bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small‐scale sea ice deformation during N‐ICE2015: From compact pack ice to marginal ice zone
Authors: Oikkonen Annu , Haapala Jari , Lensu Mikko , Karvonen Juha , Itkin Polona 
Published: May 2017

AbstractWe studied small‐scale (50 m to 5 km) sea ice deformation from ship radar images recorded during the N‐ICE2015 campaign. The campaign consisted of four consecutive drifting ice stations (Floes 1–4) north of Svalbard, with a total duration of nearly 5 months. Deformation was calculated using 5 different time intervals from 10 min to 24 h, and the deformation rate was found to depend strongly on the time scale. Floes 1–3 had a mean deformation rate within the range of 0.06–0.07 h−1 with the interval of 10 min, and 0.03–0.04 h−1 with the interval of 1 h. Floe 4 represented marginal ice zone (MIZ) with very high deformation rate, 0.14/0.08 h−1 with the interval of 10 min/1 h. Deep in the ice pack, high deformation rates occurred only with high wind and drift speed, while in MIZ they were found also during calm conditions. The deformation rates were found to follow power law scaling with respect to length and time scale even on this small scale and in small domain (15 km × 15 km). The length scale dependence of deformation rate depends on the time scale: the power law scaling exponent β of the whole study period decreases from 0.82 to 0.52 with the time interval increasing from 10 min to 24 h. Ship radar images reveal the importance of the deformation history of the ice pack, since the deformation events were initialized along the lines of previous damages.
A computational study on the nature of meso‐β scale vortex coalescence in a tropical atmosphere
Authors: Schecter David A. 
Published: May 2017

AbstractTropical weather systems commonly contain a variety of mesoscale vortices whose interactions may influence the timing of tropical cyclone formation. Previous computational studies have found that interactions ending in coalescence can either help or hinder development depending on the specific circumstances. Despite the potential importance of mesoscale vortex merger, complications introduced by baroclinic effects and diabatic processes have impeded progress toward elucidating its mechanics. The present study is an effort to advance current understanding by way of idealized numerical experiments with a cloud‐permitting model. Direct comparisons are made between dry adiabatic and moist diabatic simulations of meso‐β (20–200 km) scale vortex merger on a tropical oceanic f‐plane. Consistent with a number of earlier studies, deep cumulus convection is found to accelerate the late stage of surface‐concentrated vortex merger over a warm ocean. On the other hand, incorporating artificial radiation and cloud processes into the numerical model substantially hinders the merger of middle‐tropospheric vortices over a moderately cooler ocean. Such hindering coincides with the partial suppression of shear‐induced vortex misalignments whose amplifications and rotations appear to be essential to the dry adiabatic merger mechanism. The aforementioned dry merger mechanism is examined in detail. Irrotational winds linked to the horizontal divergence field are found to largely control the system‐centric influx of absolute vorticity, in sharp contrast to ideal two‐dimensional hydrodynamics. The consequences of lowering (raising) the sea‐surface temperature under the moist surface‐concentrated (middle‐tropospheric) system are briefly addressed.
Martian mesospheric cloud observations by IUVS on MAVEN: Thermal tides coupled to the upper atmosphere
Authors: Stevens M. H. , Siskind D. E. , Evans J. S. , Jain S. K. , Schneider N. M. , Deighan J. , Stewart A. I. F. , Crismani M. , Stiepen A. , Chaffin M. S. , McClintock W. E. , Holsclaw G. M. , Lefèvre F. , Lo D. Y. , Clarke J. T. , Montmessin F. , Jakosky B. M. 
Published: May 2017

AbstractWe report observations of Martian mesospheric ice clouds and thermospheric scale heights by the Imaging Ultraviolet Spectrograph on NASA's Mars Atmosphere and Volatile Evolution mission. The clouds are observed between 6 A.M. and 8 A.M. local time using mid‐UV limb observations between 60 and 80 km tangent altitude where ice particles that scatter sunlight can appear as detached layers near the equator. The equatorial longitudinal distribution shows populations of clouds near −110°E and −10°E as well as a population near 90°E, which does not have a clear precedent. The cloud populations indicate a wave 3 pattern near 70 km, which is confirmed by independent mesospheric temperature observations. Scale heights 100 km above the clouds derived from concurrent Imaging Ultraviolet Spectrograph (IUVS) observations also reveal a wave 3 longitudinal structure, suggesting that the temperature oscillations enabling the formation of mesospheric clouds couple to the upper atmosphere.
The shallow magma chamber of Stromboli Volcano (Italy)
Authors: Patanè D. , Barberi G. , De Gori P. , Cocina O. , Zuccarello L. , Garcia‐Yeguas A. , Castellano M. , D'Alessandro A. , Sgroi T. 
Published: May 2017

AbstractIn this work, we integrate artificial and natural seismic sources data to obtain high‐resolution images of the shallow inner structure of Stromboli Volcano. Overall, we used a total of 21,953 P readings from an active seismic experiment and an additional 2731 P and 992 S readings deriving from 269 local events. The well‐defined Vp, Vs, and Vp/Vs tomograms have highlighted the following: (i) the region where magma cumulates at shallow depths (2–4 km below sea level (bsl)), forming an elongated NE‐SW high‐velocity body (Vp ≥ 6.0 km/s and Vs ≥ 3.5 km/s), with a very fast velocity core (6.5 ≤ Vp < 7.0 km/s) of ~2 km3; (ii) the presence of some near‐vertical pipe‐like structures, characterized by relatively high P velocities values, mainly linked to past activity (e.g., Strombolicchio); and (iii) a near‐vertical pipe‐like volume with high Vp/Vs (1.78 ÷ 1.85), located beneath to the craters (down to ~1.0 km bsl), overlying a deeper region (1.0 to 3.0 km bsl) with low Vp/Vs (1.64 ÷ 1.69), interpreted as the actual and preferential pathway of magma toward the surface. Our results demonstrate the importance of combining passive and active seismic data to improve, in a tomographic inversion, the resolution of the volcanic structures and to discover where magma may be stored.
Initiation of positive streamer corona in low thundercloud fields
Authors: Cai Qiheng , Jánský Jaroslav , Pasko Victor P. 
Published: May 2017

AbstractFormation of filamentary gas discharge forms, commonly referred to as streamers, is one of the conditions required for initiation and subsequent propagation of lightning leaders. It is quantitatively demonstrated that streamers can be initiated under thunderstorm conditions when two precipitation particles cause an enhancement of the electric field by passing in close vicinity of each other. Conditions for avalanche‐to‐streamer transition are documented using a model of two spherical hydrometeor particles placed in uniform ambient field. The results are presented in scaled form using similarity relations for gas discharges and can be applied for a wide range of thunderstorm conditions, including different air pressures, electric fields, and particle dimensions.
Anomalously large complete stress drop during the 2016 Mw 5.2 Borrego Springs earthquake inferred by waveform modeling and near‐source aftershock deficit
Authors: Ross Z. E. , Kanamori H. , Hauksson E. 
Published: May 2017

AbstractThe 2016 Mw 5.2 Borrego Springs earthquake occurred in the trifurcation area of the San Jacinto Fault Zone and generated more than 23,000 aftershocks. We analyze source properties of this earthquake along with 12,487 precisely located aftershock hypocenters to obtain an unusually detailed view of the rupture process and energy budget for this moderate earthquake. Source time functions are obtained using an empirical Green's function approach and are inverted for a slip distribution on the fault plane. The rupture propagated unilaterally to the northwest over a distance of 1.8 km, resulting in clear directivity signals. Two asperities are identified and the maximum slip is 2.54 m, resulting in a static stress drop of 78.2 MPa. Over 97% of the aftershocks occur more than 1 rupture length from the slip area. We conclude that the Borrego Springs earthquake had a complete stress drop and estimate the seismic efficiency to be 15–26%.
Parallel electron heating in the magnetospheric inflow region
Authors: Wang Shan , Chen Li‐Jen , Hesse Michael , Wilson Lynn B. , Bessho Naoki , Gershman Daniel J. , Ergun Robert E. , Phan Tai D. , Burch James L. , Dorelli John C. , Giles Barbara , Torbert Roy B. , Pollock Craig J. , Russell Christopher T. , Strangeway Robert , Avanov Levon , Lavraud Benoit , Moore Thomas E. 
Published: May 2017

AbstractWe analyzed 20 reconnection events observed by the Magnetosphere MultiScale mission, finding that in a subregion of the magnetospheric inflow, the electron temperature parallel to the magnetic field (Te||) decreases toward the separatrix with increasing densities. Such Te|| variation is not consistent with the heating through the parallel potential mechanism for magnetospheric electrons. Associated with the change in Te||, low‐energy gyrotropic magnetosheath‐like electrons are observed. These electrons may come from the magnetosheath, penetrate to the magnetospheric side possibly due to waves in the lower hybrid frequency range, and do not experience as much energization as those from deeper in the magnetosphere. In addition, as Te|| decreases, the high‐energy field‐aligned phase‐space densities decrease or fluctuate significantly over time. Wave‐particle interaction might produce energy conversion and cause the high‐energy phase‐space density variations.
Antenna structures and cloud‐to‐ground lightning location: 1995–2015
Authors: Kingfield Darrel M. , Calhoun Kristin M. , de Beurs Kirsten M. 
Published: May 2017

AbstractSpatial analyses of cloud‐to‐ground (CG) lightning occurrence due to a rapid expansion in the number of antenna towers across the United States are explored by gridding 20 years of National Lightning Detection Network data at 500 m spatial resolution. The 99.8% of grid cells with ≥100 CGs were within 1 km of an antenna tower registered with the Federal Communications Commission. Tower height is positively correlated with CG occurrence; towers taller than 400 m above ground level experience a median increase of 150% in CG lightning density compared to a region 2 km to 5 km away. In the northern Great Plains, the cumulative CG lightning density near the tower was around 138% (117%) higher than a region 2 to 5 km away in the September–February (March–August) months. Higher CG frequencies typically also occur in the first full year following new tower construction, creating new lightning hot spots.
Systematic fluctuations in the global seismic moment release
Authors: Zaliapin Ilya , Kreemer Corné 
Published: May 2017

AbstractWe revisit the significance of the increased number of great earthquakes since December 2004. An analysis of the global seismic moment release during 1918–2014 inferred from the International Seismological Centre catalog rejects a null hypothesis of independence between earthquake seismic moments and occurrence times. Our results suggest the existence of temporal variation in the seismic moment distribution on a global scale with decreased moment release during 1975–2004 and a transition to a regime with increased moment release during the 1960s and after December 2004. We use complementary likelihood and regression analyses based on nonparametric resampling and parametric Monte Carlo simulations to construct tests powerful enough to reject the null hypothesis of independence.
Estimation of the differential stress from the stress rotation angle in low permeable rock
Authors: Ziegler Moritz O. , Heidbach Oliver , Zang Arno , Martínez‐Garzón Patricia , Bohnhoff Marco 
Published: May 2017

AbstractRotations of the principal stress axes are observed as a result of fluid injection into reservoirs. We use a generic, fully coupled 3‐D thermo‐hydro‐mechanical model to investigate systematically the dependence of this stress rotation on different reservoir properties and injection scenarios. We find that permeability, injection rate, and initial differential stress are the key factors, while other reservoir properties only play a negligible role. In particular, we find that thermal effects do not significantly contribute to stress rotations. For reservoir types with usual differential stress and reservoir treatment the occurrence of significant stress rotations is limited to reservoirs with a permeability of less than approximately 10−12 m2. Higher permeability effectively prevents stress rotations to occur. Thus, according to these general findings, the observed principal stress axes rotation can be used as a proxy of the initial differential stress provided that rock permeability and fluid injection rate are known a priori.
Spectral properties and associated plasma energization by magnetosonic waves in the Earth's magnetosphere: Particle‐in‐cell simulations
Authors: Sun Jicheng , Gao Xinliang , Lu Quanming , Chen Lunjin , Liu Xu , Wang Xueyi , Tao Xin , Wang Shui 
Published: May 2017

AbstractIn this paper, we perform a 1‐D particle‐in‐cell (PIC) simulation model consisting of three species, cold electrons, cold ions, and energetic ion ring, to investigate spectral structures of magnetosonic waves excited by ring distribution protons in the Earth's magnetosphere, and dynamics of charged particles during the excitation of magnetosonic waves. As the wave normal angle decreases, the spectral range of excited magnetosonic waves becomes broader with upper frequency limit extending beyond the lower hybrid resonant frequency, and the discrete spectra tends to merge into a continuous one. This dependence on wave normal angle is consistent with the linear theory. The effects of magnetosonic waves on the background cold plasma populations also vary with wave normal angle. For exactly perpendicular magnetosonic waves (parallel wave number k|| = 0), there is no energization in the parallel direction for both background cold protons and electrons due to the negligible fluctuating electric field component in the parallel direction. In contrast, the perpendicular energization of background plasmas is rather significant, where cold protons follow unmagnetized motion while cold electrons follow drift motion due to wave electric fields. For magnetosonic waves with a finite k||, there exists a nonnegligible parallel fluctuating electric field, leading to a significant and rapid energization in the parallel direction for cold electrons. These cold electrons can also be efficiently energized in the perpendicular direction due to the interaction with the magnetosonic wave fields in the perpendicular direction. However, cold protons can be only heated in the perpendicular direction, which is likely caused by the higher‐order resonances with magnetosonic waves. The potential impacts of magnetosonic waves on the energization of the background cold plasmas in the Earth's inner magnetosphere are also discussed in this paper.
Evaluation of anthropogenic influences on the Luhuitou fringing reef via spatial and temporal analyses (from isotopic values)
Authors: Cao D. , Cao W. , Yu K. , Wu G. , Yang J. , Su X. , Wang F. 
Published: May 2017

AbstractCoral reefs have suffered remarkable declines worldwide. Nutrient overenrichment is considered to be one of the primary local causes. The Luhuitou fringing reef in southern China is a well‐known tourist destination that is subject to enormous coastal renovation. The mean δ13C, δ15N value, and carbon over nitrogen ratio (C/N) of particulate organic matter were −21.56 ± 1.94‰, 7.04 ± 3.81‰, and 5.81 ± 1.86, respectively, suggesting mixed sources of carbon and nitrogen. The IsoError calculations suggested that marine phytoplankton and marine benthic algae dominated the majority of carbon sources, while anthropogenic and terrestrial organic nitrogen dominated the nitrogen sources. A tendency toward greater terrestrial detritus and anthropogenic‐derived discharges was found during dry seasons and greater marine‐derived organic matter during wet seasons. These results demonstrated the existence of anthropogenic influences and high dissolved inorganic nitrogen concentrations and C/N ratios. Anthropogenic nutrient discharge moderated nitrogen limitation, whereas phosphorus became more important to the reef ecosystem. Despite the marine carbon sources dominated, freshwater and terrestrial‐derived organic carbon sources were also very important. Meanwhile, anthropogenic and terrestrial organic nitrogen sources were dominant. Therefore, pollution from more extensive region and anthropogenic activities from riverine sewage discharges adjacent to reefs should be focused to effectively reduce human‐derived nutrients on reefs.
Immunodeficiency: Secondary
Authors: Bright Philip , Richter Alex 
Published: May 2017

Abstract

Secondary immunodeficiency (SID) refers to an acquired immunodeficiency secondary to an extrinsic cause (e.g. disease, treatment) and can occur when any condition or treatment causes a reduction in number or function of immune components. Opportunistic or particularly severe infections should raise the suspicion of SID. SID is relatively common, and worldwide the most prevalent causes include malnutrition and advancing age. The aetiologies of SID can be loosely grouped into those caused by the related abnormalities of general health, underlying disease, barrier integrity or iatrogenic influences. Issues with general health that result in SID include malnutrition, advancing age, smoking and alcohol. Underlying diseases that cause SID include haematological malignancies, splenectomy/hyposplenism and some infections (e.g. human immunodeficiency virus (HIV)). Many diverse injuries, treatments or diseases can reduce barrier integrity resulting in SID, as well as a wide range of iatrogenic interventions. The treatment of SID depends on both the presentation and aetiology.

Key Concepts

Secondary immunodeficiency refers to an acquired immunodeficiency secondary to an extrinsic cause.

The aetiology of secondary immunodeficiency is often multifactorial and may present with diverse opportunistic infections.

Secondary immunodeficiency is common, and the most common aetiology worldwide is malnutrition.

Causes of secondary immunodeficiency can be loosely defined by aetiology into disorders of general health, barrier integrity, relating to underlying diseases or as iatrogenic.

Severe presentations of common infections and certain characteristic opportunistic infections should raise the suspicion of secondary immunodeficiency.

Many secondary immunodeficiencies relate to the use of medications, particularly the new generation of biological agents.

Infections, as well as being a result of immunodeficiency, may also cause secondary immunodeficiency.

The treatment of secondary immunodeficiency is complicated and dependent on both the presentation and the aetiology of the immunodeficiency.
Insurance and Genetic Information
Authors: Bombard Yvonne , King Wong Eugene , Lemmens Trudo 
Published: May 2017

AbstractAdvances in genomic technology have expanded the number of tests for which individuals can obtain additional risk estimates about their susceptibilities to disease. Genomic information that predicts disease risk is relevant to insurers because the amount that policyholders pay for insurance coverage is determined by assessing their level of disease risk. Without access to genomic information, insurers are concerned that individuals may purchase more insurance at unadjusted premiums, leading to adverse selection. However, not all genomic information is useful from an insurance viewpoint, and the complexity of interpreting genetic variants, coupled with the possibility of incidental findings, raises ethical issues with using applicants' genomic testing results. Moreover, some people are reluctant to undergo genetic testing or participate in genomic research because of the fear that they may have difficulty in obtaining insurance after disclosing their genomic results to insurers. As genomic testing becomes more prevalent, there are concerns that sections of the population will be denied insurance because of their genetic profile. The question of what governments should do about this is one that has been debated in many countries.Key ConceptsInsurers request genetic test results from applicants to enable them to make an accurate assessment of their health risks in the underwriting process. However, patients and the public fear that they may have difficulty in obtaining insurance after disclosing their genomic results to insurers.Not all genetic tests are useful for insurance underwriting; this will depend on the clinical validity and utility of the test, the nature and penetrance of the disease and the availability of treatment or management strategies.Use of genomic data for insurance underwriting also raises ethical concerns due to the complexity of interpreting genomic variants and the possibility of discovering incidental findings from genomic data.The public's fear of genetic discrimination by insurers appears to have consequences for public health and genetic research programme initiatives.Moratoria or legislation to prohibit the use of genetic test results by insurers has been adopted by many countries to prevent insurance discrimination.However, other ways to regulate the use of genetic tests in insurance include human rights or privacy‐based approaches.
Molecular Genetics of Penile Cancer
Authors: McCormick Barrett , Baumgarten Adam , Spiess Philippe E 
Published: May 2017

Abstract

Penile cancer is a rare malignancy in the United States and Europe but has a much higher prevalence in certain geographical areas including South America and Africa. Compared with other urological malignancies, there remains a paucity of information regarding the molecular mechanisms involved in penile cancer carcinogenesis. It is generally understood that there are two separate molecular pathways that contribute to carcinogenesis, one of which is largely related to human papillomavirus (HPV) infection. The second mechanism is much less clearly understood and is related to a combination of factors including those influenced by environmental effects and somatic or epigenetic changes. However, there also remains an element of interplay between the two mechanisms that adds to the complexity of understanding the disease. The aim of this review is to outline the current understanding of the genetic factors, current research and future directions involved in understanding the disease.

Key Concepts

Penile cancer is a rare entity and the mechanisms behind its carcinogenesis are not completely understood.

It is generally understood that the pathogenesis of penile cancer may related to both HPV mediated and non-mediated mechanisms.

The ability of the human papillomavirus to lead to malignancy is dependent on breakdown of normal cell degradation mechanisms as well as cell cycle alterations leading to uninhibited cell proliferation.

Non‐HPV mediated pathogenesis has numerous potential mechanisms and remains an ongoing area of study.

Continued focus on centers of excellence as well as international collaborations will be needed to continue to develop a full understanding of the disease.