bluuebunny/crossref_metadata_2025 huggingface dataset:
Therapy dogs, stress-reduction, and well-being within the detachment: Interviews with law-enforcement personnel
Authors: Green Freya L.L. , Binfet John-Tyler
Published: October 2022

Despite the increasing popularity of canine-assisted interventions (CAIs) across a variety of contexts, and the demonstrated efficacy they have on stress reduction, there is a paucity of research exploring the implementation of such programs within the context of law enforcement. Policing is known to be an environment in which personnel experience elevated occupational stress. As stress can compromise the overall well-being of law-enforcement personnel and their ability to serve the public, it is important to understand how CAIs involving therapy dog visitation are experienced by the very individuals for whom they are intended to help. This qualitative study explored Royal Canadian Mounted Police (RCMP) members’ experiences of stress within a detachment and their perceptions of a CAI integrated within their workplace to support their well-being. Eight RCMP members (75% female, Mage = 49.21,
SD
= 6.12) from an urban RCMP detachment situated in the downtown core of a small city were interviewed. The interview focused on topics including members’ experiences of stress within the workplace, their perceptions of the effects of stress, resources and sources of support, and their experiences participating in a weekly CAI within their detachment. Results indicated that organizational stressors were identified more often than operational stressors; that members most commonly reported that stress rendered them more irritable and impacted their sleep, and that the most commonly reported coping mechanism and resource are exercise and medical services, respectively. In discussing the CAI, participants were overwhelmingly positive in their experiences of the program, and demonstrated support for having CAIs within the detachment setting. Discussion of the impact of the sessions demonstrated that participants found that the program served as a break from work, relieved their stress, improved their mood, and helped them to change perspectives. Participants also identified the role of the dogs within the program, which included their role as a social being. The findings from the current study contribute to better understanding of the lived experiences of stress within RCMP members and of CAIs within an applied setting.
Veterinary professionals’ experiences with human caregivers when providing animal hospice and palliative care
Authors: Hoffmann Heath C. , Dickinson George E.
Published: October 2022

A significant role in veterinary medical practices is the provision of end-of-life (EOL) care to pets and their clients. Yet, U.S. veterinarians report being dissatisfied with the level of training they receive on EOL issues in their veterinary medical programs (
Dickinson et al., 2011
). At the same time, the ubiquity of veterinary information on the Internet (e.g., “Dr. Google”) has the potential for instilling pet owners with a false sense of expertise that veterinarians must then negotiate when providing EOL care. In this context, we surveyed 86 veterinary members of the International Association for Animal Hospice and Palliative Care (IAAHPC) to explore whether and/or how veterinary medical information clients obtain from the Internet impacts the veterinarians’ delivery of EOL care to those clients’ pets; we similarly investigate the information that veterinarians prefer their clients knew before meeting with them to provide EOL care. In light of the inherent challenges of EOL veterinary care outlined above, we learn from veterinarians what they feel are the most challenging and rewarding aspects of providing palliative and hospice care. Using qualitative thematic coding, our results show, in sum, that veterinary information from the Internet is both helpful and harmful to veterinarian interactions with clients; veterinarians wished clients understood the value of hospice and palliative care as an EOL care option and that grief is normal; and veterinarians report a most positive aspect of dealing with these issues is the gratitude clients show for helping their pets die peacefully.
A Logic Model of a Dementia-specific Program of Equine-assisted Activities
Authors: Lassell Rebecca , Fields Beth , Busselman Sarah , Hempel Tauren , Wood Wendy
Published: October 2022

Insufficient descriptions of
what
comprises animal-assisted interventions and
why
and
how
they are presumed to work pose significant challenges to their replication and further scientific development. The purpose of this study was to construct a comprehensive research-based logic model describing a promising program of equine-assisted activities for older adults with Alzheimer’s disease and related dementias. Logic models can advance scientific development of innovative programs by elucidating their critical elements. Employing the qualitative method of directed content analysis, we conducted secondary analyses of previously collected interviews of five providers and fieldnotes of each programmatic session. Employing quantitative direct observational methods, we conducted secondary analysis of eight previously collected hour-long videotapes of four older adults with dementia during the program. The resulting logic model from our secondary analysis of mixed methods data elucidated the program’s purpose, assumptions, programmatic activities, and outcomes, plus congruent linkages across these elements. These findings can guide replication of the program in multiple research and practice contexts and support its future scientific development. Next research steps include evaluating short- and long-term outcomes beyond participants’ direct experiences of the program, clarifying the program’s optimal dosages, and ensuring fidelity of its implementation. This logic model may also help to inform scientific development of other animal-assisted interventions.
Human-Animal Co-sleeping Practices among Australian Dog Owners
Authors: Hoffman Christy L. , Hazelton Peta C. , Smith Bradley P.
Published: October 2022

Human-animal co-sleeping is relatively common among dog owners; however, the nature of this practice is not well understood. Recent investigations have focused on the impact of human-dog co-sleeping on human sleep but have largely ignored the contextual nature of the practice, including with whom, why, and how people share their beds and bedrooms with their dogs. We explored the nature of human-dog co-sleeping among a large population of Australian dog owners (
n =
1136). Nearly half (49%) of participants reported sleeping with their dog in their bed, 20% indicated their dog slept in their bedroom but not in their bed, and 31% reported their dog slept outside their bedroom. The likelihood of bedsharing with one’s dog increased with participant age and bed size and was higher for individuals with small dogs than those with larger dogs. In addition, bedsharing with one’s dog was more common among individuals who did not have a human bed partner. For each unit increase in the MDORS Dog-Owner Interaction scale, the odds of sleeping with one’s dog increased by 1.39, and for each unit increase in the MDORS Emotional Closeness sub-scale, the odds increased by 1.08. For each unit increase in the MCPQ-R Motivation sub-scale, the odds of sleeping with one’s dog increased by 1.21.We found no association between whether the dog slept on the bed and self-reported sleep quality. However, participants whose dog slept somewhere other than their owner’s bed were 1.45 times more likely to report frequently waking up tired. Bedsharing appears unlikely to impact sleep quality negatively in any meaningful way. In fact, in many cases, dog(s) in the bed may facilitate a more restful night’s sleep than when they sleep elsewhere.
Advancing the Science and Practice of Equine-assisted Services through Community-Academic Partnerships
Authors: Fields Beth , Peters B. Caitlin , Merritt Tamara , Meyers Shannon
Published: October 2022

Ambiguity of the incorporation of animals in services that promote health and well-being is often due to inadequate sample sizes and imprecise outcome measures necessary to detect differences in research groups. Researchers are recognizing that to transcend these concerns and truly affect population health, they must partner with communities. This paper describes guiding principles of community-academic partnerships using two different types of equine-assisted services as illustrations. These principles and illustrative examples demonstrate how researchers and communities can work together to advance science and practice.
Psychotherapy Incorporating Horses to Address Anxiety in Women College Students: A Pilot Study
Authors: Berg Erika L. , Bach-Gorman Amber R. , Hammer Carolyn J.
Published: October 2022

An annual 2019 survey of directors of college counseling centers reported that 60.7% of students seeking counseling present with the predominant concern of anxiety. Furthermore, counseling centers across the United States have seen a rise in the number of students requesting services in recent years, frequently resulting in wait lists for students to receive counseling. Group psychotherapy sessions may mitigate wait times; however due to student anxiety and negative stigma surrounding mental health treatment it can often be challenging to attract students to participate in groups compared to individual sessions. This pilot study aimed to investigate the efficacy of group psychotherapy incorporating equines for undergraduate women college students presenting with concerns of anxiety. Implementing the Equine Assisted Growth and Learning Association’s model of psychotherapy, six women participants attended one 90-minute group session per week for 7 weeks on the campus of North Dakota State University. Students completed the Self Compassion Scale (SCS) and the Depression Anxiety Stress Scales (DASS) at weeks 0 and 7 as pre and post measures of the intervention. A significant increase was observed in the common humanity subscale of the SCS; however, no other differences were found in the remaining SCS subscales nor in the DASS subscales. Anecdotally, multiple students expressed that they would not have persisted in coming to group without the horses present. Furthermore, there was markedly improved attendance rates in the psychotherapy incorporating equine group compared to other group therapies at the counseling center. We recommend that future research examine whether psychotherapy integrating both horses and the tenets of self-compassion can help woman college students improve their anxiety management skills and become more resilient.
Comparing the Effect of Human-Dog Interactions and Progressive Muscle Relaxation on Self-Report and Physiological Measures of Stress
Authors: Beasley Nicole L. , Elvers Greg C , Reeb Roger N. , Torok Hannah L.
Published: October 2022

This study compares the effects of human-dog interactions and progressive muscle relaxation on stress in college students during the week of their final exams using self-report and physiological measures of stress. Students often cope with stress during the final exams period using various strategies such as spending time with a therapy dog. While students often report that their stress is reduced after visiting with a therapy dog, some studies find physiological evidence for a reduction in stress while others do not. During the first day of finals week, students (
N
= 53) in an introductory psychology or a research methods course were randomly assigned to spend 15 minutes with a therapy dog or to spend 15 minutes doing a progressive muscle relaxation task. Heart rate variability, a physiological measure of stress, and two self-report measures of stress (the PSS-10 which is a 10 item questionnaire on the participants’ stress level and the SVAS on which the participants mark a visual scale to indicate their current stress level) were measured both before and after the treatments. Compared to the pre-treatment measures, stress was lower after the treatment. Spending time with a therapy dog can reduce stress associated with final exams. However, the intercorrelations between heart rate variability and the self-report measures were not statistically significant suggesting that the measures might correspond to different dimensions of the stress response, as explained in some theories of stress response and emotion. Future research regarding the effects of therapy dogs on stress should include at least one physiological measure of stress and ideally multiple measures. This inclusion might help clarify the underlying psychological and physiological mechanisms leading to stress reduction.
Community Awareness of Assistance Dog Public Access Rights among Australian Adults
Authors: Howell Tiffani J. , Bennett Pauleen C.
Published: October 2022

Assistance dogs fill a wide variety of disability assistance roles. In many jurisdictions, assistance dogs have the legal right to enter public places with their handlers, including those that are typically off-limits to pet animals. Unfortunately, unlawful denial of access to these places is common, which may be due to lack of understanding about these access rights. The aim of this exploratory study was to determine awareness of assistance dog public access rights among the general population of Australian adults. An online survey was completed by 328 Australian residents, only six of whom had ever lived with an assistance dog. Analyses were primarily descriptive. About half (51%) worked in an environment in which occasional encounters with an assistance dog and handler team would be possible, but most participants reported rarely or never encountering an assistance dog in their community or workplace. Nonetheless, awareness of assistance dog public access rights was generally high, with nearly all participants aware that ‘pet dog’ is not a synonym for assistance dog, and that assistance dogs have the legal right to access shopping centres and public transport. Awareness was lower for limitations on these access rights, such as gatekeepers’ (i.e., people who determine whether a person enters their premises) right to ask for evidence that the dog is an assistance dog, and the right to deny access to a dog that is not well-controlled. Women had significantly higher knowledge about this topic than men, and age was positively correlated with knowledge, but both had weak effect sizes. Future educational campaigns should aim to increase awareness of assistance dogs’ legal rights and obligations, to reduce the likelihood of unlawful access denials in the future.
Sustained Effects of Animal-Assisted Crisis Response on Stress in School Shooting Survivors
Authors: Robino Ariann E. , Feldman David M. , Stein Alyssa N. , Schmaltz Melody A. , Fitzpatrick Hailey A. , Tartar Jaime L. , Pizzo Frankie , Friedman Marah , Feldman Olivia
Published: October 2022

Animal-assisted crisis response (AACR) is an intervention that harnesses the human-animal bond for therapeutic benefit through specially trained animal-handler teams deployed to provide comfort following a mass traumatic event. During the months and years following the shooting at Marjory Stoneman Douglas High School on February 14, 2018, therapy animals joined the campus community to promote healing and stress reduction. The purpose of this quantitative study was to examine the sustained effects on bonding and stress in a sample of survivors of the tragedy who participated in animal-assisted crisis response. Data was collected through a quasi-experimental study of three intervention groups (i.e., discussion of AACR, viewing photos related to AACR, and engaging with therapy animals). Cortisol analysis indicated a reduction in stress post-intervention across groups with the largest difference in the therapy animal interaction group. Implications for AACR and addressing the psychological effects of mass traumas are provided.
Nuclear tension controls mitotic entry by regulating cyclin B1 nuclear translocation
Authors: Dantas Margarida , Oliveira Andreia , Aguiar Paulo , Maiato Helder , Ferreira Jorge G.
Published: October 2022

As cells prepare to divide, they must ensure that enough space is available to assemble the mitotic machinery without perturbing tissue homeostasis. To do so, cells undergo a series of biochemical reactions regulated by cyclin B1-CDK1 that trigger cytoskeletal reorganization and ensure the coordination of cytoplasmic and nuclear events. Along with the biochemical events that control mitotic entry, mechanical forces have recently emerged as important players in cell-cycle regulation. However, the exact link between mechanical forces and the biochemical pathways that control mitotic progression remains unknown. Here, we identify a tension-dependent signal on the nucleus that sets the time for nuclear envelope permeabilization (NEP) and mitotic entry. This signal relies on actomyosin contractility, which unfolds the nucleus during the G2-M transition, activating the stretch-sensitive cPLA2 on the nuclear envelope and regulating the nuclear translocation of cyclin B1. Our data demonstrate how nuclear tension during the G2-M transition contributes to timely and efficient mitotic spindle assembly and prevents chromosomal instability.
Constitutive assembly of Ca2+ entry units in soleus muscle from calsequestrin knockout mice
Authors: Michelucci Antonio , Pietrangelo Laura , Rastelli Giorgia , Protasi Feliciano , Dirksen Robert T. , Boncompagni Simona
Published: October 2022

Calcium (Ca2+) entry units (CEUs) are junctions within the I band of the sarcomere between stacks of sarcoplasmic reticulum (SR) cisternae and extensions of the transverse (T)-tubule. CEUs contain STIM1 and Orai1 proteins, the molecular machinery of store-operated Ca2+ entry (SOCE). In extensor digitorum longus (EDL) fibers of wild-type (WT) mice, CEUs transiently assemble during acute exercise and disassemble several hours thereafter. By contrast, calsequestrin-1 (CASQ1) ablation induces a compensatory constitutive assembly of CEUs in EDL fibers, resulting in enhanced constitutive and maximum SOCE that counteracts SR Ca2+ depletion during repetitive activity. However, whether CEUs form in slow-twitch fibers, which express both the skeletal CASQ1 and the cardiac CASQ2 isoforms, is unknown. Herein, we compared the structure and function of soleus muscles from WT and knockout mice that lack either CASQ1 (CASQ1-null) or both CASQs (dCASQ-null). Ultrastructural analyses showed that SR/T-tubule junctions at the I band, virtually identical to CEUs in EDL muscle, were present and more frequent in CASQ1-null than WT mice, with dCASQ-null exhibiting the highest incidence. The greater incidence of CEUs in soleus from dCASQ-null mice correlated with increased specific force production during repetitive, high-frequency stimulation, which depended on Ca2+ entry. Consistent with this, Orai1 expression was significantly increased in soleus of CASQ1-null mice, but even more in dCASQ-null mice, compared with WT. Together, these results strengthen the concept that CEU assembly strongly depends on CASQ expression and provides an alternative source of Ca2+ needed to refill SR Ca2+ stores to maintain specific force production during sustained muscle activity.
Lattice Thermal Conductivity of MgSiO3 Perovskite and Post-Perovskite under Lower Mantle Conditions Calculated by Deep Potential Molecular Dynamics
Authors: Yang Fenghu , Zeng Qiyu , Chen Bo , Kang Dongdong , Zhang Shen , Wu Jianhua , Yu Xiaoxiang , Dai Jiayu
Published: October 2022

Lattice thermal conductivity (κ
lat) of MgSiO3 perovskite and post-perovskite is an important parameter for the thermal dynamics in the Earth. Here, we develop a deep potential of density functional theory quality under entire thermodynamic conditions in the lower mantle, and calculate the κ
lat by the Green–Kubo relation. Deep potential molecular dynamics captures full-order anharmonicity and considers ill-defined phonons in low-κ
lat materials ignored in the phonon gas model. The κ
lat shows negative temperature dependence and positive linear pressure dependence. Interestingly, the κ
lat undergos an increase at the phase boundary from perovskite to post-perovskite. We demonstrate that, along the geotherm, the κ
lat increases by 18.2% at the phase boundary. Our results would be helpful for evaluating Earth’s thermal dynamics and improving the Earth model.
On the uniqueness of solutions for the basis pursuit in the continuum
Authors: Debarre Thomas , Denoyelle Quentin , Fageot Julien
Published: October 2022

This paper studies the continuous-domain inverse problem of recovering Radon measures on the one-dimensional torus from low-frequency Fourier coefficients, whereKcis the cutoff frequency. Our approach consists in minimizing the total-variation norm among all Radon measures that are consistent with the observations. We call this problem the basis pursuit in the continuum (BPC). We characterize the solution set of (BPC) in terms of uniqueness and describe its sparse solutions which are sums of few signed Dirac masses. The characterization is determined by the spectrum of a Toeplitz and Hermitian-symmetric matrix that solely depends on the observations. More precisely, we prove that (BPC) has a unique solution if and only if this matrix is neither positive definite nor negative definite. If it has both a positive and negative eigenvalue, then the unique solution is the sum of at most 2KcDirac masses, with at least one positive and one negative weight. If this matrix is positive (respectively negative) semi-definite and rank deficient, then the unique solution is composed of a number of Dirac masses equal to the rank of the matrix, all of which have nonnegative (respectively nonpositive) weights. Finally, in cases where (BPC) has multiple solutions, we demonstrate that there are infinitely many solutions composed ofKc+ 1 Dirac masses, with nonnegative (respectively nonpositive) weights if the matrix is positive (respectively negative) definite.
Least-squares method for recovering multiple medium parameters
Authors: Ito Kazufumi , Liang Ying , Zou Jun
Published: October 2022

We present a two-stage least-squares method for inverse medium problems of reconstructing multiple unknown coefficients simultaneously from noisy data. A direct sampling method is applied to detect the location of the inhomogeneity in the first stage, while a total least-squares method with a mixed regularization is used to recover the medium profile in the second stage. The total least-squares method is designed to minimize the residual of the model equation and the data fitting, along with an appropriate regularization, in an attempt to significantly improve the accuracy of the approximation obtained from the first stage. We shall also present an analysis on the well-posedness and convergence of this algorithm. Numerical experiments are carried out to verify the accuracies and robustness of this novel two-stage least-squares algorithm, with high tolerance of noise in the data.
Description of non-covalent interactions in benzyl chalcocyanate crystals from smoothed Cromer–Mann electron density distribution functions
Authors: Leherte Laurence , Bodart Laurie , Wouters Johan , Vercauteren Daniel P
Published: October 2022

A well-known method to characterize non-covalent interactions consists in the topological analysis of electron density distribution (EDD) functions, complemented by the search for minima in the reduced density gradient (RDG) distributions. Here, we characterize intermolecular interactions occurring in crystals of benzyl chalcocyanate compounds through bond critical points (BCP) of the promolecular electron density (ED) built from the crystallographic Cromer–Mann parameters, at several smoothing levels t. The trajectories formed by the t-dependent BCP locations are interpreted in terms of the intermolecular interactions occurring within the crystal arrangements. Chalcogen…nitro BCPs are clearly present in the unsmoothed EDDs but are annihilated as t increases, while chalcogen…chalcogen BCPs appear and are among the only BCPs left at the highest smoothing level. The chalcogen bonds are differentiated from the other chalcogen interactions through the linear chalcogen…BCP…nitro geometry at low smoothing level and their more negative Laplacian values. The annihilation of CPs can be followed by the apparition of a RDG minimum, associated with a very weak interaction. Along the BCP trajectories, the Laplacian shows a progressive concentration of the ED in the intermolecular space within the crystals and adopts the most negative values at the shortest atom…atom separations. At the termination point of a BCP trajectory, the drastic increase of the ellipticity value illustrates the flattening of the EDD.
Topological magnons in one-dimensional ferromagnetic Su–Schrieffer–Heeger model with anisotropic interaction
Authors: Wei Peng-Tao , Ni Jin-Yu , Zheng Xia-Ming , Liu Da-Yong , Zou Liang-Jian
Published: October 2022

Topological magnons in a one-dimensional (1D) ferromagnetic Su–Schrieffer–Heeger (SSH) model with anisotropic exchange interactions are investigated. Apart from the intercellular isotropic Heisenberg interaction, the intercellular anisotropic exchange interactions, i.e. Dzyaloshinskii–Moriya interaction and pseudo-dipolar interaction, also can induce the emergence of the non-trivial phase with two degenerate in-gap edge states separately localized at the two ends of the 1D chain, while the intracellular interactions instead unfavors the topological phase. The interplay among them has synergistic effects on the topological phase transition, very different from that in the two-dimensional (2D) ferromagnet. These results demonstrate that the 1D magnons possess rich topological phase diagrams distinctly different from the electronic version of the SSH model and even the 2D magnons. Due to the low dimensional structural characteristics of this 1D topological magnonic system, the magnonic crystals can be constructed from bottom to top, which has important potential applications in the design of novel magnonic devices.
Temperature-dependent current transport in quasi-vertical Pt/AlN/Al0.6Ga0.4N heterostructure Schottky barrier diodes with significant improved forward characteristic
Authors: Ran Junxue , Chen Renfeng , He Rui , Ji Xiaoli , Yang Jiankun , Wang Junxi , Li Jinmin , Wei Tongbo
Published: October 2022

In this letter, quasi-vertical Schottky barrier diodes (SBDs) based on AlN/Al0.6Ga0.4N heterostructure are fabricated and temperature-dependent current transport is systematically investigated. Benefited from the AlN/Al0.6Ga0.4N heterostructure with high net doping concentration of ∼1 × 1018 cm−3 in Al0.6Ga0.4N, the device demonstrates lower ideality factor of 2.95, high on/off current ratio of ∼108, the on-current of above 40 A cm−2 which is two order magnitude higher than that of the state-of-the-art AlN SBDs. The barrier inhomogeneity is characterized by the model of Gaussian distribution, and the reverse current observed is identified to be traps-related leakage process such as Poole–Frenkel emission and trap assisted tunneling. This work reveals the heterostructure engineering is an alternative pathway to overcome the difficulty of AlN-based SBDs.
The design of a four-wing chaotic system and the application of synchronous control in weak signal detection
Authors: Bai Yulong , Li Xiaofeng , Pan Weishuang
Published: October 2022

Simple fourth-order autonomous differential equations can exhibit chaotic properties. In this paper, a chaotic system with a four-wing attractor is proposed where the varying number of attractor wings depends not only on the system parameters but also on the initial state of the system. First, the phase diagram, Lyapunov exponential (LE) spectrum, bifurcation diagram, Poincaré section diagram and 0–1 test diagram can verify that the system has more complex dynamic characteristics. Meanwhile, not only is the randomness of the system is verified by complexity analysis, but the multistability of the system, namely, the coexistence attractor, is also simulated. Second, using Multisim to build an analog circuit diagram, the circuit simulation results and numerical simulation results coincide, proving the circuit feasibility of the system. Finally, a suitable controller is designed based on Lyapunov stability theory to realize the synchronization of the drive-response system. On the basis of synchronization, disturbance (measured signal) is added to the response system to transform the signal detection into the synchronization error analysis of the drive-response synchronization system. The frequency of synchronization error is obtained by frequency domain analysis, and the frequency value estimated by the multiple signal classification (MUSIC) algorithm. It is found that the proposed chaotic system has more complex dynamics. The method of synchronization control error combined with spectrum estimation can effectively estimate the frequency of weak signal and provide a large detection threshold for weak signal detection.
Four-dimensional Hindmarsh–Rose neuron model with hidden firing multistability based on two memristors
Authors: Yan Shaohui , Zhang Yuyan , Ren Yu , Sun Xi , Wang Ertong , Song Zhenlong
Published: October 2022

Since memristors can be used to describe electromagnetic induction effects, this paper proposes a novel 4D HindMarsh-Rose (HR) neuron model based on two flux-controlled memristors to show complex dynamics of neuronal electrical activity. It has no equilibrium point, revealing hidden dynamical behaviors. The complex dynamics of the system are illustrated by phase portraits, the time sequences, bifurcation diagrams, and Lyapunov exponents spectra. The presented 4D HR neuron model can produce coexisting multiple hidden firing patterns, for instance, periodic spiking, chaotic spiking, transient chaotic spiking, periodic bursting, chaotic bursting, transient chaotic bursting, stochastic bursting, and transient stochastic bursting. Besides, rich nonlinear dynamics, such as anti-monotonicity and initial offset boosting, are also found. Finally, Multisim circuit simulation is performed and the results are in accordance with numerical simulation.
Power spectrum of domain-wall network, and its implications for isotropic and anisotropic cosmic birefringence
Authors: Kitajima Naoya , Kozai Fumiaki , Takahashi Fuminobu , Yin Wen
Published: October 2022

Recently, based on a novel analysis of the Planck satellite data, a hint of a uniform rotation of the polarization of cosmic microwave background photons, called isotropic cosmic birefringence, has been reported.
The suggested rotation angle of polarization of about 0.2–0.4 degrees is close to the fine-structure constant, α ≃ 1/137 rad ≃ 0.42 deg. Interestingly, this coincidence can be naturally explained over a very wide parameter range by the domain walls of axion-like particles. Furthermore, the axion-like particle domain walls predict not only isotropic cosmic birefringence but also anisotropic one that reflects the spatial distribution of the axion-like particle field on the last scattering surface.
In this paper, we perform lattice simulations of the formation and evolution of domain walls in the expanding universe and obtain for the first time the two-point correlation function and power spectrum of the scalar field that constitutes the domain walls.
We find that for initial fluctuations at subhorizon scales, the power spectrum is roughly consistent with analytical predictions based on random wall distributions. However, there is some excess at scales corresponding to the Hubble radius.
Applying our results to the anisotropic cosmic birefringence, we predict the power spectrum of the rotation angles induced by the axion-like particle domain walls for the similar initial condition, and show that it is within reach of future observations of the cosmic microwave background.
A Theoretical Study on the Form Factors of Pentaquark States
Authors: Pal Shukla , Ghosh Rismita , Chakrabarti Ballari , Bhattacharya Aparajita
Published: October 2022

The form factors of the exotic pentaquarks such as

P
c
+

(
4450
)
,
 

P
c
+

(
4380
)
,
 

N
c
0

,
 

Θ
c
0

,
 

Ξ
c
0

etc. have been investigated for the momentum transfers, Q
2 in the range of 0.01 < Q
2 < 1.0 GeV2. The wave function from the statistical model has been used to compute the form factors. The form factors are found to decrease sharply with the increase of Q
2 in the range of 0.01 < Q
2 < 0.1 GeV2 which indicates the scaling violation with the gluon contribution to the form factor and the structure function whereas the form factors show gradual decrease with a small scaling violation in the range of 0.1 < Q
2 < 1.0 GeV2. The results have been compared with the other available theoretical and experimental data.
Determination of growth exponent for percolating clusters of various lattices
Authors: Prasadh P S Devi , Arulgnanam A , Sarkar B K , Saravanakumar B
Published: October 2022

A computer simulation experiment has been carried out near the critical region of percolation clusters of various lattices. This certain growth exponent/spreading velocity exponent has been determined by put on the scaling theory on this percolating cluster near the critical region (i.e., P = Pc
). This exponent is named in a different way in not the same context. Owing to this enormous usage of this exponent to the real physical system, we focus our attention to find this exponent. The value of this exponent is determined for the normal conducting lattices like square, triangular & honey comb and superconducting Ortho I phase & Ortho II phase for different lattice dimensions. From the experiment it is detected that, if the concentration of the site occupancy increases, the spreading velocity or the value of growth exponent is also increases naturally. All the values are found to be less than one, indicating large spreading nature or growth nature physically as per the scaling laws. From our experiments it is found to be the exponent values fall between 0.2 and 0.5 for all lattice dimensions irrespective of lattice type.
An Account on Functional Polymer Composite for Multivariant Application: A Mechanistic Approach
Authors: Das Anamika , Ray Alolika , Mukhopadhyay Jayanta , Mukherjee Moumita , Biswas Satarupa , Mukhopadhyay Madhumita
Published: October 2022

The presented article reports a detailed review of the polymer composite and its applications in multifaceted areas. The novelty of the report is in establishing the mechanistic overview on the functionalization of polymer for selective applications. The most important and established application of polymer is in sensing, polymer electrolyte, biomedical application, point of care application etc. The utilization of functional polymer in fluorescence thermometers is dependent on the maintenance of their lower critical solubility temperature. Polyelectrolytes like conducting polymers are widely applied for chemo sensing applications. The primary mechanism for the functionality of these conducting polymers is the presence of altering single and double bonds which enables the thorough flow of charge within the matrix system. Furthermore, the macromolecular synthetic polymer is subjected to functionalization through composite upon combing with specific salts and filler components. The addition of unreactive/reactive filler components in minute amounts is reported to significantly reduce the polarization loss and increase the cyclability of the matrix when applied to solid-state devices like sensors, fuel cells for stationary and mobile applications, etc. Fuels cells being an example of renewable energy is reported to attract the modern market with emphasis on polymer membrane-based system wherein sulphonic acid-based electrolyte membrane act as the ionic electrolyte conductor. The mechanism of ion conduction within the polymer matrix plays an important role in the application in solid-state devices like sensors, fuel cells, batteries, etc. The review briefly explains the role of ionic conduction as explained using two primary mechanisms like Arrhenius and Vogel Tammann Fulcher. Finally, the role of polymer bio composites is discussed in light of biomedical applications.
Onset of the bound states in strange Λ, Ξ-hypernuclei and hyperspherical three-body model calculation for the corresponding double hyperon hypernuclei
Authors: Alam M , Mondal S H , Hasan M , Khan Md. A
Published: October 2022

In this work, we have explored ground state properties of

10

Λ
Λ

Be hypernucleus in the light of recent observation of the experiment J-PARC E07 and the onset of stability for

10

Λ
Ξ

Be hypernucleus in the three-body framework using Hyperspherical Harmonics Expansion (HHE) method. An effective core-Y (Y= Λ, Ξ) Woods-Saxon potential with adjustable depth parameter is used to reproduce the observed ground state energy of the two-body subsystem by solving the two-body Schrödinger equation. The core-Y potential so obtained is clubbed with the YY potential model of the Nijmegen group to obtain the observables of the double-hyperon hypernuclei. Computed YY separation energy and YY bond energy are compared with the data available in the literature.
Spectral properties of Ni(II) complex of a tridentate pyridine-amide ligand with appended ether functionality [n-(2-Methoxyphenyl)picolinamide]: Theoretical and Experimental studies
Authors: Sonam  , Das D , Das P P
Published: October 2022

Carboxamide groups due to its biological abundance and significance in the primary structure of proteins/metalloenzymes, has been long investigated as donor functionality in synthetic inorganic coordination chemistry. Spectral studies and their theoretical encounters are gaining enormous importance. Electronic detail structure, along with TD-DFT and FT-IR vibrational frequencies of, [Ni(II)L2], HL = N-(2-methoxyphenyl)picolinamide were studied by DFT calculations and are compared with their experimental counterparts. Nice agreement of these two was obtained. Ni(II) utilizes all possible donor sites of the both the ligands and forms hexadentate complex. Orbitals involved in TD-DFT calculated electronic transitions are highlighted, along with magnetic orbitals and spin-density plots. TD-DFT results and comparison of experimental and calculated vibrational wave numbers are listed in tabular fashion. Optimized geometry reveals possible distortions in the structure. All relevant bond angles and bond lengths have been shown. All calculations were done at B3LYP utilizing TZVP and SVP basis sets.
Study of resonances in exotic neutron-rich 14Be by the use of isospectral potential
Authors: Hasan M , Alam M , Mondal S H , Khan Md A
Published: October 2022

In this work, Hyperspherical Harmonic Expansion (HHE) formalism aided by supersymmetric quantum mechanics is used to study bound and resonant states of 14Be in the three-body (12Be+ n + n) cluster model, and the analysis of the resonant states close to the binding threshold utilizes supersymmetric quantum mechanics (SSQM). GPT nucleon-nucleon potential together with SBB core-nucleon potential is chosen for the solution of three-body Schrödinger equation to get the lowest bound state energy and wave function. In the next stage, energy and wave function of the bound state is used to derive an isospectral potential that exhibit deep well following a strong barrier facilitating confinement (or trapping) of particle inside it at some positive energy (E>0). The trapping probability when plotted against energy shows a prominent peak at the energy of resonance. WKB approximation is used to determine the width of resonance width. Calculated resonance energy and width of resonance are compared with those measured experimentally for the promising neutron halo candidate, the 14Be.
Quality assessment of image deburring algorithms
Authors: Garvanova Magdalena , Ivanov Vladimir
Published: October 2022

Camera shake during video recording is a major source of image defocus. Restoring these defocuses is one of the most important tasks in image processing. This article examines and evaluates the most commonly used algorithms in practice, namely: Richardson-Lucy algorithm, Tikhonov regularization, and Blind deconvolution. The comparisons were made using structural similarity, image sharpness, and root mean square error.
Study on the gasification process of the biomass obtained from agricultural waste with the purpose of estimating the energy potential in the Santander region and its surroundings.
Authors: Durán-Sarmiento M A , Del Portillo-Valdés L A , Rueda-Ordonez Y J , Florez-Rivera J S , Rincón-Quintero A D
Published: October 2022

The generation of energy through renewable sources motivates to study the process of gasification of agricultural residual biomass and to obtain the greatest benefit. In turn, the energy potential in the department of Santander was estimated, which represents 2% of the total production nationwide, and an average of the energy production that can be obtained with the gasification process was obtained, yielding a result of 67% efficiency, with this the department of Santander is located in the ranking of bioenergy producing departments in Colombia. As an additional factor, an economic analysis was carried out to calculate an average of how much money can be saved by replacing fossil fuels with biofuels. The gasification of residual biomass is one of the most striking and studied methods today, with which you can contribute positively to the environment and with which you can achieve a bioeconomy quite sustainable and independent of fossil fuels.
Analysis of the corrosion and wear of WC-10Co-4Cr + GNPs coating applied to HSLA DH-36 steel using HVOF
Authors: Kumar Vijay , Verma Rajeev , Kumar Rakesh
Published: October 2022

High strength low alloy (HSLA) steels offer unique properties and features that show their utility in harsh conditions. Wear and corrosion are concerns when using HSLA steel in shipbuilding and marine environment. In such harsh conditions, WC-10Co-4Cr is a suitable candidate for applying a protective coating to HSLA steel using High Velocity Oxy-Fuel (HVOF) to improve wear and corrosion resistance. The addition of graphene nano-platelets (GNPs) to WC-10Co-4Cr powder increased its mechanical qualities due to its unique properties such as low wear and excellent corrosion resistance. In this work, WC-10Co-4Cr + 3% GNP was coated on laser-treated DH-36 steel. The corrosion potential for these coatings on pre-laser textured with pitch-to-diameter ratio 1.67 was −0.437V compared to the pristine DH-36 was −0.821V; while corrosion current density was 0.143 × 10−3 & 5.362 × 10−6, respectively. Finally, the dry sliding wear test using the Pin-on-Disc (PoD) method, microhardness using the Vickers Indentor, and corrosion resistance using a potentiometer were utilised to analyse the coated surface. The wear resistance of steel coated with WC-10Co-4Cr + 3% GNPs was about 1.5 times compared to pristine substrate. Microstructure and morphology of corroded surfaces were examined using FE-SEM. The results reveal that GNPs act as a solid lubricant, improving the surface’s wear resistance.
An analytic model to calculate voxel s-values for 177Lu
Authors: Pistone Daniele , Auditore Lucrezia , Italiano Antonio , Baldari Sergio , Amato Ernesto
Published: October 2022

Objective. 177Lu is one of the most employed isotopes in targeted radionuclide therapies and theranostics, and 3D internal dosimetry for such procedures has great importance. Voxel S-Values (VSVs) approach is widely used for this purpose, but VSVs are available for a limited number of voxel dimensions. The aim of this work is to develop an analytic model for the calculation of 177Lu-VSVs in any cubic voxelized geometry of practical interest. Approach. Monte Carlo (MC) simulations were implemented with the toolkit GAMOS to evaluate VSVs in voxelized geometries of soft tissue from a source of 177Lu homogeneously distributed in the central voxel. Nine geometric setups, containing 15 × 15 × 15 cubic voxels of sides l ranging from 2 mm to 6 mm, in steps of 0.5 mm, were considered. For each l, the VSVs computed as a function of the ‘normalized radius’, R

n
= R/l (with R = distance from the center of the source voxel), were fitted with a parametric function. The dependencies of the parameters as a function of l were then fitted with appropriate functions, in order to implement the model for deducing 177Lu-VSVs for any l within the aforementioned range. Main results. The MC-derived VSVs were satisfactorily compared with literature data for validation, and the VSVs computed with the analytic model agree with the MC ones within 2% for R

n
≤ 2 and within 6% for R

n
> 2. Significance. The proposed model enables the easy and fast calculation, with a simple spreadsheet, of 177Lu-VSVs in any cubic voxelized geometry of practical interest, avoiding the necessity of implementing ad-hoc MC simulations to estimate VSVs for specific voxel dimensions not available in literature data.
Simple and complex spiking neurons: perspectives and analysis in a simple STDP scenario
Authors: Manna Davide L , Vicente-Sola Alex , Kirkland Paul , Bihl Trevor J , Di Caterina Gaetano
Published: October 2022

Spiking neural networks (SNNs) are largely inspired by biology and neuroscience and leverage ideas and theories to create fast and efficient learning systems. Spiking neuron models are adopted as core processing units in neuromorphic systems because they enable event-based processing. Among many neuron models, the integrate-and-fire (I&F) models are often adopted, with the simple leaky I&F (LIF) being the most used. The reason for adopting such models is their efficiency and/or biological plausibility. Nevertheless, rigorous justification for adopting LIF over other neuron models for use in artificial learning systems has not yet been studied. This work considers various neuron models in the literature and then selects computational neuron models that are single-variable, efficient, and display different types of complexities. From this selection, we make a comparative study of three simple I&F neuron models, namely the LIF, the quadratic I&F (QIF) and the exponential I&F (EIF), to understand whether the use of more complex models increases the performance of the system and whether the choice of a neuron model can be directed by the task to be completed. Neuron models are tested within an SNN trained with spike-timing dependent plasticity (STDP) on a classification task on the N-MNIST and DVS gestures datasets. Experimental results reveal that more complex neurons manifest the same ability as simpler ones to achieve high levels of accuracy on a simple dataset (N-MNIST), albeit requiring comparably more hyper-parameter tuning. However, when the data possess richer spatio-temporal features, the QIF and EIF neuron models steadily achieve better results. This suggests that accurately selecting the model based on the richness of the feature spectrum of the data could improve the whole system’s performance. Finally, the code implementing the spiking neurons in the SpykeTorch framework is made publicly available.
Dishevelled controls bulk cadherin dynamics and the stability of individual cadherin clusters during convergent extension
Authors: Huebner Robert J. , Wallingford John B.
Published: October 2022

Planar cell polarity is required for coordinated cadherin and actin dynamics. Superresolution imaging reveals the spatiotemporal patterns of cadherin clustering. Cadherin cluster lifespan and size are highly heterogeneous. Planar cell polarity controls cadherin cluster stability and size.