bluuebunny/crossref_metadata_2025_split huggingface dataset:
Marching volume polytopes algorithm
Authors: Byfut A. , Hellwig F. , Schröder A. 
Published: November 2018

SummaryThis paper presents an algorithm for the refinement of two‐ or three‐dimensional meshes with respect to an implicitly given domain, so that its surface is approximated by facets of the resulting polytopes. Using a Cartesian grid, the proposed algorithm may be used as a mesh generator. Initial meshes may consist of polytopes such as quadrilaterals and triangles, as well as hexahedrons, pyramids, and tetrahedrons. Given the ability to compute edge intersections with the surface of an implicitly given domain, the proposed marching volume polytopes algorithm uses predefined refinement patterns applied to individual polytopes depending on the intersection pattern of their edges. The refinement patterns take advantage of rotational symmetry. Since these patterns are applied independently to individual polytopes, the resulting mesh may encompass the so‐called orientation problem, where two adjacent polytopes are rotated against one another. To allow for a repeated application of the marching volume polytopes algorithm, the proposed data structures and algorithms account for this ambiguity. A simple example illustrates the advantage of the repeated application of the proposed algorithm to approximate domains with sharp corners. Furthermore, finite element simulations for two challenging real‐world problems, which require highly accurate approximations of the considered domains, demonstrate its applicability. For these simulations, a variant of the fictitious domain method is used.
Utilizing functionalized bromomaleimides for fluorogenic conjugation and PEGylation of enzymes
Authors: Husband Jonathan T , Hill Alice C , O'Reilly Rachel K 
Published: November 2018

AbstractTwo efficient enzyme conjugation techniques have been explored by exploiting the reactions of bromomaleimides. The conjugations utilize monobromo‐ and dibromomaleimides, which have been reacted with reduced disulfide bonds or terminal amines in α‐chymotrypsin and human lysozyme. These reactions allow the formation of dithio‐, monoamino‐ and aminobromomaleimides, which are solvent‐dependent fluorophores and have a handle for further functionalization, which allowed fluorogenic PEGylation via this technique. In this work, the efficiency of these maleimide conjugations was monitored and the fluorescence of the resulting conjugates was examined. The quantum yields of the small‐molecule maleimide conjugates were calculated, but are low due to solvent quenching effects. Catalytic activities of the conjugate enzymes were compared to those of their respective native enzymes, which show no discernible effect of the modifications on enzymatic activity or stability at room temperature. © 2018 Society of Chemical Industry
Spring flowering habit in field pennycress (Thlaspi arvense) has arisen multiple independent times
Authors: Dorn Kevin M. , Johnson Evan B. , Daniels Erin C. , Wyse Donald L. , Marks Michael D. 
Published: November 2018

AbstractField pennycress (Thlaspi arvense L.) is currently being developed as a new cold‐tolerant oilseed crop. In natural populations, pennycress, like many Brassicaceae relatives, can exhibit either a winter or spring annual phenotype. Pennycress is a diploid relative of Arabidopsis thaliana, a model species that has been used to study many adaptive phenotypes, including flowering time and developmental timing. In Arabidopsis and other Brassicaceae species, mutations in negative regulators of flowering, including FLOWERING LOCUS C and FRIGIDA can cause the transition to a spring annual habit. The genetics underlying the difference between spring and winter annual pennycress lines are currently unknown. Here, we report the identification of four natural alleles of FLC in pennycress that confer a spring annual growth habit identified through whole genome sequencing, cosegregation analyses, and comparative genomics. The global distribution of these spring annual alleles of FLC suggests that the spring annual growth habit has arisen on several independent occasions. The two spring annual FLC alleles present in European accessions were only identified in North American accessions collected in southern Montana, which indicates accessions harboring these two alleles were introduced to North America, likely after pennycress became a widespread species on the continent. These findings provide new information on the natural history of the introduction and spread of spring annual pennycress accessions from Europe into North America. At the molecular level, these findings are important for the ongoing development of pennycress as a winter annual crop. An enhanced understanding of the regulation of flowering in this species should allow for the fine‐tuning of flowering in commercial varieties.
Engineered SH2 domains with tailored specificities and enhanced affinities for phosphoproteome analysis
Authors: Veggiani Gianluca , Huang Haiming , Yates Bradley P. , Tong Jiefei , Kaneko Tomonori , Joshi Rakesh , Li Shawn S.C. , Moran Michael F. , Gish Gerald , Sidhu Sachdev S. 
Published: November 2018

AbstractProtein phosphorylation is the most abundant post‐translational modification in cells. Src homology 2 (SH2) domains specifically recognize phosphorylated tyrosine (pTyr) residues to mediate signaling cascades. A conserved pocket in the SH2 domain binds the pTyr side chain and the EF and BG loops determine binding specificity. By using large phage‐displayed libraries, we engineered the EF and BG loops of the Fyn SH2 domain to alter specificity. Engineered SH2 variants exhibited distinct specificity profiles and were able to bind pTyr sites on the epidermal growth factor receptor, which were not recognized by the wild‐type Fyn SH2 domain. Furthermore, mass spectrometry showed that SH2 variants with additional mutations in the pTyr‐binding pocket that enhanced affinity were highly effective for enrichment of diverse pTyr peptides within the human proteome. These results showed that engineering of the EF and BG loops could be used to tailor SH2 domain specificity, and SH2 variants with diverse specificities and high affinities for pTyr residues enabled more comprehensive analysis of the human phosphoproteome.StatementSrc Homology 2 (SH2) domains are modular domains that recognize phosphorylated tyrosine embedded in proteins, transducing these post‐translational modifications into cellular responses. Here we used phage display to engineer hundreds of SH2 domain variants with altered binding specificities and enhanced affinities, which enabled efficient and differential enrichment of the human phosphoproteome for analysis by mass spectrometry. These engineered SH2 domain variants will be useful tools for elucidating the molecular determinants governing SH2 domains binding specificity and for enhancing analysis and understanding of the human phosphoproteome.
Evaluating insecticide coverage in almond and pistachio for control of navel orangeworm (Amyelois transitella) (Lepidoptera: Pyralidae)
Authors: Siegel Joel P , Strmiska Mathew M , Niederholzer Franz JA , Giles D Ken , Walse Spenser S 
Published: November 2018

AbstractBACKGROUNDInsecticide application is essential to control navel orangeworm (Amyelois transitella) in California almond and pistachios. Coverage is difficult because of tree height and applicator practices. Studies were conducted to characterize insecticide deposition by both ground and air, and to develop alternatives to the use of water‐sensitive cards to assess spray coverage.RESULTSWe used almond challenge bioassays to demonstrate that insecticide application failed first in the upper canopy (5.2–6.1 m) when application speed exceeded 2.9 kph. In pistachios, we used filter paper and insecticide extraction from hulls to demonstrate that deposition increased with application volume. Typically, in ground applications, coverage decreased with height, whereas for application by air, coverage was greatest at the top of the canopy (6 m) and decreased as the spray penetrated the canopy. In the best ground applications there was no loss over height. We were able to demonstrate a dose–response relationship for methoxyfenozide using contact toxicity bioassays.CONCLUSIONCoverage was best at or below the recommended speed of 3.2 kph and improved when water volume increased. There was a 50% loss in insecticide efficacy at the height of 4–4.8 m; we suggest that future monitoring concentrate on this portion of the canopy. The best ground application provided uniform deposition throughout the canopy, whereas the applications by air were most effective in the upper canopy. The use of filter paper can provide information for chemical deposition and enable contact toxicity bioassays, whereas water‐sensitive paper cannot do this. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
Underperformance duration and innovative search: Evidence from the high‐tech manufacturing industry
Authors: Yu Wei , Minniti Maria , Nason Robert 
Published: November 2018

Research SummaryBehavioral theory examines how the intensity of underperformance influences firms' strategic decisions; yet, it largely fails to consider the effect of underperformance duration. Drawing on behavioral theory and organizational learning, we argue that the length of time that a firm has been underperforming contributes to shaping firms' innovative search patterns. We test our theory merging COMPUSTAT and NBER patent data for 1,610 high‐tech manufacturing companies between 1986 and 2006. Our results largely support our predicted curvilinear relationships. We find that innovative search magnitude and scope each first decreases and then increases with underperformance duration. In addition, we find marginal evidence that innovative search depth first increases and then decreases with underperformance duration. The statistical and practical significance of the results is also discussed.
Managerial SummaryInnovation is vital for a firm's survival and competitive advantage and requires a search for knowledge. Previous research suggests that the gap between current performance and desired performance is an important trigger for firms' innovative action. We suggest that how long the firm has been underperforming also plays an important role in firm innovation. Using financial and patent data on public high technology manufacturing firms, we show that there are nonlinear relationships between the duration of a firm's underperformance and its innovative activities. We find that underperforming firms first decrease and then increase R&D spending and the use of new knowledge as underperformance prolongs. Our results imply that underperforming firms face competing short‐ and long‐term pressures that influence the nature of its innovative activities.
From farms to fuel tanks: Stakeholder framing contests and entrepreneurship in the emergent U.S. biodiesel market
Authors: Hiatt Shon R. , Carlos W. Chad 
Published: November 2018

Research SummaryAlthough scholarship has demonstrated that market categories offer important signals to entrepreneurs about which goods and services are valued, little research has considered how entrepreneurs make sense of and exploit opportunities when contestation over category meaning persists. Using the emergent U.S. biodiesel market as a context, we present a framework to explain how the salience of different stakeholder frames shapes entrepreneurs' perceptions of market opportunities and influences their market‐entry strategies. By showing how framing contests affect entrepreneurial outcomes, this study illuminates the underlying cognitive mechanisms that impact market meaning and offers important implications for the literatures on entrepreneurship, market‐category evolution, framing contests, and grand challenges.Managerial SummaryEntrepreneurs entering new markets must consider how their products or services create value for customers. What customers value, however, is often shaped by competition between different stakeholders who seek to define problems and appropriate solutions. We argue and find that competing stakeholders influence what becomes valued in the market and shape the technologies and products developed by entrepreneurs. From the perspective of those promoting new markets, market growth requires a balancing act between maintaining control over market definitions and attracting new customers. In growing a new market, entrepreneurs and market pioneers may unintentionally attract other stakeholders who seek to alter or redefine market meanings, which can drive demand away from initial producers, foster the development and adoption of unforeseen technologies, and facilitate market entry of diverse organizations.
Pencil‐Drawing Skin‐Mountable Micro‐Supercapacitors
Authors: Zhu Sheng , Li Yitan , Zhu Huiyu , Ni Jiangfeng , Li Yan 
Published: November 2018

AbstractIn this study, integrated plaster‐like micro‐supercapacitors based on medical adhesive tapes are fabricated by a simple pencil drawing process combined with a mild solution deposition of MnO2. These solid micro‐supercapacitors not only exhibit excellent stretchability, flexibility, and biocompatibility, but also possess outstanding electrochemical performances, such as exceptional rate capability and cycling stability. Hence they may act as skin‐mountable and thin‐film energy storage devices of high efficiency to power miniaturized and wearable electronic devices.
The oldest members of Porcellioidea (Gastropoda): a new link between Baltica and Perunica
Authors: Frýda Jiří , Ebbestad Jan Ove R. , Frýdová Barbora 
Published: November 2018

AbstractThe strata of Gotland, Sweden, provide one of the richest records of Silurian gastropod faunas in the world. Recent re‐evaluation of museum collections revealed for the first time the presence of gastropods of the superfamily Porcellioidea (Archaeogastropoda) in the Silurian strata of Gotland (Baltica). Additionally, the porcellioideans from Gotland represent the oldest record of the superfamily, members of which were an element of marine gastropod communities from Silurian to Cretaceous time, a period of more than 350 million years. The morphology of the sinistrally coiled teleoconchs in the oldest porcellioidean gastropods supports an existing hypothesis that the pseudo‐bilaterally symmetrical teleoconch and the mid‐whorl position of the selenizone in the post‐Silurian porcelliids is a derived shell character. The occurrence of porcellioidean gastropods in the Silurian strata of Baltica also represents a new faunal link between Baltica and Perunica which corresponds well with published palaeobiogeographical and palaeogeographical models. Six taxa are described, including the Sheinwoodian (early Wenlock)Gotlandiela contraria(Lindström), the Gorstian (early Ludlow)Mannegaardina hedeigen. et sp. nov., the Ludfordian (late Ludlow)Gotlandielasp. andPernericirrus lindstroemisp. nov., as well as two agnesiid species.
Guideline Approaches for Cardioendocrine Disease Surveillance and Treatment Following Spinal Cord Injury
Authors: Nash Mark S. , Bilzon James L. J. 
Published: November 2018

AbstractPurpose of ReviewPersons with spinal cord injuries (SCI) commonly experience individual risks and coalesced health hazards of the cardiometabolic syndrome (CMS). This review will examinethe role of exercise and nutritional intervention as countermeasures to these disease risks.Recent FindingsThe CMS hazards of overweight/obesity, insulin resistance, hypertension, and dyslipidemia are strongly associated with physical deconditioning and are common after SCI. Both the CMS diagnosis and physical deconditioning worsen the prognosis for all-cause cardiovascular disease occurring early after SCI. Evidence supports a therapeutic role for physical activity after SCI as an effective countermeasure to these risks and often represents the first-line approach to CMS abatement. This evidence is supported by authoritative systematic reviews and associated guidelines that recommend specific activities, frequencies, and activities of work. In many cases, the most effective exercise programming uses more intense periods of work with limited rest. As SCI is also associated with poor dietary habits, including excessive energy intake and saturated fat consumption, more comprehensive lifestyle management incorporating both exercise and nutrition represents a preferred approach for overall health management.SummaryIrrespective of the interventional strategy, improved surveillance of the population for CMS risks and encouraged incorporation of exercise and nutritional management according to recent population-specific guidelines will most likely play an important role in the preservation of activity, optimal health, and independence throughout the lifespan.
Trajectory optimisation of six degree of freedom aircraft using differential flatness
Authors: Elango P. , Mohan R. 
Published: November 2018

ABSTRACTThe flatness of a six-degree-of-freedom (6DoF) aircraft model with conventional control surfaces – aileron, flap, rudder and elevator, along with thrust vectoring ability is established in this work. Trajectory optimisation of an aircraft can be cast as an inverse problem where the solution for control inputs that yield desired trajectories for certain states is sought. The solution to the inverse problems for certain systems is made tractable when they exhibit differential flatness. Flatness-based trajectory optimisation has a significant advantage over an equivalent collocation-based method in terms of computational efficiency and viability for real-time implementation. An application for the flatness of 6DoF aircraft is shown in the trajectory optimisation for dynamic soaring, and its connection with an equivalent 3DoF flatness-based implementation is also brought out. The results are compared with that from a collocation-based approach.
Provincial Differences in the Diagnosis and Care of Amyotrophic Lateral Sclerosis
Authors: Hodgkinson Victoria L. , Lounsberry Josh , Mirian Ario , Genge Angela , Benstead Timothy , Briemberg Hannah , Grant Ian , Hader Walter , Johnston Wendy S. , Kalra Sanjay , Linassi Gary , Massie Rami , Melanson Michel , O’Connell Colleen , Schellenberg Kerri , Shoesmith Christen , Taylor Sean , Worley Scott , Zinman Lorne , Korngut Lawrence 
Published: November 2018

AbstractBackground: Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease resulting in muscle weakness, dysarthria and dysphagia, and ultimately respiratory failure leading to death. Half of the ALS patients survive less than 3 years, and 80% of the patients survive less than 5 years. Riluzole is the only approved medication in Canada with randomized controlled clinical trial evidence to slow the progression of ALS, albeit only to a modest degree. The Canadian Neuromuscular Disease Registry (CNDR) collects data on over 140 different neuromuscular diseases including ALS across ten academic institutions and 28 clinics including ten multidisciplinary ALS clinics. Methods: In this study, CNDR registry data were analyzed to examine potential differences in ALS care among provinces in time to diagnosis, riluzole and feeding tube use. Results: Significant differences were found among provinces, in time to diagnosis from symptom onset, in the use of riluzole and in feeding tube use. Conclusions: Future investigations should be undertaken to identify factors contributing to such differences, and to propose potential interventions to address the provincial differences reported.
Low-Intensity Ultrasound Decreases Ischemia-Induced Edema by InhibitingN-Methyl-d-Aspartic Acid Receptors
Authors: Hada Binika , Karmacharya Mrigendra Bir , Park So R. , Choi Byung H. 
Published: November 2018

AbstractBackground:We have previously shown that low-intensity ultrasound (LIUS), a noninvasive mechanical stimulus, inhibits brain edema formation induced by oxygen and glucose deprivation (OGD) or treatment with glutamate, a mediator of OGD-induced edema, in acute rat hippocampal slice modelin vitro.Methods:In this study, we treated the rat hippocampal slices withN-methyl-d-aspartic acid (NMDA) or (S)-3,5-dihydroxyphenylglycine (DHPG) to determine whether these different glutamate receptor agonists induce edema. The hippocampal slices were then either sonicated with LIUS or treated withN-methyl-d-aspartic acid receptor (NMDAR) antagonists, namely, MK-801 and ketamine, and observed their effects on edema formation.Results:We observed that treatment with NMDA, an agonist of ionotropic glutamate receptors, induced brain edema at similar degrees compared with that induced by OGD. However, treatment with DHPG, an agonist of metabotropic glutamate receptors, did not significantly induce brain edema. Treatment with the NMDAR antagonists MK-801 or ketamine efficiently prevented brain edema formation by both OGD and NMDA in a concentration-dependent manner.N-Methyl-d-aspartic acid-induced brain edema was alleviated by LIUS in an intensity-dependent manner when ultrasound was administered at 30, 50, or 100 mW/cm2for 20 minutes before the induction of the edema. Furthermore, LIUS reduced OGD- and NMDA-induced phosphorylation of NMDARs at Y1325.Conclusion:These results suggest that LIUS can inhibit OGD- or NMDA-induced NMDAR activation by preventing NMDAR phosphorylation, thereby reducing a subsequent brain edema formation. The mechanisms by which LIUS inhibits NMDAR phosphorylation need further investigation.
Endoscopic Retrieval of Flanged Ventricular Catheters
Authors: Babadagli M. Ege , Cooke Dwaine , Walling Simon A. , McNeely P. Daniel 
Published: November 2018

AbstractFlanged ventricular catheters are now used infrequently. Many patients with longstanding hydrocephalus still harbor these catheters, either as their current ventricular catheter, or as a retained catheter from a prior implant. The removal of flanged ventricular catheters is sometimes necessary, and may be challenging due to intraventricular adhesions. We describe the use of an endoscopic technique for the successful retrieval of flanged ventricular catheters in two patients. The technique described in this report may be helpful for patients that have flanged ventricular catheters that must be removed.
Maps in People’s Heads: Assessing a New Measure of Context
Authors: Wong Cara , Bowers Jake , Rubenson Daniel , Fredrickson Mark , Rundlett Ashlea 
Published: November 2018

AbstractTo understand the relationship between place and politics, we must measure both political attitudes and the ways in which place is represented in the minds of individuals. In this paper, we assess a new measure of mental representation of geography, in which survey respondents draw their own local communities on maps and describe them. We use a panel study in Canada to present evidence that these maps are both valid and reliable measures of a personally relevant geographic area, laying the measurement groundwork for the growing number of studies using this technology. We hope to set efforts to measure “place” for the study of context and politics on firmer footing. Our validity assessments show that individuals are thinking about people and places with which they have regular contact when asked to draw their communities. Our reliability assessments show that people can draw more or less the same map twice, even when the exercise is repeated months later. Finally, we provide evidence that the concept of community is a tangible consideration in the minds of ordinary citizens and is not simply a normative aspiration or motivation.