bluuebunny/crossref_metadata_2025 huggingface dataset:
A tight-binding model for illustrating exciton confinement in semiconductor nanocrystals
Authors: Hens Z. , Delerue C. D.
Published: March 2024

The Brus equation describes the relation between the lowest energy of an electron–hole pair and the size of a semiconductor crystallite. However, taking the strong confinement regime as a starting point, the equation does not cover the transition from weak to strong confinement, the accompanying phenomenon of charge-carrier delocalization, or the change in the transition dipole moment of the electron–hole pair state. Here, we use a one-dimensional, two-particle Hubbard model for interacting electron–hole pairs that extends the well-known tight-binding approach through a point-like electron–hole interaction. On infinite chains, the resulting exciton states exhibit the known relation between the Bohr radius, the exciton binding energy, and the effective mass of the charge carriers. Moreover, by introducing infinite-well boundary conditions, the model enables the transition of the exciton states from weak to strong confinement to be tracked, while straightforward adaptations provide insights into the relation between defects, exciton localization, and confinement. In addition, by introducing the dipole operator, the variation of the transition dipole moment can be mapped when shifting from electron–hole pairs in strong confinement to delocalized and localized excitons in weak confinement. The proposed model system can be readily implemented and extended to different multi-carrier states, thus providing researchers a tool for exploring, understanding, and teaching confinement effects in semiconductor nanocrystals under different conditions.
Application of the dynamic transformer model with well logging data for formation porosity prediction
Authors: Sun Youzhuang , Pang Shanchen , Zhang Yongan , Zhang Junhua
Published: March 2024

Porosity, as a key parameter to describe the properties of rock reservoirs, is essential for evaluating the permeability and fluid migration performance of underground rocks. In order to overcome the limitations of traditional logging porosity interpretation methods in the face of geological complexity and nonlinear relationships, the Dynamic Transformer model in machine learning was introduced in this study, aiming to improve the accuracy and generalization ability of logging porosity prediction. Dynamic Transformer is a deep learning model based on the self-attention mechanism. Compared with traditional sequence models, Dynamic Transformer has a better ability to process time series data and is able to focus on different parts of the input sequence in different locations, so as to better capture global information and long-term dependencies. This is a significant advantage for logging tasks with complex geological structures and time series data. In addition, the model introduces Dynamic Convolution Kernels to increase the model coupling, so that the model can better understand the dependencies between different positions in the input sequence. The introduction of this module aims to enhance the model's ability to model long-distance dependence in sequences, thereby improving its performance. We trained the model on the well log dataset to ensure that it has good generalization ability. In addition, we comprehensively compare the performance of the Dynamic Transformer model with other traditional machine learning models to verify its superiority in logging porosity prediction. Through the analysis of experimental results, the Dynamic Transformer model shows good superiority in the task of logging porosity prediction. The introduction of this model will bring a new perspective to the development of logging technology and provide a more efficient and accurate tool for the field of geoscience.
A new division algebra representation of E7 from E8
Authors: Dray Tevian , Manogue Corinne A. , Wilson Robert A.
Published: March 2024

We decompose the Lie algebra e8(−24) into representations of e7(−25)⊕sl(2,R) using our recent description of e8 in terms of (generalized) 3 × 3 matrices over pairs of division algebras. Freudenthal’s description of both e7 and its minimal representation are therefore realized explicitly within e8, with the action given by the (generalized) matrix commutator in e8, and with a natural parameterization using division algebras. Along the way, we show how to implement standard operations on the Albert algebra such as trace of the Jordan product, the Freudenthal product, and the determinant, all using commutators in e8.
In situ edge extraction enabled by reconfigurable van der Waals infrared photodetectors
Authors: Wang Jinjin , Fang Yueyue , Jiang Yu , Long Siyu , Ma Xinyu , Fu Xiao , She Yihong , Zhao Qixiao , Chen Yue , Xu Hangyu , Li Tangxin , Zhong Fang , Lin Hongyi , Chen Xiaolong , Miao Jinshui
Published: March 2024

At present, the widely used artificial intelligence image perception technology is composed of discrete detection and processing components, which is mismatching the demand for increasingly sizeable redundant image information processing. The transmission of non-critical information between components limits the efficiency of image perception systems. Inspired by the human vision system, which can extract the key features and reduce the transmission burden at the low-level detection end, we propose a symmetric structured mixed-dimensional n/p/n [n-molybdenum disulfide (MoS2)/p-germanium (Ge)/n-MoS2] interdigital van der Waals heterojunction infrared photodetector that can be tuned by bias voltage in response polarity and magnitude. The MoS2/Ge/MoS2 infrared photodetector has a bias-symmetric optoelectronic response and covers the detection band from visible to short-wave infrared. Through the joint detection of a pair of MoS2/Ge/MoS2 infrared photodetectors, we demonstrate the image in situ edge extraction at the detection end, which provides key features for high-level processing. This work has discovered the potential of retina-inspired infrared photodetectors on a 2D/3D integration platform, providing distinct opportunities for a neuromorphic visual perception hardware.
Impact of large A-site cations on electron–vibrational interactions in 2D halide perovskites: Ab initio quantum dynamics
Authors: Dai Dandan , Agrawal Sraddha , Prezhdo Oleg V. , Long Run
Published: March 2024

Using ab initio nonadiabatic molecular dynamics, we study the effect of large A-site cations on nonradiative electron–hole recombination in two-dimensional Ruddlesden–Popper perovskites HA2APb2I7, HA = n-hexylammonium, A = methylammonium (MA), or guanidinium (GA). The steric hindrance created by large GA cations distorts and stiffens the inorganic Pb–I lattice, reduces thermal structural fluctuations, and maintains the delocalization of electrons and holes at ambient and elevated temperatures. The delocalized charges interact more strongly in the GA system than in the MA system, and the charge recombination is accelerated. In contrast, replacement of only some MA cations with GA enhances disorder and increases charge lifetime, as seen in three-dimensional perovskites. This study highlights the key influence of structural fluctuations and disorder on the properties of charge carriers in metal halide perovskites, providing guidance for tuning materials’ optoelectronic performance.
The leaf micromorphology and anatomy of gamba grass, Andropogon gayanus Kunth (Poaceae: Panicoideae)
Authors: Farr Jeremy , Krisantini S. , Fabillo Melodina
Published: March 2024

Context Andropogon gayanus, commonly known as gamba grass, is one of the declared weeds of national significance in Australia. Past studies have focused on gross morphology of root structures, biogeochemical behaviour, and ecology, but there has been limited work on comparative descriptions of leaf micromorphology and anatomy. Aims We investigated and described its leaf micromorphology and anatomy to understand weed biology and ecophysiology. Methods Optical and scanning electron microscope examination of the adaxial and abaxial leaf surfaces of A. gayanus was carried out. We identified and generated a list of morphological characters that were used to compare several dried herbarium specimens of A. gayanus. Key results The leaf characters were consistent across all specimens examined, with minor differences in leaf pubescence, indicating this could be a plastic trait. Conclusions Andropogon gayanus leaves are well adapted to wet and dry tropical conditions. Plasticity in leaf surface pubescence possibly enhances its adaptability, increasing its success as a weed in Australian ecosystems. The success of A. gayanus in Australia could be because the environment compares favourably with the native environment of the species in Africa, where it has adapted to extremes of wet and dry conditions over a large geographical range. Implications Plant morphological and taxonomic studies of A. gayanus focused on describing characters of spikelets and caryopses are recommended to understand how reproductive structures aid in its successful proliferation.
Breaking the cosmological principle into pieces: a prelude to the intrinsically homogeneous and isotropic spacetimes
Authors: Gomes L G
Published: March 2024

In this manuscript, we show that there are three fundamental building blocks supporting the cosmological principle. The first of them states that there is a special frame in the Universe where the spatial geometry is intrinsically homogeneous and isotropic. The second demands the existence of a fiducial observer to whom the Hubble parameter is isotropic. The last piece states that matter and radiation behave as a perfect fluid. We show that these three hypotheses give us the Friedmann–Lemaître–Robertson–Walker (FLRW) spacetimes, the central pillar of the standard model of cosmology. We keep with the first of them and start to investigate the so-called intrinsically homogeneous and isotropic spacetimes. They emerge after the decoupling of the CMB with the geometric frame of reference. Furthermore, a ‘ΛCDM-like’ effective theory arises naturally in those backgrounds, together with some new density parameters relating to the local inhomogeneities, the internal energy density, and the local and global magnitudes of the Hubble anisotropy. All those properties make this class of inhomogeneous models, which roughly speaking, keeps ‘1/3’ of the cosmological principle, worth investigating in applications to cosmology, for it can accommodate the same ingredients of the standard model, as a geometric frame and a free-falling isotropic cosmic background radiation, and reduce to the latter when some observable parameters vanish.
Matrix recovery from nonconvex regularized least absolute deviations
Authors: Xu Jiao , Li Peng , Zheng Bing
Published: March 2024

In this paper, we consider the low-rank matrix recovery problem. We propose the nonconvex regularized least absolute deviations model via

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minimization. We establish the theoretical analysis of the proposed model and obtain a stable error estimation. Our result is a nontrivial extension of some previous work. Different from most of the state-of-the-art methods, our method does not need any knowledge of standard deviation or any moment assumption of the noise. Numerical experiments show that our method is effective for many types of noise distributions.
Coherent energy transfers between orthogonal modes of a dielectric cavity bridged by a plasmonic antenna
Authors: Xie Bo , Ma Lin , You Yue , Du Xiao-Jing , Hu Ma-Long , Tang Xu-Tao , He Jun , Yang Zhong-Jian
Published: March 2024

Here, we demonstrate a strategy that two orthogonal modes in a dielectric cavity can efficiently couple with each other through the bridging effect of a plasmonic antenna. In such a dielectric-antenna hybrid system, a plasmonic antenna can coherently interact with both modes of the dielectric cavity, which brings sufficient coherent energy transfers between the two orthogonal modes. Specifically, a broad electromagnetic mode and a narrow whispering gallery mode (WGM) in a subwavelength silicon disk are considered, where they cannot directly interact with each other through near-field couplings. By introducing a plasmonic antenna, coherent energy transfer between the above two modes occurs, which is confirmed by both far-field spectra and near-field distributions. More investigations show that spectral and spatial overlaps between the involved modes can largely affect energy transfer behaviors. Those overlaps are highly dependent on various parameters of the system. The WGM response in the hybrid system can even exceed that of an individual disk. Our proposed strategy can be extended to other similar systems and the modified optical responses can find applications in enhanced light-matter interactions.
Basic characteristics of Vision badge and its performance as an eye lens dosimeter for endoscopists
Authors: Fukushima Kotaro , Matsubara Kosuke , Ichikawa Nao
Published: March 2024

Vision badge is an eye lens dosimeter to measure H
p(3). This study aimed to evaluate the basic characteristics of the Vision badge and its performance as an eye lens dosimeter for endoscopists by phantom study. Energy dependence was evaluated by changing the tube voltage to 50 kV (effective energy of 27.9 keV), 80 kV (32.2 keV), and 120 kV (38.7 keV). Dose linearity was evaluated by changing the number of irradiation to 1, 5, and 40 times, which corresponded to 0.53, 5.32, and 21.4 mGy. Batch uniformity was evaluated by calculating the coefficient of variation of H
p(3) obtained from 10 Vision badges. Angular dependence was evaluated at 0° (perpendicular to the incident direction of x-rays), 30°, 60°, 75°, and 90°. The Vision badge and optically stimulated luminescence (OSL) dosimeter were attached to the inside of the radioprotective glasses, worn on the endoscopist phantom, and the H
p(3) obtained from both dosimeters were compared. The H
p(3) obtained from the Vision badge with 38.7 keV was 3.8% higher than that with 27.9 keV. The Vision badge showed excellent linearity (R
2 = 1.00) with the air kerma up to 21.4 mGy. The coefficient of variation of the H
p(3) for 10 Vision badges was 3.47%. The relative dose of the Vision badge decreased as the angle increased up to 75°, but increased at 90°. The H
p(3) obtained by the OSL dosimeter and the Vision badge were decreased as the endoscopist phantom was turned away from the patient phantom. The H
p(3) that was obtained by the Vision badge was 35.5%–55.0% less than that obtained by the nanoDot. In conclusion, the Vision badge showed specific angular dependence due to its shape, but satisfactory basic properties were exhibited for all characteristics. In phantom study, the Vision badge showed generally similar trends with the OSL dosimeter.
Blood flow restriction attenuates surface mechanomyography lateral and longitudinal, but not transverse oscillations during fatiguing exercise
Authors: Hill Ethan C , Proppe Chris E , Rivera Paola M , Lubiak Sean M , Gonzalez Rojas David H , Lawson John E , Choi Hwan , Mansy Hansen , Keller Joshua L
Published: March 2024

Objective. Surface mechanomyography (sMMG) can measure oscillations of the activated muscle fibers in three axes (i.e. X, Y, and Z-axes) and has been used to describe motor unit activation patterns (X-axis). The application of blood flow restriction (BFR) is common in exercise studies, but the cuff may restrict muscle fiber oscillations. Therefore, the purpose of this investigation was to examine the acute effects of submaximal, fatiguing exercise with and without BFR on sMMG amplitude in the X, Y, and Z-axes among female participants. Approach. Sixteen females (21 ± 1 years) performed two separate exercise bouts to volitional exhaustion that consisted of unilateral, submaximal (50% maximal voluntary isometric contraction [MVIC]) intermittent, isometric, leg extensions with and without BFR. sMMG was recorded and examined across percent time to exhaustion (%TTE) in 20% increments. Separate 2-way repeated measures ANOVA models were constructed: (condition [BFR, non-BFR]) × (time [20, 40, 60, 80, and 100% TTE]) to examine absolute (m·s−2) and normalized (% of pretest MVIC) sMMG amplitude in the X-(sMMG-X), Y-(sMMG-Y), and Z-(sMMG-Z) axes. Main results. The absolute sMMG-X amplitude responses were attenuated with the application of BFR (mean ± SD = 0.236 ± 0.138 m·s−2) relative to non-BFR (0.366 ± 0.199 m·s−2, collapsed across time) and for sMMG-Y amplitude at 60%–100% of TTE (BFR range = 0.213–0.232 m·s−2 versus non-BFR = 0.313–0.445 m·s−2). Normalizing sMMG to pretest MVIC removed most, but not all the attenuation which was still evident for sMMG-Y amplitude at 100% of TTE between BFR (72.9 ± 47.2%) and non-BFR (98.9 ± 53.1%). Interestingly, sMMG-Z amplitude was not affected by the application of BFR and progressively decreased across %TTE (0.332 ± 0.167 m·s−2 to 0.219 ± 0.104 m·s−2, collapsed across condition.) Significance. The application of BFR attenuated sMMG-X and sMMG-Y amplitude, although normalizing sMMG removed most of this attenuation. Unlike the X and Y-axes, sMMG-Z amplitude was not affected by BFR and progressively decreased across each exercise bout potentially tracking the development of muscle fatigue.
Hollow vortex Gaussian beam expressed in terms of cylindrical wave
Authors: Zhong Shiliang , Lin Jianxin , Shen Jianqi
Published: March 2024

The electrical field of hollow vortex Gaussian beam (HVGB) with an arbitrary combination of the beam order and topological charge is formulated by using the cylindrical wave spectrum representation (CWSR), which satisfies Maxwell’s equations rigorously and allows to study analytically and numerically the evolution of the beam along its propagation in the source region and the near/far- field regions. It is found that in the source region there exists a sharp and very narrow peak, due to the contribution of evanescent waves when the beam order and the topological charge satisfy specific relations. The effect of the spiral phase plate (SPP) in generating a non-vortex Gaussian beam to a vortex one is explained. Besides, it is found that the divergence of the beam is mainly determined by the topological charge and the hollow structure is mainly determined by the beam order.
Identifying key products to trigger new exports: an explainable machine learning approach
Authors: Fessina Massimiliano , Albora Giambattista , Tacchella Andrea , Zaccaria Andrea
Published: March 2024

Tree-based machine learning algorithms provide the most precise assessment of the feasibility for a country to export a target product given its export basket. However, the high number of parameters involved prevents a straightforward interpretation of the results and, in turn, the explainability of policy indications. In this paper, we propose a procedure to statistically validate the importance of the products used in the feasibility assessment. In this way, we are able to identify which products, called explainers, significantly increase the probability to export a target product in the near future. The explainers naturally identify a low dimensional representation, the Feature Importance Product Space, that enhances the interpretability of the recommendations and provides out-of-sample forecasts of the export baskets of countries. Interestingly, we detect a positive correlation between the complexity of a product and the complexity of its explainers.
Unravelling the genetic diversity and taxonomic ambiguities of endemic Petunia species from subtropical highland grasslands
Authors: Souza Analu C , Soares Luana S , Backes Alice , Simon Luize , Pezzi Pedro H , Turchetto Caroline , Freitas Loreta B
Published: March 2024

Closely related and young species often show high morphological similarity, challenging their identification and correct assignment. Molecular markers and integrative approaches have contributed to solving many taxonomic uncertainties. In this study, we evaluated the genetic variability and ecological features of Petunia guarapuavensis and Petunia scheideana, over which there is a taxonomic debate. Both species are endemic and rare, distributed in the subtropical highland grasslands in southern South America. We based our analyses on nuclear microsatellite and plastid sequences, aiming to disentangle the taxonomic ambiguities that made some consider these entities synonymous despite occupying different clades in the genus phylogenetic tree. Our findings support that there is genetic differentiation between these species, suggesting that they are independent taxonomic entities despite sharing floral traits and a few molecular polymorphisms. The low genetic sharing between the species is likely due to a common ancestor and recent divergence time. In contrast, their morphological similarity can be attributed to the absence of selective pressure, as both grow under similar ecological conditions. This study emphasizes that adding more than one sequence per species, combining data with dissimilar inheritance patterns, and exploring data through different methodologies help to disentangle taxonomic incongruences and reveal diversity that might otherwise remain hidden.
Learning, thinking, sharing, and working across boundaries in fisheries science
Authors: Cooke Steven J , Arlinghaus Robert
Published: March 2024

Fisheries science and practice are challenging and require learning, thinking, and sharing across boundaries. The idea of boundary crossing can be described as some form of multiple disciplinarity (e.g. interdisciplinarity, transdisciplinarity), yet that inherently implies that the boundaries crossed are purely disciplinary in nature. After working across various other boundaries (i.e. realms, regions, disciplines, sectors, domains, and knowledge systems) for most of our educational journeys and professional careers, we reflect on our lived experiences with a focus on identifying the benefits and challenges of engaging in different types of boundary crossing. We submit that our personal and professional lives have been enriched by stepping outside of our immediate comfort zones and expertise (i.e. fish ecology) and engaging in active listening and learning with colleagues in other disciplines (i.e. various social sciences) and with stakeholders and policymakers. We have learned much from working across boundaries and encourage others, especially early career professionals, to do the same. What may superficially appear to be a bridge too far may in fact provide novel ways of thinking about a given issue or topic that generates actionable science for sustainable fisheries management and conservation. Many of the projects that we consider to be our greatest successes represent ones that involved boundary crossing, examples of which we provide in this essay. There is a need to prepare the next generation of problem solvers for engaging in boundary crossing and celebrating examples of where such efforts have led to meaningful advances in fisheries science and practice. Ensuring that institutional and cultural barriers that may constrain boundary crossing are addressed while also supporting those doing such work will be key to address the many fisheries and aquatic science challenges of today and tomorrow in both marine and freshwater systems.
Alcohol consumption and the risk of all-cause and cause-specific mortality—a linear and nonlinear Mendelian randomization study
Authors: Kassaw Nigussie Assefa , Zhou Ang , Mulugeta Anwar , Lee Sang Hong , Burgess Stephen , Hyppönen Elina
Published: March 2024

Background

Many observational studies support light-to-moderate alcohol intake as potentially protective against premature death. We used a genetic approach to evaluate the linear and nonlinear relationships between alcohol consumption and mortality from different underlying causes.

Methods

We used data from 278 093 white-British UK Biobank participants, aged 37–73 years at recruitment and with data on alcohol intake, genetic variants, and mortality. Habitual alcohol consumption was instrumented by 94 variants. Linear Mendelian randomization (MR) analyses were conducted using five complementary approaches, and nonlinear MR analyses by the doubly-ranked method.

Results

There were 20 834 deaths during the follow-up (median 12.6 years). In conventional analysis, the association between alcohol consumption and mortality outcomes was ‘J-shaped’. In contrast, MR analyses supported a positive linear association with premature mortality, with no evidence for curvature (Pnonlinearity ≥ 0.21 for all outcomes). The odds ratio [OR] for each standard unit increase in alcohol intake was 1.27 (95% confidence interval [CI] 1.16–1.39) for all-cause mortality, 1.30 (95% CI 1.10–1.53) for cardiovascular disease, 1.20 (95% CI 1.08–1.33) for cancer, and 2.06 (95% CI 1.36–3.12) for digestive disease mortality. These results were consistent across pleiotropy-robust methods. There was no clear evidence for an association between alcohol consumption and mortality from respiratory diseases or COVID-19 (1.32, 95% CI 0.96–1.83 and 1.46, 95% CI 0.99–2.16, respectively; Pnonlinearity ≥ 0.21).

Conclusion

Higher levels of genetically predicted alcohol consumption had a strong linear association with an increased risk of premature mortality with no evidence for any protective benefit at modest intake levels.
Novel resveratrol smart lipids; design, formulation, and biological evaluation of anticancer activity
Authors: Diab Reem Fekry , Abdelghany Tamer M , Gad Shadeed , Elbakry Asmaa M
Published: March 2024

Purpose

Although resveratrol (RES) is an efficacious molecule, its therapeutic activity is impeded by significant limitations, such as rapid oral absorption, poor oral bioavailability, and low water solubility. Therefore, the preparation of RES in different pharmaceutical carriers represents an important tool to enhance its therapeutic applications. This study aims to potentiate the anti-cancer activity of RES by formulating it into a novel nanocarrier called Smart Lipid.

Methods

RES-loaded Smart Lipids were prepared by high-shear hot homogenization method utilizing a 21 × 32 factorial design with three factors at different levels: the total lipid concentration, the concentration of surfactant, and the type of surfactant. The responses were evaluated based on entrapment efficiency percentages and particle size.

Results

Our novel optimized RES-loaded Smart Lipid formula showed small particle size (288.63 ± 5.55 nm), good zeta potential (−16.44 ± 0.99 mV), and an entrapment efficiency of 86.346 ± 3.61% with spherical, clearly distinct, and no signs of fusion by transmission electron microscopy. Further characterization was done using differential scanning calorimetry, which showed no interaction between the drug and other components as the optimum lyophilized formula showed a peak at 54.75°C, which represents the lipid mixture, with an undetectable characteristic peak of the drug, which indicates entrapment of the drug, and the structure of the compounds was confirmed by Fourier transform-infrared spectroscopy, in which the majority of the drug’s characteristic peaks disappeared when loaded into Smart Lipid, which may indicate Smart Lipid’s ability to reduce the stretching and bending between bonds in RES. In addition, the optimized formula showed a sustained release pattern compared to RES suspension. Finally, the cytotoxic activity of the optimized RES-loaded Smart Lipid on different cell lines (human breast adenocarcinoma (MCF7), human hepatocellular carcinoma (HepG2), and human colon cancer cells (HT29)) was assessed through MTT assay (7-fold reduction in the IC50, from 3.7 ± 0.5 μM for free RES to 0.5 ± 0.033 μM for Smart Lipid loaded formula against MCF7, 3-fold reduction in the IC50 against HepG2 cells, from 10.01 ± 0.35 to 3.16 ± 0.21 μMm, and a more than 10-fold reduction in the IC50 from more than 100 to 10 ± 0.57 μM against HT-29 cells) and its effect on cell cycle progression and apoptosis induction were assessed using flow cytometry and annexin V kit, respectively. Our results showed that RES-loaded Smart Lipid significantly reduced cell viability, induced cell cycle arrest at G0/G1 phase, and apoptosis compared to free formula and free RES suspension.

Conclusion

Loading RES into this novel kind of nanocarrier enhanced RES absorption, cellular accumulation, and improved its anticancer properties.
Vietnam War
Authors: Black Samuel W.
Published: March 2024

African Americans have served in every war of the United States and colonial America dating back to the French and Indian War (1756–1763). By the time the United States involved itself in the Vietnam conflict (1955–1973), over 250,000 African Americans had served in country, stateside, or in a US military outpost in Europe, Southeast Asia or the Far East. The Vietnam War was fought during the Cold War amid the civil rights, Black Power, women’s rights, and voting rights movements. As early as 1945 the US government had an opportunity to work with the Viet Minh under Ho Chi Minh to actualize the independence of Vietnam. Instead, it supported the French repatriation of its Southeast Asia colony, Indochina. Thus, the start of the First Indochina War in 1946 witnessed French forces that included Francophone African soldiers. The United States supported the French with intelligence, weapons, and financing. After the French defeat at Dien Bien Phu in 1954, the United States remained invested in South Vietnam using a policy of stopping the spread of communism in Asia. Initially serving as advisors and offering training and support to the army of the Republic of Vietnam, the United States slowly escalated its advisory force and then by the early 1960s added combat units. African American soldiers were part of the military initiative all along. Although President Harry S. Truman had integrated the armed forces with Executive Order 9981 in 1948 and its trial in the Korean War in the early 1950s, the Vietnam War became the first American war to have a fully sanctioned racially integrated military. The era of the Vietnam War, from the mid-1950s to the early 1970s, was also the era of major civil rights activities. Civil rights and Vietnam crossed paths on many occasions and was exploited by various factions indicating that the military was not immune to the social and political challenges of civil rights. The civil rights movement also meant a heightened scrutiny of the war. Some African Americans protested the war as an extension of the civil rights movement. Iconic protesters like Muhammad Ali came to symbolize defiance to America’s foreign policies. However, those who did serve did so with valor. Twenty African Americans were recipients of the Congressional Medal of Honor. The focus of this article is to provide a guide to sources and documentation of useful works that address the complex history of the Vietnam War and the role of African Americans in it.
Motherscholars
Authors: CohenMiller Anna , Leveto Jessica
Published: March 2024

The origin of the concept “motherscholars” is a purposeful connection linking identifying as a mother and identifying as a scholar. In many parts of the world, for those working in educational institutions, being a mother is often hidden and not discussed. In particular, being recognized as a mother in the workplace in the United States and the United Kingdom has often designated women as less capable in their day-to-day work. Thus, keeping motherhood hidden has offered many mothers a chance to maintain status that diminishes once becoming associated with mothering. While there are many studies that examine the experiences of being both a mother and a scholar, this article focuses on the purposeful integration of the two aspects as a form of advocacy to showcase the presence of the multiple identities of the individual. This means that the references included here will not include texts that discuss for instance the broad topic of participants who were mothers and working in educational institutions in general. Instead, the entry emphasizes the texts that link these ideas together in a commitment to spark awareness and acceptance, primarily focused on higher education/academia.
Critical Historical Geography
Authors: Clayton Dan
Published: March 2024

This is an interesting entry to compile in that while most work in historical geography—the subdiscipline of geography concerned with the past and its relations with the present—might now be called “critical historical geography,” the term is scarcely defined. Its story involves changing geographies of environmental and social change (encompassing problems of capitalism, modernity, empire, nation, globalization, violence, and planetary peril, to name just the most prominent) and thus serves as a commentary on changing times and current predicaments from a specific (if eclectic) area of inquiry. This story has been integral to the journey of “critical geography” over the last sixty years: to fostering recognition that the questions and things the geographer studies are bound up with the past and have a history. Geographical interest in the past is not the preserve of historical geography (the boundaries of the subdiscipline are porous), and not all work referenced in this bibliography comes from researchers who identify themselves as historical geographers. Our term shall be annotated in three (overlapping) ways: to denote, first, work in historical geography that is informed by theory and philosophy (especially questions of power, knowledge, representation, materiality, identity, memory, difference, and human-animal-nature linkages) and has a normative concern not simply with understanding the world but also with trying to change it for the better; second, wider theoretical debates that have grappled with how questions of geography and space are critical (vital) to understanding time and history, and vice versa; and third, historical geographers’ instinctive sensitivity to methodological questions and how the times and spaces in which they live and work influence what they do—and with “the archive” a key material and social entity and relation (object, site, practice, and way of seeing and knowing). A general overview of this tripartite definition is followed by more detailed commentaries on the three facets, which are given the section headings “Critical of . . .”; “Critical to . . .”; and “Critical Reflexivity . . .” With over one hundred references, the first section is the mainstay of the entry. It recounts the growing and changing scope of critical historical geography by decade and theme (albeit with some intersecting threads), and chronicles from where new and different interests and bodies of work emanate. In all, the following attempt to “curate” this entry is just that: a selective and subjective story, a construct.
Phagocyte-expressed glycosaminoglycans promote capture of alphaviruses from the blood circulation in a host species-specific manner
Authors: Ander Stephanie E , Parks M Guston , Davenport Bennett J , Li Frances S , Bosco-Lauth Angela , Carpentier Kathryn S , Sun Chengqun , Lucas Cormac J , Klimstra William B , Ebel Gregory D , Morrison Thomas E
Published: March 2024

The magnitude and duration of vertebrate viremia are critical determinants of arbovirus transmission, geographic spread, and disease severity—yet, mechanisms determining arbovirus viremia levels are poorly defined. Previous studies have drawn associations between in vitro virion-glycosaminoglycan (GAG) interactions and in vivo clearance kinetics of virions from blood circulation. From these observations, it is commonly hypothesized that GAG-binding virions are rapidly removed from circulation due to ubiquitous expression of GAGs by vascular endothelial cells, thereby limiting viremia. Using an in vivo model for viremia, we compared the vascular clearance of low and enhanced GAG-binding viral variants of chikungunya, eastern- (EEEV), and Venezuelan- (VEEV) equine encephalitis viruses. We find GAG-binding virions are more quickly removed from circulation than their non-GAG-binding variant; however individual clearance kinetics vary between GAG-binding viruses, from swift (VEEV) to slow removal from circulation (EEEV). Remarkably, we find phagocytes are required for efficient vascular clearance of some enhanced GAG-binding virions. Moreover, transient depletion of vascular heparan sulfate impedes vascular clearance of only some GAG-binding viral variants and in a phagocyte-dependent manner, implying phagocytes can mediate vascular GAG-virion interactions. Finally, in direct contrast to mice, we find enhanced GAG-binding EEEV is resistant to vascular clearance in avian hosts, suggesting the existence of species-specificity in virion-GAG interactions. In summary, these data support a role for GAG-mediated clearance of some viral particles from the blood circulation, illuminate the potential of blood-contacting phagocytes as a site for GAG-virion binding, and suggest a role for species-specific GAG structures in arbovirus ecology.
Tocilizumab discontinuation after remission achievement in patients with adult-onset Still’s disease
Authors: Tamai Hiroya , Kondo Yasushi , Takeuchi Tsutomu , Kaneko Yuko
Published: March 2024

Objectives

Tocilizumab, an IL-6 inhibitor, has been proven effective in patients with adult-onset Still's disease (AOSD). This study aimed to clarify whether tocilizumab can be discontinued after achieving remission and to identify factors relevant to its successful discontinuation.

Methods

Consecutive patients with AOSD diagnosed according to Yamaguchi's criteria from April 2012 to July 2022, who were treated with tocilizumab, were retrospectively reviewed.

Results

Forty-eight patients with AOSD treated with intravenous tocilizumab, with sufficient information, were included. Thirty-eight patients (79.2%) achieved remission after 6 months of tocilizumab treatment, 12 of whom discontinued tocilizumab during remission. Within 1 year after tocilizumab discontinuation, six patients (50.0%) recurred at a mean of 5.5 months, while the other six (50.0%) remained in remission. Between the non-recurrence and recurrence groups, no difference was found in disease activity at tocilizumab discontinuation (systemic feature score, P = 0.24; ferritin, P = 0.46). While the duration of tocilizumab use was not different (P = 0.32), the interval of tocilizumab administration at tocilizumab discontinuation in the recurrence group was 21 (14–35) days, which tended to be shorter than 35 (28–53) days in the non-recurrence group (P = 0.08). Patients with prednisolone dose <7 mg/day at last tocilizumab treatment had fewer recurrences than those without (P = 0.001). After recurrence, tocilizumab was resumed in half of the patients, resulting in successful disease control.

Conclusions

The recurrence rate after tocilizumab discontinuation was 50% in 1 year. Patients who remained in remission with a longer interval of tocilizumab administration and lower prednisolone dose were likely to succeed in the withdrawal of tocilizumab.
Reconstruction of Plantar Forefoot Area with Lateral Toe Pulp Flap: Case Report and Literature Review
Authors: Hung Chen-Ting , Lee Jiunn-Tat , Wu Meng-Si , Cheng Li-Fu
Published: March 2024

Reconstruction of the plantar forefoot area is challenging because it performs important functions, including carrying the body weight and balancing the ambulation gait, and lacks similar skin and soft tissues to manage the adjacent region. Herein, we shared our experience of using a lateral toe pulp flap and reviewed the relevant literature on this topic. A 33-year-old man presented with a large granuloma in the left plantar forefoot area after undergoing multiple operations owing to the diagnosis of callus. After tumor excision, the wound exhibited tendon exposure and a large infected dead space in the myofascial layer. After serial debridement with negative pressure wound therapy, the wound, which measured ~3.5 × 2.5 cm2, was reconstructed using a lateral toe pulp flap. The flap was transposed to obliterate the dead space; the remaining skin defect (size: ~2 × 2 cm2) was resurfaced with a full-thickness skin graft, harvested from the left inguinal region, followed by primary closure of the flap donor site. The flap completely survived. The lateral toe pulp flap is an easy, effective, and reliable option for reconstruction of the defects in the plantar forefoot area.
Jamming problems and the effects of compliance in dual peg-hole disassembly
Authors: Goli Farzaneh , Zhang Yongquan , Qu Mo , Zang Yue , Saadat Mozafar , Pham Duc Truong , Wang Yongjing
Published: March 2024

Disassembly is a crucial step in remanufacturing and is currently mainly performed by humans. Automating disassembly can reduce labour costs and make remanufacturing more economically attractive. This paper focuses on identifying and characterizing a common disassembly task, dual peg-hole disassembly, with the aim of building a robotic disassembly system for this task. We enumerate the possible contact states and their geometric conditions during the extraction of two studs in a dual peg-hole. This paper focuses on jamming in the extraction and conducts geometrical and quasi-static analyses to determine the boundary conditions of jamming. Based on the analyses, this paper also investigates the role of active compliance as a solution to avoid jamming. We also simulate critical variables and examine key parameters such as the degree of compliance, the location of the compliance centre and initial position errors. Finally, we conduct experimental studies on dual peg-hole extraction with different compliance centres obtained using active compliance.
Scattering of surface waves by inhomogeneities in crystalline structures
Authors: Sharma Basant Lal
Published: March 2024

In current scientific and technological scenarios, studies of transmittance of surface waves across structured interfaces have gained some wind amidst applications to metasurfaces, electronic edge-waves, crystal grain boundaries, etc. The results presented in the present article shed a light on the influence of material inhomogeneities on propagation of surface waves. Within the framework of classical mechanics, an analogue of the Gurtin–Murdoch model is employed where elastic properties on surface are assumed to be distinct from bulk. Restricting to scalar waves on prototype square lattice half-plane, particles on considered structured surface have piecewise-constant mass and surface force-constants across an interfacial point. Particles in bulk lattice interact with nearest neighbours in a way that involves unequal force-constants parallel to surface versus normal to it. A surface wave band exists for such lattice structure wherein the waveform decays exponentially inside the half-plane. A formula for surface wave transmittance is given based on an exact solution on half-plane, and, thus, previous work (Sharma & Eremeyev 2019
Int. J. Eng. Sci.
143
, 33–38 (
doi:10.1016/j.ijengsci.2019.06.007
)) is extended. An explicit expression for fraction of energy influx leaked via bulk waves is a highlight. Included are graphical results for several illustrative values of surface structure parameters.
Human brains preserve in diverse environments for at least 12 000 years
Authors: Morton-Hayward Alexandra L. , Anderson Ross P. , Saupe Erin E. , Larson Greger , Cosmidis Julie G.
Published: March 2024

The brain is thought to be among the first human organs to decompose after death. The discovery of brains preserved in the archaeological record is therefore regarded as unusual. Although mechanisms such as dehydration, freezing, saponification, and tanning are known to allow for the preservation of the brain on short time scales in association with other soft tissues (≲4000 years), discoveries of older brains, especially in the absence of other soft tissues, are rare. Here, we collated an archive of more than 4400 human brains preserved in the archaeological record across approximately 12 000 years, more than 1300 of which constitute the only soft tissue preserved amongst otherwise skeletonized remains. We found that brains of this type persist on time scales exceeding those preserved by other means, which suggests an unknown mechanism may be responsible for preservation particular to the central nervous system. The untapped archive of preserved ancient brains represents an opportunity for bioarchaeological studies of human evolution, health and disease.
Congruity of genomic and epidemiological data in modelling of local cholera outbreaks
Authors: Wilinski Mateusz , Castro Lauren , Keithley Jeffrey , Manore Carrie , Campos Josefina , Romero-Severson Ethan , Domman Daryl , Lokhov Andrey Y.
Published: March 2024

Cholera continues to be a global health threat. Understanding how cholera spreads between locations is fundamental to the rational, evidence-based design of intervention and control efforts. Traditionally, cholera transmission models have used cholera case-count data. More recently, whole-genome sequence data have qualitatively described cholera transmission. Integrating these data streams may provide much more accurate models of cholera spread; however, no systematic analyses have been performed so far to compare traditional case-count models to the phylodynamic models from genomic data for cholera transmission. Here, we use high-fidelity case-count and whole-genome sequencing data from the 1991 to 1998 cholera epidemic in Argentina to directly compare the epidemiological model parameters estimated from these two data sources. We find that phylodynamic methods applied to cholera genomics data provide comparable estimates that are in line with established methods. Our methodology represents a critical step in building a framework for integrating case-count and genomic data sources for cholera epidemiology and other bacterial pathogens.
Microbiota of healthy dogs demonstrate a significant decrease in richness and changes in specific bacterial groups in response to supplementation with resistant starch, but not psyllium or methylcellulose, in a randomized cross-over trial.
Authors: Salavati Schmitz Silke , Salgado Jorge Perez-Accino , Glendinning Laura
Published: March 2024

Even though dietary fibers are often used as prebiotic supplements in dogs, the effect of individual types of fibers on canine microbiota composition is unknown. The objective of this study was to assess changes in fecal microbiota richness, diversity and taxonomic abundance with 3 different fiber supplements in dogs. These were psyllium husk, resistant starch from banana flour and methylcellulose. They were administered to 17 healthy dogs in a cross-over trial after transition to the same complete feed. Fecal scores and clinical activity indices were recorded, and fecal samples collected before and at the end of supplementation, as well as 2 weeks after each supplement (washout). Illumina NovaSeq paired-end 16S rRNA gene sequencing was performed on all samples. After quality control and chimera removal, alpha diversity indices were calculated with QIIME. Differences in specific taxa between groups were identified using Metastats. Methylcellulose significantly increased fecal scores but had no effect on microbiota. Psyllium resulted in minor changes of specific taxa abundance, but with questionable biological significance. Resistant starch reduced microbiota richness and resulted in the most abundant changes in taxa, mostly a reduction in short-chain fatty acid producing genera of the Bacillota phylum, with an increase in genera within the Bacteroidota, Pseudomonadota, Actinomycetota and Saccharibacteria. In conclusion, while psyllium and methylcellulose led to few changes in the microbiota composition, the taxonomic changes seen with resistant starch may indicate a less favorable composition. Based on this, the type of resistant starch used here cannot be recommended as a prebiotic in dogs.