cssi/SciSciGPT-SciSciNet huggingface dataset:
Extremal feature extraction from 3-D vector and noisy scalar fields

We are interested in feature extraction from volume data in terms of coherent surfaces and 3D space curves. The input can be an inaccurate scalar or vector field, sampled densely or sparsely on a regular 3D grid, in which poor resolution and the presence of spurious noisy samples make traditional iso-surface techniques inappropriate. In this paper, we present a general-purpose methodology to extract surfaces or curves from a digital 3D potential vector field {(s,v~)}, in which each voxel holds a scalar s designating the strength and a vector v~ indicating the direction. For scalar, sparse or low-resolution data, we "vectorize" and "densify" the volume by tensor voting to produce dense vector fields that are suitable as input to our algorithms, the extremal surface and curve algorithms. Both algorithms extract, with sub-voxel precision, coherent features representing local extrema in the given vector field. These coherent features are a hole-free triangulation mesh (in the surface case), and a set of connected, oriented and non-intersecting polyline segments (in the curve case). We demonstrate the general usefulness of both extremal algorithms on a variety of real data by properly extracting their inherent extremal properties, such as (a) shock waves induced by abrupt velocity or direction changes in a flow field, (b) interacting vortex cores and vorticity lines in a velocity field, (c) crest-lines and ridges implicit in a digital terrain map, and (d) grooves, anatomical lines and complex surfaces from noisy dental data.
High resolution large format tile-scan camera: Design, calibration, and extended depth of field

Emerging applications in virtual museums, cultural heritage, and digital art preservation require very high quality and high resolution imaging of objects with fine structure, shape, and texture. To this end we propose to use large format digital photography. We analyze and resolve some of the unique challenges that are presented by digital large format photography, in particular sensor-lens mismatch and extended depth of field. Based on our analysis we have designed and built a digital tile-scan large format camera capable of acquiring high quality and high resolution images of static scenes. We also developed calibration techniques that are specific to our camera as well as a novel and simple algorithm for focal stack processing of very large images with significant magnification variations.
Formation of α,ω-dienes upon photooxidation of alkenyl carbyne complexes

Abstract Photolysis of the alkenyl carbyne complexes (η5–C5H5)(CO){P(OMe)3}Mo≡CCH2(CH2)nCHCH2 (n=2 (1b), 3 (1c) and 4 (1d)) in CHCl3 results in the formation of the corresponding α,ω-dienes CH2CH(CH2)nCHCH2. Also produced are the dichloromolybdenum carbynes (η5–C5H5)Cl2{P(OMe)3}Mo≡C–CH2(CH2)nCHCH2 (n=2 (8b), 3 (8c), and 4 (8d)). Both sets of products arise following the generation of highly reactive 17-electron complexes via photochemical electron transfer from 1b–d to the solvent. These radical cations either undergo H-abstraction at the carbyne carbon followed by H-shift to form the dienes or they undergo exchange of Cl− for the CO ligand and Cl-abstraction at the metal to yield 8b–d. The product ratios reflect partitioning of the 17-electron species between reactivity at the metal center vs. the carbyne carbon.
Sapphire substrate-bonded ultra-low threshold 850 nm VCSEL array

Oxide-confined vertical-cavity surface-emitting laser (VCSEL) 8/spl times/8 arrays were fabricated and off set flip-chip bonded onto sapphire substrates. These devices were further wire bonded in pin-grid-array (PGA) packages as optical transmitters. Optical output of the top-emitting 850 nm VCSEL array was transmitted through the transparent sapphire substrate. Lasing threshold as low as 24 /spl mu/A was found from some of these devices at room temperature.
A finite mixture distribution approach for characterizing tree diameter distributions by natural social class in pure even-aged Scots pine stands in Poland

The overall diameter distribution of an even-aged stand can be treated as a compound of distributions of trees belonging to various classes. The presented study shows the applicability of a finite mixture distribution approach for describing diameter structure of such classes on an example of pure, even-aged Scots pine stands. We performed our study under an assumption that all starting values for parameter fitting should be available as a result of a routine forest inventory. When the parameters of the mixture are fitted to the unimodal distributions without any constraints, this approach often fails. This is because components of such distributions strongly overlap, and the fact of overlapping falsifies information about individual components. For a mixture forming a unimodal distribution, due to difficulties in fitting, it is necessary to use functions that exhibit certain skewness and are relatively flexible, such as lognormal or gamma. There is also a need for providing better start information, keeping certain parameters fixed, or using a multi-stage fitting. Despite possible problems with fitting parameters to the strongly overlapping distributions, this approach shows much potential in practical applications in silviculture and growth and yield modeling.
The Complex Morphology of a New Lower Silurian Asteroid (Echinodermata)

Gordonaster brassfieldensis is a new genus and species of Asteroidea (Echinodermata) described from the Lower Silurian Brassfield Formation of east-central Kentucky. Tentatively assigned to the poorly understood Palaeasteridae, Gordonaster shares much with Ordovician asteroids, yet it also exhibits apparent homoplasies that presage the post-Paleozoic crown group. Available specimens also indicate that the ontogenetic pattern of ossicular addition seen in the crown group was established during the Paleozoic.
Pigs: Behavior and Welfare Assessment

Compromised welfare leads to reduction in productivity and market forces can have negative effects when the welfare is shown to be poor. Thus, compromised animal welfare affects the economic sustainability of animal agriculture in more than one way. Without objective quantification, a compromise in welfare cannot be approved nor can the efficacy of corrective measures be assessed. Behavioral changes are the first and obvious indicators of compromised welfare in animals, though the identification of the same requires thorough knowledge about the normal behavior of the species concerned.
Simulating Cl diffusion in polycrystalline CdTe

Most theoretical treatments of grain boundary (GB) diffusion start with the model developed by Fisher over sixty years ago, where a bulk material with a low diffusion constant is bisected by a narrow slab with high diffusivity (the GB). For this system, Fisher derived two coupled differential equations, the second involving a first order derivative. While Fisher's model can be applied to more general situations, it can be very cumbersome to implement in cases where the GBs are only piecewise linear and/or intersect at arbitrary angles. In this work, we develop an alternate model involving only second order derivatives that is more conducive to simulating arbitrary GB geometries, but yields results that are equivalent to those one would obtain from Fisher's. We apply our model to the problem of Cl diffusion in CdTe, using it to obtain Cl concentration profile data that is similar to those obtained in recent experiments.
Articulated Motion Learning via Visual and Lingual Signals

In order for robots to operate effectively in homes and workplaces, they must be able to manipulate the articulated objects common to environments built for and by humans. Previous work learns kinematic models that prescribe this manipulation from visual demonstrations. Lingual signals, such as natural language descriptions and instructions, offer a complementary means of conveying knowledge of such manipulation models and are suitable to a wide range of interactions (e.g., remote manipulation). In this paper, we present a multimodal learning framework that incorporates both visual and lingual information to estimate the structure and parameters that define kinematic models of articulated objects. The visual signal takes the form of an RGB-D image stream that opportunistically captures object motion in an unprepared scene. Accompanying natural language descriptions of the motion constitute the lingual signal. We present a probabilistic language model that uses word embeddings to associate lingual verbs with their corresponding kinematic structures. By exploiting the complementary nature of the visual and lingual input, our method infers correct kinematic structures for various multiple-part objects on which the previous state-of-the-art, visual-only system fails. We evaluate our multimodal learning framework on a dataset comprised of a variety of household objects, and demonstrate a 36% improvement in model accuracy over the vision-only baseline.
Law, Expertise and Political Economy in Twentieth Century Egypt

One of the enduring verities of the study of law and social change in Egypt (and many other parts of North Africa, the Middle East, South Asia and Southeast Asia) is that European legal codes, one of many tools of colonial control, forcibly displaced Islamic law in the late 19th and early 20th centuries. In this essay I propose that, at least in Egypt, codification based on Continental European models, had significant support from important indigenous economic and social interests as well as being a project of the colonial or the domestic state. In the context of debates about comparative law in the late 19th and early 20th in which Egyptians took part, Roman or codified law had three important advantages relative to common law or judge-made law which made it progressive. It embodied popular sovereignty and it privileged social-scientific expertise. Its third advantage derived from these first two: it ensured that legal training created a corps of state officials who would impose law rather than advocates who would represent opposing interests in the arena of courtroom.
The SEC's Regulation A-Plus: Small Business Goes Under the Bus Again

Title IV of the JOBS Act, which is entitled "Small Company Capital Formation," requires the Securities and Exchange Commission to adopt new rules regarding offerings under Regulation A. The Commission has now adopted its final regulations implementing Title IV and providing a new regulatory regime for exempt offerings under Section 3(b) of the Securities Act of 1933. The new regime is generally referred to as Regulation A-Plus.Unfortunately, history and empirical data regarding the use of Regulation A and Regulation D strongly suggest that the final Regulation A-Plus rules are unlikely to provide any material relief for small businesses in their difficult search for efficient sources of external capital. Instead, the exemption provided by Regulation A-Plus will likely be attractive only to larger businesses that are not currently reporting companies under the Securities Exchange Act of 1934.To a significant extent, this outcome is the result of an effective campaign mounted by state securities regulators, prosecuted through their trade association, the North American Securities Administrators Association (NASAA), and enabled by the Securities and Exchange Commission (Commission). Once again, NASAA – aided and abetted by the Commission – effectively blocked small businesses from a fair and efficient path to external capital, destroying an important component of the JOBS Act that was specifically designed to facilitate small business capital formation.In the vernacular of the day, small businesses were – again – thrown under the bus.
How large should my study be so that I can detect an altered sex ratio

The world literature on manipulations purported to alter the gender of offspring is a quagmire full of reports presenting inadequate data and contradictory conclusions. Many are due to inappropriate statistical design or analysis. The authors present simple, nontechnical reference tables for determination of the minimum sample size necessary to detect a change in sex ratio (1) from a theoretical value, and (2) between two experimental populations. Simple methods for analyzing the results of gender manipulation experiments are described. Technical details are included in a separate section.
A graph-based approach for semantic data mining

Data mining is the nontrivial extraction of implicit, previously unknown, and potentially useful information from data. It is widely acknowledged that the role of domain knowledge in the discovery process is essential. However, the synergy between domain knowledge and data mining is still at a rudimentary level. This motivates me to develop a framework for explicit incorporation of domain knowledge in a data mining system so that insights can be drawn from both data and domain knowledge. I call such technology "semantic data mining." Recent research in knowledge representation has led to mature standards such as the Web Ontology Language (OWL) by the W3C's Semantic Web initiative. Semantic Web ontologies have become a key technology for knowledge representation and processing. The OWL ontology language is built on the W3C's Resource Description Framework (RDF) that provides a simple model to describe information resources as a graph. On the other hand, there has been a surge of interest in tackling data mining problems where objects of interest can be best described as a graph of interrelated nodes. I notice that the interface between domain knowledge and data mining can be achieved by using graph representations. Therefore I explore a graph-based approach for modeling both knowledge and data and for analyzing the combined information source from which insight can be drawn systematically. In summary, I make three main contributions in this dissertation to achieve semantic data mining. First, I develop an information integration solution based on metaheuristic optimization when data mining task require accessing heterogeneous data sources. Second, I describe how a graph interface for both domain knowledge and data can be structured by employing the RDF model and its graph representations. Finally, I describe several graph theoretic analysis approaches for mining the combined information source. I showcase the utility of the proposed methods on finding semantically associated itemsets, a particular case of the frequent pattern mining. I believe these contributions in semantic data mining can provide a novel and useful way to incorporate domain knowledge. This dissertation includes published and unpublished coauthored material.
RHEED study of the surface structure of Cu(110) from 153 to 973 K

We have studied the surface structure of Cu(110) from 153 to 973 K. Reflection high energy electron diffraction (RHEED) was employed to analyze the surface modifications taken place at the crystal surface. We performed careful spot profile intensity measurements as a function of temperature.The typical characteristics of forward scattering, the short wavelength at high energy, and the small grazing incidence angle in RHEED provide strong surface sensitivity and are therefore ideal to study surface structures and especially surface roughness. We observe at low temperatures strong diffraction streaks in the patterns as well as Kikuchi lines. The diffraction intensities reduce slowly when the temperature is raised from 153 K to 473 K, then fall off more rapidly after that, and from 573 K, the intensities decrease drastically. High resolution LEED measurements indicate a reduction in the coherence length at high temperatures.
Large-eddy simulation of chaotic convection and beyond

Subgrid modeling for the scalar transport equation and for the incompressible Navier-Stokes equations is considered. It is shown that, for the case of scalar transport, a tensor diffusivity may be derived from first principles for many applications. However, this diffusivity can be locally strongly anti-diffusive, so that the filtered transport equation is ill-conditioned. A rationale for regularizing the equation is presented that relies on a careful choice of the numerical method used to solve the transport equation. Two such schemes are derived - an anisotropic particle scheme and a wavelet-based scheme. In addition, it is argued that analogous terms should appear in the filtered Navier-Stokes equations. (Author)
Carol Ann Muller and Sathima Bea Benjamin. Musical Echoes: South African Women T hinking in Jazz. Durham: Duke UP, 2011

Musical Echoes is the result of a rare collaboration. Carol Ann Muller, an ethnomusicologist, and Sathima Bea Benjamin, an Emmy nominated jazz singer and composer, are both from South Africa. They ...
On the Lagrange Remainder of the Taylor Formula

(1982). On the Lagrange Remainder of the Taylor Formula. The American Mathematical Monthly: Vol. 89, No. 5, pp. 311-312.
Promotion Expectations and Preference for the Protean or Promised Path: A Survey Instrument Approach

This study develops a survey instrument structure that generates many stylized findings in the literature and in preliminary tests passes theoretical litmus tests for robustness of estimates of preference for the protean or promised path of career advancement. Embedded in the study is an empirical structure that enables estimates of promotion expectations that can be different for employees with identical job tenure, experience, or education. In so far as instruments are concerned, the study shows employees' responses towards firm mandated training inferred from Principal Factor analysis are indicators of preference for the protean or promised path of career advancement. Empirical results demonstrate the latent factor generated by the structure within the survey instrument enables cross-sectional, as opposed to longitudinal predictions implied by employee tenure; that is, facilitates comparisons of employees with exactly the same tenure within organizations.
Determination of nabam fungicide in crops by liquid chromatography with postcolumn reaction detection

The ethylenebisdithiocarbamate (EBDC) fungicide, nabam, was determined in several crop matrixes using liquid chromatography with postcolumn reaction detection. After separation by micellar liquid chromatography, nabam (EBDC sodium salt) was acid hydrolyzed to ethylenediamine and fluorigenically labeled with o-phthalaldehyde-mercaptoethanol (OPA-MERC). Standard curves were linear from the detection limit of ca 1 ng to 1000 ng. Nabam was recovered in high yield (89 plus or minus 7.7%) over a range of concentrations (0.1 to 20 ppm) from fortified samples of papaya, lettuce, cucumber, spinach, and applesauce using a simple extraction method. Efforts to convert the more popular EBDC fungicides, maneb and mancozeb, to nabam are discussed.
Regional cerebral glucose metabolism in bulimia nervosa.

Objective: The authors’ purpose in this study was to further delineate the character of cerebral metabolism in bulimia nervosa and to determine if functional links could be made between regional cerebral metabolism and the symptoms ofdepression, obsessive-compulsive disorder, and bulimia nervosa. Method: Regional cerebral glucose metabolism was measured by using positron emission tomography in 1 1 inpatients with bulimia nervosa and 1 8 normal comparison subjects matched in sex (all were women), age, and educational level. The bulimic patients were also tested for symptoms ofmajor depression and obsessive-compulsive disorder. Results: The patients with bulimia showed a correlation between lower left anterolateral pref rontal regional cerebral glucose metabolism and greater depressive symptoms. However, the orbitofrontal regional cerebral glucose metabolism of patients with bulimia was not greater than that of comparison subjects, nor was higher orbitofrontal metabolism correlated with greater obsessive-compulsive disorder symptoms. Conclusions: These findings lead to the conclusion that left anterior lateral prefrontal cortex hypometabolism varies with the depressive symptoms observed in bulimia but that temporal lobe hypermetabolism and asymmetries appear to be independent of the mood state. (Am J Psychiatry 1992; 149:1506-15 13)
Trans-Fatty Acids: Health Effects, Recommendations, and Regulations

There are distinct differences in the isomeric distribution of trans -fatty acids from industrially produced versus natural sources, which may translate to differential effects on health outcomes. There is a vast literature that demonstrates the deleterious effects of industrially produced trans -fatty acids on chronic disease risk, including cardiovascular disease, cancer, and diabetes; however, the health effects of ruminant trans -fatty acids in humans have not been well studied. Trans fats alternatives have been useful in reducing trans fats in the food supply; however, their health effects are not yet well understood, thus further research is warranted.
The Smart Citizen Factor in Trustworthy Smart City Crowdsensing

Several studies on Internet-of-Things (IoT)-based sensor data collection and portable sensing techniques have been reported for smart city monitoring via built-in sensors of smart mobile devices. A key question in smart city crowdsensing is how to ensure the usefulness or value of the data collected from citizens in a participatory manner. Related work proposes maintaining distributed user reputation databases to overcome malicious attempts or persistent sensor errors. This article provides a survey of the state of the art in reputation-based crowdsensing in smart cities by revisiting remarkable solutions to collect and analyze data from mobile devices. Furthermore, the authors present a novel vote-based reputation-aware user-recruitment approach that unveils the impact of collaborative trustworthiness assessment with anchor smart citizens. They provide useful insight toward future directions, open issues, and challenges in this area.
National Trends in the Use of Neoadjuvant Chemotherapy for Hormone Receptor-Negative Breast Cancer: A National Cancer Data Base Study.

Background Neoadjuvant chemotherapy (NAC) downstages tumor size and nodal disease. This study evaluates national practice patterns of NAC use in hormone receptor-negative breast cancer.
Embedded Real-Time Operating Systems

This chapter covers embedded real-time operating systems (RTOS). It introduces the concepts and requirements of real-time systems. It covers the various kinds of task scheduling algorithms in RTOS, which include RMS, EDF and DMS. It explains the problem of priority inversion due to preemptive task scheduling. It describes the schemes to prevent priority inversion by priority ceiling and priority inheritance. It includes case studies of several popular real-time OS and presents a set of general guidelines for RTOS design. It shows the design and implementation of a UP_RTOS for uniprocessor (UP) systems. Then it extends the UP_RTOS to a SMP_RTOS, which supports nested interrupts, preemptive task scheduling, priority inheritance and inter-processor synchronization by SGI.
Rapid and dynamic arginylation of the leading edge β-actin is required for cell migration

β-actin plays key roles in cell migration. Our previous work demonstrated that β-actin in migratory non-muscle cells is N-terminally arginylated and that this arginylation is required for normal lamellipodia extension. Here, we examined the function of β-actin arginylation in cell migration. We found that arginylated β-actin is concentrated at the leading edge of lamellipodia and that this enrichment is abolished after serum starvation as well as in contact-inhibited cells in confluent cultures, suggesting that arginylated β-actin at the cell leading edge is coupled to active migration. Arginylated actin levels exhibit dynamic changes in response to cell stimuli, lowered after serum starvation and dramatically elevating within minutes after cell stimulation by readdition of serum or lysophosphatidic acid. These dynamic changes require active translation and are not seen in confluent contact-inhibited cell cultures. Microinjection of arginylated actin antibodies into cells severely and specifically inhibits their migration rates. Together, these data strongly suggest that arginylation of β-actin is a tightly regulated dynamic process that occurs at the leading edge of locomoting cells in response to stimuli and is integral to the signaling network that regulates cell migration.
Pilcher, Jeffrey M. Planet Taco: A Global History of Mexican Food Oxford: Oxford University Press 320 pp., $27.95, ISBN 978-0-19-974006-2 Publication Date: October 2012

In a 2017 interview with the journal Gastronomica, the renowned agrarian studies scholar James C. Scott suggested that the study of food opened new doors to new audiences. “If you do a conference o...
Design and implementation of pragmatic clinical trials using the electronic medical record and an adaptive design.

Objectives To demonstrate the feasibility of pragmatic clinical trials comparing the effectiveness of treatments using the electronic medical record (EMR) and an adaptive assignment design. Methods We have designed and are implementing pragmatic trials at the point-of-care using custom-designed structured clinical documentation support and clinical decision support tools within our physician's typical EMR workflow. We are applying a subgroup based adaptive design (SUBA) that enriches treatment assignments based on baseline characteristics and prior outcomes. SUBA uses information from a randomization phase (phase 1, equal randomization, 120 patients), to adaptively assign treatments to the remaining participants (at least 300 additional patients total) based on a Bayesian hierarchical model. Enrollment in phase 1 is underway in our neurology clinical practices for 2 separate trials using this method, for migraine and mild cognitive impairment (MCI). Results We are successfully collecting structured data, in the context of the providers' clinical workflow, necessary to conduct our trials. We are currently enrolling patients in 2 point-of-care trials of non-inferior treatments. As of March 1, 2018, we have enrolled 36% of eligible patients into our migraine study and 63% of eligible patients into our MCI study. Enrollment is ongoing and validation of outcomes has begun. Discussion This proof of concept article demonstrates the feasibility of conducting pragmatic trials using the EMR and an adaptive design. Conclusion The demonstration of successful pragmatic clinical trials based on a customized EMR and adaptive design is an important next step in achieving personalized medicine and provides a framework for future studies of comparative effectiveness.
A Preliminary Study on the Role of Movement Imagery in Spatial Perception

According to dance theory, dancers are uniquely aware of the relationship between the environment and their body, making them a type of spatial expert. Inherent in their practice are the abilities to assess the location of other people, objects and the environment relative to their body, and to use movement imagery. The current study tests if dancers perceive the world differently than non-dancers. To test this, dancers performed a battery of spatial tasks (egocentric and exocentric distance estimates, a height judgment, and affordance judgments, i.e., perceived vertical and horizontal passability, stepability, and jumpability) and completed paper-and-pencil spatial ability tests. Dancers differed from non-dancers in their movement imagery ability but superior imagery ability did not result in greater accuracy in imagined distance estimates. Height judgments were overestimated in both groups but less so in dancers. Dancers were found to be, on average, less conservative in their affordance judgments than non-dancers.
Using natural language processing on the free text of clinical documents to screen for evidence of homelessness among US veterans.

Information retrieval algorithms based on natural language processing (NLP) of the free text of medical records have been used to find documents of interest from databases. Homelessness is a high priority non-medical diagnosis that is noted in electronic medical records of Veterans in Veterans Affairs (VA) facilities. Using a human-reviewed reference standard corpus of clinical documents of Veterans with evidence of homelessness and those without, an open-source NLP tool (Automated Retrieval Console v2.0, ARC) was trained to classify documents. The best performing model based on document level work-flow performed well on a test set (Precision 94%, Recall 97%, F-Measure 96). Processing of a naive set of 10,000 randomly selected documents from the VA using this best performing model yielded 463 documents flagged as positive, indicating a 4.7% prevalence of homelessness. Human review noted a precision of 70% for these flags resulting in an adjusted prevalence of homelessness of 3.3% which matches current VA estimates. Further refinements are underway to improve the performance. We demonstrate an effective and rapid lifecycle of using an off-the-shelf NLP tool for screening targets of interest from medical records.
Forest Nutrient Cycling: Toxic Ions

Nutrients must move into, within, and out of forest ecosystems in appropriate amounts, at appropriate rates, and along established pathways for normal forest growth to occur. The two major sources of nutrients for temperate forest ecosystems are (a) meteorologic input of dissolved, particulate, and gaseous chemicals from outside the ecosystem; and (b) release by weathering of nutrients from primary and secondary minerals stored within the ecosystem (Bormann and Likens, 1979). Healthy forest ecosystems conserve these nutrients and continually recycle them through the system via an elaborate litterfall-decomposition-uptake intrasystem cycle.
Thrombospondin expression in traumatized skeletal muscle. Correlation of appearance with post-trauma regeneration.

Biochemical and immuno-microscopic techniques were used to study temporal involvement of thrombospondin in relation to fibrinogen in muscle regeneration using a rat skeletal muscle-wound model. In undamaged control muscle, no fibrinogen and minimal thrombospondin antigen was found. Following crushing injury, fibrin networks appear immediately, followed by a gradual ordered accumulation of thrombospondin (within a few hours) in the vicinity of the vascular bed and adjacent endomysial connective tissue. Later, thrombospondin becomes associated with connective tissue and basal laminae around muscle fibers throughout the damaged muscle, maximal labelling occurring 3–6 days post-injury. Thrombospondin immunoreactivity decreased thereafter to near normal levels after 7 days post-injury, coincident with the appearance of regenerating muscle fibers. In contrast, little fibrin material remained by five days after injury. Quantitative radioimmunoassay of soluble thrombospondin antigen and radioimmune labelling of thick frozen sections reinforced the qualitative immuno-microscopic observations, with levels peaking at 3–4 days post-trauma, 10-fold over control levels. SDS-PAGE immunoblotting of non-reduced muscle extracts three days after a crush assault shows that the bulk of the thrombospondin incorporated into the injury site exists in a polymerized state (≤1000 kD). These results demonstrate that the temporal appearance and disappearance of thrombospondin in the healing of a crushing lesion in muscle is related more closely to the regeneration phase of muscle than to the coagulation phase.
Magnetic excitations in the quasi-two-dimensional ferromagnet Fe 3 -x GeTe 2 measured with inelastic neutron scattering

${\mathrm{Fe}}_{3\ensuremath{-}x}{\mathrm{GeTe}}_{2}$ is an itinerant ferromagnet composed of two-dimensional layers weakly connected by van der Waals bonding that shows a variety of intriguing phenomena. Inelastic neutron scattering measurements on bulk single crystals of ${\mathrm{Fe}}_{2.75}{\mathrm{GeTe}}_{2}$ were performed to quantify the magnetic exchange interaction energies and anisotropy. The observed inelastic excitations, which extend to a maximum energy of $\ensuremath{\sim}75$ meV, are indicative of dominant in-plane correlations with negligible magnetic interactions between the layers. A spin gap of 3.7 meV is observed, allowing a measure of the magnetic anisotropy. The excitations are damped, reflective of both the magnetic site occupancy reduction of 25% on one Fe sublattice and the itinerant interactions. A minimal model is employed to describe the excitation spectra and extract magnetic exchange interaction values. The temperature evolution of the excitations are probed and correlations shown to persist above ${T}_{c}$, further supporting the low-dimensional nature of the magnetism.
Precalculus as a Death Sentence for Engineering Majors: A Case Study of How One Student Survived

Few college students wanting to major in an engineering discipline who begin in precalculus actually complete an undergraduate engineering degree program. One reason for this is students struggle through calculus I and II, known barrier courses for engineering majors. This research utilizes frameworks of future time perspective (FTP) and self-regulated learning (SRL) to explore one successful student’s experience as he struggled through his mathematics courses, but was able to overcome those struggles and graduate with an engineering degree. A case study was constructed around this student, using quantitative data from his mathematics and engineering courses, as well as qualitative data in the form of an open-ended survey and interviews. A mathematics instructor, who modeled self-regulation strategies as he served as the student’s mentor, was key to his success in passing the required courses in the calculus sequence. A model of interactions between FTP and SRL was developed based on an existing model and insights from this case study. By understanding the experience of one of the few successful students, educators are better equipped to assist other students and increase the number of students persisting in engineering, which will help address the global need for more engineers.
Impacts of process-induced porosity on material properties of copper made by binder jetting additive manufacturing

Abstract Binder Jetting (BJ) is an efficient, economical, and scalable Additive Manufacturing (AM) technology that can be used in fabricating parts made of reflective and conductive materials like copper, which have applications in advanced thermal and electrical components. The primary challenge of BJ is in producing fully dense, homogeneous parts without infiltration. To this end, copper parts of porosities ranging from 2.7% to 16.4% were fabricated via BJ, by varying powder morphology, post-process sintering, and Hot Isostatic Pressing conditions. The aim of this study is to characterize and quantify the effects of porosity on the material properties of Binder Jet pure copper parts. Copper parts with the lowest porosity of 2.7% demonstrated a tensile strength of 176 MPa (80.2% of wrought strength), a thermal conductivity of 327.9 W/m·K (84.5% that of wrought copper), and an electrical conductivity of 5.6 × 107 S/m (96.6% IACS). The porosity-property relationship in these parts was compared against theoretical and empirical models in the literature for similar structures. These studies contribute towards developing a scientific understanding of the process-property-performance relationship in BJ of copper and other printed metals, which can help in tailoring materials and processing conditions to achieve desired properties.
The Republic of Arabic Letters: Islam and the European Enlightenment: by Alexander Bevilacqua, Cambridge, MA, Belknap Press of Harvard University Press, 2018, $35.00/£27.95 (cloth)

In this book, Alexander Bevilacqua presents us with a lucid, erudite, and in many respects engaging study of a dimension of the European Enlightenment and its precursor traditions that has not prev...
Electrospray Ionization–Based Synthesis and Validation of Amine-Sulfuric Acid Clusters of Relevance to Atmospheric New Particle Formation

Atmospheric new particle formation (NPF) is the process by which atmospheric trace gases such as sulfuric acid, ammonia, and amines cluster and grow into climatically relevant particles. The mechanism by which these particles form and grow has remained unclear, in large part due to difficulties in obtaining molecular-level information about the clusters as they grow. Mass spectrometry–based methods using electrospray ionization (ESI) as a cluster source have shed light on this process, but the produced cluster distributions have not been rigorously validated against experiments performed in atmospheric conditions. Ionic clusters are produced by ESI of solutions containing the amine and bisulfate or by spraying a sulfuric acid solution and introducing trace amounts of amine gas into the ESI environment. The amine content of clusters can be altered by increasing the amount of amine introduced into the ESI environment, and certain cluster compositions can only be made by the vapor exchange method. Both approaches are found to yield clusters with the same structures. Aminium bisulfate cluster distributions produced in a controlled and isolated ESI environment can be optimized to closely resemble those observed by chemical ionization in the CLOUD chamber at CERN. These studies indicate that clusters generated by ESI are also observed in traditional atmospheric measurements, which puts ESI mass spectrometry–based studies on firmer footing and broadens the scope of traditional mass spectrometry experiments that may be applied to NPF.
Tau-Cofactor Complexes as Building Blocks of Tau Fibrils.

The aggregation of the human tau protein into neurofibrillary tangles is directly diagnostic of many neurodegenerative conditions termed tauopathies. The species, factors and events that are responsible for the initiation and propagation of tau aggregation are not clearly established, even in a simplified and artificial in vitro system. This motivates the mechanistic study of in vitro aggregation of recombinant tau from soluble to fibrillar forms, for which polyanionic cofactors are the most commonly used external inducer. In this study, we performed biophysical characterizations to unravel the mechanisms by which cofactors induce fibrillization. We first reinforce the idea that cofactors are the limiting factor to generate ThT-active tau fibrils, and establish that they act as templating reactant that trigger tau conformational rearrangement. We show that heparin has superior potency for recruiting monomeric tau into fibril compared to any constituent intermediate or aggregate “seeds”. We show that tau and cofactors form intermediate complexes whose evolution toward ThT-active fibrils is tightly regulated by tau-cofactor interactions. Remarkably, it is possible to find mild cofactors that complex with tau without forming ThT active species, except when an external catalyst (e.g. a seed) is provided to overcome the energy barrier. In a cellular context, we propose the idea that tau could associate with cofactors to form a metastable complex that remains “inert” and reversible, until encountering a relevant seed that can trigger an irreversible transition to -sheet containing species.
A new perspective on the open-path infrared gas analyzer self-heating correction

Abstract Across networks of cold weather sites, eddy covariance measurements of ecosystem fluxes commonly indicate carbon uptake throughout winter, a problem that has been linked to open-path infrared gas analyzer (IRGA) self-heating. Though there is no definitive consensus about this phenomenon, the de facto correction for the prevalent LI-7500 is the methodology of Burba et al. (2008) (B08), which predicts self-heating from IRGA surface temperatures and boundary layers. In this paper we examine the validity of this model compared to an updated correction by conducting field studies with the LI-7500 and an IRGA designed by the National Oceanic and Atmospheric Administration (NOAA). Both types of sensors were instrumented to measure sensible heat flux within the instrument path and temperatures of key instrument surfaces. We test hypotheses that (1) considerable IRGA self-heating occurs at a cold, windy, high elevation, mountainous field site, (2) unwarranted boundary layer adjustment terms defined in B08 reduce the bottom and top surface heat fluxes by an order of magnitude, and (3) the weighted sum of the surface heat fluxes should be proportional to their surface area contribution to the IRGA measurement volume. We detected more sensible heat flux within the LI7500 path than outside of it (statistical slopes between 0.95 to 1.3 and offsets between 0 and 35 W m−2) with the largest discrepancies occurring during the day and in winter. The NOAA IRGA has a similar structure to the LI-7500, but with flat surfaces that do not warrant the boundary layer adjustment terms in B08. Bayesian analyses indicated the bottom and top surface heat flux weightings from B08 are improbable and an order of magnitude too large. For the LI-7500, when the boundary layer adjustment terms were omitted the B08 weightings were also improbable; by including these terms and using the new weightings, self-heating estimates were reasonable only because the bottom and top sensible heat fluxes became negligible. We conclude that it is likely the B08 self-heating correction has two errors that roughly cancel out at our field site; this should not generally be expected. The new formulation emphasizes the role of the spar in self-heating, which should be taken into consideration for all cold-weather installations regardless of how the IRGA is mounted.
Response to: 'Increasing incidence of autoantibody-negative RA is replicated and is partly explained by an aging population' by Matthijssen et al.

We thank Matthijssen and colleagues for their interest in our study on the epidemiology of rheumatoid arthritis (RA), where we have reported a significant increase in incidence of rheumatoid factor (RF)-negative RA and a decrease in RF-positive RA in 2005–2014 compared with previous decades.1 Matthijssen et al have independently assessed the incidence of anticitrullinated peptide antibody (ACPA)-negative and ACPA-positive RA in the Leiden Early Arthritis Cohort. In concordance with our findings, they found increasing incidence of ACPA-negative RA but not ACPA-positive RA.2 Further, Matthijssen et al …
A New User-Configurable Method to Improve Short-Circuit Ruggedness of 1.2-kV SiC Power MOSFETs

Silicon carbide (SiC) power MOSFETs have been commercialized to replace silicon insulated gate bipolar transistors (IGBTs) in power conversion applications. However, the short-circuit ruggedness of SiC power MOSFETs must be enhanced to match that of Si IGBTs for application in motor drives for electric vehicles. A new, user-configurable method with a series-connected, Si enhancement mode MOSFET (EMM) is demonstrated to improve the short-circuit withstand time of commercially available 1.2-kV SiC power MOSFETs by 86% with a 4.2% increase in on- resistance and a 13% increase in switching loss. In contrast, operating the 1.2-kV SiC power MOSFET with a reduced gate bias of 15 V produces an 80% improvement in short-circuit withstand time with 31% increase in on- resistance and a 31% increase in switching loss. It is demonstrated that the drain of the EMM can be used as a sensing node to monitor on- state current and to detect short-circuit events.
Stakeholder perspectives on raptor conservation and falconry in North America

Abstract Global raptor conservation depends on non-governmental conservation organizations (NGCOs) and, fundamentally, members of those organizations. But while NGCOs declare a central mission, their membership may be more varied. This can pose a challenge to a NGCO in terms of developing programs and advocacy that reflects its membership’s preference and likelihood of support. Systematic assessment of members’ preferences and opinions is needed to assure alignment with an organization’s actions. Using the North American Falconers Association (NAFA) as a NGCO case study, members’ preferences and opinions on issues related to raptor conservation were assessed. Results suggest a consensus among participants that conservation should include habitats and species; prairie, sage, and wetland habitats are the most salient habitat issues and perceived declines in native game bird, waterfowl, and small game mammals are the most salient wildlife issues. Tied to these concerns of habitat and species was land access to practice falconry. Overall, results suggest participants prefer organizational resources be used to support prairie habitat and grouse species conservation. For NGCOs, systematic membership surveys can provide substantial insight for decision-making and effective allocation of membership-derived resources. Member surveys also signal an organizations willingness to listen to its constituents and act upon their views and local knowledge to coordinate conservation action.
Reorganizing the Federal Clemency Process

The President relies on the Department of Justice to filter out ineligible applicants and recommend from the remainder which ones should receive clemency, but the department suffers from an actual or apparent conflict of interest. One proposed remedy would be for Congress to create an independent advisory board like the U.S. Sentencing Commission to review every clemency application and offer the President its recommendations. A better alternative would be for the President to move the Office of the Pardon Attorney into the Executive Office of the President and use the Vice President as his principal clemency adviser. The Vice President can offer the President several benefits in the clemency decision-making process that no one else in the government possesses.
Botany and the woman colonizer in Catharine Parr Traill's Backwoods of Canada and Anna Brownell Jameson's Winter Studies and Summer Rambles in Canada

This essay explores the gendered dynamics of settler belonging in Catharine Parr Traill's Backwoods of Canada and Anna Brownell Jameson's Winter Studies and Summer Rambles in Canada. Settlement for...
Emission properties and temperature dependence of Cu+ luminescence in the CaO-CaF2-P2O5 ternary glass system co-doped with CuO and SnO

Abstract Co-doping of the (50−x)CaO–xCaF2–50P2O5 (x=0,10, and 20) ternary glass system with CuO and SnO has been realized by the melt-quenching technique with the purpose of investigating on material photoluminescence (PL). The glasses display tunable luminescence by variation of excitation wavelength in connection with the distinct excitation/emission properties of Cu+ ions and Sn centers. Substitution of CaO by CaF2 appeared to support the Cu+ luminescence process. Analyses of emission decay dynamics suggest that both luminescent species exist primarily coordinated to oxygen atoms in the oxyfluorophosphate hosts. Further, the effect of temperature on Cu+ PL was evaluated from room temperature to 300 °C. An increase in the activation energy for the thermal quenching of Cu+ PL was observed upon the substitution of oxygen by fluorine ions. Accordingly, the Cu+-doped oxyfluorophosphate matrix shows potential as thermally-stable glass for optical device applications (e.g. lighting, solar cells).