale is the realm of transient climate change. Here we find that TCR explains more variability across Coupled Model Intercomparison Project phase 5 than ECS for global temperature change since preindustrial, for 50 or 100 year global trends up to the present, and for projected change under representative concentration pathways in regions of delayed warming such as the Southern Ocean. However, unexpectedly, we find that ECS correlates higher than TCR for projected change from the present in the global mean and in most regions. This higher correlation does not relate to aerosol forcing, and the physical cause requires further investigation.
Resonant Scattering of Radiation Belt Electrons by Off‐Equatorial Magnetosonic Waves
Authors: Ni Binbin , Zou Zhengyang , Fu Song , Cao Xing , Gu Xudong , Xiang Zheng
Published: January 2018

Fast magnetosonic (MS) waves are commonly regarded as electromagnetic waves that are characteristically confined within ±3° of the geomagnetic equator. We report two typical off‐equatorial MS events observed by Van Allen Probes, that is, the 8 May 2014 event that occurred at the geomagnetic latitudes of 7.5°–9.2° both inside and outside the plasmasphere with the wave amplitude up to 590 pT and the 9 January 2014 event that occurred at the latitudes of—(15.7°–17.5°) outside the plasmasphere with a smaller amplitude about 81 pT. Detailed test particle simulations quantify the electron resonant scattering rates by the off‐equatorial MS waves to find that they can cause the pitch angle scattering and momentum diffusion of radiation belt electrons with equatorial pitch angles < ~75° or < ~58° (depending on the wave latitudinal coverage) on timescales of a day. Subsequent two‐dimensional Fokker‐Planck diffusion simulations indicate that the strong off‐equatorial MS waves are capable of efficiently transporting high pitch angle electrons to lower pitch angles to facilitate the formation of radiation belt electron butterfly distributions for a broad energy range from ~100 keV to >1 MeV within an hour. Our study clearly demonstrates that the presence of off‐equatorial MS waves, in addition to equatorial MS waves, can contribute importantly to the dynamical variations of radiation belt electron fluxes and their pitch angle distribution.
Fault Zone Permeability Decrease Following Large Earthquakes in a Hydrothermal System
Authors: Shi Zheming , Zhang Shouchuan , Yan Rui , Wang Guangcai
Published: January 2018

Seismic wave shaking‐induced permeability enhancement in the shallow crust has been widely observed. Permeability decrease, however, is seldom reported. In this study, we document coseismic discharge and temperature decrease in a hot spring following the 1996 Lijiang Mw 7.0 and the 2004 Mw 9.0 earthquakes in the Balazhang geothermal field. We use three different models to constrain the permeability change and the mechanism of coseismic discharge decrease, and we use an end‐member mixing model for the coseismic temperature change. Our results show that the earthquake‐induced permeability decrease in the fault zone reduced the recharge from deep hot water, which may be the mechanism that explains the coseismic discharge and temperature responses. The changes in the hot spring response reflect the dynamic changes in the hydrothermal system; in the future, the earthquake‐induced permeability decrease should be considered when discussing controls on permeability.
Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity From Observations
Authors: Marvel Kate , Pincus Robert , Schmidt Gavin A. , Miller Ron L.
Published: January 2018

An emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979–2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2 radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long‐term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long‐term sensitivity.
Investigation of the Electron Density Variation During the 21 August 2017 Solar Eclipse
Authors: Reinisch B. W. , Dandenault P. B. , Galkin I. A. , Hamel R. , Richards P. G.
Published: January 2018

This paper presents a comparison of modeled and measured electron densities for the 21 August 2017 solar eclipse across the USA. The location of the instrument was (43.81°N, 247.32°E) where the maximum obscuration of 99.6% occurred at 17.53 hr UT on 21 August. The solar apparent time was 9.96 hr, and the duration of the eclipse was 2.7 hr. It was found that if it is assumed that there are no chromosphere emissions at totality, ~30% coronal emission remaining at totality gave the best fit to the electron density variation at 150 km. The 30% coronal emission estimate has uncertainties associated with respect to uncertainties in the solar spectrum, the measured electron density, and the amount of chromosphere emissions remaining at totality. The agreement between the modeled and measured electron densities is excellent at 150 km with the assumed 30% coronal emission at totality. At other altitudes, the agreement is very good, but the altitude profile would be improved if the model peak electron density (NmF2) decayed more slowly to better match the data. The minimum NmF2 in the model occurs ~10 min after totality when it decreases to 0.55 from its noneclipse value. The minimum of the NmF2 data occurs between 6 and 10 min after totality but is ~15% larger. The total electron content decreases to 0.65 of its preeclipse value. These relative changes agree well with those predicted by others prior to the eclipse.
A New Estimate of North American Mountain Snow Accumulation From Regional Climate Model Simulations
Authors: Wrzesien Melissa L. , Durand Michael T. , Pavelsky Tamlin M. , Kapnick Sarah B. , Zhang Yu , Guo Junyi , Shum C. K.
Published: January 2018

Despite the importance of mountain snowpack to understanding the water and energy cycles in North America's montane regions, no reliable mountain snow climatology exists for the entire continent. We present a new estimate of mountain snow water equivalent (SWE) for North America from regional climate model simulations. Climatological peak SWE in North America mountains is 1,006 km3, 2.94 times larger than previous estimates from reanalyses. By combining this mountain SWE value with the best available global product in nonmountain areas, we estimate peak North America SWE of 1,684 km3, 55% greater than previous estimates. In our simulations, the date of maximum SWE varies widely by mountain range, from early March to mid‐April. Though mountains comprise 24% of the continent's land area, we estimate that they contain ~60% of North American SWE. This new estimate is a suitable benchmark for continental‐ and global‐scale water and energy budget studies.
Sensitivity of Homogeneous Ice Nucleation to Aerosol Perturbations and Its Implications for Aerosol Indirect Effects Through Cirrus Clouds
Authors: Liu X. , Shi X.
Published: January 2018

The magnitude and sign of anthropogenic aerosol impacts on cirrus clouds through ice nucleation are still very uncertain. In this study, aerosol sensitivity (ηα), defined as the sensitivity of the number concentration (Ni) of ice crystals formed from homogeneous ice nucleation to aerosol number concentration (Na), is examined based on simulations from a cloud parcel model. The model represents the fundamental process of ice crystal formation that results from homogeneous nucleation. We find that the geometric dispersion (σ) of the aerosol size distribution used in the model is a key factor for ηα. For a monodisperse size distribution, ηα is close to zero in vertical updrafts (V < 50 cm s−1) typical of cirrus clouds. However, ηα increases to 0.1–0.3 (i.e., Ni increases by a factor of 1.3–2.0 for a tenfold increase in Na) if aerosol particles follow lognormal size distributions with a σ of 1.6–2.3 in the upper troposphere. By varying the input aerosol and environmental parameters, our model reproduces a large range of ηα values derived from homogeneous ice nucleation parameterizations widely used in global climate models (GCMs). The differences in ηα from these parameterizations can translate into a range of anthropogenic aerosol longwave indirect forcings through cirrus clouds from 0.05 to 0.36 W m−2 with a GCM. Our study suggests that a larger ηα (0.1–0.3) is more plausible and the homogeneous nucleation parameterizations should include a realistic aerosol size distribution to accurately quantify anthropogenic aerosol indirect effects.
Localized Oscillatory Energy Conversion in Magnetopause Reconnection
Authors: Burch J. L. , Ergun R. E. , Cassak P. A. , Webster J. M. , Torbert R. B. , Giles B. L. , Dorelli J. C. , Rager A. C. , Hwang K.‐J. , Phan T. D. , Genestreti K. J. , Allen R. C. , Chen L.‐J. , Wang S. , Gershman D. , Le Contel O. , Russell C. T. , Strangeway R. J. , Wilder F. D. , Graham D. B. , Hesse M. , Drake J. F. , Swisdak M. , Price L. M. , Shay M. A. , Lindqvist P.‐A. , Pollock C. J. , Denton R. E. , Newman D. L.
Published: January 2018

Data from the NASA Magnetospheric Multiscale mission are used to investigate asymmetric magnetic reconnection at the dayside boundary between the Earth's magnetosphere and the solar wind. High‐resolution measurements of plasmas and fields are used to identify highly localized (~15 electron Debye lengths) standing wave structures with large electric field amplitudes (up to 100 mV/m). These wave structures are associated with spatially oscillatory energy conversion, which appears as alternatingly positive and negative values of J · E. For small guide magnetic fields the wave structures occur in the electron stagnation region at the magnetosphere edge of the electron diffusion region. For larger guide fields the structures also occur near the reconnection X‐line. This difference is explained in terms of channels for the out‐of‐plane current (agyrotropic electrons at the stagnation point and guide field‐aligned electrons at the X‐line).
Pitch Angle Scattering of Upgoing Electron Beams in Jupiter's Polar Regions by Whistler Mode Waves
Authors: Elliott S. S. , Gurnett D. A. , Kurth W. S. , Clark G. , Mauk B. H. , Bolton S. J. , Connerney J. E. P. , Levin S. M.
Published: January 2018

The Juno spacecraft's Jupiter Energetic‐particle Detector Instrument has observed field‐aligned, unidirectional (upgoing) electron beams throughout most of Jupiter's entire polar cap region. The Waves instrument detected intense broadband whistler mode emissions occurring in the same region. In this paper, we investigate the pitch angle scattering of the upgoing electron beams due to interactions with the whistler mode waves. Profiles of intensity versus pitch angle for electron beams ranging from 2.53 to 7.22 Jovian radii show inconsistencies with the expected adiabatic invariant motion of the electrons. It is believed that the observed whistler mode waves perturb the electron motion and scatter them away from the magnetic field line. The diffusion equation has been solved by using diffusion coefficients which depend on the magnetic intensity of the whistler mode waves.
Fault Geometry and Slip Distribution at Depth of the 1997 Mw 7.2 Zirkuh Earthquake: Contribution of Near‐Field Displacement Data
Authors: Marchandon Mathilde , Vergnolle Mathilde , Sudhaus Henriette , Cavalié Olivier
Published: January 2018

In this study, we reestimate the source model of the 1997 Mw 7.2 Zirkuh earthquake (northeastern Iran) by jointly optimizing intermediate‐field Interferometry Synthetic Aperture Radar data and near‐field optical correlation data using a two‐step fault modeling procedure. First, we estimate the geometry of the multisegmented Abiz fault using a genetic algorithm. Then, we discretize the fault segments into subfaults and invert the data to image the slip distribution on the fault. Our joint‐data model, although similar to the Interferometry Synthetic Aperture Radar‐based model to the first order, highlights differences in the fault dip and slip distribution. Our preferred model is ∼80° west dipping in the northern part of the fault, ∼75° east dipping in the southern part and shows three disconnected high slip zones separated by low slip zones. The low slip zones are located where the Abiz fault shows geometric complexities and where the aftershocks are located. We interpret this rough slip distribution as three asperities separated by geometrical barriers that impede the rupture propagation. Finally, no shallow slip deficit is found for the overall rupture except on the central segment where it could be due to off‐fault deformation in quaternary deposits.
Dependence of the Onset of the Runaway Greenhouse Effect on the Latitudinal Surface Water Distribution of Earth‐Like Planets
Authors: Kodama T. , Nitta A. , Genda H. , Takao Y. , O'ishi R. , Abe‐Ouchi A. , Abe Y.
Published: January 2018

Liquid water is one of the most important materials affecting the climate and habitability of a terrestrial planet. Liquid water vaporizes entirely when planets receive insolation above a certain critical value, which is called the runaway greenhouse threshold. This threshold forms the inner most limit of the habitable zone. Here we investigate the effects of the distribution of surface water on the runaway greenhouse threshold for Earth‐sized planets using a three‐dimensional dynamic atmosphere model. We considered a 1 bar atmosphere whose composition is similar to the current Earth's atmosphere with a zonally uniform distribution of surface water. As previous studies have already showed, we also recognized two climate regimes: the land planet regime, which has dry low‐latitude and wet high‐latitude regions, and the aqua planet regime, which is globally wet. We showed that each regime is controlled by the width of the Hadley circulation, the amount of surface water, and the planetary topography. We found that the runaway greenhouse threshold varies continuously with the surface water distribution from about 130% (an aqua planet) to 180% (the extreme case of a land planet) of the present insolation at Earth's orbit. Our results indicate that the inner edge of the habitable zone is not a single sharp boundary, but a border whose location varies depending on planetary surface condition, such as the amount of surface water. Since land planets have wider habitable zones and less cloud cover, land planets would be good targets for future observations investigating planetary habitability.
Trends and Variability in Temperature Sensitivity of Lilac Flowering Phenology
Authors: Wang Huanjiong , Dai Junhu , Rutishauser This , Gonsamo Alemu , Wu Chaoyang , Ge Quansheng
Published: January 2018

The responses of plant phenology to temperature variability have many consequences for ecological processes, agriculture, forestry, and human health. Temperature sensitivity (ST) of phenology could measure how and to what degree plant could phenologically track climate change. The long‐term trends and spatial patterns in ST have been well studied for vegetative phenology such as leaf unfolding, but trends to be expected for reproductive phenology in the future remain unknown. Here we investigate trends and factors driving the temporal variation of ST of first bloom date (FBD). Using the long‐term FBD records during 1963–2013 for common lilac (Syringa vulgaris) from 613 stations in Europe, we compared changes in ST from the beginning to the end of the study period. The Spearman partial correlations were used to assess the importance of four influencing factors. The results showed that the temporal changes in ST of FBD varied considerably among time scales. Mean ST decreased significantly by 0.92 days °C−1 from 1963–1972 to 2004–2013 (P < 0.01), but remained stable from 1963–1987 to 1989–2013. The strength of FBD and temperature relationship, the spring temperature variance, and winter chill all impact ST in an expected way at most stations. No consistent responses of ST on photoperiod were found. Our results imply that the trends and variability in ST of flowering phenology are driving by multiple factors and impacted by time scales. Continued efforts are still needed to further examine the flowering‐temperature relationship for other plant species in other climates and environments using similar methods to our study.
Subduction Evolution of the Dinarides and the Cretaceous Orogeny in the Eastern Alps: Hints From a New Paleotectonic Interpretation
Authors: Argnani A.
Published: January 2018

The geological evolution of the Dinarides and Eastern Alps is reconsidered taking into account the constraints from a new paleotectonic interpretation for the central Mediterranean. The geological record of the Dinarides suggests that more than one ocean existed between Africa and Europe in Late Triassic‐Late Jurassic. Besides the large Vardar ocean, it is inferred that the basin located to the west of the Pelagonian domain is floored by oceanic‐like lithosphere. Following the Late Jurassic‐Early Cretaceous westward obduction of the Vardar ophiolite onto Pelagonia, subduction resumed close to the European margin and continued until early Paleogene, when the Vardar oceanic basin was consumed. Subsequently, the substrate of the narrow Pindos ocean‐like basin was subducted to the east, accommodating a few hundreds of kilometers of Adria‐Eurasia convergence. Plate kinematics indicate that N‐S convergence between Africa and Europe initiated only after the Cenomanian, well after ophiolite obduction occurred in the Dinarides‐Hellenides. In the Eastern Alps, however, an early Late Cretaceous orogeny has been recorded, separated from the tectonic evolution of the Alps sensu strictu. This Cretaceous orogeny of the Eastern Alps has not been fully understood. The new reconstructions suggest that the Pindos and Vardar oceans merged north of Pelagonia and were confined by a transform fault bounding to the south the Austroalpine domain. Within this frame, where the occurrence of wider oceanic domains is considered, the Cretaceous orogeny of the Eastern Alps can be linked to different episodes of ophiolite obduction and a subsequent shift of tectonic activity that has been recorded in the Dinarides.
Brain atrophy and disability worsening in primary progressive multiple sclerosis: insights from the INFORMS study
Authors: Miller David H. , Lublin Fred D. , Sormani Maria Pia , Kappos Ludwig , Yaldizli Özgür , Freedman Mark S. , Cree Bruce A. C. , Weiner Howard L. , Lubetzki Catherine , Hartung Hans‐Peter , Montalban Xavier , Uitdehaag Bernard M. J. , MacManus David G. , Yousry Tarek A. , Gandini Wheeler‐Kingshott Claudia A. M. , Li Bingbing , Putzki Norman , Merschhemke Martin , Häring Dieter A. , Wolinsky Jerry S.
Published: January 2018

Objective

To investigate the relationship between brain volume and disability worsening over ≥3 years in the natural history of primary progressive multiple sclerosis using data from the placebo group of the INFORMS trial (n = 487; clinicaltrials.gov NCT00731692).

Methods

Magnetic resonance imaging scans were collected annually. Brain volume loss was determined using SIENA. Patients were stratified by baseline normalized brain volume after adjusting for demographic and disease‐burden covariates.

Results

Baseline normalized brain volume was predictive of disability worsening: Risk of 3‐month confirmed disability progression was reduced by 36% for high versus low baseline normalized brain volume (Cox's model hazard ratio 0.64, P = 0.0339; log‐rank test: P = 0.0297). Moreover, on‐study brain volume loss was significantly associated with disability worsening (P = 0.012) and was evident in patients with or without new lesions or relapses. Brain volume loss depended significantly on baseline T2 lesion volume (P < 0.0001). Despite low inflammatory activity at baseline (13% of patients had gadolinium‐enhancing lesions) and throughout the study (mean 0.5 new/enlarging T2 lesions and 172 mm3 T2 lesion volume increase per year), baseline T2 lesion volume was substantial (mean 10 cm3). Lower normalized brain volume at baseline correlated with higher baseline T2 volume and older age (both P < 0.0001).

Interpretation

Baseline brain volume and the rate of ongoing brain atrophy are significantly associated with disability worsening in primary progressive multiple sclerosis. Brain volume loss is significantly related to baseline T2 lesion volume, but partially independent of new lesion activity, which might explain the limited efficacy of anti‐inflammatory treatment.
Effects of background chewing sounds on learning: The role of misophonia sensitivity
Authors: Seaborne Amanda , Fiorella Logan
Published: January 2018

Misophonia refers to one's sensitivity to specific sounds, which can range from minor annoyance to extreme distress. This experiment tested the role of individual differences in misophonia sensitivity on learning. College students read a text passage about migraines in a quiet room with 2 or 3 other participants and 1 confederate. In some sessions, the confederate audibly chewed gum while reading the text (sound group); in other sessions, the confederate read silently (control group). All participants then completed a comprehension test on the material, followed by an assessment of their misophonia sensitivity. Although there was no overall difference between the two groups on the comprehension test, misophonia sensitivity significantly moderated the effect of the trigger sound on learning. Students who scored relatively high on misophonia sensitivity performed worse on the comprehension test if they were in the sound group but performed better if they were in the control group.