bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical Properties of Thermoplastic Cornstarch/Hibiscus sabdariffa Fiber Obtained by Evaporation Casting
Authors: Ortuño‐López Mónica B. , Salazar‐Cruz Beatriz A. , del Real Alicia , Almendarez‐Camarillo Armando , López‐Barroso Juventino , Rivera‐Armenta José L. , Flores‐Hernández Cynthia G. 
Published: March 2023

AbstractHibiscus sabdariffa is a typical ingredient in a popular Mexican beverage, and a lot of waste is produced as a result. The fibers obtained from Hibiscus sabdariffa waste can be used as reinforcement in a natural composite. This research evaluates the influence and effect of different properties of fiber incorporated into a cornstarch matrix. The mechanical and thermomechanical performance is evaluated using tensile measurements and dynamic mechanical analysis. Thermal stability is analyzed by thermogravimetric analysis. The micrographics show a good incorporation of the bioreinforcement into the polymer matrix. The tensile measurements show that the fiber can be related to a slight decrease in Young´s modulus. The dynamic mechanical analysis results show that the composite with 4 wt% of reinforcement has a higher storage modulus (1139 MPa at 50 °C) than the starch matrix (854 MPa at −50 °C). According to the thermal stability of the composites is displaced to lower temperatures, which can suggest an effect of biodegradation acquired with the progressive addition of the biofibers. As a result, the composites obtained have been shown to be sustainable and friendly to the environment, and the films can offer an advantage for packaging‐type bags for foods.
Experimenting at an outreach science lab versus at school—Differences in students' basic need satisfaction, intrinsic motivation, and flow experience
Authors: Kirchhoff Tim , Randler Christoph , Großmann Nadine 
Published: March 2023

AbstractAll over the world, educational science outreach programs in which students can perform laboratory work have been developed. A common goal of these programs is to counteract students' decreasing motivation in STEM education. In Germany, several outreach science labs have been established over the last 20 years. It is assumed that the characteristics of these labs foster students' basic need satisfaction and qualities of motivation such as intrinsic motivation and flow. However, research in this field often lacks comparisons of motivation between the learning environmentsoutreach science labandschool. Thus, the current study investigated students' perceived need satisfaction (relatedness, competence, and autonomy), intrinsic motivation, and flow experience during experimentation at an outreach science lab (n = 231) and at school (n = 203). We found that experimentation in the two different learning environments resulted in a comparable degree of perceived autonomy and intrinsic motivation. However, differences in perceived relatedness, competence, and flow experience were found in favor of the students who experimented at the lab. Thus, visiting outreach science labs is especially beneficial for students' perception of relatedness, effectiveness, and enjoyment during experimentation.
Ion Polarimetry
Authors: Schmidke William 
Published: March 2023

AbstractThe degree of polarization of the beams must be precisely measured, both to enable development and optimization of the beams, and to normalize the spin dependent effects observed in experiments. Ion beam polarimetry is particularly challenging since the physics processes available for polarimetry are themselves the subject of active physics research. This chapter describes ion polarimetry as implemented at the Relativistic Heavy Ion Collider (RHIC), the only high energy polarized proton collider.
Introduction
Authors: Niohuru Ilha 
Published: March 2023

AbstractThere is an acute scarcity of research and studies on the conditions of healthcare in African countries. According to Marincola and Kariuki (2020), 20% of the global disease burden falls on the shoulders of Africa, yet only 1% of worldwide scientific output focuses on African countries. Filling the epistemological gap is critical, for it will not only shine a light on our understanding of the realities of the continent, but also pave way for more engaged future studies. The investigation of existing healthcare conditions in Africa provides an indispensable basis for generating educated responses to the challenges that confront the continent as a whole and across its different localities.
Twist-four gravitational form factor at NNLO QCD from trace anomaly constraints
Authors: Tanaka Kazuhiro 
Published: March 2023

Abstract
It is known that the trace anomaly in the QCD energy-momentum tensor Tμν can be attributed to the anomalies for each of the gauge-invariant quark part and gluon part of Tμν, and their explicit three-loop formulas have been derived in the $$ \overline{\textrm{MS}} $$

MS
¯

scheme in the dimensional regularization. The matrix elements of this quark/gluon decomposition of the QCD trace anomaly allow us to derive the QCD constraints on the hadron’s gravitational form factors, in particular, on the twist-four gravitational form factor, $$ {\overline{C}}_{q,g} $$

C
¯

q
,
g

. Using the three-loop quark/gluon trace anomaly formulas, we calculate the forward (zero momentum transfer) value of the twist-four gravitational form factor $$ {\overline{C}}_{q,g} $$

C
¯

q
,
g

at the next-to-next-to-leading-order (NNLO) accuracy. We present quantitative results for nucleon as well as for pion, leading to a model-independent determination of the forward value of $$ {\overline{C}}_{q,g} $$

C
¯

q
,
g

. We find quite different pattern in the obtained results between the nucleon and the pion. In particular, for the nucleon, the present information from experiment and lattice QCD on the nonperturbative matrix elements arising in our NNLO formula allows us to obtain a prediction of the forward value of $$ {\overline{C}}_{q,g} $$

C
¯

q
,
g

at the accuracy of a few percent level.
Gravitational transition form factors of N → ∆ via QCD light-cone sum rules
Authors: Özdem U. , Azizi K. 
Published: March 2023

Abstract
We present the first direct calculation on the gravitational form factors (GFFs) of the N → ∆ transition using an analytic method, the QCD light-cone sum rules. The matrix element of the quark part of the energy momentum tensor current sandwiched between the nucleon and ∆ states are parameterized in terms of five independent conserved and four independent non-conserved GFFs, for calculation of which we use the distribution amplitudes (DAs) of the on-shell nucleon expanded in terms of functions with different twists. We present the results for two sets of light-cone input parameters. The results indicate that the behavior of the form factors with respect to Q2 are described by multipole fit functions. Our results may be checked by other phenomenological models including the Lattice QCD as well as future related experiments.
Quasi-topological gravities on general spherically symmetric metric
Authors: Chen Feiyu 
Published: March 2023

Abstract
In this work we study a more restricted class of quasi-topological gravity theories where the higher curvature terms have no contribution to the equation of motion on general static spherically symmetric metric where gttgrr ≠ constant. We construct such theories up to quintic order in Riemann tensor and observe an important property of these theories: the higher order term in the Lagrangian vanishes identically when evaluated on the most general non-stationary spherically symmetric metric ansatz. This not only signals the higher terms could only have non-trivial effects when considering perturbations, but also makes the theories quasi-topological on a much wider range of metrics. As an example of the holographic effects of such theories, we consider a general Einstein-scalar theory and calculate it’s holographic shear viscosity.
Infinite distances in multicritical CFTs and higher-spin holography
Authors: Basile Ivano , Campoleoni Andrea , Pekar Simon , Skvortsov Evgeny 
Published: March 2023

Abstract
We investigate the swampland distance conjecture in higher-spin gravity. To this end, we study multicritical generalizations of large-N vector models, bosonic and fermionic, and we compute the quantum information distance along selected renormalization-group trajectories toward the higher-spin limit. In contrast to the expected exponential decay of higher-spin masses or anomalous dimensions, we find that infinite-distance limits in these models lead to a power-like decay. This suggests that stringy exponential decays are characteristic of matrix-like gauge theories, rather than vector models. We corroborate this notion studying the information distance along coupling variations in Chern-Simons-matter CFTs, where matrix-like degrees of freedom dominate over vector-like ones.
Machine learning-based jet and event classification at the Electron-Ion Collider with applications to hadron structure and spin physics
Authors: Lee Kyle , Mulligan James , Płoskoń Mateusz , Ringer Felix , Yuan Feng 
Published: March 2023

Abstract
We explore machine learning-based jet and event identification at the future Electron-Ion Collider (EIC). We study the effectiveness of machine learning-based classifiers at relatively low EIC energies, focusing on (i) identifying the flavor of the jet and (ii) identifying the underlying hard process of the event. We propose applications of our machine learning-based jet identification in the key research areas at the future EIC and current Relativistic Heavy Ion Collider program, including enhancing constraints on (transverse momentum dependent) parton distribution functions, improving experimental access to transverse spin asymmetries, studying photon structure, and quantifying the modification of hadrons and jets in the cold nuclear matter environment in electron-nucleus collisions. We establish first benchmarks and contrast the estimated performance of flavor tagging at the EIC with that at the Large Hadron Collider. We perform studies relevant to aspects of detector design including particle identification, charge information, and minimum transverse momentum capabilities. Additionally, we study the impact of using full event information instead of using only information associated with the identified jet. These methods can be deployed either on suitably accurate Monte Carlo event generators, or, for several applications, directly on experimental data. We provide an outlook for ultimately connecting these machine learning-based methods with first principles calculations in quantum chromodynamics.
Entanglement dynamics of the non-unitary holographic channel
Authors: Goto Kanato , Nozaki Masahiro , Tamaoka Kotaro , Tan Mao Tian 
Published: March 2023

AbstractWe study the dynamical properties of a strongly scrambling quantum circuit involving a projective measurement on a finite-sized region by studying the operator entanglement entropy and mutual information (OEE and BOMI) of the dual operator state that corresponds to this quantum circuit. The time-dependence of the OEE exhibits a new dynamical behavior of operator entanglement, namely an additional fractional coefficient that accompanies the linear time growth of the OEE. For a holographic system, this is equivalent to an additional fractional coefficient that modifies the linear growth rate of the wormhole volume. The time-dependence of the BOMI shows that the projective measurement may destroy the non-local correlations in this dual state. We also propose a gravity dual as well as a line-tension picture, which is an effective model, that describe this strongly scrambling quantum circuit.
Constraints on ultralight scalar dark matter with quadratic couplings
Authors: Bouley Thomas , Sørensen Philip , Yu Tien-Tien 
Published: March 2023

Abstract
Ultralight dark matter is a compelling dark matter candidate. In this work, we examine the impact of quadratically-coupled ultralight dark matter on the predictions of Big Bang Nucleosynthesis. The presence of ultralight dark matter can modify the effective values of fundamental constants during Big Bang Nucleosynthesis, modifying the predicted abundances of the primordial elements such as Helium-4. We improve upon the existing literature in two ways: firstly, we take into account the thermal mass acquired by the ultralight dark matter due to its quadratic interactions with the Standard Model bath, which affects the cosmological evolution of the dark matter. Secondly, we treat the weak freeze-out using the full kinetic equations instead of using an instantaneous approximation. Both improvements were shown to impact the Helium-4 prediction in the context of universally-coupled dark matter in previous work. We extend these lessons to more general couplings. We show that with these modifications, Big Bang Nucleosynthesis provides strong constraints of ultralight dark matter with quadratic couplings to the Standard Model for a large range of masses as compared to other probes of this model, such as equivalence principle tests, atomic and nuclear clocks, as well as astrophysical and other cosmological probes.
Absence of operator growth for average equal-time observables in charge-conserved sectors of the Sachdev-Ye-Kitaev model
Authors: Paviglianiti Alessio , Bandyopadhyay Soumik , Uhrich Philipp , Hauke Philipp 
Published: March 2023

Abstract
Quantum scrambling plays an important role in understanding thermalization in closed quantum systems. By this effect, quantum information spreads throughout the system and becomes hidden in the form of non-local correlations. Alternatively, it can be described in terms of the increase in complexity and spatial support of operators in the Heisenberg picture, a phenomenon known as operator growth. In this work, we study the disordered fully-connected Sachdev-Ye-Kitaev (SYK) model, and we demonstrate that scrambling is absent for disorder-averaged expectation values of observables. In detail, we adopt a formalism typical of open quantum systems to show that, on average and within charge-conserved sectors, operators evolve in a relatively simple way which is governed by their operator size. This feature only affects single-time correlation functions, and in particular it does not hold for out-of-time-order correlators, which are well-known to show scrambling behavior. Making use of these findings, we develop a cumulant expansion approach to approximate the evolution of equal-time observables. We employ this scheme to obtain analytic results that apply to arbitrary system size, and we benchmark its effectiveness by exact numerics. Our findings shed light on the structure of the dynamics of observables in the SYK model, and provide an approximate numerical description that overcomes the limitation to small systems of standard methods.
NNLO QCD corrections to event shapes at the LHC
Authors: Alvarez Manuel , Cantero Josu , Czakon Michal , Llorente Javier , Mitov Alexander , Poncelet Rene 
Published: March 2023

Abstract
In this work we perform the first ever calculation of jet event shapes at hadron colliders at next-to-next-to leading order (NNLO) in QCD. The inclusion of higher order corrections removes the shape difference observed between data and next-to-leading order predictions. The theory uncertainty at NNLO is comparable to, or slightly larger than, existing measurements. Except for narrow kinematical ranges where all-order resummation becomes important, the NNLO predictions for the event shapes considered in the present work are reliable. As a prime application of the results derived in this work we provide a detailed investigation of the prospects for the precision determination of the strong coupling constant and its running through TeV scales from LHC data.
Search for exotic decays of the Higgs boson into long-lived particles with jet pairs in the final state at CLIC
Authors: Kucharczyk Marcin , Goncerz Mateusz 
Published: March 2023

Abstract
A study of the sensitivity of the CLIC_ILD detector model for massive long-lived particles produced in the decay of the Higgs boson is presented, using a data sample of e+e− collisions at $$ \sqrt{\textrm{s}} $$

s

= 350 GeV and $$ \sqrt{\textrm{s}} $$

s

= 3 TeV, corresponding to an integrated luminosity of 1 ab−1 and 3 ab−1, respectively. The sensitivity range covers long-lived particle lifetimes from 1 to 300 ps, masses between 25 and 50 GeV/c2, and a parent Higgs mass of 126 GeV/c2. Sensitivities to the production cross-section as a function of the long-lived-particle mass and lifetime are determined.
Universal spinning Casimir equations and their solutions
Authors: Burić Ilija , Schomerus Volker 
Published: March 2023

Abstract
Conformal blocks are a central analytic tool for higher dimensional conformal field theory. We employ Harish-Chandra’s radial component map to construct universal Casimir differential equations for spinning conformal blocks in any dimension d of Euclidean space. Furthermore, we also build a set of differential “shifting” operators that allow to construct solutions of the Casimir equations from certain seeds. In the context of spinning four-point blocks of bulk conformal field theory, our formulas provide an elegant and far reaching generalisation of existing expressions to arbitrary tensor fields and arbitrary dimension d. The power of our new universal approach to spinning blocks is further illustrated through applications to defect conformal field theory. In the case of defects of co-dimension q = 2 we are able to construct conformal blocks for two-point functions of symmetric traceless bulk tensor fields in both the defect and the bulk channel. This opens an interesting avenue for applications to the defect bootstrap. Finally, we also derive the Casimir equations for bulk-bulk-defect three-point functions in the bulk channel.
Hadamard Products of Symbolic Powers and Hadamard Fat Grids
Authors: Bahmani Jafarloo I. , Bocci C. , Guardo E. , Malara G. 
Published: March 2023

AbstractIn this paper we address the question if, for points $$P, Q \in \mathbb {P}^{2}$$

P
,
Q
∈

P

2

, $$I(P)^{m} \star I(Q)^{n}=I(P \star Q)^{m+n-1}$$

I

(
P
)

m

⋆
I

(
Q
)

n

=
I

(
P
⋆
Q
)

m
+
n
-
1

and we obtain different results according to the number of zero coordinates in P and Q. Successively, we use our results to define the so called Hadamard fat grids, which are the result of the Hadamard product of two sets of collinear points with given multiplicities. The most important invariants of Hadamard fat grids, as minimal resolution, Waldschmidt constant and resurgence, are then computed.
Endogenous but not sensory-driven activity controls migration, morphogenesis and survival of adult-born juxtaglomerular neurons in the mouse olfactory bulb
Authors: Li Kaizhen , Figarella Katherine , Su Xin , Kovalchuk Yury , Gorzolka Jessika , Neher Jonas J. , Mojtahedi Nima , Casadei Nicolas , Hedrich Ulrike B. S. , Garaschuk Olga 
Published: March 2023

AbstractThe development and survival of adult-born neurons are believed to be driven by sensory signaling. Here, in vivo analyses of motility, morphology and Ca2+ signaling, as well as transcriptome analyses of adult-born juxtaglomerular cells with reduced endogenous excitability (via cell-specific overexpression of either Kv1.2 or Kir2.1 K+ channels), revealed a pronounced impairment of migration, morphogenesis, survival, and functional integration of these cells into the mouse olfactory bulb, accompanied by a reduction in cytosolic Ca2+ fluctuations, phosphorylation of CREB and pCREB-mediated gene expression. Moreover, K+ channel overexpression strongly downregulated genes involved in neuronal migration, differentiation, and morphogenesis and upregulated apoptosis-related genes, thus locking adult-born cells in an immature and vulnerable state. Surprisingly, cells deprived of sensory-driven activity developed normally. Together, the data reveal signaling pathways connecting the endogenous intermittent neuronal activity/Ca2+ fluctuations as well as enhanced Kv1.2/Kir2.1 K+ channel function to migration, maturation, and survival of adult-born neurons.
Influence of a prolonged shelf time on PA12 laser sintering powder and resulting part properties
Authors: Klippstein Sven Helge , Kletetzka Ivo , Sural Ilknur , Schmid Hans-Joachim 
Published: March 2023

AbstractIn the laser sintering technology, the semi-crystalline polymer material is exposed to elevated temperatures during processing, which leads to serious material ageing for most materials. This has already been investigated intensively by various authors. However, the ageing of the material at ambient temperatures during shelf life has not been the focus so far. The need to analyse the shelf life can be derived from an ecological and economic point of view. This work is focusing on the shelf life of PA2200 (PA12). To reduce the potential influences of powder production fluctuations, two different powder batches stored for 5.5 years and 6.5 years are investigated and compared to a reference powder produced 0.5 years before these investigations. Multiple powder analyses and part characterisations have been performed. A significant yellowing and molecular chain length reduction can be derived from the measurement results. Whereas the influence on mechanical part performance was minor, the parts built with the stored powders are more yellowish. As it is most likely that this is due to the consumption of polyamide stabilisers, it can be assumed that these parts will be subject to significantly faster ageing. Therefore, it is still not recommended to use the stored powders for critical parts or light intense and humid environments.
Hot working behaviour of low-cost Ti-3.4Fe bio-implant alloy
Authors: Mosoma Dineo , Klenam Desmond , Maunganidze Takunda , Bodunrin Michael 
Published: March 2023

AbstractThis study investigated the hot workability of an experimental, non-toxic, low-cost Ti-3.4Fe alloy using flow stress analysis, constitutive modelling, processing maps and microstructural examination. Hot compression tests were performed on Ti-3.4Fe alloy samples at different deformation temperatures (750, 800, 850 and 900 °C), strain rates (0.05, 0.1, 1 and 10 s−1) and a total strain of 0.6. The compression tests were performed using a Gleeble® 3500 thermomechanical simulator. The isothermally compressed samples were analysed using a scanning electron microscope to assess the microstructure. An Arrhenius-based model was used to derive the constitutive constants. From the results, the stress exponent and activation energy were 4.91 and 611 kJ.mol−1 under the steady-state stress condition and 5.32 and 675 kJ.mol−1 at peak stress. The stress exponents suggested a dislocation climb and glide mechanism controlling deformation. The processing map showed that the optimum conditions to deform Ti-3.4Fe were 850 °C at a strain rate of 0.1 s−1 for both steady-state and peak stresses. The microstructure revealed kinked, rotated and bent lamella at the safe region (850 °C at 0.05 s−1), confirming the dominance of dynamic recovery as the softening mechanism. Instabilities manifested as cracks and inhomogeneity at 750 °C and 1 s−1 and at 850 °C and 10 s−1.