bluuebunny/crossref_metadata_2025 huggingface dataset:
VAMP1-Related Congenital Myasthenic Syndrome: A Case Report and Literature Review
Authors: Yıldırım Miraç , Yarenci Gülçin Bilicen , Genç Mustafa Berk , Uçar Çiğdem İlter , Bayav Secahattin , Tekin Merve Nur , Bektaş Ömer , Teber Serap
Published: March 2024

Congenital myasthenic syndrome-25 (CMS-25) is an autosomal recessive neuromuscular disorder caused by a homozygous mutation in VAMP1 gene. To date, only eight types of allelic variants in VAMP1 gene have been reported in 12 cases of CMS-25. Here, we report on an 8-year-old boy with motor developmental delay, axial hypotonia, myopathic face, muscle weakness, strabismus, ptosis, pectus carinatum, kyphoscoliosis, joint contractures, joint laxity, seizures, and recurrent nephrolithiasis. He also had feeding difficulties and recurrent aspiration pneumonia. Brain magnetic resonance imaging at 20 months of age showed left focal cerebellar hypoplasia. Genetic analysis revealed a homozygous missense variant of c.202C > T (p.Arg68Ter) in the VAMP1 gene. Treatment with oral pyridostigmine was started, which resulted in mild improvement in muscle strength. Salbutamol syrup was added a few months later, but no significant improvement was observed. This case report presents novel findings such as focal cerebellar hypoplasia and nephrolithiasis in VAMP1-related CMS-25. Consequently, this case report extends the clinical spectrum. Further studies are needed to expand the genotype–phenotype correlations in VAMP1-related CMS-25.
A Crossover Trial Evaluating Coconut Oil as an Alternative to Commercial Ultrasound Gel in Obstetrical Ultrasounds
Authors: Edelman Claire , Rouse Caroline , Yang Ziyi , Cook Myanna , Daggy Joanne , Shanks Anthony
Published: March 2024

Objective Our objective was to evaluate the quality of obstetrical ultrasound images obtained with coconut oil compared with commercial ultrasound gel and to assess patient acceptability.

Study Design This was a randomized two-period crossover study in which 40 pregnant patients had standard biometry images obtained with both coconut oil and commercial ultrasound gel during their growth or anatomy ultrasound. All images were then rated by two blinded maternal–fetal medicine physicians on quality, resolution, and detail using a 0 to 100 scale. Contrasts obtained from linear mixed models were used to estimate the differences in image parameters between the agents. Participant experience was evaluated with an acceptability survey which included five items measured on a five-point Likert scale.

Results Image quality, as rated by physicians, was found to be equivalent between commercial ultrasound gel and coconut oil. Additionally, there was not a statistically significant difference in image resolution or detail between the two coupling agents. The overall patient experience was significantly lower for commercial ultrasound gel when compared with coconut oil (mean difference = − 5.48, 95% confidence interval = [−6.89, −4.06]).

Conclusion Ultrasound images collected with coconut oil as the coupling agent are equivalent in quality to those collected using commercial ultrasound gel. Patients also preferred the use of coconut oil during their ultrasound, making its use a possible way to improve the patient ultrasound experience. Coconut oil has the potential as an alternative coupling agent that could significantly increase access to ultrasound use in resource-limited settings.

Key Points
Conceptual awareness levels of digital logistics among Turkish university students
Authors: Emre Adem , Somuncu Seher , Korkmaz Meltem , Demirci Ebru
Published: March 2024

The logistics industry has witnessed the emergence of digital technology as a central topic of discourse, and terminology associated with digital logistics has gained extensive usage among professionals in the transportation, logistics, and international trade sectors. Digital logistics is highly dependent on the accumulation of data from the logistical activities conducted by organizations. The implementation of a digitalized process presents organizations with novel prospects, such as decreased operational expenses, increased efficiency, and reduced uncertainties associated with order fulfillment. Additionally, digital logistics facilitates the enhancement of distribution methods for businesses. The post-graduation knowledge levels of students become significant factors for potential employers. University education plays a crucial role in imparting academic and technical expertize in the domain of logistics; therefore, it is critical that logistics programs integrate a greater number of digital courses. Academic institutions play a pivotal role in enabling students to gain consciousness and comprehension of emerging patterns and concepts. In light of this, the purpose of this research was to determine “the extent of digital logistics and digitalization conceptual awareness” among university students. The results of the study will be used as a guide for educational institutions like colleges to follow when it comes to incorporating digital courses into their curriculum. It was decided to use questionnaires for the purpose of data collecting. A statistical analysis was conducted on the information gathered from the university students. While most students had a good grasp of the concepts of AI, VR, digital supply chain, and transportation management systems, female students showed less familiarity with these phrases than their male counterparts. It is possible for universities to provide students with the opportunity to acquire knowledge of digital logistics concepts through the implementation of training courses, workshops, programs, and term projects. It is advisable to promote students’ acquisition of knowledge regarding digital technologies through the implementation of additional courses. The educational experience and students’ overall level of awareness can be greatly enhanced through partnerships between IT firms and institutions.
Structural studies of amorphous polymer films: Experiment and calculation
Authors: Hurova D. E. , Geidarov V. G. , Braude I. S. , Aksenova N. A. , Stepanian S. G. , Adamowicz L. , Galtsov N. N.
Published: March 2024

To analyze X-ray diffraction patterns obtained from polyimide films subjected to external influence (uniaxial tension and exposure at liquid helium temperature), radial distribution function (RDF) curves were constructed and the geometry of the 4,4′-oxydiphenylene-pyromellitimide monomer (PM) was calculated. From the RDF analysis, it follows that uniaxial tension of PM polymer films leads to a change in the geometry of the monomer, and exposure at low temperatures leads to mutual ordering of the polymer chains.
High-energy-resolution off-resonant spectroscopy with self-seeded x-ray free-electron laser pulses
Authors: Sohn Jang Hyeob , Kang Gyeongbo , Choi Tae-Kyu , Lee Gyusang , Lee Changhoo , Chun Sae Hwan , Park Jaeku , Shin Dongbin , Cho Byoung-Ick
Published: March 2024

This paper presents the implementation of high-energy-resolution off-resonant spectroscopy (HEROS) measurements using self-seeded x-ray free-electron laser (XFEL) pulses. This study systematically investigated XFEL conditions, including photon energy and accumulated shot numbers, to optimize the measurement efficiency for copper foil samples near the K-edge. The x-ray absorption spectra reconstructed using HEROS were compared with those derived from fluorescence-yield measurements. The HEROS-based spectra exhibited consistent line shapes independent of the sample thickness. The potential application of HEROS to high-temperature copper was also explored. HEROS offers distinct advantages including scan-free measurement of x-ray absorption spectra with reduced core-hole lifetime broadening and self-absorption effects. Using self-seeded XFEL pulses, HEROS facilitates single-shot-based pump–probe measurements to investigate the ultrafast dynamics in various materials and diverse conditions.
The importance of the inertial coupling in the two-fluid model of two-phase flow
Authors: Clausse Alejandro , López-de-Bertodano Martín
Published: March 2024

The new flux representation of the two-fluid model of two-phase flow, where the mixture is described in terms of the volumetric and drift fluxes, is currently the most consistent formulation to treat the inertial coupling between phases. In this representation, the dynamics of the relative motion between phases is revealed as a non-linear wave propagation equation. It is shown that the character and stability of this equation is determined by the balance between the inertial coupling and the interfacial drag. A novel stability criterion is derived that can be used to assess the interfacial closure laws and as a tool to determine the conditions under which a drift-flux correlation is stable. A family of inertial coupling functions for vertical two-phase flow, based on topologies of bubble's vortical wakes, is derived and the corresponding coupling parameters are assessed using available experimental data. The resulting stability maps reveal the occurrence of an unstable region at intermediate void fractions bound by a bistable condition at low and high void fractions, which can be associated with the slug flow-pattern regime.
Hemodynamics in left coronary artery with ramus intermedius: A patient-specific computational study
Authors: Singhal Mudrika , Gupta Raghvendra , Saikia Bishwajeet , Malviya Amit , Sarma Amitav , Phukan Pranjal , Lynser Donboklang
Published: March 2024

Clinical studies based on coronary computed tomography angiography (CCTA) images suggest that the presence of ramus intermedius (RI) in the left coronary artery (LCA) may aggravate the atherosclerotic depositions in the furcation region. In this study, computational fluid dynamics simulations are performed in patient-specific coronary models consisting of bifurcating LCA and two models having trifurcating LCA. Three-dimensional patient-specific coronary models are constructed from CCTA images obtained from North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India. Results indicate that the flow redistribution happens in the left coronary branch due to the presence of RI and the flow to left anterior descending artery (LAD) is reduced significantly. Recirculation and flow separation regions are observed in the proximal parts of the LAD and left circumflex artery for trifurcation geometries. The qualitative and quantitative analysis of wall shear stress-based descriptors suggests that the presence of the intermediate branch may affect the atherosusceptibility of the proximal region of LAD. The study indicates that the presence of RI may act as a contributing factor for plaque development and progression in the furcation region and proximal parts of LAD.
Planar defects in α-Ga2O3 thin films produced by HVPE
Authors: Myasoedov A. V. , Pavlov I. S. , Pechnikov A. I. , Stepanov S. I. , Nikolaev V. I.
Published: March 2024

The defect structure of α-phase gallium oxide thin films was investigated using transmission electron microscopy (TEM). Epitaxial Ga2O3 films were grown via halide vapor-phase epitaxy on c-plane sapphire substrates. TEM analysis revealed a high density of extended planar defects within the films, primarily located along prismatic planes of {112¯0} type. Displacement vectors were determined using the invisibility criterion for stacking faults. The study encompassed both planar and cross-sectional views of the films. It is hypothesized that these defects form due to the motion of edge partial dislocations with the 13⟨11¯00⟩ Burgers vector. Various mechanisms of their formation have been explored.
Research of turbulent transport due to dissipative trapped electron mode in tokamak plasmas
Authors: Toda S. , Nunami M. , Kasuya N.
Published: March 2024

The purpose of this article is to study turbulent transport for laboratory plasmas in toroidal devices by gyrokinetic analyses. Linear analysis is performed to clarify the dominant mode for tokamak plasmas. The dissipative trapped electron mode (d-TEM) and the ion temperature gradient (ITG) mode are predicted using the Sugama collision model operator [Sugama et al., Phys. Plasmas 16, 112503 (2009)]. Nonlinear gyrokinetic analysis is used to quantify turbulent transport. The nonlinear simulation results show the levels of particle and energy transport, where the d-TEM and ITG mode are unstable. The effect of zonal flows is studied by the linear and nonlinear simulation results. The results of the analysis are compared when two types of model collision operator, which are the Sugama and Lenard–Bernstein [Phys. Rev. 112, 1456 (1958)] collision model operators, are used. In this study, the simulation results using the Sugama collision operator show a stronger effect of the zonal flows on the turbulent transport than those using the Lenard–Bernstein collision operator, as predicted by the linear simulation result such as the zonal flow decay time.
Effect of polyacid architecture and polycation molecular weight on lateral diffusion within multilayer films
Authors: Brito Jordan , Shah Parin Purvin , Aliakseyeu Aliaksei , Sukhishvili Svetlana A.
Published: March 2024

Despite the potential use of polyelectrolyte multilayers for biomedical, separation, and energy applications, their dynamic properties are not sufficiently understood. In this work, center-of-mass diffusion of a weak polyacid—poly(methacrylic acid) (PMAA) of linear and 8-arm architecture (L-PMAA and 8-PMAA, respectively) and matched molecular weight—was studied in layer-by-layer (LbL) assemblies with poly(diallyldimethylammonium) chloride (PDADMAC) of varied molecular weight. The film deposition at low-salt, acidic conditions when PMAA was only partially ionized yielded thicker, more diffused layers with shorter PDADMAC chains, and bilayer thickness decreased for multilayers constructed with longer PDADMAC. The molecular architecture of PMAA had a weak effect on film growth, with bilayer thickness being ∼20% larger for L-PMAA for the films constructed with the shortest PDADMAC (35 kDa) and identical film growth for L-PMAA and 8-PMAA with the longest PDADMAC (300 kDa). The exposure of the multilayer films to 0.2M NaCl triggered a reduction in PMAA ionization and significant lateral diffusivity of fluorescently labeled PMAA molecules (PMAA*), with diffusion coefficients D ranging from 10−13 to 10−12 cm2/s, as determined by the fluorescence recovery after photobleaching technique. For all the films, polymer mobility was higher for star polyacids as compared to their linear counterparts, and the dependence of PMAA diffusion coefficient D on PDADMAC molecular weight (D ∼ M−n) was relatively weak (n < 0.6). However, 8-PMAA demonstrated an approximately doubled power exponent compared to the L-PMAA chains, suggesting a stronger effect of the molecular connectivity of the partner polycation molecules on the diffusion of star polyelectrolytes.
Numerical investigation of the mechanical properties of lattice structures inspired from polycrystalline materials
Authors: Liu Yabo , Bai Guangwei , Qu Zhipeng , Xu Xiaochang
Published: March 2024

In this work, polycrystalline-like lattice structures that are inspired by the geometry of polycrystalline materials are designed. They are generated by filling periodic lattice structures into a Voronoi diagram. Then, finite element analyses of two periodic and eight polycrystalline-like lattice structures are performed to compare their mechanical properties. The numerical results show that polycrystalline-like lattice structures consisting of anisotropic rectangular X-type periodic unit cells are isotropic at the macroscale. Moreover, they have a higher specific stiffness and specific strength than periodic lattice structures under compression. Then, the energy absorption capability is investigated. Five energy absorption indicators (energy absorption, energy absorption per unit volume, specific energy absorption per unit mass, crush stress efficiency, and plateau stress) reveal that polycrystalline-like lattice structures are better energy absorption structures. Furthermore, the defect sensitivity of missing struts is discussed. The findings of this work offer a new route for designing novel lattice structures.
Wall effect on single bubble rising in a Hele–Shaw cell
Authors: Jian Zhen , Xiang Shiping , Li Ruixuan , Jiang Zhen , Qin Lang , Zhang Xurui
Published: March 2024

Single air bubble rising near vertical wall in a Hele–Shaw cell was investigated experimentally. Bubbles with a large range of size from 4.46 mm to 21.68 mm were generated. A vertical wall was introduced in the cell, and the initial distance between the wall and the bubble releasing position was varied systematically to study the wall effect on the rising dynamics. Rising trajectory, bubble morphology, and rising characteristics were analyzed. Bubble will migrates away from the wall, and the trajectory transits from rectilinear path to zigzag. Two mechanisms of zigzag were revealed as “rigid zigzag” for the small bubble and “contracting zigzag” for the large bubble. It is always easier to zigzag for a more rounded bubble, and migration is always stronger with a smaller normalized initial distance.
Development of analytic gradients for the Huzinaga quantum embedding method and its applications to large-scale hybrid and double hybrid DFT forces
Authors: Csóka József , Hégely Bence , Nagy Péter R. , Kállay Mihály
Published: March 2024

The theory of analytic gradients is presented for the projector-based density functional theory (DFT) embedding approach utilizing the Huzinaga-equation. The advantages of the Huzinaga-equation-based formulation are demonstrated. In particular, it is shown that the projector employed does not appear in the Lagrangian, and the potential risk of numerical problems is avoided at the evaluation of the gradients. The efficient implementation of the analytic gradient theory is presented for approaches where hybrid DFT, second-order Møller–Plesset perturbation theory, or double hybrid DFT are embedded in lower-level DFT environments. To demonstrate the applicability of the method and to gain insight into its accuracy, it is applied to equilibrium geometry optimizations, transition state searches, and potential energy surface scans. Our results show that bond lengths and angles converge rapidly with the size of the embedded system. While providing structural parameters close to high-level quality for the embedded atoms, the embedding approach has the potential to relax the coordinates of the environment as well. Our demonstrations on a 171-atom zeolite and a 570-atom protein system show that the Huzinaga-equation-based embedding can accelerate (double) hybrid gradient computations by an order of magnitude with sufficient active regions and enables affordable force evaluations or geometry optimizations for molecules of hundreds of atoms.
Integrability, breather, rogue wave, lump, lump-multi-stripe, and lump-multi-soliton solutions of a (3 + 1)-dimensional nonlinear evolution equation
Authors: Mandal Uttam Kumar , Das Amiya , Ma Wen-Xiu
Published: March 2024

In this article, we consider a new (3 + 1)-dimensional evolution equation, which can be used to interpret the propagation of nonlinear waves in the oceans and seas. We effectively investigate the integrable properties of the considered nonlinear evolution equation through several aspects. First of all, we present some elementary properties of multi-dimensional Bell polynomial theory and its relation with Hirota bilinear form. Utilizing those relations, we derive a Hirota bilinear form and a bilinear Bäcklund transformation. By employing the Cole–Hopf transformation in the bilinear Bäcklund transformation, we present a Lax pair. Additionally, using the Bell polynomial theory, we compute an infinite number of conservation laws. Moreover, we obtain one-, two-, and three-soliton solutions explicitly from Hirota bilinear form and illustrate them graphically. Breather solutions are also derived by employing appropriate complex conjugate parameters in the two-soliton solution. Choosing the generalized algorithm for rogue waves derived from the N-soliton solution, we directly obtain a first-order center-controllable rogue wave. Lump solutions are formulated by employing a well-established quadratic test function as a solution to the Hirota bilinear form. Further taking the test function in a combined form of quadratic and exponential functions, we obtain lump-multi-stripe solutions. Furthermore, a combined form of quadratic and hyperbolic cosine functions produces lump-multi-soliton solutions. The fission and fusion effects in the evolution of lump-multi-stripe solutions and lump-soliton-solutions are demonstrated pictorially.
Revisiting the benzene excimer using [2,2] paracyclophane model system: Experiment and theory
Authors: Haggag Omer , Baer Roi , Ruhman Sanford , Krylov Anna I.
Published: March 2024

We report high-level calculations of the excited states of [2,2]-paracyclophane (PCP), which was recently investigated experimentally by ultrafast pump–probe experiments on oriented single crystals [Haggag et al., ChemPhotoChem 6 e202200181 (2022)]. PCP, in which the orientation of the two benzene rings and their range of motion are constrained, serves as a model for studying benzene excimer formation. The character of the excimer state and the state responsible for the brightest transition are similar to those of the benzene dimer. The constrained structure of PCP allows one to focus on the most important degree of freedom, the inter-ring distance. The calculations explain the main features of the transient absorption spectral evolution. This brightest transition of the excimer is polarized along the inter-fragment axis. The absorption of the light polarized in the plane of the rings reveals the presence of other absorbing states of Rydberg character, with much weaker intensities. We also report new transient absorption data obtained by a broadband 8 fs pump, which time-resolve strong modulations of the excimer absorption. The combination of theory and experiment provides a detailed picture of the evolution of the electronic structure of the PCP excimer in the course of a single molecular vibration.
Spin–orbit torque reconfigurable diffraction gratings
Authors: Huang Xiaolin , Xu Zitian , Liang Jiayang , Wu Biao , Jiang Siyuan , Gao Nan
Published: March 2024

Spin–orbit torque (SOT) provides a convenient, fast, and efficient way to switch the magnetization and has been applied in memory, logic, and microwave devices. Here, we report the application of SOT in the spatial modulation of the optical field. We construct a diffraction grating composed of perpendicularly magnetized current channels that can be switched using the SOT current pulses, and the resulting periodic magnetization patterns are transferred into the polarization modulation of light through the magneto-optical effect. We demonstrate that the periodic structures and diffraction peaks of the grating can be reconfigured electrically. These results would open up an avenue to the application of the state-of-the-art spintronic technologies in fast tunable diffractive optics.
Phonon-mediated ultrafast energy- and momentum-resolved hole dynamics in monolayer black phosphorus
Authors: Gao Siyuan , Wang Yu-Chen , Zhao Yi
Published: March 2024

The electron–phonon scattering plays a crucial role in determining the electronic, transport, optical, and thermal properties of materials. Here, we employ a non-Markovian stochastic Schrödinger equation (NMSSE) in momentum space, together with ab initio calculations for energy bands and electron–phonon interactions, to reveal the phonon-mediated ultrafast hole relaxation dynamics in the valence bands of monolayer black phosphorus. Our numerical simulations show that the hole can initially remain in the high-energy valence bands for more than 100 fs due to the weak interband scatterings, and its energy relaxation follows single-exponential decay toward the valence band maximum after scattering into low-energy valence bands. The total relaxation time of holes is much longer than that of electrons in the conduction band. This suggests that harnessing the excess energy of holes may be more effective than that of electrons. Compared to the semiclassical Boltzmann equation based on a hopping model, the NMSSE highlights the persistence of quantum coherence for a long time, which significantly impacts the relaxation dynamics. These findings complement the understanding of hot carrier relaxation dynamics in two-dimensional materials and may offer novel insights into harnessing hole energy in photocatalysis.
Theoretical estimation of sonochemical characteristics in a single cavitation bubble under various static pressure conditions
Authors: Lv Liang , Lou Zongyong , Wan Changdong
Published: March 2024

Cavitation bubbles can be generated by introducing ultrasonic waves into the liquid. The growth and collapse of the bubbles transfer energy from ultrasonic waves to the gas mixture, resulting in the formation of an extreme environment with local high pressure and temperature, and then, multiple products (H2, ·OH, H·, O, H2O2, and so on) are produced. In the present study, the sonochemical characteristics inside an oxygen bubble have been investigated by using single bubble dynamics equations taking mass transfer, heat exchange, and chemical reactions into account. The effects of the equilibrium radius and static pressure on the temperature and the yields of H2, ·OH, and total oxidants inside the bubble are analyzed. There are optimal equilibrium radii that maximize gas temperature and the amounts of H2, ·OH, and total oxidants under different static pressures. The results of this paper are in good agreement with the previous results and can be used to explain sonochemical phenomena observed in experiments.
SoCal EcoServe: an online mapping tool to estimate wildfire impacts in southern California
Authors: Underwood Emma C. , Schrader-Patton Charlie C. , Hollander Allan D.
Published: March 2024

Background Wildfires in Mediterranean-type climate regions have numerous impacts on the ecosystem services provided by native shrublands, however, quantifying these impacts is challenging. Aims We developed a reproducible method to quantify fire impacts on ecosystem services and created a tool for resource managers in southern California. Methods The SoCal EcoServe tool consists of two components: a desktop tool and an online mapping tool. We used the Alisal Fire of 2021 as a case study and quantified: aboveground live carbon storage using pre- and post-fire biomass data; water runoff, groundwater recharge and sediment erosion retention by integrating data on burn severity into hydrological and sediment erosion models; and estimated recreation services and biodiversity using pre-fire data. Key results We estimated the Alisal Fire resulted in an immediate post-fire reduction in carbon storage of 25%, of which 20% was estimated to be permanently lost. Water runoff increased by 21%, groundwater recharge 7-fold, and sediment erosion increased 24-fold. Conclusions The EcoServe tool provides an initial approximation of wildfire impacts that can support damage assessments post-fire, track carbon storage and help identify priorities for post-fire restoration. Implications We intend the tool to be used by USDA Forest Service resource managers of shurblands in southern California. However, it can provide the framework for future work in shrublands throughout the western USA.
Signal integration in chemoreceptor complexes
Authors: Koler Moriah , Parkinson John S. , Vaknin Ady
Published: March 2024

Motile bacteria use large receptor arrays to detect chemical and physical stimuli in their environment, process this complex information, and accordingly bias their swimming in a direction they deem favorable. The chemoreceptor molecules form tripod-like trimers of receptor dimers through direct contacts between their cytoplasmic tips. A pair of trimers, together with a dedicated kinase enzyme, form a core signaling complex. Hundreds of core complexes network to form extended arrays. While considerable progress has been made in revealing the hierarchical structure of the array, the molecular properties underlying signal processing in these structures remain largely unclear. Here we analyzed the signaling properties of nonnetworked core complexes in live cells by following both conformational and kinase control responses to attractant stimuli and to output-biasing lesions at various locations in the receptor molecule. Contrary to the prevailing view that individual receptors are binary two-state devices, we demonstrate that conformational coupling between the ligand binding and the kinase-control receptor domains is, in fact, only moderate. In addition, we demonstrate communication between neighboring receptors through their trimer-contact domains that biases them to adopt similar signaling states. Taken together, these data suggest a view of signaling in receptor trimers that allows significant signal integration to occur within individual core complexes.
Structural and mechanistic basis of the central energy-converting methyltransferase complex of methanogenesis
Authors: Aziz Iram , Kayastha Kanwal , Kaltwasser Susann , Vonck Janet , Welsch Sonja , Murphy Bonnie J. , Kahnt Jörg , Wu Di , Wagner Tristan , Shima Seigo , Ermler Ulrich
Published: March 2024

Methanogenic archaea inhabiting anaerobic environments play a crucial role in the global biogeochemical material cycle. The most universal electrogenic reaction of their methane-producing energy metabolism is catalyzed by
N    
5
-methyl-tetrahydromethanopterin: coenzyme M methyltransferase (MtrABCDEFGH), which couples the vectorial Na
+
transport with a methyl transfer between the one-carbon carriers tetrahydromethanopterin and coenzyme M via a vitamin B
12
derivative (cobamide) as prosthetic group. We present the 2.08 Å cryo-EM structure of Mtr(ABCDEFG)
3
composed of the central Mtr(ABFG)
3
stalk symmetrically flanked by three membrane-spanning MtrCDE globes. Tetraether glycolipids visible in the map fill gaps inside the multisubunit complex. Putative coenzyme M and Na
+
were identified inside or in a side-pocket of a cytoplasmic cavity formed within MtrCDE. Its bottom marks the gate of the transmembrane pore occluded in the cryo-EM map. By integrating Alphafold2 information, functionally competent MtrA–MtrH and MtrA–MtrCDE subcomplexes could be modeled and thus the methyl-tetrahydromethanopterin demethylation and coenzyme M methylation half-reactions structurally described. Methyl-transfer-driven Na
+
transport is proposed to be based on a strong and weak complex between MtrCDE and MtrA carrying vitamin B
12
, the latter being placed at the entrance of the cytoplasmic MtrCDE cavity. Hypothetically, strongly attached methyl-cob(III)amide (His-on) carrying MtrA induces an inward-facing conformation, Na
+
flux into the membrane protein center and finally coenzyme M methylation while the generated loosely attached (or detached) MtrA carrying cob(I)amide (His-off) induces an outward-facing conformation and an extracellular Na
+
outflux. Methyl-cob(III)amide (His-on) is regenerated in the distant active site of the methyl-tetrahydromethanopterin binding MtrH implicating a large-scale shuttling movement of the vitamin B
12
-carrying domain.
Autophagy maintains endosperm quality during seed storage to preserve germination ability in
Arabidopsis
Authors: Shinozaki Daiki , Takayama Erina , Kawakami Naoto , Yoshimoto Kohki
Published: March 2024

To preserve germination ability, plant seeds must be protected from environmental stresses during the storage period. Here, we demonstrate that autophagy, an intracellular degradation system, maintains seed germination ability in
Arabidopsis thaliana
. The germination ability of long-term (>5 years) stored dry seeds of autophagy-defective (
atg
) mutant and wild-type (WT) plants was compared. Long-term stored (old) seeds of
atg
mutants showed lower germination ability than WT seeds, although short-term stored (new) seeds of
atg
mutants did not show such a phenotype. After removal of the seed coat and endosperm from old
atg
mutant seeds, the embryos developed into seedlings. Autophagic flux was maintained in endosperm cells during the storage period, and autophagy defect resulted in the accumulation of oxidized proteins and accelerated endosperm cell death. Consistent with these findings, the transcripts of genes,
ENDO-β-MANNANASE 7
and
EXPANSIN 2
, which are responsible for degradation/remodeling of the endosperm cell wall during germination, were reduced in old
atg
mutant seeds. We conclude that autophagy maintains endosperm quality during seed storage by suppressing aging-dependent oxidative damage and cell death, which allows the endosperm to perform optimal functions during germination, i.e., cell wall degradation/remodeling, even after long-term storage.
Neofunctionalization of an
OMT
cluster dominates polymethoxyflavone biosynthesis associated with the domestication of citrus
Authors: Peng Zhaoxin , Song Lizhi , Chen Minghua , Liu Zeyang , Yuan Ziyu , Wen Huan , Zhang Haipeng , Huang Yue , Peng Zhaowen , Yang Hongbin , Li Gu , Zhang Huixian , Hu Zhehui , Li Wenyun , Wang Xia , Larkin Robert M. , Deng Xiuxin , Xu Qiang , Chen Jiajing , Xu Juan
Published: March 2024

Polymethoxyflavones (PMFs) are a class of abundant specialized metabolites with remarkable anticancer properties in citrus. Multiple methoxy groups in PMFs are derived from methylation modification catalyzed by a series of hydroxylases and
O
-methyltransferases (OMTs). However, the specific
OMTs
that catalyze the systematic
O
-methylation of hydroxyflavones remain largely unknown. Here, we report that PMFs are highly accumulated in wild mandarins and mandarin-derived accessions, while undetectable in early-diverging citrus species and related species. Our results demonstrated that three homologous genes,
CreOMT3
,
CreOMT4
, and
CreOMT5
, are crucial for PMF biosynthesis in citrus, and their encoded methyltransferases exhibit multisite
O
-methylation activities for hydroxyflavones, producing seven PMFs in vitro and in vivo. Comparative genomic and syntenic analyses indicated that the tandem
CreOMT3
,
CreOMT4
, and
CreOMT5
may be duplicated from
CreOMT6
and contributes to the genetic basis of PMF biosynthesis in the mandarin group through neofunctionalization. We also demonstrated that N17 in CreOMT4 is an essential amino acid residue for C3-, C5-, C6-, and C3′-
O
-methylation activity and provided a rationale for the functional deficiency of OMT6 to produce PMFs in early-diverging citrus and some domesticated citrus species. A 1,041-bp deletion in the
CreOMT4
promoter, which is found in most modern cultivated mandarins, has reduced the PMF content relative to that in wild and early-admixture mandarins. This study provides a framework for reconstructing PMF biosynthetic pathways, which may facilitate the breeding of citrus fruits with enhanced health benefits.
Is animation always better for learning Chinese characters?
Authors: Yang Juan , Peng Rui
Published: March 2024

The present study investigated the effect of animations on Chinese character learning in multimedia presentations. In particular, we examined whether animations focusing on different knowledge of characters would yield different performance among students learning Chinese characters. The role of the animations which focused on the etymology of Chinese characters was tested in Experiment 1 with twelve English secondary school students. The results found that etymological animations were superior to flashcards for learners in recognizing forms of Chinese characters but not for understanding their meanings. In Experiment 2, the effect of animations which focused on demonstrating stroke order along with the audio explanations and on-screen written texts was addressed with 60 Thai secondary school students. The results revealed that animations demonstrating stroke order did not provide learners with advantages in orthographic learning. However, the findings support the redundant principle that static imagery and spoken and written text together facilitated character learning. In addition, the study showed that the students’ pace and flexibility of learning, the level of character difficulty, and students’ active processing have significant roles in character learning performance in a multimedia settings. This study provides implications for the design of multimedia instruction in foreign language acquisition and sheds light on the theoretical assumptions of dual-coding theory regarding learners’ cognitive loads in multimedia processing.
Reconsidering linguistic nativism from an interdisciplinary, emergentist perspective
Authors: Breyl Michael
Published: March 2024

For decades, interdisciplinary research efforts have accumulated insights that diminish the significance of the
classic nature versus nurture dichotomy, instead calling for a nuanced, multifactorial approach to ontogeny. Similarly, the role
of genes in both phylogeny and ontogeny, once seen as rather deterministic, is now conceptualized as highly dependent on
environmental factors, including behavior. Linguistic theories have, in principle, made an effort to incorporate these changing
views. However, the central claim of the given paper is that this apparent compliance with biological insights remains
superficial. As such, considerable disconnects between linguistic theory and what is known about the biological underpinnings of
complex traits persist, negatively impacting pertinent views on language acquisition, language universals and the evolution of
language. Given the breadth of these fields of study, the aim of this paper is to tackle the root of the problem: It begins by
sketching out linguistic nativism as conceptualized within generativism, pointing to aspects within this position that stand in
conflict with the interdisciplinary literature. It will then review select areas of research in a succinct manner in order to
substantiate the criticism and characterize the counterposition as found within the biological sciences. The paper will culminate
in addressing these disconnects on conceptual grounds, i.e. invoking the term emergence as employed in
neuroscience as a possible means to reconcile those biological insights with linguistic nativism.
Challenging Gender Roles and Expectations in Outdoor Field Experiences
Authors: Sassaman Steven
Published: March 2024

Though field experiences require equitable contributions from each member in order to be successful, western socialized gender norms often find themselves playing out as participants who identify as women tend to take the “caretaker” role in tasks such as campsite setup and cooking while those who identify as men often focus on the technical aspects of the activity itself. This case study explores how this frequent dynamic can be challenged and leveraged as an opportunity to more broadly identify how socialized gender norms negatively impact society as a whole.

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© CAB International 2024
Inclusion, Access, and Intersectionality in the Outdoors: A Rock Climbing Case Study of the Salt Lake Area Queer Climbers (SLAQC) Organization
Authors: Hernandez Leandra H. , Kastellec Matthew , Zheng Rue
Published: March 2024

In this case study, we explore our experiences as three of the co-organizers of the Salt Lake Area Queer Climbers (SLAQC) organization, a rock climbing queer advocacy organization based in Salt Lake City. Matty is a queer, cisgender white man, Lea is a queer/pansexual Latina, and Rue is a queer Chinese-American. All of us have been climbing for several years, and Lea and Matty were both active in the Salt Lake Climbers Alliance organization, as well. Utah is a predominantly white, conservative, and religious state, and in spite of obstacles, we have created a homeplace for queer climbers. Our organization breaks down access barriers, gear barriers, and more through partnerships with local gyms, local climbing affinity groups such as Color the Wasatch, gear organizations, and queer climbing guides. In this case study, we explore best practices that we utilize to frame our events and our community outreach, rooted within principles of intersectionality, and reflect upon the 1-year anniversary of SLAQC.

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© CAB International 2024
Not Just Rapids: Navigating Gendered Performance in the Whitewater Rafting Industry
Authors: Schenkemeyer Mandy , Blevins Maria
Published: March 2024

Ideal archetypes of outdoor guides often conjure images of strong men with beards and flannel. While guiding industries are, in fact, man-dominated, many women have been successful in gaining and maintaining employment in outdoor professions. Feminist scholars have outlined concepts of gender performances. Within guiding industries, many women have been adapted by performing masculinity. This case study stems from a larger project examining gender dynamics and issues of harassment within the whitewater raft guiding community. We outline the specific ways in which a dominant masculinity is described by interviewees and the subsequent practices they adopt. Specifically, we discuss how women have enacted masculinity through toughness, assertive communication, and sexual humor. We highlight how these expectations are exclusionary and can be opposed. Through these examples and related literature, we re-envision work cultures that no longer require the additional labor of navigating masculinist environments in order to be accepted and successful.

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© CAB International 2024
The magnetic field does not perform work—or does it?
Authors: Schmidt Heinz-Jürgen , Bröcker Thomas
Published: March 2024

We investigate the question discussed in the literature as to whether the magnetic field can perform work using two models that describe interacting magnetic dipoles. In the first model, the dipoles are realized by rigidly rotating charge clouds, whereas in the second model, one of the two dipoles is described by a real macroscopic spin density. The theoretical foundations of the second model are formulated in a recently published paper. We derive equations of motion and detailed energy balance for both models when the initial magnetic moments are parallel to the connecting line of the initial dipole positions. In this scenario the ‘large’ dipole remains stationary and generates an external magnetic field in which the ‘small’ dipole is accelerated. The answer to the title question depends on the choice of criteria for ‘work of the magnetic field’.
Tunable optical bistability of two-dimensional tilted Dirac system
Authors: Pandey Vivek , Bhalla Pankaj
Published: March 2024

We study the phenomenon of controlling the light by light known as the optical bistability for the two-dimensional tilted Dirac system. Using the Boltzmann approach under relaxation time approximation, we find that the optical bistability can be controlled by the nonlinear response of the system. For the prototype, we consider an inversion symmetry broken system. We find that the optical bistability associated with the nonlinear response is tunable with the strength of the tilt, gap and chemical potential. The resulting features suggest the inputs for the development of future-generation optical devices.
Temporal Variation of Phosphate Contamination In Tropical Epikarst Springs, Gunungsewu Karst Area, Indonesia
Authors: Satrio F A , Singgih A , Cahyadi A , Adji T N
Published: March 2024

Epikarst springs in less developed karst areas typically have predominant diffuse flows where groundwater chiefly moves through spaces between rock grains. This might lead to different flow characteristics between flow dominated by diffuse and dominated by large conduits resulting from dissolution processes. This research aimed to analyze the multitemporal characteristics of phosphate contamination of epikarst spring water in the Gunungsewu Karst Area, Java Island, Indonesia. Phosphate levels were determined from the spring water samples collected every two weeks for nine months to encompass two seasons characteristic of tropical environments: dry and rainy. Results show that the phosphate concentration of the Gedaren Spring exceeded the water quality standard at different times, was likely high in the rainy season and low in dry season and showed positive correlation with rainfall and flow discharge. Further, it was identified that the phosphate was probably generated by agricultural activities or different sources from sulfate and nitrate, as indicated by their weak positive correlations between phosphate-sulfate or phosphate-nitrate.
Prospective Peri-Urban Areas Around the New Capital City of Nusantara, Indonesia: Sustainable Development and New Urban Agenda Perspectives
Authors: Budiman P W , Musthofa A , Reinhart H
Published: March 2024

In 2022, the Indonesian Parliament passed the historical new capital city bill, commencing the relocation of the country’s capital from Jakarta to Nusantara in Kalimantan Timur. This relocation has been predicted to impact the surrounding areas by, for instance, triggering (peri-)urbanization. This research aimed to analyze the locations and roles of peri-urban areas and discuss the processes that drive their emergence and development in the context of the New Urban Agenda. For this purpose, potential peri-urban areas were determined by examining three spatial elements: the development level, accessibility, and position of a village (administrative unit) relative to the capital. Supporting primary data were acquired through a field survey, and secondary data were obtained from the Village Potential Statistics (PODES) from BPS-Statistics Indonesia. Results show that the identified potential peri-urban areas had the following characteristics: (1) situated within the new capital’s development zone, (2) directly adjacent to the capital, (3) having a high level of development and adequate access to the capital, and (4) currently parts of the peri-urban areas of Samarinda and Balikpapan Cities. According to the New Urban Agenda, peri-urban areas can help provide open green space to support rural-urban linkage and perform the new capital’s ecological functions.
Reducing the Susceptibility of Flood Supplier Areas in Gondang Micro-Catchment, Bojonegoro, East Java Province: a Flood Disaster Mitigation Effort
Authors: Hanindityasari L , Auliyani D , Wahyuningrum N , Supangat A B
Published: March 2024

Flood disaster mitigation begins with reducing the susceptibility of flood supplier areas. This task can be accomplished by mapping the flood-supplier susceptibility and then deciding on long-term flood mitigation actions following the susceptibility level of the land and the legal status of its area. Pacal reservoir has Gondang as one of its catchment areas. During the rainy season, the spillway releases water immediately because the inflow exceeds capacity. To maximize water storage, reduce Pacal reservoir input, and prevent downstream flooding, the land cover must be improved. This paper will investigate the Gondang micro-flood-prone catchment’s locations and propose mitigation strategies. The legal status of the land is used, as well as Climate Hazards Group Infrared Precipitation with Station data (CHIRPS), Digital Elevation Model (DEM), and Google Imagery from 2014 and 2020. Paimin’s Equation was used to assess the flood risk. The findings indicate that the Gondang micro-catchment is susceptible to flood suppliers on a low to a high level. Changes in land cover during 2014-2020 resulted in alterations to the susceptibility level of the area. The legal status of the area has had an impact on land cover management. The simulation results of reforestation and maintenance of dense forests in forest areas, as well as regreening activities in agricultural areas, can improve land with high susceptibility to moderate levels, which accounts for 20.9% of micro-catchment areas. All of these proposed activities are expected to control the Pacal Reservoir’s inflow during the rainy season by increasing soil infiltration and reducing runoff.