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We consider two-loop corrections to 2 → 2 scattering processes with massive particles in the final state and massive particles in the loop. We discuss the combination of analytic expansions in the high-energy limit and for small Mandelstam variable t. For the example of double Higgs boson production we show that the whole phase space can be covered and time-consuming numerical integrations can be avoided. [ABSTRACT FROM AUTHOR]

This paper discusses some of the earliest Modern English translations of Beowulf to assess how these authors have affected scholarship surrounding masculinity. By assessing the violent and emotional elements of early Victorian translation, I am able to unveil how English nationalism is injected into the poem wherever possible. Such behaviours have been carried forth as the pinnacle of Anglo-Saxon or Germanic masculinity, with little room left to assess the contradicting behaviours such as Hrothgar's shedding of tears or his settlement of feuds with gold instead of brute force. By conducting a close reading of the selected translations, namely John Mitchell Kemble and Benjamin Thorpe, I can identify elements of masculine-coded behaviours that translators have attempted to alter in order to construct a more consistently violent rhetoric in critical male characters, such as Beowulf, Hrothgar, and Wiglaf. This has had a profound effect on scholarship which, until the 1990s, excluded any major studies of masculinity, having been deemed too obvious to merit attention. By considering translation choices, we can further explore how masculinity is constructed within the poem and how these choices shape such identities. These translations are compared to one another using Bosworth-Toller online, as, by using a dictionary that was first published in the nineteenth-century, we can contrast translation choices within the confines of their contemporaries where possible, revealing the translators' own self-interests and political ideologies that continue to bleed into twenty-first-century reception and scholarship. [ABSTRACT FROM AUTHOR]

The sources of isotopically light carbon released during the end-Triassic mass extinction remain in debate. Here, we use mercury (Hg) concentrations and isotopes from a pelagic Triassic–Jurassic boundary section (Katsuyama, Japan) to track changes in Hg cycling. Because of its location in the central Panthalassa, far from terrigenous runoff, Hg enrichments at Katsuyama record atmospheric Hg deposition. These enrichments are characterized by negative mass independent fractionation (MIF) of odd Hg isotopes, providing evidence of their derivation from terrestrial organic-rich sediments (Δ199Hg < 0‰) rather than from deep-Earth volcanic gases (Δ199Hg ~ 0‰). Our data thus provide evidence that combustion of sedimentary organic matter by igneous intrusions and/or wildfires played a significant role in the environmental perturbations accompanying the event. This process has a modern analog in anthropogenic combustion of fossil fuels from crustal reservoirs. Mercury (Hg) concentrations and isotopes from a deep-ocean Triassic–Jurassic (~201 Ma) boundary section provide evidence of large inputs from terrestrial organic-rich sources through combustion by magmatic sills and wildfires. [ABSTRACT FROM AUTHOR]

We present fully differential next-to-leading order results for Higgs production in association with a Z boson in gluon fusion. Our two-loop virtual contributions are evaluated numerically using sector decomposition, including full top-quark mass effects, and supplemented at high pT by an analytic high-energy expansion to order m Z 4 , m H 4 , m t 32 . Using the expanded results we also present a study of the top-quark mass scheme uncertainty at large pT. [ABSTRACT FROM AUTHOR]

We determine the full set of coefficients for the completely general 4-loop gauge and 3-loop Yukawa β-functions for the most general renormalizable four-dimensional theories. Using a complete parametrization of the β-functions, we compare the general form to the specific β-functions of known theories to constrain the unknown coefficients. The Weyl consistency conditions provide additional constraints, completing the determination. [ABSTRACT FROM AUTHOR]

In this paper we consider the next-to-next-to-leading order total cross section of Higgs boson pair production in the large top quark mass limit and compute four expansion terms in 1/ m t 2 . To this end, we analytically compute the real-virtual and double-real contributions to the total cross section and combine them with the existing virtual contribution. Good convergence is observed below the top quark threshold, which makes our results a valuable input for approximation methods which aim for next-to-next-to-leading order corrections over the whole kinematic range. We present details on various steps of our calculation; in particular, we provide results for three- and four-particle phase-space master integrals and describe in detail the evaluation of the collinear counterterms. [ABSTRACT FROM AUTHOR]

The widespread use and development of inertia friction welding is currently restricted by an incomplete understanding of the deformation mechanisms and microstructure evolution during the process. Understanding phase transformations and lattice strains during inertia friction welding is essential for the development of robust numerical models capable of determining optimized process parameters and reducing the requirement for costly experimental trials. A unique compact rig has been designed and used in‐situ with a high‐speed synchrotron X‐ray diffraction instrument to investigate the microstructure evolution during inertia friction welding of a high‐carbon steel (BS1407). At the contact interface, the transformation from ferrite to austenite was captured in great detail, allowing for analysis of the phase fractions during the process. Measurement of the thermal response of the weld reveals that the transformation to austenite occurs 230 °C below the equilibrium start temperature of 725 °C. It is concluded that the localization of large strains around the contact interface produced as the specimens deform assists this non‐equilibrium phase transformation. [ABSTRACT FROM AUTHOR]

We calculate the two-loop QCD corrections to gg → ZZ involving a closed top-quark loop. We present a new method to systematically construct linear combinations of Feynman integrals with a convergent parametric representation, where we also allow for irreducible numerators, higher powers of propagators, dimensionally shifted integrals, and subsector integrals. The amplitude is expressed in terms of such finite integrals by employing syzygies derived with linear algebra and finite field techniques. Evaluating the amplitude using numerical integration, we find agreement with previous expansions in asymptotic limits and provide ab initio results also for intermediate partonic energies and non-central scattering at higher energies. [ABSTRACT FROM AUTHOR]

We present results for the two-loop helicity amplitudes entering the NLO QCD corrections to the production of a Higgs boson in association with a Z -boson in gluon fusion. The two-loop integrals, involving massive top quarks, are calculated numerically. Results for the interference of the finite part of the two-loop amplitudes with the Born amplitude are shown as a function of the two kinematic invariants on which the amplitudes depend. [ABSTRACT FROM AUTHOR]

We compute the next-to-leading order virtual corrections to the partonic cross-section of the process gg → ZH, in the high-energy and large-mt limits. We use Padé approximants to increase the radius of convergence of the high-energy expansion in m t 2 / s , m t 2 / t and m t 2 / u and show that precise results can be obtained down to energies which are fairly close to the top quark pair threshold. We present results both for the form factors and the next-to-leading order virtual cross-section. [ABSTRACT FROM AUTHOR]

Baddeleyite is a powerful chronometer of mafic magmatic and meteorite impact processes. Precise and accurate U--Pb ages can be determined from single grains by isotope dilution thermal ionization mass spectrometry (ID-TIMS), but this requires disaggregation of the host rock for grain isolation and dissolution. As a result, the technique is rarely applied to precious samples with limited availability (such as lunar, Martian, and asteroidal meteorites and returned samples) or samples containing small baddeleyite grains that cannot readily be isolated by conventional mineral separation techniques. Here, we use focused ion beam (FIB) techniques, utilizing both Xe+ plasma and Ga+ ion sources, to liberate baddeleyite subdomains directly, allowing their extraction for ID-TIMS dating. We have analysed the U--Pb isotope systematics of domains ranging between 200 and 10 µm in length and from 5 to ≤ 0:1 µg in mass. In total, six domains of Phalaborwa baddeleyite extracted using a Xe+ plasma FIB (pFIB) yield a weighted mean 207Pb/206Pb age of 2060:±2:5 Ma (0.12 %; all uncertainties 2σ), within uncertainty of reference values. The smallest extracted domain (ca. 10x15x10 µm) yields an internal 207Pb/206Pb age uncertainty of ±0:37%. Comparable control on cutting is achieved using a Ga+-source FIB instrument, though the slower speed of cutting limits potential application to larger grains. While the U--Pb data are between 0.5% and 13.6% discordant, the extent of discordance does not correlate with the ratio of material to ion-milled surface area, and results generate an accurate upper-intercept age in U--Pb concordia space of 2060:20±0:91 Ma (0.044%). Thus, we confirm the natural U--Pb variation and discordance within the Phalaborwa baddeleyite population observed with other geochronological techniques. Our results demonstrate the FIB-TIMS technique to be a powerful tool for highly accurate in situ 207Pb/206Pb (and potentially U--Pb in concordant materials) age analysis, allowing dating of a wide variety of targets and processes newly accessible to geochronology. [ABSTRACT FROM AUTHOR]

Johannes Hämmerli and Nicolas Greber receive the 2018 Paul Niggli Medal The Paul Niggli Medal is Switzerland's most prestigious award for young earth scientist who made outstanding contributions in the research fields of mineralogy, geochemistry, petrology, resource geology or solid-earth geophysics. In his PhD Nicolas found that Mo isotope ratios in molybdenite are significantly different from their host rocks, observing high temperature Mo isotope fractionation for the first time. [Extracted from the article]

The composite Meghri–Ordubad pluton (MOP) is located in the southernmost Lesser Caucasus and crops out over ∼1000 km2 in southern Armenia and Nakhitchevan. It is characterized by nested intrusions incrementally emplaced over ∼30 Myr from the Middle Eocene to Early Miocene, coeval with the closure of the Neotethyan Ocean and the regional Arabia-Eurasia continental collision. We recognize three compositionally distinct intrusive series in the MOP: a medium- to high-K calc-alkaline series 1 dominated by gabbro, quartz diorite and tonalite, a shoshonitic to high-K calc-alkaline series 2 including gabbro, monzogabbro, monzodiorite, monzonite and syenite, and a high-K calc-alkaline adakitic series 3 characterized by the emplacement of lamprophyre dikes followed by porphyritic granodioritic intrusions and dikes. Amphibole thermobarometry together with detailed petrography, mineral chemistry and experimental mineral stability P–T diagrams indicate a polybaric crystallization history and magma emplacement at mid- to upper crustal levels (0·1–0·3 GPa). Mineral textures and compositions reveal open-system magmatic processes such as mafic magma replenishment and reactivation of crystal mushes prior to transport towards shallower crustal levels in the MOP. The evolution of magma chemistry (calc-alkaline vs shoshonitic) and mineral assemblages (amphibole-bearing vs amphibole-free) indicate fluctuation in primary melt alkali and water contents over time. Such chemical evolution is ascribed to a decrease in the degree of partial melting of a chemically heterogeneous, but isotopically homogeneous, mantle source. Overall, the MOP is characterized by the successive emplacement of hydrous magma batches in the mid- to upper crust and petrological processes that were dominated by fractional crystallization (± crustal assimilation) upon cooling and, or, decompression (± degassing). We propose a new temporal and spatial petrogenetic model for the MOP, encompassing three long-lived, chemically distinct magmatic series incrementally assembled over 30 Myr within a pre-, syn- and post-collisional geodynamic setting. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we describe an in situ non-destructive technique to identify areas within zircon crystals that have experienced fluid exchange. We show that Raman spectroscopy combined with electron microprobe trace-element analysis can be used to pinpoint areas in altered, complexly zoned, and metamict zircon that record the original magmatic compositions. These techniques are developed on a suite of Paleoproterozoic zircon crystals from the Scourie dike swarm in the Archean gneiss terrane of NW Scotland that are known to be anomalously low in δ18O. We show that zircons from the Scourie dikes record extremely low-δ18O isotopic compositions down to approximately -3‰, which reflect their magmatic values. Zircon populations from the dikes have a range in δ18O from low values (<0‰) up to ~5‰ with no obvious relationship between oxygen isotopic composition and cathodoluminescence. Raman spectra from the zircons show evidence for fluid interaction in some areas of the grains because of partial recrystallization and atypical radiation damage properties. Electron microprobe analysis in the same areas documents high (>1000 ppm) U concentrations and high (>1000 ppm) abundances of non-formula Ca. When the combined Raman and electron microprobe data are used to filter the oxygen isotopic data, the fluid altered areas of the grains show consistently higher δ18O values than the areas without evidence for fluid alteration. The low-δ18O values therefore reflect the original magmatic composition of the grains and indicate that the Scourie dike magmas were low in 18O. We suggest that these non-destructive techniques should be used prior to SIMS analysis of complex zircons to target the least disturbed areas of the grains. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journalism Research is the property of Sur le journalisme, About journalism, Sobre jornalismo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cruise ships are among the most visible postmodern tourism products, and cruise tourists are the antithesis of cultural tourists. Within the physical cocoon of the ship, a social and cultural cocoon is constructed by the cruise line, sheltering the temporary inhabitants of the ship from the realities of the ports visited. Despite the portrayal of a cruise as an "exotic" holiday, onboard the ship, cruise ships construct a representation of western culture, particularly with the assistance of onboard musical performances. This article considers the performance of the showband, a central ensemble to the musical experience of a cruise vacation. It is the result of an extended period of participant-observation on cruise ships and interviews with showband musicians. The contribution of the showband is found to be central to the construction of a western and cosmopolitan music culture within a deterritorialised and mobile geography. By performance mode and genre, appearance, repertoire, and nationality, the showband constructs a façade of music culture; however, the reality behind the façade is quite different. If the ship may be considered an empty vessel into which culture is poured, it is the music of ensembles such as the showband that creates and defnes this culture. [ABSTRACT FROM AUTHOR]

The pH drop in the hindgut of the horse is caused by lactic acid-producing bacteria which are abundant when a horse's feeding regime is excessively carbohydrate rich. This drop in pH below six causes hindgut acidosis and may lead to laminitis. Lactic acid-producing bacteria Streptococcus equinus and Mitsuokella jalaludinii have been found to produce high amounts of L-lactate and D-lactate, respectively. Early detection of increased levels of these bacteria could allow the horse owner to tailor the horse's diet to avoid hindgut acidosis and subsequent laminitis. Therefore, 16s ribosomal ribonucleic acid (rRNA) sequences were identified and modified to obtain target single stranded deoxyribonucleic acid (DNA) from these bacteria. Complementary single stranded DNAs were designed from the modified target sequences to form capture probes. Binding between capture probe and target single stranded deoxyribonucleic acid (ssDNA) in solution has been studied by gel electrophoresis. Among pairs of different capture probes and target single stranded DNA, hybridization of Streptococcus equinus capture probe 1 (SECP1) and Streptococcus equinus target 1 (SET1) was portrayed as gel electrophoresis. Adsorptive stripping voltammetry was utilized to study the binding of thiol modified SECP1 over gold on glass substrates and these studies showed a consistent binding signal of thiol modified SECP1 and their hybridization with SET1 over the gold working electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were employed to examine the binding of thiol modified SECP1 on the gold working electrode and hybridization of thiol modified SECP1 with the target single stranded DNA. Both demonstrated the gold working electrode surface was modified with a capture probe layer and hybridization of the thiol bound ssDNA probe with target DNA was indicated. Therefore, the proposed electrochemical biosensor has the potential to be used for the detection of the non-synthetic bacterial DNA target responsible for equine hindgut acidosis. [ABSTRACT FROM AUTHOR]

The tensions between the STEM fields and the Humanities are artificial and might be the result of nothing but political and financial competition. In essence, all scholars explore their topics in a critical fashion, relying on the principles of verification and falsification. Most important proves to be the notion of the laboratory, the storehouse of experiences, ideas, imagination, experiments. For that reason, here the metaphor of the Amazon rainforest is used to illustrate where the common denominators for scientists and scholars rest. Without that vast field of experiences from the past the future cannot be built. The focus here is based on the human condition and its reliance on ethical ideals as already developed by Aristotle. In fact, neither science nor humanities-based research are possible without ethics. Moreover, as illustrated by the case of one of the stories by Heinrich Kaufringer (ca. 1400), human conditions have always been precarious, contingent, puzzling, and fragile, especially if ethics do not inform the individual's actions. Pre-modern literature is here identified as an 'Amazon rainforest' that only waits to be explored for future needs. [ABSTRACT FROM AUTHOR]

Small bowel obstruction (SBO) is one of the most common causes for an acute surgical admission. Most of the time SBO is a result of common causes such as postoperative adhesions. However, rare and unusual causes of SBO do exist which can be challenging for surgeons. We report a first documented case of SBO caused by a remnant of the vas deferens in a 24-yearold patient with a history of gastroschisis and left orchidectomy. Clinical presentation, investigations, imaging and management of this case are described. To summarise, clinicians should keep an open mind in dealing with patients with intestinal obstruction due to the rare and atypical causes. [ABSTRACT FROM AUTHOR]

An important ingredient for the calculation of Higgs boson properties in the infinite top quark mass limit is the knowledge of the effective coupling between the Higgs bosons and gluons, i.e. the Wilson coefficients CH and CHH for one and two Higgs bosons, respectively. In this work we calculate for the first time CHH to four loops in a direct, diagrammatic way, discussing in detail all issues arising due to the renormalization of operator products. Furthermore, we also calculate the Wilson coefficient CH for the coupling of a single Higgs boson to gluons as well as all four loop decoupling relations in QCD with general SU(Nc) colour factors. The latter are related to CH and CHH via low-energy theorems, which are used to obtain five-loop results for the Wilson coefficients. [ABSTRACT FROM AUTHOR]

Earlier work had indicated that enzyme-mediated hydrolysis of xylooligomer-rich water-soluble streams (derived from steam pre-treated wheat straw) resulted in the effective production of xylose which was subsequently used to produce bio-glycol. In the work reported here, both the thermostability and recyclability of xylanases were significantly improved by covalent immobilizing the enzymes onto alginate beads. The immobilized xylanases showed a lower hydrolytic potential (~55% xylooligomer conversion) compared to the commercial xylanase cocktail HTec3 (~90% xylooligomer conversion) when used at the same protein loading concentration. This was likely due to the less efficient immobilization of key higher molecular weight enzymes (>75 kDa), such as β-xylosidases. However, enzyme immobilization could be improved by lowering the glutaraldehyde loading used to activate the alginate beads, resulting in improved hydrolysis efficacy (~65% xylooligomer conversion). Enzyme immobilization improved enzyme thermostability (endoxylanase and β-xylosidase activities were improved by 80% and 40%, respectively, after 24 h hydrolysis) and this allowed the immobilized enzymes to be reused/recycled for multiple rounds of hydrolysis (up to five times) without any significant reduction in their hydrolytic potential. [ABSTRACT FROM AUTHOR]