bluuebunny/crossref_metadata_2025 huggingface dataset:
Deciphering the mechanistic effects of eIF4E phosphorylation on mRNA‐cap recognition
Authors: Lama Dilraj , Verma Chandra S.
Published: December 2019

The mRNA cap‐binding oncoprotein “eIF4E” is phosphorylated at residue S209 by Mnk kinases, and is closely associated with tumor development and progression. Despite being well‐established, mechanistic details at the molecular level of mRNA recognition by eIF4E due to phosphorylation have not been clearly elucidated. We investigated this through molecular modeling and simulations of the S209 phosphorylated derivative of eIF4E and explored the associated implication on the binding of the different variants of mRNA‐cap analogs. A key feature that emerges as a result of eIF4E phosphorylation is a salt‐bridge network between the phosphorylated S209 (pS209) and a specific pair of lysine residues (K159 and K162) within the cap‐binding interface on eIF4E. This interaction linkage stabilizes the otherwise dynamic C‐terminal region of the protein, resulting in the attenuation of the overall plasticity and accessibility of the binding pocket. The pS209‐K159 salt‐bridge also results in an energetically less favorable environment for the bound mRNA‐cap primarily due to electrostatic repulsion between the negative potentials from the phosphates in the cap and those appearing as a result of phosphorylation of S209. These observations collectively imply that the binding of the mRNA‐cap will be adversely affected in the phosphorylated derivative of eIF4E. We propose a mechanistic model highlighting the role of eIF4E phosphorylation as a regulatory tool in modulating eIF4E: mRNA‐cap recognition and its potential impact on translation initiation.
Therapeutic efficacy of hepatitis B virus vaccine in treatment of chronic HBV infections: A systematic review and meta‐analysis
Authors: Ghozy Sherief , Nam Nguyen Hai , Radwan Ibrahim , Karimzadeh Sedighe , Tieu Thuan Minh , Hashan Mohammad Rashidul , Abbas Alzhraa Salah , Eid Peter Samuel , Vuong Nguyen Lam , Khang Nguyen Vinh , Elgabalawy Eman , Sayed Ahmed Kamal , Hoa Pham Thi Le , Huy Nguyen Tien
Published: December 2019

There is a need for improved treatment of patients with chronic hepatitis B (CHB). We reviewed the literature to explore the efficacy of HB vaccines alone or in combination therapy (CT) with antiviral drugs in CHB patients and to meta‐analyze data from randomized controlled trials. We conducted a systematic search in ten databases. All studies investigating the efficacy of HBV vaccine in HBV infected patients were included with no restrictions. Among 1359 studies initially identified, 23 studies (n = 1956 patients) were included for the final analysis. CT showed a significant reduction of HBV DNA compared with analogue monotherapy (AM) at the 12‐month follow‐up period (odds ratio (OR) = 2.835, 95% confidence interval (CI) [1.275, 6.306], p = .011). Additionally, CT also remarkably induce HbsAg loss in comparison with AM (OR = 11.736, 95% CI [1.841, 74.794], p = .009). Our pooled data revealed no difference between treatment and control regarding alanine aminotransferase normalization, HBeAg seroconversion, and HBeAg disappearance. In addition, CT using vaccine and NAs resulted in a statistically significant higher incidence of adverse effects than AM. The therapeutic effects of combination therapy for patients with CHB were encouraging, but future studies need to investigate all possible treatment combinations and assess their cost‐effectiveness.
Anti‐windup design of active disturbance rejection control for sampled systems with input delay
Authors: Geng Xinpeng , Liu Tao , Hao Shoulin , Zhong Chongquan , Wang Qing‐Guo
Published: December 2019

A novel anti‐windup design of active disturbance rejection control (ADRC) is proposed for industrial sampled systems with input delay and saturation. By using a generalized predictor to estimate the delay‐free system output, a modified extended state observer is designed to simultaneously estimate the system state and disturbance, which could become an anti‐windup compensator when the input saturation occurs. Accordingly, a feedback controller is analytically designed for disturbance rejection. By proposing the desired closed‐loop transfer function for the set‐point tracking, a prefilter is designed to tune the tracking performance while guaranteeing no steady‐state output tracking error. A sufficient condition for the closed‐loop system stability is established with proof for practical application subject to the input delay variation. Illustrative examples from the literature are used to demonstrate the effectiveness and merit of the proposed control design.
Experimental and modeling study on the progressive collapse resistance of a reinforced concrete frame structure under a middle column removal scenario
Authors: Zhang Qiang , Li Yaozhuang
Published: December 2019

A reinforced concrete (RC) frame structure is one of the widely used structural system. A localized damage caused by extreme events may lead to progressive collapse of entire structures. In this paper, progressive collapse test of three 1/3‐scaled reinforced concrete frame, including a single‐story without a slab, single‐story with a slab, and double‐story with slabs, are reported. Experimental results show that the progressive collapse process of RC frame consisted of five stages: an elastic stage, yield stage, beam mechanism stage, transient stage and catenary stage. The reinforced concrete slabs contribute to large progressive collapse resistance force compared with the specimen without slab. Furthermore, validation of the test results by using a refined solid finite element model was established. The effect of extensive parameters, including slab thickness, beam section height, seismic design intensity, and so forth, on the progressive collapse performance of RC frame structures was simulated as well. The simulation results indicated that the collapse resistance of RC structures was substantially improved with the increased of the slab thickness and seismic design intensity. Finally, a simplified model is proposed in accordance with experimental and numerical results to calculate the collapse resistance of RC frame structures.
Probabilistic risk assessment on wind turbine towers subjected to cyclone‐induced wind loads
Authors: Jaimes Miguel A. , García‐Soto A. David , Martín del Campo J. Osvaldo , Pozos‐Estrada Adrián
Published: December 2019

A probabilistic risk assessment to estimate the economic impact on wind turbine towers subjected to cyclone‐induced wind loads is applied. An event‐based probabilistic framework is used to assess the risk parameters for selected hazard events. The results are integrated considering all uncertainties related to each part of the process in a probabilistic formal way. The hazard is defined by a set of nonoverlapping stochastic events that exhaust the considered sample space, including the spatial distribution, the annual frequency, and the randomness of the hazard intensity. The vulnerability is defined in terms of the first and second statistical moments: the expected damage and its corresponding variance (or standard deviation) for a certain type of wind turbine towers. The vulnerability component of the model is an important contribution of the study; it uses a realistic modeling of the wind field, and instead of one (as in other studies), three failure modes are considered to characterize the vulnerability. The risk is expressed in economic terms, namely, the single‐event expected loss, the average annual loss, the pure premium, and the loss exceedance curve. The approach is applied to a probabilistic tropical cyclone wind risk assessment on 3001 wind turbine towers from 65 wind farms in Mexico. It is concluded that the selected metrics are of especial importance for risk retention (financing), particularly if schemes or risk transfer instruments are to be defined, and therefore, they will be a very valuable contribution to further studies in defining strategies for financial protection of national infrastructure against wind disasters induced by cyclones.
Investigating the role of organic carbon amendments and microbial denitrification gene abundance in nitrogen removal from experimental agricultural drainage ditches with low‐grade weirs
Authors: Faust Derek R. , Kröger Robert , Baker Beth H. , Brooks John P. , Cox Michael S. , Rush Scott A.
Published: December 2019

Low‐grade weirs placed within agricultural drainage ditches in the Lower Mississippi Alluvial Valley can be used as a management practice to enhance nitrogen removal. The addition of organic carbon amendments within ditches that contain weirs could further increase nitrogen removal. Through repeated trials, changes in ‐N concentration between inflow and outflow were variable in the ditch without weirs, while only decreases in concentration were observed in ditches with weirs. Significant differences in ‐N concentrations were observed between treatments, with greater removal of ‐N observed in dissolved organic carbon treatments compared to control and particulate organic carbon treatments. At medium‐ and high‐flow rates, respectively, dissolved organic carbon treatments resulted in greater ‐N concentration decreases of 31.6% and 27.1% compared to 19% and 11.6% in particulate organic carbon treatments and 18.6% and 17.2% in control treatments. Significant effects of weirs and sampling date on nirS, nirK, nosZ, and 16S rRNA gene abundances were observed. Observed increases in ‐N removal with organic carbon amendments, provides support for continued investigation on improving the efficacy of organic carbon amendments as a best management practice for ‐N removal in agricultural drainage ditches.

Practitioner points

Dissolved organic carbon amendments increased nitrate–nitrogen removal.

Only decreases in nitrate–nitrogen concentration were observed in ditches with weirs.

Increasing flow rate did not affect nitrate–nitrogen removal.

Abundance of denitrification‐performing microbes likely did not affect N removal.

Lack of anaerobic soil conditions and short residence time reduced nitrate‐N removal.
Modular S4 and A4 symmetries and their fixed points: new predictive examples of lepton mixing
Authors: Ding Gui-Jun , King Stephen F. , Liu Xiang-Gan , Lu Jun-Nan
Published: December 2019

Abstract

In the modular symmetry approach to neutrino models, the flavour symmetry emerges as a finite subgroup Γ
N
of the modular symmetry, broken by the vacuum expec- tation value (VEV) of a modulus field τ. If the VEV of the modulus τ takes some special value, a residual subgroup of Γ
N
would be preserved. We derive the fixed points τ

S
= i, τ

ST
= (−1 + i

$$ \sqrt{3} $$

3

)/2, τ

TS
= (1 + i

$$ \sqrt{3} $$

3

)/2, τ

T
= i∞ in the fundamental domain which are in-variant under the modular transformations indicated. We then generalise these fixed points to τ

f
= γτ

S
, γτ

ST
, γτ

TS
and γτ

T
in the upper half complex plane, and show that it is suffi-cient to consider γ ∈ ΓN. Focussing on level N = 4, corresponding to the flavour group S
4, we consider all the resulting triplet modular forms at these fixed points up to weight 6. We then apply the results to lepton mixing, with different residual subgroups in the charged lepton sector and each of the right-handed neutrinos sectors. In the minimal case of two right-handed neutrinos, we find three phenomenologically viable cases in which the light neutrino mass matrix only depends on three free parameters, and the lepton mixing takes the trimaximal TM1 pattern for two examples. One of these cases corresponds to a new Littlest Modular Seesaw based on CSD(n) with n = 1 +

$$ \sqrt{6} $$

6

≈ 3.45, intermediate between CSD(3) and CSD(4). Finally, we generalize the results to examples with three right-handed neutrinos, also considering the level N = 3 case, corresponding to A
4 flavour symmetry.
Calculating pull for non-singlet jets
Authors: Bao Yunjia , Larkoski Andrew J.
Published: December 2019

Abstract

The pull vector is a jet observable sensitive to the distribution of soft radiation controlled by the color flow in a collider event. We present calculations to leading order in the soft and collinear limits for the pull vector measured between pairs of jets that do not form a color-singlet dipole. Our calculations are presented within the context of e
+
e

−

→ three jets events, on which pull is measured between the two subleading jets. A subset of these calculations can be re-interpreted as a bottom-anti-bottom quark jet pair in a color octet configuration, which can be a background to Higgs production at large boost. We also present a universal expression for the pull distribution in the high-boost and small jet radius limit. This distribution is controlled by color SU(3) quadratic Casimirs that arise from product representations of pairs of QCD jets.
Master equations and stability of Einstein-Maxwell-scalar black holes
Authors: Jansen Aron , Rostworowski Andrzej , Rutkowski Mieszko
Published: December 2019

Abstract

We derive master equations for linear perturbations in Einstein-Maxwell scalar theory, for any spacetime dimension D and any background with a maximally symmetric n = (D - 2)-dimensional spatial component. This is done by expressing all fluctuations analytically in terms of several master scalars. The resulting master equations are Klein­ Gordon equations, with non-derivative couplings given by a potential matrix of size 3, 2 and 1 for the scalar, vector and tensor sectors respectively. Furthermore, these potential matrices turn out to be symmetric, and positivity of the eigenvalues is sufficient (though not necessary) for linear stability of the background under consideration. In general these equations cannot be fully decoupled, only in specific cases such as Reissner-Nordstrom, where we reproduce the Kodama-Ishibashi master equations. Finally we use this to prove stability in the vector sector of the GMGHS black hole and of Einstein-scalar theories in general.
Holographic fundamental matter in multilayered media
Authors: Gran Ulf , Jokela Niko , Musso Daniele , Ramallo Alfonso V. , Tornsö Marcus
Published: December 2019

Abstract

We describe a strongly coupled layered system in 3+1 dimensions by means of a top-down D-brane construction. Adjoint matter is encoded in a large-N

c
stack of D3-branes, while fundamental matter is confined to (2 + 1)-dimensional defects introduced by a large-N

f
stack of smeared D5-branes. To the anisotropic Lifshitz-like background geometry, we add a single flavor D7-brane treated in the probe limit. Such bulk setup corresponds to a partially quenched approximation for the dual field theory. The holographic model sheds light on the anisotropic physics induced by the layered structure, allowing one to disentangle flavor physics along and orthogonal to the layers as well as identifying distinct scaling laws for various dynamical quantities. We study the thermodynamics and the fluctuation spectrum with varying valence quark mass or baryon chemical potential. We also focus on the density wave propagation in both the hydrodynamic and collisionless regimes where analytic methods complement the numerics, while the latter provides the only resource to address the intermediate transition regime.
Effective estimates for the degrees of maximal special subvarieties
Authors: Daw Christopher , Javanpeykar Ariyan , Kühne Lars
Published: December 2019

Let Z be an algebraic subvariety of a Shimura variety. We extend results of the first author to prove an effective upper bound for the degree of a non-facteur maximal special subvariety of Z.
Allostasis and the origins of adult-onset diabetes
Authors: Leslie R. David , Vartak Tanwi
Published: December 2019

Physiological plasticity enables homeostasis to be maintained in biological systems, but when such allostasis fails, then disease can develop. In a new population-based study by Rolandsson et al (10.1007/s00125-019-05016-3), autoimmunity, defined by an immunogenotype, predicted adult-onset non-insulin requiring diabetes. Type 1 diabetes is no longer viewed as a disease confined to children, with a significant proportion, maybe the majority, presenting in adulthood. Such cases masquerade as type 2 diabetes and their identification has clinical utility. Nevertheless, in this study, autoimmunity had a limited effect on the overall risk of adults developing diabetes.
Cross-Sectional Associations Between Dietary Antioxidant Vitamins C, E and Carotenoid Intakes and Sarcopenic Indices in Women Aged 18–79 Years
Authors: Welch A. A. , Jennings A. , Kelaiditi E. , Skinner J. , Steves C. J.
Published: December 2019

The prevalence of sarcopenia is increasing in aging populations, so prevention is critical. Vitamins (A, C, E and carotenoids) modify skeletal muscle via protein and collagen synthesis and anti-inflammatory activities. Previous studies have not investigated intake of these vitamins in relation to sarcopenic indices in both younger and older-aged women. Indices of skeletal muscle mass (as fat-free mass (FFM) relative to body size) were measured using DXA and leg explosive power (LEP) using the Nottingham Power Rig in 2570 women aged 18–79 years. Adjusted measures of skeletal muscle were calculated according to quintiles of vitamin C, E, retinol and carotenoid intake, derived from Food Frequency Questionnaires, after stratification by age. Higher vitamin C intake was associated with significantly higher indices of FFM and LEP, (Q5-Q1 = 2.0–12.8%, P < 0.01–0.02). Intakes of total and individual carotenoids were significantly associated with indices of FFM and LEP (Q5-Q1 = 1.0–7.5%). Vitamin E was significantly associated with FFM% and FFMBMI only. In mutually adjusted analysis with vitamin C, total carotene, vitamin E and protein in the model, the strongest associations were with vitamin C. These associations were stronger in younger women (< 65 years). For the first time, our research shows higher dietary intakes of antioxidant vitamins, particularly vitamin C, is associated with higher skeletal muscle mass and power in free-living women. These findings have relevance for the treatment and prevention of frailty and sarcopenia throughout adulthood.
Structural and molecular characteristics of axons in the long head of the biceps tendon
Authors: Blumer Roland , Boesmueller Sandra , Gesslbauer Bernhard , Hirtler Lena , Bormann Daniel , Pastor Angel M. , Streicher Johannes , Mittermayr Rainer
Published: December 2019

The innervation of the long head of the biceps tendon (LHBT) is not sufficiently documented. This is a drawback since pathologies of the LHBT are a major source of shoulder pain. Thus, the study aimed to characterize structurally and molecularly nervous elements of the LHBT. The proximal part of 11 LHBTs was harvested intraoperatively. There were 8 female and 3 male specimens. Age ranged from 66 to 86 years. For structural analyses, nervous elements were viewed in the transmission electron microscope. For molecular characterization, we used general neuronal markers including antibodies against neurofilament and protein gene product 9.5 (PGP9.5) as well as specific neuronal markers including antibodies against myelin basic protein (MBP), calcitonin gene-related product (CGRP), substance P (SP), tyrosine hydroxylase (TH), and growth-associated protein 43 (GAP43). Anti-neurofilament and anti-PGP9.5 visualized the overall innervation. Anti-MBP visualized myelination, anti-CGRP and anti-SP nociceptive fibers, anti-TH sympathetic nerve fibers, and anti-GAP43 nerve fibers during development and regeneration. Immunolabeled sections were analyzed in the confocal laser scanning microscope. We show that the LHBT contains unmyelinated as well as myelinated nerve fibers which group in nerve fascicles and follow blood vessels. Manny myelinated and unmyelinated axons exhibit molecular features of nociceptive nerve fibers. Another subpopulation of unmyelinated axons exhibits molecular characteristics of sympathetic nerve fibers. Unmyelinated sympathetic fibers and unmyelinated nociceptive fibers express proteins that are found during development and regeneration. Present findings support the hypothesis that ingrowth of nociceptive fibers are the source of chronic tendon pain.
Extensometer forensics: what can the data really tell us?
Authors: Burbey Thomas J.
Published: December 2019

Extensometer data have an advantage over satellite-based data for monitoring land subsidence in that extensometer data provide continuous measurements (hourly or better temporal resolution) at very high precision (several tens of microns) over a known depth interval; the latter is important for isolating groundwater pumping from other causes of land subsidence attributed to tectonics or eustatic adjustments in the Earth’s crust. This investigation aims to identify a semi-analytical procedure for quantifying aquifer and aquitard properties from a single extensometer record in lieu of the time-consuming development of more complex numerical models to quantify and constrain these parameter values. In spite of a limited 12-year record and the fact that water levels both decline and increase on an annual basis, this study successfully and reasonably estimated both aquifer and aquitard parameters at the Lorenzi extensometer site in Las Vegas Valley, Nevada (USA), when compared to the estimates developed numerically. The key factors that allow for estimates of elastic and inelastic skeletal-specific storage and hydraulic conductivity of the aquitards and elastic specific storage and hydraulic conductivity of the intervening aquifers is the presence of pumping cycles at multiple frequencies, and measured heads at all the aquifer units covered in the extensometer record. There is an inherent assumption that the aquitards possess the same hydrologic characteristics and are homogeneous and isotropic. This assumption is also a usual limitation in numerical modeling of these settings because of the complex temporal head relationships occurring within the aquitards that are rarely, if ever, measured.
The effect of atomic point charges on adsorption isotherms of CO2 and water in metal organic frameworks
Authors: Sladekova Kristina , Campbell Christopher , Grant Calum , Fletcher Ashleigh J. , Gomes José R. B. , Jorge Miguel
Published: December 2019

The interactions between metal–organic frameworks (MOFs) and adsorbates have been increasingly predicted and studied by computer simulations, particularly by Grand-Canonical Monte Carlo (GCMC), as this method enables comparing the results with experimental data and also provides a degree of molecular level detail that is difficult to obtain in experiments. The assignment of atomic point charges to each atom of the framework is essential for modelling Coulombic interactions between the MOF and the adsorbate. Such interactions are important in adsorption of polar gases like water or carbon dioxide, both of which are central in carbon capture processes. The aim of this work is to systematically investigate the effect of varying atomic point charges on adsorption isotherm predictions, identify the underlying trends, and based on this knowledge to improve existing models in order to increase the accuracy of gas adsorption prediction in MOFs. Adsorption isotherms for CO2 and water in several MOFs were generated with GCMC, using the same computational parameters for each material except framework point charge sets that were obtained through a wide range of computational approaches. We carried out this work for 6 widely studied MOFs; IRMOF-1, MIL-47, UiO-66, CuBTC, Co-MOF-74 and SIFSIX-2-Cu-I. We included both MOFs with and without open metal sites (OMS), specifically to investigate whether this property affects the predicted adsorption behaviour. Our results show that point charges obtained from quantum mechanical calculations on fully periodic structures are generally more consistent and reliable than those obtained from either cluster-based QM calculations or semi-empirical approaches. Furthermore, adsorption in MOFs that contain OMS is much more sensitive to the point charge values, with particularly large variability being observed for water adsorption in such MOFs. This suggests that particular care must be taken when simulating adsorption of polar molecules in MOFs with open metal sites to ensure that accurate results are obtained.
Empirical fragility functions and loss curves for Italian business facilities based on the 2012 Emilia-Romagna earthquake official database
Authors: Rossi Leonardo , Stupazzini Marco , Parisi Davide , Holtschoppen Britta , Ruggieri Gabriella , Butenweg Christoph
Published: December 2019

The 2012 Emilia-Romagna earthquake, that mainly struck the homonymous Italian region provoking 28 casualties and damage to thousands of structures and infrastructures, is an exceptional source of information to question, investigate, and challenge the validity of seismic fragility functions and loss curves from an empirical standpoint. Among the most recent seismic events taking place in Europe, that of Emilia-Romagna is quite likely one of the best documented, not only in terms of experienced damages, but also for what concerns occurred losses and necessary reconstruction costs. In fact, in order to manage the compensations in a fair way both to citizens and business owners, soon after the seismic sequence, the regional administrative authority started (1) collecting damage and consequence-related data, (2) evaluating information sources and (3) taking care of the cross-checking of various reports. A specific database—so-calledSistema Informativo Gestione Europa(SFINGE)—was devoted to damaged business activities. As a result, 7 years after the seismic events, scientists can rely on a one-of-a-kind, vast and consistent database, containing information about (among other things): (1) buildings’ location and dimensions, (2) occurred structural damages, (3) experienced direct economic losses and (4) related reconstruction costs. The present work is focused on a specific data subset of SFINGE, whose elements are Long-Span-Beam buildings (mostly precast) deployed for business activities in industry, trade or agriculture. With the available set of data, empirical fragility functions, cost and loss ratio curves are elaborated, that may be included within existing Performance Based Earthquake Engineering assessment toolkits.
Factors affecting the occurrence and activity of clouded leopards, common leopards and leopard cats in the Himalayas
Authors: Can Özgün Emre , Yadav Bhupendra Prasad , Johnson Paul J. , Ross Joanna , D’Cruze Neil , Macdonald David W.
Published: December 2019

Clouded leopards are one of the least known of larger felids and were believed to be extinct in Nepal until 1987. They are particularly interesting because their Asian range spans a diversity of habitats in the fastest disappearing forests in the world and encompasses a guild which differs in composition from place to place. As a part of a wider camera-trapping study of this guild, involving 2948 camera traps at 45 sites in nine countries, and paralleling a similar study of the Sunda clouded leopard including a further 1544 camera traps spanning 22 sites distributed across two countries, we deployed 84 pairs of camera traps for 107 days in 2014 and 2015 at Langtang National Park, Nepal between 1823 and 3824 m a.s.l. within a grid encompassing c. 120 km2. We documented the presence of clouded leopards for the first time at an altitude as high as 3498 m a.s.l. Naïve occupancy for clouded leopard was 8.6% (correcting for detection, 10.1%). Clouded leopards were least active in the middle of the day, and largely crepuscular and nocturnal, as were the common leopards and leopard cats. The peak of clouded leopard activity overlapped with that of musk deer. Prey species for both clouded leopard and common leopard were available across the elevation range studied although the availability of some prey species declined as elevation increased, whereas Himalayan serow, Himalayan goral, and musk deer showed no association with elevation. Before this study, there was no hard evidence that clouded leopards occurred above 2300 m a.s.l., having documented them at almost 4000 m a.s.l. in the Himalayas, we emphasise the importance of this extreme portion of the species’ range where climate is likely to change more rapidly and with greater consequences, than the global average. The discovery of clouded leopards in Langtang National Park considerably extends their known range, and raises the possibility that they occur from the Terai in southern Nepal up to the Nepal-Tibet (China) border in the north. Insofar as this study has extended the known extreme boundary of the clouded leopard’s geographic range to encompass Langtang National Park in the Nepali Himalayas.
Ni–Zn–Al-Based Oxide/Spinel Nanostructures for High Performance, Methane-Selective CO2 Hydrogenation Reactions
Authors: Rajkumar T. , Sápi András , Ábel Marietta , Farkas Ferenc , Gómez-Pérez Juan Fernando , Kukovecz Ákos , Kónya Zoltán
Published: December 2019

In the present study, NiO modified ZnAl2O4 and ZnO modified NiAl2O4 spinel along with pure Al2O3, ZnAl2O4 and NiAl2O4 for comparison in the CO2 hydrogenation reaction have been investigated. It was found that NiAl2O4, NiO/ZnAl2O4 and ZnO/NiAl2O4 catalysts exhibited outstanding activity and selectivity towards methane even at high temperature compared to similar spinel structures reported in the literature. NiO/ZnAl2O4 catalyst showed CO2 consumption rate of ~ 19 μmol/g·s at 600 °C and ~ 85% as well as ~ 50% of methane selectivity at 450 °C and 600 °C, respectively. The high activity and selectivity of methane can be attributed to the presence of metallic Ni and Ni/NiO/ZnAl2O4 interface under the reaction conditions as evidenced by the XRD results.

Graphic Abstract

High performance Ni–Zn–Al-based oxide/spinel nanostructures is synthesized and NiO/ZnAl2O4 catalyst exhibited higher catalytic activity in the CO2 hydrogenation reaction due to the presence of metal support interaction between Ni and ZnAl2O4 support.
Long-run trend in agricultural yield and climatic factors in Europe
Authors: Agnolucci Paolo , De Lipsis Vincenzo
Published: December 2019

Reliable projections of crop production are an essential tool for the design of feasible policy plans to tackle food security and land allocation, and an accurate characterization of the long-run trend in crop yield is the key ingredient in such projections. We provide several contributions adding to our current understanding of the impact of climatic factors on crop yield. First of all, reflecting the complexity of agricultural systems and the time required for any change to diffuse, we show that crop yield in Europe has historically been characterized by a stochastic trend rather than the deterministic specifications normally used in the literature. Secondly, we found that, contrary to previous studies, the trend in crop yield has slowly changed across time rather than being affected by a single abrupt permanent change. Thirdly, we provide strong evidence that climatic factors have played a major role in shaping the long-run trajectory of crop yield over the decades, by influencing both the size and the statistical nature of the trend. In other words, climatic factors are important not only for the year-to-year fluctuations in crop yield but also for its path in the long-run. Finally, we find that, for most countries in this study, the trend in temperature is responsible for a reduction in the long-run growth rate of yield in wheat, whereas a small gain is produced in maize, except for Southern European countries.
A path-dependent analysis of the effect of location on the development of new universities
Authors: Misra Debananda
Published: December 2019

This article examines the effect of location on the development of new universities. The study was conducted in seven new higher education institutions (HEIs) established in India during 1996–2008. I collected the data by conducting semi-structured interviews with 73 faculty members in the HEIs and from official documents, media reports and opinion pieces about the HEIs. Using the conceptual framework of path dependency, I investigated the tensions and challenges faced by the HEIs in their initial years. I find the placement of the HEIs in their respective locations to be a contingent event that can make the development of HEIs path dependent. I find that the initial conditions and decisions of the HEIs were influenced by the location and led to reactive sequential events in their initial years with effects that were hard to shake off, making their development path dependent. I show that having to develop their infrastructure and constrained by resources, the HEIs started their academic programmes first, followed by their research activities, and outreach and regional engagement.
Vacations Over the Years: A Cross-Lagged Panel Analysis of Tourism Experiences and Subjective Well-Being in the Netherlands
Authors: Mitas Ondrej , Kroesen Maarten
Published: December 2019

Tourism experiences, also called vacations, are known to boost subjective well-being, although it has been argued that the effects are primarily affective in nature and short-lived. We argue that this is a methodological artifact due to the brief duration—1 year or less—of almost all extant longitudinal studies of tourism experience effects. Based on broaden-and-build and personal resource theories, we hypothesize that tourism experiences contribute to both affective and cognitive components of subjective well-being over a multi-year timespan. Using random intercept cross-lagged panel models, we tested these hypotheses in 8 years of panel data based on a representative sample of the population of the Netherlands. We found both between- and within-individual effects of vacation frequency on cognitive as well as affective well-being. More frequent vacationers experienced higher life satisfaction and lower negative affect, while the average participant also experienced slightly higher life satisfaction and positive affect following a year with higher vacation frequency. Increases in life satisfaction also predicted more frequent vacationing in a following year, consistent with an “upward spiral” pattern of improving well-being based on accumulation of positive experiences, as suggested by the broaden-and-build theory.
Magnetic Properties of Structural Steels for Simulation of Crack Monitoring by Finite Element Method
Authors: van der Horst Menno Patrick , Kaminski Miroslaw Lech
Published: December 2019

The metal magnetic memory method is a novel technique for monitoring fatigue cracks in steel structures, which can reduce operational expenses and increase safety by minimizing inspections. The crack geometry can be identified by measuring the self magnetic flux leakage, which is induced by the Earth’s magnetic field and the permanent magnetization. The finite element method can be used to simulate the induced magnetic field around cracks to help interpret the self magnetic flux leakage measurements, but it is unclear what material properties to use. This study aims to determine the magnetic permeability of structural steel for accurate simulation of the induced magnetic field around cracks by the finite element method. The induced magnetic field was extracted from measurements above two square steel plates, one without defect and one with a straight slit, and compared with finite element results in function of the relative permeability. For both plates, a uniform relative permeability could be found for which experimental and numerical results were in good agreement. For the plate without defect and a relative permeability of 350, errors were within 20% and were concentrated around the plate’s edges. For the plate with the slit and a relative permeability of 225, errors were within 5%.
Using Age Structure for a Multi-stage Optimal Control Model with Random Switching Time
Authors: Wrzaczek Stefan , Kuhn Michael , Frankovic Ivan
Published: December 2019

The paper presents a transformation of a multi-stage optimal control model with random switching time to an age-structured optimal control model. Following the mathematical transformation, the advantages of the present approach, as compared to a standard backward approach, are discussed. They relate in particular to a compact and unified representation of the two stages of the model: the applicability of well-known numerical solution methods and the illustration of state and control dynamics. The paper closes with a simple example on a macroeconomic shock, illustrating the workings and advantages of the approach.
Parallel Subjective Well-Being and Choice Experiment Evaluation of Ecosystem Services: Marine and Forest Reserves in Coastal Oregon, USA
Authors: Lindberg Kreg , Swearingen Tommy , White Eric M.
Published: December 2019

There is significant policy and research interest in (a) ecosystem services as a framework for understanding the benefits humans receive from natural systems and (b) subjective well-being as a lens for understanding the effects of public policy decisions. The present study occurred at the intersection of these two fields. Choice experiment and contingent subjective well-being (SWB) models were estimated to understand the potential effects of coastal marine and forest reserves in Oregon, USA. Both models indicated heterogeneity in effects across groups defined by environmental worldview and, for marine reserves, recreation use of reserve areas and employment in the commercial fisheries sector. Methodologically, results suggested that a similar process underlays responses to both types of survey task, with similar model coefficient patterns and frequent consistency in responses. However, differences also were indicated, and differences may be more pronounced in other studies, such as those involving between-subject designs. Contingent SWB is a potentially important measurement approach, but further evaluation is needed, including with respect to the effects of task complexity and evaluation object salience.
The Sensitivity of Estimates of Multiphase Fluid and Solid Properties of Porous Rocks to Image Processing
Authors: Garfi Gaetano , John Cédric M. , Berg Steffen , Krevor Samuel
Published: December 2019

X-ray microcomputed tomography (X-ray μ-CT) is a rapidly advancing technology that has been successfully employed to study flow phenomena in porous media. It offers an alternative approach to core scale experiments for the estimation of traditional petrophysical properties such as porosity and single-phase flow permeability. It can also be used to investigate properties that control multiphase flow such as rock wettability or mineral topology. In most applications, analyses are performed on segmented images obtained employing a specific processing pipeline on the greyscale images. The workflow leading to a segmented image is not straightforward or unique and, for most of the properties of interest, a ground truth is not available. For this reason, it is crucial to understand how image processing choices control properties estimation. In this work, we assess the sensitivity of porosity, permeability, specific surface area, in situ contact angle measurements, fluid–fluid interfacial curvature measurements and mineral composition to processing choices. We compare the results obtained upon the employment of two processing pipelines: non-local means filtering followed by watershed segmentation; segmentation by a manually trained random forest classifier. Single-phase flow permeability, in situ contact angle measurements and mineral-to-pore total surface area are the most sensitive properties, as a result of the sensitivity to processing of the phase boundary identification task. Porosity, interfacial fluid–fluid curvature and specific mineral descriptors are robust to processing. The sensitivity of the property estimates increases with the complexity of its definition and its relationship to boundary shape.
Pixelated Semantic Colorization
Authors: Zhao Jiaojiao , Han Jungong , Shao Ling , Snoek Cees G. M.
Published: December 2019

While many image colorization algorithms have recently shown the capability of producing plausible color versions from gray-scale photographs, they still suffer from limited semantic understanding. To address this shortcoming, we propose to exploit pixelated object semantics to guide image colorization. The rationale is that human beings perceive and distinguish colors based on the semantic categories of objects. Starting from an autoregressive model, we generate image color distributions, from which diverse colored results are sampled. We propose two ways to incorporate object semantics into the colorization model: through a pixelated semantic embedding and a pixelated semantic generator. Specifically, the proposed network includes two branches. One branch learns what the object is, while the other branch learns the object colors. The network jointly optimizes a color embedding loss, a semantic segmentation loss and a color generation loss, in an end-to-end fashion. Experiments on Pascal VOC2012 and COCO-stuff reveal that our network, when trained with semantic segmentation labels, produces more realistic and finer results compared to the colorization state-of-the-art.
Are we together or not? The temporal interplay of monitoring, physiological arousal and physiological synchrony during a collaborative exam
Authors: Malmberg Jonna , Haataja Eetu , Seppänen Tapio , Järvelä Sanna
Published: December 2019

The coordination of cognitive and non-cognitive interactive processes contributes to successful collaboration in groups, but it is hard to evidence in computer-supported collaborative learning (CSCL). Monitoring is a metacognitive process that can be an indicator of a student’s ability to recognize success or failure in collaboration. This study focuses on how monitoring occurs in CSCL during a collaborative exam situation by examining how individual student contributions to monitoring processes are related to physiological synchrony and physiological arousal in groups. The participants were organized in four groups of three members each, and they wore sensors that measured their physiological activity. The data consist of video recordings from collaborative exam sessions lasting 90 minutes and physiological data captured from each student with Empatica 4.0 sensors. The video data were analyzed using qualitative content analysis to identify monitoring events. Students’ physiological arousal was determined through peak detection, and physiological concordance was used as an index for the students’ physiological synchrony. The individual and group level analysis investigated arousal and physiological synchrony in concordance with monitoring during the collaborative exam. The results showed that, in each group, each student contributed to joint monitoring. In addition, the monitoring activities exhibited a significant correlation with the arousal, indicating that monitoring events are reflected in physiological arousal. Physiological synchrony occurred within two groups, which experienced difficulties during the collaborative exam, whereas the two groups who had no physiological synchrony did not experience difficulties. It is concluded that physiological synchrony may be a new indicator for recognizing meaningful events in CSCL
Contact fatigue life prediction of a bevel gear under spectrum loading
Authors: Jia Pan , Liu Huaiju , Zhu Caichao , Wu Wei , Lu Guocheng
Published: December 2019

Rolling contact fatigue (RCF) issues, such as pitting, might occur on bevel gears because load fluctuation induces considerable subsurface stress amplitudes. Such issues can dramatically affect the service life of associated machines. An accurate geometry model of a hypoid gear utilized in the main reducer of a heavy-duty vehicle is developed in this study with the commercial gear design software MASTA. Multiaxial stress—strain states are simulated with the finite element method, and the RCF life is predicted using the Brown–Miller–Morrow fatigue criterion. The patterns of fatigue life on the tooth surface are simulated under various loading levels, and the RCF S–N curve is numerically generated. Moreover, a typical torque—time history on the driven axle is described, followed by the construction of program load spectrum with the rain flow method and the Goodman mean stress equation. The effects of various fatigue damage accumulation rules on fatigue life are compared and discussed in detail. Predicted results reveal that the Miner linear rule provides the most optimistic result among the three selected rules, and the Manson bilinear rule produces the most conservative result.
Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system
Authors: Gatt Ian T. , Allen Tom , Wheat Jon
Published: December 2019

The hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate (< 0.2°) and quasi-static testing (< 6°). Both systems showed a good intraclass coefficient of reliability (ICCs > 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexion–extension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system.
Pore pressure prediction using seismic velocity modeling: case study, Sefid-Zakhor gas field in Southern Iran
Authors: Bahmaei Zahra , Hosseini Erfan
Published: December 2019

Pore pressure estimation is important for both exploration and drilling projects. During the exploration phase, a prediction of pore pressure can be used to evaluate exploration risk factors including the migration of formation fluids and seal integrity. To optimize drilling decisions and well planning in abnormal pressured areas, it is essential to carry out pore pressure predictions before drilling. Mud weight and fracture gradient are essential parameters to have wellbore stability, prevent blowout, lost circulation, kick, sand production and reservoir damages. Predrill pore pressure accurate prediction allows the appropriate mud weight to be selected and allows the casing program to be optimized, thus enabling safety by preventing wellbore collapse and economic drilling by reducing the cost. The goal of this study is to estimate pore pressure relation with subsurface velocity in the Sefid-Zakhor gas field. Manufactured sonic logs are modified using the check shot interval velocity of Sefid-Zakhor well No. 1. The final acoustic impedance model is converted to the velocity model by removing density. Finally, the velocity model is converted to pore pressure using Bowers (in: IADC/SPE drilling conference proceedings, 1995) relation. The results of the pore pressure model are validated by pore pressure data obtained by the MDT well test tool. Generally, the results show the normal trend for pore pressure in the area, except in the left side of the anticline in the 2D seismic section, because of tectonic uplifting.