bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying How Density Gradients and Front Curvature Affect Carbon Detonation Strength during SNe Ia
Authors: Miles Broxton J. , Townsley Dean M. , Shen Ken J. , Timmes F. X. , Moore Kevin
Published: January 2019

Accurately reproducing the physics behind the detonations of SNe Ia and the resultant nucleosynthetic yields is important for interpreting observations of spectra and remnants. The scales of the processes involved span orders of magnitudes, making the problem computationally impossible to ever fully resolve in full-star simulations in the present and near future. In the lower density regions of the star, the curvature of the detonation front will slow the detonation, affecting the production of intermediate mass elements. We find that shock strengthening due to the density gradient present in the outer layers of the progenitor is essential for understanding the nucleosynthesis there, with burning extending well below the density at which a steady-state detonation is extinct. We show that a complete reaction network is not sufficient to obtain physical detonations at high densities and modest resolution due to numerical mixing at the unresolved reaction front. At low densities, below 6 × 105 g cm−3, it is possible to achieve high enough resolution to separate the shock and the reaction region, and the abundance structure predicted by fully resolved quasi-steady-state calculations is obtained. For our best current benchmark yields, we utilize a method in which the unresolved portion of Lagrangian histories are reconstructed based on fully resolved quasi-steady-state detonation calculations. These computations demonstrate that under-resolved simulations agree approximately, ∼10% in post-shock values of temperature, pressure, density, and abundances, with expected detonation structures sufficiently far from the under-resolved region, but that there is still room for some improvement in the treatment of subgrid reactions in the hydrodynamics to before better than 1% can be achieved at all densities.
AstroSat SXT Observations of Her X-1
Authors: Leahy D. A. , Chen Y.
Published: January 2019

Two observations of the X-ray binary system Her X-1 by the AstroSat Soft X-ray Telescope were carried out in 2017. The first was during Low State and Turn-On, the second was during Main High State without and with dips. During Main High without dips, the power-law continuum, 1 keV emission line complex, and soft blackbody-like emission from Her X-1 are detected. Evidence is found in the spectrum for a highly ionized absorber, consistent with the recently detected corona in Her X-1. The X-ray spectra from different states are compared. The 6.4 keV fluorescent iron line is clearly detected in Low State. The different spectrum components are highly variable between states.
Mapping the Conditions for Hydrodynamic Instability on Steady-State Accretion Models of Protoplanetary Disks
Authors: Pfeil Thomas , Klahr Hubert
Published: January 2019

Hydrodynamic instabilities in disks around young stars depend on the thermodynamic stratification of the disk and on the local rate of thermal relaxation. Here, we map the spatial extent of unstable regions for the Vertical Shear Instability (VSI), the Convective Overstability (COS), and the amplification of vortices via the Subcritical Baroclinic Instability (SBI). We use steady-state accretion disk models, including stellar irradiation, accretion heating, and radiative transfer. We determine the local radial and vertical stratification and thermal relaxation rate in the disk, which depends on the stellar mass, disk mass, and mass accretion rate. We find that passive regions of disks—that is, the midplane temperature dominated by irradiation—are COS unstable about one pressure scale height above the midplane and VSI unstable at radii >10 au. Vortex amplification via SBI should operate in most parts of active and passive disks. For active parts of disks (midplane temperature determined by accretion power), COS can become active down to the midplane. The same is true for the VSI because of the vertically adiabatic stratification of an internally heated disk. If hydrodynamic instabilities or other nonideal MHD processes are able to create α-stresses (>10−5) and released accretion energy leads to internal heating of the disk, hydrodynamic instabilities are likely to operate in significant parts of the planet-forming zones in disks around young stars, driving gas accretion and flow structure formation. Thus, hydrodynamic instabilities are viable candidates to explain the rings and vortices observed with the Atacama Large Millimeter/submillimeter Array and Very Large Telescope.
Identifying Variability in Deeply Embedded Protostars with ALMA and CARMA
Authors: Francis Logan , Johnstone Doug , Dunham Michael M. , Hunter Todd R. , Mairs Steve
Published: January 2019

Variability of pre-main-sequence stars observed at optical wavelengths has been attributed to fluctuations in the mass accretion rate from the circumstellar disk onto the forming star. Detailed models of accretion disks suggest that young deeply embedded protostars should also exhibit variations in their accretion rates, and that these changes can be tracked indirectly by monitoring the response of the dust envelope at mid-IR to millimeter wavelengths. Interferometers such as the Atacama Large Millimeter/submillimeter Array (ALMA) offer the resolution and sensitivity to observe small fluctuations in brightness at the scale of the disk where episodic accretion may be driven. In this work, we present novel methods for comparing interferometric observations and apply them to Combined Array for Research in Millimeter-wave Astronomy (CARMA) and ALMA 1.3 mm observations of deeply embedded protostars in Serpens taken 9 yr apart. We find no brightness variation above the limits of our analysis of a factor of ≳50%, due to the limited sensitivity of the CARMA observations and small number of sources common to both epochs. We further show that follow-up ALMA observations with a similar sample size and sensitivity may be able to uncover variability at the level of a few percent, and discuss implications for future work.
Octahedron-based Projections as Intermediate Representations for Computer Imaging: TOAST, TEA, and More
Authors: McGlynn Thomas , Fay Jonathan , Wong Curtis , Rosenfield Philip
Published: January 2019

This paper defines and discusses a set of rectangular all-sky projections that have no singular points, notably the Tesselated Octahedral Adaptive Spherical Transformation (or TOAST) developed initially for the WorldWide Telescope. These have proven to be useful as intermediate representations for imaging data where the application transforms dynamically from a standardized internal format to a specific format (projection, scaling, orientation, etc.) requested by the user. TOAST is strongly related to the Hierarchical Triangular Mesh pixelization and is particularly well adapted to situations where one wishes to traverse a hierarchy of images increasing in resolution. Because it can be recursively computed using a very simple algorithm it is particularly adaptable to use with graphical processing units.
Efficacy of Adding Oral Simvastatin to Topical Therapy for Treatment of Psoriasis: The Vietnamese Experience
Authors: Trong Hao Nguyen , Nguyen Tat Thang , Nguyen Anh Tu Tran , Uyen Nhi Pham , Nguyen Van Thuong , Tran Hau Khang , Gandolfi Marco , Satolli Francesca , Feliciani Claudio , Tirant Michael , Vojvodic Aleksandra , Lotti Torello
Published: January 2019

BACKGROUND: Psoriasis, the prevalence of which ranges from 2% to 3% of the general population, has been recently recognised as not only a chronic inflammatory skin disorder but also an immunometabolic systemic disease. Dyslipidemia is one of the most important comorbidities of psoriasis. Statins, frequently used as anti-hyperlipidemic agents, may be beneficial in the treatment of several autoimmune diseases, including psoriasis, due to their anti-inflammatory and immunomodulatory characteristics. Hence, we hypothesised that using this medication was not only beneficial for reducing hyperlipidemia but also improving psoriatic conditions.
AIM: We conducted a study to determine the prevalence of dyslipidemia in psoriatic patients as well as whether the addition of statins (simvastatin prescribed forms) to standard topical antipsoriatic treatment can improve skin lesions in psoriatic patients.
METHODS: A group of 128 psoriatic patients and 128 healthy controls who were matched with the patients regarding ethnicity, age, and sex were enrolled, and their lipid concentrations were determined. Furthermore, sixty patients were randomly selected from the former group and divided into two treatment subgroups to evaluate the effect of statins on the severity of psoriasis using the PASI score.
RESULTS: We found that the rate of dyslipidemia in the patient group was significantly higher than in the healthy group (53.9% versus 21.9%, p < 0.001), particularly the triglyceride concentration (1.86 ± 1.17 versus 1.43 ± 0.79 mg/dL, p < 0.001). Also, the PASI score reduction in the simvastatin-treated subgroup was significantly different from that in the placebo-treated one after eight weeks of therapy (8.63 ± 4.78 versus 5.34 ± 3.59, p < 0.01).
CONCLUSION: This study showed that simvastatin might play a role in controlling hyperlipidemia and in turn decrease the PASI score in psoriatic patients.
The Relationship between HLA-B27, HLA-Cw06, HLA-DR7 and Psoriatic Arthritis in Vietnamese Patients: Disease Progression and Therapeutic Burden
Authors: Ngo Minh Vinh , Bui Thi Van , Chau Van Tro , Nguyen Ngoc Trai , Ngoc Anh Tran , Dang Van Em , Gandolfi Marco , Satolli Francesca , Feliciani Claudio , Tirant Michael , Vojvodic Aleksandra , Lotti Torello
Published: January 2019

We conducted a prospective, cross-sectional study at Ho Chi Minh City Hospital of Dermato Venereology from January 2016 to March 2017 in 40 psoriatic arthritis (PsA) patients to evaluate the disease progression and therapeutic burden about the HLA patterns. Based upon our results, PsA with HLA-B27 (+) had a threat of severe arthritis. PsA with HLA-Cw06 (+) had a higher risk of earlier onset and shorter duration for plaque psoriasis to transform into PsA. HLA-DR7 (+) in PsA delayed the time for conversion from plaque psoriasis into PsA. These findings are quite similar to other studies in the literature.
The Efficacy of a Two-Fold Increase of H1-Antihistamine in the Treatment of Chronic Urticaria - the Vietnamese Experience
Authors: Tran Thi Huyen , Thi Lan Pham , Nguyen Van Thuong , Thi Minh Phuong Pham , Nguyen Trong Hao , Chau Van Tro , Nguyen Huu Sau , Trinh Minh Trang , Dinh Huu Nghi , Hoang Van Tam , Cam Van Tran , Le Huyen My , Tran Hau Khang , Thanh Thuy Nguyen , Thi Phuong Hoang , Thuy Linh Nguyen , Gandolfi Marco , Satolli Francesca , Feliciani Claudio , Tirant Michael , Vojvodic Aleksandra , Lotti Torello
Published: January 2019

BACKGROUND: Chronic urticaria, a mast cell-driven condition, is common, debilitating and hard to treat. H1-antihistamines are the first line treatment of chronic urticaria, but often patients do not get satisfactory relief with the recommended dose. European guidelines recommend increased antihistamine doses up to four-fold.
AIM: We conducted this study to evaluate the efficacy of increased H1-antihistamine doses up to two-fold in Vietnamese chronic urticaria patients.
METHODS: One hundred and two patients with chronic urticaria were recruited for treatment with levocetirizine (n = 52) or fexofenadine (n = 50). Treatment started at the conventional daily dose of 5 mg levocetirizine or 180 mg fexofenadine for 2 weeks and then increased to 10 mg levocetirizine or 360 mg fexofenadine for 2 weeks if patients did not have an improvement in symptoms. At week 0, week 2 and week 4 wheal, pruritus, size of the wheal, total symptom scores, and associated side-effects were assessed.
RESULTS: With the conventional dose, the total symptom scores after week 2 decreased significantly in both groups compared to baseline figures, i.e. 7.4 vs 2.3 for levocetirizine group and 8.0 vs 2.6 for fexofenadine group (p < 0.05). However, there were still 26 patients in each group who did not have improvements. Of these 26 patients, after having a two-fold increase of the conventional dose, 11.5% and 38.5% became symptom-free at week 4 in levocetirizine group and fexofenadine group, respectively. At week 4 in both groups, the total symptom scores had significantly decreased when compared with those at week 2 (2.8 Â± 1.5 versus 4.7 Â± 1.6 in levocetirizine group; 2.1 Â± 1.9 versus 5.1 Â± 1.4 in fexofenadine group). In both groups, there was no difference in the rate of negative side effects between the conventional dose and the double dose.
CONCLUSION: This study showed that increasing the dosages of levocetirizine and fexofenadine by two-fold improved chronic urticaria symptoms without increasing the rate of negative side effects.
Efficacy of BAFF in Monitoring Treatment Response in Early Vietnamese Systemic Sclerosis Patients
Authors: Nguyen Minh Vu , Tran Hau Khang , Takashi Matushita , Nguyen Ha Vinh , Hoang Bao Long , Le Huyen My , Le Huu Doanh , Nguyen Van Thuong , Gandolfi Marco , Satolli Francesca , Feliciani Claudio , Tirant Michael , Vojvodic Aleksandra , Lotti Torello
Published: January 2019

BACKGROUND: B-cell activating factor (BAFF) is considered to have a role in the pathogenesis of systemic sclerosis (SSc).
AIM: We conducted a longitudinal study on early SSc patients to determine the change in BAFF serum level after treatment and its association with organ involvements.
METHODS: A total of 46 patients (32 diffuse, 14 limited) were recruited, among which 35 patients (24 diffuse, 11 limited) completed 12-month follow-up.
RESULTS: Higher pretreatment BAFF levels were observed in patients with positive anti-topoisomerase antibody (ATA) (2252.1 Â± 899.7 pg/ml versus 1475.5 Â± 697.6 pg/ml in ATA-negative patients; p = 0.01) and muscular involvement (2741.9 Â± 1039.9 pg/ml versus 1897.2 Â± 762.9 pg/ml in patients without muscular involvement; p = 0.005). Lower levels were observed in patients with interstitial lung disease (ILD) (1926.7 Â± 757.9 pg/ml versus 2721.6 Â± 1131.4 pg/ml in non-ILD patients; p = 0.01). After treatment, BAFF level reduced significantly in diffuse SSc patients (1652.2 Â± 892.7 pg/ml versus 2147.6 Â± 945.5 pg/ml before treatment; p = 0.03).
CONCLUSION: Patients with worsening outcome had the highest pretreatment BAFF level and was associated with increased BAFF level after treatment. BAFF can be used to predict and monitor patientsâ€™ response to therapy.
Apophysomyces thailandensis (Mucorales, Mucoromycota), a new species isolated from soil in northern Thailand and its solubilization of non-soluble minerals
Authors: Khuna Surapong , Suwannarach Nakarin , Kumla Jaturong , Meerak Jomkhwan , Nuangmek Wipornpan , Kiatsiriroat Tanongkiat , Lumyong Saisamorn
Published: January 2019

A new species of soil fungi, described herein asApophysomycesthailandensis, was isolated from soil in Chiang Mai Province, Thailand. Morphologically, this species was distinguished from previously describedApophysomycesspecies by its narrower trapezoidal sporangiospores. A physiological determination showed thatA.thailandensisdiffers from otherApophysomycesspecies by its assimilation of D-turanose, D-tagatose, D-fucose, L-fucose, and nitrite. A phylogenetic analysis, performed using combined internal transcribed spacers (ITS), the large subunit (LSU) of ribosomal DNA (rDNA) regions, and a part of the histone 3 (H3) gene, lends support to our the finding thatA.thailandensisis distinct from otherApophysomycesspecies. The genetic distance analysis of the ITS sequence supportsA.thailandensisas a new fungal species. A full description, illustrations, phylogenetic tree, and taxonomic key to the new species are provided. Its metal minerals solubilization ability is reported.
Relationship between performance strategies, resilience qualities, riding experience and competitive performance of show jumping riders
Authors: Iungano H.M. , Lancaster B.E. , Wolframm I.
Published: January 2019

Equestrian sports are considered high in risk, and successful athletes must achieve resilience to recover from adversities inherent to their riding career. The objective of this study is to identify which factors present in show jumping riders are related to resilient abilities, and how they may be improved. 101 British competitive show jumping riders were asked to complete a questionnaire about their riding experience and to respond to two tests: (1) test of performance strategies (TOPS 3), which analyses the use of self-talk, emotional control, automaticity, goal setting, imagery, activation, relaxation, negative thinking and attention control; and (2) Connor-Davidson resilience scale (CD-RISC-10), which evaluates resilient abilities. Where available, competition results were also analysed. Resilience scores had positive correlations with ‘emotional control’ (r=0.518; P<0.001), and ‘emotional control’ had a positive predictive effect on resilience (χ2=8.508; P<0.005). There were indications of positive correlations between resilience and ‘activation’ (r=0.497; P<0.001), ‘automaticity’ (r=0.437; P<0.001), and of a negative correlation between resilience and ‘negative thinking’ (r=-0.416; P<0.001). Overall CD-RISC-10 mean value was 29.96. ‘Activation’ and ‘automaticity’ were more applicable for riders of higher perceived levels of skill. Responses suggest that ‘activation’ was employed more frequently by male than female riders (Z=-2.118; P<0.05), and that ‘negative thinking’ was more frequent in female than male riders (Z=-1.969; P<0.05). More significant correlations between performance strategies were found in professional (19) than in novice riders (5). Results indicate that the use of performance strategies may be beneficial in the development of resilience. In higher level riders, the development of one set of strategies tends to lead to the development of other strategies. The findings support that the ability to recover successfully from adversities may not be merely inherent, but also under individual control.
Creating a CNE Audit Tool Using the Plan-Do-Study-Act Model
Authors: Little Susan Haynes , Busick Jana
Published: January 2019

The continuous performance-improvement model known as Plan-Do-Study-Act (PDSA) was used within the Approved Provider Unit of the North Carolina Division of Public Health to create an audit tool and process for assessing continuing nursing education courses. During the development of the audit tool, gaps and process inefficiencies were identified when documentation was reviewed for adherence to the American Nurses Credentialing Center's Commission on Accreditation's 2015 Criteria for Continuing Nursing Education and local provider unit requirements. This article traces the progress through three cycles of the PDSA model and provides the resulting audit tool and process. [
J Contin Educ Nurs.
2019;50(2):53–56.]
Outside-the-Box Skills Validation of Competency
Authors: Bennett Doris V.
Published: January 2019

The potential for harm to patients related to initiation and maintenance of continuous dialysis therapy by the bedside nurse led to the development of a novel method to educate nurses new to the skill of continuous renal replacement therapy. [
J Contin Educ Nurs.
2019;50(2):59–60.]
Automatic Sequences and Generalised Polynomials
Authors: Byszewski Jakub , Konieczny Jakub
Published: January 2019

We conjecture that bounded generalised polynomial functions cannot be generated by finite automata, except for the trivial case when they are ultimately periodic.

Using methods from ergodic theory, we are able to partially resolve this conjecture, proving that any hypothetical counterexample is periodic away from a very sparse and structured set. In particular, we show that for a polynomial$p(n)$with at least one irrational coefficient (except for the constant one) and integer$m\geqslant 2$, the sequence$\lfloor p(n)\rfloor \hspace{0.2em}{\rm mod}\hspace{0.2em}m$is never automatic.

We also prove that the conjecture is equivalent to the claim that the set of powers of an integer$k\geqslant 2$is not given by a generalised polynomial.
A Morita Cancellation Problem
Authors: Lu D.-M. , Wu Q.-S. , Zhang J. J.
Published: January 2019

We study a Morita-equivalent version of the Zariski cancellation problem.
The Weak Order on Weyl Posets
Authors: Gay Joël , Pilaud Vincent
Published: January 2019

We define a natural lattice structure on all subsets of a finite root system that extends the weak order on the elements of the corresponding Coxeter group. For crystallographic root systems, we show that the subposet of this lattice induced by antisymmetric closed subsets of roots is again a lattice. We then study further subposets of this lattice that naturally correspond to the elements, the intervals, and the faces of the permutahedron and the generalized associahedra of the corresponding Weyl group. These results extend to arbitrary finite crystallographic root systems the recent results of G. Chatel, V. Pilaud, and V. Pons on the weak order on posets and its induced subposets.
Degenerations of Leibniz and Anticommutative Algebras
Authors: Ismailov Nurlan , Kaygorodov Ivan , Volkov Yury
Published: January 2019

We describe all degenerations of three-dimensional anticommutative algebras $\mathfrak{A}\mathfrak{c}\mathfrak{o}\mathfrak{m}_{3}$ and of three-dimensional Leibniz algebras $\mathfrak{L}\mathfrak{e}\mathfrak{i}\mathfrak{b}_{3}$ over $\mathbb{C}$. In particular, we describe all irreducible components and rigid algebras in the corresponding varieties.
Orlicz–Besov Extension and Imbedding
Authors: Sun Hongyan
Published: January 2019

We establish criteria for Orlicz–Besov extension/imbedding domains via (global) $n$-regular domains that generalize the known criteria for Besov extension/imbedding domains.
Linear Conjugacy
Authors: Steinberg Benjamin
Published: January 2019

We say that two elements of a group or semigroup are $\Bbbk$-linear conjugates if their images under any linear representation over $\Bbbk$ are conjugate matrices. In this paper we characterize $\Bbbk$-linear conjugacy for finite semigroups (and, in particular, for finite groups) over an arbitrary field $\Bbbk$.
The Cholera Phone: Diarrheal Disease Surveillance by Mobile Phone in Bangladesh
Authors: Carstensen Leela Sengupta , Tamason Charlotte Crim , Sultana Rebeca , Tulsiani Suhella Mohan , Phelps Matthew David , Gurley Emily Suzanne , Jensen Peter Kjær Mackie
Published: January 2019

Existing methodologies to record diarrheal disease incidence in households have limitations due to a high-episode recall error outside a 48-hour window. Our objective was to use mobile phones for reporting diarrheal episodes in households to provide real-time incidence data with minimum resource consumption and low recall error. From June 2014 to June 2015, we enrolled 417 low-income households in Dhaka, Bangladesh, and asked them to report diarrheal episodes to a call center. A team of data collectors then visited persons reporting the episode to collect data. In addition, each month, the team conducted in-home surveys on diarrhea incidence for a preceding 48-hour period. The mobile phone surveillance reported an incidence of 0.16 cases per person-year (95% CI: 0.13–0.19), with 117 reported diarrhea cases, and the routine in-home survey detected an incidence of 0.33 cases per person-year (95% CI: 0.18–0.60), the incidence rate ratio was 2.11 (95% CI: 1.08–3.78). During focus group discussions, participants reported a lack in motivation to report diarrhea by phone because of the absence of provision of intervening treatment following reporting. Mobile phone technology can provide a unique tool for real-time disease reporting. The phone surveillance in this study reported a lower incidence of diarrhea than an in-home survey, possibly because of the absence of intervention and, therefore, a perceived lack of incentive to report. However, this study reports the untapped potential of mobile phones in monitoring infectious disease incidence in a low-income setting.
Perspectivas teóricas do reconhecimento de identidades sexuais frente aos direitos humanos e ao direito fraterno
Authors: Colet Gimenez Charlise Paula , Magalhães Martins Paulo Adroir , Angelin Rosângela
Published: January 2019

As identidades ganham significados nos contextos sociais. Desse modo, a partir de um estudo hipotético-dedutivo, pretende-se refletir acerca da importância do reconhecimento identitário das sexualidades para efetivar direitos humanos, apresentando-se as contribuições e os limites do Direito Fraterno sobre esse tema. Percebe-se que o reconhecimento identitário sexual evoluiu em termos jurídicos, mas segue envolto de preconceitos e estereótipos, refletindo na promoção e no exercício desses direitos. O Direito Fraterno contribui para reflexões das realidades a partir de premissas voltadas para a alteridade, o que facilita o reconhecimento de identidades sexuais não heteronormativas, muito embora seja necessário promover uma profunda mudança cultural.
Trends in surface radiation and cloud radiative effect at four Swiss sites for the 1996–2015 period
Authors: Nyeki Stephan , Wacker Stefan , Aebi Christine , Gröbner Julian , Martucci Giovanni , Vuilleumier Laurent
Published: January 2019

Abstract. The trends of meteorological parameters and surface downward shortwave and longwave radiation (DSR, DLR) were analyzed at four stations (between 370 and 3580 m asl) in Switzerland for the 1996–2015 period. Ground temperature, specific humidity and atmospheric integrated water vapor (IWV) increased during all-sky and cloud-free conditions. All-sky DSR and DLR trends were in the ranges 0.6–4.3 W m−2/decade and 0.9–4.3 W m−2/decade, respectively, while corresponding cloud-free trends were −2.9–3.3 W m−2/decade and 2.9–5.4 W m−2/decade. The cloud radiative effect (CRE) was determined using radiative transfer calculations for cloud-free DSR and an empirical scheme for cloud-free DLR. CRE decreased in magnitude by 0.9–3.1 W m−2/decade which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites. Between 10 and 70 % of the increase in DLR is explained by factors other than ground temperature and IWV. Trends in aerosol optical depth at each station over the same period remained insignificant, and thus their contribution to the observed changes in surface radiative fluxes was negligible. A more detailed, long-term quantification of cloud changes is crucial and will be possible in the future as cloud cameras have been measuring at three of the four stations since 2013.
Aerosol-radiation feedback deteriorates the wintertime haze in North China Plain
Authors: Wu Jiarui , Bei Naifang , Hu Bo , Liu Suixin , Zhou Meng , Wang Qiyuan , Li Xia , Liu Lang , Feng Tian , Liu Zirui , Wang Yichen , Cao Junji , Tie Xuexi , Wang Jun , Molina Luisa T. , Li Guohui
Published: January 2019

Abstract. Atmospheric aerosols or fine particulate matters (PM2.5) scatter or absorb a fraction of the incoming solar radiation to cool or warm the atmosphere, decreasing surface temperature and altering atmospheric stability to further affect the dispersion of air pollutants in the planetary boundary layer (PBL). In the present study, simulations during a persistent and heavy haze pollution episode from 05 December 2015 to 04 January 2016 in the North China Plain (NCP) were performed using the WRF-CHEM model to comprehensively quantify contributions of the aerosol shortwave radiative feedback (ARF) to near-surface PM2.5 mass concentrations. The WRF-CHEM model generally performs well in simulating the temporal variations and spatial distributions of air pollutants concentrations compared to observations at ambient monitoring sites in NCP, and the simulated diurnal variations of aerosol species are also consistent with the measurements in Beijing. Additionally, the model simulates well the aerosol radiative properties, the downward shortwave flux, and the PBL height against observations in NCP during the episode. During the episode, the ARF deteriorates the haze pollution, increasing the near-surface PM2.5 concentration in NCP by 10.2 μg m−3 or with a contribution of 7.8 %. Sensitivity studies have revealed that high loadings of PM2.5 during the episode attenuate the incoming solar radiation down to the surface, cooling the temperature of the low-level atmosphere to suppress development of PBL and decrease the surface wind speed, further enhancing the relative humidity and hindering the PM2.5 dispersion and consequently exacerbating the haze pollution in NCP. The ensemble analysis indicates that when the near-surface PM2.5 mass concentration increases from around 50 to several hundred μg m−3, the ARF contributes to the near-surface PM2.5 by more than 20 % during daytime in NCP, substantially aggravating the heavy haze formation. However, when the near-surface PM2.5 concentration is less than around 50 μg m−3, the ARF generally reduces the near-surface PM2.5 concentration due to the consequent perturbation of atmospheric dynamic fields.
New particle formation from sulfuric acid and ammonia: nucleation and
growth model based on thermodynamics derived from CLOUD
measurements for a wide range of conditions
Authors: Kürten Andreas
Published: January 2019

Abstract. Understanding new particle formation and growth is important because of the strong impact of these processes on climate and air quality. Measurements to elucidate the main new particle formation mechanisms are essential; however, these mechanisms have to be implemented in models to estimate their impact on the regional and global scale. Parameterizations are computationally cheap ways of implementing nucleation schemes in models but they have their limitations, as they do not necessarily include all relevant parameters. Process models using sophisticated nucleation schemes can be useful for the generation of look-up tables in large-scale models or for the analysis of individual new particle formation events. In addition, some other important properties can be derived from a process model that implicitly calculates the evolution of the full aerosol size distribution, e.g., the particle growth rates. Within this study, a model (SANTIAGO, Sulfuric acid Ammonia NucleaTIon And GrOwth model) is constructed that simulates new particle formation starting from the monomer of sulfuric acid up to a particle size of several hundred nanometers. The smallest sulfuric acid clusters containing one to four acid molecules and varying amount of base (ammonia) are allowed to evaporate in the model, whereas growth beyond the pentamer (5 sulfuric acid molecules) is assumed to be entirely collision-controlled. The main goal of the present study is to derive appropriate thermodynamic data needed to calculate the cluster evaporation rates as a function of temperature. These data are derived numerically from CLOUD (Cosmics Leaving OUtdoor Droplets) chamber new particle formation rates for neutral sulfuric acid-water-ammonia nucleation at temperatures between 208 K and 292 K. The numeric methods include an optimization scheme to derive the best estimates for the thermodynamic data (dH and dS) and a Monte Carlo method to derive their probability density functions. The derived data are compared to literature values. Using different data sets for dH and dS in SANTIAGO detailed comparison between model results and measured CLOUD new particle formation rates is discussed.
Precipitation δ18O on the Himalaya–Tibet orogeny and its relationship to surface elevation
Authors: Shen Hong , Poulsen Christopher J.
Published: January 2019

Abstract. The elevation history of the Himalaya–Tibet orogen is central to
understanding the evolution and dynamics of both the India–Asia collision
and the Asian monsoons. The surface elevation history of the region is
largely deduced from stable isotope (δ18O, δD)
paleoaltimetry. This method is based on the observed relationship between the
isotopic composition of meteoric waters (δ18Op,
δDp) and surface elevation, and the assumption that
precipitation undergoes Rayleigh distillation under forced ascent. Here we
evaluate how elevation-induced climate change influences the
δ18Op–elevation relationship and whether Rayleigh
distillation is the dominant process affecting
δ18Op. We use an isotope-enabled climate model,
ECHAM-wiso, to show that the Rayleigh distillation process is only dominant
in the monsoonal regions of the Himalayas when the mountains are high. When
the orogen is lowered, local surface recycling and convective processes
become important, as forced ascent is weakened due to weaker Asian monsoons.
As a result, the δ18Op lapse rate in the Himalayas
increases from around −3 to above −0.1 ‰ km−1, and has little
relationship with elevation. On the Tibetan Plateau, the meridional gradient
of δ18O decreases from ∼1 to
∼0.3 ‰ ∘−1 with reduced elevation, primarily due to
enhanced sub-cloud reevaporation under lower relative humidity. Overall, we
report that using δ18Op or
δDp to deduce surface elevation change in the
Himalayan–Tibetan region has severe limitations and demonstrate that the
processes that control annual-mean precipitation-weighted
δ18Op vary by region and with surface elevation.
In summary, we determine that the application of
δ18O paleoaltimetry is only appropriate for 7 of the 50 sites
from which δ18O records have been used to infer past elevations.
New insights on the predisposing factors and geomorphic response to the largest landslide on emerged Earth surface: the Seymareh rock slide - debris avalanche (Zagros Mts., Iran)
Authors: Delchiaro Michele , Della Seta Marta , Martino Salvatore , Dehbozorgi Maryam , Nozaem Reza
Published: January 2019

Abstract. The Seymareh landslide, detached ~ 10 ka from the north-eastern flank of the Kabir-kuh fold (Zagros Mts., Iran), is worldwide recognized as the largest massive rock slope failure (44 Gm3) ever recorded on the emerged Earth surface. Understanding the hazard conditions and the risk associated to this out-of-scale event would provide important pin points for risk mitigation strategies in case of extreme landslide scenarios. Controversial theories have been proposed so far by the scientific community to explain the generation of such an exceptional event and different scenarios have been proposed for explaining the induced changes of landscape. This study provides new constraints to the evolution of the Seymareh river valley, before and after the Seymareh landslide occurrence, to correctly identify the predisposing factors, to suggest possible triggers and deduce the geomorphic response to the slope failure. We performed detailed geological and geomorphological surveys and mapping of the Seymareh valley and dated with optically stimulated luminescence (OSL) two suites of fluvial terraces (one older and one younger than the Seymareh landslide) as well as a lacustrine terrace (formed after the temporary landslide damming), as useful geomorphic markers of the valley evolution. River profile metrics showed the evidence of a transient landscape and the plano-altimetric distribution of the geomorphic markers has been correlated to the detectable knickpoints along the Seymareh river longitudinal profile. We thus provide time constraints to the main evolutionary stages of the valley before and after the emplacement of the landslide, to be used as inputs for future stress-strain time-dependent numerical modelling in the perspective of calibrating the rock mass viscosity and verifying the possible earthquake trigger of the Seymareh landslide as an ultimate scenario of ongoing mass rock creep processes.
Distinct Element geomechanical modelling of the formation of sinkhole cluster within large-scale karstic depressions
Authors: Al-Halbouni Djamil , Holohan Eoghan P. , Taheri Abbas , Watson Robert A. , Polom Ulrich , Schöpfer Martin P. J. , Emam Sacha , Dahm Torsten
Published: January 2019

Abstract. The 2D Distinct Element Method (DEM) code (PFC2D_V5) is here used to simulate the evolution of subsidence-related karst landforms, such as single and clustered sinkholes, and associated larger-scale depressions. Subsurface material in the DEM model is removed by a feedback loop to produce an array of cavities; this simulates a network of subsurface groundwater conduits growing by chemical/mechanical erosion. The growth of the cavity array is coupled mechanically to the surroundings such that cavities can grow also in part by material failure at their margins, which in the limit can produce individual collapse sinkholes. Two end-member growth scenarios of the cavity array and their impact on surface subsidence were examined in the models: (1) cavity growth at the same level and at the same individual growth rate; (2) cavity growth at progressively deepening levels with varying individual growth rates. These growth scenarios are characterised by differing stress patterns across the cavity array and its overburden, which are in turn an important factor for the formation of sinkholes and uvala-like depressions. For growth scenario (1), a stable compression arch is established around the cavity array, hindering sinkhole collapse into individual cavities and favouring block-wise subsidence across the whole cavity array. In contrast, for growth scenario (2), the stress system is more heterogeneous, such that local stress concentrations exist around individual cavities leading to stress interaction. Consequently, sinkhole collapses into individual cavities occurs by shear or tensile failure of the overburden, and these sinkholes lie within a larger scale depression linked to the cavity array as a whole. The results from models with growth scenario (2), which also account for variations in mechanical properties of the overburden, are in close agreement with surface morphological and subsurface geophysical observations from a karst area on the eastern shore of the Dead Sea.
Word embeddings for application in geosciences: development, evaluation and examples of soil-related concepts
Authors: Padarian José , Fuentes Ignacio
Published: January 2019

Abstract. A large amount of descriptive information is available in most disciplines of geosciences. This information is usually considered subjective and ill-favoured compared with its numerical counterpart. Considering the advances in natural language processing and machine learning, it is possible to utilise descriptive information and encode it as dense vectors. These word embeddings lay on a multi-dimensional space where angles and distances have a linguistic interpretation. We used 280 764 full-text scientific articles related to geosciences to train a domain-specific language model capable of generating such embeddings. To evaluate the quality of the numerical representations, we performed three intrinsic evaluations, namely: the capacity to generate analogies, term relatedness compared with the opinion of a human subject, and categorisation of different groups of words. Since this is the first attempt to evaluate word embedding for tasks in the geosciences domain, we created a test suite specific for geosciences. We compared our results with general domain embeddings commonly used in other disciplines. As expected, our domain-specific embeddings (GeoVec) outperformed general domain embeddings in all tasks, with an overall performance improvement of 107.9 %. The resulting embedding and test suite will be made available for other researchers to use an expand.
Transferring land use rights with transportation infrastructure extensions: Evidence on spatiotemporal price formation in Shanghai
Authors: Chang Zheng , Murakami Jin
Published: January 2019

To address the efficiency and sustainability of residential suburbanization under state leasehold systems, this study examines the price formation of long-term land-use rights for general and compensational housing empirically, considering the successive expansions of new metro lines and highway networks during 2004–2016 in Shanghai—one of the world’s fastest growing megacities. The results of our spatial autoregressive models infer that the accessibility benefits of metro extensions are considerably capitalized into both the ask and transaction prices of land-use rights for general housing in the suburbs, whereas those for highway construction are insignificant. A series of spatiotemporal regressions demonstrate that the premiums for proximity to new metro stations bid by private developers are much higher than those asked by local governments during pre-metro years, probably due to local governments’ strategic site arrangements for transit-oriented suburbanization and/or developers’ speculative land acquisitions in Shanghai’s upward suburban housing market. This study further reveals that the prices of land-use rights for compensational housing do not reflect any economic externalities attributable to metro stations and highway interchanges, which might trigger the unfair redistribution of property rights, accessibility, and economic opportunities among relocated farmers around city-fringe areas.
Western Faculty Profile: Dr. Art Poon
Authors: Zhao Jonathan
Published: January 2019

Dr. Art Poon is an Assistant Professor in the Department of Pathology and Laboratory Medicine at Western University. Dr. Poon has a background in mathematical biology and obtained a doctorate in bioinformatics at the University of California in San Diego. His research focus is on designing and implementing new computational methods to reconstruct the spread and adaptation of viruses from their genetic sequence variation. Jonathan Zhao had the pleasure of interviewing Dr. Poon to learn more about his career path and his research.
EVALUTION OF RISK FACTORS AND SEROPREVALENCE RATE OF TOXOPLASMOSIS IN THE ELDERLY
Authors: De Lima Marina Saint Clair Mattioda , Oliveira Beatriz Campos , Barbosa Naiane Moreira , Silveira Murilo Barros , Guerra Heloísa Silva , Rezende Hânstter Hállison Alves , De Castro Ana Maria , Avelar Juliana Boaventura
Published: January 2019

Toxoplasmosis is an infection caused by the protozoan Toxoplasma gondii, whose definitive hosts are cats and whose intermediate hosts include humans.This research aims to evaluate aspects related to seroprevalence rates of anti-T. gondii antibodies among elderly users of the Primary Health Care Service in the municipality of Aparecida de Goiânia, state of Goiás, Brazil. A total of 101 elderly people participated in the study, and a questionnaire was applied to examine sociodemographic factors related to risk factors for toxoplasmosis. Five ml of peripheral blood were collected from all the participants for serological tests. IgM and IgG antibody screening was performed using the ELISA technique. The average age of the participants was 69.5 years, the seroprevalence rate was 75.2% (76/101) of IgG (+), and 24.8% (25/101) were non-reactive. IgM and IgG antibodies were found in 2.9% (3/101) of the participants. An IgG avidity test was performed, which revealed that the antibodies in the three samples were of low avidity, thus indicating that these individuals were in the acute phase of the infection. It was concluded that, in terms of socioeconomic conditions, an income of one to three monthly minimum salaries is the predominant risk factor for toxoplasmosis in this group.
OCCURRENCE OF INTESTINAL PARASITES IN COLLECTORS OF RECYCLABLE MATERIALS IN SOUTHERN BRAZIL
Authors: Azevedo Sposito Nathalia , Leal Sperotto Rita , Lidiane Guidotti Aguiar Cíntia , Machado Carvalho Aline , Da Silva Brenda , Amelia da Rosa Farias Nara
Published: January 2019

Solid waste produced by modern society, together with lack of basic sanitation and poor hygiene practices result in risks to public health. 46 workers from the cities of Pelotas, Canguçu, Morro Redondo, Rio Grande and Capão do Leão were evaluated by parasitological examination of two fecal samples by Ritchie, Hoffman, Pons and Janer- HPJ techniques and Sheather method as well as a consented interview. 47.8% (22/46) of the examined individuals were parasitized, with no significant difference between both groups (garbage dump and recycling volunteers). Most of the samples evaluated presented forms of helminths (68.2%) while protozoa were found in 31.8% of the samples. Helminths found, and their respective prevalence were: Ascaris lumbricoides (31.8%), Ascaris lumbricoides/Trichuris trichiura (18.2%), Trichuris trichiura (9.1%), Taenia sp (4.6%) and Trichuris trichiura/Ancylostomids (4.6%). Protozoa were: Giardia intestinalis (13, 6%), Entamoeba spp. (9.1%) and Endolimax nana (9.1%). Monoparasitism was observed in 77.3% of the cases. Most of the population consisted of women, 21-40 years of age, low educational level and monthly income less than one minimum wage. The majority of the workers did not use protective equipment. Multivariate analysis revealed that infection from parasites in scavengers who lived near open sewers was 6.65 times higher (p = 0.0065) than in the other workers. In the localities studied, our results showed that the risk of acquiring parasitic infections was related to poor sanitation and the lack of sewerage systems; and not actually due to handling these types of waste. The parasitological indices found are similar to those described previously in other parts of the country.
Consumers´ awareness of food safety
Authors: Nagyová Ľudmila , Andocsová Alexandra , Géci Andrej , Zajác Peter , Palkovič Jozef , Košičiarová Ingrida , Golian Jozef
Published: January 2019

Eating food is one of the most important needs of every person, so their safety and quality should be crucial for everyone. People expect, that food they eat is hygienically and health safe. Unfortunately, people usually start to focus on food safety only when various food scandals are exposed and it is too late. Mass consumption of food is the cause of a high risk to human health, but only in the case of harmful food. Food-borne diseases are a common and widespread phenomenon in all parts of the world, regardless of the economic development of the country. Protection of human, animal and plant health is one of the main economic priorities of each country. The political objective of the European Union is therefore to ensure that European Union citizens have access to safe and nutritious foods, so it must meet strict safety standards. In ensuring food safety, it is necessary to take into account all aspects of the food production chain as a whole, because each subject can have a potential impact on food safety. This paper deals with the issues of food safety and food quality. The main objective was to find out how consumers perceive higher quality food and whether they read information included on the food packaging. Primary data were obtained from a survey that was conducted on the sample of 478 respondents living in Slovakia. For a deeper analysis, several assumptions, which were verified by Friedman Test, Chi-Square Test of Independence, Wilcoxon Signed-Rank Test, were formulated. The survey has found out that 84% of respondents buy higher quality food and 60% purchase them because of health-related reasons. More than half of respondents search for the information about food safety on the Internet and the same percentage considere government as the most reliable source of information about food safety. Unfortunately, just more than one quarter of them read the information on food label and for 34% is this information unsufficient.