bluuebunny/crossref_metadata_2025 huggingface dataset:
Responsibility experience for your own life through volunteering
Authors: Gudzinskiene Vida , Kurapkaitiene Neringa
Published: January 2022

Phenomenon of the Volunteering reveals itself through dedicated time for volunteering, duration of volunteering commitment, area where volunteering is implemented and through age group of the volunteers. The object of the study is volunteering experience of young adults. Interpretative Phenomenological Analyses is research methodology. According to the phenomenological approach, research itself is not focusing on any foreseen objectives, oriented to the volunteers’ experience. In this article is presented part of the research, giving deeper view on one of the super-ordinates theme, with the aim: to present responsibility for your own life experience of young adults in long term and fulltime volunteering, while volunteered is held in social help area. In the study participated 6 research participants, 3 young men and 3 young women, 20–30 years old. To collect the data of the research were used semi-structured interviews. Conclusions of the study presented in this article shows 1) that through volunteering experience research participants perceived power and duty of own life’s quality. They got awareness about their own life – they can and they must be responsible of own life. 2) This power of responsibility is hidden in themselves and change of own life depends on the decisions made by them while volunteering. Prior experience of responsibility is opening decision possibilities and freedom possibilities in any change of life.
Evaluation of the volleyball coaches’ experience in a 3-dimensions environment
Authors: Lombard Gilles , Dejong Benjamin , Mouton Alexandre , Cloes Marc
Published: January 2022

The new technologies in sport can help to reproduce a real game context. Therefore, we aim to characterize the experience of volleyball coaches immerged in a 3D volleyball game to see if the device could be a credible tool in a coaching training program. Seventeen volleyball coaches were immerged into three sequences of a 3D volleyball game with Oculus Rift headset before completing a perceptions’ questionnaire composed by 33 items concerning users’ experience factors and 3 open-ended questions. The results show positive scores for the immersion (M = 6.49, SD = 2.84), positive emotions (M = 5.24, SD = 2.69), judgment (M = 7.70, SD = 1.82) and flow (M = 5.83, SD = 2.75) even if this last result has to be taken carefully. The answers to the open-ended questions confirm those data. Despite some limitations, the link between the results and some important notions of the behaviour change as the intrinsic motivation, the self-determination theory and the learning outcomes seems to emphasize the benefits of an implementation of the device into a coaching training program. Nevertheless, this use has to be limited to the training of observations of the environment rather than the intervention training because of the lack of control on the environment and interaction allows by the 3D device.
Applications smartphones pour l’analyse de la performance : un laboratoire dans votre poche
Authors: Morin Jean-Benoît
Published: January 2022

La performance sportive est influencée par les capacités musculaires et physiques des athlètes. Les mesures de référence en laboratoire permettent d’évaluer les productions de force, vitesse, puissance dans des mouvements de saut, de sprint et de musculation, ou encore de biomécanique de la foulée de course, qui comptent parmi les déterminants biomécaniques de la performance sportive. Cependant, bien qu’historiquement développées « sur le terrain » notamment par les travaux d’Étienne-Jules Marey, ces techniques n’étaient pas accessibles au plus grand nombre de pratiquants et praticiens. Grâce au développement récent d’appareils photos et caméras haute fréquence (240 images/s) intégrés dans les smartphones et tablettes du fabricant Apple, des applications ont été inventées et validées par comparaison avec des mesures de référence. Elles utilisent des modèles biomécaniques validés par ailleurs pour calculer force, vitesse, puissance mécanique et performance en saut, lors d’une accélération en sprint, estimer la force maximale lors de mouvement de musculation ou des variables biomécaniques de la foulée de course et leur asymétrie. Le ratio coût/précision/simplicité élevé de ces applications a permis de générer des connaissances sur la performance sportive, mais également des avancées dans l’entraînement sportif qui auraient été impossibles sans la levée de ce verrou technologique.
Vokaltraktbeschwerden und Gesundheitserleben von Pflegenden in Senioreneinrichtungen in der Pandemie
Authors: Schuster Maria , Deitmerg Ursula , Gantner Sophia
Published: January 2022

Die SARS-CoV-2-Pandemie bedeutet für Berufstätige im Gesundheitswesen eine besondere Belastung in mehreren Bereichen, u.a. durch das Tragen einer Mund-Nasen-Bedeckung und damit veränderter Kommunikation. In einer prospektiven Studie wurde die Belastung des Vokaltrakts und das psychisch-körperliche Wohlbefinden hier am Beispiel von Tätigen in der Altenpflege mittels Fragebogen erfasst.

Methoden In 2 Altenpflegeeinrichtungen wurden die standardisierten Fragebogen Symptom-Checkliste 90 in der Kurzversion (Mini-SCL) und die Vocal Tract Discomfort Scale (VTDS) in deutscher Übersetzung eingesetzt, kombiniert mit Fragen zu Alter, Komorbidität, Stimme und bereits erfolgter SARS-CoV-2-Infektion.

Ergebnis Bei einer Rückmeldung von 67 von 100 ausgeteilten Fragebogen zeigten sich bei den teilnehmenden Mitarbeitern (56 Frauen und 11 Männer, 45,2 ± 11,5 Jahre alt) erhöhte Werte für beide Fragebogen. Im Mini-SCL wiesen in der Skala Depressivität 23,8% erhöhte Werte auf, in der Skala Ängstlichkeit 49,3%, in der Skala Somatisierung 55,2% und in der Gesamtskala 44,7%. Bei 52% der Teilnehmer ergaben sich erhöhte Werte im VTDS. Zwischen dem VTDS und den Einzelskalen des Mini-SCL sowie zu Stimmbeschwerden bestand jeweils ein signifikanter Zusammenhang.

Diskussion In der Altenpflege Tätige leiden während der Pandemie vermehrt unter psychischen und physischen Beschwerden. Es bestehen Zusammenhänge zwischen Missempfindungen im Vokaltrakt und Stimmsymptomen sowie dem emotionalen und körperlichen Wohlbefinden. Stimmhygienische Schulungen können bei den aktuell erhöhten kommunikativen Anforderungen hilfreich sein.
Impact of Treatment Modalities upon Survival Outcomes in Skull Base and Clival Chordoma: An NCDB Analysis
Authors: Muhonen Ethan G. , Yasaka Tyler M. , Lehrich Brandon M. , Goshtasbi Khodayar , Papagiannopoulos Peter , Tajudeen Bobby A. , St John Maie A. , Harris Jeremy P. , Hsu Frank P.K. , Kuan Edward C.
Published: January 2022

Objectives Skull base chordomas are locally aggressive malignant tumors derived from the notochord remnant. There are limited large-scale studies examining the role and extent of surgery and radiation therapy.

Design Analysis of the National Cancer Database (NCDB) was performed to evaluate the survival outcomes of various treatments, and to assess for predictors of overall survival (OS).

Participants This is a retrospective, population-based cohort study of patients diagnosed with a clival/skull base chordoma between 2004 and 2015 in the NCDB.

Main Outcome Measures The primary outcome was overall survival (OS).

Results In all, 468 cases were identified. Forty-nine percent of patients received surgery and 20.7% had positive margins. Mean age at diagnosis was 48.4 years in the surgical cohort, and 55% were males. Of the surgical cohort, 33.8% had negative margins, 20.7% had positive margins, and 45.5% had unknown margin status. Age ≥ 65 (hazard ratio [HR]: 3.07; 95% confidence interval [CI]: 1.63–5.76; p < 0.001), diagnosis between 2010 and 2015 (HR: 0.49; 95% CI: 0.26–0.90; p = 0.022), tumor size >5 cm (HR: 2.29; 95% CI: 1.26–4.15; p = 0.007), and government insurance (HR: 2.28; 95% CI: 1.24–4.2; p = 0.008) were independent predictors of OS. When comparing surgery with or without adjuvant radiation, no survival differences were found, regardless of margin status (p = 0.66).

Conclusion Surgery remains the mainstay of therapy. Advanced age (>65 years), large tumor size, and government insurance were predictors of worse OS. Whereas negative margins and the use of adjuvant radiation did not appear to impact OS, these may very well reduce local recurrences. A multidisciplinary approach is critical in achieving optimal outcomes in this challenging disease.
UV-Light-Induced Dehydrogenative N-Acylation of Amines with 2-Nitrobenzaldehydes To Give 2-Aminobenzamides
Authors: Deng Wei , Qiu Renhua , Zeng Dishu , Yang Tianbao , Tang Niu , Xiang Jiannan , Yin Shuang-Feng , Kambe Nobuaki
Published: January 2022

A simple, mild, green, and efficient method for the synthesis of 2-aminobenzamides is highly desirable. Herein, we report the development of an efficient, one-pot strategy starting from 2-aminobenzaldehydes and amines with acetic acid in ethyl acetate/acetone using irradiation with UV light for the synthesis of 2-aminobenzamides in high yields; 32 examples proceeded successfully by this photo-induced protocol in up to 92% yield. The reaction was also readily achieved on a gram scale. The utility of the 2-aminobenzamide building block in organic synthesis was shown by their use in the preparation of quinazolinone derivatives. The method was applied to amino acid derivatives as the amine component, which smoothly gave N-(2-aminobenzoyl)acetate derivatives at room temperature. Finally, a plausible mechanism is proposed.
Impact of Design of Experiments in the Optimisation of Catalytic Reactions in Academia
Authors: Carlone Armando , Nori Valeria , Sinibaldi Arianna , Pesciaioli Fabio
Published: January 2022

Design of Experiments (DoE) is extensively and routinely used in industry; however, in recent decades, it has gained increasing interest from academia in organic synthesis. The use of chemometrics is an attractive strategy to find the real optimum in chemical reactions, especially when affected by several variables. DoE has been applied in a growing number of synthetic transformations over the years, where it undoubtedly helps in the process of optimisation, saving costs and time. This review concisely discusses the chemometric basis of Design of Experiments and highlights several examples in which DoE is applied in organic synthesis.

1 Introduction

2 Chemometric Basis of DoE

3 DoE Applied in Catalysis: Selected Examples

3.1 DoE in Metal Catalysis

3.2 DoE in Biocatalysis

3.3 DoE in Organocatalysis

4 Conclusions
Radical Addition of 4-Hydroxyquinazolines and Alkylation of Quinones by the Electro-Induced Homolysis of 4-Alkyl-1,4-di­hydropyridines
Authors: Feng Qiping , Wang Ping , Luo Xiaosheng
Published: January 2022

The formation of C(sp3)-centered radicals via the electro-­induced homolysis of 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) is reported. The resulting alkyl radicals reacted with 4-hydroxyquinazolines or quinones to afford 2-alkyldihydroquinazolinones or alkylated quinones. A broad range of alkyl DHPs could be used as versatile radical precursors under electrolysis conditions. This alterative strategy provided a simple and effective pathway for the construction of C(sp2)–C(sp3) and C(sp3)–C(sp3) bonds under mild conditions.
Antiplaque Efficacy of a Novel Moringa oleifera Dentifrice: A Randomized Clinical Crossover Study
Authors: Duarte Kimberly , Thomas Biju , Varma Sudhir Rama , Kamath Vinayak , Shetty Bhavya , Kuduruthullah Syed , Nambiar Manjusha
Published: January 2022

Objectives The use of herbal dentifrices has grown exponentially over the years. They are categorically referred to as ethnomedicines. Various agents have been tried with contradicting findings based on phytopharmacological analysis. Miswak is one agent which has been used over the years. A novel Moringa oleifera-based dentifrice has shown promising results in terms of its cytotoxicity, biocompatibility, and as a potent anti-inflammatory agent. Therefore, the present study aims to compare the efficacy of two commercially available miswak- and moringa-based herbal dentifrices on the reduction of plaque and gingivitis scores.

Materials and Methods This randomized clinical crossover study included 20 subjects with mild to moderate gingivitis. The study was conducted over a total examination period of 20 days with a wash-out period of 2 weeks between the use of both the toothpastes. The plaque index and gingival index of the study subjects were recorded at the designated time intervals throughout the study period.

Statistical Analysis The data collected were entered on Microsoft Excel, and statistical analysis using SPSS software (SPSS version 28, IBM Corp, Armonk, New York, United States) was done. The statistical test used was the Wilcoxon signed-rank test. Moreover, p ≤0.05 was considered significant.

Results The results showed that the reduction in mean gingival index scores from baseline to day 3 was more statistically significant in the moringa-based dentifrice. Similarly, the plaque index scores showed statistically significant reduction following the use of the moringa-based dentifrice when compared with the miswak dentifrice. This study reveals that the moringa dentifrice is a safe and effective agent in reducing plaque accumulation and treating gingival inflammation.

Conclusion The current study aims to provide an insight into the possible role of moringa dentifrice as a possible adjunctive oral hygiene aid.
Comparison of Occlusal Parameters between Open Bite and Nonopen Bite Patients Using the T-Scan III System: A Pilot Study
Authors: Chaikla Katika , Pumklin Jittima , Piyapattamin Thosapol
Published: January 2022

Objective To evaluate and compare the first tooth contact region, occlusion time, time to generate total force, and force distribution between open bite (OB) and non-OB (NOB) patients at the maximum intercuspation position using the T-Scan III system.

Materials and Methods Sixteen patients were divided into the OB and NOB groups (n = 8 for each group). The T-Scan III system was used to evaluate the first tooth contact region, occlusion time, time to generate total force, and force distribution.

Statistical Analysis The mean patient age, overjet, overbite, occlusion time, and time to generate total force were compared between the groups by independent samples t-test. Relative force distributions between groups and among regions were compared by the Mann–Whitney U- and Kruskal–Wallis H-tests, respectively. A probability value of less than 5% (p < 0.05) was considered significant.

Results Differences in the first tooth contact region between groups were observed. The molar region was the first tooth contact region in the OB group, while first tooth contact was observed in all regions in the NOB group. Neither the occlusion time nor the time to generate total force was significantly different between the groups (p > 0.05). The highest force distributions were observed in the molar regions in both groups. Significant intragroup differences were found among all regions (p < 0.05), except between the anterior and premolar regions in the NOB group (p = 0.317). Intergroup differences in the force distributions in the anterior (p = 0.000), premolar (p = 0.038), and molar (p = 0.007) regions were significant.

Conclusion Unlike in the NOB group, in which first tooth contact occurred in every region, in the OB group, first tooth contact occurred only in the molar region. Compared with those in the NOB group, the force distributions in the OB group were approximately 1.5 times higher in the molar region but were significantly lower in the anterior and premolar regions.
Endovascular Management of Iatrogenic Pseudoaneurysm of Internal Maxillary Artery after Dental Extraction
Authors: Singh Harsh Anand , Kumar Ishan , Singh Pramod Kumar , Varshney Anshul , Verma Ashish
Published: January 2022

Pseudoaneurysm developing from the internal maxillary artery is a rare but potentially fatal condition. We describe a case of iatrogenic pseudoaneurysm of the internal maxillary artery developed during dental extraction and successful endovascular closure of the feeder artery. At 2-month follow-up, the patient remained well with persistent thrombosis of pseudoaneurysm.
Digital Phenotyping in Clinical Neurology
Authors: Gupta Anoopum S.
Published: January 2022

Internet-connected devices, including personal computers, smartphones, smartwatches, and voice assistants, have evolved into powerful multisensor technologies that billions of people interact with daily to connect with friends and colleagues, access and share information, purchase goods, play games, and navigate their environment. Digital phenotyping taps into the data streams captured by these devices to characterize and understand health and disease. The purpose of this article is to summarize opportunities for digital phenotyping in neurology, review studies using everyday technologies to obtain motor and cognitive information, and provide a perspective on how neurologists can embrace and accelerate progress in this emerging field.
Neuroethics in the Era of Teleneurology
Authors: Young Michael J.
Published: January 2022

The accelerating integration of telehealth technologies in neurology practice has transformed traditional interactions between neurologists and patients, allied clinicians and society. Despite the immense promise of these technologies to improve systems of neurological care, the infusion of telehealth technologies into neurology practice introduces a host of unique ethical challenges. Proactive consideration of the ethical dimensions of teleneurology and of the impact of these innovations on the field of neurology more generally can help to ensure responsible development and deployment across stages of implementation. Toward these ends, this article explores key ethical dimensions of teleneurology practice and policy, presents a normative framework for their consideration, and calls attention to underexplored questions ripe for further study at this evolving nexus of teleneurology and neuroethics. To promote successful and ethically resilient development of teleneurology across diverse contexts, clinicians, organizational leaders, and information technology specialists should work closely with neuroethicists with the common goal of identifying and rigorously assessing the trajectories and potential limits of teleneurology systems.
State of the Art: Contrast Enhanced 4D Ultrasound to Monitor or Assess Locoregional Therapies
Authors: Tantawi Mohamed , Shamimi-Noori Susan , Shaw Colette M. , Eisenbrey John R.
Published: January 2022

Locoregional therapies (LRTs) are an essential management tool in the treatment of primary liver cancers or metastatic liver disease. LRTs include curative and palliative modalities. Monitoring treatment response of LRTs is crucial for maximizing benefit and improving clinical outcomes. Clinical use of contrast-enhanced ultrasound (CEUS) was introduced more than two decades ago. Its portability, cost effectiveness, lack of contraindications and safety make it an ideal tool for treatment monitoring in numerous situations. Two-dimensional dynamic CEUS has been proved to be equivalent to the current imaging standard in the guidance of LRTs, assessment of their adequacy, and detection of early tumor recurrence. Recent technical advances in ultrasound transducers and image processing have made 3D CEUS scanning widely available on most commercial ultrasound systems. 3D scanning offers a broad multiplanar view of anatomic structures, overcoming many limitations of two-dimensional scanning. Furthermore, many ultrasound systems provide real-time dynamic 3D CEUS, also known as 4D CEUS. Volumetric CEUS has shown to perform better than 2D CEUS in the assessment and monitoring of some LRTs. CEUS presents a valid alternative to the current imaging standards with reduced cost and decreased risk of complications. Future efforts will be directed toward refining the utility of 4D CEUS through approaches such as multi-parametric quantitative analysis and machine learning algorithms.
Endovascular Rescue for Renal Artery Pseudoaneurysms following Minimally Invasive Robot-Assisted Partial Nephrectomy—A Case Series
Authors: Bonala Nagateja , Bhargavi Vidya , Subbanna Indushekhar , KS Bharath , Patel Rajkumar
Published: January 2022

Nephron sparing surgery or partial nephrectomy has been employed ever since in cases of renal tumors with an aim to preserve the function of residual kidney. Lately, there has been increasing adoption in robot-assisted techniques for partial nephrectomy. However, renal surgeries of any kind have always been a hazard for postoperative vascular complications owing to high vascularity of the renal tissues, of which renal artery pseudoaneurysm is one of the most fatal complications. We present a case series where highly super-selective embolization rescues the patient and augments the nephron sparing nature of the precise robot-assisted partial nephrectomy.
Momentum approach to the 1/r2 potential as a toy model of the Wilsonian renormalization
Authors: Dereziński Jan , Grocholski Oskar
Published: January 2022

The Bessel operator, that is, the Schrödinger operator on the half-line with a potential proportional to 1/x2, is analyzed in the momentum representation. Many features of this analysis are parallel to the approach according to Wilson on quantum field theory: one needs to impose a cutoff, add counterterms, and study the renormalization group flow with its fixed points and limit cycles.
Effects of topological characteristics on rhythmic states of the D-dimensional Kuramoto model in complex networks
Authors: Ling Xiang , Ju Wen-Bin , Guo Ning , Zhu Kong-Jin , Wu Chao-Yun , Hao Qing-Yi
Published: January 2022

Synchronization is a ubiquitous phenomenon in engineering and natural ecosystems. While the dynamics of synchronization modeled by the Kuramoto model are commonly studied in two dimensions and the state of dynamic units is characterized by a scalar angle variable, we studied the Kuramoto model generalized to D dimensions in the framework of a complex network and utilized the local synchronous order parameter between the agent and its neighbors as the controllable variable to adjust the coupling strength. Here, we reported that average connectivity of networks affects the time-dependent, rhythmic, cyclic state. Importantly, we found that the level of heterogeneity of networks governs the rhythmic state in the transition process. The analytical treatment for observed scenarios in a D-dimensional Kuramoto model at D=3 was provided. These results offered a platform for a better understanding of time-dependent swarming and flocking dynamics in nature.
Uniform attractors for reaction–diffusion equations with a larger class of external forces
Authors: Zhu Xiangming , Zhong Chengkui
Published: January 2022

The existence and structure of Lp uniform attractors for reaction–diffusion equations with a larger class of external forces are considered. First, we introduce a new class of external forces g, which is larger than the class of normal functions. Then, by investigating the property of the hull H(g) and with some prior estimates, we obtain the existence and structure of the uniform (L2-Lp) attractors.
Calibration of polyvinylidene fluoride (PVDF) stress gauges under high-impact dynamic compression by machine learning
Authors: Qin Shuang , Yu Zheng , Zhang Xu , Yang Shuqi , Peng Wenyang , Zhao Feng
Published: January 2022

Calibration of stress gauges is of great importance for understanding the behaviors of materials under high dynamic impacts. However, commonly used calibration models have little transferability due to ignoring the influences of the gauge parameters. In this work, we propose a systematic approach that can generate effective and transferable calibration models including multiple independent variables by machine learning. Specifically, we conduct high-impact dynamic compression experiments using polyvinylidene fluoride (PVDF) stress gauges with two different thicknesses and varying remnant polarizations at shock levels from 0.3 to 10 GPa. To best characterize the comprehensive calibration relationship, we select a set of five features (combined by strain, remnant polarization, and film thickness) by feature engineering and use Lasso with the bagging ensemble as an algorithm to train the machine learning model. For comparison, we also propose semiempirical models that calibrate PVDF gauges effectively, but without including thickness and remnant polarization. Our results show that the machine learning model is more precise and more reasonable in physics. The predicted dependences of the calibration curves on remnant polarization and film thickness by the machine learning model are qualitatively consistent with the physics scenario. This work reveals the potential of machine learning methods to improve gauge calibration for better performance and transferability. The method used in this work is applicable to the calibration of any stress gauges with multiple variables.
Physics of the high specific impulse alternative low power hybrid ion engine (alphie): Direct thrust measurements and plasma plume kinetics
Authors: Conde L. , Maldonado P. E. , Damba J. , Gonzalez J. , Domenech-Garret J. L. , Donoso J. M. , Castillo M. A.
Published: January 2022

The Alternative Low Power Ion Engine (alphie) is a high specific impulse plasma thruster different from conventional gridded ion engines (GIEs). It uses only one external cathode and ions and electrons flow through the open spaces of its two grids, whereas only ions are transported through the GIE ion optics. Ionizing electrons from the cathode move inward to the alphie ionization chamber and ions, which are neutralized by electrons from the same cathode, exit along the opposite direction. These currents together with the voltages applied to the grids produce a self-consistent electric field that accelerates the charges. The one-dimensional ion velocity distribution and the electron energy spectra in the collisionless alphie plasma plume are studied along its axial axis of symmetry. The thruster produces a mesothermal plasma flow with a non-monotone plasma potential profile along the axial direction. The ion populations observed are of those accelerated by the self-consistent electric field and a low velocity group that results from the charge exchange collisions in the thruster. Both populations remain essentially unaltered in the plasma flow. Conversely, the two electron groups observed merge along the axial direction of the plume following the changes in the plasma potential. The temperatures of ion populations are high by the neutral gas heating inside the thruster by high-energy ionizing electrons. The direct measurement of thrusts of 0.8–3.5 mN for argon gives 13 900–20 000 s specific impulses. These high values might be explained by the additional contribution to the thrust by the remaining non-ionized hot neutral gas effusion through the apertures of grids.
A phytoplankton–zooplankton–fish model with chaos control: In the presence of fear effect and an additional food
Authors: Sajan  , Sasmal Sourav Kumar , Dubey Balram
Published: January 2022

The interplay of phytoplankton, zooplankton, and fish is one of the most important aspects of the aquatic environment. In this paper, we propose to explore the dynamics of a phytoplankton–zooplankton–fish system, with fear-induced birth rate reduction in the middle predator by the top predator and an additional food source for the top predator fish. Phytoplankton–zooplankton and zooplankton–fish interactions are handled using Holling type IV and II responses, respectively. First, we prove the well-posedness of the system, followed by results related to the existence of possible equilibrium points. Conditions under which a different number of interior equilibria exist are also derived here. We also show this existence numerically by varying the intrinsic growth rate of phytoplankton species, which demonstrates the model’s vibrant nature from a mathematical point of view. Furthermore, we performed the local and global stability analysis around the above equilibrium points, and the transversality conditions for the occurrence of Hopf bifurcations and transcritical bifurcations are established. We observe numerically that for low levels of fear, the system behaves chaotically, and as we increase the fear parameter, the solution approaches a stable equilibrium by the route of period-halving. The chaotic behavior of the system at low levels of fear can also be controlled by increasing the quality of additional food. To corroborate our findings, we constructed several phase portraits, time-series graphs, and one- and two-parametric bifurcation diagrams. The computation of the largest Lyapunov exponent and a sketch of Poincaré maps verify the chaotic character of the proposed system. On varying the parametric values, the system exhibits phenomena like multistability and the enrichment paradox, which are the basic qualities of non-linear models. Thus, the current study can also help ecologists to estimate the parameters to study and obtain such important findings related to non-linear PZF systems. Therefore, from a biological and mathematical perspective, the analysis and the corresponding results of this article appear to be rich and interesting.
Atomistic simulation on the formation mechanism of bonding interface in explosive welding
Authors: Feng Jianrui , Liu Rui , Liu Kaiyuan , Zhou Qiang , Yang Rongjie , Chen Pengwan
Published: January 2022

Explosive welding can join a wide variety of both similar and dissimilar metals. However, because of the extremely fast welding process and micro-sized interfacial morphologies, it is a challenge to experimentally acquire the complete dynamic microscopic information. In this paper, the formation of the bonding interface was modeled through molecular dynamics simulations. Three significant phenomena, including a flat/wavy interface, wave formation, and fine grains, were investigated. The simulation results demonstrate that a flat interface is formed in the solid-state welding while a wavy interface is produced in the liquid-state welding. The wave formation can be explained by the jet that sequentially impacts the flyer plate and the base plate. There are two different pathways to form fine grains. At the regions of the bonding interface and the vortex, the fine grains are generated after the cooling process. Away from the bonding interface, the fine grains are produced by the drastic collision between the jet and the bonding surfaces.
Fano factor in self-similar multibarrier structure based on graphene monolayer
Authors: Miniya M. , Oubram O. , El Hachimi A. G. , Gaggero-Sager L. M.
Published: January 2022

In this paper, we investigated the Fano factor in two types of self-similar potential structures in a graphene monolayer. These structures are substrate-based potential and electrostatic-based potential. However, in order to determine the Fano factor in such structures, we solved the Dirac Hamiltonian by using the transfer matrix method. We found that the self-similar substrate-based potential structure manifests a self-similar behavior in the Fano factor and conductance. Therefore, we proposed scaling rules that represent a scale invariance between generations, main barrier heights, and total lengths of the structures. In particular, the maximum Fano factor value was reported for the self-similar electrostatic-based potentials. More analysis was given in terms of the generation, main barrier heights, and structure’s total lengths. These kinds of structures could be used to control the Fano factor.
A complex network approach to study the extreme precipitation patterns in a river basin
Authors: Agarwal Ankit , Guntu Ravi Kumar , Banerjee Abhirup , Gadhawe Mayuri Ashokrao , Marwan Norbert
Published: January 2022

The quantification of spatial propagation of extreme precipitation events is vital in water resources planning and disaster mitigation. However, quantifying these extreme events has always been challenging as many traditional methods are insufficient to capture the nonlinear interrelationships between extreme event time series. Therefore, it is crucial to develop suitable methods for analyzing the dynamics of extreme events over a river basin with a diverse climate and complicated topography. Over the last decade, complex network analysis emerged as a powerful tool to study the intricate spatiotemporal relationship between many variables in a compact way. In this study, we employ two nonlinear concepts of event synchronization and edit distance to investigate the extreme precipitation pattern in the Ganga river basin. We use the network degree to understand the spatial synchronization pattern of extreme rainfall and identify essential sites in the river basin with respect to potential prediction skills. The study also attempts to quantify the influence of precipitation seasonality and topography on extreme events. The findings of the study reveal that (1) the network degree is decreased in the southwest to northwest direction, (2) the timing of 50th percentile precipitation within a year influences the spatial distribution of degree, (3) the timing is inversely related to elevation, and (4) the lower elevation greatly influences connectivity of the sites. The study highlights that edit distance could be a promising alternative to analyze event-like data by incorporating event time and amplitude and constructing complex networks of climate extremes.
Room temperature plasmonic graphene hot electron bolometric photodetectors: A comparative analysis
Authors: Gosciniak Jacek , Khurgin Jacob B.
Published: January 2022

The performance of a recently proposed integrated graphene-bolometric photodetector is assessed. The responsivity of hundreds of A/W and speed on the scale of hundreds of GHz are predicted. The impressive performance is attributed to the small length over which the energy is absorbed by graphene. The short length leads to a highly enhanced energy density, which causes the increase of the electron temperature in graphene. The model has been validated against recently published experimental results from high-speed graphene photodetectors and found to be in good agreement.
Broadband continuous achromatic and super-dispersive metalens in near-infrared band
Authors: Shan Xin , Li Zile , Li Jiaxin , Fu Rao , Zhou Zhou , He Zhixue , Zheng Guoxing
Published: January 2022

For a long time, dispersion is always an important issue in optics. In recent decades, metasurfaces with the excellent optical field manipulating performance have provided a new solution to realize dispersion management. However, existing strategies usually rely on numerous simulations to select appropriate nanostructures, which are not intuitive and time-consuming. Here, we theoretically analyzed the dispersion controlling mechanism of nanostructured metasurfaces based on the effective refractive index theory. By simultaneously controlling the basic phase and the phase–frequency slope, phase profiles of the dispersion-tailored metalens can be reproduced. Adopting this strategy, continuous achromatic and super-dispersive cylindrical metalenses were designed using a transmissive dielectric metasurface with simple nanostrips. Simulated result shows that, in the near-infrared band from 1200 to 1600 nm, the chromatic dispersion can be reduced to less than a quarter of the regular one for the achromatic metalens, while it has about two times increase for the super-dispersive metalens. In addition, the two different types of metalenses have high efficiency of above 60% and narrow full width at half maximum near the diffraction limit over the 400 nm near-infrared band. These extraordinary properties offer a broad application prospect for the metalens in the field of highly integrated imaging, multispectral detection, tomography, etc.
Bifurcations of mixed-mode oscillations in three-timescale systems: An extended prototypical example
Authors: Kaklamanos P. , Popović N. , Kristiansen K. U.
Published: January 2022

We study a class of multi-parameter three-dimensional systems of ordinary differential equations that exhibit dynamics on three distinct timescales. We apply geometric singular perturbation theory to explore the dependence of the geometry of these systems on their parameters, with a focus on mixed-mode oscillations (MMOs) and their bifurcations. In particular, we uncover a novel geometric mechanism that encodes the transition from MMOs with single epochs of small-amplitude oscillations (SAOs) to those with double-epoch SAOs; the former feature SAOs or pseudo-plateau bursting either “below” or “above” in their time series, while in the latter, SAOs or pseudo-plateau bursting occur both “below” and “above.” We identify a relatively simple prototypical three-timescale system that realizes our mechanism, featuring a one-dimensional S-shaped 2-critical manifold that is embedded into a two-dimensional S-shaped critical manifold in a symmetric fashion. We show that the Koper model from chemical kinetics is merely a particular realization of that prototypical system for a specific choice of parameters; in particular, we explain the robust occurrence of mixed-mode dynamics with double epochs of SAOs therein. Finally, we argue that our geometric mechanism can elucidate the mixed-mode dynamics of more complicated systems with a similar underlying geometry, such as a three-dimensional, three-timescale reduction of the Hodgkin–Huxley equations from mathematical neuroscience.
Numerical simulation of reservoir computing with magnetic nanowire lattices without inversion symmetry
Authors: Hon K. , Takahashi K. , Enju K. , Goto M. , Suzuki Y. , Nomura H.
Published: January 2022

We demonstrate the performance of magnetic nanowire lattices for reservoir computing using micromagnetic simulation. Domain walls are injected into nanowires as the input and are driven by clocking magnetic fields. The static magnetization states of wires are used as the reservoir states. The distribution of node weights shows that the device saves the memory as a shift register, and the domain walls provide the nonlinear computational power for reservoir computing. The maximum short-term memory capacity of 5 and the parity-check capacity of 5 are achieved. We expect the maximum capacities can be boosted by increasing the number of asymmetric structures and the length of the wires.
Comparative study on (Na0.47Bi0.47Ba0.06)0.95A0.05TiO3 (A = Sr2+/Ca2+) lead-free ceramics: Scaling behavior of ferroelectric hysteresis loop
Authors: Liu Li-Na , Chen Xiao-Ming , Jing Rui-Yi , Lu Jiang-Bo , Lian Han-Li , Zhou Jian-Ping , Liu Peng
Published: January 2022

Scaling behavior of dynamic hysteresis of (Na0.47Bi0.47Ba0.06)0.95A0.05TiO3 (A = Sr2+/Ca2+) (expressed as BNBT-Sr and BNBT-Ca, respectively) lead-free ceramics was comparatively studied. BNBT-Ca exhibits typical ferroelectric hysteresis (polarization vs electric field, P–E) loops, while BNBT-Sr shows pinched P–E loops. The two samples' electric field and frequency-dependent dynamic hysteresis behavior were systematically investigated. The dopants difference (Sr2+/Ca2+) produces different scaling behavior of dynamic hysteresis, which is related to the electric field-induced phase transition and domain size between BNBT-Sr and BNBT-Ca.
SERS-based ssDNA composition analysis with inhomogeneous peak broadening and reservoir computing
Authors: Nguyen Phuong H. L. , Rubin Shimon , Sarangi Pulak , Pal Piya , Fainman Yeshaiahu
Published: January 2022

Surface-enhanced Raman spectroscopy employed in conjunction with post-processing machine learning methods is a promising technique for effective data analysis, allowing one to enhance the molecular and chemical composition analysis of information rich DNA molecules. In this work, we report on a room temperature inhomogeneous broadening as a function of the increased adenine concentration and employ this feature to develop one-dimensional and two dimensional chemical composition classification models of 200 long single stranded DNA sequences. Afterwards, we develop a reservoir computing chemical composition classification scheme of the same molecules and demonstrate enhanced performance that does not rely on manual feature identification.
Application of the method of parallel trajectories on modeling the dynamics of COVID-19 third wave
Authors: Contoyiannis Y. , Stavrinides S. G. , Hanias M. P. , Kampitakis M. , Papadopoulos P. , Picos R. , Potirakis S. M. , Kosmidis E.
Published: January 2022

In this paper, we present a new method for successfully simulating the dynamics of COVID-19, experimentally focusing on the third wave. This method, namely, the Method of Parallel Trajectories (MPT), is based on the recently introduced self-organized diffusion model. According to this method, accurate simulation of the dynamics of the COVID-19 infected population evolution is accomplished by considering not the total data for the infected population, but successive segments of it. By changing the initial conditions with which each segment of the simulation is produced, we achieve close and detailed monitoring of the evolution of the pandemic, providing a tool for evaluating the overall situation and the fine-tuning of the restrictive measures. Finally, the application of the proposed MPT on simulating the pandemic's third wave dynamics in Greece and Italy is presented, verifying the method's effectiveness.
Size-driven transition of domain switching kinetics in LiNbO3 domain-wall memory
Authors: Zhang Wen Di , Jiang Jun , Jiang An Quan
Published: January 2022

Repetitive erasure/creation of conducting domain walls between two parallel/antiparallel domains at bipolar write voltages enables the high storage density of a ferroelectric domain-wall memory. Generally, the domain switching kinetics is described by the Kolmogorov–Avrami–Ishibashi model on the basis of domain nucleation and growth without the consideration of distributive defect pinning energies. Here, mesa-like cells were etched from single-crystal LiNbO3 thin films bonded to SiO2/Si wafers, and Pt metal contacts were deposited at their sides. The abrupt off-to-on current jump occurs at a typical domain switching time for the cell in a lateral size above 111 nm, implying the non-Kolmogorov–Avrami–Ishibashi domain switching kinetics immune to the defect pinning effect. However, the domain switching time has a broad distribution for the cell below 49 nm, implying the defect-controlled domain switching mechanism. A new model is developed to describe the size-driven transition. The reliability tests of the memory show a fast operation speed (<2 ns) and excellent reliability of on/off switching states for mass production.
Transition metal halide nanowires: A family of one-dimensional multifunctional building blocks
Authors: Fu Li , Shang Chanjuan , Zhou Si , Guo Yu , Zhao Jijun
Published: January 2022

Low-dimensional materials with definite geometrical and electronic structures have long been pursued to fulfill the requirement of technological devices toward miniaturization, multifunctionality, and precise manufacturing. Inspired by the emerging transition metal halide monolayers with intriguing magnetic behavior, here we systematically explore stable one-dimensional (1D) structures of transition metal halides. By first-principles calculations, a total of 208 TMX2 and TMX3 (TM is 3d, 4d, 5d transition metal elements; X = F, Cl, Br, I) nanowires have been predicted, showing diverse electronic and magnetic properties, such as ferromagnetic semiconductors, half metals, and antiferromagnets. They possess many application-desired characters, including a wide range of bandgaps, small carrier effective masses, outstanding capability for solar energy harvesting, and strong ferromagnetic or antiferromagnetic order. This large family of TMXn nanowires provides a great platform for exploring exotic 1D physics as well as for designing high-performance devices.
Ferrimagnetic compensation and its thickness dependence in TbFeCo alloy thin films
Authors: Ishibashi Mio , Yakushiji Kay , Kawaguchi Masashi , Tsukamoto Arata , Nakatsuji Satoru , Hayashi Masamitsu
Published: January 2022

Rare earth (RE)–transition metal (TM) ferrimagnetic thin films have attracted significant interest for their broad range of functionalities associated with the reduced net magnetization. Here, we study the magnetic properties of Tb-based RE–TM ferrimagnetic [Tbx(FeCo)1−x] thin films. We find that the Tb concentration at which the magnetic moments of the RE- and TM- sublattices compensate increases with decreasing film thickness when the films are grown on Pt underlayers. For the thinnest TbFeCo films (1.5 nm-thick), the magnetic compensation is not observed at room temperature, suggesting that the Tb atoms do not contribute to the magnetization. In these thin films, the perpendicular magnetic anisotropy (PMA) increases when a thin Co layer is inserted, while it drops to zero when a thin Tb layer is inserted. Such contrasting behavior reveals that the PMA originates from the Pt/Co interface. The Tb concentration at which magnetic compensation occurs decreases when the underlayer is changed from Pt to Ta. We infer that Tb becomes magnetically inactive due to intermixing with the Pt underlayer, causing the reduction in PMA.
Nonlinear optical limiting property and carrier dynamics in tin phthalocyanine porous organic frameworks
Authors: Li Yuren , Yan Lihe , Si Jinhai , Liang Zezhou , Huang Wenbo , Ma Heping , Hou Xun
Published: January 2022

The nonlinear optical limiting (OL) property of tin phthalocyanine porous organic frameworks (Sn-Pc-POFs) dispersion in the nanosecond regime was studied, which showed excellent dispersibility and stability as well as a low OL threshold. To clarify the nonlinear optical response mechanisms in the material, the energy level structure of Sn-Pc-POFs was simulated using the density functional theory calculation, and the photoinduced carrier dynamics was studied using femtosecond time-resolved transient absorption spectroscopy. The results indicated that the large absorption cross section and long lifetime of the excited state were responsible for the excellent OL property of the material.
Experiment and modeling of the pulsed lasing in a diode-pumped argon metastable laser
Authors: Wang Rui , Yang Zining , Li Kang , Wang Hongyan , Xu Xiaojun
Published: January 2022

Diode-pumped metastable rare gas lasers are showing their potential for high-energy laser systems with intensive investigations carried out to understand their lasing characteristics. Here, we demonstrated pulsed lasing of a diode-pumped argon metastable laser based on a pulsed DC glow discharge in argon and helium mixtures for different discharge voltages and pressures. A transient rate equation model was established and solved to explain the cause of the pulsed lasing in our experiment. The insufficient production rate of argon metastable atoms (1s5) and the slow transfer rate out of the 1s4 state in the plasma during the lasing process were found to be the key reasons. This work may shed some light on the future design of plasma sources that have higher metastable atom production rates to achieve highly efficient continuous wave lasing.