Estimating the frequency of coincidental spatial associations between Clovis artifacts and proboscidean remains in North America

2021 ◽  
pp. 1-11
Author(s):  
Madeline E. Mackie ◽  
Randall Haas

Abstract The extent to which Clovis peoples hunted proboscideans is debated. Convention requires that for a proboscidean butchery site to be accepted, contemporaneous artifacts must be spatially associated with faunal remains, and there must be evidence of use of the remains. Fourteen sites in North America currently meet those criteria; at least 31 do not. While these are reasonable requirements for avoiding false positives, such an approach risks identifying false negatives—rejecting spatial associations that are systemic associations. Given the known distributions of Clovis and proboscidean sites, how likely is it that artifacts are coincidentally associated with proboscidean remains? Conversely, how many spatial associations could be unrecognized butchery sites? To answer these questions, we simulated chance associations by plotting empirically informed densities and sizes of archaeological and proboscidean sites on simulated landscapes in which people and animals are (a) uniformly distributed and (b) tethered to water sources. The simulated frequencies of coincidental associations were compared to the observed frequency of co-occurrences. Our results suggest that of the 31 indeterminate empirical associations, at least 17 and as many as 26 are likely systemic associations, more than doubling previous estimates and revealing a greater role of humans in Pleistocene proboscidean exploitation than previously recognized.

2020 ◽  
Vol 2020 (14) ◽  
pp. 378-1-378-7
Author(s):  
Tyler Nuanes ◽  
Matt Elsey ◽  
Radek Grzeszczuk ◽  
John Paul Shen

We present a high-quality sky segmentation model for depth refinement and investigate residual architecture performance to inform optimally shrinking the network. We describe a model that runs in near real-time on mobile device, present a new, highquality dataset, and detail a unique weighing to trade off false positives and false negatives in binary classifiers. We show how the optimizations improve bokeh rendering by correcting stereo depth misprediction in sky regions. We detail techniques used to preserve edges, reject false positives, and ensure generalization to the diversity of sky scenes. Finally, we present a compact model and compare performance of four popular residual architectures (ShuffleNet, MobileNetV2, Resnet-101, and Resnet-34-like) at constant computational cost.


2020 ◽  
Author(s):  
Stuart Yeates

A brief introduction to acronyms is given and motivation for extracting them in a digital library environment is discussed. A technique for extracting acronyms is given with an analysis of the results. The technique is found to have a low number of false negatives and a high number of false positives. Introduction Digital library research seeks to build tools to enable access of content, while making as few as possible assumptions about the content, since assumptions limit the range of applicability of the tools. Generally, the broader the assumptions the more widely applicable the tools. For example, keyword based indexing [5] is based on communications theory and applies to all natural human textual languages (allowances for differences in character sets and similar localisation issues not withstanding) . The algorithm described in this paper makes much stronger assumptions about the content. It assumes textual content that contains acronyms, an assumption which is known to hold for...


2021 ◽  
pp. 1-20
Author(s):  
Michael Phillipp Brunner

Abstract The 1920s and 30s were a high phase of liberal missionary internationalism driven especially by American-led visions of the Social Gospel. As the missionary consensus shifted from proselytization to social concerns, the indigenization of missions and the role of the ‘younger churches’ outside of Europe and North America was brought into focus. This article shows how Protestant internationalism pursued a ‘Christian Sociology’ in dialogue with the field’s academic and professional form. Through the case study of settlement sociology and social work schemes by the American Marathi Mission (AMM) in Bombay, the article highlights the intricacies of applying internationalist visions in the field and asks how they were contested and shaped by local conditions and processes. Challenging a simplistic ‘secularization’ narrative, the article then argues that it was the liberal, anti-imperialist drive of the missionary discourse that eventually facilitated an American ‘professional imperialism’ in the development of secular social work in India. Adding local dynamics to the analysis of an internationalist discourse benefits the understanding of both Protestant internationalism and the genesis of Indian social work and shows the value of an integrated global micro-historical approach.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 395
Author(s):  
Héctor D. Menéndez ◽  
David Clark ◽  
Earl T. Barr

Malware detection is in a coevolutionary arms race where the attackers and defenders are constantly seeking advantage. This arms race is asymmetric: detection is harder and more expensive than evasion. White hats must be conservative to avoid false positives when searching for malicious behaviour. We seek to redress this imbalance. Most of the time, black hats need only make incremental changes to evade them. On occasion, white hats make a disruptive move and find a new technique that forces black hats to work harder. Examples include system calls, signatures and machine learning. We present a method, called Hothouse, that combines simulation and search to accelerate the white hat’s ability to counter the black hat’s incremental moves, thereby forcing black hats to perform disruptive moves more often. To realise Hothouse, we evolve EEE, an entropy-based polymorphic packer for Windows executables. Playing the role of a black hat, EEE uses evolutionary computation to disrupt the creation of malware signatures. We enter EEE into the detection arms race with VirusTotal, the most prominent cloud service for running anti-virus tools on software. During our 6 month study, we continually improved EEE in response to VirusTotal, eventually learning a packer that produces packed malware whose evasiveness goes from an initial 51.8% median to 19.6%. We report both how well VirusTotal learns to detect EEE-packed binaries and how well VirusTotal forgets in order to reduce false positives. VirusTotal’s tools learn and forget fast, actually in about 3 days. We also show where VirusTotal focuses its detection efforts, by analysing EEE’s variants.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Renato Farina ◽  
Pietro Valerio Foti ◽  
Andrea Conti ◽  
Francesco Aldo Iannace ◽  
Isabella Pennisi ◽  
...  

AbstractVascular compression syndromes are rare alterations that have in common the compression of an arterial and/or venous vessel by contiguous structures and can be congenital or acquired. The best known are the Thoracic Outlet Syndrome, Nutcracker Syndrome, May–Thurner Syndrome, and Dunbar Syndrome. The incidence of these pathologies is certainly underestimated due to the non-specific clinical signs and their frequent asymptomaticity. Being a first-level method, Ultrasound plays a very important role in identifying these alterations, almost always allowing a complete diagnostic classification. If in expert hands, this method can significantly contribute to the reduction of false negatives, especially in the asymptomatic population, where the finding of the aforementioned pathologies often happens randomly following routine checks. In this review, we briefly discuss the best known vascular changes, the corresponding ultrasound anatomy, and typical ultrasound patterns.


2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S35-S36
Author(s):  
Hadrian Mendoza ◽  
Christopher Tormey ◽  
Alexa Siddon

Abstract In the evaluation of bone marrow (BM) and peripheral blood (PB) for hematologic malignancy, positive immunoglobulin heavy chain (IG) or T-cell receptor (TCR) gene rearrangement results may be detected despite unrevealing results from morphologic, flow cytometric, immunohistochemical (IHC), and/or cytogenetic studies. The significance of positive rearrangement studies in the context of otherwise normal ancillary findings is unknown, and as such, we hypothesized that gene rearrangement studies may be predictive of an emerging B- or T-cell clone in the absence of other abnormal laboratory tests. Data from all patients who underwent IG or TCR gene rearrangement testing at the authors’ affiliated VA hospital between January 1, 2013, and July 6, 2018, were extracted from the electronic medical record. Date of testing; specimen source; and morphologic, flow cytometric, IHC, and cytogenetic characterization of the tissue source were recorded from pathology reports. Gene rearrangement results were categorized as true positive, false positive, false negative, or true negative. Lastly, patient records were reviewed for subsequent diagnosis of hematologic malignancy in patients with positive gene rearrangement results with negative ancillary testing. A total of 136 patients, who had 203 gene rearrangement studies (50 PB and 153 BM), were analyzed. In TCR studies, there were 2 false positives and 1 false negative in 47 PB assays, as well as 7 false positives and 1 false negative in 54 BM assays. Regarding IG studies, 3 false positives and 12 false negatives in 99 BM studies were identified. Sensitivity and specificity, respectively, were calculated for PB TCR studies (94% and 93%), BM IG studies (71% and 95%), and BM TCR studies (92% and 83%). Analysis of PB IG gene rearrangement studies was not performed due to the small number of tests (3; all true negative). None of the 12 patients with false-positive IG/TCR gene rearrangement studies later developed a lymphoproliferative disorder, although 2 patients were later diagnosed with acute myeloid leukemia. Of the 14 false negatives, 10 (71%) were related to a diagnosis of plasma cell neoplasms. Results from the present study suggest that positive IG/TCR gene rearrangement studies are not predictive of lymphoproliferative disorders in the context of otherwise negative BM or PB findings. As such, when faced with equivocal pathology reports, clinicians can be practically advised that isolated positive IG/TCR gene rearrangement results may not indicate the need for closer surveillance.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Georg Ferber ◽  
Ulrike Lorch ◽  
Jörg Täubel

Concentration-effect (CE) models applied to early clinical QT data from healthy subjects are described in the latest E14 Q&A document as promising analysis to characterise QTc prolongation. The challenges faced if one attempts to replace a TQT study by thorough ECG assessments in Phase I based on CE models are the assurance to obtain sufficient power and the establishment of a substitute for the positive control to show assay sensitivity providing protection against false negatives. To demonstrate that CE models in small studies can reliably predict the absence of an effect on QTc, we investigated the role of some key design features in the power of the analysis. Specifically, the form of the CE model, inclusion of subjects on placebo, and sparse sampling on the performance and power of this analysis were investigated. In this study, the simulations conducted by subsampling subjects from 3 different TQT studies showed that CE model with a treatment effect can be used to exclude small QTc effects. The number of placebo subjects was also shown to increase the power to detect an inactive drug preventing false positives while an effect can be underestimated if time points aroundtmaxare missed.


1989 ◽  
Vol 3 (3) ◽  
pp. 254-264 ◽  
Author(s):  
Stephen J. Bull

This article presents a case study describing the contribution of a sport psychology consultant to an ultra-distance runner’s attempt to complete 500 miles (800 kilometers) in 20 days through the deserts of North America. The contribution can be considered in four phases that provide a descriptive framework for the role of a sport psychology consultant: (a) establishing a rapport with the athlete, (b) formulating a psychological profile, (c) evaluating the demands of the athletic pursuit and planning an appropriate mental training program, and (d) ongoing evaluation of progress and crisis intervention.


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