bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of marine environment on electrical output characteristics of PV module
Authors: Zhang Yan , Yuan Chengqing
Published: September 2021

In the context of green ships, solar photovoltaic (PV) as an important clean energy technology has attracted the attention of many scholars in the shipping industry. To ensure the stable electrical output of PV modules is the premise for the effective use of solar photovoltaic technology on ships. Different from the terrestrial environment, the disturbance of marine environmental factors to the electrical output characteristics of PV modules should be considered. It is clear that salt spray and seawater are the most important marine environmental factors that affect the electrical output characteristics of PV modules, and the corresponding mechanism is analyzed. A marine environment simulation experimental platform for PV modules is built, and experiment verification is carried out. The results show that salt spray and seawater have different perturbations on the electrical output characteristics of PV modules, and the effects will change with the change of salt spray and seawater. The combined influence of salt spray on the electrical output of the PV module is a maximum power reduction of about 6%, and the combined influence of seawater on the electrical output of the PV module is a maximum power increase of about 20%. The experiment results can provide the research basis for further research on environmental disturbance suppression methods for PV modules.
A versatile electrochemical cell for hanging meniscus or flow cell measurement of planar model electrodes characterized with scanning tunneling microscopy and x-ray photoelectron spectroscopy
Authors: Sun Zhaozong , Lauritsen Jeppe V.
Published: September 2021

We demonstrate the development of a portable electrochemistry (EC) cell setup that can be applied to measure relevant electrochemical signals on planar samples in conjunction with pre- and post-characterization by surface science methods, such as scanning tunneling microscopy and x-ray photoelectron spectroscopy. The EC cell setup, including the transfer and EC cell compartments, possesses the advantage of a small size and can be integrated with standard ultra-high vacuum (UHV) systems or synchrotron end-stations by replacing the flange adaptor, sample housing, and transfer arm. It allows a direct transfer of the pre-characterized planar sample from the UHV environment to the EC cell to conduct in situ electrochemical measurements without exposing to ambient air. The EC cell setup can operate in both the hanging meniscus and flow cell mode. As a proof of concept, using a Au(111) single crystal electrode, we demonstrate the application of the EC cell setup in both modes and report on the post-EC structure and chemical surface composition as provided by scanning tunneling microscopy and x-ray photoelectron spectroscopy. To exemplify the advantage of an in situ EC cell, the EC cell performance is further compared to a corresponding experiment on a Au(111) sample measured by transfer at ambient conditions. The EC cell demonstrated here enables a wealth of future electrocatalysis measurements that combine surface science model catalyst approaches to facilitate the understanding of nano- and atomic-scale structures of electrocatalytic interfaces, the crucial role of catalyst stability, and the nature of low-concentration and atomically dispersed metal (single atom) dopants.
On two approaches to the third-order solution of surface gravity waves
Authors: Gao Zhe , Sun Z. C. , Liang S. X.
Published: September 2021

A third-order approximate solution for surface gravity waves in the finite water depth is studied in the context of potential flow theory. This solution corresponds to the steady-state part of a multidirectional irregular wave field and provides explicit expressions for the surface elevation, free-surface velocity potential, and velocity potential. The amplitude dispersion relation is also provided. Two approaches are used to derive the third-order analytical solution, resulting in two types of approximate solutions: the perturbation solution and the Hamiltonian solution. The perturbation solution is obtained by a classical perturbation technique in which the time variable is expanded in multiscale to eliminate secular terms. The Hamiltonian solution is derived from the canonical transformation in the Hamiltonian theory of water waves. By comparing the two types of solutions, it is found that they are completely equivalent for the first- and second-order solutions and the nonlinear dispersion, but for the third-order part only the sum–sum terms are the same. Due to the canonical transformation that could completely separate the dynamic and bound harmonics, the Hamiltonian solutions break through the difficulty that the perturbation theory breaks down due to singularities in the transfer functions when the quartet resonance criterion is satisfied. Furthermore, it is also found that some time-averaged quantities based on the Hamiltonian solution, such as mean potential energy and mean kinetic energy, are equal to those in the initial state in which the sea surface is assumed to be a Gaussian random process. This is because there are associated conserved quantities in the Hamiltonian form. All of these show that the Hamiltonian solution is more reasonable and accurate to describe the third-order steady-state wave field. Finally, based on the Hamiltonian solution, some statistics are given such as the volume flux, skewness, excess kurtosis, and non-uniqueness of the induced mean flow and mean surface.
Improved thermal and structural stabilities of LiNi0.6Co0.2Mn0.2O2 cathode by La2Zr2O7 multifunctional modification
Authors: Gao Liufei , Chen Suhua , Zhang Guowei , Dai Zhongsheng , Yan Dong , Yang Hui Ying , Yu Caiyan , Bai Ying
Published: September 2021

Poor thermal stability and severe structural degradation of Ni-rich LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode during the (de)lithiation process hinder its further application. As a typical thermal barrier material and ion conductor, La2Zr2O7 (LZO) was herein served as the multifunctional modification layer due to its excellent thermal stability, robust chemical stability, and prominent Li+ conductivity. Through optimizing the contents of LZO, 2 wt.% LZO-coated NCM622 (2LZO-NCM) displayed the much improved cycling stability (66.0% capacity retention at 0.2 °C after 300 cycles at 55 °C) and rate capability (73.0 mAh g−1 at 5 °C) as compared with the pristine NCM622 (59.3%, 22.4  mAh g−1). An aging test, differential scanning calorimetry research, and kinetics analysis were conducted to unveil the improvement mechanism of electrochemical performances for 2LZO-NCM, mainly owing to the relieved structure degradation, boosted thermal stability, and enhanced electrochemical kinetics after LZO modification, synergistically contributing to the improved electrochemical performances. This work provides a universal avenue to enhance the thermal stability and electrochemical performances of the NCM622 cathode via employing the thermal barrier material as a coating layer, even in other cathodes beyond NCM622.
Chaos control and chaos synchronization of a multi-wing chaotic system and its application in multi-frequency weak signal detection
Authors: Li Wenjing , Li Ping , Jia Meimei
Published: September 2021

In this paper, first, a nonlinear feedback controller for achieving chaos control of a novel multi-wing chaotic system is presented. The nonlinear feedback controller has two parts. The first part is used to compensate an equilibrium point for the multi-wing chaotic system. The second part is a linear state feedback controller. The nonlinear feedback controller can globally asymptotically stabilize the multi-wing chaotic system to the equilibrium point. Stability conditions are given by using the Barbashin–Krasovskii theorem. Then, a linear state feedback controller for achieving chaos synchronization of the multi-wing chaotic system is presented. The linear state feedback controller can asymptotically stabilize the chaos synchronization error system to the origin. Stability conditions are given by using the passivity-based theory. Finally, a multi-frequency weak signal detection method is presented based on chaos control of the multi-wing chaotic system. The detection method can detect the frequencies of the weak signal and does not need to determine the critical point.
Holmium (Ho) oxide, carbide, and dioxide cation bond energies and evaluation of the Ho + O → HoO+ + e− chemi-ionization reaction enthalpy
Authors: Owen Cameron J. , Kim JungSoo , Armentrout P. B.
Published: September 2021

Guided ion beam tandem mass spectrometry (GIBMS) and quantum chemical calculations are employed to evaluate the title chemi-ionization reaction with holmium. Exchange reactions of Ho+ with O2, CO, and SO2 and HoO+ with CO, as well as collision-induced dissociation (CID) reactions of HoO+ with Xe, O2, and CO, were performed using GIBMS. Formation of HoO+ is exothermic in reactions with O2 and SO2 but endothermic for reaction with CO, as is the exchange reaction of HoO+ with CO. Quantitative analysis of these reactions and the three CID reactions provides a robust method to determine the bond dissociation energy (BDE) of Ho+–O, 6.02 ± 0.13 eV. BDEs for Ho+–C and OHo+–O are also measured as 2.27 ± 0.19 and 2.70 ± 0.27 eV, respectively. All three measurements are the first direct determinations of these BDEs. By combining the BDE of HoO+ with the well-established ionization energy of Ho, the exothermicity of Ho in the title chemi-ionization reaction can also be obtained as 0.00 ± 0.13 eV. All experimental thermochemistry was then compared to quantum chemical calculations for the purpose of establishing benchmarks and validation. BDEs determined via these calculations are in agreement with the experiment within the inherent experimental and theoretical uncertainties, with results obtained at the coupled-cluster with single, double, and perturbative triple excitations, CCSD(T), using all-electron basis sets yielding the most accurate results.
High-frequency and below bandgap anisotropic dielectric constants in α-(AlxGa1−x)2O3 (≤x≤1)
Authors: Hilfiker Matthew , Kilic Ufuk , Stokey Megan , Jinno Riena , Cho Yongjin , Xing Huili Grace , Jena Debdeep , Korlacki Rafał , Schubert Mathias
Published: September 2021

A Mueller matrix spectroscopic ellipsometry approach was used to investigate the anisotropic dielectric constants of corundum α-(AlxGa1−x)2O3 thin films in their below bandgap spectral regions. The sample set was epitaxially grown using plasma-assisted molecular beam epitaxy on m-plane sapphire. The spectroscopic ellipsometry measurements were performed at multiple azimuthal angles to resolve the uniaxial dielectric properties. A Cauchy dispersion model was applied, and high-frequency dielectric constants are determined for polarization perpendicular (ε∞,⊥) and parallel (ε∞,∥) to the thin film c-axis. The optical birefringence is negative throughout the composition range, and the overall index of refraction substantially decreases upon incorporation of Al. We find small bowing parameters of the high-frequency dielectric constants with b⊥=0.386 and b∥=0.307.
Study on a mesoscopic model of droplets freezing considering the recalescence process
Authors: Wang Chenyang , Wu Xiao , Hao Pengfei , He Feng , Zhang Xiwen
Published: September 2021

There are many practical applications of droplets freezing, and in many cases, it is necessary to prevent the droplets freezing to reduce the loss caused by freezing. Based on the many-body dissipative particle dynamics with energy conservation method, this research proposes an icing model that considers the recalescence process and initial ice mass fraction of droplets for the first time, which obtains a complete simulation of the two-phase four-stage freezing process of droplets. The accuracy and applicability of this model are verified by studying the single-phase Stefan problem, the recalescence process of droplet, and whether the initial ice mass fraction is considered for freezing. Then, the freezing process of droplets under four surface temperatures and five types of surface wettability was studied, and it was found that the temperature of droplets in recalescence stage would jump from nucleation temperature to equilibrium temperature, and almost unaffected by external factors. Change of the temperature distribution with dimensionless height H* before recalescence is only affected by the surface temperature and nucleation temperature. At the end of droplets recalescence, the initial ice mass fraction has little relationship with volume. As the contact angle, surface temperature, and droplet volume increase, temperature changes in the pre-cooling and solidification stages of droplets will slow down, and the solidification time will increase. Additionally, the temperature of the solid wall surface has almost no effect on the final ice shape, and the final ice tip phenomenon is more obvious on the surface with a larger contact angle.
Corrigendum to: Conservation of quolls (Dasyurus spp.) in captivity – a review
Authors: Old Julie M. , Stannard Hayley J.
Published: September 2021

Quolls are carnivorous marsupials in the family Dasyuridae with characteristic white spots. They are distributed throughout Australia and New Guinea, but uncommonly seen due to their mostly nocturnal solitary nature, and large home ranges. All Australian quolls are listed as ‘near threatened' or ‘endangered' at state, national and international levels, largely due to human-induced threats. Threats include introduced predators, habitat loss through clearing and modifications including changed fire regimes, disease, human persecution, vehicle collisions and accidental or targeted poisoning by humans and cane toads (Rhinella marina). Conservation efforts that have focussed on reducing introduced predators, and minimising the impact of cane toads, have aided some translocations, hence species recovery in some local areas of Australia has occurred. Where species conservation has required captive breeding for translocation, successful captive management has been crucial. We summarise research conducted in captivity on aspects of birth and development, health and disease, and blood and nutrition parameters of quolls, and suggest future directions for research. Further research on captive and wild quoll populations will benefit future translocations, reintroductions and conservation through increased knowledge, improved maintenance and husbandry of captive colonies, and monitoring of wild populations.
Translation hacking in Arabic video game localization
Authors: Al-Batineh Mohammed , Alawneh Razan
Published: September 2021

The present article discusses the notion of translation hacking and attempts to chart the history of this practice in the Arabic context. It also discusses the current practices of translation hacking by examining the work of a well-organized online community of Arab translation hackers calledGames in Arabic(GiA). To this end, the study adopts two methods for data collection. First, semi-structured interviews were conducted with the first translation hackers in the Arab world in order to document the history of this practice. Second, a cyberethnographic approach was adopted to collect qualitative data related to GiA, including their translation hacking practices and the technologies used to facilitate their collaborative work. Subsequently, this article attempts to reveal the roles played by the different GiA community members in executing their projects and how they control for quality in their work. Ultimately, the article attempts to provide insights into the practice of Arabic game localization performed by amateur translators, hackers, and gamers, in the hope of adding to current professional and pedagogical practices in Arabic game localization.
Investigation and comparison of three noval strain rate-dependent fracture criteria
Authors: Huang Yahui , Tuo Zhiyu , Qu Keyu , Yue Zhenming , Badreddine Houssem , Gao Jun , Qiu Yuliang , Sun Jiao
Published: September 2021

In this study, three new strain rate-dependent fracture criteria were proposed and studied upon DP900 steel. The damage threshold was rewritten as a function related to strain rate on the basis of Lou's fracture theory. Three different uncoupled strain rate base forms were also given: (i) two polynomial forms and (ii) one power form. The model parameters were identified and validated through uniaxial tensile and double bridge shear tests. The prediction accuracies of each model within four different strain rates were compared by contrasting and analysing the experimental and numerical results. In conclusion, the proposed fracture criteria of power form induce the results with the best agreements with experimental ones. These results prove that the proposed fracture criteria can predict ductile failure under different strain rate loadings.
Soft congestion approximation to the one-dimensional constrained Euler equations
Authors: Bianchini Roberta , Perrin Charlotte
Published: September 2021

This article is concerned with the analysis of the one-dimensional compressible Euler equations with a singular pressure law, the so-called hard sphere equation of state. We provide a detailed description of the effect of the singular pressure on the breakdown of the smooth solutions. Moreover, we rigorously justify the singular limit for smooth solutions towards the free-congested Euler equations, where the compressible (free) dynamics is coupled with the incompressible one in the constrained (i.e. congested) domain.
Thermal quench and current profile relaxation dynamics in massive-material-injection-triggered tokamak disruptions
Authors: Nardon E , Hu D , Artola F J , Bonfiglio D , Hoelzl M , Boboc A , Carvalho P , Gerasimov S , Huijsmans G , Mitterauer V , Schwarz N , Sun H , JOREK team the
Published: September 2021

3D non-linear magnetohydrodynamic simulations of a disruption triggered by a massive injection of argon gas in JET are performed with the JOREK code. The key role of the thermal drive of the m = 2, n = 1 tearing mode (i.e. the drive from helical cooling inside the island) in the disruption process is highlighted by varying the amplitude and position of the argon source across simulations, and also during a simulation. In cases where this drive persists in spite of the development of magnetic stochasticity, which is favoured by moving the argon source in an ad hoc way from the plasma edge into the 2/1 island at some point in the simulation, a relaxation in the region

q
⩽
2

(roughly) takes place. This relaxation generates a plasma current spike comparable to the experimental one. Simulations are compared in detail to measurements via synthetic diagnostics, validating the model to some degree.
Large bulk photovoltaic effect and second-harmonic generation in few-layer pentagonal semiconductors PdS2 and PdSe2
Authors: Gudelli Vijay Kumar , Guo Guang-Yu
Published: September 2021

Recently, atomically thin PdSe2 semiconductors with rare pentagonal Se–Pd–Se monolayers were synthesized and were also found to possess superior properties such as ultrahigh air stability, tunable band gap and high carrier mobility, thus offering a new family of two-dimensional (2D) materials for exploration of 2D semiconductor physics and for applications in advanced opto-electronic and nonlinear photonic devices. In this work, we systematically study the nonlinear optical (NLO) responses [namely, bulk photovoltaic effect (BPVE), second-harmonic generation (SHG) and linear electric-optic (LEO) effect] of noncentrosymmetric bilayer (BL) and four-layer PdS2 and PdSe2 by applying the first-principles density functional theory with the generalized gradient approximation plus scissors-correction. First of all, we find that these few-layer PdX
2 (X = S and Se) exhibit prominent BPVE. In particular, the calculated shift current conductivity is in the order of 130 μA V−2, being very high compared to known BPVE materials. Similarly, their injection current susceptibilities are in the order of 100 × 108 A V−2 s−1, again being large. Secondly, the calculated SHG coefficients (χ
(2)) of these materials are also large, being one order higher than that of the best-known few-layer group 6B transition metal dichalcogenides. For example, the maximum magnitude of χ
(2) can reach 1.4 × 103 pm V−1 for BL PdSe2 at 1.9 eV and 1.2 × 103 pm V−1 at 3.1 eV for BL PdS2. Thirdly we find significant LEO coefficients for these structures in the low photon energy. All these indicate that 2D PdX
2 semiconductors will find promising NLO applications in light signal modulators, frequency converters, electro-optical switches and photovoltaic solar cells. Fourthly, we find that the large BPVE and SHG of the few-layer PdX
2 structures are due to strong intralayer directional covalent bonding and also 2D quantum confinement. Finally, we also discuss the prominent features of these NLO spectra of these materials in terms of their electronic structure and optical dielectric functions.
Cold ion chemistry within a Rydberg-electron orbit: test of the spectator role of the Rydberg electron in the He(n) + CO → C(n′) + O + He reaction
Authors: Martins Fernanda B V , Zhelyazkova Valentina , Seiler Christian , Merkt Frédéric
Published: September 2021

Recently, a new method has been introduced to study ion-molecule reactions at very low collision energies, down to below k
B ⋅ 1 K (Allmendinger et al 2016 ChemPhysChem
17 3596). To eliminate the acceleration of the ions by stray electric fields in the reaction volume, the reactions are observed within the orbit of a Rydberg electron with large principal quantum number n > 20. This electron is assumed not to influence the reaction taking place between the ion core and the neutral molecules. This assumption is tested here with the example of the He(n) + CO → C(n′) + O + He reaction, which is expected to be equivalent to the He+ + CO → C+ + O + He reaction, using a merged-beam approach enabling measurements of relative reaction rates for collision energies E
coll in the range from 0 to about k
B ⋅ 25 K with a collision-energy resolution of ∼k
B ⋅ 200 mK at E
coll = 0. In contrast to the other ion-molecule reactions studied so far with this method, the atomic ion product (C+) is in its electronic ground state and does not have rotational and vibrational degrees of freedom so that the corresponding Rydberg product [C(n′)] cannot decay by autoionization. Consequently, one can investigate whether the principal quantum number is effectively conserved, as would be expected in the spectator Rydberg-electron model. We measure the distribution of principal quantum numbers of the reactant He(n) and product C(n′) Rydberg atoms by pulsed-field ionization following initial preparation of He(n) in states with n values between 30 and 45 and observe that the principal quantum number of the Rydberg electron is conserved during the reaction. This observation indicates that the Rydberg electron is not affected by the reaction, from which we can conclude that it does not affect the reaction either. This conclusion is strengthened by measurements of the collision-energy-dependent reaction yields at n = 30, 35 and 40, which exhibit the same behavior, i.e. a marked decrease below E
coll ≈ k
B ⋅ 5 K.
Effects of Different Types of Organic Fertilizer on Biomass Yield, Bioactive Compounds and Heavy Metals Contents of Phyllanthus Niruri
Authors: Zahidah A R , Rosenani A B , Hajar A S , Nozulaidi N M
Published: September 2021

This research aimed to study the effects of different types and rates of organic fertilizer on biomass yield, bioactive compounds, and heavy metals content of Phyllanthus niruri. Two types of organic fertilizers (animal-based and plant-based) with five different rates (0, 100, 200, 300, and 400 kg N ha−1) were used in this study. There was an interaction between fertilizer types and rates on biomass yield, heavy metals content, and bioactive compounds. Plants are grown with 400 kg N ha−1 of animal-based fertilizer, and plant-based fertilizer produced the highest fresh biomass. However, phyllanthin and hypophyllanthin concentrations of P. niruri were not affected by applying animal-based and plant-based fertilizers at all rates. In addition, Cd and Pb concentrations also decreased with the increasing rate of organic fertilizer and were below the Malaysia Permissible Levels (MPLs). Therefore, animal-based fertilizer at 400 kg N ha−1 was selected as the optimum rate due to its reduced heavy metal concentration in plants and higher phyllanthin and hypophyllanthin yield.
Integrated teaching of college English reading and writing under the background of big data
Authors: Sun Yangzi , Liu Chen
Published: September 2021

At present, reading and writing are divided into two independent courses in English teaching at most universities. According to the views of many scholars at home and abroad, it is more efficient to learn a language through integration of input and output, which advocates the integrated teaching of English reading and writing. The purpose of this paper is to verify whether the integration of reading and writing is helpful to the improvement of college students' ability through comparative experiment and random sampling method, and put forward an integrated learning mode of online reading and writing based on data algorithm. The main content of this paper is to elaborate the current situation of mobile reading and mobile writing in the era of big data, and then extract two groups of college students with similar learning conditions from two universities for empirical analysis, to study the differences in students' performance through comparison in the traditional reading and writing teaching mode and the new mode of integration of reading and writing teaching, and finally put forward the application of clustering algorithm based on K-Modes under the background of big data English learning scoring system, so that students can learn independently and efficiently on the Internet. The experiment shows that the average score of students in the integration of reading and writing is generally higher than that in traditional teaching. Under the integration of reading and writing, the students' reading accuracy is as high as 90%, which is 10% higher than that in the traditional way, and the score of writing is 5 points higher than that in the traditional way.
Application of BP neural network technology on dynamic financial risk prediction
Authors: Lin Huijuan , Liu Jianfei , Lu Songmin , Li Zhuohui
Published: September 2021

This work mainly studied the application of BP neural network technology. Based on the crisis early warning of listed real estate companies at home and abroad, this study used BP neural network method to determine the corporate governance indicators of crisis enterprises from eight aspects, such as profitability, solvency, operation ability, development ability, cash flow, risk, etc. This work took the real estate listed companies as the research object and put forward eight early warning indicators. Traditional early warning models have low fault tolerance, and most of them are static early warning. In this study, the innovation point is that the BP neural network model has the ability of self-learning and adjustment, strong risk identification and fault tolerance, and can cope with the changeable financial risk environment of real estate enterprises. BP neural network model can analyze problems through self-learning and training, and has strong nonlinear mapping ability. It is feasible to construct financial risk early warning model of real estate listed enterprises.
Improving Recruitment, Retention, and Cultural Saliency of Health Promotion Efforts Targeting African American Men: A Scoping Review
Authors: Wippold Guillermo M , Frary Sarah Grace , Abshire Demetrius A , Wilson Dawn K
Published: September 2021

Background

When health promotion efforts intend to include African American men, they experience challenges with recruitment and retention, in addition to limited cultural saliency—interventions that do not align the cultural preferences and experiences of the target population produce less effective results.

Purpose

This scoping review provides an understanding of (a) how health promotion efforts among African American men are developed and implemented, in addition to the (b) main outcomes, (c) retention rates, and (d) methodological rigor of those efforts.

Methods

The following databases were used: PubMed, EMBASE (Ovid), PsycINFO (EBSCO), CINAHL (EBSCO), Web of Science (Clarivate), and ProQuest. Included studies were restricted to those: (a) conducted among African American men and (b) reported the effects of a health promotion intervention. Interventions using single-group pre–post study, post-test-only study, non-randomized controlled trial, and randomized controlled trial (RCT) study designs were included.

Results

The results indicate that varying degrees of customization in the design and implementation of health promotion efforts targeting African American can improve recruitment, retention, and health-related outcomes. Results draw attention to the need for community input when designing and implementing efforts targeting these men.

Conclusions

These results indicate that opportunities exist to innovate health promotion efforts among African American men, such as the intentional incorporation of the community’s values, perspectives, and preferences in the effort (i.e., cultural saliency) and explicitly indicating how the efforts were culturally tailored to improve saliency. Opportunities also exist to innovate health promotion efforts among African American men based on literature-derived best practices.
Morpho-anatomical affinities and evolutionary relationships of three paleoendemic podocarp genera based on seed cone traits
Authors: Khan Raees , Hill Robert S
Published: September 2021

Background and Aims

The three relict genera Pherosphaera, Microcachrys and Saxegothaea in Podocarpaceae produce quite distinct seed cone types in comparison with other genera and do not form a clade along with Acmopyle. The detailed seed cone morpho-anatomy of these three relict genera and affinities with other podocarps are poorly known. This study aims to understand the seed cone morpho-anatomy and affinities among these three disjunct relict genera and with other podocarps.

Methods

We comparatively analysed the seed cone morpho-anatomical traits of the three podocarps genera and used ancestral state reconstruction to understand the evolution of these traits.

Key Results

We described the seed cone morpho-anatomical structures of the three relict genera in detail. The three genera produce aggregated multiovulate cones. Both Microcachrys and Saxegothaea have an asymmetrical free cup-like epimatium. Both species of Pherosphaera lack an epimatium. The ancestral state reconstruction implies that the presence of an epimatium is an ancestral trait in podocarps and is independently lost in Pherosphaera and Phyllocladus. The seed cones are fleshy in Microcachrys and non-fleshy in Saxegothaea and Pherosphaera. The seed cone macrofossils of both extinct and living podocarps also show the presence of an epimatium and fleshiness in podocarps.

Conclusions

Altogether, the morpho-anatomy suggests that Pherosphaera, Microcachrys and Saxegothaea present affinities with each other and other podocarps, but the reconstruction of the ancestral seed cone in Podcarpaceae is quite complex due to multiple convergent evolutions of several structures. These structures (e.g. epimatium, aril and receptaculum) are of low taxonomic value but of great evolutionary and ecological significance, and are responsive adaptations to ever-changing environmental conditions.
Conditional immobilization for live imaging Caenorhabditis elegans using auxin-dependent protein depletion
Authors: Cahoon Cori K , Libuda Diana E
Published: September 2021

The visualization of biological processes using fluorescent proteins and dyes in living organisms has enabled numerous scientific discoveries. The nematode Caenorhabditis elegans is a widely used model organism for live imaging studies since the transparent nature of the worm enables imaging of nearly all tissues within a whole, intact animal. While current techniques are optimized to enable the immobilization of hermaphrodite worms for live imaging, many of these approaches fail to successfully restrain the smaller male worms. To enable live imaging of worms of both sexes, we developed a new genetic, conditional immobilization tool that uses the auxin-inducible degron (AID) system to immobilize both adult and larval hermaphrodite and male worms for live imaging. Based on chromosome location, mutant phenotype, and predicted germline consequence, we identified and AID-tagged three candidate genes (unc-18, unc-104, and unc-52). Strains with these AID-tagged genes were placed on auxin and tested for mobility and germline defects. Among the candidate genes, auxin-mediated depletion of UNC-18 caused significant immobilization of both hermaphrodite and male worms that was also partially reversible upon removal from auxin. Notably, we found that male worms require a higher concentration of auxin for a similar amount of immobilization as hermaphrodites, thereby suggesting a potential sex-specific difference in auxin absorption and/or processing. In both males and hermaphrodites, depletion of UNC-18 did not largely alter fertility, germline progression, nor meiotic recombination. Finally, we demonstrate that this new genetic tool can successfully immobilize both sexes enabling live imaging studies of sexually dimorphic features in C. elegans.
Genome and transcriptome analysis of the beet armyworm Spodoptera exigua reveals targets for pest control
Authors: Simon Sabrina , Breeschoten Thijmen , Jansen Hans J , Dirks Ron P , Schranz M Eric , Ros Vera I D
Published: September 2021

The genus Spodoptera (Lepidoptera: Noctuidae) includes some of the most infamous insect pests of cultivated plants including Spodoptera frugiperda, Spodoptera litura, and Spodoptera exigua. To effectively develop targeted pest control strategies for diverse Spodoptera species, genomic resources are highly desired. To this aim, we provide the genome assembly and developmental transcriptome comprising all major life stages of S. exigua, the beet armyworm. Spodoptera exigua is a polyphagous herbivore that can feed on > 130 host plants, including several economically important crops. The 419 Mb beet armyworm genome was sequenced from a female S. exigua pupa. Using a hybrid genome sequencing approach (Nanopore long-read data and Illumina short read), a high-quality genome assembly was achieved (N50 = 1.1 Mb). An official gene set (18,477 transcripts) was generated by automatic annotation and by using transcriptomic RNA-seq datasets of 18 S. exigua samples as supporting evidence. In-depth analyses of developmental stage-specific expression combined with gene tree analyses of identified homologous genes across Lepidoptera genomes revealed four potential genes of interest (three of them Spodoptera-specific) upregulated during first- and third-instar larval stages for targeted pest-outbreak management. The beet armyworm genome sequence and developmental transcriptome covering all major developmental stages provide critical insights into the biology of this devastating polyphagous insect pest species worldwide. In addition, comparative genomic analyses across Lepidoptera significantly advance our knowledge to further control other invasive Spodoptera species and reveals potential lineage-specific target genes for pest control strategies.
Genetic, morphometric, and molecular analyses of interspecies differences in head shape and hybrid developmental defects in the wasp genusNasonia
Authors: Cohen Lorna B , Jewell Rachel , Moody Dyese , Arsala Deanna , Werren John H , Lynch Jeremy A
Published: September 2021

Males in the parasitoid wasp genus Nasonia have distinct, species-specific, head shapes. The availability of fertile hybrids among the species, along with obligate haploidy of males, facilitates analysis of complex gene interactions in development and evolution. Previous analyses showed that both the divergence in head shape between Nasonia vitripennis and Nasonia giraulti, and the head-specific developmental defects of F2 haploid hybrid males, are governed by multiple changes in networks of interacting genes. Here, we extend our understanding of the gene interactions that affect morphogenesis in male heads. Use of artificial diploid male hybrids shows that alleles mediating developmental defects are recessive, while there are diverse dominance relationships among other head shape traits. At the molecular level, the sex determination locus doublesex plays a major role in male head shape differences, but it is not the only important factor. Introgression of a giraulti region on chromsome 2 reveals a recessive locus that causes completely penetrant head clefting in both males and females in a vitripennis background. Finally, a third species (N. longicornis) was used to investigate the timing of genetic changes related to head morphology, revealing that most changes causing defects arose after the divergence of N. vitripennis from the other species, but prior to the divergence of N. giraulti and N. longicornis from each other. Our results demonstrate that developmental gene networks can be dissected using interspecies crosses in Nasonia, and set the stage for future fine-scale genetic dissection of both head shape and hybrid developmental defects.
Modelling tilt noise caused by atmospheric processes at long periods for several horizontal seismometers at BFO—a reprise
Authors: Zürn W , Forbriger T , Widmer-Schnidrig R , Duffner P , Ringler A T
Published: September 2021

Tilting of the ground due to loading by the variable atmosphere is known to corrupt very long period horizontal seismic records (below 10 mHz) even at the quietest stations. At BFO (Black Forest Observatory, SW-Germany), the opportunity arose to study these disturbances on a variety of simultaneously operated state-of-the-art broad-band sensors. A series of time windows with clear atmospherically caused effects was selected and attempts were made to model these ‘signals’ in a deterministic way. This was done by simultaneously least-squares fitting the locally recorded barometric pressure and its Hilbert transform to the ground accelerations in a bandpass between 100 and 3600 s periods. Variance reductions of up to 97 per cent were obtained. We show our results by combining the ‘specific pressure induced accelerations’ for the two horizontal components of the same sensor as vectors on a horizontal plane, one for direct pressure and one for its Hilbert transform. It turned out that at BFO the direct pressure effects are large, strongly position dependent and largely independent of atmospheric events for instruments installed on piers, while three post-hole sensors are only slightly affected. The infamous ‘cavity effects’ are invoked to be responsible for these large effects on the pier sensors. On the other hand, in the majority of cases all sensors showed very similar magnitudes and directions for the vectors obtained for the regression with the Hilbert transform, but highly variable from event to event especially in direction. Therefore, this direction most certainly has to do with the gradient of the pressure field moving over the station which causes a larger scale deformation of the crust. The observations are very consistent with these two fundamental mechanisms of how fluctuations of atmospheric surface pressure causes tilt noise. The results provide a sound basis for further improvements of the models for these mechanisms. The methods used here can already help to reduce atmospherically induced noise in long-period horizontal seismic records.
A record of the lower Mammoth geomagnetic polarity reversal from a marine succession in the Boso Peninsula, central Japan
Authors: Haneda Yuki , Okada Makoto
Published: September 2021

Palaeomagnetic records from geological archives provide significant information about the nature of geomagnetic polarity reversals; however, there are few detailed palaeomagnetic records of pre-Pleistocene reversals. The lower Mammoth Subchron boundary (late Pliocene) is recorded in a 10-m interval of a marine succession deposited at high accumulation rates (9–66 cm kyr–1) in the Boso Peninsula, central Japan. Here, we report a continuous palaeomagnetic record of the lower, normal to reverse boundary interval of the Mammoth Subchron, including the geomagnetic field direction and relative palaeointensity, with an average temporal resolution of ca. 800 yr. A hybrid method of thermal demagnetization at 200 °C and progressive alternating field demagnetization were used to effectively extract the primary palaeomagnetic component, which is carried by magnetite. The lower Mammoth transition is characterized by palaeomagnetic direction of instability and decay of the relative palaeointensity, and occurred from late Marine Isotope Stage MG3 (3351 ka) to MG2 (3336 ka) or MG1 (3331 ka), spanning 15–20 kyr. Virtual geomagnetic poles (VGPs), calculated from primary palaeomagnetic directions, rapidly rebounded twice from southern latitudes to northern latitudes within the transition. In contrast to the complex lower Mammoth reversal behaviour recorded in the Boso Peninsula succession, records from a lava sequence in O'ahu (Hawai'i) reveal a rebound following a 180° directional change, and those from a marl succession in Sicily (Italy) indicate a single rapid directional change. Diverse geomagnetic field evolution among these three sections is reflected resolution difference among the records likely in combination with an influence of non-axial dipole field.
3. Corporate personality
Authors: Hannigan Brenda
Published: September 2021

This chapter discusses the concept of corporate legal personality. This fundamental principle of company law—that the company on incorporation becomes a separate legal entity in its own right—was established by the House of Lords in Salomon v Salomon & Co Ltd. The Salomon principle and its consequences for individual companies and for groups of companies are considered. In limited circumstances, the court may disregard or pierce or lift the corporate veil and the narrow jurisdiction to do so is explained. The chapter also considers corporate groups in the light of Salomon, particularly with regard to the liability of parent companies for the actions of subsidiary companies.
5. The company constitution
Authors: Hannigan Brenda
Published: September 2021

This chapter focuses on the company constitution, essentially the articles of association. The chapter covers the need for articles (including the adoption of the model articles), amending the articles, interpreting the articles, enforcing the articles, and shareholders’ agreements. It particularly considers the extent to which shareholders can alter the articles and the common law limits to the power to do so. Altering the articles to allow for the compulsory transfer of members’ interests is also considered. Interpreting the articles and enforcing the statutory contract created is addressed. Shareholder agreements can provide better protection for shareholders and the chapter considers how they can supplement the company's articles.
6. Corporate governance—board structure and shareholder engagement
Authors: Hannigan Brenda
Published: September 2021

This chapter discusses the appointment and removal of directors. Directors are responsible for the management of the company’s business, for which purpose they may exercise all the powers of the company. The chapter considers three classes of directors: the de jure director, the de facto director, and the shadow director. It identifies the characteristics of each category and the liabilities which attach in the event that someone is classed as being a director. It also considers whether fiduciary duties are owed by shadow directors. The position of corporate directors is also considered. In addition, the remuneration of directors is addressed.
16. Membership and the incidents of membership
Authors: Hannigan Brenda
Published: September 2021

This chapter discusses the law on membership and the incidents of membership. The discussion covers classes of shares, class rights, share transfer and transmission, and the register of members. The chapter considers how people become members and the importance of entry on the register of members. It also considers the restrictions on access to the register and the power of the court to rectify the register when necessary to do so. It is possible to protect shareholders by providing for classes of shares and the chapter considers the protection afforded by class rights and how class rights, once created, can be varied subsequently. Share transfer and transmission is also considered.
23. Loan capital—secured creditors and company charges
Authors: Hannigan Brenda
Published: September 2021

The majority of companies rely on commercial borrowing—loan capital—from high street banks and financial institutions. The lender will need security to cover the amount lent. This chapter discusses: company charges, fixed and floating charges, the approach to categorisation, registration of charges, and enforcement of a floating charge. The key concern for the creditor is to obtain the maximum security while the company is concerned to have the maximum freedom to act. The distinction between fixed and floating charges is considered and the characteristics of a floating charge are discussed with particular regard to charges on book debts. The chapter also considers the registration requirements with the registrar of companies.
Alcohol Consumption is Associated With An Increased Risk of Microscopic Colitis: Results From 2 Prospective US Cohort Studies
Authors: Niccum Blake , Casey Kevin , Burke Kristin , Lopes Emily W , Lochhead Paul , Ananthakrishnan Ashwin , Richter James M , Ludvigsson Jonas F , Chan Andrew T , Khalili Hamed
Published: September 2021

Background

No dietary factors have yet been shown to conclusively impact the incidence of microscopic colitis (MC). Here, we sought to examine the relationship between alcohol intake and the risk of MC.

Methods

We conducted a prospective cohort study of 209,902 participants (age range, 28.5–66.7 years) enrolled in the Nurses’ Health Study (NHS) and Nurses’ Health Study II (NHSII). Validated data on alcohol consumption were collected at baseline in 1986 in the NHS and 1991 in the NHSII and updated every 4 years. Diagnoses of MC were confirmed via review of histopathology data. We used Cox proportional hazards modeling to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).

Results

Through 2016 in the NHS and 2017 in the NHSII, we confirmed 352 incident cases of MC over 4,994,324 person-years. Higher alcohol consumption was associated with an increased risk of MC (Ptrend < .001). Compared to non-users, the aHRs of MC were 1.20 (95% CI, 0.86–1.67) for consumers of 0.1–4.9 g/day of alcohol, 1.90 (95% CI, 1.34–2.71) for consumers of 5–14.9 g/day, and 2.31 (95% CI, 1.54–3.46) for consumers of ≥15 g/day. The associations were consistent across the histologic subtypes of collagenous and lymphocytic colitis (Pheterogeneity = .523). When stratified by alcohol type, the risk according to every 2 servings/week appeared to be strongest with consumption of wine (aHR, 1.08; 95% CI, 1.04–1.12) as compared to beer (aHR, 1.01; 95% CI, 0.91–1.12) or liquor (aHR, 1.00; 95% CI, 0.92–1.09).

Conclusions

Alcohol consumption was associated with an increased risk of MC. Further studies are needed to determine the mechanism underlying these associations, as well as the impact of reducing alcohol intake in patients with MC.