bluuebunny/crossref_metadata_2025 huggingface dataset:
Model-driven development platform selection: four industry case studies
Authors: Farshidi Siamak , Jansen Slinger , Fortuin Sven
Published: January 2021

Model-driven development platforms shift the focus of software development activity from coding to modeling for enterprises. A significant number of such platforms are available in the market. Selecting the best fitting platform is challenging, as domain experts are not typically model-driven deployment platform experts and have limited time for acquiring the needed knowledge. We model the problem as a multi-criteria decision-making problem and capture knowledge systematically about the features and qualities of 30 alternative platforms. Through four industry case studies, we confirm that the model supports decision-makers with the selection problem by reducing the time and cost of the decision-making process and by providing a richer list of options than the enterprises considered initially. We show that having decision knowledge readily available supports decision-makers in making more rational, efficient, and effective decisions. The study’s theoretical contribution is the observation that the decision framework provides a reliable approach for creating decision models in software production.
FTIR Spectroscopy Detects Intermolecular β-Sheet Formation Above the High Temperature Tm for Two Monoclonal Antibodies
Authors: Baird Garrett , Farrell Chris , Cheung Jason , Semple Andrew , Blue Jeffery , Ahl Patrick L.
Published: January 2021

The temperature-dependent secondary structure of two monoclonal IgG antibodies, anti-IGF1R and anti-TSLP, were examined by transmission mode Fourier Transform Infrared (FTIR) spectroscopy. Anti-IGF1R and anti-TSLP are IgG monoclonal antibodies (mAbs) directed against human Insulin-like Growth Factor 1 Receptor for anti-tumor activity and Thymic Stromal Lymphopoietin cytokine for anti-asthma activity, respectively. Differential scanning calorimetry (DSC) clearly indicates both antibodies in their base formulations have a lower temperature protein conformational change near 70 °C (Tm1) and a higher temperature protein conformational change near 85 °C (Tm2). Thermal scanning dynamic light scatting (TS-DLS) indicates a significant particle size increase for both antibodies near Tm2 suggesting a high level of protein aggregation. The nature of these protein conformational changes associated with increasing the formulation temperature and decreasing sucrose concentration were identified by transmission mode FTIR and second derivative FTIR spectroscopy of temperature controlled aqueous solutions of both monoclonal antibodies. The transition from intra-molecular β sheets to inter-molecular β sheets was clearly captured for both monoclonal antibodies using FTIR spectroscopy. Finally, FTIR Spectroscopy was able to show the impact of a common excipient such as sucrose on the stability of each monoclonal antibody, further demonstrating the usefulness of FTIR spectroscopy for studying protein aggregation and formulation effects.
Heterologous Expression of the Barley (Hordeum vulgare L.) Xantha-f, -g and -h Genes that Encode Magnesium Chelatase Subunits
Authors: Mahdi Rabab , Stuart David , Hansson Mats , Youssef Helmy M.
Published: January 2021

Biosynthesis of chlorophyll involves several enzymatic reactions of which many are shared with the heme biosynthesis pathway. Magnesium chelatase is the first specific enzyme in the chlorophyll pathway. It catalyzes the formation of Mg-protoporphyrin IX from the insertion of Mg2+ into protoporphyrin IX. The enzyme consists of three subunits encoded by three genes. The three genes are named Xantha-h, Xantha-g and Xantha-f in barley (Hordeum vulgare L.). The products of the genes have a molecular weight of 38, 78 and 148 kDa, respectively, as mature proteins in the chloroplast. Most studies on magnesium chelatase enzymes have been performed using recombinant proteins of Rhodobacter capsulatus, Synechocystis sp. PCC6803 and Thermosynechococcus elongatus, which are photosynthetic bacteria. In the present study we established a recombinant expression system for barley magnesium chelatase with the long-term goal to obtain structural information of this enigmatic enzyme complex from a higher plant. The genes Xantha-h, -g and -f were cloned in plasmid pET15b, which allowed the production of the three subunits as His-tagged proteins in Escherichia coli BL21(DE3)pLysS. The purified subunits stimulated magnesium chelatase activity of barley plastid extracts and produced activity in assays with only recombinant proteins. In preparation for future structural analyses of the barley magnesium chelatase, stability tests were performed on the subunits and activity assays were screened to find an optimal buffer system and pH.
Saying no (to a story): personal identity and negativity
Authors: Matějčková Tereza
Published: January 2021

The concept of narrativity and narrative identity has two birth certificates: it is linked to the phenomenological tradition—beginning with Arendt’s “political phenomenology” —andto the tradition of German Idealism gradually slipping into existentialism. In this article, the author focuses on the latter tradition that helped to pave the way of the concept of narrative self. Key among the thinkers of Classical German Idealism has been Hegel, often consideredthephilosophical storyteller. Yet the author argues that Hegel’s concept of narrativity isnotexclusively applied to the self and has hardly any role in the constitution of consciousness. This is the reason why Hegel (rather than thinkers who place the core of personal identity into narrativity) has the means to formulate a more convincing concept of the self and personal identity. The author does not deny that narrativity is seminal, both for leading a life as a human being and as a concrete person; however, originally consciousness and self-hood are born out of negativity. One enacts one’s selfhood, once one realizes that one has to interrupt narrativity, step in, refuse to live by it, or just ordinarily rephrase it consciously and by this appropriate it.
The nascent ecology of social enterprise
Authors: Haugh Helen , Robson Paul , Hagedoorn John , Sugar Kate
Published: January 2021

Employing population ecology theory, we examine social enterprise population emergence in the UK after 2005 when a new organizational form for social enterprise was established. Our density dependence analysis of nearly seven thousand community interest companies finds that survival is positively influenced by age and population densities of both other social enterprises and commercial organizations. Two specific patterns in population emergence are identified: social enterprise survival is more likely influenced by industry than age, a finding that we label the liability of specificity, and their survival benefits from the population density of commercial organizations but not non-profit organizations, a finding that we label the hybrid-commercial benefit. Our research identifies the liability of specificity as a new concept in population ecology theory and the hybrid-commercial benefit as a contextual influence on social enterprise survival.
New trajectories or accelerating change? Zooarchaeological evidence for Roman transformation of animal husbandry in Northern Italy
Authors: Trentacoste Angela , Nieto-Espinet Ariadna , Guimarães Silvia , Wilkens Barbara , Petrucci Gabriella , Valenzuela-Lamas Silvia
Published: January 2021

Throughout the Western provinces of the Roman Empire, greater economic and political connectivity had a major impact on agricultural production, which grew in scale and specialisation after integration with the Roman state. However, uniquely in Western Europe, farming strategies in Italy began to evolve centuries before the Roman conquest, and many ‘Roman’ patterns associated with livestock size and the relative proportions of different taxa first emerged during the early and middle centuries of the first millennium BC. These changes imply a significant reorganisation of production strategies well before Roman hegemony, even in relatively marginal areas of Italy. Zooarchaeological studies have documented further significant changes to livestock production in Roman times, but the relationship between these developments and earlier trends remains unclear. Through analysis of zooarchaeological data for species representation and livestock biometry from lowland northern Italy (Po–Friulian Plain), this study investigates animal exploitation between the Bronze Age and Late Antiquity in order to characterise the influence of Roman political and economic organisation on animal husbandry. Results demonstrated subregional variation in species representation, and different trajectories in the biometric evolution of cattle, sheep and goats, compared to pigs. Initial steps established in the Iron Age towards a more complex and dynamic livestock economy were accelerated and further reconfigured in Roman times, facilitated by Roman economic organisation and the specialised and large-scale production systems within it. Zooarchaeological trends continued to progress over the Roman period, until further changes at the very end of the chronology considered here—around the sixth century AD—suggest another wave of change.
Para-organic intensification of future farming as alternative concept to reactor-based staple food production in Africa
Authors: Neuhoff Daniel , Kwesiga Julius
Published: January 2021

Currently, staple food self-sufficiency in Africa is just above 80%, and the population is expected to more than double until 2050. To cope with this challenge, technological solutions such as reactor food seem seductive. Western pilot projects have shown considerable production potentials, e.g., 7 t ha−1 of starch within 150 days by algae in reactors that may also be used in Africa. Are these approaches suitable for Africa justifying extensive research activities? Here, we argue that both physical availability of substrates and missing profitability substantially limit the development of reactor food in SSA, also in a mid-term perspective. It is rather suggested to close the considerable existing yield gaps by implementing para-organic farming systems, which combine basic principles of organic farming such as crop diversification, legume growing, and manuring, with a reasonable use of inputs, in particular mineral fertilizers. In combination with irrigation, staple food production in SSA has the potential to keep pace with growing demand.
From the laboratory to the end-user: a primary packaging study for microneedle patches containing amoxicillin sodium
Authors: McAlister Emma , Kearney Mary-Carmel , Martin E. Linzi , Donnelly Ryan F.
Published: January 2021

As microneedle (MN) patches progress towards commercialisation, there is a need to address issues surrounding their translation from the laboratory to the end-user. One important aspect of MN patches moving forward is appropriate primary packaging. This research focuses on MN patches containing amoxicillin (AMX) sodium for the potential treatment of neonatal sepsis in hot and humid countries. A MN patch consists of a hydrogel-forming MN array and a drug-containing reservoir. Improper primary packaging in hot and humid countries may result in degradation of active pharmaceutical ingredients, with the use of substandard medicines a major health concern. The research presented here, for the first time, seeks to investigate the integrity of MN patches in different primary packaging when stored under accelerated storage conditions, according to international guidelines. At pre-defined intervals, the performance of the MN patch was investigated. Major causes of drug instability are moisture and temperature. To avoid unnecessary degradation, suitable primary packaging was sought. After 168 days, the percentage of AMX sodium recovered from drug-containing reservoirs packaged in Protect™ 470 foil was 103.51 ± 7.03%. However, packaged in poly(ester) foil, the AMX sodium content decreased significantly (p = 0.0286), which is likely due to the degradation of AMX sodium by the imbibed moisture. Therefore, convincing evidence was provided as to the importance of investigating the stability of MN patches in primary packaging intended for MN-mediated transdermal delivery so that they are ‘fit for purpose’ when it reaches the end-user. Future work will include qualitative studies to assess MN patch usability.

Graphical abstract
alpha-2-Macroglobulin, a Native and Powerful Proteinase Inhibitor, Prevents Cartilage Degeneration Disease by Inhibiting Majority of Catabolic Enzymes and Cytokines
Authors: Zhu Mengbo , Zhao Bin , Wei Lei , Wang Shaowei
Published: January 2021

Purpose of Review

This review aims at outlining alpha-2-macroglobulin (A2M) injection, a novel non-operation strategy which could delay the process of osteoarthritis (OA). Meanwhile, some burning issues concerning “experimental” and “applied” are also indicated in this review.

Recent Findings

Many researchers have found that the alpha-2-macroglobulin, a sort of broad-spectrum proteinase inhibitor, presents remarkable inhibitive effect on intra-articular inflammation. Additionally, results of animal experiments prove that the A2M can postpone cartilage degeneration. Some treatments, such as hyaluronic acid (HA), which have been applied clinically for many years proved not to be as effective; thus, the advantage of A2M is presented.

A2M promises to be a new strategy of non-operative treatment of OA for its excellent anti-inflammation effect and biosafety. Better improved pharmaceutical preparations and treatment strategies shall be developed with the in-depth research.
Inklusive Praktiken im Mathematikunterricht. Empirische Analysen von Unterrichtsdiskursen in Einführungsphasen
Authors: Häsel-Weide Uta , Nührenbörger Marcus
Published: January 2021

Im inklusiven Mathematikunterricht werden soziale und fachliche Teilhabemöglichkeiten der Lernenden durch Praktiken des Umgangs mit dem Lerngegenstand geprägt. Im vorliegenden Beitrag wird der Frage nachgegangen, inwiefern sich diese in einführenden Unterrichtsgesprächen in der inklusiven Grundschule zeigen. Hierzu wurden 22 Klassengespräche aus kooperativ von Praxis und Forschung geplanten Unterrichtsstunden im Hinblick auf die rekonstruierbaren Praktiken untersucht. Es zeigt sich, dass der fachliche Zugang zum Gemeinsamen Gegenstand durch Praktiken der differenzierten Repräsentation und Präsentation des Gegenstands sowie der vielschichtigen Moderation derselben geprägt sind.
Sedimentology, depositional environment and classification of Karkheh River’s Delta, West of Khuzestan Plain (SW of Iran)
Authors: Abyat Ahmad , Azhdari Ali , Feghhi Amir , Judaki Mohammd
Published: January 2021

Karkheh river’s Delta is located in the west of Khuzestan Plain and can be divided into two smaller deltas; northern delta named as Karkheh Delta (including Bostan, Sableh and Neisan Deltas) and southern delta named as Karkheh -e- Noor Delta. Based on Galloway7 classification, Karkheh Delta is river-dominated type (type 1). Considering activity, this delta is divided to two parts; an active part in north and an inactive part in south. Based on Orton and Reading 16 classification, Karkheh Delta is placed in fine-grained (muddy) delta category due to prevailing silt and clay. In terms of sediment transportation and deposition process, this delta is a constructive delta. To recognize changes of Karkheh Delta’s area, Landsat images 5, 7 and 8 were studied and compared using 13 satellite images from 1973 to 2016 which shows an increase in the delta’s area particularly in northern part. In order to study sedimentology of this delta, 25 samples were taken. Sediment sizing analysis results show that silt is the most abundant sediment on average in this delta whereas clay, sand and gravel are in next abundance. Due to Shepard 17 classification, in Karkheh delta, silty clay, clay silt, silt, sandy silt and clay-silt-sand were identified. Also, channel, flood plain, crevasse, levee and sabkha depositional environments could be recognized in this delta.
Investigation of the diapirism effect on increasing salinity and solubility of water resources: a case study in eastern Tehran Province
Authors: Ebadati Naser
Published: January 2021

The water potential in east of Tehran plain is different due to a variety of evaporative formations and the effects of fault structures and diapirism. In this study, the relationship between features of water sources, especially salinity with geologic settings and a structural property, is investigated. A field investigation was performed after determining the study range in the Eyvanekey area to identify the geological formations and distribution there along with the faults and salt domes locations using geological maps. Afterwards, by identifying the wells’ location and by using the decomposition results of water samples of the area, the concentration contour maps of chloride, sulphate, and sodium, among others, were plotted. The faults’ performance and the plotted maps’ interpretation showed that the highest salinity concentration lied in the eastern and southern parts of the plain; their change trend occurred in highlands towards central and western parts of the study range, which is consistent with the main river path. Considering the qualitative results of the water, the eastern and southern parts of the plain are typically of sodium chloride nature, while the water of the area is classified as non-potable in terms of potation and harmful saline with regard to agricultural use. The study findings showed that the high evaporative mass erosion rate, and gypsum and saline sediment transport have developed saline fields in the plain. On the other hand, disorganized exploitation of water sources has considerably reduced the water quality and increased the salinity in the area.
Synthesis and electrochemical study of phosphorus-doped porous carbon for supercapacitor applications
Authors: Rawal Sangeeta , Kumar Yogesh , Mandal U. K. , Kumar Ashwani , Tanwar Ruchika , Joshi Bhawana
Published: January 2021

In the present investigation, we report the incorporation of phosphorous (P) atoms in the activated carbon and study its effect on the electrochemical performance. Porous carbon is synthesized by the chemical activation method from a bioresource and then pretreated with nitric acid. Phosphorus atoms were doped by the simple chemical method. The obtained phosphorous-doped nano-materials show an appreciable change of porosity and creation of a more wide range of meso- and macropores, and this affects their adsorption and electrochemical performance. The electrochemical study shows that doped carbon obtained at 850 °C (ACtP-850) delivers the maximum specific capacitance (328 Fg−1) in neutral aqueous electrolyte (1 M Na2SO4). The doped carbon material not only exhibits good cycling performance but also the highest specific energy of 29 Wh kg−1 corresponding to a specific power of 646 W kg−1. The improved capacitive performance of phosphorous-doped porous carbon material proposes its use in energy storage applications.
RETRACTED ARTICLE: Simulation Study of Dynamic Characteristics of Hot Pepper Harvester
Authors: Kang Seokho , Kim Junhee , Kim Yeongsu , Ha Yushin , Woo Seungmin
Published: January 2021

Purpose

Determining the safety conditions of a hot pepper harvester to mechanize harvesting.

Methods

The dynamic characteristics of a hot pepper harvester were analyzed with the dynamic simulation program RecurDyn.

Results

The pepper harvester can climb a maximal slope of 25° under full loading conditions; the maximal allowable height of an obstacle over which the harvester can drive is 450 mm; the minimal rotation radius during a spin turn is 870 mm.

Conclusions

Considering its dynamic characteristics, the harvester can be applied on over 95% of domestic upland fields. The safety accident rate can be decreased with the use of the spin turn method. In conclusion, the dynamic characteristics are sufficiently safe for the domestic upland fields.
Reforecast of the November 1994 flood in Piedmont using ERA5 and COSMO model: an operational point of view
Authors: Garbero Valeria , Milelli Massimo
Published: January 2021

The scope of this work is to assess the progresses made in the warning alert system of Piedmont since the 1994 flood. We used the COSMO model at high horizontal resolution forced by ERA5 re-forecast to simulate the November 1994 event, performing also a simple sensitivity test regarding the parameterization of convection. We compared the results with the original forecast and with the available observations, in order to understand how the emission of the alert would have been affected using the current operational system.
Shakespeare and Superheroes
Authors: Kahan Jeffrey
Published: January 2021

This short book offers a series of thought experiments and invites Shakespeareans to rediscover the wonders and pleasures of fandom. It does not argue that comic books and movies can or should replace Shakespeare; the goal is to explore the values in both, to think of comics as allusively Shakespearean, telling similar stories, expressing similar concerns, exploring similar values. Shakespeare and Superheroes seeks to re-democratize criticism by encouraging all readers to engage in and to respond to literary arguments using their own common cultural language.
Strindberg on Drama and Theatre
Authors: Strindberg August
Published: January 2021

Painter, photographer, alchemist - but ultimately, playwright, and outstanding playwright at that - the figure of August Strindberg (1849–1912) towers over late-nineteenth century drama. Strindberg's electrifying theatrical work resonated with the public in his own lifetime, and continues to impress audiences around the globe today. A restless innovator of various dramatic forms, he served as a source of inspiration for legendary figures like Eugene O' Neill, Samuel Beckett, and Ingmar Bergman, and proved seminal to the development of modern drama as we know it. Though Strindberg's preface to Miss Julie and his prefatory note to A Dream Play are well known, Strindberg's frequent commentary on drama and theatre in general are less familiar, as are most of his plays. Strindberg on Drama and Theatre presents the most important of these comments, chronologically assembled and annotated, many of them published for the first time in English. An essential resource for those interested in one of our most modern playwrights, as well as a thrilling read for the dedicated theatre lover, Strindberg on Drama and Theatre provides a fascinating look at one of our most powerful dramatic voices.
The Limits of Human Rights Limits
Authors: Richardson Henry J.
Published: January 2021

Rescuing Human Rights: A Radically Moderate Approach (Rescuing) was published shortly before the outbreak in 2020 of the novel coronavirus and its myriad human rights and class issues regarding equality, discrimination, health, and labor rights of people of color. This was also prior to the concurrent public murder of George Floyd as an unarmed Black man by the Minneapolis police in late May 2020, and the resulting continuing Black Lives Matter massive national and international movement against the deaths of Floyd and others and the history of systemic American racism, including police shooting deaths, discrimination, and brutality against African Americans, particularly unarmed Black men. Such comprehensive street protests have not been seen in America since 1968. They represent, inter alia, the cover of disguises of national racism being publicly stripped away, and the national confrontation with irrefutable evidence of a wide spectrum of systemic rights violations and the deficits of American law and government to ensure African Americans’ basic rights. Further, Rescuing was published before it became fully apparent that the federal government's responses to Black Lives Matter, particularly the executive branch, would fan the racial conflicts of national mourning and demands for new justice narratives, rather than healing and unifying for American citizens as a whole, even as these protests were the most diverse in recent memory.
How populists securitize elections to win them: the 2015 double elections in Turkey
Authors: Şahin Osman
Published: January 2021

This study presents a new theoretical framework for understanding one of the ways in which populists generate support in elections. It argues that populist movements securitize elections by triggering perceptions of ontological insecurity among voters. Through this strategy, populist movements amplify voters’ negative image of the country they live in and the challenges they face, which contributes to populist movements’ electoral success. Building upon this theoretical framework, this study offers an explanation for the 2015 double general elections in Turkey. The Justice and Development Party (Adalet ve Kalkınma Partisi, AKP) experienced disappointment after losing its parliamentary majority in the June 2015 elections. However, the AKP increased its votes by 8.6 percent in the November 2015 elections. Between these two elections, the AKP had used the Kurdish question to trigger perceptions of ontological insecurity, which enabled it to securitize the elections in November. This strategy helped the AKP win the November elections.
Influence of Mantle Dynamic Topographical Variations on US Mid‐Atlantic Continental Margin Estimates of Sea‐Level Change
Authors: Schmelz William J. , Miller Kenneth G. , Kopp Robert E. , Mountain Gregory S. , Browning James V.
Published: January 2021

Spatial analysis of discrepancies in sea‐level estimates derived from “backstripping” Mid‐Atlantic margin cores reveals a coherent signal that can be fit with a 103 km wavelength, 45 m amplitude sinusoid that moved across the margin at a rate and direction of motion generally opposite to that of the North American Plate. This signal we observe suggests topographical uplift occurred over much of the Mid‐Atlantic region since 35 Ma and may be superimposed upon a longer‐wavelength signal of Cenozoic subsidence associated with the subducted Farallon plate passing beneath the Mid‐Atlantic margin. Our statistical modeling of Mid‐Atlantic margin strata suggests that: (a) Cenozoic subsidence is likely to have occurred, but is very unlikely to have exceeded 100 m in magnitude; and (b) variations in ocean basin volume are likely to have contributed to 39 ± 24 m (1σ) of global‐mean geocentric sea‐level fall over the past 55 million years.
Permeability of Uniformly Graded 3D Printed Granular Media
Authors: Wei Deheng , Wang Zhongzheng , Pereira Jean‐Michel , Gan Yixiang
Published: January 2021

The present work explores water permeability of uniformly graded irregular grains using 3D printing with controlled shapes and fractal morphological features at low Reynold's number for viscous flow. From large amount of real 3D granular morphological data, a scaling law, in terms of fractal dimension, is found to be followed. With this universal law, sand grains with controlled fractal morphological features are generated using Spherical Harmonics, and then created using 3D printing technique for water permeability tests. A modified Kozeny‐Carman equation is proposed through more accurate determination of specific area, as a function of relative roughness and fractal dimension, than approximation using the volume‐equivalent sphere. By isolating the contributions from specific area, the shape coefficient is found to be insensitive to particle morphology. Through benchmarking the model prediction against experiments from both this work and past literature, we demonstrate the validity and wide applicability of the modified Kozeny‐Carman equation.
Landslide Geometry Reveals its Trigger
Authors: Rana Kamal , Ozturk Ugur , Malik Nishant
Published: January 2021

Electronic databases of landslides seldom include the triggering mechanisms, rendering these inventories unusable for landslide hazard modeling. We present a method for classifying the triggering mechanisms of landslides in existing inventories, thus, allowing these inventories to aid in landslide hazard modeling corresponding to the correct event chain. Our method uses various geometric characteristics of landslides as the feature space for the machine‐learning classifier random forest, resulting in accurate and robust classifications of landslide triggers. We applied the method to six landslide inventories spread over the Japanese archipelago in several different tests and training configurations to demonstrate the effectiveness of our approach. We achieved mean accuracy ranging from 67% to 92%. We also provide an illustrative example of a real‐world usage scenario for our method using an additional inventory with unknown ground truth. Furthermore, our feature importance analysis indicates that landslides having identical trigger mechanisms exhibit similar geometric properties.
Global Distribution of Reversed Energy Spectra of Ring Current Protons Based on Van Allen Probes Observations
Authors: Yi Juan , Fu Song , Ni Binbin , Gu Xudong , Hua Man , Xiang Zheng , Cao Xing , Shi Run , Zhao Yiwen
Published: January 2021

Energy spectra of ring current protons are crucial to understanding the ring current dynamics. Based on high‐quality Van Allen Probes RBSPICE measurements, we investigate the global distribution of the reversed proton energy spectra using the 2013–2019 RBSPICE data sets. The reversed proton energy spectra are characterized by the distinct flux minima around 50–100 keV and flux maxima around 200–400 keV. Our results show that the reversed proton energy spectrum is prevalent inside the plasmasphere, with the occurrence rates >90% at L ∼ 2–4 during geomagnetically quiet periods. Its occurrence also manifests a significant decrease trend with increasing L‐shell and enhanced geomagnetic activity. It is indicated that the substorm‐associated and/or convection processes are likely to lead to the disappearances of the reversed spectra. These results provide important clues for exploring the underlying physical mechanisms responsible for the formation and evolution of reversed proton energy spectra.
Multipoint Observations of Quasiperiodic Emission Intensification and Effects on Energetic Electron Precipitation
Authors: Li Jinxing , Bortnik Jacob , Ma Qianli , Li Wen , Shen Xiaochen , Nishimura Yukitoshi , An Xin , Thaller Scott , Breneman Aaron , Wygant John , Kurth William S. , Hospodarsky George B. , Hartley David P. , Reeves Geoffrey D. , Funsten Herbert O. , Blake J. Bernard , Spence Harlan , Baker Daniel N.
Published: January 2021

The two Van Allen Probes simultaneously recorded a coherently modulated quasiperiodic (QP) emission that persisted for 3 h. The magnetic field pulsation at the locations of the two satellites showed a substantial difference, and their frequencies were close to but did not exactly match the repetition frequency of QP emissions for most of the time, suggesting that those coherent QP emissions probably originated from a common source, which then propagated over a broad area in the magnetosphere. The QP emissions were amplified by local anisotropic electron distributions, and their large‐scale amplitudes were modulated by the plasma density. A novel observation of this event is that chorus waves at frequencies above QP emissions exhibit a strong correlation with QP emissions. Those chorus waves intensified when the QP emissions reach their peak frequency. This indicates that embryonic QP emissions may be critical for its own intensification as well as chorus waves under certain circumstances. A Low‐Earth‐Orbit POES satellite observed enhanced energetic electron precipitation in conjunction with the Van Allen Probes, providing direct evidence that QP emissions precipitate energetic electrons into the atmosphere. This scenario is quantitatively confirmed by our quasilinear diffusion simulation results.
Observations of the Beam‐Driven Whistler Mode Waves in the Magnetic Reconnection Region at the Dayside Magnetopause
Authors: Zhao S. Q. , Xiao C. J. , Liu Terry Z. , Chen Huayue , Zhang H. , Shi M. J. , Teng Shangchun , Zhang H. S. , Wang X. G. , Pu Z. Y. , Liu M. Z.
Published: January 2021

We report observations of the whistler mode waves in the magnetic reconnection region at the dayside magnetopause using the magnetospheric multiscale (MMS) mission on January 11, 2016. In this event, whistlers mostly occur on the magnetospheric side of the reconnection central plane and are closely related to counter‐streaming electron beams in the medium energy range (200–300 eV). These counter‐streaming electron beams can be attributed to the accelerated magnetosheath electrons by the reconnection. Through quantitatively testing the Landau resonance condition and solving the kinetic dispersion relations, we present the evidence for whistler excitation by electron beams in the medium energy range. Additionally, the whistlers are observed simultaneously with the pitch‐angle scattering of electrons in the high‐energy range (300–3,000 eV). The calculation results show that this scattering is likely to occur through electron cyclotron wave‐particle interactions, which can isotropize electrons and exchange energy between plasmas and waves.
New Methods for Data Stacking and P‐ and S‐wave Arrival Time Determination Using the Deep Moonquake Apollo Recordings
Authors: Yuan Yuefeng , Garnero Edward J. , Zhu Peimin , Lin Pei‐ying , Weber Renee C. , Wang Fenghua
Published: January 2021

A new method of simultaneous time domain cross‐correlation of multiple components of motion at multiple seismic stations is developed for P‐ and S‐wave identification for determination of arrival times of deep moonquakes using Apollo Passive Seismic Experiment (APSE) data. Deep moonquakes occur in selenographically isolated clusters, allowing the stacking of a large number of moonquakes in each cluster to improve signal‐to‐noise ratio. The method developed here seeks to improve upon multichannel cross‐correlation (MCCC) of a single component of motion and multiple events used in past work by incorporating all components and stations simultaneously. This multicomponent multichannel cross‐correlation (MCMCCC) method not only maximizes the inherent correlation between the 12 components (three components of motion at each of four stations) across all events in a given cluster, but also establishes representative stacked traces of moonquakes within each cluster. Additionally, the MCMCCC method utilizes components and events with the highest data quality to guide the inclusion of lower quality components and events (or events with fewer components). A closure difference residual time is introduced to identify moonquake events with better data and/or close source locations, to further improve the signal‐to‐noise ratio of stacked traces. A multicomponent short‐term to long‐term average algorithm is also developed to objectively determine P‐ and S‐wave arrivals that best align with their travel time curves based on lunar velocity models, simultaneously for all 12 components of motion. Newly computed deep moonquake cluster stacks and some updated deep moonquake cluster locations are presented, which improve upon past results.
An Instrument With Constant Volume Approach for In Situ Measurement of Surface Runoff and Suspended Sediment Concentration
Authors: Zhan Xiaoyun , Zhao Jun , Zhu‐Barker Xia , Shui Junfeng , Liu Baoyuan , Guo Minghang
Published: January 2021

There is an increasing demand for reliable methods to measure soil loss in order to get a better understanding of sediment movement and to develop process‐based sediment transport models. This study described the design, calibration, and practical application of an instrumented technique that automatically characterized surface flow in situ fields. The instrument consisted of a sampling assembly, a measuring assembly, and a management platform. The special design combined with a volume‐mass conversion relationship was used to determine the exact volume and mass of the sediment‐laden water, thereby allowing the implementation of real‐time measurement and synchronous calculation of runoff rate and sediment concentration. Calibration results showed that normal distributions and an average error of −3.67% were obtained for the target sediment concentrations of 2–1,000 g/L. Compared with the gravimetric method, the average error of the new technique for sediment concentration was 4.82%, and the highest precision was 98.50%. The high repeatability and accuracy of the technique suggest that it can be used with confidence to give satisfactory results in fields. A field experiment under natural rainfall showed that a grass‐covered plot had 18.94% less runoff rate and 42.92% lower sediment concentration than a bare soil plot, illustrating the impact of vegetation cover on reducing soil loss. This uniquely designed instrument provides a new approach to real‐time sediment detection in surface flow. It will be beneficial for rigorously evaluating runoff and sedimentation and for in‐depth research regarding water and soil loss processes.
Juno Maps Water Ice Across Northern Ganymede
Authors: Rehnberg Morgan
Published: January 2021

Infrared observations from instruments on the Juno spacecraft cover regions of Ganymede not visible to Earth-based telescopes.
Large and sensitive magnetostriction in ferromagnetic composites with nanodispersive precipitates
Authors: Gou Junming , Ma Tianyu , Liu Xiaolian , Zhang Changsheng , Sun Liangwei , Sun Guangai , Xia Weixing , Ren Xiaobing
Published: January 2021

Large and sensitive magnetostriction (large strain induced by small magnetic fields) is highly desired for applications of magnetostrictive materials. However, it is difficult to simultaneously improve magnetostriction and reduce the switching field because magnetostriction and the switching field are both proportional to the magnetocrystalline anisotropy. To solve this fundamental challenge, we report that introducing tetragonal nanoprecipitates into a cubic matrix can facilitate large and sensitive magnetostriction even in random polycrystals. As exhibited in a proof-of-principle reference, Fe–Ga alloys, the figure of merit—defined by the saturation magnetostriction over the magnetocrystalline anisotropy constant—can be enhanced by over 5-fold through optimum aging of the solution-treated precursor. On the one hand, the aging-induced nanodispersive face-centered tetragonal (FCT) precipitates create local tetragonal distortion of the body-centered cubic (BCC) matrix, substantially enhancing the saturation magnetostriction to be comparable to that of single crystal materials. On the other hand, these precipitates randomly couple with the matrix at the nanoscale, resulting in the collapse of net magnetocrystalline anisotropy. Our findings not only provide a simple and feasible approach to enhance the magnetostriction performance of random polycrystalline ferromagnets but also provide important insights toward understanding the mechanism of heterogeneous magnetostriction.
Enantioselective preparation of mechanically planar chiral rotaxanes by kinetic resolution strategy
Authors: Imayoshi Ayumi , Lakshmi Bhatraju Vasantha , Ueda Yoshihiro , Yoshimura Tomoyuki , Matayoshi Aki , Furuta Takumi , Kawabata Takeo
Published: January 2021

Asymmetric synthesis of mechanically planar chiral rotaxanes and topologically chiral catenanes has been a long-standing challenge in organic synthesis. Recently, an excellent strategy was developed based on diastereomeric synthesis of rotaxanes and catenanes with mechanical chirality followed by removal of the chiral auxiliary. On the other hand, its enantioselective approach has been quite limited. Here, we report enantioselective preparation of mechanically planar chiral rotaxanes by kinetic resolution of the racemates via remote asymmetric acylation of a hydroxy group in the axis component, which provides an unreacted enantiomer in up to >99.9% ee in 29% yield (the theoretical maximum yield of kinetic resolution of racemate is 50%). While the rotaxane molecules are expected to have conformational complexity, our original catalysts enabled to discriminate the mechanical chirality of the rotaxanes efficiently with the selectivity factors in up to 16.
A fourth-generation high-dimensional neural network potential with accurate electrostatics including non-local charge transfer
Authors: Ko Tsz Wai , Finkler Jonas A. , Goedecker Stefan , Behler Jörg
Published: January 2021

Machine learning potentials have become an important tool for atomistic simulations in many fields, from chemistry via molecular biology to materials science. Most of the established methods, however, rely on local properties and are thus unable to take global changes in the electronic structure into account, which result from long-range charge transfer or different charge states. In this work we overcome this limitation by introducing a fourth-generation high-dimensional neural network potential that combines a charge equilibration scheme employing environment-dependent atomic electronegativities with accurate atomic energies. The method, which is able to correctly describe global charge distributions in arbitrary systems, yields much improved energies and substantially extends the applicability of modern machine learning potentials. This is demonstrated for a series of systems representing typical scenarios in chemistry and materials science that are incorrectly described by current methods, while the fourth-generation neural network potential is in excellent agreement with electronic structure calculations.
Chromosome-level genome assembly of Ophiorrhiza pumila reveals the evolution of camptothecin biosynthesis
Authors: Rai Amit , Hirakawa Hideki , Nakabayashi Ryo , Kikuchi Shinji , Hayashi Koki , Rai Megha , Tsugawa Hiroshi , Nakaya Taiki , Mori Tetsuya , Nagasaki Hideki , Fukushi Runa , Kusuya Yoko , Takahashi Hiroki , Uchiyama Hiroshi , Toyoda Atsushi , Hikosaka Shoko , Goto Eiji , Saito Kazuki , Yamazaki Mami
Published: January 2021

Plant genomes remain highly fragmented and are often characterized by hundreds to thousands of assembly gaps. Here, we report chromosome-level reference and phased genome assembly ofOphiorrhiza pumila, a camptothecin-producing medicinal plant, through an ordered multi-scaffolding and experimental validation approach. With 21 assembly gaps and a contig N50 of 18.49 Mb,Ophiorrhizagenome is one of the most complete plant genomes assembled to date. We also report 273 nitrogen-containing metabolites, including diverse monoterpene indole alkaloids (MIAs). A comparative genomics approach identifies strictosidine biogenesis as the origin of MIA evolution. The emergence of strictosidine biosynthesis-catalyzing enzymes precede downstream enzymes’ evolution post γ whole-genome triplication, which occurred approximately 110 Mya inO. pumila, and before the whole-genome duplication inCamptotheca acuminataidentified here. Combining comparative genome analysis, multi-omics analysis, and metabolic gene-cluster analysis, we propose a working model for MIA evolution, and a pangenome for MIA biosynthesis, which will help in establishing a sustainable supply of camptothecin.
The circadian cryptochrome, CRY1, is a pro-tumorigenic factor that rhythmically modulates DNA repair
Authors: Shafi Ayesha A. , McNair Chris M. , McCann Jennifer J. , Alshalalfa Mohammed , Shostak Anton , Severson Tesa M. , Zhu Yanyun , Bergman Andre , Gordon Nicolas , Mandigo Amy C. , Chand Saswati N. , Gallagher Peter , Dylgjeri Emanuela , Laufer Talya S. , Vasilevskaya Irina A. , Schiewer Matthew J. , Brunner Michael , Feng Felix Y. , Zwart Wilbert , Knudsen Karen E.
Published: January 2021

Mechanisms regulating DNA repair processes remain incompletely defined. Here, the circadian factor CRY1, an evolutionally conserved transcriptional coregulator, is identified as a tumor specific regulator of DNA repair. Key findings demonstrate that CRY1 expression is androgen-responsive and associates with poor outcome in prostate cancer. Functional studies and first-in-field mapping of the CRY1 cistrome and transcriptome reveal that CRY1 regulates DNA repair and the G2/M transition. DNA damage stabilizes CRY1 in cancer (in vitro, in vivo, and human tumors ex vivo), which proves critical for efficient DNA repair. Further mechanistic investigation shows that stabilized CRY1 temporally regulates expression of genes required for homologous recombination. Collectively, these findings reveal that CRY1 is hormone-induced in tumors, is further stabilized by genomic insult, and promotes DNA repair and cell survival through temporal transcriptional regulation. These studies identify the circadian factor CRY1 as pro-tumorigenic and nominate CRY1 as a new therapeutic target.
Pore-forming Esx proteins mediate toxin secretion by Mycobacterium tuberculosis
Authors: Tak Uday , Dokland Terje , Niederweis Michael
Published: January 2021

Mycobacterium tuberculosis secretes the tuberculosis necrotizing toxin (TNT) to kill host cells. Here, we show that the WXG100 proteins EsxE and EsxF are essential for TNT secretion. EsxE and EsxF form a water-soluble heterodimer (EsxEF) that assembles into oligomers and long filaments, binds to membranes, and forms stable membrane-spanning channels. Electron microscopy of EsxEF reveals mainly pentameric structures with a central pore. Mutations of both WXG motifs and of a GXW motif do not affect dimerization, but abolish pore formation, membrane deformation and TNT secretion. The WXG/GXW mutants are locked in conformations with altered thermostability and solvent exposure, indicating that the WXG/GXW motifs are molecular switches controlling membrane interaction and pore formation. EsxF is accessible on the bacterial cell surface, suggesting that EsxEF form an outer membrane channel for toxin export. Thus, our study reveals a protein secretion mechanism in bacteria that relies on pore formation by small WXG proteins.
The nature of active sites for carbon dioxide electroreduction over oxide-derived copper catalysts
Authors: Cheng Dongfang , Zhao Zhi-Jian , Zhang Gong , Yang Piaoping , Li Lulu , Gao Hui , Liu Sihang , Chang Xin , Chen Sai , Wang Tuo , Ozin Geoffrey A. , Liu Zhipan , Gong Jinlong
Published: January 2021

The active sites for CO2 electroreduction (CO2R) to multi-carbon (C2+) products over oxide-derived copper (OD-Cu) catalysts are under long-term intense debate. This paper describes the atomic structure motifs for product-specific active sites on OD-Cu catalysts in CO2R. Herein, we describe realistic OD-Cu surface models by simulating the oxide-derived process via the molecular dynamic simulation with neural network (NN) potential. After the analysis of over 150 surface sites through NN potential based high-throughput testing, coupled with density functional theory calculations, three square-like sites for C–C coupling are identified. Among them, Σ3 grain boundary like planar-square sites and convex-square sites are responsible for ethylene production while step-square sites, i.e. n(111) × (100), favor alcohols generation, due to the geometric effect for stabilizing acetaldehyde intermediates and destabilizing Cu–O interactions, which are quantitatively demonstrated by combined theoretical and experimental results. This finding provides fundamental insights into the origin of activity and selectivity over Cu-based catalysts and illustrates the value of our research framework in identifying active sites for complex heterogeneous catalysts.