bluuebunny/crossref_metadata_2025_split huggingface dataset:
Copper-Mediated C–O/C–N Bond Formation: A Facile Synthesis of 3-Amidocoumarin, 3-Amidoazacoumarin, and N-Aroylindole ­Derivatives
Authors: Thasana Nopporn , Worayuthakarn Rattana , Suddee Nattanit , Nealmongkol Prattya , Ruchirawat Somsak 
Published: March 2022

AbstractThree different heterocyclic systems (3-amidocoumarins, 3-amidoazacoumarins, and N-benzoylindol-2-carboxamides) were synthesized based on the strikingly different selectivity of copper-mediated C–O/C–N bond formation from azlactones under various heating conditions. The stereochemistry of the double bond dictated the nature of the products. Microwave irradiation played an important role in the isomerization of the trisubstituted olefin leading to the formation of 3-amidocoumarins and 3-amidoazacoumarins. Three products showed promising-to-good cytotoxic activities against a panel of cancer cell lines, including HepG2 (hepatoblastoma) and MOLT-3 (T-lymphoblast acute lymphoblastic leukemia).
Acyclic Quaternary Carbon Stereocenters through Transition-Metal-Catalyzed Enantioselective Functionalization of Unsaturated Hydrocarbons
Authors: Li Bi-Jie , Sun Xin 
Published: March 2022

AbstractAcyclic quaternary carbon stereocenters occur frequently in natural products, bioactive molecules, and pharmaceutical compounds. Construction of a carbon stereogenic center attached to four different carbons with defined spatial arrangement is a daunting challenge in asymmetric catalysis. Significant efforts have been directed towards the stereoselective construction of such acyclic quaternary carbon stereocenters. In particular, catalytic generation of acyclic quaternary carbon stereocenters through functionalization of unsaturated hydrocarbons is an extremely attractive approach because unsaturated hydrocarbons are easily accessible both in industry and in organic synthesis. In this short review, we summarize the recent advances achieved in this research area, with the aim to inspire future development.1	Introduction2	Acyclic Quaternary Carbon Stereocenters through Functionalization of Allenes3	Acyclic Quaternary Carbon Stereocenters through Functionalization of Dienes4	Acyclic Quaternary Carbon Stereocenters through Functionalization of Mono-alkenes5	Acyclic Quaternary Carbon Stereocenters through Functionalization of Alkynes6	Summary and Outlook
Recent Developments in N2-Selective Functionalizations of 1,2,3-Triazoles
Authors: Zhu Li-Li , Wang Yahui , Zheng Yue , Tian Lifang , Ramadoss Velayudham , Zhang Hui 
Published: March 2022

AbstractThe widespread use of 1,2,3-triazole compounds in drugs has resulted in a great interest in the efficient synthesis of N2-substituted 1,2,3-triazoles via post triazole functionalization methods. At present, there are many methods for the synthesis of N1-substituted 1,2,3-triazole compounds, but the development of convenient methods for the N2-selective functionalization of 1,2,3-triazoles remains challenging. In general, the greater stability of the N1 tautomer makes the N2 position a non-preferable reactive site, which has limited the application of 1,2,3-triazoles. In this review, we summarized advances in the direct N2-selective functionalization of 1,2,3-triazoles since 2008.1	Introduction2	N2-Alkylation3	N2-Allylation4	N2-Propargylation5	N2-Alkenylation6	N2-Alkynylation7	N2-Arylation8	Conclusions and Outlook
Fluorinated Olefinic Lactams: The Case of Amino Acids – Preparation and Mechanistic Studies
Authors: Koroniak-Szejn Katarzyna , Salamon-Krokosz Katarzyna , Gołdyn Mateusz , Siodła Tomasz , Bartoszak-Adamska Elżbieta , Koroniak Henryk 
Published: March 2022

AbstractHerein, we report the synthesis of analogues of amino acids with a monofluorovinyl moiety. Interestingly, we have found that cyclization of the obtained products proceeds easily in all cases. The cyclization process has not previously been observed at this reaction stage, and such fluorinated lactams derived from phenylalanine, valine, alanine have not been described before.
Vascularized Lymph Node Transfer for the Treatment of Posttraumatic Lower Extremity Lymphedema: A Preliminary Report
Authors: Ciudad Pedro , Huayllani Maria T. , Forte Antonio J. , Boczar Daniel , Avila Francisco R. , Escandón Joseph M. , Manrique Oscar J. , Chen Hung-Chi 
Published: March 2022

Abstract
Background Posttraumatic lymphedema develops more frequently than expected and reports on its management are scarce in the literature. We aimed to report the clinical outcomes of a case series of posttraumatic lymphedema patients treated with different vascularized lymph node transfers (VLNTs).
Patients and Methods Five patients with secondary posttraumatic lower limb lymphedema treated with VLNT were included in this report. The groin-VLNT (n = 1), supraclavicular-VLNT (n = 2), and gastroepiploic-VLNT (n = 2) were implemented. The average flap area was 69.8 cm2. Patients underwent postoperative complex decompressive therapy for an average of 10.0 months.
Results The average mean circumference reduction rate was 24.4% (range, 10.2–37.6%). Postsurgical reduction in the number of infection episodes per year was observed in all patients. The mean follow-up was 34.2 months.
Conclusions VLNT is a promising surgical treatment for posttraumatic lymphedema patients. In our report, VLNT has demonstrated to reduce the volume and number of infections per year in posttraumatic lymphedema.
Flow Cytometric Assessment of Changes in Platelet Reactivity after Acute Coronary Syndrome: A Systematic Review
Authors: Pedersen Oliver Buchhave , Pasalic Leonardo , Nissen Peter H. , Grove Erik Lerkevang , Kristensen Steen Dalby , Hvas Anne-Mette 
Published: March 2022

AbstractIncreased platelet activity is an important predictor for recurrent cardiovascular events in patients with acute coronary syndromes (ACS). Flow cytometry is an advanced method for evaluation of platelet activity. We aimed to summarize the current literature on dynamic changes in platelet activity analyzed by flow cytometry in patients with ACS. Employing the guidelines of Preferred Report Items for Systematic Reviews and Meta-Analyses (PRISMA), we searched PubMed and Embase on October 26, 2021, and identified studies measuring platelet activity with flow cytometry in ACS patients in the acute phase (baseline) and at follow-up in a more stable phase. In the 12 included studies, fibrinogen receptor, α-granule secretion, platelet reactivity index, monocyte-platelet aggregates, neutrophil-platelet aggregates, and reticulated platelets were measured. The fibrinogen receptor and α-granule secretion were either unchanged or lower during follow-up measurements than in the acute phase. Platelet reactivity index showed inconsistent results. Values of monocyte-platelet aggregates and neutrophil-platelet aggregates were lower at follow-up than at baseline (p-values <0.05). Reticulated platelets were either unchanged (p-value >0.64) or lower at 1 to 2 months follow-up (p-value 0.04), and also lower at 5 months to 1-year follow-up (p-value >0.005) compared with baseline. Overall, flow cytometric analyses of platelet function in ACS patients showed that platelet activity was lower at follow-up than at baseline. However, in some patients, platelet activity remained unchanged from baseline to follow-up, possibly indicating a sustained high platelet activity that may increase the risk of recurrent cardiovascular events.
The Severely to Profoundly Hearing-Impaired Population in the United States: Prevalence Estimates and Demographics
Authors: Blanchfield Bonnie B. , Feldman Jacob J. , Dunbar Jennifer L. , Gardner Eric N. 
Published: March 2022

AbstractThis study informs policy makers and third-party payers of the prevalence and characteristics of the severely to profoundly hearing-impaired population in the United States. Nationally representative data were used for estimations in consultation with an expert advisory panel. The prevalence of severe to profound hearing impairment among the US population ranges from 464,000 to 738,000, with 54 percent of this population over age 65 years. Persons with hearing impairment are more likely to be publicly insured, less likely to have private insurance, have lower family incomes, are less educated, and are more likely to be unemployed than the general population. Approximately half a million Americans are severely to profoundly hearing impaired and appear to be more vulnerable, both financially and educationally, as compared to the US population. As a result, access to medical and technological interventions that may assist their hearing loss may be limited.
Abbreviations: NHANES = National Health and Nutrition Examination Survey, NHIS = National Health Interview Survey
Digital micro-photogrammetry in analysis and modeling habit and sectoral structure of real high-pressure high-temperature single-crystal diamonds
Authors: Lytvyn Petro M. , Strelchuk Viktor V. , Nikolenko Andrii S. , Danylenko Ihor M. , Ivakhnenko Serii O. , Kovalenko Tetiana V. , Gontar Oleksandr G. , Malyuta Serhii V. 
Published: March 2022

We demonstrate the potential of using digital stereo micro-photogrammetry for the analysis and modeling of the habit and sectoral structure of real high-pressure high-temperature single-crystal diamonds. A prototype scanning system with a resolution of 5 μm has been implemented based on a digital single-lens reflex camera, making it possible to create highly accurate reproductions of crystal shapes with a minimum size of 4 mm. This method makes it possible to monitor the effect of actual conditions on the physical processes of crystal growth, which is a useful advance for the development of active device elements based on semiconductor diamonds.
Axion as a fuzzy dark matter candidate: proofs in different gauges
Authors: Hwang Jai-chan , Noh Hyerim 
Published: March 2022

Abstract
Axion as a coherently oscillating massive scalar field is known to behave as a zero-pressure irrotational fluid with characteristic quantum stress on a small scale. In relativistic perturbation theory, the case was proved in the axion-comoving gauge up to fully nonlinear and exact order. Our basic assumption is that the field is oscillating with Compton frequency and the Compton wavelength is smaller than the horizon scale. Here, we revisit the relativistic proof to the linear order in the other gauge conditions. We show that the same equation for density perturbation known in the non-relativistic treatment can be derived in two additional gauge conditions: the zero-shear gauge and the uniform-curvature gauge. The uniform-expansion gauge fails to get the aimed equation, and the quantum stress term is missing in the synchronous gauge. For comparison, we present the relativistic density perturbation equations in the zero-pressure fluid in these gauge conditions. Except for the comoving and the synchronous gauge, the equations strikingly differ from the axion case. We clarify that the relativistic analysis based on time averaging is valid for scales larger than the Compton wavelength. Below the Compton wavelength, the field is not oscillating, and our oscillatory ansatz does not apply. We suggest an equation valid in all scales in the comoving gauge. For comparison, we review the non-relativistic quantum hydrodynamics and present the Schrödinger equation to first-order post-Newtonian expansion in the cosmological context.
Scale invariant FIMP miracle
Authors: Barman Basabendu , Ghoshal Anish 
Published: March 2022

Abstract
We study the freeze-in production of vector dark matter (DM) in a classically scale invariant theory, where the Standard Model (SM) is augmented with an abelian U(1)
X
gauge symmetry that is spontaneously broken due to the non-zero vacuum expectation value (VEV) of a scalar charged under the U(1)
X
. Generating the SM Higgs mass at 1-loop level, it leaves only two parameters in the dark sector, namely, the DM mass mX
and the gauge coupling gX
as independent, and supplement with a naturally light dark scalar particle. We show, for gX
~ 𝒪(10-5), it is possible to produce the DM X out-of-equilibrium in the early Universe, satisfying the observed relic abundance for mX
~ 𝒪(TeV), which in turn also determines the scalar mixing angle sinθ ~ 𝒪(10-5). The presence of such naturally light scalar mediator with tiny mixing with the SM,
opens up the possibility for the model to be explored in direct search experiment, which otherwise is insensitive to standard freeze-in scenarios. Moreover we show that even with such feeble couplings, necessary for the DM freeze-in, the scenario is testable in several light dark sector searches (e.g., in DUNE and in FASER-II),
satisfying constraints from the observed relic abundance as well as big bang nucleosynthesis (BBN). Particularly, we find, regions in the parameter space with mX
≳ 1.8 TeV becomes insensitive to direct detection probe but still can be accessible in lifetime frontier searches, again courtesy to the underlying scale invariance of the theory.
Measurements of energy spectra of relativistic electrons and gamma-rays from avalanches developed in the thunderous atmosphere with Aragats Solar Neutron Telescope
Authors: Chilingarian A. , Hovsepyan G. , Karapetyan T. , Sargsyan B. , Chilingaryan S. 
Published: March 2022

Abstract
Aragats solar neutron telescope (ASNT) is a unique
instrument allowing to measure the energy spectra of electrons
accelerated and multiplied in the strong electric fields of the
atmosphere.

We describe the instrument setup, its operation condition, software,
and hardware triggers. We present energy spectra of a very large
thunderstorm ground enhancement (TGE) event observed on 6 October
2021. The detector response function, algorithm to recover energy
spectra from the energy release histograms also are presented. The
spectra recovery procedure is verified by simulation of the response
function of the SEVAN detector, operating nearby ASNT. SEVAN is a
stacked 3 layered detector, interlayered by lead filters registering
both charged and neutral species of cosmic rays. The simulated and
measured count rates of all 3 layers of the SEVAN detector show good
agreement within 20%.
Simulation of a helicon plasma source in a magnetoplasma rocket engine
Authors: YANG Zhenyu , FAN Wei , WEI Jianguo , HAN Xianwei 
Published: March 2022

Abstract
The helicon plasma source, which generates high thrust and high impulse, is of vital importance for magnetoplasma rocket engines. In this work, a multi-component, two-dimensional, axisymmetric fluid model coupled with an electromagnetic field was developed to model the helicon discharge. The simulation results demonstrate that: (i) the discharge mode changes twice—each conversion is accompanied by a plasma density jump and an electron temperature peak in the discharge; (ii) when the input current increases, the plasma density increases, and ionization occurs faster; (iii) the background magnetic field clearly enhances the discharge; (iv) the plasma density may be smaller if the discharge has not entered the wave mode.
Plasma propagation in single-particle packed dielectric barrier discharges: joint effects of particle shape and discharge gap
Authors: ZHU Min , HU Shengyu , ZHANG Yinghao , WU Shuqun , ZHANG Chaohai 
Published: March 2022

Abstract
In this work, a single Al2O3 particle packed dielectric barrier discharge (DBD) reactor with adjustable discharge gap is built, and the influences of the particle shape (ball and column) and the residual gap between the top electrode and particle on the electrical and optical characteristics of plasma are studied. Our research confirms that streamer discharge and surface discharge are the two main discharge patterns in the single-particle packed DBD reactor. The strong electric field distortion at the top of the ball or column caused by the dielectric polarization effect is an important reason for the formation of streamer discharge. The length of streamer discharge is proportional to the size of the residual gap, but the number of discharge times of a single voltage cycle shows an opposite trend. Compared to the column, a smooth spherical surface is more conducive to the formation of large and uniform surface discharges. The surface discharge area and the discharge intensity reach a maximum when the gap is equal to the diameter of the ball. All in all, the results of this study will provide important theoretical support for the establishment of the synergistic characteristics of discharge and catalysis in plasma catalysis.
Harvester ant nest architecture is more strongly affected by intrinsic than extrinsic factors
Authors: O’Fallon Sean , Lowell Eva Sofia Horna , Daniels Doug , Pinter-Wollman Noa 
Published: March 2022

AbstractBehavior is shaped by genes, environment, and evolutionary history in different ways. Nest architecture is an extended phenotype that results from the interaction between the behavior of animals and their environment. Nests built by ants are extended phenotypes that differ in structure among species and among colonies within a species, but the source of these differences remains an open question. To investigate the impact of colony identity (genetics), evolutionary history (species), and the environment on nest architecture, we compared how two species of harvester ants, Pogonomyrmex californicus and Veromessor andrei, construct their nests under different environmental conditions. For each species, we allowed workers from four colonies to excavate nests in environments that differed in temperature and humidity for seven days. We then created casts of each nest to compare nest structures among colonies, between species, and across environmental conditions. We found differences in nest structure among colonies of the same species and between species. Interestingly, however, environmental conditions did not have a strong influence on nest structure in either species. Our results suggest that extended phenotypes are shaped more strongly by internal factors, such as genes and evolutionary history, and are less plastic in response to the abiotic environment, like many physical and physiological phenotypes.
The role of eye-specific attention in ocular dominance plasticity
Authors: Song Fangxing , Lyu Lili , Zhao Jiaxu , Bao Min 
Published: March 2022

AbstractIt is well known how selective attention biases information processing in real time, but few work investigates the aftereffects of prolonged attention, let alone the underlying neural mechanisms. To examine perceptual aftereffect after prolonged attention to a monocular pathway, movie images played normally were presented to normal adult’s one eye (attended eye), while movie images of the same episode but played backwards were presented to the opposite eye (unattended eye). One hour of watching this dichoptic movie caused a shift of perceptual ocular dominance towards the unattended eye. Interestingly, the aftereffect positively correlated with the advantage of neural activity for the attended-eye over unattended-eye signals at the frontal electrodes measured with steady-state visual evoked potentials. Moreover, the aftereffect disappeared when interocular competition was minimized during adaptation. These results suggest that top-down eye-specific attention can induce ocular dominance plasticity through binocular rivalry mechanisms. The present study opens the route to explain at least part of short-term ocular dominance plasticity with the ocular-opponency-neuron model, which may be an interesting complement to the homeostatic compensation theory.
Landscape of Human Immunodeficiency Virus Neutralization Susceptibilities Across Tissue Reservoirs
Authors: Wang Chuangqi , Schlub Timothy E , Yu Wen Han , Tan C Sabrina , Stefic Karl , Gianella Sara , Smith Davey M , Lauffenburger Douglas A , Chaillon Antoine , Julg Boris 
Published: March 2022

Abstract

Background
Human immunodeficiency virus type 1 (HIV-1) sequence diversity and the presence of archived epitope muta­tions in antibody binding sites are a major obstacle for the clinical application of broadly neutralizing antibodies (bNAbs) against HIV-1. Specifically, it is unclear to what degree the viral reservoir is compartmentalized and if virus susceptibility to antibody neutralization differs across tissues.

Methods
The Last Gift cohort enrolled 7 people with HIV diagnosed with a terminal illness and collected antemortem blood and postmortem tissues across 33 anatomical compartments for near full-length env HIV genome sequencing. Using these data, we applied a Bayesian machine-learning model (Markov chain Monte Carlo–support vector machine) that uses HIV-1 envelope sequences and approximated glycan-occupancy information to quantitatively predict the half-maximal inhib­itory concentrations (IC50) of bNAbs, allowing us to map neutralization resistance pattern across tissue reservoirs.

Results
Predicted mean susceptibilities across tissues within participants were relatively homogenous, and the susceptibility pattern observed in blood often matched what was predicted for tissues. However, selected tissues, such as the brain, showed ev­idence of compartmentalized viral populations with distinct neutralization susceptibilities in some participants. Additionally, we found substantial heterogeneity in the range of neutralization susceptibilities across tissues within and between indi­viduals, and between bNAbs within individuals (standard deviation of log2(IC50) &gt;3.4).

Conclusions
Blood-based screening methods to determine viral susceptibility to bNAbs might underestimate the presence of resistant viral variants in tissues. The extent to which these resistant viruses are clinically relevant, that is, lead to bNAb therapeutic failure, needs to be further explored.
Age-Specific Changes in Virulence Associated With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Variants of Concern
Authors: Fisman David N , Tuite Ashleigh R 
Published: March 2022

Abstract

Background
Novel variants of concern (VOCs) have been associated with both increased infectivity and virulence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The virulence of SARS-CoV-2 is closely linked to age. Whether relative increases in virulence of novel VOCs are similar across the age spectrum or are limited to some age groups is unknown.

Methods
We created a retrospective cohort of people in Ontario, Canada, who tested positive for SARS-CoV-2 and were screened for VOCs (n = 259 984) between 7 February 2021 and 31 October 2021. Cases were classified as N501Y-positive VOC, probable Delta VOC, or VOC undetected. We constructed age-specific logistic regression models to evaluate associations between N501Y-postive or Delta VOC infections and infection severity using hospitalization, intensive care unit (ICU) admission, and death as outcome variables. Models were adjusted for sex, comorbidity, vaccination status, and temporal trends.

Results
Infection with either N501Y-positive or Delta VOCs was associated with significant elevations in risk of hospitalization, ICU admission, and death across age groups compared with infections where a VOC was not detected. The Delta VOC increased hospitalization risk in children aged &lt;10 years by a factor of 2.5 (adjusted odds ratio; 95% confidence interval, 1.3 to 5.0) compared with non-VOCs. There was a significant inverse relationship between age and relative increase in risk of death with the Delta VOC, with younger age groups showing a greater relative increase in risk of death than older individuals.

Conclusions
SARS-CoV-2 VOCs appear to be associated with increased relative virulence of infection in all age groups, though low absolute numbers of outcomes in younger individuals make estimates in these groups imprecise.