bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Tracking of Derivative Discontinuities for Delay Fractional Equations Based on Fitted L1 Method
Authors: Cen Dakang , Vong Seakweng 
Published: February 2023

Abstract
In this paper, the analytic solution of the delay fractional model is derived by the method of steps. The theoretical result implies that the regularity of the solution at

s
+

{s^{+}}

is better than that at

0
+

{0^{+}}

, where s is a constant time delay. The behavior of derivative discontinuity is also discussed. Then, improved regularity solution is obtained by the decomposition technique and a fitted

L
⁢
1

{L1}

numerical scheme is designed for it. For the case of initial singularity, the optimal convergence order is reached on uniform meshes when

α
∈

[

2
3

,
1
)

{\alpha\in[\frac{2}{3},1)}

, α is the order of fractional derivative. Furthermore, an improved fitted

L
⁢
1

{L1}

method is proposed and the region of optimal convergence order is larger. For the case

t
>
s

{t>s}

, stability and

min
⁡

{

2
⁢
α

,
1
}

{\min\{2\alpha,1\}}

order convergence of the fitted

L
⁢
1

{L1}

scheme are deduced. At last, the numerical tests are carried out and confirm the theoretical result.
A unified approach to Gelfand and de Vries dualities
Authors: Bezhanishvili Guram , Carai Luca , Morandi Patrick J. , Olberding Bruce 
Published: February 2023

Abstract
We develop a unified approach to Gelfand and de Vries dualities for compact Hausdorff spaces, which is based on appropriate modifications of the classic results of Dieudonné (analysis), Dilworth (lattice theory), and Katětov and Tong (topology)
On fractional integrals generated by Radon transforms over paraboloids
Authors: Rubin Boris 
Published: February 2023

Abstract
We apply the Fourier transform technique and a modified version of E. Stein’s interpolation theorem communicated by L. Grafakos, to obtain sharp

L
p

{L^{p}}

-

L
q

{L^{q}}

estimates for the Radon transform and more general convolution-type fractional integrals with the kernels having singularity on the paraboloids.
On the identification of potential novel therapeutic targets for spinocerebellar ataxia type 1 (SCA1) neurodegenerative disease using EvoPPI3
Authors: Sousa André , Rocha Sara , Vieira Jorge , Reboiro-Jato Miguel , López-Fernández Hugo , Vieira Cristina P. 
Published: February 2023

Abstract
EvoPPI (http://evoppi.i3s.up.pt), a meta-database for protein-protein interactions (PPI), has been upgraded (EvoPPI3) to accept new types of data, namely, PPI from patients, cell lines, and animal models, as well as data from gene modifier experiments, for nine neurodegenerative polyglutamine (polyQ) diseases caused by an abnormal expansion of the polyQ tract. The integration of the different types of data allows users to easily compare them, as here shown for Ataxin-1, the polyQ protein involved in spinocerebellar ataxia type 1 (SCA1) disease. Using all available datasets and the data here obtained for Drosophila melanogaster wt and exp Ataxin-1 mutants (also available at EvoPPI3), we show that, in humans, the Ataxin-1 network is much larger than previously thought (380 interactors), with at least 909 interactors. The functional profiling of the newly identified interactors is similar to the ones already reported in the main PPI databases. 16 out of 909 interactors are putative novel SCA1 therapeutic targets, and all but one are already being studied in the context of this disease. The 16 proteins are mainly involved in binding and catalytic activity (mainly kinase activity), functional features already thought to be important in the SCA1 disease.
Uniqueness of the potential in a time-fractional diffusion equation
Authors: Jing Xiaohua , Peng Jigen 
Published: February 2023

Abstract
This article concerns the uniqueness of an inverse coefficient problem of identifying a spatially varying potential in a one-dimensional time-fractional diffusion equation.
The input sources are given by a complete system in

L
2

⁢

(
0
,
1
)

{L^{2}(0,1)}

, and measurements are observed at the end point of the spatial interval.
Firstly, we provide the positive lower bound of the Green function for the differential operator with different boundary conditions.
Then, based on the positive lower bound estimation of the Green function, the relationship between the Green function,
the solution of the forward problem, and the potential, such measurements uniquely determine the potential on the entire interval under different boundary conditions.
An inverse random source problem for the time-space fractional diffusion equation driven by fractional Brownian motion
Authors: Nie Daxin , Deng Weihua 
Published: February 2023

Abstract
We study the inverse random source problem for the time-space fractional diffusion equation driven by fractional Brownian motion with Hurst index

H
∈

(
0
,
1
)

{H\in(0,1)}

.
With the aid of a novel estimate, by using the operator approach we propose regularity analyses for the direct problem. Then we provide a reconstruction scheme for the source terms f and g up to sign. Next, combining the properties of Mittag-Leffler function, the complete uniqueness and instability analyses are provided. It is worth mentioning that all the analyses are unified for

H
∈

(
0
,
1
)

{H\in(0,1)}

.
Deployment of hybrid FSO/RoF links for 5G heterogeneous networks
Authors: Tamilarasan Ilavarasan , Selvaprabhu Poongundran , Venkatesan Rajeshkumar 
Published: February 2023

Abstract
In this paper, an efficient cognitive algorithm is proposed to support multiple users, more number of services, and devices under any channel conditions. However, the factors like attenuation, signal penetration loss, received power, fading effects, coverage area, bandwidth, and link quality still remains a significant challenge in the real-world applications. A hybrid FSO/RoF with a cognitive algorithm is proposed to overcome the limitations of existing methods. The proposed algorithm assesses the channel conditions based on various parameters and selects the optimum one for transmission. The simulation results confirm that the proposed method can be reliable under any channel conditions and its performance is compared with the existing methods.
Every flight is a surprise: first records of the southern maned three-toed sloth (Bradypus crinitus: Bradypodidae) through drones
Authors: Santos Paloma Marques , Kaizer Mariane da Cruz , Moreira Danielle Oliveira , Melo Fabiano Rodrigues de , Mendes Sérgio Lucena 
Published: February 2023

Abstract
Drones (unmanned aerial vehicles, UAVs), are an advanced technology that allows the collection of large amounts of data in a short amount of time, including the detection of cryptic and arboreal animals. Here, we report the first records of the southern maned sloth Bradypus crinitus obtained with thermal cameras from a drone. As far as we know, this is the first time a sloth has been observed by a drone. We recorded four individuals of B. crinitus in the Brazilian Atlantic Forest, plus first records of Procyon cancrivorus, which were all resting in the forest canopy. The individuals’ thermal responses demonstrate that the use of drones for research on these species may be a viable option to study still unexplored aspects of their ecology or conservation.
Inverse design of high-NA metalens for maskless lithography
Authors: Chung Haejun , Zhang Feng , Li Hao , Miller Owen D. , Smith Henry I. 
Published: February 2023

Abstract
We demonstrate an axisymmetric inverse-designed metalens to improve the performance of zone-plate-array lithography (ZPAL), one of the maskless lithography approaches, that offer a new paradigm for nanoscale research and industry. First, we derive a computational upper bound for a unit-cell-based axisymmetric metalens. Then, we demonstrate a fabrication-compatible inverse-designed metalens with 85.50% transmission normalized focusing efficiency at 0.6 numerical aperture at 405 nm wavelength; a higher efficiency than a theoretical gradient index lens design (79.98%). We also demonstrate experimental validation for our axisymmetric inverse-designed metalens via electron beam lithography. Metalens-based maskless lithography may open a new way of achieving low-cost, large-area nanofabrication.
Panel threshold model with covariate-dependent thresholds and its application to the cash flow/investment relationship
Authors: Yang Lixiong 
Published: February 2023

Abstract
This paper introduces a panel threshold model with covariate-dependent and time-varying thresholds (PTCT), which extends the classical panel threshold model of Hansen, B. E. 1999. “Threshold Effects in Non-dynamic Panels: Estimation, Testing, and Inference.” Journal of Econometrics 93: 345–68 to a framework with multiple covariate-dependent and time-varying thresholds. Based on the within-group transformation and Markov chain Monte Carlo (MCMC) technique, we develop methods for estimation and inference for threshold parameters in the proposed panel threshold model. We also suggest test statistics for threshold effect, threshold constancy, and for determining the number of thresholds. Monte Carlo simulations indicate that the estimation, inference and testing procedures work well in finite samples. Empirically, using the same data as in Hansen, B. E. 1999. “Threshold Effects in Non-dynamic Panels: Estimation, Testing, and Inference.” Journal of Econometrics 93: 345–68 we revisit the cash flow/investment relationship and find quite different results.
In VivoInjection of Anti-LGI1 Antibodies into the Rodent M1 Cortex and Hippocampus Is Ineffective in Inducing Seizures
Authors: Baudin Paul , Roussel Delphine , Mahon Séverine , Charpier Stéphane , Navarro Vincent 
Published: February 2023

AbstractAutoimmune encephalitis (AIE) associated with antibodies directed against the leucine-rich glioma inactivated 1 (LGI1) protein is the second most common AIE and is responsible for deleterious neocortical and limbic epileptic seizures. Previous studies demonstrated a pathogenic role of anti-LGI1 antibodies via alterations in the expression and function of Kv1 channels and AMPA receptors. However, the causal link between antibodies and epileptic seizures has never been demonstrated. Here, we attempted to determine the role of human anti-LGI1 autoantibodies in the genesis of seizures by analyzing the impact of their intracerebral injection in rodents. Acute and chronic injections were performed in rats and mice in the hippocampus and primary motor cortex, the two main brain regions affected by the disease. Acute infusion of CSF or serum IgG of anti-LGI1 AIE patients did not lead to the emergence of epileptic activities, as assessed by multisite electrophysiological recordings over a 10 h period after injection. A chronic 14 d injection, coupled with continuous video-EEG monitoring, was not more effective. Overall, these results demonstrate that acute and chronic injections of CSF or purified IgG from LGI1 patients are not able to generate epileptic activity by themselves in the different animal models tested.
Executive Control of Sequence Behavior in Pigeons Involves Two Distinct Brain Regions
Authors: Hahn Lukas Alexander , Rose Jonas 
Published: February 2023

AbstractExecutive functions arise from multiple regions of the brain acting in concert. To facilitate such cross-regional computations, the brain is organized into distinct executive networks, like the frontoparietal network. Despite similar cognitive abilities across many domains, little is known about such executive networks in birds. Recent advances in avian fMRI have shown a possible subset of regions, including the nidopallium caudolaterale (NCL) and the lateral part of medial intermediate nidopallium (NIML), that may contribute to complex cognition, forming an action control system of pigeons. We investigated the neuronal activity of NCL and NIML. Single-cell recordings were obtained during the execution of a complex sequential motor task that required executive control to stop executing one behavior and continue with a different one. We compared the neuronal activity of NIML to NCL and found that both regions fully processed the ongoing sequential execution of the task. Differences arose from how behavioral outcome was processed. Our results indicate that NCL takes on a role in evaluating outcome, while NIML is more tightly associated with ongoing sequential steps. Importantly, both regions seem to contribute to overall behavioral output as parts of a possible avian executive network, crucial for behavioral flexibility and decision-making.
Multielectrode Cortical Stimulation Selectively Induces Unidirectional Wave Propagation of Excitatory Neuronal Activity in Biophysical Neural Model
Authors: Halgren Alma S. , Siegel Zarek , Golden Ryan , Bazhenov Maxim 
Published: February 2023

Cortical stimulation is emerging as an experimental tool in basic research and a promising therapy for a range of neuropsychiatric conditions. As multielectrode arrays enter clinical practice, the possibility of using spatiotemporal patterns of electrical stimulation to induce desired physiological patterns has become theoretically possible, but in practice can only be implemented by trial-and-error because of a lack of predictive models. Experimental evidence increasingly establishes traveling waves as fundamental to cortical information-processing, but we lack an understanding of how to control wave properties despite rapidly improving technologies. This study uses a hybrid biophysical-anatomical and neural-computational model to predict and understand how a simple pattern of cortical surface stimulation could induce directional traveling waves via asymmetric activation of inhibitory interneurons. We found that pyramidal cells and basket cells are highly activated by the anodal electrode and minimally activated by the cathodal electrodes, while Martinotti cells are moderately activated by both electrodes but exhibit a slight preference for cathodal stimulation. Network model simulations found that this asymmetrical activation results in a traveling wave in superficial excitatory cells that propagates unidirectionally away from the electrode array. Our study reveals how asymmetric electrical stimulation can easily facilitate traveling waves by relying on two distinct types of inhibitory interneuron activity to shape and sustain the spatiotemporal dynamics of endogenous local circuit mechanisms.SIGNIFICANCE STATEMENTElectrical brain stimulation is becoming increasingly useful to probe the workings of brain and to treat a variety of neuropsychiatric disorders. However, stimulation is currently performed in a trial-and-error fashion as there are no methods to predict how different electrode arrangements and stimulation paradigms will affect brain functioning. In this study, we demonstrate a hybrid modeling approach, which makes experimentally testable predictions that bridge the gap between the microscale effects of multielectrode stimulation and the resultant circuit dynamics at the mesoscale. Our results show how custom stimulation paradigms can induce predictable, persistent changes in brain activity, which has the potential to restore normal brain function and become a powerful therapy for neurological and psychiatric conditions.
Inducible CRISPR Epigenome Systems Mimic Cocaine Induced Bidirectional Regulation of Nab2 and Egr3
Authors: Choi Eric Y. , Franco Daniela , Stapf Catherine A. , Gordin Madeleine , Chow Amanda , Cover Kara K. , Chandra Ramesh , Lobo Mary Kay 
Published: February 2023

Substance use disorder is a chronic disease and a leading cause of disability around the world. The NAc is a major brain hub mediating reward behavior. Studies demonstrate exposure to cocaine is associated with molecular and functional imbalance in NAc medium spiny neuron subtypes (MSNs), dopamine receptor 1 and 2 enriched D1-MSNs and D2-MSNs. We previously reported repeated cocaine exposure induced transcription factor early growth response 3 (Egr3) mRNA in NAc D1-MSNs, and reduced it in D2-MSNs. Here, we report our findings of repeated cocaine exposure in male mice inducing MSN subtype-specific bidirectional expression of theEgr3corepressor NGFI-A-binding protein 2 (Nab2). Using CRISPR activation and interference (CRISPRa and CRISPRi) tools combined withNab2orEgr3-targeted sgRNAs, we mimicked these bidirectional changes in Neuro2a cells. Furthermore, we investigated D1-MSN- and D2-MSN-specific expressional changes of histone lysine demethylasesKdm1a,Kdm6a, andKdm5cin NAc after repeated cocaine exposure in male mice. SinceKdm1ashowed bidirectional expression patterns in D1-MSNs and D2-MSNs, likeEgr3, we developed a light-inducible Opto-CRISPR-KDM1a system. We were able to downregulateEgr3andNab2transcripts in Neuro2A cells and cause similar bidirectional expression changes we observed in D1-MSNs and D2-MSNs of mouse repeated cocaine exposure model. Contrastingly, our Opto-CRISPR-p300 activation system induced theEgr3andNab2transcripts and caused opposite bidirectional transcription regulations. Our study sheds light on the expression patterns ofNab2andEgr3in specific NAc MSNs in cocaine action and uses CRISPR tools to further mimic these expression patterns.SIGNIFICANCE STATEMENTSubstance use disorder is a major societal issue. The lack of medication to treat cocaine addiction desperately calls for a treatment development based on precise understanding of molecular mechanisms underlying cocaine addiction. In this study, we show thatEgr3andNab2are bidirectionally regulated in mouse NAc D1-MSNs and D2-MSNs after repeated exposure to cocaine. Furthermore, histone lysine demethylations enzymes with putative EGR3 binding sites showed bidirectional regulation in D1- and D2-MSNs after repeated exposure to cocaine. Using Cre- and light-inducible CRISPR tools, we show that we can mimic this bidirectional regulation ofEgr3andNab2in Neuro2a cells.
Voltage to Calcium Transformation Enhances Direction Selectivity inDrosophilaT4 Neurons
Authors: Mishra Abhishek , Serbe-Kamp Etienne , Borst Alexander , Haag Juergen 
Published: February 2023

An important step in neural information processing is the transformation of membrane voltage into calcium signals leading to transmitter release. However, the effect of voltage to calcium transformation on neural responses to different sensory stimuli is not well understood. Here, we use in vivo two-photon imaging of genetically encoded voltage and calcium indicators, ArcLight and GCaMP6f, respectively, to measure responses in direction-selective T4 neurons of femaleDrosophila. Comparison between ArcLight and GCaMP6f signals reveals calcium signals to have a significantly higher direction selectivity compared with voltage signals. Using these recordings, we build a model which transforms T4 voltage responses into calcium responses. Using a cascade of thresholding, temporal filtering and a stationary nonlinearity, the model reproduces experimentally measured calcium responses across different visual stimuli. These findings provide a mechanistic underpinning of the voltage to calcium transformation and show how this processing step, in addition to synaptic mechanisms on the dendrites of T4 cells, enhances direction selectivity in the output signal of T4 neurons. Measuring the directional tuning of postsynaptic vertical system (VS)-cells with inputs from other cells blocked, we found that, indeed, it matches the one of the calcium signal in presynaptic T4 cells.SIGNIFICANCE STATEMENTThe transformation of voltage to calcium influx is an important step in the signaling cascade within a nerve cell. While this process has been intensely studied in the context of transmitter release mechanism, its consequences for information transmission and neural computation are unclear. Here, we measured both membrane voltage and cytosolic calcium levels in direction-selective cells ofDrosophilain response to a large set of visual stimuli. We found direction selectivity in the calcium signal to be significantly enhanced compared with membrane voltage through a nonlinear transformation of voltage to calcium. Our findings highlight the importance of an additional step in the signaling cascade for information processing within single nerve cells.
How to Salvage Democracy: A Reading
Authors: Atanassow Ewa 
Published: February 2023

Francis Fukuyama, Liberalism and Its Discontents (New York: Farrar, Straus and Giroux, 2022)
Stein Ringen, How Democracies Live: Power, Statecraft, and Freedom in Modern Societies (Chicago: University of Chicago Press, 2022)
Reviewing two recent books, Francis Fukuyama’s Liberalism and Its Discontents and Stein Ringen’s How Democracies Live: Power, Statecraft, and Freedom in Modern Societies, this article explores their respective diagnoses of the current crisis of democracy and their proposed solutions. It shows that, while similar in method and intent, the two works diverge on crucial analytical and policy issues. By putting them in conversation, and bringing out these telling differences, the article seeks to clarify the urgent questions that face Western democracies today and the challenges of addressing them.
The eukaryotic translation initiation factor eIF4E reprograms alternative splicing
Authors: Ghram Mehdi , Morris Gavin , Culjkovic‐Kraljacic Biljana , Mars Jean‐Clement , Gendron Patrick , Skrabanek Lucy , Revuelta Maria Victoria , Cerchietti Leandro , Guzman Monica L , Borden Katherine L B 
Published: February 2023

AbstractAberrant splicing is typically attributed to splice‐factor (SF) mutation and contributes to malignancies including acute myeloid leukemia (AML). Here, we discovered a mutation‐independent means to extensively reprogram alternative splicing (AS). We showed that the dysregulated expression of eukaryotic translation initiation factor eIF4E elevated selective splice‐factor production, thereby impacting multiple spliceosome complexes, including factors mutated in AML such as SF3B1 and U2AF1. These changes generated a splicing landscape that predominantly supported altered splice‐site selection for ~800 transcripts in cell lines and ~4,600 transcripts in specimens from high‐eIF4E AML patients otherwise harboring no known SF mutations. Nuclear RNA immunoprecipitations, export assays, polysome analyses, and mutational studies together revealed that eIF4E primarily increased SF production via its nuclear RNA export activity. By contrast, eIF4E dysregulation did not induce known SF mutations or alter spliceosome number. eIF4E interacted with the spliceosome and some pre‐mRNAs, suggesting its direct involvement in specific splicing events. eIF4E induced simultaneous effects on numerous SF proteins, resulting in a much larger range of splicing alterations than in the case of mutation or dysregulation of individual SFs and providing a novel paradigm for splicing control and dysregulation.