bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ALLEGED MURDER OF HRETHRIC IN BEOWULF
Authors: OSBORN MARIJANE
Published: November 2019

A scenario well known to Beowulf scholars alleges that after Beowulf has slain the monsters and gone home, Hrothulf, nephew of the Danish king Hrothgar, will murder prince Hrethric to gain the throne when the old king dies. This story, that many Anglo-Saxonists assume is integral to the ancient legend of these kings, is a modern misreading of the poet's allusions to events associated with the Scylding dynasty — a legendary history that the poet arguably takes care to follow. The present essay, in two parts, first shows how the idea of Hrothulf's treachery arose and became canonical under the influence of prestigious English and American scholars, then finds fault with this idea, refuting its “proof” from Saxo Grammaticus and showing how some Anglo-Saxonists have doubted that Beowulf supports an interpretation making Hrothulf a murderer. But when the poet's allusions to future treachery are ambiguous, at least for modern readers, in order to exonerate Hrothulf fully one must go to traditions about the Scylding dynasty outside the poem. Scandinavian regnal lists (including one that Saxo himself incorporates) consistently contradict the event the Saxo passage has been used to prove, as they agree on a sequence of Scylding rulers with names corresponding to those of persons in Beowulf. Attention to this traditional sequence exposes Hrothulf's murder of Hrethric as a logical impossibility. Moreover, the early medieval method of selecting rulers suggests that neither did Hrothulf usurp the throne of Denmark. In sum, careful scrutiny of the best Scandinavian evidence and rejection of the worst reveals Beowulf's “treacherous Hrothulf” to be a scholarly fantasy.
Efficacy of dicamba and glyphosate as influenced by carrier water pH and hardness
Authors: Devkota Pratap , Johnson William G.
Published: November 2019

Herbicide carrier water hardness and pH can be variable depending on the source and geographic location. Herbicide efficacy can be affected by the pH and hardness of water used for spray solution. Field and greenhouse studies were conducted to evaluate the effect of carrier water pH and hardness on premixed dicamba and glyphosate efficacy. Treatments were combinations of water pH at 4, 6.5, or 9; and water hardness at 0 (deionized water), 400, or 800 mg L−1 of CaCO3 equivalent. In the field study, dicamba and glyphosate were applied at 0.55 and 1.11 kg ae ha−1, respectively, and half of these rates were applied in the greenhouse study. There was no interaction between carrier water pH and hardness on dicamba and glyphosate efficacy; however, the main effects of carrier water pH and hardness were significant. Herbicide efficacy was reduced with carrier water at pH 9 compared with pH 4. In the field study, common lambsquarters, common ragweed, horseweed, or Palmer amaranth control was improved 6% or more at carrier water at pH 4 compared with pH 9. Similar results were observed with water pH for giant ragweed, Palmer amaranth, or pitted morningglory control in the greenhouse study. Carrier water hardness at 400 or 800 mg L−1 reduced common ragweed, giant ragweed, or horseweed control compared with 0 mg L−1. Similarly, common lambsquarters, Palmer amaranth, or pitted morningglory control was reduced at least 10% with carrier water hardness at 800 mg L−1 compared with 0 mg L−1. These results indicate carrier water at acidic pH and of no hardness is critical for dicamba and glyphosate application, and spray solution needs to be amended appropriately for an optimum efficacy.
A Cock in the Henhouse
Authors: Barelds Dick P. H. , Dijkstra Pieternel , van Brummen-Girigori Odette
Published: November 2019

Abstract. The present study’s primary aim was to examine the effect of an imbalanced sex ratio on the Dark Triad traits, three types of jealousy, and their relations. For this purpose, data were collected in the Netherlands ( n = 297) and Curaçao ( n = 199). Curaçao is a constituent part of the Netherlands, but has, contrary to the Netherlands, a highly imbalanced sex ratio. We expected the Dark Triad traits to be positively related to anxious and preventive jealousy, but not to reactive jealousy (Hypothesis 1), and, in addition, these relations to be more pronounced in Curaçao than in the Netherlands (Hypothesis 2). Furthermore, it was expected that Curaçaoan men would score higher on the Dark Triad traits than Dutch men (Hypothesis 3), and that Curaçaoan men and women would, overall, report higher levels of jealousy than Dutch men and women (Hypothesis 4). Results largely supported Hypotheses 1, 2, and 4, but not Hypothesis 3. Results are discussed in relation to the role of sex ratio and the cultural beliefs that may accompany it. The current study’s findings may provide new insights into the role of the Dark Triad traits in mating psychology.
Intense Self-Regulatory Effort Increases Need for Conservation and	Reduces Attractiveness of Energy-Requiring Rewards
Authors: Giacomantonio Mauro , Jordan Jennifer , Fennis Bob M.
Published: November 2019

Abstract. Exertion of self-control produces distinct motivational consequences: the motivation to conserve energy and the motivation to seek rewards. We propose that heightened conservation inhibits reward-seeking, but only when the pursuit of the reward entails substantial energy expenditure. In two studies, we manipulated self-regulatory effort and then had participants engage in an additional task that was either easy or difficult. In Study 1, we found that self-regulatory effort tended to heighten reward-sensitivity but only when the subsequent task was easy. In Study 2, we measured pupil dilation to assess reward sensitivity while participants viewed images of rewarding stimuli. When the need to conserve was intense, we observed reduced pupil dilation for rewards that were energy-requiring but not for those that were energy-giving.
Sensor Response Estimate and Cross Calibration of Paleomagnetic Measurements on Pass‐Through Superconducting Rock Magnetometers
Authors: Xuan Chuang , Oda Hirokuni
Published: November 2019

Pass‐through superconducting rock magnetometers (SRMs) enable rapid and precise remanence measurement of continuous samples and are essential for paleomagnetic studies. Due to convolution effect of the SRM sensor response, pass‐through measurements need to be deconvolved to restore accurate and high‐resolution signal. A key step toward successful deconvolution is a reliable estimate of the SRM sensor response. Here, we present new tool URESPONSE for accurate SRM sensor response estimate based on measurements of a well‐calibrated magnetic point source. URESONSE allows sensor response to be estimated for continuous samples with different cross‐section geometry. We estimate sensor responses for an old liquid helium‐cooled SRM (SRM‐old) and a new liquid helium‐free SRM (SRM‐new) at the University of Southampton and compare remanence measurement of a u‐channel on both SRMs before and after deconvolution. For each SRM, sensor response estimates based on data collected using different magnetic point source samples and/or measurement procedures generally yield small differences (std. <~1%), while sensor response estimates for continuous samples with different cross‐section geometry often show larger differences (std. up to ~2%). Compared with SRM‐old, SRM‐new has smaller cross‐axis responses, less negative zones, and significantly broader main axis responses. We demonstrate that normalization of data using a nine‐element “effective length” matrix calculated from sensor response estimate is necessary to minimize differences in measurements on two SRMs. Deconvolution of measurements on two SRMs using accurate sensor response estimates yields highly consistent and high‐resolution results, while deconvolution using inaccurate sensor response data can lead to significant differences especially for data from SRM‐old that has large cross‐axis responses.
Osteocyte dysfunction promotes osteoarthritis through MMP13-dependent suppression of subchondral bone homeostasis
Authors: Mazur Courtney M. , Woo Jonathon J. , Yee Cristal S. , Fields Aaron J. , Acevedo Claire , Bailey Karsyn N. , Kaya Serra , Fowler Tristan W. , Lotz Jeffrey C. , Dang Alexis , Kuo Alfred C. , Vail Thomas P. , Alliston Tamara
Published: November 2019

Osteoarthritis (OA), long considered a primary disorder of articular cartilage, is commonly associated with subchondral bone sclerosis. However, the cellular mechanisms responsible for changes to subchondral bone in OA, and the extent to which these changes are drivers of or a secondary reaction to cartilage degeneration, remain unclear. In knee joints from human patients with end-stage OA, we found evidence of profound defects in osteocyte function. Suppression of osteocyte perilacunar/canalicular remodeling (PLR) was most severe in the medial compartment of OA subchondral bone, with lower protease expression, diminished canalicular networks, and disorganized and hypermineralized extracellular matrix. As a step toward evaluating the causality of PLR suppression in OA, we ablated the PLR enzyme MMP13 in osteocytes while leaving chondrocytic MMP13 intact, using Cre recombinase driven by the 9.6-kb DMP1 promoter. Not only did osteocytic MMP13 deficiency suppress PLR in cortical and subchondral bone, but it also compromised cartilage. Even in the absence of injury, osteocytic MMP13 deficiency was sufficient to reduce cartilage proteoglycan content, change chondrocyte production of collagen II, aggrecan, and MMP13, and increase the incidence of cartilage lesions, consistent with early OA. Thus, in humans and mice, defects in PLR coincide with cartilage defects. Osteocyte-derived MMP13 emerges as a critical regulator of cartilage homeostasis, likely via its effects on PLR. Together, these findings implicate osteocytes in bone-cartilage crosstalk in the joint and suggest a causal role for suppressed perilacunar/canalicular remodeling in osteoarthritis.
A tool for functional brain imaging with lifespan compliance
Authors: Hill Ryan M. , Boto Elena , Holmes Niall , Hartley Caroline , Seedat Zelekha A. , Leggett James , Roberts Gillian , Shah Vishal , Tierney Tim M. , Woolrich Mark W. , Stagg Charlotte J. , Barnes Gareth R. , Bowtell Richard , Slater Rebeccah , Brookes Matthew J.
Published: November 2019

The human brain undergoes significant functional and structural changes in the first decades of life, as the foundations for human cognition are laid down. However, non-invasive imaging techniques to investigate brain function throughout neurodevelopment are limited due to growth in head-size with age and substantial head movement in young participants. Experimental designs to probe brain function are also limited by the unnatural environment typical brain imaging systems impose. However, developments in quantum technology allowed fabrication of a new generation of wearable magnetoencephalography (MEG) technology with the potential to revolutionise electrophysiological measures of brain activity. Here we demonstrate a lifespan-compliant MEG system, showing recordings of high fidelity data in toddlers, young children, teenagers and adults. We show how this system can support new types of experimental paradigm involving naturalistic learning. This work reveals a new approach to functional imaging, providing a robust platform for investigation of neurodevelopment in health and disease.
Metabolic dysregulation in vitamin E and carnitine shuttle energy mechanisms associate with human frailty
Authors: Rattray Nicholas J. W. , Trivedi Drupad K. , Xu Yun , Chandola Tarani , Johnson Caroline H. , Marshall Alan D. , Mekli Krisztina , Rattray Zahra , Tampubolon Gindo , Vanhoutte Bram , White Iain R. , Wu Frederick C. W. , Pendleton Neil , Nazroo James , Goodacre Royston
Published: November 2019

Global ageing poses a substantial economic burden on health and social care costs. Enabling a greater proportion of older people to stay healthy for longer is key to the future sustainability of health, social and economic policy. Frailty and associated decrease in resilience plays a central role in poor health in later life. In this study, we present a population level assessment of the metabolic phenotype associated with frailty. Analysis of serum from 1191 older individuals (aged between 56 and 84 years old) and subsequent longitudinal validation (on 786 subjects) was carried out using liquid and gas chromatography-mass spectrometry metabolomics and stratified across a frailty index designed to quantitatively summarize vulnerability. Through multivariate regression and network modelling and mROC modeling we identified 12 significant metabolites (including three tocotrienols and six carnitines) that differentiate frail and non-frail phenotypes. Our study provides evidence that the dysregulation of carnitine shuttle and vitamin E pathways play a role in the risk of frailty.
Noble gases confirm plume-related mantle degassing beneath Southern Africa
Authors: Gilfillan S. M. V. , Györe D. , Flude S. , Johnson G. , Bond C. E. , Hicks N. , Lister R. , Jones D. G. , Kremer Y. , Haszeldine R. S. , Stuart F. M.
Published: November 2019

Southern Africa is characterised by unusually elevated topography and abnormal heat flow. This can be explained by thermal perturbation of the mantle, but the origin of this is unclear. Geophysics has not detected a thermal anomaly in the upper mantle and there is no geochemical evidence of an asthenosphere mantle contribution to the Cenozoic volcanic record of the region. Here we show that natural CO2 seeps along the Ntlakwe-Bongwan fault within KwaZulu-Natal, South Africa, have C-He isotope systematics that support an origin from degassing mantle melts. Neon isotopes indicate that the melts originate from a deep mantle source that is similar to the mantle plume beneath Réunion, rather than the convecting upper mantle or sub-continental lithosphere. This confirms the existence of the Quathlamba mantle plume and importantly provides the first evidence in support of upwelling deep mantle beneath Southern Africa, helping to explain the regions elevation and abnormal heat flow.
Restructuring of the ‘Macaronesia’ biogeographic unit: A marine multi-taxon biogeographical approach
Authors: Freitas Rui , Romeiras Maria , Silva Luís , Cordeiro Ricardo , Madeira Patrícia , González José Antonio , Wirtz Peter , Falcón Jesús M. , Brito Alberto , Floeter Sergio R. , Afonso Pedro , Porteiro Filipe , Viera-Rodríguez María Ascensión , Neto Ana Isabel , Haroun Ricardo , Farminhão João N. M. , Rebelo Ana Cristina , Baptista Lara , Melo Carlos S. , Martínez Alejandro , Núñez Jorge , Berning Björn , Johnson Markes E. , Ávila Sérgio P.
Published: November 2019

The Azores, Madeira, Selvagens, Canary Islands and Cabo Verde are commonly united under the term “Macaronesia”. This study investigates the coherency and validity of Macaronesia as a biogeographic unit using six marine groups with very different dispersal abilities: coastal fishes, echinoderms, gastropod molluscs, brachyuran decapod crustaceans, polychaete annelids, and macroalgae. We found no support for the current concept of Macaronesia as a coherent marine biogeographic unit. All marine groups studied suggest the exclusion of Cabo Verde from the remaining Macaronesian archipelagos and thus, Cabo Verde should be given the status of a biogeographic subprovince within the West African Transition province. We propose to redefine the Lusitanian biogeographical province, in which we include four ecoregions: the South European Atlantic Shelf, the Saharan Upwelling, the Azores, and a new ecoregion herein named Webbnesia, which comprises the archipelagos of Madeira, Selvagens and the Canary Islands.
Author Correction: When the statistical MMN meets the physical MMN
Authors: Tsogli Vera , Jentschke Sebastian , Daikoku Tatsuya , Koelsch Stefan
Published: November 2019

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Human oocytes and zygotes are ready for ultra-fast vitrification after 2 minutes of exposure to standard CPA solutions
Authors: Gallardo Miguel , Saenz Jaime , Risco Ramon
Published: November 2019

Vitrification of human oocytes and embryos in different stages of development is a key element of daily clinical practice of in vitro fertilization treatments. Despite the cooling and warming of the cells is ultra-fast, the procedure as a whole is time consuming. Most of the duration is employed in a long (8–15 minutes), gradual or direct exposure to a non-vitrifying cryoprotectant solution, which is followed by a short exposure to a more concentrated vitrifying solution. A reduction in the duration of the protocols is desirable to improve the workflow in the IVF setting and reduce the time of exposure to suboptimal temperature and osmolarity, as well as potentially toxic cryoprotectants. In this work it is shown that this reduction is feasible. In silico (MatLab program using two-parameter permeability model) and in vitro observations of the oocytes’ osmotic behaviour indicate that the dehydration upon exposure to standard cryoprotectant solutions occurs very fast: the point of minimum volume of the shrink-swell curve is reached within 60 seconds. At that point, intracellular water ejection is complete, which coupled with the permeation of low molecular weight cryoprotectants results in similar intracellular and extracellular solute concentrations. This shows that prolonging the exposure to the cryoprotectant solutions does not improve the cytosolic glass forming tendency and could be avoided. To test this finding, human oocytes and zygotes that were donated for research were subjected to a shortened, dehydration-based protocol, consisting of two consecutive exposures of one-minute to two standard cryoprotectant solutions, containing ethylene glycol, dimethyl sulfoxide and sucrose. At the end of this two-minute dehydration protocol, the critical intracellular solute concentration necessary for successful vitrification was attained, confirmed by the post-warming survival and ability to resume cytokinesis of the cells. Further studies of the developmental competency of oocytes and embryos would be necessary to determine the suitability of this specific dehydration protocol for clinical practice, but based on our results, short times of exposure to increasingly hypertonic solutions could be a more time-efficient strategy to prepare human oocytes and embryos for vitrification.
Synthesis of new isoquinoline-base-oxadiazole derivatives as potent inhibitors of thymidine phosphorylase and molecular docking study
Authors: Zaman Khalid , Rahim Fazal , Taha Muhammad , Wadood Abdul , Shah Syed Adnan Ali , Ahmed Qamar Uddin , Zakaria Zainul Amiruddin
Published: November 2019

Here in this study regarding the over expression of TP, which causes some physical, mental and socio problems like psoriasis, chronic inflammatory disease, tumor angiogenesis and rheumatoid arthritis etc. By this consideration, the inhibition of this enzyme is vital to secure life from serious threats. In connection with this, we have synthesized twenty derivatives of isoquinoline bearing oxadiazole (1–20), characterized through different spectroscopic techniques such as HREI-MS, 1H- NMR and 13C-NMR and evaluated for thymidine phosphorylase inhibition. All analogues showed outstanding inhibitory potential ranging in between 1.10 ± 0.05 to 54.60 ± 1.50 µM. 7-Deazaxanthine (IC50 = 38.68 ± 1.12 µM) was used as a positive control. Through limited structure activity relationships study, it has been observed that the difference in inhibitory activities of screened analogs are mainly affected by different substitutions on phenyl ring. The effective binding interactions of the most active analogs were confirmed through docking study.
Formation of a photocatalytic WO3 surface layer on electrodeposited Al–W alloy coatings by selective dissolution and heat treatment
Authors: Higashino Shota , Miyake Masao , Ikenoue Takumi , Hirato Tetsuji
Published: November 2019

In this study, we explored the feasibility of WO3 surface layer formation on electrodeposited Al–W alloy coatings by selective dissolution and heat treatment, with the aim of providing corrosion-resistant Al–W alloy coatings with photocatalytic self-cleaning properties under visible light illumination. The selective dissolution of Al and oxidation of residual W was carried out by immersing Al–W alloy films in an aqueous solution of nitric acid. A nanostructured H2WO4·H2O surface layer was formed on the alloy film by this process. The H2WO4·H2O layer was dehydrated to WO3 by heat treatment, yielding a multilayered WO3/Al–W alloy film with an approximately 300 nm thick WO3 layer. The WO3/Al–W alloy film exhibited photocatalytic self-cleaning, as demonstrated by the photodegradation of stearic acid and methylene blue. We also confirmed that selective dissolution and heat treatment did not significantly diminish the corrosion resistance of the Al–W alloy films.
Road related pollutants induced DNA damage in dragonfly nymphs (Odonata, Anisoptera) living in highway sedimentation ponds
Authors: Meland Sondre , Gomes Tânia , Petersen Karina , Håll Johnny , Lund Espen , Kringstad Alfhild , Grung Merete
Published: November 2019

Nowadays, stormwater sedimentation ponds are popular in stormwater management because of their ability to mitigate flooding and treat polluted runoff from e.g. roads. In addition, they may provide other ecosystem services such as biodiversity. These man-made habitats will inevitably be polluted and the organisms living therein may be negatively affected by the chemical cocktail present in both the water and sediment compartments. The present study explored DNA damage in dragonfly nymphs (Odonata, Anisoptera) living in highway sedimentation ponds in comparison with natural ponds. The concentrations of Polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs and metals were also determined in sediment samples from the different ponds. The results showed that DNA damage was significantly higher in dragonfly nymphs living in sedimentation ponds compared to nymphs living in natural ponds. DNA damage was also highly and significantly correlated with the pollution levels in the sediment, i.e., PAH and Zinc. Finally, we report the concentrations of various alkylated PAHs which appeared to be very dominant in the sedimentation ponds. Our results show that there may be a conflict between the sedimentation ponds’ primary function of protecting natural water bodies from polluted runoff and their secondary function as habitats for organisms. Overall, we suggest that this must be considered when planning and designing stormwater measures.
Gamma Attenuation Coefficients of Nano Cadmium Oxide/High density Polyethylene Composites
Authors: El-Khatib Ahmed M. , Abbas Mahmoud I. , Elzaher Mohamed Abd , Badawi Mohamed S. , Alabsy Mahmoud T. , Alharshan Gharam A. , Aloraini Dalal A.
Published: November 2019

In the present work, high density polyethylene (HDPE) matrix mixed with micro-sized and nano-sized Cadmium oxide (CdO) particles of different concentrations were prepared by compression molding technique. The aim of the study is to investigate the effect of particle size and weight percentage of CdO particles on the gamma radiation shielding ability of CdO/HDPE composites. The mass attenuation coefficients of pure HDPE, micro-CdO/HDPE and nano-CdO/HDPE composites were evaluated at photon energies ranging from 59.53 keV to 1408.01 keV using standard radioactive point sources [241Am, 133Ba, 137Cs, 60Co and 152Eu]. Adding micro and nano CdO particles to the HDPE matrix clearly increases the mass attenuation coefficients of the composites and the improvement is more significant at low γ-ray energies. The effect of particle size of CdO filler has an important role on the shielding ability of the composite. The experimental results reveal that, the composites filled with nano-CdO have better γ-radiation shielding ability compared to that filled with micro-CdO at the same weight fraction. A relative increase rate of about 16% is obtained with nano-CdO content of 40 wt% at 59.53 keV, which attributed to the higher probability of interaction between γ-rays and nanoparticles. From this study, it can be concluded that nano-CdO has a good performance shielding characteristic than micro-CdO in HDPE based radiation shielding material.
Exciton Absorption and Luminescence in i-Motif DNA
Authors: Reveguk Zakhar V. , Khoroshilov Evgeny V. , Sharkov Andrey. V. , Pomogaev Vladimir A. , Buglak Andrey A. , Tarnovsky Alexander N. , Kononov Alexei I.
Published: November 2019

We have studied the excited-state dynamics for the i-motif form of cytosine chains (dC)10, using the ultrafast fluorescence up-conversion technique. We have also calculated vertical electronic transition energies and determined the nature of the corresponding excited states in a model tetramer i-motif structure. Quantum chemical calculations of the excitation spectrum of a tetramer i-motif structure predict a significant (0.3 eV) red shift of the lowest-energy transition in the i-motif form relative to its absorption maximum, which agrees with the experimental absorption spectrum. The lowest excitonic state in i-(dC)10 is responsible for a 2 ps red-shifted emission at 370 nm observed in the decay-associated spectra obtained on the femtosecond time-scale. This delocalized (excitonic) excited state is likely a precursor to a long-lived excimer state observed in previous studies. Another fast 310 fs component at 330 nm is assigned to a monomer-like locally excited state. Both emissive states form within less than the available time resolution of the instrument (100 fs). This work contributes to the understanding of excited-state dynamics of DNA within the first few picoseconds, which is the most interesting time range with respect to unraveling the photodamage mechanism, including the formation of the most dangerous DNA lesions such as cyclobutane pyrimidine dimers.
Cowpea (Vigna unguiculata (L.) Walp) for food security: an evaluation of end-user traits of improved varieties in Swaziland
Authors: Gondwe Therese Mwatitha , Alamu Emmanuel Oladeji , Mdziniso Phumzile , Maziya-Dixon Busie
Published: November 2019

Improved varieties have agronomic advantages over local varieties,but not much attention has been given to understand the nutritional content of the improved cowpea varieties released in Swaziland. This study investigated the physical and nutritional properties of improved cowpea varieties released in Swaziland. Five improved varieties (IT-04K-321-2, IT-97K-390-2, IT-18, IT-16, and IT-99K-494-6) and one local variety (Mtilane, as check) were analyzed for physical and chemical properties. The results showed that there were variations in seed weight as the values ranged between 12.5 and 18.5 g per 100 g seed weight. The protein content ranged from 25.38% to 27.56% with no significant difference (P < 0.05) between the improved varieties  and the local variety, ash content ranged between 3.47 and 6.84%, crude fiber was between 5.81 and 15.08%, and carbohydrate ranged from 45.64 to 57.12%.  Contents of calcium ranged from 9 to 36 mg/100 g and of iron from  2.0 to 2.4 mg/kg, with significant differences (P  < 0.05)  between the varieties with highest and the lowest values. Zinc content ranged from 7 mg/kg to 8 mg/kg, with no significant difference (P >0.05) among the varieties. The improved varieties have high seed weight, which is an essential factor that farmers consider when choosing a variety to adopt. In terms of addressing nutritional security, the crop is suitable for addressing protein-energy malnutrition and formulating blends for baby foods in Swaziland.
A Novel Semiconductor-Based Flow Cytometer with Enhanced Light-Scatter Sensitivity for the Analysis of Biological Nanoparticles
Authors: Brittain George C. , Chen Yong Q. , Martinez Edgar , Tang Vera A. , Renner Tyler M. , Langlois Marc-André , Gulnik Sergei
Published: November 2019

The CytoFLEX is a novel semiconductor-based flow cytometer that utilizes avalanche photodiodes, wavelength-division multiplexing, enhanced optics, and diode lasers to maximize light capture and minimize optical and electronic noise. Due to an increasing interest in the use of extracellular vesicles (EVs) as disease biomarkers, and the growing desire to use flow cytometry for the analyses of biological nanoparticles, we assessed the light-scatter sensitivity of the CytoFLEX for small-particle detection. We found that the CytoFLEX can fully resolve 70 nm polystyrene and 98.6 nm silica beads by violet side scatter (VSSC). We further analyzed the detection limit for biological nanoparticles, including viruses and EVs, and show that the CytoFLEX can detect viruses down to 81 nm and EVs at least as small as 65 nm. Moreover, we could immunophenotype EV surface antigens, including directly in blood and plasma, demonstrating the double labeling of platelet EVs with CD61 and CD9, as well as triple labeling with CD81 for an EV subpopulation in one donor. In order to assess the refractive indices (RIs) of the viruses and EVs, we devised a new method to inversely calculate the RIs using the intensity vs. size data together with Mie-theory scatter efficiencies scaled to reference-particle measurements. Each of the viruses tested had an equivalent RI, approximately 1.47 at 405 nm, which suggests that flow cytometry can be more broadly used to easily determine virus sizes. We also found that the RIs of EVs increase as the particle diameters decrease below 150 nm, increasing from 1.37 for 200 nm EVs up to 1.61 for 65 nm EVs, expanding the lower range of EVs that can be detected by light scatter. Overall, we demonstrate that the CytoFLEX has an unprecedented level of sensitivity compared to conventional flow cytometers. Accordingly, the CytoFLEX can be of great benefit to virology and EV research, and will help to expand the use of flow cytometry for minimally invasive liquid biopsies by allowing for the direct analysis of antigen expression on biological nanoparticles within patient samples, including blood, plasma, urine and bronchoalveolar lavages.
Satellite-based monitoring of groundwater depletion in California’s Central Valley
Authors: Vasco Donald W. , Farr Tom G. , Jeanne Pierre , Doughty Christine , Nico Peter
Published: November 2019

Range change data, obtained from Synthetic Aperture Radar satellites, form the basis for estimates of aquifer volume change in California’s Central Valley. The estimation algorithm incorporates a function penalizing changes far from known well locations, linking the aquifer volume changes to agricultural, industrial, and municipal pumping within the Tulare basin. We show that the range changes are compatible with the hypothesis that the source of aquifer volume changes are variations in effective pressure around documented wells. Specifically, inclusion of the well distance penalty does not degrade the fit to the observations, inversions with and without it both give variance reductions of 99.6%. The patterns of aquifer volume change vary significantly from the drought year, between October 2015 and October 2016, to a wet year in 2017, and into 2018, a year with near average rainfall. The 2.3 million acre-feet of estimated volume reduction, a lower bound on the amount of water extracted from the basin between October 2015 and 2016, agrees with independent estimates of 1.8 and 2.3 million acre-feet. The aquifer volume reduction is also compatible with a loss of 3.1 km3 (2.5 million acre-feet) in groundwater volume derived from Gravity Recovery and Climate Experiment (GRACE) satellite data.
Efficient Degradation of Poly(ethylene terephthalate) with Thermobifida fusca Cutinase Exhibiting Improved Catalytic Activity Generated using Mutagenesis and Additive-based Approaches
Authors: Furukawa Makoto , Kawakami Norifumi , Tomizawa Atsushi , Miyamoto Kenji
Published: November 2019

Cutinases are promising agents for poly(ethylene terephthalate) (PET) bio-recycling because of their ability to produce the PET monomer terephthalic acid with high efficiency under mild reaction conditions. In this study, we found that the low-crystallinity PET (lcPET) hydrolysis activity of thermostable cutinase from Thermobifida fusca (TfCut2), was increased by the addition of cationic surfactant that attracts enzymes near the lcPET film surface via electrostatic interactions. This approach was applicable to the mutant TfCut2 G62A/F209A, which was designed based on a sequence comparison with PETase from Ideonella sakaiensis. As a result, the degradation rate of the mutant in the presence of cationic surfactant increased to 31 ± 0.1 nmol min−1 cm−2, 12.7 times higher than that of wild-type TfCut2 in the absence of surfactant. The long-duration reaction showed that lcPET film (200 μm) was 97 ± 1.8% within 30 h, the fastest biodegradation rate of lcPET film thus far. We therefore believe that our approach would expand the possibility of enzyme utilization in industrial PET biodegradation.
Statistical Evolutionary Laws in Music Styles
Authors: Nakamura Eita , Kaneko Kunihiko
Published: November 2019

If a cultural feature is transmitted over generations and exposed to stochastic selection when spreading in a population, its evolution may be governed by statistical laws and be partly predictable, as in the case of genetic evolution. Music exhibits steady changes of styles over time, with new characteristics developing from traditions. Recent studies have found trends in the evolution of music styles, but little is known about their relations to the evolution theory. Here we analyze Western classical music data and find statistical evolutionary laws. For example, distributions of the frequencies of some rare musical events (e.g. dissonant intervals) exhibit steady increase in the mean and standard deviation as well as constancy of their ratio. We then study an evolutionary model where creators learn their data-generation models from past data and generate new data that will be socially selected by evaluators according to the content dissimilarity (novelty) and style conformity (typicality) with respect to the past data. The model reproduces the observed statistical laws and can make non-trivial predictions for the evolution of independent musical features. In addition, the same model with different parameterization can predict the evolution of Japanese enka music, which is developed in a different society and has a qualitatively different tendency of evolution. Our results suggest that the evolution of musical styles can partly be explained and predicted by the evolutionary model incorporating statistical learning, which can be important for other cultures and future music technologies.
Repeated long-distance dispersal and convergent evolution in hazel
Authors: Helmstetter Andrew J. , Buggs Richard J. A. , Lucas Stuart J.
Published: November 2019

Closely related species with a worldwide distribution provide an opportunity to understand evolutionary and biogeographic processes at a global scale. Hazel (Corylus) is an economically important genus of tree and shrub species found in temperate regions of Asia, North America and Europe. Here we use multiple nuclear and chloroplast loci to estimate a time-calibrated phylogenetic tree of the genus Corylus. We model the biogeographic history of this group and the evolutionary history of tree and shrub form. We estimate that multiple Corylus lineages dispersed long distances between Europe and Asia and colonised North America from Asia in multiple independent events. The geographic distribution of tree versus shrub form of species appears to be the result of 4–5 instances of convergent evolution in the past 25 million years. We find extensive discordance between our nuclear and chloroplast trees and potential evidence for chloroplast capture in species with overlapping ranges, suggestive of past introgression. The important crop species C. avellana is estimated to be closely related to C. maxima, C. heterophylla var. thunbergii and the Colurnae subsection. Our study provides a new phylogenetic hypothesis or Corylus and reveals how long-distance dispersal can shape the distribution of biodiversity in temperate plants.
Screening of suitable cationic dopants for solar absorber material CZTS/Se: A first principles study
Authors: Jyothirmai M. V. , Saini Himanshu , Park Noejung , Thapa Ranjit
Published: November 2019

The earth abundant and non-toxic solar absorber material kesterite Cu2ZnSn(S/Se)4 has been studied to achieve high power conversion efficiency beyond various limitations, such as secondary phases, antisite defects, band gap adjustment and microstructure. To alleviate these hurdles, we employed screening based approach to find suitable cationic dopant that can promote the current density and the theoretical maximum upper limit of the energy conversion efficiency (P(%)) of CZTS/Se solar devices. For this task, the hybrid functional (Heyd, Scuseria and Ernzerhof, HSE06) were used to study the electronic and optical properties of cation (Al, Sb, Ga, Ba) doped CZTS/Se. Our in-depth investigation reveals that the Sb atom is suitable dopant of CZTS/CZTSe and also it has comparable bulk modulus as of pure material. The optical absorption coefficient of Sb doped CZTS/Se is considerably larger than the pure materials because of easy formation of visible range exciton due to the presence of defect state below the Fermi level, which leads to an increase in the current density and P(%). Our results demonstrate that the lower formation energy, preferable energy gap and excellent optical absorption of the Sb doped CZTS/Se make it potential component for relatively high efficient solar cells.
Towards rational design and optimization of near-field enhancement and spectral tunability of hybrid core-shell plasmonic nanoprobes
Authors: Paria Debadrita , Zhang Chi , Barman Ishan
Published: November 2019

In biology, sensing is a major driver of discovery. A principal challenge is to create a palette of probes that offer near single-molecule sensitivity and simultaneously enable multiplexed sensing and imaging in the “tissue-transparent” near-infrared region. Surface-enhanced Raman scattering and metal-enhanced fluorescence have shown substantial promise in addressing this need. Here, we theorize a rational design and optimization strategy to generate nanostructured probes that combine distinct plasmonic materials sandwiching a dielectric layer in a multilayer core shell configuration. The lower energy resonance peak in this multi-resonant construct is found to be highly tunable from visible to the near-IR region. Such a configuration also allows substantially higher near-field enhancement, compared to a classical core-shell nanoparticle that possesses a single metallic shell, by exploiting the differential coupling between the two core-shell interfaces. Combining such structures in a dimer configuration, which remains largely unexplored at this time, offers significant opportunities not only for near-field enhancement but also for multiplexed sensing via the (otherwise unavailable) higher order resonance modes. Together, these theoretical calculations open the door for employing such hybrid multi-layered structures, which combine facile spectral tunability with ultrahigh sensitivity, for biomolecular sensing.
Action verb processing specifically modulates motor behaviour and sensorimotor neuronal oscillations
Authors: Klepp Anne , van Dijk Hanneke , Niccolai Valentina , Schnitzler Alfons , Biermann-Ruben Katja
Published: November 2019

Understanding action-related language recruits the brain’s motor system and can interact with motor behaviour. The current study shows MEG oscillatory patterns during verb-motor priming. Hand and foot verbs were followed by hand or foot responses, with faster reaction times for congruent conditions. In ROIs placed in the hand/arm and foot/leg portions of the sensorimotor cortex, this behavioural priming effect was accompanied by modulations in MEG oscillatory patterns preceding the responses. Power suppression in the alpha/beta frequency bands was reduced in congruent conditions in the body-part-specific ROIs. These results imply that the verb-motor priming effect may be a direct consequence of motor cortex contributions to action word processing.
Phonological network fluency identifies phonological restructuring through mental search
Authors: Neergaard Karl David , Luo Jin , Huang Chu-Ren
Published: November 2019

We investigated network principles underlying mental search through a novel phonological verbal fluency task. Post exclusion, 95 native-language Mandarin speakers produced as many items that differed by a single segment or lexical tone as possible within one minute. Their verbal productions were assessed according to several novel graded fluency measures, and network science measures that accounted for the structure, cohesion and interconnectedness of lexical items. A multivariate regression analysis of our participants’ language backgrounds included their mono- or multi-lingual status, English proficiency, and fluency in other Chinese languages/dialects. Higher English proficiency predicted lower error rates and greater interconnectedness, while higher fluency in other Chinese languages/dialects revealed lower successive similarity and lower network coherence. This inverse relationship between English and other Chinese languages/dialects provides evidence of the restructuring of the phonological mental lexicon.
Thermally and field-driven mobility of emergent magnetic charges in square artificial spin ice
Authors: Morley Sophie A. , Porro Jose Maria , Hrabec Aleš , Rosamond Mark C. , Venero Diego Alba , Linfield Edmund H. , Burnell Gavin , Im Mi-Young , Fischer Peter , Langridge Sean , Marrows Christopher H.
Published: November 2019

Designing and constructing model systems that embody the statistical mechanics of frustration is now possible using nanotechnology. We have arranged nanomagnets on a two-dimensional square lattice to form an artificial spin ice, and studied its fractional excitations, emergent magnetic monopoles, and how they respond to a driving field using X-ray magnetic microscopy. We observe a regime in which the monopole drift velocity is linear in field above a critical field for the onset of motion. The temperature dependence of the critical field can be described by introducing an interaction term into the Bean-Livingston model of field-assisted barrier hopping. By analogy with electrical charge drift motion, we define and measure a monopole mobility that is larger both for higher temperatures and stronger interactions between nanomagnets. The mobility in this linear regime is described by a creep model of zero-dimensional charges moving within a network of quasi-one-dimensional objects.
Synergistic Antibacterial Effects of Metallic Nanoparticle Combinations
Authors: Bankier C. , Matharu R. K. , Cheong Y. K. , Ren G. G. , Cloutman-Green E. , Ciric L.
Published: November 2019

Metallic nanoparticles have unique antimicrobial properties that make them suitable for use within medical and pharmaceutical devices to prevent the spread of infection in healthcare. The use of nanoparticles in healthcare is on the increase with silver being used in many devices. However, not all metallic nanoparticles can target and kill all disease-causing bacteria. To overcome this, a combination of several different metallic nanoparticles were used in this study to compare effects of multiple metallic nanoparticles when in combination than when used singly, as single elemental nanoparticles (SENPs), against two common hospital acquired pathogens (Staphylococcus aureus and Pseudomonas. aeruginosa). Flow cytometry LIVE/DEAD assay was used to determine rates of cell death within a bacterial population when exposed to the nanoparticles. Results were analysed using linear models to compare effectiveness of three different metallic nanoparticles, tungsten carbide (WC), silver (Ag) and copper (Cu), in combination and separately. Results show that when the nanoparticles are placed in combination (NPCs), antimicrobial effects significantly increase than when compared with SENPs (P < 0.01). This study demonstrates that certain metallic nanoparticles can be used in combination to improve the antimicrobial efficiency in destroying morphologically distinct pathogens within the healthcare and pharmaceutical industry.
Amelioration of Chromium VI Toxicity in Sorghum (Sorghum bicolor L.) using Glycine Betaine
Authors: Kumar Praveen , Tokas Jayanti , Singal H. R.
Published: November 2019

The main objective of the present research work was to study the effect of Cr toxicity and its amelioration by glycine betaine (GB) in sorghum (HJ 541 and SSG 59-3). Chromium (Cr VI), 2 and 4 ppm led to a significant reduction in plant height, root length, chlorophyll content, antioxidant enzymes viz. catalase, peroxidase, ascorbate peroxidase, glutathione reductase, polyphenol oxidase, and superoxide dismutase; and metabolites viz. ascorbate, proline, and glutathione. The results of the present study supported the findings that the application of GB can minimize or reduce the toxic effects caused by Cr VI which reaches the plants via soil, water, and air pollution. It is concluded that GB at both 50, as well as 100 mM concentrations, successfully ameliorated Cr VI (up to 4 ppm) toxicity and its application may be recommended for crops affected by Cr VI toxicity to get better growth and yield.
Age and hippocampal volume predict distinct parts of default mode network activity
Authors: De Marco Matteo , Ourselin Sebastien , Venneri Annalena
Published: November 2019

Group comparison studies have established that activity in the posterior part of the default-mode network (DMN) is down-regulated by both normal ageing and Alzheimer’s disease (AD). In this study linear regression models were used to disentangle distinctive DMN activity patterns that are more profoundly associated with either normal ageing or a structural marker of neurodegeneration. 312 datasets inclusive of healthy adults and patients were analysed. Days of life at scan (DOL) and hippocampal volume were used as predictors. Group comparisons confirmed a significant association between functional connectivity in the posterior cingulate/retrosplenial cortex and precuneus and both ageing and AD. Fully-corrected regression models revealed that DOL significantly predicted DMN strength in these regions. No such effect, however, was predicted by hippocampal volume. A significant positive association was found between hippocampal volumes and DMN connectivity in the right temporo-parietal junction (TPJ). These results indicate that postero-medial DMN down-regulation may not be specific to neurodegenerative processes but may be more an indication of brain vulnerability to degeneration. The DMN-TPJ disconnection is instead linked to the volumetric properties of the hippocampus, may reflect early-stage regional accumulation of pathology and might be of aid in the clinical detection of abnormal ageing.