bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Developments of Nontraditional Single‐Molecule Toroics
Authors: Li Xiao‐Lei , Ma Zhifang , Tang Jinkui 
Published: February 2024

AbstractSingle‐molecule toroics (SMTs), defined as a type of molecules with toroidal arrangement of magnetic moment associated with bi‐stable non‐magnetic ground states, are promising candidates for high‐density information storage and the development of molecule based multiferroic materials with linear magneto–electric coupling and multiferroic behavior. The design and synthesis of SMTs by arranging the magnetic anisotropy axis in a circular pattern at the molecular level have been of great interest to scientists for last two decades since the first detection of the SMT behavior in the seminal Dy3 molecules. DyIII ion has long been the ideal candidate for constructing SMTs due to its Kramer ion nature as well as high anisotropy. Nevertheless, other LnIII ions such as TbIII and HoIII ions, as well as some paramagnetic transition metal ions, have also been used to construct many nontraditional SMTs. Therefore, we review the progress in the studies of SMTs based on the nontraditional perspective, ranging from the 3D topological to 1D&2D&3D polymeric SMTs, and 3d–4f to non Dy‐based SMTs. We hope the understanding we provide about nontraditional SMTs will be helpful in designing novel SMTs.
Pertechnetates – A Structural Study Across the Periodic Table
Authors: Strub Erik , Grödler Dennis , Zaratti Daniele , Yong Clarence , Dünnebier Lisa , Bazhenova Sonja , Roca Jungfer Maximilian , Breugst Martin , Zegke Markus 
Published: February 2024

AbstractThe number of crystal structures of pertechnetates derived from aqueous solutions has been expanded from seven to over 30. We report the conversion of NH4TcO4 to aqueous HtcO4 via acidic cation exchange. This is followed by the synthesis and structural elucidation of pertechnetate salts of alkaline earth (AE), transition metal I and lanthanoids (Ln) elements. Various degrees of hydration and coordination are discussed. Where possible, a comparison with the perrhenate homologues is made. The described syntheses and materials may be used as novel starting materials for extended technetium research.
Synthesis and Reactivity of Discrete Europium(II) Hydride Complexes
Authors: Richardson Georgia M. , Evans Matthew J. , Rajeshkumar Thayalan , McCone Jordan A. J. , Cameron Scott A. , Maron Laurent , Jones Cameron , Anker Mathew D. 
Published: February 2024

AbstractThe bulky β‐diketiminate ligand frameworks [BDIDCHP]− and [BDIDipp/Ar]− (BDI=[HC{C(Me)2N‐Dipp/Ar}2]− (Dipp=2,6‐diisopropylphenyl (Dipp); Ar=2,6‐dicyclohexylphyenyl (DCHP) or 2,4,6‐tricyclohexylphyenyl (TCHP)) have been developed for the kinetic stabilisation of the first europium (II) hydride complexes, [(BDIDCHP)Eu(μ‐H)]2, [(BDIDipp/DCHP)Eu(μ‐H)]2 and [(BDIDipp/TCHP)Eu(μ‐H)]2, respectively. These complexes represent the first step beyond the current lanthanide(II) hydrides that are all based on ytterbium. Tuning the steric profile of β‐diketiminate ligands from a symmetrical to unsymmetrical disposition, enhanced solubility and stability in the solution–state. This provides the first opportunity to study the structure and bonding of these novel Eu(II) hydride complexes crystallographically, spectroscopically and computationally, with their preliminary reactivity investigated.
Boll distribution of cotton effected by varying potassium rates within different irrigation levels
Authors: Bumguardner Amee R. , Lewis Katie L. , Byrd Seth A. , Ritchie Glen L. , Morgan Gaylon D. 
Published: February 2024

AbstractCotton (Gossypium hirsutum L.) requires potassium (K) in large amounts for crop growth and development and is more sensitive to low K availability in soils than other agronomic crops. Low K concentrations within the plant may decrease the rate of photosynthesis, which will impact plant growth and development. Cotton yield potential has increased due to genetic improvements, which may have increased the quantity and rate at which cotton takes up K. This research aimed to determine the effect of K fertilizer rates within irrigation level on boll distribution and yield contribution from specific node zones. This study was conducted at New Deal, TX in 2016 and 2017. Muriate of potash (KCl) was applied using knife injection at rates of 0, 45, 90, 135, and 180 kg K h−1 with 80% and 30% evapotranspiration (ET) irrigation levels. Differences were not noted for estimated box mapping yield between K rates in 2016 (p = 0.3996). When 180 kg K ha−1 was applied, total bolls and estimated box mapping yield within 30% ET increased in the early and middle node zones and total nodes over all other K application rates in 2017. It was observed with box mapping that the early and middle node zones were able to utilize applied K more effectively due to the increase in bolls and yield compared to the late and vegetative node zones. Our results suggest that K is an important nutrient in cotton production due to the impacts it has on the early and middle node zones.
Do newer maize hybrids grow roots faster and deeper?
Authors: Sciarresi Cintia , Thies August , Topp Christopher , Eudy Douglas , Trifunovic Slobodan , Ruiz Alejo , Dixon Philip M. , Miguez Fernando , Burras Lee C. , Archontoulis Sotirios V. 
Published: February 2024

AbstractUnderstanding historical changes in root depth attributes is needed for crop productivity and sustainability assessments, but such information is rare. We explored whether newer maize (Zea mays L.) hybrids grow roots faster and deeper than older hybrids and quantified the role of management and environment on root trait expression. We measured root front velocity (RFV) and maximum root depth in 11 Bayer Crop Science legacy hybrids released from 1983 to 2017 across five environments in the US Corn Belt during 2021 and 2022. Root depth was measured weekly during vegetative stages with manual probes and the maximum root depth at crop harvest with a Giddings probe. Results indicated that the RFV and maximum root depth slightly increased with the year of hybrid release (0.13% per year, p = 0.1) at 8.7 plants m−2. Historical increases in plant density from 4.7 to 8.7 plants m−2 lowered RFV and maximum root depth, but the new hybrids compensated for this loss, resulting in 4% higher RFV and 3% higher maximum depth when comparing systems from 1983 to 2017. The environment strongly influenced root trait expression (>41%). Rain anomaly and soil bulk density explained a portion of this variation. We found a linear relationship between root depth and leaf number (R2 = 0.95) and a nonlinear relationship between RFV and maximum root depth (R2 = 0.77), which can stimulate crop model improvements. Faster and deeper roots were not correlated with maize yields in our environments. This study enhances our understanding of maize breeding impacts on root traits.
Penetrance interactions of colour pattern loci in the African Monarch and their implications for the evolution of dominance
Authors: ffrench‐Constant Richard H. , Bennie Jonathan , Gordon Ian J. , Depew Lorna , Smith David A. S. 
Published: February 2024

AbstractScoring the penetrance of heterozygotes in complex phenotypes, like colour pattern, is difficult and complicates the analysis of systems in which dominance is incomplete or evolving. The African Monarch (Danaus chrysippus) represents an example where colour pattern heterozygotes, formed in the contact zone between the different subspecies, show such intermediate dominance. Colour pattern in this aposematic butterfly is controlled by three loci A, B and C. The B and C loci are closely linked in a B/C supergene and significant interaction of B and C phenotypes is therefore expected via linkage alone. The A locus, however, is not linked to B/C and is found on a different chromosome. To study interactions between these loci we generated colour pattern heterozygotes by crossing males and females bearing different A and B/C genotypes, collected from different parts of Africa. We derived a novel scoring system for the expressivity of the heterozygotes and, as predicted, we found significant interactions between the genotypes of the closely linked B and C loci. Surprisingly, however, we also found highly significant interactions between C and the unlinked A locus, modifications that generally increased the resemblance of heterozygotes to homozygous ancestors. In contrast, we found no difference in the penetrance of any of the corresponding heterozygotes from crosses conducted either in allopatry or sympatry, in reciprocal crosses of males and females, or in the presence or absence of endosymbiont mediated male‐killing or its associated neoW mediated sex‐linkage of colour pattern. Together, this data supports the idea that the different colour morphs of the African Monarch meet transiently in the East African contact zone and that genetic modifiers act to mask inappropriate expression of colour patterns in the incorrect environments.
Mechanical soil disturbance in a pine savanna has multiyear effects on plant species composition
Authors: Dixon Cinnamon M. , Robertson Kevin M. , Reid Angela M. , Rother Monica T. 
Published: February 2024

AbstractSoil disturbance threatens native perennial grasslands and savannas worldwide, including pine savannas of the North American Coastal Plain. Disk harrows are used in the region to plow linear features for firebreaks to contain prescribed fires, to manage game and other wildlife, and to reduce wildfire hazard to protect forest resources. However, the long‐term response of vegetation to these disturbances has not been well investigated. Our aim was to compare vegetation changes over time (0–9 years) following repeated disturbance by disking and a single disturbance by disking for firebreaks with undisturbed vegetation within a native pine savanna. We hypothesized that (1) a single disking event has multiyear effects on plant species composition and abundance because of the loss of perennial, dispersal‐limited species, but that partial survival of propagules allows the recovery to be more complete than following repeated disturbance, and (2) post‐disturbance changes are determined by species' life‐history characteristics resulting in a successional trajectory toward the undisturbed community. We established 10 plots within a repeated‐disturbance firebreak and a single‐disturbance firebreak, and in undisturbed vegetation (n = 30). We identified plant species within the plots six times over nine years, categorized plant species by life span, seed bank persistence, and dispersal mechanism, and assessed changes in the plant community using ordination. Changes in species  composition in both repeated and single disturbance treatments showed a pattern consistent with succession toward the undisturbed plant community, but vegetation in neither disturbance treatment matched undisturbed treatment conditions within the nine years of study. Repeated‐disturbance plots progressed from a high occurrence of annuals to species with persistent seed banks and wind‐dispersed species. Single‐disturbance plots were more strongly associated with perennials, species lacking a persistent seed bank, and species dispersed by vertebrate consumption, but not to the same degree as undisturbed plots, although differences decreased slightly over time. Our results relating to narrow mechanical soil disturbances in pine savanna vegetation are consistent with studies concluding that similar but larger scale disturbances have long‐term degradational effects on the plant community. Therefore, conservation management plans should consider the possible negative long‐term effects of soil disturbance on native perennial herbaceous plant communities.
Dispersal synchronizes giant kelp forests
Authors: Wanner Miriam S. , Walter Jonathan A. , Reuman Daniel C. , Bell Tom W. , Castorani Max C. N. 
Published: February 2024

AbstractSpatial synchrony is the tendency for population fluctuations to be correlated among different locations. This phenomenon is a ubiquitous feature of population dynamics and is important for ecosystem stability, but several aspects of synchrony remain unresolved. In particular, the extent to which any particular mechanism, such as dispersal, contributes to observed synchrony in natural populations has been difficult to determine. To address this gap, we leveraged recent methodological improvements to determine how dispersal structures synchrony in giant kelp (Macrocystis pyrifera), a global marine foundation species that has served as a useful system for understanding synchrony. We quantified population synchrony and fecundity with satellite imagery across 11 years and 880 km of coastline in southern California, USA, and estimated propagule dispersal probabilities using a high‐resolution ocean circulation model. Using matrix regression models that control for the influence of geographic distance, resources (seawater nitrate), and disturbance (destructive waves), we discovered that dispersal was an important driver of synchrony. Our findings were robust to assumptions about propagule mortality during dispersal and consistent between two metrics of dispersal: (1) the individual probability of dispersal and (2) estimates of demographic connectivity that incorporate fecundity (the number of propagules dispersing). We also found that dispersal and environmental conditions resulted in geographic clusters with distinct patterns of synchrony. This study is among the few to statistically associate synchrony with dispersal in a natural population and the first to do so in a marine organism. The synchronizing effects of dispersal and environmental conditions on foundation species, such as giant kelp, likely have cascading effects on the spatial stability of biodiversity and ecosystem function.
Biocompatible Phosphorescent Ir(III) Complexes for Hypoxia Sensing in PLIM Mode
Authors: Samandarsangari Mozhgan , Zharskaia Nina A. , Silonov Sergey A. , Galenko Ekaterina E. , Karpitskaya Daria O. , Rück Angelika , Kritchenkov Ilya S. , Tunik Sergey P. 
Published: February 2024

AbstractIn this work, two new biscyclometalated Ir(III) complexes with diimine ligands were synthesized. The compounds were characterized by 1D and 2D NMR spectroscopy and HR ESI mass spectrometry. All complexes exhibit efficient phosphorescence with pronounced sensitivity to the presence of oxygen. The photophysical properties of the obtained compounds, including absorption, emission spectra, lifetimes and quantum yields of phosphorescence were measured in various aqueous and model biological media with variations in pH, temperature and at various O2 concentrations. The complexes exhibit a very good sensory response to the changes in oxygen concentration, resulting in an increase in quantum yields and lifetimes by 2.8–5.5 times upon oxygen removal from aerated aqueous solutions. Biological tests with CHO‐K1 cell line have shown that these compounds display low toxicity, rapid internalization into cells and localization predominantly in lysosomes. For the most promising complex the phosphorescence lifetime imaging experiments were conducted, revealing that this sensor markedly changes the phosphorescence lifetime values in cells from 1.8 to 4.1 μs upon transition from normoxia to simulated hypoxia. The obtained results indicate that this type of iridium chromophores can be effectively used for assessing the oxygen status of living objects by using time‐resolved luminescent microscopy.
Beyond the Limits of Perbromo‐Substituted Octahedral Pnictogenaboranes: A Spectroscopic and Computational Study
Authors: Keller Willi , Fanfrlík Jindřich , Hnyk Drahomír 
Published: February 2024

AbstractOctahedral closo‐1,2‐Pn2B4Br4 (Pn=P, As) molecules react with tetrahydrothiophene (THT), regarded as a soft base, much slower than with tetrahydrofuran (THF), considered a hard base. Namely, the reaction begins with only Pn=P at temperatures above 140 °C; 4‐Br(CH2)4S‐closo‐1,2‐P2B4Br3 has been detected as the first product resulting from the cleavage and insertion of a thiobutylate group into the B−Br bond. Unlike in the reaction with THF, the addition of a second THT moiety has not been observed. Conversely, also starting from 140 °C, conjuncto‐3,3’‐(1,2‐Pn2B4Br3)2 has been found as the final product of the reaction, which indicates the presence of 3‐Br(CH2)4S‐closo‐1,2‐P2B4Br3 as another intermediate during the conversion. A computational examination has revealed that it occurs through a pentagonal pyramidal stationary point as an additional intermediate, the latter of which serves as the crucial structural assembly for the thermal conversion that produces the conjuncto motif. Computations of the energy balance and 11B and 31P NMR chemical shifts are in agreement with experimental observations. This reaction is made possible by the presence of σ‐holes on the bromine atoms. In addition, the presence of the σ‐holes on the pnictogens has enabled ESI‐MS to detect various anions appearing during earlier and current syntheses.
Sensitive and rapid analysis of plasmid DNA topology isoforms by capillary gel electrophoresis with laser induced fluorescence in uncoated capillary
Authors: He Yan , Orlet John , Cunio Olivia , Thompson Lawrence , Jones Michael T 
Published: February 2024

AbstractThe work describes the use of SYBR Gold to improve the detection sensitivity of plasmid DNA topoisomers by capillary gel electrophoresis with laser induced fluorescence in an uncoated capillary. The impact of different dyes, including ethidium bromide, SYBR Green and SYBR Gold, was compared based on detection and separation of DNA plasmid topoisomers. Use of SYBR Gold enabled improvement of detection sensitivity by 15‐fold while maintaining good separation resolution of the different topoisomers. The baseline dropped with the use SYBR Gold but was overcome by the employment of a capillary with longer ineffective length (40 vs. 20 cm). Separation resolution and reproducibility were impacted by the concentration of SYBR Gold and hydroxypropyl methylcellulose. With the use of a short capillary (10 cm effective length and 50 cm total length), fast separations of supercoiled, linear, open circular, and other isoforms were accomplished within 8 min. Appropriate capillary cleaning with 0.1 M sodium hydroxide/0.1 M hydrochloric acid and capillary storage with 0.1 M hydrochloric acid ensured good separation reproducibility of 217 runs during an extended period of use.
Thermal performance of solar flat plate collector using energy storage phase change materials
Authors: Babu Dinesh , Shukla Anuj Kumar , Gaba Vivek Kumar , Dewan Anupam 
Published: February 2024

AbstractThe present study has been carried out to improve the overall efficiency of a conventional flat plate solar collector (FPSC) using two different heat storage phase change materials (PCMs). Two grades of paraffin wax—Paraffin‐P116 (PCM‐1) and Paraffin‐5838 (PCM‐2) as PCM are selected for the analysis based on their high heat fusion rate, low thermal conductivity, and suitable phase transition temperature. The present code has been validated with experimental results and it showed a maximum error of 6.43% in predicting the water outlet temperature. Absorber plate temperature, useful heat transfer rate, water outlet temperature and efficiencies are estimated to improve the performance of FPSC with and without PCM for various flow rates (15 lph and 30 lph) with two different weights of PCM (9 kg and 14 kg) for three different locations in India, [Chennai (13.0827° N, 80.2707° E), Bengaluru (12.9716° N, 77.5946° E), and Delhi (28.7041° N, 77.1025° E)]. The maximum increment in the efficiency of FPSC with the use of PCM‐1 is 19.59% and with the use of PCM‐2 is 16.53%. Using 14 kg of PCM‐1 with the conventional FPSC at water inlet flow rate of 15 lph increases the overall thermal efficiency up to 19.59% compared with conventional FPSC. The maximum increase in the percentage of efficiency with PCM‐1 from conventional FPSC for different cases of 15 lph‐09 kg is 16.34%, 15 lph‐14 kg is 19.59%, 30 lph‐09 kg is 14.57% and 30 lph‐14 kg is 18.45%. From the present study, it can be concluded that the overall efficiency of FPSC is increased with the use of 14 kg of PCM‐1 with conventional FPSC at the inlet water flow rate of 15 lph.
Identifying and Predicting Delayed Mortality with Toxicokinetic–Toxicodynamic Models
Authors: Jager Tjalling 
Published: February 2024

Abstract
The prevalence of standardized toxicity testing in ecotoxicology has largely obscured the notion that toxicity is a function of time as well. The necessity of considering time is vividly demonstrated by observations of delayed mortality, that is, deaths continue to occur even when animals are no longer exposed to a toxicant. In this contribution, I explore to what extent toxicokinetic–toxicodynamic (TKTD) models from the framework of the General Unified Threshold model for Survival (GUTS) can capture delayed mortality, and to what extent this phenomenon can be predicted from short-term standard tests. I use a previously published data set for fluoroquinolones in Daphnia magna that shows strongly delayed mortality (using immobilization as a proxy for death). The model analysis shows that the GUTS stochastic death models can capture delayed mortality in the complete data set with a long recovery phase, but that the delayed effects would not have been predicted from a 2-day standard test. The study underlines the limited information content of standard acute test designs. Toxicokinetic–toxicodynamic modeling offers a handle on the time aspects of toxicity but cannot always be relied on to provide accurate extrapolations based on severely limited standard tests. The phenomenon of delayed toxicity requires more structured study to clarify its prevalence and impact; I discuss several avenues for further investigation. Environ Toxicol Chem 2024;43:1030–1035. © 2024 SETAC.
Liquidity‐adjusted value‐at‐risk using extreme value theory and copula approach
Authors: Kamal Harish , Paul Samit 
Published: February 2024

AbstractIn this study, we propose the application of the GARCH‐EVT‐Copula model in estimating liquidity‐adjusted value‐at‐risk (L‐VaR) of energy stocks while modeling nonlinear dependence between return and bid‐ask spread. Using the L‐VaR framework of Bangia et al. (1998), we present a more parsimonious model that effectively captures non‐zero skewness, excess kurtosis, and volatility clustering of both return and spread distributions of energy stocks. Moreover, to measure the nonlinear dependence between return and spread series, we use multiple copulas: Clayton, Gumbel, Frank, Normal, and Student‐t. Based on the statistical backtesting and economic loss functions, our results suggest that the GARCH‐EVT‐Clayton copula is superior and most consistent in forecasting L‐VaR compared with other competing models. This finding has several implications for investors, market makers, and daily traders who appreciate the importance of liquidity in market risk computation.