bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atmospheric discharges and particle fluxes
Authors: Chilingarian A. , Chilingaryan S. , Reymers A. 
Published: June 2015

AbstractFluxes of the electrons, gamma rays, and neutrons observed by particle detectors located on the Earth's surface during thunderstorms originate so‐called Thunderstorm Ground Enhancements (TGEs). The relativistic runaway electron avalanches giving rise to TGEs originate in the thundercloud's lower dipole between the main negatively charged region in the middle of the thundercloud and transient lower positively charged region. Acceleration of electrons in the upper dipole between main negative and main positive charge regions leads to initiation of the terrestrial gamma flashes (TGFs) intensive researched during the last two decades by orbiting gamma ray observatories. TGFs are exceptionally intense, submillisecond bursts of electromagnetic radiation directed to the open space from the thunderstorm atmosphere. Unlike visible lightning, TGF beams do not create a hot plasma channel and optical flash; hence, in the literature they got name “dark lightning.” We investigate the TGEs development in 1 min and 1 s time series of particle detector count rates. Synchronized time series of the near‐surface electric field and lightning occurrences allows interconnecting two atmospheric phenomena. Registration of the Extensive Air Showers allows approaching problems of relation of the lightning occurrences and particle fluxes.
Studies of the ionospheric turbulence excited by the fourth gyroharmonic at HAARP
Authors: Najmi A. , Milikh G. , Yampolski Y. M. , Koloskov A. V. , Sopin A. A. , Zalizovski A. , Bernhardt P. , Briczinski S. , Siefring C. , Chiang K. , Morton Y. , Taylor S. , Mahmoudian A. , Bristow W. , Ruohoniemi M. , Papadopoulos K. 
Published: June 2015

AbstractA study is presented of artificial ionospheric turbulence (AIT) induced by HF heating at High Frequency Active Auroral Research Program (HAARP) using frequencies close to the fourth electron gyroharmonic, in a broad range of radiated powers and using a number of different diagnostics. The diagnostics include GPS scintillations, ground‐based stimulated electromagnetic emission (SEE), the HAARP ionosonde, Kodiak radar, and signals received at the Ukrainian Antarctic Station (UAS). The latter allowed analysis of waves scattered by the AIT into the ionospheric waveguide along Earth's terminator, 15.6 mm from the HAARP facility. For the first time, the amplitudes of two prominent SEE features, the downshifted maximum and broad upshifted maximum, were observed to saturate at ~50% of the maximum HAARP effective radiated power. Nonlinear effects in slant total electron content, SEE, and signals received at UAS at different transmitted frequencies and intensities of the pump wave were observed. The correlations between the data from different detectors demonstrate that the scattered waves reach UAS by the waveguide along the Earth's terminator, and that they were injected into the waveguide by scattering off of artificial striations produced by AIT above HAARP, rather than via direct injection from sidelobe radiation.
Classifying onset durations of early VLF events: Scattered field analysis and new insights
Authors: Kotovsky D. A. , Moore R. C. 
Published: June 2015

AbstractThe physical processes responsible for a variety of early VLF scattering events have not yet been satisfactorily identified. Properly categorizing the early VLF event type is imperative to understand the causative physical processes involved. In this paper, the onset durations of 26 exceptionally high signal‐to‐noise ratio early VLF scattering events are analyzed, using scattered fields to classify events. New observations of events that exhibit “slow” amplitude changes, but “fast” scattered field changes are presented, which call into question previous analyses of early/slow events. We separately identify and analyze three early VLF events that definitively exhibit slow scattered field behavior. Additionally, we identify a significant number of events which have onset durations between the current definitions of fast and slow. Four events are observed which unambiguously exhibit a rapid initial rotation of the scattered field phasor during the first few seconds of the recovery stage. Possible physical mechanisms are discussed.
Late Tertiary reorganizations of deformation in northeastern Tibet constrained by stratigraphy and provenance data from eastern Longzhong Basin
Authors: Liu Shanpin , Li Jijun , Stockli Daniel F. , Song Chunhui , Nie Junsheng , Peng Tingjiang , Wang Xiuxi , He Kuang , Hui Zhengchuang , Zhang Jun 
Published: June 2015

AbstractThe deformation of the Tibetan Plateau is central to unraveling the process and mechanism of continental tectonics. Although most agree that crust shortening and plateau growth were protracted throughout the Cenozoic Indo‐Asian collision, particular deformation histories relating to tectonic kinematics and dynamics are still incomplete due to sparseness of diagnostic geological information from plateau margin. Here we present combined investigation of stratigraphy, magnetostratigraphy, and provenance for the eastern margin of Longzhong Basin to show two reorganizations of basin formation and tectonic regime during the late Tertiary. First, the depocenter migrated from the dispersed Paleogene sequences to the Wushan‐Tianshui foreland sequence during the earliest Miocene (circa 22 Ma), accompanied by shift of sedimentary provenance from double sources including the eastern Qilian block and eastern West Qinling terrain to single source within the West Qinling. It suggests reorganization of deformation from NW‐SE extension to NE‐SW contraction and initial uplift of the eastern West Qinling. Second, massive coarse‐grained fluvial beds were revived in the Wushan Basin during the late Miocene (circa 10 Ma), associated by eastward depositional expansion and another shift of sedimentary provenance toward northeast. It reflects thrusting up of the northern edge of the West Qinling and Liupan Shan Mountains linked with relocation of crust shortening from NE‐SW direction to ENE‐WSW direction and accelerated deformation of northeastern Tibet. These transitions of deformation regimes imply variation of geodynamic mechanisms during the process of plateau growth.
Magnetic mineral diagenesis in the river‐dominated inner shelf of the East China Sea, China
Authors: Ge Can , Zhang Weiguo , Dong Chenyin , Dong Yan , Bai Xuexin , Liu Jinyan , Hien Nguyen Thi Thu , Feng Huan , Yu Lizhong 
Published: June 2015

AbstractThe inner shelf of the East China Sea is a river‐dominated margin characterized by fine‐grained mud deposits and a rapid sedimentation rate. Three short sediment cores (~2.7 m in length) were examined to characterize spatial variations in magnetic mineral diagenesis. The sediment cores were analyzed for sedimentation rates, magnetic properties, particle size distribution, organic carbon, and total sulfur content. The two more proximal cores with higher sedimentation rates (~2.2 cm/yr and ~0.96 cm/yr) do not exhibit obvious effects of reductive dissolution of magnetite with increasing depth, which is consistent with their lower total sulfur content. The offshore core, A12‐4, which has a lower sedimentation rate, contains clear evidence of magnetite dissolution and increasing total sulfur content with depth. The three cores have a similar sediment source and organic matter input; therefore, we suggest that a higher sedimentation rate will lead to less reductive diagenesis of magnetite, assuming that other factors are constant. The iron‐ to sulfate‐reduction boundary, i.e., revealed by the onset of a rapid decline of magnetic susceptibility, is located 1.0 m below seafloor in core A12‐4. This is much deeper than is reported in many other coastal marine environments and can be explained by the higher sedimentation rate, the presence of refractory terrestrial organic matter, and an abundant input of detrital iron oxides. This study demonstrates that analyses of the magnetic mineral zonation provide a straightforward approach to assess diagenetic organic carbon decomposition pathways in marine environments.
Striping noise mitigation in ATMS brightness temperatures and its impact on cloud LWP retrievals
Authors: Ma Yuan , Zou Xiaolei 
Published: June 2015

AbstractAdvanced Technology Microwave Sounder (ATMS) on board Suomi National Polar‐orbiting Partnership (NPP) satellite provides global distributions of microwave brightness temperature measurements at 22 temperature and humidity sounding channels twice daily. However, the differences between observations and brightness temperature simulations exhibit a systematic along‐track striping noise for all channels. In this study, a set of 22 “optimal” filters is designed to remove the striping noise in different channels. It is shown that the original method for ATMS striping noise mitigation developed by Qin et al. () can be simplified and made suitable for use in an operational context. Impacts of striping noise mitigation on small‐scale weather features are investigated by comparing ATMS cloud liquid water path (LWP) retrieved before and after striping noise mitigation. It is shown that the optimal filters do not affect small‐scale cloud features while smoothing out striping noise in brightness temperatures. It is also shown that the striping noise is present in the LWP retrievals if the striping noise in brightness temperatures of ATMS channels 1 and 2 is not removed. The amplitude of the striping noise in LWP is linearly related to the magnitude of striping noise in ATMS brightness temperature observations.
Characteristics of submicron particulate matter at the urban roadside in downtown Hong Kong—Overview of 4 months of continuous high‐resolution aerosol mass spectrometer measurements
Authors: Lee Berto P. , Li Yong Jie , Yu Jian Zhen , Louie Peter K. K. , Chan Chak K. 
Published: June 2015

AbstractHong Kong, one of the world's most densely populated cities and an international financial center, has been suffering from traffic‐related air pollution. This study presents the first real‐time high‐resolution aerosol mass spectrometry measurements of submicron nonrefractory particulate matter (NR‐PM1) at the urban roadside in Hong Kong from March to July 2013 with the aim to identify major sources, to assess local and nonlocal emissions, and to characterize trends at different time scales. Organics were dominant, with fresh primary organic aerosol representing two thirds of the total measured organics. Cooking contributions in organic aerosol were assessed directly for the first time in Hong Kong and exceeded those related to vehicles although traffic was still the major PM1 source when elemental carbon was included. These findings were supported by additional measurements including traffic data, elemental/organic carbon, and VOC data. Springtime concentrations were about double of those in summer, due to a strong seasonal transition which affected meteorological conditions and street‐level circulation. Local formation of secondary species was not clearly discernible in either season. The elemental composition of organic aerosol remained stable with similar elemental ratios across the covered seasons: OM/OC: 1.49 ± 0.13, O/C: 0.25 ± 0.10, H/C: 1.68 ± 0.08 for spring and OM/OC: 1.43 ± 0.14, O/C: 0.21 ± 0.11, H/C: 1.69 ± 0.08 for summer. Diurnal changes in H/C and O/C as a result of mixing of primary organic aerosol and secondary organic aerosol were evident in the van Krevelen plot.
On the significance of the interannual relationship between the Asian‐Pacific Oscillation and the North Atlantic Oscillation
Authors: Zhou Botao , Wang Zunya 
Published: June 2015

AbstractUsing monthly data from the European Centre for Medium‐Range Weather Forecasts 40 year Re‐Analysis, this study investigated the interannual relationship between the Asian‐Pacific Oscillation (APO) and the North Atlantic Oscillation (NAO) for the period of May to August. The NAO is represented by the leading Empirical Orthogonal Function of sea level pressure anomalies over the Atlantic sector. The difference of upper tropospheric eddy air temperature (T′) between Asia and the North Pacific is used to measure the APO. Results clearly show that the APO and the NAO correlated very well on the interannual time scale, with the positive (negative) phase of the APO corresponding to the strong (weak) NAO. Such a relationship is well supported by the atmospheric dynamic process. When the APO is in the positive phase (characterized by the positive T′ anomaly over Asia and the negative T′ anomaly over the North Pacific in the upper troposphere), the upper tropospheric geopotential height increases over Asia and decreases over the North Pacific. Accordingly, anticyclonic circulation and cyclonic circulation anomalies are introduced, respectively, over Asia and south of the North Pacific, and a zonal teleconnection wave train is excited from Asia to the North Atlantic. As a consequence, an anomalous anticyclonic circulation prevails in the low level of the North Atlantic and an anomalous cyclonic circulation appears to its north, which corresponds to the atmospheric pattern of strong NAO. Further study proposes that the quasi‐stationary wave pattern emanating from the western North Pacific region may serve as a bridge for this linkage.
Light‐absorbing properties of ambient black carbon and brown carbon from fossil fuel and biomass burning sources
Authors: Healy R. M. , Wang J. M. , Jeong C.‐H. , Lee A. K. Y. , Willis M. D. , Jaroudi E. , Zimmerman N. , Hilker N. , Murphy M. , Eckhardt S. , Stohl A. , Abbatt J. P. D. , Wenger J. C. , Evans G. J. 
Published: June 2015

AbstractThe optical properties of ambient black carbon‐containing particles and the composition of their associated coatings were investigated at a downtown site in Toronto, Canada, for 2 weeks in June 2013. The objective was to assess the relationship between black carbon (BC) coating composition/thickness and absorption. The site was influenced by emissions from local vehicular traffic, wildfires in Quebec, and transboundary fossil fuel combustion emissions in the United States. Mass concentrations of BC and associated nonrefractory coatings were measured using a soot particle–aerosol mass spectrometer (SP‐AMS), while aerosol absorption and scattering were measured using a photoacoustic soot spectrometer (PASS). Absorption enhancement was investigated both by comparing ambient and thermally denuded PASS absorption data and by relating absorption data to BC mass concentrations measured using the SP‐AMS. Minimal absorption enhancement attributable to lensing at 781 nm was observed for BC using both approaches. However, brown carbon was detected when the site was influenced by wildfire emissions originating in Quebec. BC coating to core mass ratios were highest during this period (~7), and while direct absorption by brown carbon resulted in an absorption enhancement at 405 nm (>2.0), no enhancement attributable to lensing at 781 nm was observed. The efficiency of BC coating removal in the denuder decreased substantially when wildfire‐related organics were present and may represent an obstacle for future similar studies. These findings indicate that BC absorption enhancement due to lensing is minimal for downtown Toronto, and potentially other urban locations, even when impacted by long‐range transport events.
Relationships between climate variability, soil moisture, and Australian heatwaves
Authors: Perkins Sarah E. , Argüeso Daniel , White Christopher J. 
Published: June 2015

AbstractWhile it is established that low‐frequency climate variability modes have a dominant role on Australia's climate, limited work to date has focused on relationships between climate variability and Australian heatwaves. Moreover, heatwaves are a distinctive type of extreme weather that can be classified by multiple characteristics, such as intensity, frequency, duration, and timing. This study identifies the relationships between known modes of climate variability that influence Australian climate, and discrete seasonal characteristics of the intensity, frequency, duration, and timing of heatwaves. The large‐scale seasonal modes of the El Niño/Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD), and the Southern Annular Mode (SAM) are investigated for extended Austral summers commencing between the years 1911 and 2012. While ENSO is found to have the strongest relationship with Australian heatwave characteristics, this study finds that ENSO's influence differs between heatwave frequency, duration, intensity, and timing. Regions dominated by ENSO experience more, longer lasting and hotter heatwaves combined with an earlier commencement of the heatwave season during El Niño phases. The exception to this is southeast Australia, where SAM is generally more dominant. In contrast, the IOD provides little indication of seasonal heatwave characteristics due to its relative inactivity during the Austral summer months. Lastly, we show that antecedent soil moisture has varying strengths of relationships with Australian heatwave characteristics, exhibiting relationships with heatwave intensity and timing over some regions where none are detected between large‐scale modes. However, while significant relationships between dry antecedent soil moisture and extreme heatwaves do exist over Australia, these appear to be slightly weaker than similar relationships over Europe reported in other studies.
Heterogeneity in Karakoram glacier surges
Authors: Quincey Duncan J. , Glasser Neil F. , Cook Simon J. , Luckman Adrian 
Published: June 2015

AbstractMany Karakoram glaciers periodically undergo surges during which large volumes of ice and debris are rapidly transported downglacier, usually at a rate of 1–2 orders of magnitude greater than during quiescence. Here we identify eight recent surges in the region and map their surface velocities using cross‐correlation feature tracking on optical satellite imagery. In total, we present 44 surface velocity data sets, which show that Karakoram surges are generally short‐lived, lasting between 3 and 5 years in most cases, and have rapid buildup and relaxation phases, often lasting less than a year. Peak velocities of up to 2 km a−1 are reached during summer months, and the surges tend to diminish during winter months. Otherwise, they do not follow a clearly identifiable pattern. In two of the surges, the peak velocity travels down‐ice through time as a wave, which we interpret as a surge front. Three other surges are characterized by high velocities that occur simultaneously across the entire glacier surface, and acceleration and deceleration are close to monotonic. There is also no consistent seasonal control on surge initiation or termination. We suggest that the differing styles of surge can be partly accounted for by individual glacier configurations and that while some characteristics of Karakoram surges are akin to thermally controlled surges elsewhere (e.g., Svalbard), the dominant surge mechanism remains unclear. We thus propose that these surges represent a spectrum of flow instabilities and the processes controlling their evolution may vary on a glacier by glacier basis.
Developmental trajectories of aggressive behavior in children from ages 8 to 10: The role of sex and hormones
Authors: Azurmendi Aitziber , Pascual‐Sagastizabal Eider , Vergara Ana I. , Muñoz Jose M. , Braza Paloma , Carreras Rosario , Braza Francisco , Sánchez‐Martín José R. 
Published: June 2015

ObjectivesThis study explored the developmental trajectory of aggressive behavior from age 8 to age 10 in school‐aged children, taking into account possible sex differences, as well as the involvement of certain hormones.MethodsParticipants were 90 children (49 boys and 41 girls) from four schools. At the beginning of the study, the children were 8‐year old and were in 3rd grade of primary school. The second data collection phase was carried out two years later (at age 10) when the children were in 5th grade (primary). Their aggressive behavior was measured by the Direct and Indirect Aggression Scale, an instrument which uses peer rating. Hormone levels, testosterone, cortisol and estradiol were analyzed using an enzymoimmunoassay technique in saliva samples.ResultsThe results revealed a difference in aggressive behavior between the ages of 8 and 10, in boys only, who were found to be more aggressive at age 10. A regression analysis revealed that cortisol and estradiol contributed to explaining the changes observed in aggressive behavior in boys. Boys whose cortisol levels rose most between the ages of 8 and 10 were also those whose aggressive behavior increased most during the same timeframe. Moreover, boys whose estradiol levels rose most between the ages of 8 and 10 were also those whose aggressive behavior decreased most during the same timeframe.ConclusionsOur results highlight the importance of studying aggressive behavior from a longitudinal perspective, taking into account sex differences and biological measures. Am. J. Hum. Biol. 28:90–97, 2016. © 2015 Wiley Periodicals, Inc.
Prevalence of occupational exposure to carcinogens among workers of Arabic, Chinese and Vietnamese ancestry in Australia
Authors: Boyle Terry , Carey Renee N. , Glass Deborah C. , Peters Susan , Fritschi Lin , Reid Alison 
Published: June 2015

BackgroundAlthough job‐related diseases result in more deaths per year than job‐related injuries, most research concerning ethnic minority workers has concerned accidents and injuries rather than disease‐causing exposures such as carcinogens.MethodsWe conducted a telephone‐based cross‐sectional survey to estimate the prevalence of occupational exposure to carcinogens among a sample of ethnic minority workers in Australia, and compared their exposure prevalence to that of a sample of the general Australian‐born working population (‘Australian workers’).ResultsOne‐third of the ethnic minority workers were exposed to at least one carcinogen at work. The likelihood of exposure to carcinogens was not significantly different from that of Australian workers, although the likelihood of exposure to individual carcinogens varied by ethnicity.ConclusionKnowing the prevalence of exposure to carcinogens in the workplace in different ethnic groups will allow better targeted and informed occupational health and safety measures to be implemented where necessary. Am. J. Ind. Med. 58:923–932, 2015. © 2015 Wiley Periodicals, Inc.
Efficient Palladium‐Catalyzed Direct C−H Phenylselenylation of (Hetero)Arenes in Water
Authors: Jin Weiwei , Zheng Poonnapa , Wong Wing‐Tak , Law Ga‐Lai 
Published: June 2015

AbstractAn efficient, palladium‐catalyzed, direct phenylselenylation of arenes and heteroarenes in water by using N‐(phenylseleno)phthalimide (N‐PSP) as the coupling partner is reported. A variety of diaryl selenides with high functional group tolerance have been obtained in good to excellent yields and regioselectivity.
Precise Macroscopic Supramolecular Assembly by Combining Spontaneous Locomotion Driven by the Marangoni Effect and Molecular Recognition
Authors: Xiao Meng , Xian Yiming , Shi Feng 
Published: June 2015

AbstractMacroscopic supramolecular assembly bridges fundamental research on molecular recognition and the potential applications as bulk supramolecular materials. However, challenges remain to realize stable precise assembly, which is significant for further functions. To handle this issue, the Marangoni effect is applied to achieve spontaneous locomotion of macroscopic building blocks to reach interactive distance, thus contributing to formation of ordered structures. By increasing the density of the building blocks, the driving force for assembly transforms from a hydrophobic–hydrophobic interaction to hydrophilic–hydrophilic interaction, which is favorable for introducing hydrophilic coatings with supramolecular interactive groups on matched surfaces, consequently realizing the fabrication of stable precise macroscopic supramolecular assemblies.