bluuebunny/crossref_metadata_2025 huggingface dataset:
Attachment, Efficacy Beliefs and Relationship Satisfaction in Dating, Emerging Adult Women
Authors: Julal Cnossen Fay S. , Harman Katherine A. , Butterworth Ruth
Published: August 2019

This study tested the hypothesis that relationship efficacy beliefs mediate the well-documented association between attachment style and relationship satisfaction in a sample of emerging adult women in dating relationships. Further, it explored whether efficacy beliefs vary as a function of romantic experience. Participants (N = 216, Mage = 19.2 years) completed measures of attachment style, efficacy beliefs (mutuality, differentiation, emotional control, and social), and relationship satisfaction. Mutuality beliefs mediated the association between attachment avoidance and anxiety and satisfaction; however, other patterns of mediation were also found. Social, but not relationship, efficacy beliefs differed as a function of number of previous romantic relationships. Results suggest that insecurely attached individuals experience lower relationship satisfaction, in part because they hold less efficacious beliefs about their ability to engage in caregiving and careseeking behaviours. Future longitudinal research might examine how newly forming attachment representations and relationship-relevant efficacy beliefs shape each other.
On the notions of upper and lower density
Authors: Leonetti Paolo , Tringali Salvatore
Published: August 2019

Let $\mathcal {P}(\mathbf{N})$ be the power set of N. We say that a function $\mu ^\ast : \mathcal {P}(\mathbf{N}) \to \mathbf{R}$ is an upper density if, for all X, Y ⊆ N and h, k ∈ N+, the following hold: (f1) $\mu ^\ast (\mathbf{N}) = 1$; (f2) $\mu ^\ast (X) \le \mu ^\ast (Y)$ if X ⊆ Y; (f3) $\mu ^\ast (X \cup Y) \le \mu ^\ast (X) + \mu ^\ast (Y)$; (f4) $\mu ^\ast (k\cdot X) = ({1}/{k}) \mu ^\ast (X)$, where k · X : = {kx: x ∈ X}; and (f5) $\mu ^\ast (X + h) = \mu ^\ast (X)$. We show that the upper asymptotic, upper logarithmic, upper Banach, upper Buck, upper Pólya and upper analytic densities, together with all upper α-densities (with α a real parameter ≥ −1), are upper densities in the sense of our definition. Moreover, we establish the mutual independence of axioms (f1)–(f5), and we investigate various properties of upper densities (and related functions) under the assumption that (f2) is replaced by the weaker condition that $\mu ^\ast (X)\le 1$ for every X ⊆ N. Overall, this allows us to extend and generalize results so far independently derived for some of the classical upper densities mentioned above, thus introducing a certain amount of unification into the theory.
Optical image and microchemical analysis of gold grains from a weathered profile of the Minvoul greenstone belt, northern Gabon
Authors: Iglesias-Martínez Mario , Ordóñez-Casado Berta , Berrezueta Edgar
Published: August 2019

Morphological characterization and quantification of gold particles by optical image analysis (OIA) and by compositional analysis of microprobes using scanning electron microscope and electron microprobe analysis techniques were carried out on gold grains from the Minvoul area (Archean greenstone belt in Gabon). Large grains of almost pure gold were found throughout a weathering profile, which consisted of saprolite, mottled clay zone, iron duricrust, pisolitic gravels and yellow latosol. In the deeper horizons, gold was dissolved as shown by corrosion features on the surface of particles with average sizes of 2.6Φ and 2.35Φ in the saprolite and mottled clay zones, respectively. The occurrence of secondary gold in the duricrust was indicated by the larger size of the nuggets (average, 1.8Φ), the high fineness (> 995 in average) and the close textural relationship between gold and neoformed iron oxyhydroxides. The uppermost horizons composed of yellow latosol and pisolitic gravels were interpreted as transported materials based on their size distribution (average 0.85Φ and 1.34Φ), sorting and shape parameters. The best morphological parameter to describe the whole weathering profile was found to be the perimeter/area ratio. The highest ratios were recorded in the saprolite (average 0.192 μm−1), and decreased towards the surface (average 0.057 μm−1). The combination of the OIA technique and the microchemical analysis of gold grains allowed us to define specific morphological and compositional characteristics of the gold particles for each horizon. Both methods proved to be of great utility to understand gold concentration, dissolution and dispersion processes in supergene environments.
ROBUST FLICKERS OF FREEDOM
Authors: Robinson Michael
Published: September 2019

This essay advances a version of the flicker of freedom defense of the Principle of Alternative Possibilities (PAP) and shows that it is invulnerable to the major objections facing other versions of this defense. Proponents of the flicker defense argue that Frankfurt-style cases fail to undermine PAP because agents in these cases continue to possess alternative possibilities. Critics of the flicker strategy contend that the alternatives that remain open to agents in these cases are unable to rebuff Frankfurt-style attack on the grounds that they are insufficiently robust (that is, morally significant in a way that could ground ascriptions of moral responsibility). Once we see that omissions are capable of constituting robust alternatives, even when they are not intentional, it becomes clear that agents in these cases do indeed possess robust alternative possibilities—alternatives that are ineliminable from cases of this sort. The upshot is that Frankfurt-style cases are theoretically incapable of providing us with good grounds for rejecting PAP.
QUANTILOGRAMS UNDER STRONG DEPENDENCE
Authors: Lee Ji Hyung , Linton Oliver , Whang Yoon-Jae
Published: August 2019

We develop the limit theory of the quantilogram and cross-quantilogram under long memory. We establish the sub-root-n central limit theorems for quantilograms that depend on nuisance parameters. We propose a moving block bootstrap (MBB) procedure for inference and establish its consistency, thereby enabling a consistent confidence interval construction for the quantilograms. The newly developed reduction principles for the quantilograms serve as the main technical devices used to derive the asymptotics and establish the validity of MBB. We report some simulation evidence that our methods work satisfactorily. We apply our method to quantile predictive relations between financial returns and long-memory predictors.
Simultaneous Retrieval of PWV and VTEC by Low‐Cost Multi‐GNSS Single‐Frequency Receivers
Authors: Zhao Chuanbao , Zhang Baocheng , Li Wei , Yuan Yunbin , Li Min
Published: August 2019

Precipitable water vapor (PWV) and ionospheric vertical total electron content (VTEC) are two essential components of space‐atmosphere parameters. The zenith troposphere delay can be converted into PWV, which plays a crucial role in meteorological studies. In the meantime, the importance of the VTEC lies in providing ionospheric corrections for single‐frequency (SF) positioning, navigation, and timing users. Currently, the global navigation satellite system (GNSS) has become one of the most commonly used tools for retrieving PWV and VTEC and normally relies on dual‐frequency, geodetic‐grade receivers and antennas. However, this reliance also implies high hardware costs. In this paper, we propose a single‐frequency ionosphere and troposphere retrieval approach that enables the simultaneous retrieval of PWV and VTEC from multi‐GNSS data collected by low‐cost SF receivers. The use of SF receivers can greatly reduce the cost of hardware. Furthermore, the simultaneous provision of PWV and VTEC also has a positive effect on studying the coupling mechanisms of the ionosphere and troposphere. The accuracy of the estimated zenith troposphere delay can be better than 10 mm compared with the troposphere products published by the International GNSS Service, and the PWV is no more than 3 mm compared with radiosonde‐derived results. Referring to the final International GNSS Service global ionosphere map products and the Jason altimeter data, the VTEC retrieved from the single‐frequency ionosphere and troposphere retrieval method can perform at roughly equal levels compared to the customary dual‐frequency method.
Quantifying Fracture Networks Inferred From Microseismic Point Clouds by a Gaussian Mixture Model With Physical Constraints
Authors: McKean S. H. , Priest J. A. , Dettmer J. , Eaton D. W.
Published: August 2019

Microseismicity is generated by slip on fractures and faults and can be used to infer natural or anthropogenic deformation processes in the subsurface. Yet identifying patterns and fractures from microseismic point clouds is a major challenge that typically relies on the skill and judgment of practitioners. Clustering has previously been applied to tackle this problem, but with limited success. Here, we introduce a probabilistic clustering method to identify fracture networks, based on a Gaussian mixture model algorithm with physical constraints. This method is applied to a rich microseismic data set recorded during the hydraulic fracturing of eight horizontal wells in western Canada. We show that the method is effective for distinguishing hydraulic‐fracture‐created events from induced seismicity. These fractures follow a log‐normal distribution and reflect the physical mechanisms of the hydraulic fracturing process. We conclude that this method has wide applicability for interpreting natural and anthropogenic processes in the subsurface.
Evidence of Magnetic Nulls in the Reconnection at Bow Shock
Authors: Chen Z. Z. , Fu H. S. , Wang Z. , Liu C. M. , Xu Y.
Published: August 2019

Magnetic nulls are believed to play important roles in the energy dissipation during reconnection. Such nulls have been observed in reconnection at the magnetopause, magnetosheath, and magnetotail but have never been observed in reconnection at the bow shock. Recently, four reconnection events were reported at the terrestrial bow shock, by utilizing Magnetospheric Multiscale (MMS) data. We examine whether the magnetic nulls exist in these events. We successfully find radial nulls in three of the events, meaning that spacecraft were close to X points in these events; we, however, cannot find radial nulls in another event, which was actually a crossing of the reconnection exhaust region. The minimum distance between radial nulls and spacecraft is 8 km, about 0.3 ion inertial length. We reconstruct topologies of these nulls and subsequently resolve the reconnection rates in these events. We find that the resolved reconnection rates are comparable with those at the magnetopause and magnetotail. Surprisingly, we do not find electron heating at the radial nulls. Our results are useful to understand the reconnection at bow shock.
Freezing Rain Events Related to Atmospheric Rivers and Associated Mechanisms for Western North America
Authors: Liang J. , Sushama L.
Published: September 2019

Atmospheric rivers (ARs) are responsible for hazardous hydrometeorological events over western North America. For the period 2070–2099 relative to 1976–2005, regional climate model simulations driven by two coupled global climate models for the RCP4.5 and 8.5 scenarios project up to 90% increase in AR occurrences over western North America. Results also suggest that the increase in AR‐related freezing rain (FR) events is possibly due to changes in both dynamical and thermal mechanisms associated with AR events. In the west coast of Canada, AR‐related FR events are projected to intensify, which is facilitated by the increased midlevel ascent related to differential vorticity advection associated with ARs. The fraction of AR‐related FR amount is projected to increase over the inland of western U.S. and the west coast of Canada, which is possibly driven by the increased temperature difference between the subfreezing near‐surface layer and the above‐freezing layer aloft.
Characterization of Extreme Wet‐Bulb Temperature Events in Southern Pakistan
Authors: Monteiro Joy Merwin , Caballero Rodrigo
Published: September 2019

We study extreme wet‐bulb temperature (Tw) events in a regional hot spot of high Tw values in southwest Pakistan's Indus Valley. We focus on the May–June premonsoon months and employ a combination of station data, ERA‐Interim reanalysis, and trajectory calculations to analyze the extreme events. We find that the events are associated with anomalous influx of marine air from the Arabian Sea. The air flows in a shallow layer below 950 hPa and is heated and moistened by diabatic processes over land, arriving at the hot spot region with very high Tw. We surmise that surface evaporation within the strip of well‐irrigated land flanking the Indus River plays a major role in generating these extreme Tw values. Our results imply that studies of extreme Tw events in future, warmer climates must pay close attention to fine‐scale diabatic processes within the boundary layer, especially evaporation over land.
Electrically Anisotropic Crust From Three‐Dimensional Magnetotelluric Modeling in the Western Junggar, NW China
Authors: Liu Ying , Junge Andreas , Yang Bo , Löwer Alexander , Cembrowski Marcel , Xu Yixian
Published: August 2019

An island arc environment related to intraoceanic subduction or ridge subduction from the Late Carboniferous to the Early Permian has been proposed for the formation of Western Junggar, NW China, situated in the southwest of Central Asian Orogenic Belt. However, the details and consequences of the subduction remain controversial. To further identify the relics of the Late Carboniferous subduction at depth, three magnetotelluric profiles were deployed. Phase tensors, real induction arrows, and three‐dimensional (3‐D) isotropic resistivity models indicate the presence of a 3‐D anisotropic resistivity structure in the crust. Consequently, a 3‐D anisotropic resistivity model was constructed by forward modeling. The 3‐D anisotropic resistivity model contains two azimuthally anisotropic middle‐upper crust anomalies with minimum resistivity striking N90°E at depths of 5 to 20 km, and an azimuthally anisotropic lower crust anomaly with minimum resistivity striking N20°E at depths of 20 to 46 km. The electrically anisotropic anomalies are closely related to relatively high shear‐wave velocities with significant negative radial anisotropy. The anisotropies in the middle‐to‐upper crust and the lower crust are related to the oceanic ridge (N90°E) subduction with a slab window in the Late Carboniferous and the remnant oceanic slab, respectively. The magnetotelluric observations support a NW70° subduction with an intraoceanic ridge‐transform system in the Late Carboniferous and a remnant oceanic slab trapped in Western Junggar.
Eddies in the Western Arctic Ocean From Spaceborne SAR Observations Over Open Ocean and Marginal Ice Zones
Authors: Kozlov Igor E. , Artamonova Anastasia V. , Manucharyan Georgy E. , Kubryakov Arseny A.
Published: August 2019

The Western Arctic Ocean is a host to major ocean circulation systems, many of which generate eddies that can transport water masses and corresponding tracers over long distances from their formation sites. However, comprehensive observations of critical eddy characteristics are currently not available and are limited to spatially and temporally sparse in situ observations. Here we use high‐resolution spaceborne synthetic aperture radar measurements to detect eddies from their surface imprints in ice‐free sea surface roughness, and in sea ice patterns throughout marginal ice zones. We provide the first estimate of eddy characteristics extending over the seasonally ice‐free and marginal ice zone regions of the Western Arctic Ocean, including their locations, diameters, and monthly distribution. Using available synthetic aperture radar data, we identified over 4,000 open ocean eddies, as well as over 3,500 eddies in marginal ice zones from June to October in 2007, 2011, and 2016. Eddies range in size between 0.5 and 100 km and are frequently found over the shelf and near continental slopes but also present in the deep Canada Basin and over the Chukchi Plateau. We find that cyclonic eddies are twice more frequent compared to anticyclonic eddies at the surface, distinct from the dominating anticyclonic eddies observed at depth by in situ moorings and ice‐tethered profilers. Our study supports the notion that eddies are ubiquitous in the Western Arctic Ocean even in the presence of sea ice and emphasizes the need for improved ocean observations and modeling at eddy scales.
Local Regions Associated With Interdecadal Global Temperature Variability in the Last Millennium Reanalysis and CMIP5 Models
Authors: Parsons L.A. , Hakim G.J.
Published: August 2019

Despite the importance of interdecadal climate variability, we have a limited understanding of which geographic regions are associated with global temperature variability at these timescales. The instrumental record tends to be too short to develop sample statistics to study interdecadal climate variability, and Coupled Model Intercomparison Project, Phase 5 (CMIP5) climate models tend to disagree about which locations most strongly influence global mean interdecadal temperature variability. Here we use a new paleoclimate data assimilation product, the Last Millennium Reanalysis (LMR), to examine where local variability is associated with global mean temperature variability at interdecadal timescales. The LMR framework uses an ensemble Kalman filter data assimilation approach to combine the latest paleoclimate data and state‐of‐the‐art model data to generate annually resolved field reconstructions of surface temperature, which allow us to explore the timing and dynamics of preinstrumental climate variability in new ways. The LMR consistently shows that the middle‐ to high‐latitude north Pacific and the high‐latitude North Atlantic tend to lead global temperature variability on interdecadal timescales. These findings have important implications for understanding the dynamics of low‐frequency climate variability in the preindustrial era.
Simple and Applicable Method for Estimating Evapotranspiration and Its Components in Arid Regions
Authors: Xiong Yu Jiu , Zhao Wen Li , Wang Pei , Paw U Kyaw Tha , Qiu Guo Yu
Published: August 2019

Land evapotranspiration (ET), which involves the exchange of energy and water between the atmosphere and land, is dynamic and affects the spatiotemporal distribution of water resources, a key limiting factor in arid regions. The accurate quantification of ET and its two components, that is, soil evaporation (Es) and vegetation transpiration (Ev), is crucial for managing water resources to ensure sustainable development. However, estimating ET and its components is challenging due to limitations associated with the structure and parameterization of models. The three‐temperature (3T) model, which includes limited inputs that are key to the ET process (e.g., net radiation and temperature), is hypothesized to be robust. In conjunction with the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) project, this study was performed in a heterogeneous oasis in northwestern China using relatively high‐density eddy covariance observations. The mean absolute percent error values of the ET and its components estimated with the 3T model from the field scale (flux observations as model inputs) to large scales (Fluke, Advanced Spaceborne Thermal Emission and Reflection Radiometer [ASTER] and Moderate Resolution Imaging Spectroradiometer [MODIS] data as model inputs) range from 9 to 25% over different landscapes. The ET estimates from the simple 3T model contained less bias than those from the Penman‐Monteith equation, which requires more model inputs and parameterization. When the components were separated in the 3T model based on high‐resolution images, such as Fluke and ASTER, the Ev/ET values were comparable to the isotope‐based observations, and the mean absolute percent error values were <10%. With its limited inputs, the 3T model is able to simply and easily estimate ET and its components.
Organic Aerosol Processing During Winter Severe Haze Episodes in Beijing
Authors: Zhao Jian , Qiu Yanmei , Zhou Wei , Xu Weiqi , Wang Junfeng , Zhang Yingjie , Li Linjie , Xie Conghui , Wang Qingqing , Du Wei , Worsnop Douglas R. , Canagaratna Manjula R. , Zhou Libo , Ge Xinlei , Fu Pingqing , Li Jie , Wang Zifa , Donahue Neil M. , Sun Yele
Published: August 2019

Organic aerosol (OA) constituted a large fraction of aerosol particles during severe haze episodes in winter in northern China, yet our understanding of its physical and chemical processing was limited. Here we investigate the sources and processes of OA during four haze episodes in winter in 2016 using high‐resolution aerosol mass spectrometer. The PM2.5 reached 400 μg/m3 during the severest episode (Ep1) when Beijing issued a red alert and implemented strict emission controls. Our results showed that secondary OA (SOA) dominated OA during haze episodes on average accounting for 46–66% of OA and was comparable to secondary inorganic aerosol (SIA) with the SOA/SIA ratios being 0.51–0.72. Primary OA from fossil‐fuel combustion, biomass burning, and cooking presented very strong diurnal variations during haze episodes and contributed up to 60% in OA at night. Comparatively, the changes in semivolatile and low‐volatility SOA were relatively small except a substantial increase in aqueous phase‐related oxidized OA (aq‐OOA) during Ep1 with high relative humidity and aerosol water content. aq‐OOA fell well into a small region in the middle of the triangle plot of f44 versus f43 (fraction of m/z 44 and 43 in OA, respectively), which can be used as a diagnostic for the presence of aqueous phase processing of SOA. In addition, the increases of SO2+/SO3+ as a function of relative humidity, the triangle plot of
versus
, and high nitrogen‐to‐carbon ratio in aq‐OOA suggest the potential formation of sulfur‐ and nitrogen‐containing organic compounds through aqueous phase processing.
Reventilation Episodes During the Sapropel S1 Deposition in the Eastern Mediterranean Based on Holococcolith Preservation
Authors: Incarbona Alessandro , Abu‐Zied Ramadan H. , Rohling Eelco J. , Ziveri Patrizia
Published: September 2019

Organic‐rich layers (sapropels), preserved in eastern Mediterranean marine sediment records, represent pronounced perturbations to thermohaline circulation and environmental conditions in the basin, in response to enhanced African monsoon activity and subsequent massive freshwater discharge. During the most recent event, Sapropel S1 formed between 10.8 and 6.1 ka, when freshwater‐driven stratification caused seafloor anoxia below ~1,800‐m depth, as a result of both failure of deep water formation and enhanced productivity. Here we analyze coccolith assemblages from the open eastern Mediterranean that form a west‐east transect across the basin and provide insights on past environmental changes. We focus on holococcoliths, which are specifically produced by coccolithophores as part of their life cycle during the haploid phase. Since holococcolith calcification is characterized by nanocrystals highly susceptible to dissolution, we are testing their potential preservation under different bottom environmental conditions, including the effect of postdepositional oxidation. A comparison with benthic foraminifera assemblages in a core recovered close to Lybia reveals that holococcolith preservation is enhanced during seafloor reventilation and benthic foraminiferal repopulation in the middle to upper part of the record, before the actual sapropel termination. There are two such events of improved deep‐water oxygenation in the Aegean and Adriatic Seas at 8.2 and 7.4 ka. The latter episode marks the onset of the transition to restored circulation in the eastern Mediterranean Sea, due to resumption of deep‐water formation in the southern Aegean Sea and the conclusion of enhanced biogenic productivity.
Cumulative and Coseismic (During the 2016 Mw6.6 Aketao Earthquake) Deformation of the Dextral‐Slip Muji Fault, Northeastern Pamir Orogen
Authors: Li Tao , Schoenbohm Lindsay M. , Chen Jie , Yuan Zhaode , Feng Wanpeng , Li Wenqiao , Xu Jianhong , Owen Lewis A. , Sobel Edward R. , Zhang Boxuan , Zheng Wenjun , Zhang Peizhen
Published: August 2019

Located at the northwestern syntaxis of the India‐Asia convergence zone, the Pamir orogen is characterized by complicated and strong active deformation. Constraining the detailed geometry and kinematics of major active structures is important both for understanding modern tectonic processes and for evaluating potential seismic hazards of the region. Our work focuses on the Muji Fault in the northeastern Pamir. Based on cumulative deformation recorded by landforms and coseismic deformation during the 2016 Mw6.6 Aketao earthquake, we determine the spatial extent, slip motion, fault‐plane geometry, and slip rate of the fault, on the basis of which we clarify its role in the modern tectonics of the Pamir and investigate its seismic behavior and associated seismic hazards. Our study indicates that (i) the Muji Fault, along with the Kongur Extensional System to its south, acts as a boundary fault that accommodates a relative divergence rate of 1.4–2.0°/Ma between the central‐western and eastern Pamir; (ii) geometric discontinuities along the fault exerted an important control on seismic rupture termination and slip gap formation during the Aketao earthquake; and (iii) the cumulative surface‐faulting deformation cannot be formed coseismically by repetitions of the Aketao earthquake, implying significant aseismic (postseismic and/or interseismic) creeping or possibly larger (approximately Mw7.2), surface‐faulting earthquakes. Our study highlights the usefulness of correlating cumulative and coseismic deformation patterns in active tectonic investigations and regional seismic hazard evaluations.
Predicting superhard materials via a machine learning informed evolutionary structure search
Authors: Avery Patrick , Wang Xiaoyu , Oses Corey , Gossett Eric , Proserpio Davide M. , Toher Cormac , Curtarolo Stefano , Zurek Eva
Published: September 2019

The computational prediction of superhard materials would enable the in silico design of compounds that could be used in a wide variety of technological applications. Herein, good agreement was found between experimental Vickers hardnesses, Hv, of a wide range of materials and those calculated by three macroscopic hardness models that employ the shear and/or bulk moduli obtained from: (i) first principles via AFLOW-AEL (AFLOW Automatic Elastic Library), and (ii) a machine learning (ML) model trained on materials within the AFLOW repository. Because $$H_{\mathrm{v}}^{{\mathrm{ML}}}$$

H

v

ML

values can be quickly estimated, they can be used in conjunction with an evolutionary search to predict stable, superhard materials. This methodology is implemented in the XtalOpt evolutionary algorithm. Each crystal is minimized to the nearest local minimum, and its Vickers hardness is computed via a linear relationship with the shear modulus discovered by Teter. Both the energy/enthalpy and $$H_{{\mathrm{v,Teter}}}^{{\mathrm{ML}}}$$

H

v,Teter

ML

are employed to determine a structure’s fitness. This implementation is applied towards the carbon system, and 43 new superhard phases are found. A topological analysis reveals that phases estimated to be slightly harder than diamond contain a substantial fraction of diamond and/or lonsdaleite.
Health worker and patient views on implementation of smoking cessation in routine tuberculosis care
Authors: Boeckmann Melanie , Warsi Sahil , Noor Maryam , Dogar Omara , Mustagfira Esha Haowa , Firoze Fariza , Zahid Raana , Readshaw Anne , Siddiqi Kamran , Kotz Daniel ,   the TB & Tobacco Consortium, Keding Ada , Gabe Rhian , Marshall Anna , Parrott Steve , Swami Shilpi , Khan Amina , Raja Sonia , Sohail Salman , Huque Rumana , Barua Deepa , Huque Samina , Jahan Iashrat , Fatima Razia , Qadeer Ejaz , Sheikh Aziz , Elsey Helen , Karki Jiban , Králíková Eva , Nohavova Iveta , Zvolska Kamila , Pankova Alexandra , Baral Sushil , Regmi Shophika , Shrestha Prabin , Khanal Sudeepa , Joshi Basant
Published: September 2019

Smoking worsens tuberculosis (TB) outcomes. Persons with TB who smoke can benefit from smoking cessation. We report findings of a multi-country qualitative process evaluation assessing barriers and facilitators to implementation of smoking cessation behaviour support in TB clinics in Bangladesh and Pakistan. We conducted semi-structured qualitative interviews at five case study clinics with 35 patients and 8 health workers over a period of 11 months (2017–2018) at different time points during the intervention implementation phase. Interviews were conducted by trained researchers in the native languages, audio-recorded, transcribed into English and analysed using a combined deductive–inductive approach guided by the Consolidated Framework for Implementation Research and Theoretical Domains Framework. All patients report willingness to quit smoking and recent quit attempts. Individuals’ main motivations to quit are their health and the need to financially provide for a family. Behavioural regulation such as avoiding exposure to cigarettes and social influences from friends, family and colleagues are main themes of the interviews. Most male patients do not feel shy admitting to smoking, for the sole female patient interviewee stigma was an issue. Health workers report structural characteristics such as high workload and limited time per patient as primary barriers to offering behavioural support. Self-efficacy to discuss tobacco use with women varies by health worker. Systemic barriers to implementation such as staff workload and socio-cultural barriers to cessation like gender relations, stigma or social influences should be dealt with creatively to optimize the behaviour support for sustainability and scale-up.
Data-driven unsupervised clustering of online learner behaviour
Authors: Peach Robert L. , Yaliraki Sophia N. , Lefevre David , Barahona Mauricio
Published: September 2019

The widespread adoption of online courses opens opportunities for analysing learner behaviour and optimising web-based learning adapted to observed usage. Here, we introduce a mathematical framework for the analysis of time-series of online learner engagement, which allows the identification of clusters of learners with similar online temporal behaviour directly from the raw data without prescribing a priori subjective reference behaviours. The method uses a dynamic time warping kernel to create a pair-wise similarity between time-series of learner actions, and combines it with an unsupervised multiscale graph clustering algorithm to identify groups of learners with similar temporal behaviour. To showcase our approach, we analyse task completion data from a cohort of learners taking an online post-graduate degree at Imperial Business School. Our analysis reveals clusters of learners with statistically distinct patterns of engagement, from distributed to massed learning, with different levels of regularity, adherence to pre-planned course structure and task completion. The approach also reveals outlier learners with highly sporadic behaviour. A posteriori comparison against student performance shows that, whereas high-performing learners are spread across clusters with diverse temporal engagement, low performers are located significantly in the massed learning cluster, and our unsupervised clustering identifies low performers more accurately than common machine learning classification methods trained on temporal statistics of the data. Finally, we test the applicability of the method by analysing two additional data sets: a different cohort of the same course, and time-series of different format from another university.
Fast Groupwise Registration Using Multi-Level and Multi-Resolution Graph Shrinkage
Authors: Dong Pei , Cao Xiaohuan , Yap Pew-Thian , Shen Dinggang
Published: September 2019

Groupwise registration aligns a set of images to a common space. It can however be inefficient and ineffective when dealing with datasets with significant anatomical variations. To mitigate these problems, we propose a groupwise registration framework based on hierarchical multi-level and multi-resolution shrinkage of a graph set. First, to deal with datasets with complex inhomogeneous image distributions, we divide the images hierarchically into multiple clusters. Since the images in each cluster have similar appearances, they can be registered effectively. Second, we employ a multi-resolution strategy to reduce computational cost. Experimental results on two public datasets show that our proposed method yields state-of-the-art registration accuracy with significantly reduced computational time.
Success of Montreal Protocol Demonstrated by Comparing High-Quality UV Measurements with “World Avoided” Calculations from Two Chemistry-Climate Models
Authors: McKenzie Richard , Bernhard Germar , Liley Ben , Disterhoft Patrick , Rhodes Steve , Bais Alkiviadis , Morgenstern Olaf , Newman Paul , Oman Luke , Brogniez Colette , Simic Stana
Published: September 2019

The Montreal Protocol on Substances that Deplete the Ozone Layer has been hailed as the most successful environmental treaty ever (https://www.unenvironment.org/news-and-stories/story/montreal-protocol-triumph-treaty). Yet, although our main concern about ozone depletion is the subsequent increase in harmful solar UV radiation at the Earth’s surface, no studies to date have demonstrated its effectiveness in that regard. Here we use long-term UV Index (UVI) data derived from high-quality UV spectroradiometer measurements to demonstrate its success in curbing increases in UV radiation. Without this landmark agreement, UVI values would have increased at mid-latitude locations by approximately 20% between the early 1990s and today and would approximately quadruple at mid-latitudes by 2100. In contrast, an analysis of UVI data from multiple clean-air sites shows that maximum daily UVI values have remained essentially constant over the last ~20 years in all seasons, and may even have decreased slightly in the southern hemisphere, especially in Antarctica, where effects of ozone depletion were larger. Reconstructions of the UVI from total ozone data show evidence of increasing UVI levels in the 1980s, but unfortunately, there are no high-quality UV measurements available prior to the early 1990s to confirm these increases with direct observations.
Model of Anisotropic Reverse Cardiac Growth in Mechanical Dyssynchrony
Authors: Arumugam Jayavel , Mojumder Joy , Kassab Ghassan , Lee Lik Chuan
Published: September 2019

Based on recent single-cell experiments showing that longitudinal myocyte stretch produces both parallel and serial addition of sarcomeres, we developed an anisotropic growth constitutive model with elastic myofiber stretch as the growth stimuli to simulate long-term changes in biventricular geometry associated with alterations in cardiac electromechanics. The constitutive model is developed based on the volumetric growth framework. In the model, local growth evolutions of the myocyte’s longitudinal and transverse directions are driven by the deviations of maximum elastic myofiber stretch over a cardiac cycle from its corresponding local homeostatic set point, but with different sensitivities. Local homeostatic set point is determined from a simulation with normal activation pattern. The growth constitutive model is coupled to an electromechanics model and calibrated based on both global and local ventricular geometrical changes associated with chronic left ventricular free wall pacing found in previous animal experiments. We show that the coupled electromechanics-growth model can quantitatively reproduce the following: (1) Thinning and thickening of the ventricular wall respectively at early and late activated regions and (2) Global left ventricular dilation as measured in experiments. These findings reinforce the role of elastic myofiber stretch as a growth stimulant at both cellular level and tissue-level.
The influence of inter-particle forces on diffusion at the nanoscale
Authors: Giorgi Francesco , Coglitore Diego , Curran Judith M. , Gilliland Douglas , Macko Peter , Whelan Maurice , Worth Andrew , Patterson Eann A.
Published: September 2019

Van der Waals and electrostatic interactions are the dominant forces acting at the nanoscale and they have been reported to directly influence a range of phenomena including surface adhesion, friction, and colloid stability but their contribution on nanoparticle diffusion dynamics is still not clear. In this study we evaluated experimentally the changes in the diffusion coefficient of nanoparticles as a result of varying the magnitude of Van der Waals and electrostatic forces. We controlled the magnitude of these forces by varying the ionic strength of a salt solution, which has been shown to be a parameter that directly controls the forces, and found by tracking single nanoparticles dispersed in solutions with different salt molarity that the diffusion of nanoparticles increases with the magnitude of the electrostatic forces and Van der Waals forces. Our results demonstrate that these two concurrently dynamic forces play a pivotal role in driving the diffusion process and must be taken into account when considering nanoparticle behaviour.
Transcriptomic and functional analyses of 3D placental extravillous trophoblast spheroids
Authors: Wong Michael K. , Wahed Mishquatul , Shawky Sarah A. , Dvorkin-Gheva Anna , Raha Sandeep
Published: August 2019

Placental extravillous trophoblast (EVT) invasion is essential in establishing proper blood supply to the fetus during pregnancy. However, traditional 2D in vitro systems do not model the in vivo invasion process in an anatomically-relevant manner. Our objectives were to develop a 3D spheroid model that would allow better emulation of placental invasion in vitro and to characterize the transcriptomic and functional outcomes. HTR8/SVneo EVT cells were self-assembled into 3D spheroids using ultra-low attachment plates. Transcriptomic profiling followed by gene set enrichment and gene ontology analyses revealed major global transcriptomic differences, with significant up-regulations in EVTs cultured as 3D spheroids in canonical pathways and biological processes such as immune response, angiogenesis, response to stimulus, wound healing, and others. These findings were further validated by RT-qPCR, showing significant up-regulations in genes and/or proteins related to epithelial-mesenchymal transition, cell-cell contact, angiogenesis, and invasion/migration. A high-throughput, spheroid invasion assay was applied to reveal the dynamic invasion of EVTs away from the spheroid core into extracellular matrix. Lastly, lipopolysaccharide, dexamethasone, or Δ9-tetrahydrocannabinol exposure was found to impact the invasion of EVT spheroids. Altogether, we present a well-characterized, 3D spheroid model of EVT invasion and demonstrate its potential use in drug and toxin screening during pregnancy.
M1-like macrophage polarization prevails in young children with classic Hodgkin Lymphoma from Argentina
Authors: Jimenez O. , Barros M. H. , De Matteo E. , Garcia Lombardi M. , Preciado M. V. , Niedobitek G. , Chabay P.
Published: September 2019

The microenvironment in classical Hodgkin lymphoma (cHL) comprises a mixture of different types of cells, which are responsible for lymphoma pathogenesis and progression. Even though microenvironment composition in adult cHL has been largely studied, only few groups studied pediatric cHL, in which both Epstein Barr virus (EBV) infection and age may display a role in their pathogenesis. Furthermore, our group described that EBV is significantly associated with cHL in Argentina in patients under the age of 10 years old. For that reason, our aim was to describe the microenvironment composition in 46 pediatric cHL patients. M1-like polarization status prevailed in the whole series independently of EBV association. On the other hand, in children older than 10 years, a tolerogenic environment illustrated by higher FOXP3 expression was proved, accompanied by a macrophage polarization status towards M2. In contrast, in children younger than 10 years, M1-like was prevalent, along with an increase in cytotoxic GrB+ cells. This study supports the notion that pediatric cHL exhibits a particular tumor microenvironment composition.
Cell grazing and Haemonchus contortus control in sheep: lessons from a two-year study in temperate Western Europe
Authors: Ruiz-Huidobro C. , Sagot L. , Lugagne S. , Huang Y. , Milhes M. , Bordes L. , Prévot F. , Grisez C. , Gautier D. , Valadier C. , Sautier M. , Jacquiet P.
Published: September 2019

Managing infections of sheep with anthelmintic resistant gastrointestinal nematodes (GIN) is a major challenge for sheep producers in Western Europe. New methods of grazing management have been poorly explored as a component of an integrated and sustainable control of these parasites. Therefore, the purpose of this study was to evaluate the effect of two different types of grazing systems of sheep (intensive cell grazing versus conventional rotational grazing) on GIN infections over two years in a farm located in a temperate environment of Western France. When considering the whole study, the type of grazing system did not influence significantly the intensity of egg excretions of adult ewes even if the proportion of ewes excreting high numbers of GIN eggs was higher in cell grazing system than in rotational grazing system. The most striking result of this survey was the effect of grazing system on the GIN species composition harbored by ewes and by their lambs: with time, the proportions of H. contortus infections were lower in cell grazing system than in rotational grazing system. In conclusion, the cell grazing system, as implemented in this study, could limit the importance of this highly pathogenic nematode species in sheep.
Safety and neurochemical profiles of acute and sub-chronic oral treatment with agmatine sulfate
Authors: Bergin David H. , Jing Yu , Williams Gail , Mockett Bruce G. , Zhang Hu , Abraham Wickliffe C. , Liu Ping
Published: September 2019

Agmatine (decarboxylated arginine) exerts numerous central nervous system (CNS) dependent pharmacological effects and may potentially modulate altered neurochemistry seen in neurological disorders. In preclinical studies, injection has been the predominant route of systemic administration. However, a significant translational step would be the use of oral agmatine treatment at therapeutic doses and better understanding of L-arginine metabolic profiles in the CNS post-treatment. The present study systematically investigated the tolerability, safety and brain-plasma neurochemistry following daily oral agmatine sulfate treatment (via gavage) to wild-type (WT) mice up to 900 mg/kg for one week (Experiment 1) or WT and APPswe/PS1ΔE9 transgenic (Tg) mice at 300 mg/kg for fifteen weeks (Experiment 2). Agmatine treatment in both experiments was well tolerated with no marked behavioural impairments, and gross necropsy and organ histology revealed no pathological alterations after 15-week dosing. Moreover, oral treatment increased agmatine levels in the hippocampus and plasma of WT mice (Experiment 1), and in 6 brain regions examined (but not plasma) of WT and Tg mice (Experiment 2), at 30 minutes or 24 hours post-treatment respectively. This study provides fundamental pre-clinical evidence that daily oral delivery of agmatine sulfate to both WT and Tg mice is safe and well tolerated. Exogenous agmatine passes through the blood brain barrier and accumulates in the brain to a greater extent in Tg mice. Furthermore exogenous agmatine has differential actions in the brain and periphery, and its effect on brain putrescine appears to be dependent on the time post-treatment.
Efficient generation of Knock-in/Knock-out marmoset embryo via CRISPR/Cas9 gene editing
Authors: Kumita Wakako , Sato Kenya , Suzuki Yasuhiro , Kurotaki Yoko , Harada Takeshi , Zhou Yang , Kishi Noriyuki , Sato Kengo , Aiba Atsu , Sakakibara Yasubumi , Feng Guoping , Okano Hideyuki , Sasaki Erika
Published: September 2019

Genetically modified nonhuman primates (NHP) are useful models for biomedical research. Gene editing technologies have enabled production of target-gene knock-out (KO) NHP models. Target-gene-KO/knock-in (KI) efficiency of CRISPR/Cas9 has not been extensively investigated in marmosets. In this study, optimum conditions for target gene modification efficacies of CRISPR/mRNA and CRISPR/nuclease in marmoset embryos were examined. CRISPR/nuclease was more effective than CRISPR/mRNA in avoiding mosaic genetic alteration. Furthermore, optimal conditions to generate KI marmoset embryos were investigated using CRISPR/Cas9 and 2 different lengths (36 nt and 100 nt) each of a sense or anti-sense single-strand oligonucleotide (ssODN). KIs were observed when CRISPR/nuclease and 36 nt sense or anti-sense ssODNs were injected into embryos. All embryos exhibited mosaic mutations with KI and KO, or imprecise KI, of c-kit. Although further improvement of KI strategies is required, these results indicated that CRISPR/Cas9 may be utilized to produce KO/KI marmosets via gene editing.
Migrating eastern North Pacific gray whale call and blow rates estimated from acoustic recordings, infrared camera video, and visual sightings
Authors: Guazzo Regina A. , Weller David W. , Europe Hollis M. , Durban John W. , D’Spain Gerald L. , Hildebrand John A.
Published: August 2019

During the eastern North Pacific gray whale 2014–2015 southbound migration, acoustic call recordings, infrared blow detections, and visual sightings were combined to estimate cue rates, needed to convert detections into abundance. The gray whale acoustic call rate ranged from 2.3–24 calls/whale/day during the peak of the southbound migration with an average of 7.5 calls/whale/day over both the southbound and northbound migrations. The average daily calling rate increased between 30 December–13 February. With a call rate model, we estimated that 4,340 gray whales migrated south before visual observations began on 30 December, which is 2,829 more gray whales than used in the visual estimate, and would add approximately 10% to the abundance estimate. We suggest that visual observers increase their survey effort to all of December to document gray whale presence. The infrared camera blow rate averaged 49 blows/whale/hour over 5–8 January. Probability of detection of a whale blow by the infrared camera was the same at night as during the day. However, probability of detection decreased beyond 2.1 km offshore, whereas visual sightings revealed consistent whale densities up to 3 km offshore. We suggest that future infrared camera surveys use multiple cameras optimised for different ranges offshore.