bluuebunny/crossref_metadata_2025 huggingface dataset:
Statistical analysis of observed Faraday wave patterns
Authors: Peña-Polo Franklin , Carvajal-Mariscal Ignacio , Vargas Carlos A. , Di G. Sigalotti Leonardo
Published: June 2023

We present experimental observations of Faraday wave patterns when a liquid in a square recipient is submitted to vertical vibrations with forcing frequencies and amplitudes in the intervals 10 ≤ F ≤ 80 Hz and 0.1 ≤ A ≤ 3 mm, respectively. A sweep of the forcing parameter space is performed to investigate the surface patterns that form for two different sizes of the recipient. The waveforms are obtained by means of a Pearson correlation analysis of a sequence of liquid surface images for each experiment. The Pearson correlation coefficients are then fast Fourier transformed to obtain the power spectra. For 10 ≤ F ≤ 15 Hz, tessellation patterns consisting of ordered arrays of rhomboid-shaped tiles are observed; whereas, for 20 ≤ F ≤ 25, the tessellation patterns become irregular over the entire surface where square, rhomboidal, andhexagonal tilings coexist. At 30 ≤ F ≤ 45 Hz, the patterns correspond to a mixed state where ordered and irregular quadrilateral tessellation patterns coexist. At frequencies between 50 and 80 Hz, the tessellated patterns that form consist of irregularly distributed square-shaped tiles. In all cases, the excited waves are periodic with a dominant subharmonic frequency f = F/2. However, for given forcing parameters, the waveforms and their amplitudes differ markedly when the size of the recipient is changed.
Perceptions of the effectiveness of using patient encounter data as an education and reflection tool in general practice training
Authors: Klein Linda , Bentley Michael , Moad Dominica , Fielding Alison , Tapley Amanda , van Driel Mieke , Davey Andrew , Mundy Ben , FitzGerald Kristen , Taylor Jennifer , Norris Racheal , Holliday Elizabeth , Magin Parker
Published: June 2023

Introduction Patient encounter tools provide feedback and potentially reflection on general practitioner (GP) registrars’ in-practice learning and may contribute to the formative assessment of clinical competencies. However, little is known about the perceived utility of such tools. Aim To investigate the perceived utility of a patient encounter tool by GP registrars, their supervisors, and medical educators (MEs). Methods General practice registrars, supervisors and MEs from two Australian regional training organisations completed a cross-sectional questionnaire. Registrars rated how Registrar Clinical Encounters in Training (ReCEnT), a patient encounter tool, influenced their reflection on, and change in, clinical practice, learning and training. Supervisors’ and MEs’ perceptions provided contextual information about understanding their registrars’ clinical practice, learning and training needs. Results Questionnaires were completed by 48% of registrars (n = 90), 22% of supervisors (n = 182), and 61% of MEs (n = 62). Most registrars agreed that ReCEnT helped them reflect on their clinical practice (79%), learning needs (69%) and training needs (72%). Many registrars reported changing their clinical practice (54%) and learning approaches (51%). Fewer (37%) agreed that ReCEnT influenced them to change their training plans. Most supervisors (68%) and MEs (82%) agreed ReCEnT reports helped them better understand their registrars’ clinical practice. Similarly, most supervisors (63%) and MEs (68%) agreed ReCEnT reports helped them better understand their registrars’ learning and training needs. Discussion ReCEnT can prompt self-reflection among registrars, leading to changes in clinical practice, learning approaches and training plans. Reaching its potential as an assessment for learning (as opposed to an assessment of learning) requires effective engagement between registrars, their supervisors and MEs.
Dissipative phase transition in an open Tavis–Cummings model with a two-photon drive
Authors: Adhikary Kingshuk , Müstecaplıoǧlu Özgür E , Deb Bimalendu
Published: June 2023

We investigate the steady-state quantum phases and associated collective phenomena of an open Tavis–Cummings (TC) model driven by a two-photon source. The standard (non-dissipative) TC model describes the quantum phases of an ensemble of N

q
two-level quantum emitters interacting with a single-mode electromagnetic field. The interplay among coherent driving, dissipation, and dipole interactions of the open TC model results in emergent collective phenomena, leading to a dissipative or non-equilibrium phase transition from the normal to the superradiant phase. We solve the Liouvillian equation analytically using the semi-classical mean-field approximation. We carry out stability analysis of the steady-state phases and determine the phase boundary. The use of Holstein–Primakoff transformation in the thermodynamic limit

N
q

→
∞

reduces the system to an effective coupled-oscillator model, the solution of which yields collective modes.
Plasmon enhancement of third-order nonlinear optical absorption of gold nanoparticles dispersed in planar oriented nematic liquid crystals
Authors: Wang Shengwei , Fu Changshuo , Sun Greg , Gharbi Mohamed Amine , Yelleswarapu Chandra S
Published: June 2023

We report structural and nonlinear optical properties of 20 nm gold (Au) nanoparticles (NPs) that are dispersed in planar degenerate (non-oriented) and planar oriented nematic liquid crystals (LCs) (4′-Pentyl-4-biphenylcarbonitrile-5CB). Taking advantage of elastic forces in the planar oriented nematic LC, we aligned AuNPs parallel to the 5CB director axis. In the case of planar degenerate, 5CB is not aligned and has no preferred orientation, forcing the AuNPs to disperse randomly. Results show that the linear optical absorption coefficient for the planar oriented 5CB/AuNPs mixture is larger than the corresponding planar degenerate sample. The nonlinear absorption coefficients are greatly enhanced in planar oriented samples at relatively high concentrations which can be attributed to plasmon coupling between the aligned AuNPs. This study demonstrates the utility of LCs for developing the assembly of NPs with enhanced optical properties which may offer important insight and technological advancement for novel applications, including photonic nanomaterials and optoelectronic devices.
Superlattice-like Sb70Se30/HfO2 thin films for high thermal stability and low power consumption phase change memory
Authors: Wang Kangyao , Chen Leng
Published: June 2023

We have fabricated Sb70Se30/HfO2 superlattice-like structure thin films for phase change memory by magnetron sputtering method, and investigated the effect of the HfO2 layer on the crystalline characteristics and phase change behavior of Sb70Se30/HfO2 thin films. The experimental results show that as the HfO2 thickness increases, the crystallization temperature rises, the data retention capacity increases as well as the band gap widens, which is beneficial for improving the thermal stability and reliability of Sb70Se30/HfO2 thin films. It was also found that the HfO2 composite layer inhibited the grain growth of the Sb70Se30 thin film, reducing the grain size and resulting in a smoother surface. In addition, the volume fluctuation of the Sb70Se30/HfO2 thin films changes by only 5.58% between amorphous and crystalline. The threshold and reset voltages of the cell based on Sb70Se30/HfO2 thin films are 1.52 V and 2.4 V respectively. We found that the HfO2 composite layer plays a significant role in improving thermal stability, refining grain size of Sb70Se30 phase change films and reducing device power consumption.
Investigation into the effects of hydrophobicity on thermohydraulic characteristics and entropy generation of hybrid nanofluid with the magnetic property in a micro-heat sink under a magnetic field
Authors: Derikvand Mohammad , Salehi Ali Akbar , Solari Mojtaba Shams , Najafi Fatemeh
Published: June 2023

The cooling of devices is a big challenge in the electronics industry, and most process units (graphical are central process units) experience defects under harsh temperature conditions, so dissipating generated heat under various working conditions should be studied seriously. This study investigates the magnetohydrodynamics of hybrid ferro-nanofluids in the presence of hydrophobic surfaces in a micro-heat sink. To scrutinize this study, a finite volume method (FVM) is applied. The ferro-nanofluid includes water as a base fluid and multiwall carbon nanotubes (MWCNTs) and Fe3O4 as nanoadditives, which are used in three concentrations (0, 1, and 3%). Other parameters such as the Reynolds number (5–120), Hartmann number (magnitude of the magnetic field from 0 to 6), and hydrophobicity of surfaces are scrutinized for their impacts on heat transfer and hydraulic variables as well as entropy generation variables. The outcomes indicate that increasing the level of hydrophobicity in surfaces leads simultaneously to improved heat exchange and reduced pressure drop. Likewise, it decreases the frictional and thermal types of entropy generation. Intensifying the magnitude of the magnetic field enhances the heat exchange as much as the pressure drop. It can also decrease the thermal term in entropy generation equations for the fluid, but increase the frictional entropy generation and adds a new term, magnetic entropy generation. Incrementing the Reynolds number improves the convection heat transfer parameters, although it intensifies the pressure drop in the length of the channel. Also, the thermal entropy generation and frictional entropy generation decrease and increase with an increasing flow rate (Reynolds number).
Graphene's effect and mechanism on the properties of alkali-activated slag coating
Authors: Wang Siming , Luo Xiang , Hua Sudong , Zhang Yanan , Chen Tingzhu
Published: June 2023

Using alkali-activated slag to prepare coatings is an alternative solution for concrete repair and protection. However, shrinkage cracking limits the application of alkali-activated slag, which also increases the risk of coating peeling. Graphene dispersions (content of 0.2%, 0.4%, 0.6% and 0.8%) were added to the alkali-activated slag coatings. The drying time, apparent circumstance (thicknesses of 1 mm, 2 mm, 3 mm and 5 mm) and the tensile bond strength with 1 mm thickness coating were determined. The mechanism of action was analyzed in terms of both product and interfacial properties. The experimental results showed that the graphene dispersion would shorten the drying time of the coatings. The drying time was reduced by 57.1% (from 116 min to 52 min). Moreover, the graphene dispersion improves the cracking of the coating. The larger the coating thickness is, the better it improves the cracking effect. The surface cracking of the coating with 5 mm thickness was reduced by 60.7% (from 1.6751% to 0.6583%). Graphene can significantly improve the bond strength of the coating. When the graphene content is 0.8%, the bonding strength with a thickness of 1 mm is 0.502 MPa at 7 days and 1.577 MPa at 28 days. The bond strength increased by 280.3% and 175.2%, respectively, XRD, FTIR and SEM analysis showed that the increase in bond strength was caused by two factors. (1) Graphene can promote the generation of zeolite phase in alkali-activated slag. This is conducive to enhancing the interlayer adhesion of the coating itself. (2) Graphene is beneficial to reduce the pores in the transition zone between the coating and the substrate and enhance the contact area between the coating and the substrate and makes the transition zone denser.
CYJAX: A package for Calabi-Yau metrics with JAX
Authors: Gerdes Mathis , Krippendorf Sven
Published: June 2023

We present the first version of CYJAX, a package for machine learning Calabi–Yau metrics using JAX. It is meant to be accessible both as a top-level tool and as a library of modular functions. CYJAX is currently centered around the algebraic ansatz for the Kähler potential which automatically satisfies Kählerity and compatibility on patch overlaps. As of now, this implementation is limited to varieties defined by a single defining equation on one complex projective space. We comment on some planned generalizations.

More documentation can be found at: https://cyjax.readthedocs.io.

The code is available at: https://github.com/ml4physics/cyjax.
Cardiogenic shock and severe secondary mitral regurgitation successfully treated with transcatheter edge-to-edge repair: a case report
Authors: Shabbir Muhammad Asim , Tiwari Nidhish , Burdorf Adam , Moulton Michael , Velagapudi Poonam
Published: June 2023

Background

Cardiogenic shock (CS) associated with severe mitral regurgitation (MR) forebodes a high risk of morbidity and mortality. Transcatheter edge-to-edge repair (TEER) is a rapidly evolving technique for severe MR in haemodynamically stable patients. However, the safety and efficacy of TEER for severe MR in CS are not well established.

Case summary

An 83-year-old male presented with dyspnoea and was hospitalized for heart failure. Chest X-ray revealed pulmonary oedema. Transthoracic echocardiography showed severely depressed ejection fraction (EF) with severe secondary MR. Right heart catheterization confirmed a low cardiac index. Diuretics and inotropes were administered. Due to persistent hypotension, we could not wean inotropes. The patient was deemed high risk for surgery by the heart team, and a decision was made to proceed with TEER with MitraClip. Under transoesophageal echocardiography and fluoroscopic guidance, two MitraClips were deployed sequentially. The MR grade was reduced to two mild jets subsequently. The patient was weaned off inotropes and eventually discharged. At the 30-day follow-up, he was participating in physical activities such as golf.

Discussion

Cardiogenic shock complicated by severe MR carries high mortality. With severe MR, the forward stroke volume is lower than the stated EF leading to poor organ perfusion. Inotropes and/or mechanical circulatory support devices are paramount for initial stabilization; however, they do not treat underlying MR. Transcatheter edge-to-edge repair with MitraClip has been shown to improve survival in CS patients with severe MR in observational studies. However, prospective trials are lacking. Our case demonstrates the utility of MitraClip to treat severe secondary MR refractory to medical therapy in a CS patient. The heart team must evaluate risks and benefits of this therapy in CS patients.
Global transonic solution of hot accretion flow with thermal conduction
Authors: Mitra Samik , Ghoreyshi Sayyedeh Masoumeh , Mosallanezhad Amin , Abbassi Shahram , Das Santabrata
Published: June 2023

We examine the effect of thermal conduction on the low-angular momentum hot accretion flow (HAF) around non-rotating black holes accreting mass at very low rate. While doing so, we adopt the conductive heat flux in the saturated form, and solve the set of dynamical equations corresponding to a steady, axisymmetric, viscous, advective accretion flow using numerical methods. We study the dynamical and thermodynamical properties of accreting matter in terms of the input parameters, namely energy (ε0), angular momentum (ℓ0), viscosity parameter (α), and saturation constant (Φs) regulating the effect of thermal conduction. We find that Φs plays a pivotal role in deciding the transonic properties of the global accretion solutions. In general, when Φs is increased, the critical point (rc) is receded away from the black hole, and flow variables are altered particularly in the outer part of the disc. To quantify the physically acceptable range of Φs, we compare the global transonic solutions with the self-similar solutions, and observe that the maximum saturation constant ($\Phi ^{\rm max}_{\rm s}$) estimated from the global solutions exceeds the saturated thermal conduction limit (Φsc) derived from the self-similar formalism. Moreover, we calculate the correlation between α and $\Phi ^{\rm max}_{\rm s}$ and find ample disagreement between global solutions and self-similar solutions. Further, using the global flow variables, we compute the Bernoulli parameter (Be) which remains positive all throughout the disc, although flow becomes loosely unbound for higher Φs. Finally, we indicate the relevance of this work in the astrophysical context in explaining the possibility of mass-loss/outflows from the unbound disc.
Comparative Efficacy and Safety of Five Anti-calcitonin Gene-related Peptide Agents for Migraine Prevention
Authors: Sun Wenfang , Cheng Hua , Xia Binbin , Liu Xianjun , Li Yali , Wang Xuemei , Liu Chengjiang
Published: June 2023

Objectives:

Anti-calcitonin gene-related peptide (CGRP) agents are some of the newest preventive medications for migraine. There is limited literature comparing the efficacy of the most recent CGRP antagonist, atogepant, to CGRP monoclonal antibodies for migraine prevention. In this network meta-analysis, the efficacy and safety of migraine treatments including different doses of atogepant and CGRP monoclonal antibodies were evaluated to provide a reference for future clinical trials.

Materials and Methods:

A search using PubMed, Embase, and Cochrane Library identified all randomized controlled trials published through May 2022 and including patients diagnosed with episodic or chronic migraine and treated with erenumab, fremanezumab, eptinezumab, galcanezumab, atogepant, or placebo. The primary outcomes were the reduction of monthly migraine days, 50% response rate, and the number of adverse events (AEs). The Cochrane Collaboration tool was used to assess the risk of bias.

Results:

In this study, 24 articles were considered for analysis. Regarding efficacy, all interventions were superior to placebo with a statistically significant difference. The most effective intervention was monthly fremanezumab 225 mg in change from baseline of migraine days (standard mean difference = −0.49, 95% CI: −0.62, −0.37) and 50% response rate (risk ratio = 2.98, 95% CI: 2.16,4.10), while the optimal choice for reducing acute medication days was monthly erenumab 140 mg (standard mean difference = −0.68, 95% CI: −0.79, −0.58). In terms of AEs, all therapies and placebo did not achieve statistical significance except for monthly galcanezumab 240 mg and quarterly fremanezumab 675 mg. There was no significant difference in discontinuation due to AEs between interventions and placebo.

Discussion:

All anti-CGRP agents were more effective than placebo in migraine prevention. Overall, monthly fremanezumab 225 mg, monthly erenumab 140 mg, and daily atogepant 60 mg were effective interventions with fewer side effects.
Association Between Postoperative Methocarbamol and Postoperative Pain Opioid Dose Requirements
Authors: Komatsu Ryu , Singleton Michael D. , Wu Jiang , Dinges Emily M. , Bollag Laurent A.
Published: June 2023

Objectives:

We tested the hypothesis that patients who received methocarbamol postoperatively experience less severe pain and require smaller doses of opioids than those who did not receive methocarbamol.

Materials and Methods:

This is a retrospective cohort study of patients undergoing surgery involving the musculoskeletal system. Of 9089 patients, 704 received methocarbamol during 48 hours postoperatively, while 8385 did not receive methocarbamol. The patients who received methocarbamol postoperatively and the patients who did not receive methocarbamol were compared on the time-weighted average (TWA) pain score and opioid dose requirements in morphine milligram equivalents (MME) during the first 48 hours postoperatively, using propensity score-weighted regression models to adjusting for preoperative and intraoperative covariates.

Results:

Postoperative 48-hour TWA pain scores were 5.5±1.7 (mean±SD), and 4.3±2.1 for methocarbamol and non-methocarbamol patients. Postoperative 48-hour opioid dose requirements in MME were 276 [170–347] (median [interquartile range (IQR)]) mg, and 190 [60–248] mg for methocarbamol and non-methocarbamol patients. In propensity score-weighted regression models, receiving methocarbamol postoperatively was associated with 0.97-point higher postoperative TWA pain score (95% CI, 0.83–1.11; P<0.001), and 93.6-MME higher postoperative opioid dose requirements (95% CI, 79.9 to 107.4; P<0.001), compared with not receiving methocarbamol postoperatively.

Discussion:

Postoperative methocarbamol was associated with significantly higher acute postoperative pain burden and opioid dose requirements. Although the results of the study are influenced by residual confounding, they suggest a limited—if any—benefit of methocarbamol as an adjunct of postoperative pain management.
Donor Endothelial Cell Density Not Changed Immediately After Ex Vivo Corneal Cross-Linking
Authors: De Arrigunaga Sofia , Benetz Beth Ann , Farazdaghi Sameera , Lass Jonathan H. , Zhao Yan , Zurakowski David , Ciolino Joseph B.
Published: June 2023

Purpose:

The aim of this study was to evaluate the effect of corneal cross-linking on central endothelial cell density (ECD) by comparing masked measurements before and immediately after preparation of cross-linked (CXL) and non–cross-linked (non-CXL) donor corneas.

Methods:

Thirty donor corneas were randomized 1:1 to either CXL or non-CXL using a modified Dresden protocol. Specular microscopic images of the central corneal endothelium were obtained within 36 hours of recovery and within 3 hours of preparation completion. Images were sent to a central cornea image analysis reading center for ECD determination in a masked, dual-graded manner.

Results:

Before and after preparation, the mean ECD was 2567 ± 305 cells/mm2 and 2525± 339 cells/mm2 for the CXL group (n =15) and 2652 ± 365 cells/mm2 and 2572 ± 513 cells/mm2 for the non-CXL group (n =15), respectively. The mean difference in ECD before and after preparation was not statistically significant for the CXL and non-CXL groups (P = 0.36; P = 0.31, respectively). In addition, an independent sample t test showed no statistically significant difference in the ECD change between the CXL and non-CXL groups (P = 0.67).

Conclusions:

Our specular microscopic findings show that ex vivo cross-linking of donor corneas does not seem to produce acute decrease of central endothelial cell density. These findings are encouraging and assist in warranting a clinical trial examining its value in reducing refractive errors and improving postoperative visual outcomes in eyes with keratoconus that undergo keratoplasty.
Pregnancy Outcomes Associated with Ovarian Hyperstimulation Syndrome: A Retrospective Cohort Study of Infertile Women
Authors: Sangtani Ajleeta , Ismail Maryama , Weaver Amy , Khan Zaraq
Published: June 2023

Objective

To assess the relationship between ovarian hyperstimulation syndrome (OHSS) and adverse outcomes using population-based data in the United States. The hypothesis is that patients with OHSS were more likely to deliver preterm and more likely to have hypertensive disorders.

Methods

This retrospective cohort study identified 94 patients with OHSS and 183 matched referents in eight counties in Minnesota. Data were collected regarding pregnancy history, infertility treatment, and pregnancy outcomes. Using the Rochester Epidemiology Project, study subjects were identified from female patients, aged 18 to 49 years, who were diagnosed with infertility from January 2, 1995 to December 1, 2017, and had a pregnancy greater than 20 weeks' gestation. The primary outcome was preterm delivery or hypertensive disorder of pregnancy incidence in the OHSS group when compared with control patients. Chi-squared test, t test, and multivariate logistic models were used where appropriate.

Results

Patients with OHSS were more likely to deliver preterm (odds ratio, 2.14; 95% confidence interval, 1.26–3.65; P < 0.01), and their neonates were more likely to be small for gestational age (odds ratio, 4.78; 95% confidence interval, 1.61–14.19; P < 0.01). No significant differences between the groups were observed in any other outcome. Patients with OHSS are more likely to deliver preterm if they undergo fresh transfer compared with a freeze all and subsequent frozen transfer (odds ratio, 3.03, 95% confidence interval, 1.20–7.66, P = 0.02).

Conclusion

OHSS may lead to preterm birth and small-for-gestational-age neonates, which changes patient counseling and leads to arranging specialized obstetrical care for these patients with OHSS.
Early Complications after Prepectoral Tissue Expander Placement in Breast Reconstruction with and without Acellular Dermal Matrix
Authors: Pires Giovanna , Marquez Jessica L. , Memmott Stanley , Sudduth Jack D. , Moss Whitney , Eddington Devin , Hobson Gregory , Tuncer Fatma , Agarwal Jayant P. , Kwok Alvin C.
Published: June 2023

Background:

Prepectoral breast reconstruction has become popularized with the concurrent use of acellular dermal matrix (ADM). The authors sought to compare 3-month postoperative complication rates and explantation rates for first-stage, tissue-expander–based, prepectoral breast reconstruction with and without the use of ADM.

Methods:

A single-institution retrospective chart review was performed to identify consecutive patients undergoing prepectoral tissue-expander–based breast reconstruction from August of 2020 to January of 2022. Chi-square tests were used to compare demographic categorical variables, and multiple variable regression models were used to identify variables associated with 3-month postoperative outcomes.

Results:

The authors enrolled 124 consecutive patients. Fifty-five patients (98 breasts) were included in the no-ADM cohort and 69 patients (98 breasts) were included in the ADM cohort. There were no statistically significant differences between the ADM and no-ADM cohorts with regard to 90-day postoperative outcomes. On multivariable analysis, there were no independent associations between seroma, hematoma, wound dehiscence, mastectomy skin flap necrosis, infection, unplanned return to the operating room, or explantation in the ADM and no-ADM groups after controlling for age, body mass index, history of diabetes, tobacco use, neoadjuvant chemotherapy, and postoperative radiotherapy.

Conclusions:

The authors’ results reveal no significant differences in odds of postoperative complications, unplanned return to the operating room, or explantation between the ADM and no-ADM cohorts. More studies are needed to evaluate the safety of prepectoral, tissue expander placement without ADM.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Inclusion, diversity, access, and equity in antimicrobial stewardship: where we are and where we are headed
Authors: Cichon Catherine J. , Green Evangeline C. , Hilker Eric , Marcelin Jasmine R.
Published: June 2023

Purpose of review

This review summarizes existing data on health inequities in antimicrobial stewardship, identifies data gaps and barriers, and reflects on mitigating factors for achieving inclusion, diversity, access, and equity in antimicrobial stewardship.

Recent findings

Studies show variable antimicrobial prescribing patterns and adverse events according to race/ethnicity, rurality, socioeconomic status, and other factors. Most studies demonstrating these inequities typically do not address their upstream drivers or interventions to mitigate them.

Approaching antimicrobial stewardship through a lens of equity can allow antimicrobial stewardship programs (ASPs) opportunities to reach a wider population, and in doing so reduce health inequities. These opportunities include expanding ASPs beyond highly resourced institutions, educational outreach efforts, equity monitoring tools, incentivized equity metrics, and leadership diversification. Clinical research in this area also needs to address drivers of inequities and innovative approaches to mitigating and reducing them.
The Effects of Virtual Reality Glasses on Vital Signs and Anxiety in Patients Undergoing Colonoscopy
Authors: Doğan Yılmaz Esra , Ünlüsoy Dinçer Nigar
Published: June 2023

Colonoscopy is a painful procedure that causes anxiety and changes in vital signs. Pain and anxiety may cause patients to avoid colonoscopy, which is a preventive and curative healthcare service. The aim of this study was to examine the effects of virtual reality glasses on the vital signs (blood pressure, pulse, respiration, oxygen saturation, and pain) and anxiety in patients undergoing colonoscopy. The population of the study consisted of 82 patients who underwent colonoscopy without sedation between January 2, 2020, and September 28, 2020. Post-power analysis was performed with 44 patients who agreed to participate in the study, met the inclusion criteria, and were followed up for pre- and post-tests. The experimental group participants (n = 22) watched a 360° virtual reality video through virtual reality glasses whereas the control group participants (n = 22) underwent a standard procedure. Data were collected using a demographic characteristics questionnaire, the Visual Analog Scale-Anxiety, Visual Analog Scale-Pain, Satisfaction Evaluation Form, and monitoring of vital signs. The experimental group participants had significantly lower levels of pain, anxiety, systolic blood pressure, and respiratory rate and significantly higher peripheral oxygen saturation during colonoscopy than the control group participants. The majority of the experimental group participants were satisfied with the application. Virtual reality glasses have a positive effect on vital signs and anxiety during colonoscopy.
A new view of axon growth and guidance grounded in the stochastic dynamics of actin networks
Authors: Forghani Rameen , Chandrasekaran Aravind , Papoian Garegin , Giniger Edward
Published: June 2023

The mechanism of axon growth and guidance is a core, unsolved problem in neuroscience and cell biology. For nearly three decades, our view of this process has largely been based on deterministic models of motility derived from studies of neurons culturedin vitroon rigid substrates. Here, we suggest a fundamentally different, inherently probabilistic model of axon growth, one that is grounded in the stochastic dynamics of actin networks. This perspective is motivated and supported by a synthesis of results from live imaging of a specific axon growing in its native tissuein vivo, together with single-molecule computational simulations of actin dynamics. In particular, we show how axon growth arises from a small spatial bias in the intrinsic fluctuations of the axonal actin cytoskeleton, one that produces net translocation of the axonal actin network by differentially modulating local probabilities of network expansion versus compaction. We discuss the relationship between this model and current views of axon growth and guidance mechanism and demonstrate how it offers explanations for various longstanding puzzles in this field. We further point out the implications of the probabilistic nature of actin dynamics for many other processes of cell morphology and motility.
Study on preparation and sintering properties of nano-silver-coated tin slurry
Authors: Yang Hui , You Huan
Published: June 2023

A nano-sized silver-coated tin (Sn@Ag) slurry was prepared by heterogeneous flocculation method by adjusting the pH value of solution and selecting different dispersants. The slurry improved the oxidation resistance of tin and its dispersibility in silver matrix. The sintering strength of nanometre Sn@Ag slurry increases with the increase of Sn content. When the Sn content reaches 5%, the shear strength of the joint reaches the highest 50 MPa, which is more than 10 MPa higher than that of the pure nanometre silver slurry sintered joint. The increase of shear strength is due to the fact that the equilibrium phase formed after sintering is Ag–Sn replacement solid solution and intermetallic compound Ag
3
Sn, which have the effect of replacement solution strengthening and dispersion strengthening, respectively. It is proved by experiments and analysis that the application of nano-silver paste in chip interconnection is feasible. The research of this subject provides experimental reference and theoretical basis for the application of new generation interconnect materials in power devices and promotes the development of microelectronics packaging technology.
Secondary ion mass spectrometry, a powerful tool for revealing ink formulations and animal skins in medieval manuscripts
Authors: Gravis David , Roy Nicolas , Ruffini-Ronzani Nicolas , Houssiau Laurent , Felten Alexandre , Tumanov Nikolay , Deparis Olivier
Published: June 2023

Book production by medieval scriptoria have gained growing interest in recent studies. In this context, identifying ink compositions and parchment animal species from illuminated manuscripts is of great importance. Here, we introduce time-of-flight secondary ion mass spectrometry (ToF-SIMS) as a non-invasive tool to identify both inks and animal skins in manuscripts, at the same time. For this purpose, both positive and negative ion spectra in inked and non-inked areas were recorded. Chemical compositions of pigments (decoration) or black inks (text) were determined by searching for characteristic ion mass peaks. Animal skins were identified by data processing of raw ToF-SIMS spectra using principal component analysis (PCA). In illuminated manuscripts from the fifteenth to sixteenth century, malachite (green), azurite (blue), cinnabar (red) inorganic pigments, as well as iron-gall black ink, were identified. Carbon black and indigo (blue) organic pigments were also identified. Animal skins were identified in modern parchments of known animal species by a two-step PCA procedure. We believe the proposed method will find extensive application in material studies of medieval manuscripts, as it is non-invasive, highly sensitive and able to identify both inks and animal skins at the same time, even from traces of pigments and tiny scanned areas.
Revisiting the HO
●
-initiated oxidation of L-proline amino acid in the aqueous phase: influence of transition metal ions
Authors: Truong Dinh Hieu , Lan Nguyen Thi Huong , Dao Duy Quang
Published: June 2023

The oxidation of L-proline (Pro) by HO
●
radical in water and the influence of transition metal ions on this process has been revisited by using the density functional theory (DFT) method at the M05-2X/6-311 + + G(3df,3pd)//M05-2X/6-311 + + G(d,p) level of theory at the temperature of 298.15 K. The main reactive sites of the HO
●
–initiated oxidation of Pro via hydrogen atom transfer (HAT) reactions are at the β- and γ-carbon, with the branching ratios being 44.6% and 39.5%, respectively. The overall rate constant at 298.15 K is 6.04 × 10
8
M
−1
s
−1
. In addition, Pro tends to form stable complexes with both Fe and Cu ions via the –COO functional group of dipole-salt form. The most stable Cu(II)-Pro complexes have high oxidant risks in enhancing the HO
●
formation in the presence of reducing agents. Besides this, the high oxidation state metal complexes, i.e. Fe(III)-Pro and Cu(II)-Pro, may be oxidized by HO
●
radical via HAT reactions but with a lower rate constant than that of free-Pro. By contrast, the low oxidation state metal complexes (i.e. Fe(II)-Pro and Cu(I)-Pro) have higher oxidation risks than the free ligands, and thus, the complexation enhances the oxidation of Pro amino acid.
A Cu
2+
triggered reversible photochromic system: the structure photochromic response relationship study and potential applications
Authors: Wang Shuping , Wu Lumiao , Li He , Zhang Guoyan , Wei Xueqian , Zheng Jiyi , Jiang Long , Ju Ping , Qu Fengli , Zhang Ensheng
Published: June 2023

Fifteen rhodamine B hydrazide hydrazone (RhBHH) derivatives (compounds

a

–

o

) with various substituent groups at different position and their photochromic property triggered by Cu
2+
were studied to illustrate the structure photochromic response relationship (SPRR). Three of them (compounds

f

–

h

) with a
para
-position hydroxyl group and two
meta
-position halogen substituents display Cu
2+
-triggered photochromic which is significantly different from the previous reports. It was found that halogen atoms, which were generally considered to have no remarkable regulation effect, exhibited great influences on the photochromic behaviour of RhBHH derivatives. Detail photochromic properties of the developed photochromic system were revealed by using compound

g

as the model substrate, and only Cu
2+
displayed high selective trigger effect. Good reversible photochromic phenomenon was observed after stimulated with visible light irradiation and dark (or heat) bleaching consecutively. Furthermore, this photochromic system could be used in the preparation of photochromic glass, special security ink, molecular logic gate and two-dimensional code for security information storage.
Extending
Q
-learning to continuous and mixed strategy games based on spatial reciprocity
Authors: Wang Lu , Zhang Long , Liu Yang , Wang Zhen
Published: June 2023

The discrete strategy game, in which agents can only choose cooperation or defection, has received lots of attention. However, this hypothesis seems implausible in the real world, where choices may be continuous or mixed. Furthermore, when applying

Q

-learning to continuous or mixed strategy games, one of the challenges is that the learning space grows drastically as the number of states and actions rises. So, in this article, we redesign the

Q

-learning method by considering the spatial reciprocity, in which agents simply interact with their four neighbours to get the reward and learn the action by taking neighbours’ strategy into account. As a result, the learning state and action space is transformed into a

5
×
5

table that stores the state and action of the focal agent and its four neighbours, avoiding the curse of dimensionality caused by a continuous or mixed strategy game. The numerical simulation results reveal the striking differences between the three classes of games. In detail, the discrete strategy game is more vulnerable to the setting of relevant parameters, whereas the other two strategy games are relatively stable. At the same time, in terms of promoting cooperation, a mixed strategy game is always better than a continuous one.
Geometric mechanics of ordered and disordered kirigami
Authors: Chaudhary G. , Niu L. , Han Q. , Lewicka M. , Mahadevan L.
Published: June 2023

The presence of incomplete cuts in a thin planar sheet can dramatically alter its mechanical and geometrical response to loading, as the cuts allow the sheet to deform strongly in the third dimension, most beautifully demonstrated in kirigami art-forms. We use numerical experiments to characterize the geometric mechanics of kirigamized sheets as a function of the number, size and orientation of cuts. We show that the geometry of mechanically loaded sheets can be approximated as a composition of simple developable units: flats, cylinders, cones and compressed Elasticae. This geometric construction yields scaling laws for the mechanical response of the sheet in both the weak and strongly deformed limit. In the ultimately stretched limit, this further leads to a theorem on the nature and form of geodesics in an arbitrary kirigami pattern, consistent with observations and simulations. Finally, we show that by varying the shape and size of the geodesic in a kirigamized sheet, we can control the deployment trajectory of the sheet, and thence its functional properties as an exemplar of a tunable structure that can serve as a robotic gripper, a soft light window or the basis for a physically unclonable device. Overall our study of disordered kirigami sets the stage for controlling the shape and shielding the stresses in thin sheets using cuts.
Fractal structure of human and primate social networks optimizes information flow
Authors: West Bruce J. , Culbreth Garland , Dunbar Robin I. M. , Grigolini Paolo
Published: June 2023

Primate and human social groups exhibit a fractal structure that has a very limited range of preferred layer sizes, with groups of 5, 15, 50 and (in humans) 150 and 500 predominating. In non-human primates, this same fractal distribution is also observed in the distribution of species mean group sizes and in the internal network structure of their groups. Here we demonstrate that this preferential numbering arises because of the critical nature of dynamic self-organization within complex social networks. We calculate the size dependence of the scaling properties of complex social network models and argue that this aggregate behaviour exhibits a form of collective intelligence. Direct calculation establishes that the complexity of social networks as measured by their scaling behaviour is non-monotonic, peaking globally around 150 with a secondary peak at 500 and tertiary peaks at 5, 15 and 50. This provides a theory-based rationale for the fractal layering of primate and human social groups.
How to generate and test hypotheses about colour: insights from half a century of guppy research
Authors: Kemp Darrell J. , Reznick David N. , Arendt Jeffrey , van den Berg Cedric , Endler John A.
Published: June 2023

Coloration facilitates evolutionary investigations in nature because the interaction between genotype, phenotype and environment is relatively accessible. In a landmark set of studies, Endler addressed this complexity by demonstrating that the evolution of male Trinidadian guppy coloration is shaped by the local balance between selection for mate attractiveness versus crypsis. This became a textbook paradigm for how antagonistic selective pressures may determine evolutionary trajectories in nature. However, recent studies have challenged the generality of this paradigm. Here, we respond to these challenges by reviewing five important yet underappreciated factors that contribute to colour pattern evolution: (i) among-population variation in female preference and correlated variation in male coloration, (ii) differences in how predators versus conspecifics view males, (iii) biased assessment of pigmentary versus structural coloration, (iv) the importance of accounting for multi-species predator communities, and (v) the importance of considering the multivariate genetic architecture and multivariate context of selection and how sexual selection encourages polymorphic divergence. We elaborate these issues using two challenging papers. Our purpose is not to criticize but to point out the potential pitfalls in colour research and to emphasize the depth of consideration necessary for testing evolutionary hypotheses using complex multi-trait phenotypes such as guppy colour patterns.
How much cultural variation around the globe is explained by ecology?
Authors: Wormley Alexandra S. , Kwon Jung Yul , Barlev Michael , Varnum Michael E. W.
Published: June 2023

How much cultural variation is explained by the physical and social ecologies people inhabit? Here, we provide an answer using nine ecological variables and 66 cultural variables (including personality traits, values and norms) drawn from the EcoCultural Dataset. We generate a range of estimates by using different statistical metrics (e.g. current levels, average levels across time, unpredictability across time) of each of the ecological variables. Our results suggest that, on average, ecology explains a substantial amount of human cultural variation above and beyond spatial and cultural autocorrelation. The amount of variation explained depended on the metrics used, with current levels and average levels of ecological conditions explaining the greatest amounts of variance in human culture on average (16% and 20%, respectively).
Form–function relationships underlie rapid dietary changes in a lizard
Authors: Taverne M. , Watson P. J. , Dutel H. , Boistel R. , Lisicic D. , Tadic Z. , Fabre A-C. , Fagan M. J. , Herrel A.
Published: June 2023

Macroevolutionary changes such as variation in habitat use or diet are often associated with convergent, adaptive changes in morphology. However, it is still unclear how small-scale morphological variation at the population level can drive shifts in ecology such as observed at a macroevolutionary scale. Here, we address this question by investigating how variation in cranial form and feeding mechanics relate to rapid changes in diet in an insular lizard (Podarcis siculus) after experimental introduction into a new environment. We first quantified differences in the skull shape and jaw muscle architecture between the source and introduced population using three-dimensional geometric morphometrics and dissections. Next, we tested the impact of the observed variation in morphology on the mechanical performance of the masticatory system using computer-based biomechanical simulation techniques. Our results show that small differences in shape, combined with variation in muscle architecture, can result in significant differences in performance allowing access to novel trophic resources. The confrontation of these data with the already described macroevolutionary relationships between cranial form and function in these insular lizards provides insights into how selection can, over relatively short time scales, drive major changes in ecology through its impact on mechanical performance.
Comparative genomics reveals intraspecific divergence of Acidithiobacillus ferrooxidans: insights from evolutionary adaptation
Authors: Liu Rui , Ma Liyuan , Wang Hongmei , Liu Deng , Lu Xiaolu , Huang Xinping , Huang Shanshan , Liu Xueduan
Published: June 2023

Acidithiobacillus ferrooxidans

serves as a model chemolithoautotrophic organism in extremely acidic environments, which has attracted much attention due to its unique metabolism and strong adaptability. However, little was known about the divergences along the evolutionary process based on whole genomes. Herein, we isolated six strains of

A. ferrooxidans

from mining areas in China and Zambia, and used comparative genomics to investigate the intra-species divergences. The results indicated that

A. ferrooxidans

diverged into three groups from a common ancestor, and the pan-genome is ‘open’. The ancestral reconstruction of

A. ferrooxidans

indicated that genome sizes experienced a trend of increase in the very earliest days before a decreasing tendency during the evolutionary process, suggesting that both gene gain and gene loss played crucial roles in

A. ferrooxidans

genome flexibility. Meanwhile, 23 single-copy orthologous groups (OGs) were under positive selection. The differences of rusticyanin (Rus) sequences (the key protein in the iron oxidation pathway) and type IV secretion system (T4SS) composition in the

A. ferrooxidans

were both related to their group divergences, which contributed to their intraspecific diversity. This study improved our understanding of the divergent evolution and environmental adaptation of

A. ferrooxidans

at the genome level in extreme conditions, which provided theoretical support for the survival mechanism of living creatures at the extreme.