Miracle-dz/UniFAR-FTUs huggingface dataset:
From microstructural features to effective toughness in disordered brittle solids

The relevant parameters at the microstructure scale that govern the macroscopic toughness of disordered brittle materials are investigated theoretically. We focus on a crack propagation that is planar and describe it as the motion of an elastic line within a plane with random distribution of toughness. Our study reveals two regimes: in the collective-pinning regime, the macroscopic toughness can be expressed as a function of a few parameters only, namely the average and the standard deviation of the local toughness distribution and the correlation lengths of the heterogeneous toughness field; in the individual-pinning regime, the passage from micro- to macro-scale is more subtle and the full distribution of local toughness is required to be predictive.
Novel application of focused ion beam electron microscopy (FIB-EM) in preparation and analysis of microfossil ultrastructures: A new view of complexity in early eukaryotic organisms

Abstract Coupled dual-beam focused ion beam electron microscopy (FIB-EM) has gained popularity across multiple disciplines over the past decade. Widely utilized as a stand-alone instrument for micromachining and metal or insulator deposition in numerous industries, the submicron-scale ion milling and cutting capabilities of FIB-EM systems have been well documented in the materials science literature. These capacities make FIB-EM a powerful tool for in situ, site-specific transmission electron microscopy (TEM) ultrathin foil preparation. Recent advancements in the field-emission guns (FEGs) of FIB-EM systems have provided spatial resolution comparable to that of many high-end scanning electron microscopes (SEM), thus providing enhanced imaging capacities with material deposition and material removal capabilities. More recently, FIB-EM preparation techniques have been applied to geological samples to characterize mineral inclusions, grain boundaries, and microfossils. Here, we demonstrate a novel method for analyzing three-dimensional (3-D) ultrastructures of microfossils using FIB-EM. Our method, FIB-EM nanotomography, consists of sequential ion milling, or cross sectioning, and concurrent SEM imaging. This technique with coupled dual-beam systems allows for real-time, 3-D ultrastructural analysis and compositional mapping with precise site selectivity and may provide new insights in fossil ultrastructures. Using the FIB-EM nanotomography method, we investigated herkomorphic and acanthomorphic acritarchs (organic-walled microfossils) extracted from the ≥999 Ma Mesoproterozoic Ruyang Group of North China. The 3-D characteristics of such important but controversial acritarch features as processes and vesicularly enclosed central bodies are described. Through these case studies, we demonstrate that FIB-EM nanotomography is a powerful and useful tool for investigating the three-dimensionality of microfossil ultra- and nanostructures.
Incentive-Based Entity Collection Using Crowdsourcing

Crowdsourced entity collection leverages human's ability to collect entities that are missing in a database, which has many real-world applications, such as knowledge base enrichment and enterprise data collection. There are several challenges. First, it is hard to evaluate the workers' quality because a worker's quality depends on not only the correctness of her provided entities but also the distinctness of these entities compared with the collected ones by other workers. Second, crowd workers are likely to provide popular entities and different workers will provide many duplicated entities, leading to a waste of money and low coverage. To address these challenges, we propose an incentive-based crowdsourced entity collection framework CrowdEC that encourages workers to provide more distinct items using an incentive strategy. CrowdEC has fundamental differences from existing crowdsourcing collection methods. One the one hand, CrowdEC proposes a worker model and evaluates a worker's quality based on cross validation and entity checking. CrowdEC devises a worker utility model that considers both worker's quality and entities' distinctness provided by workers. CrowdEC proposes a worker elimination method to block workers with a low utility, which solves the first challenge. On the other hand, CrowdEC proposes an incentive pricing technique that encourages each qualified (i.e., non-eliminated) worker to provide distinct entities rather than duplicates. CrowdEC provides two types of tasks and judiciously assigns workers with appropriate tasks to address the second challenge. We have conducted both real and simulated experiments, and the results show that CrowdEC outperforms existing state-of-the-art works on both cost and quality.
Is Liquidity Self‐Fulfilling?*

A security market where the relative incidence of informed and uninformed trading determines liquidity may have more than one equilibrium. Equilibrium with high liquidity has a low bid-ask spread. This increases participation by traders who want to hedge risk exposure, as opposed to trading on private information, and justifies the small price impact of trades. Equilibrium with low liquidity has a high bid-ask spread. This deters some hedgers, increasing the relative incidence of informed trading, which justifies the larger spread. This analysis casts doubt on the relevance of comparative statics results in the existing literature relying on exogenous liquidity traders.
Silicon and Carbon Isotopic Ratios in AGB Stars: SiC Grain Data, Models, and the Galactic Evolution of the Si Isotopes

Presolar SiC grains of the mainstream, Y, and Z type are believed to come from carbon stars. We compared their C and Si isotopic ratios with theoretical models for the envelope compositions of AGB stars. Two sets of models (FRANEC and Monash) use a range of stellar masses (1.5-5 M☉) and metallicities, different prescriptions for mass loss, and two sets of neutron-capture cross sections for the Si isotopes. They predict that the shifts in Si isotopic ratios and the increase of 12C/13C in the envelope during third dredge-up are higher for higher stellar mass, lower metallicity, and lower mass-loss rate. Because the 22Ne neutron source dominates Si nucleosynthesis, the effect of the 13C source is negligible. Comparison of the model predictions with grain data confirms an AGB origin for these grains, with Y and Z grains having originated in stars with lower than solar metallicity. The Si isotopic ratios of the Z grains favor the Si cross sections by Guber et al. over those by Bao et al. The 12C/13C ratios of low-metallicity models are much higher than those found in Z grains, and cool bottom processing must be invoked to explain the grains' C isotopic ratios. By combining Z grain Si data with the models, we determined the evolution of the 29Si/28Si ratio in the Galaxy as function of metallicity Z. At Z < 0.01 this ratio rises much faster than current Galactic evolution models predict and suggests an early source of the heavy Si isotopes not considered in these models.
Vegetation structure is as important as climate for explaining ecosystem function across Patagonian rangelands

Drylands cover about 41% of Earth's land surface, and 65% of their area supports domestic livestock that depends on the above‐ground net primary productivity (ANPP) of natural vegetation. Thus, understanding how biotic and abiotic factors control ANPP and related ecosystem functions can largely help to create more sustainable land‐use practices in rangelands, particularly in the context of ongoing global environmental change. We used 311 sites across a broad natural gradient in Patagonian rangelands to evaluate the relative importance of climate (temperature and precipitation) and vegetation structure (grass and shrub cover, species richness) as drivers of ANPP, precipitation‐use efficiency (PUE) and precipitation marginal response (PMR). Climatic variables explained 60%, 52% and 12% of the variation in grass cover, shrub cover and species richness, respectively. Shrub cover increased in areas with warmer, drier and winter rainfall climates, while the response observed for both grass cover and species richness was the opposite. Climate and vegetation structure explained 70%, 60% and 29% of the variation in ANPP, PUE and PMR, respectively. These three variables increased with increasing vegetation cover, particularly grass cover. Species richness also increased with ANPP, PUE and PMR. ANPP increased, and PUE decreased with increasing mean annual precipitation, whereas PMR increased with the proportion of precipitation falling in spring–summer. Temperature had a strong negative effect on ANPP and PUE, and a positive direct effect on PMR. Standardized total effects from structural equation modelling showed that vegetation structure and climate had similar strengths as drivers of ecosystem functioning. Grass cover had the highest total effect on ANPP (0.58), PUE (0.55) and PMR (0.41). Among the climatic variables, mean annual precipitation had the strongest total effect on ANPP (0.51) and PUE (−0.41), and the proportion of the precipitation falling in spring–summer was the most influential on PMR (0.36). Synthesis. Vegetation structure is as important as climate in shaping ecosystem functioning Patagonian rangelands. Maintaining and enhancing vegetation cover and species richness, particularly in grasses, could reduce the adverse effects of climate change on ecosystem functioning in these ecosystems.
Title: Domain-Specific Patterns of Activity Support Metacognition in Human Prefrontal Cortex Abbreviated title: Domain-Specific Metacognition in Prefrontal Cortex

170 words Introduction: 624 words Discussion: 973 words Acknowledgements: We thank Aurelio Cortese for his help with the MVPA analyses. This work was partially supported by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health (Grant No. R01NS088628) to H.L. and S.M. F. , by the Templeton Foundation (Grant No. 21569) to H.L. , and by a Sir Henry Wellcome Fellowship to S.M. F. (Grant No. WT096185). CC-BY-NC-ND 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not . http://dx.doi. org/10.1101/172445 doi: bioRxiv preprint first posted online Aug. 4, 2017;
The Northwest Africa (NWA) 5790 meteorite: A mesostasis‐rich nakhlite with little or no Martian aqueous alteration

Northwest Africa (NWA) 5790 is the most recently discovered member of the nakhlite group. Its mineralogy differs from the other nakhlites with a high abundance mesostasis (38.1 ± 3.6 vol%) and scarcity of olivine (4.0 ± 2.2 vol%). Furthermore, zoning of augite phenocrysts, and other petrographic and chemical characteristics suggest that NWA 5790 samples the chilled margin of its parent lava flow/sill. NWA 5790 contains calcite and rare clay minerals that are evidence for its exposure to liquid water. The calcite forms a cement to coatings of dust on the outer surface of the find and extends into the interior of the meteorite within veins. The presence of microbial remains within the coating confirms that the dust and its carbonate cement are terrestrial in origin, consistent with the carbon and oxygen isotope composition of the calcite. The clay minerals are finely crystalline and comprise ~0.003 vol% of the meteorite. δD values of the clay minerals range from −212 ± 109‰ to −96 ± 132‰, and cannot be used to distinguish between a terrestrial or Martian origin. As petrographic results are also not definitive, we conclude that secondary minerals produced by Martian groundwaters are at best very rare within NWA 5790. The meteorite has therefore sampled a region of the lava flow/sill with little or no exposure to the aqueous solutions that altered other nakhlites. This isolation could relate to the scarcity of olivine in NWA 5790 because dissolution of olivine in other nakhlites by Martian groundwaters enhanced their porosity and permeability, and provided solutes for secondary minerals.
Sex, Education and Procrastination: An Epidemiological Study of Procrastinators’ Characteristics from A Global Sample

Procrastination is a common form of self–regulatory failure with substantive connections to lower levels of health, wealth and well–being. Conducting an epidemiological study, we determined the characteristics of prototypical procrastinators from a global sample based on several relevant self–reported demographic variables. Using an internet sampling strategy, we surveyed 16 413 English–speaking adults (58.3% women; 41.7% men: M age = 38.3 years, SD = 14), specifically on the variables of sex, age, marital status, family size, education, community location, and national origin. Almost all the results were statistically significant because of our large sample size. However, procrastination tendencies were most prominently associated with sex, age, marital status, education and nationality. Procrastinators tended to be young, single men with less education, residing in countries with lower levels of self–discipline. Notably, procrastination mediated the relationship between sex and education, providing further support that men are lagging behind women academically because of lower self–regulatory skills. Given procrastination's connection with a variety of societal ailments (e.g. excessive debt, delayed medical treatment), identifying risk factors and at risk populations should be helpful for directing preventative public policy. Copyright © 2012 John Wiley & Sons, Ltd.
Design of Multi-Behavior Agents for Supply Chain Planning: An Application to the Lumber Industry

New economic challenges and recent trends regarding globalization have forced companies of many industries, including the Canadian lumber industry, to question aspects of their organizations. Many of them have looked to reengineer their organizational processes and business practices and adopt supply chain management best practices. An aspect studied by many researchers recently is supply chain sales and operations planning, which deals with the management of client orders through the supply chain. Each partner involved must decide quantities and production dates, and allocate resources for each product needed, with respect to production capacities and transportation delays. Coordination between production partners is essential in such a context in order to deliver products on time to final clients. As perturbations occur all the time in such complex system, production centers have to react quickly to correct deviances and create new plans, while coordinating changes with partners. At the structural level, centralized approaches handle supply chain planning and coordination with difficulty, mainly because of the complexity of such problems and the challenges of sharing private information between partners. Decentralized approaches are now being considered to overcome these problems, giving different partners the responsibility to locally plan their production, using coordination schemes to insure coherent supply chain behavior. Agent-based technology provides a natural approach to model supply chain networks and describe specialized planning agents. On the other hand, decentralized approaches are generally sub-optimal. Heuristics are used by agents to coordinate and optimize their production plan in order to reach feasible global solutions. Because a local change in a plan can impact other partners, a coordination mechanism must be used to insure that every partner is informed of the change and can make their own changes if necessary. Most of the time, system designers or production planners select a planning heuristic at design time, choosing what they believe to be the best decision for their specific application. The main problem is that the heuristic may not be adapted to further perturbations or environmental conditions the planning agents will face in a production context. Usually, these local algorithms used by agents can be parameterized on several levels (such as
A Stab in the Dark: A Case Report of an Atypical Presentation of Giant Cell Arteritis (GCA)

Background: Giant cell arteritis/temporal arteritis (GCA) is an inflammatory condition that affects large to medium vessels such as the aorta and its primary branches. Patients classically present with fatigue, fever, headache, jaw claudication and in severe cases, may suffer either transient (amaurosis fugax) or permanent visual loss. The reference standard for diagnosis is the temporal artery biopsy (TAB) and the mainstay of treatment is with immunosuppression. Our patient JG, presented with a range of non-specific symptoms that mimicked generalised sepsis, but was ultimately diagnosed with GCA through effective, methodical multi-disciplinary team (MDT) work. Clinical case: JG, an 81 year old gentleman, presented acutely with a 3–4 weeks history of fatigue, lethargy, pyrexia and a marked inflammatory response suggestive of a sepsis but without a clear primary source or clinical features of vasculitis. His inflammatory markers were markedly raised although his erythrocyte sedimentation rate (ESR) was not elevated. He was initially treated for sepsis of unknown origin however, body imaging after admission suggested a possible infection around a previous aortic graft site. This was refuted in subsequent 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET/CT) scanning. Microbiological, parasitic, as well as autoimmune assays were unremarkable. He underwent a TAB which was diagnostic for GCA and as a result, was started on oral corticosteroids with immediate symptom relief. He was discharged and followed up on an outpatient basis. Conclusions: This case highlights how a vasculitis can present with a range of non-specific symptoms that may resemble a fever of unknown origin (FUO)/sepsis that can lead to a delay in making the correct diagnosis. It also highlights the importance of considering a diagnosis of vasculitis in patients who present with a FUO where there is no clear focus of infection. Delays in diagnosis and management of these conditions can potentially lead to significant irreversible morbidity.
Semilandmarks: a method for quantifying curves and surfaces

Quantitative shape analysis using geometric morphometrics is based on the statistical analysis of landmark coordinates. Many structures, however, cannot be quantified using traditional landmarks. Semilandmarks make it possible to quantify two or three-dimensional homologous curves and sur- faces, and analyse them together with traditional landmarks. Here we first introduce the concept of sliding semilandmarks and discuss applications and limitations of this method. In a second part we show how the sliding semilandmark algorithm can be used to estimate missing data in incomplete specimens. Download the complete "Yellow Book" on "Virtual Morphology and Evolutionary Morphometrics in the new millenium".
Characterization and Determination of PM 2.5 Bound Polycyclic Aromatic Hydrocarbons (PAHS) in Indoor and Outdoor Air in Western Sierra Leone

Eleven airborne PM2.5 PAH concentrations were characterized in the kitchen, outdoor and living room environments in households that burn wood and charcoal fuels in Western Sierra Leone, during a survey that was conducted in September 2011. The average concentration of total PAHs (Σ11PAHs) was 1279.7 ng/m3 in kitchen, 41.2 ng/m3 in outdoor, 19.8 ng/m3 in living room for households burning wood while those burning charcoal was 96.5 ng/m3, 13.1 ng/ m3 and 8.9 ng/m3 in the kitchen, outdoor and living room, respectively. The percentage contribution of higher molecular weight PAHs to Σ11PAHs was about 25% higher compared to medium molecular weight PAHs for either household category in all three locations, with a somewhat different scenario for kitchens with wood stove. The ratio of indoor/ outdoor air of Σ11PAHs showed considerable variation among households burning charcoal (p=0.0021; t-test) relative to those burning wood, attributed to non-prolonged equilibrium between the two environments. Benzo(a)pyrene (BaP) equivalency results revealed that BaP and dibenzo(a,h)anthracene were the two most dominant compounds that contributed to more than 90% of the total carcinogenicity in all three environments for households burning wood and charcoal. The results suggest that kitchens, where biomass fuels are burnt continue to be a hazardous place for people of developing countries to spend their time.
Capacity Choice in a Price-Setting Mixed Duopoly with Network Effects

This paper explores the capacity choice for a public firm that is a welfare-maximizer and for a private firm that is a pure-profit-maximizer in the context of a price-setting mixed duopoly with a simple mechanism of network effects where the surplus that a firm’s client gets increases with the number of other clients of that firm. In this paper, we show that the public firm chooses over-capacity irrespective of the strength of network effects and the demand parameter, and that the difference between the output level and capacity level of the private firm strictly depends on the values of both the strength of network effects and the demand parameter. More precisely, the private firm chooses over-capacity when the strength of network effects is high relative to the demand parameter, while it chooses under-capacity otherwise.
The Adaptor Protein p66Shc Inhibits mTOR-Dependent Anabolic Metabolism

The adaptor protein p66Shc unexpectedly inhibits glucose metabolism, which could be a useful therapeutic target for diabetes or cancer. Negatively Adapting Metabolism Deficiency of the adaptor protein p66Shc, which inhibits signaling through receptor tyrosine kinases, improves the glucose tolerance of mice that are a genetic model of obesity. Soliman et al. found that in both transformed and nontransformed cells, p66Shc silencing enhanced glucose metabolism, increased the abundance of intermediates in various biosynthetic pathways, and increased cell size. The change in metabolism required the mTOR pathway, which couples energy, nutrient, and growth factor (including insulin) signals to processes that mediate cellular growth and proliferation. Thus, p66Shc suppresses mTOR signaling, and manipulating the abundance of p66Shc or interfering with p66Shc function could be used to treat diseases characterized by disruptions in this pathway, including diabetes and cancer. Adaptor proteins link surface receptors to intracellular signaling pathways and potentially control the way cells respond to nutrient availability. Mice deficient in p66Shc, the most recently evolved isoform of the Shc1 adaptor proteins and a mediator of receptor tyrosine kinase signaling, display resistance to diabetes and obesity. Using quantitative mass spectrometry, we found that p66Shc inhibited glucose metabolism. Depletion of p66Shc enhanced glycolysis and increased the allocation of glucose-derived carbon into anabolic metabolism, characteristics of a metabolic shift called the Warburg effect. This change in metabolism was mediated by the mammalian target of rapamycin (mTOR) because inhibition of mTOR with rapamycin reversed the glycolytic phenotype caused by p66Shc deficiency. Thus, unlike the other isoforms of Shc1, p66Shc appears to antagonize insulin and mTOR signaling, which limits glucose uptake and metabolism. Our results identify a critical inhibitory role for p66Shc in anabolic metabolism.