bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimizing Island Refuges against global Catastrophic and Existential Biological Threats: Priorities and Preparations
Authors: Boyd Matt , Wilson Nick 
Published: April 2021

AbstractHuman civilization is vulnerable to global catastrophic biological threats and existential threats. Policy to mitigate the impact of major biological threats should consider worst‐case scenarios. We aimed to strengthen existing research on island refuges as a mitigating mechanism against such threats by considering five additional factors as well as recent literature on catastrophic risks and resilience. We also analyzed the performance of potential refuge islands during early phases the COVID‐19 pandemic. Using a composite indicator (scored from 0–1) based on 14 global macroindices, we present analysis supporting Australia (0.71), New Zealand (0.64), and Iceland (0.58) as the leading candidate island nation refuges to safeguard the survival of humanity and a flourishing technological civilization from the threat of a catastrophic pandemic. Data from the COVID‐19 pandemic supports this finding where islands have performed relatively well. We discuss the persisting weaknesses of even the best candidate refuges and the growing literature describing what preparations such a refuge should ensure to enhance resilience. Refuge preparations by Australia and New Zealand, in particular, may additionally provide some immunity against winter‐inducing catastrophes such as global nuclear war. Existing disaster resilience frameworks such as the Sendai framework could be worded to mandate preventive measures against global catastrophic and existential threats. The issue of island refuges against certain global catastrophic risks should be raised at relevant international political summits.
An n‐dimensional Rosenbrock distribution for Markov chain Monte Carlo testing
Authors: Pagani Filippo , Wiegand Martin , Nadarajah Saralees 
Published: April 2021

AbstractThe Rosenbrock function is a ubiquitous benchmark problem in numerical optimization, and variants have been proposed to test the performance of Markov chain Monte Carlo algorithms on distributions with a curved and narrow shape. In this work we discuss the Rosenbrock distribution and the advantages and limitations of its current n‐dimensional extensions. We then propose a new extension to arbitrary dimensions called the Hybrid Rosenbrock distribution, which addresses all the limitations that affect the current extensions. The Hybrid Rosenbrock distribution is composed of conditional normal kernels arranged in such a way that preserves the key features of the original Rosenbrock kernel. Moreover, due to its structure, the Hybrid Rosenbrock distribution is analytically tractable, and possesses several desirable properties which make it an excellent test model for computational algorithms. We conclude with numerical experiments that show how commonly used Markov chain Monte Carlo algorithms may fail to explore densities with curved correlation structure, restating the importance of a reliable benchmark problem for this class of densities.
Exit from open‐ended social benefits into employment: Access to work, active labour market policies and work intensity
Authors: Mato‐Díaz Fco Javier , Miyar‐Busto María 
Published: April 2021

AbstractAn analysis is made of the sensitivity of minimum income schemes to the effects of labour market participation and active labour market services. Data comes from the only regional scheme in Spain that has an open‐ended duration and has existed for a period long enough to be analysed. This scheme shows the closest resemblance with the first national minimum income programme, introduced by the Spanish government in 2020 (Ingreso Mínimo Vital). Survival analysis results show that people who access full‐time work contracts have a higher probability of exiting into employment than those who do not, although the majority of people who sign at least one contract remain in the scheme, nevertheless. A defining element for exiting the scheme is work intensity. Thus, despite the fact that the scheme is compatible with some jobs, results suggest that increasing the compatibility between work and benefit would be a crucial factor in facilitating exit from the scheme. In addition, analyses of the elements defining the probability of signing a work contract while on the benefit show that active labour market policies heighten said probability, but do not subsequently influence exit from the scheme.
Genomic andin vitropharmacodynamic analysis of rifampicin resistance in multidrug‐resistant canineStaphylococcus pseudintermediusisolates
Authors: Hicks Karly , Tan Yongjun , Cao Wenqi , Hathcock Terri , Boothe Dawn , Kennis Robert , Zhang Dapeng , Wang Xu , White Amelia 
Published: April 2021

BackgroundAntimicrobial resistance is a growing concern in canineStaphylococcus pseudintermediusdermatitis. Treatment with rifampicin (RFP) is considered only in meticillin‐resistant and multidrug‐resistantS. pseudintermedius(MDR‐MRSP).Hypothesis/ObjectivesTo determine an optimal RFP dosing for MDR‐MRSP treatment without induction of RFP resistance and identify causal mutations for antimicrobial resistance.Methods and materialsTime–kill assays were performed in a control isolate and three MDR‐MRSP isolates at six clinically relevant concentrations [32 to 1,024 × MIC (the minimum inhibitory concentration)]. Whole‐genome resequencing and bioinformatic analysis were performed in the resistant strains developed in this assay.ResultsThe genomic analysis identified nine antimicrobial resistance genes (ARGs) in MDR‐MRSP isolates, which are responsible for resistance to seven classes of antibiotics. RFP activity against all four isolates was consistent with a time‐dependent and bacteriostatic response. RFP resistance was observed in six of the 28 time–kill assays, including concentrations 64 × MIC in MDR‐MRSP1 isolates at 24 h, 32 × MIC in MDR‐MRSP2 at 48 h, 32 × MIC in MDR‐MRSP3 at 48 h and 256 × MIC in MDR‐MRSP3 at 24 h. Genome‐wide mutation analyses in these RFP‐resistant strains discovered the causal mutations in the coding region of therpoBgene.Conclusions and clinical relevanceA study has shown that 6 mg/kg per os results in plasma concentrations of 600–1,000 × MIC ofS. pseudintermedius. Based on our data, this dose should achieve the minimum MIC (×512) to prevent RFP resistance development; therefore, we recommend a minimum daily dose of 6 mg/kg for MDR‐MRSP pyoderma treatment when limited antibiotic options are available.
Mechanism of Ceramic-Like Friction of Quasicrystal-Reinforced Al Matrix Composites Formed by In Situ Directed Energy Deposition
Authors: Li Shuo , Mansori Mohamed El , Wang Qingzheng , Kang Nan , Hadrouz Mourad El 
Published: April 2021

Abstract
The wear of aluminum alloy may be decreased by its reinforcement with quasicrystals (QCs) prepared by melt, which in itself has good wear-resisting properties. This research paper considers the part played by a dense Al-Fe-Cr QC reinforced Al matrix composite fabricated by the directed energy deposition (DED) in reducing wear between sliding surfaces and discusses briefly some of the factors which, in practice, explain ceramic-like properties of quasicrystal including low friction and wear resistance. The hardness of reinforcement phases, QC Al91Fe4Cr5 and Al13(Fe, Cr)4, was up to ∼91 and ∼112 HV respectively, while the Al matrix was just ∼70 HV. Furthermore, the reinforcement phases contributed to form the mechanical mixing layer (MML) which significantly decreased the coefficient of friction (COF) and improves the wear resistance. With the increase of load from 1 N to 5 N, the COF dropped from 0.82 to 0.33 because the higher load was beneficial to the formation of harder and denser MML. Through the comprehensive analysis of the wear test and worn surface, the wear behavior and mechanism of this QC-reinforced Al matrix composite have been explained in detail. The results indicate that the quasicrystal-reinforced Al matrix composites formed by DED are one of the promising wear-resistance materials.
Mooring Analysis of a Dual-Spar Floating Wind Farm With a Shared Line
Authors: Liang Guodong , Jiang Zhiyu , Merz Karl 
Published: April 2021

AbstractWind farms with shared mooring lines have the potential to reduce mooring costs. However, such wind farms may encounter complex system dynamics because adjacent wind turbines are coupled. This paper presents an analysis of the shared mooring system with a focus on the system natural periods. We first apply Irvine’s method to model both the shared line and the two-segment single lines. The response surface method is proposed to replace iterations of the catenary equations of the single lines, and a realistic single line design is presented for OC3 Hywind. Then, system linearization and eigenvalue analysis are performed for the wind farm consisting of two spar floating wind turbines, one shared line, and four single lines. The obtained natural periods and natural modes are verified by numerical free decay tests. Finally, a sensitivity study is carried out to investigate the influence of mooring properties. It is found that the shared line has a significant influence on the natural periods in the surge and sway modes. The natural periods in the surge and sway modes are also most sensitive to the mooring property variations. Two sway eigenmodes are identified, and the lower sway natural period varies between 23 s and 88 s in the sensitivity study. The present analysis method can be used to identify critical natural periods at the preliminary design stage of shared mooring systems.
Dynamic Load and Contact Stress Analysis of Spur Gears
Authors: Arikan M. A. Sahir 
Published: April 2021

Abstract
Dynamic loads on spur gears are calculated by using an analytical model based on torsional vibrations of gears, and dynamic load variations during a mesh cycle of a tooth are determined. Variable stiffnesses of gear teeth, which are required for dynamic load calculations are found by using the finite element method. Contact stresses are calculated by using the analytical expressions developed for two elestic bodies held in contact by forces normal to the area of contact and accompanied by tangential (frictional) forces, and contact stress variations during a mesh cycle of a tooth are determined.
Feature Extraction for Casting Core Development
Authors: Ganter M. A. , Skoglund P. A. 
Published: April 2021

Abstract
Feature extraction techniques are presented for the generation of casting core patterns from a boundary representation (B-Rep) solid model. Techniques are presented which would allow for automatic extraction of three classes of core features (internal voids, single and multi-surface holes, and boundary perturbations). The task of extracting casting cores from solid models involves recognizing a collection of entities (i.e. slots, bosses, undercut surfaces, local and global concavities, etc.) from the set of lower level entities (i.e. the B-Rep structure). To this end, a combination of solid modeling B-Rep and graph structures and their associated methods will be used for casting core development. Appropriate local features are identified and extracted from the original object, and are grouped into one or more new object(s) (termed a core-object). If the core-object is multiply connected (i.e. composed of multiple objects), it is graph separated into global feature objects. Each of these global feature objects represents a core in the final pattern. Lastly, the geometry of the original part is augmented to add core prints where core geometries were extracted. The core print, as currently developed, combines the extracted core geometry and its convex hull.
A Geometry Based Method of Integrated Engineering Analysis and Optimization
Authors: Dolin Ronald M. , Bernhard Robert J. 
Published: April 2021

Abstract
An integrated geometry based method of analysis and optimization is presented. The significance of geometry based analysis and optimization methods are discussed. A hierarchical integer based data structure, used to define and manipulate geometry, is presented. Many features of the integer based data structure are given. Shapes are shown to represent the fundamental geometry. Variables of shapes are constrained and related to each other so that a reduced set of design variables result. These design variables are used to pose both analysis and optimization problems. Heuristics are used to simplify the integrated geometry specification, analysis and optimization procedures. The resulting engineering environment concurrently poses analysis and optimization problems during geometry generation, leading to an integrated geometry based method of analysis and optimization.
Synthesis of Spatially and Intrinsically Constrained Curves Using Simulated Annealing
Authors: Malhotra Alok , Oliver James H. , Tu Weizhen 
Published: April 2021

Abstract
A general technique is presented for automatic generation of B-spline curves in a spatially constrained environment, subject to specified intrinsic shape properties. Spatial constraints are characterized by a distance metric relating points on the curve to polyhedral models of obstacles which the curve should avoid. The shape of the curve is governed by constraints based on intrinsic curve properties such as parametric variation and curvature. To simultaneously address the independent goals of global obstacle avoidance and local control of intrinsic shape properties, curve synthesis is formulated as a combinatorial optimization problem and solved via simulated annealing. Several example applications are presented which demonstrate the robustness of the technique. The synthesis of both uniform and non-uniform B-spline curves is also demonstrated. An extension of the technique to general sculptured surface model synthesis is briefly described, and a preliminary example of simple surface synthesis presented.
Optimal Design With a Monomial-Based Version of Newton’s Method
Authors: Burns Scott A. 
Published: April 2021

Abstract
A monomial-based method for solving systems of algebraic nonlinear equations is presented. The method uses the arithmetic-geometric mean inequality to construct a system of monomial equations that approximates the system of nonlinear equations. This “monomial method” is closely related to Newton’s method, yet exhibits many special properties not shared by Newton’s method that enhance performance. These special properties are discussed in relation to engineering design optimization.
An Automatic Approach to Handling Inequality Constraints in an Interactive Design Environment
Authors: Sridhar Natarajan , Agrawal Rajiv , Kinzel Gary L. 
Published: April 2021

Abstract
A general mechanical design can be characterized by a set of equality and inequality constraints. Constraint Management algorithms have been successfully applied for the satisfaction of equality constraints. The goal of this paper is to extend the ideas of constraint management to handle inequality constraints. Past research shows that the handling of inequality constraints has been restricted to optimization and symbolic frameworks. As opposed to the traditional optimization schemes in which all the inequality constraints are converted to equalities, our approach introduces slack variables for only those inequalities that are active at that particular stage of the design process. The basic premise governing the algorithm presented in this paper is to satisfy a set of inequality constraints while deviating as little as possible from the given design specifications. An occurrence matrix formulation is used to represent both the equality and inequality constraints that govern the design. A linear model of the design, based on sensitivity computations, is used to automate the procedure. The work is illustrated for the classical weldment design problem.
A physical and chemical sedimentary record of Laramide tectonic shifts in the Cretaceous-Paleogene San Juan Basin, New Mexico, USA
Authors: Hobbs Kevin M. , Fawcett Peter J. 
Published: April 2021

Fluvial siliciclastic rocks bracketing the Cretaceous-Paleogene (K-Pg) boundary in the San Juan Basin, New Mexico (USA), provide records of regional fluvial and tectonic evolution during the Laramide orogeny. Petrographic analyses of sandstones from the Upper Cretaceous Fruitland Formation and Kirtland Formation and the Paleocene Ojo Alamo Sandstone and Nacimiento Formation show that the rivers depositing these sediments were sourced in areas where unroofing of crystalline basement rocks took place, introducing an increasing proportion of immature detrital grains into the fluvial system through time. After the Cretaceous-Paleogene boundary, rivers deposited an increasing amount of microcline and orthoclase feldspar relative to plagioclase feldspar, suggesting a growing source in unique crystalline basement rocks. Geochemical analyses show significant differences between Al- and K-poor Upper Cretaceous sandstones and Al- and K-rich lower Paleocene sandstones in the San Juan Basin.
The high proportion of sand-sized material in the Ojo Alamo Sandstone suggests that it was deposited in a basin with a low ratio of sediment supply to accommodation. However, magnetostratigraphic age constraints suggest it had a relatively high sedimentation and/or subsidence rate of as much as 0.38 m/k.y. The sediment supply must have been high in order to deposit a basin-wide coarse sand-dominated package, suggesting rapid creation of topographic relief in the San Juan uplift, the proposed source area of the Ojo Alamo fluvial system.
The observed sedimentary architecture and age constraints of the Ojo Alamo Sandstone, including kilometers-wide sand bodies and limited overbank mudstones throughout most of the outcrop area, are difficult to reconcile with accepted models of aggradation and avulsion in large fluvial systems, but available age and lithologic data make difficult a complete understanding of Paleocene San Juan Basin fluvial systems and basin evolution. Here, we present new lithologic, petrographic, and thickness data from San Juan Basin K-Pg fluvial siliciclastic units and interpretations of their origins.
Deactivation Mechanism of Palladium Catalysts for Ethanol
Conversion to Butanol
Authors: Ezzhelenko D. I. , Nikolaev S. A. , Chistyakov A. V. , Chistyakova P. A. , Tsodikov M. V. 
Published: April 2021

Abstract
A Pd/Al2O3 catalyst (Pd = 0.1 wt
%) for ethanol conversion to butanol deactivates within 10 h of service, despite
its high initial activity at 275°C. Probable deactivation mechanisms were
explored, including poisoning of
Pd/Al2O3 due to adsorption of
by-products on Pd, sintering of Pd phases, leaching of Pd from the catalyst,
changes in the Pd electronic state, changes in the catalyst’s porous structure,
and blockage of Al2O3 active
sites. The Pd/Al2O3 deactivation
was found to be mainly caused by CO molecules that evolved during side
reactions. These molecules can either block Pd active sites due to the formation
of strong Pd–CO complexes, or enter a CO disproportionation reaction to form
carbon deposits on Pd phases. The knowledge gained from this study can be used
for the targeted modification of
Pd/Al2O3 and the creation of
selective systems operating stably in the presence of by-products.
Risk model for intraoperative complication during cataract surgery based on data from 900 000 eyes: previous intravitreal injection is a risk factor
Authors: Hård af Segerstad Poya 
Published: April 2021

Background/aimsThe aim of this study was to develop a risk model for intraoperative complication (IC) during cataract surgery, defined as posterior capsule rupture and/or zonular dehiscence, and to include previous intravitreal therapy (pIVT) in the model.MethodsThis retrospective register-based study covered patients reported to the Swedish National Cataract Register (SNCR) between 1 January 2010 and 30 June 2018. Odds ratios (ORs) were used to quantify association strength of each variable with IC. Data from the SNCR were cross referenced with the Swedish Macula Register to include data on pIVT. Variables statistically significant in the univariate analyses (p<0.05) were included in a multivariate logistic regression model.ResultsThe inclusion criteria were met by 907 499 eyes. The overall rate of IC was 0.86%. Variables significantly associated with IC were best corrected visual acuity ≥1.0 LogMAR (OR (adjusted): 1.75, p<0.001), age ≥90 years (OR: 1.25, p<0.001), male sex (OR: 1.09, p<0.01), pseudoexfoliation (OR: 1.33, p<0.001), glaucoma (OR: 1.11, p<0.05), diabetic retinopathy (OR: 1.35, p<0.001), pIVT (OR: 1.45, p<0.05), surgeon’s experience <600 surgeries (OR: 2.77, p<0.001), use of rhexis hooks (OR: 6.14, p<0.001), blue staining (OR: 1.87, p<0.001) and mechanical pupil dilation (OR: 1.52, p<0.001).ConclusionThe risk model can be used in the preoperative setting to predict the probability of IC, to facilitate planning of surgery and improving patient communication. Patients who have undergone intravitreal therapy prior to cataract surgery have an increased risk of IC during cataract surgery.
Area under the dark adaptation curve as a reliable alternate measure of dark adaptation response
Authors: Pundlik Shrinivas , Nigalye Archana , Laíns Inês , Mendez Kevin M , Katz Raviv , Kim Janice , Kim Ivana K , Miller John B , Vavvas Demetrios , Miller Joan W , Luo Gang , Husain Deeba 
Published: April 2021

PurposeQuantification of dark adaptation (DA) response using the conventional rod intercept time (RIT) requires very long testing time and may not be measurable in the presence of impairments due to diseases such as age-related macular degeneration (AMD). The goal of this study was to investigate the advantages of using area under the DA curve (AUDAC) as an alternative to the conventional parameters to quantify DA response.MethodsData on 136 eyes (AMD: 98, normal controls: 38) from an ongoing longitudinal study on AMD were used. DA was measured using the AdaptDx 20 min protocol. AUDAC was computed from the raw DA characteristic curve at different time points, including 6.5 min and 20 min (default). The presence of AMD in the given eye was predicted using a logistic regression model within the leave-one-out cross-validation framework, with DA response as the predictor while adjusting for age and gender. The DA response variable was either the AUDAC values computed at 6.5 min (AUDAC6.5) or at 20 min (AUDAC20) cut-off, or the conventional RIT.ResultsAUDAC6.5 was strongly correlated with AUDAC20 (β=86, p<0.001, R2=0.87). The accuracy of predicting the presence of AMD using AUDAC20 was 76%, compared with 79% when using RIT, the current gold standard. In addition, when limiting AUDAC calculation to 6.5 min cut-off, the predictive accuracy of AUDAC6.5 was 80%.ConclusionsAUDAC can be a valuable measure to quantify the overall DA response and can potentially facilitate shorter testing duration while maintaining diagnostic accuracy.